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CROSS-REFERENCE TO RELATED APPLICATIONS [0001] The present application is a continuation of pending International patent application PCT/EP2006/063776 filed on Jul. 3, 2006, which designates the United States and claims priority from German patent application 10 2005 032 883 filed on Jul. 14, 2005, the content of which is incorporated herein by reference. FIELD OF THE INVENTION [0002] The invention relates to an apparatus for treatment, in particular physiotherapeutic treatment, of a part of the human body, in particular an arm, comprising a holder for fixing the body part to be treated, in particular the lower arm in the region of the elbow, and comprising a traction element, which acts on the body part, in particular on the wrist of the arm, and by means of which a traction of a predeterminable tension, directed in the direction of extent of the body part, in particular the lower arm, is exerted on the body part, in particular the lower arm. BACKGROUND OF THE INVENTION [0003] Such an apparatus is already known from DE 102 14 996 A1. The apparatus has an elongated apparatus housing. A holder, a traction element and a control console are disposed on the apparatus housing. The elements listed lie one behind the other in the longitudinal extent of the apparatus housing. The holder can be manually displaced in the longitudinal extent of the apparatus housing, since it is disposed on a rail. When the desired position has been reached, the holder can be fixed on the rail by means of a lever screw. The traction element can be displaced from the holder in the direction of the control console by a gear mechanism driven by an electric motor. Consequently, a tensile force can be exerted on an arm restrained in the holder, which is also fixed to the traction element by means of a cuff, since the traction element is displaced from the holder in the direction of the control console. A lower frame is disposed underneath the apparatus housing. [0004] It is an object of the invention to improve the generic apparatus advantageously in terms of its use and to increase the success of the therapy. SUMMARY OF THE INVENTION [0005] The object is achieved by each individual claim alone and by any combination whatever of each claim with any other claim as desired. [0006] Claim 1 provides first and foremost that the tension is applied by one or more weights acting on the traction element via a tension transmitting means, it being possible for the tensile force acting on the body part, in particular on the wrist, to be varied or stopped at the beginning, during and/or at the end of the treatment by a counteracting force applied by a motor. [0007] The following details are preferred: the traction cable forms the tension transmitting means. The traction cable is guided in particular over a deflecting roller. At least one weight is guided in a standing leg of the apparatus. A traction rod provided with holes is secured to the tension transmitting means, in particular to the traction cable. This traction rod passes through a multiplicity of weight-exerting plates, which are disposed one above the other and are provided with an opening. The weight-exerting plates have coupling openings for a coupling bolt to be passed through. The coupling bolt may be inserted into a coupling opening as far as and into a hole in the traction rod. The coupling bolt arrests a weight-exerting plate and those lying above it on the traction rod. A cuff associated with the traction element is provided for securing the body part, in particular the wrist. The traction element comprises a carriage on which the tension transmitting means acts on one side and a counteracting force transmitting means, in particular in the form of a cable, acts on the opposite side. The counteracting force transmitting means exerts the counteracting force on the traction element. Furthermore, the counteracting force transmitting means may displace the traction element in a motorized manner into an initial position. An electric motor acts on the traction element in order to apply the counteracting force and/or displace the traction element back. The electric motor may be a linear drive, a threaded spindle or a cable winch. The motor drive that applies the counteracting force or brings about the return displacement has a switchable freewheeling mechanism, which acts on the traction element. The motor drive applying the counteracting force or bringing about the return displacement acts on the traction element via a coupling that can be released in a damped manner. [0008] Such an apparatus is used for example for treating carpal tunnel syndrome. Treatment with this apparatus can obviate the need for an operation. Since operations always entail risks, treatment of carpal tunnel syndrome with the apparatus represents a good alternative. [0009] Instead of a traction cable, the tension transmitting means may also be formed by a chain, a wire or a lever mechanism. For example, a traction rod could act on the carriage. Instead of the deflecting roller, a deflecting lever could then be provided. For example, the traction rod could act on an arm of an angle lever which is pivotably mounted about an axis. A further traction rod, which can be connected to weights, may be articulated on the other arm of this angle lever. It is also conceivable to transmit the tensile force hydropneumatically. For this purpose, a pneumatic cylinder may act on the carriage. The cylinder is connected by a pipeline or a flexible tube to a further pneumatic cylinder, on which the weights act. The force transmission may take place by means of negative pressure, but with preference by means of positive pressure. The weights then exert a compressive force on the cylinder and the cylinder or piston likewise exerts a compressive force on the carriage. Technically, however, these forces bring about a traction on the arm of the patient. [0010] The counteracting force may also be applied to the carriage by a rope, a wire, a chain or a lever mechanism. It may also be applied to the carriage hydropneumatically. The motor drive is in this case a pump. It is also conceivable to transmit the forces via spindles or worm gear mechanisms. BRIEF DESCRIPTION OF THE DRAWINGS [0011] The invention just described is explained in more detail on the basis of an exemplary embodiment. In the drawing: [0012] FIG. 1 shows the front view of the apparatus in the starting position, which is represented partly in section, [0013] FIG. 2 shows a plan view of the apparatus corresponding to viewing direction II from FIG. 1 , [0014] FIG. 3 shows a side view of the apparatus corresponding to viewing direction III from FIG. 1 , [0015] FIG. 4 shows a view corresponding to FIG. 1 , but here the traction element has been displaced into an initial position, [0016] FIG. 5 shows a view corresponding to FIG. 4 , but here an arm has been restrained, [0017] FIG. 6 shows a view corresponding to FIG. 5 , the device now exerting a tensile force on the arm (cable 27 is substantially stress-free), [0018] FIG. 7 shows a plan view of the apparatus with a restrained arm, corresponding to viewing direction VII from FIG. 6 , and [0019] FIG. 8 shows how the apparatus can be transported. DETAILED DESCRIPTION OF THE INVENTION [0020] The apparatus 1 is represented in FIGS. 1 to 3 in the starting position. The apparatus 1 according to the invention is substantially constructed in the way described in the previously mentioned document of DE 102 14 996 A 1. It substantially comprises an apparatus housing 2 with the holder 3 , the traction element 4 and the control console 5 disposed on it. A lower frame 6 is disposed underneath the apparatus housing 2 . [0021] The elongated apparatus housing 2 has on its upper side a rail 7 . One end of the rail 7 lies in the end region of the apparatus housing 2 . The rail 7 extends from there to approximately the middle of the longitudinal extent of the apparatus housing 2 . In FIG. 1 , the end of the rail 7 lies in the left-hand end region of the apparatus 1 . The holder 3 is displaceably mounted on the rail 7 . It can be displaced in the longitudinal extent of the apparatus housing 2 . By means of a lever screw 8 , the holder 3 can be fixed in any desired position on the rail 7 . In the direction of extent of the rail 7 , the latter is followed by two laterally located control buttons 9 . They are disposed approximately in the middle of the apparatus 1 . By pressing these buttons 9 , the patient can interrupt the treatment. [0022] Behind the buttons 9 in the direction of extent of the rail 7 is the traction element 4 . This is constructed as in DE 102 14 996 A1. It substantially comprises a pillar 10 , a shoe 11 disposed over the latter and a cross bar 12 disposed on that. Disposed to the side of the shoe 11 is a lever screw 13 . This protrudes through an oblong hole 14 into a threaded bore of the pillar 10 . By means of the lever screw 13 , the adjusted height of the shoe 11 can be fixed. Disposed on the pillar 10 in the direction of the holder 3 is a pivot bearing 15 . The traction element 4 can be pivoted about this pivot bearing 15 when an overload preventer 16 has tripped. The overload preventer 16 may be formed by a bolt which simply shears off under excessive loading. [0023] As can be gathered from FIG. 3 , the cross bar 12 is fixed on the shoe 11 such that it is pivotably movable about a pivot point 17 . Disposed underneath the pivot point 17 is an arcuate slot 18 . The arcuate slot 18 runs concentrically with respect to the pivot point 17 . A tightening screw 19 protrudes through the slot 18 into the shoe 11 . With the tightening screw 19 , the cross bar 12 can be fixed in any desired angular position in relation to the shoe 11 . The maximum angular positions of the cross bar 12 are limited by the respective end of the arcuate slot 18 . [0024] The traction element 4 is guided in a longitudinal slot 20 . The guidance of the traction element 4 in the apparatus housing 2 may be constructed for example in the way described in DE 102 14 996 A1. The cross bar 12 runs transversely in relation to the longitudinal extent of the apparatus housing 2 . [0025] The control console 5 is disposed in the other end region of the apparatus housing 2 . In FIG. 3 it can be seen that an emergency-shutdown button 21 , an initial button 22 , a starting button 23 , a buzzer 24 and a display 25 are disposed on the control console 5 . [0026] In the event of a malfunction, the apparatus 1 can be immediately switched off by means of the emergency-shutdown button 21 . In order to reach the initial position ( FIG. 4 , FIG. 5 ) from the starting position ( FIGS. 1 to 3 ), the initial button 22 must be pressed. In order that the treatment can be started, the starting button 23 must be subsequently actuated. The display 25 indicates the individual repetitions in two digits. When a series or the entire treatment has been completed, an acoustic signal emitted by the buzzer 24 is sounded. [0027] Disposed underneath the traction element 4 in the apparatus housing 2 is a carriage 26 . The traction element 4 is secured to the carriage 26 . It protrudes through the longitudinal slot 20 . By means of the carriage 26 , the traction element 4 is guided in the longitudinal slot 20 . A counteracting force transmitting means 27 acts on the side of the carriage 26 that faces the holder 3 . The counteracting force transmitting means 27 is formed by a cable. A tension transmitting means 28 acts on the other side of the carriage 26 , which faces the control console 5 . This tension transmitting means is likewise formed by a cable. Both cables 27 , 28 run in the housing 2 and cannot be seen from the outside. [0028] A motor drive in the form of an electric motor 29 acts on the cable 27 . The electric motor 29 drives a cable winch 51 . Both are disposed in the end region of the device housing 2 underneath the rail 7 . The electric motor 29 and the cable winch 51 are connected to each other via a switchable freewheeling mechanism. Furthermore, the coupling between the electric motor 29 and the cable winch 51 can be released in a damped manner. [0029] The cable 28 is guided by means of a deflecting roller 30 in the direction of a standing leg 31 of the lower frame 6 . The deflecting roller 30 and the standing leg 31 are disposed underneath the control console 5 . The standing leg 31 comprises a hollow body in which weight-exerting plates 32 are disposed one above the other. In the exemplary embodiment, fifteen weight-exerting plates 32 are disposed one above the other. From top to bottom, one weight-exerting plate 32 of 6 kg, six of 1 kg and eight of 1.5 kg are stacked. It is possible to choose 6 kg, from 7 kg to 12 kg in intervals of 1 kg and from 13.5 kg to 24 kg in intervals of 1.5 kg. It is possible to set a weight from 6 kg to 24 kg. The weight-exerting plates 32 have a central opening 33 . The openings 33 run in the direction of extent of the standing leg 31 , that is to say perpendicular to the direction of extent of the apparatus housing 2 . Furthermore, the weight-exerting plates 32 have coupling openings 34 . The coupling openings run perpendicular to the openings 33 , that is to say in the direction of the longitudinal extent of the apparatus housing 2 . [0030] In the starting position of the apparatus 1 , a traction rod 35 provided with holes protrudes through each opening 33 of the weight-exerting plates 32 . The traction rod 35 has holes 52 at the location of the coupling openings 34 . This rod is connected to the tension transmitting means 28 . In order to connect the weight-exerting plates 32 to the traction rod 35 , a coupling bolt 36 must be inserted into a coupling opening 34 of a weight-exerting plate 32 and through a hole 52 of the traction rod 35 . The coupling bolt 36 consequently protrudes through the weight-exerting plate 32 and the traction rod 35 . As a result, the weight-exerting plate 32 through which the coupling bolt 36 passes is connected to the traction rod 35 . Furthermore, the weight-exerting plates 32 that lie above the coupling bolt 36 are carried along by the traction rod 35 . In order that the coupling bolt 36 can be inserted into the weight-exerting plates 32 , the standing leg 31 has a longitudinal slot 37 . [0031] Disposed underneath the standing leg 31 is a cross beam 38 ( FIG. 3 ). As can be seen in FIG. 1 , adjustable feet 39 are provided at the sides of the cross beam 38 . These feet can be set by means of the thread in such a way that the apparatus 1 stands securely on the floor 40 . In order for the feet 39 to then be fixed, a lock nut 41 is provided. Respectively disposed laterally of the feet 39 in the direction of longitudinal extent of the apparatus 1 is a roller 42 . The rollers 42 face toward the end of the apparatus 1 that also accommodates the control console 5 . Disposed on the standing leg 31 underneath the apparatus housing 2 is a button 43 . The button 43 makes the apparatus 1 move from the initial position ( FIGS. 4 , 5 ) into the starting position ( FIGS. 1 to 3 ). [0032] Parallel to the standing leg 31 , a further standing leg 44 is disposed underneath the holder 3 . The two standing legs 31 , 44 are connected to each other by a connecting beam 45 . The connecting beam runs parallel to the longitudinal extent of the apparatus housing 2 . As can be seen in FIG. 3 , the standing leg 44 has a narrower cross-section than the standing leg 31 . On the side that is facing away from the standing leg 31 , the standing leg 44 has a handle 46 . In the basic position ( FIGS. 1 to 7 ), the handle 46 runs approximately parallel to the standing leg 44 . Underneath the apparatus housing 2 , the handle 46 is articulated in a pivotably movable manner on the standing leg 44 by means of a hinge 47 . [0033] In the following section, the operating mode of the exemplary embodiment is explained in more detail: [0034] Starting from FIGS. 1 to 3 , the apparatus 1 is in the starting position. In this position, the therapist can choose the weight for the treatment. For this purpose, the coupling bolt 36 has to be inserted into the desired weight-exerting plate 32 . This couples the weight of exerting plate 32 to the traction rod 35 . Likewise, the weight-exerting plates 32 that are located above the coupling bolt 36 are then also carried along by the traction rod 35 . A scale for the weight may be provided for example to be readable from the outside on the standing leg 31 . [0035] In order to displace the apparatus 1 into the initial position, the initial button 22 must be actuated. By actuating the initial button 22 , the electric motor 29 is activated. The electric motor 29 acts by means of the cable winch 51 on the cable 27 . The rolling up of the cable 27 on the cable winch 51 , which is driven by the electric motor 29 , has the effect that the carriage 26 with the traction element 4 is displaced as far as possible in the direction of the holder 3 . When the traction element 4 has assumed the initial position, the electric motor 29 stops. The displacement path of the carriage 26 with the traction element 4 disposed on it is limited by the longitudinal slot 22 . In this position, an arm 48 , which is bent at right angles, can be fixed in the holder 3 by means of straps 49 . One strap 49 is placed around the upper arm and the other strap 49 is placed around the lower arm. Furthermore, a cuff 50 is placed around the wrist of the arm 48 and then secured to the cross bar 12 . In this case, the inner surface of the hand is facing upward. This position is illustrated in FIG. 5 . There it can also be seen that the holder 3 is at a distance from the traction element 4 such that the cuff 50 is not yet exerting any tensile force on the arm 48 . The position of the holder 3 in relation to the traction element 4 can be varied on the rail 7 . The holder 3 is subsequently fixed on the rail 7 with the lever screw 8 . The height of the cross bar 12 in relation to the arm 48 can likewise be adjusted. This just requires the lateral lever screw 13 on the shoe 11 to be loosened and then the shoe 11 can be varied in its height. The height variation is limited by the length of the oblong slot 14 . Once the desired height has been reached, the shoe 11 can be fixed in its height by means of the lever screw 13 . [0036] When the apparatus 1 has been set optimally for the patient, the counteracting force transmitting means 27 is slowly released by actuating the starting button 23 . This is possible, since the coupling between the electric motor 29 and the cable winch 51 can be released in a damped manner. As a result, the tensile force on the arm 48 builds up only slowly. In FIGS. 6 and 7 , the tensile force that is applied by the weight-exerting plates 32 acts on the arm 48 . The time between starting the operation and reaching the end position ( FIGS. 6 , 7 ) is approximately 7 seconds, with the tensile force being maintained for approximately 2 seconds. Once the time has expired, the electric motor 29 automatically switches on again and, by winding up the cable 27 onto the cable winch, displaces the carriage 26 with the traction element 4 back again into the initial position. After that, the electric motor 29 switches off and the coupling slowly releases the cable roller 51 , so that the tensile force can build up once again. This operation is repeated for example ten times. The displacement into the initial position through to renewed starting of the tractive movement takes approximately 5 seconds. [0037] The repetitions are indicated on the display 25 . After completion of the ten repetitions, an acoustic signal sounds from the buzzer 24 . The apparatus 1 is again in the initial position, which is illustrated in FIG. 5 . The position of the cross bar 12 can be changed. This is schematically represented in FIG. 3 . As a result, the wrist can be moved into a different position. For this purpose, the tightening screw 19 must be released, and then the cross bar 12 can be pivoted about the pivot point 17 . The maximum position of the cross bar 12 is limited by the arcuate slot 18 . When the desired position of the cross bar 12 has been reached, the cross bar 12 can be fixed by means of the tightening screw 19 . After renewed actuation of the starting button 23 , the repetitions, for example ten of them, are carried out once again. After completion of the ten repetitions, the position of the cross bar 12 can be varied again. A customary treatment on this apparatus 1 provides three sets of ten repetitions. [0038] The two buttons 9 allow the patient to interrupt the treatment. If the button 9 is pressed, the traction element 4 moves back into the initial position. After renewed pressing of the button 9 , the treatment is continued until the ten repetitions have been performed. If a treatment has been completed and a new patient requires a different weight, the button 43 on the standing leg 31 must be actuated from the position that is represented in FIG. 4 . Actuating the button 43 makes the electric motor 29 displace the apparatus 1 into the position corresponding to FIGS. 1 to 3 . Only in this position is it possible to change the weight without raising the weights. [0039] In FIG. 8 it is shown how the apparatus 1 can easily be moved. The handle 46 is pivoted about the pivot point of the hinge 47 such that the handle 46 is positioned approximately at right angles to the standing leg 44 . The handle 46 butts against the underside of the apparatus housing 2 . The apparatus 1 can then be lifted up by the handle 46 . This shifts the weight from the standing legs 31 , 44 onto the two rollers 42 . In this position, which is represented in FIG. 8 , the apparatus 1 can easily be displaced by means of the rollers 42 . Once the desired position has been reached, the apparatus 1 is slowly let down and the handle 46 is swung against the standing leg 44 . The apparatus 1 can then be aligned by means of the feet 39 , which are then fixed by means of a lock nut 41 . [0040] As in the previously mentioned DE 102 14 996 A1, the apparatus 1 is likewise fitted with an overload preventer 16 in the traction element 4 . If for some reason any kind of excessive load is exerted on the arm 48 during a treatment, the overload preventer 16 trips and allows pivoting of the traction element 4 in the direction of the holder 3 by means of the pivot bearing 15 . As a result, the load is removed from the arm 48 . [0041] In the case of the exemplary embodiment described above, the tensile force was transmitted to the carriage 26 from the traction rod 35 carrying the weights via a cable 28 . However, alternative ways in which the weight force of the weights 32 can be transmitted to the traction element 4 are also conceivable. For example, instead of the traction cable 28 , a wire or a chain may be provided. An alternative to the deflecting roller 30 is an angle lever. This angle lever may have two lever arms at right angles to each other. This angle lever can be pivoted about a pivot axis which is associated with the apex of the two lever arms. A traction rod may act on each of the two lever arms. One traction rod is connected to the traction element and the other is connected to the weights. One traction rod may act for example on the carriage 26 . The other traction rod may be the traction rod 35 carrying the weights. However, there may also be a coupling rod, which is articulated on the traction rod 35 and is connected to the corresponding arm of the angle lever. [0042] As an alternative to these solutions, the weight force of the weights 32 may also be transmitted to the traction element 4 pneumatically, and in particular hydropneumatically. For this purpose, a pulling piston or a pushing piston of a piston/cylinder unit may for example act on the carriage 26 . This piston/cylinder unit is connected via flexible tubes or pipelines to a second piston/cylinder unit, which is acted upon by the weights 32 . [0043] In the same way as the tensile force acting on the traction element 4 can act via different force transmitting means, the restoring force that is applied by the electric motor 29 can be transmitted to the traction element 4 via the various force transmitting means. Here, too, a wire or a chain may be used instead of a traction cable 7 . The motor 29 may drive a winding drum. However, here it may also be a linear drive. In the same way, here, too, a hydropneumatic drive may be provided for displacing the traction element 4 back in the direction of the holder 3 . For this purpose, a piston/cylinder unit may act on the traction element 4 , and in particular on the carriage 26 . Said unit may comprise a pulling piston or a pushing piston. If the tensile force is also transmitted via a piston/cylinder unit, a double-piston arrangement is suitable here. The restoring force is in this case applied by way of a pump or a second piston/cylinder unit. [0044] As an alternative to the types of drive described above, a geared spindle drive may also be used. [0045] All features disclosed are (in themselves) pertinent to the invention. The disclosure content of the associated/attached priority documents (copy of the prior application) is also hereby incorporated in full in the disclosure of the application, including for the purpose of incorporating features of these documents in claims of the present application.

The invention relates to an apparatus for treatment, in particular physiotherapeutic treatment, of a part of the human body, in particular an arm, comprising a holder for fixing the body part to be treated, comprising a traction element, which acts on the body part with a predeterminable tension. The tension is applied by one or more weights acting on the traction element via a tension transmitter, it being possible for the tensile force acting on the body part to be varied or stopped at the beginning, during and/or at the end of the treatment by a counteracting force applied by a motor.

FIELD OF THE INVENTION The present invention relates to polyolefin/clay nanocomposites, more particularly, to poly-α-olefin/clay nanocomposites, and to a process for the preparation of the same. BACKGROUND OF THE INVENTION The conventional process for preparing thermoplastic composite materials is either dry-blending polymers with filling materials or adding filling materials into a melt of polymers and then mixing them. The resulting materials are disadvantageous for non-uniform distribution of the filling materials in the polymer matrix, thus largely decreasing their strength compared to the polymers containing no filling materials. By filling polymers with superfine inorganic compounds, the resulting composite materials can have largely improved properties, and however, when the filling materials have a particle size less than 0.1 micron, it is difficult to have the filling materials dispersed in nanometeric scales by using the conventional blending process and only a micro-dispersed composite material can be prepared for very large self-aggregating force among the particles caused by very large surface areas. On the other hand, polyolefin materials with high or ultrahigh molecular weight have excellent mechanical properties and their application fields are being gradually broadened, however, when they are modified with superfine inorganic materials, the outstanding problem encountered is large power consumption and non-uniformity of the resulting composite materials. In order to effectively solve the problem in terms of uniform dispersion of filling materials within the polymer matrix, a novel process, i.e. in-situ polymerization-composition, is proposed, in which a component having catalytic activity is supported on filling materials having high dispersibility and the polymerization reaction is then carried out on the surface of the filling materials to obtain a composite material. For example, U.S. Pat. No. 5,352,732 disclosed a homogeneous composite comprising (a) 10 to 99.5% by weight of an ultrahigh molecular weight linear polyethylene having a molecular weight of at least about 400,000 and (b) 0.5 to 90% by weight of at least one inorganic filler compound having a neutral-to-acidic surface, said filler compound being an inorganic compound selected from the group consisting of alumina hydrates, silicas, calcium carbonate, hydroxyapatite, calcium hydrogen phosphate and clays. The composite of '732 is prepared by supporting a transition metal as active ingredient onto the surface of the inorganic filler and then carrying out polymerization reaction on said surface. While the mechanical properties of said composite are improved to some extent, the manufacturing process is relatively complicated and the thermal treatment at high pressure is necessary after polymerization. Chinese Patent Application Publication No. CN 1138593A discloses a polyamide/clay nanocomposite, prepared by intercalation polymerization method, in which a clay having cationic exchange capacity is mixed with a lactam monomer in the presence of a dispersing medium, the cationic exchange reaction and monomer intercalation reaction are carried out in the stabilized colloidal dispersion system formed with stirring at high speed, and then the lactam is polymerized by adding a catalyst, to obtain the composite. The clay used in the synthesis of said composite is montmorillonite. An object of the present invention is to provide a polyolefin/clay nanocomposite, which has excellent mechanical properties and thermal resistance. Another object of the present invention is to provide a process for the preparation of the polyolefin/clay nanocomposite according to the present invention, which is simpler compared to the processes employed in the prior art. These and other objects, features and advantages of the present invention will be readily apparent to those skilled in the art from the following description taken in connection with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a transmission electron microscopic(TEM) image of a sample of the composite prepared in Example 1 of the present invention(at a magnification of 20,000); FIG. 2 is a TEM image of a sample of the composite prepared in Example 2 of the present invention(at a magnification of 150,000); FIG. 3 is a TEM image of a sample of the composite prepared in Example 3 of the present invention(at a magnification of 20,000); FIG. 4 is a TEM image of another sample of the composite prepared in Example 3 of the present invention(at a magnification of 20,000); FIG. 5 is a cross-sectional scanning electron microscopic(SEM) image of a sample of the composite prepared in Example 5 of the present invention(at a magnification of 8,000); and FIG. 6 is a TEM image of a sample of the composite prepared in Example 6 of the present invention(at a magnification of 20,000). SUMMARY OF THE INVENTION The composite according to the present invention comprises from 40 to 99.9% by weight of polyolefins and from 0.1 to 60% by weight of a sepiolite-palygorskite type clay. The content of said clay in the composite according to the present invention is preferably from 0.1 to 40% by weight, most preferably from 1.0 to 10% by weight. The composite according to the present invention is prepared by a process comprising: (a) calcining the sepiolite-palygorskite type clay in an atmosphere of air or an inert gas at a temperature of 100 to 850° C., preferably 300 to 850° C., for 0.5 to 10.0 hours; (b) suspending thus-calcined clay in an inert hydrocarbon solvent and then reacting with a transition metal compound at a temperature of 0 to 200° C. for 0.5 to 6.0 hours to obtain a solid product, in which the transition metal compound is used in an amount of 0.05 to 100 millimoles, preferably 0.05 to 50 millimoles, per gram of clay; and (c) polymerizing an olefin at a temperature of 20 to 150° C., preferably 60 to 90° C., with the solid product from step (b) as the catalyst and an organic aluminum compound as the co-catalyst. DETAILED DESCRIPTION OF THE INVENTION Composite of the Invention The polyolefin employed in the composite according to the present invention is preferably polymers of α-C 2 ˜C 6 olefins, more preferably polyethylenes. Said polyethylenes may be high or ultrahigh molecular weight polyethylenes, with a weight-average molecular weight of 20×10 4 to 600×10 4 , preferably 40×10 4 to 600×10 4 . Also suitable are copolymers of ethylene with at least one comonomer selected from the group consisting of propylene, 1-butene, 1-pentene, 1-hexene and 1 octene. The sepiolite-palygorskite type clay used in the composite according to the present invention is any one selected from the group consisting of sepiolite, palygorskite and attapulgite, with sepiolite or attapulgite being preferred. The sepiolite-palygorskite type clays are a class of hydrated magnesium aluminosilicates, each layer of which is silica tetrahedral arrays having two or three double chains per edge, with five or eight alumina octahedral sheets sandwiched therebetween, and the unit layers are linked by oxygen atoms to form a crystal structure containing channels. Therefore, the sepiolite-palygorskite type clays have a crystal structure between a chain structure and a layer structure, of which the monocrystals are in the forms of fiber, rod or needle, with different degrees of development, and have a diameter of about 10 to 100 nanometers, some of which being as long as several microns to several tens of microns. This class of clays includes sepiolite, palygorskite and attapulgite. The unit layers of sepiolite have three double-chained silica tetrahedral sheets at each of the upper edges and the bottom edges, with eight alumina octahedral sheets sandwiched therebetween. The unit layers are linked by oxygen atoms to form a crystal structure containing channels. The chemical formula of sepiolite is Si 12 Mg 8 O 30 (OH) 4 (OH 2 ) 4 .8H 2 O. Palygorskite and attapulgite have the same chemical compositions and crystal structures, but there are some differences in their natures. For example, palygorskite has good crystallization property, longer fibers and soft appearance; and attapulgite has poor crystallization property, very short fibers, tight appearance and high content of iron. Therefore, attapulgite is a subspecies of palygorskite. The unit layers of palygorskite have two double-chained silica tetrahedral sheets at each of the upper edges and the bottom edges, with five alumina octahedral sheets sandwiched therebetween. The unit layers are linked by oxygen atoms to form a crystal structure containing channels. The chemical formula of palygorskite is Si 8 Mg 5 O 20 (OH) 2 (OH 2 ) 4 .4H 2 O. Preparation of the Composite of the Invention The above process for the preparation of the composite according to the present invention may additionally comprise a step (a 1 ), in which said clay calcined in step (a) is treated with an alkyl metal compound, prior to being used for steps (b) and (c). Particularly, in step (a 1 ), the calcined clay from step (a) is suspended in an inert hydrocarbon solvent, the alkyl metal compound is added in an amount of 0.05 to 100 millimoles per gram of clay to the resulting suspension and then the resulting mixture is reacted at a temperature of 0 to 200° C. for 0.5 to 6.0 hours. Prior to use, various clays may be subjected to pretreatment, if necessary, depending on the purity of the natural crude minerals. The purpose of pretreatment is to remove non-clay impurities, such as quartz sand, calcium carbonate and the like. Said pretreatment can be carried out in a manner as described in Chinese Patent Application Publication No. CN1044772A. The Clay used in the present invention may be in powdered form, particulate form or spherical form. The clay in spherical form may be formed by spray drying, with a diameter of 20 to 80 microns. The inert gas used in step (a) may be nitrogen, helium or argon, with nitrogen being preferred. The transition metal compounds used in step (b) may be one of halides, oxyhalides, C 1 ˜C 12 alkoxyhalides or hydrohalides of a transition metal selected from the group consisting of titanium(Ti), zirconium(Zr), hafnium(Hf), vanadium(V), nickel(Ni), scandium(Sc), niobium(Nb) and tantalum(Ta), or the mixtures of any two of them. Preferred are halides or oxyhalides of Ti or V, such as TiCl 4 , TiCl 3 , Ti(OCH 3 )Cl 3 , Ti(OC 6 H 5 )Cl 3 , or Ti(OCOC 6 H 5 )Cl 3 , with TiCl 4 being more preferred. The inert hydrocarbon solvents used in the process according to the present invention may be C 5 -C 10 alkanes, gasoline, kerosine or petroleum ether, with n-hexane, n-heptane, n-octane or n-nonane being most preferred. In step (c), the molar ratio of aluminum contained in the organic aluminum compounds to the transition metal contained in the solid catalyst may be 10 to 300. The organic aluminum compounds can be selected from the group consisting of alkyl aluminums, alkyl aluminum halides and aluminum alkoxides, such as triethyl aluminum(Al(C 2 H 5 ) 3 , diethyl aluminum chloride(Al(C 2 H 5 ) 2 Cl), triisobutyl aluminum(Al(i-C 4 H 8 ) 3 ), Al 2 (C 2 H 5 ) 3 Cl 3 , diisobutyl aluminum(Al(i-C 4 H 9 ) 2 H), trihexyl aluminum(Al(C 6 H 13 ) 3 ), diethyl aluminum(Al(C 2 H 5 ) 2 H) and diethyl aluminum ethoxide(Al(C 2 H 5 ) 2 (OC 2 H 5 )). Preferred are alkyl aluminums, with triethyl aluminum and triisobutyl aluminum being most preferred. The polymerization reaction in step (c) can be carried out in gas phase or liquid phase, at normal pressure or at a pressure of 0.01 to 1.0 MPa. When employing liquid phase polymerization, it can be carried out in the absence or presence of an inert hydrocarbon diluent. The diluent may be hexanes, heptanes or octanes. The alkyl metal compounds used in step (a 1 ) can be selected from the group consisting of alkyl aluminum compounds, alkyl alkaline earth metal compounds and alkyl zinc compounds. Preferred are alkyl aluminum compounds or alkyl alkaline earth metal compounds, such as alkyl magnesium compounds, triethyl aluminum or triisobutyl aluminum, with dibutyl magnesium, n-butyl ethyl magnesium and di-hexyl magnesium being more preferred. According to the present invention, a sepiolite-palygorskite type clay, of which the monocrystals have a diameter of the order of nanometers, is used as the filling material and the composite is prepared by polymerizing olefins on the clay with active components supported thereon. The composite thus obtained has good interfacial adhesion between the clay and the polyolefin matrix, with the former uniformly dispersed in the latter in nanometric scales, thereby the composite has largely improved mechanical properites and thermal stability. EXAMPLES The following examples illustrate the present invention but are not limitative. In the examples, the molecular weight of the composite is measured by Gel Permeation Chromatography(GPC) method; the tensile strength is measured according to ISO507-93, Vicat temperature is measured according to ISO306-94 and the Izod impact strength(notched) is measured according to ISO179-97. In the examples, the Decalin-insolubles (decahydronaphthalene-insolubles) are used as a measure of the interaction degree in the interface between the two phases of the composite, which are measured as follows: the composite and Decalin are added to a Soxhlet, extractor in a ratio of 1000 ml Decalin per gram of the composite and then are extracted at the reflux temperature for 20 hours. After that time, the insolubles are dried and weighed. Example 1 In this example a sepiolite/polyethylene nanocomposite is prepared. 2.0 g of sepiolite(natural minerals, available from Quanjiao, Anhui Province, China) is ground to powders and is then calcined at a temperature of 200° C. for 6 hours. Thus calcined clay is mixed with 100 ml of heptane to obtain a suspension, to which is added 1 ml of TiCl 4 (Beijing Zhonglian Chemical Reagents Company, industrial grade). The resulting mixture is heated to reflux and then is reacted at reflux for 2 hours. The reaction mixture is filtered to obtain a solid, which is in turn washed three times at a temperature of 30 to 60° C. with 30 ml of hexane and then is dried at a temperature of 60° C. under nitrogen stream for 0.5 to 1 hour to obtain a solid catalyst with a titanium content of 1.9% by weight. The inside of a 500 ml of three-necked flask, equipped with a stirrer and a thermostatic system, is displaced three times with nitrogen and then one time with ethylene. Subsequently, to the flask are added 200 ml of hexane, 4 ml of triisobutyl aluminum solution(1.5M in hexane) and 2.5 g of the solid catalyst in that order, the stirrer is started and then ethylene gas is fed. The mixture is reacted at a temperature of 40° C. and normal pressure for 2 hours, then the stirrer is stopped and 2 ml of ethanol is added to quench the reaction mixture. After separating hexane and the polymer, the resulting polymer is dried in an oven to obtain 40 g of composite as white powders. The composite has a clay content of 4.7% by weight as measured by thermogravimetry. The molecular weight, mechanical properties and decalin-insolubles of the composite are summarized in Table 1. An ultra-thinnly sliced sample of the composite is analyzed by transmission electron microscopy(TEM) at a magnification of 20,000. The result is shown in FIG. 1, from which it can be seen that the clay fibers are uniformly dispersed in the polyethylene matrix in nanometric scales. Example 2 2.5 g of sepiolite is ground to powders and then is calcined as described in Example 1. To thus-calcined sepiolite is added 6 ml of triisobutyl aluminum solution(1.5M in hexane) and the resulting mixture is then stirred at a temperature of 200° C. for 2 hours. Subsequently, 1 ml of TiCl 4 is supported as described in Example 1 to obtain a solid catalyst. By using the catalyst, a polymerization reaction is carried out to obtain 200 g of composite as white powders, with a clay content of 1.6% by weight The mechanical properties and other test data of the composite are summarized in Table 1. An ultra-thinnly sliced sample of the composite is analyzed by transmission electron microscopy at a magnification of 150,000. The result is shown in FIG. 2, from which it can be seen that the clay fibers have a thickness of 30-40 nanometers. Example 3 Attapulgite(natural minerals, available from Jiashan, Anhui Province, China) is ground to powders and then is shaped by spraying to obtain microspheres with a diameter of 20 to 80 microns. A catalyst is prepared by using 3.5 g of attapulgite microspheres as described in Example 1 and then is used to carry out a polymerization reaction, thus providing 45 g of composite microspheres with a clay content of 8.7% by weight. The mechanical properties and other test data of the composite are summarized in Table 1. An ultra-thinnly sliced sample of the composite is analyzed by transmission electron microscopy at a magnification of 20,000. The result is shown in FIG. 3, from which it can be seen that the clay fibers have a thickness less than 100 nanometers. FIG. 4 is a transmission electron microscopic(TEM) image of another sample of the composite, from which it can be seen that the clay fibers are uniformly dispersed in the polyethylene matrix in nanometric scales. Example 4 A solid catalyst is prepared as described in Example 3 and then a polymerization reaction is carried out as follows. The inside of a glass autoclave having a capacity of 1 liter is displaced three times with nitrogen and then one time with ethylene. To thus-displaced autoclave are fed 500 ml of hexane, 6 ml of triisobutyl aluminum solution (1.6M in hexane) and 2.5 g of the solid catalyst, followed by ethylene until the pressure within the autoclave reaches 0.7 MPa. Stirring is started and then the temperature is raised to 45° C. There resulting mixture is reacted at that temperature for 2 hours, with the pressure within the autoclave being maintained constant by continuously feeding ethylene. Then stirring is stopped and the reaction mixture is quenched by adding 2 ml of ethanol. After cooling at room temperature, the resulting suspension is filtered and the polymer is collected to obtain 94 g of composite with a particle size of 100 to 300 microns and a clay content of 3.3% by weight. The mechanical properties and other test data of the composite are summarized in Table 1. Example 5 A solid catalyst is prepared and then a polymerizaton reaction is carried out as described in Example 4 except that the polymerization time is changed to 4 hours. 150 g of composite is obtained, with a clay content of 2.3% by weight. The mechanical propreties and other test data of the composite are summarized in Table 1. The cross-section of the composite is analyzed by scanning electron microscopy at a magnification of 8,000. The result is shown in FIG. 5, from which it can be seen that attapulgite fibers are uniformly dispersed in polyethylene matrix and there is good interfacial adhesion therebetween. Example 6 3.5 g of attapulgite micorspheres produced in Example 3, having a diameter of 20 to 80 microns, is calcined at a temperature of 500° C. for 6 hours, and then is added to 100 ml of hexane to form a suspension under stirring. To the suspension is added 0.1 ml of TiCl 4 and the resulting mixture is then reacted at the reflux temperature for 1 hour. Subsequently, the reaction mixture is washed and dried in a manner similar to Example 1 to obtain a solid catalyst with a titanium content of 1.1% by weight. By using the solid catalyst, a polymerization reaction is carried out as described in Example 4 to obtain 108 g of composite micospheres with a clay content of 2.4% by weight. The mechanical properties and other test data of the composite are summarized in Table 1. An ultra-thinnly sliced sample of the composite is analyzed by transmission electron microscopy at a magnification of 20,000. The result is shown in FIG. 6, from which it can be seen that the clay fibers are uniformly dispersed in the polyethylene matrix in nanometric scales. Comparative Example 2.5 g of finely divided montmorillonite(preparation concentrate, available from Heishan, Liaoning Province, China) is dried in an atmosphere of nitrogen at a temperature of 200° C. for 6 hours and then a solid catalyst is prepared in a manner similar to that of Example 1 except that the amount of TiCl 4 is changed to 2 ml. The resulting solid catalyst has a titanium content of 2.1% by weight. By using the solid catalyst prepared as above, a polymerization reaction is carried out as described in Example 1 except that the polymerization time is changed to 8 hours. A composite is obtained as white powders, of which the mechanical properties and other test data are summarized in Table 1. TABLE 1 Elong- ation Vicat Decalin- Properties At Temper- In- of the M. W. 1 T. S. 2 break ature I. S. 3 solubles 4 Materials (×10 4 ) (MPa) (%) (° C.) (kJ/m 2 ) (wt %) Example 1 300 29.8 308 133.5 89.6 66.8 Example 2 400 38.2 332 133.0 85.3 56.8 Example 3 420 28.0 300 133.1 86.5 73.6 Example 4 400 33.4 253 134.9 54.7 60.3 Example 5 500 35.4 158 132.9 72.3 54.5 Example 6 480 40.8 266 132.8 73.1 53.9 Comp. 260 19.0 326 130.0 68.8 23.6 Ex. 5 Note: 1 Molecular Weight; 2 Tensile Strength; 3 Impact Strength; 4 Based on the total weight of the composite; 5 Comparative Example.

Disclosed are polyolefin/clay nanocomposites, comprising 40 to 99.9% by weight of polyolefins and 0.1 to 60% by weight of sepiolite-palygorskite type clays selected from the group essentially consisting of sepiolite and attapulgite. The nanocomposites in accordance with the present invention have excellent mechanical properties and thermal resistance. Also disclosed is a process for preparing the polyolefin/clay nanocomposites according to the present invention.

FIELD OF THE INVENTION [0001] The present invention relates to the monitoring of the exhausting and/or release of active principles which are impregnated in textiles. BACKGROUND OF THE INVENTION [0002] Multiple applications of impregnated textiles which make possible the release or the administration of active principles have been developed since the 1990s. [0003] Mention may in particular be made, by way of illustration, of scarves impregnated with fragrance, impregnated “wipes” for hygiene and/or cleansing, or furnishing textiles (such as curtains and/or bed linen) which release insecticides and/or acaricides. [0004] Applications combining clothing and cosmetics have now been added to this list of applications which is enumerated above. Thus, clothes have been created which are composed of fibers capable of releasing active principles, such as slimming agents or moisturizing agents, essential oils, vitamins or indeed even deodorant products. [0005] Furthermore, such applications are also known in the pharmaceutical field, with dressings comprising healing or antimicrobial agents. [0006] The applications of these textiles impregnated with active principles are therefore highly varied. However, they all have the distinctive feature of confronting the user of these textiles with the same problem, which is of not being able to easily monitor if the textile is still sufficiently impregnated with active principles or if, on the contrary, reimpregnation of the textile with said active principles proves to be necessary due to their highly advanced release. [0007] This is because the rate of release of said active principles can vary according to the conditions of use and the number of washing operations carried out on the textile impregnated with active principles. Mention may be made, by way of example, of the case of furnishing fabrics, the active principles with which they are impregnated being released in multiple ways: [0008] as a result of the random exposure of these fabrics to the air or to the sun (conditions of use), [0009] as a result of the treatments, such as washing, to which these fabrics are subjected. [0010] Thus, for this reason, it is difficult to indicate, to the user, a precise “lifetime” for his impregnated textile since it is greatly influenced by the abovementioned parameters. [0011] In the field of impregnated textiles, a method which makes it possible to characterize the amount of active principles, as a function of the number of washing operations and of the washing conditions, is certainly known. It consists in chemically analyzing, after an extraction, the amount of active principles remaining after each washing operation on the impregnated textile. A remaining percentage of the active principles is thus calculated with respect to the initial amount impregnated in the textile. [0012] Thus, with this method, the user of the impregnated textile can be informed of a calibration indicating the remaining amount of active principles as a function of the number of washing operations which have been carried out is and can thus judge the need to carry out a reimpregnation of the textile as a result of the release, already highly advanced, of the active principles. [0013] However, this method has the following disadvantages: [0014] it takes into account only the release of the active principles by the washing operations and does not take into account the real conditions of use of the impregnated textile, which can be highly diverse, depending on the user, during which the active principles can also be released, [0015] conditions for washing the impregnated textile which are employed by the user, which are not necessarily identical to those which were employed in carrying out the calibration and, finally, [0016] it requires the user of the impregnated textile to have to keep count of the number of washing operations carried out. BRIEF DESCRIPTION OF THE INVENTION [0017] The present invention makes it possible to overcome the disadvantages listed above. This is because it provides a method for monitoring the release of active principles impregnated in a textile which is within the scope of the user. [0018] The present invention relates to a method for monitoring and/or following the release of at least one active principle impregnated in a first textile, characterized in that: a) there is available said first textile impregnated with said at least one active principle, b) there is available a monitoring label attached to said first textile and made of a second textile at least partially impregnated with a colorant, the amount of which is adjusted so that the decolorization of said label is proportional to the release of said at least one active principle, c) the amount of the at least one active principle released is evaluated by observation of the decolorization of said label. [0022] In this way, the user can follow the exhaustion of the textile in active principle by simple visual monitoring of the decolorization of the monitoring label and can therefore decide: on the need to recharge by spraying said textile, to affix a new label, which can be supplied with the container of the recharge emulsion or else which is produced directly by the user by spraying the colorant over the textile fibers constituting a new monitoring label. [0025] The method according to the invention can thus comprise an additional stage which consists, after having observed a partial or complete decolorization of said monitoring label, in spraying said at least one active principle over said first textile. It is also then possible to affix a new monitoring label to said first textile. [0026] This monitoring method exhibits the advantage of avoiding untimely rechargings which can prove to be dangerous and can result in the at least one active principle being charged in excessive amounts. This method also takes into account the conditions of use, such as the exposure to an environment, and also the washing conditions. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0027] The first textile and the monitoring label used in the method according to the invention are identical or different textiles which can be chosen from nonwoven, woven or knitted textiles. These textiles are composed of fibers which can be natural or synthetic, indeed can even be a mixture of these. [0028] The natural fibers are chosen from cotton, wool, silk and/or jute. [0029] The synthetic fibers are chosen from polyamides, polyesters, polyacrylonitriles, polyolefins, such as polypropylene or polyethylene, or Teflon. [0030] The fibers can be spun, carded or twisted. [0031] The monitoring label is attached to the first textile. It can, for example, be stitched to a portion of said first textile. [0032] As stated above, the amount of colorant is adjusted so that the decolorization of said label is proportional to the release of said at least one active principle. [0033] To achieve this, precise adjusting of the amount of colorant impregnated in the monitoring label is essential. This adjusting will also depend on the nature of the textile fibers of the monitoring label, which can influence the rate of release of the colorant. [0000] The amount of colorant will thus be appropriate, taking into account the washing operations and the conditions of use of the textile. Thus, it will be possible, in order to carry out this adjusting, for example, to carry out tests in which the release of the at least one active principle is followed in parallel with that of the colorant with which the monitoring label is impregnated. These tests in which the release is followed will have the aim of simulating as best as possible the conditions of use of the textile impregnated with at least one active principle. For example, these tests can simulate the conditions under which an item of clothing is worn or else can simulate the environmental conditions to which furnishing fabrics or curtains may be subjected. [0034] Specifically, the textile for which the monitoring and/or the following of the release of at least one active principle is intended can be an item of clothing, gloves, slippers, underwear, stockings or pantyhose, but also curtains, cushion or sofa covers, or wall textiles, or else medical articles, such as bandages, splints or dressings but also compresses, head bandages or masks. [0035] The at least one active principle can be chosen from pharmaceutical or cosmetic active principles, deodorizing agents, insecticides or acaricides. [0036] In the present invention, the at least one active principle can be chosen from slimming, refreshing or moisturizing active principles. [0037] The at least one active principle can be lipophilic or hydrophilic. [0038] Mention may be made, among lipophilic active principles, of: [0039] fat-soluble vitamins and their derivatives, such as the family of the retinoids, for example retinol, retinaldehyde or retinoic acid, of the carotenoids, or tocopherol and its derivatives, [0040] polyphenols, such as flavonoids, for example isoflavonoids, quercetin, stilbenes, for example resveratrol, or catechins, for example epicatechin 3-gallate or epigallocatechin 3-gallate, [0041] perfumery components, such as vanillin, indole or more generally essential oils, such as essential oils of citrus fruits or of lavender, [0042] fat-soluble pharmaceutical active principles, such as fluvastatin, ketoprofen, verapamil, atenolol, griseofulvin or ranitidine. [0043] The hydrophilic active principles can be chosen from aminoglucosides (gentamicin), antibiotics (β-lactam, sulbenicillin, cefotiam, cefmenoxime), peptide hormones (TRH, leuprolide, insulin), antiallergic, to antimycotic or cytostatic agents, anxiolytics, contraceptives, sedatives, mineral salts (calcium, chlorine, magnesium, phosphorus, potassium, sodium, sulfur), trace elements (aluminum, bromine, copper, cobalt, iron, fluorine, manganese, molybdenum, iodine, selenium, silicon, vanadium, zinc), amino acids (alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, valine), peptides, proteins, water-soluble vitamins, polyols, or indeed even flavorings. [0044] In a specific form of the invention, when the monitoring label is intended to follow the exhaustion of an active principle impregnated in an item of clothing, the colorant with which the monitoring label is impregnated can be chosen from the list of colorants which may be present in cosmetic products drawn up in Annex IV of Directive 76/768/EEC. Thus, should the monitoring label be in contact with the skin, there will be no risk of toxicity. [0045] The at least one active principle can be in the form of nanoparticles or of microparticles or else in solution. [0046] The colorant can be in the form of nanoparticles or of microparticles or else in solution. [0047] The at least one active principle and the colorant can be in identical or different forms. [0048] In one embodiment of the invention, the at least one active principle and/or the colorant can be in the form of microparticles which can be chosen from microcapsules or microemulsions. [0049] In one embodiment of the invention, the at least one active principle and/or the colorant can be in the form of nanoparticles, the size of which is less than 300 nm (0.3 μm), on average 150 nm. [0050] Mention may in particular be made, among the nanoparticles which can be used in the present invention, of titanium dioxide, zinc oxide, fullerenes, nanocrystals (also known as quantum dots; namely semiconducting crystals) and nanoemulsions, nanocapsules, nanospheres, nanovesicles or spherulites. [0051] As regards the nanoparticles in the nanoemulsion form, they can be obtained by any process known to a person skilled in the art which makes it possible to produce emulsions. In this respect, reference may be made to formulatory works, such as “Pharmacie Galénique” [Formulatory Pharmaceutical Science], A. Le Hir, published by Masson (8th edition of 2006). [0052] Furthermore, the nanoparticles can also be obtained by the processes described in patent applications EP 0 717 989 A1, WO 2000/71676 A1, WO 2001/64328 A1 and WO 2004/060358 A2. [0053] Patent application WO 2004/060358 A2 specifically describes a process for the preparation of PIT emulsion. [0054] The textile and the monitoring label are respectively impregnated is with the at least one active principle and with the colorant by any technique known in the field of textiles, such as, for example, by dipping, exhaustion bath, spraying or padding. [0055] When the at least one active principle is in the form of nanoparticles, the amount of nanoparticles can be between 10 and 50 g per kg of textile. [0056] In a preferred embodiment of the invention, the impregnation is carried out by dipping at a temperature of between 20° C. and 60° C. [0057] As regards the textile, in addition to the compound of interest and/or active principle, the aqueous solution in which the dipping of the textile is carried out can comprise other additives, such as those chosen from preservatives and/or antibacterials, fillers, antifoaming agents, antistatic agents, stabilizers, antioxidants and/or UV screening agents. The aqueous solution can also comprise flame retardants, plasticizers, pigments and agents which make possible the formation of a protective sheath around the fibers of which the textile is composed, which protective sheath slowly disintegrates on contact with the subject wearing the textile. [0058] The invention also relates to a label for monitoring and/or following the release of at least one active principle impregnated in a first textile, said label being made of a second textile which is impregnated with a colorant, the amount of which is adjusted so that the decolorization of said label is proportional to the release of said at least one active principle. [0059] The invention also relates to a textile article comprising a monitoring label as described above. [0060] The textile article can be chosen from items of clothing, gloves, slippers, underwear, stockings, pantyhose, curtains, cushion or sofa covers, wall textiles, bandages, splints, dressings, compresses, head bandages or masks. [0061] The following examples illustrate the invention without, however, limiting the scope thereof. EXAMPLES [0062] The experimental part is composed of three parts illustrating the present invention: [0063] 1) The preparation of a monitoring label and the monitoring of the release of the colorant with which said monitoring label is impregnated, as a function of the washing operations carried out and as a function of the diluting of the colorant solution carried out before the impregnation of the monitoring label. [0064] 2) The development of a method for extracting a slimming active principle, sterol, in order to be able to precisely determine the remaining amount of this active principle impregnated in the textile after multiple washing operations carried out. [0065] 3) The determination of the appropriate monitoring label which is proportional to the release of a microencapsulated fragrance with which a textile is impregnated. Example 1 [0066] 1) Preparation of a monitoring label: [0067] The impregnation protocol for the preparation of a monitoring label was as follows. [0068] The operation was carried out on monitoring labels made of white textile fibers (as 100% polyamide, nonwoven). Nature of the colorant: a white solid which, dissolved, gives a pink solution, of CAS number: 13473-26-2, and with the chemical structure: [0000] [0069] The colorant was in the form of a nanoemulsion obtained according to the process described in WO 2004/060358 A2. [0070] The amount of colorant present in the nanoemulsion was 0.25 g per 100 g of nanoemulsion. [0071] The nanoemulsion was diluted in water according to a given concentration: ½ or ¼ or ⅛ or 1/16. [0072] The monitoring labels were immersed at 40° C. in one of the abovementioned is dilute solutions. [0073] The impregnation time was 30 minutes. Drying was carried out in a flat position. [0074] Once dried, the various labels were washed up to 20 times, this being carried out according to the standardized protocol of the standard ISO 6330 (standard relating to methods for domestic washing and drying for the purpose of tests on textiles). [0075] After each washing and drying, the color of the label was given a numerical value. [0076] The results obtained are summarized in the following table 1. [0077] The following colors were defined: Fuchsia pink, Fuchsia pink 2 (Lighter pink than Fuchsia pink) Pink, Light pink, Light pink 2 (Lighter pink than Light pink), Pastel pink, Pastel pink 2 (Lighter pink than Pastel pink), Pinkish white. [0000] TABLE 1 Decolorization of the monitoring labels as a function of the dilution of the coloring solution and of the number of washing operations carried out Number of washing operations ½ Dilution ¼ Dilution ⅛ Dilution 1/16 Dilution Control Fuchsia pink Fuchsia Pink Light pink pink 2 1 Washing Pink Pink Light pink Light pink operation 3 Washing Light pink Light pink Light pink Light pink operations 5 Washing Light pink 2 Light pink 2 Light pink Light pink operations 7 Washing Pastel pink Pastel pink Light pink Pastel pink operations 10 Washing Pastel pink 2 Pastel pink 2 Pastel pink Pastel pink operations 15 Washing Pastel pink 2 Pastel pink 2 Pinkish Pinkish white operations white 20 Washing Pastel pink 2 Pastel pink 2 Pinkish Pinkish white operations white Example 2 [0086] 2) Development of a method for the extraction and analysis of a slimming active principle: the sterol. [0087] The sterol was in the form of a nanoemulsion obtained according to the process described in WO 2004/060358 A2. [0088] The sterol was quantitatively determined by reverse-phase liquid chromatography with detection in the ultraviolet at 240 nm. The linearity of the quantitative determination of the sterol in pure solution was confirmed with sterol solutions prepared from the source of the sterol, namely rhodysterol (red alga extract known for its excellent lipolytic properties). [0089] The reagents were as follows: rhodysterol (Batch 6.06.171), a slimming mist SYO1 92V—Placebo (from Cosnessens), a slimming mist SY0192V—comprising 5% of active principle (from Cosnessens), a slimming mist SYO192X—comprising 2% of active principle (from Cosnessens), methanol for chromatography (from VWRI), absolute ethanol for analysis (Carlo Erba). [0096] The chromatography conditions were as follows: stationary phase: column Supelcosil LC18, 5 pm, 250×4.6 mm, mobile phase: methanol, UV detection: 240 nm, flow rate: 1.0 ml/min. [0101] The amount injected was 20 μl. [0102] The analytical time was 30 minutes. [0103] The retention times (depending on its specific conditions) were 12.5 minutes. [0104] Preparation of the solutions: [0105] A sterol mother solution for the quantitative determination (hereinafter abbreviated to MS) was prepared in the following way: A sample W C of approximately 500 mg of mist comprising sterol at 0.075% was introduced, with accuracy, into a 50 ml volumetric flask, dissolved in approximately 40 ml of ethanol and made up to volume with the same solvent. A control Quantitative determination solution was prepared by transferring 2.0 ml of the mother solution (MS) into a 10 ml volumetric flask and making up to the graduation line with absolute ethanol. [0107] A test solution was prepared by introducing half of a pair of shorts (with a weight W T in grams) in well-packed fashion into the bottom of a 1000 ml flask, and also a magnetic bar. [0108] 500 ml, exactly measured, of absolute ethanol were added to the flask, which was subsequently placed under ultrasound for 30 minutes and then stirred magnetically for 20 minutes. [0109] The operations employing ultrasound and magnetic stirring were repeated three times. [0110] An exactly measured amount of 100 ml of the liquid obtained was withdrawn and evaporated to dryness under vacuum at a temperature of approximately 40° C. The evaporation residue was dissolved in 5 ml of absolute ethanol and then filtered through a filter with a porosity of 0.45 μm. [0112] Two injections of 20 μl of the control solution were carried out in order to calculate the mean of the sterol peak areas, i.e. A a . [0113] Two injections of 20 μl of the test solution were carried out in order to calculate the mean of the sterol peak areas, i.e. A T . [0114] The sterol content, expressed in mg per unit of shorts, is calculated according to the formula: [0000] Q = A T A a * 2 * 0.075 * W c 50 * 5 * 100 * WW W T * 500 * 5 100 [0115] A T : is the mean of the sterol peak areas in the test solution, [0116] A a : is the mean of the sterol peak areas in the control solution, [0117] W C : is the sample in mg of the mist comprising 0.075% of sterol, [0118] W T : is the sample in g of shorts, [0119] WW: is the weight in g of the shorts. [0120] Thus, the following quantitative determination was carried out: [0121] WW=50.22212 g [0122] W T =24.86049 g [0123] W C =514 mg [0124] The following peak areas were found: [0125] A T =48470 [0126] A a =61928 [0127] The content (Q) of sterol was thus as follows: [0000] The   content   Q =  48470 61928 × 2 × 0.075 × 514 50 × 5 × 100 × 50.22212 24.66049 × 500 × 5 100 =  0.123   mg  /  shorts [0128] Furthermore, the specificity of the quantitative determination of the sterol was confirmed by comparing the chromatograms: of a control solution of mist devoid of sterol (1), of a control solution of mist comprising sterol (2), of a control solution of rhodysterol (3), of a sample solution obtained after extraction (4). [0133] In the last three solutions, a well-isolated peak with a retention time of the order of 12.5 minutes characteristic of the presence of sterol was indeed encountered. [0134] This thus clearly validated the idea of carrying out the extraction of the sterol by liquid chromatography. [0135] Furthermore, the linearity of the method was confirmed by quantitatively determining the sterol starting from four solutions prepared from rhodysterol. Example 3 [0136] The example below illustrates the exhaustion by washing of microencapsulated compounds of interest and/or active principles attached to cotton fibers and/or textiles. [0137] The compound of interest was a fragrance: linalyl acetate (main compound of lavender), of CAS number: 115-95-7 and with the chemical structure: [0000] [0138] In order for the fragrance to be released from the capsules attached to the fibers, extraction was carried out by accelerated solvent extraction (ASE) with a Dionex device. The solvent chosen was acetone. ASE uses a high pressure and high temperature process which makes it possible to split the membrane of is the capsules and to extract the linalyl acetate. A gas chromatography procedure was then developed in order to be able to quantify the linalyl acetate extracted. The extraction and analytical methods were carried out on the textile, before and after each washing operation. [0139] The following results were obtained: [0000] TABLE 2 Percentage of fragrance extracted from the textile Number of washing operations % Fragrance Control 100 1 Washing operation  70 3 Washing operations 60 5 Washing operations ≈50 7 Washing operations ≈40 10 Washing operations  35 [0140] Among the monitoring labels prepared in example 1, it may be noticed, in the following table 3, that the monitoring label prepared with a ½ dilution follows a decolorization similar to the change in the percentage of fragrance extracted from the textile. [0000] TABLE 3 Comparison of % active principle/decolorization as a function of the number of washing operations Number of washing operations ½ Dilution % Fragrance Control Fuchsia pink 100 1 Washing operation  Pink 70 3 Washing operations Light pink 60 5 Washing operations Light pink 2 ≈50 7 Washing operations Pastel pink ≈40 10 Washing operations  Pastel pink 2 35 [0141] Thus, the monitoring label prepared with ½ dilution might be entirely suitable as monitoring label in the textile impregnated with linalyl acetate microcapsules.

A control and/or monitoring method for the salting-out of at least one active ingredient impregnated in a first textile material characterized in that: a) said first textile material impregnated with said at least one active ingredient is provided, b) a control tag is affixed on the first textile material, and is made from a second textile material at least partially impregnated with a dye, the quantity of which being adjusted in such a way that the discoloration of said tag is proportional to the salting-out of said at least one active ingredient, c) the quantity of the at least one salted-out active ingredient is evaluated by visualizing the discoloration of the said tag. The invention relates to a control and/or monitoring tag of the salting-out of at least one active ingredient impregnated into a textile material.

CROSS-REFERENCE TO RELATED APPLICATION The present application is a continuation-in-part of application Ser. No. 432,277, filed on Jan. 10, 1974 and now abandoned. BACKGROUND OF THE INVENTION With the advent of air pollution requirements, it has been necessary to remove sulfur-containing gaseous contaminants from hot coal gasification effluent gases, some of which (e.g. SO 2 ) have previously been expelled to the atmosphere. Other sulfur-containing gaseous contaminants such as hydrogen sulfides and other sulfides such as CS 2 that are customarily found in such effluent gases, have also had to be removed not only because of corrosion problems they would induce but also because the oxides of sulfur formed during combustion would be a nuisance to coal gas consumers. Heretofore, hot H 2 S containing hot coal gasification gas mixtures have been purified by having had their H 2 S content removed by conventional scrubbing, such as by wet or dry scrubbing, e.g., by caustic scrubbing. The dry method of scrubbing, now largely superseded by the wet method, consisted in the removal of sulfides such as H 2 S through contact with dry iron oxide or hydroxide and subsequent extraction of the spent and reactivated hydroxide with carbon disulfide for recovery of the sulfur. On the other hand, wet scrubbing has simplified considerably the overall coal gas purification through scrubbing of the coal gas with various liquids, e.g. a caustic solution such as a dilute (3%) solution of sodium carbonate. Other wet methods have utilized dilute (1-2%) soda-ash solutions with ferric hydroxide suspended therein; aqueous arsenious oxide in soda ash; cold solutions of organic amines such as 50% aqueous solutions of diethanolamine; sodium phenolate comprising a fairly concentrated solution of phenol in caustic soda; etc. However, wet scrubbing has not proved to be entirely satisfactory since it often involves the need of costly specialized equipment such as absorbers, e.g. bubble-cap or packed absorption towers, heat exchangers, and the like. A significant advantage of the present invention lies in its ability to effect coal gas purification through removal of H 2 S therefrom in a much simpler manner than heretofore afforded by the various scrubbing methods previously utilized. Thus, in accordance with this invention, the H 2 S contamination of hot coal gasification effluent gases can readily be accomplished through use of a nickel-containing material or acceptor at elevated temperatures, thereby obviating the need for costly heat transfer equipment previously associated with scrubbing, which material or acceptor can easily be regenerated by oxidation, e.g. air oxidation. SUMMARY OF THE INVENTION This invention relates to a process for the selective removal of hydrogen sulfide from a mixture of hot coal gasification effluent gases containing same, and, more particularly, relates to a process for the selective removal of hydrogen sulfide from a mixture of hot H 2 S-containing coal gasification effluent gases by reaction of such mixture with a nickel-containing material or acceptor, whereby the nickel reacts with the hydrogen sulfide to form solid compounds from which the nickel content can be regenerated by oxidation and recycled back to the reaction zone for further reaction with more of the H 2 S-containing hot coal gasification effluent gas mixture. DESCRIPTION OF THE PREFERRED EMBODIMENTS In a preferred embodiment of this invention, a suitable coal gas effluent such as the ordinary hot coal gas effluent from a conventional coal gasifier, operated at temperatures upward of 900° F., usually about 1000° F. or above, is passed over a nickel-containing material or acceptor at an elevated temperature in a suitable reactor or reaction zone. The hot coal gasification effluent gases, as utilized herein, may be defined in terms of their comprising a mixture containing hydrogen and carbon monoxide in a ratio of 0.7 to 1.3 volumes of hydrogen per volume of carbon monoxide, along with some carbon dioxide, water vapor, methane, and hydrogen sulfide, the sulfur content being about 0.1 to about 6.0 mole %, usually about 0.1-0.4 mole %. Of course, as will be appreciated by the art, the type of coal that is gasified is not of significance and is intended to include all conventional types of coal that are used in the usual coal gasification processes such as lignite, anthracite, sub-bituminous, ordinary bituminous coal, etc. This is so because the H 2 S concentrations from the coal sources of present conventional processes are relatively of the same order of magnitude, as indicated above, since they ordinarily represent the usual ranges of sulfur content in conventional coals used as fuel. The nickel-containing material or acceptor is preferably one of a nickel-containing: metal, metal alloy such as nickel-aluminum, or other nickel-containing material, or the oxides thereof. Such a material or acceptor can, of course, be supported on an inert carrier of any of the readily available types. Thus, representative examples of carrier materials which can be used as a solid support component of the nickel-containing material or acceptor are the various aluminous and siliceous materials of natural or synthetic origin such as natural and acid treated clays, bauxite, aluminum oxide, activated alumina, kieselguhr, alumina gel, silica gel, silica-alumina gel, magnesia gel, mixed gels, magnesium oxide, chromium oxide, chromite, vanadium oxide, vanadite, magnesium silicate, pumice, kaolin, Carborundum, Alundum, etc. Additional, exemplary support materials include activated carbon. The nickel-containing material or acceptor is preferably nickel. Broadly speaking, the hot coal gasification effluent gaseous stream is preferably passed through a bed of the nickel-containing material or acceptor at a temperature between about 1000° F. and about 1450° F., preferably between about 1050° F. and about 1350° F. However, when the hydrogen content of the effluent is high, it is preferred to conduct treatment of such a high hydrogen content-effluent at temperatures of about 1000° F. to about 1350° F., preferably about 1050° F. to about 1250° F., and most preferably between about 1100° F. to about 1150° F. The hot coal gasification effluent gas is fed into the reaction zone at a temperature close to the desulfurization temperature, thereby keeping said reaction zone in heat balance. As the nickel content of the nickel-containing material or acceptor becomes spent by becoming transformed to solid nickel sulfide compounds, these latter compounds are withdrawn from the bed and replaced with regenerated nickel-containing material, continuously added to the bed. The spent nickel-containing solids are withdrawn into a regeneration zone wherein they are subjected to controlled oxidation with an oxygen-containing gas such as air. In a preferred embodiment, the spent nickel-containing material or acceptor is regenerated by aeration, i.e., by having air blown through the spent nickel-containing bed. By adjustment of the velocity of the hot coal gasification effluent gases fed into the reactor or desulfurizing or reaction zone to the characteristics of the nickel-containing solids, the latter can be maintained in the form of a fluidized bed or suspended in the gases for the time of treatment. Preferably, the regeneration of the nickel-containing material or acceptor is effected at a temperature sufficient to satisfy the equilibrium considerations governing the regeneration reaction as well as the reaction between Ni and SO 2 . Since the hydrogen content of the hot coal gasification effluent is ordinarily high, it is preferable to conduct treatment of such effluent with the nickel-containing material or acceptor at temperatures on the low side of the temperature range set forth above, about 1000° F. to about 1350° F. preferably between about 1050° F. and about 1250° F., most preferably between 1000° F. and 1100°-1150° F. so as to counteract the tendency of hydrogen to form H 2 S. The spent acceptor or nickel-containing material comprising solid compounds of nickel sulfide, upon separation from the hot coal gasification gas effluent, can be regenerated in a separate regeneration zone wherein the NiS compounds can be reacted directly with oxygen from the air by means of aeration wherein air is blown through the spent nickel-containing material or acceptor at temperatures approximating those in the reaction zone, i.e. 1000° F. to 1450° F., preferably about 1000° F. to about 1350° F., and most preferably about 1050° F. to about 1150° F. In the regeneration zone, the solid NiS compounds are reacted with the oxygen of the air to form sulfur dioxide and the free nickel-containing material, and are then separated, with the nickel-containing solids being restored to the reaction zone for further contact with the H 2 S present in the hot coal gasification gaseous effluent newly introduced therein. An example is included herebelow to illustrate conventional coal gasification, in respect of the usual types of conditions employed. The results tabulated below illustrate the state of the art and the quality of the effluent product and its components. Such results are enhanced by application of the essence of the present invention thereto. EXAMPLE______________________________________Fuel-Anthracite or Mildly Caking Bituminous Coals______________________________________ Fuel Fuel Mildly Caking Anthracite Coal Bituminous Coal Oxygen Air Oxygen AirGasifying Medium and Steam and Steam and Steam and Steam______________________________________Typical Compositionat GasifierOutlet - Mole % CO 9.2 13.3 25.7 19.0 CO.sub.2 14.7 13.3 15.8 6.2 H.sub.2 20.1 19.6 32.2 11.7 H.sub.2 O 50.2 10.1 23.1 11.5 CH.sub.4 4.7 5.5 2.4 0.5 C.sub.2 H.sub.6 0.5 nil nil nil N.sub.2 -- 37.5 0.8 51.1 C.sub.2 H.sub.4 -- -- -- -- Others 0.6 0.7 -- --Higher HeatingValue (Dry Basis)BTU/SCF 300 180 275 118______________________________________ A latitude of modification, change, and substitution is intended in the foregoing disclosure, and in some instances some features of the invention will be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the spirit and scope of the invention described herein.

Continuous process for the selective removal of hydrogen sulfide from a mixture of hot coal gasification gases containing hydrogen sulfide by contacting such mixture in a reaction or desulfurizing zone at an elevated temperature with a nickel-containing material whereby the nickel reacts with the hydrogen sulfide to form solid compounds from which the nickel content can be regenerated by oxidation and recycled back to the reaction zone, thereby effectively removing hydrogen sulfide from the hot gas mixture.

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is the US National Stage of International Application No. PCT/EP2009/054306, filed Apr. 9, 2009 and claims the benefit thereof. The International Application claims the benefits of German application No. 10 2008 018 708.9 DE filed Apr. 14, 2008. All of the applications are incorporated by reference herein in their entirety. FIELD OF INVENTION [0002] The invention relates to a process for welding a substrate having a preferred direction. BACKGROUND OF INVENTION [0003] Welding is a repair process which is frequently used to close cracks or to apply material. In this case, a laser is often used as the energy source. The laser welding process is also used to repair directionally solidified components, for example turbine blades or vanes of the largest gas turbines, after they have been used, which possibly have cracks as a result of extraordinarily severe loading. These can be components with grains solidified in columnar form (DS) or else single crystals (SX). [0004] The component therefore has a defined preferred crystallographic direction in the crystal structure. The solidification behavior of the material, which should obtain the same orientation as the substrate during the laser welding, depends on the composition of the alloy, the temperature gradient and the solidification rate. For a defined alloy, there are graphs showing how the structure developed depending on the temperature gradient and the solidification rate. [0005] Nevertheless, grains frequently grow in an undesirable direction. SUMMARY OF INVENTION [0006] It is therefore an object of the invention to overcome this problem. [0007] The object is achieved by a process as claimed in the claims. [0008] The dependent claims list further advantageous measures which can be combined with one another, as desired, in order to obtain further advantages. BRIEF DESCRIPTION OF THE DRAWINGS [0009] FIGS. 1-6 show a substrate during laser remelting, [0010] FIG. 7 shows a gas turbine, [0011] FIG. 8 shows a perspective view of a turbine blade or vane, [0012] FIG. 9 shows a perspective view of a combustion chamber, and [0013] FIG. 10 shows a list of superalloys. [0014] The figures and the description represent only exemplary embodiments of the invention. DETAILED DESCRIPTION OF INVENTION [0015] FIG. 1 is a cross-sectional view of a component 1 , 120 , 130 ( FIGS. 8 , 10 ), 155 ( FIG. 9 ) having a substrate 4 which, in particular in the case of turbine blades or vanes for gas turbines 100 ( FIG. 7 ) or steam turbines, has a superalloy according to FIG. 10 . [0016] The substrate 4 has a directionally solidified structure, i.e. it can consist of columnar grains solidified in columnar form (DS) or of a single crystal (SX). The arrows 7 , 22 indicate the preferred crystallographic directions of the substrate 4 , i.e. of the single crystal or of the columnar grains (e.g.: [001]=7, [010]=22). [0017] The substrate 4 has a crack (not shown). The substrate 4 is therefore melted (remelted) in the region of the crack, where the molten region (melt 19 , FIGS. 3 , 4 ) should again solidify directionally in a DS or SX structure. [0018] The substrate 4 may likewise have a point (excessively thin wall, not shown) which is to be strengthened by build-up welding (i.e. the supply of material is required), in particular laser build-up welding. [0019] FIG. 2 shows a line 10 of a solidification front, which represents a surface and, in the plane of the drawing, shows a transition between a melt 19 and the zone 24 which has already solidified from a melt and also a region 23 still to be remelted. [0020] In the figures, the line 10 always shows only a section of the solidification front. [0021] The substrate 4 moves along a direction 25 from left to right in the drawing, such that the solidification front 10 propagates from right to left in the drawing counter to the direction 25 . [0022] It is likewise possible for only the welding appliance 31 to move instead of the substrate 4 . [0023] The solidification front 10 is then that part of the elliptical line 10 , on the right in FIG. 2 , which comprises the melt 19 . The line 10 is only exemplary. The line 10 may also have other forms. [0024] Depending on the depth t along the direction 28 (perpendicular downward to the surface 16 ) of the line 10 , there are differently oriented temperature gradients 13 , 13 ′, depending on the vicinity of the surface 16 of the substrate 4 . Here, the temperature gradient 13 , 13 ′ is virtually perpendicular on the solidification front 10 . [0025] Proceeding from FIG. 2 , angles Ψ 1 , Ψ 1 ′ and Ψ 2 , Ψ 2 ′ are then additionally shown in FIG. 3 (and also in FIG. 4 ), where Ψ 1 , Ψ 1 ′ are the angles between the preferred direction 7 and the temperature gradients 13 , 13 ′ and Ψ 2 , Ψ 2 ′ are the angles between the temperature gradients 13 , 13 ′ and a second crystallographic direction 22 (perpendicular to the preferred direction 7 ). [0026] Here, the substrate 4 moves from left to right in the drawing. [0027] In FIG. 3 , the direction of dendrite growth is changed during growth from the melt 19 , since Ψ 2 <Ψ 1 holds true at the surface 16 , such that the crystallographic direction 22 directed downward from the surface 16 is energetically promoted, and the dendrites grow in a second crystallographic direction 22 from the surface 16 , such that secondary grains form in the region of the surface. [0028] At a greater depth, it may hold true that Ψ 2 ′>Ψ 1 ′ and the direction 7 is preferred. [0029] The problem first arises when a direction of dendrite growth directed from the surface 16 into the melt 19 is favored at the surface 16 . By definition, epitaxial growth from the surface 16 is not possible, because a substrate which can act as a nucleus for the dendrites is not present there. Instead, the progression of the solid/liquid phase boundary at the surface 16 is realized under these conditions via the formation of secondary arms, tertiary arms, etc. This is too slow compared to the rate of growth of the nuclei before the solidification front. At some point in time, one of these nuclei prevails with respect to the epitaxially grown dendrites, and directions of dendrite growth which are not correlated with those in the substrate 4 are formed. [0030] The problem of epitaxy loss therefore always arises whenever the crystal directions 7 , 22 favored at the surface 16 are not oriented parallel to the surface 16 . These crystal directions 7 , 22 , favored for the dendrite growth, are independent of the direction of movement 25 . However, these crystal directions can be utilized by the dendrites for their growth in two directions. [0031] In order to avoid epitaxy loss, the direction of movement 25 has to be selected in such a manner that of the crystal directions 7 , 22 (here 22 ) favored at the surface 16 on the solidification front 10 , a direction of dendrite growth which has a projection (vectors P 22 , P 7 =projections of 7 , 22 to surface normal {right arrow over (n 0 )}) in the direction of the surface normal {right arrow over (n 0 )}( FIG. 5 ) is initialized. [0032] By selecting the direction of movement 25 in FIG. 4 , specifically from right to left in the drawing, that crystallographic direction, here 22 , which is not directed downward from the surface 16 is preferred. [0033] This applies with preference to the entire solidification front 10 , i.e. the line 10 between the melt pool 19 and the region 24 which has already solidified. [0034] Both of the crystallographic directions 7 , 22 are permissible and desirable. This actually involves the loss of epitaxial growth, which has the effect that the crystal orientation is lost completely in the weld metal ( FIG. 6 : vector P 22 opposed to {right arrow over (n 0 )}= FIG. 3 ). This can be avoided by preventing the promotion of a direction of dendrite growth directed downward from the surface 16 . [0035] FIG. 7 shows, by way of example, a partial longitudinal section through a gas turbine 100 . [0036] In the interior, the gas turbine 100 has a rotor 103 with a shaft 101 which is mounted such that it can rotate about an axis of rotation 102 and is also referred to as the turbine rotor. [0037] An intake housing 104 , a compressor 105 , a, for example, toroidal combustion chamber 110 , in particular an annular combustion chamber, with a plurality of coaxially arranged burners 107 , a turbine 108 and the exhaust-gas housing 109 follow one another along the rotor 103 . [0038] The annular combustion chamber 110 is in communication with a, for example, annular hot-gas passage 111 , where, by way of example, four successive turbine stages 112 form the turbine 108 . [0039] Each turbine stage 112 is formed, for example, from two blade or vane rings. As seen in the direction of flow of a working medium 113 , in the hot-gas passage 111 a row of guide vanes 115 is followed by a row 125 formed from rotor blades 120 . [0040] The guide vanes 130 are secured to an inner housing 138 of a stator 143 , whereas the rotor blades 120 of a row 125 are fitted to the rotor 103 for example by means of a turbine disk 133 . [0041] A generator (not shown) is coupled to the rotor 103 . [0042] While the gas turbine 100 is operating, the compressor 105 sucks in air 135 through the intake housing 104 and compresses it. The compressed air provided at the turbine-side end of the compressor 105 is passed to the burners 107 , where it is mixed with a fuel. The mix is then burnt in the combustion chamber 110 , forming the working medium 113 . From there, the working medium 113 flows along the hot-gas passage 111 past the guide vanes 130 and the rotor blades 120 . The working medium 113 is expanded at the rotor blades 120 , transferring its momentum, so that the rotor blades 120 drive the rotor 103 and the latter in turn drives the generator coupled to it. [0043] While the gas turbine 100 is operating, the components which are exposed to the hot working medium 113 are subject to thermal stresses. The guide vanes 130 and rotor blades 120 of the first turbine stage 112 , as seen in the direction of flow of the working medium 113 , together with the heat shield elements which line the annular combustion chamber 110 , are subject to the highest thermal stresses. [0044] To be able to withstand the temperatures which prevail there, they may be cooled by means of a coolant. [0045] Substrates of the components may likewise have a directional structure, i.e. they are in single-crystal form (SX structure) or have only longitudinally oriented grains (DS structure). [0046] By way of example, iron-based, nickel-based or cobalt-based superalloys are used as material for the components, in particular for the turbine blade or vane 120 , 130 and components of the combustion chamber 110 . [0047] Superalloys of this type are known, for example, from EP 1 204 776 B1, EP 1 306 454, EP 1 319 729 A1, WO 99/67435 or WO 00/44949. [0048] The blades or vanes 120 , 130 may likewise have coatings protecting against corrosion (MCrAlX; M is at least one element selected from the group consisting of iron (Fe), cobalt (Co), nickel (Ni), X is an active element and stands for yttrium (Y) and/or silicon, scandium (Sc) and/or at least one rare earth element, or hafnium). Alloys of this type are known from EP 0 486 489 B1, EP 0 786 017 B1, EP 0 412 397 B1 or EP 1 306 454 A1. [0049] It is also possible for a thermal barrier coating to be present on the MCrAlX, consisting for example of ZrO 2 , Y 2 O 3 -ZrO 2 , i.e. unstabilized, partially stabilized or fully stabilized by yttrium oxide and/or calcium oxide and/or magnesium oxide. [0050] Columnar grains are produced in the thermal barrier coating by suitable coating processes, such as for example electron beam physical vapor deposition (EB-PVD). [0051] The guide vane 130 has a guide vane root (not shown here), which faces the inner housing 138 of the turbine 108 , and a guide vane head which is at the opposite end from the guide vane root. The guide vane head faces the rotor 103 and is fixed to a securing ring 140 of the stator 143 . [0052] FIG. 8 shows a perspective view of a rotor blade 120 or guide vane 130 of a turbomachine, which extends along a longitudinal axis 121 . [0053] The turbomachine may be a gas turbine of an aircraft or of a power plant for generating electricity, a steam turbine or a compressor. [0054] The blade or vane 120 , 130 has, in succession along the longitudinal axis 121 , a securing region 400 , an adjoining blade or vane platform 403 and a main blade or vane part 406 and a blade or vane tip 415 . [0055] As a guide vane 130 , the vane 130 may have a further platform (not shown) at its vane tip 415 . [0056] A blade or vane root 183 , which is used to secure the rotor blades 120 , 130 to a shaft or a disk (not shown), is formed in the securing region 400 . [0057] The blade or vane root 183 is designed, for example, in hammerhead form. Other configurations, such as a fir-tree or dovetail root, are possible. [0058] The blade or vane 120 , 130 has a leading edge 409 and a trailing edge 412 for a medium which flows past the main blade or vane part 406 . [0059] In the case of conventional blades or vanes 120 , 130 , by way of example solid metallic materials, in particular superalloys, are used in all regions 400 , 403 , 406 of the blade or vane 120 , 130 . [0060] Superalloys of this type are known, for example, from EP 1 204 776 B1, EP 1 306 454, EP 1 319 729 A1, WO 99/67435 or WO 00/44949. [0061] The blade or vane 120 , 130 may in this case be produced by a casting process, by means of directional solidification, by a forging process, by a milling process or combinations thereof. [0062] Workpieces with a single-crystal structure or structures are used as components for machines which, in operation, are exposed to high mechanical, thermal and/or chemical stresses. [0063] Single-crystal workpieces of this type are produced, for example, by directional solidification from the melt. This involves casting processes in which the liquid metallic alloy solidifies to form the single-crystal structure, i.e. the single-crystal workpiece, or solidifies directionally. [0064] In this case, dendritic crystals are oriented along the direction of heat flow and form either a columnar crystalline grain structure (i.e. grains which run over the entire length of the workpiece and are referred to here, in accordance with the language customarily used, as directionally solidified) or a single-crystal structure, i.e. the entire workpiece consists of one single crystal. In these processes, a transition to globular (polycrystalline) solidification needs to be avoided, since non-directional growth inevitably forms transverse and longitudinal grain boundaries, which negate the favorable properties of the directionally solidified or single-crystal component. [0065] Where the text refers in general terms to directionally solidified microstructures, this is to be understood as meaning both single crystals, which do not have any grain boundaries or at most have small-angle grain boundaries, and columnar crystal structures, which do have grain boundaries running in the longitudinal direction but do not have any transverse grain boundaries. This second form of crystalline structures is also described as directionally solidified microstructures (directionally solidified structures). [0066] Processes of this type are known from U.S. Pat. No. 6,024,792 and EP 0 892 090 A1. [0067] The blades or vanes 120 , 130 may likewise have coatings protecting against corrosion or oxidation e.g. (MCrAlX; M is at least one element selected from the group consisting of iron (Fe), cobalt (Co), nickel (Ni), X is an active element and stands for yttrium (Y) and/or silicon and/or at least one rare earth element, or hafnium (Hf)). Alloys of this type are known from EP 0 486 489 B1, EP 0 786 017 B1, EP 0 412 397 B1 or EP 1 306 454 A1. [0068] The density is preferably 95% of the theoretical density. [0069] A protective aluminum oxide layer (TGO=thermally grown oxide layer) is formed on the MCrAlX layer (as an intermediate layer or as the outermost layer). [0070] The layer preferably has a composition Co-30Ni-28Cr-8Al-0.6Y-0.7Si or Co-28Ni-24Cr-10Al-0.6Y. In addition to these cobalt- based protective coatings, it is also preferable to use nickel-based protective layers, such as Ni-10Cr-12Al-0.6Y-3Re or Ni-12Co-21Cr-11Al-0.4Y-2Re or Ni-25Co-17Cr-10Al-0.4Y-1.5Re. [0071] It is also possible for a thermal barrier coating, which is preferably the outermost layer and consists for example of ZrO 2 , Y 2 O 3 -ZrO 2 , i.e. unstabilized, partially stabilized or fully stabilized by yttrium oxide and/or calcium oxide and/or magnesium oxide, to be present on the MCrAlX. [0072] The thermal barrier coating covers the entire MCrAlX layer. Columnar grains are produced in the thermal barrier coating by suitable coating processes, such as for example electron beam physical vapor deposition (EB-PVD). [0073] Other coating processes are possible, for example atmospheric plasma spraying (APS), LPPS, VPS or CVD. The thermal barrier coating may include grains that are porous or have micro-cracks or macro-cracks, in order to improve the resistance to thermal shocks. The thermal barrier coating is therefore preferably more porous than the MCrAlX layer. [0074] Refurbishment means that after they have been used, protective layers may have to be removed from components 120 , 130 (e.g. by sand-blasting). Then, the corrosion and/or oxidation layers and products are removed. If appropriate, cracks in the component 120 , 130 are also repaired. This is followed by recoating of the component 120 , 130 , after which the component 120 , 130 can be reused. [0075] The blade or vane 120 , 130 may be hollow or solid in form. [0076] If the blade or vane 120 , 130 is to be cooled, it is hollow and may also have film-cooling holes 418 (indicated by dashed lines). [0077] FIG. 9 shows a combustion chamber 110 of a gas turbine. The combustion chamber 110 is configured, for example, as what is known as an annular combustion chamber, in which a multiplicity of burners 107 , which generate flames 156 , arranged circumferentially around an axis of rotation 102 open out into a common combustion chamber space 154 . For this purpose, the combustion chamber 110 overall is of annular configuration positioned around the axis of rotation 102 . [0078] To achieve a relatively high efficiency, the combustion chamber 110 is designed for a relatively high temperature of the working medium M of approximately 1000° C. to 1600° C. To allow a relatively long service life even with these operating parameters, which are unfavorable for the materials, the combustion chamber wall 153 is provided, on its side which faces the working medium M, with an inner lining formed from heat shield elements 155 . [0079] On the working medium side, each heat shield element 155 made from an alloy is equipped with a particularly heat-resistant protective layer (MCrAlX layer and/or ceramic coating) or is made from material that is able to withstand high temperatures (solid ceramic bricks). [0080] These protective layers may be similar to the turbine blades or vanes, i.e. for example MCrAlX: M is at least one element selected from the group consisting of iron (Fe), cobalt (Co), nickel (Ni), X is an active element and stands for yttrium (Y) and/or silicon and/or at least one rare earth element or hafnium (Hf). Alloys of this type are known from EP 0 486 489 B1, EP 0 786 017 B1, EP 0 412 397 B1 or EP 1 306 454 A1. [0081] It is also possible for a, for example, ceramic thermal barrier coating to be present on the MCrAlX, consisting for example of ZrO 2 , Y 2 O 3 -ZrO 2 , i.e. unstabilized, partially stabilized or fully stabilized by yttrium oxide and/or calcium oxide and/or magnesium oxide. [0082] Columnar grains are produced in the thermal barrier coating by suitable coating processes, such as for example electron beam physical vapor deposition (EB-PVD). [0083] Other coating processes are possible, e.g. atmospheric plasma spraying (APS), LPPS, VPS or CVD. The thermal barrier coating may include grains that are porous or have micro-cracks or macro-cracks, in order to improve the resistance to thermal shocks. [0084] Refurbishment means that after they have been used, protective layers may have to be removed from heat shield elements 155 (e.g. by sand-blasting). Then, the corrosion and/or oxidation layers and products are removed. If appropriate, cracks in the heat shield element 155 are also repaired. This is followed by recoating of the heat shield elements 155 , after which the heat shield elements 155 can be reused. [0085] Moreover, a cooling system may be provided for the heat shield elements 155 and/or their holding elements, on account of the high temperatures in the interior of the combustion chamber 110 . The heat shield elements 155 are then, for example, hollow and may also have cooling holes (not shown) opening out into the combustion chamber space 154 .

Welding repairs are often carried out on directionally solidified components that nevertheless do not possess the desired crystallographic surface alignment, which reduces mechanical strength. The method provided selects the direction of travel depending on the crystallographically preferred direction of the substrate such that no more misorientations occur. A laser beam may be used for remelting.

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] The present application claims the benefit of prior U.S. Provisional Application No. 61/030,307, filed Feb. 21, 2008, which is hereby incorporated by reference. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0002] The invention was made with U.S. Government support under contract no. NIH/NCRR 1 P20 RR021970 (01) awarded by the National Institutes of Health. The U.S. Government has certain rights in the invention. THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT [0003] Not applicable. INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON COMPACT DISC [0004] The Sequence Listing, which is a part of the present disclosure and is submitted in conformity with 37 CFR 1.821-1.825, includes a computer readable form and a written sequence listing comprising nucleotide and/or amino acid sequences of the present invention. The sequence listing information recorded in computer readable form (created 19 Feb. 2009; filename: SEQUENCE LISTING.txt; size: 32.2 KB; size on disk: 33.0 KB) is identical to the written sequence listing below. The subject matter of the Sequence Listing is incorporated herein by reference in its entirety. BACKGROUND OF THE INVENTION [0005] 1. Field of the Invention [0006] The present invention is related to [subj matter under 424 definition] which subject matter contains a protein or its reaction product (e.g., peptides, etc.) wherein the protein molecule is not degrated to the constitutent amino acids. More specifically, the invention is related to subject matter wherein a peptide chain has 25 or more peptide units in an uninterrupted chain. In particular, the present invention is related to recombinant human (“rh”) prosaposin (PSAP) and rh-Saposin C, and to cells useful for expressing rh-PSAP and rh-Saposin C. [0007] 2. Description of Related Art [0008] Prosaposin (PSAP; SEQ ID NO:1) is a highly conserved glycoprotein with 524 amino acids and an approximate molecular weight of 65 to 72 kilodaltons (kDa). See, e.g., Kishimoto Y, Hiraiwa M, O'Brien J S. Saposins: structure, function, distribution, and molecular genetics. J Lipid Res. 33, 1255-1267, 1999; PubMed ID: 1402395. PSAP is the precursor of four small lysosomal proteins (Saposin A, SEQ ID NO:2; Saposin B, SEQ ID NO:3; Saposin C, SEQ ID NO:4; and Saposin D, SEQ ID NO:5, each between 8 and 13 kDa) that are required for intracellular degradation of certain sphingolipids. See Kishimoto Y, 1999. Proteolytic cleavage of PSAP precursor, mediated by lysosomal cysteine protease-cathepsin D, leads to individual mature saposin proteins (acidic glycoproteins). See Kishimoto Y, 1999. PSAP and saposin proteins also exist as soluble extracellular mature proteins in tissue culture supernatant, serum, prostatic secretions, cerebrospinal fluid, seminal fluid, milk and serum. See, e.g., Morimoto S, Yamamoto Y, O'Brien J S, Kishimoto Y. Determination of saposin proteins (sphingolipid activator proteins) in human tissues. Anal Biochem. 190, 154-157, 1990; PubMed ID: 2127157. Morales C R, El-Alfy M, Zhao Q, Igdoura S A. Expression and tissue distribution of rat sulfated glycoprotein-1 (prosaposin). J Histochem Cytochem. 44, 327-337, 1996; PubMed ID: 8601692. [0009] PSAP and individual saposin proteins are expressed by a wide variety of cell types originating from ectodermal, mesodermal, and endodermal germ layers including but not limited to lung, skin, fibroblast, stromal cells, bone, smooth muscle, skeletal muscle, cardiac muscle, placenta, red and white blood cells, pancreas, placenta, lymphoreticular system (spleen, thymus, liver), micro and macrovascular system, genitourinary system (e.g., prostate, testes, seminal vesicles), central and peripheral nervous system, etc. See, e.g., Kishimoto Y, 1999. Morimoto S, 1990. Koochekpour S. PSAP (Prosaposin (variant Gaucher disease and variant metachromatic leukodystrophy). Atlas Genet Cytogenet Oncol Haematol. 10, 370-384, 2006; available at: http://AtlasGeneticsOncology.org/Genes/PSAPID42980ch10q22.html. PSAP and saposins are predominantly expressed in neuroglial-derived tissues as compared to all other normal cell types in the mammalian system. PSAP is overexpressed in a number of malignant or metastatic cell types derived from prostate, breast, lung, brain, and lymphoid tissues. See, e.g., Campana W M, O'Brien J S, Hiraiwa M, Patton S. Secretion of prosaposin, a multifunctional protein, by breast cancer cells. Biochim Biophys Acta. 1427, 392-400, 1999; PubMed ID: 10350655. Koochekpour S, Zhuang, Yu-Jun, Beroukhim R, Hssieh G L, Hofer M D, Zhau H E, Hiraiwa M, Pattan D, Ware J L, Luftig R, Sandhoff K, Sawyers C L, Pienta K J, Rubin M A, Vessella R L, Sellers W R, and Sartor O. Amplification and Overexpression of Prosaposin in Prostate Cancer and Other Malignant Cells. Genes, Chromosomes & Cancer. 44, 351-364, 2005; PubMed ID: 16080200. [0010] Prosaposin is a bi-functional molecule. As the precursor of intracellular lysosomal saposin proteins, it is involved in sphingolipid hydrolysis activity, as a secreted soluble protein, it has neurotrophic activities. See, e.g., O'Brien J S, Carson G S, Seo H C, Hiraiwa M, Kishimoto Y. Identification of prosaposin as a neurotrophic factor. Proc Natl Acad Sci USA. 91, 95963-95966, 1994; PubMed ID: 7937812. O'Brien J S, Carson G S, Seo H C, Hiraiwa M, Weiler S, Tomich J M, Barranger J A, Kahn M, Azuma N, Kishimoto Y. Identification of the neurotrophic factor sequence of prosaposin. FASEB J. 9, 681-685, 1995; PubMed ID: 7768361. Campana W M Hiraiwa M, Addison K C, O'Brien J S. Induction of MAPK phosphorylation by prosaposin and prosaptide in PC12 cells. Biochem Biophys Res Commun. 229, 706-712, 1996; PubMed ID: 8954961. Hiraiwa M, Taylor E M, Campana W M, Darin S J, O'Brien J S. Cell death prevention, mitogen-activated protein kinase stimulation, and increased sulfatide concentrations in Schwann cells and oligodendrocytes by prosaposin and prosaptides. Proc Natl Acad Sci USA. 94, 4778-4781, 1997; PubMed ID: 9114068. Campana W M, Hiraiwa M, O'Brien J S. Prosaptide activates the MAPK pathway by a G-protein-dependent mechanism essential for enhanced sulfatide synthesis by Schwann cells. FASEB J. 12, 307-314, 1998; PubMed ID: 9506474. Campana W M, Darin S J, O'Brien J S. Phosphatidylinositol 3-kinase and Akt protein kinase mediate IGF-I- and prosaptide-induced survival in Schwann cells. J Neurosci Res. 57, 332-341, 1999; PubMed ID: 10412024. Misasi R, Sorice M, Di Marzio L, Campana N M, Molinari S, Cifone M G, Pavan A, Pontieri G M, O'Brien J S. Prosaposin treatment induces PC12 entry in the S phase of the cell cycle and prevents apoptosis: activation of ERKs and sphingosine kinase. FASEB J. 15, 467-474, 2001; PubMed ID: 11156962. Morales C R, Badran H. Prosaposin ablation inactivates the MAPK and Akt signaling pathways and interferes with the development of the prostate gland. Asian J. Androl. 5, 57-63, 2003; PubMed ID: 12647005. Koochekpour S, Sartor O, Lee T J, Zieske A, Patten D Y, Hiraiwa M, Sandhoff K, Remmel N, Minokadeh A. Prosaptide TX14A stimulates growth, migration, and invasion and activates the Raf-MEK-ERK-RSK-Elk-1 signaling pathway in prostate cancer cells. Prostate. 61, 114-123, 2004; PubMed ID: 15305334. Lee T J, Sartor O, Luftig R B, Koochekpour S. Saposin C promotes survival and prevents apoptosis via PI3K/Akt-dependent pathway in prostate cancer cells. Mol. Cancer. 3, 31-44, 2004; PubMed ID: 15548330. Koochekpour S, Sartor O, Hiraiwa M, Lee T J, Rayford W, Remmel N, Sandhoff K, Minokadeh A, Patten D Y. Saposin C stimulates growth and invasion, activates p42/44 and SAPK/JNK signaling pathways of MAPK and upregulates uPA/uPAR expression in prostate cancer and stromal cells. Asian J. Androl. 7, 147-158, 2005; PubMed ID: 15897971. Huwiler A, Kolter T, Pfeilschifter J, Sandhoff K. Physiology and pathophysiology of sphingolipid metabolism and signaling. Biochim Biophys Acta. 1485, 63-99, 2000; PubMed ID: 10832090. Column chromatography data indicated the formation of stable complexes between PSAP/saposins and several gangliosides. It has been suggested that PSAP functions as a sphingolipid binding protein and on the cell surface, complex formation between PSAP and gangliosides may suggests a role for this molecule in ganglioside function. Saposins A-D function as co-activator proteins for intracellular lysosomal degradation of sphingolipids. See, e.g., Qi X, Grabowski G A. Molecular and cell biology of acid beta-glucosidase and prosaposin. Prog Nucleic Acid Res Mol. Biol. 66, 203-239, 2001; PubMed ID: 11051765. Sandhoff K, Kolter T. Biosynthesis, and degradation of mammalian glycosphingolipids. Philos Trans R Soc Lond B Biol Sci. 358, 847-861, 2003; PubMed ID: 12803917. Saposin A and C are involved in hydrolysis of glucosylceramide and galactosylceramide. Saposin B stimulates galacto-cerebroside sulfate hydrolysis, GM1 ganglioside, and globotriaosylceramide. Saposin C is the activator of sphingomyelin phosphodiesterase. While several members of CD1 proteins are involved in lipid presentation to T cells, prosaposin-deficient mice exhibit certain defects in CD1d-mediated antigenic presentation, suggesting that saposins are involved in mobilization of lipid monomers from the lysosomal membrane and their association with CD1d. In addition, prosaposin-deficient fibroblasts transfected with another member of CD1 family (CD1b) also failed to activate lipid-specific T lymphocytes. See, e.g., Kang S J, Cresswell P. Saposins facilitate CD1d-restricted presentation of an exogenous lipid antigen to T cells. Nat. Immunol. 5, 175-181, 2004; PubMed ID: 14716312. Winau F, Schwierzeck V, Hurwitz R, Remmel N, Sieling P A, Modlin R L, Porcelli S A, Brinkmann V, Sugita M, Sandhoff K, Kaufmann S, Schaible U E. Saposin C is required for lipid presentation by human CD1b. Nat. Immunol. 5, 169-174, 2004. Erratum in: Nat. Immunol. 5, 344, 2004; PubMed ID: 14716313. Zhou D, Cantu C 3rd, Sagiv Y, Schrantz N, Kulkarni A B, Qi X, Mahuran D J, Morales C R, Grabowski G A, Benlagha K, Savage P, Bendelac A, Teyton L. Editing of CD1d-bound lipid antigens by endosomal lipid transfer proteins. Science. 303, 523-527, 2004; PubMed ID: 14684827. Prosaposin's bi-functional nature may be suggestive of potential implications for Saposin C or perhaps PSAP in the recognition of tumor antigens. [0011] Several reports have identified in vitro or in vivo neurotrophic/neuroprotective activities for PSAP or Saposin C. In addition, a number of linear 5 to 22 amino acid sequences called prosaptides (e.g., D5, TX14A) located at the amino terminal region of Saposin C domain of PSAP demonstrate in vitro and/or in vivo neurotrophic activities. See, e.g., Henseler M, Klein A, Glombitza G J, Suziki K, Sandhoff K. Expression of the three alternative forms of the sphingolipid activator protein precursor in baby hamster kidney cells and functional assays in a cell culture system. J Biol. Chem. 271, 8416-8423, 1996; PubMed ID: 8626540. Kotani Y, Matsuda S, Wen T C, Sakanaka M, Tanaka J, Maeda N, Kondoh K, Ueno S, Sano A. A hydrophilic peptide comprising 18 amino acid residues of the prosaposin sequence has neurotrophic activity in vitro and in vivo. J. Neurochem. 66, 2197-2200, 1996; PubMed ID: 8780053. The neurotrophic activities of PSAP or its biologically active molecular derivatives (i.e., Saposin C, prosaptides) include growth, development, and maintenance of the peripheral and central nervous systems, neuronal regeneration and plasticity, stimulation of neurite outgrowth, attenuation of loss of muscle mass following nerve injury, stimulation of neuroblastoma cell proliferation, protection of neurons from programmed cell-death (apoptosis), and activation of cell survival signaling pathways such (but not limited to) as MAPK and PI3K/Akt pathways. [0012] By using immunohistochemical staining, intense staining of PSAP was observed in adult rat skeletal, smooth, and cardiac muscle cells with normal innervation. See e.g., Rende M, Brizi E, Donato R, Provenzano C, Bruno R, Misisin A P, Garrett R S, Calcutt N A, Campana W M, O'Brien J S. Prosaposin is immunolocalized to muscle and prosaptides promote myoblast fusion and attenuate loss of muscle mass after nerve injury. Muscle Nerve. 24, 799-808, 2001; PubMed ID: 11360264. Following nerve injury and muscle denervation, PSAP immunostaining was decreased. These data suggest that, in addition to neurotrophic activities, PSAP or its active molecular derivatives has myotrophic activity. [0013] Overall, PSAP, Saposin C, and PSAP-originated oligopeptides demonstrate a number of therapeutic applications, including promoting biofunctional recovery following toxic or physical injury to nervous system, myocardial hypoxic injury, and degenerative or inherited diseases of central or peripheral nervous system. See, e.g., Jolivalt C G, Ramos K M, Herbetsson K, Esch F S, Calcutt N A. Therapeutic efficacy of prosaposin-derived peptide on different models of allodynia. Pain 121, 14-21, 2006; PubMed ID: 16480831. Wagner R, Myers R R, O'Brien, J S. Prosaptide prevents hyperalgesia and reduces peripheral TNFR1 expression following TNF nerve injection. Neuroreport. 9, 2827-2831, 1998; PubMed ID: 9760128. Campana W M, Mohiuddin L, Misasi R, O'Brien J S, Calcutt N A. Prosaposin-derived peptides enhanced sprouting of sensory neurons in vitro and induced sprouting at motor endplates in vivo. J Peripher Nerv Syst. 5, 126-130, 2000; PubMed ID: 11442168. See also: U.S. Pat. No. 5,571,787, issued 5 Nov. 1996. In addition, by inducing neurite outgrowth and stimulating myelination, PSAP, Saposin C, and PSAP-derived peptides are able to inhibit and reduce the consequences of demyelinating diseases. See, e.g., Hiraiwa M, Campana W M, Mizisin A P, Mohiuddin L, O'Brien J S. Prosaposin: a myelinotrophic protein that promotes expression of myelin constituents and is secreted after nerve injury. Glia. 26, 353-360, 1999; PubMed ID: 10383054. [0014] In malignant cells and tissues, several classic reports have indicated a pluripotent regulatory role for Saposin C and PSAP in prostate cancer, with potential involvement in prostate carcinogenesis or progression toward metastatic or androgen-independent state. In addition, under serum-starvation stress, PSAP and/or its active molecular derivatives (Saposin C or TX14A): a) stimulate prostate cancer cell growth, motility, and invasion; b) upregulate proteolytic enzyme uPA/uPAR expression; c) activate the p42/44 MAPK (Raf-MEK-ERK-RSK-Elk-1 signaling cascade), p38 MAPK, and SAPK/JNK family members of the MAPK superfamily and PI3K/Akt signaling pathways; and d) protect cells from apopototic cell death induction by etoposide via modulation of caspase-3, -7, and -9 expression/activity and/or the PI3K/Akt signaling pathway activation. Although several reports have indicated a potential role for PSAP in a variety of cancers (e.g., breast, pancreas, brain, lung, lymphoma) in general, the expression and biological significance of PSAP or Saposin C in cancer biology requires further investigation. [0015] Deficiencies of PSAP and/or saposins B, C, or D are reported to be responsible for a number of clinical diseases. The clinical features in patients with total PSAP deficiency (combined SAP deficiency) are reported to be similar to those in Gaucher disease type 2, which present with acute infantile neuronopathic symptoms, abnormally large visceral organs, deteriorating general physical condition, and death in the first two years of life. Saposin A deficiency as a disease entity has not yet been reported. However, mice with mutated saposin A demonstrate a phenotype similar to late-onset Krabbe disease. Patients with saposin B deficiency show clinical symptoms similar to those associated with Metachromatic leukodystrophy (MLD). Saposin C deficient patients present with clinical findings similar to Gaucher disease type 3. Saposin D mutation in a mouse model has shown progressive polyuria and ataxia and accumulation of ceramide in brain and kidney. Accumulation of saposins (up to 80-fold over normal levels) are detected in spleen, liver, and brain of individuals affected with lysosomal storage diseases (LSD) such as Gaucher disease, Niemann-Pick disease (type 1), fucosidosis, Tay-Sachs disease, and Sandhoff disease. Analysis of plasma levels of saposins in patients with LSD disorders often reveals an increase in saposin A-D levels. [0016] Total prosaposin deficiency leads to a lethal phenotype in both humans and mice. Mice with homozygous inactivation of prosaposin gene (PSAP−/−) demonstrated clinicopathologic signs similar those of human patients with total PSAP deficiency. Among these features was intrauterine or early neonatal death in PSAP−/− mice. In other mice, severe developmental abnormalities in the nervous system and male reproductive system was detected. Neuroembryological developmental abnormalities presented as muscular weakness, trembling or shakiness of head, and ataxia of the limbs and progressed to severe weakness and shaking of head and trunk. After 4 weeks they developed seizures and persistent tonic epilepsy, and finally died at the age of 35 days. Evidence of lysosomal storage disease was also detected by abnormal accumulation of ceramide in brain, liver, and kidney, and storage of gangliosides and ceramide and hypomyelination of the brain. BRIEF SUMMARY OF THE INVENTION [0017] The present invention features, in one aspect, a cell transfected with a mammalian expression vector, wherein said vector provides for expression of recombinant human (“rh”) PSAP, and wherein said rh-PSAP is extracellularly secreted. In a preferred embodiment of this aspect, the cell is a CHO-K1 cell, and the CHO-K1 cell is stably transfected. Also preferably, in this embodiment, the vector bears, in 5′ to 3′ direction, an Ig kappa-chain V-J2-C signal peptide sequence, SEQ ID NO:6, and a hexa-histidine epitope. Preferably, the vector is a pSecTag2 vector into which SEQ ID NO:6 has been cloned. More preferably, the vector is SEQ ID NO:8. [0018] The present invention features, in another aspect, a cell transfected with a mammalian expression vector, wherein said vector provides for expression of recombinant human (“rh”) Saposin C, and wherein said rh-Saposin C is extracellularly secreted. In a preferred embodiment of this aspect, the cell is a CHO-K1 cell, and the CHO-K1 cell is stably transfected. Also preferably, in this embodiment, the vector bears, in 5′ to 3′ direction, an Ig kappa-chain V-J2-C signal peptide sequence, SEQ ID NO:7, and a hexa-histidine epitope. Preferably, the vector is a pSecTag2 vector into which SEQ ID NO:7 has been cloned. More preferably, the vector is SEQ ID NO:9. [0019] In another aspect, the present invention features an isolated recombinant human PSAP comprising the amino acid sequence of SEQ ID NO:17. Preferably, in this aspect, the isolated rh-PSAP is an N-linked glycoprotein and bears a C-terminal 6×His epitope. Even more preferably, in this aspect, the isolated rh-PSAP is a sialylated N-linked glycoprotein and bears a C-terminal 6×His epitope. [0020] In another aspect, the present invention features an isolated recombinant human Saposin C comprising the amino acid sequence of SEQ ID NO:18. Preferably, in this aspect, the isolated rh-Saposin C is an N-linked glycoprotein and bears a C-terminal 6×His epitope. Even more preferably, in this aspect, the isolated rh-Saposin C is a sialylated N-linked glycoprotein and bears a C-terminal 6×His epitope. BRIEF DESCRIPTION OF THE DRAWINGS [0021] For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements. [0022] FIG. 1 is a schematic representation of rh-PSAP and rh-Saposin C expression vectors. The rh-PSAP (SEQ ID NO:6) or rh-Saposin C (SEQ ID NO:7) cDNA sequence was cloned into the SfiI and XhoI sites of pSecTag2A vector in frame with the N-terminal Ig-kappa leader sequence under the control of human cytomegalovirus (CMV) immediate-early promoter. [0023] FIG. 2 is a Western blot analysis of rh-PSAP expression in transiently-transfected human embryonic kidney (HEK) 293T/17 cells. 293T/17 cells were transiently transfected with different rh-PSAP expression vectors. For each construct, 10 μg of supernatant protein was separated in a 4-20% gradient polyacrylamide gel and transferred to PVDF membrane. The membrane was blotted with mouse anti-PSAP antibody. As a positive control, we used 2 μl of purified human milk PSAP. 293T/17 transfected clones with empty vectors were used for comparison. Solid arrow shows PSAP protein. [0024] FIG. 3 is a Western blot analysis of rh-PSAP and rh-Saposin C expression in stably-transfected CHO-K1 clones. For each stable clone, 10 μg of supernatant protein was separated in a 4-20% gradient polyacrylamide gel and transferred to PVDF membrane. The membrane was blotted with goat anti-Saposin C polyclonal antibody, which can also detect PSAP. PC3 supernatant was used as control for native human PSAP. Solid arrows show rh-PSAP or rh-Saposin C. Dashed arrows around 30 and 55 kDa show cleaved PSAP protein products. [0025] FIG. 4 shows SDS-PAGE and Coomassie blue staining analysis for rh-PSAP and rh-Saposin C expression and purification. 40 μl of culture supernatant or 20 μl imidazole washing or elution fraction of rh-PSAP and rh-Saposin C was separated in 4-20% tris-glycine gel. Solid arrow indicate rh-PSAP (˜70 kDa) or rh-Saposin C (˜10 kDa). [0026] FIG. 5 shows SDS-PAGE and silver staining of final purified rh-PSAP and rh-Saposin C. 2 μg rh-PSAP and 0.1 μg bovine serum albumin (BSA) was separated in 4-20% gel (A). Various amount of baculovirus-infected insect cells expressed rh-Saposin C was separated in 10-20% gel. Solid arrows indicate rh-Saposin C (˜10 kDa) or rh-PSAP (˜70 kDa). Dashed arrows indicate extracellularly cleaved products of rh-PSAP protein. [0027] FIG. 6 shows a Western blot analysis of final purified rh-PSAP and rh-Saposin C Various amounts of purified rh-PSAP were separated in 4-20% gel and blotted with mouse anti-PSAP antibody. For Saposin C, various amounts of rh-Saposin C (200-400 ng) were separated in a 10-20% gradient gel and blotted with goat anti-Saposin C antibody. Solid arrows indicate rh-Saposin C (˜10 kDa) or rh-PSAP (˜70 kDa). Dashed arrows indicate the presence of extracellularly cleaved products of rh-PSAP protein. [0028] FIG. 7 illustrates the stimulation of BrdU incorporation as an indicator of cell proliferation by various concentrations of rh-PSAP, or rh-Saposin C, indicating that both pSecTag2A-recombinant proteins are biologically active in mammalian cell types (i.e., PC-3—ATCC No. CRL-1435—and PrSt—prostate stromal—cells). Baculovirus-expressed rh-Saposin C was used as a positive control for cell growth. [0029] FIG. 8 illustrates the stimulation of cell migration by various concentrations of rh-Saposin C and rh-PSAP on prostate stromal and cancer cell line, indicating that these purified proteins are biologically active. Baculovirus-expressed recombinant Saposin C was used a positive (active) control. DETAILED DESCRIPTION OF THE INVENTION [0030] Before the subject invention is further described, it is to be understood that the invention is not limited to the particular embodiments of the invention described below, as variations of the particular embodiments may be made and still fall within the scope of the appended claims. It is also to be understood that the terminology employed is for the purpose of describing particular embodiments, and is not intended to be limiting. Instead, the scope of the present invention will be established by the appended claims. [0031] In this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural reference unless the context clearly dictates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this invention belongs. [0032] In the following description, terms relating to recombinant DNA technology are used. The following definitions are provided to give a clear understanding of the specification and appended claims. [0033] As used herein, the term “PSAP” means prosaposin, and the term “rh-PSAP” means recombinant human prosaposin. [0034] By “gene” is meant a nucleic acid (e.g., deoxyribonucleic acid, or “DNA”) sequence that comprises coding sequences necessary for the production of a polypeptide or precursor (e.g., messenger RNA, or “mRNA”). The polypeptide may be encoded by a full length coding sequence or by any portion of the coding sequence, so long as the desired activity or functional properties (e.g., enzymatic activity, ligand binding, signal transduction, etc.) are retained. The term also encompasses the coding region of a structural gene and the sequences located adjacent to the coding region on both the 5′ and 3′ ends, for a distance of about 1 kb on either end, such that the gene is capable of being transcribed into a full-length mRNA. The sequences located 5′ of the coding region and which are present on the mRNA are referred to as 5′ untranslated sequences, and form the 5′ untranslated region (5′ UTR). The sequences located 3′ or downstream of the coding region and which are present on the mRNA are referred to as 3′ non-translated sequences, and form the 3′ untranslated region (3′ UTR). The term “gene” encompasses both cDNA and genomic forms of a gene. The genomic form or clone of a gene usually contains the coding region interrupted with non-coding sequences termed “introns” (also called “intervening regions” or “intervening sequences”). Introns are segments of a gene which are transcribed into nuclear RNA (hnRNA); introns may contain regulatory elements such as enhancers. Introns are removed or “spliced out” from the nuclear or primary transcript, and therefore are absent from the mRNA transcript. mRNA functions during translation to specify the sequence or order of amino acids in a nascent polypeptide. [0035] By “nucleotide” is meant a monomeric structural unit of nucleic acid (e.g., DNA or RNA) consisting of a sugar moiety (a pentose: ribose, or deoxyribose), a phosphate group, and a nitrogenous heterocyclic base. The base is linked to the sugar moiety via a glycosidic bond (at the 1′ carbon of the pentose ring) and the combination of base and sugar is called a nucleoside. When the nucleoside contains a phosphate group bonded to the 3′ or 5′ position of the pentose, it is referred to as a nucleotide. When the nucleotide contains one such phosphate group, it is referred to as a nucleotide monophosphate; with the addition of two or three such phosphate groups, it is called a nucleotide diphosphate or triphosphate, respectively. The most common, nucleotide bases are derivatives of purine or pyrimidine, with the most common purines being adenine and guanine, and the most common pyrimidines being thymidine, uracil, and cytosine. A sequence of operatively linked nucleotides is typically referred to herein as a “base sequence” or “nucleotide sequence” or “nucleic acid sequence,” and is represented herein by a formula whose left-to-right orientation is in the conventional direction of 5′-terminus to 3′-terminus. A “test nucleic acid sequence” is a nucleic acid sequence used according to the methods of the present invention to measure or test interaction between said nucleic acid sequence and a protein. The test nucleic acid sequence may be a genomic DNA fragment. [0036] DNA molecules are said to have “5′ ends” and “3′ ends” because mononucleotides are joined to make oligonucleotides in a manner such that the 5′ phosphate of one mononucleotide pentose ring is attached to the 3′ oxygen of its neighbor in one direction, via a phosphodiester linkage. Therefore, an end of an oligonucleotide is referred to as the “5′ end” if its 5′-phosphate is not linked to the 3′ oxygen of a mononucleotide pentose ring. Alternatively, it is the “3′ end” if its 3′ oxygen is not linked to a 5′ phosphate of a subsequent mononucleotide pentose ring. These ends are also referred to as “free” ends because they are not linked to upstream or downstream mononucleotides, respectively. A double stranded nucleic acid molecule may also be said to have 5′- and 3′ ends, wherein the “5′” refers to the end containing the accepted beginning of the particular region, gene, or structure, and the “3′” refers to the end downstream of the 5′ end. A nucleic acid sequence, even if internal to a larger oligonucleotide, may also be said to have 5′ and 3′ ends, although these ends are not free ends. In such a case, the 5′ and 3′ ends of the internal nucleic acid sequence refer to the 5′ and 3′ ends that said fragment would have were it isolated from the larger oligonucleotide. In either a linear or circular DNA molecule, discrete elements may be referred to as being “upstream” or 5′ of the “downstream” or 3′ elements. Ends are said to “compatible” if: a) they are both blunt or contain complementary single strand extensions (such as that created after digestion with a restriction endonuclease); and b) at least one of the ends contains a 5′ phosphate group. Compatible ends are therefore capable of being ligated by a double stranded DNA ligase (e.g., T4 DNA ligase) under standard conditions. Nevertheless, blunt ends may also be ligated. [0037] By “promoter” is meant a DNA sequence usually found at the 5′ region of a gene, proximal to the start codon. Transcription of an adjacent gene is initiated at the promoter region. If the promoter is an inducible promoter, the rate of transcription increases in response to an inducing agent. [0038] By “operably linked” is meant that nucleic acid sequences or proteins are operably linked when placed into a functional relationship with another nucleic acid sequence or protein. For example, a promoter sequence is operably linked to a coding sequence if the promoter promotes transcription of the coding sequence. As a further example, a repressor protein and a nucleic acid sequence are operably linked if the repressor protein binds to the nucleic acid sequence. Additionally, a protein may be operably linked to a first and a second nucleic acid sequence if the protein binds to the first nucleic acid sequence and so influences transcription of the second, separate nucleic acid sequence. Generally, “operably linked” means that the DNA sequences being linked are contiguous, although they need not be, and that a gene and a regulatory sequence or sequences (e.g., a promoter) are connected in such a way as to permit gene expression when the appropriate molecules (e.g., transcriptional activator proteins—transcription factors—or proteins which include transcriptional activator domains) are bound to the regulatory sequence or sequences. [0039] By “protein” is meant a sequence of amino acids of any length, constituting all or a part of a naturally-occurring polypeptide or peptide, or constituting a non-naturally occurring polypeptide or peptide (e.g., a randomly generated peptide sequence or one of an intentionally designed collection of peptide sequences). [0040] By “expression” or “gene expression” is meant transcription (e.g., from a gene) and, in some cases, translation of a gene into a protein, or “gene product.” In the process of expression, a DNA chain coding for the sequence of gene product is first transcribed to a complementary RNA, which is often a messenger RNA, and, in some cases, the transcribed messenger RNA is then translated into the gene product—a protein. The terms are also used to mean the degree to which a gene is active in a cell or tissue, measured by the amount of mRNA in the tissue and/or the amount of protein expressed. [0041] As used herein, the terms “vector” or “plasmid” or “plasmid vector” are used in reference to extra-chromosomal nucleic acid molecules capable of replication in a cell and to which an insert sequence can be operatively linked so as to bring about replication of the insert sequence. Vectors are used to transport DNA sequences into a cell, and some vectors may have properties tailored to produce protein expression in a cell, while others may not. A vector may include expression signals such as a promoter and/or a terminator, a selectable marker such as a gene conferring resistance to an antibiotic, and one or more restriction sites into which insert sequences can be cloned. Vectors can have other unique features (such as the size of DNA insert they can accommodate). A plasmid or plasmid vector is an autonomously replicating, extrachromosomal, circular DNA molecule (usually double-stranded) found mostly in bacterial and protozoan cells. Plasmids are distinct from the bacterial genome, although they can be incorporated into a genome, and are often used as vectors in recombinant DNA technology. [0042] The term “expression vector” as used herein refers to a recombinant DNA molecule containing a desired coding sequence and appropriate nucleic acid sequences necessary for expression of the operably linked coding sequence (e.g., an insert sequence that codes for a product) in a particular host cell. [0043] The term “epitope tag” or simply “tag” is meant to include, but not be limited to a GST (glutathione-S-transferase) tag, an HA (haemagglutinin) tag, a Myc tag, a FLAG tag, and a 6×His tag. The preceding listing of such epitope tag polypeptides is meant to be illustrative and not limiting, and there is a large and ever-increasing selection of such epitope polypeptides that are substitutable for substitution with those specifically described herein. One skilled in the art is capable of making desired substitutions without undue experimentation. [0044] By “fusion” or “hybrid” protein, DNA molecule, or gene is meant a chimera of at least two covalently bonded polypeptides or DNA molecules. [0045] As used herein, the term “origin of replication,” “origin,” or “ori” refers to a DNA sequence conferring functional replication capabilities in a host cell—it is a particular DNA sequence at which DNA replication is initiated and proceeds bidirectionally or unidirectionally. Examples include, but are not limited to, the SV40 replication origin, which is sufficient to promote DNA replication in animal cells and in vitro. An origin of replication may be a “high copy number” or “low copy number” origin of replication, and may exhibit a narrow or broad host range. There also exist significant differences between eukaryotic and prokaryotic origins of replication. [0046] By “restriction endonuclease” and “restriction enzyme” is meant enzymes (e.g., bacterial enzymes), each of which cut double-stranded DNA at or near a specific nucleotide sequence (a cognate restriction site). Examples include, but are not limited to, KpnI, EcoRV, SfiI, XhoI, SalI, and NotI. [0047] By “restriction” or “digestion” is meant cleavage of DNA by a restriction enzyme at its cognate restriction site. [0048] By “restriction site” is meant a particular DNA sequence recognized by its cognate restriction endonuclease. [0049] As used herein, the term “purified” or “to purify” refers to the removal of contaminants from a sample. For example, but without limitation, a 6×His affinity tag (comprising six consecutive histidine residues) binds with remarkable selectivity and affinity to certain matrices (e.g., a nickel-nitriloacetic acid (Ni-NTA) metal-affinity chromatography matrix). Thus, a protein engineered to bear a 6×His tag may be purified and isolated rapidly and efficiently. [0050] As used herein, the terms “sequencing” or “DNA sequence analysis” refers to the process of determining the linear order of nucleotides bases in a nucleic acid sequence (e.g., insert sequence) or clone. These units are the C, T, A, and G bases. Generally, to sequence a section of DNA, the DNA sequence of a short flanking region, i.e., a primer binding site, must be known beforehand. One method for sequencing is called dideoxy sequencing (or Sanger sequencing). One example for performing dideoxy sequencing uses the following reagents: 1) the DNA that will be used as a template (e.g., insert sequence); 2) a primer that corresponds to a known sequence that flanks the unknown sequence; 3) DNA nucleotides, to synthesize and elongate a new DNA strand; 4) dideoxynucleotides that mimic the G, A, T, and C building blocks to incorporate into DNA, but that prevent chain elongation, thus acting as termination bases for a DNA polymerase (the four different dideoxynucleotides also may be labeled with different fluorescent dyes for automated DNA sequence analysis); and 5) a nucleic acid polymerizing agent (e.g., DNA polymerase or Taq polymerase, both of which are enzymes that catalyze synthesis of a DNA strand from another DNA template strand). When these reagents are mixed, the primer aligns with and binds the template at the primer binding site. The polymerizing agent then initiates DNA elongation by adding the nucleotide building blocks to the 3′ end of the primer. Randomly, a dideoxynucleotide will integrate into a growing chain. When this happens, chain elongation stops and, if the dideoxynucleotide is fluorescently labeled, the label will be also be attached to the newly generated DNA strand. Multiple strands are generated from each template, each strand terminating at a different base of the template. Thus, a population is produced with strands of different sizes and different fluorescent labels, depending on the terminal dideoxynucleotide incorporated as the final base. This entire mix may, for example, be loaded onto a DNA sequencing instrument that separates DNA strands based on size and simultaneously uses a laser to detect the fluorescent label on each strand, beginning with the shortest. The sequence of the fluorescent labels, read from the shortest fragment to the longest, corresponds to the sequence of the template. The reading may be done automatically, and the sequence may be captured and analyzed using appropriate software. The term “shotgun cloning” refers to the multi-step process of randomly fragmenting target DNA into smaller pieces and cloning them en masse into plasmid vectors. [0051] As used herein, the terms “to clone,” “cloned,” or “cloning” when used in reference to an insert sequence and vector, mean ligation of the insert sequence into a vector capable of replicating in a host cell. The terms “to clone,” “cloned,” or “cloning” when used in reference to an insert sequence, a vector, and a host cell, refer generally to making copies of a given insert sequence. In this regard, to clone a piece of DNA (e.g., insert sequence), one would insert it into a vector (e.g., ligate it into a plasmid, creating a vector-insert construct) which may then be put into a host (usually a bacterium) so that the plasmid and insert replicate with the host. An individual bacterium is grown until visible as a single colony on nutrient media. The colony is picked and grown in liquid culture, and the plasmid containing the “cloned” DNA (the sequences inserted into the vector) is re-isolated from the bacteria, at which point there may be many millions of copies of the vector-insert construct. The term “clone” can also refer either to a bacterium carrying a cloned DNA, or to the cloned DNA itself. [0052] The term “electrophoresis” refers to the use of electrical fields to separate charged biomolecules such as DNA, RNA, and proteins. DNA and RNA carry a net negative charge because of the numerous phosphate groups in their structure. Proteins carry a charge that changes with pH, but becomes negative in the presence of certain chemical detergents. In the process of “gel electrophoresis,” biomolecules are put into wells of a solid matrix typically made of an inert porous substance such as agarose. When this gel is placed into a bath and an electrical charge applied across the gel, the biomolecules migrate and separate according to size, in proportion to the amount of charge they carry. The biomolecules can be stained for viewing (e.g., with ethidium bromide or with Coomassie dye) and isolated and purified from the gels for further analysis. Electrophoresis can be used to isolate pure biomolecules from a mixture, or to analyze biomolecules (such as for DNA sequencing). [0053] As used herein, the terms “PCR” and “amplifying” refer to the polymerase chain reaction method of enzymatically “amplifying” or copying a region of DNA. This exponential amplification procedure is based on repeated cycles of denaturation, oligonucleotide primer annealing, and primer extension by a DNA polymerizing agent such as a thermostable DNA polymerase (e.g., the Taq or Tfl DNA polymerase enzymes isolated from Thermus aquaticus or Thermus flavus , respectively. [0054] As used herein, the term “RT-PCR” refers to reverse transcription polymerase chain reaction, which is used to amplify a particular segment of RNA. Using RT-PCR techniques, the RNA segment is first reverse transcribed into its DNA complement, and then the DNA complement is amplified using PCR. [0055] As used herein, the term “oligonucleotide,” refers to a short length of single-stranded polynucleotide chain. Oligonucleotides are typically less than 100 residues long (e.g., between 15 and 50), however, as used herein, the term is also intended to encompass longer polynucleotide chains. Oligonucleotides are often referred to by their length. For example a 24 residue oligonucleotide is referred to as a “24-mer”. Oligonucleotides can form secondary and tertiary structures by self-hybridizing or by hybridizing to other polynucleotides. Such structures can include, but are not limited to, duplexes, hairpins, cruciforms, bends, and triplexes. Oligonucleotides may be useful as PCR primers. [0056] As used herein, the term “primer” refers to an oligonucleotide, whether occurring naturally as in a purified restriction digest or produced synthetically, which is capable of acting as a point of initiation of nucleic acid synthesis when placed under conditions in which synthesis of a primer extension product which is complementary to a nucleic acid strand is induced, (i.e., in the presence of nucleotides and an inducing agent such as DNA polymerase and at a suitable temperature and pH. The primer is preferably single stranded for maximum efficiency in amplification, but may alternatively be double stranded. If double stranded, the primer is first treated to separate its strands before being used to prepare extension products. Preferably, the primer is an oligodeoxyribonucleotide. The primer must be sufficiently long to prime the synthesis of extension products in the presence of the inducing agent. The exact lengths of the primers will depend on many factors, including temperature, source of primer, and the use of the method. [0057] As used herein, the terms “PCR product,” “PCR fragment,” and “amplification product” refer to the resultant mixture of compounds after two or more cycles of the PCR steps of denaturation, annealing, and extension are complete. These terms encompass the case where there has been amplification of one or more segments of one or more target sequences. [0058] The following examples are offered by way of illustration and not by way of limitation. [0059] Based on available scientific knowledge for in vitro and in vivo biological activities of PSAP, Saposin C or active peptides derived from PSAP, the availability of recombinant human (“rh”) Saposin C and rh-PSAP would allow them to be used in the following disciplines: a) pain control and management; b) nerve regeneration following nerve-damage; c) myelin degenerative diseases; d) diabetic neuropathy, e) research in cell biology in general or, specifically, in vitro and in vivo cancer research; and f) reduce the loss of muscle mass following injury to the muscle's nerve supply. [0060] Despite an increasing interest in PSAP and Saposin C in basic science research and its potential therapeutic applications in clinical medicine, there are only three reports of rh-Saposin C or rh-PSAP proteins: 1) rh-Saposin C expressed by infecting insect cells ( Spodoptera Frugiperda Sf21) with a baculovirus harbouring human Saposin C cDNA (see, e.g., Gopalakrishnan M M, Grosch H W, Locatelli-Hoops S, Werth N, Smolenová E, Nettersheim M, Sandhoff K, Hasilik A. Purified recombinant human prosaposin forms oligomers that bind procathepsin D and affect its autoactivation. Biochem J. 383(Pt. 3), 507-515, 2004; PubMed ID: 15255780. Schultz-Heienbrok R, Remmel N, Klingenstein R, Rossocha M, Sandhoff K, Saenger W, and Maier T. Crystallization and preliminary characterization of three different crystal forms of human saposin C heterologously expressed in Pichia pastoris , Acta Crystallograph Sect F Struct Biol Cryst Commun. 62, 117-120, 2006; PubMed ID: 16511279.); 2) GST-tagged rh-PSAP (81.88 kDa) expressed in wheat germ cell-free protein synthesis system (Abnova, GmbH, Heidelberg, Germany, Cat# H00005660-P01), but the production level with this method is very low for molecules less than 80 kDa (www.abnova.com); and 3) rh-PSAP expressed in E. coli , a prokaryotic system (United States Biological, Inc., Swampscott, Mass., Cat# P9052-90; www.usbio.net). [0061] The following points demonstrate the significance of the availability of our novel constructs and stable transfectants for mass production of rh-PSAP and rh-Saposin C. [0062] pSecTag2A vectors subcloned with rh-PSAP or rh-Saposin C allows a convenient method of overexpressing the two proteins. [0063] Human Saposin C is not (naturally an extracellular secreted molecule. By subcloning the full length human Saposin C DNA sequence into pSecTag2A vector, now it is possible to have extracellular secretion of the protein. [0064] Moreover, expressing these proteins in a mammalian cell system (e.g., CHO-K1), as in the present invention, yields proteins that are appropriately glycosylated—unlike previously—isolated PSAP and Saposin C proteins expressed in non-mammalian cells (e.g., Sf9 insect cells or E. coli ). The cells of nonhuman species do not glycosylate their proteins in the same way as human cells do. This is important because glycosylation profoundly affects biological activity, function, clearance from circulation, and (crucially) antigenicity. [0065] Recombinant human Saposin C has never been produced for commercial purposes. The only available report of rh-Saposin C has the following characteristics: a) it is made only in an academic institution abroad (University of Bonn, Germany) and only for research purposes; b) it is made in insect cells (low expression level, non-mammalian eukaryotic cells) infected with a baculovirus containing 6×His-tagged human Saposin C cDNA; and c) it is non-glycosylated, or its glycosylation is not analogous to that of native Saposin C This lack of posttranslational modification might potentially limit some of the resulting protein's biological activities. [0066] The other two rh-PSAP proteins (Commercially available from Abnova, Heidelberg, DE and from United States Biological, Inc., Massachusetts) are expressed in non-eukaryotic cells and so do not bear native mammalian posttranslational modifications—such as glycosylation—that may be important for their biological activities in mammalian cells. Naturally-expressed PSAP and Saposin C isolated from mammalian cells are heavily glycosylated. Finally, according to the manufacturers' data sheet, the biological activities of these rh-PSAP proteins are unknown. [0067] Both rh-PSAP and rh-Saposin C constructs described in this invention report are fully characterized and demonstrate biological activities in human cell lines. These constructs could be independently available and could be used for transfection into any type of benign or malignant human cells for further basic science research or therapeutic applications. [0068] In addition to the pSeqtag2A-rh-PSAP and pSecTag2A-rh-Saposin C constructs described here, we have also established and characterized stable-transfectants of CHO-K1 cells with the following characteristics: a) CHO-K1 stable transfectants express rh-PSAP or rh-Saposin C; b) these cells are immortal and could be propagated in available culture medium (with minimal growth requirements) and conveniently in small-scale in a laboratory or large-scale (industrial); c) both rh-PSAP and rh-Saposin C are tagged with hexa-histidine (6×His) sequence. [0069] The 6×His sequence provides a convenient method for high quality purification and can also be used to trace the recombinant proteins after their use in in vivo (e.g., after injection into laboratory animals and following their tissue distribution or localization by immunohistochemical staining with anti-histidine antibody) or in vitro studies (e.g., after addition to cell culture, its localization on the cell membrane or involvement with intracellular trafficking could be investigated by different methods such as immunofluoresence staining). Based on these characteristics, we have used and we herein present a methodology that provides a reliable and convenient method for purification of final proteins expressed by the cells. [0070] The applications for the pSecTag2A-rh-PSAP and pSecTag2A-rh-Saposin C constructs and stable CHO-K1-transfectants stably expressing soluble rh-PSAP and rh-Saposin C are for basic science research and clinical therapy in the field of cancer, neuropathies (e.g., diabetic neuropathies), pain control and management, nerve regeneration (after damage to nervous system), diseases related to muscles (following hypoxia or injury to muscles or their nerve supply), myelin degenerative disorders (e.g., multiple sclerosis), neuroembryological diseases, neuronal differentiation, neurochemistry, and neurobiology. [0071] Here, for the first time we report a continuous source, high-level, and stable expression of recombinant human Saposin C and PSAP with a C-terminal hexa-histidine (6×His) tag in Chinese hamster ovary (CHO-K1) cells that are recognized as the most popular mammalian host for commercial production of proteins. 6×His-tagged rh-Saposin C and 6×His-tagged rh-PSAP were purified from the culture medium of stably transfected CHO cells using an anti-His affinity gel. In addition, we demonstrate the biological activities of these proteins functional assays (cell proliferation and motility), using human prostate stromal cells and cancer cells. [0072] The differences between rh-PSAP and rh-Saposin C described in the prior art is summarized in TABLE 1 below. [0000] TABLE 1 Characteristics of rh-PSAP and rh-Saposin C from different systems Protein Expression M.W. (reference) 6 × His System Glycosylation (kDa) rh-PSAP Yes CHO-K1 Yes; high level 68-72 (SEQ ID NO: 17) rh-PSAP (1) No Baculovirus- Yes; low level 58 infected Sf9 rh-PSAP (2) No E. coli No 81.88 rh-PSAP (3) Yes E. coli No Unknown rh-Saposin C Yes CHO-K1 Yes 10 (SEQ ID NO: 18) rh-Saposin C (4) Yes E. coli No 8 rh-Saposin C (5) Yes Baculovirus- Yes; low level 8 infected Sf9 [0073] In TABLE 1, the rh-PSAP from reference (1) is described in Hiraiwa M, O'Brien J S, Kishimoto Y, Galdzicka M, Fluharty A L, Ginns E I, Martin B M. Isolation, characterization, and proteolysis of human prosaposin, the precursor of saposins (sphingolipid activator proteins). Arch Biochem Biophys. 304, 110-116, 1993; the rh-PSAP from reference (2) is commercially available from Abnova Co., Taiwan, Cat No. H00005660-P01, and which also bears a GST tag; and the rh-PSAP from reference (3) is commercially available from United States Biological, Inc., Swampscott, Mass., Cat# P9052-90; www.usbio.net. [0074] In TABLE 1, the rh-Saposin C from reference (4) is described in Qi X, Leonova T, Grabowski G A. Functional human saposins expressed in Escherichia coli . Evidence for binding and activation properties of saposins C with acid beta-glucosidase. J Biol Chem. 269, 16746-16753, 1994; and the rh-Saposin C from reference (5) is described by Sandhoff K., Unpublished data, From the Institut für Organische Chemie und Biochemie, Universität Bonn, D-53121 Bonn, Germany. Example 1 Cell Lines and Cell Culture [0075] Human prostate stromal cells (Pr.St; Catalogue No. CO-2608) were purchased from BioWhittaker (Walkersville, Md.). The cells were maintained according to the manufacturer's instructions in a defined culture medium specific for each cell type, named “Pr.EGM” (Catalogue No. CC3166) and “SCGM” (Catalogue No. CC-3205) for prostate epithelial and stromal cell lines, respectively. A human prostate cancer cell line, PC-3 was purchased from the ATCC (Cat # CRL-1435) and cultured routinely in Dulbeccos's Modified Eagle's Medium (DMEM) supplemented with 10% heat-inactivated fetal bovine serum (HI-FBS). Chinese hamster ovary cell line (CHO-K1: ATCC, Manassas, Va., USA, Cat No. CCL-61) and 293T/17/17 human embryonic kidney cell lines (ATCC, Cat # CRL-11268) were purchased from ATCC. CHO-K1 cells were routinely cultured in Kaighn's modification of Ham's F12 medium (F12K) supplemented with 2 mM L-glutamine, 1.5 g/L sodium bicarbonate, and 10% FBS. The 293/T17 cell line was maintained in DMEM with 4 mM L-glutamine, 4.5 g/L glucose, 1.5 g/L sodium bicarbonate, and supplemented with 10% FBS. [0076] Baculovirus expressed recombinant human Saposin C (Bac-rh-Saposin q and goat anti-human Saposin C antibody were provided as gifts from Professor K. Sandoff (Bonn, Germany), and were characterized by ELISA, immunoblot, and immunoprecipitation. Purified human milk-PSAP (PSAP purified from human milk) and mouse monoclonal anti-PSAP antibody were gifts from Professor Masao Hiraiwa (University of California, San Diego) and have been characterized previously for Western blotting and other techniques. Example 2 Construction of rh-PSAP and rh-Saposin C Expression Vectors [0077] Prosaposin is the precursor protein of saposins A, B, C, D with 524 amino acids including a 16 amino acids signal peptide (SP) which leads the secretion of mature prosaposin into culture supernatant. However heterogeneous signal peptides, such as Ig kappa-chain signal peptide, have been shown more efficient for secreted expression of recombinant proteins in mammalian cells. See, e.g., Coloma M J, Hastings A, Wims L A, Morrison S L. Novel vectors for the expression of antibody molecules using variable regions generated by polymerase chain reaction. J Immunol Methods. 52, 89-104, 1992; PubMed ID: 1640112. We first tested if the secreted expression level of rh-PSAP in the pSecTag2A vector (Invitrogen, Carlsbad, Calif., USA, Cat No. V900-20) with the murine Ig kappa-chain signal peptide will be higher than in the pcDNA3.1 vector (Invitrogen, Carlsbad, Calif., USA, Cat No. V790-20) having the prosaposin native signal peptide. In addition, we tested whether adding prosaposin native signal peptide after the Ig kappa signal peptide in pSecTag2A vector would increase the secretion efficiency of recombinant prosaposin. As shown in FIG. 1 , proteins expressed from pSecTag2 vectors are fused at the N-terminus to the murine Ig kappa-chain leader sequence for protein secretion and at the C-terminus to a peptide containing six tandem histidine residues for detection and purification. The Zeocin™ resistance gene of the pSecTag2 vectors ( FIG. 1 ) permits selection in both E. coli and mammalian cells in the presence of the antibiotic Zeocin™ (a formulation of phleomycin D1, a copper-chelated glycopeptide antibiotic produced by Streptomyces CL 990, available from InvivoGen, San Diego, Calif.). The pSecTag2 vector exists as versions A, B, and C, to facilitate correct in-frame fusion with the Ig kappa-chain leader sequence. [0078] To construct rh-PSAP and rh-Saposin C expression vectors, total RNA was extracted from normal human prostate epithelial (Pr.EP) cells (Biowhittaker, Walkersville, Md., USA) with RNeasy Mini Kit (Qiagen, Maryland, USA, Cat No. 74014). The full-length PSAP cDNA was synthesized by RT-PCR with Affinity Script Multi Temperature cDNA Synthesis Kit (Stratagene, TX, USA, Cat No. 200436). Specific primers were designed to introduce a hexa-histidine (6×His) tag to the c-terminus of PSAP or Saposin C to facilitate recombinant protein purification, which are listed in TABLES 2 and 3, below. All primers were synthesized by Integrated DNA Technology (IDT, Inc: Coralville, Iowa). [0000] TABLE 2 Primers for rh-PSAP and rh-Saposin C expression vectors Vector Name Length Primer Sequence pcDNA3.1 PSAP-1F 32 5′-CGGGGTACCACCATGTACGCCCT (rh-PSAP-His6) Forward CTTCCTCCT-3′ (SEQ ID NO: 10) PSAP-1B 63 5′-TATGATATCCTAATGGTGATGGTG Backward ATGGTGGTTCCACACATGGCGTTTG (6 × His tagged) CAATGCTCGACAGC-3′ (SEQ ID NO: 11) pSecTag2A PSAP-2F 36 5′-AAAGCGGCCCAGCCGGCCGGCCC (rh-PSAP-His6 Forward GGTCCTTGGACTG-3′ or (SEQ ID NO: 12) rh-PSAP-SP-His6) PSAP-SP-2F 37 5′-AAAGCGGCCCAGCCGGCCATGTA Forward CGCCCTCTTCCTCC-3′ (SEQ ID NO: 13) PSAP-2B 50 5′-CCGCTCGAGCTAGTGATGGTGATGG Backward TGATGGTTCCACACATGGCGTTTGC-3′ (SEQ ID NO: 14) pSecTag2A Saposin C-F 39 5′-AAAGCGGCCCAGCCGGCCTCTGAT (rh-Saposin C-His6) Forward GTTTACTGTGAGGTG-3′ (SEQ ID NO: 15) Saposin C-B 49 5′-CCGCTCGAGCTAGTGATGGTGATG Backward GTGATGCGTGCCAGAGCAGAGGTGC-3′ (SEQ ID NO: 16) [0079] To construct pcDNA3.1-rh-PSAP-His6 vector (1-524aa, with native signal peptide), the gene for rh-PSAP was amplified by PCR using the above cDNA template and sub-cloned into KpnI and EcoRV sites of the pcDNA3.1 vector. To construct pSecTag2A-rh-PSAP-His6 (17-524aa, without native signal peptide), pSecTag2A/rh-PSAP-SP-His6 (1-524aa, with native signal peptide (SP)), or pSecTag2A-rh-Saposin C-His6 (311-391aa, without native signal peptide) vectors (SEQ ID NO:8 & SEQ ID NO:9, respectively), the gene for rh-PSAP or rh-Saposin C was amplified by PCR using the above cDNA template (from the pcDNA3.1-rh-PSAP-His6 vector) with Phusion High-Fidelity DNA Polymerase (New England Biolabs, Beverly, Mass., USA, Cat No. F530S) and specific primers with sequences compatible for digestion with restriction enzymes (SfiI+XhoI) and subcloning into pSecTag2A vector (TABLES 2 & 3). [0000] TABLE 3 Summary of rh-PSAP and rh-Saposin C expression vectors PSAP PSAP native Ig-kappa Vector Gene Forward Backward signal Signal 6xHis Name (aa) Primer Primer peptide peptide Tag Cloning Sites pcDNA3.1- 1-524aa PSAP-1F PSAP-1B Yes No Yes KpnI + EcoRV rh-PSAP- His6 pSecTag2A- 17-524aa PSAP-2F PSAP-2B No Yes Yes SfiI + XboI rh-PSAP- His6 pSecTag2A- 1-524aa PSAP- PSAP-2B Yes Yes Yes SfiI + XboI rh-PSAP- SP-2F SP-His6 pSecTag2A- 311-391aa SAPC-F SAPC-B No Yes Yes SfiI + XboI rh-Saposin C-His6 [0080] The PCR products were gel-purified by DNA Gel Extraction Kit (Qiagen, Maryland, USA, Cat No. 28704) and digested with SfiI (New England Biolabs, MA, USA, Cat No. R0123S) and XhoI (New England Biolabs, Beverly, Mass., USA, Cat No. R0146S), yielding rh-PSAP insert and rh-Saposin C insert. The inserts were ligated by T4 DNA ligase (Invitrogen, Carlsbad, Calif., USA, Cat No. 15224) into pSecTag2A vector which was digested with the same enzymes, and transformed into One Shot E. coli Top10 Competent cells (Invitrogen, Carlsbad, Calif., USA, Cat No. C7510-03). To construct vector, all plasmids were purified by Qiaprep Spin Miniprep Kit (Qiagen, Maryland, USA, Cat No. 27106). The above three vectors harboring rh-PSAP (SEQ ID NO:6) and rh-Saposin C (SEQ ID NO:7) cDNA were subjected to DNA sequencing in both directions (5′ to 3′ and 3′ to 5′) and proved to be 100% accurate and equal to native PSAP and Saposin C sequence (ACGT Inc, Wheeling, Ill., USA). Example 3 Transient Transfection and Expression of rh-PSAP in 293T/17 Cells [0081] To select the best vector for rh-PSAP expression, we first expressed rh-PSAP in Human Embryonic Kidney (HEK) 293T/17 cells by transient transfection. 293T/17 cell line has been engineered to constitutively express the temperature sensitive gene for simian virus 40 (SV40) T-antigen, allowing for episomal replication of the plasmids which contain the SV40 origin of replication sequence and highly transient expression of recombinant proteins. [0082] 293T/17 cell line (ATCC, Manassas, Va., USA, Cat No. CRL-11268) was cultured in Dulbecco's Modified Eagle Medium (DMEM, Gibco, Grand Island, N.Y., USA, Cat No. 11595) supplemented with 10% Heat Inactivated Fetal Bovine Serum (HI-FBS, Gibco, Auckland, NZ, USA, Cat No. 10082) and 1% penicillin/streptomycin (P/S) antibiotics (Sigma, St. Louis, Mo., USA, Cat No. A5955) in a humidified 5% CO2 incubator at 37° C. 5×10 5 cells were seeded in 60 mm dishes and cultured overnight to 40%-60% confluency. 2 μg DNA was mixed with 10 μl Lipofectin reagent (Invitrogen, Carlsbad, Calif., USA, Cat No. 18292-037) in Opti-MEM Reduced Serum Medium (“Opti-MEM,” Gibco, Auckland, NZ, USA, Cat No. 31985) for 16 hour transfection. The cells were replaced with 2 ml fresh Opti-MEM reduced serum medium and cultured for additional 48 hours. [0083] The culture supernatants (2.5 ml) were centrifuged at 1500 rpm for 5 minutes to remove cellular debris and concentrated 10-fold to final 250 μl with 2 ml Vivaspin Centrifuge Tube with 10 kDa cut-off membrane (Vivascience, Stonehouse, UK, Cat No. VS0602). Total protein concentration in supernatant was measured by the BCA Protein Assay Kit (Pierce, Rockford, Ill., USA, Cat No. 23225). A total of 10 μg protein supernatant for each transfection were separated in 4-20% Novex Tris-Glycine Polyacrylamide Gel (Invitrogen, Carlsbad, Calif., USA, Cat No. EC6028BOX), and then electrotransferred to Hybond PVDF membrane (Amersham, Little Chalfont, UK, Cat No. RPN303F). The membranes were blocked with 5% BSA (Santa Cruz, Calif., USA, Cat No. SC-2323) in TBST buffer (20 mM Tris HCl, 150 mM NaCl, 0.1% Tween 20) for 1 hour at room temperature. The membranes were first incubated with mouse anti-PSAP antibody as the primary antibody (1:500 dilution in 0.2% BSA in TBST) and then incubated with goat anti-mouse IgG-horseradish peroxidase-conjugated secondary antibody (1:2000 dilution in 0.2% BSA in TBST, Santa Cruz, Calif., USA, Cat No. SC-2005) each for 1 hour at room temperature. The blots were then detected by ECL Plus reagents (Amsersham, Little Chalfont, UK, Cat No. RPN2109). [0084] As shown in FIG. 2 , 293T/17 cells transiently transfected with the pSecTag2A-rh-PSAP-His6 vector (with murine Ig-kappa signal peptide, FIG. 2 lane 2) demonstrated a higher level of PSAP protein expression (secretion) in culture supernatant than 293T/17 cells transiently transfected with the pcDNA3.1-rh-PSAP-His6 (with native signal peptide, FIG. 2 , lane 1) or pSecTag-2A-rh-PSAP-SP-His6 vector (with both native signal peptide and murine Ig-kappa signal peptide, FIG. 2 , lane 3). This data suggested that the murine Ig-kappa signal peptide sequence is more efficient in leading the secretion of recombinant PSAP than its native signal peptide or a combination of both signal peptides. As a control, 293T/17 cells transfected with empty vectors (pcDNA3.1 or pSecTag2A, FIG. 2 , lanes 4 and 5, respectively) secreted very low levels of endogenous human prosaposin. However, transient transfection of 293T/17 cells with pSecTag/2A-rh-Saposin C-His6 tag did not reveal a detectable rh-Saposin C expression in the culture supernatant (data not shown). Example 4 CHO-K1 Transfection and Selection of Stable Cell Lines [0085] Although the 293T/17 cell line proved a useful model cell line for rh-PSAP expression with either pcDNA3.1 or pSecTag2A vectors harboring PSAP-cDNA, this cell line was only good and feasible for transient expression of small quantities of recombinant proteins. In addition, using transient transfection in this cell line did not lead to a detectable rh-Saposin C protein in concentrated culture supernatant. In order to bypass these technical limitations and to achieve a reliable method for consistent production of large quantities of pure rh-PSAP and rh-Saposin C proteins for biological and potential clinical therapeutic usage, we chose the CHO-K1 cell line (see, e.g., American Type Culture Collection No. CCL-61). This cell line is one of the most popular mammalian hosts for stable expression of recombinant proteins especially for clinical and therapeutic applications. See, e.g., Andersen D C, Krummen L. Recombinant protein expression for therapeutic applications. Curr Opin Biotechnol. 13, 117-123, 2002; PubMed ID: 11950561. Warnock J N, Al-Rubeai M. Bioreactor systems for the production of biopharmaceuticals from animal cells. Biotechnol Appl Biochem. 45(Pt 1), 1-12, 2006; PubMed ID: 16764553. So far there is no report about the expression of rh-PSAP and rh-Saposin C in CHO-K1 cell line. We used the vector pSecTag2A/rh-PSAP-His6 for the transfection of CHO-K1 cells and selection of stable cell lines. [0086] For transfection, 3×10 5 cells were seeded in 60 mm dishes and cultured overnight to 20-30% confluency. 4 μg DNA of pSecTag2A/rh-PSAP-His6 or pSecTag2A/rh-Saposin C-His6 vector was mixed with 20 μl Lipofectin reagent in Opti-MEM reduced serum medium for 16 hours transfection. The cells were changed to Ham's F-12K medium (Mediatech, through Fisher Scientific) supplemented with 10% FBS and 1% Penicillin/Streptomycin, and cultured for an additional 48 hours to reach near confluency. [0087] The cells in 60 mm dishes were collected by 0.25% Trypsin-EDTA (Gibco, Grand Island, N.Y., USA, Cat No. 25200). 20% of the cells were diluted to ten 100 mm dishes in F-12K selective medium supplemented with 10% HI-FBS, 1% Penicillin/Streptomycin and 500 μg/ml Zeocin (Invitrogen, Carlsbad, Calif., USA, Cat No. 45-0430). At the fourth day, the cells were changed to the same fresh selective medium. At the seventh day, a single colony was isolated with cloning cylinders (Sigma, St. Louis, Mo., USA, Cat No. C3983) and expanded in 24-well plates and then in T25 flasks in the same selective medium. It took about another 7-10 days for the cells in T25 flasks to reach greater than 90% confluency. The cells were then collected and split into one T75 flask (to make cell stock) and another T25 flask (to measure the relative productivity rh-PSAP and rh-Saposin C by Western blotting). For cell stock, after the cells in T75 flask were 90% confluency, the cells were collected by trypsin, re-suspended in F-12K medium supplemented with 20% HI-FBS, 1% Penicillin/Streptomycin and 10% DMSO (Sigma, St. Louis, Mo., USA. Cat No. D2650) in several tubes, and then stored in liquid nitrogen. [0088] After the cells in the new T25 flask reached 90% confluency, they were washed twice with phosphate-buffered saline (PBS) and replaced with 2 ml Opti-MEM reduced serum medium supplemented with 1% penicillin/streptomycin. After culture for 24 hours, the supernatants were collected and 10 μg supernatant protein for each clone was subjected to SDS-PAGE and Western blotting as in Example 3 and FIG. 2 . Goat anti-Saposin C polyclonal antibody (1:100 dilution in 0.2% BSA in TBST) was used as primary antibody. This antibody can detect both human Saposin C and PSAP. Donkey anti-goat IgG-horseradish peroxidase-conjugated antibody (1:2000 dilution in 0.2% BSA in TBST, Santa Cruz, Calif., USA, Cat No. SC-2020) was used as secondary antibody. [0089] The expression results are shown in FIG. 3 . We obtained three rh-PSAP highly expressive stable CHO-K1 clones, which are named as Clone 2-2, Clone 2-12, and Clone 2-14 from a total of fifteen Zeocin-resistant pSecTag2A/rh-PSAP-His6 clones. We also obtained three rh-Saposin C highly expressive stable CHO-K1 clones, which are named as Clone 3-2, Clone 3-8, and Clone 3-13 from a total of fourteen Zeocin-resistant pSecTag2A/rh-Saposin C-His 6 clones. Among them, Clone 2-2 and Clone 3-13 were finally used for large-scale expression and purification of rh-PSAP (SEQ ID NO:17) and rh-Saposin C (SEQ ID NO:18), respectively. Example 5 Large-Scale Expression and Purification of rh-PSAP and rh-Saposin C [0090] For a typical large-scale expression and purification, two tubes of Clone 3-13 or Clone 2-2 cell stock were recovered from liquid nitrogen and amplified in T150 flasks in 30 ml of F-12K medium supplemented with 10% FBS, 1% Penicillin/Streptomycin and 250 μg/ml Zeocin to near confluency (about three days). The cells were then split into eight T150 flasks and cultured to near confluency (about three days). The cells were then split into seventeen T500 Triple Flasks (Nunc, Roskilde, Denmark, Cat No. 132920) containing 60 ml of F-12K medium supplemented with 10% FBS, 1% Penicillin/Streptomycin and 250 μg/ml Zeocin. After reaching 90% confluency, the cells were washed twice with PBS and replaced with 60 ml Opti-MEM reduced serum medium supplemented with 1% Penicillin/Streptomycin. After 48 hours, the culture supernatant (about 1 liter) was collected in two 500 ml conical centrifuge bottles (Corning, N.Y., USA, Cat No. 431123) by centrifugation at 1500 rpm for 5 minutes at 4° C. to remove cellular debris. The cleared supernatant was stored at −80° C. for further purification. [0091] Recombinant human PSAP and Saposin C were purified by a batch-absorption method using Ni-NTA Superflow Resins (Qiagen, Maryland, USA, Cat No. 1018611). One liter supernatant was mixed with 100 ml neutralization buffer (0.5 M NaPi, pH 8.0, 1.5 M NaCl, 2 mM imidazole), centrifuged at 15,000×g for 10 minutes at 4° C., filtered through 0.22 μm membrane (Corning, N.Y., USA, Cat No. 430758), and pooled in two 500 ml conical centrifuge bottles. The pooled filtered supernatant was incubated with 5 ml Ni-NTA resin overnight at 4° C. or for 4 hours at room temperature by slow gyroscopic spin at 100 rpm. The resin was subsequently collected and loaded onto an empty 5 ml polypropylene purification column (Qiagen, Maryland, USA, Cat No. 34964). To remove non-specifically bound proteins, the resin was first washed four times with 5 ml of binding buffer (50 mM Na 2 HPO 4 , pH 8.0, 300 mM NaCl) containing 10 mM imidazole (Sigma, St. Louis, Mo., USA, Cat No. 11102-1000) and then washed four times with 5 ml of binding buffer containing 20 mM imidazole. The Ni-NTA resin-bound rh-PSAP or rh-Saposin C were eluted four times with 2.5 ml of binding buffer containing 50 mM imidazole and then four times with 2.5 ml of binding buffer containing 100 mM imidazole. For each washing and elution, the 2.5 ml fraction was collected into one tube. [0092] The appropriate fractions (about 10-15 ml) containing the purified recombinant protein were pooled, and buffer-exchanged twice to PBS via ultrafiltration with Vivaspin centrifugal concentrators (Sartorius Stedim Biotech S.A., France). For rh-PSAP, 6 ml Vivaspin concentrator with 10 kDa cut-off membrane (Vivascience, Stonehouse, UK, Cat No. VS0602) was used for buffer exchange and condensation. For rh-Saposin C with an approximate molecular weight of 10 kDa a 6 ml centrifuge tube with 50 kDa cut-off membrane (Vivascience, Stonehouse, UK, Cat No. VS0631) was first used to remove non-specific proteins of high molecular weight by collecting the flow-through, and then 15 ml centrifuge tube with 2 kDa cut-off membrane (Vivascience, Stonehouse, UK, Cat No. VS15RH91) was used for buffer exchange and condensation. After two rounds of buffer exchange, the final imidazole concentration was less than 3 mM. The purified proteins were quantified by measuring the absorbance at OD 280 nm using serial dilutions of BSA as standards. The purified rh-PSAP and rh-Saposin C were filtered through 0.22 μm filters and stored at −80° C. for future use without detectable loss of biological activities. Several methods were used to characterize the purified rh-PSAP and rh-Saposin C, including SDS-PAGE with Coomassie Blue R-250 Staining (Bio-Rad, Hercules, Calif., Cat No. 161-0436), Silver Staining Plus (Bio-Rad, Hercules, Calif., Cat No. 161-0449), and Western blotting with mouse anti-PSAP antibody or goat anti-Saposin C polyclonal antibody. [0093] For Coomassie Blue R-250 staining, culture supernatants and imidazole eluted fractions for rh-PSAP and rh-Saposin C were separated in a 4-20% gel. After SDS-PAGE, the gel was incubated with 50 ml Coomassie Blue R-250 Staining Solution (Bio-Rad, Hercules, Calif., Cat No. 161-0436) for 1 hour with gentle shaking at room temperature. Then the gel was incubated with 50 ml de-staining buffer (45% methanol and 10% acetic acid in double-distilled (“dd”) H 2 O). The de-staining buffer was changed several times, until the gel showed clear protein bands and background staining was satisfactorily eliminated. [0094] The Coomassie blue staining results for rh-PSAP and rh-Saposin C purification are shown in FIG. 4 . Most non-specific bound proteins were washed away by 10 mM and 20 mM imidazole washing. Purified rh-PSAP and rh-Saposin C were completely eluted by 50 mM and 100 mM imidazole washing steps. The purified rh-PSAP showed a molecular weight of approximately 72 kDa, which is the same size as native human prosaposin secreted by PC3 prostate cancer cells. The purified rh-Saposin C showed a single band of approximately 10 kDa. For a typical purification from 1 L supernatant, the yield of rh-PSAP was 1.5 to 3 mg/L, and the yield of rh-Saposin C was 0.25 to 0.5 mg/L. [0095] For silver staining, we used the Silver Staining Plus Kit (Bio-Rad, Hercules, Calif., Cat. No. 161-0449). After SDS-PAGE, the gel was fixed with 200 ml fixative enhancer solution (50% methanol, 10% acetic acid, 10% fixative enhancer concentrate, 30% ddH 2 O) for 30 minutes, washed twice with 200 ml ddH 2 O, and then stained with 100 ml staining and developing solution (5 ml silver complex solution, 5 ml reduction moderator solution, 5 ml image development reagent, 50 ml development accelerator solution, 35 ml ddH 2 O) for 10-15 minutes until the gel showed clear protein bands. The reaction was stopped with 100 ml of 5% acetic acid for 10 minutes. [0096] The silver staining results for rh-PSAP and rh-Saposin C are shown in FIG. 5 . The purity of rh-PSAP and rh-Saposin C was estimated to be above 95% according to the silver staining results. The purified rh-PSAP showed two additional bands at approximately 35 and 55 kDa. These bands represent proteolytically-cleaved products of extracellular PSAP in the form of various tri-saposins or di-saposins. This type of intracellular or extracellular fragmentation of PSAP is a common observation and has been reported in native protein isolated from human seminal plasma and breast milk or rh-PSAP expressed in baculovirus-infected insect cells and their culture medium, as well as in incubations of purified PSAP with cathepsin D enzyme. See, e.g., Hiraiwa M, O'Brien J S, Kishimoto Y, Galdzicka M, Fluharty A L, Ginns E I, Martin B M. Isolation, characterization, and proteolysis of human prosaposin, the precursor of saposins (sphingolipid activator proteins). Arch Biochem Biophys. 304, 110-116, 1993; PubMed ID: 8323276. Kondoh K, Hineno T, Sano A, Kakimoto Y. Isolation and characterization of prosaposin from human milk Biochem Biophys Res Commun. 181, 286-292, 1991; PubMed ID: 1958198. Henseler M, Klein A, Glombitza G J, Suzuki K, Sandhoff K. Expression of the three alternative forms of the sphingolipid activator protein precursor in baby hamster kidney cells and functional assays in a cell culture system. J Biol. Chem. 271, 8416-8423, 1996; PubMed ID: 8626540. [0097] Western blotting was done as in EXAMPLE 3 (“Transient transfection and expression of rh-PSAP in 293T/17 cells”). Briefly, purified rh-PSAP and rh-Saposin C were subjected to SDS-PAGE and then transferred to PVDF membrane. After BSA blocking, mouse anti-PSAP and goat anti-Saposin C were used to blot rh-PSAP and rh-Saposin C, respectively. The Western blotting results for rh-PSAP and rh-Saposin C are shown in FIG. 6 . Example 6 Biological Activity of Purified rhPSAP and rhSAPC CHO-K1 Purified Recombinant Human-Saposin C and PSAP Stimulate Prostate Stromal Cell Proliferation [0098] To examine the biological activities of the recombinant proteins expressed and purified here (rh-Saposin C and rh-PSAP), we tested their effect on bromodeoxyuridine (BrdU incorporation into newly synthesized DNA. BrdU can be incorporated into the newly-synthesized DNA of replicating cells, substituting for thymidine during DNA replication. Detection of BrdU in these cells thus indicates that the cells were actively replicating their DNA, and so were actively proliferating. We used a BrdU Cell Proliferation Assay Kit, following the manufacturer's instructions (The Exalpha Biologicals, Inc, Maynard, Mass., Cat# X1327K2). As a positive (active) control, we used rh-Saposin C from the baculovirus expression system in insect cells. PC3 and prostate stromal cells were seeded in 96-well plate at 1000 cells/well in their growth medium. After 3 days, they were incubated either in serum-free basal medium or medium supplemented with either rh-Saposin, or rh-PSAP at concentrations of 0.1, 1.0, 10, or 100 ng/ml. After incubation for 4 days and refreshing the recombinant protein after the first 2 days, BrdU incorporation was determined according to the kit manufacturer's instructions. The results are shown in FIG. 7 , in which each point represents the mean±SEM of 8 replicates from a representative experiment of three independently-repeated experiments. [0099] As we expected, baculovirus expressed rh-Saposin C increased BrdU incorporation into newly synthesized DNA up to 32% in PC3 cells and up to 66% in PrSt cells ( FIG. 7 ). In a dose dependent manner, rh-Saposin C stimulated BrdU incorporation into newly synthesized DNA by 19-33% in PC3 cells and by 43-61% in PrSt cells. Finally, rhPSAP increased BrdU incorporation by 7-32% in PC3 cells and by 30-60% in PrSt cells. Example 7 Biological Activity of Purified rhPSAP and rhSAPC CHO-K1 Purified rh-Saposin C and rh-PSAP Stimulate Prostate Stromal and Cancer Cell Motility [0100] To test the effect of the pSecTag2A-expressed recombinant proteins rh-Saposin C and rh-PSAP on PC3 and PrSt cell motility, a cell migration assay was performed using 24-well transwell units with 8-μm polycarbonate filters (Costar, Cat # 3422, Becton Dickinson, Bedford, Mass.). For the experiment, the lower compartment of each transwell unit contained 400 μl of basal media supplemented with 2% FBS and 0.1% BSA. Baculovirus-expressed rh-Saposin C (as a positive control), rh-Saposin C, or rh-PSAP were added to the lower compartment at the following concentrations: 0 (control), 0.1 ng/ml, 1 ng/ml, 10 ng/ml, or 100 ng/ml. [0101] Cultured cells were freshly harvested by trypsinization and counted. Approximately 5×10 4 cells for PC3 cell line and 1.5×10 4 cells for PrSt cells were resuspended in 200 μl of serum-free medium with 0.1% BSA, and were placed in the upper compartment of the transwell unit. After 24 hours of incubation at 37° C., cells in both the upper and lower compartments were fixed in methanol and stained with Diff-Quick (Dade, Aguada, Puerto Rico). Non-migratory cells in the upper surface of the filter were removed by wiping with a cotton swab. Cells under the filter were counted. The results are shown in FIG. 8 . Each bar represents the mean±SEM of 8 replicates from a representative experiment of three independently repeated experiments. [0102] PrSt cell migratory response to recombinant proteins was more pronounced than the response seen in PC-3 cells. As expected, baculovirus-expressed rh-Saposin C in a dose-dependent manner increased cell migration in PC-3 cells by 14-64% and in PrSt cells by 3-96%. As seen in FIG. 8 , rh-Saposin C and rh-PSAP increased PrSt cells migration by 19-130% and 8-80%, respectively. In PC-3 cells, rh-Saposin C and rh-PSAP increased cell migration by 25-100% and 20-81%, respectively. These data indicate that both pSecTag2A-expressed/purified rh-Saposin C and rh-PSAP from CHO-K1 clones are capable of eliciting a biological response of cell motility in mammalian cells and are thus properly considered biologically active molecules. [0103] All references cited in this specification are herein incorporated by reference as though each reference was specifically and individually indicated to be incorporated by reference. The citation of any reference is for its disclosure prior to the filing date and should not be construed as an admission that the present invention is not entitled to antedate such reference by virtue of prior invention. [0104] It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above. Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention set forth in the appended claims. The foregoing embodiments are presented by way of example only, the scope of the present invention is to be limited only by the following claims.

The invention relates to the establishment of expression vectors replicable in a mammalian cell, including a DNA sequence encoding human prosaposin (PSAP) or Saposin C, operably linked with regulatory DNA capable of effecting the expression of the PSAP and Saposin C DNA coding sequence in the cells. In addition, the invention relates to mammalian cells (CHO-K1) stably transfected with such expression vectors and methods of producing human Saposin C or PSAP, including transfecting a mammalian cell with expression vectors, maintaining and propagating the cell in culture medium, and isolating soluble rh-Saposin C or rh-PSAP from the medium. Purified rh-Saposin C and rh-PSAP are useful as reagents for studying biological responses and signal transduction mechanism in benign or malignant cells, as standard proteins in diagnosis or screening of benign or malignant diseases, or as medicine for the treatment of diseases or disorders affecting musculoskeletal system or peripheral and central nervous system.

FIELD OF THE INVENTION [0001] This invention relates to hairstyling generally, and is more particularly directed to a device and method that is useful in hair coloring. BACKGROUND OF THE INVENTION [0002] Hair stylists use coloring strips as accessories to color highlighting. Coloring strips are commonly formed of aluminum foil or plastic sheets, although they may be formed from other similar sheet like materials, such as paper. Coloring strips formed from any suitable material may be referred to herein as “foils,” even though the coloring strip is not formed of aluminum or other metal foil. [0003] In use, the coloring strip is placed underneath several selected hair follicles. The end of the coloring strip is positioned as closely as possible to the scalp. The coloring material is applied to the selected hair follicles. A highlight board may be used as support. The coloring strip is then folded in half. [0004] Many stylists prefer coloring strips that will remain closed upon folding, and which are non-absorbent. Metals foils and certain plastics meet these requirements. Some coloring strips are designed to stick to themselves upon folding. [0005] Hair coloring chemicals and materials are time sensitive. That is, the hair coloring material is designed to be left in the hair for a preferred period of time. It is important for the hairstylist to be able to quickly and efficiently remove the coloring strips, and the attendant coloring material, since numerous coloring strips may be used for a single client. A goal of the present invention is to provide a device and method of hair coloring using hair coloring strips, wherein the coloring strips are easy to install, and easy to remove, while also providing for efficient hair coloring. SUMMARY OF THE INVENTION [0006] The present invention is a hair coloring strip having an appendage that extends to an exterior of the coloring strip. The appendage is affixed to the coloring strip so that, when the appendage is pulled by manual pressure, the hair coloring strip is released from the hair of the client for easy removal. DESCRIPTION OF THE DRAWINGS [0007] FIG. 1 shows a first embodiment of the hair coloring strip of the present invention. [0008] FIG. 2 shows a second embodiment of the hair coloring strip of the present invention. [0009] FIG. 3 a shows the hair coloring strip on the present invention in position in a client's hair. [0010] FIG. 3 b shows the hair coloring strip of the present invention in position in the client's hair, with the appendage in position for removal. [0011] FIG. 4 a shows the hair coloring strip on the present invention in position in a client's hair. [0012] FIG. 4 b shows the hair coloring strip of the present invention in position in the client's hair, with the appendage in position for removal. DESCRIPTION OF THE PREFERRED EMBODIMENTS [0013] The term “appendage” is used herein to indicate a smaller elongated member that projects from a larger body, which is the coloring strip. As shown in FIG. 1 , the coloring strip 2 has a smaller, but longer, appendage that extends from the coloring strip. The appendage is in the form of a string 4 . In FIG. 2 , the coloring strip 6 has an appendage in the form of a smaller elongated tail 8 that extends from the larger coloring strip. [0014] As used herein, the term “interior of the coloring strip” refers to the portion of the coloring strip in which the hair is contained after the coloring strip is folded as in FIG. 3 or FIG. 4 . The “exterior of the strip” means the side of the coloring strip that is on a side of the coloring strip that is opposite the interior of the coloring strip, and is external to the hair. Each of the interior and exterior of the coloring strip have a top and a bottom after folding. [0015] FIG. 1 shows the coloring strip having an appendage 4 attached thereto. The coloring strip may be formed of aluminum foil, a plastic sheet, or other sheets of material. A preferred material is a substantially transparent material that resists absorption of the coloring material, such as transparent Mylar. The appendage of FIG. 1 is a string which is attached in substantially the center of the exterior of the coloring strip. The string may be attached by an adhesive, or by an adhesive coated strip 10 . The string may be attached by a fastener. By way of example, the coloring strip may be 15 to 35 cm. long, with a width of 7.5 to 12.5 cm, and having a string of 20 to 35 cm. It is preferred that the string have a length that is in excess of the length of the coloring strip. [0016] The coloring strip shown in FIG. 2 has an appendage in the form of a tail that extends from one end of the coloring strip. Again, the coloring strip may be formed of aluminum foil, plastic sheets or other suitable materials. It is preferred that the coloring strip is formed of a transparent material that will not absorb the coloring material. The coloring strip in FIG. 2 is formed as a unitary member, such as by cutting the coloring strip from a larger piece of material, so that the appendage extends from one end of the coloring strip. By way of example, the coloring strip is 15 to 35 cm. long, with a width of 7.5 to 12.5 cm, with an appendage extending therefrom that is 10 to 30 cm inches in length. In the embodiment as shown in FIG. 2 , the appendage has substantially the same length as the coloring strip, and after folding, is twice as long as the coloring strip. [0017] FIG. 3 a and FIG. 3 b show a plurality of coloring strips in position on the client's hair. The coloring strip of FIG. 3 a and FIG. 3 b is the coloring strip according to the embodiment of FIG. 2 . In use, the coloring strip 6 is positioned underneath several strands of hair 12 , and the coloring material is coated on the hair that is selected and positioned over the coloring strip. The first end of the coloring strip is positioned underneath the selected hair, and as close to the scalp as possible, so that the coloring material reaches to the roots of the hair follicles. After the coloring material is applied, the coloring strip is folded as shown in FIG. 3 a . The coloring strip is folded substantially in half, so that a first end of the coloring strip meets an opposite end of the coloring strip. The selected hair is present within the interior 14 of the coloring strip. The appendage extends to an exterior 16 of the coloring strip, and is of sufficient length to extend beyond, and hang below, the coloring strip as shown in FIG. 3 a . When the embodiment of the coloring strip according to the present invention of FIG. 2 is used, one end of the appendage extends from an upper end of the coloring strip when folded, and extends along the upper exterior portion of the coloring strip, so that an opposite end of the appendage extends below the coloring strip. [0018] After the coloring strip is in position for the appropriate time for the coloring materials to sufficiently color the hair, the coloring strips are removed. The coloring strips may be removed by pulling an end of the appendage 8 as shown in FIG. 3 b , such as by gripping the appendage between the thumb and the forefinger. The coloring strips may be removed one at a time, and may be removed rapidly because of the ease of removing the coloring strips by pulling on the appendage. Alternatively, several of the strips may be grasped and pulled simultaneously. The coloring strips as shown in FIG. 3 a are removed by the upper portion of the folded strip being pulled away from the lower portion, so that the hair of the client is not pulled in a manner that is painful to the client. [0019] FIG. 4 a and FIG. 4 b show coloring strips according to the embodiment of FIG. 1 in position in the client's hair. Again, strands of hair 12 are selected, and placed over the coloring strip 2 , with one end of the coloring strip as close to the scalp as possible. The coloring material is applied, and the coloring strip is folded over the hair, so that a first end of the coloring strip meets an opposite end of the coloring strip, and the hair is retained in an interior 22 of the coloring strip. In this embodiment, the appendage is a string 4 that is attached to, and extends from, an exterior 24 of the coloring strip at approximately the mid-point of the coloring strip, such as by an adhesive strip 10 . [0020] After the coloring material has acted upon the hair of the client for an appropriate amount of time, the coloring strips are removed by pulling on the appendage or string as shown in FIG. 4 b . The coloring strips may be removed by pulling the appendages away from the client as shown in FIG. 4 b , either as a group or one at a time. The appendages of the preferred embodiments allow for rapid removal of the coloring strips, and minimize or avoid exposure of the operator to the coloring material while removing the strips. [0021] It is preferred that the coloring strips are substantially transparent, so that the hair stylist can see the change in the hair coloring through the coloring strips. It is also preferred that the strings of the embodiment in FIG. 1 are of different colors. It is typical in hair coloring to color the hair different shades in different places on the hair. For example, many clients like their hair to be lighter closer to the face, and darker toward the back of the head. The coloring may be varied according to materials used, timing and the like. The use of multiple colored strings allows that hair stylist to know which coloring strips are being used with various coloring materials. Use of multiple colored appendages allow the color coding system to be used with the device.

A hair coloring strip having an appendage that extends to an exterior of the coloring strip. The appendage is affixed to the coloring strip so that, when the appendage is pulled by manual pressure, the hair coloring strip is released from the hair of the client for easy removal.

FIELD OF THE INVENTION [0001] The present invention generally relates to a phased array antenna assembly, adapted for reducing severe radiation hazards to the human body. This antenna assembly is useful for transmitting and receiving signals while taking into account the indoor electromagnetic field strength. The present invention specifically relates to a phased array antenna assembly comprising the following three components: micro-strip small-size antenna, switching device and a controller. More specifically, and according to one particular embodiment of the present invention, the aforesaid phased array antenna assembly has proved useful in mirroring and/or doubling transmitted beams. BACKGROUND OF THE INVENTION [0002] Momentum gained in the last decade, including the introduction of mobile vehicular communication systems, is being fully exploited in an international effort to realize the personal communication services (PCS) of tomorrow. In the envisioned PCS, each subscriber carries a pocketsize communication device with an associated personal telephone number. An intelligent global network locates the individual and supervises two-way wireless transmissions which may involve speech, data, fax, and, video streams. [0003] The most important aspect of PCS is wireless communication inside buildings, where people spend most of their time. In a typical wireless indoor application, transmission takes place over a radio link ranging from a few meters to a few tens of meters. Indoor radio propagation, however, is more complicated than transmission between an earth station and a spaceship millions of kilometers away. Signals received inside a building suffer from serious distortions caused by multipath dispersion, and are usually severely attenuated. The channel is dynamic, with its properties changing over space (motion of the portable unit itself) and over time (motion of people and objects around the wireless potable unit). Detailed characterization of the propagation medium is essential in successful design of indoor communication systems. [0004] In a typical indoor portable wireless system, a basestation with a fixed antenna (AP) is installed in an elevated position and communicates with a number of portable/fixed radios (Stations) inside the building. Due to reflection and scattering of radio waves by structures inside a building, the transmitted signal most often reaches the receiver by more than one path, resulting in a phenomenon known as multipath fading. The signal components arriving from indirect paths and the direct path (if it exists) combine and produce a distorted version of the transmitted signal. In narrow-band transmission, the multipath medium causes fluctuations in the received signal envelope and phase. In wide-band pulse transmission, on the other hand, the effect is to produce a series of delayed and attenuated pulses (echoes) for each transmitted pulse. This is illustrated in FIGS. 1A and 1B , wherein the channel's responses at two points in the three-dimensional space are displayed. FIG. 1A presents a point with low delay spread, while FIG. 1B presents a point with a larger delay spread. Both analog and digital transmissions suffer from severe attenuation by the intervening structure. The received signal is further corrupted by other unwanted random effects: noise and co-channel interference. [0005] Multipath fading seriously degrades the performance of communication systems operating inside buildings. Unfortunately, little can be done to eliminate multipath disturbances. However, if the multipath medium is well characterized, the transmitter and receiver can be designed to “match” the channel and to reduce the effect of; these disturbances. Detailed characterization of radio propagation is therefore a major requirement for successful design of indoor communication systems. [0006] Propagation of radio waves inside a building is a highly complicated process. The impulse response approach described here can be used to characterize the channel. A study of the literature shows that the number of multipath components in each impulse response profile, N, is a random variable. Mean value of N is different for different types of buildings. The path variable sequences {a k }, {t k }, θ k for every point in space are random sequences. The mean and variance of the distribution of a k s are also random variables due to large-scale in homogeneities in the channel over large areas. [0007] Adjacent multipath components of the impulse response profile are dependent. A standard Poisson hypothesis is inadequate to describe the arrival-time sequences. Adjacent amplitudes are likely to have correlated fading for high resolution measurements, since a number of scattering objects that produce them may be the same. Phase components for the same profile, however, are not correlated since at frequencies of interest their relative excess range is much larger than a wavelength. The amplitude sequence and the arrival-time sequence are correlated because later paths of a profile go through multiple reflections and hence experience higher attenuation. [0008] The impulse response profiles for points that are close in space are correlated since the structure of the channel does not change appreciably over very short distances. Spatial correlation governs the amplitudes, the arrival-times and the phases, as well as the mean and variance of the amplitudes. There are small-scale local changes in the channel's statistics and large-scale global variations due to shadowing effects and spatial non-stationarities. [0009] Path loss in an indoor environment is very severe most of the time. It is also very dynamic, changing appreciably over short distances. Simple path loss rules are successful in describing the mobile channel, but not the indoor channel. [0010] The parameters of the channel depend greatly on the shape, size and construction of the building. Variations with frequency are also significant. [0011] In its more general form the channel is non-stationary in time. Temporal variations are due to the motion of people and equipment around both antennas. [0012] Any realistic channel model should consider the above factors. Furthermore, it should derive its parameters from actual field measurements rather than basing them on simplified theory. [0013] A known and a convenient model for characterization of the indoor channel is the discrete-time impulse response (i.e., DTIR) model. In this DTIR model the time axis is divided into minor intervals called “bins”. Each bin is assumed to contain either one multipath component, or no multipath component. The possibility of more than one path in a bin is excluded. A reasonable bin size is the resolution of the specific measurement since two paths arriving within a bin cannot be resolved as distinct paths. According to the DTIR model, each impulse response is described by a sequence of “0”s and “1”s (the path indicator sequence), wherein a “1” indicates the presence of a path in a given bin and a “0” represents the absence of a path in that bin. Each “1”, has an associated amplitude and a phase value. [0014] The advantage of this model is that it greatly simplifies any simulation process. It has been used successfully in the modeling and the simulation of the mobile-radio propagation-channel. Analysis of system performance is also easier with a discrete-time model, as compared to a continuous-time model. [0015] When a single unmodulated carrier (constant envelope) is transmitted in a multipath environment, due to vector addition of the individual multipath components, a rapidly fluctuating CWS envelope is experienced by a receiver in motion. To deduce this narrow-band result from the above wide-band model we let s(t) of (4) be equal to 1. Excluding noise, the resultant CWS envelope R and phase φ for a single point in space are thus given by equation 1: R ⁢   ⁢ ⅇ jφ = ∑ k = 0 ∞ ⁢   ⁢ a k ⁢ ⅇ jθ k ( 1 ) Sampling the channel's impulse response frequently enough, one should be able to generate the narrow-band CWS fading results for the receiver in motion, using the wide-band impulse response model. [0016] The impulse response approach described in the previous section is supplemented with the geometrical model of FIG. 2 . The signal transmitted from the base reaches the portable radio receivers via one or more main waves. These main waves consist of a line-of-sight, i.e., LOS (1) ray and several rays reflected (2) or scattered by main structures such as partitions (3), outer walls, floor (4), ceilings, etc. The LOS wave may be attenuated by the intervening structure to an extent that makes it undetectable. The main waves are randomized upon arrival in the local area of the portable. They break up in the environment of the portable due to scattering by local structure and furniture. The resulting paths for each main wave arrive with very short delays, experience about the same attenuation, but have different phase values due to different path lengths. The individual multipath components are added according to their relative arrival times, amplitudes, and phases, and their random envelope sum is observed by the portable. The number of distinguished paths recorded in a given measurement, and as a given point in space, depends on the shape and structure of the building, and on the resolution of the measurement setup. [0017] The impulse response profiles collected in portable site i and portable site j of FIG. 3 are normally very different due to differences in the intervening (base to portable) structure, and differences in the local environment of the portables. FIG. 4 schematically presents stations/mobiles at different locations compared to the access point (i.e., ‘AP’) wherein some of the stations are mobile and some are stationary. [0018] Variations in the statistics are now described. Let X ijk ( i= 1, 2, . . . , N; j= 1, 2, . . . , M; k= 1, 2, . . . , L )   (2) be a random variable representing a parameter of the channel at a fixed point in three dimensional space. For example, X ijk may represent amplitude of a multipath component at a fixed delay in the wide-band model, amplitude of a narrow-band fading signal, the number of detectable multipath mean excess delay or delay spread, etc. The index k in X ijk numbers spatially adjacent points in a given portable site of radius 1-2 m. These points are very close (in the order of several centimeters or less). The index j numbers different sites with the same base-portable antenna separations, and the index i numbers groups of sites with different antenna separations. [0019] With the above notations, there are three types of variations in the channel. The degree of these variations depends on the type of environment, distance between samples, and on the specific parameter under consideration. For some parameters, one or more of these variations may be negligible. [0020] It is acknowledged that for small-scale variations, a number of impulse response profiles collected in the same “local area” or site are broadly similar since the channel's structure does not change appreciably over short distances. Therefore, impulse responses in the same site exhibit only variations in details. With fixed i and j, X ijk (k=1, 2, . . . , L) are correlated random variables for close values of k. This is equivalent to the correlated fading experienced in the mobile channel for close sampling distances. [0021] It is further acknowledged that for mid-scale variations, this is a variation in the statistics for local areas with the same antenna separation. As an example, two sets of data collected inside a room and in a hallway, both having the same antenna separation, may exhibit great differences. If μ ij denotes the mathematical expectation of X ijk (i.e., μ ij =E k (X ijk ), where E k denotes expectation with respect to k), then for fixed i, μ ij is a random variable. For amplitude fading, this type of variation is equivalent to the shadowing effects experienced in the mobile environment. Different indoor sites correspond to intersections of streets, as compared to mid-blocks. [0022] It is lastly acknowledged that for large-scale variations, the channel's structure may change drastically, when the base to portable distance increases, among other reasons due to an increase in the number of intervening obstacles. As an example, for amplitude fading, increasing the antenna separation normally results in an increase in path loss. Using the previous terminology ε(d i )=E jk (X ijk )=E j (μ ij ) is different for different d i s, if X ijk denotes the amplitude, this type of variation is equivalent to the distance dependent path loss experienced in the mobile environment. For the mobile channel ε(d) is proportional to d −n , where d is the base-mobile distance and n is a constant. [0023] A comparison between the indoor and the mobile channels is now provided. The indoor and outdoor channels are similar in their basic features: they both experience multipath dispersions caused by a large number of reflectors and scatters. They can both be described using the same mathematical model. However, there are also major differences, briefly described in this section. [0024] The conventional mobile channel (with an elevated base-station and low-level mobile/fixed station) is stationary in time and non-stationary in space. Temporal stationary is because signal dispersion is mainly caused by large fixed objects (buildings). In comparison, the effect of people and vehicles in motion are negligible. The indoor channel, on the other hand, is not stationary in space or in time. Temporal variations in the statistics of the indoor channel are due to the motion of people and equipment around the low-level portable antennas. [0025] The indoor channel is characterized by higher path losses and sharper changes in the mean signal level, as compared to the mobile outdoor channel. Furthermore, applicability of a simple negative-exponent distance-dependent path loss model well established for the mobile channel is not universally accepted for the indoor channel. [0026] Rapid motions and high velocities typical of the mobile users are absent in the indoor environment. The Doppler shift of the indoor channel is therefore negligible. [0027] Maximum excess delay for the mobile channel is typically several microseconds if only the local environment of the mobile is considered, and more than 100 μs if reflection from distant objects such as hills, mountains, and city skylines is taken into account. The outdoor rms delay spreads are of the order of several μs without distant reflectors, and 10 to 20 μs with distant reflectors. The indoor channel, on the other hand, is characterized by excess delays of less than one μs and rms delay spreads in the range of several tens to several hundreds of nanoseconds (most often less than 100 ns). Therefore, for the same level of inter-symbol interference, transmission rates can be much higher in the indoor environments. [0028] Finally, the relatively large outdoors-mobile transceivers are powered by the battery of the vehicle with an antenna located away from the mobile user. This is in contrast with lightweight portables normally operated close to the user's body. Therefore, much higher transmitted powers are feasible in the outdoors-mobile environment. SUMMARY OF THE INVENTION [0029] It is the purpose of the present invention to present a phased array antenna assembly, adapted for reducing severe radiation hazards to the human body. This antenna assembly is useful for transmitting and receiving signals while taking into account the indoor electromagnetic field strength. Said antenna design comprises the following three components: micro-strip small-size antenna, switching device and a controller. Significantly and most importantly, the said provided assembly is cost effectively adapted for indoor mass-utilization, consisting of low cost materials and components. Additionally, said assembly was proved to radiate a limited electromagnetic field in a minimal measure required for communication. [0030] The said switching device has a communicating means with said antenna to select between receiving or transmitting modes. In addition, said switching device further possesses a selecting means for phase shift and the receiving/transmitting frequencies. [0031] The aforementioned controller is adapted to receive inputs from said switching device. It is comprised of coordinating means and a suitable memory. The said coordinating means is adapted to interconnect said switching device with algorithm-based software. The said memory queue records the optimal path in each indoor environment to each of the associated nodes to said antenna assembly. [0032] It is also in the scope of the present invention to provide the novel antenna as defined above, wherein the indoor electromagnetic field is located in a closed construction selected from house, apartment, large vehicle, aircraft or ship, industrial space, hospital or office and further wherein said closed construction comprises a plurality of openings. Additionally or alternatively, the said closed construction is preferably comprised of obstacles selected from corridors, floors, ceiling, windows, doors or any combination thereof. The openings are preferably selected from corridors, floors, ceiling, windows, doors or any combination thereof, and further wherein said openings are the wave guide slots. [0033] It is further in the scope of the present invention wherein the antenna assembly defined above is characterized by the fact that that the path loss (L) of the electromagnetic radiation is calculated by the equation:   L   ⁢ 1 = ⁢ 32.1 - 20 ⁢   ⁢ log   ⁢ 10 ⁢ ( χ ⁢  R   ⁢ n  ) - 20 ⁢   ⁢ log ⁡ [ 1 ⁢   -   ⁢ ( χ ⁢   ⁢ R   ⁢ n ) 2   ⁢ 1 ⁢   +   ⁢ ( χ ⁢   ⁢ R   ⁢ n ) 2 ] + ⁢ 17.8 ⁢ log   ⁢ 10 ⁡ ( X ) + 8.6 ⁢ log   ⁢ 10 ⁢ { - ln ⁢  R   ⁢ n ⁢ χ  · ( π ⁢   ⁢ n   ⁢ d ) · ( X   ⁢ ρ   ⁢ bn ( 0 ) ⁢   ⁢ d ) } wherein n is the mode number; Rn is the reflection factor for mode number n, and Kn is the wave R n = K n - kZ EM K n + kZ EM number for mode n, ρ—(Rho) denoted as any other received signal like S(t) before and X is the real part of the channel output Y. More specifically, said antenna assembly is potentially characterized by the fact that Rn is the reflection factor for mode number n, and Kn is the wave number for mode n. Additionally or alternatively, the aforementioned antenna assembly is characterized by the fact that the antenna creates a main beam lobe, in such a manner that Pant=P0+Pls and Pls=f(L1*Krssi); wherein P0−0 dBm, and Pls−Path loss to the mobile. [0034] It is also in the scope of the present invention wherein an ASIC protocol controls the antenna operation in such a manner that the antenna is adapted to fit with any RF protocol. Thus, according to one embodiment of the present invention, the said ASIC may comprise an algorithm consisting of the following steps: (a) scanning with the first beam for first station; (b) receiving a signal and writing the RSSI; (c) proceeding to next beam direction; (d) getting a max. RSSI or received field strength from said station; (e) calculating the station virtual distance from the said antenna and adjusting the power level to the correct one; (f) registering the obtained RSSI and/or level in a memory, wherein the obtained is associated with the beam direction and with the station ID; and then (g) scanning for a plurality of other stations as required (See FIG. 6 ). Preferably, said sequence additionally consists of the step of proceeding with other receiving and/or transmitting tasks. [0035] According to a particular embodiment of the present invention, the antenna assembly as defined above is characterized by the fact that the calculating step is based on the electromagnetic radiation equation:   L   ⁢ 1 ⁢   = ⁢ 32.1 ⁢   -   ⁢ 20 ⁢   ⁢ log   ⁢ 10 ⁢   ⁢ ( χ ⁢   ⁢  R   ⁢ n  ) ⁢   -   ⁢ 20 ⁢   ⁢ log ⁡ [ 1 ⁢   -   ⁢ ( χ ⁢   ⁢ R   ⁢ n ) 2   ⁢ 1 ⁢   +   ⁢ ( χ ⁢   ⁢ R   ⁢ n ) 2 ] ⁢   + ⁢   ⁢ 17.8 ⁢   ⁢   ⁢ log   ⁢ 10 ⁢ ( X ) ⁢   +   ⁢ 8.6 ⁢   ⁢   ⁢ log   ⁢ 10 ⁢   ⁢ { - ln ⁢   ⁢  R   ⁢ n ⁢   ⁢ χ  ·   ⁢ ( π ⁢   ⁢ n   ⁢ d ) ·   ⁢ ( X   ⁢ ρ   ⁢ bn ( 0 ) ⁢   ⁢ d ) } wherein n is the mode number; Rn is the reflection factor for mode number n, and Kn is the wave number for mode n. [0036] It is also in the scope of the present invention to provide a useful antenna assembly, characterized by the fact that the antenna used is a cell-wall socket (CWS). Preferably, according to another preferred embodiment of the present invention, the antenna assembly is adapted to indoor utilizations, wherein either the antenna or its associated clients are interconnected to at least one common network. [0037] It is also in the scope of the present invention wherein the network is implemented in a plurality of closed constructions, in such a manner that a network of one closed construction is in communication with at least one other network located in at least one other closed construction, and wherein a master operator (e.g., said CWS) coordinates and/or communicates between a plurality of sub-networks. [0038] It is also in the scope of the present invention wherein the antenna assembly as defined above, is characterized by the fact that while one master CWS is busy with an on-going session, selected from any fax, voice, data transaction or any combination thereof, another CWS is used as the coordinating master. [0039] According to another aspect of the present invention, the calling device will identify itself by means of its personal identification number (PIN) to the CWS. The free CWS will install the PIN as the calling party number for the exchange. This will cause correct billing of the PIN owner. [0040] It is still according to the main core of the present invention, wherein the aforementioned antenna assembly comprises a phased array antenna. Said antenna is comprised of n by m elements with horizontal-vertical and circular polarization. Hence, the present invention claims a phased array antenna, as schematically presented in the appended figures, and especially as described and defined in FIG. 9 and FIG. 10 . [0041] It is further according to another aspect of the present invention, wherein a broadband antenna assembly, as defined in any of the above, is adapted to operate at a frequency within the band gap of about 900 Mhz to about 6 Ghz. More particularly, said broadband antenna is adapted to operate at a frequency within the band gap of about 2.4 GHz to about 5.8 Ghz. [0042] It is another object of the present invention to provide an antenna assembly as defined in any of the above, especially adapted for mirroring a plurality of main beam lobes. The symmetry of the mirrored beams is referred to at least one predetermined axis of the plate that comprises the element array. It is according to one embodiment of the present invention that the aforesaid axis is perpendicular to the plate that comprises the element array. [0043] It is another object of the present invention to provide a phased array antenna, as defied in any of the above, wherein at least a portion of the switching modules is in series. Alternatively or additionally, at least a portion of said switching modules is parallel. [0044] It is another object of the present invention wherein the switching module is an electronic circuit comprising inter alia a plurality of p RF signal inlets, a plurality of q RF signal outlets and a plurality of p+q diodes, wherein q and q are any positive integer numbers; in such a manner that each of said p+q diodes interconnects one of the q inlets with n outlets; wherein n is any positive integer so that 1≦n≦q; and/or more specifically, wherein p=q=2n. [0045] It is another object of the present invention wherein the switching module is an electronic circuit comprising inter alia a plurality of p RF signal inlets, a plurality of q RF signal outlets and a plurality of p+q−1 diodes; wherein q and p are any positive even integer numbers; each of said p+q diodes interconnects one of the q inlets with n outlets wherein is 1≦n≦q so that at least one beam is not mirrored. [0046] It is another object of the present invention wherein the switching module is an electronic circuit comprising inter alia al plurality of q+1 RF signal inlets, a plurality of q+1 RF signal outlets and a plurality of (p+1)q diodes; wherein q is any even integer number in such a manner that each of said pq diodes interconnects one of the q inlets with p outlets; wherein a single central beam is not mirrored; wherein p is an integer number, and further wherein is 1≦p≦q. [0047] It is another object of the present invention tp provide a useful antenna system, especially adapted for mirroring a plurality of L main beam lobes; the symmetry of the mirrored beams is referred to a predetermined axis of the plate that comprises the element array; said antenna comprising inter alia p RF input/outputs; the q inlets are interconnected with j outlets by means of each of said p+q diodes; at least one RF switch; a plurality of 1:L splitter modules; an array of n by m elements with horizontal-vertical and or circular polarization and a plurality of s switching modules adapted for mirroring said plurality of L main beam lobes; wherein s, L, D are denoted as the signal, beam and diodes and further wherein n, m, i and j are any positive integer numbers, and so that is=2iB=4iD. [0048] Lastly, it is another object of the present invention to provide a novel and cost-effective switching module which is especially adapted to double RF signals in power of p. The module, e.g., module ( 1110 ) presented schematically in FIG. 11 , is comprised inter alia of a plurality of q RF signal inlets, a plurality of q RF signal outlets and a plurality of q diodes; wherein q is any integer number in such a manner that each of said q diodes interconnects one of the q inlets with pq outlets; wherein p is an integer number, and wherein is 1≦p≦q. BRIEF DESCRIPTION OF THE FIGURES [0049] In order to understand the invention and to see how it may be carried out in practice, a preferred embodiment will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which [0050] FIG. 1A schematically presents a point with low delay spread while FIG. 1 b presents a point with a larger delay spread; [0051] FIG. 2 schematically presents multipath from one CWS to three Stations; [0052] FIG. 3 schematically presents a time varying power at different signal level; [0053] FIG. 4 schematically presents stations/mobiles at different locations compared to the AP; [0054] FIG. 5 schematically presents the ASIC and antenna block diagram; [0055] FIG. 6 schematically presents an ASIC protocol controlling the antenna operation; [0056] FIG. 7 schematically presents several CWS nodes which form a master to master Ad-hoc network; [0057] FIG. 8 schematically presents a whole apartment with three typical applications; [0058] FIG. 9 schematically presents a CWS phased array antenna comprised of four horizontal radiating elements denoted by the letters A;B;C;D; [0059] FIG. 10 schematically presents an indoor phased array antenna; [0060] FIG. 11 schematically presents a four beam switched phased array, characterized by an N×M arrayed antenna construction; [0061] FIG. 12 schematically presents a second novel system and method according to yet another embodiment of the present invention for mirroring a plurality of beams; and, [0062] FIG. 13 schematically presents a third novel system and method according to another embodiment of the present invention for mirroring a plurality of beams. DETAILED DESCRIPTION OF THE INVENTION [0063] The following description is provided, alongside all chapters of the present invention, so as to enable any person skilled in the art to make use of said invention and sets forth the best modes contemplated by the inventor of carrying out this invention. Various modifications, however, will remain apparent to those skilled in the art, since the generic principles of the present invention have been defined specifically to provide the antenna assembly as defined and described below. [0064] This invention allows any fixed or portable device to adjust the phased array switching antenna beam directly to the source of the communication and calculate the exact power needed to reach the desired destination with the included equations. To date, the solution will cost below 10 dollars in mass production. [0065] The present invention provides a mathematical modeling of the channel. Thus, the novel impulse response approach is hereto presented. The complicated random and time-varying indoor radio propagation channel can be modeled in the following manner: for each point in the three-dimensional space, the channel is a linear time-varying filter with the impulse response given by equation 3: h ⁡ ( t , τ ) = ∑ k = 0 N ⁡ ( τ ) - 1 ⁢ a k ⁡ ( t ) ⁢ δ ⁡ [ τ - τ k ⁡ ( t ) ] ⁢ ⅇ jθ k ⁡ ( t ) ( 3 ) wherein t and τ are the observation time and application time of the impulse, respectively, N(τ) is the number of multipath components, {a k (t)}, {τ k (t)}, {θ k (t)} are the random time varying amplitude, arrival-time, and phase sequences, respectively, and δ is the delta function. [0066] The channel is completely characterized by these path variables. This mathematical model is illustrated below. It is a wide-band model, which has the advantage that, because of its generality, it can be used to obtain the response of the channel to the transmission of any transmitted signal s(t) by convolving s(t) with h(t) and adding noise. [0067] The time-invariant version of this model has been used successfully in mobile radio applications. For the stationary (time-invariant) channel, equation (4) is reduced to: h ⁡ ( t ) = ∑ k = 0 N ⁡ ( τ ) - 1 ⁢ a k ⁢ δ ⁡ [ t - t k ] ⁢ ⅇ jθ k ( 4 ) [0068] The output y(t) of the channel to a transmitted signal s(t) is therefore given by equation 5: y ⁡ ( t ) = ∫ - ∞ ∞ ⁢ s ⁡ ( τ ) ⁢ h ⁡ [ t - τ ] ⁢   ⁢ ⅆ τ + n ⁡ ( t ) ( 5 ) where n(t) is the low-pass complex-valued additive Gaussian noise. With the above mathematical model, if the signal: x ( t )= Re{s ( t ) e jω 0 t }  (6) is transmitted through this channel environment (wherein s(t) is any low-pass signal and ω 0 is the carrier frequency), the signal y ( t )= Re{τ ( t ) e jω 0 t }  (7) is received, where instead of the integral we can write equation 8: ρ ⁡ ( t ) = ∑ k = 0 N - 1 ⁢ a k ⁢ s ⁡ [ t - t k ] ⁢ ⅇ jθ k + n ⁡ ( t ) ( 8 ) [0069] In a real-life situation, a portable receiver moving through the channel experiences a space−varying fading phenomenon. One can therefore associate an impulse response “profile” with each point in space. It should be noted that profiles corresponding to points close in space are expected to be broadly similar because principle reflectors and scatters, which give rise to the multipath structures, remain approximately the same over short distances. [0000] The Indoor Electromagnetic Equations [0070] Thus, most surprisingly, a novel and most effective micro-strip small-size and low-cost phased array antenna design is provided by the present invention. Said antenna design, which takes into account the indoor electromagnetic field strength is hence hereto presented. The normal house, apartment or office is divided into areas that are similar to a waveguide. The doors and windows are the waveguide slits. The path loss is calculated by the following new equations (9-10):   L   ⁢ 1 ⁢   = ⁢ 32.1 ⁢   -   ⁢ 20 ⁢   ⁢ log   ⁢ 10 ⁢   ⁢ ( χ ⁢   ⁢  R   ⁢ n  ) ⁢   -   ⁢ 20 ⁢   ⁢ log ⁡ [ 1 ⁢   -   ⁢ ( χ ⁢   ⁢ R   ⁢ n ) 2   ⁢ 1 ⁢   +   ⁢ ( χ ⁢   ⁢ R   ⁢ n ) 2 ] ⁢   + ⁢   ⁢ 17.8 ⁢   ⁢   ⁢ log   ⁢ 10 ⁢ ( X ) ⁢   +   ⁢ 8.6 ⁢   ⁢   ⁢ log   ⁢ 10 ⁢   ⁢ { - ln ⁢   ⁢  R   ⁢ n ⁢   ⁢ χ  ·   ⁢ ( π ⁢   ⁢ n   ⁢ d ) ·   ⁢ ( X   ⁢ ρ   ⁢ bn ( 0 ) ⁢   ⁢ d ) } ( 9 ) wherein n is the mode number; L is the path loss is dB; Rn is the reflection factor for mode number n; and Kn is the wave number for mode n. R n = K n - kZ EM K n + kZ EM ( 10 ) [0071] The antenna creates a main beam lobe that has only the right amount of field strength, which is calculated by (11): Pant=P 0 +Pls Pls=f ( L 1 *Krssi )   (11) wherein: P0−0 dBm (i.e, 1 mWatt/50 Ohm) and Pls−Path loss to the mobile. [0072] In this way the antenna radiates only to the desired direction and does not pollute the whole space with unnecessary radiation. Secondly, the radiated power is always the only power that is needed to get to the certain mobile or fixed device and not more. This directed power is hence provided in order to reduce the human body exposure to EM radiation. [0000] ASIC Protocol [0073] FIG. 5 presents the ASIC and antenna block diagram. The ASIC includes the interfaces, processor and flash memory wherein the specific software for the antenna-switching algorithm resides. Flash Memory is referred to in the present invention as a variant on EEPROMs where banks of the chip are erased at once. This type of chip has become popular for computer ROMs, offering “easy” field reprogramming. The term ASIC refers to the known Application-Specific Integrated Circuit. The terms ARM or NEO refer to any commercially available microprocessor useful also for computing devices. Lastly, the term MAC (Media Access Control) address refers to a unique hardware number of a device. [0074] Reference is made now to FIG. 6 , presenting an ASIC protocol which controls the antenna operation. The ASIC and the antenna are adapted to fit with any RF protocol. A block diagram of the ASIC and the antenna are shown in the following block diagram: [0075] The ASIC sends a control word to change the beam direction to the RF antenna head when the channel is not the optimum one, and in case of active scanning for a new mobile/or fixed station. [0076] The ASIC performs the following MBF algorithm: 1. Scan with the first beam for first station; 2. If receives a signal, write the RSSI; 3. Go to next beam direction; 4. Get maximum. RSSI or received field strength from that station; 5. Calculate the station virtual distance from the CWS using the electromagnetic equations as defined above, preferably in eq. (9); 6. Adjust the power level to the correct one; 7. Register in a table, the beam direction associated with that station ID; 8. Scan for next station; and, 9. After scan complete, proceed with other Rx/Tx tasks. [0086] It is acknowledged in this respect that the smart antenna as defined in paragraph (e) is preferably a cell-wall socket (CWS) product. Hence, the said CWS is a wall-installed unit, comprising the element as defined in any of the above. [0000] Wireless Pico Net Master to Master Ad-hoc Association: [0087] The present invention generally relates to any indoor utilizations, wherein the indoor electromagnetic field radiated by either the aforementioned antenna or any of its clients is located in a closed construction selected from house, apartment, large vehicle, aircraft or ship, industrial space or office, and further wherein said closed construction comprises a plurality of openings. It is acknowledged in this respect that either the antenna or its associated clients are interconnected to a common network, denoted herby by the short term ‘network’. Reference is hence made to FIG. 7 , schematically presenting several CWS nodes, which form a master-to-master ad-hoc network. [0088] It is further in the scope of the present invention wherein said network is implemented in a plurality of closed constructions, as defined above, such that a network of one closed construction is to be in communication with at least one another network located in at least one other closed construction. A master CWS coordinates and/or communicates between those sub-networks. Thus, said master CWS comprises a plurality of master CWS connections, hereto denoted in the present invention by the term “Trunk On Demand” (i.e., TOD). [0089] The TOD feature is required in case one master CWS is busy with an on-going session. A session can be selected from any fax/voice/data transaction. The TOD feature comes into effect only if there is another master CWS in the transmission range of the original master CWS. This other master CWS can be a second line in the same house, a close neighbor in the apartment above or below or another repeater CWS. The collection of close range connected master CWSs comprises the campus network. Any call/transaction will hop from one busy cell to the next looking for the first non-busy twisted pair towards the exchange. The calling device will identify itself with its personal identification number (PIN) to the CWS. The free CWS will install the PIN as the calling party number for the exchange. This will cause correct billing of the PIN owner. Reference is hence made to FIG. 8 showing a CWS nodes call routing. [0090] The CWS units that are based on the propagation model as defined above and the smart antenna as similarly defined above will be installed in the walls of the building. The CWS nodes will detect each other and compose the indoor wireless network. If one of the units is a CWS bridge then the network will have a way to communicate with the outside world as shown in FIG. 8 . The smart antenna will increase this range and the link will be able to penetrate walls. In order to cover a whole apartment or a building with pico-cell based CWS nodes we need to place a node every several tens of meters, such that each CWS AP can communicate with at least one other CWS. A whole apartment with three typical applications is shown in FIG. 8 . The applications are: cellular call is routed towards CWS from the car, printing from a laptop in the living room, and a refrigerator with an embedded internet enabled device. The CWS AP Master to Master nodes connections are marked in red. The end points are marked with blue links. [0091] Reference is made now to FIG. 9 , presenting a CWS phased array antenna comprised of four horizontal radiating elements denoted by the letters A;B;C;D;. The crossed circles represent hybrids and the plain circles represent phase shifting devices. As a result of inputting RF into one or more of the ports ( 1 ; 2 ; 3 ; 4 ) a different directional beam is formed as denoted by the drawings on the right. Similarly, FIG. 10 schematically presents an indoor phased array antenna. [0092] Although the block diagram is drawn for four horizontal elements, it represents a general form of n by m antenna elements, which will be realized according to changing needs in different CWS masters. It is acknowledged that according to one embodiment of the present invention, the antenna element is a basic radiating/receiving element and could be configured to horizontal/vertical/circular polarization. This drawing shows an example of the realization with eight elements (4 by 2), which may produce eight or more different beams according to the switching of the RF into the different inputs. [0093] Reference is made now to FIG. 11 , presenting a novel system and method according to one embodiment of the present invention for mirroring a plurality of main beam lobes created by the antenna assembly as defined and described in any of the above. The upper portion of FIG. 11 is a schematic top view of a four beam switched phased array ( 1180 ) characterized by an N×M arrayed antenna construction. There are K Array plates (wherein K is an integer number from 1 to k), consisting of N by M elements; wherein N is denoted for the horizontal elements (wherein N is an integer number, and further wherein N≧2) and wherein M is denoted for the vertical elements (wherein M is an integer number and further wherein M≧1). [0094] It is acknowledged in this respect that the mirroring could be provided along any axis of the plate that includes the element array, and not only perpendicular to it. Purely for the simplicity of the explanation, perpendicular mirroring is provided. FIG. 11 presents a K=2 array, which is characterized by a V shaped orientation. Here, the angle θ ( 1170 ) between the two plates of the mechanical construction equals 150 degrees. Each of the left and right doubled lobes ( 1181 , 1182 on the left and 1183 , 1184 on the right) covers each 22.5 degrees and enables the beam to cover four continuous interval states of 15 degrees. Hence, three adjacent plates with the same angle between every two are adapted to enable 90 degrees coverage with six beams. Alternatively, three adjacent plates with 120 degrees between the two plates are adapted to enable 180 degrees coverage with six beams of 30 degrees width. Moreover, swapping of two beams will form four beams in one plate; for this an extension of the switch matrix and addition of another 1:4 power splitter ( 1103 ) is required. [0095] The horizontal element or elements are made of combinations of patches, slots, dipoles etc., with any kind of feeding, e.g., serial, parallel, etc. The vertical elements could be of any kind, and may further be comprised of patches, dipoles, slots or any combination thereof. The connection between the elements could be serial or parallel or both serial and parallel. [0096] Reference is still made to FIG. 11 , showing a scheme of the electronic system of the aforesaid four beams 4 by 6 arrayed antenna ( 1100 ); wherein RF input/output ( 1101 ) is transferred via an RF switch ( 1102 ) and 1:4 splitter modules ( 1103 ) towards the left and right portions of the antenna. Hence, four inlets enter the switching modules ( 1110 ), namely 1141 - 1144 . By means of an array of 4 diodes providing a communication root characterized by a single diode per root as described in switching modules ( 1110 ), four outlets (namely 1151 - 1154 ) are in communication with the elements of the said antenna array ( 1160 ). [0097] The advantages of antenna ( 1100 ) and the like lie in saving switches, and reducing insertion loss, wherein only one switch is used in series to the RF path. It is acknowledged in this respect that a RF switch may cost about one dollar, so a significant reduction of the device's costs is hereto provided. Moreover, each such a RF switch increases the insertion loss by about 1 dB. The novel switching modules ( 1110 ) provides for one switch per root, and hence eliminates about 50% of losses due to the existence of a series of switches per root. [0098] Reference is made now to FIG. 12 , which illustrates a second novel system and method according to yet another embodiment of the present invention for mirroring a plurality of beams. The swapping between two beams is performed by switching a matrix, which is an extension of the aforesaid switching modules ( 1110 ), additionally comprising 1:4 splitter ( 1103 ). Here, angle θ is of 90 degrees, enabling the mirrored beams to cover four continuous interval states of 25 degrees. According to another embodiment of the present invention, four adjacent plates are provided for forming a square shape, which enables 90 degrees coverage with four beams. [0099] Reference is made now to FIG. 13 , which illustrates a third novel system and method according to another embodiment of the present invention for mirroring a plurality of beams. The swapping between the two beams is performed by switching stabs, utilizing one or more commercially available double-pole double-throw (DPDT) switches.

A novel phased array antenna assembly is hereto presented. This antenna is adapted for reducing severe radiation hazards to the human body, and is useful for transmitting and receiving signals while taking into account the indoor electromagnetic field strength. The antenna comprising a micro-strip small-size antenna; a switching device, having a communicating means with said antenna to select between receiving or transmitting modes, further having a selecting means for phase shift and the receiving/transmitting frequencies; a controller adapted to receive inputs from said switching device comprising; a coordinating means, adapted to interconnect said switching device with a algorithm-based software; and a memory queue. This antenna assembly is cost effective in the manner it is adapted for an indoor mass-utilization consisting of low cost materials and components, and further wherein said assembly radiates a limited electromagnetic field in a minimal measure required for communication.

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority from India Application Serial No. 407/CHE/2011, filed on Feb. 14, 2011, entitled A PROCESS FOR THE PREPARATION OF (R,S)—NICOTINE, which application is assigned to the same assignee as this application and whose disclosure is incorporated by reference herein. FIELD OF THE INVENTION The present invention describes a synthetic process for the preparation of (R,S)-nicotine. BACKGROUND OF THE INVENTION Nicotine, (S)-3-(1-methyl-2-pyrrolidinyl)pyridine, is an alkaloid found mainly in tobacco. Smoking of tobacco results in nicotine dependence and is habit forming. Smoking has also been associated with disease of lungs including malignant growth. There is a world-wide recognition of harmful effects of smoking. Unfortunately habitual smokers find it very hard to achieve abstinence from smoking. Further dependence on nicotine comes in the way of any effort to control smoking. To overcome this formidable issue, products containing small amounts of nicotine have been developed and are being promoted as substitutes for traditional smoking products like cigars and cigarettes. Treating nicotine dependence requires therapeutic use of nicotine. Nicotine is given to patients through dermal patches, gums, creams, lozenges, nasal sprays or electric cigarettes to wean them away from smoking. Nicotine is also therapeutically used in treating certain medical conditions such as attention deficit disorder, Tourette's syndrome, schizophrenia, Alzheimer's disease, Parkinsonism etc. The main source of nicotine is tobacco. Nicotine isolated from tobacco contains many related minor alkaloids as impurities in addition to impurities formed through degradation. European Pharmacopoeia monograph on nicotine prescribes limits for anatabine, anabasine, cotinine, myosmine, β-nicotyrine, nicotine-N-oxide and nornicotine impurities, with a maximum of 0.3% for each of these but total being limited to not more than 0.8%. British Pharmacopoeia also mentions anatabine, cotinine, myosmine, β-nicotyrine, nicotine-N-oxide as impurities. Although the USP does not mention specific impurities, a limit of 1% for all the impurities and not more than 0.5% for any one impurity is prescribed. The impurities present in natural nicotine vary depending on the geographical source of tobacco and the season in which it is collected. It is difficult to remove these impurities since they are closely related. Thus the pharmacopoeias recognize the variations in quality and quantity of impurities in natural nicotine. It was envisaged that nicotine obtained from synthetic source will be free from the impurities present in natural nicotine. Further, synthetic nicotine produced by a validated process with well characterized impurity profile should be a superior API compared to natural nicotine with its varying impurity profile. Several synthesis of (S)-nicotine are reported in the literature. Chiral center has been created by using expensive chiral intermediates such as prolinol ( J. Org. Chem. 1982, 41, 1069-1073), pivaloyl-β-D-galactosylamine ( Tetrahedron Letters, 1999, 40, 7847-7650), or using chiral catalyst ( Synlett 2009, 9, 1413-1416). However, these methods are expensive and are not suitable for industrial production. SUMMARY OF THE INVENTION Since the enantioselective synthesis is too expensive on an industrial scale, synthesis of (R,S)-nicotine followed by resolution and racemisation of unwanted (R)-nicotine was explored. The resolution of (R,S)-nicotine is reported in the literature. Aceto et al have resolved the racemic nicotine using d-tartaric acid ( J. Med. Chem. 1979, 22, 174-177). DeTraglia and Tometsko have resolved (R,S)-nicotine using Pseudomonas putida cultures ( Applied and Environmental Microbiology, 1980, 39, 1067-1069). Racemization of (S)-nicotine is also reported in the literature ( Synthetic Communications, 1982, 12, 871-879) We have developed a new and efficient process for the synthesis of (R,S)-nicotine. Together with the known methods for its resolution and racemization of the unwanted isomer, this process provides an attractive and economical method for the production of synthetic (S)-nicotine. It will be an alternative to natural nicotine, which has several disadvantages as mentioned earlier. DETAILED DESCRIPTION OF THE INVENTION The process for the preparation of (R,S)-nicotine is outlined in Scheme 3 below: The most convenient way to prepare (R,S)-nicotine is through myosmine (Scheme-3). Myosmine is hydrogenated to (R,S)-nornicotine, which on N-methylation gives (R,S)-nicotine. Myosmine has been prepared by condensing N-vinylpyrrolidone with ethyl nicotinate. ( Acta. Chem. Scand. B. 1976, 30, 93). However, preparation of N-vinylpyrrolidone involves use of acetylene gas at high temperature and pressure. N-vinylpyrrolidone is lachrymatory and irritating to the skin, lungs, and eyes. It is known to cause corneal opacity. Our efforts to find a safer alternative resulted in the selection of N-(1-Butenyl)-2-pyrrolidone (I, scheme-3) which has not been used till now to prepare myosmine. N-(1-butenyl)-2-pyrrolidone (I) is a stable, colorless liquid and is not lachrymatory. Its preparation, as reported in the literature, involves reacting butanal with 2-pyrrolidone in a solvent using p-toluenesulfonic acid as a condensing agent ( Chemistry Letters, 1992, 247-250). Sulfonic acid and its esters are considered to be potential alkylating agents that exert genotoxic effects. Because of this, use of p-toluenesulfonic acid is avoided in industrial processes. Earlier literature describes several other catalysts such as sulfuric acid and neutral or acidic alumina for condensing the aldehyde with 2-pyrrolidone ( Chemistry Letters, 1992, 247-250). In our hand, none of these catalysts gave satisfactory results. Kwon et al. had condensed (S)-ethyl pyroglutamate with butanal using phosphorous pentoxide as catalyst ( J. Org. Chem. 1992, 57, 6169-6173) to obtain (S)-ethyl-N-(1-butenyl)pyroglutamate. When we tried phosphorus pentoxide, it was found to be an excellent condensing agent and gave I in good yields. Phosphorus pentoxide is soluble in water and can be removed by alkali wash during workup to give phosphate salt, which is not injurious to health on dilution. Phosphate salts are routinely used as fertilizers and in food industry. In the next stage, I was condensed with methyl nicotinate using sodium hydride in a solvent such as THF or DMF to obtain 1-(but-1-enyl)-3-nicotinoylpyrrolidin-2-one (II) in good yields. To our knowledge II is a new molecule and is not reported in the literature till now. Reaction of II with strong mineral acid such as hydrochloric acid under heating resulted in the deprotection of amide nitrogen, followed by decarboxylation to give a primary amine intermediate which on treating with base resulted in cyclization to give myosmine. This is the first report of the preparation of myosmine starting from II. Catalytic hydrogenation of myosmine resulted in (R,S)-nornicotine. Haines et al used palladium oxide in ethanol to reduce myosmine to (R,S)-nornicotine and isolated (R,S)-nornicotine only as picrate salt ( J. Amer. Chem. Soc., 1945, 1258-1260). Jacob used sodium borohydride in methanol-acetic acid to reduce a related compound, 5-bromomyosmine to obtain racemic 5-bromo-nornicotine ( J. Org. Chem., 1982, 47, 4165-4167). Hatton et al. used palladium on activated carbon in methanol to reduce myosmine labeled with stable isotope, [6 −2 H]-myosmine to [6 −2 H]-nornicotine ( J. Label Compd. Radiopharm. 2009, 52, 117-122). After screening a number of catalysts, we selected palladium on carbon with methanol as medium. After general workup, the pure (R,S)-nornicotine was isolated by high vacuum distillation in high yields and high purity. Conversion of (R,S)-nornicotine to (R,S)-nicotine was carried out by N-methylation using formaldehyde and formic acid as reported in the literature ( J. Amer. Chem. Soc., 1993, 115, 381-387). The embodiments of the present invention are illustrated in the following examples, which are not intended in any way to limit the scope of the invention. EXAMPLES Example-1 A. Preparation of 1-(but-1-enyl)pyrrolidin-2-one (I) A solution of 2-pyrrolidone (50 g, 0.588 mol), butanal (42.4 g, 0.588 mol) and P 2 O 5 (2 g, 0.014 mol) in 300 ml toluene, were refluxed together for 10 hours using Dean-Stark apparatus to collect liberated water. The resulting solution was cooled and washed with 5% solution of sodium bicarbonate and dried over anhydrous sodium sulphate. After removing the solvent under reduced pressure, 1-(but-1-enyl)pyrrolidin-2-one (I) was obtained by distillation as a liquid. (68.2 g, 83.2%). 1 H NMR (CDCl 3 ): δ 1.02 (3H, t), 2.03-2.15 (4H, m), 2.45 (2H, t), 3.5 (2H, t), 5.01 (1H, m), and 6.85 (1H, d). 13 C-NMR (CDCl 3 ): δ 172.52, 122.91, 113.8, 45.09, 31.07, 23.03, 17.27, and 14.27. IR: 2962, 2930, 1698, 1663, 1253 Cm −1 . B. Preparation of 1-(but-1-enyl)-3-nicotinoyl-pyrrolidin-2-one (II) Sodium hydride (8.63 g, 0.36 mol of 60% dispersion in a mineral oil) was washed with toluene to remove mineral oil. To this 20 ml of dimethylformamide (DMF), 1-(but-1-enyl)pyrrolidin-2-one (25 g, 0.1798 mol) and a solution of methyl nicotinate (20.94 g, 0.152 mol) in 15 ml of DMF were added. The reaction mixture was heated at 90° C. for 2 hrs. DMF was partially removed under reduced pressure, 50 ml water added, further cooled to 0-10° C. and pH adjusted to 7 using HCl. The reaction mixture was extracted with ethyl acetate and dried over Na 2 SO 4 . After removing the solvent under reduced pressure a yellow solid was obtained, which on recrystallisation with diisopropyl ether gave 1-(but-1-enyl)-3-nicotinoyl-pyrrolidin-2-one (II, 35.1 g, 94% yield), 95% HPLC, M.R: 65-66° C. 1 H NMR (CDCl 3 ): δ 9.3 (1H, d), 8.8 (1H, d), 8.41 (1H, dt), 7.4 (1H, m), 6.76 (1H, d), 5.0 (1H, m), 4.5 (1H, m), 3.57-3.67 (2H, m), 2.7 (1H, m), 2.3 (1H, m), 2.0 (2H, m), and 1.0 (3H, t). 13 C-NMR (CDCl 3 ): δ 194.4, 167.1, 153.7, 150.4, 137.0, 134.4, 131.2, 123.3, 114.9, 51.7, 44.2, 23.2, 22.3, and 14.26. IR: 2966, 2937, 2855, 2847, 1631, 1613, 1489 Cm −1 . C. Preparation of Myosmine A mixture of 1-(but-1-enyl)-3-nicotinoylpyrrolidin-2-one (II), (40 g, 0.1639 mol), 50 ml water and 85 ml HCl were refluxed together for 12 hrs. The reaction mixture was cooled to room temperature, washed with 50 ml×2 ethyl acetate, further cooled to 0° C. and pH adjusted to >13 using NaOH. The reaction mixture was extracted with 100 ml×3 of dichloromethane and the extract dried over Na 2 SO 4 . After removing the solvent under reduced pressure, the crude solid obtained was purified by high vacuum distillation to give colorless solid myosmine (16.75 g, 70%). 1 H NMR (CDCl 3 ): δ 2.05 (2H, m), 2.94 (2H, t), 4.06 (2H, t), 7.34 (1H, dd), 8.18 (1H, dt), 8.64 (1H, dd), and 8.99 (1H, d). 13 C-NMR (CDCl 3 ): δ 170.56, 151.1, 149.1, 134.6, 130.0, 123.3, 61.5, 34.7, and 22.5. IR: 2961, 1620, and 1590 Cm −1 . D. Preparation of Nornicotine Myosmine (32 g, 0.219 mol) was dissolved in 150 ml of methanol and hydrogenated at atmospheric pressure with 1.3 g of 10% palladium on carbon as catalyst. After 5 hours the mixture was filtered and the filtrate was concentrated to get a brown solid (32 g, 94.9% purity by GC). It was further purified by vacuum distillation at 0.1 mm Hg to get pure nornicotine (27.46 g, 84.7% yield, 97.5% purity by GC). 1 H NMR (CDCl 3 ): δ 1.66-2.72 (2H, m), 3.0 (2H, m), 4.13 (1H, t), 7.24 (1H, m), 7.69 (1H, dt), 8.46 (1H, dd), and 8.59 (1H, d). 13 C-NMR (CDCl 3 ): δ 148.4, 148.1, 140.16, 134.1, 123.3, 60.0, 46.8, 34.2, and 25.4. IR: 3291, 2960, 1641, 1578 Cm −1 . E. Preparation of (R,S)-Nicotine To a solution of nornicotine (50 g 0.338 mol) in 100 ml water a mixture of 37% formaldehyde (49.7 g, 1.656 mol) and 85% formic acid (37.26 g 0.81 moles) was added and stirred at 85° C. for 20 hrs. The reaction was cooled and pH adjusted to >13 using NaOH, extracted with dichloromethane (100 ml×3) dried over Na 2 SO 4 and solvent removed completely to get crude oil (52.5 g, 94.33% purity by GC). It was further purified by high vacuum distillation at 0.1 mm Hg to obtain colorless (R,S)-nicotine (44.54 g, 81.3% yield, 99.1% purity by GC). 1 H NMR (CDCl 3 ): δ 1.72-2.0 (3H, m), 2.1 (3H, s), 2.25 (1H, m), 2.3 (1H, m), 3.08 (1H, m), 3.23 (1h, t), 7.25 (1H, m), 7.69 (1H, dt), and 8.5 (2H, m). 13 C-NMR (CDCl 3 ): 149.71, 148.76, 139, 134.97, 123.7, 68.9, 57.1, 40.5, 35.5, and 22.83. IR: 3233, 1642, and 1402 Cm −1 . Example-2 Preparation of Myosmine from I Sodium hydride (17.26 g, 072 mol of 60% dispersion in a mineral oil) was washed with toluene (25 ml×2) to remove mineral oil and added to 25 ml of DMF. To this a solution containing 1-(but-1-enyl)-pyrrolidin-2-one (I, 50 g, 0.3597 mol) and methyl nicotinate (41.8 g, 0.3057 mol) in 50 ml of DMF was added. The reaction mixture was heated to 90° C. for 2 hrs. DMF was partially removed under reduced pressure and 100 ml water and HCl (165 ml) were added. The reaction mixture was heated to 110° C. for 12 hr, cooled and washed with ethyl acetate (50 ml×2). The aqueous layer was cooled to 0° C., pH adjusted to about 14 using NaOH, extracted with dichloromethane (100 ml×4), the extract dried over Na 2 SO 4 , the solvent removed completely and the crude solid was purified by high vacuum distillation to get myosmine (34.38 g, 77.2% yield, 98.5% purity by GC).

A process for (R,S)-nicotine is described. Condensation of 1-(but-1-enyl)pyrrolidin-2-one with nicotinic acid ester gave 1-(but-1-enyl)-3-nicotinoylpyrrolidin-2-one which on treatment with an acid and a base gave myosmine. Myosmine was converted to (R,S)-nicotine by reduction followed by N-methylation.

CROSS-REFERENCES TO RELATED APPLICATIONS [0001] This application is a submission to enter the national stage under 35 U.S.C. 371 for international application number PCT/EP2003/050349 having international filing date Jul. 29, 2003. STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT [0002] (Not Applicable) REFERENCE TO AN APPENDIX [0003] (Not Applicable) BACKGROUND OF THE INVENTION [0004] 1. Field Of The Invention [0005] The invention relates to a computer network for the configuration, installation, monitoring, error diagnosis and/or error analysis of plural technical-physical processes. These may be in particular electrical drive processes which run under control, regulation and/or monitoring by plural process computer nodes (in the example of an electric drive system: drive regulator). The process computer nodes are connected to at least one diagnosis computer node via a shared communication system. In the diagnosis computer node, one or more configuration, monitoring and diagnosis services or functions is/are implemented, which are allocated to the processes and/or the process computer nodes and/or to the data processing operations running therein. [0006] The invention further relates to a diagnosis computer node for the said network. This is formed as a server with interfaces for at least one database and for communication with at least the process computer nodes and with other client computer nodes. The invention further relates to a communication computer node or a communication module, the latter being formed as a software and/or firmware module, which is respectively suitable for use in the said network. [0007] 2. Description Of The Related Art [0008] From a conference volume to accompany the congress “SPS IPC Drives”, which took place in Nürnberg in November 2001, the technical article “Info-Portal für anlagenübergreifende Prozessvisualisierung und-management via Internet” (authors: Andreas Kitzler und Werner Felten) was disclosed. This proposed a communication structure in which plural, mutually independent automation systems, cells or appliances may be combined, monitored, visualised and the like via an information port. At the information port, access can be gained to the Internet. The communication between the automation cells (known as Supervisory Control and Data Acquisition—SCADA) on the one hand and the central web server of the information port on the other is effected via standard interfaces on the basis of the extensible mark-up language XML. To this end, each automation system is provided with what is known as an XML-agent for communication with the information port on the basis of TCP-IP. Thus management should be able to evaluate in a qualified manner various automation cells or SCADA systems via the web. However, the individual sensor data have to be collected on the level specific to them, prepared there and made available to the information port via the XML agent before they can be transported from the information port via the web. [0009] From DE 196 14 748 (A1-published and unexamined specification, and C2-patent specification), an error diagnosis system is known in which a diagnosis computer node communicates via plural bus systems also on the basis of the communication protocol TCP/IP (Transport Control Protocol/Interface Program) with control station computer, control process computer and field process computers. For communication between the field process computers on the one hand and the diagnosis computer node on the other, a serial field bus according to the standard RS485 is used, wherein the diagnosis computer node dominates the serial field bus (RS485) according to the master/slave principle. The bandwidth for the data transmission (RS485 interfaces) is not sufficient with the increasing data inundation. The data to be presented on the user interface cannot be transmitted quickly enough due to the ring communication structure within a field process computer cluster. It takes about 50-60 ms to scan one parameter—in appliances with about 500 drives, for example, any error occurring would only be notified after more than a minute. Each parameter is transmitted individually, and the transmission of software packages is not possible. BRIEF SUMMARY OF THE INVENTION [0010] The object of the present invention is to develop a hardware and in particular software tool for the diagnosis of complex technical appliances and systems which is tailored to the requirements and needs of the user and in particular meets the following requirements: [0011] Versatile functions for monitoring and diagnosing large drive systems: [0012] The object of the invention is to develop a hardware and in particular software tool for monitoring and diagnosing in particular large drive systems. The diagnosis system is intended to offer comprehensive, versatile functions which are tailored to the currently very different needs of the various user groups of the client. [0013] (2) Easy-to-use, transparent user interfaces: [0014] The user interface of the diagnosis system is the only part of the software with which the client comes into contact. In this sense it is the “bulletin board” of the software and is critical for acceptance and judgment thereof by the client. In planning the user interface, this should be so contrived that it is easy to use even by not very highly trained staff. The large number of data to be indicated in the diagnosis of large appliances must be graphically prepared and presented in an ergonomic diagram to the user. [0015] (3) Shortening of the time necessary to detect a possible error: [0016] The usefulness of the diagnosis system to the client will be that he is presented with data necessary for detecting and correcting the error immediately after an error has occurred. Thus the time can be reduced during which the appliance is not productive. [0017] (4) Situation-dependent presentation of diagnosis data [0018] The diagnosis system should make available the right data at the right time at the right place: [0019] Preparation of the diagnosis information according to the requirements of the respective user circle (e.g. appliance operator, technician, installer)(→the right information) [0020] Indication close to the time of diagnosis data directly after an error has occurred (→at the right time) [0021] Access to THE DIAGNOSIS SYSTEM by any PCs of the client without installation cost—both in the local client network and via remote access (→at the right place). [0022] (5) Reduction of critical appliance states by prophylactic maintenance and constant monitoring of the appliance: [0023] In future, the diagnosis system is to contain mechanisms which help to detect possible oncoming failure of appliances and to inform the client. Thus the reliability of the drive system can be further increased. [0024] (6) Comprehensive diagnosis/measuring operations via rapid Ethernet interfaces, including the Ethernet overall concept of the machine in order for example to measure, record and evaluate a reference signal of a real leading axle. [0025] (7) Prophylactic diagnosis (e.g. transmitter failure likely in . . . days). [0026] (8) An “expert system” is intended to ensure error localisation within 10 minutes maximum and simplify error correction substantially. [0027] (9) Web browser functions. [0028] (10) The diagnosis system must be able to run on plural platforms (e.g. diverse control stations). [0029] (11) Integrated data protocolling/analysis (register values, commands) must be available without additional hardware (data analyser). [0030] (12) Cyclical data protocolling at a central database server. [0031] (13) Access option for the machine manufacturer to drive systems supplied via remote diagnosis. [0032] (14) Operator guidance and parameter handling (configuration, installation, error search, software updates) are to be substantially improved. [0033] (15) Development of branch-overlapping solutions [0034] In spite of taking clients' wishes into account, the diagnosis system for branch-overlapping use is to be developed so that use in other branches (e.g. machine tools, textile machines) is possible without great complication/expense. [0035] (16) Preparation of software tools for the installation of drive systems with in future up to 500 axles [0036] Drive systems with more than 300 axles can only be installed without software support with excessively high cost. To this end, with the diagnosis system according to the invention a suitable software tool is to be developed. [0037] (17) Shortening of the installation time and reduction of the installation costs: [0038] By means of the diagnosis system, the costs of installation are to be reduced in the long term by the delivery of suitable software-supported methods. [0039] (18) Worldwide access to the technical-physical processes of the appliance, in particular drive systems, for rapid, economical diagnosis: [0040] For rapid and reliable service and for appliance diagnosis, worldwide access to the drive system will be possible. [0041] On the other hand, in order to prevent the disadvantages from the prior art from arising in the computer network having the features mentioned in the introduction, it is proposed according to the invention that the shared communication system between the process computer node and the diagnosis computer node is realised with the Ethernet or another bus or communication system operating asynchronously and/or with a stochastic access method. An access method of this type is known for example under the abbreviation “CSMA/CD” (Carrier Sense Multiple Access/with Collision Detection). This industrial Ethernet use for realising a communication infrastructure permits a higher bandwidth for data transmission compared to the prior communication via RS485 and the associated USS protocol, so that larger quantities of data can be transmitted from the process computer node to the diagnosis computer node. There is an increasing need for this, due to the increasing complexity of the technical appliances with an increasing number of process computer nodes and associated technical-physical processes. Furthermore, the Ethernet has proved a substantial standard in offices for transmitting large quantities of data. By the use according to the invention of the Ethernet with the protocol TCP/IP also known per se, the path is cleared for the diagnosis system according to the invention to be compatible with and/or combined with the Internet. Thus the advantage is gained that diagnosis data can be sent via the Internet. In addition, a technical appliance can be monitored with a large number of processes from any client node, in particular via the Internet. [0042] In order to be able to process the extensive quantities of data arising in a practical manner, a decentralised diagnosis together with pre-processing is advantageous. It is also practical to move extensive diagnosis functions as close as possible to the technical-physical process or apparatus concerned. In this respect, according to an advantageous embodiment of the invention, a communication unit or computer node is interposed between the Ethernet or the other bus or communication system and at least one of the process computer nodes, thus connecting the respective process computer node to the Internet or other bus or communication system. The communication computer node or communication unit can additionally also undertake event- and/or enquiry-based communication to the diagnosis computer node. [0043] In particular, when in a further configuration of the invention the communication unit or the communication computer node is so formed that it communicates via XML protocol and/or as an XML-based interface (XML—Extensible Markup Language) with the diagnosis computer node, in projecting and configuring the technical appliance to be monitored thereby, it is possible to react very flexibly and with relatively low cost to technical requirements and client wishes. On the basis of the invention, a standardised, versatile network-computer structure can be created, which can be easily extended by further functions. Particularly, with the use of XML protocol and/or XML-based interfaces, the diagnosis data can be so prepared from the process computer node and/or communication node for the diagnosis computer node that these data can be transmitted easily via the Internet from the diagnosis computer node to client computer nodes. [0044] In order to be able to manage the extensive quantities of data in a practical manner via decentralised pre-processing, according to one embodiment of the invention it is provided that the communication unit or communication computer node is provided with functionalities for error search or diagnosis in the region of at least one of the process computer nodes or of a technical-physical process. With this notion, extensive diagnosis functions can be located close to the components concerned. [0045] The Internet-compatibility of the diagnosis system according to the invention is enhanced if according to an embodiment of the invention the diagnosis computer node is formed to make available or at least support web-based user interfaces for client computer nodes. This can be effected via data remote transmission and/or a long-distance traffic network (e.g. Internet). It is further within the scope of the invention if in addition the diagnosis computer node is provided with function components which support the education of the user interfaces in the client computer node. [0046] It is problematic whether the user at a client computer node must confident that the client user interface is reproducing (diagnosis) data and information which are still substantially up-to-date or close in time. Any failure of the diagnosis server should be detectable, and furthermore errors and other events in the technical-physical process and/or process computer node are to be capable of being communicated to the user close to time via the user interface of the client computer node allocated to him. [0047] To solve this set of problems, within the scope of the general inventive notion, a diagnosis computer node having the following features is proposed for use as a server in the network outlined above: The diagnosis computer node is set up to operate as a server and has interfaces to at least one database, for communication with the communication and/or process computer node and for communication with other client computer nodes; The one or more interfaces to the other client computer nodes are realised by using a Servlet container (known per se), which transmits diagnosis data to the client nodes; These diagnosis data are obtainable from the interfaces for communicating with the communications and/or process computer node; The one or more above-mentioned interfaces which are allocated to the communication and/or process computer nodes are realised on the basis of the Ethernet; A diagnosis channel is formed, which comprises one or more Ethernet interfaces, which are allocated to the communication and/or process computer nodes; The diagnosis channel further comprises an event management unit, which can access the database and can process diagnosis data obtained at the Ethernet interfaces; Further, the diagnosis channel comprises an event monitoring unit, which is formed on the basis of the Servlet container and makes available output data from the event management unit to one or more Applets on external client computer nodes. [0055] It is thus possible to transmit data, in particular diagnosis data in cycles between the diagnosis computer node and the user interface of a client computer node. Thus a user at the client computer node can be informed close to time of events arising in the region of the process computer node and/or of the technical-physical processes. Thus a wide variety of appliance information can be made available on the user interface of the client computer node in a comfortable manner. The data transmission can be carried out particularly advantageously with Java technologies, in particular a Java Servlet on the diagnosis computer node as a server and a Java-Applet in the client computer node. Thus it is also possible to make available diagnosis information in the form of websites to a user on the client computer node. In this case, the use of Java-Applets offers very versatile representation options, which are easily extensible by bought-in Applets with graphical capabilities. [0056] The solution to the above set of problems is assisted by the diagnosis channel according to the invention in the diagnosis server, by means of which a cyclic communication can be effected, wherein data packages are regularly exchanged. If a data package is missing, it can be detected in the client computer node that an error has occurred (“event+heartbeat”). The heartbeat corresponds as it were to the dead-man's button known in particular in the field of railway safety technology. By means of the diagnosis channel, therefore, a display of diagnosis data originating from the process computer node can as it were be triggered via diagnosis server or diagnosis computer node to the client computer node on his user interface. The representation of the error on the user interface is no longer dependent on an enquiry being sent to the diagnosis server by the client computer node due to the diagnosis channel according to the invention. Rather, the process computer nodes, optionally via individually allocated communication nodes, can itself indicate as it were new events, in particular errors. This mechanism is substantially supported by the diagnosis channel in the diagnosis computer node in that diagnosis or error data notified via the event monitoring unit by the process computer node are forwarded to the user interface of the client computer node for a user at that interface. [0057] According to a particular configuration, the interfaces in the diagnosis computer node are contrived for communication with the communication and/or process computer nodes by means of XML protocols. Thus proprietary solutions which have restricted applicability are avoided. [0058] In the diagnosis computer node, all diagnosis data are intended to be made available to the user interfaces on the client computer nodes in a web-based manner. It has turned out to be particularly advantageous for this purpose to have a combination of the web-server Appache with the Servlet-engine “Tomcat”. [0059] In the diagnosis computer node according to the invention and indicated above, the diagnosis channel ensures in the case of an event, in particular error, to prompt a reaction from the client computer node thereto with his user interface. If an error or event occurs, corresponding diagnosis data are picked up at the Ethernet interface of the diagnosis channel, and are allocated to the communication units, communication and/or process computer nodes. The event management unit can access the diagnosis or event data in the form of a telegram for example at the Ethernet interface. The event or diagnosis data are processed and a corresponding datum is written into the database. The output data from the event management unit pass to the event monitoring unit applied in the Servlet container. In the example of the Intranet, this event monitoring unit transmits at its output a datum advantageously direct to the client computer node, without the interposition of a web server. The datum contains a prompt to demand representative diagnosis data from the diagnosis server due to events or errors. Thus the need for constant polling throughout the period of operation, which would require increased data transmission capacities, is avoided. [0060] To connect the process computer node to the Ethernet or another asynchronously operating communication system with the diagnosis computer node, and in particular to create the option of an event-based communication between process computer nodes and diagnosis computer nodes, extensive diagnosis functions being located as close as possible to the technical-physical process, in the scope of the general inventive notion, a communication computer node or a communication unit are proposed as a software and/or firmware module, which is suitable for use in the computer network outlined above and is distinguished by the following features: The communication computer node or the communication unit has a first interface which is allocated to the at least one diagnosis computer node; This interface is programmed or formed for communication via protocols of the TCP/IP family, including UDP/IP, preferably on the basis of the Ethernet; The communication computer node or the communication unit has one or more second interfaces which is/are allocated to one or more process computer nodes; The first and one or more second interfaces may be coupled together via one or more information brokers; The one or more information brokers are respectively set up in terms of program and/or circuit technology as sub-units for bidirectional, enquiry- and/or event-based data communication, which takes place between the first and the one or more second interfaces. [0066] The purpose of the communication unit or communication computer node is to roll out all communication tasks between the process computer node and its outside world. This includes for example access to parameters of the process computer node, e.g. of the drive regulator, the down- and up-load of regulator firmware for example and associated data records, as well as the delivery of diagnosis functionalities. [0067] With respect to the realisation of hardware of the communication node according to the invention, it might be advantageous to manufacture a free-standing structural unit with the communication functions incorporated therein and to mount this on the printed circuit board for the process computer node. Alternatively, the communication node hardware may be incorporated wholly or in part in the circuit on the printed circuit board of the process computer node and/or on that of the diagnosis computer node. Alternatively, it is within the scope of the invention to realise the communication node as a “PC” as it were with its own housing, which can be snap-fitted on to a rail-type mount for the process computer node. [0068] As an operating system for the communication node according to the invention (communication unit or communication computer node), the use of Linux has been found advantageous. In addition, C++ is suitable as a sufficiently versatile and powerful programming language. [0069] With the concept according to the invention of the communication node between the process computer and diagnosis computer, there is the option for transmitting data to the outside world via XML-based protocols (instead of proprietary protocols). With the mark-up language XML, which is widespread and known per se, for Internet applications in combination with the delivery of platform-independent XML parsers, there is the further option of simply exchanging data in heterogeneous system environments. By way of validation mechanisms (XML models) that are already available, the structure and admissible content of a telegram can be established simply, and testing for quality takes place automatically. As a character-based protocol, an XML-based telegram is easy to generate and if necessary to process by hand or by simple scripts. [0070] In order to be able to implement the most extensive diagnosis functions as close as possible to the technical-physical process, according to an advantageous embodiment of the invention it is proposed that the one or more information brokers comprise function components which are formed to perform an error search or diagnosis in the region of the process computer node and/or technical-physical processes. In particular in this connection, a further advantageous embodiment of the invention involves the installation of interpreters for the loadability of scripts known per se on the communication computer node or unit, which interpreters are formed for access to function elements or functionalities in the information broker(s) for the purpose of carrying out monitoring and diagnosis functions. One advantage achievable thereby consists in the more effective error search: by means of the scripts in combination with the language PERL, in a relatively simple manner, efficient error search conditions can be installed or loaded by the diagnosis computer node on the communication node. Thus the functionality available on the communication node can be extended once again. [0071] It is within the scope of the invention that the communication unit or the communication computer node in certain cases operates as a server with respect to the diagnosis computer node (as client) if on the part of the diagnosis computer node requirements are present at information services, which are to be realised for example by information brokers in the communication node. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS [0072] Further details, features, advantages and effects on the basis of the invention will appear from the following description of preferred embodiments of the invention and from the drawings given by way of example. The drawings show: [0073] FIG. 1 a schematic appliance diagram of the diagnosis system according to the invention with local and worldwide access to diagnosis data; [0074] FIG. 2 a schematic block diagram of an example of a communication system of an electric drive system provided with the diagnosis system according to the invention; [0075] FIG. 3 shown in schematic block representation, the basic structure of the diagnosis system according to the invention; [0076] FIG. 4 a detailed block diagram of the internal structure of the diagnosis computer node; [0077] FIG. 5 a similar block diagram of the internal structure of the communication computer node; [0078] FIG. 6 a user interface, by way of example, on a client computer node for an appliance-based appliance image with the example of a printing press, generated by means of a Java-Applet in combination with a corresponding Servlet on the diagnosis computer node; [0079] FIG. 7 a further, similarly generated user interface via a drive-system-based appliance image with the example of a printing press. [0080] In describing the preferred embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific term so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the word connected or term similar thereto are often used. They are not limited to direct connection, but include connection through other circuit elements where such connection is recognized as being equivalent by those skilled in the art. In addition, many circuits are illustrated which are of a type which perform well known operations on electronic signals. Those skilled in the art will recognize that there are many, and in the future may be additional, alternative circuits which are recognized as equivalent because they provide the same operations on the signals. DETAILED DESCRIPTION OF THE INVENTION [0081] According to FIG. 1 , an electric drive system for a large number of axles 1 to be driven synchronously with one another, e.g. of a printing press provided with a large number of electric motors 2 , each driving one axle 1 . The electric motors 2 are each triggered or regulated via respective converters 3 with upstream process computer nodes 4 , realised in the present printing press drive system as drive regulators. To communicate with a diagnosis computer node, respective communication computer nodes 5 are connected upstream of the process computer nodes. The converter 3 , the process computer node 4 and the communication computer node 5 can be incorporated structurally into a common assembly, as is shown in the drawing, which is housed in a respective switch cabinet 6 . [0082] According to FIG. 1 , the diagnosis computer node can also communicate with a control station, plural client computer nodes for diagnosis and via an Internet router or ISDN or in an analogue manner via the Internet with one or more geographically remote client computer nodes for remote diagnosis. Thus the diagnosis data prepared at the respective drive process of the electric motors 2 by means of the process computer node 4 and/or of the communications computer node 5 may be retrieved via the diagnosis computer node both locally and from any other location. [0083] According to FIG. 2 , the individual process computer nodes 4 are connected together in the context of a ring structure for synchronised communication, in which case one of the process computer nodes 4 (the one printed darker in each case in FIG. 2 ) always operates as the communication master. This simultaneously has an interface for asynchronous communication via the Ethernet with plural control computer nodes SPS. In order also to support cross-communication between individual rings with process computer nodes 4 , a multi-link controller MLC is also introduced as a structural element (known per se from U.S. 2003/0100961 A1). [0084] In the reference plane, (diagnosis) data are constantly being required from the plane of the process computer node 4 . These are essentially system data such as status and error messages, maintenance data and records for quality control. In order to evaluate the data, a diagnosis computer node is available in the reference plane as is shown in FIG. 2 . In this case also, the Ethernet known per se is also made available as a communication medium both with the individual process computer nodes 4 and also with the diagnosis stations in the reference plane, which may form client computer nodes with the user interfaces. The OSI layer model known per se permits complex communication mechanisms between the process computer plane and reference plane. Since the diagnosis is to be effected independently of the remaining communication, each process computer node 4 is reachable via the Ethernet by the diagnosis computer node (and vice versa). Thus, inter alia, the advantage is gained that communication problems in the synchronised ring bus of the process computer node can be mutually detected. [0085] Definition of important terms: [0086] Event An event is a datum which is sent by a drive regulator (process computer node at the technical-physical process) upon occurring at the diagnosis server (diagnosis computer node). It appears in the event display of the user interface and in the logbook. Events are for example error messages, messages about the start/stop of records, maintenance messages etc. Every event has an unambiguous event identification via which an event description can be retrieved in the documentation. [0087] Record With a record, any parameter curves can be picked up by any regulator and stored in a database. [0088] Monitoring view The monitoring view is a graphic representation of one or more parameters of one or more regulators. It serves to monitor the values curve of these parameters for deviations from the norm (e.g. monitoring of the motor temperature). [0089] Parameter list The parameter list contains all parameters available to one type of regulator. [0090] Long-term record A record whose data are stored on the diagnosis server in a database. Opposite to ring memory record. [0091] Ring Memory [0092] record A record whose data are stored in a ring memory of the process computer node. Only upon completion of the record can the data be stored on the diagnosis server. [0093] Configuration [0094] Wizard A sequence of individual pages on which the user can make settings. Each step in the configuration comprises a number of functions and is shown on one page. According to what the user does in the previous step, a corresponding consecutive page is displayed (e.g. in the configuration of the record: option in step 1: ring memory or long-term record: according to the selection, the user receives pages displayed for configuring the ring memory or the long-term record). [0095] FIG. 3 gives an overview of the basic structure of the diagnosis system. The user has various web-based user interfaces available, which present him with the functionality of the diagnosis system in a manner suited to him. For operation of the system, it is unimportant whether the user is local to the appliance or at another location. [0096] The functions desired by the user are forwarded by the user interfaces to the diagnosis computer node. Here, every functionality which is available in the interface is implemented. Further, the diagnosis computer node undertakes to store all the data occurring in the database DB. All data specific to the appliance such as for example the appliance configuration or component databases, all data specific to diagnosis such as e.g. long-term records or ring memory records and all data relating to application, are managed in the database. [0097] If relevant data are made available for diagnosis by the control or control station e.g. of a printing press, these can be further processed by special components incorporated in the diagnosis computer node. [0098] The tasks incoming from the user interface at the diagnosis computer node are processed there and converted into commands that will be understood by the corresponding regulator. The communication between diagnosis computer nodes and communication computer nodes with a connected regulator is effected via Ethernet and XML protocols supported thereon. At the communication computer node, the tasks received from the application server are carried out and the result is sent back to the diagnosis computer node. [0099] Each of the supported process computer nodes, e.g. regulators, must offer an XML-based interface in order to permit the diagnosis computer node access to the required data. This can be effected e.g. by means of a communication computer node (“communication PC”), which is either incorporated in the process computer node (e.g. b maXX 4600) or is added to the process computer node as a plug-in card. Alternatively, the XML-based interface of the process computer node can also run without communication PC hardware as part of the diagnosis computer node. The communication between the interface units on the diagnosis computer node and the process computer node hardware is then carried out via proprietary protocols and RS232 or Ethernet. [0100] The requirements mentioned in the introduction require a component-based, distributed architecture of the diagnosis system. According to the general principles of software development, data capture, data processing and data storage and the user interfaces are in modular form and are separate from one another. Thus a transparent and more calibratable structure is achieved, which can be easily extended by further functionalities. It can thus be ensured that the diagnosis system grows along with the increasing number of drives (calibratability). By the use of Ethernet and TCP/IP for the communication between the communication PCs, the diagnosis computer node and the applications, there is a substantially larger bandwidth available for data transmission. This results in a substantially faster diagnosis system than that of DE 196 14 748 mentioned in the introduction. [0101] Further, the component-based structure simplifies coverage of the large function scope of the diagnosis system. For every user group, an user interface tailored to their individual needs can be developed, which has access to the underlying infrastructure (diagnosis computer node). [0102] By separating user interface and implementation of the functionality in the diagnosis computer node, new applications can be developed in future with less expense. By using modem software technologies, the Internet can be used as a communication medium that is available and accepted worldwide. Thus it is not important whether monitoring of the appliance is carried out locally on site or from another site, e.g. the service department. By using current Internet browsers for the user interfaces, the installation costs for the user are substantially reduced and the number of hurdles for the user in using the diagnosis system is significantly reduced. [0103] The component-based architecture furthermore permits the support of newly developed methods of monitoring and diagnosing drives in that new functions are incorporated as components in the diagnosis computer node. [0104] Substantial advantages of the diagnosis system according to the invention consist in particular in the following: [0105] The client has universal access by the web interface to the diagnosis functions: The right information close to time at the right place Simple user interface by way of web browsers User guidance simplifies operation and configuration The web interface is platform-independent Operation possible via the Internet if desired. [0111] (2) The client receives data concerning the state of the appliance which have been prepared for him: Data preparation in the form of graphic representations Prophylactic diagnosis. [0114] (3) The substantially extended diagnosis options permit: Extended monitoring of the appliance Simpler localisation of the cause in the case of an error. [0117] (4) The functions for installation support permit: Faster installation→reduction in costs Improved quality of installation by specified and documented acceptance protocols. [0120] A function group “software update” permits the installation or updating of a firmware of the process computer node e.g. to firmware. All actions carried out in this function group are detected in a log file. It is a precondition for installation or updating of the firmware that the regulators selected have unambiguous regulator identification. The following actions must be possible: [0121] Selecting drives [0122] The user selects the drives to be updated from a drive list. [0123] 2. Selecting firmware [0124] The user selects the firmware which is to be loaded on to the drives to be updated. [0125] 3. Carrying out the software update [0126] After the display of a warning notice, the software update is carried out. [0127] A function group “configure events” offers the option of recording any events in the events display and in the logbook. The event broker present in the communication PC of the respective process computer node is configured by means of the functions mentioned below, so that it monitors the desired parameter combinations for occurrence of the configured event. If the event does occur, it is sent to the diagnosis computer node and is displayed there in the event display. The following actions may be possible for example: [0128] Selecting drives [0129] The user selects the drive for which an event is to be configured or deleted. [0130] 2. Configuring event [0131] The user configures an event by means of a configuration wizard [0132] 3. Deleting event [0133] The user deletes an event from a list with current events. Events which are present as standard, e.g. errors, cannot be deleted. [0134] 4. Sending event configuration to drive [0135] The user sends the configured event to a drive selection and activates the same. [0136] A function group “scripts” offers the option of carrying out complex diagnosis functions. In order to make complex enquiries of parameters, PERL scripts can be written which are sent to the corresponding communication PC and are executed there. The following actions are to be possible: [0137] Loading of the script on to the server [0138] The user loads the script from the communication PC of a drive on to the server. [0139] 2. Loading of the script to the drive [0140] The user loads a script selected from a list on to a selected drive. [0141] 3. Editing script [0142] The user edits a script. [0143] 4. Execution of the script on the communication PC [0144] The user starts the script on a drive. [0145] Below, an overview of the architecture of the diagnosis computer node of the diagnosis system is given. FIG. 1 shows a detailed structure of the diagnosis system. It consists substantially of three planes: [0146] Client computer node with user interfaces [0147] All functionalities of the diagnosis system can be operated via the user interfaces. For the user of the diagnosis system it should make no difference whether he is at the appliance in the local network or is connected to the application server via the Internet or a telephone dial-up connection. [0148] Diagnosis computer node [0149] This is the core of the whole application. Its functionality is divided into various components (managers). Each manager is self-contained and makes available its functionality to the web-based user interface or to other server components. All data necessary for the function of the manager are stored in the connected database. In order to ensure encapsulation and consistency of these data, access is only permitted to these databases via the functions made available by the manager. This also ensures that a change in the database structure of one manager does not automatically lead to changes at other managers. [0150] In order to make available the functionalities of the managers to the user interfaces, a suitable infrastructure must be created (Tomcat Servlet container). For communication with the web interface for installation, monitoring and diagnosis, an Apache web server is to be used. This makes available HTML pages in which Java Applets are embedded. The data to be displayed on the interface is transmitted by means of SOAP (Simple Object Application-Protocol) to the appropriate units. The user interface retrieves e.g. a function of the appliance manager. The parameters to be transferred and the reference of the function are sent to the Intra- or Internet by means of the SOAP protocol. In order to ensure the transparency of current firewalls, the function retrieval is sent in the form of an HTTP telegram. A web server on the site of the application server receives the HTTP telegrams with the SOAP content and forwards them to the SOAP handler. The SOAP handler in the Tomcat Servlet container decodes the enquiry and retrieves the desired function from the appliance manager. The function is executed and the return values are in turn converted into the SOAP protocol and sent to the interface as an HTTP telegram. [0151] An essential property of a diagnosis and monitoring system is that the user is informed close to time of events occurring at the appliance. This presents a problem for the architecture described above, since both for communication via SOAP and for the HTML pages, there is no event-based reporting. As a remedy, events occurring at the appliance, e.g. the occurrence of an error or the update of a parameter value in one interface, must be communicated via an event channel to the user interfaces or constantly polled. [0152] Process computer node [0153] The process computer node plane makes available to the diagnosis computer node the data from the process computer node. The process computer node must be connected. As already indicated, the diagnosis computer node consists of various encapsulated server components (managers) which make their functionalities available via the Tomcat Servlet container to the user interface or client computer node. The component-based structure is intended to ensure that the function scope of the diagnosis system can be extended. The managers are realised as Java components. The individual managers are described below. [0154] The appliance manager contains all the necessary data about the configuration of the appliance. This contains data concerning the components present in the appliance, the grouping of components, addresses, etc. Functionalities are to be made available which permit the appliance configuration to be represented in the form of various overview images. Furthermore, all documentations are to be made available to the data contained in the appliance. [0155] In planning the appliance manager, it should be ensured that by means of the functionalities of this component any appliances can be described in the field of drive technology. [0156] The event manager administers all events occurring in the diagnosis system such as e.g. error messages or maintenance events. It gathers all events that have occurred in the form of logbooks and makes them available to the user in a configurable representation. Further, the event manager has functions by means of which any event monitoring can be defined which is then configured by the event manager on the corresponding regulators. [0157] The record manager makes available functions by means of which any parameters from any regulators can be recorded. It offers various types of record which can be configured by the user. All data occurring in a record are stored by the record manager in a database and if required made available to other units, e.g. a graphics unit of the interface. [0158] All functionalities in the diagnosis system are protected against unauthorised access. Every user has a user identity and belongs to a user group which allows him a rights profile for access to the functionalities of the manager. These data are configured and stored in the user manager. Every function in the managers has an unambiguous identification. If a user wants access to a function, first the user manager is asked whether the user has the appropriate rights to carry out this function. The database in which the user data are stored is to be password-protected against unauthorised access. [0159] The logging manager gathers all logging data from the connected regulators and stores their log and debug messages in a database or in rolling log files. [0160] The communication computer node or communication PC according to FIG. 5 carries out communication tasks between the process computer node and the outside world. The software structure for communication with the process computer node is described below. [0161] Each appliance that is to communicate with the process computer node must respond thereto via a suitable software interface on the communication PC. By means of the communication PC, almost any software interface based on the Ethernet or a serial interface can be realised. The software architecture on the communication PC is described below. Classification into the overall concept can be deduced from the comments above. FIG. 5 shows the software structure on the communication PC or the process computer node. [0162] Any functionality which is to be made available by the process computer node is realised in a software module (information broker or manager). For example, the information broker makes “parameters” available to a parameter interface via which any parameter of the process computer node can be read and written. The information broker “errors and events” presents any events and errors to the outside. The two information brokers “parameter demand data” and “cyclical setpoint values” carry out communication with the control. They are only available on the regulators which form the master in the sercos ring and thus must communicate with the control. The information broker “software download” delivers functions for automatic up- and download of the regulator firmware. A parameter manager (not shown) acts as internal management of the regulator parameters on the flashcard. It is not relevant to the communication with the outside world. [0163] The communication of the information brokers “parameters”, “error and event” and “software download” with the outside world is effected via XML-based protocols. All enquiries or responses are transmitted in XML messages defined by means of an XML model. [0164] Each of the available brokers can process more than one enquiry at a time from one or more clients. Essentially, the communication PC of the process computer node communicates with the control and the diagnosis computer node. In communication with an SPS control, it must be ensured that the messages are processed in each case without an unnecessary time lag at a process of the process computer node, as these are of substantial significance for operation of the appliance. Since the enquiries can only be processed sequentially on the processor of the process computer node, it must be possible to process enquiries from the SPS control in strict precedence. This should be ensured by allocating priorities for the enquiries. Each enquiry to one of the brokers on the communication PC is provided with a priority. According to this priority the enquiry is preferred or treated as subordinate. [0165] In addition to the information brokers, there are further, in part optional, software modules on the communication PC: A logging server receives log and debug messages from the information brokers and makes them available to the outside world. A web server offers a simple web interface for operation and configuration. An FTP server gives simple up- and download of firmware on to the process computer node. A client for time synchronisation supplies a matching time to all communication PCs of an appliance. By means of a PERL interpreter, any scripts can be carried out with diagnosis or control functionalities. The configuration manager carries out starting of important services (e.g. automatic configuration of event monitoring for an error in the technical- physical process) and management of the configuration data of the individual software modules. A Telnet access is available for maintenance purposes. [0173] The software modules of the communication PCs are described below. [0174] The object of the information broker “parameters” is to prepare XML-based parameter interface for access to the parameters of the process computer node. As protocol, an XML-based protocol defined by means of an XML model is used, which communicates via TCP/IP with the client. From the viewpoint of the client, the following functions should be available: [0175] Reading of parameters [0176] The information broker “parameters” should be able to read a group of any parameters from the processor of the process computer node. In this case, in addition to once-only reading, the cyclical reading of parameters should be possible. The client is to be able to set the interval between reading operations and the number of reading operations. [0177] Writing of parameters [0178] The information broker “parameters” should be able to write a group of any parameters on to the process computer node. [0179] The task of the information broker “errors and events” is to prepare an XML/based interface, via which a client is informed of events occurring at the regulator, without constantly having to enquire of the regulator. As a protocol, an XML-based protocol defined by means of an XML model is used, which communicates with the client via TCP/IP. From the viewpoint of the client, the following functions are to be available: [0180] Configuration of event monitoring [0181] At the information broker “event”, it will be possible to specify any entry conditions for an event, upon the occurrence of which a message is sent to the client. If the event has occurred, in addition to the parameters taking part in the entry condition, it will be possible to scan further parameters from the regulator. [0182] An accepted task will be confirmed by the broker. [0183] The information broker “event” will have extensive functionalities which offer the client wide-reaching possibilities of forming entry conditions. An entry condition will be composed of plural parts, which can be linked together logically by AND or OR. Within each partial condition, the value of the parameter currently scanned can be compared either to a comparative value sent within the configuration message or to the most recently read parameter value. Optionally, a tolerance limit can be taken into account, which is settled with the comparative value. For the comparison, both all logical operators (<,>,<=, >=, |=) and the comparison to a bit mask are to be carried out. In addition, for each partial condition, a trigger mode is to be taken into account which indicates whether the event is to be sent the first time the event condition is encountered, upon disappearance of a condition already encountered, or in both cases. [0184] Notification of an event [0185] When the configured event condition is encountered, an XML message is to be sent to the client. [0186] Ending of event monitoring [0187] By means of an XML message provided for this purpose, event monitoring in progress can be ended. [0188] Enquiry of the status of event monitoring [0189] By means of an XML message provided for this purpose, the client can enquire of the information broker “event” whether event monitoring is in progress or has already finished. [0190] A difference from the information broker “parameters” is that there is no permanent socket connection to the client. After the configuration of the event, this is dismantled and only if the configured event arises is it re-assembled. To this end, on the part of the client a corresponding server port must be available. [0191] The information broker “cyclical setpoint values” effects part of the communication with the control. It is used in particular with printing press applications provided there is a process computer node or regulator which is a sercos master in a drive ring. [0192] The task of the information broker “cyclical setpoint values” is to supply the regulator at regular time intervals with new setpoint values from the control. In this case, it receives telegrams sent from the control and forwards them to the regulator. It should have the following capabilities: [0193] Receiving of setpoint value telegrams from one or more controls [0194] The information broker “cyclical setpoint values” will be capable of receiving setpoint value telegrams from one or more controls. The communication with the control may run via a proprietary protocol and/or the protocol UDP/IP. [0195] Forwarding of setpoint values to the regulator [0196] All setpoint value telegrams received by a control SPS will be forwarded with the highest priority to the process computer control or regulator. [0197] Monitoring of the setpoint value telegrams [0198] For diagnosis purposes, it will be possible to forward the incoming telegrams from the control both to the regulator and additionally to the diagnosis system. [0199] The information broker “parameter demand data” effects some of the communication with the control. It is used particularly in printing press applications provided it is a process computer node or regulator which is the sercos master in a drive ring. [0200] The task of the information broker “parameter demand data” is to make available any parameter values to one or more controls close to time. It will have the following capabilities: [0201] A control client sends any parameters in a requirement telegram to the information broker. This requests the parameter values with a high priority from the regulator and sends back a reply telegram to the control client. For communication with the control client, a proprietary protocol and/or TCP/IP may be used. [0202] Monitoring of the requirement telegrams [0203] For diagnosis purposes, it will be possible to forward the incoming telegrams from the control both to the process computer node or regulator and additionally to the diagnosis system. [0204] The task of the information broker “software download” is to transmit the regulator firmware and complete data records between the diagnosis computer node and the regulator. The transmission of data is effected by means of the FTP protocol. It will have the following capabilities: [0205] Download of a regulator firmware to the regulator as process computer node [0206] The download of regulator firmware is effected in two stages: first by means of an FTP client the firmware is transferred in a list on the flashcard of the communication PC. In the second stage, the information broker “software download” is instructed by means of an XML telegram to change the boot settings of the regulator in such a manner that the next time the regulator is booted up the new firmware is started. [0207] Upload of a regulator firmware as process computer node [0208] The upload of a regulator firmware is effected direct via the FTP protocol. In this case, no support on the part of the information broker “software download” is necessary. [0209] Download of a complete data record [0210] As in the download of a regulator firmware, the download of a parameter data record likewise takes place in two stages: [0211] First, by means of an FTP client, the data record in a list on the flashcard of the communication PC is transferred. In the second stage, the information broker “software download” is instructed by means of an XML telegram to change the settings of the regulator in such a manner that the next time the regulator is booted up the new data record is taken into account. [0212] Upload of a complete data record [0213] The upload of a data record is effected direct via the FTP protocol. In this case, no support on the part of the information broker “software download” is necessary. [0214] The task of the connection manager is to administer the interface to the regulator or process computer node. In this it will be possible to manage various physical interfaces (e.g. serial, Ethernet or SPI). Each enquiry to the connection manager is provided with one or 5 priority levels. Enquiries with the highest priority are sent by the connection manager to the (digital signal) processor process computer node before all other enquiries awaiting a response. Enquiries with a low priority are always dealt with after all other tasks awaiting. Thus it can be ensured that a task with the highest priority, e.g. from the control, is always processed as the next enquiry on the process computer node. [0215] In the process computer node, as a memory means a flashcard is allocated to the communication PC due to the improved support by the Intel PXA 255. However, for the process computer node or regulator, there has to be an option of reading parameters from the flashcard and to write them on to the flashcard. This is ensured by means of the parameter manager. [0216] Further services on the communication PC [0217] Logging servers [0218] All notices generated in the information broker processes are formatted and written to the console, into a log file or a message queue of the log server. This log server can then send the messages to any servers/computers. [0219] In order to permit subsequent evaluation of the log files, various message types are specified which simplify the interpretation of the messages (e.g. debug, data, error . . . ). [0220] Script support [0221] By means of script support on the communication PC, a versatile and freely programmable interface is to be created, with which future requirements of monitoring and diagnosis are to be covered. By means of a PERL interpreter, any scripts can run on the communication PC, which have access to the functionalities of the information brokers “parameters” and “errors and events”. Thus relatively complex monitoring functions can be carried out locally on the communication PC without loading the network by transmitting data. The scripts are transmitted by means of the FTP server to the communication PC or are already present there as part of the software. [0222] Due to the strenuous requirements for performance and system resources of the communication PC, the script support is only to be used for special diagnosis tasks. [0223] Time synchronisation, FTP server, Telnet [0224] For synchronisation of the system times, all communication PCs will synchronise their system time regularly via a time server running on the BAUDIS. [0225] The FTP server and Telnet access serve for software updating of the communication PC and for maintenance. [0226] Diagnosis data arising during operation of the drive system (e.g. errors or diagnosis information such as e.g. temperature, speed, contouring error, deviation from rules) are polled by the communication PC on the process computer node or drive regulator and converted into an XML-based protocol. The communication PC makes the diagnosis data available to the diagnosis computer node in an event-based manner (information broker “event”) or in an enquiry-based manner (information broker “parameter”). [0227] In the managers of the diagnosis computer node, the diagnosis data are retrieved or received in an event-based manner from the communication PC of the drive regulator and are further processed (e.g. storage in the database, converted etc.). If diagnosis data are to be displayed on the user interface, the manager forwards the diagnosis data to the appropriate components in the Servlet container. There the data are prepared, so that they can be transferred by means of enquiry-based communication (polling) or by means of event-based communication (event channel) via the data remote connection to the Java Applets, which are embedded in the user interface. [0228] FIGS. 6 and 7 show web-based user interfaces which graphically prepare the required diagnosis data for the user. Thus the diagnosis system according to the invention becomes an instrument which increases the machine availability and also makes complex appliances with a large number of drives manageable. Thus with the user interfaces of the type shown in FIGS. 7 and 8 , the machine control station can be supplied with data for the current machine status, or the production line can be provided with statistical data for machine availability and for maintenance cycles. But also the machine manufacturer or the drive supplier can thus have comfortable access to an appliance with a large number of technical-physical processes in order to afford rapid, efficient diagnosis and error correction during servicing. This is made possible by the user of modern web-based technologies or web-based user interfaces with their inherent versatility. Advantageously, the web interface can thus run on any client computer, independently of the respective client operating system. Installation of an user interface specific to the diagnosis system on the client computer node is no longer necessary. The web-based user interfaces are operable by the user in a customary and therefore easier manner due to the wide distribution by the Internet. The user interface can be adapted to the client's wishes at reasonable cost. [0229] List of Reference Numbers [0230] axle [0231] electric motor [0232] converter [0233] process computer node [0234] communication computer node [0235] switch cabinet [0236] SPS Control computer node. [0237] While certain preferred embodiments of the present invention have been disclosed in detail, it is to be understood that various modifications may be adopted without departing from the spirit of the invention or scope of the following claims. [0238] Key to the Drawings [0239] FIG. 1 [0240] Antriebs . . . —drive system [0241] Diagnoserechnerknoten—diagnosis computer node [0242] Leitstand—control station [0243] Diagnose—diagnosis [0244] Router od.ISDN/Analog—router or ISDN/analogue [0245] Femdiagnose—remote diagnosis [0246] FIG. 2 [0247] Diagnoserechnerknoten—diagnosis computer node [0248] Diagnosestationen—diagnosis stations [0249] FIG. 3 [0250] Prozessrechnerknoten—process computer node [0251] Kommunikationsrechnerknoten—communication computer node [0252] Diagnoserechnerknoten—diagnosis computer node [0253] Konfiguration—configuration [0254] Bedienung—operation [0255] Diagnose—diagnosis [0256] Client-Rechnerknoten—client computer node [0257] FIG. 4 [0258] Zur Prozess . . . —To the process computer plane [0259] Aufzeichnugs . . . —record manager [0260] Anlagenmanager—appliance manager [0261] Ereignis . . . —event manager [0262] Benutzer . . . —user manager [0263] Logging . . . —logging manager [0264] Anlagenubersicht—appliance monitoring [0265] Logbuch—logbook [0266] Aufzeichnung—record [0267] Visualisierung—visualisation [0268] Inbetriebnahme . . . —installation+service [0269] Wartung—maintenance [0270] Ereignisanzeige—event display [0271] Menu—menu [0272] Menuhandler—menu handler [0273] SOAP-Handler—SOAP handler [0274] Zyklische Daten—cyclical data [0275] Event+Heartbeat−event+heartbeat [0276] Diagnose-Rechner . . . —diagnosis computer node [0277] Firewall—firewall [0278] Zu den . . . —to the client computer node [0279] FIG. 5 [0280] Prozess . . . —process computer node [0281] Kommunikations . . . —communication computer node [0282] Proprietares protokoll—proprietary protocol [0283] Informationsbroker—information broker [0284] Parameter—parameters [0285] Fehler U. Events—errors and events [0286] Bedarfsdaten—demand data [0287] Zyklische Sollwerte—cyclical setpoint values [0288] Zeitzynchronisation—time synchronisation [0289] Telnet-Zugang—Telnet access [0290] Konfigurations . . . —configuration manager [0291] Skripte—script [0292] Logging Server—logging server [0293] Diagnose-Netz—diagnosis network [0294] Diagnose-Rechnerknoten—diagnosis computer node [0295] Steuerungs-Netz—control network [0296] Steuerung—control [0297] FIG. 6 [0298] Gesamtubersicht—Total monitoring [0299] Anlagenubersicht—appliance monitoring [0300] (reading down the left-hand column) [0301] Appliance status [0302] Appliance monitoring [0303] Logbook [0304] Diagnosis [0305] Record [0306] Visualisation [0307] Service [0308] Parameter monitor [0309] Maintenance [0310] Regulator administration [0311] Data records [0312] Events [0313] Secure drive [0314] Firmware update [0315] System functions [0316] Settings [0317] User management [0318] BAUDIS NET setup [0319] Documentation [0320] Log off [0321] FIG. 7 [0322] Antriebsystem—drive system [0323] Column on left reads same as for FIG. 6

The invention relates to a computer network for configuration, installation, monitoring, error-diagnosis and/or analysis of several physical technical processes, in particular electrical drive processes, which occur under the control, regulation and/or monitoring of several process computer nodes, connected by means of at least one common communication system to at least one diagnosis computer node, in which one or several configuration, monitoring and diagnosis services and/or functions are implemented, provided for the processes and/or the process computer nodes and/or the data processing processes running therein, whereby the common communication system is achieved by means of the Ethernet, or a similar asynchronous and/or bus or communication system working with a stochastic access method.

[0001] This application is a continuation of U.S. patent application Ser. No. 14/176,975, filed Feb. 10, 2014, now U.S. Pat. No. 9,179,477, which is a continuation of U.S. patent application Ser. No. 13/297,206, filed Nov. 15, 2011, now U.S. Pat. No. 8,649,321 and is a continuation of U.S. patent application Ser. No. 12/124,083, filed on May 20, 2008, now U.S. Pat. No. 8,068,449, which is a continuation of U.S. patent application Ser. No. 11/555,244 filed on Oct. 31, 2006, now U.S. Pat. No. 7,379,432, which is a continuation of U.S. patent application Ser. No. 10/187,158 filed on Jun. 28, 2002, now U.S. Pat. No. 7,136,361, which claims priority from U.S. Provisional Patent Application Nos. 60/302,661, filed Jul. 5, 2001; 60/304,122, filed Jul. 11, 2001; and 60/317,933, filed Sep. 10, 2001, all of above cited applications are incorporated herein by reference. RELATED APPLICATIONS [0002] This patent application is related to U.S. patent application Ser. No. 09/985,257, filed Nov. 2, 2001, now U.S. Pat. No. 7,095,754, which is incorporated by reference. FIELD OF THE INVENTION [0003] The invention disclosed broadly relates to telecommunications methods and more particularly relates to Quality of Service (QoS) management in multiple access packet networks. BACKGROUND OF THE INVENTION [0004] Wireless Local Area Networks (WLANS) [0005] Wireless local area networks (WLANs) generally operate at peak speeds of between 10 to 100 Mbps and have a typical range of 100 meters. Single cell Wireless LANs, are suitable for small single-floor offices or stores. A station in a wireless LAN can be a personal computer, a bar code scanner, or other mobile or stationary device that uses a wireless network interface card (NIC) to make the connection, over the RF link to other stations in the network. The single-cell wireless LAN provides connectivity within radio range between wireless stations. An access point allows connections via the backbone network, to wired network-based resources, such as servers. A single cell wireless LAN can typically support up to 25 users and still keep network access delays at an acceptable level. Multiple cell wireless LANs provide greater range than does a single cell, by means of a set of access points and a wired network backbone to interconnect a plurality of single cell LANs. Multiple cell wireless LANs can cover larger multiple-floor buildings. A mobile laptop computer or data collector with a wireless network interface card (NIC) can roam within the coverage area while maintaining a live connection to the backbone network. [0006] Wireless LAN specifications and standards include the IEEE 802.11 Wireless LAN Standard and the HIPERLAN Type 1 and Type 2 Standards. The IEEE 802.11 Wireless LAN Standard is published in three parts as IEEE 802.11-1999; IEEE 802.11a-1999; and IEEE 802.11b-1999, which are available from the IEEE, Inc. web site http://grouperleee.org/groups/802/11. An overview of the HIPERLAN Type 1 principles of operation is provided in the publication HIPERLAN Type 1 Standard, ETSI ETS 300 652, WA2 Dec. 1997. An overview of the HIPERLAN Type 2 principles of operation is provided in the Broadband Radio Access Networks (BRAN), HIPERLAN Type 2; System Overview, ETSI TR 101 683 VI.I.1 (2000-02) and a more detailed specification of its network architecture is described in HIPERLAN Type 2, Data Link Control (DLC) Layer; Part 4. Extension for Home Environment, ETSI TS 101 761-4 V1.2.1 (2000-12). A subset of wireless LANs is Wireless Personal Area Networks (PANs), of which the Bluetooth Standard is the best known. The Bluetooth Special Interest Group, Specification Of The Bluetooth System, Version 1.1, Feb. 22, 2001, describes the principles of Bluetooth device operation and communication protocols. [0007] The IEEE 802.11 Wireless LAN Standard defines at least two different physical (PHY) specifications and one common medium access control (MAC) specification. The IEEE 802.11(a) Standard is designed to operate in unlicensed portions of the radio spectrum, usually either in the 2.4 GHz Industrial, Scientific, and Medical (ISM) band or the 5 GHz Unlicensed-National Information Infrastructure (U-NIT) band. It uses orthogonal frequency division multiplexing (OFDM) to deliver up to 54 Mbps data rates. The IEEE 802.11(b) Standard is designed for the 2.4 GHz ISM band and uses direct sequence spread spectrum (DSSS) to deliver up to 11 Mbps data rates. The IEEE 802.11 Wireless LAN Standard describes two major components, the mobile station and the fixed access point (AP). IEEE 802.11 networks can also have an independent configuration where the mobile stations communicate directly with one another, without support from a fixed access point. [0008] A single cell wireless LAN using the IEEE 802.11 Wireless LAN Standard is an Independent Basic Service Set (IBSS) network. An IBSS has an optional backbone network and consists of at least two wireless stations. A multiple cell wireless LAN using the IEEE 802.11 Wireless LAN Standard is an Extended Service Set (ESS) network. An ESS satisfies the needs of large coverage networks of arbitrary size and complexity. [0009] Each wireless station and access point in an IEEE 802.11 wireless LAN implements the MAC layer service, which provides the capability for wireless stations to exchange MAC frames. The MAC frame transmits management, control, or data between wireless stations and access points. After a station forms the applicable MAC frame, the frame's bits are passed to the Physical Layer for transmission. [0010] Before transmitting a frame, the MAC layer must first gain access to the network. Three interframe space (IFS) intervals defer an IEEE 802.11 station's access to the medium and provide various levels of priority. Each interval defines the duration between the end of the last symbol of the previous frame, to the beginning of the first symbol of the next frame. The Short Interframe Space (SIFS) provides the highest priority level by allowing some frames to access the medium before others, such as an Acknowledgement (ACK) frame, a Clear to Send (CTS) frame, or a subsequent fragment burst of a previous data frame. These frames require expedited access to the network to minimize frame retransmissions. [0011] The Priority Interframe Space (PIFS) is used for high priority access to the medium during the contention-free period. The point coordinator in the access point connected to backbone network, controls the priority-based Point Coordination Function (PCF) to dictate which stations in cell can gain access to the medium. The point coordinator in the access point sends a contention-free poll frame to a station, granting the station permission to transmit a single frame to any destination. All other stations in the cell can only transmit during contention-free period if the point coordinator grants them access to the medium. The end of the contention-free period is signaled by the contention-free end frame sent by the point coordinator, which occurs when time expires or when the point coordinator has no further frames to transmit and no stations to poll. [0012] The distributed coordination function (DCF) Interframe Space (DIFS) is used for transmitting low priority data frames during the contention-based period. The DIFS spacing delays the transmission of lower priority frames to occur later than the priority-based transmission frames. An Extended Interframe Space (EIFS) goes beyond the time of a DIFS interval, as a waiting period when a bad reception occurs. The EIFS interval provides enough time for the receiving station to send an acknowledgment (ACK) frame. [0013] During the contention-based period, the distributed coordination function (DCF) uses the Carrier-Sense Multiple Access With Collision Avoidance (CSMA/CA) contention-based protocol, which is similar to IEEE 802.3 Ethernet. The CSMA/CA protocol minimizes the chance of collisions between stations sharing the medium, by waiting a random backoff interval, if the station's sensing mechanism indicates a busy medium. The period of time immediately following traffic on the medium is when the highest probability of collisions occurs, especially where there is high utilization. Once the medium is idle, CSMA/CA protocol causes each station to delay its transmission by a random backoff time, thereby minimizing the chance it will collide with those from other stations. [0014] The CSMA/CA protocol computes the random backoff time as the product of a constant, the slot time, times a pseudo-random number RN which has a range of values from zero to a collision window CW. The value of the collision window for the first try to access the network is CW1, which yields the first try random backoff time. If the first try to access the network by a station fails, then the CSMA/CA protocol computes a new CW by doubling the current value of CW as CW2=CW1 times 2. The value of the collision window for the second try to access the network is CW2, which yields the second try random backoff time. This process by the CSMA/CA protocol of increasing the delay before transmission is called binary exponential backoff. The reason for increasing CW is to minimize collisions and maximize throughput for both low and high network utilization. Stations with low network utilization are not forced to wait very long before transmitting their frame. On the first or second attempt, a station will make a successful transmission. However, if the utilization of the network is high, the CSMA/CA protocol delays stations for longer periods to avoid the chance of multiple stations transmitting at the same time. If the second try to access the network fails, then the CSMA/CA protocol computes a new CW by again doubling the current value of CW as CW3=CW1 times 4. The value of the collision window for the third try to access the network is CW3, which yields the third try random backoff time. The value of CW increases to relatively high values after successive retransmissions, under high traffic loads. This provides greater transmission spacing between stations waiting to transmit. Collision Avoidance Techniques [0015] Four general collision avoidance approaches have emerged: [1] Carrier Sense Multiple Access (CSMA) [see, F. Tobagi and L. Kleinrock, “Packet Switching in Radio Channels: Part I—Carrier Sense Multiple Access Models and their Throughput Delay Characteristics”, IEEE Transactions on Communications, Vol 23, No 12, Pages 1400-1416, 1975], [2] Multiple Access Collision Avoidance (MACA) [see, P. Karn, “MACA—A New Channel Access Protocol for Wireless Ad-Hoc Networks”, Proceedings of the ARRL/CRRL Amateur Radio Ninth Computer Networking Conference, Pages 134-140, 1990], [3] their combination CSMA/CA, and [4] collision avoidance tree expansion. [0016] CSMA allows access attempts after sensing the channel for activity. Still, simultaneous transmit attempts lead to collisions, thus rendering the protocol unstable at high traffic loads. The protocol also suffers from the hidden terminal problem. [0017] The latter problem was resolved by the MACA protocol, which involves a three-way handshake [P. Karn, supra]. The origin node sends a request to send (RTS) notice of the impending transmission. A response is returned by the destination if the RTS notice is received successfully and the origin node proceeds with the transmission. This protocol also reduces the average delay as collisions are detected upon transmission of merely a short message, the RTS. With the length of the packet included in the RTS and echoed in the clear to send (CTS) messages, hidden terminals can avoid colliding with the transmitted message. However, this prevents the back-to-back re-transmission in case of unsuccessfully transmitted packets. A five-way handshake MACA protocol provides notification to competing sources of the successful termination of the transmission. [see, V. Bharghavan, A. Demiers, S. Shenker, and L. Zhang, “MACAW: A media access protocol for wireless LANs, SIGCOMM '94, Pages 212-225, ACM, 1994.] [0018] CSMA and MACA are combined in CSMA/CA, which is MACA with carrier sensing, to give better performance at high loads. A four-way handshake is employed in the basic contention-based access protocol used in the Distributed Coordination Function (DCF) of the IEEE 802.11 Standard for Wireless LANs. [see, IEEE Standards Department, D3, “Wireless Medium Access Control and Physical Layer WG,” IEEE Draft Standard P802.11 Wireless LAN, January 1996.] [0019] Collisions can be avoided by splitting the contending terminals before transmission is attempted. In the pseudo-Bayesian control method, each terminal determines whether it has permission to transmit using a random number generator and a permission probability “p” that depends on the estimated backlog. [see, R. L. Rivest, “Network control by Bayesian Broadcast”, IEEE Trans. Inform. Theory, Vol IT 25, pp. 505-515, September 1979] [0020] To resolve collisions, subsequent transmission attempts are typically staggered randomly in time using the following two approaches: binary tree and binary exponential backoff. [0021] Upon collision, the binary tree method requires the contending nodes to self-partition into two groups with specified probabilities. This process is repeated with each new collision. The order in which contending nodes transmit is determined either by serial or parallel resolution of the tree. [see, J. L. Massey, “Collision-resolution algorithms and random-access communications”, in Multi-User Communication Systems, G. Longo (ed.), CISM Courses and Lectures No. 265. New York: Springer 1982, pp. 73-137.] [0022] In the binary exponential backoff approach, a backoff counter tracks the number of pauses and hence the number of completed transmissions before a node with pending packets attempts to seize the channel. A contending node initializes its backoff counter by drawing a random value, given the backoff window size. Each time the channel is found idle, the backoff counter is decreased and transmission is attempted upon expiration of the backoff counter. The window size is doubled every time a collision occurs, and the backoff countdown starts again. [see, A. Tanenbaum, Computer Networks, 3 rd ed., Upper Saddle River, N.J., Prentice Hall, 1996] The Distributed Coordination Function (DCF) of the IEEE 802.11 Standard for Wireless LANs employs a variant of this contention resolution scheme, a truncated binary exponential backoff, starting at a specified window and allowing up to a maximum backoff range below which transmission is attempted. [IEEE Standards Department, D3, supra] Different backoff counters may be maintained by a contending node for traffic to specific destinations. [Bharghavan, supra] In the IEEE 802.11 Standard, the channel is shared by a centralized access protocol, the Point Coordination Function (PCF), which provides contention-free transfer based on a polling scheme controlled by the access point (AP) of a basic service set (BSS). [IEEE Standards Department, D3, supra] The centralized access protocol gains control of the channel and maintains control for the entire contention-free period by waiting a shorter time between transmissions than the stations using the Distributed Coordination Function (DCF) access procedure. Following the end of the contention-free period, the DCF access procedure begins, with each station contending for access using the CSMA/CA method. [0023] The 802.11 MAC Layer provides both contention and contention-free access to the shared wireless medium. The MAC Layer uses various MAC frame types to implement its functions of MAC management, control, and data transmission. Each station and access point on an 802.11 wireless LAN implements the MAC Layer service, which enables stations to exchange packets. The results of sensing the channel to determine whether the medium is busy or idle, are sent to the MAC coordination function of the station. The MAC coordination also carries out a virtual carrier sense protocol based on reservation information found in the Duration Field of all frames. This information announces to all other stations, the sending station's impending use of the medium. The MAC coordination monitors the Duration Field in all MAC frames and places this information in the station's Network Allocation Vector (NAV) if the value is greater than the current NAV value. The NAV operates similarly to a timer, starting with a value equal to the Duration Field of the last frame transmission sensed on the medium, and counting down to zero. After the NAV reaches zero, the station can transmit, if its physical sensing of the channel indicates a clear channel. [0024] At the beginning of a contention-free period, the access point senses the medium, and if it is idle, it sends a Beacon packet to all stations. The Beacon packet contains the length of the contention-free interval. The MAC coordination in each member station places the length of the contention-free interval in the station's Network Allocation Vector (NAV), which prevents the station from taking control of the medium until the end of the contention-free period. During the contention-free period, the access point can send a polling message to a member station, enabling it to send a data packet to any other station in the BSS wireless cell. Quality of Service (QoS) [0025] Quality of service (QoS) is a measure of service quality provided to a customer. The primary measures of QoS are message loss, message delay, and network availability. Voice and video applications have the most rigorous delay and loss requirements. Interactive data applications such as Web browsing have less restrained delay and loss requirements, but they are sensitive to errors. Non-real-time applications such as file transfer, Email, and data backup operate acceptably across a wide range of loss rates and delay. Some applications require a minimum amount of capacity to operate at all, for example, voice and video. Many network providers guarantee specific QoS and capacity levels through the use of Service-Level Agreements (SLAs). An SLA is a contract between an enterprise user and a network provider that specifies the capacity to be provided between points in the network that must be delivered with a specified QoS. If the network provider fails to meet the terms of the SLA, then the user may be entitled a refund. The SLA is typically offered by network providers for private line, frame relay, ATM, or Internet networks employed by enterprises. [0026] The transmission of time-sensitive and data application traffic over a packet network imposes requirements on the delay or delay jitter, and the error rates realized; these parameters are referred to generically as the QoS (Quality of Service) parameters. Prioritized packet scheduling, preferential packet dropping, and bandwidth allocation are among the techniques available at the various nodes of the network, including access points, that enable packets from different applications to be treated differently, helping achieve the different quality of service objectives. Such techniques exist in centralized and distributed variations. The concern herein is with distributed mechanisms for multiple access in cellular packet networks or wireless ad hoc networks. [0027] Management of contention for the shared transmission medium must reflect the goals sought for the performance of the overall system. For instance, one such goal would be the maximization of goodput (the amount of good data transmitted as a fraction of the channel capacity) for the entire system, or of the utilization efficiency of the RF spectrum; another is the minimization of the worst-case delay. As multiple types of traffic with different performance requirements are combined into packet streams that compete for the same transmission medium, a multi-objective optimization is required. [0028] Ideally, one would want a multiple access protocol that is capable of effecting packet transmission scheduling as close to the optimal scheduling as possible, but with distributed control. Distributed control implies both some knowledge of the attributes of the competing packet sources and limited control mechanisms. [0029] To apply any scheduling algorithm in random multiple access, a mechanism must exist that imposes an order in which packets will seize the medium. For distributed control, this ordering must be achieved independently, without any prompting or coordination from a control node. Only if there is a reasonable likelihood that packet transmissions will be ordered according to the scheduling algorithm, can one expect that the algorithm's proclaimed objective will be attained. [0030] The above cited, copending patent application by Mathilde Benveniste, entitled “Tiered Contention Multiple Access (TCMA): A Method for Priority-Based Shared Channel Access”, describes the Tiered Contention Multiple Access (TCMA) distributed medium access protocol that schedules transmission of different types of traffic based on their QoS service quality specifications. This protocol makes changes to the contention window following the transmission of a frame, and therefore is also called Extended-DCF (E-DCF). During the contention window, the various stations on the network contend for access to the network. To avoid collisions, the MAC protocol requires that each station first wait for a randomly-chosen time period, called an arbitration time. Since this period is chosen at random by each station, there is less likelihood of collisions between stations. TCMA uses the contention window to give higher priority to some stations than to others. Assigning a short contention window to those stations that should have higher priority ensures that in most cases, the higher-priority stations will be able to transmit ahead of the lower-priority stations. TCMA schedules transmission of different types of traffic based on their QoS service quality specifications. As seen in FIG. 1 , which depicts the tiered contention mechanism, a station cannot engage in backoff countdown until the completion of an idle period of length equal to its arbitration time. [0031] The above cited, copending patent application by Mathilde Benveniste also applies TCMA to the use of the wireless access point as a traffic director. This application of the TCMA protocol is called the hybrid coordination function (HCF). In HCF, the access point uses a polling technique as the traffic control mechanism. The access point sends polling packets to a succession of stations on the network. The individual stations can reply to the poll with a packet that contains not only the response, but also any data that needs to be transmitted. Each station must wait to be polled. The access point establishes a polling priority based on the QoS priority of each station. [0032] What is needed in the prior art is a way to apply the hybrid coordination function (HCF) to wireless cells that have overlapping access points contending for the same medium. SUMMARY OF THE INVENTION [0033] In accordance with the invention, the Tiered Contention Multiple Access (TCMA) protocol is applied to wireless cells which have overlapping access points contending for the same medium. Quality of Service (QoS) support is provided to overlapping access points to schedule transmission of different types of traffic based on the service quality specifications of the access points. [0034] The inventive method reduces interference in a medium between overlapping wireless LAN cells, each cell including an access point station and a plurality of member stations. In accordance with the invention, the method assigns to a first access point station in a first wireless LAN cell, a first scheduling tag. The scheduling tag has a value that determines an accessing order for the cell in a transmission frame, with respect to the accessing order of other wireless cells. The scheduling tag value is deterministically set. The scheduling tag value can be permanently assigned to the access point by its manufacturer, it can be assigned by the network administrator at network startup, it can be assigned by a global processor that coordinates a plurality of wireless cells over a backbone network, it can be drawn from a pool of possible tag values during an initial handshake negotiation with other wireless stations, or it can be cyclically permuted in real-time, on a frame-by-frame basis, from a pool of possible values, coordinating that cyclic permutation with that of other access points in other wireless cells. [0035] An access point station in a wireless cell signals the beginning of an intra-cell contention-free period for member stations in its cell by transmitting a beacon packet. The duration of the intra-cell contention-free period is deterministically set. The member stations in the cell store the intra-cell contention-free period value as a Network Allocation Vector (NAV). Each member station in the cell decrements the value of the NAV in a manner similar to other backoff time values, during which it will delay accessing the medium. [0036] In accordance with the invention, the method assigns to the first access point station, a first inter-cell contention-free period value, which gives notice to any other cell receiving the beacon packet, that the first cell has seized the medium for the period of time represented by the value. The inter-cell contention-free period value is deterministically set. Further in accordance with the invention, any station receiving the beacon packet immediately broadcasts a contention-free time response (CFTR) packet containing a copy of the first inter-cell contention-free period value. In this manner, the notice is distributed to a second access point station in an overlapping, second cell. The second access point stores the first inter-cell contention-free period value as an Inter-BSS Network Allocation Vector (IBNAV). The second access point decrements the value of IBNAV in a manner similar to other backoff time values, during which it will delay accessing the medium. [0037] Still further in accordance with the invention, the method also assigns to first member stations in the first cell, a first shorter backoff value for high Quality of Service (QoS) data and a first longer backoff value for lower QoS data. The backoff time is the interval that a member station waits after the expiration of the contention-free period, before the member station contends for access to the medium. Since more than one member station in a cell may be competing for access, the actual backoff time for a particular station can be selected as one of several possible values. In one embodiment, the actual backoff time for each particular station is deterministically set, so as to reduce the length of idle periods. In another embodiment, the actual backoff time for each particular station is randomly drawn from a range of possible values between a minimum delay interval to a maximum delay interval. The range of possible backoff time values is a contention window. The backoff values assigned to a cell may be in the form of a specified contention window. High QoS data is typically isochronous data such as streaming video or audio data that must arrive at its destination at regular intervals. Low QoS data is typically file transfer data and email, which can be delayed in its delivery and yet still be acceptable. The Tiered Contention Multiple Access (TCMA) protocol coordinates the transmission of packets within a cell, so as to give preference to high QoS data over low QoS data, to insure that the required quality of service is maintained for each type of data. [0038] The method similarly assigns to a second access point station in a second wireless LAN cell that overlaps the first cell, a second contention-free period value longer than the first contention-free period value. The method also assigns to second member stations in the second cell, a second shorter backoff value for high QoS data and a second longer backoff value for lower QoS data. The first and second cells are considered to be overlapped when one or more stations in the first cell inadvertently receive packets from member stations or the access point of the other cell. The invention reduces the interference between the overlapped cells by coordinating the timing of their respective transmissions, while maintaining the TCMA protocol's preference for the transmission of high QoS data over low QoS data in each respective cell. [0039] During the operation of two overlapped cells, the method transmits a first beacon packet including the intra-cell contention-free period value (the increment to the NAV) and inter-cell contention-free period value (the CFTR), from the first access point to the first member stations in the first cell. The beacon packet is received by the member stations of the first cell and can be inadvertently received by at least one overlapped member station of the second cell. Each member station in the first cell increments its NAV with the intra-cell contention-free period value and stores the inter-cell contention-free period value as the CFTR. [0040] In accordance with the invention, each station that receives the first beacon packet, immediately responds by transmitting a first contention-free time response (CFTR) packet that contains a copy of the inter-cell contention-free period value (CFTR). A CFTR packet is transmitted from the first member stations in the first cell and also by the overlapped member stations of the second cell. The effect of the transmission of CFTR packets from member stations in the second cell is to alert the second access point and the second member stations in the second cell, that the medium has been seized by the first access point in the first cell. When the second access point in the second cell receives the CFTR packet it stores a copy of the inter-cell contention-free period value as the IBNAV. [0041] Similar to a station's Network Allocation Vector (NAV), a first IBNAV is set at the second access point to indicate the time the medium will be free again. Also similar to the NAV, the first IBNAV is decremented with each succeeding slot, similar to the decrementing of other backoff times. When the second access point receives the first IBNAV representing the first cell's contention-free period value, the second access point must respect the first IBNAV value and delay transmitting its beacon packet and the exchange of other packets in the second cell until the expiration of the received, first IBNAV. [0042] When the second access point has decremented the first IBNAV to zero, the second access point transmits its second beacon packet including its second contention-free period values of NAV and a second IBNAV, to the second member stations in the second cell. Each station that receives the second beacon packet immediately responds by transmitting a second contention-free time response (CFTR) packet that contains a copy of the second IBNAV inter-cell contention-free period value. The second CFTR packet is transmitted from the second member stations in the second cell and also by the overlapped member stations of the first cell. The effect of the transmission of the second CFTR packets from overlapped member stations in the first cell is to alert the first access point and the first member stations in the first cell, that the medium has been seized by the second access point in the second cell. When the first access point in the first cell receives the CFTR packet, it stores a copy of the second IBNAV inter-cell contention-free period value, to indicate the time the medium will be free again. The second IBNAV is decremented with each succeeding frame, similar to the decrementing of other backoff times. [0043] The second member stations in the second cell wait for completion of the countdown of their NAVs to begin the TCMA protocol of counting down the second shorter backoff for high QoS data and then transmitting second high QoS data packets. [0044] Meanwhile, the first access point in the first cell waits for completion of the countdown of the second IBNAV inter-cell contention-free period before starting the countdown of its own NAV for its own intra-cell contention-free period. The first member stations in the first cell wait for the countdown of their NAVs, to begin the TCMA protocol of counting down the first longer backoff for low QoS data and then transmitting first low QoS data. [0045] Meanwhile the second member stations are waiting for the TCMA protocol of counting down the second longer backoff for lower QoS data before transmitting the second lower QoS data. [0046] In this manner, interference in a medium between overlapping wireless LAN cells is reduced. [0047] Potential collisions between cells engaged in centralized access can be averted or resolved by the TCMA protocol. In accordance with the invention, deterministically set backoff delays are used, which tend to reduce the length of the idle periods. The possibility of coincident or overlapping contention-free periods between neighboring cells is eliminated through the use of an “interference sensing” method employing a new frame. [0048] The invention enables communication of channel occupancy information to neighboring access points. When a beacon packet is transmitted, and before transmission of any other data or polling packets, all stations hearing the beacon will respond by sending a frame, the contention-free time response (CFTR), that will contain the duration of the contention-free period found in the beacon. An access point in neighboring cells, or stations attempting contention-based channel access, which receive this message from a station in the cell overlapping region, are thus alerted that the channel has been seized by an access point. Similar to a station's Network Allocation Vector (NAV), an Inter-Cell Network Allocation Vector at the access point accordingly indicates when the time the channel will be free again. Unless the Inter-Cell Network Allocation Vector is reset, the access point will decrease its backoff value only after the expiration of the Inter-Cell Network Allocation Vector, according to the backoff countdown rules. [0049] In another aspect of the invention, potential collisions between different access points engaged in centralized access cart be averted or resolved by using deterministic backoff delays, which avoid collisions between access points, and eliminate gaps between consecutive poll/response exchanges or contention-free bursts (CFBs) between the access point and its associated stations. [0050] The resulting invention applies the Tiered Contention Multiple Access (TCMA) protocol to wireless cells which have overlapping access points contending for the same medium. DESCRIPTION OF THE FIGURES [0051] FIG. 1 depicts the tiered contention mechanism. [0052] FIG. 1A through 1J show the interaction of two wireless LAN cells which have overlapping access points contending for the same medium, in accordance with the invention. [0053] FIG. 1K shows a timing diagram for the interaction of two wireless LAN cells in FIG. 1A through 1J , in accordance with the invention. [0054] FIG. 1L shows the IEEE 802.11 packet structure for a beacon packet, including the increment to the NAV period and the CFTR period, in accordance with the invention. [0055] FIG. 1M shows the IEEE 802.11 packet structure for a CFTR packet, including the CFTR period, in accordance with the invention. [0056] FIG. 2 illustrates the ordering of transmissions from three groups of BSSs. [0057] FIG. 3 illustrates how three interfering BSSs share the same channel for two consecutive frames. [0058] FIG. 4 illustrates how three interfering BSSs, each with two types of traffic of different priorities, share the same channel in two consecutive frames. [0059] FIGS. 5 ( 5 a and 5 b ) illustrates the possible re-use of tags. [0060] FIG. 6 illustrates the deterministic post-backoff. [0061] FIG. 7 shows the relationships of repeating sequences of CFBs. [0062] FIG. 8 illustrates the role of pegging in a sequence of CFBs by three overlapping access points. [0063] FIG. 9 illustrates the start-up procedure for a new access point, HC 2 , given an existing access point, HC 1 . [0064] FIG. 10 shows the relationship of repeating sequences of Tier I CFBs. [0065] FIG. 11 illustrates the start-up procedure for a new access point, HC 2 , given an existing access point, HC 1 . DISCUSSION OF THE PREFERRED EMBODIMENT [0066] The invention disclosed broadly relates to telecommunications methods and more particularly relates to Quality-of-Service (QoS) management in multiple access packet networks. Several protocols, either centralized or distributed can co-exist on the same channel through the Tiered Contention Multiple Access method. The proper arbitration time to be assigned to the centralized access protocol must satisfy the following requirements: (i) the centralized access protocol enjoys top priority access, (ii) once the centralized protocol seizes the channel, it maintains To control until the contention-free period ends, (iii) the protocols are backward compatible, and (iv) Overlapping Basic Service Sets (OBSSs) engaged in centralized-protocol can share the channel efficiently. [0067] In accordance with the invention, the Tiered Contention Multiple Access (TCMA) protocol is applied to wireless cells which have overlapping access points contending for the same medium. Quality of Service (QoS) support is provided to overlapping access points to schedule transmission of different types of traffic based on the service quality specifications of the access points. [0068] The inventive method reduces interference in a medium between overlapping wireless LAN cells, each cell including an access point station and a plurality of member stations. FIGS. 1A through 1J show the interaction of two wireless LAN cells which have overlapping access points contending for the same medium, in accordance with the invention. The method assigns to a first access point station in a first wireless LAN cell, a first scheduling tag. The scheduling tag has a value that determines an accessing order for the cell in a transmission frame, with respect to the accessing order of other wireless cells. The scheduling tag value is deterministically set. The scheduling tag value can be permanently assigned to the access point by its manufacturer, it can be assigned by the network administrator at network startup, it can be assigned by a global processor that coordinates a plurality of wireless cells over a backbone network, it can be drawn from a pool of possible tag values during an initial handshake negotiation with other wireless stations, or it can be cyclically permuted in real-time, on a frame-by-frame basis, from a pool of possible values, coordinating that cyclic permutation with that of other access points in other wireless cells. [0069] The interaction of the two wireless LAN cells 100 and 150 in FIGS. 1A through 1J is shown in the timing diagram of FIG. 1K . The timing diagram of FIG. 1K begins at instant T 0 , goes to instant T 9 , and includes periods P 1 through P 8 , as shown in the figure. The various packets discussed below are also shown in FIG. 1K , placed at their respective times of occurrence. An access point station in a wireless cell signals the beginning of an intra-cell contention-free period for member stations in its cell by transmitting a beacon packet. FIG. 1A shows access point 152 of cell 150 connected to backbone network 160 , transmitting the beacon packet 124 . In accordance with the invention, the beacon packet 124 includes two contention-free period values, the first is the Network Allocation Vector (NAV) (or alternately its incremental value ΔNAV), which specifies a period value P 3 for the intra-cell contention-free period for member stations in its own cell. Member stations within the cell 150 must wait for the period P 3 before beginning the Tiered Contention Multiple Access (TCMA) procedure, as shown in FIG. 1K . The other contention-free period value included in the beacon packet 124 is the Inter-BSS Network Allocation Vector (IBNAV), which specifies the contention-free time response (CFTR) period P 4 . The contention-free time response (CFTR) period P 4 gives notice to any other cell receiving the beacon packet, such as cell 100 , that the first cell 150 has seized the medium for the period of time represented by the value P 4 . [0070] The beacon packet 124 is received by the member stations 154 A (with a low QoS requirement 164 A) and 154 B (with a high QoS requirement 164 B) in the cell 150 during the period from T 1 to T 2 . The member stations 154 A and 154 B store the value of ΔNAV=P 3 and begin counting down that value during the contention free period of the cell 150 . The duration of the intra-cell contention-free period ΔNAV=P 3 is deterministically set. The member stations in the cell store the intra-cell contention-free period value P 3 as the Network Allocation Vector (NAV). Each member station in the cell 150 decrements the value of the NAV in a manner similar to other backoff time values, during which it will delay accessing the medium. FIG. 1L shows the IEEE 802.11 packet structure 260 for the beacon packet 124 or 120 , including the increment to the NAV period and the CFTR period. The beacon packet structure 260 includes fields 261 to 267 . Field 267 specifies the ΔNAV value of P 3 and the CFTR value of P 4 . In accordance with the invention, the method assigns to the first access point station, a first inter-cell contention-free period value, which gives notice to any other cell receiving the beacon packet, that the first cell has seized the medium for the period of time represented by the value. The inter-cell contention-free period value is deterministically set. [0071] Further in accordance with the invention, any station receiving the beacon packet 124 immediately rebroadcasts a contention-free time response (CFTR) packet 126 containing a copy of the first inter-cell contention-free period value P 4 . The value P 4 specifies the Inter-BSS Network Allocation Vector (IBNAV), i.e., the contention-free time response (CFTR) period that the second access point 102 must wait, while the first cell 150 has seized the medium. FIG. 1B shows overlap station 106 in the region of overlap 170 transmitting the CFTR packet 126 to stations in both cells 100 and 150 during the period front T 1 to T 2 . FIG. 1M shows the IEEE 802.11 packet structure 360 for a CFTR packet 126 or 122 , including the CFTR period. The CFTR packet structure 360 includes fields 361 to 367 . Field 367 specifies the CFTR value of P 4 . In this manner, the notice is distributed to the second access point station 102 in the overlapping, second cell 100 . [0072] FIG. 1C shows the point coordinator in access point 152 of cell 150 controlling the contention-free period within the cell 150 by using the polling packet 128 during the period from T 2 to T 3 . In the mean time, the second access point 102 in the second cell 100 connected to backbone network 110 , stores the first inter-cell contention-free period value P 4 received in the CFTR packet 126 , which it stores as the Inter-BSS Network Allocation Vector (IBNAV). The second access point 102 decrements the value of IBNAV in a manner similar to other backoff time values, during which it will delay accessing the medium. [0073] Still further in accordance with the invention, the method uses the Tiered Contention Multiple Access (TCMA) protocol to assign to first member stations in the first cell 150 , a first shorter backoff value for high Quality of Service (QoS) data and a first longer backoff value for lower QoS data. FIG. 1D shows the station 154 B in the cell 150 , having a high QoS requirement 164 B, decreasing its High QoS backoff period to zero and beginning TCMA contention to transmit its high QoS data packet 130 during the period from T 3 to T 4 . The backoff time is the interval that a member station waits after the expiration of the contention-free period P 3 , before the member station 154 B contends for access to the medium. Since more than one member station in a cell may be competing for access, the actual backoff time for a particular station can be selected as one of several possible values. In one embodiment, the actual backoff time for each particular station is deterministically set, so as to reduce the length of idle periods. In another embodiment, the actual backoff time for each particular station is randomly drawn from a range of possible values between a minimum delay interval to a maximum delay interval. The range of possible backoff time values is a contention window. The backoff values assigned to a cell may be in the form of a specified contention window. High QoS data is typically isochronous data such as streaming video or audio data that must arrive at its destination at regular intervals. Low QoS data is typically file transfer data and email, which can be delayed in its delivery and yet still be acceptable. The Tiered Contention Multiple Access (TCMA) protocol coordinates the transmission of packets within a cell, so as to give preference to high QoS data over low QoS data, to insure that the required quality of service is maintained for each type of data. [0074] The method similarly assigns to the second access point 102 station in the second wireless LAN cell 100 that overlaps the first sell 150 , a second contention-free period value CFTR=P 7 longer than the first contention-free period value CFTR=P 4 . FIG. 1E shows the second access point 102 in the cell 100 transmitting its beacon packet 120 including its contention-free period values of NAV (P 6 ) and IBNAV (P 7 ), to the member stations 104 A (with a low QoS requirement 114 A), 104 B (with a high QoS requirement 114 B) and 106 in the cell 100 during the period from T 4 to T 5 . FIG. 1F shows that each station, including the overlap station 106 , that receives the second beacon packet 120 , immediately responds by retransmitting a second contention-free time response (CFTR) packet 122 that contains a copy of the second inter-cell contention-free period value P 7 during the period from T 4 to T 5 . [0075] FIG. 1G shows the point coordinator in access point 102 of cell 100 controlling the contention-free period within cell 100 using the polling packet 132 during the period from T 5 to T 6 . [0076] The method uses the Tiered Contention Multiple Access (TCMA) protocol to assign to second member stations in the second cell 100 , a second shorter backoff value for high QoS data and a second longer backoff value for lower QoS data. FIG. 1H shows the station 104 B in the cell 100 , having a high QoS requirement 114 B, decreasing its High QoS backoff period to zero and beginning TCMA contention to transmit its high QoS data packet 134 during the period from T 6 to T 7 . FIG. 1I shows the first member stations 154 A and 154 B in the first cell 150 waiting for the countdown of their NAVs, to begin the TCMA protocol of counting down the first longer backoff for low QoS data and then transmitting first low QoS data 136 during the period from T 7 to T 8 . FIG. 1J shows the second member stations 104 A, 104 B, and 106 are waiting for the TCMA protocol of counting down the second longer backoff for lower QoS data before transmitting the second lower QoS data 138 during the period from T 8 to T 9 . [0077] The first and second cells are considered to be overlapped when one or more stations in the first cell can inadvertently receive packets from member stations or the access point of the other cell. The invention reduces the interference between the overlapped cells by coordinating the timing of their respective transmissions, while maintaining the TCMA protocol's preference for the transmission of high QoS data over low QoS data in each respective cell. [0078] During the operation of two overlapped cells, the method in FIG. 1A transmits a first beacon packet 124 including the intra-cell contention-free period value (the increment to the NAV) and inter-cell contention-free period value (the CFTR), from the first access point 152 to the first member stations 154 B and 154 A in the first cell 150 . The beacon packet is received by the member stations of the first cell and inadvertently by at least one overlapped member station 106 of the second cell 100 . Each member station 154 B and 154 A in the first cell increments its NAV with the intra-cell contention-free period value P 3 and stores the inter-cell contention-free period value P 4 as the CFTR. [0079] In accordance with the invention, each station that receives the first beacon packet 124 , immediately responds by transmitting a first contention-free time response (CFTR packet 126 in FIG. 1B that contains a copy of the inter-cell contention-free period P 4 value (CFTR). A CFTR packet 126 is transmitted from the first member stations 154 B and 154 A in the first cell 150 and also by the overlapped member stations 106 of the second cell 100 . The effect of the transmission of CFTR packets 126 from member stations 106 in the second cell 100 is to alert the second access point 102 and the second member stations 104 A and 104 B in the second cell 100 , that the medium has been seized by the first access point 152 in the first cell 150 . When the second access point 102 in the second cell 100 receives the CFTR packet 126 it stores a copy of the inter-cell contention-free period value P 4 as the IBNAV. [0080] Similar to a station's Network Allocation Vector (NAV), an IBNAV is set at the access point to indicate the time the medium will be free again. Also similar to the NAV, the IBNAV is decremented with each succeeding slot, similar to the decrementing of other backoff times. When the second access point receives a new IBNAV representing the first cell's contention-free period value, then the second access point must respect the IBNAV value and delay transmitting its beacon packet and the exchange of other packets in the second cell until the expiration of the received, IBNAV. [0081] Later, as shown in FIG. 1E , when the second access point 102 transmits its second beacon packet 120 including its second contention-free period values of NAV (P 6 ) and IBNAV (P 7 ), to the second member stations 104 A, 104 B and 106 in the second cell 100 , each station that receives the second beacon packet, immediately responds by transmitting a second contention-free time response (CFTR) packet 122 in FIG. 1F , that contains a copy of the second inter-cell contention-free period value P 7 . A CFTR packet 122 is transmitted from the second member stations 104 A, 104 B and overlapped station 106 in the second cell and also by the overlapped member stations of the first cell. The effect of the transmission of CFTR packets from overlapped member station 106 is to alert the first access point 152 and the first member stations 145 A and 154 B in the first cell 150 , that the medium has been seized by the second access point 102 in the second cell 100 . When the first access point 152 in the first cell 150 receives the CFTR packet 122 it stores the a copy of the second inter-cell contention-free period value P 7 as an IBNAV, to indicate the time the medium will be free again. The IBNAV is decremented with each succeeding slot, similar to the decrementing of other backoff times. [0082] The second member stations 104 A, 104 B, and 106 in the second cell 100 wait for completion of the countdown of their NAVs to begin the TCMA protocol of counting down the second shorter backoff for high QoS data and then transmitting second high QoS data packets, as shown in FIGS. 1G and 1H . [0083] Meanwhile, the first access point 152 in the first cell 150 waits for completion of the countdown of the second inter-cell contention-free period P 7 in its IBNAV in FIGS. 1G and 1H before starting the countdown of its own NAV for its own intra-cell contention-free period. The first member stations 154 A and 154 B in the first cell 150 wait for the countdown of their NAVs, to begin the TCMA protocol of counting down the first longer backoff for low QoS data and then transmitting first low QoS data in FIG. 1I . [0084] Meanwhile the second member stations 104 A, 104 B, and 106 are waiting for the TCMA protocol of counting down the second longer backoff for lower QoS data before transmitting the second lower QoS data 138 in FIG. 1J . [0085] In this manner, interference in a medium between overlapping wireless LAN cells is reduced. DETAILED DESCRIPTION OF THE INVENTION [0086] TCMA can accommodate co-existing Extended Distributed Coordination Function (E-DCF) and centralized access protocols. In order to ensure that the centralized access protocol operating under Hybrid Coordination Function (HCF) is assigned top priority access, it must have the shortest arbitration time. Its arbitration time is determined by considering two additional requirements: uninterrupted control of the channel for the duration of the contention-free period, and backward compatibility. Uninterrupted Contention-Free Channel Control [0087] The channel must remain under the control of the centralized access protocol until the contention-free period is complete once it has been seized by the centralized access protocol. For this, it is sufficient that the maximum spacing between consecutive transmissions exchanged in the centralized access protocol, referred to as the central coordination time (CCT), be shorter than the time the channel must be idle before a station attempts a contention-based transmission following the end of a busy-channel time interval. The centralized access protocol has a CCT equal to the Priority Interframe Space (PIFS). Hence, no station may access the channel by contention, using either the distributed coordination function (DCF) or Extended-DCF (E-DCF) access procedure, before an idle period of length of the DCF Interframe Space (DIFS) equaling PIFS+1 (slot time) following the end of a busy-channel time interval. This requirement is met by DCF. For E-DCF, it would be sufficient for the Urgency Arbitration Time (UAT) of a class j, UAT j , to be greater than PIFS for all classes j>1. Backward Compatibility [0088] Backward compatibility relates to the priority treatment of traffic handled by enhanced stations (ESTAs) as compared to legacy stations (STAs). In addition to traffic class differentiation, the ESTAs must provide certain traffic classes with higher or equal priority access than that provided by the STAs. That means that certain traffic classes should be assigned a shorter arbitration times than DIFS, the de facto arbitration time of legacy stations. [0089] Because the time in which the “clear channel assessment” (CCA) function can be completed is set at the minimum attainable for the IEEE 802.11 physical layer (PHY) specification, the arbitration times of any two classes of different priority would have to be separated by at least one “time slot”. This requirement implies that the highest priority traffic class would be required to have an arbitration time equal to DIFS-1(slot time)=PIFS. [0090] Though an arbitration time of PIFS appears to fail meeting the requirement for uninterrupted control of the channel during the contention-free period, it is possible for an ESTA to access the channel by E-DCF using an arbitration time of PIFS and, of the same time, allow priority access to the centralized access protocol at PIFS. This is achieved as follows. Contention-based transmission is restricted to occur after a DIFS idle period following the end of a busy channel period by ensuring that the backoff value of such stations is drawn from a random distribution with lower bound that is at least 1. Given that all backlogged stations resume backoff countdown after a busy-channel interval with a residual backoff of at least 1, an ESTA will attempt transmission following completion of the busy interval only after an idle period equal to PIFS+1(slot time)=DIFS. This enables the centralized access protocol to maintain control of the channel without colliding with contention-based transmissions by ESTAs attempting to access the channel using E-DCF. [0091] To see that the residual backoff value of a backlogged station will be greater than or equal to 1 whenever countdown is resumed at the end of a busy channel period, consider a station with a backoff value m>0. The station will decrease its residual backoff value by 1 following each time slot during which the channel remains idle. If m reaches 0 before countdown is interrupted by a transmission, the station will attempt transmission. The transmission will either fail, leading to a new backoff being drawn, or succeed. Therefore, countdown will be resumed after the busy-channel period ends, only with a residual backoff of 1 or greater. Consequently, if the smallest random backoff that can be drawn is 1 or greater, an ESTA will always wait for at least a DIFS idle interval following a busy period before it attempts transmission. [0092] Only one class can be derived with priority above legacy through differentiation by arbitration time alone, by using the arbitration time of PIFS. Multiple classes with that priority can be obtained by differentiation through other parameters, such as the parameters of the backoff time distribution; e.g. the contention window size. For all the classes so derived, a DIFS idle period will follow a busy channel interval before the ESTA seizes the channel if the restriction is imposed that the backoff value of such stations be drawn from a random distribution with lower bound of at least 1. [0093] Because PIFS is shorter than DIFS, the traffic classes with arbitration time equal to PIFS will have higher access priority than the traffic classes with arbitration time equal to DIFS. As seen in FIG. 1 , which depicts the tiered contention mechanism, a station cannot engage in backoff countdown until the completion of an idle period of length equal to its arbitration time. Therefore, a legacy station will be unable to resume backoff countdown at the end of a busy-channel interval, if an ESTA with arbitration time of PIFS has a residual backoff of 1. Moreover, a legacy station will be unable to transmit until all higher-priority ESTAs with residual backoff of 1 have transmitted. Only legacy stations that draw a backoff value of 0 will transmit after a DIFS idle period, thus competing for the channel with the higher priority stations. This occurs only with a probability less than 3 percent, since the probability of drawing a random backoff of 0 from the range [0, 31] is equal to 1/32. Top Priority for the Centralized Access Protocol [0094] For the centralized access protocol to enjoy the highest priority access, it must have an arbitration time shorter than PIFS by at least a time slot; that is, its arbitration time must equal PIFS-1 (slot time)=the Short Interframe Space (SIFS). As in the case of the highest traffic priority classes for ESTAs accessing the channel by E-DCF, the random backoff values for the beacon of the centralized access protocol must be drawn from a range with a lower bound of at least 1. Using the same reasoning as above, the centralized access protocol will not transmit before an idle period less than PIFS=SIFS+1 (slot time), thus respecting the inter-frame spacing requirement for a SIFS idle period within frame exchange sequences. Consequently, the shorter arbitration time assigned to the centralized access protocol ensures that it accesses the channel with higher priority than any station attempting, contention-based access through E-DCF, while at the same time respecting the SITS spacing requirement. [0095] It should be noted that while collisions are prevented between frame exchanges during the contention-free period, collisions are possible both between the beacons of centralized access protocols of different BSSs located within interfering range [having coverage overlap], and between the beacon of a centralized access protocol and stations accessing the channel by contention using E-DCF. The probability of such collisions is low because higher priority nodes with residual backoff value m equal to 1 always seize the channel before lower priority nodes. Inter-access point collisions are resolved through the backoff procedure of TCMA. Inter-Access Point Contention [0096] Potential collisions between BSSs engaged in centralized access can be averted or resolved by a backoff procedure. The complication arising here is that a random backoff delay could result in idle periods longer periods than the SIFS+1(slot time)=PIFS, which is what ensures priority access to the centralized protocol over E-DCF traffic contention-based traffic. Hence, the collisions with contention-based traffic would occur. Using short backoff windows in order to avoid this problem would increase the collisions experienced. In accordance with the invention, deterministically set backoff delays are used, which tend to reduce the length of the idle periods. [0097] Another aspect of inter-BSS interference that affects the performance of centralized protocols adversely is the possible interruption with a collision of what starts as an interference-free poll/response exchange between the access point and its associated stations. The possibility of coincident or overlapping contention-free periods between neighboring BSSs is eliminated through the use of an “interference sensing” method employing a new frame. Deterministic Backoff Procedure for the Centralized Access Protocol [0098] A modified backoff procedure is pursued for the beacons of the centralized access protocols. A backoff counter is employed in the same way as in TCMA. But while the backoff delay in TCMA is selected randomly from a contention window, in the case of the centralized access protocol beacons, the backoff value is set deterministically. [0099] Scheduling of packet transmission occurs once per frame, at the beginning of the frame. Only the packets queued at the start of a frame will be transmitted in that frame. It is assumed that BSSs are synchronized. A means for achieving such synchronization is through the exchange of messages relayed by boundary stations [stations in the overlapping regions of neighboring BSSs]. [0100] The backoff delay is selected through a mechanism called “tag scheduling”. Tags, which are ordinal labels, are assigned to different BSSs. BSSs that do not interfere with one another may be assigned the same tag, while BSSs with the potential to interfere with one another must receive different tags. For each frame, the tags are ordered in a way that is known a priori. This order represents the sequence in which the BSS with a given tag will access the channel in that frame. The backoff delay increases with the rank of the “tag” that has been assigned to the BSS for the current frame, as tags are permuted to give each group of BSS with the same tag a fair chance at the channel. For instance, a cyclic permutation for three tags, t=1, 2, 3, would give the following ordering: 1, 2, 3 for the first frame, 3, 1, 2 next, and then 2, 3, 1. One could also use other permutation mechanisms that are adaptive to traffic conditions and traffic priorities. The difference in the backoff delays corresponding to two consecutive tags is one time slot. FIG. 2 illustrates the ordering of transmissions from three groups of BSSs. [0101] A backoff counter is associated with each backoff delay. It is decreased according to the rules of TCMA using the arbitration time of Short Interframe Space (SIFS) as described in the preceding section. That is, once the channel is idle for a time interval equal to SIFS, the backoff counter associated with the centralized protocol of the BSS is decreased by 1 for each slot time the channel is idle. Access attempt occurs when the backoff counter expires. The minimum backoff counter associated with the highest-ranking tag is 1. FIG. 3 illustrates how three interfering BSSs share the same channel for two consecutive frames. The tags assigned in each of the two frames are (1, 2), (2, 3), and (3, 1) for the three BSSs, respectively. The backoff delays for the three tags are 1, 2, and 3 time slots. [0102] When the channel is seized by the centralized protocol of a BSS, it engages in the polling and transmission functions for a time interval, known as the contention-free period. Once the channel has been successfully accessed that way, protection by the Network Allocation Vector (NAV) prevents interference from contention based traffic originating within that BSS. Avoidance of interference from neighboring BSS is discussed below. A maximum limit is imposed on the reservation length in order to even out the load on the channel from different BSSs and allow sufficient channel time for contention-based traffic. [0103] It is important to note the advantage of using deterministic backoff delays, versus random. Assuming an efficient (i.e., compact) tag re-use plan, deterministic backoff delays increase the likelihood that a beacon will occur precisely after an idle period of length SIFS+1=PIFS. This will enable the centralized protocol to gain access to the channel, as a higher priority class should, before contention-based traffic can access the channel at DIFS=PIFS+1. Using a random backoff delay instead might impose a longer idle period and hence, give rise to collisions with contention-based traffic. Use of short backoff windows to avoid this problem would be ill advised, since that would result in collision between the various BSS beacons. [0104] Though the backoff delays are set in a deterministic manner, there are no guarantees that collisions will always be avoided. Unless the duration of the contention-free period is the same for all BSSs, there is the possibility that interfering BSSs will attempt to access the channel at once. In case of such a collision, the backoff procedure starts again with the backoff delay associated with the tag assigned to the BSS, decreased by 1, and can be repeated until expiration of the frame. At the start of a new frame, a new tag is assigned to the BSS according to the pre-specified sequence, and the deferral time interval associated with the new tag is used. [0105] Collisions are also possible if tag assignments are imperfect (interfering BSSs are assigned the same tag). In the event of such a collision, transmission should be retried with random backoff. In order to deal with either type of collision, resolution occurs by drawing a random delay from a contention window size that increases with the deterministic backoff delay associated with the tag in that frame. Though random backoff is used in this event, starting with deterministic backoff helps reduce contention time. [0106] In a hybrid scenario, random backoff can be combined with tag scheduling. Instead of using backoff delays linked to the rank of a tag in a frame, the contention window size from which the backoff delay is drawn would increase with decreasing rank. The advantage of such an approach is to relax the restrictions on re-use by allowing the possibility that potentially interfering stations will be assigned the same tag. The disadvantage is that the Inter-BSS Contention Period (IBCP) time needed to eliminate contention by E-DCF traffic increases. Interference Sensing [0107] Interference sensing is the mechanism by which the occupancy status of a channel is determined. The access point only needs to know of channel activity in interfering BSSs. The best interference sensing mechanism is one that ensures that the channel is not used simultaneously by potentially interfering users. This involves listening to the channel by both the access point and stations. If the access point atone checks whether the channel is idle, the result does not convey adequate information on the potential for interference at a receiving station, nor does it address the problem of interference caused to others by the transmission, as an access point may not be able to hear transmissions from its neighboring access points, yet there is potential of interference to stations on the boundary of neighboring BSSs. Stations must detect neighboring BSS beacons and forward the information to their associated access point. However, transmission of this information by a station would cause interference within the neighboring BSS. [0108] In order to enable communication of channel occupancy information to neighboring access points, the invention includes the following mechanism. When a beacon packet is transmitted, and before transmission of any other data or polling packets, all stations hearing the beacon will respond by sending a frame, the contention-free time response (CFTR), that will contain the duration of the contention-free period found in the beacon. An access point in neighboring BSSs, or stations attempting contention-based channel access, that receive this message from a station in the BSS overlapping region are thus alerted that the channel has been seized by a BSS. Similar to a station's Network Allocation Vector (NAV), an Inter-Cell Network Allocation Vector, also referred to herein as an inter-BSS NAV (IBNAV), is set at the access point, accordingly, indicating the time the channel will be free again. Unless the IBNAV is reset, the access point will decrease its backoff value only after the expiration of the IBNAV, according to the backoff countdown rules. [0109] Alternatively, if beacons are sent at fixed time increments, receipt of the contention-free time response (CFTR) frame would suffice to extend the IBNAV. The alternative would be convenient in order to obviate the need for full decoding of the CFTR frame. It is necessary, however, that the frame type of CFTR be recognizable. [0110] Contention by E-DCF traffic white various interfering BSSs attempt to initiate their contention-free period can be lessened by adjusting the session length used to update the NAV and IBNAV. The contention-free period length is increased by a period Inter-BSS Contention Period (IBCP) during which the access points only will attempt access of the channel using the backoff procedure, while ESTAs wait for its expiration before attempting transmission. This mechanism can reduce the contention seen by the centralized protocols when employing either type of backoff delay, random or deterministic. With deterministic backoff delays, IBCP is set equal to the longest residual backoff delay possible, which is T(slot time), where T is the number of different tags. Given reasonable re-use of the tags, the channel time devoted to the IBCP would be less with deterministic backoff delays, as compared to the random. QoS Management [0111] A QoS-capable centralized protocol will have traffic with different time delay requirements queued in different priority buffers. Delay-sensitive traffic will be sent first, followed by traffic with lower priority. Tag scheduling is used again, but now there are two or more backoff values associated with each tag, a shorter value for the higher priority traffic and longer ones for lower priority. A BSS will transmit its top priority packets first, as described before. Once the top priority traffic has been transmitted, there would be further delay before the BSS would attempt to transmit lower priority traffic in order to give neighboring BSSs a chance to transmit their top priority packets. As long as any of the deferral rime intervals for low-priority traffic is longer than the deferral time intervals for higher priority traffic of any tag, in general all neighboring BSSs would have a chance to transmit all pending top-priority packets before any lower-priority packets are transmitted. [0112] FIG. 4 illustrates how three interfering BSSs, each with two types of traffic of different priorities, share the same channel in two consecutive frames. As before, the tags assigned in each of the two frames are (1, 2), (2, 3), and (3, 1) for the three BSSs, respectively. The deferral times for the top priority traffic are 1, 2, and 3 time slots for tags 1, 2, and 3, respectively. The deferral times for the higher priority traffic are 4, 5, and 6 time slots for tags 1, 2, and 3, respectively. Tag Assignments [0113] A requirement in assigning tags to BSS is that distinct tags must be given to user entities with potential to interfere. This is not a difficult requirement to meet. In the absence of any information, a different tag could be assigned to each user entity. In that case, non-interfering cells will use the channel simultaneously even though they have different tags. Interference sensing will enable reuse of the channel by non-interfering BSSs that have been assigned different tags. [0114] There are advantages, however, in reducing the number of different tags. For instance, if the interference relationships between user entities are known, it is advantageous to assign the same tag to non-interfering BSS, and thus have a smaller number of tags. The utilization of bandwidth, and hence total throughput, would be greater as shorter deferral time intervals leave more of the frame time available for transmission. Moreover, an efficient (i.e., compact) tag re-use plan will decrease the likelihood of contention between the centralized protocol beacons of interfering BSSs contenting for access and E-DCF traffic. This problem is mitigated by using the IBCP time in the IBNAV, but re-use will reduce the length of this time. [0115] The assignment of tags to cells can be done without knowledge of the location of the access points and/or the stations. Tag assignment, like channel selection can be done at the time of installation. And again, like dynamic channel selection, it can be selected by the access point dynamically. RF planning, which processes signal-strength measurements can establish re-use groups and thus reduce the required number of tags. FIG. 5 , which includes FIGS. 5( a ) and 5( b ) , illustrates the possible re-use of tags. In FIG. 5( a ) , the access points are located at ideal spots on a hexagonal grid to achieve a regular tessellating pattern. In FIG. 5( b ) , the access points have been placed as convenient and tags are assigned to avoid overlap. Imperfect tag assignments will lead to collisions between the access points, but such collisions can be resolved. [0116] To recap, arbitration times have been assigned to a centralized access protocol that co-exists with ESTAs accessing the channel through E-DCF. The centralized access protocol has the top priority, while E-DCF can offer traffic classes with priority access both above and below that provided by legacy stations using DCF. [0117] Table 1 illustrates the parameter specification for K+1 different classes according to the requirements given above. The centralized access protocol is assigned the highest priority classification, and hence the shortest arbitration time. The top k−1 traffic classes for the E-DCF have priority above legacy but below the centralized access protocol; they achieve differentiation through the variation of the contention window size as well as other parameters. E-DCF traffic classes with priority above legacy have a lower bound, rLower, of the distribution from which backoff values are drawn that is equal to 1 or greater. Differentiation for classes with priority below legacy is achieved by increasing arbitration times; the lower bound of the random backoff distribution can be 0. [0118] BSSs within interfering range of one another compete for the channel through a deterministic backoff procedure employing tag scheduling, which rotates the backoff value for fairness among potentially interfering BSS. Re-use of a tag is permitted in non-interfering BSS. Multiple queues with their own backoff values enable prioritization of different QoS traffic classes. Contention-Free Bursts [0119] In accordance with the invention, potential collisions between different BSSs engaged in centralized access can be averted/resolved by deterministic backoff delays, which avoid collisions between access points, and eliminate gaps between consecutive poll/response exchanges between the access point and its associated stations. These are referred to as contention-free bursts (CFBs). Deterministic Backoff Procedure for the Centralized Access Protocol [0120] A modified backoff procedure is pursued for the beacons of the centralized access protocols. A backoff counter is employed in the same way as in TCMA. But while the backoff delay in TCMA is selected randomly from a contention window, in the case of the centralized access protocol beacons, the backoff value is set deterministically to a fixed value Bkoff, at the end of its contention-free session. Post-backoff is turned on. [0121] The backoff counter is decreased according to the rules of TCMA using the arbitration time AIFS=SIFS as described in the preceding section. That is, once the channel is idle for a time interval equal to SIFS, the backoff counter associated with the centralized protocol of the BSS is decreased by 1 for each slot time the channel is idle. Access attempt occurs when the backoff counter expires. An HC will restart its backoff after completing its transmission. The deterministic post-backoff procedure is illustrated in FIG. 6 . [0122] When the channel is seized by the centralized protocol of a BSS, it engages in the polling and transmission functions for a time interval, known as the contention-free period. Once the channel has been successfully accessed that way, protection by the NAV prevents interference from contention based traffic originating in the BSS. Avoidance of interference from neighboring BSS is discussed below. Non-Conflicting Contiguous Sequences of CFBs [0123] As long as the value of Bkoff is greater than or equal to the maximum number of interfering BSS, it is possible for the contention-free periods of a cluster of neighboring/overlapping BSSs to repeat in the same order without a collision between them. CFBs of different BSSs can be made to follow one another in a contiguous sequence, thus maximizing access of the centralized protocol to the channel. This can be seen as follows. [0124] Given a sequence of successful CFBs initiated by different BSSs, subsequent CFBs will not conflict because the follower's backoff counter always exceeds that of the leader by at least 1. If the previous CFBs were contiguous (that is, if consecutive CFBs were separated by idle gaps of length PIFS, the new CFBs will be also continuous because the follower's backoff delay exceeds that of the leader by exactly 1. Channel access attempts by E-DCF stations require an idle gap of length equal to DIFS or greater. FIG. 7 shows the relationships of repeating sequences of CFBs. [0125] In order to maintain contiguity, an HC that does not have any traffic to transmit when its backoff expires, it will transmit a short packet—a “peg”—and then engage in post-backoff. This way no gaps of length DIFS+1 are left idle until all HCs have completed one CFB per cycle, and restarted the backoff countdown procedure. E-DCF stations are thus prevented from seizing the channel until each BSS completes at least one CFB per cycle. FIG. 8 illustrates the role of pegging in a sequence of CFBs by three overlapping access points. [0126] Finally it is shown how such a contiguous sequence can constructed by analyzing how a new access point initiates its first CFB. Every time a new access point is installed, it must find its position in the repeating sequence of CFBs. The new access point listens to the channel for the desired cycle, trying to recognize the sequence. It listens for an “idle” PIFS following a busy channel. When that occurs, or after counting Bkoff time slots, whichever comes first, the new access point starts looking for the first idle longer than PIFS, which signifies the end of the sequence of CFBs. As long as the Bkoff is greater than the number of interfering BSS, there will always be such an idle period. The access point sets its post-backoff delay so that it transmits always right at the end of the CFB sequence. That is if at time t, an idle>PIFS has been detected, the access point's backoff at time t is Bkoff−x(t), where x(t) is the number of idle time slots after PIFS. FIG. 9 illustrates this start-up procedure for a new access point, HC 2 , given an existing access point, HC 1 . Interference Sensing [0127] Interference sensing is the mechanism by which the occupancy status of a channel is determined. The access point only needs to know of channel activity in interfering BSSs. The best interference sensing mechanism is one that ensures that the channel is not used simultaneously by potentially interfering users. This involves listening to the channel, by both the access point and stations. If the access point alone checks whether the channel is idle, the result does not convey adequate information on the potential for interference at a receiving station, nor does it address the problem of interference caused to others by the transmission, as an access point may not be able to hear transmissions from its neighboring access points, yet there is potential of interference to stations on the boundary of neighboring BSS. Stations must detect neighboring BSS beacons and forward the information to their associated access point. However, transmission of this information by a station would cause interference within the neighboring BSS. [0128] In order to enable communication of channel occupancy information to neighboring access points, the following mechanism is proposed. When a beacon packet is transmitted, and before transmission of any other data or polling packets, all stations not associated with the access point that hear the beacon will respond by sending a frame, the contention-free time response (CFTR), that will contain the duration of the contention-free period found in the beacon. An associated station will transmit the remaining duration of the contention-free period when polled. An access point in neighboring BSSs, or stations attempting contention-based channel access, that receive this message from a station in the BSS overlapping region are thus be alerted that the channel has been seized by a BSS. Similar to a station's NAV, an inter-BSS NAV (IBNAV) will be set at the access point accordingly indicating the time the channel will be free again. Unless the IBNAV is reset, the access point will decrease its backoff value only after the expiration of the IBNAV, according to the backoff countdown rules. [0129] Alternatively, if beacons are sent at fixed time increments, receipt of the CFTR frame would suffice to extend the IBNAV. The alternative would be convenient in order to obviate the need for full decoding of the CFTR frame. It is necessary, however, that the frame type of CFTR be recognizable. [0130] Contention by E-DCF traffic while various interfering BSSs attempt to initiate their contention-free period can be lessened by adjusting the session length used to update the NAV and IBNAV. The contention-free period length is increased by a period IBCP (inter-BSS contention period) during which the access points only will attempt access of the channel using the backoff procedure, while ESTAs wait for its expiration before attempting transmission. This mechanism can reduce the contention seen by the centralized protocols when employing either type of backoff delay—random or deterministic. QoS Management [0131] A QoS-capable centralized protocol will have traffic with different time delay requirements queued in different priority buffers. Delay-sensitive traffic will be sent first, followed by traffic with lower priority. A BSS will schedule transmissions from separate queues so that the QoS requirements are met. It will transmit its top priority packets first, as described before. Once the top priority traffic has been transmitted, the BSS would attempt to transmit lower priority traffic in the CFBs allotted. Three parameters are employed to help manage QoS, the deterministic backoff delay, Bkoff, and the maximum length of a CFB and of a DCF transmission. Since these parameters determine the relative allocation of the channel time between the centralized and distributed protocols, they can be adjusted to reflect the distribution of the traffic load between the two protocols. It must be kept in mind, however, that the same value of Bkoff should be used by all interfering BSSs. QoS Guarantees [0132] To enable high priority traffic to be delivered within guaranteed latency limits, a variation of the above method is described. CFBs of an access point are separated into two types, or tiers. The first contains time sensitive data and is sent when the period TXdt expires. The second tier contains time non-sensitive traffic and is sent when the backoff counter expires as a result of the countdown procedure. When all neighboring BSS have a chance to transmit their time sensitive traffic, the channel is available for additional transmissions before needing to transmit time-sensitive traffic again. Lower priority contention-free data can be then transmitted, using a backoff-based procedure. [0133] Tier II CFBs can be initiated in various methods. Two will be described here. They are: (1) random post-backoff, and (2) deterministic post-backoff. Both methods use the same AIFS used for top-priority EDCF transmissions, in order to avoid conflict with Tier I CFBs (i.e. an AIFS=PIFS). Conflict with top priority EDCF transmissions can be mitigated in case (1) or prevented in case (2) through the use of the IBNAV with an IBCP. [0134] Random post-backoff assigns an access point a backoff drawn from a prespecified contention window. A short contention window would lead to conflicts between Tier II CFBs. A long contention window reduces the conflict between interfering BSS attempting to access the channel at once. Long backoff values would reduce the fraction of the time the channel carries CFBs. Furthermore, the gaps created by multiple consecutive idle slots make room for DCF transmissions, reducing further the channel time available to CFBs. A long IBCP value would alleviate some of the conflict with DCF transmissions. [0135] Deterministic post-backoff eliminates the problems present with random post-backoff. Conflicts with top priority EDCF transmissions can be prevented with an IBCP of 1. Moreover, as explained above, the Tier II CFBs generated by this method, do not conflict with one another and form contiguous repeating sequences. Non-Conflicting Contiguous Sequences of Tier I CFBs [0136] Periodic transmission is achieved by maintaining a timer which is reset at the desired period TXdt as soon as the timer expires. A CFB is initiated upon expiration of the timer. As long as Tier I contention-free periods are all made the same size (by adding time non-critical traffic), which is not less than the maximum DCF transmission or Tier II CFB length, it is possible for the contention-free periods of a cluster of neighboring/overlapping BSSs to repeat in the same order without a collision between them. CFBs of different BSSs can be made to follow one another in a contiguous sequence, thus maximizing access of the centralized protocol to the channel. This can be seen as follows. [0137] Given a sequence of successful CFBs initiated by different BSSs, subsequent CFBs will not conflict because their timers will expire at least TICFBLength apart. If the leading access point's timer expires while the channel is busy, it will be able to start a new CFB before the follower HC because DCF transmissions are of equal or shorter length, and Type II CFBs have equal or shorter length. [0138] If the previous CFBs were contiguous (that is, if consecutive CFBs were separated by idle gaps of length PIFS), the new CFBs will be also continuous because the follower's timer will expire on or before the completion of the leader's CFB because their CFBs have the same length. Channel access attempts by E-DCF stations or Tier II CFBs require an idle gap of length equal to DIPS or greater, and hence they cannot be interjected. FIG. 10 shows the relationship of repeating sequences of Tier I CFBs. [0139] Finally it is shown how such a contiguous sequence can constructed by analyzing how a new access point initiates its first Tier I CFB. Every time a new access point is installed, it musts find its position in the repeating sequence of CFBs. The new access point listens to the channel for the desired cycle, trying to recognize the sequence. It listens for an “idle” PIFS following a busy channel. When that occurs, or after a period TXdt, whichever comes first, the new access, point starts looking for the first idle longer than PIFS, which signifies the end of the sequence of Tier I CFBs. As long as the TXdt is greater than the number of interfering BSS times the duration of a Tier I CFB, TICFBLength, there will always be such an idle period. The access point sets its timer so that it transmits always right at the end of the CFB sequence. That is, if at time t, an idle of length X(t)>PIFS has been detected, the access point's timer at time t is TXdt−X(t)+PIFS. FIG. 11 illustrates this start-up procedure for a new access point, HC 2 , given an existing access point, HC 1 . Possibility of Collisions [0140] Though the backoff delays are set in a deterministic manner, there are no guarantees that collisions will always be avoided. Unless all access points sense the start and end of CFBs at the same time, there is the possibility that interfering BSSs will attempt to access the channel at once. This situation arises when there is significant distance between access points, but not sufficient to eliminate interference between them. Such a situation can be alleviated through the assignment for different channels. [0141] Arbitration times are assigned to a centralized access protocol that co-exists with ESTAs accessing the channel through E-DCF. The centralized access protocol has the top priority, while E-DCF can offer traffic classes with priority access both above and below that provided by legacy stations using DCF. [0142] Table 1 illustrates the parameter specification for K+1 different classes according to the requirements given above. The centralized access protocol is assigned the highest priority classification, and hence the shortest arbitration time. The top k−1 traffic classes for the E-DCF have priority above legacy but below the centralized access protocol; they achieve differentiation through the variation of the contention window size as well as other parameters. E-DCF traffic classes with priority above legacy have a lower bound, rLower, of the distribution from which backoff values are drawn that is equal to 1 or greater. Differentiation for classes with priority below legacy is achieved by increasing arbitration times; the lower bound of the random backoff distribution can be 0. [0000] TABLE 1 TCMA Priority Class Description Priority Description Arbitration time rLower 0 Centralized access protocol SIFS >=1 I to k − I E-DCF Traffic with priority PIFS = SIFS + 1 >=1 Legacy or Centralized access (slot time) Tier II CFBs k E-DCF Legacy-equivalent traffic DIFS = SIFS + 2 0 priority (slot time) N = k + I E-DCF Traffic priority below >DIFS = SIFS + 0 to K Legacy (2 + n − k) (slot time) [0143] BSSs within short interfering range of one another can compete for and share the channel through the use of a deterministic backoff procedure employing post-backoff. Contiguous repeating sequences of contention-free periods provide the centralized protocol efficient access to the channel which is shared by E-DCF transmissions. The relative channel time allotted to the two protocols can be adjusted by tuning parameters of the protocol. Scheduling of traffic queued in multiple queues at the access point can meet QoS requirements. More stringent latency requirements can be met with a two-tiered method, which employs both a timer and post-backoff to initiate CFBs. [0144] CFB contiguity is preserved when using deterministic post-backoff or if CFBs of constant length are used whenever transmission is caused by the expiration of the TXdt timer—the Tier I approach. Contiguity is not necessarily preserved, however, if the CFBs have variable length when the Tier I approach is used. Any gaps that would arise in this case would allow contention-based transmissions to be interjected, thus risking delays and possible collisions between HCs. [0145] Because of the fixed CFB length requirement, whereas the Tier I approach delivers regularly-spaced CFBs, using it alone, without a Tier II protocol, results in inefficient utilization of the channel. The same fixed bandwidth allocation to each BSS gives rise to situations where channel time allocated for a CFB to one BSS may be left idle while another BSS is overloaded. The Tier II protocols provide for dynamic bandwidth allocation among BSSs. [0146] Various illustrative examples of the invention have been described in detail. In addition, however, many modifications and changes can be made to these examples without departing from the nature and spirit of the invention.

A method and system reduce interference between overlapping first and second wireless LAN cells in a medium. Each cell includes a respective plurality of member stations and there is at least one overlapped station occupying both cells. An inter-cell contention-free period value is assigned to a first access point station in the first cell, associated with an accessing order in the medium for member stations in the first and second cells. The access point transmits a beacon packet containing the inter-cell contention-free period value, which is intercepted at the overlapped station. The overlapped station forwards the inter-cell contention-free period value to member stations in the second cell. A second access point in the second cell can then delay transmissions by member stations in the second cell until after the inter-cell contention-free period expires.

FIELD OF THE INVENTION This invention relates to portable riding apparatus and in particular to a portable golf cart. BACKGROUND AND SUMMARY OF THE INVENTION So far as known to the inventors, golf carts are typically cumbersome and entirely motor driven vehicles that are not easily transported and do not offer any form of exercise when ridden. Golf carts are usually fairly heavy and most golf courses keep a fleet of carts available for rental by patrons of the golf course, since they are simply not readily portable. The inventors have proposed a light, portable golf riding apparatus that also in one embodiment offers optional human propulsion, in the case shown using foot driven pedals. The lightness of the apparatus is provided in part by using a tubular construction, with few, if any, panels, and portability is provided by having the apparatus formed from several sections or frameworks pivoting in relation to each other. In one embodiment, a first central section holds the power train and rear wheels, a front section holds the steering, and a third a seat for the rider. In one embodiment, the front section folds back upon the central section and the seat collapses onto the central section to make a compact and portable vehicle. Power is provided optionally by an electric motor or a free-wheeling pedal with chain attachment to the rear wheels. Further elucidation of the invention may be found in the detailed description that follows and the claims forming a part of this patent document. BRIEF DESCRIPTION OF THE DRAWINGS There will now be described a preferred embodiment of the invention, with reference to the drawings, by way of illustration, in which like numerals denote like elements and in which: FIG. 1 is a front isometric view of a portable riding apparatus according to the invention; FIG. 2 is a rear isometric view of the portable riding apparatus of FIG. 1; FIG. 3 is a top view of the portable riding apparatus of FIG. 1; FIG. 4 is a side schematic of the portable riding apparatus of FIG. 1 ready for use; FIG. 5 is a side schematic of the portable riding apparatus of FIG. 1 partially folded; and FIG. 6 is a side schematic of the portable riding apparatus of FIG. 1 fully folded. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Referring to FIGS. 1, 2 and 3 in particular there is shown a portable riding apparatus 10 according to the invention. The portable riding apparatus 10 is powered by a pedal set and an auxiliary electric motor. The pedal set is formed from pedals 12 on crank arms 14, with the crank arms being attached to opposed ends of a shaft 16 that is journalled in sleeve 18. A front sprocket 20 (best seen in FIG. 4) of conventional bicycle type design on one end of the shaft 16 engages a chain 22 the top part of which is enclosed within chain guard 24. The chain 22 runs rearward to a rear sprocket 26 that is operatively connected to a rear axle 40. As well known in the bicycle manufacturing art, it is preferable that the rear sprocket 26 be of the free wheel type such that upon discontinuation of pedalling while the vehicle is in motion, the rear wheels do not drive the pedals 12. A 12V traction type electric motor 30 best seen in FIG. 3 drives a conventional belt drive 32 that engages a grooved drive wheel 34 that is fixed on rear axle 40. Rear axle 40 connects to the left rear wheel 38L on one end and to the right rear wheel 38R at the other end. A conventional lead acid battery 42 may be used to provide power for the drive motor 30 through cable 41. The drive motor 30 is controlled by push button control 43 on steering set 46 in conventional manner through cable 48. Braking is provided by lever 44 on steering set 46 that attaches to a conventional brake on the rear axle 40. The motor 30 is normally in the off position and pushing of the button 43 activates the motor 30. The frame of the portable riding apparatus includes three main parts: a central framework that supports the driving mechanism, including pedals, motor, battery, and rear axle and wheel set; a front framework that supports the front wheels and steering mechanism and a seat framework mounted on the central section that supports a seat for a rider. The central framework and the front framework together form a body for the portable riding apparatus. The central rigid framework is formed on its right side (conventional right according to a person sitting in the vehicle and looking forward) by a right upper tube 52R that is connected on one end to the sleeve 18 at the front end of the central rigid framework and the other to a cross tube 66 adjacent the axle 40 at the rear portion of the central rigid framework. A right center tube 56R extends downward from the sleeve 18 and connects to a pivot point 58, formed of a linked pair of rods 60 and 62. A right lower tube 54R extends rearward from the pivot point 58 to and beyond the cross tube 66 adjacent the axle 40. A mirror image of the right side forms the left side to the central rigid framework, with the sleeve 18, cross tube 66 and forward connecting rod 62 connecting the left and right sides. Elements on the right side are given the reference suffix R, and like elements on the left side are given the reference suffix L. Lateral tubes 64L and 64R connect between the left and right lower tubes 54L and 54R respectively and the cross tube 66 adjacent respective rear wheels 38L and 38R. The axle 40 is supported for rotation by bearings 63L and 63R that are mounted on the left lateral tubes 64L and 64R respectively. The left lower tube 54L and right lower tube 54R together form a lower portion of the central rigid framework. A plate may extend between the left lower tube 54L and the left lateral tube 64L under the motor 30 to form a support surface for the motor 30, or the motor may be bolted directly to the tubes 54L and 64L and cross tube 66. A brace between the left lower tube 54L and right lower tube 54R is provided by tube 50. The front rigid framework is formed from a right rear tube 70R that extends between rod 60 at pivot 58 and a connector 72. The connector 72 may be formed of a tube as shown or an arcuate plate that conforms to the outside surface of the sleeve 18, and the connector 72 and sleeve 18 may be locked together with any of various suitable locking means such as a toggle clamp fastened to the connector 72 that engages a groove or lip on the sleeve 18 or with a pin (not shown) or the like that is received by loops on the connector 72 and sleeve 18. The front rigid framework pivots about the pivot 58 as shown in FIGS. 5 and 6 on release of the locking means at the sleeve 18 and is held firmly against the sleeve 18 when the locking means is engaged. The front rigid framework also includes a right lower front tube 76R extending forward from the pivot 58 to a steering frame 78. A right upper front tube 80R extends between the steering frame 78 to the connector 72. The left side of the front rigid framework is a mirror image of the right side, and together with the connector 72, rod 60 forming part of pivot 58 and steering frame 78 form a rigid section. The left lower front tube 76L and the right lower front tube 76R together form a base portion for the front rigid framework. A front wheel set is attached to the frame 78 on the front rigid framework that includes wheels 82L and 82R each pivotally attached to the frame 78 at pivots 86L and 86R respectively. Extending upward from and pivotally connected to the right rear tube 70R and left rear tube 70L at points 88R and 88L respectively (or to either side of the connector 72) is a right steering column support 92R and a left steering column support 92L. The supports 92R and 92L are pivotally attached to either side of the steering sleeve 94. A short vertical tube 100 extends vertically and rigidly from sleeve 18 and terminates in a T-bar 103 forming a pivot point. Two elbows 106L and 106R are pivotally connected to and extend from left and right sides respectively of the T-bar 103 to the sleeve 94. A collapsible steering column 96 formed of an upper part 96U and a lower part 96L having a pivot point 107 (see FIG. 5) at the point of connection of the two parts passes through the sleeve 94 to a pivot point 98 attached to the steering frame 78. As shown better in FIGS. 5 and 6, when the portable riding apparatus is set up for use, the pivot point 107 is held within the sleeve 94 and the steering column is prevented from collapsing by the sleeve 94. Left and right rods 102L and 102R respectively connect the extreme lower end 96L of the steering column 96 to steering arms 104L and 104R rigidly attached to the wheels 82L and 82R respectively. Rotation of the steering column 96 turns the wheels in known manner. The steering column 96 terminates at its upper end 96U in the steering set 46. Optionally, a shield 108 may be attached to the front rigid framework to protect the rider from spray or debris. The seat framework is formed of a rear U-shaped support 110 (not shown in FIG. 3 but see the other Figures) pivotally attached at its left and right ends to left and right brackets 111L and 111R respectively mounted on lateral tubes 64L and 64R respectively adjacent the bearings 63L and 63R of the axle 40, and a pair of arms 112L and 112R that are joined together at one end by a bar 113 whose ends are pivotally connected to the left and right upper tubes 52L and 52R respectively near the sleeve 18. The arms 112L and 112R extend upward and rearward from the pivoting bar 113 to a seat 116. The arms 112L and 112R support the seat 116 with back rest 118 attached to the ends of arms 114L and 114R. The arms 112L and 112R and arms 114L and 114R respectively connect at points 120 under the seat 116. The arms 112L and 112R are fixed to the seat 116 while the arms 114L and 114R are fixed to the back rest 118 and are pivotally connected to the points 120. In normal use the arms 114L and 114R and hence the back rest 118 may be supported by the U-shaped support 110 or, as shown, a frame 124 affixed to the seat 116. The U-shaped support 110 releasably attaches to the rear of the seat 116 using any of several known releasable fastening methods such as a U-shaped connector 117 (FIG. 4) fixed to the base of the seat or the like. The arms 112L and 112R, together with the support 110 support the seat 116 in fixed position in relation to the central framework. Each of the load bearing tubes and braces is preferably tubular, though not necessarily round, and made of lightweight and strong material such as aluminum or one of the many light alloys used in bicycle construction. The respective tubes are preferably welded together in accordance with known techniques. The supports 92L and 92R and the elbows 106L and 106R may be made of flat metal bars since they are not load bearing. The pedals are conventional bicycle pedals. The wheels are chosen for the particular purpose intended, and in the case of a golf cart may be slightly larger than conventional golf cart wheels, with a wide tread to avoid damage to the fairways. The wheels shown are 8" pneumatic tires on plastic moulded rims. The seat may be made to be adjustable in height. The portable riding apparatus is primarily intended for use as a golf cart, but has other uses. When used as a golf cart, upper supports 126 complete with conventional straps 130 may be attached to frame 124 and lower supports 128R and 128L may be attached respectively between the ends of tubes 54R, 64R and 54L, 64L at the rear of the portable riding apparatus for retaining golf bags in conventional manner. Provision may also be made for carrying refreshments. However, the portable riding apparatus has other uses, for example use by the disabled, in which case the golf bag supports may be replaced by other suitable supports, as for example groceries. The manner of operation of the riding apparatus is as follows. Removal of the clamp, pin or the like locking means holding the connector 72 to the sleeve 18 allows the front rigid framework to rotate in relation to the central rigid framework from the position shown in FIG. 4 in which the front framework is forward of the central framework through the position shown in FIG. 5 to the position shown in FIG. 6 in which the lower portion of the central framework is adjacent the base portion of the front framework. By this means the body of the portable riding apparatus is foldable about a central axis between the front and rear wheel sets that is parallel to the rear axle 40 (that is, the axis is horizontal and lateral, or perpendicular to both the forward and vertical directions). As the front section rotates under the central section, the steering column 96 slides downward in sleeve 94 until the pivot point 107 on the steering column is clear of the sleeve 94 and sliding on the steering column upper part 96U, at which point the steering column may then be collapsed about the apparatus. To accommodate this movement of the sleeve 94, the supports 92L and 92R and the elbows 106L and 106R rotate about their respective pivots 88 and 103. By release of the releasable fastener, the U-shaped support 110 may be detached from the seat 116 and rotated rearward away from the seat 116 as shown in FIG. 5. The arms 112L and 112R then rotate downward about pivot bar 113 on the tubes 52L and 52R, thus collapsing the seat from its fixed position (FIG. 4) onto or close to the central rigid framework as shown in FIGS. 5 and 6. Also as shown in FIG. 5, the support 110 may then rotate forward into the position shown in FIG. 6 in which it rests on top of the seat 116. The steering column folds about the pivot 107 as shown in FIGS. 5 and 6 to wrap around the collapsed riding apparatus. By this means, a compact portable four wheeled vehicle may be obtained, that may easily be transported in the rear of a hatchback sedan. Alternative Embodiments A person skilled in the art could make immaterial modifications to the invention described and claimed in this patent without departing from the essence of the invention.

A light, portable golf riding apparatus that may be electric motor or pedal driven. The lightness of the apparatus is provided in part by using a tubular construction, with few, if any, panels, and portability is provided by having the apparatus formed from several sections or frameworks pivoting in relation to each other. In one embodiment, a first central section holds the power train and rear wheels, a front section holds the steering column, and a third a seat for the rider. The central and front sections pivot towards each other, the seat folds onto the central section and the steering collapses about the apparatus to form a compact body.

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of priority under 35 U.S.C. §119 of German Patent DE 10 2014 213 746.2 filed Jul. 15, 2014, the entire contents of which are incorporated herein by reference. FIELD OF THE INVENTION [0002] The present invention pertains to a static mixer for an exhaust system for mixing a reducing agent with an exhaust gas flow. The present invention also pertains to an exhaust system equipped with such a mixer. BACKGROUND OF THE INVENTION [0003] In exhaust systems of internal combustion engines there is in certain applications the need to introduce a reducing agent into the exhaust gas flow. For example, a fuel can be introduced into the exhaust gas flow upstream of an oxidation catalytic converter in order to increase the heat of the exhaust gas flow due to a reaction of the fuel in the oxidation catalytic converter, for example, in order to heat up a particle filter that is arranged downstream to its regeneration temperature. It is likewise common in SCR systems to introduce an aqueous urea solution upstream of an SCR catalytic converter into the exhaust gas flow, whereby SCR denotes Selective Catalytic Reaction. The aqueous urea solution can be converted by means of thermolysis and hydrolysis into ammonia and carbon dioxide, which makes a conversion of nitrogen oxides into nitrogen and water possible in the SCR catalytic converter. [0004] In order to optimize the respective reaction, which shall be brought about with the reducing agent introduced, it is of high importance to mix the introduced reducing agent with the exhaust gas flow as homogeneously as possible. Frequently, the reducing agent is introduced in liquid form into the exhaust gas flow, such that it is also necessary to evaporate the reducing agent as completely as possible. A static mixer mentioned in the introduction, which brings about an intense mixing of exhaust gas and reducing agent, is used for this purpose. [0005] A static mixer, which has a plurality of guide blades for deflecting the exhaust gas flow, is known from EP 1 985 356 A2. For this purpose, the guide blades project into the exhaust gas flow and are set towards the exhaust gas flow in order to be able to bring about the respective deflection of the exhaust gas flow. As a result of this, the guide blades at the same time form impact areas for the reducing agent introduced in liquid form. Due to the impact of the guide blades with the exhaust gas flow, these guide blades have a relatively high temperature, such that the guide blades at the same time are used as evaporation surfaces for reducing agent deposited thereon. [0006] An as large as possible impact surface, on the one hand, and an as intensive as possible deflection of the flow, on the other hand, result each in an increased flow resistance of the mixer. The flow resistance of the mixer brings about a rise in pressure in the exhaust system upstream of the mixer, which reduces the efficiency of an internal combustion engine equipped with the exhaust system or increases its fuel consumption. SUMMARY OF THE INVENTION [0007] An object of the present invention is to provide an improved embodiment for a static mixer of the type mentioned above or for an exhaust system equipped therewith, which is characterized especially by a comparatively low flow resistance, while at the same time a sufficient mixing and especially a sufficient evaporation can be achieved. [0008] According to the invention, a static mixer is provided comprising a plurality of guide blades for deflecting the exhaust gas flow. At least one of the guide blades comprises a perforation through which the exhaust gas flows. [0009] According to another aspect of the invention, an exhaust system is provided for an internal combustion engine. The exhaust system comprises an injector for introducing a liquid reducing agent into an exhaust gas flow and at least one static mixer arranged downstream of the injector with regard to the exhaust gas flow. The static mixer comprises a plurality of guide blades for deflecting the exhaust gas flow. At least one of the guide blades comprises a perforation through which the exhaust gas flows. [0010] The present invention is based on the general idea of equipping at least one of the guide blades, and preferably all guide blades, each with a perforation, through which the exhaust gas, i.e., a part of the exhaust gas flow, can flow. It has been shown that such a perforation can significantly reduce the flow resistance of the mixer, whereby at the same time turbulence is sufficiently generated by the perforation to bring about the desired intensive mixing. [0011] In the present context, a perforation is defined as any interruption of a structure of the guide blade that is otherwise closed or impermeable to exhaust gas. Thus, openings, through holes, tiltings and the like are perforations. [0012] The perforation of the respective guide blade may in this case have a plurality of passage openings which are each arranged within a lateral outer contour of the respective guide blade according to a preferred embodiment. Thus, the respective guide blade has an outer contour which is not compromised by the passage openings. In this way, the flow-guiding function of the respective guide blades is only comparatively slightly compromised by the perforation. [0013] According to an advantageous variant, the passage openings may have a round or an angular cross section. Likewise, the passage openings may have a punctiform or else an oblong cross section. Passage openings with oblong cross section may be linear or single-curved or multi-curved. [0014] In another advantageous variant, the passage openings may each have an oblong cross section and be arranged parallel to each other and next to each other along a blade length measured from a blade footing to a blade tip of the respective guide blade. In such an embodiment, a low flow resistance can be shown for the respective guide blade with sufficient or improved mixing effect. [0015] According to a variant, the passage openings may be arranged with their oblong cross sections sloped toward the blade length and sloped toward a blade width measured from a leading edge to a discharge edge of the respective guide blade. By means of this measure, the mixing effect can, in addition, be affected and optimized. [0016] According to another embodiment, the perforation may have at least one or a plurality of passage openings, which are open on the side at a discharge edge or at a leading edge of the respective guide blade. In this embodiment, these passage openings open on the side have an effect on a lateral outer contour of the respective guide blade. For example, targeted flow separations and swirl may be generated thereby, which may have advantageous effects on an intensive mixing. All the passage openings of the perforation are preferably open on the side at the discharge edge or at the leading edge. However, an embodiment, in which the perforation has at least one open passage opening on the outer contour of the guide blade and at least one passage opening lying completely within the outer contour, is also generally conceivable. [0017] In a variant which assumes that a plurality of passage openings open on the side are provided, the passage openings open on the side may be oblong and be sloped towards a blade length of the guide blade as well as towards a blade width of the guide blade. As before, the blade length extends from a blade footing up to a blade tip, while the blade width extends from the leading edge to the discharge edge. [0018] In another variant, the passage openings open on the side of the leading edge may be sloped with regard to the blade length opposed to the passage openings of the discharge edge. As a result of this, the flow-conducting action of the guide blades can be optimized with regard to an improved mixing. [0019] In an alternative embodiment the perforation in at least one of the guide blades may be formed from a single passage opening. Such a singular passage opening is advantageously dimensioned larger in terms of its flow cross section than the individual passage openings of the perforations explained above, which are formed by a plurality of passage openings. Accordingly, such a perforation has a reduced flow resistance. [0020] This singular passage opening may be arranged within a lateral outer contour of the respective guide blade in one variant. In other words, an embodiment, in which the passage opening does not have an effect on the outer contour of the guide blade, is preferred here as well. It can essentially extend from a blade footing up to a blade tip as well. Further, the passage opening may have a pointed design, whereby the tip of the passage opening can then be arranged in the area of the blade tip. As an alternative, the passage opening may also be provided with a constant width. [0021] Basically, it is likewise possible to develop the singular passage opening open on the side on a blade tip of the respective guide blade. If this singular passage opening open on one side is, in addition, designed as oblong, quasi a division of the guide blade in the area of the passage opening can thus be achieved. Such a passage opening, open in the area of the blade tip, may lead to an especially low flow resistance in the area of the respective guide blade. [0022] In another advantageous embodiment the respective guide blade may have a single- or multi-curved course along its blade length. While the guide blades usually have a linear design, it is suggested here now to equip the respective guide blade with a curved course with regard to its central longitudinal axis. The central longitudinal axis of the respective guide blade extends thereby from the blade footing to the blade tip approximately in the center with regard to the blade width. A single-curved guide blade then has a sickle-shaped design. A twice-curved guide blade then has an S-shaped design. In addition or as an alternative, the respective guide blade may have a twisting with regard to its central longitudinal axis, which leads to a varying pitch angle along the blade length. [0023] In another advantageous embodiment, the mixer may have a cylindrical pipe body, which encloses a flow cross section through which the exhaust gas flow can flow in the circumferential direction and from which the guide blades project inwards. In this type of construction, the guide blades may be especially arranged detached radially inwards in the area of their blade tips. Furthermore, the guide blades may be arranged in a contactless manner relative to each other. [0024] Especially advantageous is a variant, in which the pipe body with all guide blades is produced from a single sheet metal body by means of shaping. As a result of this, the mixer can be produced at a comparatively low cost by means of punching and shaping processes. [0025] In another advantageous embodiment, the perforation may have at least one passage opening with an opening edge, which is detached along its entire circulation. Such a detached opening edge may be produced by a punching process in an especially simple manner in case of a guide blade designed as a sheet metal body. Preferably, the circulation is completely closed, when the respective passage opening is arranged within the outer contour of the guide blade. If, on the other hand, the passage opening is designed open on the side on the outer contour of the guide blade, the circulation of the opening edge on the outer contour is interrupted. [0026] Advantageously, all passage openings of the respective guide blade are equipped with such a detached opening edge. [0027] In another embodiment, the perforation may have at least one passage opening with an opening edge, which is connected with a tilting device (angled feature) along a circulation section. The tilting device may at least partly cover the associated passage opening. In addition or as an alternative, the tilting device may be sloped towards an area of the guide blade adjacent thereto. In addition or as an alternative, the tilting device may be arranged at least partly offset towards an area of the guide blade adjacent thereto. The arrangement of the tilting device is thereby preferred, such that the tilting device at least partly covers the passage opening and accordingly brings about a flow deflection of an exhaust gas flow passing through the passage opening. Such a tilting device at the opening edge of the passage opening improves the mixing action of the guide blade. At the same time, the flow resistance can be reduced by the flow deflection with the tilting device. [0028] The tilting device is advantageously formed integrally in one piece with the respective guide blade. The respective tilting device can especially advantageously be an area of the respective guide blade that is free-cut and tilted for producing the respective passage opening. Thus, the respective guide blade can be equipped in an especially simple manner with the passage openings and tilting devices adjacent thereto. [0029] According to an advantageous variant, provisions may be made for at least one such tilting device to have a central area and two lateral areas, whereby the central area extends essentially parallel to the respective guide blade and is connected with the respective guide blade via the two lateral areas. As a result of this, an especially efficient covering of the respective passage opening is obtained. [0030] Further, according to another variant, provisions may be made for at least one such tilting device to be designed as a wing, which is connected only on one side with the respective guide blade and is otherwise arranged detached to the respective guide blade. Such a wing acts as a flow-guiding element, such that the flow of the respective passage opening can be especially favorably affected by means of such a wing. [0031] In addition, provisions may advantageously be made for at least one such tilting device to be formed by a step, which is spaced apart in a blade longitudinal direction from a (different) step formed in the respective guide blade. The respective step may be produced by means of bending the guide blade twice, preferably by approx. 90°, transversely to its longitudinal direction. [0032] It is clear that the different variants mentioned above for the perforation—insofar as useful—can be achieved at at least one single guide blade or in case of various guide blades of the same mixer, i.e., especially passage openings of different sizes and/or geometries and/or with or without tilting devices. [0033] The mixer presented here is heated exclusively by the exhaust gas flow during the operation of the exhaust system, such that it operates free from external energy with regard to its evaporation action. [0034] In an exhaust system according to the present invention, which is suitable for discharging combustion waste gases in an internal combustion engine, an injector is provided for introducing a liquid reducing agent into the exhaust gas flow, whereby, in addition, at least one mixer of the type described above is arranged downstream of this injector with regard to the exhaust gas flow. The exhaust system may, furthermore, have an SCR catalytic converter downstream of the mixer or an oxidation catalytic converter downstream of the mixer. [0035] Further important features and advantages of the present invention appear from the subclaims, from the drawings and from the associated description of the figures based on the drawings. [0036] It is apparent that the features mentioned above and those still to be explained below can be used not only in the respective given combination, but also in other combinations or alone, without going beyond the scope of the present invention. [0037] Preferred exemplary embodiments of the present invention are shown in the drawings and are explained in detail in the following description, whereby identical reference numbers refer to identical or similar or functionally identical components. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated. BRIEF DESCRIPTION OF THE DRAWINGS [0038] FIG. 1 is a circuit-diagram-like schematic diagram of an internal combustion engine with an exhaust system, which contains a static mixer; [0039] FIG. 2 is an isometric view of the mixer; [0040] FIG. 3 is an axial view of the mixer; [0041] FIG. 4 is a layout of the mixer; [0042] FIG. 5 is a simplified view of a guide blade of the mixer in one of various embodiments; [0043] FIG. 6 is a simplified view of a guide blade of the mixer in another of various embodiments; [0044] FIG. 7 is a simplified view of a guide blade of the mixer in another of various embodiments; [0045] FIG. 8 is a simplified view of a guide blade of the mixer in another of various embodiments; [0046] FIG. 9 is a simplified view of a guide blade of the mixer in another of various embodiments; [0047] FIG. 10 is a simplified view of a guide blade of the mixer in another of various embodiments; [0048] FIG. 11 is a simplified view of a guide blade of the mixer in another of various embodiments; [0049] FIG. 12 is a simplified view of a guide blade of the mixer in another of various embodiments; [0050] FIG. 13 is a simplified view of a guide blade of the mixer in another of various embodiments; [0051] FIG. 14 is a simplified view of a guide blade of the mixer in one of various embodiments and partly with associated sectional view or variant A; [0052] FIG. 15 is a simplified view of a guide blade of the mixer in another of various embodiments and partly with associated sectional views or variants A, B and C; [0053] FIG. 16 is a simplified view of a guide blade of the mixer in another of various embodiments; [0054] FIG. 17A is a simplified view of another embodiment of a guide blade of the mixer; [0055] FIG. 17B is a simplified view of another embodiment of a guide blade of the mixer; [0056] FIG. 17C is a simplified view of another embodiment of a guide blade of the mixer; [0057] FIG. 17D is a simplified view of another embodiment of a guide blade of the mixer; [0058] FIG. 18 is a simplified view of a guide blade of the mixer in another of various embodiments; [0059] FIG. 19 is a simplified view of a guide blade of the mixer in another of various embodiments and partly with associated sectional views or variants A and B; and [0060] FIG. 20 is an isometric view of a guide blade of the mixer from FIG. 19 in the area of a perforation. DESCRIPTION OF THE PREFERRED EMBODIMENTS [0061] Referring to the drawings, according to FIG. 1 , an internal combustion engine 1 comprises an engine block 2 which contains a combustion chamber 4 each in a plurality of cylinders 3 . Pistons, which are not shown here, are arranged with adjustable stroke in the cylinders 3 , such that the internal combustion engine 1 is a piston engine. A fresh air feed unit 5 is provided for supplying the combustion chambers 4 with fresh air. A corresponding fresh air flow 6 is indicated by an arrow. In order to be able to discharge combustion gases from the combustion chambers 4 , the internal combustion engine is, in addition, equipped with an exhaust system 7 . An exhaust gas flow 8 is indicated by an arrow. In the example of FIG. 1 , the exhaust system 7 is equipped with an SCR system 9 , which has an injector for introducing a liquid reducing agent into the exhaust gas flow 8 , an SCR catalytic converter 11 for reducing nitrogen oxides with the aid of the previously injected reducing agent as well as a static mixer 12 . With regard to the flow direction of the exhaust gas flow 8 , the SCR catalytic converter 11 is arranged downstream of the injector 10 . Further, the mixer 12 , with regard to the direction of flow of the exhaust gas flow 8 , is arranged downstream of the injector 10 and upstream of the SCR catalytic converter 11 . The exhaust system 7 has an exhaust line 13 , into which the above-mentioned components of the SCR system 9 are integrated. [0062] According to FIGS. 2 and 3 , the mixer 2 has a plurality of guide blades 14 which are each used for deflecting the exhaust gas flow 8 . In the preferred example shown the mixer 12 has, moreover, a cylindrical pipe body 15 , which encloses a flow cross section 16 , through which the exhaust gas flow 8 can flow, in the circumferential direction 17 . The circumferential direction 17 is in reference to a central longitudinal axis 18 of the pipe body 15 or of the mixer 12 . The guide blades 14 project from the pipe body 15 inwards, i.e., in the direction of the central longitudinal axis 18 . Thereby, the direction of extension of the respective guide blade 14 has at least one radial component. Further, this direction of extension may optionally also have an axial component. [0063] Advantageously, this pipe body is produced integrally with the guide blades 14 from a single sheet metal body 19 , namely by means of shaping, such that the mixer 12 is ultimately a single shaped sheet metal part. A layout of the sheet metal body 19 or of the mixer 12 is shown in FIG. 4 . The sheet metal body 19 has a jacket section 20 , which forms the pipe body 15 in the shaped state. The guide blades 14 project from this jacket section 20 . In the layout of FIG. 4 , the individual guide blades 14 are already free-cut, whereby individual sections are designated with 21 . The sections 21 pass over at the jacket section 20 into round holes 22 to avoid a tear formation at this passing over. [0064] In order to produce the mixer 12 from the planar sheet metal body 19 in FIG. 4 , the blades 14 are each bent over a bending edge 23 and the jacket section 20 is bent over the central longitudinal axis 18 of the mixer 12 in the circumferential direction 17 . Thereby, the longitudinal ends 24 of the jacket section 20 may form a butt joint at the pipe body 15 in the circumferential direction 17 and be fastened to each other. [0065] As can be inferred from FIGS. 2 through 4 , the guide blades 14 in the example shown of the mixer 12 are exclusively designed on a leading side of the pipe body 15 . For orientation, the exhaust gas flow 8 is indicated by a flow arrow. Likewise, an embodiment is conceivable, in which all guide blades 14 are arranged on a discharge side of the pipe body 15 . Further, it is conceivable to provide such guide blades 14 at the pipe body 15 both on the leading side and on the discharge side each. The use of two mixers 12 , which are arranged one behind the other in the direction of flow of the exhaust gas flow 8 , is also conceivable. [0066] As can be inferred from FIGS. 2 through 4 , at least one of the guide blades 14 is equipped with a perforation 25 . The perforation 25 is thereby configured, such that the perforation 25 traverses the otherwise closed guide blade 14 , such that the exhaust gas flow 8 or partial flows of the exhaust gas flow 8 can flow through the guide blade 14 through the respective perforation 25 . Even though not all guide blades 14 are equipped with such a perforation 25 in the examples of FIGS. 2 through 4 , an embodiment is, however, preferred, in which all of the guide blades 14 have such a perforation 25 . Even though various perforations 25 are provided in the individual guide blades 14 in FIGS. 2 through 4 , an embodiment is preferred, in which the perforated blades 14 have an identical perforation 25 each. [0067] Various embodiments of such a perforation 25 are explained in detail below based on FIGS. 5 through 20 . For example, the respective perforation 25 may have a plurality of passage openings 26 , which are arranged within a lateral outer contour 27 of the respective guide blade 14 . FIGS. 5 through 10 , 15 and 18 show embodiments, in which all passage openings 26 of the perforation 25 are arranged within the outer contour 27 of the guide blade 14 . In the embodiment shown in FIG. 5 , all passage openings 26 are equipped with a round and punctiform cross section. In particular, the passage openings 26 show each a round cross section. [0068] In the embodiment shown in FIG. 6 , the passage openings 26 are designed as oblong and linear. Further, they extend parallel to each other. Furthermore, the parallel arranged passage openings 26 are arranged next to each other along a blade length 28 . The blade length 28 is thereby measured from a blade footing 29 up to a blade tip 30 . In a mixer according to the embodiment shown in FIGS. 2 through 4 , the blade footing is arranged at the pipe body 15 , while the blade tip 30 is arranged detached in the area of the central longitudinal axis 18 . [0069] The embodiment shown in FIG. 7 corresponds to the embodiment shown in FIG. 6 , providing that the passage openings 26 have different cross sections. On the other hand, FIG. 8 shows an embodiment, in which the oblong passage openings 26 have an angular, in this case parallelogram-like cross section. Further, the passage openings 26 are arranged sloped with regard to their oblong cross section towards the blade length 28 as well as towards a blade width 31 . The blade width 31 is thereby measured from a leading edge 32 up to a discharge edge 33 of the respective guide blade 14 . By contrast, the oblong passage openings 26 in the examples of FIGS. 6 and 7 are aligned parallel to the blade width 31 . [0070] FIG. 9 now shows an embodiment, in which a plurality of oblong passage openings 26 are arranged one behind the other in the direction of the blade width 31 , which passage openings 26 are arranged in this case, in addition, offset to each other in the direction of the blade length 28 . Further, the passage openings 26 are arranged next to each other along the blade length 28 , as well as aligned parallel to each other and parallel to the blade width 31 . In the perforation 25 shown in FIG. 9 , the passage openings 26 have markedly smaller cross sections through which flow is possible than in the embodiments of FIGS. 5 through 8 . [0071] FIG. 10 shows an embodiment, in which the passage openings 26 have an oblong cross section and thereby are single-curved. Regardless of the geometry and number of the passage openings 26 , FIG. 10 shows, in addition, an embodiment, in which the respective guide blade 14 has a twice-curved course along its blade length 28 . As a result of this, the guide blade 14 has an S-shaped course with regard to its blade length 28 . [0072] In the embodiments shown in FIGS. 11 and 16 , the respective perforation 15 has a plurality of passage openings 26 , which are open on the side on the leading edge 32 or on the discharge edge 33 of the respective guide blade 14 . As a result of this, the passage openings 26 have an effect on the lateral outer contour 27 of the guide blade 1 . In the example of FIG. 14 , all passage openings 26 of the perforation 25 are designed as open on the side. Further, all passage openings 26 are oblong in this case and provided with a rectangular cross section. In addition, the passage openings 26 arranged on the leading edge 32 are each arranged parallel to each other and next to each other with regard to the blade length 28 . The passage openings 26 provided on the discharge edge 33 are also arranged parallel to each other and next to each other in the blade length 28 . Furthermore, the passage openings 26 shown are aligned sloped both towards the blade length 28 , i.e., towards the blade width 31 . In addition, provisions are thereby made, in addition, for the passage openings 26 of the leading edge 32 to be sloped with regard to the blade length 28 opposed to the passage openings 26 of the discharge edge 33 . In particular, the passage openings 26 are arranged in a mirror-symmetrical manner with regard to a central longitudinal axis of the respective guide blade 14 , as a result of which the perforation 25 shows a sweepback and the guide blade 14 has a fishbone-like shape. The sweepback of the perforation 25 is aligned toward the blade tip 30 for this. [0073] On the other hand, only a single passage opening 26 open on the side is provided on the leading edge 32 and on the discharge edge 33 each in FIG. 16 . [0074] While the examples of FIGS. 5 through 11 , 15 , 17 and 18 each show perforations 25 , which have a plurality of passage openings 26 , FIGS. 12 through 14 and 19 , 20 show an embodiment each, in which the perforation 25 has only a single passage opening 26 each. At least in the examples of FIGS. 12 through 14 , this passage opening 26 is provided with an oblong cross section, which is aligned parallel to the blade length 28 . Furthermore, the respective passage opening 26 extends over an essential longitudinal section of the respective guide blade 14 . In these examples, the respective passage opening 26 extends over at least 75% of the blade length 28 . In the example of FIG. 12 , the passage opening 26 has a rectangular cross section, while a triangular cross section is provided in the embodiment shown in FIG. 13 . A rectangular cross section is provided again in FIG. 14 . In FIGS. 12 and 14 , the passage opening 26 has a constant cross section along the blade length 28 , while in FIG. 13 the cross section decreases in the direction toward the blade tip 30 . In the examples of FIGS. 12 through 14 and 19 , 20 , the passage opening 26 remains within the lateral outer contour 27 of the associated guide blade 14 . In another embodiment, the passage opening 26 may, on the other hand, be so arranged and/or so dimensioned that it is open on the side at the blade tip 30 , as a result of which the guide blade 14 is quasi divided in the area of this passage opening 26 . [0075] In the embodiments of FIGS. 5 through 13 , the passage openings 26 are each equipped with an opening edge 34 , which is detached along is entire circumferential extent (circulation). In the embodiments of FIGS. 5 through 10 , 12 and 13 , in which the passage openings 26 are arranged within the outer contour 27 , the respective circulation of the opening edge 24 is closed, while the circulation in the embodiment shown in FIG. 11 , in which the passage openings 26 are open on the side at the outer contour 27 , is interrupted in each case by the opening on the side of the respective passage openings 26 . [0076] In the embodiments of FIGS. 14 through 20 , the perforation 25 may have at least one passage opening 26 , whose opening edge 34 is connected with a tilting device 35 along a circulation section. In the embodiments of FIGS. 16 through 18 , this tilting device 35 is arranged sloped towards an area of the respective guide blade 14 adjacent thereto. Thereby, the respective tilting device 35 brings about a covering of at least one part of the respective passage opening 26 . In FIGS. 16 through 18 in the rectangular passage opening 26 , three consecutive, linear circulation sections each form a free opening edge 34 , while the remaining fourth, linear circulation section is then connected with the tilting device 35 , as a result of which the respective tilting device 35 forms a wing 36 . The tilting device 35 advantageously forms a free-cut and tilted area of the guide blade 14 in the creation of the respective passage opening 26 . Thus, the respective tilting device 35 is formed integrally in one piece with the guide blade 14 . [0077] In FIGS. 14 through 20 , provisions are made for the perforation 25 to have at least one passage opening 26 with an opening edge 34 , which is connected with a tilting device 35 along at least one circulation section, which tilting device 35 at least partly covers the associated passage opening 26 and/or is arranged sloped and/or offset towards an area of the guide blade 14 adjacent thereto. [0078] In FIGS. 14 and 15 , provisions are made for at least one such tilting device 35 to have a central area 36 and two lateral areas 37 , whereby the central area 36 extends essentially parallel to the respective guide blade 14 and is connected via the two lateral areas 37 with the respective guide blade 14 . [0079] On the other hand, in FIGS. 17 and 18 , provisions are made for at least one such tilting device 35 to be designed as a wing 36 , which is characterized in that it is connected only on one side with the respective guide blade 14 , while it is otherwise arranged detached to the respective guide blade 14 . These wings 36 may thereby be integrated into the outer contour 27 as in FIG. 16 , such that their passage openings 26 are open on the side. Likewise, a distance to the outer contour 27 may be maintained in another embodiment. Two different geometries for the wings 36 are shown in FIG. 16 . FIG. 17 shows other variants A, B, C and D for the geometric shape of such wings 36 . Thus, FIG. 17A shows a wing 36 with a linear profile. FIG. 17B shows a wing 36 with a concave bent profile in the tilting direction. FIG. 17C shows a wing 36 with a convex bent profile in the tilting direction. FIG. 17D shows, on the other hand, a wing 36 with an aerodynamically shaped profile, especially a drop profile. [0080] FIG. 18 shows, in an exemplary manner, an embodiment, in which the formation of the perforation 25 by means of a plurality of various passage openings 26 with tilting devices 35 (left half in FIG. 18 ) and without tilting devices 35 (right half in FIG. 18 ), which differ from each other, moreover, by different geometries and cross sections. [0081] FIGS. 19 and 20 show another embodiment for a special perforation 25 , in which the guide blade 14 is equipped with a step 38 , which is formed by means of two bending edges 39 . In the area of the perforation 25 are provided two other bending edges 40 , which are arranged offset to the above-mentioned bending edges 39 in a blade longitudinal direction 42 , which runs parallel to the blade length 28 and in which the guide blade 14 is bent in the opposite direction. Accordingly, the tilting device also forms a step 41 , which is arranged offset in the blade longitudinal direction 42 to the step 38 of the guide blade 14 . As a result of this, two open cross sections, spaced apart from one another, which make possible a lateral inflow and lateral outflow of the exhaust gas, are formed in a blade transverse direction 43 , which extends parallel to the blade width 31 . [0082] Even though in the preferred embodiment shown here the mixer is designed as a shaped sheet metal part, it may also be designed as a cast part or a sintered part in another embodiment. The respective perforation 25 is then advantageously worked in later. [0083] While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

A static mixer ( 12 ) for an exhaust system ( 7 ) for mixing a reducing agents with an exhaust gas flow ( 8 ). The static mixer ( 12 ) has a plurality of guide blades ( 14 ) for deflecting the exhaust gas flow ( 8 ). A reduced flow resistance is obtained when at least one of the guide blades ( 14 ) has a perforation ( 25 ) through which the exhaust gas flow ( 8 ) can flow.

FIELD OF INVENTION [0001] This invention relates to putters that can be used for practice and play, with either a right or left-handed stroke. Specifically, this invention is a balanced putter that can be used for practice and play that conforms to the Rules of Golf. BACKGROUND [0002] Golf is governed by The Rules of Golf as approved by the United States Golf Association and the Royal and Ancient Golf Club of St. Andrews, Scotland, referred to herein as the USGA Rules. The most current rules are available from www.USGA.org. A typical game of golf is played on a course having 18 holes and a golfer may carry up to 14 clubs with him during play. An average golfer uses over 80 strokes to complete the game, and typically half of those stokes are putts. Therefore, the putter is by far the most important of the regulation 14 golf clubs in a golfer's bag, and improved putting will improve a player's score more than improvement in any other stroke. [0003] Consequently, thousands of devices and methods have been devised to help a golfer improve his putting, ranging from the practical to the absurd. Most of these devices do not conform to the design of clubs specified by the USGA Rules, however, and therefore are used during practice only. The golfer must switch putters to play a round of golf, thus changing the primary tool with which he perfected his stroke. As a result, the putt stokes during play are seldom as good as during practice. It would be advantageous, then, to provide a dual-purpose putter that conforms to the Rules of Golf so that the golfer can use the same putter in practice as in play. [0004] Under the USGA Rules, the putter shall have a shaft and a head, fixed to form one unit. When the golf club is in its normal position to address the ball, the shaft shall be aligned so that the projection of the straight part of the shaft onto the vertical plane through the toe and heel shall diverge from the vertical by at least 10 degrees. Further, the projection of the straight part of the shaft onto the vertical plane along the intended line of play shall not diverge from the vertical by more than 20 degrees. The USGA Rules further require that the clubhead meet specific criteria. For example, the distance from the heel to the toe of a putter shall be greater than the distance from the play face to the back. These rules limit the orientation of the shaft to the clubhead, and therefore the balance of the putter, a major factor in aligning the ball and in putting consistently. [0005] The penalty for playing a game of golf with a putter that does not conform to the USGA Rules is disqualification from the game. However, with the many rules pertaining to the design of putters, it is difficult to design a club that provides quality training features for practicing and yet can be used for play. It is desirable to provide a putter that can be used for practice and play that conforms to USGA Rules. [0006] Therefore, it is an object of this invention to provide a putter that enables the golfer to determine which strokes are the best during practice so that he may practice those strokes repeatedly and learn to stroke the ball consistently in play. It is another object of this invention to provide a putter that can be used for both practice and play, and that conforms to the USGA Rules. It is another object of this invention to provide a putter that is substantially balanced around the shaft of the club. It is an object of this invention to provide a putter in which the shaft always diverges at least 10 degrees from the sole of the clubhead, regardless which orientation the golfer holds the putter when addressing the ball. It is another object to provide a putter in which the center of gravity of the club is located along the centerline of the shaft. It is a further object to provide a putter in which the center of gravity of the clubhead strikes along the plane of the center of gravity of the ball. SUMMARY OF THE INVENTION [0007] The present invention is an improved putter that combines several features to provide a balanced putter, which assists a player in perfecting a putt stroke during practice and repeating it with the same club during play. The clubhead is substantially symmetric around the shaft and has tapered top and bottom surfaces such that the angle of the shaft relative to the sole of the putter is no more than 80 degrees. The shaft is attached at the center of the clubhead, and the clubhead and shaft are arranged so that the center of gravity of the clubhead strikes the center of the golf ball. The clubhead has a playing surface on one face that is parabolic and can be flat in the extreme. The clubhead has a practice surface on the other face that is curved, preferably elliptical, to assist the golfer in learning the proper stroke. The putter conforms to the Rules of Golf so that the player does not have to change clubs between practice and play. The club may be used for either a right- or left-handed stroke. BRIEF DESCRIPTION OF THE DRAWINGS [0008] [0008]FIG. 1( a ) is a perspective view of the practice face of the clubhead. [0009] [0009]FIG. 1( b ) is a perspective view of the play face of the clubhead. [0010] [0010]FIG. 2( a ) is a top view of the clubhead. [0011] [0011]FIG. 2( b ) is a bottom view of the clubhead. [0012] [0012]FIG. 2( c ) is a cross-section view of the clubhead 11 along line c-c of FIG. 2( a ). [0013] [0013]FIG. 2( d ) is an end view of the clubhead; each end is symmetric to the other. [0014] [0014]FIG. 3 is an exploded, perspective view of the clubhead with a curved practice face and a flat play face. [0015] [0015]FIG. 4 is a cross-section of the clubhead of an alternate embodiment of the device along line c-c of FIG. 2( a ) in which the inserts are attached to the core with mated threads. [0016] [0016]FIG. 5( a ) illustrates the angle of the shaft to the sole of the putter when the putter is standing upright. [0017] [0017]FIG. 5( b ) illustrates the angle of the shaft to the sole of the putter for a right-handed stroke. [0018] [0018]FIG. 5( c ) illustrates the angle of the shaft to the sole of the putter for a left-handed stroke. [0019] [0019]FIG. 6 is a perspective schematic view of the clubhead, indicating the sides and faces of the preferred embodiment. [0020] [0020]FIG. 7 illustrates the center of the clubhead aligned with the center of the golf ball at the instant the clubhead strikes the golf ball during a putt stroke. [0021] [0021]FIG. 8( a ) is a plan view of the practice face of the preferred embodiment, having a convex practice insert. [0022] [0022]FIG. 8( b ) is a plan view of the play face of the preferred embodiment, having a flat play insert. [0023] [0023]FIG. 9( a ) is a plan view of the practice face of an alternate embodiment, having a convex practice insert. [0024] [0024]FIG. 9( b ) is a plan view of the play face of an alternate embodiment having a parabolic, concave play insert. [0025] [0025]FIG. 9( c ) is a side view of the alternate embodiment, showing a convex practice face and a concave play face. [0026] [0026]FIG. 10( a ) illustrates a golfer practicing a right-handed putt stroke with the practice face. [0027] [0027]FIG. 10( b ) illustrates a golfer playing a right-handed putt stroke with the play face. DETAILED DESCRIPTION OF THE INVENTION [0028] FIGS. 1 - 3 , 5 , 7 and 8 illustrate the preferred embodiment of the present invention. A clubhead 11 of an improved putter 10 is attached to a shaft 12 with a hosel 13 . (For the sake of clarity, the hosel 13 is shown only in FIGS. 1, 7 and 10 .) The present device may be used with shafts of any length. The clubhead 11 has two faces, a practice face 14 and a play face 15 . Only the play face is used as a striking surface during play, thereby conforming with a USGA Rule that a clubhead have only one striking face. The practice face 14 has a substantially circular insert, referred to as a practice insert 16 . The practice insert 16 is convex relative to the practice face 14 , as best illustrated in FIGS. 2 a - d , and the practice face shape ranges from elliptical to spherical. The curved shape limits the number of points at which the practice face can strike a golf ball in order for the golf ball to move in a straight line perpendicular to the practice face, referred to as the line of putt. Hitting the center of the golf ball with the center of the practice face will cause the golf ball to move on the perpendicular line. However, if the golfer hits the golf ball with any part of the practice face other than the center of the practice insert, the golf ball will veer off the perpendicular line. The farther away from the center of the practice insert, the worse the veer angle will be. [0029] Preferably the practice insert 16 is an ellipse. With an elliptically curved practice insert, the veer is relatively small at short radii from its center, thereby being somewhat forgiving to a less-than-perfect stroke. This approximates the amount of forgiveness of putts in play, because slight deviations for a perfect line of putt will not prevent the golf ball from falling in the hole. However, as the veer angle grows increasingly larger farther away from the center of the practice face, the “penalty” for a bad stroke increases as the stokes become increasingly off-center. A spherical practice insert may also be used; it provides a less forgiving center, but a more forgiving perimeter, as the veer angle changes relatively less than at the perimeter of an elliptical practice insert. The “penalty” for a bad stroke is constant regardless of how off-center the stroke is. It is likely that a better golfer will use the spherical practice insert to fine tune his putt stroke. [0030] In addition to the curvature of the practice insert, the present invention includes alignment apertures for assisting the golfer in visualizing a straight line to the ball or other desired point. Each alignment aperture is made in the clubhead 11 to receive a lightweight post 30 that extends substantially perpendicularly from the practice face 14 . A conventional drinking straw is suitable for the post, as is it extremely lightweight and most convenient to obtain at a golf course. Preferably, therefore, the diameter of each aperture is made to enable a drinking straw to be inserted and held in place snugly simply by friction. A post can be inserted in any one or more of the alignment apertures, in whichever placement the golfer finds it assists his alignment the best. In the preferred embodiment, the practice face 14 has two alignment apertures, 18 and 20 , however more are acceptable, as indicated by aperture 21 and the aperture into which post 30 is inserted. [0031] The play face 15 also has a substantially circular insert, referred to as a play insert 17 . The play insert 17 is inwardly parabolic relative to the play face 15 , ranging from flat to concave. A flat striking face is required under USGA Rules, so a flat play insert should be used when playing a round of golf. [0032] A parabolic-shaped play insert is self-correcting to some degree, because the curve of the insert will urge the golf ball to the center of the parabola before redirecting the ball away from the play face. A parabola is the set of all points in a plane equidistant from a fixed point (called the focus) and a fixed line (called the directrix). The formula for a parabola is generally: y = x 2 4     p [0033] Thus, when p is large, the curvature of the play insert is great and the ball is strongly urged to the center of the parabola. As the parabola flattens out, that is, as p becomes small, the play insert provides less assistance in getting the ball to travel on the putt line perpendicular to the play face. When the parabola is flat, that is, when y is constant, the striking face is flat, and the putter provides no self-correcting assistance to the golfer. Preferably, the play insert 17 is flat so that the putter conforms to USGA Rules. [0034] [0034]FIG. 3 illustrates a preferred embodiment of the clubhead having a core 91 , curved practice insert 92 and flat play insert 93 . The top and the bottom of the clubhead are substantially v-shaped with flattened apexes, the tapered sides serving to position the shaft at an appropriate angle to the ground during practice and play, as described in more detail below. The clubhead is operable with sharp edges where the various faces meet, but preferably the edges are rounded. Preferably the clubhead 11 is manufactured as a core having apertures into which the shaft, practice insert and play insert are inserted to form an integral unit. The inserts must be firmly fixed so that there is little likelihood of them working loose during a round of golf. The inserts may be integral with the core 91 of the clubhead 11 , or may be separate pieces that are attached to the core or face of the clubhead, with adhesive or friction fit. FIG. 2 c shows a cross-section of the clubhead with a practice insert 92 and play insert 93 attached with a friction fit. Preferably the practice inserts and play inserts are changeable to accommodate the needs of the golfer and preferably the insets are threaded to mate with a threaded aperture in the core 91 . FIG. 4 shows a cross-section of the core 91 with a practice insert 94 and play insert 95 attached by mated threads. Preferably the inserts are flush with their respective faces. [0035] The core is made of any durable material, and preferably metal such as aluminum, brass or steel. The practice insert is also made of a durable material, but preferably a hard composite material such as a polymer that provides for a satisfying “thunk,” such as Surlyn. Surlyn is the brand name of a thermoplastic resin sold by Dupont, which was the first and most durable cover material that revolutionized the construction of the golf ball when it was introduced in the 1980s. The play insert is made of durable materials, metal or composite, and preferably the same material as the practice insert so that the feel of the practice stroke is the same as the stroke during play. [0036] For aligning the ball and for putting consistently, it is advantageous to have a putter that is balanced in as many dimensions as possible. One USGA Rule requires that the projection of the straight part of the shaft onto the vertical plane through the toe and heel shall diverge from the vertical by at least 10 degrees. In other words, the angle between the shaft and the sole of the club must be less than 80 degrees. To achieve both a balanced clubhead and this angle, the bottom of the clubhead is tapered in a V, upward from the midpoint of the bottom to the toe and heel. When putting, one side of the bottom of the club will be resting on or parallel to the playing surface. This portion of the bottom becomes the sole of the club. Due to the taper and the shaft's orientation to the clubhead, the shaft is then always tilted at least 10 degrees from vertical. FIG. 5 illustrates the resultant effect, where a is the angle between the vertical and the shaft. In FIG. 5( a ), the putter is shown in its upright position with the shaft 12 perpendicular to the playing surface 60 . FIG. 5( b ) illustrates the putter in the position as a right-handed golfer addresses the ball. Note that a is at least 10 degrees, making the shaft 12 at least 10 degrees off vertical; in other words, the angle between the shaft and the sole 31 of the club is less than 80 degrees. FIG. 5( c ) illustrates the putter in the position as a left-handed golfer addresses the ball. Note again that the shaft 12 is at least 10 degrees off vertical, so that the angle between the shaft 12 and the sole 32 is less than 80 degrees. The same angle effect holds true if a golfer first addresses the ball with the practice face and then spins the club 180 degrees in his grip to address the ball with the play face, regardless of whether the golfer uses a right- or left-handed stroke. Since the clubhead is tapered by at least 10 degrees, the shaft will always diverge at least 10 degrees from the plane through the toe and heel, regardless of which orientation the golfer uses to address the ball. To maintain symmetry and weight balance in the clubhead, the top should be similarly tapered. That is, the top of the clubhead is tapered in a V, downward from the midpoint of the top to the toe and heel. [0037] To balance the clubhead 11 , the shaft (not shown) is attached to the center of the top of the clubhead 11 , on a line Z-Z perpendicular to the horizontal centerline X-X of the play face. The clubhead 11 is substantially symmetric around the shaft 13 . In addition, the shaft extends substantially to the bottom of the clubhead. This arrangement locates the center of gravity of the clubhead along the centerline of the shaft, which makes the club feel balanced during any stroke. This further enables center of gravity of the clubhead to strike the ball along the plane of the center of gravity of the ball, eliminating the need to compensate for spin due to angular momentum of the clubhead. [0038] The clubhead 11 , therefore, is a polyhedron. Preferably the perimeter of the practice face 16 and play face 17 are octagons as shown in FIG. 6. The perimeter of the practice face has sides a, b, d, c, e, f, g and h. The perimeter of the play face has sides i, j, k, l, m, n, o and p. The practice face and play face are substantially parallel to each other, and connected to each other with a top and a bottom. The top of the polyhedron has three faces, P, Q and R that are attached to sides of the practice face a, b, c and the play face i, j, and k, respectively. The bottom has three faces, S, T and U that are attached to sides of the practice face e, f, g and play face m, n and o, respectively. The ends of the clubhead 11 are parallel to each other and perpendicular to face Q and face T of the bottom. The taper of the clubhead is the effect of the relationship of the sides to the top and bottom. In FIG. 6, the taper is therefore indicated by angle β. The angles between sides a and b, b and c, d and e, e and f, are equal and no more than 170 degrees, and the angles between sides i and j, j and k, m and n, n and o, are equal and no more than 170 degrees. [0039] To best control and eliminate spin on the golf ball, it is desirable to be able to strike the ball along the horizontal plane bisecting the center of the ball. FIG. 7 illustrates the centerline l-l of the play face 15 aligned with the center of a golf ball 79 upon impact with the golf ball. Consistent with good clubhead balance, preferably the practice and play faces are centered along the horizontal centerline of the clubhead 11 . For good visual alignment, the practice and play faces are preferably about the same size as a golf ball. Preferably, therefore, the practice and play faces have nearly the same diameter as the diameter of the golf ball and are centered on the clubhead so that the center of the practice and play faces meet the centerline of the ball when it is struck. The actual dimensions of the clubhead can be customized to take into account various factors including the player's stroke, the lay of the ball on the putting surface, and the length of the nap of the grass. Many combinations of the shapes of the clubhead, play and practice faces are possible while still achieving the objective of this invention, as illustrated in FIGS. 8 and 9. FIG. 8 illustrates the preferred embodiment, wherein the practice face 50 (FIG. 8( a )) and play face 51 (FIG. 8( b )) are octagons and the taper angle α is about 10 degrees. The practice insert 52 is outwardly convex in an elliptical curve. The play insert 53 is flat. FIG. 9 illustrates an alternate embodiment, wherein the practice face 70 (FIG. 9( a )) and play face 71 (FIG. 9( b )) are octagons, but the taper angle α has been increased to about 20 degrees. The practice insert 72 is outwardly convex in a spherical curve and the play insert 73 is convex in a parabolic curve. FIG. 9( c ) is a side view illustrating a convex practice face and a concave play face. [0040] [0040]FIG. 10( a ) illustrates a golfer 80 practicing a right-handed putt stroke into hole 83 . The golfer uses the practice face 81 to hit the ball and improve his aim. By rotating the putter 180 degrees in his hands, the golfer can use the same putter and the same stance to putt in play. FIG. 10( b ) illustrates the same golfer putting in play, using the play face 82 as the striking face. [0041] While there has been illustrated and described what is at present considered to be the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made and equivalents may be substituted for elements thereof without departing from the true scope of the invention. Therefore, it is intended that this invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.

Several features are combined to provide a balanced putter, which assists a player in perfecting a putt stroke during practice and repeating it with the same club during play. The clubhead is substantially symmetric around the shaft and has tapered top and bottom surfaces such that the angle of the shaft relative to the sole of the putter is no more than 80 degrees. The shaft is attached at the center of the clubhead, and the clubhead and shaft are arranged so that the center of gravity of the clubhead strikes the center of the golf ball. The clubhead has a playing surface on one face that is parabolic and can be flat in the extreme. The clubhead has a practice surface on the other face that is curved, preferably elliptical, to assist the golfer in learning the proper stroke. The putter conforms to the Rules of Golf so that the player does not have to change clubs between practice and play. The club may be used for a right- or left-handed stroke.

BACKGROUND Drawbacks to conventional transparent armor include the need to use thicker panels to achieve desired levels of protection, thus incurring a weight penalty, and environmental erosion and scratching of the surface, which reduces transparency. A need exists to mitigate these problems. BRIEF SUMMARY In a first embodiment, an armor system includes a hard, transparent armor substrate, and a transparent coating of atactic polypropylene bonded to the armor substrate. In another embodiment, a vehicle incorporates the armor system of the first embodiment, with the transparent coating configured to face an exterior surface of the vehicle, the armor system configured as a window, windscreen, or viewing port of said vehicle. A further embodiment involves treating the armor system of the first embodiment by heating and smoothing the transparent coating, thereby improving optical clarity thereof. BRIEF DESCRIPTION OF THE DRAWING FIG. 1 shows the increase in velocity required to penetrate armor (V-50) due to the presence of a 19 mm polyurea coating. DETAILED DESCRIPTION Definitions Before describing the present invention in detail, it is to be understood that the terminology used in the specification is for the purpose of describing particular embodiments, and is not necessarily intended to be limiting. Although many methods, structures and materials similar, modified, or equivalent to those described herein can be used in the practice of the present invention without undue experimentation, the preferred methods, structures and materials are described herein. In describing and claiming the present invention, the following terminology will be used in accordance with the definitions set out below. As used in this specification and the appended claims, the singular forms “a”, “an,” and “the” do not preclude plural referents, unless the content clearly dictates otherwise. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. As used herein, the term “about” when used in conjunction with a stated numerical value or range denotes somewhat more or somewhat less than the stated value or range, to within a range of ±10% of that stated. As used herein, the term “armor substrate” refers to new and conventional forms of transparent armor including, without limitation, laminates of soda-lime or borosilicate glass with polycarbonate as well as transparent ceramic armor including aluminum oxynitride (“Alon”), spinel (including nanocrystalline spinel), and the like, and combinations thereof. Description Elastomeric coatings were found to substantially increase the ballistic limit of underlying steel armor substrates when applied to the outside surface (that is, the “strike-face”) with a composite array of elastomer-steel panels enjoying increases armor penetration resistance, as reported in Roland et al., “Elastomer-steel laminate armor” Composite Structures 92 (2010) 1059-1064, incorporated herein by reference. Various coatings including polyurea and butyl rubber have shown to function well in this application, and the coating itself may include a combination of materials. FIG. 1 shows the increase in average velocity required to penetrate armor (V-50) due to the presence of a 19 mm polyurea coating. The coating contribution to penetration resistance systematically increases with increasing substrate hardness. On steel substrates, mass efficiencies exceeding a factor of two have been achieved. With regard to conventional transparent armor, thicker panels are required to achieve higher ballistic performance, with a concomitant weight penalty which is especially undesirably in the case of vehicles, adversely impacting performance, fuel economy, and payload, while the bulkier panels impinge on interior space. Furthermore, conventional transparent armor can be prone to environmental abrasion or scratching, reducing transparency and requiring costly and time-consuming repair. This armor system may be applied to vehicles including manned or unmanned vehicles suitable for travel on the ground, or in the air, on the surface of water or underwater, and combinations thereof. It may be used in windows, windscreens, viewing ports, and the like. As described herein, a transparent armor system includes a polymer coating applied to a transparent armor substrate. The density by area of this transparent armor system can be less than that of conventional armor systems while providing equal or greater protection. The protective function of the coating is believed to arise from an impact-induced phase transition with consequent large energy absorption, so that the substrate should be stiff enough to allow rapid compression of the coating. Atactic polypropylene with a glass transition temperature of about −20° C. functions as a suitable coating due to this phenomenon, while providing the desired transparency. Armor Substrate The armor substrate is preferably transparent and with sufficient rigidity and hardness to support the coating while also itself resisting penetration. Most preferably, the armor substrate has a hardness of at least 150, 200, 300, 400, 500 , or more, as measured using the Brinell method with a tungsten ball of 10 mm diameter and 3,000 kg force. The armor substrate may be one or more new or conventional forms of transparent armor including, without limitation, laminates of soda-lime or borosilicate glass with polycarbonate and transparent ceramic armor including aluminum oxynitride (“Alon”), spinel (including nanocrystalline spinel), and the like, and combinations thereof. Nanocrystalline ceramic material that might be suitable for use as an armor substrate is described in commonly-owned U.S. Provisional Patent Application No. 61/907,440 filed on Nov. 22, 2013, incorporated herein by reference. Traditional bullet-resistant glass is available with coatings under the trade names MARGARD and MAKROLON intended to improve scratch resistance. The present armor system may be used with any such forms of coated transparent substrates, termed secondary coatings to distinguish them from the atactic polypropylene coating of the invention. It is believed that hard coatings may increase the effective hardness of the glass, thus improving performance of the system as seen in FIG. 1 . The polypropylene coating senses the hardness of the substrate of length-scales commensurate with the wavelength of the longitudinal pressure wave—this may guide the design of the thickness of a secondary coating. Coating The polymeric coating is preferably atactic polypropylene. It was found that isotactic polypropylene would crystallize and fail to provide the desired ballistic performance. A suitable molecular weight may be from about 40 to about 80 kilograms/mol for an atactic polypropylene polymer. In preparing the polymer, it should be cooled quickly to avoid formation of crystals large enough to scatter visible light. The coating thickness may range, for example, from about 0.25 cm to about 2.0 cm. The coating may be bonded to the armor substrate using various techniques. It may be in direct contact with the armor substrate or bonded thereto via an intermediate adhesive. It may be cast into place on the armor substrate. Mechanical bonding may be used, for example using a frame, clamps, bolts, or other fasteners. A combination of bonding techniques may be used. An advantage of this transparent polymeric coating is its reversible solidification (as opposed to solidification via a practically irreversible chemical change in other polymers). Thus, abrasions and scratches may be removed by heating, optionally while contacting the surface of the polymer with a smooth surface. It was found that a temperature of about 100° C. was sufficient to repair atactic polypropylene. Such repairs could easily be made in the field. Concluding Remarks All documents mentioned herein are hereby incorporated by reference for the purpose of disclosing and describing the particular materials and methodologies for which the document was cited. Although the present invention has been described in connection with preferred embodiments thereof, it will be appreciated by those skilled in the art that additions, deletions, modifications, and substitutions not specifically described may be made without departing from the spirit and scope of the invention. Terminology used herein should not be construed as being “means-plus-function” language unless the term “means” is expressly used in association therewith.

A coating of atactic polypropylene over a transparent armor substrate improves resistance to penetration while allowing convenient repair of minor abrasions and scratches.

BACKGROUND OF THE INVENTION The present invention relates to semi-conductor integrated circuits of the type comprising configurable logic circuit arrays. The invention is a development of the configurable logic circuit arrays disclosed in our British Patent Specification No. 2180382 (having a corresponding U.S. Pat. No. 4,935,734) and U.S. Pat. No. 5,001,368. In the former, the logic circuit array comprises a matrix of discrete sites or cells at each of which is a logic circuit which is adapted to perform a simple logic function. Typically the simple logic function is implemented by means of a two input NAND gate. As made each logic circuit has what may be referred to as a restricted signal translation system by which each logic circuit has selectable direct connection paths to only a few of the other logic circuits. More particularly each direct connection path which is selectable as to its conduction state, extends, for each said logic circuit, from its output to inputs of a first set of some of other said logic circuits and from its inputs to outputs of a second set of some of other said logic circuits, all of the sets (for all of the logic circuits) each being unique. Such a restricted signal translation system provides what can be conveniently referred to as local direct connection paths. An array of this type is capable of being programmed in such a manner as to configure the various NAND gates, as required, to perform various and different logic functions. One such function is known as a latching function and in the logic array as disclosed in Specification No. 2180382, a latching function may be implemented using four NAND gates. This has the disadvantage that the greater the number of latching functions that may be required from any logic array, the fewer NAND gates remain for other required functions. This has the effect of reducing the overall effectiveness of the array. The invention of U.S. Pat. No. 5,001,368 overcomes this disadvantage by providing an additional logic circuit for inclusion in each of the logic circuits at each discrete site to enable each site to have a greater programmable facility and thereby increase the overall utilisation of the array. As with GB 2180382 the site/cell of each logic circuit has the aforesaid restricted signal translation system. Each additional logic circuit is arranged within the logic circuit of the site or cell to be selectively controlled by control means to cause each logic circuit and additional logic circuit comprising each cell to operate as either a first or a second different simple logic function. More particularly, each cell is constructed to operate as a NAND gate or as a latch circuit function. Providing such local direct connection paths between physically neighbouring logic circuit sites facilitates the establishment of a desired particular circuit function in a localised configuration of logic circuits, ie. in part only of the chip area occupied by an appropriate number of discrete sites of the logic circuits and by the direct connection paths. Interconnections between such localised configurations for overall circuit/system requirements can be either simply by said direct connection paths or by a further signal translation system by way of a direct connection bus directly connected to the logic circuits and extending throughout the array--for example as a series of rows and columns. Such connections might conveniently be referred to as global connections. The so-called local direct connections and global connections constitute routing resources which are used to connect to discretely programmed logic functions. These resources can be combined by routing through a cell in order to complete the connection between functions. Once a logic circuit has been used in this matter to complete the routing that logic circuit can no longer be used for function. This reduces the overall effectiveness of the array. An object of one aspect of this invention is to overcome this disadvantage by providing additional connection resources in an arrangement not previously contemplated. A feature of the afore-described configurable logic arrays is that each discrete site or cell is identical thus in the case of GB 2180382 each discrete site comprises a NAND gate whilst in the case of U.S. Pat. No. 5,001,368 each discrete cell comprises a NAND gate and an additional logic circuit which enables the cell to function exclusive as a NAND gate or exclusively as a latch circuit function Implementing other circuit functions (be they logic functions or otherwise) requires the various cells to be configured as required to perform various and different circuit functions Other functions frequently required are XOR and D-flip-flop. Again this has the disadvantage that the greater number of these functions that may be required from any logic array the fewer gates remain for other required functions which has the effect of reducing the overall effectiveness of the array SUMMARY OF THE INVENTION An object of one aspect of this invention is to overcome this disadvantage by providing a series of different types of cells (eg. providing different functions) and arranged in a particular manner in the array to thereby increase the overall utilisation of the array. According to said one aspect of the invention a semi-conductor integrated circuit comprises an area thereof formed with a plurality of logic circuits at discrete sites or cells respectively defining a matrix array of cells, and wherein the matrix array of cells is sub-divided at least into zones each comprising a matrix array of said cells and further comprising a porting arrangement for each zone, the integrated circuit as made having an hierarchical routing resource structure comprising: (i) global connection paths having selectable connections with the porting arrangement of each zone, (ii) medium connection paths extending between the porting arrangement and at least some of the cells in a zone, and (iii) local direct connection paths comprising for each cell a restricted signal translation system between inputs and outputs of the cells each selectable as to its conduction state, those paths extending for each said logic circuit from its output to inputs of a first set of some of other said logic circuits and from its inputs to outputs of a second set of some of other said logic circuits, each first set of logic circuits being different from any other first set of logic circuits, and each second set of logic circuits being different from any other second set of logic circuit. In essence the present invention provides a semiconductor integrated circuit comprising an area thereof formed with a plurality of logic circuits at discrete sites with three levels of interconnect, namely global, medium and local, and are brought about by the existence of the porting arrangement that separates the array into zones. The global level interconnect can span the whole array but is separated from the medium and local level interconnects by the porting arrangement, the medium interconnect extend at a zone but can connect directly with port cells and core cells, whilst the local interconnect provides connections between only a few cells. The zones are preferably arranged in a matrix array of zones, the plurality of zones defining a quadrant and the integrated circuit may have a plurality of quadrants also conveniently arranged in a matrix array. In a preferred construction there are 10×10 cells to a zone and 5×5 zones to a quadrant and 2×2 quadrants. The global connection paths conveniently extend horizontally and vertically across a plurality of zones. Indeed it is preferable to have the global connection paths comprise lines which extend continuously across more than one zone and which are selectably connectable with at least some of the zones. Preferably there are a plurality of global connection paths for each row and column of cells in a zone. More preferably still there are four global connection paths for each row and column of cells. As concerns the medium connection paths, it is preferred to have a plurality of these for each row and column of cells of a zone, and preferably four for each row and column. Each medium connection path is selectably connectable with an output and/or input of one or more cells. Preferably the semi-conductor integrated circuit comprises further global routing resources comprising horizontal and vertical buses extending across a zone horizontally and vertically respectively, and which are connectable with the port cells and with one another. It is preferred that they are not connectable to the cells. Conveniently there is one such additional global connection bus for each row and column of cells, and preferably there is a connection between the horizontal and vertical buses for each cell. Conveniently such additional global connection paths are referred to as x buses. It is convenient to have horizontal and vertical port cells. The porting arrangement permits resources to be routed from the global lines through to the medium lines and thereby into the cells without necessarily having to use cells for routing thereby leaving more cells available for function. The use of port cells is also advantageous in that it allows the general interconnect structure (global and medium buses) to interconnect with special interconnect structure, for example clocks and tristates. Accordingly, the circuit advantageously further comprises clock distribution channels, preferably comprising-a vertical clock bus (with say 8 lines) extending between clock pads to top and bottom of the array, a horizontal clock distribution spine (with say 8 lines), extending between clock pads to opposite sides of the array and intersecting with the vertical clock bus. Preferably there is a vertical clock distribution spine for each zone (conveniently tapped off from the horizontal clock spine) by which clock and reset signals are distributed to the vertical port cell of that zone. Preferably alternate core cells have clock and reset signal lines. Buffers are used in the clock signal distribution lines as appropriate. Further advantageous of signal paths arise from dedicated connection lines with the horizontal port cells, specifically wired -OR buses (say 5) running across each zone and connecting directly with the wired -OR core cells. Preferably connection of the wired -OR buses may be made to a certain (restricted) number of global buses, eg. by way of the horizontal port cells. A further advantageous feature is to have wired -OR connections between horizontal x buses and say three horizontal global buses. Pull ups are advantageously provided for the WO buses, eg. in the horizontal port cells, and pull ups for the global buses are advantageously situated in the vertical inter-quadrant region . The preferred connection provisions afforded by the porting arrangement will be described further hereinafter, along with other features of the integrated circuit. According to said another aspect the invention provides a configurable semi-conductor integrated circuit comprising a matrix array of core cells each of the cells having a first simple function in common and at least one subsidiary function, there being at least two different subsidiary functions, the core cells being grouped in tiles comprising a matrix array of the core cells and wherein each tile has at least one of each different subsidiary functions. The tiles comprise a matrix array of the core cells smaller than the whole array The arrangements of subsidiary functions within the cells of the tile are substantially different The resultant tile of core cells is arranged so as to uniformly cover the array Said another aspect the invention has a particular application with the circuit configuration described in the aforesaid British Patent No. 2180302. Accordingly in that application said another aspect may be defined by a configurable semi-conductor integrated circuit which comprises an area thereof formed with a plurality of logic circuits at discrete sites or cells respectively, each said logic circuit having in common a restricted simple logic function capability and itself only being capable of implementing a simple logic function, and the cell having a restricted signal translation system between inputs and outputs of the logic circuits affording (local) direct connection paths each selectable as to its conduction state, those paths extending, for each said logic circuit, from its output to inputs of first set of some of other said logic circuits and from its inputs to outputs of a second set of some of other said logic circuits, each first set of logic circuits being different from any other first set of logic circuits, and each second set of logic circuits being different from any other second set of logic circuits, the integrated circuit further comprises at each discrete site or cell additional optionally selectable circuit configurations selectively controlled by control means to enable each cell to operate in a selected one of two or more ways, and wherein there are a plurality of different optional circuit configurations and wherein the cells are arranged in groups, hereinafter referred to as tiles, with each tile having at least one of each of the different circuit configurations. The selected one of two or more ways comprises either the simple logic function common to each cell or a selected subsidiary function afforded by the optionally selectable circuit configurations. The arrangements of the subsidiary functions within the cells of the tile are substantially different, and the resultant tile of cells is arranged so as to uniformly cover the array. According to this aspect, there is provided a uniform array with externally identical cells allowing a uniform interconnect structure to be used regardless of the function of the cell. The interconnect is identical for all cells within a tile. In use the autolayout tools will know which cell supports which function but if the common function only is used then the array can be treated completely uniformly, ie. if the subsidiary functions are not used then the array appears as a uniform array of simple primary functions. There is a hierarchy of functions within the array. It is possible to implement most logic functions using the primary function only, ie. the simple cells, eg. the AND gates with programmable inversions on the inputs but this is not very efficient In order to improve the efficiency of the uniform base array it is overlaid with the subsidiary functions. The subsidiary functions represent optimised implementations of functions that can be created using the primary functions. By using this hierarchy the autolayout tools have a flexible uniform target for placement purposes for the more common functions with a slightly coarser target for the less commonly used secondary functions. The secondary functions could not be used on their own to complete a design. An hierarchy of function is preferred as opposed to an arbitrary distribution of different logic functions. The additional or subsidiary functions are distributed throughout the array. A group of commonly used functions are selected on the basis of their frequency of occurrences within gate array designs. The selected group of functions are -distributed throughout the array as the tile, which is repeated in a regular pattern over the array. The autolayout placement target for the primary function is a cell whilst the placement target for a secondary function is a tile. Although the tile is a coarser target it still represents a uniform resource throughout the array. In one embodiment the common simple logic function is a NAND gate. Preferably the optionally selectable circuit configurations afford optional functions of:-wired -OR output buffer--which is to be viewed as a function for the purposes of this specification; XOR; D-type flip flop (with reset and enable) and latch function (with reset and enable). Thus four different subsidiary functions are available, and the above recited function are the preferred subsidiary functions. As specified above each tile has at least one each of the available subsidiary functions. Some cells may have additional circuit configurations to facilitate by virtue of the tile arrangement building up higher level functions, for example a 2-to-1 multiplexer, or fast carry logic. These subsidiary functions are chosen because they are functions which are commonly required and which would otherwise be arrived at by configuring several of the basic function cells. We have identified that the number of different subsidiary functions which need to be employed in configuring of an integrated circuit to perform as desired results in some subsidiary function being required more frequently than others. Thus we prefer to have the number of different subsidiary functions available to a tile reflect this. Thus we prefer to have two XOR functions to a tile. Furthermore, by having one cell offer optionally two functions (preferably the D-flip flop and latch) an advantages construction can be arrived at with a smaller tile configuration. Our preferred tile comprises four cells, preferably arranged as a matrix of 2×2 cells, and thus in the preferred embodiment whilst there is notionally one different subsidiary function for each cell, we prefer to have two cells offering the XOR functions, one cell offering the wired-OR function and one cell offering the option of D flip flop or latch function. Each cell has available to it its basic function, ie. a NAND gate. The preferred arrangement of 2×2 cells with the above preferred distribution of subsidiary functions is such as to naturally form efficient larger elements such as adders, counters and multiplexers. As mentioned above for the preferred application each cell has the restricted signal translation system providing direct local interconnections between only some of the cells. However, it will be appreciated that the tiling arrangement can be utilised in circuits without this specific restricted translation system Preferably the integrated circuit has additional connection resources as described above and hereinafter according to said one aspect of the invention. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described further, by way of example only, with reference to the accompanying drawings, in which: FIG. 1 is a diagrammatic representation of the hierarchical structure of a configurable logic array embodying the inventions hereof, FIG. 2a shows schematically the basic function of a tile of four cells used in the array of FIG. 1, FIG. 2b shows schematically the alternative functions for each cell of the tile of four cells of FIG. 2a, FIG. 3 illustrates diagrammatically one embodiment of local connections between cells, FIG. 4 illustrates diagrammatically one series of medium connection paths to the four cells of a tile, FIG. 5 illustrates diagrammatically a zone of cells and the associated vertical and horizontal port cells, FIG. 5a shows further details of the zone of FIG. 5, FIG. 5b illustrates a corner zone, FIG. 6 illustrates diagrammatically details of connections made via the horizontal port cells, FIG. 7 illustrates diagrammatically details of connections made via the vertical port cells, FIG. 7a illustrates diagrammatically details of connections made via the vertical port cells at the top and bottom edges of the array, FIG. 8 illustrates diagrammatically details of connections between quadrants, FIG. 9a illustrates diagrammatically the primary clock structure, FIG. 9b illustrates further details of the clock structure of FIG. 9a, and FIG. 10 illustrates diagrammatically the hierarchy of interconnect provided according to the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring firstly to FIG. 1, this illustrates an overview of the hierarchical structure of the configurable logic array embodying the inventions hereof. The array of the illustrated embodiment consists of 10,000 core cells CC, all of which can be used as a simple NAND gate. For convenience the following description describes the array as a regular array of cells, comprising rows and columns. A matrix array of 10 by 10 core cells CC with associated port cells (described further hereinafter with reference to FIGS. 6 and 7) constitutes a zone 11 (see FIG. 5a) of which there are 100 in the illustrated embodiment. A matrix array of 5 by 5 zones constitutes a quadrant 13. In the illustrated embodiment the quadrants are disposed in a 2 by 2 matrix array. Inter-quadrant switches (generally designated by reference SG see FIG. 8) are provided between the adjacent quadrants. The array is also provided with user input output cells designated by blocks 17 (FIG. 1) and the illustrated embodiment has 50 per side. Also provided are input/output multiplexers 18. The circuit also has a clock structure (including clock pads CP and clock bus CB) which is described further with reference to FIGS. 9a and 9b. Referring now to FIGS. 2a and 2b, here there is illustrated diagrammatically a group of 4 core cells hereinafter referred to as a tile T and disposed in a 2 by 2 matrix array. Each cell comprises a two-input-NAND gate N1, multiplexer means M1, 2, 3 and 4 on the input side and inverters I1, I2 between respective multiplexers M1, M3, M2, M4. Each cell also has an output multiplexer M0. In addition to the facility for each core cell to be used as a simple NAND gate as represented by circuity illustrated diagrammatically in FIG. 2a, each core cell has an extra function box (fn) that can be selected during configuration. There are a plurality of different functions available and each tile contains at least one of the available functions. The 4 cells making up a tile are designated by the numbers 1, 2, 3 and 4 respectively (see FIGS. 2a, 2b) denoting different types of core cell (ie. CC-1, CC-2, CC-3, CC-4). In the illustrated embodiment the alternative function available to the type 1 cell is a wired-OR configuration, the additional function available to the type 2 cell is that of XOR as well having circuitry to provide half of a 2-to-1 multiplexer, or fast carry logic. The CIN input is driven from the type 4 cell of the tile below. The COUT output is input to the type 4 cell above. The CIN and COUT signals form the first carry logic. The type 3 cell in the illustrated embodiment has two alternative available functions, namely a D flip flop or a latch (each with reset and enable). The type 4 cell also has as its alternative function the x-OR function and additionally has the other half of the circuitry providing a 2-to-1 multiplexer or fast carry logic. The multiplexer and fast carry alternative functions require 2 core cells, thus the circuitry of the type 2 and type 4 cells are used together. In the context of the present application the wired-OR output driver of type 1 cell is to be regarded as an alternative function although strictly speaking it is not a true alternative function in the sense of the other functions. FIG. 2b shows circuitry representative of the functions available to the 4 types of core cell. The tiles are arranged into zones as mentioned above and connections within zones are made using local interconnects described further with reference to FIG. 3, or medium range interconnect to anywhere in the zone. The latter comprise horizontal and vertical medium buses M which run the length and breadth of each zone (4 per row and column of cells). These are designated as M1, M2, M3, M4. Port cells (VPC and HPC) (FIGS. 5, 5a, 5b, 6 and 7) at the edge of each zone make connections via the medium buses to neighbouring zones or to the global bus network. Horizontal and vertical x buses (referenced x) (FIGS. 5 and 5b) also run the length and breadth of each zone (1 per row and column of cells) and in conjunction with a switch (not illustrated) in each core cell they are used for making right angled turns on these buses. Global buses G (FIG. 5a) run the length and breadth of each quadrant and in the illustrated embodiment there are 4 per row and column of core cells identified as G1, G2, G3 and G4 (FIGS. 5a, 6 and 7). Switches SG1 . . . SG4 (FIG. 8) between the quadrants allow global buses-to run the whole length of the device if required. It is envisaged that all devices will have 4 quadrants but the number of zones in each quadrant may differ from one device to another. It is however preferred to have a matrix of 10 by 10 core cells to each zone. The global resources available to the array comprise the global interconnect lines G1 . . . G4 and associated switches SG1 . . . SG4. The additional letters V and H are used throughout to denote vertical and horizontal connections, cells and switches etc. as the case may be. Global resources further comprise the above-mentioned x buses described further herein below and port cells that connect between global and zone resources. There are 10 port cells along the top of each zone (the vertical port cells VPC) and 10 along the right hand side (the horizontal port cells HPC). Connections between routing resources within zones via the medium buses M1 . . . M4 and the global resources are only possible through the port cells. Port cells also support connections between medium buses in adjacent zones and are used for clock and tristate net distribution described further hereinafter. Referring now to FIG. 7 here we illustrate diagrammatically how the zone and global buses connect to the vertical port cells VPC. Port cells are arranged in pairs, aligned with the core cell tiling. Four routes are possible through each port cell-multiplexers A and C support one route each, and multiplexer B (shown as B1 and B2) supports two separate connections. Two of the zone medium buses (M1 and M2) are used for connections to the global and x buses through multiplexers A and C. In addition, M1 and M2 from the adjacent column in the tile also connect to A and C. This arrangement allows a cross over connection between pairs of port cells. Multiplexers A and C also provide bufferred connections from M1/M2 or M1/M2 in the column from the adjacent column in the tile to or from M3/4 in the zone above. The other two zone medium buses (M3 and M4) connect to multiplexers B1 and B2. B1 and 2 allow two independent unbufferred links to M3 or M4 in the zone above. M3 and M4 can be interchanged using a programmable twist. These interzone connections can be used when a fast connection is required between zones. Alternate port cells have either a clock (CLK) or a reset (RST) multiplexer. These select the source for the dedicated clock and reset lines to the D flip flop and latch core cells, ie. the type 3 cells. The clock or reset multiplexer provides programmable inversion of clock and reset. Referring now to FIG. 7a, here will illustrate the connections at the top and bottom edges of the array. At the top edge connections to the vertical port cell (VPC) are with the input/output cells 17 by way of the input/output multiplexers 18. In the illustration there are two 7:1 multiplexers and one 2:1 multiplexer for each adjacent pair of port cells. It will be seen that the lines emerging from the two horizontal port cells correspond to those of FIG. 7 and that each port cell connects with a respective 7:1 multiplexer. In addition the two x buses from each port cell have a branch into the 2:1 multiplexer which communicates with control circuitry. At the bottom edge of the array, the lines passing over the zone boundary also connect with input/output cells 17 via multiplexers. For two adjacent cells also comprises a respective 7:1 multiplexer and a common 2:1 multiplexer. The lines comprise Global lines (G1 . . . 4), the x bus and medium interconnect lines M3, M4. The respective x buses are branched to the 2:1 multiplexer as at the top edge. Note in each case one 7:1 multiplexer feeds to an output cell 17 OUT and one is fed from an input cell 17 IN. In the illustrated embodiment, the input/output connection at the edges mirror the connections between zones. This is not to be taken as limiting, merely an example and the connection to the input/output multiplexers may be for more extensive. For example other of the medium interconnect lines may be substituted for M3, M4 or supplement them. In the illustrated embodiment the medium interconnect lines M1, M2 terminate at the lowermost cell of each zone, ie. they do not pass over the zone boundary. The connections to the input/output cells of the right and left edges of the array according to one embodiment mirror the connections to the horizontal port cells (HPC) as illustrated in FIG. 6 in a corresponding manner to the arrangement of FIG. 7b, utilising two 7:1 multiplexers for each pair of adjacent cells and a corresponding 2:1 multiplexer for the x buses. The primary clock structure will now be described. Primary clocks may originate external to the device via 8 special purpose-clock pads CP or from the array by routing on general resource to the clock pads. The clock pads CP are situated at the corner of each quadrant (see FIG. 1) and illustrated in further detail with reference to FIG. 9a which is a chip level diagram. The clock bus CB runs vertically between the top and bottom clock pads CP and connects with a horizontal clock spine HCS (having 8 lines) running between the horizontal clock pads to opposite sides of the array. A central clock buffer CCB is disposed at the intersection of the vertical clock bus CB and the horizontal clock spine or bus (HCS). A total of 8 global signals (clocks or reset clocks) may be driven; these can be either internally or externally generated. Any normal user I/O input signal may also be used as a primary clock by simply routing it internally to one of the clock pads. The horizontal clock spine is tapped off at various points to drive multiple vertical clock spines VCS which run between adjacent zones to provide one vertical channel of 8 global clock signals per column of array zones In addition there are equivalent vertical channels for the I/O zones to the left and right hand sides of the device. The I/O zones to the top and bottom of the array connect to the vertical clock distribution channels driven up and down through the array. The primary clock and reset signals are input into the vertical port cells of each zone via the zone clock and reset cells. An 8-2 multiplexer (FIG. 9b) distributes signals from the VCS into the vertical port cell VPC and as described with reference to FIG. 7 alternate core cells CC have a clock switch or a reset switch whereby clock (CLK) or reset (RST) signals can be distributed vertically through the zone (see also FIG. 9b). Secondary clocks can also be provided using conventional routing resource of the circuit. A routing comb is created by the software consisting of the horizontal spine and vertical teeth. The spine and teeth are routed on global interconnect and connected via x bus switches. The global interconnect may be extended across quadrant switches. The clocks are input into zones via the zones vertical port cells (which also provide programmable clock inversion), the clock can only be connected to flip flops on the same column as the secondary clock. Tertiary clocks may also be provided using conventional routing resource and our input into zones via the zones vertical port cells and can be routed on any level of interconnect. Referring now to FIG. 6 which illustrates detailing of the horizontal port cell HPC. These provide the same medium, global and x bus connectivity as the vertical port cell described above. Since the primary clock and reset signals are distributed only from the vertical core cells down core cell columns, the horizonal port cell contains no clock/reset logic. Instead, it provides support for tristate buses. Tristates are implemented using a dedicated horizontal bus within the zone (the WO bus) plus the horizonal global interconnect. The wired -OR output from the type 1 cell subsidiary function is connected to the horizontal port cell via the dedicated horizontal WO bus. The WO bus connects to multiplexer C in the horizontal port cells The internal multiplexers for normal interconnect are the same as those for the vertical port cells. The functional tiling within the zones means that only half the core cell rows contain core cells with wired-OR drivers. Therefore, there are only five wired-OR buses per zone. This means that there have to be two types of port cell, one with zone wired-OR bus connecting to it (type 1), and one without (type 2). The zone wired-OR bus from the type 1 horizontal port cell is fed to the type 2 cell as indicated by line F. This means that a WO bus can drive into horizontal global buses in every row. The x bus can also make a wired-OR connection onto the global buses, allowing vertical steps between wired-OR buses This connection can be inverted as required to maintain the sense of signals. With regard to the global interconnections, horizonal and vertical global buses run across each quadrant connecting to each zone via its port cells, see FIGS. 5, 5a, 6 and 7. The global buses connect to the I/O cells at the periphery of the device. There are 200 user configurable I/O cells 17 and these are arranged so that they pitch match 1 to every two core cells around the edges of the device. Global, medium and x buses (G1 . . . G4, M1 . . . M2 or M3 . . . M4, X) from one core cell row or column are used as inputs and G1 . . . G4, M1 . . . M2 or M3 . . . M4 and X from the adjacent row or column are used as outputs. An 8 bit peripheral bus runs around the whole device which is accessed by the I/O cells. Each I/O cell can read or write any of the 8 bits. Wired-OR buffers can optionally be selected when writing to the peripheral bus. Referring again to FIG. 5, the basic structure of a zone is illustrated showing the vertical port cells VPC and the horizontal port cells HPC described with reference to FIGS. 7 and 6 respectively. Also illustrated is the zone CLK/RST multiplexer. Referring to FIG. 3, regarding the local interconnect of each cell, the upper and lower input multiplexers (A and B) of each core cell can be connected to the outputs of nearby cells using the network of local interconnect. This provides the fastest connections between cells. Thus in the illustrated embodiment the multiplexer A provides inputs to the core cell C from the outputs of cells U, LL, F, FB and FF, whilst the multiplexer B provides inputs to the core cell C from the outputs of cells UU, L, F, FB and FBB. Thus in the illustrated embodiment each cell connects with its eight nearest perpendicular neighbours. Each cell C will have a set of local connection possibilities. Ie. each cell connects with only some of the other cells in a manner described in our British patent 2180382. Referring now to FIG. 4, this illustrates how medium interconnect is used for connections within a zone that are not possible with local interconnect. Medium buses are also used for interzone connections since they connect to the port cells. There are four horizontal and four vertical medium buses per row and column of core cells. All medium buses connect to the zones port cells, but only two can be used for connection to the global routing network in the illustrated embodiment and these are referred to as M1 and M2 or the external medium buses. M3 and M4 "the internal" medium buses, are used for connections through the port cells to all four adjacent zones as will be apparent from reference to FIG. 6 and 7. Each of the two input multiplexers in a core cell provides connections from two medium buses. The core cell output multiplexers can connect to four medium buses. Therefore each individual core cell can only access half the 8 medium buses that cross each cell. To compensate for this there is a tiling of bus connections, using two different sets of connections, repeated in a 2 by 2 tile similar to the core cell functional tiling Thus, for the illustrated embodiment each core cell in the tile connects to its horizontal and vertical medium buses as set out in table 1 below. TABLE 1______________________________________Corecell Mux Connections from: Connections to:______________________________________2/3 A M3(Vert),M2(Horiz) --2/3 B M1(Vert),M4(Horiz) --2/3 OP -- M2,M3(Vert),M1,M4(Horiz)1/4 A M2(Vert),M3(Horiz) --1/4 B M4(Vert),M1(Horiz) --1/4 OP -- M1,M4(Vert),M2,M3(Horiz)______________________________________ FIG. 10 illustrates diagrammatically for illustrative purposes the hierarchy of interconnect and shows three interconnect structures, namely firstly, the local interconnect structures which only have the scope of a few cells, and cannot connect to port cells, secondly the medium interconnect structures (M) which only have the scope of a single zone but can directly connect with port cells and core cell, and thirdly the global interconnect (G) which can span the whole array but cannot connect to core cells (CC). It will be apparent that these three levels of interconnect will be brought about by the existence of the porting arrangement that separates the array into zones. The global level of interconnect is separated from the medium and local levels of interconnect by the porting arrangement.

A configurable semi-conductor integrated circuit has an area thereof formed with a plurality of logic circuits at discrete sites or cells respectively defining a matrix array of cells. The matrix array of cells is subdivided at least into zones, each having a matrix array of cells, and further includes a porting arrangement for each zone; and a hierarchical routing resource structure including: (i) global connection paths having selectable connections with the porting arrangement of each zone and which extend continuously across more than one zone, (ii) medium connection paths extending from the porting arrangement and selectably connectable with at least some of the cells in a zone, and (iii) local direct connection paths having for each cell a restricted signal translation system between inputs and outputs of the cells and defining first and second sets of logic circuits.

TECHNICAL FIELD The subject invention relates generally to a prosthetic bone implant and more particularly to a trapezial resurfacing prosthesis. BACKGROUND ART Conditions such as osteoarthritis, cancer or trauma may cause degeneration of the articular surfaces between the trapezium and the first metacarpal in a hand causing the patient discomfort and sometimes severe pain during thumb circumduction. Various total replacement prosthesis have been proposed for bones in the human wrist. For example, U.S. Pat. No. 4,936,860 to Swanson, issued Jun. 26, 1990, discloses a metallic total scaphoid replacement implant. Also, U.S. Pat. Nos. 4,955,915 and 4,969,908 both to Swanson, issued Sept. 11, 1990 and Nov. 13, 1990, respectively, disclose total lunate replacement implants. Although not directed to a carpal bone implant, U.S. Pat. No. 4,936,854 to Swanson, issued Jun. 26, 1990, discloses an implant anchored in the radius and having a cupped, or dished, surface for stabilizing the proximal carpal row and preventing ulnar migration thereof. As an alternative to total carpal bone replacement, it is well known in the art to resurface the distal surface of the trapezium with a prosthetic implant. For example, the Silastic® Trapezial Implant H.P., manufactured by Dow Corning Wright Corp. 5667 Airline Road, Arlington, Tenn. 38002, is made from medical grade silicone rubber elastomer for use as an interpositional spacer between the trapezium and the first metacarpal joint of the thumb. The implant is provided with a short cylindrical stem extending from its proximal surface which fits into a cavity prepared in the trapezium. The head, or distal articular surface, of the implant is thin and dome-shaped. One of the goals of implant design is to minimize the production of wear debris particles. Wear particles can never be completely eliminated with presently available implant materials because all moving parts, e.g., implants that articulate against bone, wear to some degree. It is generally believed by some that elastomers generate wear particles at a more accelerated rate than inelastic materials. However, because the distal articular surface of the aforementioned Silastic® Trapezial Implant H.P. is domed, i.e., not anatomically representative of a natural trapezium, that implant must be manufactured from an elastomer due which has the ability to deform so as to better articulate with existing joint anatomy. SUMMARY OF THE INVENTION AND ADVANTAGES The subject invention provides an implant for attachment to the distal surface of a prepared trapezium. The trapezial implant comprises a base member having a proximal attachment surface and a distal articular surface, and anchor means extending from the proximal attachment surface for anchoring or fixing the base member to the prepared surface of the trapezium. The distal articular surface includes a convex medial portion, a convex lateral portion, and a concave central portion between the medial and lateral portions defining a distinctive and complex surface curvature for providing stable support to an adjacent first metacarpal through the entire arc of thumb circumduction. That is, the complex surface curvature provides improved articulation with the adjacent first metacarpal because its configuration closely replicates the normal human distal trapezium articular surface. In other words, the distal articular surface mimics the natural joint anatomy. The specific shape of the distal articular surface provides improved articulation between the distal articular surface of the implant and the first metacarpal thereby reducing the production of wear particles due to attrition. Further, because the distal articular surface is formed having medial and lateral convex portions and a central concave portion, the base member can be fabricated from an in-elastic, less abradable materials than the prior art elastomers. Thus, the subject invention overcomes a need inherent in the prior art domed trapezial implants fabricated from silicone elastomers. BRIEF DESCRIPTION OF THE DRAWINGS Other advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following Detailed Description when considered in connection with the accompanying Drawings wherein: FIG. 1 is a simplified dorsal view of a human skeletal hand showing the distal articular surface of the trapezium excised; FIG. 2 is a view as in FIG. 1 showing the subject trapezial implant operatively positioned on the trapezium; FIG. 3 is a perspective view of a trapezial implant according to the subject invention; FIG. 4 is a plan view of the implant as in FIG. 3; FIG. 5 is a front elevational view of the trapezial implant as in FIG. 4; FIG. 6 is a plan view of a first alternative embodiment of the trapezial implant; FIG. 7 is a end view of the trapezial implant as in FIG. 6; FIG. 8 is a perspective view of a second alternative embodiment of the trapezial implant; FIG. 9 is a plan view of the trapezial implant as in FIG. 8; and FIG. 10 is a front elevational view of the trapezial implant as in FIG. 9. DETAILED DESCRIPTION Referring to the Figures, wherein like numerals indicate like and corresponding parts throughout the several views, a human hand skeleton is generally shown at 20 in FIGS. 1 and 2. The hand 20 includes first 22, second 24, third 26, fourth 28, and fifth 30 metacarpals. The first metacarpal 22 is located medial relative to the fifth metacarpal 30. The hand 20 has a carpus comprising eight bones, including the trapezium 32. Some physical conditions, e.g., arthritis, cancer, trauma, etc., necessitate arthoplastic surgery to prosthetically improve the articular surfaces between the first metacarpal 22 and the trapezium 32. The prior art has taught both total replacement as well as resurfacing of the trapezium 32. In many instances, resurfacing is preferred and more conservative of bone than total excision of the trapezium 32. The trapezium 32 is prepared for the hemiarthroplasty as follows. The carpometacarpal joint of the thumb is exposed through a transverse or curved longitudinal incision. The superficial sensor branch of the radial nerve is identified and protected. The abductor pollices longus tendon is detached at its insertion and the extensor pollices brevis tendon is retracted. The joint capsule is opened and preserved. The marginal osteophytes at the base of the metacarpal 22 and trapezium 32 are removed with a rongeur. Distal traction of the thumb allows the joint surfaces to be well-visualized. With either an osteotome or power sagittal saw, the saddle 34 of the trapezium 32 is converted to a flat surface 36, and the medial osteophyte is removed. Excision of this medial spur permits further debridement of the capsule and reduction of the subluxed metacarpal. It is imperative that all bony obstruction to metacarpal reduction be removed. FIG. 1 illustrates the distal articular portion or saddle 34 resected from the trapezium 32, such as by conventional procedures as described above. This saddle 34 is excised to form a stable, transverse interface 36 to eliminate shear stresses. In place of the excised saddle 34, a trapezial implant, generally indicated at 38 in FIGS. 2-5, is attached to the trapezial bone 32, as shown in FIG. 2. The implant 38 includes a base member 40 preferably fabricated from an inelastic and abrasion resistant material, such as commercially pure titanium, other medical grade metals or alloys, or alumina, zirconia or silica ceramics. The base member 40 includes a generally planar proximal attachment surface 42 structured to engage in surface-to-surface contact with the interface 36 of the prepared trapezium 32. The base member 40 further includes a distal articular surface 44 constructed and adapted to mimic the natural geometry of the saddle 34. In addition to the materials listed above, the implant 38 can be fabricated from zirconium with a coating of zirconium oxide for improved abrasion resistance. The implant 38 can also be formed of zirconium alloys including titanium, niobium, hafnium and other metals known to form stable alloys with zirconium. An anchor means extends from the proximal attachment surface 42 of the base member 40 for anchoring the base member 40 to the trapezium 32. As illustrated in FIGS. 3-5, the anchor means preferably includes at least a pair of spaced posts 46 extending perpendicularly from the proximal attachment surface 42. Each of the posts 46 taper proximally to a pointed tip 48. As shown in FIGS. 3 and 4, the posts 46 are preferably pentahedral, or pyramidal, but also may be conical, tetrahedral, or other simple pointed shape, and have a length substantially less than prior art cylindrical stems. Such short posts 46 allow improved conservation of the trapezium 32, as well as requiring less joint distraction during surgical implantation. During implantation, the pointed posts are self-aligning and readily received into the softer cancellous interior of the resected trapezium 32. Thus, it is unnecessary to prepare receiving pilot holes in the trapezium 32 for the posts 46. For added stability, the proximal attachment surface 42 can be coated with hydroxylapatite or other osteoconductive material prior to implantation. To further aid fixation, the proximate attachment surface 42 can be roughened or made porous to promote bone ingrowth. However, since the joint is under compressive forces at all times, the posts 46 should be adequate to achieve fixation. The distal articular surface 44 of the base member 40 includes a convex medial portion 50, a convex lateral portion 52, and a concave central portion 54 between the medial 50 and lateral 52 portions. This complex curvature of the distal articular surface 44 provides stable support to the adjacent first metacarpal 22 throughout the entire arc of thumb circumduction. Further, this unique and advantageous geometry requires little or no alteration of the normal carpometacarpal joint capsular support. As best shown in FIG. 4, the subject implant 38 includes a perimeter comprising a convex curvature adjacent each of the medial 50 and lateral 52 portions and at least one concave curvature adjacent the central portion 54. In this preferred configuration, the distal articular surface 44 is generally anatomically representative of a natural human trapezium, i.e., one without the degenerative effects of disease or trauma. The perimeter, therefore, comprises a somewhat oval shape having a pronounced jutting end adjacent the lateral portion 52. Therefore, the lateral portion 52 has a greater breadth than the medial portion 50. The medial portion 50 includes a medial crest 58. Likewise, the lateral portion 52 includes a lateral crest 60 which is of greater length, or elevation, than the medial crest 58. Each of the medial 58 and lateral 60 crests define and establish the convex curvatures of the medial 50 and lateral 52 portions, respectively. Therefore, when placed in operation, the proximal articular surface of the first metacarpal 22 seats within the concave central portion 54 and, during circumduction, reacts along the distal articular surface 44 between the medial crest 58 and the lateral crest 60. The natural, anatomically correct, curvature of the distal articular surface 44 enhances articulation of the first metacarpal 22 and thereby provides substantially enhanced comfort, as well as reduced likelihood of abrasion. It will be appreciated that because the base member 40 illustrated in FIGS. 2-5 is substantially anatomically representative of a natural trapezium, right and left base members 40 are required due to the differing, mirror-imaged, bones of the trapezium in the natural human hand. According to a first alternative embodiment of the subject invention as shown in FIGS. 6 and 7, the base member 40' can be constructed in a symmetrical fashion, thereby obviating the need for left and right designations. However, symmetry is achieved at the expense of performance, since the anatomically correct implant 38 shown in FIGS. 2-5 has been found through testing to provide superior results. For convenience, single prime designations are used to represent corresponding elements to those described above. The distal articular surface 44' of the implant 38' shown in FIGS. 6 and 7 includes a perimeter having a generally waisted, or hourglass, oval shape. Thus, as shown in the plan view of FIG. 6, the perimeter takes on a somewhat peanut shell shape. Like the previous shape, the medial portion 50' and lateral portion 52' are each convex and are spaced on opposite sides of a concave central portion 54'. Because of the symmetrical nature of the implant 38' of FIGS. 6 and 7, the elevation of the medial 58' and lateral 60' crests must be equivalent. A second alternative embodiment of the subject implant 38'' is shown in FIGS. 8-10. Double prime designations are used to indicate like or corresponding parts with those discussed above for the sake of convenience. The second alternative implant 38'' has a perimeter shape comprising a continuously convex curvature. As best shown by the plan view of FIG. 9, the parameter has a generally ovoid, or elliptical, shape. The distal articular surface 44'' provides increased surface area in a concave central portion 54'' compared to either of the previous embodiments. And, like the first alternative embodiment of FIGS. 6 and 7, the implant 38'' is symmetrical so that left and right designations are not required. The subject trapezial implant 38, 38', 38'' shown in the Figures overcomes the disadvantages of the prior art by means of an anatomically-correct distal articular surface 44 providing stable support to the adjacent first metacarpal 22 throughout the entire arc of thumb circumduction. As a result, fewer wear particles are generated using implants of the invention than obtained with prior art prostheses. This invention permits material selection for the implant 38 to include hard, abrasion-resistant metals, alloys and ceramics rather than softer elastomers. Further, the anchor means is specifically structured to reduce joint distraction during implantation, further allowing improved conservation of the bone of the trapezium 32. Therefore, the subject implant 38 is easier to install than prior art implants. Although description of the preferred embodiment has focused upon the location of the implant 38 upon the distal trapezium 32, it will be readily appreciated by those skilled in the art that equally successful results can be obtained when the implant 38, or one of the alternative implants 38', 38'', is located in other small joints of the body, e.g., the finger or toe joints. The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

A trapezial implant is provided for attachment to the trapezium of a hand. The implant includes a base member fabricated from an inelastic material such a medical grade metal or ceramic. The base member includes a generally planar proximal attachment surface from which extend two pentihedral-shaped spikes. The base member also includes a distal articular surface having a non-symmetrical, complex curvature. The implant is retained in place on the trapezium under compression of the first metacarpal.

FIELD OF THE INVENTION [0001] The present invention relates generally to a system and method of providing interactive content to a broadcast program display to enhance the viewing experience of a viewer of the broadcast program. More particularly, the present invention concerns determining the nature of a broadcast program being viewed by a user and the location of the person viewing the broadcast content, in order to access a source of interactive content over a computer network, perform a search of the interactive content source while applying rules affecting the search to retrieve any interactive content associated with the broadcast program being viewed by the user, and to coordinate transmission of any retrieved interactive content to the viewer and display of the interactive content on a viewer display under the control of the viewer. BACKGROUND OF THE INVENTION [0002] Prior art systems are known which integrate television broadcasts with other video or audio content such as a stream of data broadcast over the internet. Although such merged displays may be interactive, they require action on the part of the broadcast program provider and cannot be dynamically created and controlled by alternate uncoordinated content providers or a community of viewers or an individual viewer of a broadcast program. SUMMARY OF THE INVENTION [0003] Accordingly, the present invention provides a system and method of displaying interactive content relevant to a broadcast presentation on a viewer display associated with a viewer device. The method begins with the receipt, at the viewer device, of a broadcast presentation from a broadcast presentation provider. Next, the viewer device receives relevant interactive content from a source of interactive content, filtered and characterized for a specific user. This additional content is bound to the broadcast content only by nature of a relevancy mapping. As such, it may be presented to the user without the broadcast content providers direct assistance, intervention or even knowledge. [0004] The viewer device merges the broadcast presentation and the filtered and characterized relevant interactive content and displays both the broadcast presentation and the relevant interactive content on a viewer display. Preferably, the viewer device accesses the source of relevant interactive content over a computer network, such as the Internet. [0005] The method of searching and retrieving identified interactive content relevant to said identified broadcast presentation utilizes a dynamically programmable and interdependent rule system including at least one rule from a group including, for example, a rule limiting content to specific broadcast programming; a rule limiting content to authorized users; a rule limiting content to user affinity with an identified group of authorized users; a rule limiting content to a specific geographical location; and a rule limiting content to broadcaster permission. The dynamically programmable and interdependent rule system typically would operate automatically without user or viewer intervention. DESCRIPTION OF THE DRAWINGS [0006] The present invention will be better understood by reading the following detailed description, taken together with the drawings wherein: [0007] [0007]FIG. 1 is a schematic diagram of one exemplary system embodying the principles of the present invention, wherein a viewer of a broadcast program accesses a source of interactive information associated with the broadcast program over a computer network; [0008] [0008]FIG. 2 is diagram showing the multiple layers that are displayed on a viewer display device; [0009] [0009]FIG. 3 shows a converged display including the multiple layers of FIG. 2, including a background layer for displaying a broadcast program and an interactive content overlay layer; [0010] [0010]FIG. 4 shows an alternative display strategy for windowing multiple sources of information on a display device; and [0011] [0011]FIG. 5 is a flow chart of one exemplary method of providing interactive content to a broadcast program. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0012] A system 10 , FIG. 1, on which the present invention can be utilized and which embodies the present invention, includes a multi-media presentation system 12 maintained by a system user. (The term user and viewer will be used interchangeably in the remainder of this description and should be construed to mean a person who perceives a broadcast presentation using his or her senses, including but not limited to sight and/or hearing.) The term multi-media presentation system is used herein to indicate a system capable of presenting audio with or without video information to a user. However, the presentation of more than one media should not be construed as a limitation of the present invention. Examples of such multi-media presentation systems 12 include personal computer (PC) systems, PC televisions (PCTVs), televisions used in combination with set-top boxes, and the like. [0013] Each multi-media presentation system or workstation 12 includes a viewer computer 14 and at least one viewer display device 16 , such as a computer monitor or television set. Each multi-media presentation system 12 also includes at least one input device 18 , such as a keyboard, mouse, digitizer pad, writing pad, microphone, camera or other pointing or input generating device which allows the user to provide user input the workstations 12 . [0014] As will be described more fully below, each multi-media presentation system 12 is adapted to receive at least one broadcast presentation signal 20 , which may be provided in the form of broadcast television programming (including standard broadcast television received with an antenna, cable and satellite television), closed circuit television, Internet web-TV or a broadcast like signal received from a device such as a storage device (hard drive, DVD, CD ROM), cassette tape, VCR tape or the like, received by means of a standard television broadcast signal over the air waves, cable television or satellite television, utilizing a tuner or other method in each viewer computer 14 . [0015] In addition, in one preferred embodiment, each multi-media presentation system 12 interfaces with a computer network 40 , which may be provided in the form of a local area network (LAN), a wide area network (WAN), a telephone (wireless) network or a global computer network, such as the Internet running a communication protocol such as Internet Protocol (IP). [0016] The heart of the multi-media presentation system 12 is the viewer computer 14 . Each viewer computer 14 includes a central processing unit (CPU) 22 , which controls the functions of the presentation system. The CPU 22 interfaces a broadcast receiver 24 , which is associated with the viewer computer 14 . The broadcast receiver 24 receives, as its input, the broadcast program signal 20 . In one embodiment, the broadcast receiver 24 is a broadcast channel tuner that receives broadcast signals from a source such as a television broadcasting station or other programming provider or source. [0017] In another embodiment, the broadcast receiver 28 is a PC tuner card included in the viewer computer, which provides television functionality to the viewer computer 14 . In another embodiment, the broadcast receiver is an IP enabled device (such as a cable modem) attached or integrated with the viewer computer 14 . [0018] Each viewer computer 14 also includes a communication controller 26 to control inputs received from, and outputs transmitted to, the computer network 40 . In one preferred embodiment, the communications controller 26 may include a device such as a modem (for example, a telephone or cable modem) or a network interface card that receives information from a local or wide area network. [0019] Each viewer computer 14 may also include internal storage 28 , such as memory, disk drive, CD-Rom, tape or the like, where information relevant to a displayed broadcast presentation may be stored. [0020] A dynamic display controller 30 (also known as a broadcast browser) is also provided with each viewer computer 14 . The dynamic display controller 30 interfaces the CPU 22 , broadcast receiver 24 and communications controller 26 and system storage 28 and receives, as input, a broadcast presentation in the form of broadcast signal 20 , information stored in system storage 28 and additional information from the computer network 40 (via the communication controller 26 ). The dynamic display controller 30 merges the multiple input signals and outputs a merged data signal to the display device 16 . [0021] In the preferred embodiment of the present invention, which is disclosed for illustrative purposes only and not considered a limitation of the present invention, the dynamic display controller 30 is implemented as computer software in the form of a browser user interface operating on the viewer computer 14 , which is a personal computer or individual computer workstation. [0022] Each multi-media presentation system 12 also includes at least one input device 18 , which allows a viewer to provide input to the dynamic display controller 30 , which will be explained in greater detail below. [0023] In the exemplary embodiment of FIG. 1, a source of interactive content 42 is accessible to the multi-media presentation system 12 via the computer network 40 . In the illustrative example, the source of interactive content 42 includes an interactive content database 44 that is controlled by a remote, interactive content server 46 . In this embodiment, when a viewer is viewing a broadcast presentation 20 on his or her display device 16 , he or she may also, simultaneously, view interactive content that is relevant to the broadcast presentation 20 being viewed. [0024] In order to ensure that the interactive content is, in fact, relevant to the broadcast presentation, information identifying and characterizing the broadcast presentation must be provided to the interactive content server 46 . The present invention contemplates a number of means by which such identifying and characterizing information can be provided to the interactive content server. For example, a viewer may provide identifying information to his or her viewer computer 14 using input device 20 . [0025] Alternatively, the CPU 22 querying the broadcast receiver 24 to identify the source of the broadcast signal 20 being viewed may identify the broadcast presentation being viewed. The CPU may then determine from the date and time, that the particular broadcast presentation 20 is being viewed and the source of the broadcast, including the identity of the broadcast presentation. In another example, a location of the viewer's computer, coupled with the date, time and received channel can be used to identify the broadcast presentation being viewed. Location information can be obtained by, for example, a zip code input provided by the viewer to the viewer computer via input device 18 , a GPS receiver attached to the viewer computer, or a local transmitter identifier such as could be provided by a cell phone network transmitter. [0026] Once the broadcast presentation is identified, an identifier is provided to the source of interactive content, such as the interactive content database 44 via the interactive content server 46 and computer network 40 . When the interactive content server 46 receives the identifying information for the broadcast presentation being viewed, it will search the interactive content database 44 while applying rules affecting the search and retrieve any interactive content that is relevant to the identified broadcast presentation. [0027] In the embodiment of FIG. 1, the source of interactive content is accessed over a computer network and preferably, the Internet. Thus, any viewer computer that is capable of transmitting and receiving information in hypertext transfer protocol (http) can access the source of interactive content 42 over the Internet. Though the http protocol is used for illustrative purposes, the usage of alternate protocols, including protocols not yet developed, is envisioned in future embodiments and considered within the scope of the present invention. [0028] Once retrieved, filtered and characterized for the particular user, the relevant interactive content is then provided, from the interactive content source 42 , to the viewer computer 14 , where the communication controller 26 receives it. The dynamic display controller 30 thereafter merges the received relevant interactive content with the broadcast presentation and displays both on the viewer display 16 . [0029] [0029]FIGS. 2 and 3 show an example of one display strategy that may be utilized by the dynamic display controller 30 . Such a layering or “overlay” strategy may utilized by the dynamic display controller 30 to control the display of the broadcast presentation and the filtered and characterized relevant interactive content so that all of the data may be displayed in a single window or screen on each display device 16 for a given user or viewer. [0030] The dynamic display controller 30 displays the broadcast presentation in a “background” layer 50 . Next, an overlay is displayed in the same window in at least one additional layer 54 on top of the background layer 50 . (It is understood that the order or layers can be reversed, if desired.) In order to allow the broadcast signal in the background layer 50 to be visible through the second layer 54 , the second layer utilizes a substantially transparent background 56 or, as is disclosed herein, a background referred to by name as “broadcast” to signify the source of the background information. [0031] In one embodiment, the dynamic display controller 30 may automatically display, in at least one of the additional layers 54 , the filtered and characterized relevant interactive content 58 that it received from the interactive content source 42 , in this example over computer network 40 . Examples of interactive content include additional information regarding a product being displayed in the broadcast presentation, information regarding characters or actors or actresses appearing in the broadcast presentation and the like, all such content filtered and targeted for the particular viewer based or various criteria, as set forth above. [0032] Relevant interactive content 58 could also include information allowing a viewer of the broadcast presentation to affect a purchase of an item that is being displayed in the broadcast presentation. In such a case, in addition to providing the relevant interactive content, input can be solicited from the viewer in one or more viewer input window 62 (FIG. 4). [0033] In another embodiment, an interactive content icon 60 may also be provided and will appear when interactive content is available to allow a viewer to control when and if relevant interactive content is to be displayed on his or her display device 16 during a broadcast presentation. Thus if a viewer wishes to enhance his or her viewing experience, he or she can activate the display of relevant interactive content by selecting the interactive content icon 62 . Conversely, if a viewer believes that interactive content would hinder his or her viewing experience, he or she can prohibit the display of interactive content by de-selecting the interactive content icon 62 . [0034] The embodiment of FIG. 4 utilizes a different display strategy than the embodiment of FIG. 3. In this embodiment, instead of using a layered display strategy, a windowed strategy is used. In the windowed strategy, the dynamic display controller displays the broadcast presentation 20 is a first window 64 . Any retrieved relevant interactive content is then displayed in at least one additional window 66 . Of course, multiple additional windows may be utilized. [0035] For example, a first additional window may be provided to provide relevant interactive content about a product or service. The first additional window may have user-selectable icons that could trigger the display of a second or subsequent additional window if additional information or interaction between the viewer and the interactive content source is desired, such as, for example if a viewer wishes to purchase a product or service. Of course, each window may be sized and positioned in order to optimize the display of all of the information on the display device. [0036] A method 100 of displaying interactive content relevant to a broadcast presentation on a viewer display is shown in FIG. 5. In order to utilize the method, a viewer will have a viewer computer that is capable of receiving a broadcast presentation. For example, a viewer may have a personal computer, PC TV or a set-top box associated with his or her television. Each viewer computer will include a display controller for controlling a display device and, in the preferred embodiment, a communication controller for interfacing the viewer computer with a source of interactive content over a computer network. However, the invention contemplates the use of other sources of interactive content, including a database that is included in storage of the viewer computer, in which case, a communication controller would not be required. [0037] The method 100 begins by receiving a broadcast presentation at the viewer computer, act 110 . Next, in act 120 , relevant interactive content is also provided to the viewer computer. Then, in act 130 , the broadcast presentation and interactive content are merged by a dynamic display controller and are displayed on a display device. [0038] In the preferred embodiment, the viewer computer accesses a remote source of interactive content over a computer network. Since the source of interactive content is envisioned to be made available to any viewer computer that can access the computer network, a method of ensuring that only interactive content that is relevant to the broadcast presentation and appropriate to the user is provided to the viewer computer for display. To ensure that only relevant interactive content is displayed, the broadcast presentation must first be identified, act 122 . For example a viewer may simply provide information to his or her viewer computer identifying the broadcast presentation. [0039] Alternatively, the viewer computer can automatically or semi-automatically identify the broadcast presentation being viewed by monitoring the source of the broadcast presentation (e.g. television channel being viewed) along with the date, time and geographic location of the viewer (e.g. using zip code or other geographically specific information previously entered/stored or dynamically determined on the viewer's display system). In the case of cable television broadcasting, viewing date, time and cable provider may provide sufficient information to identify the broadcast presentation. [0040] Once the broadcast presentation is identified, then, in act 124 , a source of interactive content is searched to identify any interactive content relevant to the broadcast presentation. If relevant interactive content is identified, then it is retrieved from the interactive content source and transmitted to the viewer computer, act 126 , preferably over a computer network, such as the Internet. [0041] The method 100 optionally allows for viewer interaction with the interactive content, act 140 , by, for example providing information to the interactive content source using one or more input device. Any input information would then be transmitted to the interactive content source over the computer network. [0042] Accordingly, the disclosed invention provides a system and method of providing and displaying, on a viewer's display device, interactive content that is specifically relevant to a broadcast presentation and to a particular viewer. [0043] Modifications and substitutions by one of ordinary skill in the art are considered to be within the scope of the present invention, which is not to be limited except by the claims that follow.

A system and method of displaying interactive content relevant to a broadcast presentation on a viewer display associated with a viewer device. The method begins with the receipt, at said viewer device, of a broadcast presentation from a broadcast presentation provider. Next, the viewer device receives relevant interactive content from a source of interactive content, filtered and characterized for a specific user. This additional content is bound to the broadcast content only by nature of a relevancy mapping. As such, it may be presented to the user without the broadcast content providers direct assistance. The viewer device merges the broadcast presentation and the relevant interactive content and displays both the broadcast presentation and the relevant interactive content on a viewer display. Preferably, the viewer device accesses the source of relevant interactive content over a computer network, such as the Internet.

CROSS-REFERENCE TO RELATED APPLICATION This application claims priority of Taiwanese Patent Application No 100211994 filed on Jun. 30, 2011 BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a mortise lock, and more particularly to a mortise lock with high resistance against destructive external pulling forces. 2. Description of the Related Art A mortise lock typically includes a latch unit that includes a deadbolt and a live bolt and that can be operated through a key lock or an exterior handle at an outside of a door, or through a rotary button or an interior handle at an inside of the door. The key lock is formed with an external screw thread, and the latch unit has a threaded hole to receive the key lock and to engage the external screw thread. For installation in a door panel, the latch unit is disposed in a latch hole disposed within the door panel and opening at a side face of the door panel, and the key lock is inserted into the threaded hole of the latch unit through a lock hole formed in an outer face of the door panel. The exterior handle is attached to an exterior-cover and the exterior cover is attached to, an outside face of the door panel. The interior handle is attached to an interior cover, and the interior cover is disposed on an inside face of the door panel and is connected to the exterior cover. An example of such a mortise lock is disclosed in U.S. Pat. No. 7,152,442. Generally, conventional mortise locks have no interlocking means to interlock the key lock with the exterior cover. Because retention of the key lock is mainly relied on an engagement between the screw thread of the key lock and the threaded hole in the latch unit, there is no sufficient resistance against external pulling forces, and the key lock can be easily removed from the door panel by burglars using destructive forces to violently pull the key lock and to destroy the screw thread thereof for separation of the key lock from the threaded hole of the latch unit. SUMMARY OF THE INVENTION An object of the present invention is to provide a mortise lock with high structural strength to resist against destructive external pulling forces. According to one aspect of the present invention, a mortise lock mountable on a door panel, comprises: a latch unit having a key lock hole; an exterior cover having a base plate portion, an aperture formed in the base plate portion in alignment with the key lock hole, amounting post projecting inwardly from an inner surface of the base plate portion, and a peripheral wall that projects inwardly and laterally from the base plate portion to surround the aperture and the mounting post; a key lock that is disposed in the aperture and the key lock hole, that is interlocked with the key lock hole, and that has an outer periphery formed with a first engaging part; and a reinforcing plate mounted on the mounting post and disposed around the key lock. The reinforcing plate includes a notch that receives the key lock, and a second engaging part disposed in proximity to the notch to engage the first engaging part. The reinforcing plate abuts against the base plate portion and has a lateral flange that projects inwardly away from the base plate portion and that has an inner end substantially flush with an inner end of the peripheral wall of the exterior cover. The lateral flange is adapted to abut against the door panel. According to another aspect of the invention, a mortise lock comprises: a latch unit having a key lock hole; an exterior cover having a base plate portion, an aperture formed in the base plate portion in alignment with the key lock hole, a securing post projecting inwardly from an inner surface of the base plate portion, and a peripheral wall projecting inwardly and laterally from the base plate portion and surrounding the aperture and the securing post; a key lock extending through the aperture and interlocked with the key lock hole; a securing plate mounted on the securing post, and having a securing post hole disposed around the securing post, and a transmission rod hole; an exterior handle attached to the exterior cover; a torsional returning unit having a main body that is mounted on the securing post and that is disposed between the exterior cover and the securing plate, and a cam member that projects from the main body to the securing plate; and a transmission rod connected to the exterior handle to actuate the latch unit and extending through the cam member and the transmission rod hole. The securing plate has an outer side engaging the main body and an inner side adapted to engage the door panel. According to still another aspect of the invention, a mortise lock comprises: a latch unit having a key lock hole; an exterior cover having a base plate portion, an aperture formed in the base plate portion in alignment with the key lock hole, a pair of mounting posts and a pair of securing posts, all of which project inwardly from an inner surface of the base plate portion, and a peripheral wall projecting inwardly and laterally from the base plate portion and surrounding the aperture and the mounting and securing posts; a key lock disposed in the aperture and the key lock hole, interlocked with the key lock hole, and having an outer periphery that is formed with a first engaging part; and a reinforcing plate mounted on one of the mounting posts, disposed around the key lock and abutting against the base plate portion. The reinforcing plate includes a notch that receives the key lock, a second engaging part disposed in proximity to the notch to engage the first engaging part, and a lateral flange projecting inwardly away from the base plate portion and having an inner end substantially flush with an inner end of the peripheral wall of the exterior cover. The lateral flange is adapted to abut against the door panel. The mortise lock, further includes an exterior handle attached to the exterior cover; a torsional returning unit that has a main body mounted on the securing posts, and a cam member projecting from the main body; and a transmission rod connected to the exterior handle to actuate the latch unit and extending through the cam member. BRIEF DESCRIPTION OF THE DRAWINGS Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment with reference to the accompanying drawings, of which: FIG. 1 is a perspective view illustrating a preferred embodiment of the mortise lock according to the present invention mounted on a door panel; FIG. 2 is an exploded view of the preferred embodiment; FIG. 3 is an exploded view showing an exterior lock unit of the preferred embodiment; FIG. 4 is a perspective view of a securing plate of the preferred embodiment; and FIG. 5 is a sectional view of the preferred embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 to 5 , a mortise lock according to a preferred embodiment of the present invention is mountable on a door panel 4 and includes a latch unit 1 , an exterior lock unit 2 and an interior lock unit 3 . The exterior lock unit 2 , includes an, exterior cover 21 , a key lock 22 , a reinforcing plate 23 , a securing plate 24 , a torsional returning unit 25 , a transmission rod 26 , and an exterior handle 27 . The door panel 4 has a latch hole 45 formed through a side face of the door panel 4 . A key lock hole 41 , a transmission rod hole 42 , two first installation holes 43 , and four second installation holes 44 are formed through an outer face of the door panel 4 . The latch unit 1 is installed in the latch hole 45 and has a key lock hole 11 with an internal thread 111 . The latch unit 1 has a deadbolt 11 and a live bolt 12 . Since the construction of the latch unit 1 is known and is not detailed hereinafter. The key lock 22 has an outer periphery formed with a threaded portion 222 and two first engaging parts 221 . The first engaging parts 221 are preferably configured as engaging grooves. The threaded portion 222 passes through the key lock hole 41 in the door panel 4 and is engaged with the internal thread 111 of the key lock hole 11 in the latch unit 1 . The exterior cover 21 includes a base plate portion 211 formed with an aperture 219 . Two internally threaded mounting posts 215 and two internally threaded securing posts 216 project inwardly front an inner surface of the base plate portion 211 . A peripheral wall extends inwardly and laterally from the base plate portion 211 and includes two sidewalls 212 , an upper wall 213 , and a lower wall 217 . The peripheral wall surrounds the aperture 214 , the mounting posts 215 and the securing posts 216 . The reinforcing plate 23 has an upper edge 234 , a lower edge 231 , two opposite sides that interconnect the upper edge 234 and the lower edge 231 and that are formed respectively with lateral flanges 232 , a mounting post hole 233 formed between the upper edge 234 and the lower edge 231 , a notch 236 indented upwardly from the lower edge 231 , and two opposite second, engaging parts 235 formed in proximity to the notch 236 . The notch 236 receives the key lock 22 . The second engaging parts 235 are engaging edges that bound the notch 236 and that respectively engage the first engaging parts 221 of the key lock 22 . The mounting post hole 233 is disposed around one of the mounting posts 215 proximate to the upper wall 213 . An outer surface of the reinforcing plate 23 abuts against the base plate portion 211 . The lateral flanges 232 of the reinforcing plate 23 project inwardly away from the base plate portion 211 . The upper edge 234 and the lateral flanges 232 respectively abut against the upper wall 213 and the sidewalls 212 of the exterior cover 21 . The lateral flanges 232 are substantially parallel to the sidewalls 212 and have inner ends that are substantially flush with inner ends of the side walls 212 and that are adapted to abut against the door panel 4 . The torsional returning unit 25 has a four-sided main body 250 that has four sides 253 , a cam member 251 rotatably mounted to the main body 250 , a cam hole 254 formed in the cam member 251 , and four lateral through holes 252 formed around the cam hole 254 . The main body 250 is mounted on the securing posts 216 and is disposed between the exterior cover 21 and the securing plate 24 . Two of the lateral through holes 252 are disposed around the two securing posts 216 , respectively. The exterior handle 27 is attached movably to the exterior cover 21 . The securing plate 24 has two spaced apart clamp parts 241 protruding from the securing plate toward the main body 250 , a transmission rod hole 245 formed between the clamp parts 241 , two spaced apart bosses 243 protruding from the securing plate 24 and arcuated to extend around the transmission rod hole 245 , two spaced apart recesses 247 arcuated to extend around the transmission hole 245 oppositely of the bosses 243 , and stop elements 246 formed within the recesses 247 . The bosses 243 protrude into the transmission rod hole 42 in the door panel 4 so that the inner side of the securing plate 24 is in engagement with the door panel 4 . The cam member 251 is received rotatably in the recesses 247 . Each recess 247 has two angularly spaced apart shoulders which serve as the stop elements 246 . The stop elements 246 function to limit a rotation angle of the cam member 251 . Preferably, the securing plate 24 is a stamped plate that has a bent area to form the bosses 243 , the recesses 247 , and the stop elements 246 . An inner surface of the bent area is protruded inwardly to form the bosses 243 , and an outer surface of the bent area is indented to form the recesses 247 . The main body 250 of the torsional returning unit 25 has two opposite sides 253 respectively abutting against the sidewalls 212 of the exterior cover 21 , and two other opposite sides 233 clamped by the clamp parts 241 of the securing plate 24 . The main body 250 is therefore in engagement with an outer side of the securing plate 24 . The securing plate 24 further has four securing post holes 242 , and a mounting post hole 244 . Two of the securing post holes 242 are disposed around the securing posts 216 , respectively. The mounting post hole 244 is disposed around the mounting post 215 proximate to the lower wall 217 . The transmission rod 26 has one end connected to the exterior handle 27 . The transmission rod 26 is also connected to the cam member 251 and extends through the cam hole 254 of the cam member 251 . The transmission rod 26 is inserted into the latch unit 1 through the transmission rod hole 245 in the securing plate 24 and the transmission rod hole 42 in the door panel 4 . The latch unit 1 can therefore be actuated by the transmission rod 26 . The interior lock unit 3 includes an interior handle 33 , an interior button 32 , an interior cover 31 , a securing plate 34 and a torsional returning unit 35 . The construction of the securing plate 34 and the torsional returning unit 35 is the same as that of the securing plate 24 and the torsional returning unit 25 of the exterior lock unit 2 . Two screws 28 and two screws 29 are used to secure the interior lock unit 2 to, the mounting posts 215 and the securing posts 216 , respectively. In use, the deadbolt 11 may be actuated by operating the key lock 22 at an outside of the door panel 4 or by operating the rotary button 32 at an inside of the door panel 4 . The live bolt 12 may be actuated by operating the exterior handle 27 or the interior handle 33 . With the reinforcing plate 23 which is disposed in abutment with the base plate portion 211 of the exterior cover 21 and which has lateral flanges 232 to abut against the door panel 4 , the mortise lock of the present invention possesses high structural rigidity and robustness. The structural rigidity of the mortise lock is further increased by the securing plate 24 that is mounted on the securing posts 216 in abutment with the torsional returning unit 25 and the door panel 4 . While the present invention has been described in connection with what is considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.

A mortise lock is provided with a reinforcing plate to enhance structural rigidity and robustness for resistance against external destructive pulling forces. The reinforcing plate is disposed in abutment with an exterior cover and a door panel, and is mounted on a mounting post of the exterior cover. The reinforcing plate has a notch to receive and engage a key lock. A securing plate may be disposed between and in abutment with the door panel and a main body of a torsional returning unit which is connected to an exterior handle to further increase structural rigidity.

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a divisional of 10/171,721 flied Jun. 14, 2002, now U.S. Pat. No. 6,767,147. STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT (Not Applicable) BACKGROUND OF THE INVENTION Dot matrix printer assemblies utilize ribbon cartridges that contain continuous strip of material impregnated with an ink solution. The ribbon is contained in a cartridge container that normally mounts around the dot matrix printer's print head. As the ribbon passes between the printer head and a sheet of paper, information is then printer on to the sheet of paper. In order to print the information, small rods or pins in the printer head are thrust into the ribbon, which then makes contact with the paper adjacent to the pins, thereby transferring ink from the ribbon to the paper. Through the proper combination of dots, the ink transferred is transformed into recognizable letters or symbols. The higher the impact force of the pins on the ribbon the darker the resulting image. Contemporary printers commonly produce a consistent impact force. As the printer assembly moves across the sheet of paper, the ribbon formed as a continuous band, is also pulled laterally across the gap between the paper and the print head, continuously providing a new area to be struck by the pins in order to provide ink for the printing operation. If the ribbon did not continuously move, it would quickly wear out in response to repetitive striking of the same area. At present, many pictures such as dot matrix printers, do not track ink usage. The user typically notices print cartridge deficiency only when the printer starts printing characters that are difficult to read. As a matter of practicality, it will often be the case that a replacement is not readily available. For a business, this often means extra cost incurred in the form of expedited shipping charges. A second factor in obtaining optimum print quality and usage efficiency from an ink ribbon cartridge is the variations in print quality attributable to differences in the manufacture and type of ribbon. Competitive pressures cause some suppliers to use lower quality ribbon or inks, which may produce lighter images. In such cases the user may assume the problem is with the printer and not the ribbon. Previous methods for determining the type of cartridges have included physical extrusions or indentations on the cartridge so that the printing unit can determine which cartridge model is being utilized. This has a limitation in that all of the possible permutations much be considered at the start of the program, in order to modify the tooling for the cartridge body and the sensors in the printing unit. By contrast to prior art dot matrix printers, prior art laser printers have employed advanced systems for identifying cartridge mode. One such system is disclosed by U.S. Pat. No. 5,289,242 entitled “METHOD AND SYSTEM FOR IDENTIFYING THE TYPE OF TONER PRINT CARTRIDGES LOADED INTO ELECTROPHOTOGRAPHIC PRINTERS” issued to Christensen, et al. A metal label is installed on the print cartridge, and contacts in the laser printer are used to detect and connect the metal label to a DC voltage signal line. If there is no conductive metal strip, then the detected voltage level is at logic 1, or 5 volts. If there is a conductive metal strip, then detected voltage is at logic 0, or 0 volts. By passing current through the label and determining the results, the printer ascertains what type of cartridge is installed. This system has the disadvantage that may not distinguish many types of cartridges. Moreover, if the label is dirty or improperly positioned, failure to detect cartridge type will result in assumption by the printer that no cartridge is installed, and thus the printer will not work. Furthermore, this system is inappropriate for dot matrix printers. The primary advantage of dot matrix printers over, for instance, laser printers is that both the printer and the ink cartridges are relatively inexpensive. The metal label component could be prohibitively expensive if applied to a dot matrix print cartridge. A method and apparatus are provided for adaptively controlling printer functions of a dot matrix printer in response to sensing the type of printer ink cartridge being used. An identifying resistive value is applied to surface of the cartridge and installed within the printer. The printer includes contacts that include sensors and sensor circuitry useful to detect a presence of the resistive indicator, and the resistive value thereof. The sensed resistive value is used to directly control printer functions, and/or to access stored data or printer control routines specific to the type of cartridge, or desired performance characteristics. Stored information, which may be appended by other sensed information such as printer usage data, is used to selectively regulate printer operation to achieve maximum efficiency and performance from the particular ink cartridge. The resistive indicator may be applied directly to a surface of the cartridge, or to a label that may be adhesively applied to the cartridge, to facilitate compatibility with different cartridges. In some cases a cartridge may support different labels, each conforming a to a different operational status of the printer. By means of the present invention, information respecting one or more characteristics of the ink cartridges can be adaptively factored into printer operation in order to enhance image quality and to enhance the operational life of the ink cartridge. A display will and/or alarm may be incorporated into the invention to provide a visual indication of the printer/ink cartridge status, remaining life or ink cartridge, and other data. The resistive ink identifier may be formed in different ways, to provide different resistive values corresponding to operational parameters. In one embodiment the resistive ink identifier has a resistance value that is a function of its length. In other embodiments the resistive value of the ink identifier is a function of its width, or ink characteristics. In the presently preferred embodiment print head impact force may be regulated, in response to sensed resistive values by varying the pulse width of the print head activation coil. As would be apparent to those with ordinary skill in the yard, various other methods may be used to regulate functions such as printer impact force, without departing from the broader aspects of the invention, as set forth below. BRIEF DESCRIPTION OF THE DRAWINGS These as well as other features of the present invention will become more apparent upon reference to the drawings wherein: FIG. 1 is a view of a print cartridge designed in accordance with the present invention; FIG. 2 a is a view of a label with a resistive ink identifier; FIG. 2 b is a view of a label with an alternate resistive ink identifier; FIG. 3 is a view of a print cartridge designed in accordance with the present invention. FIG. 4 a is a diagram of a basic implementation of sensor/regulation circuitry in a printer designed in accordance with the present invention. FIG. 4 b is a diagram of a more advanced implementation of sensor/regulation circuitry in a printer designed in accordance with present invention; FIG. 5 is a view of a striker of a dot matrix printer; FIG. 6 is a graph showing how the strike force of the striker can be modified by changing pulse width; FIG. 7 is a block diagram illustrating the method of using the sensor/regulation circuitry of FIG. 4 a; FIG. 8 is a block diagram illustrating a basic method of using the sensor/regulation circuitry of FIG. 4 b. FIG. 9 is a block diagram of an advanced method of using the sensor/regulation circuitry of FIG. 4 b. DETAILED DESCRIPTION OF THE INVENTION In accordance with the present invention there is provided a device and method for sensing the presence and type of cartridge installed in a dot matrix printer and for modifying printer functionality in response to the sensed information. In order to distinguish between different ink ribbon cartridge models, it is cost efficient to use only one sensor or one sensor set, and still permit the usage of many different ribbon ink cartridge models. An electronic component, mounted upon the cartridge exterior services to identify and distinguish the cartridge model but manufacturing cartridges including such a component would be expensive. Besides the cost of the component itself, contact areas would also have to be installed. However, if the component were in the presently preferred embodiment, the electronic component or indicia is implemented as a resistor, silk-screened directly on the cartridge exterior or onto a printed resistor label the resistance value is used to signify, for example, the cartridge model and ribbon characteristics, such as ribbon type, length, ink density, etc. Where no resistor is sensed, for instance because an unclassified cartridge was installed, the cartridge would still function using default values not optimized values for printing. The silk-screened resistor could be silk-screened directly onto the cartridge at any convenient location. It could also be silk-screened onto a label that would be placed on the cartridge prior to shipment. The ability to add the resistor at any time would permit any cartridge presently in use to be classified and employed in connection with the present invention. In the presently preferred embodiment of the present invention, the printer sensor is implemented by a simple pair of contacts which, when touching he silk-screened resistor, can be used to determine the resistance value of the resistor. The value of the silk-screened resistor is compared to a value stored in memory of the printing unit. The stored values are defined for known models and can also define extrapolated future models. The resistance value could be used to regulate printer striking force, specify the number of characters that can be printed from the ribbon (length/type of ribbon), the amount of ink density or remaining ink on the ribbon, etc. Different resistive values may be applied by varying the material used to fabricate the resistor, i.e. the use of different conductivity/resistivity materials. Alternatively, resistor paths lengths can be varied to produce different resistances while using the same conductivity materials. In another implementation different resistor values are obtained by varying the length to width ratio of the resistor materials, as such, one of ordinary skill will recognize that technique for applying resistive indicators of various resistor values, may vary, dependant upon cost, ease of application, etc. A color-coding scheme would also be provided, so that the customer could more easily distinguished between and select different capacities for the tape ribbon cartridge by the resistor color. Printer control circuitry can be used and optimized to vary the applied printing force for improved quality of readability. Printing force can be varied in response to contact factors, such as ribbon type, ribbon length and ink density. Printing force can also be varied in response to additional sensed parameters, such as ongoing ribbon usage (ribbon advance). Printer control circuitry can also implement stored programs to selectively implement other functions, as most efficient for the sensed cartridge. For example, by knowing the type and capacity of the ribbon, and number of characters already punched, the remaining capacity of the particular cartridge can be known. As the ribbon is reaching the end of its ink supply, the time between pin strikes could also be lengthened to make the printed characters remain dark for longer, thereby increasing the life of the ink ribbon cartridge. A LCD display can be used to display the remaining life of the ink ribbon cartridge and provide a visual and/or audio indication when the ink life is below a certain level. The level can be either stored or generated as the cartridge ink is being used, thereby providing an advance warning to the operator. As the ribbon cartridge is changed, the counter can be automatically zeroed. Referring now to the drawings, FIG. 1 is a view of an exemplary ink cartridge designed in accordance with the present invention. Housing 1 contains the unexposed portion of the ribbon 3 as well as mechanisms (not shown) for cycling the ribbon through the exposure area 5 . A label 7 if affixed to the housing 1 . The label includes a resistive ink identifier 9 . Alternatively, the resistive ink identifier 9 could be affixed directly to the housing 1 . In a preferred embodiment of the invention, the resistive ink identifier is a silk screened conductive ink. The silk-screened conductive ink has the advantage of being cheap and easy to apply. FIGS. 2 a and 2 b illustrate how the resistive value of the resistive ink identifier can be varied by altering the length of the resistive ink identifier. In FIG. 2 a , the resistive ink identifier 11 follows the shortest possible path between the two contact points 13 and 15 . This resistive ink identifier 11 will therefore have a relatively low resistive value. In FIG. 2 b , the resistive ink identifier 17 follows a relatively longer path between the two contact points 19 and 21 . This resistive ink identifier 17 will therefore have a higher resistive value than the resistive ink identifier 11 of FIG. 2 a. Resistance may be measured in ohms/square, and resistances range from less than one ohm/square to thousands of ohms/square. The resistance of an inked path is the product of the squares and the ohms/square. For example, a path of length L may be a total resistance of 1000 ohms. If the path were made twice as long or ½ as wide, the resistance would be 2000 ohms. The resistance would also become 2000 ohms if the ohms/square of the resistive material was doubled. By assigning ink cartridge characteristics to different resistive values, the resistive value of the resistive identifier can be used to represent those characteristics. For instance, the resistive value of the restive ink identifier may be used to access information representative of various physical characteristics of the ink ribbon in the ink cartridge such as the length of the ribbon, the ink density of ink, the ribbon or optimum impact force. Alternatively, a ratio could be assigned between resistive value and total ink capacity. In the latter case, the resistive value would correspond directly to the ink capacity of the ink cartridge, the ink capacity could be measured by various means, but would probably be measured by an estimated number of characters that can be printed. As an additional feature, the resistive ink components may be color coded for convenient identification by a human user. FIG. 3 illustrates an exemplary ink cartridge 23 ; designed in accordance with the present invention, installed into a dot matrix printer. In this view, it can be seen how the printer head 25 is interposed between the exposed area 27 of the ink ribbon 29 and the document 31 to be printed on, when the ink cartridge 23 is properly installed into the cartridge holder 33 . In order to print, pins on the printer head 25 are thrust toward the document 31 . Because the ink ribbon 29 is interposed between the printer head 25 and the document 31 , ink from the ink ribbon 29 is transferred to the document 31 as the pins urge the ribbon against the document. As the printer prints, the ink ribbon 29 is advanced across the exposed area 27 by a mechanism (not shown) in the print cartridge 33 . When the ink cartridge 23 is installed into the cartridge holder 33 , contact points on the resistive ink identifier 39 are in electrical communication with contact 35 and 37 disposed on the cartridge holder 33 . The contracts 35 and 37 are in electrical communication with sensor/regulation circuitry 41 . The circuitry 41 is in electrical communication with print head activation circuitry 42 , which regulates movement of the printer head 25 or other functional components of the printer. FIG. 4 a illustrates a basic hardware embodiment of the sensor/regulation circuitry 41 of FIG. 3 . As shown, therein, a sensor 43 is operative to sense the resistive value of the resistive ink identifier. Printer controller 45 is in electrical communication with the sensor 43 and is operative to regulate printing functions, e.g. impact force, in response to the sensed resistive value. The printer controller 45 may comprise a simple comparator circuit (not shown) used to translate the sensed resistive value into printer control data, if necessary. Display 44 is an electrical communication with the printer controller and operative to display information representative of usage data and the amount of ink left in the ink cartridge. FIG. 4 b illustrates a software embodiment utilizing memory 47 in electrical communication with the sensor 43 and printer controller 45 . In this embodiment, the memory is operative to store printer control data correlated to the identified type of cartridge, such as information on the length of the ink ribbon in the ink cartridge, and/or information on the density of ink on that ink ribbon. The memory can also store operational routines for directing printer functions in response to the specific data attributable to the identified cartridge. When the sensor 43 senses the resistive value of the resistive ink identifier, the memory responds to the sensed resistive value by correlating the sensed resistive value with printer control data in memory. The printer control data thus correlated and/or the corresponding operational routines are sent to the printer controller 45 , which regulates printing in response to that input. FIG. 4 illustrates the mechanical method by which printing may be regulated in accordance with a preferred embodiment of the present invention. As striker 49 is operative to cause pins in the printer head to strike the document to be printed on (see FIG. 3 ) The striker may be connected to the pins of the printer head (see FIG. 3 ) in a variety of fashions as known in the art. The striker comprises a coil 51 disposed about a pin or ram 53 . Energizing the coil 51 causes the ram 53 to travel in a direction 55 to a strike point 57 . The strike point 57 is the point at which the pin in the printer head strikes the document to be printed (see FIG. 3 ). Referring now to FIG. 6 , it can be seen how the process of regulating impact force may be accomplished by means of a series of energizations of the coil, or pulses 59 a,b,c . Each pulse 59 a,b,c has a default pulse width 65 a,b,c , which represent the mount of time for which the coil is energized. Points 67 a,b,c which represents the amount of time for which the coil is energized. Points 67 a,b,c which represents the amount of time for which the coil is energized. Points 67 a,b,c represent points in time at which the rain reaches the strike point (see FIG. 50 ). it can be seen from the drawing that the pulse width 65 a,b,c do not extend for the entire time between the points in time 67 a,b,c . In other words, the rain is not normally accelerated during the entire length of its travel to the strike point (see FIG. 5 ) Modification of the impact force of the print head, may therefore be, be accomplished by changing the pulse widths 65 a,b,c , of the pulses 59 a,b,c . For instance, a pulse width addition 69 a,b,c may be added to each pulse width 65 a,c,b . For instance, a pulse width addition 69 a,b,c , may be added to each pulse width 65 a,b,c . Referring again to FIG. 5 , in so doing will result in the ram 53 being accelerated for a greater portion of the time spent traveling in the direction 55 to the strike point 57 . The ram 53 will thereby achieve a higher force by the time it reaches the strike point 57 , and the connected pin of the printer head will therefore strike the document to be printed on with more force (see FIG. 3 ). Accordingly, a relatively higher amount of ink will be transferred from the ink ribbon to the document to be printed on. Correspondingly, reducing the pulse width will reduce the impact force, and lighten the resulting image. As those skilled in the art will recognize, the broader teachings of the present invention may be utilized not only to identify and implement appropriate printer control functions for an identified printer cartridge. The invention also has application where a user may wish to purposely depart from normally nominal printer control functions for a particular purpose. For example, with a mechanical operation of the printer impaired, the user may prefer to implement a higher impact force than would normally be nominal. This can be done by a variety of processes, including removing the resistive label and replacing it with a different label so that results in the application of a higher impact force. As such, the resistive label may serve as a physical variant to control and to implement different control functions in accordance with predefined operational profiles. FIG. 7 illustrates the method of use of the basic circuitry illustrated in FIG. 4 a . First, an ink cartridge is installed into the printer (step 71 ). When the ink cartridge is so installed, the resistive value of its resistive ink identifier is sensed (step 73 ). The printer controller responds to the sensed resistive value by regulating printing (step 75 ). In this embodiment, the resistive value of the resistive ink identifier could be used, for instance, to represent a relative density of the ink on the ink ribbon of the ink cartridge. If the density was relatively high, the printer controller could respond to the sensed resistive value by causing the pins of the print head to strike with less force, i.e. a shorter pulse width. Conversely, if the density was relatively low, the printer controller would respond to the sensed resistive value by causing the pins of the print head to strike with more force. Accordingly, a uniform darkness of printed characters would be achieved by the system no matter what type of print cartridge was installed. FIG. 8 illustrates a basic method of use for the circuitry illustrated in FIG. 4 b . As in the previous method, an ink cartridge is installed (step 71 ) and the resistive value of the resistive ink identifier on the ink cartridge is sensed (step 73 ). However, in this method a memory is used to correlate the sensed resistive value with printer control data in the memory (step 77 ). The correlated printer control data and/or operational routines are input to the printer controller (step 79 ) which then regulates printing in response to the received input (step 75 ). In this embodiment, the resistive value of the resistive ink identifier maybe be used to represent, for instance, a make or model of the print cartridge. The memory would then include information on a variety of characteristics of such make and model, for instance the length of the ribbon or the density of ink on the ribbon, stored as printer control data. The printer controller would respond to this printer control data and/or corresponding operational routines by regulating printing accordingly. The strike force of the pins on the pin head could be increased or decreased, the rate at which the ribbon was cycled through the ink cartridge could be increased, or a number of other functions my be affected. FIG. 9 illustrates a method of implementing the invention in relation to the circuitry illustrated in FIG. 4 b First, the ink cartridge is installed into the printer (step 71 ). If no value is sensed, the printer operates in accordance with default parameters where a resistive value of the resistive ink identifier is sensed (step 73 ), the sensed resistive value is correlated to information set in memory (step 81 ). The information, which may include data and/or operational routines is used to define and implement a pulse width to be employed when energizing the coils of the striker (see FIG. 5 ) In response to this information, the printer controller regulates printing (step 75 ). As printing continues, the value is increased (step 83 ). A counter increments the number of key strokes and that data is used, e.g. combined with the operational routines, to redefine, e.g. increase the pulse width, or to increase impact force. The redefined pulse width and any other redefined parameters maybe stored in memory (step 81 ). The result is that 45 the printer prints more and more, the pulse/width impact force increases accordingly and the striker is thereby caused to strike with a gradually increasing amount of force. As printing is done, the amount of ink available in an ink cartridge is gradually depleted. However, much ink is remaining in the ink cartridge, it is distributed more or less evenly over the ink ribbon. Thus, if less ink is left then the relative density of ink on the ribbon is lower. As a result, in prior art printers, as the ink is depleted the characters printed on a document to be printed grow steadily less dark. Steadily increasing the force with which the striker strikes in accordance with this embodiment of the present invention counteracts with this trend and ensures that the characters printed by the printer continue to be satisfactorily dark. The system may comprise additional elements intended to provide further functionality. For instance, an alarm maybe in electrical communication with the memory. The alarm is operative to generate an alarm when data stored in the memory indicates that a relatively low amount of ink is left in the ink cartridge. Likewise, the system could comprise a display operative to display the amount of ink left in the ink cartridge. Alternatively, the printer controller could be configured to automatically cease functioning when the amount of ink left in the ink cartridge reached a selected threshold level. It is understood that although the above represents several embodiments of the invention, the invention may take a still wider variety of embodiments intended to effect alternate designs or additional features. For instance, the force with which the striker strikes could be modulated by means of varying pulse amplitude instead of pulse width. Such embodiments are within the scope and spirit of the present invention.

A method and apparatus are provided for adaptively controlling printer functions of a dot matrix printer in response to sensing the type of printer ink cartridge being used. An identifying resistive value is applied to surface of the cartridge and installed within the printer. The printer includes contacts that include sensors and sensor circuitry useful to detect a presence of the resistive indicator and the resistive value thereof. The sensed resistive value is used to directly control printer functions, and/or to access stored data or printer control routines specific to the type of cartridge, or desired performance characteristics. Stored information, which may be appended by other sensed information such as printer usage data, is used to selectively regulate printer operation to achieve maximum efficiency and performance from the particular ink cartridge.

This is a division of application Ser. No. 07/472,388, filed Feb. 1, 1990, now U.S. Pat. No. 5,134,073. The present invention relates to an enzyme which has not been previously described and which catalyzes reactions of the following type: ##STR1## Particularly good conversions are obtained with R 1 =(CH 3 ) 2 CH-- and R 2 =H--, as well as with R 1 =CH 3 -- and R 2 =H-- (=2-acetylamino acrylic acid). Nakamichi et al. (Appl. Microbiol. Biotechnol. 19, pp. 100-105, 1984, and Appl. Biochem. Biotechnol. 11, pp. 367-376, 1985) as well as Nishida at al. (Enzyme Microb. Technol. 9, pp. 479-483, 1987) described the occurrence of acylases which hydrolyze 2-acetylamino cinnamic acid (=N-- acetyl-2,3-didehydrophenylalanine) to phenyl pyruvate and acetic acid in bacterial cells of the species Bacillus spaericus and Alcalignes faecalis. Nothing was published about the substrate specificity of these enzymes. Hummel et al. (Appl. Microbiol. Biotechnol. 25, pp. 175-185, 1987) isolated a 2-acetylamino cinnamic acid acylase from a strain of the genus Brevibacterium. However, this enzyme is not capable of splitting other N-acetyl-2,3-didehydroamino acids. The N-acetyl-2,3-didehydroleucine acylase of the invention is characterized by the following qualities: 1) Reactivity: It splits off the acetyl group from N-acetyl-2,3-didehydroleucine, at which time acetic acid and, after consecutive chemical reactions, 2-keto-4-methyl valeric acid and ammonia arise as end products; 2) Substrate specificity: It hydrolyzes both various N-acetyl-2,3-didehydroamino acids such as N-acetyl-2,3-didehydrovaline, N-acetyl-2,3-didehydroisoleucine, 2-acetylamino cinnamic acid and 2-acetylamino acrylic acid as well as amino acid amides such as D- and L-tryptophane amide, D- and L-leucine amide and L-methionine amide but not 2,3-saturated N-acetylamino carboxylic acids such as N-acetyl leucine or N-acetyl valine; 3) Optimum pH: The optimum pH is 9.3±1; 4) pH stability: It exhibits good stability in a pH range between 9 and 10; 5) Optimum temperature: The optimum temperature is 55° C. at a pH of 9; 6) Temperature resistance: At 50° C., 90% residual activity can still be demonstrated after 30 minutes incubation; 7) Influences of inhibitors and activators: Inhibitors of serine proteases, especially phenylmethane sulfonylfluoride (0.001 mM), exert an inhibitory action, glycine accelerates the substrate splitting as a function of the concentration; 8) Molecular weight: The molecular weight is approximately 60,000; 9) Subunits: The molecule consists of only one unit; 10) K M -value: The K M -value for the substrate N-acetyl-2,3-didehydroleucine is 4.5 mM (30° C., 0.1M glycine buffer, pH 9). The N-acetyl-2,3-didehydroleucine acylase of the invention can be recovered by means of a zoogloea strain which was deposited on Dec. 1, 1987 in the German Collection of Microorganisms in Gottingen under number DSM 4306. The following qualities show that the microorganism belongs to the species Zoogloea ramiger: It grows in slightly curved, Gram-negative rods. The cells can be moved by a polar flagellum and do not form spores. Growth occurs without nitrate strictly aerobically. No acid is formed from glucose. Catalase and oxidase reaction as well as nitrate reduction are positive, urea splitting positive, gelatin and casein decomposition positive, starch breakdown negative, denitrification negative (unusual for the genus Zoogloea). The strain contains the ubiquinone Q 9. The microorganism can be preserved as lyophilized culture. Working cultures are maintained on oblique agar tubes (N-acetyl-2,3-didehydroleucine medium). In order to recover the N-acetyl-2,3-didehydroleucine acylase of the invention, Zoogloea ramigera DSM 4306 is cultivated in an aqueous nutrient medium containing a source for carbon and nitrogen and mineral salts at an initial pH between 7.5 and 9 aerobically at 25° to 38° C., then N-acetyl-2,3-didehydroleucine is added to the nutrient solution as inductor and the mixture is cultivated further aerobically at pH 6.5 and at 28° to 38° C., the cell mass separated and the enzyme isolated from the cells. The enzyme can be recovered in larger amounts e.g. by cultivating Zoogloea ramigera in a known manner in a bioreactor of the desired size, e.g. with a working volume of 5 liters. The following is important for a successful culture: A good aerating (obligatorily aerobic organism); The presence of nutrients, e.g. in complex form as yeast extract; A gradual subsequent introduction of the nutrients; For growth, a pH between 7.5 and 9; For the enzyme production, a pH of 6.5; For the enzyme production, the presence of N-acetyl-2,3-didehydroleucine (5 to 9 g/l). The enzyme can be recovered after digestion of the cells by a combination of known methods of enzyme purification. The enzyme can be used as a component of a coupled enzyme system with an L-leucine dehydrogenase for the enzymatic conversion of N-acetyl-2,3-didehydroleucine via the intermediary stage 2-imino-4-methyl-valeric acid or the corresponding keto acid to L-leucine. In addition, the enzyme can be used for the preparation of D- or L-tryptophyl glycine from D- or L-tryptophane amide and glycine, of D- or L-tryptophyl-D-methionine from D- or L-tryptophane amide and D-methionine as well as of L-tryptophyl-D-cysteine from L-tryptophane amide and D-cysteine. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The invention is explained in more detail in the following examples. The following abbreviated formulas are used: N-acetyldehydro- for N-acetyl-2,3-didehydro-, ADL for N-acetyl-2,3-didehydroleucine, ADI for N-acetyl-2,3-didehydroisoleucine and ADV for N-acetyl-2,3-didehydrovaline. EXAMPLE 1 Search for N-acetyldehydroleucine acylase producers 63 soil, water and sewage plant specimens were suspended and diluted with a mineral salt solution and 20 ml liquid medium (enrichment medium) were inoculated with 0.02-0.2 ml of these batches. The mineral salt solution exhibited the following composition: ______________________________________K.sub.2 HPO.sub.4 3.7 gKH.sub.2 PO.sub.4 1.5 gMgSO4.7H.sub.2 O 0.2 gCaCl.sub.2.2H.sub.2 O 2.0 mgZnSO.sub.4.7H.sub.2 O 0.4 mgFeCl.sub.3.6H.sub.2 O 0.2 mgDeionized water 1.0 lpH 7.2______________________________________ The enrichment medium contained: ______________________________________N-acetyldehydroamino acid 3.0 gTrace-element solution 3.0 mlYeast extract 0.2 gMineral salt solution (see above) 1.0 lpH 7.2______________________________________ The leucine, isoleucine and valine derivatives were used as N-acetyldehydroamino acids. Prior to the inoculation, the medium was introduyced into 100 ml Erlenmeyer flasks and sterilized by autoclaving. After cooling, 0.02 ml vitamin solution, sterilized by filtration, was added to each flask (composition of the vitamin solution according to H. G. Schlegel, "Allgemeine Mikrobiologie", Thieme Verlag, 1981, p. 169). The cultures were incubated aerobically at 28° C. in a rotary agitator at 110 rpms for 6-10 days. Densely overgrown batches with an optical density at 660 nm of at least 0.7 were diluted in sterile phosphate buffer (20 mM, pH 7) in a conventional manner and plated out onto selective nutrient media with the following composition: ______________________________________Agar 2.0 gYeast extract 0.1 gEnrichment medium (see above) of the 1.0 lparticular culturepH 7.2______________________________________ The medium was autoclaved without vitamin solution and the latter not added until after the cooling of the agar before pouring out into steril Petri dishes in the amount indicated above. Reference plates of each enrichment culture were also inoculated in parallel as described, which plates exhibited the same composition as the selective nutrient media but contained no N-acetyldehydroamino acids. The inoculated plates were incubated 3 to 10 days at 28° C. A colony was removed from each of the colony types which could be found only on the selective nutrient media but not on the reference plates and was placed in a conventional manner on the selective agar in pure culture (dilution smears, microscopy). Strains which appeared homogenous were then multiplied in 100 ml liquid medium (500 ml Erlenmeyer flask) at 27° C. on a rotary agitator machine at 110 rpms. The culture medium had the following composition: ______________________________________Yeast extract 0.5 gPeptone 0.5 gEnrichment medium (see above) of the 1.0 lorganism to be testedpH 7.2______________________________________ After 48-60 hours, the contents of the agitator flask were centrifuged (20 min., 8,000 g in a refrigerated centrifuge) and the sedimented cells were suspended in 0.05M potassium phosphate buffer, pH 7 (4 ml buffer per 1 g moist bacterial mass). The microorganisms in this suspension must be digested in a customary manner (e.g. agitation with fine glass beads, ultrasound treatment, French press). For this purpose, the suspensions were compounded with glass beads (0.1 to 0.2 mm diameter) using 2 g glass beads per 1 ml cellular suspension and then mixing the mixture in a test tube for 10 minutes with a laboratory agitator (type Reax 2000, Heidolph company). Most of the organisms were able to be well digested with this method. Indissoluble cellular components and the glass beads were centrifuged off (13,000 rpms, Biofuge A, Heraeus company) and the supernatant used as enzyme source (raw extract). The batches for the activity test contained: ______________________________________0.2 M N-acetyldehydroamino acid 0.05 mlraw extract 0.075 ml0.05 M tris/HCl buffer, pH 7.2 0.375 ml.______________________________________ All raw extracts were tested at least with N-acetyldehydroleucine and N-acetyldehydroisoleucine but, in most cases, also with N-acetyldehydrovaline. Incubation time and raw-extract dilution were measured in such a manner that the linearity range of the following color test for the demonstration of the reaction product (0.26 mM keto acid) was not exceeded. The enzymatic reaction was stopped in the batches incubated at 30° C. by adding 0.25 ml color reagent (1 g/l 2,4-dinitrophenyl hydrazine in 2N HCl). After further incubation at 30° C. for 10 minutes with N-acetyldehydroleucine as substrate or 25 minutes with the isoleucine or valine derivative, 1.5 ml 2,5N NaOH was added The keto acid released by the enzymatic hydrolysis forms, together with the 2,4-dinitrophenyl hydrazine, a Schiff's base colored red in the alkaline whose absorption was measured in a spectral photometer at 442 nm against a batch without N-acetyldehydroamino acid (=enzyme blank). A blank reading was deducted from these extinction values which blank reading is obtained if the extinction value of a batch only with buffer (=buffer blank) is deducted from that of a batch with buffer and N-acetyldehydroamino acid but without raw extract (=substrate blank). The concentration of the product produced was determined with a calibrated reference for the corresponding keto acid. The enzyme activity is indicated in international units. One unit (U) corresponds to an amount of 1 μmole released keto acid per minute. As table 1 shows, the strain Zoogloea ramigera ABI 1 (DSM 4306) exhibits the highest activity in the above-described test procedure and was therefore used for the production of the enzyme. TABLE 1______________________________________Production of N-acetyldehydroamino acid acylase bymeans of the 7 most active microorganisms in the screeningSubstrate:ADL ADI ADV Specific Vol. Specific Vol. Specific Vol. Activity Yield Activity Yield Activity YieldStrain (mU/mg) (U/l) (mU/mg) (U/l) (mU/mg) (U/l)______________________________________ABI I 147 11.5 19 1.41 48 3.72ABI 3 103 11.0 15 1.62 28 2.98ABI 5 100 9.1 8 1.21 29 2.64SZI 2 77 4.1 13 0.70 27 1.47SZI 4 109 7.1 12 0.81 33 2.14SZI 5 69 4.2 15 0.90 35 2.12SZI 7 129 10.9 15 1.49 30 2.94______________________________________ EXAMPLE 2 Production of N-acetyldehydroleucine acylase a) Acylase fermentation with strain ABI 1 on a 5 l scale A bioreactor with 5 liter working volume was used which was equipped with a device for the automatic regulation of the pH and foam inhibition. The medium contained: ______________________________________Yeast extract 35.0 gMineral salt solution (cf. example 1) 5.0 lpH 8.3______________________________________ After sterilization, the medium was inoculated with 500 ml of a preculture which had been cultivated for 60 hours in portions of 150 ml of the same medium in 500 ml Erlenmeyer flasks. The incubation took place at 30° C. and 100 rpms on a rotary agitator. The conditions during the growth phase of the fermentation were: ______________________________________pH 8.3Temperature: 35.0° C.Concentration of dissolved oxygen 80%(% saturation)Maximum agitator speed 300 rpms______________________________________ Specimens were taken at different times and the cell growth followed by means of turbidimetric measurement (measurement of the optical density) at 660 nm. 300 ml of a concentrated yeast extract solution sterilized by autoclaving (100 g/l in mineral salt solution as described in Example 1) were added after 10, 21 and after 24 hours each to the fermenter contents under aseptic conditions. After approximately 25 to 30 hours incubation, when no further increase of the bacterial mass could be detected, 3.5 liters of the medium were filtered off by means of a sterilely coupled cross-current microfiltration system (type Sartocon II, 0.6 m 2 polyolefin membrane, pore diameter 0.2 μm, company Sartorius). The fermenter contents were passed through the filtration module by means of a hose pump at 185 liters per hour so that a pressure difference of 0.8-0.9 bar was produced between the module inlet and the module outlet. The bacterial cells and the non-separated liquid medium were returned into the fermenter. The hose connections between the fermenter and the filtration unit, including the pump hose, had previously been sterilized by autoclaving and the filtration system had previously been sterilized by means of water vapor flowing through it (1.2 bars superpressure, 30 minutes). The concentrated biomass in the reactor was washed by diafiltration with 2 liters of sterile mineral salt solution (cf. example 1) and then the fermenter was filled with induction medium. The induction medium was composed as follows: ______________________________________N-acetyldehydroleucine 25 g/lYeast extract 35 g/lMineral salt solution 4.5 lpH 6.5______________________________________ The conditions for enzyme induction were: ______________________________________pH 6.5Temperature 31.5° C.Concentration of the dissolved 80%oxygen (% saturation)Maximum agitator speed 300 rpms______________________________________ Specimens were taken at different times and the maximum attainable enzyme content and the best harvesting time determined after turbidimetric measurement (optical density at 660 nM) and a test for acylase activity. The acylase tests were prepared with 0.02M N-acetyldehydroleucine in 0.1M glycine/sodium hydroxide buffer, pH 10, and carried out as described in Example 1. It was found that the acylase is formed only during the 2nd fermentation phase and the enzyme activity reaches its maximum value approximately 24 hours after the addition of the induction medium. b) Recovery of the raw extract The moist bacterial mass (133 g) was suspended in 50 mM glycine buffer, pH 11, so that the concentration of the cellular suspension was 40% (final volume 333 ml). The cell contents were released in the cooled suspension (approximately 4° C.) by means of a mechanical cellular digestion in a glass bead mill (Bachofen-Dyno-Mill, type KLD). The grinding container, comprising 680 ml, was filled with glass beads 0.3 mm in size, so that a bulk volume of 578 ml resulted (85%). The digestion was carried out at an agitator-shaft speed of 3000 rpms while the cooling jacket of the grinding container as well as the agitator shaft bearing were cooled during running with ethylene glycol solution of -20° C. in order to largely avoid a heating of the product. After 4 minutes digestion time, a degree of disintegration of over 90% was achieved. The glass beads were separated by means of 2 minutes centrifugation at 3000 g, washed twice by mixing them each time with 192 ml glycine buffer and were centrifuged off again. The supernatants of the centrifugation steps were combined and the greater part of the cell fragments separated by means of 30 minutes centrifugation at 12000 g in a refrigerated centrifuge. It was found that the raw extract, compounded to 50% (w/v) with glycerin, could be stored at -20° C. for months without loss of activity. EXAMPLE 3 Growth of Zoogloea ramigera ABI 1 a) Growth at various start pH'es The pH was varied from 6.5-10 in stages of 0.5 units in a medium consisting of mineral salt solution (cf. Example 1) and 7 g/l yeast extract. Specimens were taken at different times from the cultures (30 ml in 100 ml Erlenmeyer flasks) incubated on a rotary agitator machine at 110 rpms at 30° C. in which specimens the bacterial mass was determined by measuring the optical density at 660 nm. After 43 hours of growth, the highest cell density was reached in a pH range between 8 and 8.5 b) Growth at different yeast extract concentrations The growth of strain ABI 1 was followed in agitated cultures (as described under a)) with a medium of mineral salt solution (cf. Example 1) and 7-25 g/l yeast extract with an initial pH of 8.25 by measuring the optical density at 660 nm. It was found that the rate of microorganism growth is retarded when the yeast extract concentration is 15 g/l or more. EXAMPLE 4 Induction of N-acetyldehydroleucine acylase a) Changing of the inductor Different substances were added in a concentration of 3 g/l as inductors into agitated cultures with a medium of mineral salt solution (cf. Example 1) with 0.5 g/l yeast extract and 0.5 g/l peptone at pH 7. The technology for agitated cultures is described in Example 1 a). As can be seen from Table 2, N-acetyldehydroleucine exhibits the highest induction capacity. N-acetylamino acids or 2-acetylamino cinnamic acid are only slightly active. TABLE 2______________________________________Acylase activity after 60 hours of incubation as afunction of the inductorInductor U/mg Inductor U/mg______________________________________AD-leucine 0.222 Ac-L-leucine 0.018AD-isoleucine 0.172 Ac-D,L-tryptophan 0.018AD-valine 0.121 2-Acetylamino- 0.016Ac-L-isoleucine 0.039 cinnamic acidAc-D,L-valine 0.031 Ac-D,L-tyrosine 0.011Ac-D,L-phenylalanine 0.031 Control 0.015AD: N-acetyldehydro- AC: N-acetyl-______________________________________ b) Variation of the starting pH The pH was varied from 5.5-9 in stages of 0.5 units in the mineral salt medium with 3 g/l N-acetyldehydroleucine and 2 g/l yeast extract. The enzyme production reaches its optimum at pH 6.5 and drops sharply as the pH increases, as is shown in TABLE 3______________________________________Relationship between the acylase formation bymeans of strain ABI 1 and the pHpH U/mg U/l______________________________________5.5 * *6.0 * *6.5 0.202 14.67.0 0.136 13.37.5 0.115 10.88.0 0.075 7.68.5 0.069 5.39.0 0.064 5.3______________________________________ *not determined, since growth too slight c) Varying the concentration of N-acetyldehydroleucine Zoogloea ABI 1 was cultivated in a mineral salt medium with start pH 8 and 7 g/l yeast extract at 30° C. with a rotary agitator machine. After 48 hours, the cells were centrifuged for 10 minutes at 8000 g, resuspended in the above-mentioned medium with different concentrations of N-acetyldehydroleucine and a pH of 6.5 and incubated for a further 16 hours in a rotary agitator. Table 4 shows that no further increase of the enzyme production can be detected above 5 g/l N-acetyldehydroleucine. TABLE 4______________________________________Acylase activity as a function of the N-acetyldehydroleucineconcentration in a two-stage agitated cultureN-acetyldehydroleucine Acylase production(g/l) U/mg U/l______________________________________control 0.015 53 0.140 415 0.189 707 0.190 659 0.204 72______________________________________ EXAMPLE 5 Purication of the Acylase a) Precipitation of nucleic acids with polyethylene imine A raw extract (666 ml) was obtained by means of fermentation, cellular digestion in a glass bead mill and centrifugation. The extract was cooled in an ice bath and combined with 35 ml of a 10% polyethylene imine solution (rel. molecular mass 30-40·10 3 ) with a pH of 11 and incubated 5 minutes at 0° C. The precipitated nucleic acids, as well as cell fragments not yet separated out, were sedimented by means of 30 minutes centrifugation in a refrigerated centrifuge at 18000 g. It was possible to increase the yield by 18.6% and the enrichment factor by 206% by means of the nucleic acid precipitation in the subsequent ammonium sulfate fractionation. b) Protein precipitation with ammonium sulfate The supernatant (690 ml) was compounded with 460 ml of a saturated ammonium sulfate solution (761 g/l) whose pH had been adjusted by the addition of solid sodium hydroxide to 9 and was agitated 30 minutes in an ice bath. The precipitated protein was sedimentated 30 minutes at 15000 g in a refrigerated centrifuge and dissolved in 200 ml 50 mM glycine buffer with a pH of 11. c) Salting-out chromatography on sepharose CL-4B The concentrated dissolved protein precipitate was treated by adding ammonium sulfate solution until a conductivity of 80-90 mS/cm had been achieved, which corresponds at pH 11 to an ammonium sulfate concentration of approximately 25% saturation. Precipitated protein was centrifuged off at 15000 g (30 minutes). 125 ml of the supernatant (250 ml in toto) were applied onto a sepharose CL-4B column (2.6×22.6) which had been equilibrated with 25% ammonium sulfate (pH 11). The elution took place by establishing a gradient (500 ml) decreasing from 26 to 0%. The eluate was trapped in fractions of 5 ml. The acylase desorbed at 17-19% ammonium sulfate saturation from the chromatography gel. The active fractions (25 ml) were combined and diluted with saturated ammonium sulfate solution (pH 9) to the double volume. After 30 minutes incubation in an ice bath, the precipitated protein was centrifuged off and taken up in 2 ml 50 mM glycine buffer with pH 11. The concentrated acylase preparation was compounded to 43.5% (w/v) with glycerin and stored at -20° C. Since only 10-17% of the applied protein bonds to the column in the chromatographic process described here, it is possible to work up large amounts of protein with a relatively small column. d) Analytical fast protein liquid chromatography (FPLC) on Mono-Q 0.255 ml of the concentrated acylase preparation compounded with glycerin was diluted with 1.13% (v/v) Triton X-100 in 50 mM glycine buffer (pH 11) to 2 ml and applied onto the Mono-Q column (1 ml), which had been equilibrated with the above-mentioned glycine buffer supplemented with 0.2% Triton X-100. Elution was carried out with a Na 2 SO 4 gradient (40 ml) rising from 0 to 0.15M while the acylase was washed at 0.047-0.050M Na 2 SO 4 from the column. After the active fractions had been combined, the purified enzyme was partially compounded with 43.5% (w/v) glycerin for storage at -20° C. and partially glycerinated to 25% (w/v) for preservation at 4°-8° C. in a refrigerator. No activity loss could be recorded under the latter conditions after 76 days. Table 5 shows the results of the purification. TABLE 5______________________________________Purification scheme for N-acetyldehydroleucine acylaseSpecimen/ Total Specific Enrich-purification Enzyme Yield Activity mentstep (U) (%) (U/mg) Factor______________________________________Raw extract 1963 100 0.348 1Nucleic acid 1810 92 0.376 1.08precipitation (0.9% PEI)Ammonium sulfate 1505 77 1.27 3.65precipitation (0-40%)Salting-out chromatogr. 785 40 12.0 34.5(26-0% ammoniumsulfate)Concentrating 785 40 13.3 38.2(precipitation with 60%ammonium sulfate)FPLC-Mono-Q (0-0.15M 557 28 74-109 213-313sodium sulfate in 0.2%Triton X-100)______________________________________ PEI: Polyethylene imine, rel. molecular mass: 30-40 · 10.sup.3 EXAMPLE 6 Effect of pH on the Reaction Rate The reaction rate of the hydrolytic splitting of acetic acid from the compound N-acetyldehydroleucine in the presence of the ADL acylase was determined as a function of the pH in the reaction mixture. The test batch was composed as follows: ______________________________________200 mM N-acetyldehydroleucine in 20 mM tris/ 0.05 mlphosphoric acid buffer (pH 9)1.0 U/ml acylase 0.01 ml0.1M buffer 0.44 ml______________________________________ Before the reaction batches were mixed together, different pH values in the range of 5 to 7.5 in the potassium phosphate buffer, 7.5 to 9 in the tris buffer and 7 to 12 in the glycine buffer were adjusted by means of the addition of sodium hydroxide and phosphoric acid. The pH values present under test conditions were measured in reference batches without enzyme. After 10 minutes reaction time at 30° C., the enzyme activities were determined by means of colorimetric measuring of the keto acid concentration (cf. Example 1). The optimum for the reaction rate in the glycine buffer is in a pH range between 8.6 and 10.1, in the glycine-free buffers between 7.7 and 9.1. EXAMPLE 7 Optimum Reaction Temperature Test batches with 20 mM N-acetyldehydroleucine in 0.1M glycine buffer (pH 9) were pretempered 5 minutes at temperatures between 10° and 70° C. and then the enzyme reaction was started by means of the addition of acylase. At temperatures of 10° to 40° C., the batches contained 0.0666 U/ml enzyme, at 40° to 70° C. 0.02 U/ml. After 2 minutes, the enzyme reactions were stopped by means of the addition of ice-cooled analytical reagent, the test tubes cooled down in an ice bath and, after 15 minutes incubation at 30° C., alkalized as is customary for color development (cf. Example 1). The maximum reaction rate is reached at 55° C. and is greater by a factor of 3.1 than at the standard temperature of 30° C. EXAMPLE 8 Stability of the N-acetyldehydroleucine acylase a) pH stability The pH stability of the ADL acylase was investigated in the pH range of 7 to 12. Enzyme purified on Mono-Q was diluted 20-fold with various buffers of differing pH values and stored for 3 weeks at 25° C. Specimens were taken at various times and their enzyme activities were tested under standard conditions. The following buffers were used for the different values: ______________________________________0.1M potassium phosphate pH 7.01, 7.50.1M tris/phosphoric acid pH 7.5, 8.0, 8.5, 9.00.1M glycine pH 9.0, 9.5, 10.0, 10.5, 11.0, 11.5, 12.0______________________________________ The mixing together of the batches, their storage and the taking of specimens took place under sterile conditions. The standard conditions for the enzyme test were: 20 mM N-Acetyldehydroleucine Acylase in a limiting amount so that the linearity range of the subsequent color test (cf. Example 1) was not exceeded 0.1M glycine buffer pH 9 As is apparent in Table 6, approximately 30-40% of the original acylase activity was still detectable in the pH range of 9-10.5 after 3 weeks. TABLE 6______________________________________pH Stability of the A-acetyldehydroleucine acylaseBuffer Residual activity (%) afterpH 1 day 3 days 1 week 2 weeks 3 weeks______________________________________Potassiumphosphate(0.1M)7.0 78 16 0 0 07.5 83 39 0 0 0Tris/phos-phoric acid(0.1M)7.5 61 37 0 0 08.0 60 44 7 0 08.5 63 62 37 13 99.0 92 80 56 25 27Glycine(0.1M)9.0 97 91 64 35 309.5 89 103 68 35 3710.0 102 99 68 34 4310.5 98 95 57 28 2511.0 86 86 54 15 711.5 71 69 35 5 212.0 4 3 0 0 0______________________________________ b) Temperature resistance of the acylase The acylase was incubated 30 minutes at temperatures of 10° to 70° C. and then the activity test was carried out under standard conditions (cf. Example 8a)). After 30 minutes at 50° C., 89% of the initial activity can still be demonstrated, at higher temperatures the acylase is rapidly deactivated. c) Stability of the acylase in the presence of different anions The influence of different anions on the stability of ADL acylase was investigated. Raw extract which had been compounded with glycerin to 43.5% (w/v) was diluted 1:10 with 0.5 molar solutions of various sodium salts in 50 mM glycine (pH 11) and stored at room temperature (20° to 25° C.). Specimens were taken from time-to-time and their enzymatic activity measured under standard conditions, as described in Example 8a). It was found that the stability of the acylase increases with the charge and the size of the anion (cf. Table 7). TABLE 7______________________________________Stability of N-acetyldehydroleucine acylase in thepresence of various sodium saltsSodium salt % Residual activity after(0.5M) 3 days 6 days 21 days______________________________________Phosphate 96 105 27Sulfate 89 94 15Acetate 86 81 6Formate 76 63 2Chloride 35 0 0______________________________________ EXAMPLE 11 Influences of Inhibitors and Activators a) Influence of chelating agents, metal cations and enzyme inhibitors The influence of various additive substances on the reaction rate of the splitting of N-acetyldehydroleucine was measured under standard conditions, as described in Example 8a). It can be seen from Table 8 that only inhibitors of serine hydrolases sharply inhibit the acylase, especially phenylmethane sulfonyl fluoride still in micromolar concentration. TABLE 8______________________________________Influence of additive substances on theN-acetyldehydroleucine acylase activity % Residual activityInhibitor 1 mM 10 mM 100 mM______________________________________Complexing agents:EDTA * 95 *Citrate 99 84 *Bipyridine 91 70 *Phenanthroline 94 52 *NaN.sub.3 105 103 *Bivalent Cations:CaCl.sub.2 * 93 *CuSO.sub.4 87 83 *CoCl.sub.2 91 85 *MgCl.sub.2 95 88 *MnCl.sub.2 99 87 *ZnCl.sub.2 95 82 *Reducing agents:MeSH 93 99 81Glutathione reduced 95 95 *Dithiothreitol 103 58 *SH Group reagents:pCMB 104 98 *pOHMB 93 91 *iodine acetamide 104 74 *iodine acetate 76 49 *HgCl.sub.2 84 70 *KCN 105 * *Inhibitors of PLP enzymes:Cycloserine 111 105 *Semicarbazide 113 93 *Inhibitors of serine hydrolasesNeostigmine 102 82 0pABA**) * 89 54PMSF 0.0001 mM: 0.01 mM: 10 0 *______________________________________ *defined above as "not determined, as growth too **pABA to 200 mM: 0% residual activity MeSH: mercaptoethanol pABA: paraaminobenzamidine pCMB: parahydroxy mercury benzoate PLP: pyridoxal phosphate pOHMB: parahydroxy mercuric benzoate PLP: Pyridoxyl phosphate PMSF: phenylmethane sulfonyl fluoride b) Influence of glycine on the reaction rate The reaction of glycine in 0 to 1.2 molar concentration dissolved in 0.1M tris/HCl buffer was determined under standard conditions (example 8a). Glycine accelerates the splitting of N-acetyldehydroleucine by the ADL acylase a maximum of 3.3 times. The glycine concentration which is necessary for one-half the maximum reaction acceleration is 90 mM (calculation according to T. Ingami and T. Murachi, J. Biol. Chem. 238 (5), pp. 1905-1907, 1963). EXAMPLE 12 Determination of the Molecular Weight and of the Number of Subunits The molecular weight of the native enzyme was determined by means of gel filtration on sephacryl S-200 HR. The column (1.6×69.6 cm), coupled to a FPLC system, was operated with a flowthrough rate of 1 ml/minute and 0.1 ml of the enzyme which was glycerinated and purified by means of salting-out chromatography served as specimen after a twofold dilution. The following served as reference proteins: Cytochrom C (horse), myoglobin (whale), myoglobin (horse), aldolase (rabbit muscle), carboanhydrase and bovine serum albumin. The molecular weight of the acylase is 65,000±5000. A molecular weight of 55,000±4000 was determined in gel electrophoresis in the presence of sodium dodecylsulfate (SDS) for the denatured enzyme. Accordingly, the acylase consists of a polypeptide chain of an unusual length. The following were used for the calibration curve: α 2 -macroglobulin (equine plasma), phosphorylase b (rabbit muscle), glutamate dehydrogenase (bovine liver), lactate dehydrogenase (swine muscle) and trypsin inhibitor (soy bean). EXAMPLE 13 Substrate specificity of N-acetyldehydroleucine acylase a) Dependency of the acylase activity on the concentration of various N-acetyldehydroamino acids The activity of the acylase was determined under standard conditions (cf. Example 8a)) with various N-acetyldehydroamino acids in concentrations of 0.1 to 300 mM. A second series of measurements with N-acetyldehydroleucine in the above-indicated concentration range was placed in 0.1M tris/phosphoric acid buffer. The K M value for ADL is 4.5 mM in glycine buffer. The kinetic data for the splitting of the acetyldehydroamino acids is collated in Table 9. TABLE 9______________________________________Kinetic data of N-acetyldehydroleucine acylase K.sub.M K.sub.ISubstrate Buffer % V.sub.max (mM) (mM)______________________________________ADL glycine, 0.1M 100 4.53 418ADI glycine, 0.1M 14 5.77 140ADV glycine, 0.1M 23 20.9 732ACA glycine, 0.1M 46 2.62 942ADA glycine, 0.1M 90 6.68 714ADL tris-phosphoric acid 0.1M 62 7.01 2564______________________________________ Reaction conditions: 0.1M glycine, pH 9, 30° C. Adaptation to the equation v = V.sub.max. · S/(K.sub.M + S + S.sup.2 /K.sub.I) (W. Cleland, 1963, Methods in Enzymology 63, pp. 103-138). ADL: acetyldehydroleucine ADI: acetyldehydroisoleucine ADV: acetyldehydrovaline ACA: acetylamino cinnamic acid ADA: acetyldehydroalanine (═Nacetylamino acrylic acid). b) Hydrolysis of other compounds by N-acetyldehydroleucine acylase A qualitative check was performed for 81 compounds to see whether they are accepted as substrate by the acylase. The test batches contained: 50 mM test substrate 0.343 U/ml acylase 0.1M tris/HCl buffer pH 9 After 16 and 40 hours incubation at 25° C., specimens were taken from the batches, most of which specimens were analyzed in comparison to substrate standards by means of thin-layer chromatography (70% (v/v) ethanol as mobile solvent). The detection took place with ninhydrin spray reagent. A few specimens were tested in addition or alternatively with the amino acid analyzer. The test batches for the hydrolysis of hydantoins had the following composition: 25 mM substrate or buffer 1 U/ml acylase 50 mM tris/phosphoric acid buffer pH 9 total volume 100 μl Isopropylhydantoin, hydantoic acid and dihydrouracil were used as substrates. After 11.5 hours at 30° C., 175 μl 12% (w/v) trichloroacetic acid and 25 μl analytical reagent (10% (w/v) p-aminobenzaldehyde in 6N HCl) were added, precipitated protein centrifuged off in an Eppendorf table centrifuge and the absorption in the supernatants measured at 450 nm. In order to determine the enzymatic hydrolysis rate of 4-nitrophenylacetate, the rate of increase in extinction of the liberated 4-nitrophenol (402 nm) was measured for the following batch: 20 mM 4-nitrophenylacetate 0.2 U/ml acylase 0.1M potassium phosphate buffer pH 7 25° C. In order to take the chemical hydrolysis into account, the extinction increase rate in a batch without acylase was deducted from the value determined in this manner. The enzyme activity was calculated using a straight calibration line with 4-nitrophenylacetate. The amino acids produced from the amino acid amides by means of the action of acylase were detected quantitatively with the amino acid analyzer. For the determination of the relative activities, the hydrolysis rate with N-acetyldehydroleucine under comparable reaction conditions was equated with 100%. Only tryptophane amide is split with a reaction rate on the order like that achieved with N-acetyldehydroamino acids (cf. Table 10). TABLE 10______________________________________Substrate specificity of N-acetyldehydroleucine acylaseSubstrate rel. activity (%)______________________________________ADL 100.0L-tryptophane amide 20.4L-leucine amide 6.80D-leucine amide 3.82L-methionine amide 4.69L-alanine amide 0.35D-alanine amide 0.464-nitrophenylacetate 1.1N-acetyl glycine 0L-tryptophyl glycine 0L-leucyl glycine 0L-alanyl glycine 0Glycyl-L-leucine 0L-alanyl-L-leucine 0N-acetyl-L-alanyl-L-valine 0L-alanyl-L-phenylalanine amide 0N-acetyl-D,L-leucine 0N-acetyl-L-phenylalanine 0N-benzoyl-D,L-leucine 0N-methoxycarbonyl-D,L-leucine 0N-methoxycarbonyl-D,L-valine 0N-methyl-D,L-leucine 0N-methyl-L-glutamic acid 0N-carbamoyl-L-valine 0N-carbamoyl-L-phenylalanine 0Isopropylhydantoin 0Dihydrouracil 0______________________________________ EXAMPLE 14 Continuous Preparation of L-leucine N-acetyldehydroleucine can be converted enzymatically to L-leucine by reductively aminating the intermediate 2-keto isocaproate stereospecifically by means of coupling the acylase with an L-leucine dehydrogenase. The regeneration of the coenzyme oxidized in the dehydrogenation reaction took place in the presence of formate by means of a formate dehydrogenase. The reaction was carried out continuously in an enzyme membrane reactor. The latter contained, at the start of the experiment: 6.63 U/ml Acylase (prepared with 75 U/ml from the salting-out chromatography) 11.2 U/ml L-leucine dehydrogenase (Bacillus cereus) 8.4 U/ml formate dehydrogenase (Candida boidinii) 0.6 mM PEG 20000-NADH (prepared according to German Patent DE-PS 2,818,414) 900 mM ammonium formate (pH 9). The reactor contents (10 ml), tempered to 25° C., were pumped by a hose pump in a circuit via an ultrafiltration membrane (type YM5, company Amicon, exclusion limit 5000 Daltons). The low-molecular substances can be continuously removed by this means, whereas the enzymes and the coenzyme, which is increased in molecular weight, are retained in the reaction solution. The volume of the ultrafiltered product solution, approximately 9 ml/hour, was continuously replaced with substrate solution. The average dwell time was accordingly 1.1 hours. The substrate solution contained 50 mM N-acetyldehydroleucine in the first 53 operating hours and 75 mM in the following 57 hours, dissolved in each instance in 900 mM ammonium formate with pH 9. The product solution was collected in fractions and its L-leucine concentration determined by means of an enzymatic test with L-leucine dehydrogenase according to the end-point method. The test batches contained: 10% (v/v) specimen or standard with a maximum of 2 mM L-leucine 3.4 mM NAD + 4.8 U/ml L-leucine dehydrogenase 80 mM glycine buffer, pH 10.7 The extinction (340 nm) was measured in the batches prior to the start of the reaction, by means of the addition of enzyme, as well as after 90 minutes incubation at room temperature, and an L-leucine concentration determined from the difference using a calibration curve. Table 11 shows that it is possible to convert N-acetyldehydroleucine to L-leucine in a continuous manner with a high yield. TABLE 11______________________________________Continuous preparation of L-leucine from N-acetyldehydroleucine N-acetyldehydro- Yield of Conver-Time interval (h) leucine (mM) L-leucine*.sup.) (%) sion (%)______________________________________0-53 50 90 9153-110 75 84 86______________________________________ *.sup.) average values in time EXAMPLE 15 Preparation of L-tryptophyl glycine from L-tryptophane amide and glycine a) pH optimum of the L-tryptophyl glycine syntheses It is possible to prepare L-tryptophyl glycine (O-Trp-Gly) from L-tryptophane amide (L-Trp-NH 2 ) and glycine by the action of ADL acylase. L-tryptophane (L-Trp) and ammonia are produced as byproducts. Different pH values between 7 and 11 were adjusted in batches consisting of 50 mM L-Trp-NH 2 200 mM glycine 2.6 U/ml ADL acylase 100 mM buffer at pH 7-9 by means of the addition of sodium hydroxide solution and phosphoric acid. Potassium phosphate was used as buffer substance at pH 7 and tris/phosphoric acia at pH 8 and 9. After 18 hours incubation at 25° C., the composition of the specimens was investigated in comparison to standard solutions by means of thin-layer chromatography. The mobile solvents used were glacial acetic acid/butanol/water in a volumetric ration of 2/8/2 as well as methylethylketone/pyridine/water/glacial acetic acid in a ratio of 70/15/15/2. The detection took place in the case of the first-named mobile solvent via UV quenching of fluorescence at 254 nm as well as with the ninhydrin spray reagent and in the case of the latter mobile solvent only with the ninhydrin method. The concentrations of L-Trp and L-Trp-Gly were determined using standards on an amino acid analyzer. As can be seen from Table 12, the optimum of the synthesis reaction is at pH 10. At this pH, 94% of the L-Trp-NH 2 added is split and 64% thereof converted to the dipeptide (64% selectivity). TABLE 12______________________________________Influence of the pH on the synthesis of L-tryptophyl glycine Dipeptide yield Selectivity ConversionpH (%) (%) (%)______________________________________7 10 10 1008 25 25 1009 44 45 989.5 53 57 9210 60 64 9410.5 53 63 8411 45 62 73______________________________________ b) Influence of the L-Trp-NH 2 concentration on the L-Trp-Gly syntheses The L-Trp-NH 2 concentration of 24.4 to 400 mM was varied in batches for the synthesis of L-Trp-Gly from L-Trp-NH 2 and glycine in the presence of ADL acylase (purified via salting-out chromatography). Glycine was added in a 400-488 molar excess to the L-Trp-NH 2 and the acylase concentration raised in proportion to that of the L-Trp-NH 2 (3.6 U/ml per 50 mM L-Trp-NH 2 ). Incubation and evaluation took place as described in a). In the range from 24 to 182 mM, over 50% of the L-Trp-NH 2 is converted to the dipeptide (cf. Table 13). TABLE 13______________________________________Synthesis of L-Trp-Gly as a function of theL-Trp-NH.sub.2 concentrationL-Trp-NH.sub.2 Yield Selectivity Conversion(mM) (%) (%) (%)______________________________________24.4 51 72 7147.6 59 66 8995.2 59 59 100140 55 56 97182 51 54 94298 36 56 63400 12 53 22______________________________________ c) Influence of polar substances in the reaction mixture on L-Trp-Gly synthesis Batches for L-Trp-Gly synthesis from L-Trp-NH 2 (50 mM) and glycine (500 mM, pH 10) in the presence of ADL acylase were compounded with various ionic and uncharged polar compounds in a high concentration and incubated 19 hours at 25° C. The acylase was partially purified by means of salting-out chromatography at 2.6 U/ml and used as pure enzyme after chromatography on Mono-Q at 1.5 U/ml. Thereafter, the content of tryptophane compounds in the reaction mixtures was determined as described in a). Table 14 shows that at 50% (w/v) glycerin, a selectivity which is greater by 12% points is achieved with the same yield as in the reference batch. TABLE 14______________________________________Influence of ionic and uncharged polar substanceson the L-Trp-Gly synthesis Concen- Selec- Conver- tration tivity Yield sionSubstance (% w/v) (%) (%) (%)______________________________________Partially purifiedAcylase:Control -- 67 64 96Potassium 5.0 59 59 100phosphatePotassium 10.0 48 48 100phosphateAmmonium 12.5.sup.a) 65 65 100sulfateAmmonium 25.0.sup.a) 63 68 89sulfateEthanol 10.0.sup.b) 66 66 100 " 20.0.sup.b) 72 64 89Glycerin 25.0 71 71 100 " 50.0 79 65 83Pure acylase:Control -- 73 62 85glycerine 25 78 56 72 " 50 83 54 66______________________________________ .sup.a) % saturation .sup.b) % v/v EXAMPLE 16 Preparation of L-Trp-dipeptides from L-Trp-NH 2 and D- and L-amino acids An investigation was made as to whether D- and L-amino acids can also function instead of glycine as amino components for the dipeptide synthesis from L-Trp-NH 2 in the presence of ADL acylase. The D- and L-amino acids were used close to their solubility limit or at a maximum of 0.5M in tests with the following composition: 100-500 mM D- or L-amino acid 50 mM L-Trp-NH 2 2.6 U/ml acylase (purified by means of salting-out chromatography) pH 10. The batches were incubated for 19 hours at 25° C. and then tested with an amino acid analyzer and by thin-layer chromatography for their content of ninhydrin-positive compounds (mobile solvent methylethylketone/pyridine/water/glacial acetic acid in a ratio of 70/15/15/2. Amino acids as well as the dipeptides L-Trp-Gly, L-Trp-D,L-alanine and L-Trp-D,Lphenylalanine were identified in comparison to standard solutions and quantified. Additional peaks in the remaining analyzer chromatograms were also interpreted analogously as dipeptides and their concentration estimated using the average specific peak area of above-named standard solutions (+10% standard deviation). As is apparent from Table 15, approximately 40% and 15% of the L-Trp-NH 2 is converted to the corresponding dipeptide with the amino acids D-methionine and D-cysteine. TABLE 15______________________________________D- and L-amino acids as amino components forthe synthesis of tryptophyl dipeptides Conver- Selec- Type ofAmino Conc. Yield sion tivity calcu-components (mM) (%) (%) (%) lation______________________________________Glycine 500 66 100 66 *D-methionine 300 39 99 40 **D-leucine 150 23 100 23 **L-methionine 300 22 95 22 **D-alanine 500 22 87 26 *D-cysteine 500 15 85 17 **L-alanine 500 12 99 12 *D-valine 500 12 91 13 **D-phenylalanine 150 11 59 18 *D-serine 500 10 100 10 **L-cysteine 500 3 94 3 **L-leucine 150 0 100 0 --L-valine 500 0 93 0 --L-phenylalanine 150 0 100 0 --D-tryptophane 100 0 100 0 --L-tryptophane 100 0 100 0 --D-histidine 150 0 83 0 --L-histidine 150 0 91 0 --D-proline 500 0 100 0 --L-proline 500 0 100 0 --L-lysine 500 0 100 0 --L-arginine 150 0 100 0 --L-glutamic acid 500 0 77 0 --______________________________________ *Using it's own calibration standard **average standard from calibrations with 4 tryptophyl dipeptides (see above) EXAMPLE 17 Enantioselectivity of the tryptophyl dipeptide synthesis with N-acetyldehydroleucine acylase The stereospecificity of ADL acylase in the synthesis of dipeptides was investigated as regards the carboxyl component Trp-NH 2 and the amino component methionine. The batches described in the following were incubated 25 hours at 25° C. 50 mM L- or D,L-Trp-NH 2 300 mM D- or L-methionine or 500 mM glycine 2.6 U/ml acylase pH 10 The concentrations of amino acid and of dipeptide were determined as described in Example 16. The acylase prefers the L enantiomer of Trp-NH 2 as carboxyl component and the D form of methionine as amino component (cf. Table 16). TABLE 16__________________________________________________________________________Dipeptide synthesis as a function of thestereoconfiguration of the starting materialsTrp-NH.sub.2 Amino-component/ t.sub.r Yield Conv. SelectivityStereo Config. Conc. (mM) Dipeptide min (%) (%) (%)__________________________________________________________________________L Gly/500 L-Trp-Gly 49.77 65 100 65D,L Gly/500 D,L-Trp-Gly 49.79 60 100 60L L-Met/300 L-Trp-L-Met 49.31 25 97 26L D-Met/300 L-Trp-D-Met 49.92 50 100 50D,L L-Met/300 L-Trp-L-Met 49.29 15 84 19D,L D-Met/300 L-Trp-D-Met 49.87 44 93*.sup.) 48*.sup.) D-Trp-D-Met 49.33 39 93*.sup.) 42*.sup.) Average 42 93 45__________________________________________________________________________ *.sup.) assuming the same conversion of both antipodes of the TrpNH.sub.2 Gly: glycine Met: methionine t.sub.r = retention time

A novel N-Acetyl-2,3-didehydroaminoacid-acylase is obtained by cultivating Zoogloea ramigera DSM 4306. The new enzyme can be used in a coupled enzyme system with an L-Leucinedehydrogenase for the enzymatic conversion of N-Acetyl-2,3-didehydroleucine to L-Leucine, D- or L-tryptophylglycine to D- or L-tryptophaneamide and glycine, as well as other tryptophanedipeptides to tryptophaneamides and free amino acids.

CROSS REFERENCE This application is a division of Ser. No. 400,755 filed Sept. 26, 1973, U.S. Pat. No. 3,852,370 which was a continuation in part of Ser. No. 249,963 filed May 3, 1972, and now abandoned. BACKGROUND OF THE INVENTION 1. Field of the Invention This application relates to the oxidative dehydrogenation of organic compounds in the presence of oxygen, halogen and a particular catalyst. The catalyst of this invention comprises those selected from the group consisting of iron ferrite which has been modified by the addition thereto of a metal oxide comprising the oxides of cerium, zinc, manganese and lead and barium ferrite which has been modified by the addition thereto of a metal oxide comprising the oxides of zinc, manganese and lead. 2. Description of the Prior Art U.S. Pat. No. 3,303,234 discloses the oxidative dehydrogenation of organic compounds with a catalyst comprising barium ferrite. The oxidative dehydrogenation of organic compounds with catalyst comprising ferrites is also disclosed in U.S. Pat. Nos. 3,270,080; 3,284,536; 3,303,235; 3,303,236; 3,303,238; 3,308,182; 3,324,195; 3,334,152; 3,342,890; 3,420,911; 3,420,912; 3,428,703 and 3,440,229. SUMMARY OF THE INVENTION This invention relates to improved catalyst compositions and a process for oxidative dehydrogenation of organic compounds using the improved catalyst. The improved catalyst compositions comprise ferrites of iron having combined therewith as a catalyst modifier a metal oxide selected from the group consisting of CeO 2 , ZnO, MnO 2 and PbO or mixtures of these oxides and ferrites of barium having combined therewith as a catalyst modifier a metal oxide selected from the group consisting of ZnO, MnO 2 and PbO or mixtures of these oxides. This invention also relates to a process where these improved catalyst compositions are used in an oxidative dehydrogenation process where oxyge, an organic compound and a halogen are fed to a reactor containing the improved catalyst compositions. DESCRIPTION OF THE PREFERRED EMBODIMENT According to this invention an improved catalyst and a process utilizing the improved catalyst are provided for the dehydrogenation of aliphatic organic compounds to obtain corresponding unsaturated derivatives thereof. One of the primary objectives in catalyst development is to produce more active catalysts which retain a high degree of selectivity of the products desired. Such catalysts generally provide improved processes resulting in higher yields of the desired product. The catalyst of the present invention comprise iron ferrite in which there has been incorporated a promoting amount of a metal oxide selected from the group consisting of CeO 2 , ZnO, MnO 2 , PbO and mixtures thereof, and barium ferrite in which there has been incorporated a promoting amount of a metal oxide selected from the group consisting of ZnO, MnO 2 , PbO and mixtures thereof. The improved process of the present invention comprises feeding oxygen or an oxygen containing gas, a halogen and the organic compound to be dehydrogenated to a reactor containing the iron ferrite or barium ferrite which has been modified as specified above by the addition of a promoting amount of an oxide of the metals, cerium, zinc, manganese and lead. The iron ferrite and barium are known commercial products in the improved catalyst of the present invention, the iron ferrite or barium ferrite component will form a major proportion of the catalyst composition with the metal oxide promoter being present in a minor proportion. Thus, the catalyst composition of the present invention can contain up to 45 percent by weight cerium oxide, zinc oxide, manganese oxide, lead oxide, or mixtures thereof with the remainder being essentially iron ferrite, barium ferrite or mixtures thereof. Generally, it has been found preferable to incorporate from 0.35 to 1.3 moles of the metal oxide modifier per mole of iron oxide or barium oxide in the catalyst composition. The organic compounds to be dehydrogenated according to the process of this invention are hydrocarbons of 4 to 7 carbon atoms and preferably hydrocarbons selected from the group consisting of saturated hydrocarbons, cycloaliphatics, monoolefins, diolefins and mixtures thereof of 4 to 5 or 6 carbon atoms having a straight chain of at least 4 carbon atoms. Examples of preferred feed materials are butene-1, cis-butene-2, trans-butene-2, 2-methyl butene-1, 2-methyl butene-2, 3-methyl butene-1, n-butane butadiene-1,3, methyl butane, cyclohexane, cyclohexene, 2-methyl pentene-1, 2-methyl pentene-2 and mixtures thereof. For example, n-butane may be converted to a mixture of butene-1 and butene-2 or may be converted to a mixture of butene-1, butene-2 and/or butadiene-1,3. A mixture of n-butane and butene-2 may be converted to butadiene-1,3 or to a mixture of butadiene-1,3 together with some butene-2 and butene-1. Vinylacetylene may be present as a product, particularly when butadiene-1,3 is used as a feedstock. Thus, the process of this invention is useful in converting hydrocarbons to less saturated hydrocarbons of the same number of carbon atoms. The major proportion of the hydrocarbons converted will be to less saturated hydrocarbons of the same number of carbon atoms. Particularly, the preferred products are butadiene-1,3 and isoprene. Useful feeds may be mixed hydrocarbon streams such as refinery streams, or the olefin containing hydrocarbon mixture obtained as the product from the dehydrogenation of hydrocarbons. In the production of gasoline from higher hydrocarbons either thermal or catalytic cracking a hydrocarbon stream containing predominantly hydrocarbons of four carbon atoms may be produced and comprise a mixture of butenes together with butadiene, butane, isobutane, isobutylene and other ingredients in minor amounts. These and other refinery by-products which contain normal, ethylenically unsaturated hydrocarbons are useful as starting materials for the present process. Although various mixtures of hydrocarbons are useful, the preferred hydrocarbon feed contains at least 50 weight percent of a hydrocarbon selected from the group consisting of butene-1, butene-2, n-butane, butadiene-1,3, 2-methyl butene-1, 2-methyl butene-2, 2-methyl butene-3 and mixtures thereof, and more preferably contains at least 70 weight percent, of one or more of these hydrocarbons (with both of these percentages being based on the total weight of the organic composition of the feed to the reactor). Any remainder may be, for example, essentially aliphatic hydrocarbons. This invention is particularly useful to provide a process whereby the major product of the hydrocarbon converted is a dehydrogenated hydrocarbon product having the same number of carbon atoms as the hydrocarbon fed. Diluents such as nitrogen, helium, or other gases which are not dehydrogenated or which are dehydrogenated only to a limited extent may be used in the process of the present invention. Mixtures of diluents may also be employed. The halogen fed to the dehydrogenation zone may be either elemental halogen or any compound of halogen which would liberate under the conditions of reaction. Suitable sources of halogens are such as hydrogen iodide, hydrogen bromide. and hydrogen chloride; aliphatic halides such as ethyl iodide, methyl bromide, 1,2-dibromo ethane, ethyl bromide, amyl bromide and allyl bromide; cyclo-aliphatic halides such as cyclohexylbromide; aromatic halides such as benzyl bromide; halohydrins such as ethylene bromohydrin; halogen substituted aliphatic acids such as bromoacetic acid; ammonium iodide; ammonium bromide; ammonium chloride; organic amine halide salts such a methyl amine hydrobromide; and the like. Mixtures of various sources of halogens may be used. The preferred sources of halogen are iodine, bromine and chlorine and compounds thereof such a hydrogen bromine, hydrogen iodide, hydrogen chloride, ammonium bromide, ammonium iodide, ammonium chloride, alkyl halides of 1 to 6 carbon atoms and mixtures thereof with the chloride compounds being particularly preferred, with excellent results being obtained from the use of chlorine or hydrogen chloride. When terms such as halogen liberating materials or halogen materials are used in the specification and claims, this includes any source of halogen such as elemental halogen, hydrogen halides or ammonium halides. The amount of halogen calculated as elemental halogen, may be as little as about 0.0001 or less mole of halogen per mole of the hydrocarbon compound to be dehydrogenated to as much as 0.2 or 0.5 moles of halogen per mole of hydrocarbon compound to be dehydrogenated. The preferred range is from 0.0001 to 0.09 moles of halogen per mole of hydrocarbon to be dehydrogenated. Oxygen will be present in the reaction zone in an amount within the range of 0.2 to 2.5 moles of oxygen per mole of hydrocarbon to be dehydrogenated. Generally, better results may be obtained if the oxygen concentration is maintained between about 0.25 and about 1.6 moles of oxygen per mole of hydrogen to be dehydrogenated, such as between 0.35 and 1.3 moles of oxygen per mole of hydrocarbon to be dehydrogenated. The oxygen may be fed to the reactor as pure oxygen, as air, as oxygen-enriched air, oxygen mixed with diluents, etc. Based on the total gaseous mixture entering the reactor, the oxygen normally will be present in an amount from about 0.5 to 25 volume percent of the total gaseous mixture, and more usually will be present in an amount from about 1 to 50 volume percent of the total. The total amount of oxygen utilized may be introduced into the gaseous mixture entering the catalytic zone or it can be added in increments, such as different sections of the reactor. The above described proportions of oxygen employed are based on the total amount of oxygen used. The oxygen may be added directly to the reactor or it may be premixed, for example, with a diluent or steam. The temperature for the dehydrogenation reaction will be greater than 400° C, and the maximum temperature in the reactor may be about 750° C or perhaps higher under certain circumstances. Excellent results are obtained within the range of about 500°C to 600°C. The temperatures are measured at the maximum temperature in the reactor. The dehydrogenation reaction may be carried out at atmospheric pressure, super-atmospheric pressure or at sub-atmospheric pressure. The total pressure of the system will normally be about or in excess of atmospheric pressure although sub-atmospheric pressure may also desirably be used. Generally, the total pressure will be between about 4 psia and about 100 or 125 psia. Preferably the total pressure will be less than about 75 psia and excellent results will be otained at about atmospheric pressure. Conveniently, the oxygen may be added as air with any nitrogen or other gas acting as a diluent for the system. Mixtures of diluents may be employed. Volatile compounds which are not dehydrogenated or which are dehydrogenated only to a limited extent may be present as a diluent. The reaction mixture may contain a quantity of steam. The range generally being between about 2 to 40 moles of steam per mole of hydrocarbon to be dehydrogenated if steam is employed. The functions of the steam are several fold, as described in the patent references mentioned hereinbefore. However, the steam does act as a diluent. Diluents generally may be used in the same quantities specified for the steam. Excellent results are obtained when the gaseous composition fed to the reactor consists essentially of hydrocarbons, inert diluents and oxygen as the sole oxidizing agent. The gaseous reactants may be conducted through the reaction chamber at a fairly wide range of flow rates. The optimum flow rate will be dependent upon such variables as the temperature of reaction, pressure, particle size and whether a fluid bed or a fixed bed reactor is utilized. Desirable flow rates may be established by one skilled in the art. Generally, the flow rates will be within the range of about 0.10 to 25 liqiud volumes of the hydrocarbon to be dehydrogenated per volume of reactor containing catalyst per hour (referred to as LHSV), wherein the volumes of hydrocarbon are calculated at standard conditions of 25° C and 760 millimeters of mercury. Usually, the LHSV will be between 0.15 and about 5 or 10. For calculation, the volume of reactor containing catalyst is that volume of reactor space excluding the volume displaced by the catalyst for example if a reactor has a particular volume of cubic feet of weight space, when that void space is filled with catalyst particles the original void space is the volume of reactor containing catalyst for the purpose of calculating the flow rate. The gaseous hourly space flow velocity (GHSV) is the volume of the hydrocarbon to be dehydrogenated in the form of vapor calculated under standard conditions of 25° C and 760 millimeters of mercury per volume of reactor space containing catalyst per hour. Generally, the GHSV will be between about 25 and 6400, and excellent results have been obtained between about 38 and 3800. Suitable contact times are, for example, from about 0.001 or higher to about 5 or 10 seconds with particularly good results being obtained between 0.01 and 3 seconds. The contact time is the calculated dwell time of the reaction mixture in the reaction zone, assuming the moles of product mixture are equivalent to the moles of feed mixture. For the purpose of calculation of residence times, the reaction zone is the portion of the reactor containing catalyst. As mentioned hereinbefore, the catalyst composition of the present invention comprises iron ferrite or barium ferrite combined together with the specified metal oxide selected from the group consisting of CeO 2 , ZnO, MnO 2 , PbO and mixtures thereof. Based on the total active catalyst components, the metal oxide will be present in a range of 0.3 to 1.3 moles to mole of the ferrite component. The catalyst composition can also include inert binding agents and fillers, but these will not ordinarily exceed about 50 percent or 60 percent by weight of the catalytic composition including active catalyst components and inert binding agents or fillers. The catalyst will be by definition present in a catalytic amount. The amount of catalyst ordinarily will be greater than ten square feed of catalyst surface per cubic foot of reaction zone containing catalyst. The term catalyst is meant to mean total active catalyst components and does not include inert binding agents or fillers. Of course, the amount of catalyst may be much greater, particularly when irregular surface catalyst are used. When the catalyst is in the form of particles, either supported or unsupported, the amount of catalyst surface may be expressed in terms of the surface area per unit weight of any particular volume of catalyst particles. The ratio of catalyst surface to weight will be dependent upon several factors, including the particle size distribution, apparent bulk density of the particles, the carrier etc. Typical values for the surfaced to weight ratio are such as about one-half to 200 square meters per gram although higher and lower values may be used. The dehydrogenation reactor may be of the fixed bed of fluid bed type. Conventional reactors for the production of unsaturated hydrocarbons are satisfactory. Excellent results have been obtained by packing the reactor with catalyst particles as the method of introducing the catalytic surface. The catalytic surface may be introduced as such or it may be deposited on a carrier by methods known in the art such as by preparing an aqueous solution or dispersion of a catalytic material and mixing the carrier with the solution or dispersion until the active ingredients are coated on the carrier. If a carrier is utilized, very useful carriers are silicon carbide, pumice and like. When carriers are used, the amount of catalyst on the carrier will generally be between about 5 to 75 weight percent of the total weight of active catalytic material plus carrier. Another method for introducing the required surface is to utilize as a reactor a small diameter tube wherein the tube wall is catalytic or is coated with catalytic material. Other methods may be utilized to introduce the catalytic surface such as by the use of rods, wires, mesh, or shreds and the like of catalytic material. In the following examples will be found specific embodiments of the invention and details employed in the practice of the invention. Percent conversion refers to the moles of hydrocarbon consumed per 100 moles of hydrocarbon fed to the reactor, percent selectivity refers to the moles of product formed per 100 moles of hydrocarbon consumed, and percent yield refers to the moles of product formed per 100 moles of hydrocarbon fed. All other percentages are be weight unless expressed otherwise. EXAMPLES 1-5 Barium ferrite (Columbian Carbon Company EG No. 4) was used as the catalyst in Example 1. In Examples 2 - 5 the oxides of zinc, manganese and lead were incorporated with the barium ferrite catalyst respectively in the amounts shown in Table I. The barium ferrite or barium ferrite containing the metal oxide was coated on 4 to 8 mesh alumina pellets in an amount of roughly 30 percent of weight of the barium ferrite or barium ferrite incorporating the metal oxide based on the total weight. In each of the Examples 1-5, n-butane was dehydrogenated at atmospheric pressure in a Vycor glass reactor containing therein a 50 cc. catalyst bed supported on a 1-inch deep layer of Rashig rings. The reactants, n-butane, oxygen, nitrogen and chlorine were introduced into the top of the glass reactor, and the effluent gases were withdrawn from the bottom of the reactor. Samples of the effluent gases were analyzed in a vapor chromatograph. The mixture of n-butane, oxygen, nitrogen and chlorine was fed to the reactor in an amount of 1.3 moles of oxygen, 0.3 moles of chlorine and 15 moles of nitrogen per mole of n-butane. The LHSV was 0.25 and the maximum temperature in the reactor was 580° C. The results obtained in Examples 1- are shown in Table I. TABLE I__________________________________________________________________________ Percent Percent Total Percent Yield of Yield of PercentExampleCatalyst Promoter Conversion Butenes Butadiene Yield__________________________________________________________________________1 BaFe.sub.2 O.sub.4 None 73 32 19 512 BaFe.sub.2 O.sub.4 ZnO* 74 30 24 543 BaFe.sub.2 O.sub.4 MnO.sub.2 * 86 22 28 504 BaFe.sub.2 O.sub.4 PbO* 80 27 26 535 BaFe.sub.2 O.sub.4 PbO/ZnO** 73 34 24 58__________________________________________________________________________ *Present in amount of 25 weight percent based on total weight of BaFe.sub.2 O.sub.4 and promoter. **Mixture of 15 weight percent PbO, 10 weight percent ZnO with mixture present in amount of 25 weight percent based on total Ba ferrite and oxid modifier. In Examples 2-5, the yield of butadiene was dramatically increased over the yield of butadiene for the control Example 1. In Examples 2, 4 and 5 the total yield of butenes and butadiene were increased in comparison to the total yield of the control Example 1. EXAMPLES 6 - 8 The procedures of Examples 1 - 5 were repeated with the exception that iron ferrite, Fe 3 O 4 was used in Example 6 as the catalyst and Fe 3 O 4 containing CeO was used in Example 7, Fe 3 O 4 containing PbO and ZnO was used in Example 8. Otherwise, the conditions and process steps were identical to those of Examples 1 - 5. The results obtained from Examples 6 - 8 are shown in Table II. TABLE II__________________________________________________________________________ Percent Percent Total Percent Yield of Yield of PercentExampleCatalyst Promoter Conversion Butenes Butadiene Yield__________________________________________________________________________6 Fe.sub.3 O.sub.4 None 82 28 28 567 Fe.sub.3 O.sub.4 CeO* 83 31 32 638 Fe.sub.3 O.sub.4 PbO/ZnO** 78 28 35 63__________________________________________________________________________ *Present in amount of 25 weight percent based on total weight of Fe ferrite and modifier. **Mixture of 15 weight percent PbO and 10 weight percent ZnO with the mixture being present in amount of 25 weight percent based on total weigh of Fe ferrite and the mixture of PbO and ZnO. Examples 7 and 8 showed increased yields of butadiene as well as total yields of butenes and butadiene in comparison to the control Example 6.

Catalysts comprising ferrites of iron modified with oxides of cerium, zinc, manganese and lead and ferrites of barium modified with oxides of zinc, manganese and lead and a process of oxidative dehydrogenation of organic compounds in the presence of these catalysts compositions and cocatalyst such as chlorine.

This application is a continuation-in-part of: U.S. application Ser. No. 417,951, filed Oct. 6, 1989, now abandoned; U.S. application Ser. No. 418,050, filed Oct. 6, 1989, now abandoned; and U.S. application Ser. No. 454,789, filed Dec. 21, 1989,now abandoned. FIELD OF THE INVENTION This invention relates to azeotrope-like mixtures of dichloropentafluoropropane and a hydrocarbon containing six carbon atoms. These mixtures are useful in a variety of vapor degreasing, cold cleaning, and solvent cleaning applications including defluxing and dry cleaning. CROSS-REFERENCE TO RELATED APPLICATIONS Co-pending, commonly assigned patent application Ser. No. 418,059, filed Oct. 6, 1989, discloses azeotrope-like mixtures of 1,1-dichloro-2,2,3,3,3-pentafluoropropane and alkane having six carbon atoms. Co-pending, commonly assigned patent application Ser. No. 417,951, filed Oct. 6, 1989, now abandoned, discloses azeotrope-like mixtures of 1,3-dichloro-1,1,2,2,3-pentafluoropropane and cyclohexane. Co-pending, commonly assigned patent application Ser. No. 454,789, filed Dec. 21, 1989, now abandoned discloses azeotrope-like mixtures of dichloropentafluoropropane and cyclohexane. BACKGROUND OF THE INVENTION Fluorocarbon based solvents have been used extensively for the degreasing and otherwise cleaning of solid surfaces, especially intricate parts and difficult to remove soils. In its simplest form, vapor degreasing or solvent cleaning consists of exposing a room temperature object to be cleaned to the vapors of a boiling solvent. Vapors condensing on the object provide clean distilled solvent to wash away grease or other contamination. Final evaporation of solvent from the object leaves the object free of residue. This is contrasted with liquid solvents which leave deposits on the object after rinsing. A vapor degreaser is used for difficult to remove soils where elevated temperature is necessary to improve the cleaning action of the solvent, or for large volume assembly line operations where the cleaning of metal parts and assemblies must be done efficiently. The conventional operation of a vapor degreaser consists of immersing the part to be cleaned in a sump of boiling solvent which removes the bulk of the soil, thereafter immersing the part in a sump containing freshly distilled solvent near room temperature, and finally exposing the part to solvent vapors over the boiling sump which condense on the cleaned part. In addition, the part can also be sprayed with distilled solvent before final rinsing. Vapor degreasers suitable in the above-described operations are well known in the art. For example, Sherliker et al. in U.S. Pat. No. 3,085,918 disclose such suitable vapor degreasers comprising a boiling sump, a clean sump, a water separator, and other ancillary equipment. Cold cleaning is another application where a number of solvents are used. In most cold cleaning applications, the soiled part is either immersed in the fluid or wiped with cloths soaked in solvents and allowed to air dry. Recently, nontoxic nonflammable fluorocarbon solvents like trichlorotrifluoroethane, have been used extensively in degreasing applications and other solvent cleaning applications. Trichlorotrifluoroethane has been found to have satisfactory solvent power for greases, oils, waxes and the like. It has therefore found widespread use for cleaning electric motors, compressors, heavy metal parts, delicate precision metal parts, printed circuit boards, gyroscopes, guidance systems, aerospace and missile hardware, aluminum parts, etc. The art has looked towards azeotropic compositions having fluorocarbon components because the fluorocarbon components contribute additionally desired characteristics, like polar functionality, increased solvency power, and stabilizers. Azeotropic compositions are desired because they do not fractionate upon boiling. This behavior is desirable because in the previously described vapor degreasing equipment with which these solvents are employed, redistilled material is generated for final rinse-cleaning. Thus, the vapor degreasing system acts as a still. Therefore, unless the solvent composition is essentially constant boiling, fractionation will occur and undesirable solvent distribution may act to upset the cleaning and safety of processing. Preferential evaporation of the more volatile components of the solvent mixtures, which would be the case if they were not an azeotrope or azeotrope-like, would result in mixtures with changed compositions which may have less desirable properties, such as lower solvency towards soils, less inertness towards metal, plastic or elastomer components, and increased flammability and toxicity. The art is continually seeking new fluorocarbon based azeotropic mixtures or azeotrope-like mixtures which offer alternatives for new and special applications for vapor degreasing and other cleaning applications. Currently, fluorocarbon-based azeotrope-like mixtures are of particular interest because they are considered to be stratospherically safe substitutes for presently used fully halogenated chlorofluorocarbons. The latter have been implicated in causing environmental problems associated with the depletion of the earth's protective ozone layer. Mathematical models have substantiated that hydrochlorofluorocarbons, like dichloropentafluoropropane, have a much lower ozone depletion potential and global warming potential than the fully halogenated species. Accordingly, it is an object of the present invention to provide novel environmentally acceptable azeotrope-like compositions which are useful in a variety of industrial cleaning applications. It is another object of this invention to provide azeotrope-like compositions which are liquid at room temperature and which will not fractionate under conditions of use. Other objects and advantages of the invention will become apparent from the following description. SUMMARY OF THE INVENTION The invention relates to novel azeotrope-like compositions which are useful in a variety of industrial cleaning applications. Specifically the invention relates to compositions of dichloropentafluoropropane and a hydrocarbon containing six carbon atoms which are essentially constant boiling, environmentally acceptable and which remain liquid at room temperature. DETAILED DESCRIPTION OF THE INVENTION In accordance with the invention, novel azeotrope-like compositions have been discovered consisting essentially of from about 72 to about 99.99 weight percent dichloropentafluoropropane and from about 0.01 to about 28 weight percent of a hydrocarbon containing six carbon atoms (HEREINAFTER referred to as "C 6 hydrocarbon") wherein the azeotrope-like components of the composition consist of dichloropentafluoropropane and a C 6 hydrocarbon and boil at about 52.5° C. ± about 3.5° C. at 748 mm Hg and preferably boil at about 52.3° C. ± about 3.3° C. and more preferably ± about 2.9° C. As used herein, the term "C 6 hydrocarbon" shall refer to aliphatic hydrocarbons having the empirical formula C 6 H 14 and cycloaliphatic or substituted cycloaliphatic hydrocarbons having the empirical formula C 6 H 12 ; and mixtures thereof. Preferably, the term C 6 hydrocarbon refers to the following subset including: n-hexane, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, 2,3-dimethylbutane, methylcyclopentane, cyclohexane, commercial isohexane* (typically, the percentages of the isomers in commercial isohexane will fall into one of the two following formulations designated grade 1 and grade 2: 0rade 1: 35-75 weight percent 2-methylpentane, 10-40 weight percent 3-methylpentane, 7-30 weight percent 2,3-dimethylbutane, 7-30 weight percent 2,2-dimethylbutane, and 0.1-10 weight percent n-hexane, and up to about 5 weight percent other alkane isomers; the sum of the branched chain six carbon alkane isomers is about 90 to about 100 weight percent and the sum of the branched and straight chain six carbon alkane isomers is about 95 to about 100 weight percent; grade 2: 40-55 weight percent 2-methylpentane, 15-30 weight percent 3-methylpentane, 10-22 weight percent 2,3-dimethylbutane, 9-16 weight percent 2,2-dimethylbutane, and 0.1-5 weight percent n-hexane; the sum of the branched chain six carbon alkane isomers is about 95 to about 100 weight percent and the sum of the branched and straight chain six carbon alkane isomers is about 97 to about 100 weight percent) and mixtures thereof. Dichloropentafluoropropane exists in nine isomeric forms: (1) 2,2-dichloro-1,1,1,3,3-pentafluoro-propane (HCFC-225a); (2) 1,2-dichloro-1,2,3,3,3-pentafluoropropane (HCFC-225ba); (3) 1,2-dichloro-1,1,2,3,3-pentafluoropropane (HCFC-225bb); (4) 1,1-dichloro-2,2,3,3,3-pentafluoropropane (HCFC-225ca); (5) 1,3-dichloro-1,1,2,2,3-pentafluoropropane (HCFC-225cb); (6) 1,1-dichloro-1,2,2,3,3-pentafluoropropane (HCFC-225cc); (7) 1,2-dichloro-1,1,3,3,3-pentafluoropropane (HCFC-225d); (8) 1,3-dichloro-1,1,2,3,3-pentafluoropropane (HCFC-225ea); and (9) 1,1-dichloro-1,2,3,3,3-pentafluoropropane (HCFC-225eb). For purposes of this invention, dichloropentafluoropropane will refer to any of the isomers or an admixture of the isomers in any proportion. The 1,1-dichloro-2,2,3,3,3-pentafluoropropane and 1,3-dichloro-1,1,2,2,3-pentafluoropropane isomers, however, are the preferred isomers. The dichloropentafluoropropane component of the invention has good solvent properties. The hydrocarbon component also has good solvent capabilities; enhancing the solubility of oils. Thus, when these components are combined in effective amounts, an efficient azeotropic solvent results. When the C 6 hydrocarbon is 2-methylpentane, the azeotrope-like compositions of the invention consist essentially of from about 72 to about 92 weight percent dichloropentafluoropropane and from about 8 to about 28 weight percent 2-methylpentane and boil at about 51.1° C. ± about 1.8° C. at 750 mm Hg. When the C 6 hydrocarbon is 3-methylpentane, the azeotrope-like compositions of the invention consist essentially of from about 74 to about 96 weight percent dichloropentafluoropropane and from about 4 to about 26 weight percent 3-methylpentane and boil at about 51.6° C. ± about 2.1° C. at 745 mm Hg. When the C 6 hydrocarbon is commercial isohexane grade 1, the azeotrope-like compositions of the invention consist essentially of from about 72 to about 92 weight percent dichloropentafluoropropane and from about 8 to about 28 weight percent commercial isohexane grade 1 and boil at about 50.5° C. ± about 2.5° C. at 750 mm Hg. When the C 6 hydrocarbon is commercial isohexane grade 2, the azeotrope-like compositions of the invention consist essentially of from about 72 to about 92 weight percent dichloropentafluoropropane and from about 8 to about 28 weight percent commercial isohexane grade 2 and boil at about 50.5° C. ± about 2.5° C. at 750 mm Hg. When the C 6 hydrocarbon is n-hexane, the azeotrope-like compositions of the invention consist essentially of from about 77.5 to about 99.5 weight percent dichloropentafluoropropane and from about 0.5 to about 22.5 weight percent n-hexane and boil at about 53.2° C. ± about 2.2° C. at 760 mm Hg. When the C 6 hydrocarbon is methylcyclopentane, the azeotrope-like compositions of the invention consist essentially of from about 85 to about 99.99 weight percent dichloropentafluoropropane and from about 0.01 to about 15 weight percent methylcyclopentane and boil at about 52.7° C. ± about 2.4° C. at 745 mm Hg. When the C 6 hydrocarbon is cyclohexane, the azeotrope-like compositions of the invention consist essentially of from about 90 to about 99.99 weight percent dichloropentafluoropropane and from about 0.01 to about 10 weight percent cyclohexane and boil at about 53.5° C. ± about 2.7° C. at 760 mm Hg. When the dichloropentafluoropropane component is 225ca and the C 6 hydrocarbon is cyclohexane, the azeotrope-like compositions of the invention consist essentially of from about 94 to about 99.99 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 0.01 to about 6 weight percent cyclohexane and boil at about 50.6° C. ± about 0.5° C. and preferably ± about 0.3° C. and more preferably ± about 0.2° C. at 748 mm Hg. In a preferred embodiment of the invention utilizing 225ca and cyclohexane, the azeotrope-like compositions consist essentially of from about 95 to about 99.99 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 0.01 to about 5 weight percent cyclohexane. In the most preferred embodiment of the invention utilizing 225ca and cyclohexane, the azeotrope-like compositions consist essentially of from about 96 to about 99.99 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 0.01 to about 4 weight percent cyclohexane. In another embodiment of the invention utilizing 225ca and cyclohexane, the azeotrope-like compositions consist essentially of from about 97 to about 99.99 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 0.01 to about 3 weight percent cyclohexane. In yet another embodiment of the invention utilizing 225ca and cyclohexane, the azeotrope-like compositions consist essentially of from about 98 to about 99.99 weight percent 1,1-dichloro-2,2,2,3,3-pentafluoropropane and from about 0.01 to about 2 weight percent cyclohexane. When the dichloropentafluoropropane component is 225ca and the C 6 hydrocarbon is 2-methylpentane, the azeotrope-like compositions of the invention consist essentially of from about 83 to about 94 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 6 to about 17 weight percent 2-methylpentane and boil at about 49.8° C. ± about 0.5° C. 751 mm Hg. In a preferred embodiment utilizing 225ca and 2-methylpentane, the azeotrope-like compositions of the invention consist essentially of from about 85 to about 92 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 8 to about 15 weight percent 2-methylpentane. In a more preferred embodiment utilizing 225ca and 2-methylpentane, the azeotrope-like compositions of the invention consist essentially of from about 85 to about 91 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 9 to about 15 weight percent 2-methylpentane. When the dichloropentafluoropropane component is 225ca and the C 6 hydrocarbon is 3-methylpentane, the azeotrope-like compositions of the invention consist essentially of from about 85.5 to about 96.5 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 3.5 to about 14.5 weight percent 3-methylpentane and boil at about 50.0° C. ± about 0.5° C. at 744 mm Hg. In a preferred embodiment utilizing 225ca and 3-methylpentane, the azeotrope-like compositions of the invention consist essentially of from about 88 to about 95.5 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 4.5 to about 12 weight percent 3-methylpentane. When the dichloropentafluoropropane component is 225ca and the C 6 hydrocarbon is n-hexane, the azeotrope-like compositions of the invention consist essentially of from about 94 to about 99.5 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 0.5 to about 6 weight percent n-hexane and boil at about 50.5° C. ± about 0.2° C. at 746 mm Hg. In a preferred embodiment utilizing 225ca and n-hexane, the azeotrope-like compositions of the invention consist essentially of from about 95 to about 99.5 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 0.5 to about 5 weight percent n-hexane. In a more preferred embodiment utilizing 225ca and n-hexane, the azeotrope-like compositions of the invention consist essentially of from about 95 to about 99 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 1 to about 5 weight percent n-hexane. When the dichloropentafluoropropane component is 225ca and the C 6 hydrocarbon is commercial isohexane grade 1, the azeotrope-like compositions of the invention consist essentially of from about 77 to about 92.5 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 7.5 to about 23 weight percent commercial isohexane grade 1 and boil at about 48.5° C. ± about 1.5° C. at 737 mm Hg. In a preferred embodiment utilizing 225ca and commercial isohexane grade 1, the azeotrope-like compositions of the invention consist essentially of from about 80 to about 91 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 9 to about 20 weight percent commercial isohexane grade 1. In a more preferred embodiment utilizing 225ca and commercial isohexane grade 1, the azeotrope-like compositions of the invention consist essentially of from about 82 to about 90 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 10 to about 18 weight percent commercial isohexane grade 1. When the dichloropentafluoropropane component is 225ca and the C 6 hydrocarbon is commercial isohexane grade 2, the azeotrope-like compositions of the invention consist essentially of from about 77 to about 92.5 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 7.5 to about 23 weight percent commercial isohexane grade 2 and boil at about 48.5° C. ± about 1.5° C. at 737 mm Hg. In a preferred embodiment utilizing 225ca and commercial isohexane grade 2, the azeotrope-like compositions of the invention consist essentially of from about 80 to about 91 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 9 to about 20 weight percent commercial isohexane grade 2. In a more preferred embodiment utilizing 225ca and commercial isohexane grade 2, the azeotrope-like compositions of the invention consist essentially of from about 82 to about 90 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 10 to about 18 weight percent commercial isohexane grade 2. When the dichloropentafluoropropane component is 225ca and the C 6 hydrocarbon is methylcyclopentane, the azeotrope-like compositions of the invention consist essentially of from about 93 to about 99.99 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 0.01 to about 7 weight percent methylcyclopentane and boil at about 50.5° C. ± about 0.3° C. and preferably ± about 0.2° C. and more preferably ± about 0.1° C. at 743.9 mm Hg. In a preferred embodiment utilizing 225ca and methylcyclopentane, the azeotrope-like compositions of the invention consist essentially of from about 95 to about 99.99 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 0.01 to about 5 weight percent methylcyclopentane. In a more preferred embodiment utilizing 225ca and methylcyclopentane, the azeotrope-like compositions of the invention consist essentially of from about 96 to about 99.99 weight percent 1,1-dichloro-2,2,3,3,3-pentafluoropropane and from about 0.01 to about 4 weight percent methylcyclopentane. When the dichloropentafluoropropane component is 225cb and the C 6 hydrocarbon is 2-methylpentane, the azeotrope-like compositions of the invention consist essentially of from about 68 to about 85 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 15 to about 32 weight percent 2-methylpentane and boil at about 52.7° C. ± about 0.4° C. and preferably ± about 0.3° C. and more preferably ± about 0.2° C. at 750.4 mm Hg. In a preferred embodiment utilizing 225cb and 2-methylpentane, the azeotrope-like compositions of the invention consist essentially of from about 71 to about 83 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 17 to about 29 weight percent 2-methylpentane. When the dichloropentafluoropropane component is 225cb and the C 6 hydrocarbon is 3-methylpentane, the azeotrope-like compositions of the invention consist essentially of from about 71 to about 90 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 10 to about 29 weight percent 3-methylpentane and boil at about 53.4° C. ± about 0.4° C. and preferably ± about 0.3° C. and more preferably ± about 0.2° C. at 744 1 mm Hg. In a preferred embodiment utilizing 225cb and 3-methylpentane, the azeotrope-like compositions of the invention consist essentially of from about 74 to about 88 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 12 to about 26 weight percent 3-methylpentane. When the dichloropentafluoropropane component is 225cb and the C 6 hydrocarbon is methylcyclopentane, the azeotrope-like compositions of the invention consist essentially of from about 83.5 to about 96.5 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 3.5 to about 16.5 weight percent methylcyclopentane and boil at about 54.8° C. ± about 0.4° C. and preferably ± about 0.3° C. and more preferably ± at 746.2 mm Hg. In a preferred embodiment utilizing 225cb and methylcyclopentane, the azeotrope-like compositions of the invention consist essentially of from about 85 to about 96 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 4 to about 15 weight percent methylcyclopentane. In a more preferred embodiment utilizing 225cb and methylcyclopentane, the azeotrope-like compositions of the invention consist essentially of from about 86.5 to about 95 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 5 to about 13.5 weight percent methylcyclopentane. When the dichloropentafluoropropane component is 225cb and the C 6 hydrocarbon is n-hexane, the azeotrope-like compositions of the invention consist essentially of from about 76.5 to about 88.5 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 11.5 to about 23.5 weight percent n-hexane and boil at about 54.9° C. ± about 0.4° C. and preferably ± about 0.3° C. and more preferably ± about 0.2° C. at 756.4 mm Hg. In a preferred embodiment utilizing 225cb and n-hexane, the azeotrope-like compositions of the invention consist essentially of from about 77.5 to about 87.5 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 12.5 to about 22.5 weight percent n-hexane. When the dichloropentafluoropropane component is 225cb and the C 6 hydrocarbon is commercial isohexane grade 1, the azeotrope-like compositions of the invention consist essentially of from about 68 to about 85 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 15 to about 32 weight percent commercial isohexane grade 1 and boil at about 51.5° C. ± about 1.5° C. and preferably ± about 1.0° C. and more preferably ± about 0.5° C. at 750.4 mm Hg. When the dichloropentafluoropropane component is 225cb and the C 6 hydrocarbon is commercial isohexane grade 2, the azeotrope-like compositions of the invention consist essentially of from about 68 to about 85 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 15 to about 32 weight percent commercial isohexane grade 2 and boil at about 51.5° C. ± about 1.5° C. and preferably ± about 1.0° C. and more preferably ± about 0.5° C. at 750.4 mm Hg. When the dichloropentafluoropropane component is 225cb and the C 6 hydrocarbon is cyclohexane the azeotrope-like compositions of the invention consist essentially of from about 90 to about 99 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 1 to about 10 weight percent cyclohexane and boil at about 55.9° C. ± about 0.2° C. at 761 mm Hg. In a preferred embodiment utilizing 225cb and cyclohexane the azeotrope-like compositions of the invention consist essentially of from about 90.5 to about 98 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 2 to about 9.5 weight percent cyclohexane. In a more preferred embodiment utilizing 225cb and cyclohexane the azeotrope-like compositions of the invention consist essentially of from about 90.5 to about 97 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 3 to about 9.5 weight percent cyclohexane. In the most preferred embodiment utilizing 225cb and cyclohexane the azeotrope-like compositions of the invention consist essentially of from about 90.5 to about 96 weight percent 1,3-dichloro-1,1,2,2,3-pentafluoropropane and from about 4 to about 9.5 weight percent cyclohexane. The precise or true azeotrope compositions have not been determined but have been ascertained to be within the indicated ranges. Regardless of where the true azeotropes lie, all compositions within the indicated ranges, as well as certain compositions outside the indicated ranges, are azeotrope-like, as defined more particularly below. From fundamental principles, the thermodynamic state of a fluid is defined by four variables: pressure, temperature, liquid composition and vapor composition, or P-T-X-Y, respectively. An azeotrope is a unique characteristic of a system of two or more components where X and Y are equal at a stated P and T. In practice, this means that the components of a mixture cannot be separated during distillation, and therefore are useful in vapor phase solvent cleaning as described above. For purposes of this discussion, by azeotrope-like composition is intended to mean that the composition behaves like a true azeotrope in terms of its constant-boiling characteristics or tendency not to fractionate upon boiling or evaporation. Such compositions may or may not be a true azeotrope. Thus, in such compositions, the composition of the vapor formed during boiling or evaporation is identical or substantially identical to the original liquid composition. Hence, during boiling or evaporation, the liquid composition, if it changes at all, changes only minimally. This is contrasted with non-azeotrope-like compositions in which the liquid composition changes substantially during boiling or evaporation. Thus, one way to determine whether a candidate mixture is "azeotrope-like" within the meaning of this invention, is to distill a sample thereof under conditions (i.e. resolution--number of plates) which would be expected to separate the mixture into its separate components. If the mixture is non-azeotropic or non-azeotrope-like, the mixture will fractionate, i.e., separate into its various components with the lowest boiling component distilling off first, and so on. If the mixture is azeotrope-like, some finite amount of a first distillation cut will be obtained which contains all of the mixture components and which is constant boiling or behaves as a single substance. This phenomenon cannot occur if the mixture is not azeotrope-like, i.e., it is not part of an azeotropic system. If the degree of fractionation of the candidate mixture is unduly great, then a composition closer to the true azeotrope must be selected to minimize fractionation. Of course, upon distillation of an azeotrope-like composition such as in a vapor degreaser, the true azeotrope will form and tend to concentrate. It follows from the above that another characteristic of azeotrope-like compositions is that there is a range of compositions containing the same components in varying proportions which are azeotrope-like. All such compositions are intended to be covered by the term azeotrope-like as used herein. As an example, it is well known that at different pressures, the composition of a given azeotrope will vary at least slightly as does the boiling point of the composition. Thus, an azeotrope of A and B represents a unique type of relationship but with a variable composition depending on temperature and/or pressure. Accordingly, another way of defining azeotrope-like within the meaning of the invention is to state that such mixtures boil within about ± 3.5° C. (at 760 mm Hg) of the 52.5° C. boiling point disclosed herein. As is readily understood by persons skilled in the art, the boiling point of the azeotrope will vary with the pressure. In the process embodiment of the invention, the azeotrope-like compositions of the invention may be used to clean solid surfaces by treating said surfaces with said compositions in any manner well known in the art such as by dipping or spraying or use of conventional degreasing apparatus. As stated above, the azeotrope-like compositions dicussed herein are useful as solvents for various cleaning applications including vapor degreasing, defluxing, cold cleaning, dry cleaning, dewatering, decontamination, spot cleaning, aerosol propelled rework, extraction, particle removal, and surfactant cleaning applications. These azeotrope-like compositions are also useful as blowing agents, Rankine cycle and absorption refrigerants, and power fluids. The dichloropentafluoropropane and C 6 hydrocarbon components of the invention are known materials. Preferably, they should be used in sufficiently high purity so as to avoid the introduction of adverse influences upon the solvent or constant boiling properties of the system. Commercially available C 6 hydrocarbons may be used in the present invention. Most dichloropentafluoropropane isomers, like the preferred HCFC-225ca isomer, are not available in commercial quantities, therefore until such time as they become commercially available, they may be prepared by following the organic syntheses disclosed herein. For example, 1,1-dichloro-2,2,3,3,3-pentafluoropropane may be prepared by reacting 2,2,3,3,3-pentafluoro-1-propanol and p-toluenesulfonate chloride together to form 2,2,3,3,3-pentafluoropropyl-p-toluenesulfonate. Next, N-methylpyrrolidone, lithium chloride, and the 2,2,3,3,3,-pentafluoropropyl-p-toluenesulfonate are reacted together to form 1-chloro-2,2,3,3,3-pentafluoropropane. Finally, chlorine and 1-chloro-2,2,3,3,3-pentafluoropropane are reacted together to form 1,1-dichloro-2,2,3,3,3-pentafluoropropane. A detailed synthesis is set forth in Example 1. Synthesis of 2,2-dichloro-1,1,1,3,3-pentafluoropropane (225a). This compound may be prepared by reacting a dimethylformamide solution of 1,1,1-trichloro-2,2,2-trifluoromethane with chlorotrimethylsilane in the presence of zinc, forming 1-(trimethylsiloxy)-2,2-dichloro-3,3,3-trifluoro-N,N-dime thylpropylamine. The 1-(trimethylsiloxy)-2,2-dichloro-3,3,3-trifluoro-N,N-dimethyl propylamine is reacted with sulfuric acid to form 2,2-dichloro-3,3,3-trifluoropropionaldehyde. The 2,2-dichloro-3,3,3-trifluoropropionaldehyde is then reacted with sulfur tetrafluoride to produce 2,2-dichloro-1,1,1,3,3-pentafluoropropane. Synthesis of 1,2-dichloro-1,2,3,3,3-pentafluoropropane (225ba). This isomer may be prepared by the synthesis disclosed by O. Paleta et al., Bull. Soc. Chim. Fr., (6) 920-4 (1986). Synthesis of 1,2-dichloro-1,1,2,3,3-pentafluoropropane (225bb). The synthesis of this isomer is disclosed by M. Hauptschein and L. A. Bigelow, J. Am. Chem. Soc., (73) 1428-30 (1951). The synthesis of this compound is also disclosed by A. H. Fainberg and W. T. Miller, Jr., J. Am. Chem. Soc., (79) 4170-4, (1957). Synthesis of 1,3-dichloro-1,1,2,2,3-pentafluoropropane (225cb). The synthesis of this compound involves four steps. Part A--Synthesis of 2,2,3,3-tetrafluoropropyl-p-toluenesulfonate. 406 gm (3.08 mol) 2,2,3,3-tetrafluoropropanol, 613 gm (3.22 mol) tosylchloride, and 1200 ml water were heated to 50° C. with mechanical stirring. Sodium hydroxide (139.7 gm, 3.5 ml) in 560 ml water was added at a rate such that the temperature remained less than 65° C. After the addition was completed, the mixture was stirred at 50° C. until the pH of the aqueous phase was 6. The mixture was cooled and extracted with 1.5 liters methylene chloride. The organic layer was washed twice with 200 ml aqueous ammonia, 350 ml water, dried with magnesium sulfate, and distilled to give 697.2 gm (79%) viscous oil. Part B--Synthesis of 1,1,2,2,3-pentafluoropropane. A 500 ml flask was equipped with a mechanical stirrer and a Vigreaux distillation column, which in turn was connected to a dry-ice trap, and maintained under a nitrogen atmosphere. The flask was charged with 400 ml N-methylpyrrolidone, 145 gm (0.507 mol) 2,2,3,3-tetrafluoropropyl-p-toluenesulfonate (produced in Part A above), and 87 gm (1.5 mol) spray-dried KF. The mixture was then heated to 190°-200° C. for about 3.25 hours during which time 61 gm volatile product distilled into the cold trap (90% crude yield). Upon distillation, the fraction boiling at 25°-28° C. was collected. Part C--Synthesis of 1,1,3-trichloro-l,2,2,3,3-pentafluoropropane. A 22 liter flask was evacuated and charged with 20.7 gm (0.154 mol) 1,1,2,2,3-pentafluoropropane (produced in Part B above) and 0.6 mol chlorine. It was irradiated 100 minutes with a 450 W Hanovia Hg lamp at a distance of about 3 inches (7.6 cm). The flask was then cooled in an ice bath, nitrogen being added as necessary to maintain 1 atm (101 kPa). Liquid in the flask was removed via syringe. The flask was connected to a dry-ice trap and evacuated slowly (15-30 minutes). The contents of the dry-ice trap and the initial liquid phase totaled 31.2 g (85%), the GC purity being 99.7%. The product from several runs was combined and distilled to provide a material having b.p. 73.5°-74° C. Part D-Synthesis of 1,3-dichloro-1,1,2,2,3-pentafluoropropane. 106.6 gm (0.45 mol) of 1,1,3-trichloro-1,2,2,3,3-pentafluoropropane (produced in Part C above) and 300 gm (5 mol) isopropanol were stirred under an inert atmosphere and irradiated 4.5 hours with a 450 W Hanovia Hg lamp at a distance of 2-3 inches (5-7.6 cm). The acidic reaction mixture was then poured into 1.5 liters ice water. The organic layer was separated, washed twice with 50 ml water, dried with calcium sulfate, and distilled to give 50.5 gm ClCF 2 CF 2 CHClF, bp 54.5°-56° C. (55%). 1 H NMR (CDCl 3 ) ddd centered at 6.43 ppm. J H-C-F=47 Hz, J H-C-C-Fa=12 Hz, J H-C-C-Fb=2 Hz. Synthesis of 1,1-dichloro-1,2,2,3,3-pentafluoropropane (225cc). This compound may be prepared by reacting 2,2,3,3-tetrafluoro-1-propanol and p-toluenesulfonate chloride to form 2,2,3,3-tetrafluoropropyl-p-toluesulfonate. Next, the 2,2,3,3-tetrafluoropropyl-p-toluenesulfonate is reacted with potassium fluoride in N-methylpyrrolidone to form 1,1,2,2,3-pentafluoropropane. Then, the 1,1,2,2,3-pentafluoropropane is reacted with chlorine to form 1,1-dichloro-l,2,2,3,3-pentafluoropropane. Synthesis of 1,2-dichloro-1,1,3,3,3-pentafluoropropane (225d). This isomer is commercially available from P.C.R. Incorporated of Gainsville, Fla. Alternately, this compound may be prepared by adding equimolar amounts of 1,1,1,3,3-pentafluoropropane and chlorine gas to a borosilicate flask that has been purged of air. The flask is then irradiated with a mercury lamp. Upon completion of the irradiation, the contents of the flask are cooled. The resulting product will be 1,2-dichloro-1,1,3,3,3-pentafluoropropane. Synthesis of 1,3-dichloro-1,1,2,3,3-pentafluoropropane (225ea). This compound may be prepared by reacting trifluoroethylene with dichlorotrifluroromethane to produce 1,3-dichloro-1,1,2,3,3,-pentafluoropropane and 1,1-dichloro-1,2,3,3,3-pentafluoropropane. The 1,3-dichloro-1,1,2,3,3-pentafluoropropane is seperated from its isomers using fractional distillation and/or preparative gas chromatography. Synthesis of 1,1-dichloro-1,2,3,3,3-pentafluoropropane (225eb). This compound may be prepared by reacting trifluoroethylene with dichlorodifluoromethane to produce 1,3-dichloro-1,1,2,3,3-pentafluoropropane and 1,1-dichloro-1,2,3,3,3-pentafluoropropane. The 1,1-dichloro-1,2,3,3,3-pentafluoropropane is separated from its isomer using fractional distillation and/or preparative gas chromatography. Alternatively, 225eb may be prepared by a synthesis disclosed by O. Paleta et al., Bull. Soc. Chim. Fr., (6) 920-4 (1986). The 1,1-dichloro-1,2,3,3,3-pentafluoropropane can be separated from its two isomers using fractional distillation and/or preparative gas chromatography. It should be understood that the present compositions may include additional components which form new azeotrope-like compositions. Any such compositions are considered to be within the scope of the present invention as long as the compositions are constant-boiling or essentially constant-boiling and contain all of the essential components described herein. Inhibitors may be added to the present azeotrope-like compositions to inhibit decomposition of the compositions; react with undesirable decomposition products of the compositions; and/or prevent corrosion of metal surfaces. Any or all of the following classes of inhibitors may be employed in the invention: epoxy compounds such as propylene oxide; nitroalkanes such as nitromethane; ethers such as 1-4-dioxane; unsaturated compounds such as 1,4-butyne diol; acetals or ketals such as dipropoxy methane; ketones such as methyl ethyl ketone; alcohols such as tertiary amyl alcohol; esters such as triphenyl phosphite; and amines such as triethyl amine. Other suitable inhibitors will readily occur to those skilled in the art. Having described the invention in detail and by reference to preferred embodiments thereof, it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims. The present invention is more fully illustrated by the following non-limiting Examples. EXAMPLE 1 This example is directed to the preparation of the preferred dichloropentafluoropropane component of the invention 1,1-dichloro-2,2,3,3,3-pentafluoropropane (225 ca). Part A--Synthesis of 2,2,3,3,3-pentafluoropropyl-p-toluenesulfonate. To p-toluenesulfonate chloride (400.66g, 2.10 mol) in water at 25° C. was added 2,2,3,3,3-pentafluoro-1-propanol (300.8 g). The mixture was heated to 50° C. in a 5 liter, 3-neck separatory funnel-type reaction flask, under mechanical stirring. Sodium hydroxide (92.56 g, 2.31 mol) in 383 ml water (6M solution) was added dropwise to the reaction mixture via addition funnel over a period of 2.5 hours, keeping the temperature below 55° C. Upon completion of this addition, when the pH of the aqueous phase was approximately 6, the organic phase was drained from the flask while still warm, and allowed to cool to 25° C. The crude product was recrystallized from petroleum ether to afford 500.7 gm (1.65 mol, 82.3%) white needles of 2,2,3,3,3-pentafluoropropyl-p-toluenesulfonate (mp 47.0°-52.5° C.). 1 H NMR: 2.45 ppm (S,3H), 4.38 ppm (t,2H, J=12 Hz), 7.35 ppm (d,2H, J=6 Hz); 19 F NMR: +83.9 ppm (S,3F), +123.2 (t,2F,J=12 Hz), upfield from CFCl 3 . Part B--Synthesis of 1-chloro-2,2,3,3,3-pentafluoropropane. A 1 liter flask fitted with a thermometer, Vigreaux column and distillation receiving head was charged with 248.5 g (0.82 mol) 2,2,3,3,3-pentafluoropropyl-p-toluenesulfonate (produced in Part A above), 375 ml N-methylpyrrolidone, and 46.7 g (1.1 mol) lithium chloride. The mixture was then heated with stirring to 140° C. at which point, product began to distill over. Stirring and heating were continued until a pot temperature of 198° C. had been reached at which point, there was no further distillate being collected. The crude product was re-distilled to give 107.2g (78%) of product (bp 27.5°-28° C.). 1 H NMR: 3.81 ppm (t,J=13.5 Hz) 19 F NMR: 83.5 and 119.8 ppm upfield from CFCl 3 . Part C--Synthesis of 1,1-dichloro-2,2,3,3,3-pentafluoropropane. Chlorine (289 ml/min) and 1-chloro-2,2,3,3,3-pentafluoro-propane (produced in Part B above), (1.72 g/min) were fed simultaneously into a 1 inch (2.54 cm)×2 inches (5.08 cm) monel reactor at 300° C. The process was repeated until 184 g crude product had collected in the cold traps exiting the reactor. After washing the crude product with 6M sodium hydroxide and drying with sodium sulfate, it was distilled to give 69.2 g starting material and 46.8 g 1,1-dichloro-2,2,3,3,3-pentafluoropropane (bp 48°-50.5° C.). 1 H NMR: 5.9 (t, J=7.5 H) ppm; 19 F NMR: 79.4 (3F) and 119.8 (2F) ppm upfield from CFCl 3 . EXAMPLE 2 The compositional range over which 225ca and cyclohexane exhibit constant boiling behavior was determined. This was accomplished by charging measured quantities of 225ca into an ebulliometer. The ebulliometer consisted of a heated sump in which the HCFC-225ca was brought to a boil. The upper part of the ebulliometer connected to the sump was cooled thereby acting as a condenser for the boiling vapors, allowing the system to operate at total reflux. After bringing the HCFC-225ca to a boil at atmospheric pressure, measured amounts of cyclohexane were titrated into the ebulliometer. The change in boiling point was measured with a platinum resistance thermometer. The results indicate that compositions of 225ca/cyclohexane ranging from 94-99.99/0.01-6 weight percent respectively would exhibit constant boiling behavior at 50.6° C. ± about 0.5° C. at 748 mm Hg. EXAMPLES 3-12 The azeotropic properties of the dichloropentafluoropropane isomers and C 6 hydrocarbons listed in Table I were studied. This was accomplished by charging measured quantities of dichloropentafluoropropane (from column A) into an ebulliometer. The dichloropentafluoropropane component was brought to a boil. The upper part of the ebulliometer connected to the sump was cooled thereby acting as a condenser for the boiling vapors, allowing the system to operate at total reflux. After bringing the dichloropentafluoropropane component to a boil at atmospheric pressure, measured amounts of C 6 hydrocarbon (column B) were titrated into the ebulliometer. The change in boiling point was measured with a platinum resistance thermometer. The range over which the various mixtures exhibited constant boiling behavior is reported in Table I. TABLE I__________________________________________________________________________A. B. Constant BoilingDichloropenta- C.sub.6 Composition (wt %) Constant BoilingEx. fluoropropane Hydrocarbon A. B. Temp.** (°C.)__________________________________________________________________________3 225ca n-hexane 94.0-99.5 0.5-6.0 50.5 ± 0.24 225ca 2-methylpentane 83.0-94.0 6.0-17.0 49.8 ± 0.55 225ca 3-methylpentane 85.5-96.5 5.5-14.5 50.0 ± 0.56 225ca methylcyclo- 93.0-99.99 0.01-7.0 50.5 ± 0.3 pentane7 225ca commercial 77.0-92.5 7.5-23.0 48.5 ± 1.5 isohexane*8 225cb n-hexane 76.5-88.5 11.5-23.5 54.9 ± 0.49 225cb 2-methylpentane 68.0-85.0 13.0-32.0 52.7 ± 0.410 225cb 3-methylpentane 71.0-90.0 10.0-29.0 53.4 ± 0.411 225cb methylcyclo- 83.5-96.5 3.5-16.5 54.8 ± 0.4 pentane12 225cb cyclohexane 90.0-99.0 1.0-10.0 55.9 ± 0.2__________________________________________________________________________ *Commercial isohexane sold by Phillips 66 was used in this experiment. **The boiling point determinations for Examples 3-12 were made at the following barometric pressure (mm Hg): 746, 751, 744, 744, 737, 756, 750, 744, 746 and 761 respectively. EXAMPLES 13-21 The azeotropic properties of the dichloropentafluoropropane components listed in Table II with cyclohexane are studied by repeating the experiment outlined in Examples 3-12 above. In each case a minimum in the boiling point versus composition curve occurs indicating that a constant boiling composition forms between the dichloropentafluoropropane component and cyclohexane. TABLE II______________________________________Dichloropentafluoropropane Component______________________________________2,2-dichloro-1,1,1,3,3-pentafluoropropane (225a)1,2-dichloro-1,2,3,3,3-pentafluoropropane (225ba)1,2-dichloro-1,1,2,3,3-pentafluoropropane (225bb)1,1-dichloro-1,2,2,3,3-pentafluoropropane (225cc)1,2-dichloro-1,1,3,3,3-pentafluoropropane (225d)1,3-dichloro-1,1,2,3,3-pentafluoropropane (225ea)1,1-dichloro-1,2,3,3,3-pentafluoropropane (225eb)1,1-dichloro-2,2,3 3,3-pentafluoropropane/1,3-dichloro-1,1,2,2,3-pentafluoropropane (mixture of 225ca/cb)1,1-dichloro-1,2,2,3,3,3-pentafluoropropane/1,3-dichloro-1,1,2,2,3-pentafluoropropane (mixture of (25eb/cb)______________________________________ EXAMPLES 22-30 The azeotropic properties of the dichloropentafluoropropane components listed in Table II with n-hexane are studied by repeating the experiment outlined in Examples 3-12 above. In each case a minimum in the boiling point versus composition curve occurs indicating that a constant boiling composition forms between the dichloropentafluoropropane component and n-hexane. EXAMPLES 31-39 The azeotropic properties of the dichloropentafluoropropane components listed in Table II with 2-methylpentane are studied by repeating the experiment outlined in Examples 3-12 above. In each case a minimum in the boiling point versus composition curve occurs indicating that a constant boiling composition forms between the dichloropentafluoropropane component and 2-methylpentane. EXAMPLES 40-48 The azeotropic properties of the dichloropentafluoropropane components listed in Table II with 3-methylpentane are studied by repeating the experiment outlined in Examples 3-12 above. In each case a minimum in the boiling point versus composition curve occurs indicating that a constant boiling composition forms between the dichloropentafluoropropane component and 3-methylpentane. EXAMPLE 49-57 The azeotropic properties of the dichloropentafluoropropane components listed in Table II with methylcyclopentane are studied by repeating the experiment outlined in Examples 3-12 above. In each case a minimum in the boiling point versus composition curve occurs indicating that a constant boiling composition forms between the dichloropentafluoropropane component and methylcyclopentane. EXAMPLES 58-68 The azeotropic properties of the dichloropentafluoropropane components listed in Table II below with commercial isohexane grade 1 are studied by repeating the experiment outlined in Examples 3-12 above. In each case a minimum in the boiling point versus composition curve occurs indicating that a constant boiling composition forms between the dichloropentafluoropropane component and commercial isohexane grade 1. TABLE III______________________________________Dichloropentafluoropropane Component______________________________________2,2-dichloro-1,1,1,3,3-pentafluoropropane (225a)1,2-dichloro-1,2,3,3,3-pentafluoropropane (225ba)1,2-dichloro-1,1,2,3,3-pentafluoropropane (225bb)1,1-dichloro-2,2,3,3,3-pentafluoropropane (225ca)1,3-dichloro-1,1,2,2,3-pentafluoropropane (225cb)1,1-dichloro-1,2,2,3,3-pentafluoropropane (225cc)1,2-dichloro-1,1,3,3,3-pentafluoropropane (225d)1,3-dichloro-1,1,2,3,3-pentafluoropropane (225ea)1,1-dichloro-1,2,3,3,3-pentafluoropropane (225eb)1,1-dichloro-2,2,3,3,3-pentafluoropropane/1,3-dichloro-1,1,2,2,3-pentafluoropropane (mixture of (225ca/cb)1,1-dichloro-1,2,2,3,3,3-pentafluoropropane/1,3-dichloro-1,1,2,2,3-pentafluoropropane (mixture of (25eb/cb)______________________________________ EXAMPLES 69-79 The azeotropic properties of the dichloropentafluoropropane components listed in Table III with commercial isohexane grade 2 are studied by repeating the experiment outlined in Examples 3-12 above. In each case a minimum in the boiling point versus composition curve occurs indicating that a constant boiling composition forms between the dichloropentafluoropropane component and commercial isohexane grade 2. EXAMPLES 80-90 The azeotropic properties of the dichloropentafluoropropane components listed in Table III with 2,2-dimethylbutane are studied by repeating the experiment outlined in Examples 3-12 above. In each case a minimum in the boiling point versus composition curve occurs indicating that a constant boiling composition forms between the dichloropentafluoropropane component and 2,2-dimethylbutane. EXAMPLES 91-101 The azeotropic properties of the dichloropentafluoropropane components listed in Table III with 2,3-dimethylbutane are studied by repeating the experiment outlined in Examples 3-12 above. In each case a minimum in the boiling point versus composition curve occurs indicating that a constant boiling composition forms between the dichloropentafluoropropane component and 2,3-dimethylbutane.

Stable azeotrope-like compositions consisting essentially of dichloropentafluoropropane and a hydrocarbon containing six carbon atoms which are useful in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

[0001] The invention relates to local contextual communications or telecommunications, i.e. on site and as a function of the context. [0002] Proposals of this kind have already been made particularly in patent specification WO 01/89189 A2 by the same applicant. The context is defined using “mobile stations” which can be installed as required at different locations in a given place. The cooperation of these stations with posts such as portable telephones (or mobile telephones) makes it possible to recognise the context and hence to deliver a message as a result, from a contextual service provider. We will return to this in more detail hereinafter. [0003] It is desirable to find a solution which is as universal as possible while avoiding having the user being inundated by unwanted messages or unsolicited services, as will be seen. [0004] The present invention sets out to improve this situation. It proposes a local communications device of the type having a station which has a mode of communication with mobile terminals and a controller capable of sending a message intended for one or more mobile terminals. The device according to the invention further comprises a beacon capable of interacting with at least one passive portable object in order to obtain at least one code word from such a portable object. According to the invention, the controller is designed to interact with the beacon in order to memorise the code word obtained, at least temporarily, and then subsequent to this interaction, to implement a decision mechanism relating to the spontaneous sending of a message, in which the decision to send a message, its contents and/or its destination address depend at least partially on the code word stored. [0005] Further features and advantages of the invention will become apparent from a study of the detailed description that follows and the attached drawings, wherein: [0006] FIG. 1A is a diagram illustrating one embodiment of the device according to the invention, [0007] FIG. 1B is a diagram illustrating a detail of the device in FIG. 1A according to an alternative embodiment, [0008] FIG. 2A is a diagram illustrating a tag for the device in FIG. 1A according to one embodiment of the invention, [0009] FIG. 2B is a diagram illustrating a tag for the device in FIG. 1A according to a different embodiment of the invention, [0010] FIG. 3 is a flow chart illustrating the operation of the device in FIG. 1A according to one embodiment of the invention, [0011] FIGS. 4A to 4D are diagrams showing different arrangements of the device in FIG. 1A , [0012] FIG. 5 is a diagram illustrating an embodiment of a beacon for the device according to the invention in a particular application, [0013] FIG. 6 is a diagram illustrating an embodiment of a beacon for the device according to the invention in another particular application, [0014] FIG. 7 is a flow chart illustrating the operation of the device according to the invention in the particular applications in FIGS. 5 and 6 . [0015] The drawings contain elements of a specific type. They may therefore serve not only to assist with the understanding of the present invention but may also contribute to the definition thereof, where appropriate. DESCRIPTION [0016] The invention relates to a “contextual service” which ensures the contextual provision of information on a mobile terminal. By contextual provision is meant the ability to provide selectively, without further requests by the user other than the choice of information, information relating to the environment observed by the user: objects or persons in the vicinity, the location/building/room where the user is located, in particular. The information to be supplied to the user may be of various types: a text message, image, sound, video, optionally by streaming, a composite document such as a web page or a hyperlink (pointer) towards a document (Web or Wap, for example), although this list is not restrictive. In the phrase “contextual provision”, the notion of “context” represents the local physical ambience as oppose to the context procured by the mobile terminal itself on account of its communication functions. In particular, the different communication possibilities provided in general terms by the mobile terminal itself are not regarded as “contextual information”. [0017] A context may be defined by a number of general approaches. [0018] A first approach implies previous identification of the location. It consists in supplying the contextual information after having determined the position of the user carrying the mobile terminal. A location infrastructure such as GPS will do this, but this method is fairly onerous and not universal as few mobile terminals are equipped with this location function. It is also known that the communications network supplied to the mobile terminal may provide an approximate location for the user with his terminal by trying out triangulations according to the positions of the base stations that “see” the mobile terminal. However, the position of the user can only be determined with a degree of approximation that varies widely according to the place: in effect, as the complete opposite to GPS, for example, the infrastructure is not specifically designed for positioning because the arrangement of the base stations is determined essentially with the aim of ensuring good connectivity for the network users. This other method which is again not universal is furthermore inadequate where precise and reliable positioning is required. [0019] A different approach which may be termed “physical” is described in the patent specification WO 01/89189 A2, mentioned previously, by the same applicant. Here, a local communications device is provided comprising at least one station having means for communicating with mobile terminals. According to this approach, an attempt is made to define “zones” associated with each type of contextual information directly by a particular geometric arrangement of physical objections. In WO 01/89189 A2, these objections are termed “mobile stations”, in that they can be placed at any desired location and moved again if necessary. The “zones” can thus be made variable to the necessary degree for modifying the physical arrangement of the objects (“mobile stations”) which define them in order to modify the perimeters associated with the stations. A “contextual service” can then send a message (more generally a modulated contextual service) to one or more users. This is controlled by the exchange of information between the station or stations and the or each mobile terminal. This implicitly involves the use of a controller capable of sending the message corresponding to the contextual service. [0020] The station or stations may be equipped with a short range communications system such as Bluetooth which may be supplemented by access to an extended communications network such as mobile telephony. [0021] The present invention is a descendent of WO 01/89189 A2. In the context of a “physical approach” there is therefore on the one hand an infrastructure comprising the stations and a service provided on demand by telecommunications, and on the other hand pairs of mobile terminals/users. [0022] The applicant has noted that two major subclasses can thus be differentiated. [0023] The first subclass is referred to here as the pull approach. In this case the context is determined at the level of the mobile terminal/user pair. The mobile terminal collects a set C of information (attributes) from the surrounding stations. The mobile terminal then contacts the service provider itself, theoretically automatically, specifying the set of attributes C. This allows the service to be adapted/modulated and be delivered in return to the mobile terminal. In this “pull” approach, access to the service is initiated by the mobile terminal/user pair. [0024] The “pull” subclass requires that a material component and/or specific software dedicated to acquiring the context and subsequently accessing the service be implanted in the mobile terminal. This component can be configured by the user in order to give access only to certain types of contextual information or possibly none. This means that this approach is not universal, owing to the need to install a specific component and also for the user to configure it, especially in order to specify the filtering of the information which is to be collected, a procedure which is not necessarily understandable to everyone. [0025] The second subclass is termed here the “push” approach. In this case the mobile terminal/user pair is detected by the infrastructure and then contacted directly by the latter which thus initiates the service. The drawback of this latter method (push) is that it does not take account of the wishes of the user (who has the mobile terminal) as the service can directly reach all the terminals which are “within range”. The user may thus find himself repeatedly contacted by unwanted contextual messages or, at the very least, by interrogations of his mobile terminal, asking for his consent to receive contextual messages. This is the case particularly with the Bluetooth push, which involves contacting the user every time he enters the zone within range of the service. This is similar to the nuisance felt, moreover as a result of unwanted messages known as “spam”. [0026] It is also possible to look at the possibility of using a global communications infrastructure (of the SMS platform type). Architecture [0027] The architecture of the contextual local communication device 1 according to the invention will now be described with reference to FIG. 1A . [0028] The communications device 1 according to the invention comprises a contextual service control platform 3 (or controller) operating according to the push approach described above. The control platform 3 is associated with a contextual service zone 5 . By this is meant that the control platform 3 is arranged so as to deliver at least one contextual service virtually anywhere in the service zone 5 . The service zone 5 is determined as a function of at least one physical element of interest 7 linked to at least one service to be delivered in the service zone 5 . The form and nature of this physical element 7 and the nature of the service to be provided may be interdependent. [0029] As a non-restrictive example, the physical element 7 may be a public notice board and the service zone 5 may be determined so that messages on this board are visible from anywhere in the service zone 5 . [0030] The control platform 3 is connected to at least one short range wireless communications interface 9 capable of setting up such a communication with mating communication means present in the service zone 5 . In particular, the communication interface 9 makes it possible to establish a communication with at least one mobile terminal 11 provided with compatible short range wireless communication means 13 and located within the service zone 5 . This communication allows the mobile terminal 11 to receive a message transmitted by the control platform 3 . [0031] The mobile terminal 11 may be in the form of a mobile telephone, a portable computer, a personal digital assistant, an earpiece of the Bluetooth type, or the like. [0032] More and more mobile telephones and personal digital assistants designed nowadays incorporate Bluetooth communication means in series: the control platform 3 therefore preferably comprises a communications interface 9 that conforms to this standard. [0033] Other short range wireless communication technologies such as WIFI (as defined in IEEE 802.11b/g), ZigBee or the like may be used. [0034] In an advantageous embodiment not shown here, the control platform 3 comprises a plurality of short range wireless communications interfaces 9 of different technologies. Thus, communications using different technologies may be established within the service zone 5 , thus increasing the compatibility of the device according to the invention with commercial mobile terminals 11 . This also reduces the respective costs of each communications interface 9 . [0035] Preferably, the control platform 3 comprises a plurality of communications interfaces 9 of the same technology in order to reduce the respective loads for each interface still further. Thus, better availability and a more reactive service are obtained as the connections are distributed over several interfaces. This is particularly noticeable in the case of a number of Bluetooth interfaces. [0036] The control platform 3 is linked to a radio frequency tag detecting network 15 arranged so as to detect the entry, exit and/or presence of a tag 17 of this kind within the service zone 5 . [0037] The tags 17 here may be of the type known as RFID. More generally, what is referred to as “radio frequency tag” in this description is a small portable object, passive or quasi-passive, which permanently stores a collection of bits and can be interrogated by short range radio communication. Throughout the present description this collection of bits will be referred to as the memory. Other types of tag may be used, for example NFC tags (from the English term Near Field Computing). [0038] The detection network 15 comprises at least one manager 19 and an antenna 21 connected thereto. The antenna 21 is capable of reading the data contained in the memory of a radio frequency tag 17 within its range. [0039] In one embodiment, the detection network 15 comprises a single antenna 21 connected to the manager 19 : the presence of the tag 17 within range of the antenna can thus be detected. It is then possible to detect the presence of the tag 17 at a particular point in the service zone 5 . The data contained in the memory of the tag 17 can only be read at this particular point in the service zone 5 . [0040] In another embodiment, the detection network 15 comprises a plurality of antennas 21 connected to the manager 19 and distributed so as to cover an area that is greater than the range of a single antenna 21 . In particular, the antennas 21 may be distributed so that a tag 17 can be read anywhere in the service zone 5 or be distributed along the periphery of the service zone 5 . [0041] The detection network 15 may in the case of a plurality of antennas comprise a plurality of managers 19 , particularly when the maximum number of antennas that can be connected to the manager 19 is reached. [0042] The manager 19 may comprise, for example, an RI-CTL-MB2A controller of series S2000 manufactured by Texas Instruments and RF-MOD-TX8A multiplexers manufactured by the same company. [0043] In some configurations ( FIG. 1B ), the service zone 5 is accessible only through obligatory identified pass-through points. In this case an entry/exit detector connected to the manager is advantageously provided at each of these pass-through points. A detector of this kind comprises, for example, two rows of antennas 21 A and 21 B arranged at said pass-through point, parallel to one another and transversely with respect to the direction of movement. Thus the direction of movement of a tag 17 can be detected: when the row 21 A detects a tag 17 in front of the row 21 B the direction of movement is from antenna 21 A towards antenna 21 B, and vice versa. [0044] This embodiment avoids having to distribute antennas 21 throughout the service zone 5 . [0045] Advantageously, so called “flexible” antennas are used which can follow the contour of a support, e.g. flexible antennas on plastic film of the CIPAM CIP_ANT-LF type. [0046] The control platform further comprises a computer 23 capable of controlling the provision of services by the “push” approach. [0047] Optionally, the control platform 3 comprises local storage means for contents to be delivered (not shown). These means may take the form of NAS servers (from the English term Network Area Storage). [0048] The control platform 3 further comprises an access interface 25 to a global communications network 26 of the wired or wireless type, such as GSM, GPRS, EDGE, UMTS, IP or the like. [0049] This communications interface 25 allows the control platform 3 , on the one hand, to access remote data processing means which are suitable for carrying out data processing for at least some of the services to be provided in the service zone 5 or for material resources which are away from the service zone 5 . [0050] On the other hand, the interface 25 makes it possible to establish communication with mobile terminals 11 which have related global communications means 27 , i.e. of the cellular network type, for example, GSM, GPRS, EDGE, UMTS or the like. This makes it possible in particular to establish communication with a mobile terminal 11 of the standard portable telephone type. [0051] According to the invention the tag 17 is arranged on an object carried by the user of a mobile terminal. This portable user object may advantageously take the form of a card, for example resembling a credit card. The portable object may also take the form of a key ring. Finally, the tag may be self adhesive so that it can be placed on any substrate at the user's discretion. In particular, the tag may also be integrated in common objects carried by the user, for example clothes (shoes, pullover, etc.). [0052] The tag 17 is advantageously of the type known as a passive tag, i.e. the tag 17 has no autonomous energy or processing capacity. It is nevertheless capable of responding to an interrogation request by sending a message containing the data stored in its memory. The energy needed for this activity is drawn from the induction current of the signal from the interrogation apparatus, in this case the antennas 21 . This design means that the system is free from energy constraints and the weight that this implies. [0053] It will be understood, however, that active tags, i.e. those which have their own energy source, could be used provided that they operate in passive mode, i.e. they are restricted to responding to an interrogation signal. [0054] By way of example, it is possible to use tags known as TITIS RI-TRP-W4FF manufactured by Texas Instruments. [0055] FIG. 2A illustrates the contents of the memory of a tag 17 A adapted to interact with the device according to the invention, in a first embodiment of the invention. [0056] The memory of the tag 17 A stores communication address data ComAdrDat relating to the mobile terminal. The data ComAdrDat comprise a contact address for the mobile terminal 11 by the contextual service, for example, a material address of the communications interface 13 , for example the material address of a Bluetooth interface, or a cell phone number. [0057] The communication address data ComAdrDat may constitute a user identifier, for example at the level of the control platform 3 . In some cases, the communication address data ComAdrDat may be supplemented or replaced by a user identifier of this kind in the tag 17 A itself. [0058] Optionally, the memory of the tag 17 A stores general service data ServGenDat relating to at least one service likely to interest the user. The data ServGenDat comprise in particular an identifier of the service that interests the user. [0059] Moreover, the memory of the tag 17 A may optionally store specific service data ServSpecDat that characterise a particular service or the user in relation to this particular service (profile, preferences). These specific data may constitute attributes relating to a particular service. [0060] Preferably, the data ComAdrDat, ServGenDat and ServSpecDat are stored in the same tag, reserving bit areas for the different data. This allows in particular simplified reading of the different data, as a single tag must be detected. The data ComAdrDat, ServGenDat and ServSpecDat thus form one and the same code word. [0061] The data ComAdrDat, ServGenDat and ServSpecDat may nevertheless be stored in different tags, particularly when the capacity of the memory of a single tag 17 is not sufficient. The data ServGenDat and ServSpecDat thus form several code words (or a set of codes). [0062] When a number of tags are provided, these may be applied to the same portable object: for example, an object specific to a particular contextual service, the memories of the tags storing data relating to this particular service. However, the tags may also be linked to separate portable objects: for example the data ComAdrDat may be stored on a tag on a first portable object, while the data ServGenDat and ServSpecDat relating to different services may be distributed over second portable objects, each portable object being assigned to a particular service. [0063] It will be understood that multiplying the tags offers the possibility for the user to manage the properties of the different services: in the case of portable objects assigned to a particular service, the user can choose to take one object with him rather than another, so as to benefit from a particular service and do without another, in the case of different portable objects wherein the tag or tags store different data ServSpecDat but relating to the same service defined by data ServGenDat, the combination of the portable objects carried by the user defines the attributes of the contextual service to be provided. [0066] Alternatively or additionally, at least some of the tags may be selectively activated and deactivated, for example by physical intervention on the tag, or by reversibly placing a radiation-proof mask over the tag. [0067] In particular, we have described how the combination of different portable objects might define the contextual service or services provided, but it will be appreciated that the different tags used in these cases may be provided on the same portable object and made capable of activation/deactivation by the processes described above. [0068] The tag 17 A contains, as a minimum, the communication address data ComAdrDat. This does not mean that other additional information-carrying tags may not be provided which do not contain a communication address. [0069] In another embodiment of the invention shown in FIG. 2B , the memory of a tag 17 B stores only database address data DBAdrDat. These data DBAdrDat comprise an address for registration of a database, stored for example on the platform 3 . This registration comprises communication address data ComAdrDat and optionally general service data ServGenDat and specific service data ServSpecDat, analogously to the data in FIG. 2A . [0070] The contents of the memory of a tag 17 may be encrypted, for example using the algorithm RSA or the algorithm 3DES to ensure data confidentially. In this case, the control platform 3 advantageously maintains an encryption key, of public or private nature, enabling data encryption. [0071] According to the invention, the portable object provided with a tag 17 is intended to be carried by the user of the mobile terminal 11 . The tag 17 and the mobile terminal 11 are associated by the data ComAdrDat (tag of type 17 A) or by data relating to the terminal 11 stored in a registration of a database designated by the data DBAdrDat (tag of type 17 B). The tag 17 and the mobile terminal 11 thus form a pair. Operation [0072] The operation of the device according to the invention will now be described with reference to the flow chart in FIG. 3 . [0073] A user carries a pair consisting of a radiofrequency tag 17 and a mobile terminal 11 . The user enters the service zone 5 . [0074] In step 300 , an antenna 21 detects the presence of the tag 17 within its range. [0075] In step 302 , all the data in the memory of the tag 17 are read by the antenna 21 and then sent to the control platform 3 . In particular, the control platform 3 receives the communication address data ComAdrDat, the general service data ServGenDat and, if applicable, the specific service data ServSpecDat. [0076] In step 304 , the control platform 3 compares the general service data ServGenDat identifying at least one service desired by the user with the services available on this control platform 3 . If the service identified is not available on the control platform 3 , the process is abandoned (step 306 ). [0077] Otherwise, in step 308 , the control platform 3 drafts a content specific to the contextual service identified. If appropriate, this draft takes into account the specific service data ServSpecDat. In a non-restrictive manner, the content drafted may take the form of a text message, a sound message, an internet address, optionally streamed, or an application that can be run on the mobile terminal 11 . [0078] In step 310 the control platform 3 sends a message that incorporates the content drafted in step 308 to the address defined by the communication address data ComAdrDat. [0079] In step 312 , the mobile terminal 11 determines the appropriate action for the message received as a function of the type of message (actual message or application). For example: the message may be a sound message played back by the conventional sound reproduction means of the mobile terminal 11 , the message may be an SMS text message relayed by the conventional means of the mobile terminal 11 , the message may contain a link to a contents address (e.g. an internet address or URL) and in the particular case of the message being a pointer to a service or a Web or Wap page, the mobile terminal 11 may launch a Web or Wap navigator, the message may take the form of an application such as a Java application, for example, suitable for running directly on the mobile terminal 11 when the latter supports this technology (if not, a link to a Web or Wap service may be provided if necessary). [0084] Other forms of message may be envisaged. The message received may comprise a link to an application to be downloaded to the mobile terminal 11 . This application may in turn implement a service. Moreover, this service may thus be contextual and interact by the pull approach. In other words, the push approach proposed here may serve to trigger a contextual service operating by the pull approach. One useful embodiment may consist in delivering an initial application (“bootstrap”) by the push approach. This application then launches the reading of a radiofrequency tag, this time in the mobile terminal 11 , provided with a suitable reader. The contents can then be obtained by the pull approach by a Bluetooth, Wifi, GPRS or similar wireless communications means, from local and/or remote servers. This approach reduces the energy consumption linked with a permanent RFID reader on the mobile terminal: this reading is in fact initiated in contextual manner by the application obtained by the push approach in appropriate circumstances. [0085] In the particular embodiment of a tag 17 of the type in FIG. 2B , the tag 17 stores only the data DBAdrDat, in step 302 , in the form of a link to a database linked to the control platform 3 , said database holding information that allows the mobile terminal 11 to be contacted. Specific service data ServSpecDat relating to the service to be delivered and peculiar to the carrier of the tag 17 , or general service data ServGenDat, are held in this database. These data are also used to draft the contents of step 308 . The implementation of steps 310 and 312 is thus identical to the embodiment in FIG. 2A . [0086] In an alternative method, the communication address data ComAdrDat comprise a call number for the mobile terminal 11 via the global communications network 26 . Typically, this may be a telephone number. [0087] To deliver the message, the control platform 3 can then contact a remote control platform specific to the global network 26 . Advantages [0088] The communication device according to the invention has numerous advantages. [0089] Thus, the risk of the user receiving unsolicited messages is reduced considerably as only the users carrying a tag can give permission to identify the desired service in order to be contacted. Moreover, the communication address of the mobile terminal 11 has to be known in order to contact the user, and this reading may take place locally. [0090] The identification of the desired service may take place in particular on the basis of the following basic information: directly by a service identifier drawn from the tag, as a function of “user preferences” that can be deduced directly or indirectly from information carried by the tag, as a function of profile data which can be taken from a history of previous “contacts” with this user, and/or other tags carried or information supplied by the user. [0094] The same basic information may be used not only to take the decision to send a message, but also to draft or modify its contents. [0095] When the short-range wireless communications technology used is Bluetooth, the Bluetooth communication address stored in the memory of the tag is immediately known, thus dispensing with the conventional Bluetooth address discovery phase. This advantage may also be obtained with other communication technologies wherein the discovery time of the communication interfaces is considerable. [0096] More generally, the device according to the invention makes it possible to dispense with the discovery mode relative to the short-range wireless communication interface. In fact, this mode is particularly vulnerable to “spam” as it regularly distributes communication address data ComAdrDat or the like. [0097] In the variant in which the communication address data, for example ComAdrDat, comprise a telephone number (or other number of a global telephone service), the device according to the invention offers universal communication possibilities, in that all mobile telephone equipment is capable of receiving a message from the device according to the invention while remaining highly secure against unsolicited messages for the reasons stated hereinbefore. [0098] The devices of the prior art which have a tag reader on the mobile terminal 11 have a drawback: software for reading the contents of the radiofrequency tag has to be activated by the user. In fact, this is impractical and ineffective, as the user has a tendency to forget to activate the software. Alternatively, this software may be constantly active, but this then implies a permanent energy expenditure which is unacceptable for mobile terminals, which are known to have a limited autonomous electricity supply. The device according to the invention overcomes these drawbacks: on the one hand, there is no need for the user to activate detection software, and on the other hand the elements that consume the most energy are fixed and can therefore be connected to a major energy source, for example the mains electricity supply network. Arrangements [0099] The communication device 1 according to the invention may be arranged in various ways. [0100] In the configuration in FIG. 4A the physical element of interest 7 is arranged inside a closed area 29 accessible by an obligatory pass-through point at which antennas 21 A and 21 B are provided. The Bluetooth interface 9 is arranged outside the area 29 and covers virtually all of it. The zone covered by the Bluetooth interface 9 defines the contextual service zone 5 . The antennas 21 read the radiofrequency tag 17 carried by a user entering the area 29 . The user can obtain the delivery of a contextual service anywhere within the area 29 but also outside it. It will be understood that the Bluetooth interface 29 could be provided inside the area 29 and its range adapted to cover substantially only the zone delimited by the enclosed area 29 . [0101] In a particular case (not shown), the antennas 21 A and 21 B are arranged to form an entry/exit detector, such as the detector described hereinbefore. The control platform 3 can then be programmed so as to abandon the process of delivering the contextual service when the antennas 21 detect that the user is leaving the area 29 . [0102] For example, the configuration of FIG. 4A may be used in a store: the communication address data ComAdrDat are read at the entrance to the store by the antennas 21 A and 21 B and the Bluetooth interface 9 sends commercial information inside the store. [0103] In FIG. 4B , two physical elements of interest 7 A and 7 B are shown. Close to each of these elements 7 A and 7 B is provided an antenna 21 connected to the manager 19 . [0104] The elements 7 A, 7 B and the antennas 21 are arranged within the coverage zone of the short-range wireless communication interface 9 . This coverage zone delimits the service zone 5 . The tag 17 can be read when the user approaches one of the physical elements of interest 7 A or 7 B. The user can receive the contextual service anywhere in the zone 5 . [0105] The arrangement according to FIG. 4B can be used in an airport, for example. The elements 7 A and 7 B take the form of registration desks, possibly for different airlines. The communication address data ComAdrDat of the tag 17 are read at these desks using antennas 21 . Information relating to a particular flight may be contained within the specific service data ServSpecDat of the same tag 17 or a different tag. Advantageously, the tag or tags 17 are then placed on the user's ticket. Even after he has left the desk, the user can be informed that his flight is about to embark, by receiving a message through the Bluetooth interface 9 . [0106] In FIG. 4C , two physical elements of interest 7 A and 7 B are arranged inside an enclosure 29 accessible by a single obligatory pass-through point at which two antennas 21 are provided. Close to each of the elements of interest 7 A, 7 B there is provided a short-range wireless communication interface 9 A or 9 B, respectively. Thus, a geographical zone surrounding the elements of interest 7 A or 7 B is covered by the short-range wireless communication interface 9 A or 9 B, respectively. Two service zones 5 A and 5 B are thus defined. The reading of the radiofrequency tag 17 carried by a user is carried out by the antennas 21 as he enters the area 29 . [0107] The arrangement in FIG. 4C can also be used in an airport. The communication address data ComAdrDat and the data relating to the user's flight can be read at the entrance to the airport. When the user approaches the embarkation point allocated to his airline (for example the element 7 A) he receives time alerts, possibly at regular intervals, as to the final registration times. [0108] In FIG. 4D , the physical element of interest 7 , the antenna 21 and the short-range wireless communication interface 9 are arranged close to one another. The short-range wireless communication interface 9 defines a contextual service zone 5 centred on the physical element of interest 7 . [0109] The arrangement in FIG. 4D may be used externally in a street furniture element such as a town plan, for example. The communication address data ComAdrDat are read at said street furniture element (element of interest 7 ) by the antenna 21 and the location data for example are received through the Bluetooth interface 9 on the mobile terminal. All this takes place in a localised geographical zone. Examples of Use [0110] A non-restrictive example of the use of the device according to the invention will now be described. [0111] A user contacts or is contacted by a contextual service provider who offers to provide for him, on his mobile telephone, targeted information relating to his particular interests. [0112] The service provider enters in the memory of the tag 17 a first information item relating to the technology to be used to deliver the service, such as Bluetooth or GSM/GPRS. Depending on the particular case, the user's telephone number or the material address of the Bluetooth interface 13 of his portable telephone 11 is recorded in the memory of the tag 17 . If appropriate, this Bluetooth address may be detected, for example if a Bluetooth discovery mode of the telephone, or the like, is activated. [0113] The service provider also stores, as general service data ServGenDat, information identifying the advertising service targeted, and, as specific service data ServSpecDat, information identifying one or more spheres of interest of the user. [0114] The provider gives a card bearing the tag 17 thus programmed to the user. [0115] If the user goes to a store in which the device according to the invention is installed, the radiofrequency tag 17 that he carries is read, for example by antennas 21 arranged at the entrance to the store. After processing of the information collected by the platform 3 , the user receives a message on his phone 11 listing the promotions on items connected with the sphere(s) of interest stored. [0116] In a similar example, the user may wear a pullover on which the manufacturer has provided a tag 17 containing specific data relating to the brand of the pullover. When the user is also carrying a tag 17 containing communication address data ComAdrDat, he can receive on his mobile terminal 11 a list of promotions relating to the brand of pullover that he is wearing. Nature of the Message Sent [0117] The content pushed to the terminal may be a message of static content (such as a media text, a piece of music, an image or a video), in the sense that it is not a program. It may also be a active content in the sense of a program to be activated immediately (in the moment following the action needed to access the content). [0118] Typically, it would be a Java program, “packaged” in a JAR-type archive containing not only the program (executable code) but also the appropriate data (such as information which is geo-dependent or dependent on the context). [0119] The JAR (or equivalent) is hence an autonomous package (in the sense of self-sufficient) intended to be executed in the immediate vicinity of the physical object that delivers it. A package of this kind is referred to here as a “Griplet” (from the English word grip), as it is a small software application to be “gripped” by a movement of the hand and used immediately. The package could be deleted by the user when he has no further need for it, or replaced by another Griplet loaded from another physical object. Thus it is to some extent a “disposable” software application. [0120] A number of griplets may be associated with the same service, each version corresponding to a different set of parameters. A griplet may also be generated dynamically in relation to the user's choice. [0121] Numerous modes of distributing griplets and more generally applications to be pushed may be envisaged. [0122] In a first mode, all the resources needed for the operation of the application are assembled in an archive, for example an archive of JAR format where the JAVA programming language is concerned. This archive may also be signed, so that the mobile terminal receiving it can verify the origin of the contents by means of a certificate. [0123] In a second mode, the mobile terminal has an initial executable program which may, if applicable, be received by push. Complementary elements may be received subsequently, capable of interacting with the initial executable program. These elements may be received by push. These complementary elements may take the form of: a content that may be termed “static”, i.e. data of the text, image, sound or similar type, or composite documents, executable program modules that complete the functions of the initial program. A module is linked dynamically to the initial program: for example, in Java, such a function may be provided by the “classloader” mechanism, and/or code which the initial program has to interpret (i.e. scripts). [0127] These complementary elements may influence the operation of the initial program. [0128] As these elements are sent by push in the service zone, the activity of the application and its composition may develop as a function of the movements (or travel) of the user within the service zone and/or the handling of the tags carried out by the user. Particular Applications [0129] Different particular applications will now be considered. [0130] FIG. 5 shows an example of a particular structure of a guide board with multiple antennas. Here, RFID antennas are used, for example. The board P 50 has an active display zone AS on which symbols S 00 to S 33 appear, arranged in a matrix, for example. The user indicates the destination he wishes to reach by moving his RFID tag towards one of the symbols S 00 to S 33 . [0131] In a first embodiment ( FIG. 5 ) the board P 50 has laterally, in this case on the left-hand side of the active zone SA, at least two long oblique antennas LHR and LLR, of medium range (of the order of one metre) whose radiation axes converge towards the active zone SA. These antennas are for example the models CIPAM CIP_ANT-LF made by Texas Instruments. [0132] The antennas LHR and LLR are permanently reading (in operation) and are provided in order to recognise tags bearing a data word containing a (variable) identification for connection with the carrier and, optionally, a fixed part which amounts to authorisation of access (directly or indirectly). [0133] With this placement of antennas (at least two) relative to the board, when a response is detected from a tag, the power of the signal received is read at each antenna. From this the intersection of at least two arcs of a circle is deduced within the plane of the board, for example LHR 1 and LLR 1 . The intersection located in the active zone SA denotes one of the symbols, in this case S 11 . [0134] Other antenna arrangements may be envisaged, which indicate the intersection of two circles in every case, or several intersections if there are more than two antennas, thus possibly removing the ambiguity that exists when there are two different intersections within the zone SA. The ambiguity may also be removed by following the movement of the tag in front of the board P 50 , as the following of the movement may make one of the intersections improbable. [0135] Alternatively or additionally ( FIG. 6 ), a grid of very short range antennas may be arranged in front of or behind the plane of the board, level with each of the symbols S 00 to S 33 . The antenna closest to the tag then determines which of the symbols S 00 to S 33 is meant. These antennas may be for example the models CIPAM CIP_ANT-LF made by Texas Instruments. [0136] In both cases, the recognition is initiated by a tag held by the mobile terminal/user pair. [0137] The following operations then take place ( FIG. 7 ): at 700 , the user is detected (and a communication address, for example his Bluetooth address), as well as the destination, defined here by the particular zone S 00 to S 33 which is designated by the proximity of the tag (alternatively or additionally, the destination may be defined by a code incorporated in the word that the tag contains). at 702 , these data are sent to the local or remote server. at 704 , dynamic creation by the server of a parameterised application, or griplet, to ensure navigation from the board to the destination. This application may contain, in particular, data specifying the destination, and the cartographic data needed to visualise the journey. at 706 , the server “pushes” this application (griplet) to the user in question, using his communication address. at 708 , the application (griplet) is received on the terminal (telephone) of the user. at 710 , the user launches the application (griplet). Alternatively, the telephone is configured to activate the application (griplet) implicitly on receiving it. This alternative embodiment applies for example where the applications are certified and the telephone is able to verify the origin of the applications. at 712 , the use of the application, in this case a navigation, may begin. [0145] If the destination zone is precise enough, this destination forms the direct objective of the navigation. If not, a restricted list of intermediate locations (e.g. street names) to be reached may be listed for the user. [0146] The navigator displays the map and starts the navigation (pinpointing the current position and the destination). TYPICAL EXAMPLE Contextual Service in an Urban Environment [0147] This relates to notice boards capable of “pushing” griplets containing: a small satellite navigation software, a map and/or a plan of the area and/or a satellite photo and/or a small geographical information system regarding the zone around the board. [0150] Let us assume that the user's terminal has its own GPS receiver (or equivalent) or a displaced GPS head (communicating with the terminal by Bluetooth for example). [0151] All the user has to do is place his RFID close to the appropriate logo on the board (typically placed on the side containing the district map) to start up the navigation griplet almost immediately, without going through a selection menu of applications on the telephone (which is a major advantage in terms of ergonomics on a mobile terminal). [0152] Similarly, when the user has no further use for this navigation griplet and has arrived for example at the entrance to the underground station that he was looking for, it could similarly place his RFID tag close to a board providing him with a griplet dedicated to the underground system (lines, timetables . . . ) or a similar one for the bus service. [0153] If the mobile terminal/user pair does not have a GPS function (or equivalent), it is also possible to navigate from board to board. [0154] Obviously, the guiding application is not restrictive. More generally, the griplet system enables the user to initiate services of assistance, aid or comfort, purely by placing his RFID close to the objects capable of delivering a contextual application of the griplet type, advantageously identified visually by a logo. User Interface [0155] The user interface may comprise the following elements: [0000] a. Displaying a logo or other symbol at the physical object (board, in the embodiment described) capable of providing the information distributed. The logo tells the user that he has only to move close to the logo with his RFID card (or his telephone if the RFID tag is provided on it) in order for the object to “capture” the information he requires. This logo corresponds, in fact, to a “virtual grip”. The card may also be covered by said logo. b. At the user level, it is necessary to provide the option of accessing the contents intuitively, by a movement: in the simplest case (a single “digital object” to be accessed) the movement may simply consist of placing the tag (or the mobile telephone+tag pair) close to the logo. c. When a number of contents are provided, the selection may also be carried out in a “physical” manner: A number of logos are displayed on the menu of contents, To access the selected content, the user moves the tag towards the corresponding logo, For example, an advertising hoarding may have two sides (one map and one advertisement) and provide two associated digital contents; a logo would then be placed on each side, with the appropriate antenna arrangement for detecting both sides. It is also possible to have several contents on each side. A board may also contain several different contents (or the same content/service to be modified) as a function of a particular geometric arrangement on the hoarding: for example an orientation assistance hoarding may display a map and offer the user a navigation service to a destination selected on the hoarding by pointing to it with a tag. An array of antennas (e.g. in a grid pattern) is provided for detecting the different zones to be “pointed out” on the map, as described above. In more complex cases it is also possible to associate commands with movements of tags, for example, moving the tag from right to left facing the logo, or from left to right, would produce two different commands. Here, again, an appropriate array of antennas is provided to detect the transition. [0161] The skilled man will understand that a user interface of this kind enables the user to makes use of dynamic services very easily while still keeping the risk of SPAM (pushing of unsolicited messages) within legal limits. The interface will be capable of being used with future information distribution systems. [0162] Optionally, the board or hoarding may be fitted with a lighting device the light emission characteristics of which, typically its colour, may depend on: the antenna that is currently reading the tag, the communication technology used, the proximity of the tag, the reading of data on the tag, movement, or the like. In particular, the board may be backlit so as to illuminate the antenna currently reading the contents of the tag. Programming and Distribution of Tags [0163] The use of the device according to the invention involves on the one hand the programming of a communication address of the mobile terminal 11 capable of being exploited by the platform 3 in the memory of a tag 17 . Moreover, the tags (or portable objects) have to be given out to the users. [0164] A first solution is to distribute the tags “on site”, i.e. close to the place where the device according to the invention is installed. For example, a desk or collection window may be provided on site for the distribution of tags 17 . A tag 17 may also be delivered at the same time as another service: in an airport, for example, a tag may be handed to the user together with his boarding card, at the check-in desk. [0165] When the communication address is known by the user, typically when it is a mobile telephone number, the address may be recorded in the tag 17 instead of handing out the tag in response to simple information provided by the user. If appropriate, the telephone number may be tested (by a call or by sending a message such as an SMS message, for example) to prevent errors in the number recorded. [0166] However, the communication address may not be known to the user, e.g. if it is a so-called “low level” address such as a material address of a Bluetooth interface. [0167] In this case, the user may be asked to put his telephone into “discoverable” mode, when the wireless communication interface requires it (this is true of Bluetooth, for example). A terminal detecting device that conforms to the wireless technology used can then draw up a list of mobile terminals identified as being present within its range. When the user terminal is identified, a tag is programmed with the address detected and identified. Optionally, a griplet may be sent to the terminal by the push method, and this griplet may in turn interact with the device according to the invention. [0168] In the embodiment in FIG. 2B , a user identifier in a database may be programmed into the memory of the tag 17 . [0169] A second solution is to supply the tag 17 after an ordering step, e.g. using an Internet-service. In this case, a low level address may optionally be detected by the Internet access terminal. For example, a personal computer having a Bluetooth interface can determine the material address of a Bluetooth interface of a mobile terminal. OTHER EMBODIMENTS [0170] In the description of the architecture of the device provided hereinbefore in connection with FIG. 1 , in particular, a control platform 3 arranged locally was considered. However, this control platform 3 may be at least partly displaced. For example, a part of the control platform 3 running the manager 19 and the interface 9 may be arranged locally and connected to a part of the control platform managing the interface 25 . The connection between these parts may take the form of an Internet connection. [0171] The above description relates to the delivery of a contextual service to a user as a function of data specific to this user and utilised by the contextual service. In some cases the contextual service delivered to a particular user may depend on the data specific to a plurality of users put together by the device specific to a number of users. Conversely, a contextual service determined on the basis of data specific to a particular user may be delivered in identical fashion to a plurality of users. [0172] FIGS. 3 and 7 may be seen as illustrating these processes. [0173] More precisely, the invention may also be seen as a local communication process. [0174] Very generally, such a process comprises the following steps: [0000] a. at a selected location, having the use of a plurality of passive portable objects each containing at least one code word, b. providing a plurality of beacons, each capable of interacting with a portable object in order to acquire the code word that it contains, c. in the presence of an interaction between a beacon and a portable object: c1. at least temporarily storing the code word acquired, then c2. implementing a decision mechanism relating to the spontaneous sending of a message, in which the decision to send a message, its contents and/or its destination address depend at least partly on the code word stored. [0178] Of course, this process may be refined according to the different variants listed in the present description. Thus, for example, in the case of the board ( FIGS. 5 and 6 ): step a. is carried out with the board provided in a selected location, while the user has a plurality of passive portable objects each containing at least one code word, as for step b., in the same location as the board in the example, one or more beacons are also provided, each capable of interacting with a portable object 17 , in order to capture the code word that it contains. Finally, in step c., the message may take one of the forms described above, particularly a link to an Internet site, or an executable application. [0182] In the device described, a GSM interface is used. It will be understood that any type of widespread global communication in which the interface is determined by a number known to the user and capable of supporting the sending of messages as described herein may be used. [0183] Similarly, the invention is not limited to a Bluetooth type interface but includes all interfaces that conform to a local wireless communication technology, the interfaces of which can be integrated in mobile terminals, as described hereinbefore. [0184] Finally, this specification has discussed radiofrequency tags of the RFID type, but the invention could equally be used with any device of a reasonable size that is portable, capable of storing data and can be read at a short distance by suitable equipment. [0185] The present invention may be used in an installation such as that described in French Patent Application no. 0503678 filed on 13 Apr. 2005 by the present Applicant, which is hereby incorporated by reference, to all intents and purposes. [0186] The invention is not limited to the embodiments described but encompasses all the variants that may be envisaged by the skilled man within the scope of the claims that follow.

A local communications device comprises a station ( 9, 25 ) for communicating with mobile terminals ( 11 ) and a controller ( 3 ) for transmitting a message of the mobile terminal ( 11 ). The inventive device comprises a beacon ( 19, 21 ) interacting with a portable passive object ( 17 ) for obtaining at least one code word. The controller ( 3 ) interacts with the beacon ( 19, 21 ) for storing the code word thus obtained and for subsequently actuating a decision mechanism relating to a spontaneous message transmission. A decision for transmitting a message depends, at least partially, on the code word.

REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of our application Ser. No. 876,221, filed Feb. 9, 1978, now abandoned. SUMMARY OF THE INVENTION Various anti-bed-wetting devices have been used in the past to train enuretic children to get up in time to empty their bladders and avoid bed-wetting. The first such devices consisted of metallic grids placed under the bedsheet and separated by absorbent but nonconductive material such as cotton cloth. The flow of urine into the bed would activate a bedside alarm shortly after urination by virtue of a circuit being closed and previously nonconducting dry cloth would become conductive when wet by electrolyte-containing urine. These devices have the disadvantage of a moderate delay of between 5 and 10 seconds before the alarm would sound after the onset of urination. There was also the inconvenience necessitated by changes of bed linen during the night. In the past several years different devices have been proposed which are portable and which are activated by urine in the area of the child's perineum or underwear or sleepwear, thereby decreasing the time between the onset of urination and the triggering of the alarm and with the additional advantage of at least theoretically reducing the amount of urine flowing into the bed. The present invention does not claim originality in regard to portability of the device, but does claim to a significant improvement in the state of the art because of the type of sensor employed and, in a preferred embodiment, because of the means of making the electrical connection between the sensor and the alarm, the latter to be worn on the shoulder of the sleeping child. Previous devices have been less than completely acceptable to many children because of the bulkiness of the device in the area of the perineum or the long length of rather stiff electrical cord which necessarily had to reach from the area of the alarm (such as on the wrist, up the arm, and down to the perineal area). An additional disadvantage of previous devices is that the sensor is rather small, covering a very limited area and may be missed by the flow of urine, particularly in boys. If the flow of urine does not hit the metallic buttonlike sensor in such a device, the alarm may not be activated at all and the entire urine flow may be directed into the underlying bed without triggering the alarm. This event has, in fact, been found to occur using this particular type of sensing mechanism. In the present invention to be described, a significant improvement in the state of the art, the sensor consists of a long double strip of conductive vinyl cloth surrounded by a soft cotton flannel tube which is fastened easily to a pair of ordinary undershorts and is connected via special silverimpregnated Velcro® fasteners to a conductive material leading up to the alarm device which is placed in the shoulder region of the child. The polyvinyl cloth strips are readily incorporated into a cotton-covered tube to make a sensor which covers a wide area over the perineum. Such a sensor is soft to the touch and flexible. It can be repeatedly laundered with the underpants to which it is permanently attached by stitching or, more conveniently, iron-on tape. We claim advantages of this particular system for the following reasons: 1. The arrangement is more comfortable than previous devices because of the use of a soft ribbon-like conductor made of cloth which is not noticed by the child in contrast to a stiff wire conductor and therefore makes the device more acceptable and likely to be used by the enuretic child. 2. The sensor to be described covers a fairly wide area of the perineum and is wet easily by urine which is directed either to the right, forward, or to the left, thereby virtually always triggering the onset of urination. 3. Since the sensor device is always in place on the child's undershorts, the child must make no particular effort to place a special button sensor in exactly the right area. In addition, the difficulty of placing a double snap over thick underwear or pajamas is also avoided, a particular difficulty with small children. 4. The use of conductive Velcro® in this instance complements the entire system and can be readily sewn to the conductive vinyl cloth. The Velcro® connect/disconnect system is easy to use by a child of any age and provides a realiable and inexpensive "plug and jack" method of connecting the upper and lower halves of the system. The essence of this invention is the use of a special polyvinyl cloth as a substitute for metallic conductors in at least the sensor and preferably both the sensor and the long lead from the electronic device and alarm which is to be located on the shoulder of the child. The use of the conductive cloth facilitates the use of Velcro® as a connecting device between the upper and lower parts of the system. A particular type of Velcro® is utilized in which the nylon is impregnated with silver. The preferred lead from the shoulder region consists of two thin strips of conductive cloth, each about 3/8 inch wide, which are each enclosed inside separate flat tubes of dacron, thereby insulating the conductive polyvinyl cloth and also giving a smooth, soft surface to the lead which is comfortable to the touch. The upper end of the lead must terminate in an ordinary conductive wire so that such a wire can then be soldered to the proper terminal of the electronic alarm device. This is accomplished at the upper end of the lead by simply folding the polyvinyl strip over a small piece of conductive rubber. A staple then perforates the polyvinyl cloth, the conductive rubber, and the dacron, thereby crimping the wire and rubber very tightly to the polyvinyl cloth. The other end of the wire lead is soldered into the circuit board of the alarm device. At the lower end of the lead, staples are the most convenient method to fasten a small square of conductive Velcro® to a protruding portion of the conductive vinyl strip. A second staple is used to strengthen the attachment of the Velcro® to the dacron tube. Finally, to cover the major portion of the staples and to provide additional strength and improve the appearance, a square of ordinary Velcro® but with a sticky back (furnished as "Scotchmate" by 3M Company) is placed over the backside of the conductive Velcro®. The method described gives a very strong method of attachment which is reliably conductive and of a pleasing appearance. An additional advantage of using ordinary Velcro® on the back of the conductive Velcro® (both are of the nap type) is that one of the pairs of leads can be folded back, as illustrated in the drawings, and fastened to a small piece of hooked Velcro® to prevent inadvertent sounding of the alarm. The sensor strip, which is easily fastened to ordinary underwear by either sewing or with cross strips of iron-on tape, also utilizes conductive polyvinyl cloth. Again, the same advantages accrue with this technique since the cloth is soft and flexible and can be used in conjunction with conductive Velcro® to mate with the leads previously described. Two strips of conductive cloth are employed and advantage is taken of the fact that the cloth as it comes from the manufacturer (Herculite Company) is conductive on only one side and with excellent insulation on the opposite side. Thus, it is possible to provide a very simple sensor wherein two strips of conductive cloth are employed with the nonconductive surfaces in contact with each other. These are enclosed in a simple cotton envelope of very absorbent flannel material. At the upper end of the sensor, provision is made for the attachment of two small squares of conductive Velcro®, which are placed on opposite sides of the sensor. Having the Velcro® squares on opposite sides rather than side-by-side prevents inadvertent touching of the leads and thereby avoids the child inadvertently sounding the alarm as the leads are attached to the sensor. The unit is very sensitive to moisture since a conductive path is established between the two polyvinyl strips whenever a small area of the edge of the sensor becomes moist from urine. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a child wearing a device embodying the sensor of the present invention. FIG. 2 is a perspective exploded view of a device embodying the present invention with some of the parts in section. FIG. 3 is a perspective view of an alternate form of sensor unit. FIG. 4 is a perspective view of another type of sensor unit. FIG. 5 is a section on the line 5--5 of FIG. 4. FIG. 6 is a perspective view of still another form of sensor unit. FIG. 7 is a section on the line 7--7 of FIG. 6. FIG. 8 is a partial exploded view of the structure shown in FIG. 6. FIG. 9 is a perspective view of a sensor wherein the sensing element is formed as part of a garment. FIG. 10 is a perspective view of another sensor unit wherein layers of conductive cloth are placed back to back. FIG. 11 is a side view, partially in section, of the structure shown in FIG. 10. FIG. 12 is an enlarged section on the line 12--12 of FIG. 11. FIG. 13 is an enlarged section on the line 13--13 of FIG. 11. FIG. 14 is a schematic diagram of a simple form of electrical circuit. FIG. 15 is a schematic diagram of another form of warning circuit. FIG. 16 is a perspective view of a child wearing a preferred embodiment of the device wherein both the sensor and the connectors are formed of a conductive polyvinyl cloth. FIG. 17 is an enlarged exploded view of the device shown in FIG. 16. FIG. 18 is an enlarged section on the line 18--18 of FIG. 16. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings by reference characters, a child 11 is wearing a device of the present invention. The device consists of two main parts, namely, an alarm or sounder box 13 and a sensor 15. Sensor 15 is connected to a jack generally designated 17 to a plug 19 connected by suitable wires 21 to the alarm device 13. The alarm box 13 has means for attachment to the upper garment. Preferably, this consists of a patch of Velcro® 23 which mates with a patch of Velcro® 25 which is attached to the upper garment 27 of the wearer. Although hook Velcro® is shown for the pad 23 and loop for the pad 25, this relationship is not critical and can be reversed. The pad 25 is attached to the garment 27 by any suitable means such as sewing or preferably, by a heat-activated iron-on adhesive. The sensor forms part of, or is attached to, the lower portion 28 of the sleeping garment as is hereafter described. The jack 17 and 19 and plug can be of the conventional type used for electrical connectors, but it is preferably made of conductive (silver-impregnated) Velcro® since this results in minimum bulk and is easy for a child to work. This consists of two pads 29 of hook Velcro® fastened to a nonconductive pad 31 which is attached to the upper garment 27 and to the mating loop pads 33 attached to the sensor 15. Obviously, the hook and loop relationship could be reversed. As was previously mentioned, the sensor 15 is of a flexible material which is preferably fastened, by suitable means, to the lower portion 28 of the sleeping garment. In the embodiment illustrated in FIG. 2, the sensor includes a double pouch of a diaper material 35 having a center seam 37. Wires 39 and 41 extend into the two compartments thus formed. The wires 39 and 41 are thin and flexible and preferably of stranded material and are ordinarily made of an inert metal such as stainless steel, silver or bronze. The wires 39 and 41 are attached to the Velcro® pads 33 as previously described. The sensor unit can be sewn into the lower portion of the garment or can be attached by other suitable means such as a heat activated iron-on adhesive. In FIG. 3 another form of sensor unit is shown. In this embodiment of the device, a pad 43 of an absorptive material such as a diaper material is provided with an outer layer 45 of a thin, flexible plastic while the inner surface 47 is not covered. Wires 49 and 51 are exposed or thinly embedded in the open surface 47 of the diaper material. These wires are connected to the conductive Velcro® pads 53 and 55 which mate with the Velcro® pads 29 previously described. FIGS. 4 and 5 show yet another embodiment of the sensor unit and in this embodiment a conductive polyvinyl cloth (such as that manufactured by the Herculite Company) is employed instead of the wires. Referring to FIGS. 4 and 5, two strips 57 and 59 of the conductive cloth are employed and these are held in spaced relationship between an upper layer 61 and a lower layer 63 of a cloth such as diaper cloth. The parts are held together by means of the adhesive layers 65 or can be sewed together with nonconductive thread. The outer layer 61 terminates short of the inner layer 63, leaving a portion of the inner layer exposed as at 67. Tabs of conductive Velcro® 69 are attached to each of the inner layers of conductive cloth. Referring now to FIGS. 6-8, another embodiment of the invention is shown which also uses the conductive polyvinyl cloth. In this embodiment of the invention, the conductive strips instead of being arranged side-by-side are sandwiched together. Thus, there is provided an outer layer 73 and an inner layer 75 of conductive cloth separated by a layer 77 of ordinary cloth such as diaper material. The inner layer 75 has a plurality of perforations 79 therein to permit urine to migrate freely between the layers. The various layers are held together by means of a suitable adhesive 81 or sewn with thread. Conductive Velcro® patches 82 and 83 are connected to the ends of the conductive cloth strips 73 and 75 respectively. The outer strip 73 is notched at 85 and the intermediate strip 75 notched at 87 so that the Velcro® patch 83 will be exposed. Although it is preferred that the sensor be built as a unit and placed in the lower half of a sleeping garment, the sensor can be built into the garment itself as is shown in FIG. 9. In this case, that portion of the garment between the two electrodes would become conductive when wet, thereby completing the circuit and sounding the alarm. Here pants 84 have wires 86 incorporated therein which lead to the Velcro® tabs 88. Of course, strips of conductive polyvinyl cloth could be employed instead of the wires. Another form of sensor is shown in FIGS. 10-13. In this form of sensor unit, the conductive polyvinyl cloth, previously mentioned, is utilized and advantage is taken of the fact that the cloth is conductive on only one side and the opposite side of the cloth is an insulator. Thus, it is possible to provide a very simple sensor wherein two strips of the conductive cloth are employed with the nonconductive surfaces in contact with each other. This is enclosed in a simple cotton envelope of diaper material with the conductive Velcro® contacts on opposite sides. This unit is very sensitive since a conductive path is established around the edges of the sensor through the diaper cloth which forms the envelope. Referring to FIGS. 10-13, the sensor includes a first strip 101 of conductive polyvinyl cloth and a second strip 103. The polyvinyl cloth has a conductive layer 105 and a nonconductive layer 107. The two strips can be placed against each other since the insulating sides are in contact with each other, as shown. The two strips are enclosed in a sheath formed of the layers 109 and 111, which can be of ordinary cotton diaper material formed into an envelope by the side stitching 113. At one end of the strips a small hole 115 is made into each strip of cotton cloth and conductive Velcro® patches 117 and 119 are applied on each side so that the conductive Velcro® patches are in contact with the respective conductive sides of the polyvinyl cloth. This form of sensor is very simple and inexpensive to make and the stitching can pass through the conductive strips of polyvinyl cloth if desired. Further, it has been found that the stitching can go right through the Velcro® pads if the pads are of the hook type. The sensors shown in this embodiment of the invention are very inexpensive to prepare since they can be made in endless strips, sliced into segments, and the Velcro® applied thereto before or after severing the strips into segments. The sensors can be pressed onto a sleeping garment with a hot iron utilizing known binding cloths. They can be easily laundered and will return to their nonconductive form upon drying. With this form of sensor the connectors to the sounder must face each other, rather than being side-by-side as is shown in FIG. 2. Various alarm devices can be used with the sensors of the present invention. In FIG. 14 a simple indicator is shown utilizing a miniature alarm buzzer 90. The positive terminal of battery 92 is connected to the alarm and to an emitter of transistor Q1. The negative terminal of the battery is connected through line 94 to one pole of the sensor and to the emitter of transistor Q2. The opposite terminal of the sensor is connected to the base of transistor Q1 through resistor R1 and the collector of Q1 is connected through resistor R2 to the base of transistor Q2. It is obvious that when there is no conductivity between the two probes of the sensor, no current will flow from the battery to the buzzer since transistor Q2 is cut off. Now if a conductive path is established between the probes of the sensor as by urine, a negative current flows through resistor R1 to the base of transistor Q1 causing Q1 to conduct. When Q1 conducts, the base of transistor Q2 conducts turning on the buzzer 90. If the circuit of a sensor is broken such as by disconnecting the sensor, the buzzing will stop. Thus, the child upon hearing the buzzer can shut the buzzer off by breaking a connection between the upper and lower portions of the garment. In FIG. 15 a preferred circuit is shown utilizing a hexinverter chip such as 74C14 or MC14584 which is designated IC 1 in the drawing. In this circuit, if moisture is present between the electrodes of the sensor 15, pin 1 of IC 1 will go positive causing pin 2 to go low, releasing the clamp diode D1. This permits the Schmitt oscillator formed between pins 3 and 4 to produce a square wave output at a frequency of about 1 Hz. This frequency is controlled by C1 and R3. This is buffered by the trigger between pins 5 and 6 alternately clamping and releasing D2. This permits the oscillator formed between pins 12 and 13 to oscillate at approximately 1 kHz at halfsecond intervals. The parallel connected Schmitt triggers 11 and 10 and 9 and 8 buffer this 50% duty cycle and drive Q3 which in turn drives the speaker 96 to produce an audible tone at about 1 kHz which turns on and off each half second. When the connections to the probe are broken, the circuit turns off. This circuit is preferred because of the on-off nature of the tone which is much more reliable in awakening the sleeper. Referring now specifically to FIGS. 16 through 18, wherein a preferred embodiment of the sensor and connector are shown, the device consists of a sounder, generally designated 100, connected by means of flat strips generally designed 102, to a "plug and jack" unit 104 to the sensor 106. The sounder 100 can be of any type, such as those well-known to those skilled in the art, including those previously described, which have wires 108 and 110, wherein the sounder will be activated when a circuit is established between the two wires. In this embodiment of the invention, the leads consist of two strips 112 and 114 of conductive vinyl cloth, as previously described. These are enclosed in two sheaths 116 and 118 of a soft yet strong fabric such as dacron. At the upper end, a small piece of conductive rubber 120 is attached by means of a small staple 122 which lies along the conductive side of the vinyl cloth. A similar connection is made between the strip 114 and wire 108. A small strip of adhesive tape 124 is placed over the connection to provide strength and insulation. At the opposite end of the strips are placed small pieces of conductive Velcro® 126 and 128. These mate with strips of conductive Velcro® 130 and 132 which are connected to the conductive strips of the sensor strips 134 and 136. In the embodiment illustrated the connector is provided with loop Velcro® and the sensor is provided with hook Velcro®, but obviously this situation could be reversed. The sensor 106 is as previously described and consists of two strips of polyvinyl cloth, each of which has a nonconductive side 138 and 140 and the conductive sides, previously described, 134 and 136. These are held inside of a cloth sheath 142 as previously described. It will be understood that the embodiment shown in 16-18 are the best known mode of practicing the invention since both the sensor proper and the conductors leading from the sensor to the sounder are made of flexible polyvinyl strips. Since the conductors are enclosed in strong cloth, they are not subject to breakage as ordinary wire conductors might be. Further, since they are very soft and flexible, they do not interfere with the comfort of the sleeper. The device of the present invention is ordinarily not provided with an off-on switch so that it is desirable to provide some means of preventing accidental sounding of the device when it is not in use. For this purpose, it is convenient to provide a small pad 144 of Velcro® spaced some distance from the ends 126 and 128 and to provide a small pad 146 of the opposite type of Velcro® on the outer surface of the corresponding conductor. Thus, when the device is not in use, 144 and 146 can be pressed together, obviating any danger of false triggering by contact between 126 and 128. It is believed apparent from the foregoing that we have provided a simple sensor for an anti-bed-wetting device which is very sensitive so that it will be activated by only a few drops of urine. Since the device is actuated by the first few drops of urine, soiling of the bed and clothing is largely prevented. Rapid activation of the device by placing a wetness sensor in the sleepwear is also thought to aid in conditioning the subject to learn to wake up prior to the involuntary release of urine. Further, the preferred form of lead from the sensor to the sounder is strong yet comfortable for the wearer.

An improved moisture-sensing device, preferably combined with an improved lead, is provided which represents a significant advance in the state of the art in the treatment of enuretic children. Both sensor and lead utilize a special type of conductive polyvinyl cloth and the components are connected by silver-impregnated Velcro®.

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/848,765 filed Oct. 2, 2006, the disclosure of which is incorporated herein by reference in its entirety. FIELD OF THE INVENTION [0002] The present invention relates to apparatus and methods for assessing and analyzing the skin and more particularly to digital imaging and analysis of digital photographs taken of a subject. The analysis may be quantitative and comparative relative to another photograph of the same subject taken at another time or relative to a photograph or photographs taken of another person or persons. BACKGROUND OF THE INVENTION [0003] Various imaging systems have been proposed that photographically capture images of a person's face for analysis of the health and aesthetic appearance of the skin. Different images, captured at different times or under different lighting conditions can be used and/or compared to one another to gain insight into the condition of the skin and its response to treatment. This was typically done by human operators inspecting the photographs to identify certain visual indicators of skin condition and to ascertain changes between photographs. It would be beneficial for imaging systems to be less reliant on human perception and manual input. For example, in analyzing the skin, e.g., of a person's face, it is beneficial to examine specific regions of the face for specific associated attributes, since the different regions of the face are specialized in form and function and interact with the environment differently. Some skin imaging systems utilize a trained human operator to identify facial regions by manually touching (a stylus to a touch-sensitive input/output screen) or pointing to (with a cursor and clicking or otherwise indicating) fiducial points on a displayed facial image or drawing (with a stylus or cursor/mouse) polygons on an image to identify the facial regions of interest. While effective, such manual operations are labor intensive and require trained operators. It would therefore be beneficial for imaging systems to identify facial regions on images automatically to increase the speed and consistency of identification of the facial regions and to decrease the reliance upon operator input. [0004] While the science of digital skin imaging analysis has identified various skin responses that are useful indicators of various skin condition parameters, it would still be desirable to identify and use additional specific responses of the skin that are indicative of skin condition. For example, it would be beneficial to identify skin imaging techniques that indicate photodamage and that reliably quantify and measure such indicative skin response. One of the indicators of skin condition is color response. Skin color is also important relative to the selection and design of cosmetics. There are limitations inherent in the expression of color in terms of RGB pixel intensity. It would therefore be beneficial to improve current methods of assessing skin color/brightness, e.g., for assessing skin condition and/or for the selection of and design of skin products, such as cosmetics. [0005] Since imaging is a technical activity using complex apparatus, it remains an objective to improve the user-friendliness of digital imaging and analysis apparatus and to promote the ease and effectiveness of a digital imaging session, as well as enhancing the interaction between therapists/clinicians and patients/clients undergoing digital imaging sessions. SUMMARY OF THE INVENTION [0006] The disadvantages and limitations of known apparatus and methods for skin imaging and analysis are overcome by the present invention, which includes an imaging station for capturing images of a subject in a given ambient lighting environment. The imaging station has a housing with an aperture where the subject is presented for capturing images of the subject, a digital image capture device, a light for illuminating the subject during image capture, and a computer for controlling the image capture device and the light. The housing contains the digital image capture device, and the light and at least partially limits ambient light, if present in the ambient lighting environment, when a digital image of the subject is captured. In one embodiment of the present invention, the imaging station has the capability of taking a plurality of digital images of a subject under a plurality of illuminating conditions, storing, displaying and analyzing the digital images. BRIEF DESCRIPTION OF THE DRAWINGS [0007] FIG. 1 is a diagrammatic view of a digital imaging system in accordance with the present invention. [0008] FIG. 2 is a perspective view of an image capturing apparatus in accordance with an embodiment of the present invention. [0009] FIGS. 3 and 4 are phantom views of the imaging apparatus of FIG. 1 looking from the back and side, respectively. [0010] FIG. 5 is a phantom view like FIGS. 3 and 4 but showing an alternative embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION [0011] FIG. 1 diagrammatically illustrates a digital imaging apparatus 10 having a source of illuminating light 12 (e.g., a photo flash) and a digital camera 14 . An image of the subject S is recorded by the camera 14 in the form of a matrix 16 of pixel values in RGB format (red, green, blue). The matrix 16 of values is typically produced by a Bayer-filtered close-coupled display (CCD) and the information is stored in a memory device, such as random access memory (RAM) of computer 17 or on a flash memory card. The RGB data can be separated into channels or planes, R, G and B, one plane for each color. Various frequencies of illuminating light L I disposed at varying positions relative to the subject S may be used to capture digital images of the subject S in order to capture different information about the skin of the subject. Filters 18 , 20 may be employed on the light 12 and the camera 14 , respectively, to control the light frequency/polarity of light L I which is projected on the subject S, as well as controlling the light L R (reflected or emitted from the subject S), which is admitted into the camera 14 . Imaging of this type is described at length in U.S. patent application Ser. No. 10/008,753, entitled, “Method of Taking Images of the Skin Using Blue Light and the Use Thereof”, which was published as Pub. No. US 2004/0146290 A1, U.S. patent application Ser. No. 10/978,284, entitled, “Apparatus for and Method of Taking and Viewing Images of the Skin”, which was published as Pub. No. 2005/0195316 A1 and U.S. patent application Ser. No. 11/169,813, entitled, “Skin Imaging System with Probe”, which was published as Pub. No. US 2006/0092315 A1, all of which are incorporated in their entirety by reference herein and which are appended hereto as Appendices 1-3. Unless specifically described otherwise, the present invention as described herein in reference to FIGS. 1-4 has the features and functionality disclosed in the foregoing U.S. patent applications. The foregoing applications disclose various correlations between skin condition and the images produced by various photographic parameters, i.e., specific combinations of illuminating light L I , filters 18 , 20 , etc. The skin response to different illuminating frequencies, angles, polarity, etc. can reveal information about skin condition and this evidence of skin condition can be recorded and recalled in digital images for purposes of analysis. [0012] Since the images recorded are in digital form, i.e., in numerical pixel intensity values, the images lend themselves to quantitative analysis, such as by a program or programs residing on computer 17 . For example, instead of just noting that the cheek of a subject whose image is taken at time T 1 is more or less red in color in an image of the person taken at time T 2 , as discerned by a skilled human observer, the values of the intensity of the red pixels in the specific area of the cheek at times T 1 and T 2 may be quantitatively compared. For example, the two values may be mathematically processed to determine the actual change in red intensity for that pixel. Digital image quantification can be used to discern average values for the skin in specified regions, e.g., by summing the values of pixels in the specific region of interest and then dividing by the number of pixels. In this manner, a whole area of skin, e.g., of the face, may be characterized quantitatively. Various other quantified analyses may be conducted, e.g., the imaged area of skin may be tested for standard deviation in pixel intensity. [0013] The present invention recognizes that digital imaging apparatus 10 may include communications apparatus such as modems, e.g., cable and DSL modems, to communicate digital image data and related communications from a digital imaging computer 17 to a remote computer 20 that may be in the home or workplace of an interested person, such as a fellow clinician, cosmetologist, a patient or a cosmetics customer. The receiver can then review the image data and other related communication on the monitor 22 of their computer 20 . These communications may be conducted over the Internet using wired or wireless connections. In addition to sending image data to others, the imaging apparatus 10 may also receive image and related data from others, such as fellow clinicians, patients, etc. via the same means of communication. For example, a cosmetics customer may capture their own image with a local CCD camera 24 and relay that image to the imaging system computer 17 via the Internet, e.g., as an e mail attachment. The image may be examined and a responsive communication prepared by a cosmetologist and sent to the customer. The responsive communication may contain images, e.g., past images taken of the customer that are relevant to the customer, images relevant to cosmetics, etc. These can be sent as attachments to an e mail message. The present invention also recognizes that a cell phone 26 may be used to capture and communicate image information and related communications between parties at the imaging station 10 and parties remote therefrom. [0014] FIG. 2 shows an imaging station 30 having a generally spherical outer housing 32 . The housing 32 may be supported on a flat surface such as a counter or table or be provided with a rotatable mounting, as would be known to one of normal skill in the art. A chin rest 34 is positioned at the open end of a tunnel or “funnel” 36 , which extends into the interior of the housing 32 . At the other end of the tunnel 36 opposite to chin rest 34 , a self-visualizing panel 38 , such as a mirror or alternatively, a display, such as a flat panel display, allows a user of the imaging station 30 to see themselves when they are positioned with their chin on the chin rest 34 . An operator display 40 on the exterior surface of the housing 32 allows an operator, such as a dermatologist, clinician or cosmetologist to view digital images, e.g., those taken of a subject who uses the imaging station 30 . The operator display 40 may be a touch-screen display to function as an operator interface whereby the operator can provide input to the imaging station, e.g., in the form of commands, data, menu selections, or graphic entry by way of drawing on the display 40 with a stylus. After digital images have been captured, the operator display 40 may be used to display the images captured to the operator and to the subject person who can simultaneously view and discuss the images and what is shown in them. [0015] FIGS. 3 and 4 show that the imaging station 30 has a digital camera 42 positioned proximate the self visualizing panel 38 for capturing digital images of a subject person (user of the imaging station). A light 44 , such as a strobe light or other photo flash is positioned proximate to the camera 42 for illuminating the subject when photos are taken. Filter wheels 46 , 48 with associated positioning motors and position sensors (not shown) filter the light emitted from the light 44 and entering the camera 42 , respectively. The light 44 , camera 42 and/or associated filter wheels 46 , 48 , may all be moveable to achieve different orientations for imaging. Computer 50 , e.g., a personal computer (PC), controls the imaging session, providing instructions to the operator through a speaker and/or on the operator display 40 and receiving input from the operator, powering and triggering the light 44 , the filter wheels 46 , 48 and the camera 42 . The digital images are stored in the camera 42 and by the computer 50 on at least one storage device, such as in RAM and/or on a DVD recorder 52 . The housing also contains other necessary peripherals, such as strobe power pack 54 , a power supply 56 for the computer 50 and a power supply 58 for the operator display 40 . The positioning of the various components of the imaging station 30 are determined by their physical packing and accommodation into the housing 34 and may be repositioned as needed depending upon their specific exterior dimensions. [0016] In documenting and assessing skin from cosmetic and health perspectives, the better controlled the light properties (e.g., reflection, scattering, polarization, excitation wavelength and excitation bands), the better the resulting data and analysis of the skin. FIGS. 5 and 6 show light guides 60 and 62 , which can be used to control light emitted from light 44 and captured by camera 42 , respectively. This is because the light leaving a light source (i.e. strobe) will naturally begin to scatter and disperse. Light guide 60 helps to maintain the proper optical properties in order to illuminate a face or other object in order to minimize any interference from surfaces, de-polarization of light or fluorescence of materials (objects or surfaces) other than the analyzed face or object which would cause the light to produce poor quality images. In addition, scatter light captured by camera 42 may interfere with the sharpness of the image. Light guide 62 helps to eliminate the scatter light. The light guides 60 , 62 may be formed of one or more flat or curved surfaces placed in front of the light 44 and camera 42 , respectively. The light guides 60 , 62 may be formed into a square, flare, conical, frustoconical, or round shape hood. Preferably, the color and texture of the interior surfaces 64 of the light guides 60 , 62 absorb light, e.g., painted or made of flat black color. The color and/or texture of outside surfaces should not affect the quality of image captured by the camera 42 . It should be understood that the light guides 60 , 62 depicted in FIG. 4 could be recessed further into the housing 32 by moving the light 44 and the camera 42 deeper into the housing 32 , e.g., behind screen 38 . As a result, the light guides 60 , 62 can be hidden within the housing 32 . As shown in FIG. 5 , the filters 46 ′, 48 ′ can be disposed on a common wheel 47 . [0017] The imaging station 32 may be provided with all the image capture and processing apparatus as described in Publication Nos. 2004/0146290, 2005/0195316 and 2006/0092315, which is contained within the housing 32 . The imaging station preferably has the capability to rotate at least 90 degrees, e.g., either on a supporting surface or rotatable platform and/or to rotate up and down and/or lift or drop in height to accommodate users of various height and seated on various seating arrangements. The tunnel 36 in conjunction with the chin rest 34 and self visualizing panel 38 , cooperate to position the subject person in a maximal position (relative to the light 44 and camera 42 ) for imaging the face of the subject person. The tunnel 36 also reduces the intrusion of environmental lighting during imaging sessions, limits the light projected into the environment when the light 44 is operated during an imaging session and provides the subject person with privacy. The operator display 40 may be used to visualize the subject person, before, during and after imaging, i.e., the camera 42 may be operated in real-time/video mode to show the moving image of the subject person as they place themselves on the chin rest 34 and otherwise prepare to undergo imaging (close their eyes etc.) This real time feed may be used to display the subject on the operator display 40 , as well as on the self visualizing panel 38 (display). In this manner, the operator display 40 may be used to display the view that the camera 42 “sees”. As shown, e.g., in Publication No. 2005/0195316 A1, the camera 45 and illuminating light or lights 44 would be positioned adjacent to the self visualizing panel 38 . In the case of a mirror-type self visualizing panel, the mirror material may be partially or entirely made of “one-way” glass or a half-mirror. Of course, if the functionality of subject self-visualization is not needed or desired, e.g., in the context of an imaging station 30 , which is not intended for subject control or one which relies on verbal commands to the subject and does not need visual cues to the subject, the self-visualizing panel 38 may be omitted or replaced with a clear panel, such as clear glass or plastic. With respect to insuring that the subject person has their eyes closed, the operator display 40 may be used to apprise the operator of this condition, so the operator may then know it is safe to trigger imaging, e.g., by depressing a virtual button on the operator display 40 . [0018] The computer 50 is preferably provided with a plurality of data ports, e.g., USB and or Ethernet ports and/or 1394 “firewire”, wireless capacity or other interface standards for sharing the data captured by the imaging station 30 with other computers, e.g., on a network like the Internet, and for receiving data from other computers for display on the imaging station 30 , e.g., imaging data from population studies, skin care product information, etc. A printer (not shown) may also be used in conjunction with the imaging station 30 to print out images, advice and/or information concerning the skin condition and treatment of the subject person. [0019] As described in a co-pending, commonly owned patent application entitled, Method and Apparatus for Identifying Facial Regions, which was filed on Oct. 2, 2006 as Provisional Application No. 60/848,741 and which is incorporated in its entirety herein, quantitative analysis of skin condition can be facilitated and improved by identifying specific regions of the skin, e.g., of the face. This identification of regions of interest can be conducted automatically through pupil or flash glint identification as fiducial reference points for mapping the facial regions. [0020] As described in a co-pending, commonly owned patent application entitled, Apparatus and Method for Analyzing Skin Using L*a*b* Colorspace, which was filed on Oct. 2, 2006 as Provisional Application No. 60/848,768 and which is incorporated in its entirety herein, identification of skin photo-response indicative of skin condition, quantitative analysis of skin condition, color and brightness can be facilitated and improved by converting digital image data from RGB format to L*a*b* format. As described in Application No. 60/848,768, the process for converting RGB image data to L*a*b* colorspace data is known to one of normal skill in the art, e.g., as described in Charles Poynton, A Technical Introduction to Digital Video (J. Wiley & Sons) Chapter 7, “Color Science.” Application No. 60/848,768 also discloses that facial regions may be identified by an operator marking a displayed image with a cursor tool or by programmatically analyzing the image data to identify pixel values consistent with unique fiducial reference points, such as the pupils, which would have unique color (black or flash glint), shape (round), size, spacing and orientation. Once pupils are identified, facial regions may be calculated relative thereto in accordance with empirically determined spacial/dimensional relationships to the pupils. RGB to L*a*b* conversion may be used to aid in selecting cosmetics for an individual from a palette of available cosmetic colors or may be used to select/design hues of cosmetics in defining a color palette for use by a population. [0021] As described in a co-pending, commonly owned patent application entitled, Apparatus and Method for Measuring Photodamage to Skin, which was filed on Oct. 2, 2006 as Provisional Application No. 60/848,767 and which is incorporated in its entirety herein, the green response intensity of skin to illumination by blue light can be used to identify and quantify photodamage to the skin, e.g., due to the presence of elastotic material. Further, a population's digital skin imaging data concerning photodamage and/or other skin conditions can be characterized numerically and analyzed statistically. Quantitative analysis of digital images of the skin response, such as the degree of variation of green signal response over a surface of the face as an indicator of photodamage, can be used to assess photodamage, and develop a number or score of skin condition relative to a population. [0022] As described in a co-pending, commonly owned patent application entitled, Calibration Apparatus and Method for Fluorescent Imaging, which was filed on Oct. 2, 2006 as Provisional Application No. 60/848,707 and which is incorporated in its entirety herein, a calibration standard may be employed during an imaging session, e.g., during blue fluorescent photography, to identify variations in illumination intensity between images taken at different times. Having identified a circumstance where illumination intensity has varied, the operator of the imaging apparatus can be notified to correct the conditions leading to illumination variations. Alternatively, the imaging apparatus may compensate for the variations by adjusting the intensity of the illuminating light or normalizing the images by digital image processing. [0023] Each of the inventions disclosed in the foregoing applications incorporated by reference may be utilized and incorporated in the imaging station 30 of the present invention. In doing so, certain synergies are realized through their combination and interrelationship. For example, the capability of manually or automatically identifying facial regions has utility in the color ascertainment of certain facial regions, e.g., the cheek or the “average color” of the combination of cheek, forehead and chin. This capability of identifying skin color in certain regions can be helpful in matching cosmetics to those regions or combinations of those regions. For example, in selecting or designing colors for cosmetic foundations, it would be beneficial to know the average color of the facial regions: cheek, forehead and chin and exclude the lips, eyebrows and eyes from the contributing colors. [0024] The identification of facial regions may also be used in the imaging station 30 in conjunction with the teachings of the application directed to ascertaining photodamage, in that specific regions of the skin are more prone to photodamage due to skin composition and exposure likelihood. The calibration of the apparatus and techniques taught in the application pertaining to same can be used in the imaging station 30 in that any set of digital images can be normalized to compensate for variations in illumination intensity as distinguished from variations in response intensity attributable to skin variation. [0025] The imaging station 30 , provides an apparatus and method of obtaining digital image data information concerning the appearance and light response characteristics of a person's skin. Since the present invention can be used by numerous persons, the data obtained from the use of the present invention, as well as data obtained from other sources, such as digital images made by others using different apparatus and methods, may be used to analyze the individual relative to others. As noted, e.g., in the Application entitled Apparatus and Method for Measuring Photodamage to Skin, which is incorporated by reference herein, digital images can be analyzed quantitatively to provide a discrete measurement of skin condition(s). An alternative, traditional method for assessing skin condition is through the judgment of a person based upon the appearance of the image. Over the years it has been shown that experienced clinicians can accurately and effectively discern changes in skin condition, based upon their visual perception, e.g., in comparing two images taken at two different times. Accordingly, the present invention recognizes the value of human perceptive judgments of skin condition in forming an accurate assessment of skin condition. This human perceptive measure can be used in parallel to quantitative, automated methods to confirm one with the other and thereby increase the credibility of both. [0026] The present invention includes a method for training, implementing and testing visual analysis of images of subject persons. More particularly, to train persons to perceptively and accurately judge skin condition based upon images, training sets of images may be assembled. A training set may be a set of images taken of a person over time, which illustrates their skin condition over time. The image set can be divided into various categories, e.g. one category may be images taken with blue light and sensitive to green signal response of the skin to indicate photodamage. The image sets can then be reviewed by one or more person who are trained professionals with a proven proficiency in ascertaining skin condition based upon review of images of the skin of subject persons. The proficient individual or individuals will then order the image set into a range of conditions extending from the worse condition to the best condition. This ordering can be conducted in conjunction with quantified analysis. For example, six images may be considered and arranged from best to worst illustrating the spectrum of skin condition exhibited by the subject person relative to photodamage. Having developed this reference set or training set of images, persons to be trained are taught the visual indicators to look for to discern photodamage. The trainees are then shown the training image set, e.g., two images at a time, randomly selected by a computer, and asked to characterize which of the two displayed images is better or worse, e.g., with respect to photodamage. In presenting the images, the position of the better and worse images (either in the right or left, upper or lower positions on the display) is randomized, such that the display position does not correlate to the skin condition. After the trainees can successfully identify the better and worse images consistently, i.e., match the conclusions of a professional with demonstrated expertise, then the trainee can be adjudged to have assimilated the necessary perception to discern skin condition from digital images. [0027] Assuming that a person is available with suitable training in judging skin condition, the same automated technique of presenting a plurality of images and receiving the judgment of better or worse can be applied to the process of evaluating an individual's skin condition over time. For example, if a person has had a series of imaging sessions, e.g., ten sessions over a period of two years, then a clinician can be automatically and randomly presented with a series of images taken from these imaging sessions and categorize them as better or worse than another image displayed. This process can be repeated until an unbiased repeating pattern of relative ranking is clearly established, demonstrating a reproducible clinical judgment. From this judgment, the subject person can be advised as to when their skin exhibited its best condition, the worse condition, the pattern of improvement or worsening, etc. This type of analysis can be applied to measure the success or failure of treatment and can be used in conjunction with quantitative methods to provide a balanced, informed analysis. [0028] The foregoing methods for training and/or clinically assessing skin condition can be conducted on the imaging station 30 . For example, after an imaging session, the clinician can perform a clinical assessment witnessed by the subject person. [0029] It should be understood that the embodiments described herein are merely exemplary, and that a person skilled in the art may make many variations and modifications without departing from the spirit and scope of the invention. All such variations and modifications are intended to be included within the scope of the invention.

An imaging station for taking a plurality of digital images of a subject under a plurality of illuminating conditions and storing and analyzing the digital images, includes a housing, containing the digital image capturing apparatus, like a camera or video recorder, a computer for processing the image data and one or more displays for displaying images of the person. The imaging station aids in controlling lighting during image capture and may be used to optimally position the subject for imaging. The computer may be programmed to conduct various image processing functions and may be networked to allow image sharing. A display which may be provided on the exterior of the housing allows an operator to visualize the subject and to control the imaging process. The imaging station may be used for teaching purposes.

CROSS REFERENCE TO RELATED APPLICATION [0001] This application is a divisional application of U.S. application Ser. No. 10/345,635, filed Jan. 16, 2003, which is hereby incorporated herein in its entirety by reference. BACKGROUND OF THE INVENTION [0002] This invention relates to surgical needles for tissue ablation, and more particularly, to surgical needles that are for ablation of uterine fibroids. [0003] Approximately 20 to 40 percent of women have uterine fibroids (lieomyomata). In the United States, fibroids result in approximately 175,000 hysterectomies and 20,000 myomectomies each year. Fibroids are well-defined, non-cancerous tumors that arise from the smooth muscle layer of the uterus. Approximately 25% of women suffer fibroid related symptoms, including menorrhagia (prolonged or heavy menstrual bleeding), pelvic pressure or pain, and reproductive dysfunction. [0004] The most common treatments for fibroids include hysterectomy, abdominal myomectomy, laparoscopic myomectomy, hysteroscopic myomectomy, laparoscopy-directed needle mylosis, laparoscopy-directed needle cryomyolysis, high-intensity focused ultrasound ablation of fibroids, and uterine artery embolization. Hysterectomy is a major surgical procedure and carries with it the usual risk of surgery, such as hemorrhaging, lesions, complications, pain, and prolonged recovery. The majority of myomectomies are performed abdominally, wherein a surgeon creates an abdominal incision through which individual fibroids are removed. Abdominal myomectomy and laparoscopic myomectomy, like a hysterectomy, carries the usual risk of surgery. [0005] Radio Frequency (RF) myolysis and thermal tissue ablation are two promising methods for treating fibroids. RF myolysis is a technique in which a RF probe is inserted into a fibroid or the surrounding tissue and then RF energy is applied to the tip of the probe. The tissue surrounding the tip is heated by the RF energy causing necrosis within the tissue. Thermal tissue ablation is a technique that is performed with a cryoablation probe. The cryoablation probe destroys the fibroid tissue by freezing it. [0006] Current methods incorporating RF or cryoablation techniques require direct visualization of the needle tip or electronic imaging. Normally, under direct visualization techniques an endoscope is inserted into the uterus to position the needle. Direct visualization is often problematic because of the difficulties involved in simultaneously manipulating the endoscope and needle. Typically, when electronic imaging is used, the position of the needle is visualized with a hysteroscope or with an external abdominal ultrasound. Hysteroscopy allows direct visualization of the uterine cavity by inserting a small camera on the end of a long tube directly into the uterus through the vagina and cervix. Similar to an endoscope, a hysteroscope must be simultaneously manipulated with the needle, and thus is problematic. Monitoring the probe's position with current ultrasound techniques has a number of drawbacks. For example, a clinician using ultrasound imaging from an external source will have difficulty in distinguishing the uterine tissue from the surrounding organs and precisely locating the needle. [0007] U.S. Pat. No. 5,979,453 to Savage et al. describes a myolysis needle that requires laparoscopic surgery. In laparoscopic surgery the needle must be placed through the uterine serosa into or near the fibroid. As a result, uterine adhesions often form that may cause chronic pain, infertility, and bowel obstruction. Additionally, during laparoscopic surgery the surgeon cannot visualize the tissue below the surface and must blindly place the needle, as a result placement may be sub-optimal. [0008] U.S. Pat. No. 6,146,378 to Mikus et al. discloses a needle placement guide having an endoscope that is inserted into the uterus through the vagina. Using the endoscope, the surgeon positions the endoscopic guide in the correct orientation to the targeted fibroid. After positioning the guide, the endoscope is removed from within the guide and an ablation device is inserted into the guide for subsequent operation on the fibroid. The needle guide suffers from several disadvantages. There is the risk that the needle guide could shift during removal of the endoscope and insertion of the ablation device, resulting in sub-optimal performance. The needle cannot be relocated during the ablation procedure and the endoscope must be reinserted whenever it is necessary to reposition the needle guide. Reinserting and removing the endoscope and ablation device every time the needle must be repositioned increases the time and expense of the surgery. [0009] U.S. Pat. No. 6,379,348 to Onik describes a mylolysis needle that is a combination of a cryosurgical and electrosurgical instrument for tissue ablation. The cryo/electro needle is not easily visualized when in use and requires the use of a dilator to create an access channel in the tissue area where the needle is to be inserted. Similar to laparscopic surgery, placement of the cryo/electro needle is done blindly and may not result in optimal performance. [0010] Thus, a need exists to provide a medical needle system and method that can provide accurate and reliable targeting of fibroid tumors. It is also desirable to provide a needle that has a safety system that would shut-off electrical current to the needle if the uterine wall is punctured. BRIEF SUMMARY OF THE INVENTION [0011] The invention provides a medical needle for transvaginal ultrasound directed reduction of fibroids. The medical needle is adapted for use in conjunction with a transvaginal ultrasound probe. The ultrasound probe has an attached needle guide through which the needle is inserted. The needle has an outer tubular member having an inner surface, a distal end, and a proximal end. The distal end of the outer member is made of an echogenic material so that the tip of the needle has heightened visibility on an ultrasound screen. Located at the distal end is an active electrode that is in communication with a radiofrequency source. An insulating sheath surrounds the entire outer member except for a section that is near the active electrode at the distal end. [0012] The needle has a return electrode that is optionally located on the outer member near the active electrode or on an outer tissue surface of a patient. Optionally, the needle may have a temperature sensor that is located near the active electrode. Typically, the distal end will either be a sharpened pointed tip or a beveled tip that defines an opening in the distal end. [0013] In a preferred embodiment, the needle has a safety device that will turn off power to the active electrode if the tip of the needle should penetrate a patient's uterine wall. In the embodiment possessing a beveled tip, an inner cylindrical member having a forward end and blunt rear end is disposed within the outer member. The inner member has a cylindrical outer section that is electrically conductive and a section that is not electrically conductive. Disposed on the inner surface of the outer member is a second electrically conductive surface and a third electrically conductive surface that are not in communication with one another. The second surface is in communication with the RF power source and the third surface is in communication with active electrode. [0014] A spring is attached to the forward end of the inner member and the blunt rear end extends outwardly beyond the beveled tip. When pressure is applied to the blunt rear end the spring is compressed and the exposed blunt rear end slides backwardly into the outer member. As the inner tubular member slides into the outer member the electrically conductive surface comes in contact with both the second and third surface so that current passes through the surfaces and RF energy is supplied to the active electrode. [0015] In a second embodiment having a safety device, the inner tubular member does not have a conductive surface and there are no second and third conductive surfaces. Rather, a switch is located at the proximal end of the outer member. When pressure is applied to the blunt rear end of the inner member, the inner member slides back into the outer member and thereby closes the switch. When in the closed position, the switch sends a signal to the RF source and RF energy is applied to the active electrode. [0016] In a third embodiment, the needle has an outer member, an inner surface, an echogenic distal end, and a proximal end. As in the first embodiment, the echogenic material results in the tip of the needle having a heightened visibility. Within the outer member is a cryogen tube that extends longitudinally from the proximal end to the distal end. Surrounding a section of the outer member from the proximal end to near the distal end is a cryo-insulation sheath. The distal end is in communication with a cryogen supply so that the distal end can be in cryogenic contact with fibroids. [0017] The length of the needle in all embodiments is typically from about 25 to 50 centimeters, and somewhat more typically between 30 to 40 centimeters. The diameter of the needle in all embodiments is typically from about 12 to 18 gauge, and somewhat more typically from about 16 to 18 gauge. Normally, the needle has a handle at the proximal end that allows the user to easily grip and manipulate the needle. [0018] The invention also includes a method for the electric surgery of fibroids using a transvaginal ultrasound directed echogenic needle. The method comprises the steps of providing a transvaginal ultrasound probe having a transducer and attached needle guide; providing an echogenic needle as described above; inserting the probe into a patient's uterus; inserting the needle into the uterus through the attached needle guide; sensing the location of the needle and fibroid using ultrasound imaging; guiding and positioning the needle on the surface of a fibroid using ultrasound imaging; and passing a controlled amount of RF energy through the fibroid. The method optionally includes the steps of monitoring tissue temperature, penetrating the surface of the fibroid with the distal end of the needle, and the step of turning off power to the active electrode if the distal end pierces the uterine wall. [0019] The invention additionally includes the method for the cryoablation of fibroids in the uterus using a transvaginal ultrasound directed echogenic needle. The method includes the steps of providing a transvaginal ultrasound probe having a transducer and an attached needle guide; providing a cryoablation echogenic needle as described above; inserting the probe into the uterus; inserting the echogenic needle into the uterus through the attached needle guide; sensing the location of the needle and fibroid using ultrasound imaging; guiding and positioning the needle on the surface of a fibroid using ultrasound imaging; delivering a controlled amount of cryogenic supply to the distal end of the needle while it in contact with the surface of the fibroid. The method optionally includes the step of penetrating the fibroid with the distal end of the needle before or after delivering a controlled amount of cryogenic supply. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) [0020] Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein: [0021] FIG. 1 is a side view of a transvaginal ultrasound probe having an attached echogenic needle that has been inserted into a uterus; [0022] FIG. 2 is a perspective view of an ultrasound monitor displaying an echogenic needle that has been inserted into a uterus; [0023] FIG. 3 is a side view of a radio frequency echogenic needle system for use with a transvaginal ultrasound probe; [0024] FIG. 4 is a sectional side view of the needle shown in FIG. 2 ; [0025] FIG. 5 is a sectional side view of a radio frequency echogenic needle having a “shut-off” mechanism; [0026] FIG. 6 is a sectional side view of a radio frequency echogenic needle having a “shut-off” mechanism and a noninsulated segment that is an active electrode; [0027] FIG. 7 is a sectional side view of a radio frequency echogenic needle having a “shut-off” mechanism and an active electrode disposed proximal to the distal end; [0028] FIG. 8 is a sectional side view of a radio frequency echogenic needle having a “shut-off” mechanism and an active electrode disposed in the inner member; [0029] FIG. 9 is a sectional side view of a radio frequency echogenic needle having a switch “shut-off” mechanism; [0030] FIG. 10 is a sectional side view of a cryogenic ablation echogenic needle; and [0031] FIG. 11 is a side view of a radio frequency echogenic needle having a return electrode attached to a patient's thigh. DETAILED DESCRIPTION OF THE INVENTION [0032] The present inventions now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. Indeed, these inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout. [0033] Referring more specifically to the drawings, for purposes of illustration, but not of limitation, there is shown in FIG. 1 an embodiment of the invention referred to generally as 10 . FIG. 1 illustrates an ultrasound probe 100 having the attached mylosis needle 105 that is inserted into the uterus 15 . The ultrasound probe has a transducer located within its tip 30 so that imaging of the uterus and needle are sent to a display for monitoring. Normally, the ultrasound probe 100 includes clamps 35 that attach the needle to the ultrasound probe. Typically, the clamps are made from a metal or plastic material that fits tightly around the probe and has an attached needle guide. The needle guide is typically a narrow or circular opening through which the needle is inserted. Alternatively, the material comprising the clamps is some other hard material that allows the user to manipulate the needle, although not necessarily with equivalent results. The ultrasound probe useful in the invention is any probe that is designed for insertion through the vagina. [0034] As illustrated in FIGS. 1 and 2 , the ultrasound probe 100 is inserted into the uterus through the vagina. Once the probe is in place, the needle is inserted through the needle guide and into the uterus. The physician uses ultrasound imagery to locate the position of fibroids 50 and the needle 105 in the uterus. The tip of the needle 160 is directed against a targeted fibroid or its vascular supply and RF energy, cryogenic, or thermal treatment is applied to the fibroid to cause necrosis of the tissue. In this regard, FIG. 2 illustrates an ultrasound monitor 60 that is displaying ultrasound imaging of an echogenic needle 105 that has been inserted into a uterus 15 . Normally, the probe sends data to an ultrasound unit 65 that processes the data and then displays the resulting images on the monitor. [0035] In all embodiments, the needle will have an echogenic surface 135 at or near the distal end 120 . For example, FIG. 3 shows a bumpy or uneven surface 135 on the outer member. Echogenicity refers to a surface's ability to reflect incident ultrasound waves back to a sensor. The more a surface reflects waves back to the sensor the greater its image will appear on an ultrasound display. Today, there is a variety of different techniques to increase a surface's echogenicity, including grooves or recesses, bumps, coatings, indentations, and the like. In the invention, the echogenic tip enhances its visualization and helps the physician to more precisely position the tip. Normally, the distal end of the needle or a segment proximal to the distal end will have an echogenic surface. [0036] Inserting both the ultrasound probe and echogenic needle into the uterus through the vagina is very advantageous. Traditional laparoscopic myomectomy requires that the ablation needle be inserted into the uterus through the abdomen. During this procedure the needle must be inserted through the uterine serosa, which may result in the formation of uterine adhesions. In contrast, the invention provides an apparatus and method of use for fibroid myomectomy that is a minimally invasive surgical procedure. Adhesions are not expected to form with this method because the echogenic needle is inserted through the vagina rather than penetrating the uterine serosa. A second advantage of the invention is precision and accuracy. The echogenic needle has a heightened ultrasonic visibility that allows the physician to accurately locate and position the needle within the uterus. As a result, the surgical procedure is performed more quickly, the needle is easily repositionable by the surgeon, and most importantly the procedure will have a greater beneficial impact for the patient. [0037] With reference to FIGS. 3 through 10 , needles that are useful in the current invention are illustrated. The needle has an outer tubular member 115 , a proximal end 125 , a distal end 120 , an insulation sheath 200 surrounding a portion of the outer member, and an echogenic surface 135 near the distal end. [0038] As shown in FIG. 3 , a RF needle is broadly designated by reference number 105 . The needle 105 includes an active electrode at the distal end 120 . Typically, the active electrode is a wire, wire loop, metal surface, or the like. The active electrode is in communication with an electrical connector 140 that is attached to the proximal end 125 . The electrical connector 140 is connected to a RF power supply 140 a so that RF current is supplied to the active electrode. The needle 105 is connected to a RF power source 140 a , and optionally to a temperature display (heat readout) 140 b . Normally, the RF source will also include a means for controlling current to the active electrode 140 c . Typically, the RF needles will have a RF insulated sheath 200 that surrounds the outer member 115 and extends from the proximal end 125 to the distal end 120 leaving a segment of the outer member 120 a ( FIGS. 6 and 7 ) that is RF noninsulated. The RF insulation sheath may be made of any material that is suitable to prevent RF energy passing from the outer member to the tissue being treated, such as a heat shrink polyolefin or Teflon®. [0039] The RF needle of the invention delivers either monopolar or bipolar current. With reference to FIGS. 4 through 9 , a RF needle having a return electrode 210 is illustrated. The return electrode is connected to the power supply so that current passes through the active electrode into the fibroid tissue and back to the return electrode. Normally, the return electrode is located on the outer shaft 115 about 2 to 20 millimeters from the active electrode. Typically, the return electrode 210 is positioned in close proximity to the active electrode so that RF energy that passes from the active electrode through the fibroid is focused and does not dissipate within the uterus. Alternatively, as illustrated in FIG. 11 , the return electrode 210 a is located on an outer surface of the patient, such as the thigh or lower back. In this manner, current passes out of the active electrode 175 through the patient's tissue, and into the return electrode 210 a. [0040] In FIG. 4 , the active electrode 175 is depicted at the distal end 120 within the needle. In this first embodiment, the distal end's noninsulated outer surface 150 is electrically conductive so that RF energy passes from the active electrode 175 into fibroid tissue. The distal end 120 has a sharpened tip 160 that can penetrate fibroid tissue to deliver RF energy within the fibroid. As shown in FIG. 4 , the RF needle optionally has a temperature sensor 185 disposed near the distal end 120 . Typically, the temperature sensor will be disposed near the tip of the needle or within the insulation sheath. Normally, the temperature sensor is a thermocouple or thermistor. The sensor provides information that enables the physician to monitor tissue temperature and to adjust the power accordingly. [0041] With reference to FIGS. 5 through 9 , reference number 400 broadly designates a RF needle having a RF energy “shut-off” mechanism. The shut-off mechanism turns off RF energy to the active electrode if the tip of the needle 190 penetrates through the uterine wall. Shutting off power to the active electrode serves several useful purposes. It prevents damage to healthy tissue, which would otherwise be coagulated by RF energy and it alerts the physician that the needle has punctured the uterine wall. [0042] In contrast to the first embodiment, RF needle 400 has a sharpened beveled tip 190 , an inner cylindrical member 405 , and a spring 430 disposed within the outer member 115 at the outer member's proximal end 125 . The inner member 405 is disposed and moveable longitudinally within the outer member 115 . As illustrated in FIGS. 5 through 9 , the inner member 405 has a forward end 407 and a blunt rear end 425 . The forward end 407 is attached to the spring 430 that is connected to the needle's proximal end 125 . In the at rest position, the blunt rear end 425 extends outwardly from the beveled tip 190 and is the first part of the distal end 120 to contact uterine tissue. Applying pressure to the blunt rear end 425 compresses the spring 430 , and the inner member 405 slides longitudinally from the distal end 120 towards the proximal end 125 . As a result, the blunt rear end 425 retracts into the outer member 115 and the beveled tip 190 contacts the surface of the targeted tissue. [0043] In a first embodiment of RF needle 400 , a segment of the inner cylindrical member has a cylindrical conductive surface, and outer member 115 has a second and third conductive surfaces on its inner surface. The second surface is in communication with the RF power supply 140 , and the third surface is in communication with the active electrode 175 . When in the rest position, the second and third surfaces are not in communication with each other. As pressure is applied to the blunt rear end 425 the inner member 405 retracts into a charged position. When in a charged position, the conductive surfaces 410 , 415 , and 420 are in communication and RF energy flows from the RF power source to the active electrode. If the distal end 120 punctures the uterine wall pressure against the blunt rear end 425 will be released and the spring 430 will rapidly extend the blunt rear end 425 outwardly. As a result, the conductive surface 410 will move longitudinally away from the second and third surfaces 415 , 420 and RF energy supplied to the active electrode is shut-off. The exact position of conductive surfaces 410 , 415 , and 420 is not critical except that it is necessary that all three surfaces simultaneously communicate with each other when the inner member is in a retracted position. [0044] In this regard, FIG. 6 shows a conductive surface 410 on the inner member 405 . The conductive surface 410 is optionally located at the forward end 407 of the inner member 405 or at almost any position along the inner member. The second 420 and third surfaces 415 are located on an inner surface 117 of the outer member 115 so that when the inner member 405 retracts the conductive surfaces 410 , 415 , and 420 contact each other. When pressure is applied to the blunt rear end 425 , the spring 430 compresses and the inner member retracts into the outer member 115 . As a result, the conductive surfaces 410 , 415 , and 420 are in communication with one another and RF energy is delivered to the active electrode 175 . [0045] The active electrode is at the distal end 120 or alternatively, the noninsulated surface 120 a of the outer member 115 is the active electrode. In this regard, FIG. 7 illustrates an RF needle having an insulation sheath 435 disposed between the second conductive surface 420 and the outer member 115 . RF energy is supplied to the second surface through a current line 440 that is in communication with the electrical connector 140 . As shown in FIG. 7 , conductive surface 410 on the inner member 405 is in electrical communication with the outer member's 115 inner surface 117 . Typically, the outer member is made from a material, such as stainless steel, that is electrically conductive and suitable for insertion into tissue. When the inner member 405 retracts into the outer member 115 the second surface 420 contacts the conductive surface 410 supplying RF energy to the noninsulated segment 120 a . Optionally, insulation sheath 435 insulates the entire inner surface 117 of the outer member 115 except for segments at the active electrode 120 a and the third conductive surface 415 . [0046] In a second embodiment of a needle having a safety mechanism 400 , the active electrode is located at the blunt rear end. As shown in FIG. 8 , the active electrode 175 is located at the blunt rear end 425 and an electrical connector 425 a extends longitudinally from the conductive surface 410 to the active electrode 175 . The outer member 115 has a second conductive surface 420 that is in communication with RF power supply, but rather than having a third surface in communication with the active electrode, the conductive surface 410 on the inner member 405 is in communication with the active electrode 175 . When pressure is applied to the blunt rear end 425 , the spring 430 compresses and the inner member retracts into the outer member. As a result, the conductive surfaces 410 , 415 contact one another and RF current is applied to the active electrode 175 . Typically, the electrical connector 425 a is disposed within the inner member 405 . [0047] However, the electrical connector 425 a may be disposed between the surface of the inner member and an optional RF insulation sheath that surrounds the inner member. The optional insulation sheath does not surround the conductive surface 410 or the active electrode 175 . [0048] In a third embodiment of a RF needle with a safety mechanism 400 , the inner member is connected to a switch. With reference to FIG. 9 , a needle is shown having an inner member 405 attached to a switch 450 . The switch 450 is in communication with a RF power source via line 455 . As pressure is applied to the blunt rear end 425 the inner member 405 retracts into the outer member 115 and closes the switch 450 . When in the closed position, the switch 450 sends an electrical signal through line 455 to the RF power supply 140 a and RF energy is delivered to the active electrode. The active electrode is located at the distal end and is in communication with the switch, or alternatively, the noninsulated distal end 120 a is the active electrode. [0049] In all the embodiments of a needle having a safety mechanism 400 the inner member 405 is typically made from a material that is non-conductive, such as a plastic. Normally, a non-conductive member will have a conductive material, such as stainless steel, inserted into a surface segment so that the inner member has an electrically conductive surface that will contact the second and third surfaces on the outer member. Somewhat more typically, the inner member is made from a metal such as stainless steel that is surrounded by a RF insulation sheath. The insulation sheath surrounds the inner member except for the conductive surface 410 , which is RF non-insulated. [0050] With reference to FIG. 10 , a cryoablation needle is broadly illustrated by reference number 500 . The cryoablation needle has an echogenic distal end having a sharpened tip 160 . The outer member 115 is surrounded by a cryo-insulation sheath 200 a . The insulation sheath 200 a extends longitudinally from the proximal end 125 to the distal end 120 leaving a segment of the outer member 120 a that is cryo-noninsulated. Normally, the sheath will be made of any material that prevents the cryogenic effect from passing through the outer member and into the surrounding tissue. A cryogen supply tube 510 is disposed within the outer member and extends from the proximal end 125 to the distal end 120 . A cryogen supply source 520 provides cryogen supply through a cryogen connector 525 to the cryogen supply tube 510 . [0051] Typically, cryogenic liquids such as nitrogen, helium and argon are used to produce the cryogenic effect in the targeted tissue. [0052] In all embodiments, it is necessary that the needle is longer than the ultrasound probe and has sufficient length to reach fibroids deep in the uterus. Typically, the length of the needle is about 25 to 50 centimeters, and somewhat more typically about 30 to 40 centimeters. The needle's diameter is dictated by the ultrasound probe's attached needle guide. Typically, the diameter of the needle is about 12 to 18 gauge, and somewhat more typically about 16 to 18 gauge. However, the needle is not limited to the above recited dimensions and may be varied depending upon the actual length of the probe and the needle guide's inner diameter. Typically, the outer member is made of any material that is suitable for insertion into tissue, such as stainless steel. [0053] Optionally, as shown in FIG. 3 , the needle will have a handle 130 at its proximal end 125 . The handle 130 allows the user to easily manipulate and move the tip of the needle. Ideally, the handle 130 is large enough to be manipulated with the user's thumb, index finger and middle finger. Normally, the handle is metal, plastic, rubber, or the like. [0054] Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

The invention is a transvaginal ultrasound probe having an attached echogenic needle that is useful in the treatment of uterine fibroids. The echogenic needle has an echogenic surface near its tip that allows the physician to visualize its location using ultrasound imaging. In one embodiment, the needle has an active electrode at its distal end. The active electrode supplies radio frequency energy to a fibroids causing necrosis of the targeted fibroid or by destroying the fibroid's vascular supply. The radio frequency needle preferably has a safety device that shuts-off energy if the needle punctures the uterine wall. In a second embodiment, the needle has a cryogen supply tube and cryogen supply. This embodiment destroys fibroid tissue by freezing it or its vascular supply when the tissue comes in contact with the needle's frozen distal end. The invention further includes the method of using the ultrasound probe with the attached needle.

PRIORITY APPLICATION [0001] This application claims priority to Great Britain Application Serial No. 1115451.5, entitled “Over-Sampled Single-Sided Subband Echo Cancellation,” filed on Sep. 7, 2011, which is fully incorporated by reference herein. FIELD OF INVENTION [0002] This invention relates to the field of signal processing, and more particularly to echo cancellation. BACKGROUND OF THE INVENTION [0003] Echo cancellation is typically used in telephony to describe the process of removing echo from a voice communication in order to improve voice quality on a telephone call. Adaptive filters are used to model the echo remove the echo from the signal. In telepresence video conferencing systems, the audio signal has high sampling rate and the filter length increases proportionally to the sampling rate. How to manage the computation complexity for high definition audio cancellation is a challenge task. [0004] Echo cancellation has been used extensively in telecommunications, cellular phone and video conferencing. The search for mathematical algorithms to perform echo cancellation has produced many different approaches with varying degrees of complexity, cost, and performance. [0005] In some applications, for example the cancellation of acoustic speech echoes, the echo duration can be extremely long, in the order of 100 msec to 500 msec. A traditional approach to echo cancellation uses an adaptive transversal filter of length L, where L equals the number of samples necessary to extend just beyond the duration of the echo. The computational requirement is proportional to 2 L for the popular LMS class of algorithm, and proportional to L2 or higher for algorithms such as RLS. The more robust algorithms (RLS being one example) have improved convergence characteristics, but the computational load increases dramatically with L. It is also fair to say that the convergence time increases exponentially with the size of L for most algorithms. It is important to have fast convergence, and this is especially true in the example of acoustic speech echo cancellation because the echo path may be continually changing as people and objects move within the environment. An echo canceller that can deal with an echo length of 500 msec or more has problems with computational complexity as well as convergence speed. [0006] In the recent application of Tele Presence systems, the high definition quality of an audio signal with a 48 KHz sampling rate further increases computational complexity (or MIPS requirement) for echo cancellation. A 256 ms. echo tails means a filter length of 12288 samples and adaptation has to be done 48000 times per second. A simple LMS approach will need a 1200MIPS operation. To reduce the computational burden, one commonly known approach, known as sub-band processing, involves separating the speech signal into frequency bands and processing each band separately. This has some inherent advantages, most notably reduced computational complexity, and increased convergence speed. Such as system is described in Q. Jin, K. M. Wong and Z. Q. Luo, “Optimum Filter Banks for Signal Decomposition and Its Application in Adaptive Echo Cancellation”, IEEE Trans. on SP. Vol. 44, No. 7, 1996, pp. 1669-1680, and U.S. Pat. No. 5,937,009, the contents of which are herein incorporated by reference. [0007] Sub-band processing is an attractive approach because it reduces computational complexity. By dividing the signal into M sub-bands, there are M adaptive filters to implement instead of only 1, but these sub-band signals can be down-sampled by a factor of M, consequently the filter outputs need only be calculated 1/M as often. Additionally the length of the filters themselves is reduced from length L to length L/M. This has the overall effect of reducing the computational complexity (not including filter banks) to something on the order of 2 L/M for LMS type adaptive filters, which also improves convergence behavior due to the use of shorter LMS filters. It can be seen that when L is large, there is a significant reduction in computational load, making the overhead necessary for filter banks insignificant. [0008] A typical prior echo cancellation technique using a sub-band filter bank is shown in FIG. 1 . Both echo and reference signal are decomposed into sub-bands and the adaptive algorithm is implemented in each individual band. Finally, the echo-reduced signal is reconstructed with a bank of synthesis filters. [0009] The problem with the sub-band filter bank approach is that the transition between bands makes it impossible to perfectly isolate each band from the adjacent ones without the use of “ideal” band pass filters. “Ideal” in this context means filters with infinitely sharp cut-off. There is a trade-off between the amounts of echo cancellation possible, the filter roll-off, filter group delay distortion, and reconstruct ability of the sub-bands to regenerate the original input signal without distortion. A type of filter known as a QMF is one method of filter bank design that has been used in the past to help overcome these problems. [0010] The main concern with echo cancellation using sub-band decomposition is that the down sampling process creates distortion in each band due to aliasing. This effect causes the echo channel to be time-varying, a violation of an underlying assumption that we need to make in order to apply known methods of adaptive filters for voice echo cancellation. The echo channel must be both linear and time-invariant. Any processing done on the signal decomposition invalidates this property and results in signal distortion. This limits the amount of overall achievable echo cancellation using the method of sub-band decomposition and reconstruction. [0011] One previous approach to fix the aliasing problem is cross-band echo cancellation described in U.S. Pat. No. 5,937,009. It uses adjacent band to cancel the aliasing echo component when the sub-band filter is not a brick-wall filter. The problem with such approach is that the computation complexity for LMS filter increases by three times. SUMMARY OF THE INVENTION [0012] The challenge with HD audio applications is the high audio sampling rate, which means high computational cost and low convergence speed. The present invention finds a compromise between the product cost and echo cancellation perfbrmance. [0013] According to the present invention there is provided a method of echo cancellation comprising splitting an input signal and reference signal into M single-sided sub-bands; downsampling the input signal in the sub-bands at a downsampling rate N, where N≦M; adaptively filtering the single-sided sub-bands; and recombining the filtered sub-bands to produce an output signal. In one embodiment, N<M, so that the signal in the subbands is oversampled. [0014] This invention uses subband technology to reduce the computation complexity and also solves the aliasing problem present in the subband approach. [0015] According to a second aspect of the invention there is provided an echo cancellation circuit comprising an analysis band part wherein an input signal and reference signal are split into M single-sided sub-bands; downsamplers for downsampling the input signal in the sub-bands by a downsampling rate N, where N<M; adaptive filters for adaptively filtering the single-sided sub-bands; and a synthesis band part or recombining the filtered sub-bands to produce an output signal. [0016] The invention is preferably implemented using a polyphase DFT-based filter bank architecture on a real signal to reduce implementation complexity. BRIEF DESCRIPTION OF THE DRAWINGS [0017] This invention will now be described in more detail, by way of example only, with reference to the accompanying drawings, in which:— [0018] FIG. 1 shows a prior art sub-band echo cancellation architecture; [0019] FIG. 2 shows an oversampled sub-band architecture for echo cancellation; [0020] FIG. 3 illustrates the aliasing of a down-sampled signal; [0021] FIG. 4 illustrates the aliasing of down-sampling for a single-sided signal; [0022] FIG. 5 shows an exemplary single sided over-sampled sub-band architecture; [0023] FIG. 6 shows the frequency response of a prototype filter for a DFT-based single-sided sub-band filter bank (M=16); [0024] FIG. 7 shows a polyphase structure for the analysis band in the proposed Architecture; [0025] FIG. 8 shows a polyphase Structure for the synthesis hand in the proposed architecture; and [0026] FIG. 9 shows the polyphase structure for the synthesis band in the proposed architecture with real filter coefficients. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS [0027] One way to solve the aliasing problem is not to use the critical sampling rate. If the signal is decomposed into M bands, the signal downsampling rate N is set as a value smaller than M. This will give us an oversampled filter bank. The oversampled filter bank for echo cancellation is shown in FIG. 2 . The architecture in FIG. 2 is very similar to the one in FIG. 1 . In FIG. 2 the input signal is split into M bands by the analysis filter bank down, and each sub-band is downsampled by downsamplcrs 12 . The filtered subbands are then upsampled by upsamplers 14 passed through a synthesis filter bank 16 and recombined in summer 25 . [0028] The reference signal is likewise split into M subbands by filter bank 18 and downsampled by downsamplers 20 . [0029] Adaptive filters 22 modify the reference signal, which is subtracted from the echo signal in subtractors 24 (Adders with a minus input). [0030] The only difference between FIG. 1 and FIG. 2 is the down sampling rate, after M analysis filter bank for echo and reference signals, is N<M, instead of M. [0031] In general, the smaller the down sampling rate N is, the less the alias is. This is true for the low-pass filter. For a band-pass filter H k (z), if the filter coefficient is real, it will have two symmetrical bands, U k and V k as shown in FIG. 3 . Let input signal be X(z). Passing through H k (z), we have Y(z)=X(z) H k (z). After down sampling N, we have the final analysis band output [0000] 1 N  ∑ n = 0 N - 1  H k  ( z 1 / N  W n )  X  ( z 1 / N  W n ) [0000] with W=e −j2π/N . The aliasing component is X(zW n ) H k (zW n ) for n≠0. [0032] In FIG. 3 ( a ), which shows a critical downsampling rate (N=M), the shift version of U k in X(zW n ) H k (zW n ) (n≠0) will not create aliasing in itself but to V k . For the oversampled signal (N<M), the U k (zW) is further away from U k , and U k (zW −(k−1) ) is further away from V k (as shown in FIG. 3( b )). The aliasing will be reduced for these two components. But the aliasing between U k (zW −k ) and V k increases. The overall aliasing is thus not reduced but increased. [0033] FIG. 4 shows the single sided band decomposition in frequency domain. The single sided band has only one band with complex filter coefficients. Because there is only one band, the number of analysis sub-bands will double that of in FIG. 3 if U k has the same bandwidth for FIG. 3 and FIG. 4 . [0034] FIG. 4( a ) shows the single side band with critical down sampling rate (N=M). The aliasing components for U k mainly come from U k (zW) and U k (zW −1 ). With the oversampled filter bank (N<M), both U k (zW) and U k (zW −1 ) move away from U k , and aliasing will be reduced with decreasing of down sampling rate N. Therefore, the architecture of FIG. 2 with oversampled filter bank (N<M) will reduce aliasing in each sub-band and provide better echo cancellation performance. [0035] For single-sided sub-band decomposition, the decomposed signals are all complex numbers, which means that the multiplication operation will be increased by four times and addition will be increased by twice. Overall MIPS consumption will be possible four times higher for LMS filtering. However, for a real input signal, the sub-band signal has symmetrical property (symmetrical for real part and anti-symmetrical for the imaginary part). This means that it is possible to process only half of sub-band signals, and this will reduce operations by 2 times with a MIPS reduction of ½. The synthesis filter bank is also reduced by half and the final echo reduced signal output will take only the real part of its synthesis output, as shown in FIG. 5 , where unit 28 takes the real part of summer 25 . [0036] In FIG. 5 , we process M/2 bands with a down sampling rate of N (N≦M). The computation reduction (with respect to the whole band LMS algorithm) is 2M/N 2 . If we chose M=16 and N=14, the MIPS requirement will be reduced to 0.1633 of the original value. [0037] All analysis band and synthesis band filters can be derived from a single prototype filter through frequency shifting. This creates a so-called DFT (Discreet Fourier Transform) Based Filter Bank as described in and P. P. Vaidyanathan, “Multirate Systems and Filter Banks” Prentice-Hall, Inc. 1993 Yuan-Pei Lin and P. P. Vaidyanathan, “A Kaiser Window Approach for the Design of Prototype Filters of Cosine Modulation Filterbanks”. IEEE Signal Processing Letters, vol. 5, No. 6, June 1998, pp. 132-134, the contents of which are herein incorporated by reference. [0038] An example of a prototype filter frequency response with linear phase is shown in FIG. 6 with M=16. Let symmetrical linear phase prototype filter be P(z). The analysis and synthesis filter banks can be obtained as H k (z)=F k (z)=P(zW M k ) with W M =e i2π/M . [0039] An exemplary polyphase implementation for analysis and synthesis banks is shown in FIGS. 7 and 8 respectively, where E l (z) is the lth polyphase of P(z) with [0000] E l  ( z ) = ∑ g = 0 ∞  p  (  + gL )  z - gL / N [0000] and W is an L by M/2 matrix with its lmth element being W M lm . W T is the transpose of matrix W. L is the least integer common multiple of M and N such that L/M and L/N are both integers [0040] In FIG. 7 , the input signal s(n) is input to downsamplers 30 through a delay line 31 . The subbanded signals are passed through polyphase filter 32 to matrix multiplication block 34 , which outputs the processed subbanded signals s 0 (n), s 1 (n) . . . In FIG. 8 , the processed subbanded signals y 0 (n), y 1 (n) are input to matrix block 36 , passed through polyphase filter 38 , upsamplers 40 , and through delay lines 35 to unit 42 for extracting the real part of the signal. [0041] The polyphase structure will reduce M/2 filters to one filter with an extra L by M/2 matrix multiplications at reduced sampling rate. These are the extra operations beside adaptive operations and all these operations are dealing with complexity numbers. Therefore, one multiplication is equivalent to four real number multiplication. [0042] If a low pass prototype filter p(n) is used with real coefficients, we can modify the matrix element (W) to be W M lm+1/2 . The end result will be the poly phase filters E 1 (Z L ) (l=0, 1, . . . , L−1) are all real coefficients and the analysis band matrix operation becomes L by M/2 real and complex matrix multiplications, and the MAC operation is reduced by half comparing with two complex number multiplication. The synthesis band matrix operation can also be reduced by half by taking the real output of the matrix multiplications (see FIG. 9 ). The final polyphase filter is done with real numbers. [0043] In FIG. 9 , the processed subbanded signals y 0 (n), y 1 (n) are input to matrix block 44 . Units 46 take the real parts of the output of matrix block 44 and apply them to polyphase filters 48 . The outputs of the polyphase filters are passed through upsamplers 50 and combined with delay line 52 to provide output y out . [0044] Features of the described embodiments include the use of oversampling for sub-band for echo cancellation, single sided DFT based filter bank for echo cancellation, and oversampled single sided DFT based filter bank for echo cancellation. [0045] It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative circuitry embodying the principles of the invention. The invention may be implemented on a processor, which may be provided through the use of dedicated hardware as well as hardware capable of executing software in association with appropriate software. When provided by a processor, the functions may be provided by a single dedicated processor, by a single shared processor, or by a plurality of individual processors, some of which may be shared. Moreover, explicit use of the term “processor” should not be construed to refer exclusively to hardware capable of executing software, and may implicitly include, without limitation, digital signal processor (DSP) hardware, network processor, application specific integrated circuit (ASIC), field programmable gate array (FPGA), read only memory (ROM) for storing software, random access memory (RAM), and non volatile storage. Other hardware, conventional and/or custom, may also be included. The term circuit is used herein to encompass functional blocks that may in practice be implemented in software.

A method of echo cancellation, particularly for use in high definition applications, splits an input signal and reference signal into M single-sided sub-band. The subbanded signals are downsampled at a downsampling rate N, where N≦M, adaptively filtered, and recombined to produce an output signal. The sub-bands are preferably oversampled such that N<M. The use of oversampling and single-sided sub-banding reduces complexity and avoids aliasing problems.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention is directed generally to integrated circuit magnetic memory devices for storing information and, more particularly, to methods and structures for insulating the devices. 2. Description of the Related Art The memory integrated circuit most commonly used in computers and computer system components is the dynamic random access memory (DRAM), wherein voltage stored in capacitors represents digital bits of information. Electric power must be supplied to these memories to maintain the information because, without frequent refresh cycles, the stored charge in the capacitors dissipates, and the information is lost. Memories that require constant power are known as volatile memories. Non-volatile memories do not need frequent refresh cycles to preserve their stored information, so they consume less power than volatile memories. There are many applications where non-volatile memories are preferred or required, such as in cell phones or in control systems of automobiles. Magnetic random access memories (MRAMs) are non-volatile memories. Digital bits of information are stored as alternative directions of magnetization in a magnetic storage element or cell. The storage elements may be simple, thin ferromagnetic films or more complex layered magnetic thin-film structures, such as tunneling magnetoresistance (TMR) or giant magnetoresistance (GMR) elements. Memory array structures are formed generally of a first set of parallel conductive lines covered by an insulating layer, over which lies a second set of parallel conductive lines, perpendicular to the first lines. Either of these sets of conductive lines can be the bit lines and the other the word lines. In the simplest configuration, the magnetic storage cells are sandwiched between the bit lines and the word lines at their intersections. More complicated structures with transistor or diode configurations can also be used. When current flows through a bit line or a word line, it generates a magnetic field around the line. The arrays are designed so that each conductive line supplies only part of the field needed to reverse the magnetization of the storage cells. Switching occurs only at those intersections where both word and bit lines are carrying current. Neither line by itself can switch a bit; only those cells addressed by both bit and word lines can be switched. In some arrangements, one or both of a sense line and a bit line cooperates with a word line to flip the bit. FIG. 1 illustrates, by way of example, the three functional layers of a simple TMR device. TMR devices 10 work by electron tunneling from one magnetic layer to another through a thin barrier layer 12 . The tunneling probability is greatest when the magnetic layers 14 , 16 , on either side of the barrier layer 12 , have parallel magnetizations and least when the magnetizations are anti-parallel. In order for the devices to function properly, these layers must be electrically isolated from one another. Any short-circuiting of the tunnel dielectric layer prevents proper reading of the layers' relative magneto-resistance, which represents the data storage of the device. Materials used in layers of the TMR devices, especially metals such as nickel, iron and cobalt can diffuse out from the devices and into other functional areas of the integrated circuit, especially during subsequent processing steps at elevated temperatures. In the prior art, the dielectric layer 20 shown in FIG. 1 served both as electrical insulation around the magnetic memory devices and as a barrier to outdiffusion of TMR device species. Silicon nitride is the material most often used for this dual purpose. Silicon nitride is a very hard material and tends to make conformal layers. When deposited over the magnetic memory array 10 , the top surface of the silicon nitride 20 is not flat, and a chemical mechanical planarization step is performed before additional processing to form conducting lines that contact the top surfaces of the devices. The high current density carried by the bit and word lines makes copper conductors desirable for MRAM arrays to reduce the likelihood of electromigration. Copper conducting lines are made usually using a damascene process. A copper conducting line 18 , in contact with the bottom of the TMR devices 10 is shown in the plane of the paper in FIG. 1 . To make conducting lines at the top of the devices, first the silicon nitride layer 20 is deposited over the MRAM array. Trenches (FIG. 2) are etched into the silicon nitride layer to make contact with the top surfaces 22 of the TMR devices 10 . If the mask that defines the trenches is even slightly misaligned, the etching step can cause an overetch along the side of the MRAM device. As shown in FIG. 2, when the copper 24 is deposited, it can fill the overetched area as well, making copper regions 26 along the sides of the TMR devices 10 and short-circuiting the devices 10 . Accordingly, structures for and methods of making MRAM arrays with damascene copper conducting lines with greater design tolerance and which will result in increased yield and reliability for MRAM arrays using TMR devices are needed. SUMMARY OF THE INVENTION In accordance in one aspect of the present invention, a memory for an integrated circuit and method of fabricating same are provided. An array of magnetic memory devices, preferably TMR junctions, are configured as individual studs and protrude from a substrate. A layer of insulating spacer material is deposited over the array of magnetic memory devices and a spacer etch is performed to remove the spacer material preferentially from top surfaces of the magnetic memory devices and from substrate surface areas between the magnetic memory devices. Next, a filler dielectric layer is deposited to fill at least regions over the substrate and between the magnetic memory devices. Preferably, the insulating spacer material is also a barrier to outdiffusion of species from the TMR junctions and may consist of silicon carbide (e.g., BLOk™), low temperature silicon nitride or diamond-like carbon. In another embodiment, the insulating spacer material is also a magnetic material and may comprise magnesium-zinc ferrites or nickel-zinc ferrites. The material for the filler dielectric layer may comprise spin-on-glass, borophosphosilicate glass, fluorinated silicate glass or hydrogen silsesquioxane glass. Preferably, the filler dielectric layer can be etched selectively relative to the spacer material. Trenches are etched into the filler dielectric layer to make contact to the TMR devices as for a damascene process. In accordance with another aspect of the invention, an array of magnetic memory cells are provided on a substrate wherein each magnetic memory cell comprises a tunneling magnetoresistance (TMR) structure in a stud configuration, a spacer surrounding the TMR structure and at least two electrodes that make contact to the TMR structure. Regions between and over individual cells are filled with a dielectric material that reflows easily. In one arrangement, the spacer comprises a low k insulator and is a barrier to diffusion of TMR structure species. In another arrangement, the spacer comprises a material with high magnetic permeability. In some arrangements, regions between individual cells have spacer material between the dielectric layer and the substrate, in addition to filler dielectric thereover. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross section of TMR cells in a portion of an MRAM array and having a stud configuration on a substrate, over which a dielectric layer has been deposited according to the prior art. FIG. 2 is a schematic cross section of the MRAM array of FIG. 1 after trench etch and copper deposition, wherein misalignment of the etch mask has caused overetching along one side of the TMR cells. FIG. 3 is a schematic cross section of TMR cells in a stud configuration on a substrate, which form a portion of an MRAM array, constructed in accordance with the preferred embodiments. FIG. 4 is a schematic cross section of the TMR cells of FIG. 3 after a layer of spacer material has been deposited, in accordance with a preferred embodiment of the present invention. FIG. 5 is a schematic cross section of the TMR cells of FIG. 4 showing spacers along the sides of the TMR cells after a preferred spacer etch has been performed. FIG. 6 is a schematic cross section of the TMR cells of FIG. 5 after deposition of a filler dielectric layer to fill the areas between the cells. FIG. 7 is a schematic cross section of the TMR cells of FIG. 6 after etching trenches that expose the top surfaces of the TMR cells. FIG. 8 is a schematic cross section of the TMR cells of FIG. 4 showing spacers along the sides of the TMR cells and residual spacer material on horizontal surfaces after a partial spacer etch has been performed in accordance with an alternative embodiment. FIG. 9 is a schematic cross section of the TMR cells of FIG. 8 after deposition of a dielectric layer to fill the areas between the cells and after trenches have been etched and residual spacer material has been removed, thus exposing the top surfaces of the TMR cells. FIG. 10 is a schematic cross section of the TMR cells of FIG. 9 after copper has been deposited to fill the trenches and the top surface has been planarized. FIG. 11 is a collapsed top view of an array of TMR cells showing metal lines making contact to the cells both above and below the cells. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT It is well-known that cells employing the tunneling magnetoresistance (TMR) effect can be used for making magnetic random access memory arrays (MRAMs). The embodiments of this invention can be used to advantage on TMR MRAMs having any of a number of TMR stack configurations and fabricated by any of a number of methods. The figures show the simplest configuration for illustrating the preferred embodiment. Generally, a TMR stack comprises a stack of layers that includes a layer of pinned hard magnetic material, a stack of layers that includes a sense layer of soft magnetic material and a tunneling dielectric layer separating the two stacks. An exemplary stack below the dielectric includes a tantalum seed layer, a nickel-iron seed layer, a magnesium oxide pinning layer and a nickel-iron or nickel-iron-cobalt pinned layer. An exemplary tunneling dielectric layer over this stack comprises aluminum oxide. An exemplary stack over the tunnel dielectric includes a nickel-iron or nickel-iron-cobalt sense layer, a tantalum barrier layer and a tungsten nitride layer. As shown in FIG. 3, the description of the first embodiment will use, as a starting point, an array of TMR cells 10 having stud configurations and protruding from a substrate that may contain other devices consistent with integrated circuit manufacture. The cells 10 have a similar construction to that described above with respect to FIG. 1 . It is preferred that the top layer 30 of the TMR cells comprises a conductive barrier layer comprising tantalum in the illustrated embodiment. Just below the TMR cells and making electrical contact with them are a series of parallel conductive lines, preferably comprising copper, one of which 18 is shown contacting the devices and in the plane of the page in FIG. 3 . In the illustrated embodiment of the current invention, a blanket layer of spacer material 40 is deposited over the MRAM array, as shown in FIG. 4 . In one arrangement, the spacer material comprises Si 3 N 4 . Preferably, the spacer material is a low k electrical insulator to prevent shorting out the memory devices. Preferably the value of k is less than 3.5, more preferably less than 3.0. The thickness of the deposited spacer layer is preferably between about 5 nm and 100 nm, more preferably between about 20 nm and 40 nm. Preferably, the spacer material comprises a material that acts as a barrier to outdiffusion of metals from the TMR stack. Materials that have these characteristics include low temperature silicon nitride (apart from the low k characteristic), diamond-like carbon and silicon carbide, preferably as produced by the BLOk™ (Barrier LOw k) chemical vapor deposition process of Applied Materials in Santa Clara, Calif. Alternatively, the spacer layer 40 comprises a material that, in addition to having a low k and being a diffusion barrier, has high magnetic permeability and low coercivity. In one arrangement, the magnetic permeability is between about 10 and 1 gauss/oersted, and the coercivity is less than about 0.1 oersted. In another arrangement, the magnetic permeability is between about 1 and 2 gauss/oersted, and the coercivity is less than about 1.0 oersted. Such a material additionally provides protection from stray magnetic fields for data stored in the device. Preferred materials for magnetic protection include dielectric magnetic materials, such as magnesium-zinc ferrites ((MnZn) O. FezO 3 ) and nickel-zinc ferrites ((NiZn) O. Fe 2 O 3 ). The spacer layer is deposited by any suitable process, including physical vapor deposition or chemical vapor deposition. The spacer layer is etched, preferably using an anisotropic etch process that preferentially etches the horizontal portions 42 of the spacer layer 40 . More preferably, the spacer etch is selective against etching tantalum, thus allowing the tantalum layer 30 to act as an etch stop and protecting the TMR memory structures. A physical process, such as ion milling, can be used for all spacer materials. Preferably, the spacer etch has a chemical component and is a reactive ion etch (RIE). Preferred etchants for silicon carbide include CF 4 , CH 2 F 2 and C 2 F 6 . Preferred etchants for silicon nitride include CF 4 and CHF 3 . Preferred etchants for diamond-like carbon include oxygen-based plasma. Preferred etchants for magnesium-zinc ferrites and nickel-zinc ferrites include Cl 2 - and CF 4 -based RIE. The spacer etch leaves a plurality of spacers 50 over sidewalls of the MRAM devices 10 , as shown in FIG. 5, wherein all spacer material has been removed from horizontal substrate surfaces 52 and from top surfaces 54 of the devices 10 . A filler dielectric layer 70 is deposited over the MRAM array, as shown in FIG. 6 for the illustrated embodiment. The thickness of the filler dielectric layer 70 is preferably between about 50 nm and 150 nm, more preferably, between about 100 and 120 nm. Because the TMR cells 10 are surrounded by the spacers 50 , which are barriers to outdiffusion of TMR species, choice of a dielectric fill material is not limited to those with good diffusion barrier properties. Softer dielectric materials than the silicon nitride can be used. One benefit is that softer materials flow well and are better able to form flat, smooth surfaces 72 , even over varied topography. These kinds of materials are reflowable, so chemical-mechanical planarization is not necessary, thus saving valuable time in processing and avoiding the contamination and other problems associated with a separate planarization step. Another benefit is that dielectric materials can be chosen with k values less than that of silicon nitride, thus lowering the RC delay of the memory array. Furthermore, replacing a thick silicon nitride layer with the softer oxide-based materials, preferably reflowable materials, also reduces stress in the integrated circuit. Reduced stress, in turn, leads to less defects and higher yield for the fabrication process. It is also preferred that the filler dielectric material 70 is selectively etchable in relation to the spacer material. Preferred dielectric materials include SOG (spin-on glass), BPSG (borophosphosilicate glass), FSG (fluorinated silicate glass) and HSG (hydrogen silsesquioxane glass). These materials can be deposited by chemical vapor deposition or any other suitable method. In FIG. 7, a set of parallel damascene trenches 80 , shown perpendicular to the page and to the copper line 18 below the TMR devices 10 , has been etched to expose the top surfaces 54 of the devices. In the illustrated embodiment, the top surface 54 of the TMR structure 10 comprises tantalum with no residual spacer material thereon. The tantalum layer 30 acts as an etch stop, protecting the TMR structure during the dielectric trench etch. The preferred spacers 50 also alleviate problems of mask misalignment. Over the TMR cells 10 are trenches 80 that are also perpendicular to the page. In the final structure, conducting metal lines (not shown) fill the trenches 80 , making electrical contact to the top surfaces 54 of the TMR cells 10 and have top surfaces level with the top surface of the fill dielectric 70 . An alternative embodiment is shown in FIG. 8, wherein a small amount of spacer material 60 , 62 remains both on the substrate 18 and on the top surface 54 of the device 10 , respectively. As stated above, the spacer material is preferably an electrical insulator, more preferably low k, so it does not short across the tunnel dielectric nor does layer 60 short devices to one another. The remaining spacer material 62 over the memory devices 10 can be removed either during the etch process that creates trenches 80 in the filler dielectric layer 70 for the metal contact or from a second etch process used specifically to remove the spacer material after the trenches 80 have been formed. FIG. 9 shows the structure after a filler dielectric layer 70 has been deposited, trenches 80 have been etched and residual spacer material 62 has been removed. FIG. 10 shows the resulting structure of the alternative embodiment, after damascene processing to make conducting lines 82 in contact with the devices 10 . A layer of copper was deposited over the trenches 80 and the filler dielectric layer 70 . The copper layer was then planarized, leaving copper conductive lines 82 in the trenches and no copper over the dielectric surface. There is residual spacer material 60 between the substrate 18 and the filler dielectric layer 70 . As stated above, with reference to FIG. 4, the filler dielectric material 70 is preferably selectively etchable in relation to the spacer material. Even if the mask that defines the trenches is slightly misaligned, the trench etch step will not cause an overetch along the side of the TMR device as was shown in the prior art of FIG. 2 . For the embodiment of FIG. 10, even if overetch occurs outside the spacers, the barrier 60 prevents shorting. The process used to etch the dielectric material 70 is selective against the spacer 50 . No gaps along the sides of the device will develop, and the copper will not short out the device. Thus greater design tolerance has been achieved for making MRAM arrays with damascene copper conducting lines. FIG. 11 shows a top view of a portion of an MRAM array in accordance with preferred embodiment of the current invention. A few layers can be seen in this drawing. The TMR structures 10 are shown as rectangular, and the spacers 50 make continuous contact along all four sides. Alternatively, the TMR structures can have any anisotropic shape. The top conducting lines 82 are seen as a set of parallel lines making contact to the top surfaces of the TMR cells 10 , which are arranged in an array. In a parallel plane, below the plane of the paper and perpendicular to lines 82 are another set of parallel conducting lines 18 in contact with the bottom surfaces of the TMR cells 10 . Between the conducting lines 18 , 82 , are regions of filler dielectric material, configured as columns 70 of material perpendicular to the page. Although it cannot be seen in this view, this filler dielectric material also fills the regions between lines 82 at the top and lines 18 at the bottom of the TMR cells 10 . The preferred embodiments have been described herein in considerable detail to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to the equipment and operating procedures, can be accomplished without departing from the scope of the invention itself.

A memory for an integrated circuit and method of fabricating same are provided, comprising providing an array of magnetic memory devices, preferably TMR junctions, that are configured as individual studs and protrude from a substrate. A layer of insulating spacer material is deposited over the array of magnetic memory devices, and a spacer etch is performed to remove the spacer material preferentially from the top surfaces of the magnetic memory devices and from substrate surface areas between the magnetic memory devices. Preferably, the insulating spacer material is low k and/or a barrier to outdiffusion of species from the TMR junctions. Examples include silicon carbide (BLOk™), low temperature silicon nitride or diamond-like carbon. In another embodiment, the insulating spacer material is also a magnetic material and may comprise magnesium-zinc ferrites or nickel-zinc ferrites.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to an improved belt pulley and to a method of making such a belt pulley or the like. 2. Prior Art Statement It is known in the art to provide a belt pulley having a hub and a peripheral groove for receiving part of an endless belt therein that is to drive the pulley or be dirven thereby whereby the pulley is adapted to be rotated about the axis of the hub, the pulley having a plurality of radially disposed fins extending outwardly from at least one side thereof. However, it is believed that no cover plate covers such fins so as to provide closed passages between the fins except at the inlets and outlets thereof. However, it is known in the disc brake art to provide in the disc brake rotor a plurality of radially disposed passage means each provided with an inlet adjacent the hub of the brake rotor and an outlet adjacent the outer periphery of the brake rotor whereby fluid passing through the passages from the inlets thereof to the outlets thereof will tend to cool the brake rotor as the brake rotor rotates about the axis of the hub thereof, the passage means each being defined between a pair of radially disposed vanes. It is also known to provide a belt pulley having a hub and a peripheral groove for receiving part of an endless belt therein that is to drive the pulley or be driven thereby whereby the pulley is adapted to be rotated about the axis of the hub, the groove of the pulley defining an annular bottom surface of the groove and a pair of spaced apart angled inside surfaces of the groove that join with the bottom surface and diverge away from each other as the angled surfaces extend away from the bottom surface. The angled surfaces are adapted to be engaged by opposed angled sides of the belt in such a manner that the bottom of the belt will be spaced from the bottom surface. The pulley has opposed outer sides. The pulley has means defining at least one passage means provided with an inlet interrupting one of the opposed outer sides adjacent the hub and an outlet interrupting the bottom surface of the peripheral groove whereby fluid passing through the passage means from the inlet to the outlet thereof will tend to cool the pulley and the belt as the pulley rotates about its axis. For example, see British Pat. No. 865,797. SUMMARY OF THE INVENTION It is one feature of this invention to provide an improved belt pulley having improved means for cooling the same. In particular, it is known that belt life, particularly in high ratio or high load drives (including vehicle drives such as continuously variable transmissions and automotive accessory drives as well as industrial type drives) is limited largely by belt operating temperature. Accordingly, it was found according to the teachings of this invention that the operating temperature of a belt being utilized with a ventilated pulley of this invention is reduced if the pulley has at least one passage means provided with an inlet adjacent the hub of the pulley and an outlet adjacent the peripheral groove of the pulley whereby fluid passing through the passage means from the inlet thereof to the outlet thereof will cool the pulley and/or the belt as the pulley rotates about the axis of the hub thereof and thereby increases the life of the belt. For example, one embodiment of this invention provides a belt pulley having a hub and a peripheral groove for receiving part of an endless belt therein that is to drive the pulley or be driven thereby whereby the pulley is adapted to be rotated about the axis of the hub. The groove of the pulley defines an annular bottom surface of the groove and a pair of spaced apart angled inside surfaces of the groove that join with the bottom surface and diverge away from each other as the angled surfaces extend away from the bottom surface. The angled surfaces are adapted to be engaged by opposed angled sides of the belt in such a manner that a bottom of the belt will be spaced from the bottom surface. The pulley has opposed outer sides. The pulley has means defining at least one passage means provided with an inlet interrupting one of the opposed outer sides adjacent the hub and an outlet interrupting the bottom surface oo the peripheral groove whereby fluid passing through the passage means from the inlet to the outlet thereof will tend to cool the pulley and the belt as the pulley rotates about the axis of the hub, the means defining the passage means defining the passage means so that a substantially straight line extending from a centerline of the passage means that passes from the inlet to the outlet thereof will engage against one of the angled surfaces without engaging against the bottom of the belt. Accordingly, it is an object of this invention to provide an improved belt pulley having one or more of the novel features of this invention as set forth above or hereinafter shown or described. Another object of this invention is to provide an improved method of making such a belt pulley, the method of this invention having one or more of the novel features of this invention as set forth above or hereinafter shown or described. Other objects, uses and advantages of this invention are apparent from a reading of this description which proceeds with reference to the accompanying drawings forming a part thereof and wherein: BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary, isometric view looking toward the front end of an automotive engine which is adapted to utilize any one of the pulleys of this invention, FIG. 1 illustrating one of the pulleys of this invention and having a part thereof exploded therefrom. FIG. 2 is a view looking perpendicularly toward the front end of an automobile engine of FIG. 1. FIG. 3 is an enlarged, exploded perspective view of the belt pulley of this invention that is utilized in FIGS. 1 and 2. FIG. 4 is a cross-sectional view taken on line 4--4 of FIG. 5 and illustrates the belt pulley of FIGS. 1-3. FIG. 5 is a cross-sectional view taken on line 5--5 of FIG. 4. FIG. 6 is an exploded perspective view similar to FIG. 3 and illustrates another embodiment of the belt pulley of this invention. FIG. 7 is an exploded perspective view similar to FIG. 3 and illustrates another embodiment of the belt pulley of this invention. FIG. 8 is an exploded perspective view illustrating another belt pulley of this invention. FIG. 9 is an end view of FIG. 10 and comprises the belt pulley of FIG. 8. FIG. 10 is a cross-sectional view taken on line 10--10 of FIG. 9. FIG. 11 is a view similar to FIG. 9 and illustrates another belt pulley of this invention. FIG. 12 is a cross-sectional view taken on line 12--12 of FIG. 11. DESCRIPTION OF THE PREFERRED EMBODIMENTS While the various features of this invention are hereinafter illustrated and described as providing a belt pulley of a particular motor vehicle engine, it is to be understood that the various features of this invention can be utilized singly or in any combination thereof to provide a belt pulley for other belt systems as desired. Therefore, this invention is not to be limited to only the embodiments illustrated in the drawings, because the drawings are merely utilized to illustrate one of the wide variety of uses of this invention. Referring now to FIGS. 1 and 2, an automobile engine is generally indicated by the reference numeral 20 and utilizes an endless power transmission belt 21 for driving a plurality of driven accessories as hereinafter set forth, the improved pulley of this invention being generally indicated by the reference numeral 22 in FIGS. 3-5 and being adapted to be utilized to provide a cooling effect on the belt 21 in a manner hereinafter set forth. The endless power transmission belt 21 may be of any suitable type known in the art and is preferably made primarily of a polymeric material. The belt 21 in FIGS. 1 and 2 is of a generally rectangular cross-sectional configuration and has a bottom driving surface 21' and a top driving surface 21" in a manner well known in the art, the belt 21 being ribbed or non-ribbed as desired. However, it is to be understood that the various features of this invention as hereinafter set forth are adapted to operate on belt constructions having other cross-sectional configurations whereby the various embodiments of the pulleys of this invention illustrated in FIGS. 3-12 are illustrated as providing pulleys for belts that have a generally trapezoidal cross-sectional configuration as is well known for V-belt constructions with the understanding that the various pulleys of this invention can be modified in a manner well known in the art to operate on belts of other cross-sectional configurations as desired. The belt 21 is driven by a pulley portion 23 of the pulley 22 of this invention which is operatively interconnected to the crankshaft of the engine 20 in a manner well known in the art whereby the pulley 22 is a driven sheave or pulley. The driving pulley 22 drives the belt 21 in an endless path and thereby drives a sheave or pulley 24 of a power steering device used in an automobile (not shown) utilizing the engine 20, a sheave or pulley 25 of an engine water pump, a sheave or pulley 26 of an air pump of a type used in an antipollution system for the engine 20, a sheave or pulley 27 of an engine electrical alternator 28 and a sheave or pulley 30 of a compressor 31 of an airconditioning system for the automobile utilizing the engine 20. All of the driven accessories, through their sheaves or pulleys 24, 25, 26, 27 and 30 impose a load on the belt 21 as is well known in the art whereby the same impose a heating load to the belt 21, the driving pulley 22 and engine 20 also imposing a heating load to the belt 21 as is well known in the art. As previously stated, it is one feature of this invention to provide the pulley 22 with means that tend to cool the belt 21 during its operation. In particular, the pulley 22 as illustrated in FIGS. 1-5 comprises a conventional pulley portion 23 and a ventilating device of this invention that is generally indicated by the reference numeral 32 in the drawings and having a plurality of passage means passing therethrough, each passage means being generally indicated by the reference numeral 33. The pulley portion 23 has opposed substantially parallel flat sides 34 and 35 and is provided with a hub 36 and a peripheral groove 37, the hub 36 being adapted to be secured to a suitable drive or driven shaft 38 in a manner well known in the art while the peripheral groove 37 is adapted to receive part of an endless transmission belt therein in a manner well known in the art which comprises the belt 21 in FIGS. 1 and 2 and a V-belt 39 in FIGS. 3-5. The ventilating device 32 of this invention comprises a pair of substantially flat disk-like plates 40 and 41 secured together with a plurality of substantially flat and radially extending vanes 42 disposed therebetween and cooperating with the inner sides 43 and 44 of the plates 40 and 41 to define the plurality of radially disposed passages 33 with each passage 33 being disposed between an adjacent pair of vanes 42 and having an inlet 45 adapted to be disposed adjacent the hub 36 of the pulley 22 and an outlet 46 adapted to be disposed adjacent the peripheral groove 37 of the pulley 22 when the plate 41 of the ventilating device 32 is secured against the side 34 of the pulley portion 23 in the manner illustrated in FIGS. 3-5. The plate 41 has a central opening 47 passing therethrough of a size and configuration to permit the same to be secured to the drive or driven shaft 38 while the plate 40 has a larger central opening 48 passing therethrough to provide an enlarged passage or opening leading to the inlets 45 of the passages 33 as illustrated in the drawings. While the pulley portion 23 and ventilating device 32 can be formed of any suitable material, it is believed that the same should be formed of material having a high coefficient of heat conductivity, such as metallic material, in order to optimize the amount of cooling from the air flowing through the passages 33. In particular, as the pulley 22 is being rotated by the belt 39 or is being rotated by the shaft 38 as the case may be, it is believed that a centrifugal force is created through the rotation of the pulley 22 which will force an air flow through the passages 33 thereof from the inlets 45 thereof to the outlets 46 thereof and thereby in much the same manner as a Venturi arrangement will cause fresh air to continuously flow into the inlets 45 of the passages 33 whereby the constant flow of air through the opening 48 of the plate 40 and through the passages 33 will through conduction cool the pulley 22 and, thus, cool the belt 39 so that the pulley 22 provides a cooling effect on the belt 39 in the operation of the system utilizing the pulley 22 and belt 39, such as the system illustrated in FIGS. 1 and 2. While the vanes 42 could be formed separate from the plates 40 and 41 and be secured thereto in any suitable manner, the pulley 22 is illustrated in FIGS. 3-5 as having the vanes 42 formed integrally in a one-piece manner with the plate 41 while the plate 40 is subsequently secured to the vanes 42 as illustrated. However, it is to be understood that other arrangements can be utilized to provide for the air flow passages 33. For example, reference is now made to FIG. 6 wherein another pulley of this invention is generally indicated by the reference numeral 22A and parts thereof similar to the pulley 22 previously described are indicated by like reference numerals followed by the reference letter "A". As illustrated in FIG. 6, the pulley 22A comprises the standard pulley portion 23A and a ventilating means 32A of this invention which comprises the plate 40A having the vanes 42A integral therewith and being adapted to be secured directly to the side 34A of the pulley 23 without having the intervening plate 41 of the ventilating means 32 previously described. If desired, the side 34 of the pulley 23 could have the vanes 42 integral therewith. In particular, reference is now made to FIG. 7 wherein another pulley of this invention is generally indicated by the reference numeral 22B and parts thereof similar to the pulleys 22 and 22A previously described are indicated by like reference numerals followed by the reference letter "B". As illustrated in FIG. 7 it can be seen that the pulley portion 23B has the plurality of vanes 42B integrally formed on the side 34B thereof and that the plate 40B is adapted to be secured directly to the vanes 42B to form the passages 33B to function in the manner previously described for the passages 33 of the pulley 22. While the various pulleys 22, 22A and 22B each has a single peripheral groove 37, 37A and 37B therein, it is to be understood that the various pulleys of this invention can have more than one belt receiving peripheral groove and more than one ventilating means. For example, reference is now made to FIGS. 8-10 wherein another pulley of this invention is generally indicated by reference numeral 22C and parts thereof similar to pulleys 22, 22A and 22B previously described are indicated by like reference numerals followed by the reference letter "C". As illustrated in FIGS. 8-10, the pulley 22C includes a plurality of pulley portions 23C disposed in axial aligned relation and having a plurality of ventilating means 32C of this invention arranged and secured therewith in an alternating manner so that a ventilating unit 32C is disposed outboard of the pulley portions 23C at each end of the arrangement while a ventilating means 32C is disposed between each adjacent pair of pulley portions 23C as illustrated. Additionally, a hub member 49 is disposed in and secured to the pulley portions 23C and is adapted to be splined or otherwise fixed to the drive or driven shaft 38C in any suitable manner, the hub member 49 having a plurality of grooves 50 formed longitudinally along the same and each being adapted to be disposed in fluid communication with the venting devices 32C that are disposed intermediate the pulley portions 23C. In fact, the vanes 42C of the intermediate venting devices 32C of the pulley 22C can have the inner ends 51 thereof spaced from the hub 49 so that the grooves 50 will be in full communication with all of the passages 33C of the devices 32C that are disposed intermediate the pulleys 23C as illustrated, the outboard ventilating devices 32C having the openings 47C and 48C thereof at least as large as the outer diameter of the hub 49 to assure that the passages 50 thereof will be in fluid communication with air outboard of the pulley 22C so as to be drawn therein by the aforementioned centrifical action of the pulley 22C. While the various pulleys of this invention as previously described each has the passage means 33, 33A, 33B and 33C thereof formed by a plurality of vanes, it is to be understood that the various passage means could be formed by other structures as desired. For example, reference is now made to FIGS. 11 and 12 wherein another pulley of this invention is generally indicated by the reference numeral 22D and parts thereof similar to the other pulleys 22, 22A, 22B and 22C are indicated by like reference numerals followed by the reference letter "D". As illustrated in FIGS. 11 and 12, the pulley 22D comprises a conventional pulley portion 23D having a hub portion 36D adapted to be secured to a driven or driving shaft 38D in any suitable manner and has an outer peripheral groove 37D for receiving part of an endless belt 39D therein, the pulley portion 23D having substantially parallel opposed sides 34D and 35D as previously set forth. However, the pulley portion 23D is provided with a plurality of passages 33D that can be formed by drilling into the side wall 34D of the pulley 23D adjacent the hub 36D thereof at an angle so that the same will intersect with the bottom annular surface 52 of the pulley portion 23D that defines the bottom of the peripheral groove 37D thereof. In this manner, each passage 33D has an inlet 45D disposed adjacent the hub 36D of the pulley portion 23D and an outlet 46D disposed adjacent the peripheral groove 37D thereof, the passages 33D being substantially radially disposed in the pulley 23D and being substantially straight between the inlets 45D thereof and the outlets 46D thereof as well as being substantially equally spaced in a circumferential manner about the pulley portion 23D in substantially the same manner that the passages 33 are disposed equally spaced in a circumferential manner about the pulley 22 previously described. The passages 33D of the pulley 22D operate in substantially the same manner as previously described for directing a flow of air therethrough to cool the pulley 22D and, thus, the belt 39D during rotation of the pulley 22D by the aforementioned centrifugal action but additionally such air exiting the outlets 46D of the passages 33D will directly flow against the bottom surface 53 of the belt 39D to additionally cool the same in combination with the conduction cooling thereof caused by the air flow through the passages 33D. Therefore, it can be seen that the pulley 22D, in effect, is a vented hub arrangement whereas in the pulleys 22, 22A, 22B and 22C, the same are, in effect, vented sidewall arrangements. Nevertheless, in both situations, air flow is created by centrifugal acceleration of a boundary layer due to rotation and augmented by a Venturi effect as the passages are swept through the air faster at the outer outlets than their inner inlets which are near the respective hubs. In the case of the vented hub 36D of the pulley 22D, air flow cools the base of the belt and inhibits heat transfer through the base of the pulley 22D from the shaft 38D. Also, it can be seen that in the pulley 22D, the air flow into the peripheral groove 37D cools either or both pulley faces 34D and 35D and the belt 39D is additionally cooled by conduction. While the pulleys 22, 22A, 22B and 22D have been illustrated and described as having the respective ventilating passages 33, 33A, 33B and 33D on one side thereof, it is to be understood that such passages 33, 33A, 33B and 33D could be on both sides thereof by like structure or different structure as desired, such as is illustrated in FIG. 1 for the pulley 22, and in the case of the pulley 33D, the passages 33D from each side 34D and 35D thereof could be staggered relative to each other or could intersect each other, such as at the annular surface 52, as desired. Of course, a combination of passages 33D and passages 33, 33A and 33B could be provided for each pulley of this invention. Also, if desired, air flow through the passage means of any of the pulleys of this invention could be augmented by mounting an external fan or blower adjacent thereto to additionally force air into the inlets of the passage means and, thus, through the passage means. While the pulleys 22, 22A, 22B and 22C have been illustrated and described as having the inlets for the respective ventilating passages 33, 33A, 33B and 33D adjacent the respective hubs thereof while the outlets are respectively disposed adjacent the respective peripheral grooves thereof, it is to be understood that the fluid flow through the passages 33, 33A, 33B and 33D could occur in a reverse direction therethrough. For example, the pulley system could be mounted in a chamber that is supplied fluid under pressure while the hub of the pulley is vented to the atmosphere or to a chamber having a lower pressure so that the fluid will flow in opposition to the centrifugal force created by the rotating pulley from the outer periphery of the passages to the inner periphery thereof for the aforementioned cooling purposes. Therefore, while the terms "inlet" and "outlet" have been previously utilized in the specification and in the following claims to designate the openings of the passages respectively adjacent the hub and peripheral groove of the pulley, it is to be understood that the inlet for each passage means could be disposed adjacent the peripheral groove while the respective outlet thereof is disposed adjacent the hub whereby it is to be understood that in this description and in the following claims, the term "inlet" can be substituted for the word "outlet and the term "outlet" can be substituted for the word "inlet" for each of the passage means set forth herein. It is also to be understood that through suitable shaping or directing of the outlets of the passage means of the pulleys of this invention, the fluid leaving such outlets of the passage means can be directed to directly engage against the belt of the respective pulley so as to further tend to cool the same. For example, suitable shrouding can be provided either integral with the pulley or separate therefrom for directing the flow from the outlets of the passages thereof directly against the belt operating with such pulley. Therefore, it can be seen that this invention not only provides improved belt pulleys, but also this invention provides improved methods of making such belt pulleys. While the forms and methods of this invention now preferred have been illustrated and described as required by the Patent Statute, it is to be understood that other forms and method steps can be utilized and still fall within the scope of the appended claims.

A belt pulley and method of making the same are provided, the pulley having a hub and a peripheral groove for receiving part of an endless belt therein that is to drive the pulley or be driven thereby whereby the pulley is adapted to be rotated about the axis of the hub. The groove of the pulley defines an annular bottom surface of the groove and a pair of spaced apart angled inside surfaces of the groove that join with the bottom surface and diverge away from each other as the angled surfaces extend away from the bottom surface. The angled surfaces are adapted to be engaged by opposed angled sides of the belt in such a manner that a bottom of the belt will be spaced from the bottom surface. The pulley has opposed outer sides. The pulley has at least one passage provided with an inlet interrupting one of the opposed outer sides adjacent the hub and an outlet interrupting the bottom surface of the peripheral groove whereby fluid passing through the passage from the inlet to the outlet thereof will tend to cool the pulley and the belt as the pulley rotates about its axis, the passage comprises a straight bore connecting the inlet and outlet and having a centerline, the bore being arranged such that upon extension of the centerline through the outlet it will intersect one of the angled surfaces in close proximity to the bottom surface.

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to the concurrent detection of the electrical and mechanical activity of the heart by non-invasive means, the processing of the data and its presentation to physicians and other health care providers with the objectives to diagnose a condition, monitor a condition, guide a therapeutic intervention, or provide prognosis regarding some pathology. [0003] 2. Description of the Prior Art [0004] The heart is a complex pump that engineers may view as an electromechanical device. Its pumping performance varies from moment to moment or beat to beat as it reflects the dynamic and emotional state of the organism, a human or an animal, that it serves. The natural control of the heart is partly traced to the electrical activity of its tissues, which are partly influenced by the central nervous system, partly by chemical influences delivered through the blood, partly by the state of its own coronary circulation, as well as its past history, such as myocardial infarcts, occlusion of coronary arteries, trauma, and so on. The diagnosis and treatment of pathological heart function are dependent on measurements of these influences and on the hemodynamic performance of the pump. [0005] The present invention in its preferred form relates to the concurrent detection of the electrical and mechanical activity of the heart by non-invasive means, the processing of the data and its presentation to physicians and other health care providers with the objectives to diagnose a condition, monitor a condition, guide a therapeutic intervention, or provide prognosis regarding some pathology. It could also be utilized to query information from other electrically active organs. This method is suitable for non-biological applications where electromagnetic radiation and physical position are to be sensed remotely from a source or multiple sources. This, for example could be accomplished with a plurality of the Laplacian sensors and the sonar of a submarine. [0006] The performance of the human heart in health and disease has been quantitatively studied at least since William Harvey presented “De Motu Cordis” early in the 17 th century. Non-invasive means for gathering such data regarding heart parameters have been used for more than a century. These means include auscultation, listening to the sounds from the chest with a stethoscope, recording roentgenograms and cine-radiograms (early 20 th c.), electrocardiograms or ECGs (early 20 th c.), pressure recordings, impedance cardiograms (Kubicek et al., mid-20 th c.), electro-kymograms (cca. 1950), ballistocardiograms (cca. 1950), among others. Simultaneous access to localized electrical and mechanical activity has been elusive. ECGs provide considerable detail about the electrical activity of heart tissues, but very little about the heart's pumping. Body surface electrograms (BSE) and vectorcardiograms (VCG) showed great promise, but for various reasons have not become standard tools in cardiology. Ultrasonic techniques have emerged over the past two decades providing fine details about the architecture and dynamics of the heart, non-invasively. Various algorithms have evolved to quantify these aspects. Despite these advances, the simultaneous display and quantitative presentation of the electrical and mechanical activities have been inadequate, limited to a surface ECG recorded along with sophisticated ultrasonic studies, or, alternately, blood pressure monitoring during a sophisticated electrophysiologic study. [0007] ECGs and BSEs are recorded according to certain conventions. A minimal ECG system comprises three electrodes on the body surface, two of which, the “active” electrodes, are connected to a differential amplifier and the third one serves as a potential reference, usually connected to ground. Ideally, the potential difference between the two active electrodes is amplified. The record is called bipolar when the active electrodes are far apart on the chest, for instance, placed on the left and right shoulders. The record is unipolar when there is one “active” electrode that is placed at one of many specific anatomic landmarks, the V-lead positions, near the heart, while the second electrode is not really active as it is the average of the potentials at three sites, the left and right arms and the left leg; this reference is called the Wilson terminal. This mode of recording is rather sensitive to the placement of the active electrode and allows identification of parts of the heart where the electrical activity is abnormal. [0008] In BSE the number of active electrodes is large, usually ranging from 30 upward to more than 100; each one provides information about activity in its own vicinity. However, the signal is only moderately responsive to nearby electrical activity and it is often hard to distinguish local from more distant activity as the amplitude of the detected signal is proportional to the volume of contributing tissue mass and inversely proportional to its distance to the electrode. [0009] Bipolar recordings with closely spaced electrodes are more sensitive to local activities but they are also selective with respect to the direction of travel of the electrical activity in the tissues. The electrical source of the signal travels inside the body and within the heart, and may be represented by an equivalent mobile dipole. When the line connecting the surface electrodes coincides with the travelling direction of the source, then the signal is strongest, when those are perpendicular, the signal vanishes. For this and other reasons, concentric electrodes have been used at least since 1950, when Fattorusso et al. reported that supplementary information may be extracted with such electrodes. BRIEF HISTORY OF RELATED TECHNOLOGIES [0010] Around 1984, the present inventor, Peter Tarjan proposed the use of three concentric ring electrodes in a bipolar connection (+−+) to record the local electrical signals generated by the heart. (“Local,” implies the vicinity of the sensor.). Prior to 1987, those chronically implanted epicardial sensors were tested successfully in dogs to detect, acutely and chronically, artificially induced arrhythmias, for up to three month. The results were first presented in Boston (NASPE, 1987) and in Jerusalem (World Congress in Cardiac Pacing, 1987). [0011] M. Kaufer and L. Rasquinha worked on the continuation of the project at the University of Miami with Peter Tarjan. Both their M.S. theses dealt with tripolar concentric sensors, with emphasis on the sensor being in contact with the epicardium. Subsequently, the passive 3-ring sensors were tested for surface recordings from the torso, without success. Those sensors were also evaluated on the human forehead for the purpose of sensing volitional facial maneuvers. This work led to a U.S. Pat. No. 5,817,030 assigned to the University of Miami, in October 1998. [0012] A compact “active” sensor with its own batteries was developed next for surface recordings of the heart's activity using similar 3-ring sensors. Two or three concentric electrodes provide signals in proportion to the first and second spatial derivatives of the surface potential on the torso. The three electrode configuration uses the inner and outer electrodes shorted to each other to enhance spatial selectivity. [0013] A doctoral dissertation by a Mr. Chih-Cheng Lu advanced the development of the three-ring sensors. The prototypes of the sensors and the signal processing software were tested on healthy volunteers and more than 60 patients. The objective was to record the second spatial derivative of the surface potential directly from the chest. Others, especially B. He, have also obtained such surface plots by computing these derivatives from digitized surface potential maps. [0014] Set forth below is a bibliography of the prior art literature references related to heart activity monitoring and computed Laplacian electrograms. [0015] Fattorusso, V., M. Thaon, and J. Tilmant, Contribution a l'etude de l'electrocardiogramme precordial. Acta Cardiol, 1949. 4: p. 464-487. [0016] Fattorusso, V. and J. Tilmant, Exploration du champ electrique precordial a l'aide de deux electrodes circulaires, concentriques et rapprochees. Arch. Mal de Coeur, 1949. 42: p. 452-455. [0017] He, B., et al., A comparison of volume conductor effects on body surface Laplacian and potential ECGs: a model study. Computers in Biology and Medicine, 1997. 27(2): p. 117-127. [0018] He, B., Y. B. Chernyak, and R. J. Cohen, An equivalent body surface charge model representing three - dimensional bioelectrical activity. IEEE Transactions on Biomedical Engineering, 1995. 42(July): p. 637-646. [0019] He, B. and R. J. Cohen, Body surface Laplacian mapping in man. Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 1991. 13: p. 784-786. [0020] He, B. and R. J. Cohen, Body surface Laplacian ECG mapping. IEEE Transactions on Biomedical Engineering, 1992. 39(2): p. 1179-1191. [0021] He, B. and R. J. Cohen, Body surface Laplacian mapping of cardiac electrical activity. The American Journal of Cardiology, 1992. 70(December): p. 1617-1620. [0022] He, B. and R. J. Cohen, Body surface Laplacian electrocardiographic mapping - a review. Critical Reviews in Biomedical Engineering, 1995. 23(5&6): p. 475-510. [0023] He, B., et al., Body surface Laplacian mapping of cardiac excitation in intact pigs. PACE, 1993. 16(May): p. 1017-1026. [0024] He, B. and D. Wu, A bioelectric inverse imaging technique based on surface Laplacian. IEEE Transactions on Biomedical Engineering, 1997. 44(7): p. 529-538. [0025] Johnston, P. R., The potential for Laplacian maps to solve the inverse problem of electrocardiography. IEEE Transactions on Biomedical Engineering, 1996. 43(4): p. 384-393. [0026] Johnston, P. R., The Laplacian inverse problem of electrocardiography: An eccentric spheres study. IEEE Transactions on Biomedical Engineering, 1997. 44(7): p. 539-548. [0027] Oostendorp, T. F. and A. v. Oosterom, The surface Laplacian of the potential: theory and design. IEEE Transactions on Biomedical Engineering, 1996. 43(4): p. 394-405. [0028] Oosterom, A. v. and J. Strackee, Computing the lead field of electrodes with axial symmetry. Medical & Biological Engineering & Computing, 1983. 21(July): p. 473-481. [0029] Bonilla, S. J., L. Rasquinha, and P. P. Tarjan. Tripolar concentric ring electrodes for detecting forehead myoelectric potentials. in Annual International Conference of the IEEE Engineering in Medicine and Biology Society. 1995. Montreal, Que, Canada. [0030] Kaufer, M., Multi - ring sensing electrodes for arrhythmia detection and classification, in MS Thesis in Biomedical Engineering. 1992, University of Miami: Coral Gables. p. 86. [0031] Kaufer, M., L. Rasquinha, and P. P. Tarjan. Optimization of multi - ring electrode set. in Annual International Conference of the IEEE Engineering in Medicine and Biology Society. 1990. [0032] Kaufer, M., L. Rasquinha, and P. P. Tarjan. In vivo detection and classification of cardiac rhythms using concentric ring electrodes. in Annual International Conference of the IEEE Engineering in Medicine and Biology Society. 1991. [0033] Lu, C.-C., Non - invasive Laplacian ECG detection using active concentric ring sensors, in Biomedical Engineering. 1998, Miami: Coral Gables. p. 112. [0034] Lu, C.-C. An Ultra High CMRR AC Instrumentation Amplifier for Laplacian ECG Measurements. in Association for the Advancement of Medical Instrumentation. 1998. Philadelphia: AAMI. [0035] Lu, C.-C. and P. P. Tarjan. Laplacian electrocardiograms with active electrodes for arrhythmia detection. in Annual International Conference of the IEEE Engineering in Medicine and Biology Society. 1997. Chicago. [0036] Rasquinha, L., Classification of arrhythmias using specialized concentric ring electrodes, in MS Thesis in Biomedical Engineering. 1993, University of Miami: Coral Gables. p. 168. [0037] Tarjan, P. P., C. Slocum, and W. Beranek. Direction independent locally specific permanent electrodes for the identification of arrhythmias. in Annual Conv. of the North American Society for Pacing and Electrophysiology. 1987. Boston. [0038] Tarjan, P P, S M Argnani, C-C Lu and G E Antonioli: Laplacian Electrograms with Active Concentric Ring Sensors. In Proceedings: II Paziente Cardiopatico tra Pratica Clinica e Sviluppo Tecnologico, pp. 51-54. Ferrara, Italy, Jun. 26, 1998. [0039] Argnani, M S, G E Antonioli, C-C Lu, and P P Tarjan: First Clinical Results with Directly Obtained Laplacian Electrograms. Heartweb, (Internet publication), January 1999. [0040] Lu, C-C: Non - Invasive Laplacian ECG Detection Using Active Concentric Ring Sensors, Ph.D. Dissertation, University of Miami, June 1998. [0041] Besio W., C-C Lu, P P Tarjan: A Feasibility Study for Body Surface Cardiac Propagation Maps of Humans from Laplacian Moments of Activation; Electromagnetics, vol. 21, pp. 621-632, 2001. [0042] Besio, W. G.: A Study Of Laplacian Surface Maps From Moments Of Activation To Detect Cardiovascular Disease, Ph.D. Dissertation, University of Miami, May, 2002. [0043] Non-analogous methods and systems relating to measurement of heart activity are disclosed in the following non-analogous U.S. patents. Pat. No. Patentee 5,146,926 Cohen 5,797,396 Geiser et al. 5,938,597 Stratbucker 6,014,582 He 6,117,087 Kamm et al. SUMMARY OF THE INVENTION [0044] As will be described in greater detail hereinafter, applicants 3-ring sensors obtain the derivatives directly, without computation. This work led to hand-made isochronal maps of the heart's activity which appeared to provide new insights into the way the depolarization wavefronts propagate through the heart muscle. These were obtained from more than 20 sensor sites, 17 sites recorded simultaneously along with a Lead II ECG. The latter served the purpose of synchronizing the sequentially obtained sets if more than 7 sites were involved. Up to 21 sites have been obtained from a single session. More recently, one of the applicants, W. G. Besio recorded from 35 sites in a regular 5 by 7 array and further improved the density of the data by interpolation. Besio also improved the signal-to-noise ratio (SNR) of the sensors as well as the filtering algorithms and simplified the system. The SNR may be improved further by signal averaging with respect to a moving time reference, the peak of the Lead II ECG. 30 seconds of digitized data per channel have been used to improve the SNR by a factor of about 5 or 6, depending on the heart rate. The instrumentation comprised the sensors and a laptop computer that was enhanced with an analog to digital (A/D) converter and LabVIEW software, to convert the computer into a “virtual instrument” for signal processing, analysis and display. Besio further refined this system by developing new processing algorithms to define the Moment of Activation (MOA) near a sensor. The MOAs are determined with rules developed utilizing fuzzy logic or other means. The MOA corresponds to the instant when the area nearest to the sensor is depolarized. The curves (or surfaces in three dimensions) connecting simultaneous MOAs are referred to as isochrones. Laplacian potential maps, both for averaged and sequential heart beats were also generated by this system. [0045] If one relies on the active sensors' far-field discriminatory behavior, then it is possible to postulate sources near the sensor, which will produce similar signals as the naturally produced data. This appears to be realizable if the instantaneous position of the source at the MOA is along the axis of the sensor. The distance from the sensor to the epicardium, the third part of the coordinate set for the dipole, may be obtained by using ultrasound. This implies that a partially open surface image of the epicardium of the left heart may be obtained non-invasively that depicts both the electrical activity and the instantaneous positions of the sources, as applicants expect to be able to provide the spatial information as well. Such a system provides a novel and economic way for the cardiologist to obtain monitoring and diagnostic data, as well as visual guidance in the delivery of interventional therapies, such as tissue ablation. [0046] Solutions to the Inverse Problem are clinically useful and important. The “solutions” are enriched if the distances from the center of each sensor to the nearest heart tissue are known. With that information available, one can continuously update the sites of the moving sources. The invention proposes several approaches toward that goal. One preferred approach is to provide for each active Laplacian sensor to be enhanced by an ultrasonic sensor to measure the time a burst of sound travels to and from the moving surface of the heart, as shown schematically in FIG. 1. [0047] The upper panel, FIG. 1 a shows schematically the cross section of the torso with the heart. Each of the eight short parallel lines arranged on the contour of the torso represents the combination of an ultrasonic sensor with an LECG sensor, together they detect both the distance of the sensor from the heart's surface and the Laplacian potential at that point. The lower figure shows the reconstruction. The contour also needs to be determined as the sensors are tangential to the contour and the distance to a point on the heart is perpendicular to the tangent at the surface. FIG. 1 b , the lower figure, shows the reconstructed and curve matched surface as a dashed line. FIG. 1 c illustrates in two dimensions and in a very much simplified manner the display of the moving virtual surface of the heart with the projection of isochronal lines onto that surface. It is self-evident that a two dimensional rendering of a time varying three-dimensional display, or five dimensional display if time and isochronal intensity are included. Such a sketch only provides a very simple illustration of one of the goals of this invention, specifically the simultaneous presentation of spatial and depolarization information about the activity of a heart in health or disease. [0048] Assuming the velocity of ultrasound propagation to be constant in the tissues involved, a fair assumption for the ventral torso (from the front), but compromised by lung tissues for dorsal (from the back) sites, direct measurements of the exact sites of the sensors on the chest surface allow the determination of the position and distance from the center of the sensor to the heart along a line orthogonal to the plane of the sensor. A virtual heart surface is then created and updated at a reasonable rate to show the movement of the heart's surface. At each ultrasonically and LECG monitored site the dipoles may be assigned for the inverse solution to mimic time dependent charges or dipoles at those points, equivalent to moving charges or dipoles on the heart. With that information, 4-D displays of the activity become available. The result is the appearance of the activation sequence on the virtual surface of the heart. Until quite recently, such concentric electrode configurations have been used for recordings where the active organ, such as the heart, and the electrodes were in direct contact with each other. Such work with three concentric elements connected in a bipolar configuration (the outer and inner elements shorted vs the middle element) to canine hearts was reported by one of the inventors, Peter Tarjan et al. in 1987, followed by the Master's theses of Rasquinha and Kaufer at the University of Miami, in 1992 and 1993. The first recordings of the electrical activity of the heart with three concentric elements on the body surface were reported by Lu et al. in 1997. The three elements were integrated with battery-powered amplifiers and signal processing to reduce interference. These sensors exhibited considerable sensitivity to nearby events and rejected “far-field” activity. The potential difference between the terminals of such concentric electrodes with small gaps between the elements was shown to be proportional to the second spatial derivative of the surface potential, also known as the Laplacian “potential.” The dimensions of the Laplacian are in volts/m 2 , hence the quotation marks, however, the signal from the sensor is indeed a voltage that is “scaled” by the gaps between the three element. This will be shown in more detail. This method of recording may be referred to as a Laplacian ECG (LECG). Simultaneous LECG recordings from as many as 7 surface sites were obtained along with a conventional “bipolar Lead II ECG.” [0049] The limitation to seven sensors was set by the capacity of the A/D and the recording system. The number of simultaneously recorded channels may be expanded to well beyond 50. The ultimate physical limits on the number of sensors and channels are the space available to place sensors on the subject's torso and the size of each sensor as those can not overlap. The diameter of the sensor determines its depth to sense. Besio reported results with up to 35 recording sites on the human torso. (Besio: Ph.D. dissertation; University of Miami, May, 2002.) The present application arises from that work. [0050] In a related area of investigation He et al. reported their results with computing the Laplacian ECG from numerous regularly spaced unipolar sites forming an array for body surface electrograms (BSE). The Laplacian was computed from the differences in simultaneously observed potentials at adjacent electrodes. As the electrode array was typically rectangular, the computed LECGs are expected to be sensitive to the orientation of the axes of the sensors with respect to the travel of the electrical source within the heart. [0051] The “Inverse Problem” in electrocardiography may be stated as a task to define the site, nature and timing of electrical activity within the heart from surface recordings. It is generally considered a problem without a singular solution. However, approximate solutions appear to be valuable for the cardiologist in the analysis of cardiac depolarization patterns, especially in the atria whose contribution to the surface ECG is typically very modest. It is one of the objectives of this application to outline ways to obtain approximate representations of the electrical activity of the heart, displayed in space and time as follows: the LECG at a point on the chest presents the electrical activity from that part of the heart that is closest to the sensor. Other electrically active biological or non-biological sources could be processed in a similar fashion. The LECG provides a signal that is a function of time and unique at the site of observation. That site needs to be identified with respect to anatomic landmarks and the distance between the sensor and the source of the electrical activity represented by the LECG should be known. With that information continuously updated as the heart moves within the chest and the sensors move along with the chest, one may create a map of the electrical activity on the chest surface. The signal's strength is strongly dependent on the distance between the instantaneous position of the “equivalent” moving dipole in the heart and the Laplacian sensor. The signal decreases in proportion to the inverse cube of the distance between source and sensor. The signal amplitude and its spectrum depend on the dimensions of the Laplacian sensor. Sensitivity to activities deeper than the radius of the largest of the sensor's rings is nearly negligible. The spectrum is also more broad when the distance between those is small. The concentric sensors act as low pass filters whose cutoff depends on the source-to-sensor distance. [0052] Combining the signal as a function of time at each sensor's position, using multiple sites, it has been possible to create chest surface maps of isochrones and Laplacian potentials (Ph.D. dissertations of C-C Lu, 1998 and W. G. Besio, 2002). These were obtained both, by signal averaging a sequence of similar heart cycles, and for individual heart beats. Besio's dissertation demonstrated at least two special applications: the activation maps for atrial arrhythmias and for “biventricular” pacemakers. [0053] The isochrones are the curves on the chest surface which indicate the simultaneously depolarized zones. Their utility may be in detecting zones of delayed depolarization such as areas, which have suffered infarctions. The utility of such displays is in diagnosing the site and dimensions of an infarct. The display may also present valuable diagnostic data about the direction of propagation of the activity as those trajectories are orthogonal to the isochronal lines. Using a smaller number of sensors, such as seven sites, the eighth channel for a Lead II ECG allows combining LECGs recorded in sequence from the same sensors but placed in new locations, as long as it is assumed that the beat-to-beat rhythm is relatively stationary. This assumption is further justified when signal averaging is employed for each sensor to improve the signal-to-noise ratio (SNR). The trigger for the signal averaging process can be derived from a fiduciary point of the standard bipolar surface ECG, such as the peak of the “R-wave” of Lead II. The R-wave is the most pronounced feature of that signal and easy to recognize. Our prior work involved 30 to 60 second long recordings, whose SNR was improved by about a factor of 6 after averaging. [0054] Another objective of the system of the present invention is to monitor the mechanical movement of the heart within the chest in its preferred embodiment or in other embodiments, electrically active biological or non-biological sources, especially with respect to the positions of the LECG sensors. The preferred embodiment is described, but the technology could easily be applied for other applications not described or expressed. The distance between the sensor and the closest part of the heart's surface can be monitored with ultrasonic echo detecting transducers. It is assumed that the speed of sound in the tissues from the body surface to the heart is known well enough to be able to compute the distance traveled from the time the echo from the heart returns to the transducer. This assumption is quite reasonable for the frontal and left lateral portions of the heart, based on the anatomic relationship between the heart and the left lung. [0055] If the distances between a set of LECG sensors to the heart may be monitored in a nearly continuous manner, such as once every 10 ms at each site, then from the instantaneous distances from the position of each LECG sensor, one may create a virtual surface within the chest. The LECG map may then be projected onto this virtual surface, instead of being shown on the chest surface. Correction factors for the magnitude of the signal may be determined from the distance measurements to obtain the final, dynamically changing map of electrical activity on this moving virtual heart surface. Besio's dissertation demonstrated in 2002 the projection of the signals from an array on the body surface to a cylinder that was used as a substitute for the chest. A somewhat modified transformation is used for projecting the LECGs from the surface onto the virtual surface of the beating heart as obtained from ultrasonic measurements. [0056] It is understood that the virtual surface is neither closed nor highly accurate for the two main reasons that the activity of the right free wall of the right ventricle may not be determined accurately either with LECG or ultrasonic sensors; and because the speed of sound in the lungs is different from more dense tissues. These comments also apply to maps of the atria. [0057] Despite these limitations, akinetic zones, such as infarcts or old scarred zones, are expected to be shown stationary while the electrical activity is expected to be delayed and weak from those zones. [0058] Another method of generating a realistic moving surface of the heart employs Doppler phase shift measurements by each single sensor. The phase shift is proportional to the relative velocity of the reflecting surface element on the heart with respect to sensor on the torso. This velocity corresponds to movement along the normal vector from the sensor. The sequence of velocity values can be employed to predict the probable position of the reflecting surface for the next echo determination. The measurement of the distance based on the flight time of the echo provides the actual position of the reflecting element, while the corresponding phase shift provides the information to estimate the next position of the reflective element, and so on. [0059] For the surface maps, the spatial information may be obtained in a relatively simple manner by momentary breath holding to immobilize the sensors. The sensors' locations on the chest may be determined by several different means with respect to anatomic landmarks such as the midline over the breastbone or sternum and by assuming a perpendicular axis connecting the subject's nipples. Other anatomic landmarks may also be used such as certain spaces between specific ribs, etc. [0060] To obtain the virtual heart surface with respect to the sensors on the chest surface, breath holding and similar landmarks may be employed as a frame of reference. The details of this method and variations on it will be described below. [0061] According to the teachings of the present invention, a display of the electrical activity of the heart as a function of space and time for medical use by a cardiologist is developed. Such display will enable the diagnostician to see whether the electromechanical behavior of the heart is normal, and if it is not, then where and when the aberrant behavior originates and how it propagates. The electrical activity of the heart may be viewed at the cellular level as the membranes of the muscle fibers depolarize and repolarize cyclically. The activity may also be viewed as depolarization and repolarization fronts moving through the heart, separating the tissues into polarized and depolarized compartments. As depolarization penetrates the heart muscle volume as a wavefront, the polarized compartment is pushed back, behind the advancing wavefront. However, after a finite period, typically ranging between 200 and 400 ms, the depolarized region returns to the polarized or “resting” state, awaiting the next depolarization wave. Cardiac arrhythmias, such as too rapid, too slow, or irregular rates of depolarization and contraction are associated with diseases of the heart and are studied in the electrophysiology (EP) laboratory by specialists with the aim to understand the aberrant mechanisms and treat those with drugs, devices or by surgical means. The EP studies are usually invasive, that is, electrodes are introduced into the heart or its vasculature to sense local activity. The positions of the sensing electrodes are ascertained by fluoroscopy. These procedures are very time-consuming and carry a variety of risks. The longer the procedure, the greater the risk for complications. Hence, preliminary information about the propagation of depolarization in space and time, even if insufficient for a definitive diagnosis and intervention, appears to be important in saving time, allowing a preliminary diagnosis, and reducing the time spent on the invasive study. [0062] Directly Obtained Laplacian Cardiac Electrograms (DOLCE) [0063] LECG represents the second spatial derivative of the surface potential. [0064] Symbolically ∇ 2 Φ stands for this second spatial derivative of the potential. [0065] In Cartesian coordinates: ∇ 2  Φ = ∂ 2  Φ ∂ x 2 + ∂ 2  Φ ∂ y 2 + ∂ 2  Φ ∂ z 2 [0066] where Φ is the potential and it is a function of time and space, Φ(x,y,z,t). [0067] According to Poisson's equation [Guirajani: Bioelectricity and Biomagnetism, p. 197, 1998], assuming that electrical current sources exist in a volume: ∇ 2  Φ = ∇ · J σ [0068] where ∇·J represents the divergence of the current density, namely the sources that generate the current in the chest that gives rise to Φ, the potential in the chest, a volume conductor, whose conductivity is σ. In this formulation the conductivity is assumed to be homogeneous. As the current density arises from sources within the heart, in the region outside the heart that includes the surface of the chest where ∇ s 2 Φ=0 [0069] The boundary of the body (unless it is immersed in a conductive fluid, such as seawater) prevents current flow across the surface, hence J n the normal component of the current density at the surface is zero. [0070] For this reason ∇ 2  Φ = ∂ 2  Φ ∂ n 2 + ∂ 2  Φ ∂ ξ 2 + ∂ 2  Φ ∂ η 2 = 0 [0071] at the surface. [0072] The negative of the surface Laplacian in the tangential plane represents the discontinuity in normal current at the surface point (ξ,η). The value of this is made up of two orthogonal components and could be computed from the potentials at adjacent point electrodes in an array on the body surface. Instead of computing the value of the Laplacian from small differences, we have adopted a method to obtain directly the local Laplacian by placing either two, or three concentric elements at the site as shown in FIG. 2 a and FIG. 2 b and connected as shown. [0073] The Laplacian map is a two-dimensional plot of the local value of the surface Laplacian at each spatial (ξ and η) coordinate that varies with time. The time dependence arises from the heart's depolarization and repolarization, where n is a vector normal to the body surface and pointing into the body. At that point the Laplacian corresponds to the second spatial partial derivative with respect to the radial displacement in the plane tangential to the body surface at (ξ; η). BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS [0074] [0074]FIGS. 1 a , 1 b and 1 c show the method of detecting the moving surface of the heart with respect to the sensors, and the production of a virtual surface on which the concurrent electrical activity of the heart may be projected to depict kinetic and electrical activity together in a unified manner. [0075] [0075]FIGS. 2 a and 2 b show two concentric electrodes which are used to sense surface potential on a body and shows equations related to the second partial derivatives of the surface potentials. [0076] [0076]FIG. 3 is a depiction of the movement of two fuzzily defined points on the surface of a heart. DETAILED DESCRIPTION OF THE INVENTION [0077] Referring to the drawings in greater detail, FIG. 2 a , represents the core idea in Laplacian recordings. The idea is that the “Laplacian” detects the second spatial partial derivative of the surface potential on the body. It is defined in Cartesian coordinates as: ∂ 2  V  ( x , y ) ∂ x 2 + ∂ 2  V  ( x , y ) ∂ y 2 + ∂ 2  V  ( r ) ∂ r 2 [0078] where V(x,y) is the surface potential at x,y versus some reference potential, such as the right ankle. [0079] The computational method adopted by Bin He at the University of Chicago approximates this Laplacian by measuring potentials (ECG values) at specific points (x,y) on a matrix and computing the differences at a given time. [0080] Δx=Δy [0081] These small electrodes of about 2 to 5 mm diameter are placed on the chest surface. The distance, Δx, between adjacent electrodes is about 10 mm in He's setup. [0082] The computed approximate Laplacian obtained is as follows: V  ( x i + 1 , y i ) - V  ( x i , y i ) Δ     x - V  ( x i , y i ) - V  ( x i - 1 , y i ) Δ     x ∝  ∂ V  ( x , y ) ∂ x  | x = x i + Δ     x / 2  - ∂ V  ( x , y ) ∂ x  | x = x i - Δ     x / 2 ∝  ∂ 2  V  ( x , y ) ∂ x 2  | x = x i Similarly :   V  ( x i , y i + 1 ) - V  ( x i , y i ) Δ     y - V  ( x i , y i ) - V  ( x i , y i - 1 ) Δ     y ∝  ∂ V  ( x , y ) ∂ y  | y = x i + Δ     y / 2  - ∂ V  ( x , y ) ∂ y  | x = y i - Δ     y / 2 ∝  ∂ 2  V  ( x , y ) ∂ y 2  | y = y i [0083] The computed Laplacian ECG is proportional to: [ [ V  ( x i + 1 , y i ) - V  ( x i , y i ) Δ     x - V  ( x i , y i ) - V  ( x i - 1 , y i ) Δ     x ] 2 + [ V  ( x i , y i + 1 ) - V  ( x i , y i ) Δ     y - V  ( x i , y i ) - V  ( x i , y i - 1 ) Δ     y ] 2 ] [0084] The value is somewhat dependent on whether the computation is based on the differences along the x and y directions or along the diagonals of the array. They are not the same! Also, as it computes the difference between almost the same values, small errors in the digitized values at each point can produce large errors according to “the tyranny of small differences”—a derogatory term for computing—rather than measuring small differences. (It is the problem of determining whether one of two identical twins is bigger than the other. If you place them on a scale one by one against weights, the error may be larger than the difference between the babies. It is best to put the babies on a balance simultaneously to determine which way the scale tips.) [0085] In contrast, applicants use three concentric electrodes. The inner and the outer electrodes are shorted with the assumption that on a conductive electrode the potential is uniform, hence the two shorted rings would be at a given instant at the potential that represents the average potential for the areas those electrodes contact, [V a =(V outer +V inner )/2]. The average of the inner-outer pair of elements, minus the intermediate ring V i , represents the Laplacian potential. This is a very small amplitude signal as V a and V i are almost the same except when the source of the potential is in the vicinity of the sensors. FIG. 2 a shows the concentric electrodes used. [0086] As the Laplacian signal is proportional to the square of the gap, the Laplacian signal is small in amplitude even from sources in the vicinity of the sensor. On the other hand the Laplacian sensor is insensitive to interference from a source remote from the sensor. Amplification of the signal is necessary before further processing. Mr. Chih-Cheng Lu developed a self-contained amplifier and band-pass filter that was reduced to such a small size that the electronic circuits and a 2-cell lithium battery all fit on the back of the sensor. Through a miniature cable, the sensor could be interfaced with an A/D converter and the “directly,” in contrast with “computationally,” obtained LECG (or Directly Obtained Laplacian Electrogram: DOLCE) data was stored in a computer memory at the sampling rate of 1000 samples/channel/second. [0087] Lu's design provided a gain of 1000 and SNR of nearly 120 dB. Besio further improved the design by reducing the noise level, and improving the SNR. [0088] Lu's design was suited for signal averaging, using the QRS of the Lead 2 ECG. The typical recording was 30 seconds long with about 30 to 50 heartbeats. As the SNR improves with the square root of the number of events, the SNR improved by a factor of 5 to 7 when Lu's records were signal averaged. [0089] Besio's sensors are more quiet and offer more gain, hence it was possible to record and process the signals for a single beat, without signal averaging. This feature enabled Besio to obtain signals from atrial depolarizations without signal averaging. [0090] Monica Kaufer's MS thesis dealt with the optimization of the geometry of the sensor. Her work showed that the optimal size for the radius of a sensor's outer electrode is d for detecting depolarizations d distance below the surface. [0091] Based on her work, the “active” electrodes, those with their integral amplifiers and filters, were designed to be 36 mm diameter by both Lu and Besio. [0092] Lu experimented with a 2-element sensor, as shown in FIG. 2 b . That configuration yields a larger output that is proportional to the gradient of the potential, or the approximate electric field intensity at the center of the sensor. [0093] An analysis of the geometry of coordinate systems moving with respect to one another is set forth below. [0094] If S i (x i ,y i ) designates the center of the j th sensor on the torso, then z i is the distance from the center of the DOLCE sensor to the heart. That point on the heart may be designated as P i (x i , y i , z i ) where z i is the “depth” of the echo-generating site within the torso. The metric d j (t) is the instantaneous distance between S i and P i . With reference to the P i points serving as the apices of a polyhedral surface, virtual surfaces of the epicardium and the endocardium may be constructed in real time, with frequent updates of the surface. This process may include the estimated sites of the points of reflection of the echo on the surface of the heart on the basis of Doppler phase shift measurements as explained earlier. The virtual surface derived from these ultrasonic measurements will result in a distorted image as the surface of the torso is stretched into a plane to form a map. However, there are other ways, using ultrasound, to determine the positions of the echo generating tissue zones. These will also be described. The frequency of updates will be limited by such factors as the transit time for ultrasound and computational speed. The distances from the torso's surface to the heart are on the order of 10 to 100 mm, hence at the typical speed of sound in soft tissues, 1.54 mm/microsecond, the transit times are on the order of a fraction of a millisecond. [0095] It may be noted that the resolving power of ultrasound is proportional to the frequency of the ultrasonic oscillations while the depth of penetration diminishes with increasing frequency. For example, the wavelength of an 8 MHz wave is close to 0.2 mm but its penetration is limited to approximately 20 mm. If the transducer is used for probing at 40 mm, the signal becomes severely attenuated. A more traditional frequency, such as 1.5 MHz would offer lower resolution around 1 mm, but it would be suitable to probe the heart even from dorsal sites. [0096] Using software already developed, 4-D or 5-D presentations may be constructed with respect to the needs and expectations of a clinician. 4-D provides isochronal contours evolving on the virtual image of the beating heart. Five dimensions include the three spatial coordinates for each site on the heart contributing to the virtual image, along with the Laplacian potential evolving as a motion picture as a function of time. This may be visualized as if there were two separate but interlocked sensing systems operating. One of these consists of a set of sensors on the body surface collecting and processing Laplacian signals from a finite set of points confined to the body surface. The other system monitors the movements of the heart's surface and the positions of the Laplacian sensors. The data is converted into a virtual surface that moves in a coordinate system of choice, such as the frame of the laboratory or an anatomic landmark in motion, such as the xiphoid process in the chest. The LECG activity may then be projected onto the virtual image of the surface of the heart. The challenge of presenting these values is first met by constructing a 3-D virtual model of the heart for projection on a screen and use of colors to indicate the magnitudes of Laplacian potentials as they evolve and move over the heart until they are extinguished. [0097] It should be noted that in the normally beating heart depolarization precedes muscle contraction, hence during the depolarization phase, while the LECG is most pronounced, the normally beating heart is at the end of its filling phase and relatively stationary. In a slowly beating heart the “screen” for projection is stationary. However, the moving surface during the entire heart cycle would enable the physician to visualize the relationship between akinetic and active zones. At fast heart rates, tachycardias, the electrically active and mechanically active phases of the heart cycle tend to overlap more. This dual detection system would prove very useful in the study and diagnosis of such pathological cases. [0098] The method of combining the ultrasonic and Laplacian sensors offers certain advantages. The reference point for the LECG is locked to the origin of the distance measurement to the epicardial surface. However, there are other ways to obtain spatial changes. [0099] The detection of the motion of the heart is not trivial as the B-mode detectors provide displacements between two sets of fuzzily defined points as shown in FIG. 2. [0100] The vector of concern, normal to both, the surface of the sensor and the body surface (if properly applied), points from the center of a sensor along the ultrasonic beam toward the surface of the heart, where it terminates at the intercept of the beam with the heart. [0101] As both, the torso's surface and the heart's surface change with time, the surface of the heart should be described in a framework that is either referenced to the subject's stationary anatomy, such as the spinal column, the xiphoid process, or alternately, to the table. The sketch shown in FIG. 3 is exaggerated. The solid curve of the two larger ellipses represents one of the changing cross sections during the respiratory cycle of the chest, while the smaller solid ellipse represents the cross section of the heart at the same instant, t=t j . The dashed ellipses correspond to those same anatomic surfaces at a different time, t=t k . The small rectangles represent the two positions of a single sensor (S p ), which is assumed to be affixed to the chest surface and can move not only within the cross section, but even in a direction perpendicular to the cross section. [0102] As its corresponding the beam is assumed to be orthogonal to the sensor, the distance measured between the sensor's center and its beam's intercept with the epicardium, at each instant, is different. The measurement of the distance that corresponds to the length of the vector r p (t j ) yields the distance from a moving point on the chest to the moving surface of the heart, but the vector is “not stuck” on a specific moving point on the heart, it does not point to the exact same tissue element. However, that does not matter because it is the electrical activity at the point where r p points at t=t j that is of interest in the overall imaging of the electrical and mechanical aspects of heart activity. In other words, to create an exact dynamic reconstruction of the heart's surface in a stationary coordinate system, we must also know where the sensor's center is in our chosen framework (where R p (t j ) points), as well as the relationship of the sensor to its neighboring sensors. The tissue element of concern is where the vector sum of R p (t j ) and r p (t j ) points. That point may be defined by the vector in the x,y coordinate system of the table (not shown). H p ( t j )= R p ( t j )+ r p ( t j ) for t=t j , [0103] where H p (t j ) points to the intercept of the beam from the p th sensor with the heart's surface. The vector pointing from sensor p to sensor q may be described as S p,q =S p −S q [0104] which yields the inter-sensor distances on the body surface, time varying quantities. [0105] This is a classical multi-body problem that is very difficult to track precisely unless certain assumptions are made. One might assume that the motion of the thorax is negligible during quiet breathing, only the heart is in motion and being deformed continuously within the torso. [0106] If this were too restrictive then one might assume that the initial positions of the sensors on the torso are well defined within the coordinate system of the table and their positions change in a mutually dependent manner. For instance, if the distance between a pair of sensors were monitored, then the relative displacements in the positions of all the others, with respect to the initial set, will be computed as if the surface of the chest were to expand or contract as an isotropic shell. (Three points forming a triangle on the surface of the torso with sides a1, a2 and a3 will all increase proportionally. The array of the sensors may be described as an expanding and contracting 3-D surface constructed with a wire mesh of triangles.). This still allows displacement of the entire network of sensors with respect to the table! [0107] One may also choose to monitor two or more sensor locations with respect to the table as a reference and adjust the positions of the other sensors accordingly. [0108] The final task is to determine the movement and deformation of the heart's surface from the ultrasonically measured scalar values, |r p (t j )|, as a function of time, but with respect to the table's coordinate system and in reference to the instantaneous position of the corresponding sensor, R p (t j ), in the array of sensors on the chest. In other words, the following data needs to be available for each increment of time: R p ( t j )= x p ( t j ) u x +y p ( t j ) u y +z p ( t j ) u z (u is a unit vector) [0109] the orientation of the normal vector n p to the sensor's, S p 's plane at R p (t j ), [0110] the position of the intercept of the beam from S p with the heart in the table's coordinate system: R p (t j )+|r p (t j )|n p [0111] the value of the electrical activity as detected at S p . [0112] From these pieces of data, the surface of the heart and the corresponding potential distribution on it may be displayed. [0113] The distance from the sensor to the heart's surface—not necessarily a specific point in the heart's anatomy, but the shortest distance at the instant of the measurement from the sensor to the heart, is yielded by the ultrasonic B-mode distance measurements. This may be further complicated by the changing orientation of the sensor with respect to the tangent of the torso's surface at the point of attachment of the sensor. [0114] Some of these problems may be dismissed or simplified by placing the sensors on the inside of a relatively stiff garment, a vest, sufficiently inelastic to limit the movement and retain the sensors' orientation with respect to the torso's surface. [0115] Another approach may be based on a variation of the “Biosense” technique used by the invasive electrophysiology system (originated in Israel, and presently owned by Johnson & Johnson-Cordis-Webster), where the coordinates of S p may be obtained with an electromagnetic locator. (A set of mutually orthogonal RF fields is created at different frequencies. The induced voltages in the 3 added sensing coils of each sensor must be processed to determine the sensor's instantaneous location and orientation.) [0116] Another simplification of the localization of the sensors may come from using a marker on the chest and obtaining digitized images of one or two projected moiré patterns of the chest to determine the “resting positions” of the sensors automatically. [0117] As a practical starting point one may simply measure the circumference of the torso with a cloth measuring tape and the distance from the table to the sternum. With those piece of information one may simply assume that the cross section is elliptical and place the sensors along intercostal lines to prevent the ribs from obstructing the ultrasonic beam's path. [0118] While these are challenging problems, the concept of creating an approximate 3-D image of the heart defined by a polyhedron on which the electrical activity may be displayed, is viable and is useful for the practicing clinician. It is non-invasive and provides information that can only be obtained invasively at this time. Even a relatively simple and technically feasible system, such as the display of the electrical and mechanical activities in sequence, as follows, would provide a novel way for the physician to gain insight into the activity of the heart in a non-invasive manner: [0119] a. Using ultrasonic techniques, obtain a 3-D surface of the heart at the end of diastole; [0120] b. Project the electrical activity from the LECG process onto this surface as a set of isochrones. (This may be shown with contours with color-coding the time with respect to the peak of the R-wave, or as a single generic isochronal line as it moves through the surface. [0121] c. Once the isochrone disappears, the display switches to a 3-D display of the heart's surface as it changes during systole and early diastole. [0122] For comparison, one may consider the limitations of the invasive techniques in use today. The Biosense system marketed by a Johnson&Johnson subsidiary, comprises a combined electromagnetic position and electrical activity sensor at the tip of a catheter that is guided into one of the heart's cavities, the right atrium, for instance. While the tip is maneuvered and the sensed electrical activity through its tip is monitored, the physician decides when the position of the sensor should be read out. At that instant the position is read out of the sensor (with respect to the table used for the procedure as the field's generators are attached to the table) and stored as a point on the endocardium along with the electrogram, using a feature of the surface ECG as a time reference, such as the peak of the R wave in Lead II. [0123] This process is then repeated many times ranging from 25 points to as many as several hundreds of points. While the tip's position is known accurately within the framework of the table, the heart and the torso are in constant motion. Therefore the polyhedron created from those points in the heart is likely to be a distorted image of the actual cavity. This error is acceptable as long as the physician is able to guide the tip back to any desired point with moderate effort. [0124] It is thus evident that the non-invasive system disclosed is not to be compared with an idealized, accurate invasive system that is enhanced by X-ray images as well, as such systems do not exist. Invasive systems carry their own inaccuracies due to moving coordinate systems. (The electrodes move with the heart, but the heart moves within the chest and the chest moves with respect to the reference framework, the room or the table.) [0125] One added complication for the non-invasive system is that the ultrasonic sensors need to face only soft tissues toward the heart, i.e., the sensors must be placed over the gaps between adjacent ribs, or in places where the rib cage does not interfere with the view of each ultrasonic beam. Such places exist in the armpit and sub-costally, pointing toward the head. [0126] A 3-D phased array in the auxiliary region is one solution, where a relatively full and for the purpose, entirely adequate view of the heart may be obtained within the thoracic cage. That array may also be used for determining the changing positions and orientations of the sensors mounted on the chest surface. [0127] To summarize: with a supine subject, resting and quietly breathing, the torso with the sensors mounted on it may be considered stationary and the contour of the chest's cross section elliptical with the perimeter and minor axis defining those as well as the normal vectors to the chest. The scalar measures of the sensor-heart distances may then be used as obtained, uncorrected, to create the contour surface of the epicardium, a virtual beating heart, on which the MOA maps are displayed. [0128] Range of Applications [0129] The system and method of the present invention finds utility in guiding the operator, a physician, in the placement of an invasive catheter's active electrode(s) to the site of action, for instance, for cardiac tissue ablation. [0130] The system is expected to find applications in pediatric cardiology and neonatology for which the directly observed Laplacian technique seems especially appropriate. [0131] The effects of certain antiarrhythmic drugs may be monitored with a pair or more of sensors to measure delays in MOA's as a manifestation of the drug's effect. [0132] Besio's dissertation showed that the sensors do respond to atrial activity and may be used to depict atrial activity. This may enable simplifications in the non-invasive diagnosis of atrial arrhythmias, especially in combination with monitoring the atrial wall motion as a way of strengthening the validity of the detection of atrial depolarizations. [0133] Initially applicants explored tripolar concentric sensors for use in the detection of ventricular arrhythmias and fibrillation using sensors sewed to the epicardium and making the decisions for electrical interventions on the basis of triangulation. This method may be used with surface electrodes for the determination whether to defibrillate or not. This may meet the requirements for an Automatic External Defibrillator, such as the ones used at airports and sport stadiums. Triangulation may be used with surface electrodes for the determination whether to defibrillate or not. It may also be used to quantitate the level of ischemia preceding or following an infarct and monitoring the progress with clot resolving agents. This tool is likely to be proven more reliable when combined with the monitoring of wall motion. The absence of ventricular wall motion confirms the diagnosis of VF from electrical signals. [0134] Noninvasive detection of atrial activity will simplify the analysis of ECG data from ambulatory monitoring that relies entirely on ventricular signals. [0135] Ultrasonic Techniques for a 3-D Image [0136] There are several ways of using the positions of the active sensors on the chest surface. In each case the distances from the center to the nearest moving surfaces of the heart, the epicardial surface (or the pericardial sac) and the endocardial surface are measured with ultrasound: [0137] One may assume that the body is stationary during the recording and respiration only plays a secondary role in altering the sites of the sensors. In this case, using some anatomic landmarks (for instance, the midsternal line as one axis and the line connecting the subject's nipples as a perpendicular axis) one can measure the sites of the sensors with a flexible ruler within roughly ±5 mm accuracy. The topographic information may be used as a flat map, with the understanding that there will be distortions due to lack of axial symmetry and variations in the cross-section of the thorax in the region of interest, with respect to the long axis of the body. This method was used for applicants “hand-crafted” activation maps. [0138] One may affix the sensors to the inside surface of a relatively stiff, vest, “binder” or corset. In effect, that will force the subject to use only the diaphragm for respiration. This will force the thorax to follow a form forced on it and may be unacceptable for many subjects, especially those with respiratory difficulties. The predetermined positions of the sensors on the stiff binder will provide the sites on the surface with respect to some anatomic landmarks, such as the midsternal line and another one along the long axis, such as an anatomic landmark used for tracheostomy, the highest point on the sternum, or some clavicular landmark. [0139] One or more scanning ultrasonic “master” sensors may be utilized to determine the site of each active LECG sensor on the unconstrained three-dimensional surface of the chest. That information, S p (x,y,z,t) for the p th sensor, along with the orientation of that sensor and the distances d p,epi (t) (=|r p (t)|) and d i,endo (t) (referring to the echo from the inside wall) will yield spatial data to generate two open polyhedra that approximate the epicardial and endocardial surfaces of the heart as it beats. This approach will permit the display of the changing wall thickness of the beating heart, with the electrical activity spreading on the outer surface. [0140] Each active sensor may include an ultrasonic gauge that receives echoes not only from the soft tissue interfaces but also from 2 or preferably 3 landmarks attached to the thorax. Thus each sensor will provide its own position within a stationary frame of reference and the positions of the nearest epicardial and endocardial points on the heart. Again, a time dependent, pulsating, open polyhedron may be formed as a surrogate surface for each, the endocardium and epicardium of the heart, with the LECG (DOLCE) data shown either as Laplacian potentials, isopotentials or compressed into a temporally averaged surface with the isochrones displayed on that. [0141] The electromagnetic or magnetic field based position detection system in use in fighter aircraft and in medical applications may be adapted, as described earlier, to locate each sensor and its tilt within the frame of the room, rather than some anatomic landmark. [0142] Another possible method for gaining information about sensor locations could be comprised of an array of elastomer straps whose resistance varies proportionally to the amount they are stretched. As the persons body distorts from breathing or other movements, this information would be captured by this array and used to update information about where the sensors are at a particular moment. [0143] The accuracy of the image of the surface of the heart may further be enhanced by incorporating Doppler sensors for each, or even for some of the ultrasonic sensors. The Doppler technique, based on a shift in the frequency of the returning pulse from the emitted one provides the velocity of the reflecting element along the line of the beam. If the element is moving toward the sensor, the frequency shift is positive. These shifts are proportional to the velocity, hence the system could be enhanced by a predictive feature by extrapolating from the instantaneous position and velocity data where the next position would be expected. Such techniques are well established in Doppler flow systems. [0144] Displaying the Information [0145] The 4-D or 5-D presentations must be constructed in the best possible way to fit the needs of a clinician. These five dimensions include the three coordinates for each apex on the polyhedron along with the potential as a function of time. Presentation of these values requires a 3-D model projected on a monitor's screen, or preferably a holographic display, using gray scales or colors to indicate potentials and using an animated model of the heart, in essence: a motion picture, to show the spread of depolarization with time directly on the virtual surface of the heart. [0146] In summary, the 3-D image of the moving surfaces of the heart may be implemented at various levels of technical sophistication, resulting in different levels of accuracy and cost. The common feature of these approaches may be summarized as follows: [0147] The electrical activity of the heart may be tracked simultaneously on a virtual surface that represents the beating heart within the intact chest. This type of presentation of the electromechanical activity of the heart has not been available to cardiologists either non-invasively, or in real time. [0148] The currently available Biosense system and its competitors gather spatial and electrical data invasively, using a temporary lead within the heart. [0149] The polyhedral representation evolves stepwise and slowly, although the number of points is virtually unlimited. [0150] The risk of complications tends to increase in proportion to the length of an invasive process. [0151] Also, the polyhedron produced is static, it does not change with the deformations and movements of the beating heart. [0152] The technical problems of generating the virtual surfaces of the heart and the display of the electrical activity have been worked out in rudimentary form. [0153] Fast computing techniques will have to be employed to achieve cinematic quality with high resolution. However, the novel concept represents the foundation arising from the merging of electrical and ultrasonic signal processing technologies. [0154] Other Application [0155] In addition to noninvasive diagnostic applications, applicants foresee invasive applications as well. [0156] In the noninvasive category detection of atrial activity during atrial flutter and fibrillation are useful. [0157] The organization of contractions may be studied in relation to the sequence of depolarizations. This appears to be suited for the estimation of the size of an infarct. [0158] With an interventional catheter placed in the heart or in a coronary vessel, such as a balloon angioplasty catheter, non-invasive monitoring of the regional activity in the zone subjected to treatment may serve an important role to compare electromechanical activity before and after angioplasty. Fluoroscopy does provide a projection of the moving heart but information about the level of electrical viability is missing. [0159] One may envision electrical ablation to be performed without the need for multiple leads in the heart which are used for spatial and temporal references. [0160] Three or four broad technical issues can be addressed: [0161] 1. The optimal way to obtain information about the instantaneous shape and position of the heart? [0162] 2. Where to place the sensors? [0163] 3. The cardiac conditions and applications of the greatest interest to cardiologists and how to provide that information in a friendly and informative graphic display? [0164] 4. Finally, the optimal level of automatic or “expert” interpretation that will allow rapid acceptance of the instrumentation with minimal retraining of the physicians, nurses and emergency care providers. [0165] From the foregoing description, It will be understood that the method system and apparatus of the present invention have a number of advantages, some of which have been described herein and others of which are inherent in the invention. [0166] For example, the method and system enable one to determine in a non-invasive manner, the general location of a site of cardiac activity one is looking for in the heart for any desired purpose, such as locating a point in the heart for ablating tissue. [0167] Also it will be understood that modifications can be made to the method, system and apparatus of the present invention without departing from the teachings of the invention. Accordingly the scope of the invention is only to be limited as necessitated by the accompanying claims.

The method for collecting cardiac activity data non-invasively from the chest or thorax of a patient comprises the steps of: placing at least three active Laplacian ECG sensors at locations on the chest or thorax of the patient; placing at least one ultrasonic sensor on the thorax where there is no underlying bone structure, only tissue, and where the ultrasonic sensor can transduce signals directly from the heart for measuring the time a burst of sound travels to and from the moving surface of the heart; assuming the velocity of ultrasound propagation to be constant in the tissues involved; making direct measurements of the exact sites of the sensors on the chest surface to determine the position and distance from the center of the sensor to the heart along a line orthogonal to the plane of the sensor to create a virtual heart surface; updating the measurements at a reasonable rate to show the movement of the heart's surface; monitoring at each ultrasonic sensor site and each Laplacian ECG sensor site the position and movement of the heart and the depolarization wave-fronts in their vicinity; treating those depolarization wave-fronts as moving dipoles at those sites to mimic time dependent charges or dipoles at those sites, equivalent to moving charges or dipoles on the heart; and, displaying the heart activity like a moving picture which is equivalent to an approximation of the activation sequence on the virtual surface of the heart, thereby to create chest surface maps of isochrones and the projections of those of isochrones onto a virtual surface that represents the heart, which can indicate the simultaneously depolarized zones for detecting zones of delayed depolarization, such as areas which have suffered infarctions and correlating those delayed zones with the movement and shape of the heart, or thereby to create Laplacian isopotential maps either on the chest surface or their projection onto a virtual heart surface.

CROSS REFERENCE TO RELATED APPLICATION [0001] The present application claims the benefit of U.S. Provisional Appln. No. 60/753,643 filed on Dec. 23, 2005. The content of the aforementioned application is fully incorporated by reference herein. FIELD OF THE INVENTION [0002] The invention pertains to imaging and non-imaging spectrometers. BACKGROUND OF THE INVENTION [0003] Spectroscopy is a scientific technique by which electromagnetic radiation from a given source is broken down into its wavelength components and those components are analyzed to determine physical properties of the source of that radiation. Particularly, the wavelengths of radiation that are (or are not) in the spectrum are indicative of the atoms or molecules that are in the source of the radiation. Spectrometers spread radiation out into its wavelength components, creating spectra. [0004] Within these spectra, one can study emission and/or absorption lines, which are the fingerprints of atoms and molecules. Every atomic element in the periodic table of elements has a unique spacing of electron orbits and, therefore, can emit or absorb only certain energies or wavelengths. Thus, the location and spacing of spectral lines is unique for each atom and, therefore, enables scientists to determine what types of atoms are within a radiation source from its unique signature spectrum. [0005] There are three types of spectra that an object can emit, namely, emission, absorption, and continuous spectra. [0006] An emission line occurs when an electron drops down to a lower orbit around the nucleus of an atom and loses energy, thereby radiating electromagnetic waves at a particular frequency (i.e., a line of relatively intense radiation in the overall wavelength spectrum being observed). Thus, for instance, an emission spectra occurs when the atoms and molecules in a hot gas emit extra radiation at certain wavelengths, causing bright lines to appear in its spectra. The pattern of these lines is unique for each element. The position of these lines in the spectra can be used to determine the composition, temperature, density, and/or other physical properties of the object. [0007] An absorption line, on the other hand, occurs when electrons move to a higher orbit by absorbing energy. If one shines a source of radiation on an object, it will absorb that radiation only at certain very specific frequencies, depending on the atoms that make up that object. Thus, as with emission spectra, by measuring the absorption spectrum of the radiation reflected from that object, one can determine the composition of the object by determining what wavelengths that appeared in the illumination source do not appear in the reflection. This is the absorption spectra. [0008] Spectroscopy based on atomic spectral lines is primarily appropriate for visible wavelengths. In the near infrared (IR) range (which is roughly 0.75-3.0 microns), midwave IR range (about 3.0-8.0 microns), and longwave IR range (about 8.0-30 microns], the dominant mechanism responsible for spectral absorption bands are not transitions between electronic energy levels, but rather transitions between molecular vibrational energy levels. In the far IR range, sometimes referred to as the Terahertz or THz range (about 30-1000 microns), molecular rotational energy levels are the dominant mechanism. [0009] There is an additional application that pertains only to THz (far IR), namely, detection and identification of solid materials based on the absorption spectra of the material's crystalline lattice vibrations (so called phonon spectrum), which lie mostly at far IR wavelengths (THz frequencies). The principle is the same, but the fundamental mechanism for spectral emissions is lattice vibrations rather than molecular vibrations or rotations. This is useful for detecting explosives, drugs, etc. [0010] Not only can an object's composition be determined from its spectrum, but potentially also its temperature, density, and other properties, since changes in at least temperature and density can shift the signature spectral lines of an atom. [0011] Continuous spectra (also called a thermal spectra) are emitted by any object that radiates heat, i.e., has a temperature above absolute zero. The light (or other electromagnetic radiation) is spread out into a continuous band with every wavelength having some amount of radiation. Accordingly, the magnitude of radiation at a given wavelength or wavelengths may be used to determine the general composition of an object and/or its temperature or density. The continuous spectra of objects, however, generally tend to provide less information than the more specific emission or absorption spectra. [0012] Accordingly, spectroscopy and spectrometers have powerful important applications across many fields of science and technology. For example, spectroscopy and spectrometers are used extensively in astronomy to determine the composition of stars and other objects in space. Spectroscopy and spectrometers also are used in military and security applications, such as in the identification of substances that might be inside of buildings, underground, or otherwise not directly observable. Spectrometers also can be used to scan persons and luggage (at airports, for instance) to determine if the person is carrying (or the luggage contains) certain types of items, such as plastic explosives or metal objects, such as firearms. [0013] A non-imaging spectrometer observes the spectral components of all the radiation from a given source as a single unit. On the other hand, an imaging spectrometer separately detects the radiation from different points in a given field of view and determines the spectral components for each of those points separately (i.e., pixelation). Thus, for instance, a non-imaging spectrometer may employ a single photodetector for detecting the radiation from an object, whereas an imaging spectrometer would comprise an array of photodetectors, each receiving radiation from a different portion or point within the overall field of view being observed. [0014] Various techniques are known for breaking radiation into its spectral components. Perhaps the most well-known example of this is passing sunlight through a prism. Another example, is a Michelson spectrometer, in which radiation is passed through a beam splitter in order to split it into two separate beams having the same properties and then causing those two separate beams to be recombined after they travel over paths of different lengths. Because of the different lengths of the two paths, the radiation from one beam will be phase shifted relative to the radiation from the other beam, thus causing an interference pattern when the two beams are recombined. The interference pattern can be analyzed to determine the spectral components of the original single beam. An instrument that causes interference between two radiation beams is called an interferometer. [0015] Another interferometric technique for splitting radiation into two components with different phase delays and then recombining them is a lamellar grating interferometer. The lamellar grating interferometer was first described by John Strong, Journal of Optical Society of America, Vol. 57, pp. 354-7 (1957). A summary of the operation and design issues of a lamellar grating interferometer can be found in chapter fifteen of the book Introductory Fourier Transform Spectroscopy (Academic Press, New York, 1972) by Robert John Bell. Furthermore, Omar Manzado et al., “Miniature lamellar grating interferometer based on silicon technology”. Optics Letters, Vol. 29, No. 13, Jul. 1, 2004, pp. 1437-9, incorporated herein by reference, discloses a lamellar grating interferometer fabricated using MEMS (micro-electro-mechanical systems) technology for use at near infrared wavelengths. [0016] It is an object of the present invention to provide an improved spectrometer. [0017] It is another object of the present invention to provide a spectrometer with application in the near infrared to far infrared (Terahertz frequencies) wavelength spectrum in smaller sub-bands. SUMMARY OF THE INVENTION [0018] In accordance with the principles of the invention, a lamellar grating interferometer breaks the radiation down into its wavelength components. The two sets of teeth of the grating are moved relative to each other. The spectral output of the interferometer is focused on an array of detectors and data is stored for a large number of relative displacements of the grating teeth. The collected data is then Fourier transformed to recover the spectrum of the radiation. [0019] In a preferred embodiment of the invention, the detector array comprises an uncooled, microbridge detector array. In another preferred embodiment, the detector array comprises solid-state photodetectors. In yet another preferred embodiment, the detector array comprises semiconductor MEMS devices. [0020] Recent advances in micro electro mechanical system technology (MEMS) enable the fabrication of dynamically programmable lamellar gratings. A MEMS lamellar grating combined with an uncooled microbridge detector array permits the fabrication of an extremely compact and lightweight spectrometer in accordance with the principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS [0021] FIG. 1 is a schematic diagram of a spectrometer in accordance with the principles of the present invention. [0022] FIG. 2 is a more detailed schematic view of the lamellar grating interferometer of FIG. 1 . [0023] FIGS. 3A-3D comprise four spectral analyses illustrating measured and predicted spectra at terahertz frequencies of common chemical compounds used in explosives showing the unique spectral “fingerprints” which can be measured with a spectrometer. [0024] FIG. 4 is a schematic diagram of an alternative embodiment of a spectrometer in accordance with the principles of the present invention. [0025] FIGS. 5A-5C are perspective views of an exemplary implementation of a lamellar grating interferometer for a Terahertz frequency application of the present invention. [0026] FIG. 6 illustrates an exemplary imaging optical system suitable for use with uncooled detectors showing one possible approach for incorporating a lamellar grating interferometer in the system. DETAILED DESCRIPTION OF THE INVENTION [0027] The invention is a spectrometer that has application in the near infrared to far infrared (or THz) wavelength range. As a practical matter, a particular spectrometer constructed in accordance with the principles of the present invention would probably have a frequency range encompassing only a portion of the near infrared to Terahertz wavelength range; the more important point being that one can employ the principles of the present invention to produce a spectrometer that operates in a sub-band anywhere within the near infrared to Terahertz frequency range. In the prior art, the type of spectrometer and the technology used within it typically had to be vastly different depending on the particular wavelength range over which the spectrometer was to operate. In accordance with the principles of the present invention, the same basic technology and techniques can be used to create spectrometers that operate in a frequency band anywhere from near infrared (approximately 0.75-3.0 microns), through mid-wave infrared (approximately 3.0-8.0 microns) and long-wave infrared (approximately 8.0-30 microns), to far infrared (THz) (approximately 30-1000 microns). [0028] FIG. 1 is a schematic diagram of the basic components of a Terahertz range two-dimensional imaging Fourier transform spectrometer 101 in accordance with the principles of the present invention. This type of system may have application in airport security for scanning persons or luggage for explosives, firearms, and other contraband items. An illumination source 112 illuminates an object or scene 114 (hereinafter generically “object”) the composition of which it is desired to know. The object may be a piece of luggage, a person, and/or a portion of a factory. As a practical matter, the luggage or person probably would have to be positioned in a particular location in which they could be illuminated by the radiation source 112 , such as a booth or similar closed space. The illumination source 112 should emit radiation containing a given distribution of radiation at all frequencies within the bandwidth of the spectrometer. However, this is not a requirement of the system. [0029] With the active illumination source 112 , the object will absorb radiation from source 112 and thus modify the spectrum of the reflected radiation and modify the structure of the radiation reflected by the object. As previously noted, the object will have a particular absorption spectrum based on the atoms and molecules that make up that object. The radiation from the illumination source 112 that is reflected off of the object 114 is collected by an optical system 116 and brought to bear upon a lamellar grating interferometer 118 . The optical system 116 can be a conventional reflective, refractive, or catadioptric design. [0030] FIG. 2 is a more detailed schematic diagram of a lamellar grating interferometer in accordance with the principles of the present invention that may be used in the spectrometer 101 of FIG. 1 . As shown, the grating 118 comprises a first set of teeth 210 and a second set of teeth 212 . The front facets 210 a of teeth 210 are all positioned evenly with each other in the same plane. The front facets 212 a of teeth 212 are all positioned evenly with each other in the same plane. The second set of teeth 212 are movable in unison in the z direction relative to the first set of teeth 210 by a meso-scale actuator 214 so as to change the linear distance in the z direction between the front facets 210 a of teeth 210 and the front facets 212 a of teeth 212 . In the terminology of the present specification, Δz indicates the linear offset between the front facets of the two sets of teeth. Also in the terminology of the present specification, the zero offset position is the position in which the front facets of both sets of teeth are perfectly even with each other. [0031] This type of lamellar grating can readily be manufactured using well-known MEMS technology. [0032] The optical system 116 directs the radiation 211 a on the front facets 210 a , 212 a of the teeth of the lamellar grating 118 . When the teeth are in the zero offset position, the lamellar grating is essentially a mirror. However, when the two sets of teeth 210 , 212 are not perfectly even, reflecting radiation off of the font facets of the two sets of teeth's splits the radiation into two components, i.e., the radiation 211 b that has reflected off of the front facets 210 a of the first set of teeth 210 and the radiation that has reflected off of the front facets 212 a of the second set of teeth 212 . The radiation in the two different components, of course, are phase offset from each other. [0033] Referring back to FIG. 1 , the amount of phase offset depends on the distance Δz. The radiation reflected off of the front facets of the two sets of teeth is focused by a second optical system 120 onto a detection system 122 . [0034] The detection system 122 can be any system reasonably adapted to detect radiation in the frequency spectrum of the particular spectrometer. In an imaging spectrometer, the detector may comprise an array of detectors. It may be a two-dimensional array of detectors (for example, a grid of 100×100 photodetectors) or a one-dimensional array that is scanned over a field of view. Alternately, a fixed one-dimensional array of detectors can be employed and the object passed transversely through the field of view of the one-dimensional I detector array. Finally, the detection system may comprise only a single detector that is scanned to produce an image. [0035] Of course, a single detector that is not scanned can be used in a simple non-imaging spectrometer. [0036] The particular technology most suitable for fabricating the detector(s) likely will depend on the frequency range of the spectrometer, different technologies being more economically suited to different size wavelengths of radiation. In the Terahertz range, an uncooled thermal detector, such as a thermoelectric (TE) microbridge detector would be an excellent choice as a detector. Such microbridge detectors can be manufactured using MEMS technology. Some particular TE microbridge detectors that would work well in the present invention are disclosed in U.S. Pat. Nos. 5,220,188, 5,220,189, 5,449,910, and 6,036,872, owned by the same assignee as the present patent application. In the near infrared frequency range, the detector or detector array might comprise photoelectric detectors using either the photoconductive effect or photovoltaic effect. U.S. Pat. No. 5,220,188 discloses a basic etch-pit type of microbolometer IR detector. U.S. Pat. No. 5,220,189 discloses a basic thermoelectric (TE) type IR detector, which would be preferred for the present application. Subsequent improvements to these designs are described in, for instance, U.S. Pat. Nos. 5,449,910, 5,534,111, 5,895,233, and 6,036,872. [0037] In any event, the detector(s) convert the radiation signals into electrical signals, which are fed into a processing unit 224 for processing, storage, and analysis. [0038] In operation, the two sets of teeth 210 and 212 of the lamellar grating interferometer 118 are scanned relative to each other to a plurality of different Δz positions, possibly including Δz=0. At each of the Δz positions, the processor 124 receives and stores the data from the detector array 122 . After a full scan of all desired Δz positions has been conducted and the collected data stored, the processor 124 performs a Fourier transform on the data set from each pixel and determines the spectral data for each pixel of the array. This procedure is well known in the art of Fourier transform spectroscopy, as described for example in the book Introductory Fourier Transform Spectroscopy (Academic Press, New York, 1972) by Robert John Bell. [0039] FIG. 5A is an exploded view of an exemplary lamellar grating interferometer that can be used in a Terahertz frequency application of the present invention. FIGS. 5B and 5C show the same interferometer in its assembled form with the two sets of teeth at opposite extremes of their relative travel range, respectively. A similar structure can be used at other spectral wavebands of interest by scaling the grating period and other physical parameters appropriately to the wavelength. [0040] The two sets of teeth 210 and 212 are disposed on separate substrate 501 and 502 , respectively. One of the substrates 501 is mounted on a motor-actuated arm 505 that can move the substrate in the longitudinal direction of the arm so as to alter the longitudinal distance between the front faces of the two sets of teeth. The other substrate 502 is fixedly mounted to a transverse support member 507 via spacers 509 and suitable attachment means, such as screws or bolts (not shown). Additionally, springs 512 are mounted in hollow cylinders 514 that run between the two substrates 501 and 502 in order to bias the two substrates apart from each other. Finally, alignment guides 515 pass through holes in the edges of the two substrates 501 , 502 to help maintain the alignment of the two substrates both longitudinally (i.e., to keep the two substrates parallel with each other) and transversely (to keep the two sets of teeth aligned so that one set of teeth passes through the gaps in the other set of teeth without interference. As shown, the two substrates are aligned so that the teeth 210 of substrate 501 can pass through the gaps between the teeth 212 in substrate 502 . The motor actuated arm 505 can be used to change the relative distance between the two substrates 501 , 502 and thus the relative distance between the front faces of the two sets of teeth 210 , 212 . FIG. 5B shows the condition of the lamellar grating interferometer with the arm fully extended to the maximum positive ΔZ position. FIG. 5C shows the condition of the interferometer with the arm fully withdrawn to its maximum negative ΔZ position. [0041] FIG. 6 illustrates one exemplary imaging optical system suitable for use with uncooled detectors showing one possible approach for incorporating a lamellar grating interferometer in the system. In the illustrated system, the incoming radiation is reflected off of two lamellar grating interferometers 601 a and 601 b towards a focusing mirror 603 . The radiation is reflected off of the mirror 603 into the uncooled detector array 605 . [0042] How the spectral image obtained by the detector array is then further analyzed (either in the processor 124 or in subsequent processing equipment (not shown)) depends on the particular application. Merely as an example, if the spectrometer is being used as an airport security system for scanning individuals for prohibited items, then the data might be analyzed to determine if a person has plastic explosives, metal, or poisonous gas on his or her person. This would be done by analyzing the emission and/or absorption line spectral image of the person for the signature spectral image of the atoms or molecules making up such substances. [0043] Examples of spectra of typical explosive compounds at THz frequencies are illustrated in FIGS. 3A-3D . FIG. 3A shows the spectra for TNT. FIG. 3B shows the spectra for RDX. FIG. 3C shows the spectra for HMX. FIG. 3D shows the spectra for 2 , 4 -DNT. [0044] The spectrometer of FIG. 1 also can be used to obtain broadband, nonspectral images of objects, either using the illumination source 112 or simply using the ambient light and other radiation in the vicinity of the spectrometer 101 . [0045] In one preferred embodiment of the invention, the spectrometer may first be used to obtain and analyze a broadband image of a person or object data. (For a broadband image, the teeth of the lamellar grating would be set to Δz=0). Then, if any portion of the image (i.e., any portion of the individual under observation) appears to have an unusual broadband reading, then only that portion of the image can be analyzed for its absorption and/or emission spectrum by subsequently scanning the lamellar grating interferometer. Merely as an example, radiation in the wavelength range of about 0.1 to 0.3 mm is able to permeate about a millimeter of clothing and differentiate between the broadband reflectivity of human skin, on the one hand, and metal or plastic explosives, on the other hand. Thus, for instance, if the broadband image reveals that a person is concealing an object under his shirt, then that portion of the image can then be re-processed to obtain the more complex and detailed emission and/or absorption spectra and to determine the composition of that object. [0046] With current technology and assuming pragmatic parameters such as a 100×100 detector, with 300 micron pixel size providing a spatial resolution of 1.75 cm 2 at about 10 meters, for instance, a commercially reasonably priced spectrometer for the airport security market might be able to obtain a broadband image every 1/30 th of a second. On the other hand, an emission or absorption spectral image of the same size and assuming approximately 128 frequency bands might require on the order of four to five seconds per image. [0047] FIG. 4 illustrates an alternative embodiment of the invention. This embodiment of the invention is essentially identical to the embodiment of FIG. 1 except for the omission of the illumination source 112 . This embodiment uses only passive illumination (the ambient light and other radiation). This embodiment, while not preclusive of performing emission and/or absorption spectral analysis, is most suitable for broadband imaging. A spectrometer with no illumination source employing the principles of the present invention could be used practically as a stand-off continuous spectrum spectrometer with a range of about 100 to 1000 meters, depending on the specific spectral band. [0048] As a practical matter, any given spectrometer created in accordance with the principles of the present invention will operate only in a small portion of the near infrared to Terahertz range. A practical frequency bandwidth of any given implementation would likely cover a bandwidth no greater than about ½λ o to about 1.5 λ o , where λ o is the center wavelength of the band. [0049] Having thus described a few particular embodiments of the invention, various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications and improvements as are made obvious by this disclosure are intended to be part of this description though not expressly stated herein, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description is by way of example only, and not limiting. The invention is limited only as defined in the following claims and equivalents thereto.

In accordance with the principles of the invention, a lamellar grating interferometer breaks the radiation down into its wavelength components. The two sets of teeth of the grating are moved relative to each other. The spectral output of the interferometer is focused on an array of detectors and data is stored for a large number of positions of the grating teeth. The collected data is then Fourier transformed to recover the spectrum of the radiation.

RELATED APPLICATION DATA [0001] The present patent is related to co-pending U.S. Provisional patent application Serial No. 60/329,418, which was filed on Oct. 15, 2001. FIELD OF THE INVENTION [0002] The invention is generally related to dolls, and more particularly to a soft posable doll with a circular body. BACKGROUND OF THE INVENTION [0003] Dolls and other toy objects have been known for thousands of years and can take on many different forms, configurations, and constructions. Many of these objects, such as stuffed dolls and toys including teddy bears, are intended essentially for children and are known to have a soft feel and structure. These types of dolls are stuffed with a resilient filler material or stuffing and are sewn to a particular shape. Dolls and toys often include limbs extending from a body. In some instances, the limbs simply hang freely or limp from the body. In other instances, the limbs are sewn in a fixed position extending from the body. When the limbs or the body are manually moved or reoriented, they will return to their original shape and position upon release. [0004] Posable toy action figures are also known. One type of posable figure has a rubber or plastic exterior material layer with a posable internal skeleton structure embedded within the exterior layer. When the body or a limb of the figure is moved to an alternate position or shape, the position or shape is retained by the skeleton structure until further manual reorientation. BRIEF DESCRIPTION OF THE DRAWINGS [0005] Exemplary dolls in accordance with the teachings of the present invention are described and explained in greater detail below with the aid of the drawing figures in which: [0006] [0006]FIG. 1 is a perspective view of one example of a posable doll constructed in accordance with the teachings of the present invention. [0007] [0007]FIG. 2 is a front view of the posable doll substantially similar to the doll shown in FIG. 1, but having various stylistic differences. [0008] [0008]FIGS. 3 and 4 are front views of posable dolls substantially similar to the doll shown in FIG. 1, but having alternative stylistic differences and having arms positioned in different physical orientations. [0009] [0009]FIG. 5 is a front view of a posable doll substantially similar to the doll shown in FIG. 1, but having alternative stylistic differences and having the legs positioned in a different orientation and showing a wire skeleton structure in phantom view. [0010] [0010]FIG. 6 is a cross section of a posable doll substantially similar to that shown in FIG. 5 and taken along line VI-VI shown therein. [0011] [0011]FIG. 7 is a full side view of the posable doll shown in FIG. 6. [0012] [0012]FIGS. 8 and 9 are front views of a portion of the doll shown in FIG. 1 and illustrating other alternative posable hair styles. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0013] Referring now to the drawings, FIGS. 1 - 9 illustrate various examples of a soft, posable doll 20 constructed in accordance with the teachings of the present invention. As shown in FIG. 1, the doll 20 generally has a body 22 arranged in a circular shape resembling a doughnut or a bagel. The body 22 thus has a center opening 24 that can define a mouth opening of the doll 20 , as shown in each of the illustrated examples. The center opening 24 in the present example also defines a center axis of the body 22 . [0014] A pair of legs 26 extend radially outward from the body 22 and are positioned generally next to one another on the body. A pair of arms 28 extend radially outward from the body 22 , one each generally near a respective one of the legs. The region of the body 22 extending between the arms 28 and opposite the legs 26 defines a head region 30 of the doll. The region in which the legs 26 are attached is a bottom region 32 of the doll. The body 22 also has a front side 34 and a back side 36 . [0015] In one example, the front side 34 has a pair of stylized eyes 38 provided on a single piece of plastic 40 that is adhered in any suitable manner to the body 22 . The eyes 38 can alternatively be provided having a variety of different constructions and configurations without departing from the spirit and scope of the invention. In another example, a two dimensional representation of the eyes 38 can be drawn or sewn onto the front side 34 of the body 22 , if desired. [0016] The doll can also have a pair of hands 42 , one each disposed at the distal end of a respective one of the arms 28 . The hands 42 are connected to the arms at corresponding wrist regions 44 . The doll can further have a pair of feet 46 , one each disposed at a distal end of a respective one of the legs 26 . The feet 46 are connected to the legs 26 at corresponding ankle regions 48 . [0017] The doll 20 can also have a nose 50 attached to a front side 34 of the body 22 . In this example, the nose 50 is a ball which can be constructed in the same manner as the body 22 described below, or can be of many different alternative constructions. In another example, a two-dimensional representative nose can simply be drawn or sewn to the body 22 . The doll 20 also has a plurality of strands of hair 52 extending from the head region 30 of the body 22 . The hair 52 is described in greater detail below. [0018] As shown in FIGS. 5 - 7 , the body 22 has an exterior layer of soft, pliable material 60 . In one example, the exterior layer 60 is a fabric. A resilient filler material or stuffing 62 is encased within the exterior layer 60 . In one example, the stuffing can be packed loose fibers or strands of material, such as cotton wadding or padding. The exterior layer 60 and stuffing 62 , in combination, provide a soft or plush feel for the doll 20 . However, the stuffing 62 within the exterior layer 60 of the body 22 , legs 26 , and arms 28 is packed densely enough to generally retain the three dimensional shapes of the doll 20 . [0019] [0019]FIGS. 5 and 6 illustrate a skeleton structure 70 embedded in the stuffing 62 within parts of the body 22 , arms 28 , and legs 26 . The skeleton structure can take on various forms and configurations from that disclosed herein and yet fall within the scope of the invention. In the disclosed example, the skeleton structure 70 has a primary segment 72 and a pair of arm segments 74 . The primary segment 72 is bent to follow the contour of the body 22 from a leg position in the bottom region 32 , around the body 22 through the head region 30 , and to the other leg position at the bottom region. The distal ends of the primary segment 72 each terminate near a respective one of the feet 46 . A U-shaped loop 76 is provided in the distal ends of the primary segment 72 adjacent each foot to prevent contact of the sharp end of the wire with the bottom of the foot. Each arm segment 74 has a proximal end coupled to the primary segment 72 via a U-shaped loop 78 at a corresponding arm position within the body 22 . The distal ends of the arm segments 74 terminate near each hand 42 . [0020] The skeleton structure 70 is comprised of a bendable wire 80 that has a flexible plastic coating 82 . The wire 80 can be bent and can retain the selected position. As shown in FIGS. 2 - 5 , the arms and legs can be repositioned and the selected positions will be retained by the skeleton structure 70 . Though not shown, the body 22 can also be reconfigured to change the mouth opening or body shape and the primary segment 72 will retain the selected body orientation. The plastic coating 82 protects the wire from corrosion and assists in preventing injury to those using the doll. The plastic coating 82 also assists in increasing surface friction of the skeleton structure 70 so that the skeleton does not easily slide and reposition within the body 22 . [0021] In one example, the loops 76 or the distal ends of the primary segment terminate slightly into each foot 46 beyond the ankle regions 48 . In this way, the feet can be repositioned relative to the legs at the ankle region 48 , if desired. Similarly, the distal ends of the arm segments 74 each terminate slightly into the hands 42 beyond the wrist regions 44 . In this way, the hands can be repositioned relative to the arms at the wrist regions 44 . [0022] As shown in each of the various FIGS. 1 - 9 , the hair 50 is posable. It can be repositioned or manipulated into any one of many different styles. The hair is fabricated so that it can retain the selected style. Thus, the look of the doll 20 can be varied as desired by a doll user. To render the hair 50 posable, the strands are fabricated from a material that is flexible and yet substantially holds a selected position. The strands can be captured and sewn between front and back layers of the exterior fabric layer 60 . The strands can alternatively be spread over an area of the head region 30 and attached by means of looping an elongate strand through the fabric to form two hair strands. [0023] Also as shown in the various FIGS. 1 - 9 , the style and look of the doll can vary considerably and yet fall within the scope of the present invention. The fabric materials of the body 22 , arms 28 , and legs 26 can be selected, combined, and sewn so as to make the doll appear to be wearing clothing. For example, the doll in FIG. 1 appears to have sleeves and the doll in FIGS. 4 and 5 is wearing a hat. The dolls can also be provided in a variety of colors. Additionally, as shown in FIGS. 1 and 4, the front side 34 of the body 22 can include various markings or features so as to give the appearance of a beard 84 , a mustache 86 , freckles 88 , and the like. The hands can be fabricated in a variety of hand positions or gestures. The feet can be fabricated to appear to be wearing shoes as shown in FIG. 1. As shown in FIG. 6, the feet can also be fabricated to include a relatively rigid pad 90 of plastic or the like to define a foot bottom. Such a foot bottom can assist the doll in standing on a surface, if desired. [0024] Although certain dolls have been disclosed and described herein in accordance with the teachings of the present invention, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all embodiments of the teachings of the invention fairly falling within the scope of the appended claims, either literally or under the doctrine of equivalents.

A posable doll has a generally tubular body arranged in a circular shape with a center opening. A pair of legs extend radially outward from the tubular body and each of the legs has a length. A pair of arms extend radially outward from the tubular body and each of the arms has a length. A filler material is stuffed in the tubular body, the arms, and the legs. A wire skeleton extends around the circular shape within the tubular body and extends over a substantial portion of the length through each of the arms and the legs. The wire skeleton is capable of being bent to various positions and of retaining each of the various positions as desired.

TECHNICAL FIELD [0001] This invention relates to cable for use in strata control, especially to reinforce the roof and/or walls of underground mines and tunnels, to methods of manufacturing cable bolts and to manufacturing components and systems used in such methods. BACKGROUND [0002] Cable bolts are usually made from cable comprising a plurality of steel filaments wound together around a central wire to form a tendon. Resin and/or cement grout is used to fix the cable bolt to a borehole. To increase the effective bond strength between the cable bolt and resin or grout the bolts are often provided with spaced protuberances along the length of the cable. These protuberances are often known as bulbs or cages. The protuberances assist in preventing cable bolts from being pulled through the resin or grout, thus providing improved anchorage and load transfer between the cable, resin/grout and the surrounding strata. [0003] It is known that tensioning of the cable prior to cement grouting can cause the protuberance to collapse thus reducing the cable's effectiveness. In Australian patent 2004260817 there is a proposal to insert ball bearings into the cavities defined by the protuberances to reduce the likelihood of the protuberances collapsing when the cable is tensioned. This proposal has proved expensive to manufacture and unreliable due to the ball bearings being pushed out of the protuberances. There is also a need to displace the central wire to locate each ball bearing. In some cable bolts the central wire is replaced by a hollow tube which extends along the centre of the cable. Other disadvantages relate to the difficulty in automating the placement of the ball bearings and the ball bearing creates a stress concentration on the strands of the cable creating loads that lead to failure loads up to 25% less than the original strands ultimate tensile strength. [0004] In our earlier Australian patent application 2008200918 we disclose a cable bolt having a hollow strand which facilitates the passage of grout along the cable. It is important that the hollow strand does not get crushed by radial loads in non collapsible protrusions. [0005] It is these issues that have brought about the present invention. SUMMARY [0006] According to one aspect of the present invention there is provided a cable bolt comprising a plurality of flexible steel filaments formed around a central member, the cable bolt having spaced bulbous portions along the length of the bolt each bulbous portion defining a cavity containing a segmented ring that surrounds the central member to engage the filaments of the bulbous portion. [0007] In accordance with a further aspect of the present invention there is provided a method of manufacturing a cable having twisted flexible steel filaments over a central member, the method comprising forcing the filaments apart without plastically deforming the filaments, inserting a spacer through the parted filaments to sit between the filaments and the central member, and releasing the parted filaments to return against the spacer to form a bulbous portion. [0008] In one form, the filaments are forced apart by applying torsion to the filaments. In one form, the torsion is applied over a length of the cable to form bulbous portions spaced along the cable. [0009] In one form, in addition to or instead of, the filaments are forced apart by inserting a spreading tool between the filaments. [0010] In one form, the spacer extends around the central member. In a particular form, the spacer is a segmented ring that is placed in pieces through the parted filaments and formed into a ring surrounding the central member. In another form, the spacer may be a unitary element, such as helical wound member that is rotated onto the inner member through the parted filaments. [0011] In one form the torsion and/or spreading is applied over a section of the pre-wound cable to open the outer filaments over a set length to allow insertion of the ring segments around the central member before releasing the filaments forming a permanent non-collapsible single protrusion. The process may be repeated further along the pre-wound cable. [0012] In a further aspect of the present invention, there is provided an apparatus for forming bulbs in a cable having twisted flexible steel filaments over a central member, the apparatus comprising: [0013] a bulbing assembly releasably engagable with said cable, said assembly being operative to force the filaments apart without plastically deforming the filaments; and [0014] an inserting device operative to insert a spacer through the parted filaments to sit between the filaments and the central member. [0015] In use on releasing the parted filaments they return against the spacer to form a bulbous portion in the cable. [0016] In one form, the apparatus further comprises a frame; and a securing device for holding at least a portion of a cable with respect to frame. [0017] In one form the cable is fed through the bulbing assembly so that a plurality of bulbing portions are able to be formed along the cable. [0018] In another form, the bulbing assembly is movable relative to the apparatus frame to form spaced apart bulbing portions in the cable. Typically in this latter arrangement the cable remains stationary during forming of the plurality of bulbs but in another form, the cable may be moved so that both the cable and the bulbing apparatus move during bulb forming. [0019] In one form, the apparatus includes a feed assembly to feed the cable from a coil into the apparatus. In one form the cable, with bulbs formed therein, is progressed to a table and the apparatus further includes a cutting device to cut the cable to length as required in formation of cable bolts. BRIEF DESCRIPTION OF DRAWINGS [0020] An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which: [0021] FIG. 1 is a part sectioned side view of a typical cable bolt, [0022] FIG. 2 is a cross sectional view of the cable bolt, [0023] FIG. 3 is a schematic view of an apparatus for forming bulbs in a cable in accordance with an embodiment of this invention, [0024] FIG. 4 is a plan view of a bulbing apparatus of the apparatus of FIG. 3 , [0025] FIG. 5 is a detailed view of the bulbing apparatus of FIG. 4 , [0026] FIG. 6 is a perspective view of the bulb illustrating insertion of a segmented ring. For convenience components of the bulbing apparatus are not shown; and [0027] FIG. 7 is a perspective view illustrating the location of the segmented ring on a central strand of the cable bolt. DETAILED DESCRIPTION [0028] FIGS. 1 and 2 illustrate a cable bolt 10 . These drawings are taken from our earlier Australian patent application 2008200918, corresponding to U.S. Pat. No. 8,322,950, incorporated herein by reference. [0029] As illustrated in FIG. 1 , an embodiment of a resin anchorable cable bolt 10 comprises a flexible cable 11 formed from a plurality of wound co-extending strands in the form of wound co-extending steel filaments that extends along an axis C between opposite ends (being, relative to the direction the bolt 10 is installed in a bore in a substrate, such as a mine shaft roof, a distal end 13 and a proximal end 14 ). The cable 11 has a first portion 15 adapted primarily for resin point anchoring, and a second portion 16 adapted predominantly for cement grouting. [0030] As illustrated in FIG. 2 , the filaments comprise nine outer steel filaments 12 a spiral wound about a central hollow filament, or strand 12 b , located axially within the cable 11 . In one form, the hollow strand 12 b may comprise at least one region for resisting radial compression, in particular of a tensioning assembly which is discussed in more detail below. In alternative arrangements, the hollow strand 12 b may be plain, and/or more or fewer outer steel filaments 12 a may be used, in which case their relative diameter with respect to the hollow strand 12 b would be adjusted accordingly such that they are close fitting about the hollow strand 12 b . The outer steel filaments, or strands, 12 a are typically solid and of the type used for cable bolt or pre-stressed concrete applications. The hollow strand 12 b extends in the second portion 16 and not in the first portion 15 , however in alternative embodiments, the hollow strand may extend into the first portion 15 also. [0031] In the embodiment of FIG. 1 , the central hollow strand 12 b comprises profiling allowing flexibility of the cable 11 , while providing strength to resist crushing of the strand (i.e. radial compression of the cable). The hollow strand 12 b is flexible to allow coiling of the cable 11 such that the coil has a minimum diameter of 1 . 2 m without kinking the hollow strand 12 b . In alternative embodiments, the minimum coiling diameter without kinking the hollow strand may fall within the range of 0.8 m to 2.5 m, or 1 m to 2 m. In the embodiment illustrated in FIG. 1 , the profiling is in the form of a helical or spiral ribs 17 (see FIG. 7 ) along its entire length. The hollow strand 12 b is formed from a metal material, in this embodiment steel, but may be formed from a polymeric material, such as polypropylene, a polyethylene, or other appropriate polymer. [0032] Referring again to FIG. 1 , the cable bolt 10 further comprises a resin retainer 22 disposed between the first and second portions 15 , 16 of the cable 11 . The resin retainer 22 is affixed to the cable 11 and extends radially outwardly from the cable so as to substantially reduce the migration of resin from the first portion to the second portion within the bore during point anchoring of the bolt 10 . The resin retainer is typically formed from metal, however may be formed from any suitable polymer such as polypropylene or a polyethylene. [0033] The hollow strand 12 b is located in the second portion 16 of the cable bolt 10 and extends from the proximal end 14 of the cable 11 to a location 24 in the second portion 16 at or adjacent the retainer 22 . As illustrated in FIG. 1 , a nut 26 is located on or near the hollow strand 12 b at location 24 within the outer filaments 12 a , forming a bulb, or “nut cage” 28 . The nut cage is formed by spacing apart and forcing outwardly all of the steel filaments 12 along a discrete section of the cable 11 and placing the nut 26 about the hollow strand end 24 . [0034] The first portion 15 includes an end collar 31 for holding together the strands 12 a at the distal end 13 , and a plurality (three in the illustrated case) of radially outwardly extending resin mixing protrusions in the form of “bird cages” 32 , where a ball bearing (or other rigid object) is inserted in a partially unwound portion of strands 12 a. [0035] It is desirable in some instances to form bulbs along the second portion 16 (in addition to the first portion 15 ) and/or to extend the hollow strand 12 b into the first portion 16 . As such it is desirable to be able to form bulbs about the hollow strand 12 b . Further to facilitate manufacturing processes, it is desirable that the bulbs are formed without unwinding of the steel filaments. [0036] FIGS. 3 to 6 illustrate an apparatus for forming non collapsible spaced protrusions (or bulbs) 18 about the hollow strand 12 b of the flexible cable 11 . These bulbs 18 incorporate a segmented ring 40 ( FIG. 7 ) that prevents collapse of the bulb 18 whilst ensuring against radial compression of the hollow strand 12 b. [0037] The method of forming the bulbs 18 and locating the segmenting ring 20 is discussed with particular reference to the bulbing apparatus 100 shown FIGS. 3 to 5 . [0038] As best shown in FIG. 3 , the apparatus 100 includes a bulbing assembly 102 mounted on a frame 104 . A cable 11 is arranged to be fed from a coil (not shown) mounted within a coil handler 106 . Once bulbs are formed in the cable 11 (as discussed in more detail below) by the bulbing assembly 102 , the cable is progressed to a payout table 108 . A cutting device 110 is disposed between the frame 104 and the payout table 108 and is arranged to cut the cable once a desired length (typically of 8 m but it may be more or less depending on requirements) is passed onto to the table. The cut lengths of cable can then be further processed to form the final cable bolts as required. The bulbing process is preferably fully automated and controlled by a control system 112 which may include, as illustrated, a control cabinet 114 and operator interface 116 . [0039] As best shown in FIGS. 4 and 5 , bulbing assembly 102 includes three components; namely torsioning device 118 , spreader 120 , and inserter 122 . In general, the torsioning device 118 is designed to twist the cable bolt 10 to force the filaments 12 a apart to define a gap. The spreader 120 (shown in the form as a pair of plates or knives 56 , 57 ) is designed to further spread adjacent filaments that allows the inserter 122 adequate space to enable the segmented ring 40 to pass through the parted filaments 12 a to be located in an interfitting arrangement on the central strand 12 b. [0040] In the illustrated embodiment, the torsioning device 118 discloses the use of mandrels 51 , 52 positioned around the cable 11 at spaced intervals to define a length of cableas shown in FIGS. 4 and 5 . Each mandrel 51 or 52 includes a three jaw chuck 53 , 54 which can be brought into clamped engagement with the periphery of the cable 11 . The chucks 53 , 54 are clamped to the cable and are either rotated in opposite directions or one is rotated relative to the other to place the filaments 12 a of the cable into torsion which has the effect of parting the filaments 12 a and forming a protrusion 18 at the mid span of cable between the chucks 53 , 54 . With the chucks 53 , 54 held in position to maintain the torsion, spreader knives 56 , 57 are pushed between selected parted filaments 12 a and rotated to further move the filaments apart. This provides access to the inserter 122 (in the form of robotic arms 59 , 60 ) which place segments 41 , 42 of the ring 40 on opposite sides of the hollow strand 12 b and then fitted together as shown in FIGS. 6 and 7 . [0041] As shown in FIG. 7 , each ring segment 41 , 42 has a projection 43 that is a snug fit within a similarly profiled recess 44 on the other segment 42 of the ring to allow the segments 41 , 42 to form a circular one piece ring 40 as shown in the left hand side of FIG. 6 . Once the ring 40 has been placed on the central strand 12 b the knives 56 , 57 can be removed and, the torsion applied by the mandrels 51 , 52 can be released causing the parted filaments 12 a to close onto the periphery of the ring 40 thereby locating the ring 40 in the cavity of each protrusion 18 on the central strand 12 b . By a steady release of the torsional load the parted gap between the filaments closes and the filaments 12 a contact the ring 40 to form an expanded non-collapsible bulb 18 . [0042] The location of the ring 40 on the hollow central strand 12 b ensures that when the cable bolt is tensioned the protrusion 18 does not collapse. The segmented ring 40 , by forming a single annular ring ensures that there is no danger of the segments 41 , 42 crushing the central strand 12 b . The dovetailed inter fitting of the segments 41 , 42 ensure that radial forces on the ring 40 are evenly distributed around the periphery of the strand 12 b . The segmented ring 40 whilst preventing radial collapse of the strand 12 b can also allow a degree of movement between the strand 12 b and ring 40 thus maintaining the flexibility of the final cable. [0043] In the form illustrated, the torsional and spreading forces that are placed on the cable bolt as it is twisted through use of the mandrels 51 , 52 and spreader 120 is insufficient to cause plastic deformation of the wire filaments 12 a. [0044] Once the bulb 18 is formed, the cable 11 can then be fed through the bulbing assembly 102 (in a direction towards the payout table 108 ) such a subsequent portion of the cable 11 aligns with the bulbing assembly. The bulbing assembly is then able to form a further bulb 18 in the cable allowing separate spaced bulbs 18 to be formed in the cable 11 . [0045] In an alternative form, the bulbing assembly may be designed to move along the length of the cable 11 to form spaced apart bulbs in the cable 11 . In either process, in this manner the cable 11 can have non collapsible grouting protrusions (in the form of bulbs 18 ) at desired intervals along the length of the cable 11 . [0046] This process can be completed off a reel and wound back into smaller reels; or to cut to lengths. Alternatively, the process can use precut lengths. [0047] It is also envisaged that the mandrels 51 , 52 and chucks 53 , 54 may be split to facilitate attachment to the cable 10 without the need to pass the cable through the mandrels and chucks. [0048] It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country. [0049] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

A cable bolt comprising a plurality of flexible steel filaments formed around a central member, the cable bolt having spaced bulbous portions along the length of the bolt each bulbous portion defining a cavity containing a segmented ring that surrounds the central member to engage the filaments of the bulbous portion.

FIELD OF THE INVENTION The invention generally relates to a system and method for dynamically reconfiguring proxy server networks so that they may share extra capacity. BACKGROUND Network systems, such as the internet and, more specifically, the World Wide Web (“WWW”), utilize servers to process requests for information. However, with increased popularity, these network systems are gradually becoming more overloaded since the number of requests for information has been sharply increasing. When a server becomes overloaded, it may be unable to receive new requests, may be slow to process the requests it has already received, and may yield server errors. On the WWW, such overloading can be extremely detrimental. As web browsers have become the primary interface for access to many network and server services, more businesses have begun using the WWW to market their products or for advertising purposes. To these businesses, prompt and efficient access to their sites is extremely desirable, as it is well known that WWW users tend to avoid sites which load slowly or yield server errors. However, when a popular web page is hosted by a single computer or server, the internet traffic to the computer can be overwhelming. To address this situation, a number of server-based solutions have been proposed and/or implemented to attempt to ensure that Internet services remain available, scalable and well-balanced. One of the most popular solutions has been the use of load balancing, which involves distributing requests among servers (e.g., different servers on a WWW site) in order to ensure that any one server does not become unduly burdened. One conventional load balancing technique involves the use of a domain name server (hereinafter “DNS”). This device is responsible for resolving uniform resource locators or “URLs” (e.g., “www. .com”) to specific IP addresses (e.g., 111.222.111.222). In this regard, a Web site having several servers may operate under a single URL, although each server is assigned a different IP address. It is up to the DNS to determine which server to route a web user to when a request is made. For example, a round-robin DNS performs load balancing by routing requests to these servers in sequential rotation based on their IP addresses. When a web site has several servers operating under the same URL, those extra servers are often called “proxy” or “mirror” servers. The proxy server stores exactly the same web site information found in the originating server. Thus, when a user makes a request to visit a website that uses a proxy server, the user will see the same exact website whether or not the user is visiting the proxy server or the original server. As the need for proxy services has increased, some companies have begun to operate their own proxy networks for the purpose of delivering content for certain subscriber WWW sites. However, the agreements these proxy network providers have with the subscriber WWW sites is generally long-term in nature. Thus, the proxy networks are generally configured for the maximum expected traffic at the subscribed WWW sites and there is often unused capacity on the proxy network being wasted. What is needed is a method to let the proxy network dynamically sell the extra capacity so that it is not wasted. SUMMARY The system and method is directed to dynamic proxy reconfiguration implemented in interconnected network servers. In particular, the invention is directed to a computer-executable program for use in proxy network servers which enables each proxy server to dynamically sell its unused capacity to other web sites for specific periods of time. The invention has particular utility in connection with World Wide Web servers and proxy servers, but can be used with other servers where proxy servers may be present, such as CORBA servers, ORB servers, FTP servers, SMTP servers, and Java servers. The system and method may be used to dynamically sell extra capacity to other websites to make additional profit. In a preferred embodiment, a proxy server network monitors its servers to determine whether any unused capacity exists. If any unused capacity exists, the proxy server can sell an estimated or set amount of unused capacity for a set amount of time through various market mechanisms to web site server operators. Once a purchaser has been identified, a controller program either on the domain name server of the proxy network or on a separate server connected to the proxy server network ensures that the proxy network's domain name server receives information on the purchaser website. This information includes the name to address map of the purchaser web site network and the content of those websites which will be stored for the purchased period of time on the proxy servers. After this information is stored on the domain name server of the proxy server network, the domain name server of the proxy server network can begin mapping a fraction of the overall mapping requests to the proxy servers. The overall fraction of requests mapped by the domain name server will depend on the initial agreement between the proxy network and the purchaser. For example, if the unused proxy capacity was determined based on an estimate of extra capacity available, the proxy network might service the purchaser website's mapping requests using its best efforts for the time it agreed to provide proxy server capacity to the purchaser. In such a case, the final bill due the proxy server network will be based on the purchaser website's actual usage of the proxy server capacity. The remaining fraction of mapping requests which the proxy server network does not handle are routed back to the purchaser website's servers for mapping. However, if the purchaser supplied the controller program with an assignment algorithm, the domain name server of the proxy server network will route the remaining mapping requests to servers in the purchaser website's network. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a hardware diagram illustrating the data flow of the preferred embodiment for the system and method to let a proxy network dynamically sell unused capacity. FIG. 2 is a hardware diagram illustrating the data flow of an alternative embodiment for the system and method to let a proxy network dynamically sell unused capacity. FIG. 3 is a block diagram illustrating a typical path taken by a user's request for a particular address on the internet, and the path taken in receiving that address. FIGS. 4-8 are flowcharts illustrating embodiments of the system and method to let a proxy network dynamically sell unused capacity. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The system and method is directed to reconfiguring proxy network servers so that proxy networks can dynamically sell unused capacity to other networks for specific periods of time. This unused capacity can be used for delivering content normally found on the purchaser's network, so that the overall load on the purchaser network is reduced. Although the system and method will be described in the context of the WWW, and more specifically the content of WWW servers, it is not limited to use in this context. Rather, the system and method can be used in a variety of different types of networking systems with a variety of different servers. For example, the system and method can be used in intranets and local area networks, and with CORBA servers, ORB servers, FTP servers, SMTP servers, and Java servers, to name a few. FIG. 1 is a basic hardware diagram of a networking system capable of carrying out the processing in accordance to one embodiment of the system and method. More specifically, FIG. 1 depicts the topology of a website network and proxy network and how they connect to the internet and to each other. FIG. 1 shows a proxy network's connections to the internet consisting of a proxy network server cluster 5 , a packet filter 4 , a local domain name server of the proxy server network which contains a controller program 3 , and a router for the proxy network 2 to connect to the internet 1 . A similar set of hardware components exists for a purchaser web site server cluster 9 to connect to the internet 1 . A brief description of this hardware is provided below. Router 2 receives requests for information stored on the proxy network server cluster 5 from a remote location via the internet 1 . Router 2 routes these requests, which typically comprise URL's, to the local domain name server of the proxy server network 3 . The local domain name server of the proxy network 3 receives a URL from router 2 and resolves the domain name in the URL to a specific IP address in proxy server cluster 5 . Router 6 and local domain name server 7 perform the same tasks as Router 2 and domain name server 3 , except that they are routing requests to a purchaser web site server cluster 9 . Packet filters 4 and 8 are generally found in most networks and serve as firewalls for the internal networks consisting of proxy network server cluster 5 and purchaser web site server cluster 9 respectively. All transactions into and out of an internal network are handled by the network's packet filter. Packet filters determine which services of the internal network may be accessed from the internet 1 , which clients are permitted access to those services, and which outside services may be accessed by anyone on the internal network. Thus, packet filters 4 and 8 analyze data packets passing through them and filter those packets according to the settings on each network, restricting access where necessary and allowing access where appropriate. The proxy network server cluster 5 and the purchaser web site server cluster 9 are both internal networks which are typically comprised of multiple servers. Sometimes these servers are all connected through a mainframe (or similar computer). The servers that make up each server cluster 5 and 9 are used to store files, such as website files, so that users may later access and view the files. FIG. 2 illustrates an alternate embodiment to the hardware structure depicted in FIG. 1 . In FIG. 2 , instead of storing the controller program on the local domain name server of the proxy network 3 , the controller program is located on its own server 10 which is connected to the local domain name server 11 . FIG. 3 is a hardware diagram depicting the general path taken by a user's request for a particular address on the internet, and the path taken in receiving that address used in the prior art. A user 50 using a web browser requests a web site address using a URL. The URL is then sent to a local domain name server 51 on the user's 50 own local network. Domain name servers are responsible for resolving uniform resource locators or “URLs” (e.g., “www. .com”) to specific internet or internet provider (“IP”) addresses (e.g., 111.222.111.222). If the user 50 is requesting an address on the local network, the local domain name server 51 will have the corresponding internet address and will relay the internet address back to the user 50 . The web browser of the user 50 will then take the user 50 directly to the requested site. Otherwise, if the user 50 is not requesting a URL which corresponds to an IP address on the local network, the local domain name server 51 will not have corresponding IP address and the local domain name server 51 will have to contact a root domain name server 52 to get the information. If the root domain name server 52 does not have the IP address corresponding to the URL submitted by the user 50 , then various minor domain name servers 53 and 54 will have to be contacted. If the minor domain name servers 53 and 54 don't have the internet address, the local domain name server 55 of the network 56 the user is contacting will be contacted to provide the IP address. However, often the minor domain name servers 53 and 54 will have the IP address to the URL requested by the user, and the local domain name server 55 of the network that the user is contacting will not have to be contacted. FIG. 4 illustrates the initial process steps of the present invention for dynamically reconfiguring a proxy network to sell extra capacity to other networks, specifically WWW server networks. To begin, in steps 100 and 101 a determination must be made as to whether any unused proxy server capacity actually exists for a period of time which could be marketed to a web site operator. This determination can be made by a proxy network operator or by the controller program monitoring the proxy server network. The controller program is stored either on its own server 10 connected to the proxy server network, or on the local domain name server of the proxy server network 3 . Once it is determined that some unused proxy server capacity is available, step 102 follows where the unused proxy server capacity is marketed through various mechanisms known to persons skilled in the art. Some of the various ways in which the unused proxy server capacity can be marketed includes, but is not limited to, online auctions on the internet or on real-time continuous markets which are accessible via the internet. The unused proxy server capacity can also be sold either as an estimate (i.e., the proxy server network will use its best efforts to provide the capacity being sold and will possibly even supply additional capacity if it becomes available at a predetermined rate) or for a specific amount. In either case, the unused proxy server capacity will be sold to a purchaser for a limited, set time (i.e., the proxy server network will accept purchaser website's requests for four hours or for four hours on a daily basis). Payment for the purchase of proxy server capacity can be made through various mechanisms known to persons skilled in the art. For example, a credit card could be used or money could be wired from a specific account. If some unused proxy server capacity is sold, step 103 then follows where the controller on the proxy server network is notified about the sale. Purchaser information is then sent to the controller in step 200 in FIG. 5 . Such information includes, but is not restricted to, the purchaser's billing information such as credit card information, billing address, etc. In step 201 , the controller program ensures that the local domain name server of the proxy network is the primary domain name server, which is the only domain name server that can assign names to the proxy servers. As illustrated in FIG. 3 , a user 50 who requests a website using a URL must have the URL mapped to a numerical IP address before accessing the actual website. However, often the user 50 does not have to contact the local domain name server of the network to get the IP address which corresponds to the URL the user 50 is requesting. In such cases, other minor domain name servers 53 and 54 , which are outside the network, are able to provide the user 50 with the requested IP address. Step 201 ensures that local domain name server of the proxy network 55 will serve all naming requests. Therefore, the root domain name server 52 and minor domain name servers 53 and 54 will not be able to provide the user 50 with any name to address translations for the proxy server network. In this fashion, only the local domain name server 55 will have to be updated when proxy server network dynamically provides unused capacity. In step 202 , the primary domain name server receives the name to address map of the purchaser web site and routes copies of the purchaser's website content to servers on the proxy network. Therefore, the primary domain name server 3 handles all name to address translation requests for the purchaser website for the time that the purchaser has paid to use the proxy server capacity. The name to address map of the purchaser website can be obtained by the primary domain name server from the purchaser website's local domain name server. In addition it could be sent to the primary domain name server by a purchaser website operator along with an assignment algorithm or other mapping information the purchaser would like the proxy server network to know. The controller program would ensure that the information is received and handled appropriately. In step 203 , the controller program determines how to handle the mapping requests to the purchaser's website by examining whether or not the unused proxy capacity was purchased based on an estimate of usage. For example, if the original sale of the proxy server capacity was based on an estimate of unused capacity available, or if purchaser just wanted to purchase whatever unused proxy capacity existed, the controller program will have to initiate a steps 204 and 205 to route the mapping requests for the purchaser. In step 204 , the primary domain name server routes a fraction of the overall mapping requests for the purchaser website to servers in the proxy network based on the amount of unused proxy capacity available. In step 205 , the primary domain name server monitors the load levels on the proxy servers to adjust the fraction of mapping requests for the purchaser website routed to proxy servers based on the amount of unused capacity available at any given time. This ensures that the proxy server network is never overburdened by the number of requests to the purchaser website. Thus, the dynamic sale of proxy capacity to other networks never interferes with the other operations of the proxy server network. In step 206 , the primary domain name server determines whether there are any mapping requests that cannot be routed to the proxy server due to a lack of proxy server capacity. If there are some, the primary domain name server next checks to see if the purchaser of the proxy capacity provided an assignment algorithm for handling these requests in step 300 in FIG. 6 . If an assignment algorithm was provided, the primary domain name server routes all the mapping requests that the proxy network cannot handle to servers in the purchaser website's network in step 301 . Otherwise, if an assignment algorithm was not provided, step 302 ensures that those mapping requests are returned to the domain name server of the purchaser website's network. At this point, the controller program determines in step 500 in FIG. 8 whether the purchaser's period of time for using capacity on the proxy server network has expired. If it hasn't, the primary domain name server continues to map requests for the purchaser website. Otherwise, in step 501 , a billing cycle is initiated. At this point, the controller program will determine whether or not to bill the purchaser a set amount or for the actual usage of the proxy network. If set amount of unused proxy capacity was originally purchased in step 102 , the purchaser is billed the agreed upon amount as demonstrated in step 504 . Otherwise, the purchaser is billed in step 503 for the overall actual usage of the proxy server capacity as determined by the controller program which monitored the purchaser's use of proxy capacity. At this point the controller program ends with regards to a particular purchaser, and begins step 100 to determine whether any unused proxy capacity is available. Going back to step 203 , if the purchaser did not buy proxy capacity based on an estimate, the primary domain name server will map a fraction of the received mapping requests to servers in the proxy network based on the actual proxy capacity purchased. Therefore, at no time will the amount of proxy capacity servicing mapping requests for the purchaser website's network be greater than the amount originally purchased. Additional mapping requests received by the primary domain name server which are not mapped by the primary domain name server because it would require more proxy capacity than was purchased, will be handled in steps 402 , 403 , and 404 in the same fashion as steps 300 , 302 , and 303 discussed above. Finally, an alternative embodiment exists as shown by FIG. 2 where the controller program is stored on its own controller server 10 . This server is then responsible for handling all of the mapping requests much like the local domain name server 3 . The above description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements. Various modifications to the preferred embodiments will be readily apparent to those skilled in the art and the generic principles herein may be applied to other embodiments. Thus, the present invention is not intended to be limited to the embodiment shown but is to be accorded the widest scope consistent with the principles and features described herein.

A method directed to a dynamic proxy reconfiguration which is implemented in plural network servers. The invention is directed to a computer-executable program for use in proxy network servers which enables each proxy server to dynamically sell its unused capacity to other web sites for specific periods of time. The invention has particular utility in connection with World Wide Web servers, but can be used with other servers where proxy servers may be present.

BACKGROUND OF THE INVENTION [0001] 1. Field the Invention [0002] The present invention relates to a misfire deciding method and system for an internal combustion engine. [0003] 2. Description of the Related Art [0004] As a misfire deciding method in an internal combustion engine, a method has been proposed for directly measuring the pressure in a combustion chamber, for example, by forming a pressure conduit leading to the combustion chamber in a cylinder head and by arranging a partition type pressure sensor in the pressure conduit. The formation of this pressure conduit in the cylinder head, however, involves complex machining which inevitably raises the manufacturing cost. A more convenient method for measuring the internal pressure uses a pressure sensor (hereinafter called a “gasket type pressure sensor”) which is mounted on the mounting seat of a spark plug, as disclosed, for example, in Japanese Patent Laid-Open No. 290853/1994. [0005] [0005]FIG. 3 exemplifies an internal pressure profile as measured by an internal pressure sensor for one cycle in the combustion engine. The solid curve indicates the profile for normal combustion timing, and the single-dotted curve indicates the profile for a misfire timing. When an intake valve is closed, the inside of the combustion chamber is sealed, and the mixture is compressed as a piston rises, so that the internal pressure rises. Moreover, the spark plug sparks at a crank angle (or an ignition timing) before top dead center (TDC). When the mixture is normally ignited with that spark, the internal pressure is further raised by the explosion of the mixture. By this pressure rise, the rise in the internal pressure is continued for a while, even after the piston passes through the TDC and turns downward, and the internal pressure is reduced after the piston goes down to some extent. Therefore, the internal pressure measured profile assumes an asymmetric shape in which the peak position is shifted to a larger angle side than the crank angle (i.e., an αTDC) corresponding to the TDC. When the ignition ends unsuccessfully with a misfire, on the other hand, no pressure rise due to the explosion occurs so that the pressure assumes a maximum value at the TDC where the volume in the combustion chamber is at a minimum. After this, the piston moves down with the pressure change merely following a profile which is inverted relative to that of the rising time. Therefore, the internal pressure measured profile thus obtained is generally symmetric so as to have a peak position at the αTDC. Thus, between the normal combustion time and the misfire time, differences apparently occur both in the peak value of the internal pressure measured profile and in the symmetry of the profile. [0006] However, the misfire decision using only one point of the internal pressure peak value level has numerous error factors and lacks accuracy because it does not take into consideration the tendency of the entire profile. Japanese Patent Laid-Open Nos. 321752/1992, 72448/1992 and 325755/1992, therefore, discloses a method for deciding a misfire by comparing the magnitudes of a before top dead center pressure integrated value SI obtained by integrating the internal pressure measured values for a constant integration period defined in the before top dead center period and an after top dead center pressure integrated value S 2 obtained by integrating the average pressure information for a constant integration period defined in the after top dead center period. In short, by using the integrated values, the tendency of the entire internal pressure measured profile can be reflected in an average form on the decision result so that a more accurate misfire decision can be made. [0007] Here, the method using the gasket type pressure sensor indirectly measures the internal pressure, in that the fastening force of the spark plug fixing the sensor is loosened by the internal pressure. As compared with the method of measuring the internal pressure directly through the pressure conduit by using the partition type sensor, therefore, there are a number of factors causing the absolute value of the measured pressure value to fluctuate. More specifically, variations in the force for fastening the spark plug and in the performance of individual piezoelectric elements easily cause the measured value level of the internal pressure to fluctuate, such that the measured value and its integrated value vary for a given internal pressure, easily resulting in an erroneous decision. In the above-specified patent publications, however, there is no disclosure of any specific means for reducing the adverse influences of these variation-causing factors. SUMMARY OF THE INVENTION [0008] It is therefore an object of the present invention to provide a misfire decision method and system for an internal combustion engine, which can be executed conveniently and inexpensively by using a gasket type pressure sensor and which can at all times make an accurate misfire decision while being hardly influenced by variations in the mounting arrangement or performance of the piezoelectric elements. [0009] In order to achieve the above-specified object, the invention provides a misfire deciding method for an internal combustion engine, characterized by: [0010] acquiring an internal pressure measured value based on the internal pressure of an internal combustion engine, to which a spark plug is attached, from the output of a pressure sensor mounted in a mounting seat of the spark plug; [0011] calculating the integrated value of the internal pressure measured values for a first constant integration period in a period (as will be called the “before top dead center period”) after an intake valve is closed and before a crank angle reaches top dead center, and setting the calculated value to a before top dead center integrated value S 1 ; [0012] calculating the integrated value of the internal pressure measured values for a second constant integration period in a period (as will be called the “after top dead center period”) after the crank angle reaches top dead center and before an exhaust valve is opened, and setting the calculated value to an after top dead center integrated value S 2 ; [0013] calculating a differential integrated value S 1 −S 2 between the after top dead center integrated value S 2 and the before top dead center integrated value S 1 ; and [0014] calculating a first correction reference value using the internal pressure measured value at a correction measurement point set for the before top dead center period, to correct the differential integrated value with the first correction reference value, to thereby make a misfire decision on the basis of the corrected differential integrated value. [0015] The invention provides a misfire deciding system for an internal combustion engine, comprising: [0016] a pressure sensor mounted in a mounting seat of a spark plug for acquiring an internal pressure measured value based on the internal pressure of an internal combustion engine having the spark plug mounted therein; and [0017] a decision unit for: calculating the integrated value of the internal pressure measured values for a first constant integration period in a period (as will be called the “before top dead center period”) after an intake valve is closed and before a crank angle reaches the top dead center, and setting the calculated value to a before top dead center integrated value Si; calculating the integrated value of the internal pressure measured values for a second constant integration period in a period (as will be called the “after top dead center period”) after the crank angle reaches top dead center and before an exhaust valve is opened, and setting the calculated value to an after top dead center integrated value S 2 ; calculating a differential integrated value S 1 −S 2 between the after top dead center integrated value S 2 and the before top dead center integrated value S 1 ; and calculating a first correction reference value using the internal pressure measured value at a correction measurement point set for the before top dead center period, to correct the differential integrated value with the first correction reference value, to thereby make a misfire decision on the basis of the corrected differential integrated value. [0018] In the misfire deciding method and system of the invention, as shown in FIG. 4, the internal pressure measured profile for a constant period before and after the top dead center is determined so that the misfire decision may be made on the basis of the difference between the before top dead center pressure integrated value S 1 and the after top dead center pressure integrated value S 2 , as obtained for the before top dead center period and for the after top dead center period, respectively, that is, the differential integrated value ΔS≡(S 2 −S 1 ). The method of making the misfire decision on the basis of the differential integrated value ΔS is convenient and is advantageous for easily canceling the influence of thermally caused drifts of the internal pressure measured values as described below. In either event, however, the misfire decision using the gasket type pressure sensor is easily caused to exert influences on the internal pressure measured value level due to variation in the fastening force of the sensor by the spark plug or in the performance of the piezoelectric element. [0019] In the invention, therefore, the correction measurement point is set for the before top dead center period, and the first correction reference value is calculated using the internal pressure measured value at the correction measurement point, to correct the differential integrated value ΔS with the first correction reference value, to thereby make the misfire decision on the basis of the corrected differential integrated value ΔS. The correction measurement point set within the before top dead center period is relatively hardly influenced by the pressure rise due to the ignition/explosion of the fuel so that the internal pressure measured value obtained at the measurement point can be used as the reference value. By standardizing the individual measured values forming the internal pressure measured profile in comparison with that reference value, therefore, fluctuations in the internal pressure measured value levels due to the aforementioned factors can be suppressed to make a misfire decision of a higher accuracy. [0020] At an idling time or at the time of running on level ground at constant speed, for example, the air-fuel ratio or the fuel consumption rate are substantially constant. If the crank angle at the correction measurement point is known, therefore, the internal pressure can be estimated from the volume of the combustion chamber at the correction measurement point. If the internal pressure measured value with the gasket type pressure sensor is corrected to match the estimated value of the internal pressure, therefore, the internal pressure measured value can be standardized even with variation in the sensor fastening force and in the piezoelectric element performance. [0021] In the vigorously changing situation of the running state of the internal combustion engine, on the other hand, the absolute value of the internal pressure is difficult to estimate even if the correction measurement point is set at the common crank angle position. According to the following method, however, the correction to standardize the internal pressure measured value can be rationally made without such an absolute value estimation. As shown in FIG. 4, more specifically, two different correction measurement points are set within the before top dead center period, and a first correction reference value is calculated as a difference of ΔP 0 ≡P 2 −P 1 between the internal pressure measured values P 1 and P 2 obtained for those two correction measurement points. If these two correction measurement points are individually set at constant crank angle positions, the volumetric change in the gas between the two correction measurement points always takes a determined value, and the difference ΔP 0 has a meaning as the reference pressure change corresponding to the constant volumetric change. The measured value of the difference ΔP 0 fluctuates with the aforementioned dispersions in the fastening forces or the piezoelectric element performances, and the internal pressure measured value to be used for the misfire decision also fluctuates with the same tendency. If the internal pressure measured value is displayed by correcting it with a relative value calculated by dividing it by the difference ΔP 0 for the reference pressure change, therefore, the influences of the aforementioned dispersions can be effectively reduced not through the absolute value correction of the internal pressure. [0022] Next in the invention for making the misfire decision with the differential integrated value ΔS, the value of (S 1 −S 2 )/ΔP 0 calculated by the division with the difference ΔP 0 of the internal pressure measured value or the first correction reference value is calculated (Formula (1) of FIG. 4) as a decision index λ, and the misfire decision is made on the basis of the decision index λ. Then, the misfire decision using the value ΔS can be made more accurately and reproducibly. Even if the peak value of the internal pressure measured profile fluctuates by the aforementioned factors so that the measured value ΔS itself takes a different value such as ΔS A (=S 2A −S 1A ) and Δ SB (=S 2B −S 1B ), as shown in FIGS. 5 ( a ) and 5 ( b ), the influences of the fluctuations can be drastically reduced by dividing those values by the aforementioned differences ΔP OA and ΔP OB . [0023] For these integrations, it is necessary to measure the internal pressure P as a function of time or crank angle. In FIG. 4, the internal pressure is measured as a function P(α) of the crank angle α. When the integration period of the before top dead center period is expressed by [α 1 , αTDC] whereas the integration period of the after top dead center period is expressed by [αTDC, α 2 ], for example, the values S 1 and S 2 can be calculated on the basis of Formulas (2) and (3) of FIG. 4. In the computer processing, the values S 1 and S 2 are calculated by numerical integrations by sampling the internal pressure measured value P at every minute angles δα while monitoring the crank angle α by a crank angle sensor or the like. In case the correspondence between the crank angle α and the time can be grasped, the integration variable should not be limited to the crank angle α but can be exemplified by the time t in a more convenient method. In order to lighten the influences of the engine speed (for a period of one cycle), it is then effective to average and use the time-integrated value of the internal pressure measured value P by the measured value of the prevailing engine speed. [0024] Hereinafter, the integrated value of the internal pressure measured value P conceptionally includes not only the mathematically integral value (Formulas (2) and (3) of FIG. 4, as will be called the “mathematically integrated value”) by the integral variable when the value P is expressed as a function of the crank angle α (or another parameter (e.g., the time t) which can correspond one to one to the value α) as the integral variable but also another operation value, if this value reflects the integrated value. If the sampling interval of the internal pressure measured value is constant, for example, the added value of the sampled internal pressure measured values for a constant period is the operation value reflecting the mathematically integrated value so that it can be adopted as the integrated value, as defined herein. Moreover, the value calculated by dividing the mathematically integrated value or the added value by the width of the integration period or the number of added data expresses the average value of the internal pressure measured values for the individual periods and can be adopted as the integrated value, as defined herein. [0025] If it is considered that the measurements of the internal pressure are ideally done, the differential integrated value ΔS is zero at the misfire. It is, therefore, theoretically possible to decide the combustion to be a misfire, if the value ΔS is zero, and to be normal if larger than zero. In the practical situations, however, due to various error factors (e.g., the influences due to the later-described hysteresis), the value ΔS does not become zero but is measured as a finite value even at the misfire. In this case, more or less of a margin is introduced into the decision reference for the value ΔS considering that error. In case the value ΔS becomes smaller than a positive lower limit, it is effective for avoiding the erroneous decision to decide the misfire. Here in another method, the integration period of the before top dead center period is set so longer as to correspond to the aforementioned margin of the decision reference. Then, it is also possible to decide the misfire, if the value ΔS takes zero or a negative value, and the normal combustion if larger than zero. In this case, strictly speaking, the integration period of the before top dead center period and the integration period of the after top dead center period are not equal. [0026] In case the integration periods are set to an equal duration for the before top dead center period and the after top dead center period (that is, αTDC−α 1 =α 2 −αTDC: Formula (4) of FIG. 4), the following new effects can be attained. Specifically, the gasket type pressure sensor used for the internal pressure measurement has a sensor element comprising piezoelectric ceramics. On the other hand, most piezoelectric ceramics exhibit pyroelectrcity as the temperature rises. Therefore, the pressure sensor element using the piezoelectric ceramics has a problem that the zero point of the sensor output is liable to drift when the temperature changes. FIG. 6( a ) schematically illustrates the internal pressure measured profile in a steady state (at a low temperature), and FIG. 6( b ) schematically illustrates the internal pressure measured profile in a transient state (at a high temperature). By the influences of the zero-point drifts due to the temperature, the internal pressure measured profiles are evenly shifted over the entire measurement period, if the period is so short as to cause no problem in the temperature change. If the integration periods are equally set for the before top dead center period and the after top dead center period, therefore, the influences of the zero-point drifts can be offset at the operation of ΔS≡S 2 −S 1 , so that the misfire decision can be made more accurately. [0027] In the misfire decision using the value ΔS, for effectively retaining accuracy, the difference of the value ΔS between the normal combustion time and the misfire time is as large as possible. From this viewpoint, it is effective that the ending point of the integration period set for the before top dead center period and the starting point of the integration period set for the after top dead center period are individually made identical to a top dead center αTDC, as illustrated in FIG. 4. So long as the necessary and sufficient misfire decision accuracy can be retained when the integration period of the before top dead center period is set long for the aforementioned object, however, it is possible either to join the ending point of the integration period set for the before top dead center period and the starting point of the integration period set for the after top dead center period at a position (e.g., at a position deviated to the larger angle side) other than the top dead center αTDC, or to provide a short non-integration period between the ending point of the integration period set for the before top dead center period and the starting point of the integration period set for the after top dead center period. [0028] Next, for the aforementioned misfire decision, still another correction can be made by the following method. Specifically, a second correction reference value is calculated on the basis of the internal pressure measured value of the combustion cycle (or the estimated misfire cycle) estimated in advance to be the misfire cycle, to correct the differential integrated value ΔS with the second correction reference value. [0029] This correction is made effective by the following background intrinsic to the gasket type pressure sensor. FIG. 7( a ) illustrates the results (in a solid curve) of the internal pressure measured value profile measured by the gasket type pressure sensor at the normal combustion time, in comparison with the results (in a broken curve) measured by a partition type standard pressure sensor through a pressure conduit formed in the cylinder head. It is thought that the measured values per se indicate the values more approximately from the true internal pressure. In the measurements by the gasket type pressure sensor, it is found that the profile at the pressure dropping time appears to shift to the higher pressure side than the profile at the pressure rising time. For example, FIG. 7( b ) plots the measured value P of the seated pressure sensor corresponding to a common crank angle, against a measured value P′ of a corresponding standard pressure sensor. It is found that the curves are different between the pressure rising time and the pressure dropping time thereby showing a clear hysteresis. On the other hand, FIG. 9 plots the decision index λ obtained using two gasket type pressure sensors of common specifications, against a decision index λ 0 obtained by the standard sensor. By adopting the decision index λ, the two linear curves have substantially equal gradients. It is, however, found that the values (i.e., λ hA and λ hB ) at λ 0 =0, i.e., at the misfire time indicate considerably different values due to the difference of the hysteresis. [0030] This hysteresis is thought to occur because the compressive gas forced at the pressure rising time into the thread valley or gasket of the spark plug providing the portion to be mounted in the internal combustion engine is not promptly released at the pressure dropping time but remains. In either event, it is apparent from FIG. 7( a ) that the profile at the pressure rising time is raised by the influences of the hysteresis to deteriorate the symmetry of the measured value profile curves important for the misfire decision. In the decision using the integrated values S 1 and S 2 , the integrated value S 2 of the after top dead center pressure is directly increased. It is, therefore, effective for improving the decision accuracy to correct the internal pressure measured value at the pressure dropping time thereby lessening the influences due to that hysteresis. [0031] The frequency of occurrence of the hysteresis cannot be generally estimated unless the aforementioned standard sensor is used. Only at the misfire time, however, that frequency can be determined directly from the internal pressure measured value without providing the standard sensor. Specifically, the internal pressure measured value profile at the misfire time should theoretically be symmetric with respect to the top dead center position, as indicated by a broken curve in FIG. 8. However, the profile at the pressure dropping time is raised to the extent of the hysteresis, although the misfire occurs without the hysteresis. By comparing this profile with the profile at the rising time, therefore, it is possible to estimate the rising extent of the internal pressure measured value due to the hysteresis. In other words, the rising extent of the internal pressure measured value is calculated as the second correction reference value on the basis of the internal pressure measured value of the combustion cycle (or the estimated misfire cycle) which has been found in advance to become the misfire cycle. [0032] In order to estimate the rising extent of the internal pressure measured value accurately, it is necessary to use the internal pressure measured value in the cycle which has been fixed for that at the misfire time, i.e., in an estimated misfire cycle. This internal pressure measured value ordinarily never fails to occur at the fuel cutting time for an abrupt deceleration while the internal combustion engine for an automobile is running. In case the misfire decision unit is commonly used for an ECU (Electronic Control Unit) for controlling the ignition timing or the air/fuel ratio of the internal combustion engine, for example, or in case the misfire decision unit can acquire its control information from the ECU although not used for the ECU, therefore, the misfire decision unit can grasp the occurrence of the estimated misfire cycle reliably and can calculate the second correction reference value without any problem. [0033] As shown in FIG. 8, the second correction reference value can be calculated as a value reflecting the differential integrated value S h in the estimated misfire cycle. In case the differential integrated value ΔS itself is used as the misfire deciding information, the correction may be done by subtracting the value S h or the second correction reference value from the value S 2 of the value ΔS. In the misfire decision using the aforementioned decision index λ (=ΔS/ΔP 0 ), on the other hand, the second correction reference value can use the decision index λ obtained in the estimated misfire cycle, as a correction value λ hp , and the decision index λ obtained in the combustion cycle other than the estimated misfire cycle can be corrected, in a manner to subtract the correction value λ hp . In either case, it is possible to make the accurate misfire decision, in which the influences of the hysteresis are lightened. [0034] Here, the second correction reference value can be also calculated on the basis of the internal pressure measured value in a plurality of estimated misfire cycles having occurred in the past. For example, when the increment of the internal pressure measured value due to the hysteresis is expected to be varied with the time due to the occurring timing of the estimated misfire cycle, a more reliable value of the second correction reference value can be attained by further including a statistical process such as averaging the internal pressure measured values of a plurality of the estimated misfire cycles having occurred in the past. BRIEF DESCRIPTION OF THE DRAWINGS [0035] [0035]FIG. 1 is a longitudinal section showing one example of the mounting mode of a gasket type pressure sensor; [0036] [0036]FIG. 2 is a block diagram showing one example of the electric construction of a misfire decision unit of the invention; [0037] [0037]FIG. 3 is a diagram showing internal pressure measured profiles by comparing a misfire time and a normal combustion time; [0038] [0038]FIG. 4 is a diagram explaining a method for calculating a decision index X from the internal pressure measured profile of FIG. 3; [0039] FIGS. 5 ( a) and 5 ( b ) are diagrams explaining the behaviors in which the internal pressure measured values fluctuate in levels; [0040] FIGS. 6 ( a ) and 6 ( b ) are diagrams explaining the influences of temperature drifts on the internal pressure measured profile; [0041] FIGS. 7 ( a ) and 7 ( b ) are explanatory diagrams of the hysteresis occuring in the internal pressure measured profiles; [0042] [0042]FIG. 8 is a diagram explaining the influences of the hysteresis to appearing in the internal pressure measured profile at the misfire time; [0043] [0043]FIG. 9 is a diagram plotting the behavior in which the levels of the hysteresis are made different between individual sensors; [0044] [0044]FIG. 10 is a flow chart showing the flow of a misfire deciding routine in the misfire decision unit of FIG. 2; [0045] [0045]FIG. 11 is a diagram explaining the concept of the correction value λ hp of the decision index λ; [0046] [0046]FIG. 12 is a first graph plotting the experimental results made for confirming the effects of the invention; [0047] [0047]FIG. 13 is a second graph of the same; [0048] [0048]FIG. 14 is a third graph of the same; [0049] [0049]FIG. 15 is a fourth graph of the same; [0050] FIGS. 16 ( a ), 16 ( b ) and 16 ( c ) are graphs explaining the behavior in which the influences of variations between individual sensors are lessened by corrections, and [0051] [0051]FIG. 17 is a flow chart showing the flow of a misfire deciding routine of the case in which the integrations are made by software operations. DESCRIPTION OF THE PREFERRED EMBODIMENT [0052] An embodiment of the invention will be described with reference to the accompanying drawings. However, the present invention should not be construed as being limited thereto. [0053] [0053]FIG. 1 shows one example of the mounting mode of a gasket type pressure sensor. Specifically, a spark plug 50 has a fastened thread portion 52 formed in the outer circumference of the leading end portion of a main fixture 51 . The spark plug 50 is so fastened in a thread TH formed in the bottom of a plug hole PH, by fastening the fastened thread portion 52 into the thread TH so that a spark discharge gap g may be positioned in a combustion chamber ER with respect to a cylinder head SH of an internal combustion engine configured as an automobile engine. Moreover, a flanged mounting seat 51 f is formed to protrude from the outer circumference of the main fixture 51 at a position adjoining the base end portion of the fastened thread portion 52 . On the other hand, a gasket type pressure sensor 5 has a ring-shaped sensor element 10 made of piezoelectric ceramics, which is clamped together with a ring-shaped gasket GS under a constant bias pressure in the axial directions between the mounting seat portion 51 f and an open peripheral edge portion MP of the thread TH. [0054] As a pressure in the combustion chamber ER rises, i.e., an internal cylinder pressure rises, the spark plug 50 receives the pressure in the axial directions so that the bias pressure applied to the sensor element 10 changes. As a result, the generation of piezoelectric charges in the sensor element 10 changes so that a correspondingly varying signal is extracted as a measured internal cylinder value P through an output cable CB. [0055] [0055]FIG. 2 is a block diagram showing one example of a misfire decision unit in accordance with the invention using the gasket type pressure sensor 5 . A misfire decision unit 1 has a main construction of an ECU 2 comprising a computer and executes control over such drive parameters of an internal combustion engine as an ignition timing or an air/fuel ratio, together with the misfire decision. Here, the construction and functions of the ECU 2 are well known in the art excepting the misfire deciding function to be described hereinafter, and the following description will be focused on that misfire deciding function. [0056] The ECU 2 is constructed as a computer in which a CPU 3 , a ROM 4 , a RAM 5 and an input/output interface 6 are interconnected through a bus. [0057] The ROM 4 stores a control program defining the control processing functions of the ECU 2 and having a misfire decision routine incorporated therein. The CPU 3 realizes the function of the ECU 2 by executing the control program using the RAM 5 as a work memory. [0058] A crank angle sensor 7 for detecting the crank angle of the internal combustion engine is connected to the input/output interface 6 . The crank angle sensor 7 is, for example, a pulse generator for detecting the rotational angle of the crankshaft. The pulse signal of the pulse generator is inputted to a predetermined port of the input/output interface 6 via a Schmitt trigger 8 . [0059] Moreover, the speed of the engine and the duration of one cycle can be monitored in real time with the interval of input pulses coming from the crank angle sensor 7 . [0060] Next, the pressure sensor element 10 is connected with the input/output interface 6 through a charge amplifier circuit 11 . In this charge amplifier circuit 11 , the output cable from the pressure sensor element 10 is connected with a negative input terminal of an operation amplifier 15 , the positive input terminal of which is grounded (thereby forming an inverted amplifier using ground level as a reference voltage). As a pressure is developed in the combustion chamber, the pressure sensor element 10 (FIG. 2) generates a charge. As a result, a negative feedback capacitor 13 connected with the operation amplifier 15 stores a charge balancing that generated charge, and its terminal voltage is inputted as a voltage-transformed charge signal to the negative input terminal of the operation amplifier 15 . Therefore, the operation amplifier 15 forms a charge voltage transforming circuit together with the negative feedback capacitor 13 so as to output the charge developed in the pressure sensor element 10 as an amplified voltage signal. A resistor 12 connected in parallel with the negative feedback capacitor 13 promotes the discharge of the negative feedback capacitor 13 , when the generated charge level of the pressure sensor element 10 turns negative, and prevents output saturation of the operation amplifier 15 . On the other hand, a resistor 14 on the signal line from the pressure sensor element 10 protects the terminals of the operation amplifier 15 . [0061] The output of the charge amplifier circuit 11 is inputted as an internal pressure measured value signal through a voltage follower 16 and an A/D converter 17 to a predetermined port of the input/output interface 6 . In this embodiment, on the other hand, a before top dead center pressure integrated value S 1 and an after top dead center pressure integrated value S 2 are calculated on the basis of the internal pressure measured value signal, as shown in FIG. 4, and are used to make the misfire decision. Therefore, the output of the charge amplifier circuit 11 is branched and inputted to an integration circuit 24 . [0062] In this integration circuit 24 , the branched output of the charge amplifier circuit 11 is inputted through a voltage follower circuit 18 to an operation amplifier 19 forming a well-known integrator, with which a resistor 21 and a negative feedback capacitor 20 are connected. The integrated output of the integration circuit 24 is inputted to a predetermined port of the input/output interface 6 through an A/D converter 23 . In order to clear the output of the integration circuit 24 for each cycle of combustion, a switch circuit (as exemplified by a photo-MOS relay) 22 is connected with the negative feedback capacitor 20 for earthing/discharging the negative feedback capacitor 20 in response to an action command signal from the ECU 2 . [0063] In the system of this embodiment, the integration circuit 24 integrates the output of the charge amplifier circuit 11 , i.e., the internal pressure measured value P with time t. Strictly speaking, therefore, this value is not the integrated value which is expressed by the angle α of Formulae (2) and (3) of FIG. 4. If the interval of the input pulses from the crank angle sensor 7 is measured by a clock counter, however, the prevailing engine speed, i.e., the duration of one cycle (which may be an average value of a predetermined number of immediately preceding cycles, for example) can be calculated in real time. Therefore, the time-integrated value obtained can be transformed into the integrated value by the angle α, if it is divided by the duration of one cycle. Here, the aforementioned time-integrated value can be used as it is, if the influence of the engine speed fluctuations at the misfire measuring time is low. [0064] The misfire decision processing flow will be described with reference to the explanatory diagram of FIG. 4 and the flow chart of FIG. 10 considering the case using a decision index λ (although the memories of individual variables to be used in this processing are formed in the RAM 5 of FIG. 2). First of all, the signal of a crank angle α is inputted, as shown in FIG. 2, as the pulse signal outputted by the crank angle sensor 7 and is added by the α-counter in the RAM 5 . This added value of the α-counter indicates the prevailing crank angle (although the crank angle sensor 7 could be exemplified by an absolute type pulse generator while eliminating the α-counter). At S 1 of FIG. 10, moreover, the routine is initialized by resetting the α-counter and by activating the switching circuit 22 of FIG. 2 to reset the integrated output of the integrator. After these resets, the addition of the α-counter at S 2 is started according to the execution of the cycle starting job by the ECU 2 . [0065] After this, the addition of the α-counter is continued on standby until the arrival of the sampling timing of the predetermined internal pressure measured value P and its integrated value S. Specifically, the routine is on standby at S 3 for reading the input ports of the internal pressure measured signal and its integrated value, and the α-counter is read at S 4 . At S 5 , moreover, it is judged whether or not the crank angle α indicated by the α-counter has reached a starting point α 1 (or a point for setting a first one of the aforementioned two correction measurement points in this embodiment) of the before top dead center integration period set to a period after an intake valve is closed. If this answer is NO, the routine returns to S 3 to repeat the subsequent operations. If YES, the routine advances to the operations at and after S 6 . [0066] At S 6 , the internal pressure measured value P is read in response to the arrival of the first correction measurement point and is set as the aforementioned value P 1 in the memory. Moreover, the switching circuit 22 is turned off to release the integrator from the reset state at S 7 . As a result, the integration of the internal pressure measured value P is started at and after the starting point α 1 . Then, the standby is restored again for sampling at S 8 , and it is judged at S 9 whether or not the value cc has reached the second one of the two correction measurement points. If the answer is NO, the routine returns to S 8 , at which the subsequent operations are repeated. If YES, the routine advances to the operations at and after S 10 . [0067] At S 10 , the internal pressure measured value P is read in response to the arrival of the second correction measurement point and is set as the aforementioned value P 2 in the memory. At S 11 , moreover, the aforementioned value ΔP 0 =P 2 −P 1 is calculated and set in the memory. At S 12 , moreover, the standby is made for the sampling. At S 13 , it is judged whether or not the value α has reached a top dead center angle αTDC. If the answer is NO, the routine returns to S 12 , and the subsequent operations are repeated. If YES, the routine advances to the operations at and after S 14 . [0068] At S 14 , the input value from the integrator is read. This value indicates the before top dead center pressure integrated value S 1 (of Formula (2) of FIG. 4) and is set as the value S 1 in the memory. Here, the input value from the integrator is the time-integrated value of the value P as described above. The duration T of one cycle is determined from the input pulse interval from the crank angle sensor 7 , and the crank angle α is transformed into the integrated value by dividing it with the duration T, although omitted from the flow chart. At S 15 , the standby is restored again for the sampling, and it is judged at S 16 whether or not the value α has reached the ending point α 2 of the integration period of the after top dead center pressure integrated value S 2 . If the answer is NO, the routine returns to S 15 , and the subsequent operations are repeated. If YES, the routine advances to operations at and after S 17 . [0069] At S 17 , the input value of the integrator is read again according to the arrival of the ending point α 2 . This value indicates the integrated value from α 1 to α 2 , i.e., S p =S 1 +S 2 and is set in the memory. At S 18 , the value S 2 is calculated as the value of S p −S 1 . Then, the routine advances to S 19 , at which the value of the aforementioned decision index λ is calculated by using the calculated values S 1 , S 2 and ΔP 0 . [0070] Next at S 20 , there is read a correction value λ hp for the aforementioned hysteresis correction, which has been calculated and stored in the preceding routine. At S 21 , a correction is made to calculate the final corrected decision index λ′ by subtracting the correction value λ hp from the decision index λ already obtained. At S 22 , this value λ′ is compared with a decision reference value (or an upper limit value) λ c , and the decision of misfire is made if λ′<λ c , The ECU 2 of FIG. 2 outputs a predetermined misfire decision (FIG. 10: S 23 ) from a decision output port of the input/output interface 6 . [0071] In case this cycle is an estimated misfire cycle such as a fuel cut cycle intended from the beginning by the ECU 2 , the routine advances to S 25 in FIG. 10. At S 25 , the correction value λ hp is updated by using the decision index λ before the correction, which has been obtained in that cycle. FIG. 11 shows the updating method schematically. For calculating the value λ, it is necessary to calculate a differential integrated value ΔS for each estimated misfire cycle. Here, the differential integrated value is used as a correction value so that it is expressed by ΔS h and is further suffixed into ΔS h1 , ΔS h2 , - - - , and ΔS hk so as to correspond to the time series array of the estimated misfire cycle. In a relatively convenient method, the differential integrated value is calculated as an average value Δ hm of the values ΔS h which are obtained in a plurality of (e.g., an N-number of) preceding estimated misfire cycles, as indicated by [ 1 ] in FIG. 11. [0072] By an accidental cause, on the other hand, the value ΔS h obtained in an estimated misfire cycle may take such a numerical value as extraordinarily deviates from the tendency of the preceding ΔS h . Therefore, the following method can be adopted as one for obtaining the corrected value λ hp of a higher reliability by reducing the influence of the extraordinary value. In this method, the product value of the average value ΔS hm of the values ΔS h of the just preceding N-number and the term β/(1−β) by using a correction coefficient β is used as a predicted value ΔShp of a next value ΔShi, as indicated by [ 2 ] in FIG. 11. By using the predicted value ΔS hp and the actually measured ΔS hi , moreover, a correction factor A i is calculated for each estimated misfire cycle from a Formula [3] of FIG. 11. The aforementioned correction coefficient β is calculated as an average value of the correction factors A i which have already been obtained in the just preceding N-number of estimated misfire cycles, by Formula [4] of FIG. 11. [0073] The value A i is so clarified, if modified into [ 3 ]′ by dividing the denominator and numerator of Formula [3] individually by ΔS hi , as to come closer to ½ if the difference between the result value (ΔS hi ) and the predicted value (ΔS hp ) relating to the value ΔS h becomes smaller, to 1 if the result value becomes larger from the predicted value, and to 0 if smaller on the contrary. Therefore, the correction coefficient β or the average value of the values A i also becomes closer to ½ (as will be termed into the “pattern 1 ”) as the number of cycles of smaller difference between the result value and the predicted value becomes larger in the product of ΔS h in the past estimated misfire cycles, to 1 (as will be termed into the “pattern 2 ”) as the number of cycles, in which the result value is far higher than the predicted value, becomes larger, and to 0 (as will be termed into the “pattern 3 ”) as the number of cycles, in which the result value is far lower on the contrary, becomes larger. [0074] In this case, the value of β/(1−β) approaches closer to 1 in the pattern 1 . In other words, the difference between the result value and the predicted value is intrinsically small so that the effect of correction can be reduced. In the pattern 2 , on the other hand, the value of β/(1−β) is inversely higher as the difference of the result value from the predicted value is larger. Therefore, the predicted value becomes higher toward the result value so that the correction precision is enhanced. In the pattern 3 , on the other hand, the value of β/(1−β) approaches closer to 0 as the difference of the result value from the predicted value becomes larger. In other words, the predicted value becomes smaller toward the result value so that the correction accuracy is likewise enhanced. Here, each value ΔSh can be transformed into the value λ hp by dividing it by the corresponding value ΔP 0 . In this case, a correction factor A using the λ and the correction coefficient β can be likewise calculated by replacing the value ΔS h by the value λhp in Formulae [3] and [4] of FIG. 11. [0075] Here, the aforementioned integrations can be made by a software in the ECU 2 , and the integration circuit 24 of FIG. 2 can then be omitted. It is also easily realized by processing a program to acquire the integrated value with the angle α by using the input pulse interval from the crank angle sensor 7 . One example of this processing will be described with reference to a flow chart of FIG. 17. Here, the internal pressure measured value P is read (for a measuring job) by an interrupting operation for every increment δα of the certain c rank angle α, and the added value of the values P is calculated as an integrated value. [0076] At T 1 , it is judged whether or not the crank angle α indicated by the α-ccounter has reached the timing just before a starting point α 1 of the before top dead center integration period, i.e., α 1 −δα. If the answer is NO, a standby is made while continuing the addition of the α-counter. If YES, the routine advances to T 2 , at which the integration memories S 1 and S 2 are cleared. At T 3 , the interrupt of the measured job is permitted (to release the mask of an interrupt terminal). From now on, the value P is read at each δα and is stored in an overwritten shape in the P memory of the RAM 5 (FIG. 2). [0077] The measuring job includes two steps of reading (U 1 ) the internal pressure measured value P and setting (U 2 ) a measurement end flag indicating that the reading(or measurement) of the value P has completed. In the misfire deciding main job, it is judged by confirming the contents of the measurement end flag at T 4 whether or not the value P has been updated by the latest measured value. If this answer is YES, the routine advances to T 5 , at which the prevailing crank angle α is read. If this angle α is smaller than the value αTDC, the routine advances to T 6 , at which the value P is added to the integration memory of S 1 . Moreover, it is confirmed at T 7 whether or not the value α has reached α 1 . If this answer is YES, the routine advances to T 8 , at which the prevailing value P is stored as the aforementioned value P 1 . At T 9 , the measurement end flag is reset, and the routine is returned to T 4 . After this, these operations are repeated. If it is judged at T 7 that the value α is larger than α 1 , on the other hand, the routine advances to T 10 , at which it is judged whether or not the aforementioned value αJ has been reached. If this answer is YES, the routine advances to T 11 , at which the prevailing value P is stored as the aforementioned P 2 and at which the value ΔP 0 is calculated and stored as P 2 −P 1 , (otherwise the routine skips T 11 ). After this, at T 9 , the measurement end flag is reset, and the routine is returned to T 4 to repeat the subsequent operations. [0078] If it is judged at T 5 that the value α is not smaller than αTDC, the routine advances to T 12 . If it is judged at T 12 that the value α is equal to αTDC, the routine advances to T 13 . At T 13 , the final addition of P to S 1 is made, and the addition of P to S 2 is started. The routine is returned through T 9 to T 4 . This is because the value P at αTDC belongs to both S 1 and S 2 . If the value δα is sufficiently small, the operation can be done assuming that the value P at αTDC belongs to either S 1 or S 2 . If it is judged at T 12 that the value α is larger than αTDC, on the other hand, the routine advances to T 14 , at which it is judged that the value α is no more than α 2 . If this answer is YES, the routine advances to T 15 , at which the addition of P to S 2 is continued. If NO, on the other hand, the routine advances to T 16 , at which the interruption of the measuring job is inhibited (that is, the interruption terminal is masked) to end the integrating operations and to advance to T 17 . The operations at and after T 17 will be omitted on their description, because they are similar to those at and after S 19 of FIG. 10. [0079] Here will be described the results of experiments which have been performed for confirming the effects of the invention. [0080] First of all, ten gasket type pressure sensors identical to that shown in FIG. 1 were prepared and were attached together with spark plugs to a four-cylinder gasoline engine having a displacement of 2,000 cc. This engine was run at various engine speeds by setting the ignition timing at 15 degrees of before top dead center (BTDC) and a misfire decision was made by a decision unit in FIG. 2. FIG. 12 plots the results of misfire decisions based on the value of the aforementioned differential integral value ΔS. Solid diamonds plot the average values of ΔS of the cycle decided as a normal combustion, together with their distribution ranges (as indicated by error bars). The solid squares plot the average values of ΔS of the cycle decided as a misfire, together with their dispersion ranges. According to this graph, it is implied that the decisions could be made without any serious problem for a high RPM range, but that the distributions of the values for deciding the normal combustion and the misfire were so close to each other for a low RPM range that an erroneous decision was probable. On the other hand, FIG. 13 plots similar experimental results of the case in which the misfire decision is made by using the aforementioned decision index λ. Here, the first correction measuring point was set at the integration period starting point α 1 and at a BTDC of 90 degrees, and the second correction measuring point was set at BTDC of 5 degrees after the ignition timing. It is seen, as compared with FIG. 12, that the ratio of the dispersion range to the average value of λ was reduced in a low RPM range so that the decision accuracy was improved. Moreover, FIG. 14 plots the case in which the second correction measuring point was set at a BTDC of 20 degrees before the ignition timing, and imdicates that the dispersion range ratio in the low speed range was further reduced. FIG. 15 summarizes the dispersion range ratios to the average value at every speed for the foregoing three results. It is apparent that the setting of the second correction measuring point before the ignition timing gave the most excellent result. [0081] For two different sensors, on the other hand, FIG. 16( a ) shows an example, in which the differential integration values ΔS obtained by using the gasket type pressure sensor are plotted against the differential integration values ΔS 0 obtained by using the standard sensor. Both the sensors caused generally linear changes of ΔS against ΔS 0 but a large difference in the values of the gradient and the intercept. Next, FIG. 16( b ) plots the decision indexes λ, which were obtained by dividing the differential integration values of the two sensors by the value ΔP 0 , against the similar decision indexes λ 0 which were obtained by using the standard sensor. It is found that the difference in the gradient between the two straight lines was remarkably reduced. Moreover, FIG. 16( c ) plots the decision indexes λ′, which were obtained by the hysteresis correction to subtract the correction value λ hp from the decision index λ, against the value λ 0 . It was found that the differences in both the gradient and the intercept between the two straight lines were remarkably reduced, and that a constant misfire deciding circumstance could always be realized independently of the sensors used. [0082] It should further be apparent to those skilled in the art that various changes in form and detail of the invention as shown and described above may be made. It is intended that such changes be included within the spirit and scope of the claims appended hereto. [0083] This application is based on Japanese Patent Application No. 2001-135613 filed May 2, 2001, the disclosure of which is incorporated herein by reference in its entirety.

A misfire deciding method for an internal combustion engine, which can be executed conveniently at low cost by using a gasket type pressure sensor and which can decide a misfire highly accurately and reproducibly. The internal pressure of an internal combustion engine having a spark plug mounted therein is measured by a pressure sensor (or a gasket type pressure sensor) mounted in the mounting seat of the spark plug. The measured information of the internal pressure for a period (or a before top dead center period) after an intake valve is closed and before the crank angle reaches top dead center is used as the before top dead center pressure information, and the measured information of the internal pressure for a period (or an after top dead center period) after the crank angle reaches the top dead center and before an exhaust valve is opened is used as the after top dead center pressure information. Misfire of the internal combustion engine is decided on the basis of misfire decision information obtained using the before top dead center pressure information and the after top dead center pressure information.

BACKGROUND OF THE INVENTION The present invention relates to a disk type brushless coreless DC motor, and more particularly to a disk type brushless coreless DC motor comprising a rotor made up with alternately configured N-S magnetic pole, a stator having a position-detecting sensor and a board on which more than one air cored armature coil is disposed facing the field magnet of the rotor. And more particularly, the present invention relates to a disk type brushless coreless DC motor in which cogging force is generated by the screw combining the circuit board on which armature coils are disposed with a casing member of the stator and thereby the a dead point could be eluminated. According to the growing tendency to lighter, thinner, smaller DC motors, efforts have been concentrated to reduce unnecessary parts and members of rotors and stators in DC motors. As a result of those efforts, a brushless coreless DC motor has been proposed that has dead points in which the rotational torque of the rotor becomes zero because the coil torque characteristic of the armature coil in the rotational state, so such DC motors as are shown in FIG. 1 and FIG. 2 have been provided for dead point elimination. For an example, in FIG. 1 the motor comprises a rotor made up with a rotor yoke 41 on which field magnet 42 is disposed, and a stator is made up with stator yoke 45, on which armature coil 43 is installed, and a position-detecting sensor, the stator yoke 45 being a specially structured saw tooth shape in cross section. And in the configuration of FIG. 2, an iron bar 46 is installed for cogging torque generation in armature coil 43, instead of the saw tooth type stator yoke of FIG. 1. The flux distribution produced in the illustrated relationship of rotor field magnet 42 and iron bar 46 in a stationary state is shown in FIG. 3, and the flux distribution around the dead point is shown in FIG. 4. On the other hand, another method has been suggested in Japanese Laid-open Utility Model Gazette Nos. Showa 61-192674, 61-192676, 62-2367, that eliminates dead points in DC motor by putting a magnetic substance for cogging torque generation at the other side of the armature coil board in a various forms in brushless coreless DC motor. With this method, the cogging torque is to be generated at the position of 22.5° with a rotor with a 4 pole field magnet, 15° with a rotor with a 6 pole field magnet, and 11.5° with a rotor with an 8 pole field magnet; i.e., cogging torque is to be generated at 1/4 position of magnetic pole width. Accordingly the combined torque curve of a rotor in which a 4 pole magnet is attached becomes as in curve (a) in FIG. 5. This combined characteristic curve represents the ideal state, where (b) represents the torque curve by armature coil, and (c) represents the cogging torque curve. In the above methods, however, the technique of FIG. 1 involves difficulties in production because it requires a special saw tooth shaped yoke facing the field magnet of the rotor for dead point elimination, so it turned out not to be a desirable method, and also because of a peeling off problem of the coil, occurring in the assembling the process of armature coil relative to the upper face of the rotor yoke, which resulted in an increased error rate. In the case of the technique of FIG. 2, a specially structured iron bar is to be put and held inside of the air cored armature coil, which involves difficulties in production, so this method also turned out not to be a desirable one. In addition, in the case of the preferred method disclosed in Japanese Laid-open Utility Model Gazette No. Showa 61-192674, 61-192676, and 62-2367, the separate stator yoke is to be specially cut and installed on the back side of a circuit board, so this method also turned out not to be a desirable one because of the complicated structure requiring a separate stator, yoke and accompanying difficulties in production. Especially in this method, insulation between circuit board and stator yoke is essentially required, thus the process becomes complicated with increasing cost. Thus the prior art described above required special structures for dead point elimination in a brushless coreless DC motor, resulting in an increase in the number of components or complexity, which involved an increase of size and price, so it turned out not to be desirable. SUMMARY OF THE INVENTION It is an object of the present invention to provide a brushless coreless DC motor which does not require a specially structured stator yoke or increase the number of parts for dead point elimination. It is another object of the present invention to provide a brushless coreless DC motor which, requiring no additional parts or special structure, will make it possible to maintain ease of production, low price, and light weight. The present invention is characterized by the configuration in which the single screw, which is used to assemble and hold the circuit board of the stator inside the stator case, is to be installed at a selected specific position on the board for dead point elimination. Further objects and advantages of the present invention will be apparent from the following description of the preferred embodiments of the present invention as illustrated in the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an example of a cogging torque generation method in conventional brushless coreless DC motors. FIG. 2 is the illustration of another example. FIG. 3 shows the magnetic flux distribution of the rotor of FIG. 2 in a stationary state. FIG. 4 shows the magnetic flux distribution of the rotor of FIG. 2 produced by the cogging torque around the dead point. FIG. 5 is a graph showing the traditional ideal combined torque curve. FIG. 6 is cross-sectional view of an example of a disk type brushless coreless DC motor according to the present invention. FIG. 7 is a perspective view of the rotor case of the motor shown in FIG. 6 FIG. 8 is schematic diagram of the hole positions for rotor screw insertion according to the present invention. FIG. 9 is a graph showing the combined torque curve of the rotor in a motor according to the present invention. FIG. 10 is a graph showing a characteristic curve of the starting voltage and starting torque in a motor according to the present invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments of a brushless coreless DC motor in accordance with the present invention will now be described in detail with reference to the accompanying drawings. FIG. 6 illustrates an example of a DC motor according to the present invention, wherein the central part of the rotor body 21, to the outside of which fan 21a is integrated, is coupled to the shaft 22 rotatably received in the shaft support 15 at the center of stator 17, and a ring shaped field magnet 24 and a rotor yoke 23 are disposed in and secured to the insdie of the rotor body 21. And the circuit board 12, on which both an armature coil 16 facting the rotor field magnet 24 and a position-detecting sensor 14 are installed and secured, is to be secured on the support 13 projecting from the bottom of the stator case 17. Here, a single screw is used to assemble and hold the board 12 to the support 13. Preferably, as shown in FIG. 8, the hole 18 on the board 12 through which the screw 11 passes is to be drilled at a position, said Q1, to which the open angle from the position-detecting sensor. 14 becomes 1/5 (18° in the 4 pole case) the pole width of armature coil 16 and field magnet 24, so the screw 11 as a cogging generator is inserted and tightened to the support 13 through the hole 18 drilled in the circuit board 12 at the preferred position. The position-detecting sensor 14 is to be installed and secured below the effective coil part of the armature coil 16. If the screw insertion position is preferred position Q1, rotor body 21 rotates clockwise, and if the position is P1, rotor body 21 rotates counterclockwise. Q1-Q4, and P2-P4 represent positions where the screw 11 may be inserted, and are obtained from the following formula. Q1(P1)±nπ/2(n=0, 1, 2 . . .) or 1/5 of the magnetic pole width ±2nπ/N (n is a non negative integer, and N is the number of poles) and it is desirable for the single screw 11 to have a round shaped head. FIG. 7 depicts an example wherein the single support 13 for receiving the screw 11 protrudes at the specified position from the inside of the stator case body 17. The operation and advantages of this embodiment of the present invention are described as follows. Referring to FIG. 6, FIG. 7 and FIG. 8, the stator is formed by inserting the screw 11 through the hole 18 at the Q1 position on the board 12 on which a pair of armature coils 16 are installed, to the support 13 formed at the inside of the bottom of stator case 17, the rotor body 21 is coupled on the shaft 22 rotatably carried in the stator case 17, the armature coil 16 is energized and then the brushless coreless DC motor starts rotating by the operation of the control circuit (diagram omitted) according to the position-detecting signal from the position-detecting sensor 14. At that time, the dead points are eliminated by the cogging torque generated by the head part of the screw 11 disposed at the 1/5 point of the magnetic pole width (18° in the case of 4 poles), so the rotor body rotates clockwise. The same cogging torque and rotational torque in the same direction as above are obtained regardless which one of the Q2-Q4 positions derived from the above formula (1/5 of the magnetic pole width ±nπ/2) is selected instead of Q1 for the screw insertion position. The variable selection of the position like this gives the advantage of avoiding damage to armature coil 16 that may occur in the screw 11 insertion process when the inner diameter of the armature 16 coil is small. Also, the same cogging torque as mentioned above is obtained when the screw 11 is installed at the P2 position, but in this case the rotor body 21 rotates counterclockwise. In this case also, the same cogging torque and rotational torque to in the same direction are obtained as long as any one of the P1, P3, P4 positions is selected for the screw insertion position. FIG. 9 shows the combined torque curve (a) of the torque curve (b) by the armature coil 16 and the cogging torque curve (c) by the screw 11 positioned according to the present invention. And in case the pole number for the field magnet of the rotor is different, the installation position of the screw 11 could be found with the above formula (1/5 of the magnetic pole width ±2nπ/N). On the other hand, the round shaped head used for the screw head concentrates the magnetic flux from the field magnet 24 facing the screw. 11, and enables the screw head to always be placed at the center of the magnet pole width, thus eliminating dead points by providing cogging torque. FIG. 10 shows the characteristic graph of starting voltage and starting torque that vary according to the cogging torque generation position, wherein area A represents the useless mechanical angle in which intallation of the screw is difficult for cogging torque generation, area B represents the range in which generated cogging torque is too small to start (i.e., a dead point), and area C represents the practically usable range. Accordingly, when the cogging torque generation position is set to 18° as in the mentioned example, it is noticed in accordance with the starting voltage curve 200 that the DC motor can be started with a starting voltage of about 3 V, which is a lower value compared to a conventional motor, for which the cogging torque generation position is set to 22.5°, and a starting voltage of 8 V is required. Also, in the case where the cogging torque generation position is at 18°, the starting torque curve 100 shows that a starting torque of about 19 g-cm is generated a much larger value that contrasts with a starting torque of 12.5 g-cm generated in a conventional motor where the position is 22.5°. Further, as is shown in the graph of FIG. 10, when the cogging torque generation position is set to anywhere, between 15°-18°, flat starting torque and starting voltage characteristics are obtained. Furthermore, as the cogging torque generation position moves from 18° to 10°, it is possible to obtain an improved starting torque and starting voltage. As has been pointed out hereinabove, the present invention eliminates dead points without any separate parts of special structure and with only a single assembling screw in a brushless coreless DC motor including a position detecting-sensor, which enables to easy production, low cost, and especially light weight. Many widely different embodiments of the present invention may be constructed without departing from the spirit and scope of the present invention. It should be understood that the present invention is not limited to the specific embodiments described in the specification, except as defined in the appended claims.

The present invention relates to a disc type brushless coreless DC motor which includes a rotor and stator. The DC motor includes a position-detecting sensor installed and secured below an effective coil part of an armature coil, and a single screw having a rounded head is installed at the position 1/5 of a magnetic pole width ±nπ/2 apart from the position-detecting sensor along a clockwise (or counter clockwise) direction when the rotating direction of the rotor is counter clockwise (or clockwise), thereby permitting the achievement of easy production, low cost, and especially light weight, and, further, larger starting torque with a lower starting voltage in the DC motor.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to collapsible cores. More specifically, this invention relates to collapsible cores useful in the molding of threaded plastic closures. Still more specifically, this invention relates to collapsible cores useful for molding threaded closures in which the threads are in the form of a plurality of thread segments. It is also useful for other undercut products. 2. Description of the Prior Art In the prior art there are a number of patents showing collapsible cores used in making threaded closures. By means of such collapsible cores it is not necessary once a threaded cap, for instance, is molded to "unscrew" it from its core; instead the core is collapsed and the threaded closure is simply stripped off the collapsed core. Some examples in the prior art include, for instance, U.S. Pat. No. 3,618,170, E. W. Owens, granted Nov. 9, 1971, which shows a collapsible core presenting a pair of core portions which are held in proper molding relation by an actuator, the sides of which have non-threaded segments. Once the closure is molded, the actuator is withdrawn and the portions of the core are permitted to collapse inward so that the closure may be readily stripped. Another example of a collapsible core is disclosed in U.S. Pat. No. 4,019,711 to J. Altenhof et al which issued Apr. 26, 1977. In this patent a plurality of thread-molding segments ride in grooves on the core. These segments have threaded sides. Once the closure is molded, the segments will move longitudinally of the core on a incline so that when the segments are fully extended, their diameter is reduced and the closure may be stripped to provide a closure having segmented threads. A still further example of a collapsible core is shown in the U.S. Pat. No. 4,130,264 to Schroer which issued Dec. 19, 1978. In this patent there are a plurality of segments about the periphery of the core. The segments, once the molding is complete, move on tracks at different inclinations so that the core, when collapsed, may be easily stripped. The product in this instance is a closure having threads on its inside all the way around. SUMMARY OF THE INVENTION Under the present invention the male member comprises a body having an upstanding cylindrical core, with a tapered seat inbetween the body and core. The core, seat and body are intercepted by a plurality of cylindrical bores uniformly disposed about the center axis. Blades having cylindrical bodies ride in the bores and are shaped in the area of the tapered seat and cylindrical core to form components which continue those shapes. The blade components may have thread segment matrices on their outer surfaces so that the final closure has interrupted interior thread segments. There are advantages to the structure now presented. Because the bores and bodies of the blades are cylindrical, there is great precision in the positioning of the blades. This precision is enhanced by the presence of a stripper bushing which has a tapered bore having an inner surface comforming to the tapered seat so that when the bushing is in place, it holds the blades exactly where they should be. In addition, because the cylindrical bores can incline toward the axis steeply and still guide the blades firmly, the stroke of the blades from molding position to collapsed position can be quite short. This will use up less room within the mold platens than the collapsible cores of the prior art. Thus, under the present invention the shortness of the male mold member and its movement make possible a "stacking" of a plurality of molding units between the platens of the mold press. BRIEF DESCRIPTION OF THE DRAWINGS Other features and objects of the invention will be apparent from references to the accompanying drawings and the specification including claims, all of which disclose a non-limiting embodiment of the invention. In the drawings: FIG. 1 is a perspective view from above of a male mold member including the body and core embodying the invention and is shown in molding position; FIG. 2 is a view similar to FIG. 1 but showing the blades extending so that the member is in collapsed condition; FIG. 3 is a prospective view taken from underneath the member and showing the member in collapsed position and a closure C having been stripped from the member; FIG. 4 is a sectional view taken on the line 4--4 of FIG. 1 and including the stripper bushing in place; FIG. 5 is a top view of the mold member in the position shown in FIG. 4 with the stripper bushing removed; FIG. 6 is a sectional view similar to FIG. 4 but showing a blade extended as when the member is collapsed and showing the withdrawn stripper bushing; FIG. 7 is a top plan view of the core collapsed as in FIG. 6 but with the stripper bushing removed; FIG. 8 is a sectional view through the parts of a mold base including the collapsible member of the invention and showing the mold member in molding position; FIG. 9 is a sectional view similar to FIG. 8 but showing the base broken open between the core and cavity; and FIG. 10 shows the mold base all the way open, but for simplicity, not showing the various stripper bolts, leader pins and bushings, etc. DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more specifically to the drawings, a collapsible mold member embodying the invention is generally designated 10 in FIG. 1. It comprises a body or base 12, cylindrical in shape having a head 14. The body is stepped inward at its upper end to present a tapered riser 16. The body presents a front face 18 from the center of which extends upwardly a core 20. Intermediate the core 20 and the body 12 is a tapered seat 22. As shown, the body 12, seat 22 and mold member part 24 of the core are intercepted by cylindrical bores 26 which extend from the bottom of the body (FIG. 3) upward out through the face 18 and scooping into the seat 22 and the core part 24. The bores 26 have respectively disposed therein blades 28 having cylindrical bodies 28a. At their outer ends the blades are reduced in their outer dimension to present shoulders 29 and have sections 30 which conform with the shape of the cylindrical core 24 and the seat 22. On their exterior surface the blade sections 30 are formed with grooves 32 which comprise the matrices for thread segments. (The resulting threads appear in the final closure product as segments of threads T (FIG. 3).) As shown best in FIG. 4 the cylindrical bores 26 incline from the back 15 of the base body inwardly toward the center axis A of the core (FIG. 4). As a result, when the blades 28 are extended (FIGS. 2, 3 and 7), the core collapses, that is, the outer effective diameter of the blade components 30 in the cylindrical area 24 is reduced so that the molded closure C can be readily stripped therefrom. The molded closure as shown in FIG. 3 is a cap C which has thread segments T formed inside the cap alternating with non-thread segments, all reflecting the configuration of the composite cylindrical core 24 including the blade sections 30. The stationary parts of the core 24 (between the blade sections 30) are not formed with any thread matrix 32. The male mold assembly includes helper springs 36 which are disposed in recesses 38 inside the cylindrical bodies of the blades. Guide screws 40 are disposed in threaded openings in the side of the body and have reduced ends 40a which ride in slots 42 in the blades 28 respectively. The guide screw 40 and slot 42 arrangment assures that there will be little rotation of the blades 28 as they move in and out. when the male mold member is in molding position (FIG. 4) it is snugly surrounded by a stripper bushing 46 which has an inner face 48 which seats against the face 18 of the mold member. The stripper bushing 46 has an outward mounting head 49 and a bore opening 50 which is tapered to exactly complement the seat 22 on the member. As a result, when the core is in molding position and the stripper bushing 46 is tight against the face 18 of the mold body, it forceably contacts the tapered seat 22, assuring absolute correct orientation and immobility of the blades 28 in the core 24. As shown in FIG. 4, the member 10 may be cooled by liquid passing through a central recess 54 which is stepped down as at 56 in the front end of the core. A coolant supply tube 58 extends into the recess 54 on its axis so that coolant liquid may be supplied therethrough and circulate in the recess 54, 56 to discharge out opening 60 in the bottom of the body. OPERATION OF THE MOLD FIGS. 8 through 10 show the operation of the member 10 in a mold base. In the drawings, to keep things simple, there are not shown the conventional and well known leader pins and bushings which support the various mold plates and along which they slide or by which they are guided when the mold is opened or closed. The base is shown in FIG. 8 and generally designated 100. It comprises a bottom backup plate 110 which is bolted to the back platen (not shown) of the press. Bottom backup plate 110 is formed with channels 112 and 114 respectively which provide the inlet and outlet for cooling fluid. As shown, the inlet 112 communicates through a port 116 to tube 58 which enters the recess 54 in the member 10 as described. Outlet from recess 54 communicates with appropriate seals through passage 118 to the outlet 114. A core plate 120 is provided with an opening 122 having an annular enlargement 124 at its lower end. The core plate 120 surrounds the mold member 10 and clamps at against the bottom backup plate by bolt means (not shown). A stripper plate 130 is similarly provided with a bore 132 to accept the stripper bushing 46. The stripper plate 130 is bolted by means (not shown) to the stripper backup plate 140 to clamp the head 49 of the stripper bushing 46 therebetween. On the upper side of the mold base there is the top backup plate 150 which is bolted to the front platen of the press (not shown). An opening 152 in the top backup plate has secured therein the nozzle block 156 accepting the nozzle of the plastic injection machine. A sucker pin 158 is mounted in the top backup plate 150 and extends through an opening 162 in a sucker plate 160. A small head 164 having an undercut is disposed on the end of the sucker pin 158. Adjacent the sucker plate 160 is a runner plate 170 to which is secured by means not shown a cavity plate 180. The cavity plate 180 is provided with a bore 182 to accept a cavity or the female member 190 of the mold. The female member is clampingly held by its head 192. The female member is formed with a cavity bore 194 which communicates with a sprue channel 196 communicating in turn with a runner channel 198. The female member or cavity 190 may be formed with a peripheral cooling channel 200 which is sealed on either side by an "O" ring received in a peripheral groove as shown. A cooling water inlet 202 and outlet 204 communicate with the channel for cooling purposes. Finally, a spring button 206 is provided in the face of the cavity plate 180. It is urged by the spring 208 against the stripper plate 130. The recess in which the spring 208 is disposed extends partly in the runner plate 170 and partly in the cavity plate 180. The button 206 has a flange on its inner end to retain it in the cavity. The operation of the apparatus will now be described. With the mold base closed the plastic is injected through the nozzle 156 into the runner channel 198, through sprue channel 196 and into the cavity bore 194 surrounding the core 24. The plastic in the cavity is then permitted to cool. After setting is complete, the press is opened. The mold first breaks at A (FIG. 9) as the spring button 208 forces a separation between the cavity plate 180 and the stripper plate 130. Because the inside of the molded closure C has threads T involving undercuts, the closure is held to the core by the thread matrices 32. The outside of the closure, having no undercuts, slips easily out of the cavity bore 194. Thus the closure stays with the core in this initial break. The plastic sprue, of course, breaks away from the closure and remains in the runner plate for an instant. The mold next breaks at B (FIG. 9) causing the separation of the sucker plate 160 and the runner plate 170. Because the sucker pin holds the runner, the sprue plastic moves with the plate 160 and slips out of its channel 196 in the cavity plate. Thereafter (for an instant anyway) the runner and sprue are supported in place by the head 164 on the sucker pin 158. Next the mold base breaks at C (FIG. 9) after the break at A has progressed to a point at which it approximates the space shown in FIG. 10. The break at C is between the core plate 120 and the stripper backup plate 140. As the parts separate at C the two plates 130 and 140 carry forwardly with them the stripper bushing 46. The narrower leading end of the opening 50 in the stripper bushing engages the closure C by its open end to push it away from the core. Because of the engagement of the threads in the closure C with the undercuts on the blade components (FIG. 5) this forward movement carries with it the blades 28. As explained, the forward movement of the blades 28 along their paths inclined with respect to the center axis A collapses the blades 30 toward the axis of the male mold member. As shown in FIG. 10, the collapse of the blades eliminates the interference of the threads in the closure and the thread matrices on the blade components 30 so the closure may be stripped from the blades. The forward movement of the blades 28 is achieved not only by the urging of the stripper bushing 46 on the closure C but also by the helper springs 36 which are under compression within the bores 26. As shown (FIG. 10) the guide screw 40 limits the forward movement of the blades. In the final step of opening there is a break between the top backup plate 150 and the sucker pin stripper plate 160 at D (FIG. 9). This relative movement causes partial withdrawal of the sucker pin 158 from the stripper plate and sprue and causes the head 164 on the sucker pin 154 to pop out of the runner. The runner, being free with its attached sprue is permitted to fall out of the mold. In final open position the various plates, mold member and cavity of the mold are as shown in the FIG. 10. As stated, this FIG. does not include the various leader pins and bushings, and stripper bolts by which the mold plates are laterally supported and horizontally moved. It should be understood that in a present embodiment the mold member of the invention is used in a 4-cavity mold. The present drawings show only a single cavity of this embodiment. This is why the drawings of FIGS. 8 through 10 appear unsymetrical. Once the closure C has been stripped off the collapsible core 10 and the sprue and runner are removed (FIG. 10), the mold may be reclosed for its next cycle. The two press platens (not shown) are forced together and the mold, when closed, appears as it does in FIG. 8. In this closing process the stripper bushing 46 moves the blades 28 to the retracted position against the bias of the helper springs. As the mold is closed, the leftward face of the stripper bushing engages the flat shoulders 29 on the end of the blades 28. In final closed position of the mold, the blades 28 are in their retracted position and immobilized by the stripper bushing 46. The tapered bore 50 of the bushing engages and properly orients the blades 28 as it presses against the portions of the tapered seat 22 which are on the blades. It should be understood that the guide screw 40, to some extent, assures proper rotary orientation of the blades 28, but the exact rotary positions of the blades is assured by the firm seating of the tapered bore 50 against the tapered seat 29. With the mold thus closed, plastic is shot through the nozzle 156 along the runner 198 through the sprue channel 196 and into the cavity bore 194 for beginning of the next cycle. It should be clear from the above description that the collapsible core of the invention is characterized as having a short stroke and hence there is less need for great room in the opening of the press as with earlier collapsible cores. Further, the proper orientation of the core blade 28 is achieved in an especially effective way as the stripper bushing 50 itself seats on the tapered seat 22. Variations of the invention are contemplated and hence the invention should not be thought of as limited to the specific embodiment shown. Rather it should be thought of in terms of the following broad claim language and reasonable equivalents thereof.

A male mold member includes a base or body having a central projecting core with an intermediate peripheral tapered seat between the core and body. The body, seat and core are intercepted by a plurality of cylindrical bores spaced uniformly about the male mold member and inclined toward the core axis. The bores receive core blades having cylindrical bodies. The core blades are exteriorly shaped in the area of the core to form sections which continue the contour of the core and seat. The blades may each have a thread matrix in the core area. After molding, a stripper bushing, engaging the molded product, pushes the product along with the core blades to a position at which the core blades are collapsed so that the product may be stripped. In the molding position the stripper bushing has a tapered bore opening which fits snugly against the tapered seat portions on the blades to orient the blades to proper position and immobilize them.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for the combustion of large particles. 2. The Prior Art As early as in 1961 F. H. Reynst mentioned that it was known that acoustic vibrations have a beneficial effect on combustion. In this connection reference is made to Pulsating Combustion, pp 13-15, The Collected Works of F. H. Reynst, Pergamon Press, New York 1961. Although the vibrations may be only very weak, the relative motion of the gas with respect to the fuel particle which results is sufficient to remove the envelope of combustion products around this particle, resulting in an increase of the combustion rate. Reynst describes the application of this principle to a pulverized coal burner. A mixture of fuel and air is delivered by a fan to a precombustion chamber located between two conical passages flaring in the direction of flow. Volatile components of the fuel are combusted in the precombustion chamber, and the flame is directed into a flame tube. The pulsations of the flame in the precombustion chamber are propagated into the flame tube wherein the column of gas is set in resonance so as to move relatively with respect to the fuel particles, which speeds up the combustion as mentioned above. Swedish patent specification No. 7701764-8 (publ. No. 412 635) describes a method of combusting atomized solid, liquid or gaseous fuels, which is based on the principle mentioned by Reynst. However, according to this patent specification the vibrations are not generated by the burner flame. Sound energy is supplied to the combustion flame by external means such as a sound emitter, the frequency of the sound ranging from infrasound frequencies to ultrasound frequencies. However, the method of the Swedish patent specification No. 7701764-8 apparently has not yet been utilized practically to any significant extent, which may indicate that it has not been possible so far to develop the method for industrial application. Similar methods are described in Swiss Pat. No. 281,373 and German Pat. No. 472,812. According to the Swiss patent, vibration is imparted to at least part of the combustion chamber and the flue gases, and according to the German patent, a dispersion of particulate fuel and combustion air as well as secondary combustion air is brought to oscillation. The USSR Author's Certificate No. 228,216 (V. S. Severyanin) describes a pulsating combustion in a bed whereby the hot grid of the Rijke tube is replaced by a layer of solid fuel in which free oscillation will develop. The effect obtained is, however, relatively low, because only self-generated oscillation is utilized. U.S. Pat. No. 1,173,708 describes a method for burning fuel wherein the particles of a fuel bed laying on a grate are agitated by pulsating combustion air supplied from below through the grate. The particles of fuel are suspended and floated by the air and are permitted to settle in the time intervals between the pulsations. SUMMARY OF THE INVENTION The primary object of the present invention is to provide a combustion method which further improves the beneficial effect of sound on combustion and which can be industrially applied in a practical manner and especially without the necessity of particulating the fuel to be combusted. According to the invention, a high particle velocity sound is used to provide a reciprocating movement of combustion air and combustion gas through a bed of solid fuel particles on a grate, the high particle velocity sound having a maximum frequency of 60 Hz and a wavelength which is greater than twice the dimensions of the grate in a plane which is transverse to the reciprocating movement of the combustion air and combustion gas. The high particle velocity sound is created by a low frequency generator which preferably includes a tubular resonator. The grate can be located in a chamber to which the tubular resonator is connected, or in a chamber which is located along the length of the tubular resonator. For an explanation of the invention in more detail, reference is made to the accompanying drawings which disclose several embodiments of the invention. DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic vertical cross-sectional view of a combustion apparatus according to the invention with a quarter-wave resonator, FIG. 2 is a diagrammatic vertical cross-sectional view of a combustion chamber according to the invention in one embodiment thereof, FIG. 3 is a view corresponding to FIG. 2 of a second embodiment, FIG. 4 is a view corresponding to FIG. 2 of a third embodiment, FIG. 5 is a view corresponding to FIG. 2 of a fourth embodiment, FIG. 6 is a vertical cross-sectional view of a constructive embodiment of a combustion chamber according to the invention of a half-wave type, FIGS. 7 and 8 are diagrams illustrating the conditions obtained in the combustion chamber of FIG. 6, FIG. 9 is a diagrammatic vertical cross-sectional view of a combustion chamber according to the invention, with a three-quarter wave resonator, and FIG. 10 is an elevational view of a constructive embodiment of a combustion chamber embodying the principles illustrated in FIG. 9. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, a tubular resonator 25, closed at one end and open at the other end, the length of which is a quarter of the wave length of the sound emitted together with a feeder 26, herein termed exigator for the purpose of this specification, forms a low frequency sound generator, the exigator being connected to a supply conduit 27 for driving gas. The generator can be of the positive feedback type described in U.S. Pat. No. 4,359,962. However, any other infrasound generator can be used for the purpose of the invention. The maximum frequency of the sound should be 60 Hz, preferably the maximum frequency should be 30 Hz; however, 20 Hz or less would be optimal. The resonator has a curved open end portion 28 supporting a grate 12 mounted in the opening or closely above. The grate supports a bed 13 of large solid fuels, comprising coal, peat, wood, chips, trash, etc. A tube 29 connected to a compressor or blower opens into the curved portion below the grate for the supply of combustion air. When the generator is operating, a high velocity of reciprocating air, termed particle velocity, is obtained at the opening of the resonator where the grate is located. The resonator tube can be flared towards the opening thereof to form a diffuser, but the dimensions of the area of the grate, exposed to the interior of the resonator tube, in a plane transverse to the axis of the tube at the opening thereof, should be less than half the wave length of the sound generated by the sound generator. Then, there is obtained a high velocity reciprocating movement of combustion air and combustion gas through the fuel bed and the grate under the influence of the low frequency sound. Under the influence of the high velocity of the reciprocating air combustion will be more intense, such that the content of unburnt gases and solid particles in the smoke will be reduced and the combustion rate increased. The invention can also be applied to combustion chambers for the combustion of large solid fuels. When such fuel is combusted the fuel must stay in the combustion chamber for a period sufficiently long for the burning out of the fuel lumps. A chamber for this purpose is diagrammatically shown in FIG. 2 wherein the combustion chamber 30 is connected to a low frequency sound generator 31 at the opening of the resonance tube thereof. The sound generator also in this case can be of the type described in the patent referred to above. In the combustion chamber 30 a grate 12 is arranged close to the opening of the resonance tube, and the combustion chamber 30 has a shaft 32 with a sluice, not shown, for the supply of fuel at the top of the combustion chamber. Also an inlet 33 is arranged at the top of the combustion chamber for the supply of combustion air while an outlet 34 for flues is arranged at the bottom of the combustion chamber below the grate 12. The low frequency sound generator can be connected to the top of the combustion chamber as shown in FIG. 3. However, in the embodiment of FIG. 3 the grate 12 must be located in the uppermost portion of the combustion chamber 30 to be close to the opening of the low frequency sound generator 31. Problems may arise due to the fact that the space for the fuel supplied to the grate will be restricted when the grate is arranged in this manner. This problem can be overcome by providing the combustion chamber 30 with a passive resonator below the grate 12 as shown in FIG. 4. In FIG. 4, a "passive" resonance tube 35 having a length which equals a quarter of a wave length, is connected to the combustion chamber 30 below the grate 12 at one side of the combustion chamber, the sound generator being connected to the combustion chamber at the same side thereof but above the grate 12. Also in this case there is a shaft 32 for the supply of fuel, a conduit 33 for the supply of auxiliary air as a supplement to that originally used for driving the sound generator 31 and then used as combustion air, and a flue gas outlet 34. The passive resonator 35 consists of a resonance tube closed at the outer end thereof, and due to the arrangement of this resonator the particle velocity will be substantially equal in all parts of the combustion chamber. Also the sound pressure will be substantially equal in the entire combustion chamber, however, lower than in case of no passive resonator being engaged. An air volume will reciprocate not only at the opening of the low frequency sound generator but also at the opening of the passive generator and large air and combustion gas movements through the grate will occur as a consequence thereof, the combustion being intensified by such movement in the manner previously described. The combustion chamber may be provided with heat absorbing walls. For example, the walls of the combustion chamber can be arranged for the circulation of water therein and water tubes in any previously known arrangement can be provided inside the combustion chamber by applying known techniques. However, it may be necessary to cool further the flue gas. If the flue gas is discharged from the combustion chamber through the opening of the passive resonator as shown in FIG. 5 wherein the flue outlet 34 is arranged in the wall of the passive resonator 35, the operation thereof will not be disturbed. Since the gas temperature in the resonator of the low frequency sound generator is not the same as the gas temperature in the passive resonator, the two resonators must be dimensioned with regard to different temperatures. However, during operation the temperature may vary and in order to tune the one resonator to the other at each time, one resonator, e.g., the resonator of the sound generator, could be provided with a bellows system 36 such that the length thereof can be adjusted, as shown in FIG. 5. The bellows system in this arrangement should be provided with an adjustment mechanism which is operatively connected to a pressure sensor 37 at the closed end of the passive generator for adjustment of the length of the bellows system and thus the length of the resonator of the sound generator 31 responsive to the sound pressure at the closed end of the passive resonator 35 such that the resonator of the sound generator at any time will have the optimum length for maximum effect. If the dimensions of the combustion chamber are related to the wave length such that they are less than half the wave length, the resonator tubes together with the combustion chamber can form one resonator. In FIG. 6 the resonator 31 is of the half-wave type being closed in both ends. The grate 12 is located in the longitudinal centre of the resonator where a particle velocity antinode is situated. In that part of the resonator where the grate is situated the resonator is expanded to suite a proper design of a combustion chamber. The combustion air can be supplied to the combustion process through a positive feed-back exigator of the type described in the U.S. Pat. No. 4,359,962, thereby simultaneously serving as drive gas for the exigator. The exhaust of the flue gases can be achieved in an analogical way through an exigator of the same type although in this case operating on negative feed-back. The curves of FIG. 7 show the amplitudes of the sound pressure and the particle velocity, respectively, in cold state. The node of the sound pressure p and the antinode of the particle velocity u are situated at the longitudinal centre of the resonator. The curves given in FIG. 8 show the amplitudes during operation, i.e. in hot state, where the temperature of the flue gas causes the node and antinode, respectively, to move away from the longitudinal centre of the resonator. Therefore, to achieve that the grate is situated at the antinode of the particle velocity, the colder part of the resonator (where combustion air is introduced) is made shorter than the warmer part of the resonator (where flue gas is exhausted). A practical problem is to drive an exigator with flue gas, the gas being hot and possibly contaminated with dust. To overcome this, the resonator is extended to form a three-quarter wave resonator closed in one end and open in the other. From the open end the flue gas can be exhausted in a conventional way without employing an exigator. This arrangement is shown in FIG. 9 where the colder part of the resonator is shorter than half the length of the warmer part and adjustable to its length to facilitate that the antinode is located properly. The three-quarter wave resonator will not operate at its first harmonic unless it is connected to a compensation cavity simulating an approximately free sound wave propagation. The standing wave in the three-quarter wave resonator is maintained by pulses of pressurized gas fed into the closed, in this case the colder, end thereof. It is thereby a necessity that these gas pulses have the frequency of the first harmonic of the resonator. One way of securing this is to employ a positive feed-back exigator previously mentioned. At the longitudinal centre of the warmer part of the resonator the particle velocity is at minimum and as a consequence thereof dust and other solid particles entrained in the flue gas passing through the resonator will fall out. Therefore, the resonator at this point is enlarged to form a knock-out box 39 from which the dust and other solid particles are collected in a container 40. FIG. 10 discloses a practical constructive embodiment of the system principally discussed above with reference to FIG. 9. In this embodiment, an exigator 50 of the type described in U.S. Pat. No. 4,359,962 is employed. The pressurized air is provided by a blower 51 which is connected by a conduit 52 to the exigator 50. A tube section 53 at one end of which the exigator is located, is connected at the other end thereof to a cylindrical vertical combustion chamber 54 at the top thereof. At the bottom the combustion chamber is connected to another tube section 55. In the cylindrical combustion chamber 54 two grates 56 and 57 are arranged substantially at the centre thereof one above the other. These grates are shown herein as conventional flat grates, but they can also be of other types. For example, they can be of the pyramidical type or they can be replaced by a single grate which extends helically from an upper level to a lower level. A feeder 58 is connected to the top of the combustion chamber for the supply of large pieces of fuel, the feeder having a sluice 59 for feeding fuel portions intermittently into the combustion chamber. The combustion air is supplied by the blower 51 through the exigator 50 and auxiliary combustion air is drawn into the combustion chamber 54 through a trottled inlet 60 by the negative pressure inside the chamber. At the bottom of the combustion chamber an ash container 61 isolated by a slide door 62 is provided for the collection of the ashes. The tube sections 53 and 55 form together with the combustion chamber 54 a three-quarter wave resonator, the open end of which is connected to a compensation cavity 63. This cavity can be provided with means for discharging dust and other solid particles falling out therein, although such means are not shown herein. Close to the bottom of the compensation cavity 63 a flue duct 64 connects to an exhaust fan 65 for discharging the flue gas to the atmosphere through a chimney 66. The combustion chamber 54 is provided with a water jacket for circulating water which takes up heat generated in the combustion chamber, and also the resonator tube section 55 is provided with water jackets 67 and 68 for cooling the flue gas when passing through the resonator in order to recover the heat contained therein. In the set up shown in FIG. 10, totally 300 kg black coal was combusted during 6 hours. The average power obtained was 349 kW. The flue gas in the chimney had a very low content of dust and other solid particles. This is a remarkable observation, because when black coal is combusted in furnaces and boilers of conventional design, the content of dust and other solid particles in the flue gas before the gas is passed through a dust separator is in the order of 1 g per normal cubic meter of the gas while in the system of the invention the corresponding figure was only 50 mg. No smoke could be seen from the chimney. The low content of dust and other solid particles is due to the fact that the high particle velocity across the fuel bed brings about a substantially complete combustion of the black coal such that the flue gas contained no unburnt coal particles. Normally, there is a relationship between the content of dust and other solid particles and the concentration of carbon monoxide in the flue gas. This is due to the fact that dust and other solid particles as well as carbon monoxide is generated when the combustion is incomplete. It was found in the test described above that the concentration of carbon monoxide was very low, which further confirms the beneficial effect of treatment by sound. The test also showed that the content of nitrogen oxides in the flue gas was very low, which is another advantage achieved by a low frequency sound.

The invention relates to method and apparatus for the combustion of large solid fuels. In order to improve the beneficial effect of sound on combustion are a bed of the fuel located on a grate, the bed of fuel is exposed to a high particle velocity of a sound positively produced by an external low frequency sound generator, the frequency of which is determined by the sound generator, to provide a reciprocating movement of combustion air and combustion gas through the fuel bed. The dimensions of the grate in a plane transverse to the reciprocating movement of combustion air and combustion gas are less than a quarter of the wave length of the sound generated by the sound generator.

FIELD OF THE INVENTION The present invention relates to pneumatic tires, and more particularly to pneumatic radial tires which can improve ride feeling by using a rubber composition which has a high flex resistance and produces an excellent damping effect in the sidewalls. BACKGROUND OF THE INVENTION Recently, resource and energy savings have been socially demanded. As a result, the development of so-called low fuel consumption tires has been eagerly carried out to reduce power loss. For this purpose, not only have tire structures been modified and the weight of tires been reduced, but also, almost all of the rubber compositions in all of the parts of the tire have been replaced with those yielding a lower energy loss. However, utilization of lower energy loss rubber compositions in all of the parts of the tire has resulted in very poor ride feeling of the tire. Based upon consideration of the above-mentioned result and on the highly-advanced technology of lower energy consumption, it has been proposed to prepare a rubber composition having high energy loss in the sidewalls which will bring about an improvement in ride feeling. Such a composition having high energy loss can be prepared, for example, by (1) an increased addition of regular carbon black, (2) use of higher-quality carbon black or (3) an increased addition of softener. However, each of these approaches has unavoidable drawbacks. An increased addition of regular carbon black means an increase in the modulus of elasticity of the rubber composition. Not only is it impossible by this means to improve the ride feeling but it also unfavorably lowers the flex resistance. The use of higher-quality carbon black increases the storage modulus of elasticity E' of the rubber composition and this is not desirable from the standpoint of cut growth which starts from a small incision on the sidewall. An increased addition of softener greatly lowers the weather resistance of the composition. SUMMARY OF THE INVENTION A principal object of this invention is to provide a pneumatic radial tire which can improve the ride feeling by using an improved rubber composition possessing high energy loss in the sidewalls. More particularly, this invention relates to a pneumatic radial tire having sidewalls, the vulcanizable rubber composition of which comprises, based on 100 parts by weight of rubber, 20 to 90 parts by weight of butadiene-piperylene copolymer and 80 to 10 parts by weight of at least one rubbery diene polymer selected from the group consisting of natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, butadiene-styrene copolymer rubber, ethylene-propylene-diene ternary copolymer rubber and acrylonitrile-butadiene copolymer rubber. The vulcanizable rubber composition comprises 20 to 120 parts by weight of carbon black in the same manner as a usual rubber composition. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows sidewall A of a tire and FIG. 2 shows portion C in the sidewall which is particularly suitable for the arrangement of the rubber composition according to the present invention. Portion C extends, as shown in FIG. 2, from the position of maximum tire width W in sidewall A to bead B. DETAILED DESCRIPTION OF THE INVENTION The butadiene-piperylene copolymers according to the present invention can be prepared by known methods (see U.S. Pat. No. 3,972,862, Canadian Pat. No. 1,042,141). The average molecular weight of the copolymers varies between about 150,000 and 500,000. The amount of the butadiene-piperylene copolymer is limited to 20 to 90 parts by weight based on 100 parts by weight of rubber in the rubber composition according to the present invention because the sidewall in the tire of this invention cannot improve the damping effect when the amount is less than 20 parts by weight and, because sidewall cut resistance is lost when the amount is more than 90 parts by weight. The butadiene-piperylene copolymer is selected because polybutadiene rubber has excellent flex resistance but low tensile strength. In order to improve the tensile strength, the microstructure of polybutadiene is changed from the cis to the trans form. Further, the possibility of crystallization of polybutadiene is prevented by disturbing the regularity of trans polybutadiene by copolymerization with 1,3-pentadiene so as to prevent any rapid change in the modulus of elasticity in the piperylene which arises as a result of melting the crystals when the tire is in operation. 1,3-pentadiene is particularly useful because it is a monomer which can be easily obtained commercially in the form of the C5 fraction from crude oil and because its polymer has such a structure as to comprise methyl groups which do not directly bond to the carbon atoms of the double bonds. Hence, 1,3-pentadiene never lowers the flex resistance of the composition. It is preferable that the butadiene-piperylene copolymer has a 1,3-pentadiene content between 15 to 50% by weight of the copolymer because it is impossible to sufficiently prevent the crystallization of trans-1,4-polybutadiene when the content of 1,3-pentadiene is less than 15% by weight. When crystallization is not prevented, the tire modulus of elasticity rapidly changes due to the melting of the crystal within the usual temperature range of tire operation (10° to 100° C.). This is not desirable because it becomes impossible to expect what the excellent flex resistance of polybutadiene is when the content of 1,3-pentadiene is more than 50% by weight. The amount of carbon black to be used is preferably limited to 20 to 120 parts by weight because the modulus of elasticity and the tensile strength are not sufficient when the amount is less than 20 parts by weight and because the production operability for making the sidewalls is low and the flex resistance is greatly reduced when the amount exceeds 120 parts by weight. The rebound resilience, measured at 30° C. with a Dunlop tripsometer, of the sidewall according to the present invention is preferably limited to not more than 50% because it is impossible to sufficiently improve the ride feeling when the resilience is higher than 50%. The pneumatic radial tire of the present invention can improve the ride feeling when the vulcanizable rubber composition is arranged, as shown in FIG. 1, on sidewall A. The upper portion from the position of the maximum tire width W can greatly add to the rolling resistance of the tire, whereas the lower portion from the position of the maximum tire width W, i.e., the portion extending between the bead B and the position of maximum tire width W, can greatly add to the ride feeling performance. Thus, it is more desirable to provide a radial tire for low fuel consumption and excellent ride feeling by arranging the vulcanizable rubber composition according to the present invention all along part C, as shown in FIG. 2, extending from bead B to the position of maximum tire width W. Since the vulcanizable rubber composition according to the present invention has (1) a markedly lower modulus of elasticity than that of any other similar composition of diene homopolymers and copolymers, (2) a flex resistance which is equal to or higher than that of cis-polybutadiene rubber even if the content of carbon black is increased, (3) a high tensile strength and (4) a high energy loss, it is highly suitable for obtaining a pneumatic radial tire with improved ride feeling performance. The following non-limiting examples describe the invention in more detail. EXAMPLES 1 TO 4 The butadiene-piperylene copolymer was prepared as follows: In a 5 l flask equipped with a stirrer, a dropping funnel and a side cock (all of which were connected through ground connecting conical pipes), 1.3 l anhydrous toluene, 5 ml Al(C 2 H 5 ) 2 Cl, 1.365 g CCl 3 COOH, 300 g 1,3-butadiene and 50 ml piperylene were added to prepare a solution. The composition of piperylene used was as follows: trans-1,3-Pentadiene--62.6% cis-1,3-Pentadiene--27.5% Cyclopentene--8.66% Cyclopentadiene--0.68% Other C 5 isomers--0.56% This solution was cooled to 3° C. and another solution containing 60 mg vanadium triacetyl acetonate in 10 ml of toluene was added to the former solution. The polymerization was activated by the further addition of 70 ml of piperylene. After three hours, the polymerization was stopped, the reaction product was coagulated by alcohol and then dried through a hot roll. The product was analyzed using an infrared absorption spectrometer. The analysis showed that the copolymerized pentadiene unit corresponded to 35% of the total polymer weight and its viscosity η was 233 dl/g in toluene at 30° C. The butadiene-piperylene colpolymer thus obtained, hereinafter referred to as "sample", was mixed with natural rubber, carbon black, etc., in the proportions as shown in Table 1 below. The characteristics of each of the compositions are also shown in Table 1 below. Note, the values in Tables 1, 3 and 4 are in parts by weight unless otherwise indicated. TABLE 1__________________________________________________________________________ Comparative Example Example Example Comparative Example Example 1 1 2 3 Example 2 4__________________________________________________________________________Natural rubber 85 80 50 10 5 35Sample 15 20 50 90 95 50SBR 1500.sup.1 -- -- -- -- -- 15HAF.sup.2 45 45 45 45 45 45Aromatic oil 10 10 10 10 10 10Antioxidant IPPD.sup.3 2 2 2 2 2 2Stearic acid 2 2 2 2 2 2ZnO 3 3 3 3 3 3Accelerator MBTS.sup.4 -- -- 0.2 0.2 0.2 0.2Accelerator OBS.sup.5 0.7 0.7 0.6 0.7 0.7 0.7Sulfur 1.5 1.5 1.5 1.5 1.5 1.5100% modulus at 30° C. in kg/cm.sup.2 16 16 14 13 13 14Rebound resilience at 30° C. 50.3 48.6 47.3 41.2 40.6 45.8Flex resistance 95 123 246 314 303 168Ride feeling 3 4 5 5 5 5Cut resistance 120 118 100 88 80 112__________________________________________________________________________ Note: .sup. 1 SBR 1500 = Styrenebutadiene rubber 1500 .sup. 2 HAF = Phil Black N 330 .sup. 3 Antioxidant IPPD: Ozonone 3C manufactured by Seiko Kagaku Corp., corresponding to N--phenylN'--isopropyl-p-phenylenediamine. .sup. 4 Accelerator MBTS: Nocceler DM manufactured by Ouchi Shinko Kagaku Industries, corresponding to dibenzothiazyldisulfide. .sup. 5 Accelerator OBS: Nocceler MSA manufactured by Ouchi Shinko Kagaku corresponding to N--oxydiethylene2-benzothiazolesulfenamide. Flex resistance was estimated from the following formula by determining the time elapsed until the initial crack appeared after flexing each sample without an initial incision, according to the flexing test, JIS K 6301: ##EQU1## Ride feeling was estimated as follows: A vehicle with four test tires (size: 175 SR 14) was driven at the speed of 60 km/h over ten 10 mm diameter pipes arranged at regular intervals of 10 m. The noise and the vibrations produced by driving over the pipes were estimated and classified into five grades and averages. The larger the value the better the ride feeling. Cut resistance was estimated as follows: An edge having an angle of 45° was shot at 8 cm thick vulcanized rubber composition blocks at a speed of 0.894 m/sec and an energy of 120 joules. The depth of the incision produced by the collision was then measured. An index of the cut resistance was calculated from the results according to the following formula: ##EQU2## Index 100 corresponds to 38.5 mm which is equal to the depth of the incision in Example 2. The larger the index the better the cut resistance of the tire. The smallest index applicable to the tire sidewalls is 85. The test data in Table 1 shows that the amount of the conjugated diolefin copolymer in the present invention is limited to 20 to 90 parts by weight. EXAMPLES 5 TO 7 In a 5 l flask, equipped with a stirrer, a dropping funnel and a side cock (all of which were connected through ground connecting conical pipes), the following compounds were added as raw materials to prepare several solutions. TABLE 2(a)______________________________________ A B C D E______________________________________Anhydrous toluene (l) 1.3 1.3 1.3 1.3 1.3Al(C.sub.2 H.sub.5).sub.2 Cl (ml) 5 5 5 5 5CCl.sub.3 COOH (g) 1.365 1.365 1.365 1.365 1.3651,3-Butadiene (g) 300 300 300 300 300Piperylene (ml) 50 50 50 80 100______________________________________ Composition of piperylene used: trans-1,3-Pentadiene--62.6% cis-1,3-Pentadiene--27.5% Cyclopentene--8.66% Cyclopentadiene--0.68% Other C 5 isomers--0.56% Solutions A to E were cooled to 3° C. and another solution containing 60 mg vanadium triacetyl acetonate in 10 ml of toluene was added to the former solution. 0, 15, 70, 90 and 100 ml of piperylene was further added to these solutions, respectively. After three hours, each polymerization was stopped, the reaction product was coagulated by alcohol and then dried through a hot roll. Each product was analyzed using an infrared absorption spectrometer. The analysis showed that the copolymerized pentadiene unit corresponded to the percentage of the total polymer weight and its viscosity value, as is shown in Table 2(b). TABLE 2(b)______________________________________ A B C D E______________________________________Content in % by weight 13 18 33 46 55Viscosity [η] in 1.83 2.01 2.33 1.68 2.51toluene at 30° C.______________________________________ The flex resistance values of the rubber compositions obtained by using these polymers are shown in Table 3. TABLE 3__________________________________________________________________________ Comparative Example Example Example Comparative Comparative Example 3 5 6 7 Example 4 Example 5__________________________________________________________________________CopolymerSample A 50 -- -- -- -- --Sample B -- 50 -- -- -- --Sample C -- -- 50 -- -- --Sample D -- -- -- 50 -- --Sample E -- -- -- -- 50 --Polybutadiene (BR 01) -- -- -- -- -- 50Natural rubber 50 50 50 50 50 50Carbon black HAF 50 50 50 50 50 50Aromatic oil 10 10 10 10 10 10Antioxidant IPPD 2.0 2.0 2.0 2.0 2.0 2.0Stearic acid 2.0 2.0 2.0 2.0 2.0 2.0ZnO 3.0 3.0 3.0 3.0 3.0 3.0Accelerator MBTS 0.2 0.2 0.2 0.2 0.2 0.2Accelerator OBS 0.6 0.6 0.6 0.6 0.6 0.6Sulfur 1.5 1.5 1.5 1.5 1.5 1.5Flex resistance 86 151 243 186 93 100__________________________________________________________________________ The data in Table 3 suggests that a preferable relative amount of 1,3-pentadiene contained in the butadiene-piperylene copolymers is 15 to 50% by weight. EXAMPLES 8 AND 9 The data in Table 4 below shows that with the same flex resistance of the rubber compositions of the present invention (Examples 8 and 9) there is a larger energy loss than when other conventional rubber compositions are employed for sidewalls. TABLE 4__________________________________________________________________________ Example Example Comparative Comparative Comparative Comparative Comparative 8 9 Example 6 Example 7 Example 8 Example 9 Example__________________________________________________________________________ 10Natural rubber 50 50 50 50 50 50 50Polybutadiene (BR 01) -- -- 50 50 50 50 50Sample C 50 50 -- -- -- -- --Carbon black FEF 50 55 40 45 50 55 45Aromatic oil 8 8 8 8 8 8 15Antioxidant IPPD 2.0 2.0 2.0 2.0 2.0 2.0 2.0Stearic acid 2.0 2.0 2.0 2.0 2.0 2.0 2.0ZnO 3.0 3.0 3.0 3.0 3.0 3.0 3.0Accelerator MBTS 0.2 0.2 0.2 0.2 0.2 0.2 0.2Accelerator OBS 0.6 0.6 0.6 0.6 0.6 0.6 0.6Sulfur 1.5 1.5 1.5 1.5 1.5 1.5 1.5100% modulus at 30° C. 14 14.5 14 17 20 23.5 14.5in kg/cm.sup.2Flex resistance 253 221 185 136 108 71 119Weather resistance B-1 B-1 C-2 B-2 B-1 B-1 C-4(Ozone cracking test)Rebound resilience 47.6 45.2 56.5 53.2 50.6 48.2 49.8at 30° C.Ride feeling 5 5 3 2 1 2 4__________________________________________________________________________ Weather resistance was measured with a weathering test apparatus, Model OMS-R-2, manufactured by Suga Shikenki K.K., according to JIS K 6301. Measuring conditions: Duration--48 hr Elongation--30% strain Temperature--40° C. Ozone concentration--50 pphm The state of the weather resistance was recorded on the basis of the characteristics shown in Table 5. TABLE 5 Number of cracks A: Small in number B: Large in number C: Innumerable in number Size and Depth of cracks 1: Invisible to the naked eye but visible when using a 10X magnifying glass 2: Visible to the naked eye 3: Cracks are deep and relatively large (less than 1 mm) 4: Cracks are deep and large (from 1 mm to less than 3 mm) 5: Cracks are 3 mm or more EXAMPLES 10 AND 11 In these examples, the rubber composition according to the present invention was applied to tire sidewalls to observe its effects. In Example 10, the rubber composition according to Example 7 was applied to tire sidewall A as shown in FIG. 1 to prepare a 175 SR 14 tire. In Example 11, the rubber composition according to Example 7 was applied to portion C between the position of maximum tire width and bead B, and according to Comparative Example 6 was applied to portion D above portion C to prepare a 175 SR 14 tire. The results obtained are shown in Table 6 below. TABLE 6______________________________________ Example 10 Example 11______________________________________Portion C Composition of Composition of Example 7 Example 7Portion D Composition of Composition of Example 7 Comparative Example 6Rolling 100 104.5resistance (control)Ride feeling 5 5______________________________________ Rolling resistance was measured under the following conditions: The test tire, subjected to an internal pressure of 1.7 kg/cm 2 , was trained on a steel drum with a diameter of 1,707.6 mm and a width of 350 mm that was rotated by driving a motor at a speed of 80 km/hr under a JIS 100% load (385 kg) for 30 minutes. Thereafter, the rotating speed of the drum was raised to 100 km/hr. Then, the driving of the motor was stopped and the drum was allowed to run by inertia during which the rolling resistance of the tire to the drum at a speed of 50 km/hr was measured on a basis of the deceleration speed of the drum and the time change. Next, the net rolling resistance of the tire was determined by subtracting the previously calculated drum resistance from the measured value. Moreover, the rolling resistance of the test tire was evaluated by the following formula: ##EQU3## wherein the rolling resistance of Example 10 was utilized as a control. It can be seen from the results in Table 1, Table 4 and Table 6 that the pneumatic radial tire of the present invention yields an excellent ride feeling without lowering the flex resistance, cut resistance or weather resistance. While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.

A pneumatic radial tire having sidewalls, the rubber composition of said sidewalls comprising, based on 100 parts by weight of rubber, 20 to 90 parts by weight of butadienepiperylene copolymer and 80 to 10 parts by weight of at least one rubbery diene polymer selected from the group consisting of natural rubber, synthetic polyisoprene rubber, polybutadiene rubber, butadiene-styrene copolymer rubber, ethylenepropylene-diene ternary copolymer rubber and acrylonitrile-butadiene copolymer rubber.

BACKGROUND [0001] This invention relates to threaded fasteners. More particularly, this invention relates to a device for and method of lubricating threaded fasteners and other threaded connections. [0002] Bolts are roughly cylindrical connector elements having external threads whereas nuts are annular in shape and have internal threads that mate with the external threads of the bolt. For purposes of this disclosure, “bolt” will refer generally to any connection having external threads while “nut” will refer generally to any connection element having internal mating threads. When a bolt is passed through a medium and a nut is tightened over the bolt, it places the bolt in tension and the medium in compression. The medium can comprise any material to be fastened by the nut and bolt combination, such as engine parts, structural elements, pressure vessel flanges etc. In many instances, the amount of tension required in the bolt is predetermined and necessary to obtain a certain amount of compression in the medium. [0003] Previous methods of tensioning include measuring the torque applied to the nut and estimating from that measurement the amount of tension on the bolt. This method, however suffers from the drawback that friction between the threads of the nut and the bolt may vary from one nut/bolt combination to next and is affected by a number of factors including coatings, corrosion, heat, dust, moisture, and manufacturing differences or imperfections. [0004] Another method for accurately tensioning a bolt includes the use of a direct tension indicator, such as are discussed in commonly-assigned U.S. Pat. No. 5,769,581, issued Jun. 23, 1998, U.S. Pat. No. 5,931,618 issued Aug. 2, 1999, and U.S. Pat. No. 6,152,665 issued Nov. 28, 2000, all of which are issued to Wallace et al. and are wholly incorporated herein by reference. Reference is also made to U.S. patent application Ser. No. 09/613,993 filed Jul. 11, 2000 by W John A. Herr et al., said application also being incorporated herein by reference. In such devices, a washer-like element having protrusions is placed between the nut and the bolt head. The protrusions are calibrated to deform and flatten when the desired amount of bolt tension is reached. The amount of tension can then be determined based on the gap between adjacent elements caused by the direct tension indicator. [0005] Direct tension indicators are currently available in the “regular” and “selfindicating” types. The regular style requires the use of a feeler gauge to judge the residual gap closure. The self-indicating style include an elastomeric dye that becomes ejected from beneath the protrusions when the protrusions are flattened. Thus, with the self indicating style, the residual gap closure is judged by a visual assessment of the “squirt event.” [0006] Both styles of direct tension indicators are used on bolts to control the tension of the bolt as it is being tightened. [0007] It has been found, however, that friction between the threads of the nut and bolt can adversely affect the performance of these devices as well. Specifically, friction can undermine confidence in direct tensioning devices when the necessary effort to reach the specified bolt tension is much greater than expected due to the friction. Thus, when the torque resistance within the bolt assembly builds up to the point where the bolt tightening equipment cannot overcome it, the direct tension indicator protrusions are unacceptably high, and it may be declared that the bolt has not been tensioned correctly. Because of excessive torque buildup, therefore, the bolt tightening equipment is inadequate. The bolt installers often incorrectly attribute this failure to correctly compress the direct tension indicator protrusions to the direct tension indicator having been manufactured with protrusions that are too strong. This incorrect conclusion results in improper bolt tightening and controversial corrective procedures and extra cost. [0008] It would therefore be desirable to provide a means for controlling the friction between the threads of the bolt and the threads of the nut to reduce the effort required to overcome friction effects and therefore improve user confidence in the direct tension indicators. SUMMARY [0009] The above and other disadvantages of the prior art are overcome or alleviated by a friction reducing device comprising a stretchable thin film of elastomeric material impregnated or dusted with lubricating material. The thin film adheres to an annular member through which a fastener element having external threads can pass. [0010] The above described and other features are exemplified by the following figures and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS [0011] [0011]FIG. 1 shows an exploded view of a bolt assembly according to one embodiment. [0012] [0012]FIG. 2 shows the assembly of FIG. 1 as it appears when assembled. [0013] [0013]FIG. 3 shows an exploded view of a bolt assembly according to another embodiment. [0014] [0014]FIG. 4 shows an exploded view of a bolt assembly according to yet another embodiment. [0015] [0015]FIG. 4 a shows a cross-sectional view of a nut assembly according to yet another embodiment. [0016] [0016]FIG. 5 is a graph of torque versus tension for a direct tension indicating washer with and without a lubricating membrane. DETAILED DESCRIPTION [0017] [0017]FIG. 1 shows an exploded view of a bolt assembly according to a first embodiment in which a bolt 12 extends through medium 15 , direct tension indicator 20 , washer 30 , and nut 14 for fastening and applying compressive force to medium 15 . Bolt 12 , washer 30 , and nut 14 are of conventional manufacture and individually do not form a part of the invention. Direct tension indicator 20 is constructed in accordance with previous direct tension indicators as discussed in the background section above, with the exception of the addition of a lubricating membrane 22 , which is disposed at an underside 24 and/or an inner diameter 26 of the direct tension indicator 20 . [0018] Lubricating membrane 22 is a stretchable thin film optionally impregnated with lubricant. The thin film is an elastomeric material, i.e., a material that is able to undergo large, reversible deformations. Useful elastomeric materials include, without limitation, natural and synthetic elastomers. For example, these elastomers include, without limitation, natural rubber, synthetic polyisoprene rubber, styrene/butadiene rubber (SBR), polybutadiene, butyl rubber, neoprene, ethylene/propylene rubber, ethylene/propylene/diene rubber (EPDM), acrylonitrile/butadiene rubber (NBR), silicone rubber, the fluoroelastomers, ethylene acrylic rubber, ethylene vinyl acetate copolymers (EVA) epichlorohydrin rubbers, chlorinated polyethylene rubber, chlorosulfonated polyethylene rubbers, hydrogenated nitrile rubber, tetrafluoroethylene/propylene rubber, polyamides, including polyether block amides, polyurethane and mixtures thereof. As used herein, the term elastomer will refer to a blend of synthetic and natural rubber, a blend of various synthetic elastomers, or simply one type of elastomer as well as functionalized elastomers and the like. Preferred elastomers are polyurethanes, including those available from E. I. Du Pont de Nemours Co., under the trade name LYCRA® polyurethane. [0019] Examples of the optional lubricant that can be incorporated into the thin film include graphite, fluorinated graphite, hexagonal boron nitride, molybdenum disulfide, antimony sulfide, mica, fluorine mica, talc, tungsten disulfide, carbon black, polymers such as tetrafluoroethylene (i.e., Teflon), mixtures thereof, and the like. [0020] The film is applied by dispensing the elastomer within the inner diameter of the direct tension indicator 20 , heat curing, and treating with a mold release agent to free the film from the containing surface. A thread lubricant is then dusted, coated or otherwise applied to the film. Examples of the thread lubricant include graphite, fluorinated graphite, hexagonal boron nitride, molybdenum disulfide, antimony sulfide, mica, fluorine mica, talc, tungsten disulfide, carbon black, polymers such as tetrafluoroethylene (i.e., Teflon), mixtures thereof, and the like. Alternatively, the elastomer can be attached over a bottom surface of the direct tension indicator as a stretched film that clings to the direct tension indicator surface and outer edge. Such a film would not need curing, but would still be dusted with a thread lubricant. [0021] When the direct tension indicator is installed over the bolt threads as shown in FIG. 2, the lubricating film stretches and forms a lubricating prophylactic membrane that reduces the frictional resistance within the mating threads and ahead of the nut, and therefore reduces the torque build-up. [0022] Referring to FIG. 5, the benefits of the lubricating membrane is graphed with the torque applied to the nut being plotted on the y-axis and the resulting bolt tension being plotted on the x-axis. Tension is also indicated by the protrusion height which is depicted beneath the x-axis. To obtain the desired tension A, a torque τ 1 must be obtained when the bolt and/or nut is weathered or otherwise not in ideal condition. However, the maximum amount of torque available to install the bolt is B, which is less than τ 1 , therefore desired amount of tension is not obtained and the protrusions remain unflattened, thereby rejecting the amount of applied tension. [0023] With the lubricating membrane, however, the necessary torque to obtain the desired tension A is τ 2 , which is less than τ 1 as well as the maximum torque available B. Thus, the nut is tightened until the direct tension indicator protrusion flattens as required whereupon the bolt tension amount is A. [0024] Thus, the action of installing direct tension indicator 20 having lubricating membrane 22 , accomplishes the automatic lubrication of the bolt assembly. The benefits of easier bolt installation and easier direct tension indicator compression leads to a more accurate bolt tension result without any extra work. [0025] [0025]FIG. 3 shows a second embodiment in which lubricating membrane 22 is installed on washer 30 rather than direct tension indicator 20 . This achieves a similar benefit to the embodiments shown in FIGS. 1 and 2 described above, but provide more flexible use of the lubricating membrane and indicator. FIG. 4 shows another embodiment wherein a lubricating membrane 22 is attached to washer 33 for reducing the amount and provide a more predictable friction amount between nut 14 and bolt 12 . FIG. 4 a shows another embodiment where the lubricating membrane 22 is attached to nut 14 . This not only reduces the effort required to tighten the bolt assembly, but improves the tensioning accuracy of a torque wrench. [0026] While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.

A friction reducing device comprises a stretchable thin film of elastomeric material impregnated or dusted with lubricating material. The thin film adheres to an annular member through which a fastener element having external threads can pass.

REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Application 61/101,137 that was filed on Sep. 29, 2008. FIELD OF THE INVENTION The present invention generally relates to sensors and methods for measuring the moisture content in paper products and particularly to techniques for measuring the levels of gypsum, which contains crystal water, in order to determine the amount of “free” water that is present in the paper products especially paper products that also contain calcium carbonate. BACKGROUND OF THE INVENTION In the manufacture of paper on continuous papermaking machines, a web of paper is formed from an aqueous suspension of fibers (stock) on a traveling mesh papermaking fabric and water drains by gravity and suction through the fabric. The web is then transferred to the pressing section where more water is removed by pressure and vacuum. The web next enters the dryer section where steam heated dryers and hot air completes the drying process. The paper machine is, in essence, a water removal, system. A typical forming section of a papermaking machine includes an endless traveling papermaking fabric or wire, which travels over a series of water removal elements such as table rolls, foils, vacuum foils, and suction boxes. The stock is carried on the top surface of the papermaking fabric and is de-watered as the stock travels over the successive de-watering elements to form a sheet of paper. Finally, the wet sheet is transferred to the press section of the papermaking machine where enough water is removed to form a sheet of paper. Paper is generally made of three constituents: water, wood pulp fiber, and ash. “Ash” is defined as that portion of the paper which remains after complete combustion. In particular, ash may include various mineral components such as calcium carbonate (CaCO 3 ), titanium dioxide (TiO 2 ), and clay (a major component of clay is SiO 2 ). Paper manufacturers use fillers such clay, titanium dioxide and calcium carbonate to enhance printability, color and other physical characteristics of the paper. Because of its low cost, paper manufacturers are also adding gypsum (CaSO 4 2H 2 O) as filler, especially in combination with calcium carbonate. The dihydrated water is commonly referred to as “crystal” water. Gypsum loses its associated water molecules when it heated to a temperature of about 200° C. It is conventional to measure the moisture content of sheet material upon its leaving the main dryer section or at the take up reel employing scanning sensors. Such measurements may be used to adjust the machine operation toward achieving desired parameters. One technique for measuring moisture content is to utilize the absorption spectrum of water in the infrared (IR) region. A monitoring or gauge apparatus for this purpose is commonly employed. Such an apparatus conventionally uses either a fixed gauge or a gauge mounted on a scanning head which is repetitively scanned transversely across the web at the exit from the dryer section and/or upon entry to the take up reel, as required by the individual machines. IR moisture measuring devices do not distinguish “free” water that is present in paper products from “crystal” water, in other words, IR moisture measurements yield a moisture content that is the sum of the free water and crystal water. It is desirable to obtain on-line measurements of the free water content. The total amount of ash in paper and the composition of the ash are controlled by setting the rates of flow of gypsum and other ash components as well as the flow of wood pulp fiber and water to the papermaking system. The resulting sheet is periodically sampled and burned in the laboratory to determine the composition and amount of ash in the sheet. In the laboratory, the paper is burned under predetermined conditions and the resulting ash is accurately weighed and chemically analyzed. The papermaking parameters can then be altered based upon the resulting measurements. However, this procedure of manual control suffers from the main disadvantage that it is time consuming, even when the gypsum is the only ash component used. Thus, large quantities of paper which do not meet specifications may be manufactured while the laboratory tests are being conducted. The art is in search of improved on-line moisture sensing techniques for measuring the free water content of paper products that include gypsum. SUMMARY OF THE INVENTION The present invention is directed to techniques for correcting for gypsum crystal water effect, on infrared moisture measurements, that can be obtained directly from analysis of X-ray absorption spectra of paper products that contain both calcium carbonate and gypsum (CaSO 4 2H 2 O). The invention is based in part on the discovery of a unique X-ray spectrum that enables the measurement and determination of the amount of gypsum that is present even in the presence of calcium carbonate. In particular, it has been demonstrated that an X-ray system that employs dual X-ray sensors operating at different known X-ray spectra, one spectra being sensitive to the total ash quantity that is present in the paper product and the second spectra being primarily sensitive to gypsum, yields accurate calculations of the amount of gypsum that is present. The level of crystal water can be readily derived from the gypsum content. In one aspect, the invention is directed to dual X-ray sensors that include (i) a first X-ray source for directing first X-rays through a first portion of the paper product wherein the first X-rays source is powered by a first voltage power supply that powers the first X-ray source at a voltage of about 5.9 KV and corresponding means for detecting first X-rays that are transmitted through the first position on the paper product and generating a first signals indicative of the amount of first X-rays detected and (ii) a second X-ray source for directing second X-rays through a second portion of the paper product wherein the second X-rays source is powered by a second voltage power supply that powers the second X-ray source at a voltage of about 4.2 KV and corresponding means for detecting second X-rays that are transmitted through the second portion of the paper product and generating second signals indicative of the amount of second X-rays detected. The dual X-ray sensor system can be employed to compute the amount of crystal (non-free) moisture in paper which contains both gypsum and calcium carbonate. In particular, in the manufacture of paper, the on-line infrared total moisture measurements of the paper products are corrected for the gypsum crystal water effect to yield free moisture measurements. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a system that employs dual X-ray gauges (sensors) for on-line gypsum measurements; FIG. 2 is a graph of calculated X-ray absorption curves showing the absorption coefficients for pure calcium carbonate and for gypsum vs. applied voltage to X-ray tube; and FIG. 3 illustrates a sheetmaking system incorporating the dual X-ray gauges of the present invention. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The present invention is directed to a non-contact, on-line sensor system for measuring the free moisture content of paper products that contain gypsum. The sensor system is particularly suited for incorporation into industrial paper making machines. FIG. 1 illustrates a sensor system for measuring the free water content in paper sheet 10 which contains gypsum. The system includes dual X-ray absorption measurement devices that operate at different wavelengths: (1) ash X-ray sensor includes X-ray tube 24 , that is powered by a fixed high voltage power supply 28 , and a corresponding X-ray detector 12 , and (2) the gypsum X-ray sensor includes X-ray tube 26 , that is powered by a fixed high voltage power supply 30 , and a corresponding X-ray detector 14 . A radiation shield 40 partially encloses the dual X-ray sensors. The system preferably includes a scanner device 18 that moves the sensors across sheet 10 with the X-ray tubes 24 and 26 positioned on one side of sheet 10 and the corresponding X-ray detectors (or receivers) 12 and 14 positioned on the opposite side. The space between the X-ray tubes and detectors defines a measurement gap. The fixed high voltage power supplies 28 and 30 are used to generate X-rays at selected energies. The fixed high voltage supply powers total ash X-ray tube 24 at a voltage so that X-rays generated are sensitive to both gypsum and calcium carbonate. Preferably this voltage is maintained at about 5.9 KV. For the gypsum X-ray sensor, the Fixed high voltage supply powers X-ray tube 26 at a voltage so that the X-rays generated are sensitive to primarily gypsum. Preferably, this voltage is maintained at about 4.3 KV. X-ray filters 12 and 14 , in the form of aluminum plate, for example, can be employed to enhance the composition analysis. In operation, X-rays from X-ray tubes 20 and 22 that are transmitted through sheet 10 are received by X-ray detectors 12 and 14 , respectively. Simultaneously, detector 12 generates analog signals that are transmitted through amplifier 32 and analog-to-digital converter 36 to computer processor 16 . Similarly, detector 14 generates analog signals that are transmitted through amplifier 34 and analog-to-digital converter 38 to processor 16 . The effective absorption coefficient for calcium carbonate (curve 1 ) and gypsum (curve 2 ) were measured at a spectral region of about 4.2 to 6.2 KV and the results are shown in FIG. 2 . An X-ray gauge consisting of a conventional X-ray tube and corresponding detector with no aluminum filter was used. As is apparent, there is a cross over point at about 5.9 KV and there is almost a factor 2 difference in absorption region below about 4.2 KV. Thus, in a preferred embodiment, the first (or ash) X-ray sensor operates at 5.9 KV and the second (or gypsum) X-ray sensor operates at 4.2 KV. Processor 16 correlates the weighted sum of transmittance measurements to the amount of gypsum wherein the sum-coefficients are given by a fit to laboratory data. Specifically, processor 16 initially calculates the relative readings for each X-ray sensor, which is defined by the relationship: R=V/Vo, where V is the measured detector response when the sheet is in place and Vo is the measured detector response with no sheet in the measurement gap. This sensor ratio R is then employed to calculate the gypsum fraction using the following relationship: CaSO 4 2H 2 O %= a Ln(R h )/BW n +b Ln(R l )/BW n +c where BWn is the total mass of the sheet and R h , R l are the ratios for X-ray sensor set to the higher (h) and the lower (l) voltage and (a, b, c) are constants to be determined by comparing to chemical laboratory data. The dual X-ray sensor is particularly suited for use in a papermaking machine such as that illustrated in FIG. 3 . The sheetmaking system for producing a continuous sheet of paper material 44 includes a headbox 62 , a steambox 58 , a calendaring stack 60 , a take-up reel 76 and scanner system 70 that includes the inventive dual X-ray sensors. In the headbox 62 , actuators are arranged to control discharge of wetstock onto supporting wire or web 66 along the cross direction. The sheet of fibrous material that forms on top of the wire 66 is trained to travel in the machine direction between rollers 64 and 68 and passes through a calendaring stack 60 . The calendaring stack 60 includes actuators that control the compressive pressure applied across the paper web. The sheetmaking system includes a press section (not shown) where water is mechanically removed from the sheet and where the web is consolidated. Thereafter, water is removed by evaporation in the dryer section (not shown). The finished sheet product 74 is collected on a reel 76 . In practice, the portion of the paper making process near a headbox is referred to as the “wet end”, while the portion of the process near a take-up reel is referred to as the “dry end”. The scanner system 70 generally includes pairs of horizontally extending guide tracks 54 that span the width of the paper product 74 . The guide tracks are supported at their opposite ends by upstanding stanchions 52 and are spaced apart vertically by a distance sufficient to allow clearance for paper product 74 to travel between the tracks. The dual X-ray sensors are secured to a carriage 56 that moves back-and-forth over to paper product 74 as measurements are made. On-line scanning sensor systems for papermaking manufacture are disclosed in U.S. Pat. No. 4,879,471 to Dahlquist, U.S. Pat. No. 5,094,535 to Dahlquist et al., and U.S. Pat. No. 5,166,748 to Dahlquist, all of which are incorporated herein fully by reference. The dual X-ray sensors can be employed to adjust water measurements to account for the presence of gypsum crystal water in order to determine the free water content of paper products. On-line moisture measurements are typically obtained by infrared detectors that are positioned at various locations in the papermaking process in the machine direction and/or cross direction. For example, moisture detector 50 ( FIG. 1 ) can also be secured to carriage 56 of the scanner system 70 ( FIG. 3 .). Suitable moisture detection devices are described, for example, U.S. Pat. No. 7,382,456 to Tixier et al., U.S. Pat. No. 7,321,425 to Haran, and U.S. Pat. No. 7,291,856. to Haran et al., which are incorporated herein by reference. Once the free water content is calculated, operating parameters of the papermaking machine can be adjusted, if necessary, should the water profile deviate from normal. Suitable control process is described in U.S. Pat. No. 6,092,003 to Hagart-Alexander which is incorporated herein by reference. Both dry end parameters, e.g., temperature of heating devices, and wet end parameters, e.g., wet stock water content and filler content, can be controlled to achieve the desired final product. Process control techniques for papermaking machines are further described, for instance, in U.S. Pat. No. 6,805,899 to MacHattie et al., U.S. Pat. No. 6,466,839 to Heaven et al., U.S. Pat. No. 6,149,770, to Hu et al., U.S. Pat. No. 6,092,003 to Hagart-Alexander et. al, U.S. Pat. No. 6,080,278 to Heaven et al., U.S. Pat. No. 6,059,931 to Hu et al. U.S. Pat. No. 5,853,543 to Hu et al., and U.S. Pat. No. 5,892,679 to He, which are all incorporated herein by reference. The foregoing has described the principles, preferred embodiment and modes of operation of the present invention. However, the invention should not be construed as limited to the particular embodiments discussed. Instead, the above-described embodiments should be regarded as illustrative rather than restrictive, and it should be appreciated that variations may be made in those embodiments by workers skilled in the art without departing from the scope of present invention as defined by the following claims.

Ash composition measurements of calcium carbonate and gypsum in paper is accomplished with a dual X-ray sensor system with one X-ray source that is powered at about 5.9 KV and a second X-ray source that is powered at about 4.2 KV. Corresponding detectors measure radiation from the respective X-ray sources that is emitted from the paper. Data derived from the measurements yields the gypsum and crystal water content in the paper. The dual X-ray sensor system can be employed in conjunction with infrared total moisture measurements of paper products being manufactured on a papermaking making machine, which contain gypsum and calcium carbonate, in order to correct for the gypsum crystal water effect.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention concerns a device for dispensing a disinfectant and/or a cleaning agent or a scent into a WC or toilet bowl, and a process for disinfecting and/or cleaning a toilet bowl using such a device. 2. Description of Related Art Maintaining clean and hygienic conditions in toilets and in toilet facilities, especially the toilet bowl, is a constant problem. Scent treatments have been developed for this purpose, but they only address one part of the problem. It is indeed possible to take precautionary measures with newly installed or built toilet facilities, by installing ventilation systems, building in special flushing systems in the toilet bowl etc., but their efficiency is not fully satisfactory, or their effect is delayed, as for example with odor removal. In addition, there is a desire to improve the cleanliness of toilet bowls and reduce odor build-up, even in already existing toilet facilities, where for example the bowl is cleaned by a so-called toilet scrubber, and disinfectant or deodorant agents are added to the flushwater in containers. In other words, these are all improvised measures, that come into effect only after the toilet has been used. In the current state of the art, two patents are known, U.S. Pat. No. 2,760,209 and DE-OS 16 09 234, each of which discloses a device for introducing a liquid disinfectant and/or deodorant into a toilet bowl. In each of these patents, a pouch-like container is located over the rim of the bowl and is squeezed by downward pressure on the toilet seat. The increasing pressure causes the liquid to be released through a tube into the inside of the toilet bowl. Both devices have the disadvantage that when the pressure is released or lifted from the toilet seat, pressure is equalized by the return flow of air through the tube or conveying channel that must at the same time serve to feed the liquid into the inside of the toilet bowl. In addition, inside the pouch-like device or in the portion of the device running under the seat, mechanisms must be provided that will cause the air to expand or be sucked back. It is also a feature of the above devices that at the beginning, when the container is full, a great deal of liquid is sprayed into the toilet bowl, while, when the container is almost empty, very little liquid is released into the bowl. In U.S. Pat. No. 670,916 a dispenser is described whereby liquid is released into a conduit tube when pressure is applied to a nozzle located above, and this conduit tube extends over the upper rim of the toilet into the interior of the bowl. At the end of this tube a balloon is affixed, where the liquid is temporarily stored. A deodorant or disinfectant is then released drop by drop from this balloon over a longer period of time, for the purpose of preventing odor accumulation in the toilet bowl over a longer period of time. The disadvantage of the device as proposed in U.S. Pat. No. 4,670,916, especially in FIG. 4, lies in the fact that, while a deodorant or disinfectant may indeed be released over a longer period of time, this will still be occurring during times when the toilet is not in use at all. And yet, the efficiency of this device is insufficient to overcome or prevent strong odors or soiling when the toilet is being used. SUMMARY OF THE INVENTION Thus, the purpose of the present invention is to provide a device which can be used even in existing toilet installations to meet the demand for cleanliness and odor removal, better and more efficiently than do those described above. In addition, the present invention is intended to provide a device that is as simple as possible, even for existing installations, and easy to refill. With particular reference to the production of odors the invention presents the advantage that odors are neutralized right at the point where they occur. Since, for example, a scent is introduced before the odor arises, then the odor will no longer be noticeable. A process for disinfecting and/or cleansing a toilet bowl is further provided, using a device corresponding to the invention. The invention is explained below in greater detail with reference to the accompanying illustrations. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-section of a device in accordance with the invention, installed on a toilet bowl. FIG. 2 is a top view of the device shown in FIG. 1 from inside the toilet bowl. FIG. 3 is a top view of the devices shown in FIGS. 1 and 2 from the exterior of the toilet bowl. FIG. 4 shows the activating mechanism of the device in accordance with FIGS. 1 to 3, seen from above on the toilet bowl rim. FIG. 5 is a cross-section of a further embodiment in accordance with the invention, encompassing a housing that can be tipped open and that holds an exchangeable reservoir, and FIGS. 6a to 6c show in diagram form, from above, possible nozzle arrangements for dispensing the cleanser or disinfectant. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, the outer wall of the toilet bowl 1 having an upper rim 2, a container 6 is suspended, containing a disinfectant and/or cleaning agent, as, well as an additional aroma or scent. It is also possible to add a decalcifying agent. The container 6 is arranged so that it lies or hangs in a plastic cover 10, that in turn is affixed to the toilet bowl by means of a suction cup 9 at its lower end and a bracket 10' at its upper end. The container, however, can also be installed at a distance from the toilet bowl, for example on the wall of the toilet cubicle, directly next to the toilet bowl. The bracket 10' attached above to the plastic cover 10 in this case extends over the upper rim 2 of the toilet bowl so that the cover 10 is hooked over the upper rim 2 of the bowl. A feed line 12 extends from an upper opening 7' in the container 6 along the underside of the plastic cover 10 over a section 14 which runs essentially underneath the toilet seat 5 to a section 16 of the feed line, whereby the feed line is fastened to the cover 10 or 10' by means of clamps 8 and 20. At the end of the liquid feed line 16 is affixed a dispensing device 18, such as for example a sprinkling or spraying mechanism equipped with a non-return or one-way valve 17. On the other side, the feed line 12 extends through the container opening 7' into the inside of the reservoir 6 through what is preferably an essentially rigid section of piping 12', which is also equipped with a non-return valve 7. In FIG. 2 the device according to FIG. 1 is shown in a top view from inside the toilet bowl, so that essentially only the inner surface 3 of the toilet bowl is visible, along with the upper rim 2 of the bowl with the inwardly suspended portion of the cover 10', by means of which the cover 10 itself is secured on the outer side of the toilet bowl. Inside the bowl, the spray or sprinkling nozzle 18 with its non-return valve 17 is also clearly visible. Depending on the arrangement of the cover 10', items 16, 17 and 18 may also be concealed. All the remaining parts of the device either lie under the cover 10' or are arranged outside the toilet bowl, so that they are shown only with dotted lines. In FIG. 3, the device in accordance with the invention as shown in FIG. 1 is seen from the outer side of the toilet bowl, with the cover 10 not shown, so that the parts of the device are visible. The container 6 with the cleansing or disinfectant liquid can also be secured with overhead hooks and eyelets on the inner side of the cover 10, whereby the suction cup 9 is provided below and also serves to secure the cover 10. In FIG. 4, a section 14 of the tube running underneath the cover 10 or 10' is shown, seen on the rim 2 of the toilet bowl. The tube section 14 is shown in dotted lines, since it is concealed by the cover 10 or 10'. If a person using the toilet now sits down on the seat 5, the section 14 of the liquid feed line is squeezed, so that the two non-return valves 7 and 17 force the liquid in the tube in the direction of the sprinkling nozzle 18, and a dose of the liquid is sprinkled into the interior 3 of the bowl. In this way the device is activated before the toilet is actually used. In the first place, the liquid spray contains a film-forming lubricant or a cleansing agent, which can be either a water-based or oil-based substance, by means of which the normally dry inner wall 3 of the toilet bowl is cleaned and a lubricant film, such as one of silicon, is deposited. This serves to reduce sharply the likelihood of soiling of the toilet bowl in the so-called dry zone, since any deposits will tend to slide downwards because of the lubricating film. Furthermore the liquid spray may contain a disinfectant, so that undesirable bacteria present in deposits in the toilet are largely destroyed. A decalcifying agent can also be added. Finally, the liquid applied may contain some kind of scent or aromatic agent such as perfume, oil of ether etc., so that a scent buffer is created inside the toilet bowl before it is used. Such scents or aromatic agent should preferably be as heavy as or heavier than air, so that it does not escape from the bowl. The dosage forced through by activation of the tube squeeze pump 14 is determined by the length and diameter of the tube running under the toilet seat 5, and preferably amounts to a volume of 0.5 to 2.0 mL. After the toilet is used, when the user gets up from the toilet seat, the tube squeeze pump 14 is released, so that, again due to the effect of the non-return valves 7 and 17, liquid from the container 6 is sucked into the feed line 12, 14, 16. In order for the reed line to be returned essentially to its original shape after every use, the liquid feed line 12, 14, 16 should preferably be made of a silicon material, for which, of course, any plastic material that possesses sufficient properties of resiliency and yet has sufficient resistance to the chemicals and oils that are present can be used. On the contrary, the rigid vertical pipe 12' inside the container 6 should preferably be made of a stiffened or plasticized material, so that the positioning of its open lower end in the container remains as much as possible at the lowest point of the container. Especially suitable materials for this purpose are polypropylene, polyethylene or any other plastic that has sufficient resistance to the chemicals or oils used. The composition of the liquid in the container 6 is determined according to the needs and demands that may be placed on such a cleansing device. Normally a water-alkaline solution with a variable proportion of disinfectant and cleansing agent is used, with the addition of relatively small quantities of aroma or scent, such as oil of ether for example. Other materials such as a decalcifier or enzyme can also be used, however. The liquid can of course be replaced by a powdered material, but in this case the device according to the invention must be adapted in its construction so as to be able to dispense a powdered material. For example, a spray nozzle intended for liquids would not be used in this case, but rather a dispenser designed for dry materials. It can also be advantageous, when using powdered materials, to replace the above described squeeze pump with some other means of ejection, such as a pressurizing device that is functionally connected with the reservoir. In such a case, through the pressure of a person sitting on the ring, or the interruption or release of a photoelectric beam, an electrical impulse can be applied to a pressure cartridge, which in turn builds up a slight pressure in the reservoir, so that the desired dosage of powder is released inside the toilet bowl from the dispenser. This pressure build-up can however also be triggered manually by the user himself, by for example pressing on a button or activating a pedal. The entire device is designed so as to assure it the widest possible application for equipping existing toilet installations, as well as the flexibility to dispense any kind of material that may be required for toilet maintenance. In addition, the reservoir 6 is removably plugged into the feed line 12 in such a way that the container 6 can be exchanged at any time. Of course it is also possible to fill the reservoir 6 up again from a larger refill container. The feed line hose 12, 14, and 16 is also designed so that it can be replaced from time to time. Again, the convenient arrangement of the covering 10 or 10' on the toilet bowl 1 means that the whole device can be removed, eg. for cleaning, or the device can take the form of a so-called one-way or disposable device that can be completely replaced from time to time. FIG. 5 shows, again in cross-section, a preferred application variant of a device in accordance with the invention, corresponding essentially to that shown in FIG. 1, except that here a housing is fitted on the outside of the bowl, affixed for example on the rim of the bowl by a clamp 22' with a mounting plate 23. Using an adjustable clamp 23', the mounting of this housing 22 with its mounting plate 23 can be adjusted to the width of the bowl rim. The housing 22 also has at its lower end a hinged connection 24 with a cover 26, which is arranged over the housing 22 and covers it. Within the housing 22, and sealed off from the outside by the covering 26, a reservoir 6 is arranged, into which, in like fashion to FIG. 1, a preferably rigid portion of the feed line 12' extends, to suck up the cleansing or disinfecting agent. Should the reservoir run dry, the covering 26 (shown in FIG. 5 in dotted lines and indicated as 26') can be tipped outwards, so that the reservoir can be removed from the rigid housing 22. The reservoir can then either be refilled or replaced with a new container, which is inserted in the housing 22, and the covering 26 is again placed over the rigid housing. If so desired, a locking mechanism can be provided so that the reservoir cannot be removed from the device without a special key for opening it. This can be an advantage for use in public lavatories, where as is known any unsecured object is likely to be removed. It is clear from FIG. 5 that in the sealed position, it is almost impossible to lift off the device over the rim 3. Finally it is also possible, and indeed recommended, to correct or adjust the height or thickness of the separator pads normally attached to the toilet seat where it rests on the toilet bowl rim, so that the device according to the invention can be located without hindrance in the space between the rim and the seat. FIGS. 6a to 6c inclusive show various possible nozzle arrangements, for dispensing the cleaning or disinfecting agent in the appropriate manner. For this purpose, a device 31 designed according to the invention is shown installed on the rim 2 of a toilet bowl, with the dispenser nozzle 18 shown diagrammatically on the inside of the so-designed device. The diagram also shows the location of the outflow 33 in the middle of the toilet bowl 1. As shown in FIG. 6a, the dispenser nozzle is designed so that it includes dispenser openings aimed both forwards and backwards around the rim 2 of the bowl, as well as a spray opening aligned centrally in the direction of the outflow 33. FIG. 6b shows a fourth opening that permits dispensing towards the opposite side of the bowl 1. FIG. 6c, finally, shows a dispenser nozzle 18 that is not directly attached to the device 31. This nozzle 18 is connected via a tube 32, and is located at the back of the rim 2 of the bowl 1, so that dispenser openings are provided on both sides around the rim 2, and in addition each opening is pointed obliquely against the two side walls of the bowl. It is important with all dispensing nozzles that they have no openings which are directed at the genital area of the user, since disinfectants and cleaning agents are known to have an effect on sensitive skin. It is also advantageous to use a nozzle that sprinkles rather than sprays, since the flow from a spray nozzle is harder to control. The arrangements of dispenser nozzles illustrated in FIGS. 6a to 6c are of course only examples, and many other arrangements or combinations of the three arrangements shown are possible. The devices according to the invention shown in FIGS. 1 to 6 can of course be changed, modified or varied in any number of ways. Similarly, the cleanser or disinfectant solution used according to the invention can be modified in any number of ways, and adapted to the corresponding demands for such a cleaning fluid. In general, the invention is suitable for dispensing any material or agent that is intended for use in toilet maintenance. In addition, any installation and any container can be used as the dispenser and reservoir as long as they are suitable for dispensing and storing the above-mentioned materials in or on a toilet bowl. The essential feature of the invention is that a small amount of a cleansing or disinfecting agent or a scent is dispensed into the inside of a toilet bowl from a reservoir through a propulsion device located underneath the toilet seat, before the toilet is used. The dispensing or releasing process is triggered preferably by the action of a weight on the toilet seat, for example by the pressure exerted by a toilet user. The dispensing action can also be triggered however in any way desired, such as through a photoelectric beam, an electrical switch or manually by activating a button or pedal.

A device for dispensing a disinfectant, cleaning agent and/or scent into the interior of a toilet bowl includes a reservoir for the disinfectant, cleaning agent and/or scent. The reservoir has suspension elements fitted to the rim of the bowl or the outside of the bowl and a feed line passing over the rim and into the interior of the bowl. A dispenser element is fitted to the feed line in the interior of the bowl for dispensing a given quantity of the disinfectant, cleaning agent and/or scent into the interior of the bowl. An actuator is fitted to the reservoir, the feed line or the dispenser element and operated by the user of the toilet bowl to dispense a given quantity of disinfectant, cleaning agent and/or scent. The feed line has at least one non-return valve for preventing the disinfectant, cleaning agent and/or scent from flowing back into the reservoir.

FIELD OF THE INVENTION The present invention concerns new drill stems intended for sinking shafts in the ground, especially for the oil and gas industry, containing near the upper part so each stem element a zone intended to serve as a base for slips that support the drill string assembly. BACKGROUND OF THE INVENTION It is known that during emplacement of a drill string it is necessary to maintain the upper part of the string with slips that usually include self-gripping jaws whose internal part has serrations or teeth that rest against the drill stem near the threaded female coupling and whose external part has a conical shape which meshes with a piece of corresponding shape to ensure self-gripping of the slips, thus holding the drill string that is suspended over its entire height. In the technique now employed the teeth on the inner face of the slips that rest against the drill stem produce on the surface of the latter plastic deformations that are conveyed by a succession of notches. This causes a substantial reduction in resistance of the stem at the location where the self-gripping slips are applied, causing fatique rupture of the stem at this site, especially in the case where slanted holes are being drilled. In other words, the notches, generally angular in shape, made by the slips on the drill stem substantially reduce its fatigue resistance which requires premature replacement of this stem or causes accidents. SUMMARY OF THE INVENTION The present invention seeks to overcome this and other drawbacks by making on the part of each element of the drill stem near the threaded female coupling a surface of revolution whose generatrix has a shape complementary to that imparted to the support surface of the self-gripping slips referred to above. The surface of revolution on the upper part of the drill stem element is advantageously made by knurling or burnishing, which on the one hand permits achievement of the desired profile without a loss of material and, on the other hand, owing to wear hardening of the surface part of the drill stem, imparts to the latter better fatigue resistance. According to another version the profile according to the invention can be obtained by mechanical wear, preferably followed by treatment, for example, by blasting to increase the fatigue resistance. In addition, the profiles of the surfaces of revolution so obtained can have a given depth merely by reducing the thickness of the tube by about 1/2 this depth, this being due to rebound of metal toward the exterior. The profile of the surface of revolution made on the element of the drill stem preferably has a circular shape at the bottom of the hollow part with the largest possible radius. According to the invention it is advantageous to use a disymmetric profile, the upper part of the hollow profile preferably having a line that makes an angle between 10° and 45°, preferably about 30°, with a perpendicular to the axis of the stem, whereas the lower part of the profile preferably has a line that makes an angle between 45° and 80°, preferably about 60°, with a perpendicular to the axis of the stem, the angle between the upper part and the lower part of the profile being between 55° and 125°, preferably about 90°. The total depth of the profile can be between 1 and 2 mm, preferably about 1.5 mm. The profile described above can be repeated along the part of a drill stem element near the inside threading over a length of about 100 to 900 mm, preferably over a length of about 600 mm at 1 to 10 mm intervals, preferably about 5 mm intervals (i.e., a profile every 5 mm). The slips that hold the drill string have a complementary profile made with a minimum number of teeth of about 20 in order to mesh easily on the profile of the drill stem element without producing on the stem contact pressures greater than the elastic limit of the stem metal. BRIEF DESCRIPTION OF THE DRAWINGS In order to offer a better understanding of the invention an embodiment depicted on the enclosed drawing now will be described by way of nonlimiting illustration. In this drawing: FIG. 1 represents a schematic view of a device according to the state of the art to support a drill string; FIG. 2 represents part II of FIG. 1 on a larger scale and modified according to the invention; FIG. 3 is a view on a still larger scale representing the profile of the surface of revolution made according to the invention on the upper part of the drill stem element to receive the self-gripping slips; and FIG. 4 is a schematic view representing a knurling wheel that makes the surfaces of revolution according to the invention on the elements of the drill stems. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS We see in FIG. 1 how the upper end of the drill string 1 is supported by means of slips 2 which possess sharp teeth 3 on their internal faces that rest against drill stem 1 and have on their external face a conical surface 4 that cooperates with a conical surface 5 of corresponding shape located on a plate 6. One can understand under these conditions how slips 2 that are, say three in number, distributed on the periphery of the drill stem, are entrained downward by the weight of the drill stem transmitted by teeth 3 whereas the conical surfaces 4 and 5 force the slips 2 inwardly toward the drill stem for a self-gripping effect. Considering the substantial weight that the drill string can reach, one can see that considerable radial forces are exerted on the drill stem so that the teeth 3 dig very strongly into the surface of the drill stem, causing notches at the sharp edges that substantially reduce the fatigue resistance of the elements of the drill stem. FIG. 2 depicts part II of FIG. 1 modified according to the invention. In FIG. 2 we find plate 6, slips 2 as well as the element of drill stem 1. According to the invention a special profile is imparted to the external surface of the element of drill stem 1 which is intended to cooperate with slips 2, the internal surface of these slips that rest against the drill stem having a complementary shape. The profile of the surface of the stem advantageously possesses an axial length greater than that of the slips in order to permit easy engagement. FIG. 3 shows on a larger scale the external profile of the surface of revolution made according to the invention on the drill stem. Drill stem 1 is again found in this figure where broken line 7 represents the external surface of the element of the drill stem before the profile according to the invention is imparted to it. As is seen in FIG. 3, the depth of the profile is distributed on both sides of line 7, which enables one to obtain a profile of given depth by reducing the thickness of the stem metal by only about half. In the embodiment shown, the profile has a toric shape 8 on the inside in which the radius of the generator circle, which is as large as possible, is between 0.2 and 2 mm, for example. The toric part 8 is extended on its upper part by a tapered zone 9 whose generatrix makes an angle A between about 10° and 45°, preferably about 30°, with a plane perpendicular to the axis of the drill stem. The toric part 8 is extended on its lower part by a tapered zone 10 whose generatrix makes an angle B between about 45° and 80°, preferably about 60°, with a plane perpendicular to the axis of the drill stem, the angle made between the generatrices of cones 9 and 10 being between about 55° and 125°, preferably about 90°. The interval, i.e., the distance separating two profiles arranged side by side longitudinally, which is represented at 11 in FIG. 3, is generally between 1 and 10 mm, preferably about 5 mm. The depth of the profile depicted at 12 in FIG. 3 can be between about 1 and 2 mm and it is preferably close to 1.5 mm, which corresponds to a reduction in useful thickness of the drill stem of only about 0.7 mm. The profile depicted in FIG. 3 is repeated over a length of about 100 to 900 mm of the drill stem, preferably over a length of about 600 mm in order to impart surfaces of revolution having the described profile over these same lengths. The self-gripping slips 2 have a surface of revolution of complementary shape on their internal surface and they contain at least 20 teeth whose shape corresponds to that of the grooves described above. FIG. 4 schematically depicts rollers 13 that permit making of the surfaces of revolution created according to the invention on the drill stems by knurling according to a conventional technique. In the embodiment of FIG. 4 rollers 13 are assembled on an axis 14, held between a collar and a counter support 15. The surface of revolution according to the invention is obtained by allowing rollers 13 to act successively at different sites on the drill stem. One sees that according to the invention it is possible to make surfaces of revolution simply and at lower cost on drill stems, said surfaces having profiles corresponding to the profiles imparted to the internal surface of the self-gripping slips. In this manner one can easily maintain drill strings without a significant reduction in their mechanical resistance, especially their resistance to alternating stresses, preserving excellent fatigue resistance properties in the gripping zone. It is understood that the embodiment described above is given merely as an example and in no way limits the invention. In particular, the surfaces of revolution made on the drill stems according to the invention can have profiles different from that described, provided that these profiles are not made with sharp angles or small radii of curvature that would increase the fragility of the drill stem. Thus, the surfaces of revolution according to the invention can have profiles of circular shape or elliptical shape with a major axis parallel or inclined relative to the axis of the stem. It also goes without saying that the surfaces of revolution made according to the invention can be obtained by processes other than knurling or burnishing as described above. In the case of machining by elimination of metal it is advantageous to provide surface treatment, for example, blasting. Finally, the profiles according to the invention can also be made on all the elements or accessories used in drilling.

The invention disclosed herein concerns a drill stem intended for sinking shafts in the ground, especially for the oil and natural gas industry. It has on its outer periphery a surface of revolution providing a succession of hollow profiles with a rounded shape relative to the axis of the stem, said surfaces for revolution being adapted to rest against the internal faces of complementary shape of self-gripping slips which ensure holding of the drill string.

CROSS-REFERENCED TO RELATED APPLICATIONS This application is a non-provisional application of Application No. 61/000,485, filed Oct. 26, 2007 and claims priority from that application which is also deemed incorporated by reference in its entirety in this application. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not applicable BACKGROUND OF THE INVENTION I. Field of the Invention The present invention relates to a method and apparatus for growing and conditioning tissue engineered medical products and in particular to a method and apparatus for a servocontrolled bioreactor with a dynamic pressurization system and a chamber with an integrated nutrient reservoir for conditioning tissue engineered medical products (TEMPs) in the orthopedic, secretory organ and vascular areas. TEMPs can include, without limitation, various types of tissue in several areas. Within the orthopedic area TEMPS can include: cartilage, bone, meniscus, ligaments, tendons, muscle, and other musculo-skeletal devices. Within the secretory organ area TEMPs can include liver, kidney, skin and other organs. Within the vascular area TEMPs can include, but are not limited to, heart valves, blood vessels, and cardiac patches. Other TEMPs can include: cornea, bladder, urethra, small intestine or any other tissue that might be replaced in the body. Tissue engineering is a rapidly growing area that seeks to create, repair and/or replace tissues and organs by using combinations of cells, biomaterials, and/or biologically active molecules. It is an interdisciplinary field that integrates aspects of engineering, and other quantitative sciences, with biology and medicine. Research and technology development in tissue engineering promises to revolutionize current methods of health care treatment and significantly improve the quality of life for millions of patients. As one indication of the scope of the problem that tissue engineering addresses, worldwide organ replacement therapies utilizing standard organo-metallic devices consume 8 percent of medical spending, or approximately $350 billion per year. Organ transplantation is another option for replacing damaged or diseased tissue, but one that is severely limited by donor availability. Tissue-engineered products hold the promise for true functional replacement. However, despite early laboratory successes, few functional tissue engineered products are currently available for clinical use. Researchers have sought to develop living alternatives to traditional “man-made” medical devices. These TEMPs use the patient's own cells to create replacement devices that can be cultured and grown once they are implanted. Through design and fabrication of biomaterials and specification of cells or biomolecules, it is hoped that TEMPs will play a major role in many future regenerative medicine therapies. In the orthopedic area considerable energy is being expended on the development of tissue engineered cartilage, meniscus, bone, ligaments or tendon replacements. Likewise, similar efforts are being made to develop new replacements for heart valves, arteries, heart muscle tissue and venous valves. Tissue engineered replacements for secretory organs such as the liver, kidney and skin also hold great promise for future therapies. Tissue engineered skin replacements are already available and are dramatically improving the outcomes for patients with diabetic ulcers, as well as burn victims and those undergoing certain cosmetic therapies. The field of tissue engineering in recent years has included the development of bioreactors which provide a means of conditioning a developing tissue by applying mechanical stresses to a construct (cells or cell seeded substrate while circulating nutrient media around and or through the construct. Cells and tissues grown in bioreactors able to mimic physiological conditions including mechanical forces have enhanced tissue development, mechanical properties and function. These bioreactor systems typically include a bioreactor chamber coupled to a device which generates motion and applies forces, pressures and or deformations to the tissue construct via a mechanical feed-through (push or pull rod). Additionally, these systems typically include a separate reservoir that contains a nutrient media for sustaining the cells within the tissue construct. The reservoir is often connected to the bioreactor chamber via tubing and a mechanical pumping system. The biochemistry of the nutrient media can be maintained by exposing it to the environment that is created within an incubator system. The incubator maintains the temperature, as well as gas concentrations (CO 2 , O 2 , etc.). The exposure of the media to the environment is often accomplished by placing a vented reservoir directly in the incubator or by circulating the media through gas permeable tubing located inside the incubator. Gas concentrations can also be bubbled through the media to maintain appropriate culture conditions. II. Related Art Other bioreactor systems have addressed aspects of the need for an apparatus dedicated to growing and conditioning tissue engineered medical products. As will become apparent, the present device described in this patent application surpasses those systems in several respects. Spaulding et al. (U.S. Pat. No. 5,330,908), (U.S. Pat. No. 6,001,643) and Schwartz (U.S. Pat. No. 5,437,998), (U.S. Pat. No. 5,665,594) disclose bioreactor systems that operate at ambient pressure and in which mechanical stresses to the cells are applied by rolling the chamber about its cylindrical axis. Conversely, the bioreactor system of the present invention applies a static or varying pressure to the chamber and subsequently the tissue construct within while the chamber is agitated via a multi-axis motion device. Dunkleman et al. (U.S. Pat. No. 5,792,603), Peterson et al (U.S. Pat. No. 5,846,828) and Vilendrer et al (U.S. Pat. No. 7,348,175) disclose bioreactor systems for vascular grafts in which an alternating or varying flow or backpressure from an external media storage device is provided via a tube and pumping system. Control of the flow and/or back pressure is provided by an external flow pump. Whereas, in the present system, the sealed chamber and media reservoir are combined thus eliminating the need for an interconnecting tube to create flow. Additionally, pressurization in the present system may be provided directly via a high pressure air source and servovalve controlled by a microprocessor servocontrol system which supplies specific air pressures to one side of a deformable membrane. As the membrane deforms the pressure is transferred to the interior of the chamber. Applegate et al. (U.S. Pat. No. 5,843,766) discloses a bioreactor system for grafts with inlet and outlet ports for evenly distributing media flow across and generally parallel to the tissue substrate that also requires a separate external nutrient fluid reservoir. In the present system, the agitation of the chamber and deformation of the membrane aid in convective mass transport. Amrani et al. (U.S. Pat. No. 5,902,937) discloses an in vitro testing system for testing blood/tissue interaction that utilizes twin chambers with top and bottom tissue membranes and an internal conduit for conducting blood between the chambers. Blood flow actuation is provided by pistons that alternately depress the membranes on each chamber to displace blood from one chamber to the other. Naughton et al. (U.S. Pat. No. 6,008,049) discloses a diffusion gradient bioreactor system for conditioning tissue engineered liver whereby the tissue is exposed to two nutrient flows. The primary purpose of their device is to move solutes through the device via flow. With the present system only one sealed chamber is needed and it is not interconnected with another chamber to create flow. Also, as indicated above, pressurization in the present invention may be provided directly through a deformable membrane. The high pressure air source is controlled via a microprocessor-controlled servovalve. Flatt et al (U.S. Pat. No. 6,060,306) discloses a bioreactor chamber with a substrate that is sealed to the sides of the chamber. Using various mechanical actuation means, a pressure differential is created across the substrate to create a fluid flow through it. In the present system, the substrate is not sealed to the sides of the chamber so any applied pressure does not create a differential across the substrate to create a fluid flow through it. Peterson et al (U.S. Pat. No. 6,121,042) and Carpentier et al (U.S. Pat. No. 6,210,957 B1) disclose bioreactor systems that provide flow about a substrate that is attached to a structure. These systems pump fluid through the chamber using inlet and outlet ports, or actuate the structure to control media flow characteristics around the substrate. In contrast, the substrate of the present system is not attached to a structure but is free to move within the chamber nor is fluid pumped through the chamber to create controlled media flow characteristics. Mechanical agitation of the chamber to enhance fluid mass transport is provided via the shaking motion of a mechanical shaking system and a hydrostatic stress may be provided by pressurization of the membrane as indicated above. Smith et al (U.S. Pat. No. 6,171,812 B1) and Vilendrer (U.S. Pat. No. 7,410,792 B2) further disclose a bioreactor system that has means for perfusion and application of forces to the substrate within the bioreactor chamber. In the present system, neither of these forces within the chamber is explicitly provided. Takagi et al (U.S. Pat. No. 6,432,713 B2), (U.S. Pat. No. 6,599,734 B2), (U.S. Pat. No. 6,607,917 B2), (U.S. Pat. No. 6,921,662 B2) describes bioreactor systems which utilize a sealed chamber that is interconnected to a medium reservoir via a tube or circuit. Pressurization of the chambers is provided via actuator driven pistons and control of the system is accomplished using regulators and timers or a microcomputer that turns various valves on at the appropriate times. Tagaki et al (U.S. Pat. No. 7,144,726) also describes a bioreactor chamber with fluid port and a magnetically driven pressing plate for creating pressurization within the chamber. These references do not suggest the use of a sealed combined chamber. While some of the above described systems have worked in certain applications, there remains a need in the art to simplify the method and apparatus for growing and conditioning tissue while maintaining environmental control. SUMMARY OF THE INVENTION The present invention addresses a need in the art for a method and apparatus for growing and conditioning tissue and other needs which will be appreciated by those skilled in the art upon reading and understanding the teachings of the present invention. The subject matter of the present development relates to a bioreactor system for growing and conditioning tissue in various embodiments including a bioreactor system for three-dimensional tissue growth and stimulation. This system features a bioreactor tissue growth chamber capable of dynamic pressurization and an integrated fluid culture media reservoir which does not require a flow loop. In accordance with the present invention, it has been discovered that beneficial mechanical stress can be applied directly to a construct by deforming a membrane on one or more surfaces of the tissue growth chamber without the need for mechanical feed-throughs. Additionally, integrating the reservoir within the bioreactor chamber can eliminate the culture media flow loop and associated tubing. Consequently, the present invention features a bioreactor or tissue growth chamber that couples the stress application with the nutrient media exchange mechanism in one unit. One embodiment includes a bioreactor system for growing and conditioning tissue for research or future implantation in a patient. The system includes one or more tissue growth chambers for growing and conditioning the tissue and each tissue growth chamber includes a housing which is a fluid culture media reservoir for growing and conditioning at least one tissue construct that may include one or more substrates for growing three-dimensional tissues. The tissue growth chamber includes separate ports for introducing pressurized air or other gas and fluid culture media. The bioreactor system further includes at least one pressurized gas space proximal to or contained within the chamber and a control system to selectively control the pressure and temperature of the gas (normally air) from the source of pressurized gas which is transmitted to the tissue growth chamber via a non gas-permeable membrane to create a dynamic hydrostatic state of stress to developing tissues or cells. In this manner, a programmable static or dynamic pressure profile can be delivered. A substrate on which the three-dimensional tissue construct may be grown may include bio-compatible three-dimensional framework having interstitial spaces bridgeable by cells. The one or more tissue growth chambers may be mounted on a shaker to agitate the culture media to enhance convective mass transport. At least one device for facilitating gas exchange within the chamber is provided to maintain the appropriate gas concentration (atmosphere). This may be a gas-permeable membrane between the chamber and a desired gas environment. The embodiment may include a system for distributing pressurized air and mechanically agitating tissue growth chambers which are designed to be contained in an incubator and interface with a computer-controlled system and a source of dried, heated air, normally external to the incubator. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: FIG. 1A shows a bioreactor chamber according to one embodiment of the present invention; FIG. 1B is a cross-sectional view of the bioreactor chamber shown in FIG. 1A ; FIG. 2 shows a schematic functional diagram of a microprocessor servocontrolled bioreactor system according to one embodiment of the present invention; FIG. 3 illustrates one embodiment of a pressure manifold assembly shown schematically in FIG. 2 including various components that are mounted to the manifold; FIGS. 4A and 4B depict assemblies that fit within the incubator according to one embodiment of the present invention, FIG. 4A showing a manifold assembly and FIG. 4B showing bioreactor chambers, shaker plate and shaker; FIG. 5 depicts the assemblies of FIGS. 4A and 4B as assembled in an incubator; and FIG. 6 depicts an entire system as it may be operated in a laboratory. DETAILED DESCRIPTION In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. The embodiments shown and described are meant as examples only and are not intended to limit the scope of the concepts of the invention in any manner. Illustrative embodiments are described in sufficient detail to show a full grasp of the invention by the inventors and to enable those skilled in the art to practice the invention. It will be understood that the embodiments may be combined, or that other embodiments may be utilized and that structural, logical and electrical changes may be made without departing from the spirit and scope of the present invention. The following detailed description provides examples, the scope of the present invention being defined by the appended claims and their equivalents. The present disclosure relates to a method and apparatus for a bioreactor system for three-dimensional tissue stimulation featuring dynamic pressurization and an integrated reservoir which does not require a flow loop. This will be described with reference to FIGS. 1A, 1B, 2, 3 and 4 . FIG. 1A shows a bioreactor or tissue growth chamber, generally at 100 and FIG. 1B depicts a cross-sectional view of the tissue growth chamber 100 of FIG. 1A . One or more of these chambers may be used with the tissue growing and conditioning system of the invention. In one current embodiment, for example, up to 12 chambers can be included. As seen in FIG. 1B , a tissue construct 102 has been created and placed into a main hollow chamber or media cavity 104 defined by a main housing 106 which is closed by upper and lower endcaps 108 and 110 , respectively. The term “construct” may refer to the tissue itself or a tissue/substrate combination. The chamber media cavity 104 is further sealed on both upper and lower ends with membranes as at 112 , 114 , respectively. In this embodiment, membrane 112 is a non gas-permeable material and membrane 114 is gas-permeable and communicates with vent holes for gas exchange shown at 119 to facilitate gas exchange between the chamber media cavity 104 and a desired external gas environment. Other chamber embodiments may include different membrane configurations utilizing as few membranes as none or as many as necessary to achieve the desired media cavity pressurization and or media gas concentration. The tissue construct is housed in the tissue growth chamber but is not attached to the chamber. The substrate may be permeable and the culture media can circulate through the substrate to contact all surfaces of the construct. The substrate may be fabricated from a material designed to facilitate three dimensional tissue growth and include a biocompatible three dimensional framework 103 that includes interstitial spaces 105 that are bridgeable by cells (not shown). That substrate material may be biological in nature and be comprised of extracellular matrix, decellularized tissue, native tissue explants, polymer matrices, woven fiber meshes, porous ceramic lattices, porous metal structures, or any other type of material that supports cell growth and differentiation. The tissue construct may also be substrate free, and be comprised of cells alone. The tissue construct is three dimensional in nature and may be tissue-engineered cartilage, skin, bone, liver, lung or some other tissue-engineered graft or medical device. It will be appreciated that the tissue can be grown without using a substrate as by using a cell suspension or aggregate of cells. The tissue growth chamber membranes may be either gas permeable or non gas permeable and are made out of a material that permits elastic deformation. The membranes may either be flat or curved or fabricated with a specific geometry to cover and seal the media cavity appropriately. The membranes 112 , 114 are held in place by a pair of opposed endcaps/support structures at 108 , 110 , respectively, that sandwich/clamp the membranes between the endcaps and the main housing sidewall 106 . Optionally, and particularly, if the upper membrane is relatively stiff, spaced opposed o-ring members as at 116 and 118 or some other equivalent sealing mechanism, such as glue, soft deformable sealant, tape, caulk, silicone grease, or the like, may be used to seal the membrane 112 between the chamber main housing sidewall 106 and the endcap 108 . The membranes 112 , 114 may also be fixed, bonded, or a permanent component of either the endcaps 108 , 110 or the chamber main housing sidewall 106 . Sealing mechanisms may also be provided for the membrane 114 between housing sidewall 106 and endcap 110 . The endcaps themselves are held in place by the compressive action of a plurality of fasteners that may be bolts 120 ( FIG. 1A ) that are threaded through washers 122 and endcap 110 and are threaded into corresponding openings in opposite endcap 108 at 124 . It will be appreciated that the bolts may be replaced by other suitable fastening elements such as, for example, threaded tie rods provided with nuts on either end. Alternatively, the endcaps 108 , 110 may also be held and sealed against the membranes 112 , 114 and chamber main housing sidewall 106 via threaded connections or some other clamping means. Access is provided to the chamber after it has been sealed, such that media may be deposited/injected into the chamber media cavity 104 via a media port 130 (inlet/outlet access port) which includes an access opening into the chamber media cavity 104 . The media port 130 includes a media fitting 132 , o-ring seal 134 and plug fitting 136 . The o-ring seal 134 in some embodiments may be replaced by any of several other sealing techniques and devices including Teflon® (polytetrafluoroethylene) tape, silicone grease, interference thread fit, glue, epoxy, caulk, or any other satisfactory sealing mechanism. The media port may also be machined, molded or directly fabricated as an integral part of the chamber main housing. Depending on the application, the chamber may be constructed without an access port or provided with as many media ports as is required for injecting media and bleeding out air. For some applications, it may be desirable for air to remain in the chamber. Once the chamber cavity 104 is filled or partially filled with media, the media fitting 132 is closed as with plug fitting 136 . An optional additional port 138 may be provided in the chamber main housing to accommodate a pressure transducer to verify and monitor the internal chamber pressure. The application of a hydrostatic state of stress is an important aspect of the operation of the bioreactive chamber. Accordingly, a pressurized gas fitting 138 is provided to supply controlled pressurized gas (or air) into a pressurized gas space 140 in endcap 108 . In the embodiment of FIGS. 1A and 1B , the pressurized gas fitting 138 is a quick-disconnect fitting, but any type of fitting that allows the user to connect a pressurized air/gas supply to the chamber could be used. The pressurized gas space is open to membrane 112 such that a change in gas pressure in space 140 causes Membrane A 112 to deform and increase the pressure in the chamber media cavity 104 . In the illustrative embodiment, membrane 112 is non-permeable and membrane 114 is permeable. Therefore, gas exchange can occur through membrane 114 and vent holes 142 provided in endcap 110 . Of course, in the event that no gas exchange is required, as is the case in certain applications, both membranes could be non gas-permeable. In certain other applications, the addition of pressurized gas directly to the inside of the chamber may be desired and, in such embodiments, membrane 112 is selected from gas permeable materials and membrane 114 is of a non gas-permeable material. In that arrangement, the pressurized gas may contain the appropriate concentrations of gas species needed for successful cell culture. FIG. 2 shows an embodiment of a dynamic pressurization and control system, generally 200 , suitable to be used to create a dynamic hydrostatic stress state in the chamber 104 of FIGS. 1A and 1B for the tissue construct 102 . The pressurization system, as will be described below, includes a Pressure Pack shown in dashed lines at 204 for creating a pressurized supply of air or other system gas which may be generally in the 80-150 psig range and to provide a vacuum in the 5 psia range, however, any pressure and vacuum range that would be required is acceptable. Air to be pressurized starts out as ambient air that is drawn into the system through a filter 206 and then warmed by an associated heater 208 , which may be a tubular air heater as in the illustrative embodiment. The warmed air travels to a proportional valve 210 attached to a manifold assembly indicated by a dotted line at 212 located inside the incubator 202 . The proportional valve 210 controls the amount of air that is drawn past a vacuum gauge 214 into a vacuum tank 216 , through a compressor 218 and into a pressure tank 220 . The compressor 218 , in turn, is coupled to an AC motor 222 which is controlled by an AC motor inverter drive 224 which controls the motor at a constant rpm. Pressure tank 220 is used as an accumulator for storing pressurized air supplied by compressor 218 . A pressure relief valve is provided at 226 with integrated pressure gauge 228 . The pressure relief valve may be set to any desired pressure and is normally set to about 100 psig (or any other appropriate pressure limit) as a safeguard to prevent over pressurizing the system. A pressure transducer 230 is connected to the pressure tank and to a controller 232 which is also connected to control proportional valve 210 to complete a feedback loop with control software to maintain a desired pressure in the tank 220 . In this manner, if the pressure in the tank 220 falls below the desired pressure level, the controller 232 sends a signal to proportional valve 210 to open incrementally to increase air flow to the compressor and thereby increase the tank pressure. Conversely, if the pressure in the tank is above the desired pressure level, the controller signals the proportional valve to begin to close, which decreases the available air that can be compressed and the air pressure in the tank decreases. Prior to being supplied to the incubator bioreactor chamber, the pressurized air is passed through a filter 234 (or series of filters) to remove any particles and then through an air dryer 236 to prevent moisture from accumulating in the line. Moisture is expelled out of the dryer into the ambient air via a purge line 238 . Upon entering the incubator, the pressurized air travels through the manifold assembly 212 . A three-way ported servovalve 240 when commanded in one direction ports the pressurized air supply to a gas distribution manifold 244 which, in turn, subsequently supplies pressurized air to the chambers 100 . Pre-drying the air reduces the potential for corrosion of the servovalve 240 . Prior to encountering the servovalve 240 , the air is passed through an air heater 242 wherein it is heated to match the temperature inside the incubator. A pressure transducer 246 on gas distribution manifold 244 monitors the pressure inside the manifold 244 . If the servovalve 240 is in a completely closed position and the air supply to the gas distribution manifold 244 is blocked, as shown in FIG. 2 , the air slowly escapes out of a bleed valve 248 . The servovalve 240 is controlled via an electric voltage signal output from the system controller 232 . The system controller 232 monitors the pressure in bioreactor chambers 100 via pressure transducer 246 or optional pressure transducer 249 through port 247 in chamber 100 and sends a control signal to the servovalve 240 to maintain the desired pressure waveform. Additionally, the controller 232 can be used to monitor the pressure output signal of an optional pressure transducer 250 which is connected directly to a chamber 100 and can be used for calibration purposes to correlate the pressure in chamber 100 with the pressure in the gas distribution manifold 244 . Optional pressure transducer 249 can also be used as an alternate feedback device to control the servovalve 240 mounted on the gas distribution manifold 244 . When the servovalve 240 is commaned to provide pressure, high pressure gas enters the gas distribution manifold 244 and pressurizes the chambers 100 . When the servovalve is commanded to reduce pressure, it connects manifold 244 with the vacuum tank 216 as needed to reduce the chamber pressures to a lower value. The pressure command can take any of many forms to control the pressure supplied to the manifold on a steady or time-variable basis including a static setting, a sinusoidal, trapezoid, ramp or physiologic waveform. A personal computer 252 provides a user interface for communicating with the controller 232 . Additionally, controller 232 can be configured to communicate conditions within the bioreactor system to the outside world as via a data acquisition system (DAQ) 254 and alarm 256 . Advantageously, in this manner, using a non gas-permeable membrane 112 , the pressurized air supply can be kept separate from the gas mixture inside the incubator, yet produce the desired hydrostatic pressure effect on growing tissue. It will also be appreciated that the configuration of FIG. 2 could also be constructed with all (or some combination of) the components of the manifold assembly located outside the incubator. In embodiments for certain applications, it is acceptable for the air from the incubator to mix with the pressurized air supply. In such embodiments, inlet filter 206 and bleed-valve/silencer 248 can be moved inside the incubator 202 and the inlet air would not need to be heated between the filter 206 and the proportional valve 210 . FIG. 3 illustrates one embodiment of a pressure manifold assembly including gas manifold components shown schematically in FIG. 2 . The manifold assembly is mounted on an incubator shelf 300 designed to slide into a standard incubator shelf holder (not shown). High pressure air from the pressure pack is received in a servovalve manifold 302 through a high pressure inlet fitting 303 and is routed through servovalve 240 where it is either diverted to a high pressure outlet 304 , or directed to the gas distribution manifold 244 . In the manifold, pressure is set to the desired dynamic pressure using feedback from the pressure transducer 246 which is connected to the center of the gas distribution manifold 244 . The pressurized air/gas exiting the manifold is supplied to a plurality of tissue growth chambers 100 through a plurality of manifold distribution fittings 305 which may be connected by non gas-permeable chemically inert tubing (not shown) to each chamber. As indicated, the pressure in the chambers 100 may be reduced as needed by commanding the servovalve 240 to connect to the vacuum tank 216 which rapidly reduces the air/gas pressure until the appropriate pressure has been reached. Air/gas exits the servovalve by traveling through a vacuum outlet fitting 305 connected to vacuum tank 216 . It will be recognized that in a different embodiment, an additional air supply may be required to maintain an appropriate pressure, therefore a secondary air inlet (in addition to the proportional valve inlet 210 ) may be necessary. Accordingly, the servovalve manifold 302 in FIG. 3 includes a secondary vacuum inlet that has been shown sealed with a plug at 306 , which can be used if larger airflow is necessary. FIG. 4A illustrates another view of a mounted manifold assembly 212 mounted on an incubator shelf 300 . The shelf is carried on a pair of support legs 310 and 312 with attachment feet 314 and 316 , respectively which are designed to mount in an incubator as shown in FIG. 5 . FIG. 4B shows a plurality of bioreactor chambers 100 mounted atop a Belly Dancer Shaker System 400 designed to be contained in an incubator. Additional openings are provided at 402 to accommodate additional chambers. The shaker system is one built by Stovall Life Science, Inc. of Greensboro, N.C. but equivalent systems may be used. The shaker provides a means of selectively cyclically agitating the cell culture media to enhance nutrient mass transport through the construct and gas transfer across the gas permeable membrane 114 ( FIG. 2 ). The shaker system includes a shaker module 400 and a connected shaker plate 404 or platform on which are mounted the plurality of chambers 100 . It will be appreciated that the agitating movement of the bioreactor chamber creates varying motion in the nutrients containing fluid culture medium which may aid cell seeding on the substrate or help facilitate cell aggregation and adhesion as well as the transfer of nutrients within the substrate. The movement of the chamber may further generate varying multi-axial stresses in the tissue construct which provides added stimulation which may enhance tissue development, mechanical properties and function. FIG. 5 depicts the assemblies of FIGS. 4A and 4B as assembled in an incubator 202 where the actual tissue growth is carried on. Such incubators are available commercially and, of course, include their own temperature control systems to create the proper temperature environment for carrying on the tissue growth. FIG. 6 depicts a typical view of an entire system, including all the auxiliary devices as would be typically set up in a tissue growth laboratory. Note that the pressurized air supply or pressure pack 204 , together with heaters 208 , 242 , filter 206 and air drier 236 are situated outside the incubator 202 , but are connected to the incubator through tubing connections as shown. Auxiliary gas tanks 600 , 602 are also provided and are generally connected to the incubator gas inlet ports, but may be connected to media inlet ports of tissue growth chambers inside the incubator 202 . Electrical control is supplied by controller 232 in combination with a personal computer. Both components may be programmed in any manner desired to control the tissue growth environmental conditions. Other embodiments may use alternative control platforms including but not limited to: Programmable Logic Controllers, Personal Digital Assistants, mini computer, super computer, etc. The embodiments provided herein are intended to demonstrate representative embodiments of the present subject matter. Variations in structure and design are possible without departing from the scope of the present invention, which is defined by the appended claims and their equivalents. Other embodiments for bioreactor configurations may include the combination of various elements and configurations as provided herein. This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use embodiments of the example as required. However, it is to be understood that the invention can be carried out by specifically different devices and that various modifications can be accomplished without departing from the scope of the invention itself.

A bioreactor system for growing and conditioning tissue for research and implantation in a human or animal body is disclosed which includes one or more tissue growth chambers for growing and conditioning tissue, each chamber being defined by a housing and providing a fluid culture media cavity which can act as a reservoir. A construct for growing three-dimensional tissues is housed in each tissue growth chamber. Each chamber is connected to a source of pressurized air for applying a controlled pressure to the chamber media cavity. The tissue growth chambers can be mounted on an agitation device such as a shaker system which enhances mass transport within the chamber media cavity. A control system is provided to control the pressure and temperature of the pressurized gas delivered to the chamber media cavity and subsequently to the tissue construct.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of controlling an RF pulse in a magnetic resonance imaging apparatus and a system for practicing the method. 2. Description of the Related Art In a magnetic resonance (MR) phenomenon, an atomic nucleus having a magnetic moment in a static field absorbs or emits an electromagnetic wave having a specific frequency by resonance. A resonance frequency (Lamor frequency) ν 0 of the atomic nucleus is represented by the following equation: ν.sub.0 =γH.sub.0 /2 (1) where γ is the magnetogyric ratio unique to the type of atomic nucleus, and H 0 is the intensity of a static field. An MRI (magnetic resonance imaging) apparatus for diagnosing the inside of a subject to be examined by utilizing the MR phenomenon applies a slicing gradient field and an RF (radio frequency) pulse to the subject placed in a uniform static field. A nuclide of interest in the subject is selectively excited to generate an MR signal. In order to add position information to the MR signal, a phase encoding gradient field is applied in a direction perpendicular to the directions of the slicing and phase encoding gradient fields. The MR signal generated in the subject is received by an RF coil and is subjected to image processing, thereby displaying an MR image. In a transmission system of an MRI apparatus shown in FIG. 1, an oscillator 51 generates a high-frequency signal having a frequency corresponding to the Lamor frequency of a nuclide of interest. A modulator 52 modulates the high-frequency signal output from the oscillator 51 by using a modulation signal based on a pulse sequence. An amplifier 53 amplifies the high-frequency signal modulated by the modulator 52 up to about 1 to 15 kW. The amplified high-frequency signal is applied as an RF pulse by an RF coil 54 to a subject to be examined. In the transmission system having the above-described arrangement, the slice profile of an MR slice image is determined by the input/output characteristics of the amplifier 53. Input and output signals to/from the amplifier 53 may exhibit waveforms shown in, e.g., FIG. 2 depending on a variation in components of the amplifier 53. In FIG. 2, reference symbol IN denotes an input signal; and OUT, an output signal. That is, as shown in FIG. 3, although a linear input/output characteristic curve S L is preferably obtained, a nonlinear input/output characteristic curve S N is obtained in practice. A general amplifier can perform substantially linear amplification with a predetermined amplification factor when an input signal has a low level. However, when an input signal has a high level, since the amplification factor is decreased, linear amplification cannot be performed. In a conventional MRI apparatus, however, proper countermeasures against a nonlinear amplification or occurrence of distortion of an output signal in a high-frequency amplifier have not been taken. When an RF pulse is generated by supplying a distorted current to an RF coil, the RF pulse excites not only a nuclide of interest in a selective excitation portion in a subject to be examined but also nuclides in other portions. Since signals from other portions are thus included in a detected MR signal, an MR image having high resolution cannot be reconstructed. FIG. 4A shows the spectrum distribution of an RF pulse obtained by ideal linear amplification using a high-frequency amplifier. In FIG. 4A, a spectrum width Δω corresponds to the thickness of a portion to be excited. If linear amplification is not performed in a high-frequency amplifier, the spectrum of an obtained RF pulse exhibits a spectrum distribution shown in, e.g., FIG. 4B. As described, therefore, in this case, not only a selected excitation portion of a subject to be examined but also an adjacent portion are excited. For this reason, in a multi-slice operation, gaps are generated between the respective slices. A strong demand, therefore, has arisen for an MRI apparatus having a high-frequency amplifier capable of generating an RF pulse without distortion. SUMMARY OF THE INVENTION It is an object of the present invention to provide a method of controlling an RF pulse in an MRI apparatus and a system for practicing the method. According to one aspect of the present invention, there is provided a system for controlling an RF pulse applied to a subject in a magnetic resonance imaging apparatus, the system comprising: generating means for generating an RF signal having a frequency corresponding to a resonance frequency of a nucleus within the subject in a magnetic field; modulating means for modulating the generated RF signal to generate an RF pulse having a predetermined frequency spectrum for slicing a portion of the subject; amplifying means for amplifying the modulated RF signal; detecting means for detecting the amplified RF signal; and controlling means for controlling an amplification factor of the amplifying means in accordance with the detected RF signal and the generated RF signal to linearly amplify the modulated RF signal. According to another aspect of the present invention, there is provided a method for controlling an RF pulse applied to a subject in a magnetic resonance imaging apparatus, the method comprising the steps of: generating an RF signal having a frequency corresponding to a resonance frequency of a nucleus within a subject in a magnetic field; modulating the generated RF signal to generate an RF pulse having a predetermined frequency spectrum for slicing a portion of the subject; amplifying the modulated RF signal; detecting the amplified RF signal; and controlling an amplification factor in accordance with the detected RF signal and the generated RF signal to linearly amplify the modulated RF signal. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an arrangement of a conventional transmission system; FIG. 2 shows waveforms of input and output signals in an amplifier; FIG. 3 is a graph showing input/output characteristics of the amplifier; FIGS. 4A and 4B show spectrum distributions of RF pulses for linear amplification and nonlinear amplification in the amplifier; FIG. 5 is a block diagram showing an arrangement of an MRI system according to a first embodiment of the present invention; FIG. 6 shows output signal waveforms in the respective sections of a transmission system in FIG. 5; FIG. 7 is a block diagram showing an arrangement of a system according to a second embodiment of the present invention; FIG. 8 is a block diagram showing a circuit arrangement of a high-frequency amplifier and a differential amplifier in the system shown in FIG. 7; and FIG. 9 is a block diagram showing an arrangement of a system according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings. Referring to FIG. 5, a system according to a first embodiment comprises a static field coil 10 for generating a static field Ho, coils 11, 12, and 13 for respectively generating X-, Y-, and Z-axis gradient fields Gx, Gy, and Gz, an RF coil 4 for transmitting an RF pulse and detecting an MR signal from a subject P, a static field power supply 14 for supplying a current to the static field coil 10, gradient field power supplies 15, 16, and 17 for respectively supplying currents to the gradient field coils 11, 12, and 13, a receiver 18, a sequence controller 19 for executing a pulse sequence, a computer system 20 for performing image processing based on an MR signal and performing a display or the like of the processing result, and a transmission system 45. The transmission system 45 comprises a high-frequency amplifier 1, a modulator 2, an oscillator 3, a current detector 5, a demodulator 6, and a differential amplifier 9. The oscillator 3 generates a high-frequency signal having a frequency corresponding to the Lamor frequency of an atomic nucleus to be excited. When, for example, proton imaging is to be performed in a static field Ho having an intensity of 0.5 T (tesla), a high-frequency signal of 21.3 MHz is generated. The modulator 2 modulates the high-frequency signal from the oscillator 3 in accordance with a modulation signal from the differential amplifier 9. The modulated high-frequency signal has a predetermined spectrum distribution for selective excitation. The high-frequency amplifier 1 amplifies the modulated high-frequency signal. The amplified high-frequency signal is applied as an RF pulse from the RF coil 4 to the subject P. The current detector 5 constituted by a current transformer or the like detects the signal amplified by the high-frequency amplifier 1. The demodulator 6 demodulates the signal detected by the current detector 5. The differential amplifier 9 obtains the difference between the signal demodulated by the demodulator 6 and a modulation signal from the sequence controller 19, and outputs a modulation signal based on the difference to the modulator 2. An operation of the system according to the first embodiment will be described below. As shown in FIG. 5, the subject P is placed in the static field Ho, and the transmission system 45 is driven in accordance with a pulse sequence by the sequence controller 19. In the transmission system 45, a high-frequency signal from the oscillator 3 is modulated by the modulator 2 in accordance with a modulation signal from the differential amplifier 9, and is amplified by the high-frequency amplifier 1. Thereafter, the amplified signal is applied as an RF pulse from the RF coil 4 to the subject P. Note that waveforms A to E shown in FIG. 6 respectively correspond to outputs from the oscillator 3, the differential amplifier 9, the modulator 2, the high-frequency amplifier 1, and the demodulator 6. When the gradient field power supplies 15, 16, and 17 are driven in accordance with a pulse sequence by the sequence controller 19, slicing, phase encoding, and read gradient fields are respectively applied from the gradient fields coils 11, 12, and 13 to the subject P. Consequently, an MR phenomenon occurs, and an MR signal from the subject P is detected by the RF coil 4. The computer system 20 performs image reconstruction processing based on the detected MR signal and displays an MR image or the like. Since the transmission system 45 is operated to compensate for the input/output characteristics of the high-frequency amplifier 1, and RF pulse having no distortion can be generated, and an MR image with high resolution can be obtained. FIG. 7 shows an arrangement of a system according to a second embodiment of the present invention. This system is different from the system of the first embodiment shown in FIG. 5 in that an output signal from a differential amplifier 8 of a transmission system 45a is input to a high-frequency amplifier 41. Note that the transmission system 45a comprises a comparator 7. Referring to FIG. 7, the comparator 7 compares a signal output from a demodulator 6 with a modulation signal output from a sequence controller 19, and generates a differential signal representing the difference between the signals. The differential signal generated by the comparator 7 is amplified by the differential amplifier 8 and is output to the high-frequency amplifier 41. FIG. 8 shows a circuit arrangement of the high-frequency amplifier 41 and the differential amplifier 8 shown in FIG. 7. The amplifier 41 comprises power amplifying FETs Q1 and Q2, an input matching circuit 31, and an output matching circuit 33. The amplifier 8 comprises a transistor Q3 and operational amplifiers X1 and X2. An output signal from the modulator 2 is supplied to the input matching circuit 31 to perform matching of an input impedance. An output signal from the input matching circuit 31 is supplied through a CR circuit to a push-pull power amplifying circuit constituted by the FETs Q1 and Q2. The biases of the FETs Q1 and Q2 are controlled by an output signal from the differential amplifier 8, as will be described later. The output signal from the comparator 7 is amplified by the operational amplifier X2 and is divided by a variable resistor R1. Thereafter, the divided signal is supplied to a constant current circuit constituted by the operational amplifier X1. Note that an output current from the operational amplifier X1 represents the magnitude of distortion in the high-frequency amplifier 41 and is proportional to a voltage divided by the variable resistor R1. A signal obtained by superposing the output signal from the input matching circuit 31 on a bias signal (voltage) corresponding to the output current from the operational amplifier X1 is supplied to the gate of each of the FETs Q1 and Q2. In this case, the absolute value of an output signal obtained by ideal linear amplification is subtracted from the absolute value of an actual output signal from the high-frequency amplifier 41. A bias voltage having the polarity corresponding to the sign of the obtained difference is applied to the gate of each of the FETs Q1 and Q2. For example, if the sign of the subtraction value is negative, i.e., the distortion is negative, a bias voltage having a polarity for reducing the biases of the FETs Q1 and Q2 is applied to the gates of the FETs Q1 and Q2. As a result, the amplification factors of the FETs Q1 and Q2 are increased to reduce the distortion. By adjusting the biases of FETs Q1 and Q2 constituting the power amplifying circuit, the amplification factors can be changed. Since the distortion can be reduced with this adjustment, linear amplification can be performed regardless of the level of a signal input to the high-frequency amplifier 41. Bias adjustment in the high-frequency amplifier 41 is performed by on/off-controlling the transistor Q3 by using a pulse signal output from the sequence controller 19 in synchronism with an RF signal input to the input matching circuit 31. This pulse signal has a pulse width corresponding to that of the RF signal and is input to the base of the transistor Q3. When no RF signal is input to the input matching circuit 31, the transistor Q3 is set in an on state, and a bias voltage to the FETs Q1 and Q2 becomes zero. Therefore, unnecessary power losses in the FETs Q1 and Q2 can be prevented, and moreover, superposition of noise on an RF pulse can be prevented. When an RF signal is input to the input matching circuit 31, the transistor Q3 is set in an off state, and bias adjustment for the FETs Q1 and Q2 is performed. FIG. 9 shows an arrangement of a system according to a third embodiment of the present invention. This system is different from the system of the second embodiment shown in FIG. 7 in that a transmission system 45b comprises a current detector 5a for detecting a signal input to a high-frequency amplifier 41 and a demodulator 6a for demodulating the signal detected by the current detector 5a. An output signal from the demodulator 6a is supplied to a comparator 7 to be compared with an output signal from a demodulator 6. Linear amplification without distortion can be also performed by such an arrangement. As has been described above, the high-frequency amplifiers in the transmission systems of the embodiments can perform linear amplification without distortion regardless of the level of an RF signal. An RF pulse generated by the RF coil using an amplified RF signal has a spectrum distribution representing a predetermined intensity in a predetermined frequency domain and a zero intensity in other frequency domains. When a nuclide of interest in a subject to be examined is selectively excited by such an RF signal, the boundary between a portion including the nuclide to be excited and a portion including a nuclide not to be excited becomes distinctive. If the RF pulse is a 90 degree pulse, the macroscopic direction of magnetization in a portion to be excited is accurately inclined at 90 degrees with respect to the direction of the static field. Therefore, if image reconstruction processing is performed on the basis of an MR signal detected by applying such an RF pulse to a subject to be examined, an MR image having high resolution can be obtained. The embodiments of the present invention have been described so far. However, the present invention is not limited to the above-described embodiments. Various changes and modifications can be made within the spirit and scope of the invention.

In an MRI apparatus, the amplification factor of a high-frequency amplifier incorporated in the transmission system for generating RF pulses is automatically controlled in accordance with the input/output characteristic between the signal input to the amplifier and the signal output therefrom. Hence, the amplifier can perform a linear amplification of the input signal, regardless of the level of the input signal. Hence, the transmission system can generate RF pulses having a spectral distribution representing a predetermined intensity in only a specified frequency domain, using the signal output from the amplifiers.

CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY CLAIM This application is a continuation of U.S. Non-Provisional application Ser. No. 13/228,491, entitled “EMBEDDING A NANOTUBE INSIDE A NANOPORE FOR DNA TRANSLOCATION”, filed Sep. 9, 2011, which is incorporated herein by reference in its entirety. BACKGROUND Exemplary embodiments relate to nanodevices, and more specifically, to providing a smooth inner surface for a nanopore by fixing a nanotube inside the nanopore. Recently, there has been growing interest in applying nanopores as sensors for rapid analysis of biomolecules (e.g., polymers) such as deoxyribonucleic acid (DNA), ribonucleic acid (RNA), protein, etc. Emphasis has been given to applications of nanopores for DNA sequencing, as this technology holds the promise to reduce the cost of sequencing below $1000/human genome. Nanopore sequencing is a technique for determining the order in which nucleotides occur on a strand of DNA. A nanopore is simply a small hole of the order of several nanometers in internal diameter. The theory behind nanopore sequencing has to do with what occurs when the nanopore is immersed in a conducting fluid and an electric potential (voltage) is applied across it: under these conditions, a slight electric current due to conduction of ions through the nanopore can be measured, and the amount of current is very sensitive to the size and shape of the nanopore. If single bases or strands of DNA pass (or part of the DNA molecule passes) through the nanopore, this can create a change in the magnitude of the current through the nanopore. Other electrical or optical sensors can also be put around the nanopore so that DNA bases can be differentiated while the DNA passes through the nanopore. BRIEF SUMMARY According to an exemplary embodiment, a method of embedding a nanotube in a nanopore is provided. The method includes configuring a reservoir including a membrane separating the reservoir into a first reservoir part and a second reservoir part, where the nanopore is formed through the membrane for connecting the first and second reservoir parts. The method includes filling the nanopore, the first reservoir part, and the second reservoir part with an ionic fluid, where a first electrode is dipped in the first reservoir part and a second electrode is dipped in the second reservoir part. Also, the method includes driving the nanotube into the nanopore using a voltage bias being applied to the first and second electrodes, to cause an inner surface of the nanopore to form a covalent bond to an outer surface of the nanotube via an organic coating. Additional features are realized through the techniques of the present disclosure. Other systems, methods, apparatus, and/or computer program products according to other embodiments are described in detail herein and are considered a part of the claimed invention. For a better understanding of exemplary embodiments and features, refer to the description and to the drawings. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features of the present disclosure are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: FIG. 1 depicts a cross-sectional schematic of a nanodevice with a nanopore embedded with a carbon nanotube according to an exemplary embodiment. FIG. 2A illustrates an approach to embed a carbon nanotube inside a nanopore of a nanodevice according to an exemplary embodiment. FIG. 2B illustrates the carbon nanotube attached/bonded to the inside of the nanopore according to an exemplary embodiment. FIG. 2C illustrates the carbon nanotube attached to the inside of the nanopore after processing according to an exemplary embodiment. FIG. 3A illustrates another approach to embed a carbon nanotube inside a nanopore of a nanodevice according to an exemplary embodiment. FIG. 3B illustrates the carbon nanotube attached/bonded to the inside of the nanopore according to an exemplary embodiment. FIG. 3C illustrates the carbon nanotube attached to the inside of the nanopore after processing according to an exemplary embodiment. FIG. 4A illustrates an additional approach to embed a carbon nanotube inside a nanopore of a nanodevice according to an exemplary embodiment. FIG. 4B illustrates the carbon nanotube attached/bonded to the inside of the nanopore according to an exemplary embodiment. FIG. 4C illustrates the carbon nanotube attached to the inside of the nanopore after processing according to an exemplary embodiment. FIG. 5 is a method for embedding a nanotube inside a nanopore according to an exemplary embodiment. DETAILED DESCRIPTION An issue in DNA sequencing is to control the translocation of the DNA through the nanopore. The surface roughness of the nanopore and the dangling bonds on the surface of the nanopore may present problems for DNA sequencing. After drilling a solid-state nanopore using an electron beam, the pore surface may exhibit nanometer scale corrugations (e.g., folds, wrinkles, groves, etc.). Similar to the scaling behavior of a self-affine rough surface, the smaller a nanopore is the rougher the inner pore surface is. Additionally, nanopores drilled using the same procedure may have different surface roughness, causing each pore to be unique. Thus, experiments that are performed using nanopores with rough surfaces and/or dangling bonds may likely (or may possibly) show inconsistent results because of the unpredictable interactions between DNA and the inner surface of the nanopore. For example, simulations show that the effective electric driving forces on DNA are different if the surface roughness of the same-sized nanopores is different. Exemplary embodiments are configured to attach carbon nanotubes at the inner surface of the nanopore and leverage the smoothness of the inner surface of carbon nanotubes. This approach can eliminate the physical surface roughness as well as the dangling bonds at the inner surface of the nanopore, which are the sources of unpredictable interactions between DNA and the inner surface of the nanopore. Additionally, the chemical inertness of carbon nanotubes will be a potential benefit, such as by protecting the metal electrodes employed at the inner surface of the nanopore. Now turning to the figures, FIG. 1 depicts a cross-sectional schematic of a nanodevice 100 with a nanopore embedded with a carbon nanotube according to an exemplary embodiment. The nanodevice 100 illustrates a DNA translocation setup. A membrane 150 is made of one or more insulating films 101 with a nanopore 103 formed through the insulating film 101 . A carbon nanotube 102 is embedded at the inner surface of the nanopore 103 . The insulating film 101 of the membrane 150 partitions a reservoir 104 into two reservoir parts, which are reservoir part 105 and reservoir part 106 . The reservoir 104 (including reservoir parts 105 and 106 ) and the nanopore 103 are then filled with ionic buffer/fluid 107 (e.g., such as a conductive fluid). A polymer 108 such as a DNA molecule(s) is loaded into the nanopore 103 by an electrical voltage bias of the voltage source 109 , which is applied across the nanopore 103 via two electrochemical electrodes 110 and 111 . The electrodes 110 and 111 are respectively dipped in the ionic buffer 107 of the reservoir part 105 and the reservoir part 106 in the reservoir 104 . There are various state of the art techniques for sensing DNA bases and controlling the motion of the DNA, and the roughness and the dangling bonds in a regular (state of the art) nanopore may pose a potential problem. However, the smooth inner surface of the nanotube 102 will provide a (very) smooth surface with no dangling bonds for characterization (i.e., nanopore sequencing of the DNA) and movement of the polymer 108 . There may be many techniques with many different materials that can be utilized to make the nanodevice 100 shown in FIG. 1 . According to an exemplary embodiment, FIGS. 2A , 2 B, and 2 C illustrate one approach to embed a carbon nanotube inside a nanopore of a nanodevice 200 such as a chip. FIGS. 2A , 2 B, and 2 C depict a cross-sectional schematic of the nanodevice 200 . In FIG. 2A , a membrane 250 includes a substrate 201 (e.g., such as silicon), between membrane parts 202 and 203 . The membrane parts 202 and 203 may be made of a material (such as Si 3 N 4 (silicon nitride)) with a high etching selectivity with respect to the substrate 201 . The membrane part 202 may also contain other material layers, such as metal layers, etc., for any desired application. A window 255 is opened into the membrane part 203 using, e.g., reactive ion etching, and the substrate 201 will be etched through to the membrane part 202 ; etching through the window 255 of the membrane part 203 as well as through the substrate 201 will form a free-standing membrane part 260 of the membrane part 202 . In the case of a silicon substrate for the substrate 201 , the etchant could be KOH (potassium hydroxide) or TMAH (tetramethylammonium hydroxide) at 80° C. A nanopore 207 is made/formed through the free-standing membrane part 260 of the membrane part 202 . The membrane 250 (including the free-standing membrane part 260 ) partitions a reservoir 208 into reservoir part 209 and reservoir part 210 . The reservoir 208 (including reservoir parts 209 and 210 ) and the nanopore 207 formed through membrane part 202 are (then) filled with ionic buffer/fluid 211 . The nanopore 207 is a small aperture formed in, e.g., the free-standing membrane part 260 of the membrane part 202 . As shown in FIG. 2A , the outer surface of a carbon nanotube 204 can be coated with an organic coating 205 . The organic coating 205 is configured to be covalently bonded to the inner surface of the nanopore 207 . The organic coating 205 and/or the carbon nanotube 204 is charged (by tuning the pH of the ionic buffer 211 ), such that the carbon nanotube 204 can be transported/driven into the nanopore 207 by the voltage source 109 applying a voltage bias to electrodes 110 and 111 , and then the carbon nanotube 204 can be covalently bonded to the inner surface of the nanopore 207 , as shown in FIG. 2B . Alternatively and/or additionally, a fluidic pressure adjustment device 280 can be communicatively connected to the reservoir part 210 via a port 282 , and a fluidic pressure adjustment device 285 can be communicatively connected to the reservoir part 209 via another port 284 in one implementation. To drive the carbon nanotube 204 (which can be charged or uncharged) into the nanopore 207 , the fluidic pressure adjustment device 280 is configured to apply a positive fluidic pressure to the reservoir part 210 and/or the fluidic pressure adjustment device 285 is configured to apply a negative fluidic pressure to the reservoir part 209 . The carbon nanotube 204 is driven into the nanopore 207 by the difference in fluidic pressure on both sides of the membrane 250 caused by fluidic pressure adjustment device 280 and 285 . Also, the carbon nanotube 204 can be driven into the nanopore 207 by the positive fluidic pressure of the fluidic pressure adjustment device 280 alone or by the negative fluidic pressure of the fluidic pressure adjustment device 285 alone. The fluidic pressure adjustment devices 280 and 285 may be pumps or syringes respectively linked via ports 282 and 284 to the reservoir parts 210 and 209 to apply the desired pressure. The ionic buffer 107 and 211 in the reservoirs 104 and 208 can be any salt dissolved in any solvent (water or organic solvent) with any pH depending on the application. One example of the ionic buffer 107 and 211 includes a KCl (potassium chloride) solution in water with a pH range from 6-9 for DNA translocation. Accordingly, the electrodes 110 and 111 can be any electrodes for electrochemical reactions that match the salt and solvent. For example, Ag/AgCl electrodes can be a good match for the KCl solution in water. As discussed further below, the organic coating 205 is a material having chemical properties that cause the organic coating 205 (applied to the carbon nanotube 204 ) to covalently bond to the inner surface material of the nanopore 207 . As a result of the covalent bond, the carbon nanotube 204 is securely attached to the nanopore 207 . Once the carbon nanotube 204 is attached to the inner surface of nanopore 207 , both sides (e.g., top and bottom) of the membrane 250 (including the attached nanotube 204 ) can be processed/etched with O 2 (oxygen) plasma to tailor (e.g., remove) the parts of the carbon nanotube 204 that are extending outside of the nanopore 207 , as shown in FIG. 2C . In FIG. 2C , the height of the carbon nanotube 204 (e.g., the top and bottom) is aligned with the height of the membrane part 202 after the O 2 plasma processing. The polymer 108 (shown in FIG. 1 ) may be driven into the carbon nanotube 204 attached to the nanopore 207 for sequencing by a nanopore sequencer (not shown), and the sequencing occurs in the nanopore 207 (formed by the carbon nanotube 204 ) as understood by one skilled in the art. Oxygen plasma etching is a form of plasma processing used to fabricate integrated circuits. As understood by one skilled in the art, it involves a high-speed stream of glow discharge (plasma) of an appropriate gas mixture being shot (in pulses) at a sample, such as at the membrane 250 . Although plasma etching is described, it is contemplated that other types of etching may be utilized as understood by one skilled in the art. FIGS. 3A , 3 B, and 3 C illustrate another approach to embed a carbon nanotube inside a nanopore according to an exemplary embodiment. FIGS. 3A , 3 B, and 3 C depict a cross-sectional schematic of the nanodevice 300 . In FIGS. 3A , 3 B, and 3 C, the inner surface of the nanopore 207 is coated with the organic coating 215 , which can bond to the carbon nanotube 204 . The description for FIGS. 3A , 3 B, and 3 C are the same as for FIGS. 2A , 2 B, and 2 C, except that the carbon nanotube 204 is initially uncoated because the coating is applied to the inner surface of the nanopore 207 , instead of on the carbon nanotube 204 (itself). The organic coating 215 in FIGS. 3A , 3 B, and 3 C may be the same material as the organic coating 205 in FIGS. 2A , 2 B, and 2 C in one implementation, and may be different materials in another implementation. In FIG. 3A , the membrane 250 includes the substrate 201 , between membrane parts 202 and 203 , and window 255 is opened/etched into the membrane part 203 through the substrate 201 to the membrane part 202 to form the free-standing membrane part 260 of the membrane part 202 , as discussed above. The nanopore 207 is made/formed through the free-standing membrane part 260 . The membrane 250 (including the free-standing membrane part 260 ) partitions a reservoir 208 into reservoir part 209 and reservoir part 210 . The reservoir 208 (including reservoir parts 209 and 210 ) and the nanopore 207 formed through membrane part 202 are then filled with ionic buffer/fluid 211 as discussed above. Unlike FIG. 2A , the outer surface of the carbon nanotube 204 is not coated with the organic coating 205 in FIG. 3A . Instead, the inner surface of the nanopore 207 is coated with the organic coating 215 . The organic coating 215 is configured to covalently bond to the outer surface of the uncoated carbon nanotube 204 . If the carbon nanotube 204 is charged (by tuning the pH of the ionic buffer 211 filling the reservoir 208 ), the carbon nanotube 204 can be transported into the nanopore 207 by a voltage bias applied to electrodes 110 and 110 via the voltage source 109 . Also, the carbon nanotube 204 can be driven into the nanopore 207 by the difference in fluidic pressure on both sides of the membrane 250 applied by positive and negative pressures of the fluidic pressure adjustment devices 280 and 285 . Once the carbon nanotube 204 is driven into the nanopore 207 , the carbon nanotube 204 can be covalently bonded to the inner surface of the nanopore 207 via the organic coating 215 , as shown in FIG. 3B . The organic coating 215 is a material having chemical properties that cause the organic coating 215 (applied to the nanopore 207 ) to covalently bond to the outer surface material of the uncoated carbon nanotube 204 . As a result of this covalent bond, the carbon nanotube 204 is securely attached to the nanopore 207 . Once the carbon nanotube 204 is attached to the inner surface of nanopore 207 , both sides of the membrane 250 (including the attached nanotube 204 ) can be processed with O 2 plasma to tailor (e.g., remove) the extending parts of the carbon nanotube 204 that extend outside of the nanopore 207 , as shown in FIG. 3C . In FIG. 3C , the height of the carbon nanotube 204 is aligned to the height of the membrane part 202 after O 2 plasma processing. The polymer 108 (shown in FIG. 1 ) may be driven into the carbon nanotube 204 attached to the nanopore 207 for sequencing as understood by one skilled in the art. FIGS. 4A , 4 B, and 4 C illustrate an additional approach to embed a carbon nanotube inside a nanopore according to an exemplary embodiment. FIGS. 4A , 4 B, and 4 C depict a cross-sectional schematic of the nanodevice 400 which illustrates a combination of the approaches discussed in FIGS. 2A , 2 B, 2 C, 3 A, 3 B, and 3 C. In FIGS. 4A , 4 B, and 4 C, the inner surface of the nanopore 207 is coated with an organic coating 206 , while the outer surface of the carbon nanotube 204 is coated with the organic coating 205 . The organic coating 205 is chemically configured to covalently bond to the organic coating 206 . Additionally, the organic coating 205 is chemically configured to bond to the carbon nanotube 204 , and the organic coating 206 is chemically configured to bond to the inner surface of the nanopore 207 . The organic coating 205 is different from the organic coating 206 in one implementation. In another implementation, the organic coating 205 can be the same material as the organic coating 206 . When the organic coating 205 and/or carbon nanotube 204 is charged (by tuning the pH of the ionic buffer), the carbon nanotube 204 can be transported into the nanopore 207 by a voltage bias applied to electrodes 110 and 110 via the voltage source 109 . Also, the carbon nanotube 204 can be driven into the nanopore 207 by the difference in fluidic pressure on both sides of the membrane 250 applied by the positive and negative pressures of the fluidic pressure adjustment devices 280 and 285 . Once the carbon nanotube 204 coated in the organic coating 205 is driven into the nanopore 207 coated in the organic coating 206 , the carbon nanotube 204 can be covalently bonded to the inner surface of the nanopore 207 via the organic coatings 205 206 , as shown in FIG. 4B . The organic coating 205 is a material having chemical properties that cause the organic coating 205 (applied to the carbon nanotube 204 ) to covalently bond to the outer surface material of the carbon nanotube 204 and to the organic coating 206 . Similarly, the organic coating 206 is a material having chemical properties that cause the organic coating 206 (applied to the nanopore 207 ) to covalently bond to the outer surface material of the carbon nanotube 204 and to the organic coating 205 . As a result of the covalent bonding, the carbon nanotube 204 is securely attached to the nanopore 207 . As mentioned above, once the carbon nanotube 204 is attached to the inner surface of nanopore 207 , both sides of the membrane 250 (including the attached nanotube 204 ) can be processed with O 2 plasma to tailor (e.g., remove) the extending parts of the carbon nanotube 204 that extend outside of the nanopore 207 , as shown in FIG. 4C . In FIG. 4C , the height of the carbon nanotube 204 is aligned to the height of the membrane part 202 after O 2 plasma processing. In one implementation, the height of the carbon nanotube 204 may be slightly less than, more than, or about the same as the height of the membrane part 202 (forming the nanopore 207 ) based on the desired precision of the O 2 plasma processing. The polymer 108 (shown in FIG. 1 ) may be driven into the carbon nanotube 204 attached to the nanopore 207 for sequencing as understood by one skilled in the art. Although exemplary embodiments described above may be directed to carbon nanotubes, it should be appreciated that the disclosure is not restricted to nanopores with carbon nanotubes. Rather, exemplary embodiments may be applicable for attaching other types of nanotubes to the inside surface of nanopores utilizing the techniques as discussed herein. Additionally, exemplary embodiments are not limited to embedding nanotubes into nanopores, and nanotubes may be embedded into other structures such as vias, nanochannels, etc., as understood by one skilled in the art. FIG. 5 illustrates a method 500 for embedding a nanotube in a nanopore in accordance with an exemplary embodiment. Reference can be made to FIGS. 1 , 2 A, 2 B, 2 C, 3 A, 3 B, 3 C, 4 A, 4 B, and 4 C. A reservoir (e.g., reservoir 104 , 208 ) is configured to include a membrane (e.g., membrane 150 , 250 ) separating the reservoir into a first reservoir part (e.g., reservoir part 105 , 210 ) and a second reservoir part (e.g., reservoir part 106 , 209 ) in which the nanopore (e.g., nanopore 103 , 207 ) is formed through the membrane for connecting the first and second reservoir parts at block 505 . The nanopore, the first reservoir part, and the second reservoir part are filled with an ionic fluid (e.g., ionic fluid 107 , 211 ) at block 510 . A first electrode (e.g., electrode 110 ) is dipped in the first reservoir part at block 515 , and a second electrode (e.g., electrode 111 ) is dipped in the second reservoir part at block 520 . At block 525 , the nanotube is driven into the nanopore to cause an inner surface of the nanopore (e.g., nanopore 103 , 207 ) to form a covalent bond to an outer surface of the nanotube (e.g., nanotube 102 , 204 ) via an organic coating (e.g., organic coating 205 , 206 , 215 ), in response to a voltage bias being applied (e.g., by the voltage source 109 ) to the first and second electrodes (e.g., electrodes 110 and 111 ). Also, the carbon nanotube 204 can be driven into the nanopore 207 by the difference in fluidic pressure on both sides of the membrane 250 applied by the positive and negative pressures of the fluidic pressure adjustment devices 280 and 285 . The inner surface of the nanopore 207 may be coated with the organic coating (e.g., organic coating 215 in FIG. 3A or organic coating 206 in FIG. 4A ) to form the covalent bond to the outer surface of the nanotube 204 . Also, the outer surface of the nanotube 204 may be coated with the organic coating 205 to form the covalent bond to the inner surface of the nanopore 207 . In one case, both the inner surface of the nanopore 207 and the outer surface of the nanotube 204 are coated with the organic coating (e.g., the organic coatings 205 and 206 may be the same material in FIGS. 4A , 4 B, and 4 C), such that the organic coating on the inner surface of the nanopore 207 and the organic coating on the outer surface of the nanotube 204 cause the covalent bond in response to the voltage source 109 driving the nanotube 204 into the nanopore 207 . In another case, the inner surface of the nanopore 207 is coated with the organic coating and the outer surface of the nanotube is coated with another organic coating (e.g., the organic coatings 205 and 206 may be different materials in FIGS. 4A , 4 B, and 4 C), such that the organic coating on the inner surface of the nanopore and the other organic coating on the outer surface of the nanotube cause the covalent bond in response to the voltage source 109 driving the nanotube into the nanopore. The covalent bond via the organic coating causes the nanotube 102 , 204 to be physically attached to the nanopore 103 , 207 formed in the membrane 150 , 250 , and both sides (e.g., top and bottom) of the membrane 150 , 250 are processed such that a height of the nanotube corresponds to a height of a layer (e.g., membrane part 202 ) of the membrane 250 as shown in FIGS. 2C , 3 C, and 4 C. For explanatory purposes, various examples of the organic coatings 205 , 206 , and 215 are discussed below. It is understood that the chemical molecules of the organic coatings 205 , 206 , and 215 discussed below are not meant to be limited. The organic coating 205 can be prepared by reaction of aryldiazonium salts with the carbon nanotube 204 . In this reaction, the diazonium salts are reduced by electron transfer from the carbon nanotube 204 to diazonium salts and results in the expulsion of one molecule of nitrogen and formation of a carbon-carbon bond between aryl compound and the carbon nanotube 204 . This is a widely used reaction for functionalization of carbon nanotubes with a variety of aryl compounds mainly because of the simplicity of the reaction and the wide range of arydiazonium salts available through their corresponding arylamines. The reaction of aryldiazonium salts with the carbon nanotube 204 takes place either in aqueous solution or an organic solvent like dichloroethane, chloroform, toluene, dimethylformamide, etc. The reaction of aryldiazonium salts with the carbon nanotube 204 is very fast (e.g., completed within a few minutes) and takes place at room temperature. The preferred, but not required, diazonium salts are those with an additional functionality which can form strong bonds with metal oxides or nitrides inside the nanopore 207 . The additional functionality (to form strong bonds with metal oxides or nitrides inside the nanopore 207 ) can be chosen from carboxylic acids (—CO 2 H), hydroxamic acids (—CONHOH), or phosphonic acids (—PO 3 H 2 ). In FIGS. 3A , 3 B, and 3 C, the organic coating 215 is a bifunctional compound/molecule in which one functionality is a diazonium salt and the other functionality can be chosen from hydroxamic acid or phosphonic acid. When the nanopore 207 with inside walls of metal oxide or metal nitride is immersed in a solution of this bifunctional compound/molecule, the inner surface of the nanopore 207 is coated with the self-assembled monolayer of this bifunctional compound/molecule through hydroxamic acid or phosphonic acid functionality and exposes the diazonium functional group; the diazonium functional group can react with the uncoated carbon nanotube 204 (as shown in FIGS. 3B and 3C ) to form a covalent bond, therefore immobilizing the carbon nanotube 204 inside the nanopore 207 . In FIGS. 4A , 4 B, and 4 C, both the carbon nanotube 204 and nanopore 207 are coated with organic monolayers (i.e., organic coatings 205 and 206 respectively). In the case of the carbon nanotube 204 , the organic coating 205 is achieved by reaction of the carbon nanotube 204 with bifunctional diazonium salts which have either alcohol or amine groups, and the organic coating 206 inside the nanopore 207 is a bifunctional molecule having a functional group which forms a bond inside the nanopore 207 wall (e.g., hydroxamic acid or phosphonic acid) and the second exposed functionality which forms a covalent bond through condensation with exposed functionality of the carbon nanotube 204 (e.g. carboxylic acid). For example, the nanopore 207 can be coated with 4-carboxybenzylphosphonic acid by immersion of the nanopore 207 in a dilute (1-5 mmolar) solution of the latter in water or alcohol. After rinsing with the same solvent, the inside of the nanopore 207 (the wall or portion of the nanopore wall must be of metal oxide or nitride) is coated with a self assembled monolayer of 4-carboxybenzylphosphonic acid in a way that phosphonic acid forms covalent bonds with metal oxide or nitride and exposes the carboxylic acid functionality. In the second step, the functionalized carbon nanotube 204 having an alcohol or amine functionality is pulled inside the nanopore 207 and with the aid of a dehydrating agent (which must be present in the salt solution) the two functionalities of carboxylic acid and alcohol (or amine) undergo dehydration to form carboxylic ester (or carboxamide) resulting in immobilization of carbon nanotube 204 . An example of the dehydrating agent (which is also water soluble and can be used in this environment) is N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride. In FIGS. 4B and 4C , after the organic coating 205 and 206 react with each other to form an ester or amide, the joined coatings are designated as 270 . For the reaction (corresponding to FIGS. 2A , 2 B, and 2 C) when the nanopore 207 is uncoated and the carbon nanotube 204 is coated (with organic coating 205 as discussed above), the organic coating 205 is achieved by the reaction of a bifunctional aryldiazonium salt. For example, 4-aminobenzylphosphonic acid is treated with nitrosonium tetrafluoroborate to form corresponding diazonium salt. A solution of this diazonium salt is added to an aqueous dispersion of carbon nanotubes containing small (0.1-1%) amount of surfactant (e.g., sodium dodecylsulfate or sodium cholate). After stiffing at room temperature for 30 minutes, the carbon nanotube 204 is functionalized with benzylphsophonic acid. An aqueous solution of the functionalized carbon nanotube 204 obtained above containing 0.1% anionic surfactant is pulled into nanopore 207 (as shown in FIGS. 2A , 2 B, 2 C) where the phosphonic acid functionality reacts with the surface of metal oxide (or nitride) inside the nanopore 207 to form a covalent bond. For the reaction (corresponding to FIGS. 3A , 3 B, and 3 C) when the nanopore 207 is coated (with organic coating 215 ) and the carbon nanotube 204 is uncoated, the inside of the nanopore 207 is coated (organic coating 215 ) with bifunctional arylamine, e.g., 4-aminophenylhydroxamic acid by immersion of the nanopore 207 in a dilute (1-5 mmolar) solution of the amine in ethanol. After sometime (e.g., 1-24 hours, preferably 1-2 hours) the substrate (forming the nanopore 207 ) is removed and rinsed with ethanol. This step results in self assembly of 4-aminophenylhydroxamic acid on the inside wall of nanopore 207 by formation of covalent bonds through hydroxamic acid functionality with metal oxide (or nitride) of the nanopore 207 and exposing arylamine functionality. Next, the coated nanopore 207 is treated with a dilute solution of nitrosonium ion (e.g., a solution of nitrosonium tetrafluoroborate or dilute solution of sodium nitrite in dilute hydrochloric acid) resulting in transformation of the amine group to diazonium salt. In the last step, the uncoated carbon nanotube 204 in salt solution is pulled into the coated nanopore 207 which will react with diazonium functionality of the self assembled monolayer and form carbon-carbon bond to immobilize the carbon nanotube 204 inside the nanopore 207 . The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, element components, and/or groups thereof. The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated The flow diagrams depicted herein are just one example. There may be many variations to this diagram or the steps (or operations) described therein without departing from the spirit of the invention. For instance, the steps may be performed in a differing order or steps may be added, deleted or modified. All of these variations are considered a part of the claimed invention. While the exemplary embodiments of the invention have been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described.

A technique for embedding a nanotube in a nanopore is provided. A membrane separates a reservoir into a first reservoir part and a second reservoir part, and the nanopore is formed through the membrane for connecting the first and second reservoir parts. An ionic fluid fills the nanopore, the first reservoir part, and the second reservoir part. A first electrode is dipped in the first reservoir part, and a second electrode is dipped in the second reservoir part. Driving the nanotube into the nanopore causes an inner surface of the nanopore to form a covalent bond to an outer surface of the nanotube via an organic coating so that the inner surface of the nanotube will be the new nanopore with a super smooth surface for studying bio-molecules while they translocate through the nanotube.

BACKGROUND [0001] Sealing devices are well known in the hydrocarbon recovery industry due to their ubiquitous use pursuant to varied needs throughout the wellbore. There are also many different types of sealing devices, some of which allow for testing immediately after setting by pressuring up on the well system to ensure that the setting procedure was successful. This is clearly beneficial as there is an immediate confirmation of a successful job. This occurs before the operator leaves the job site to insure that the job went well and thus promotes customer satisfaction. [0002] While the above testing opportunity is the case for many kinds of sealing devices it is not so for all devices. Swellable devices cannot be tested because their initial actuation is a much longer-term program. More specifically, swellable materials that are used in the wellbore generally set over a time period of about two weeks. While setting time does vary (due to particular fluid concentration and chemistry and the temperature of the wellbore at the location of the set), it is always over time long enough that it would be decidedly uneconomical to maintain testing equipment at a site to test such a seal after it is expected to be fully set. [0003] Because swellable materials have other beneficial properties and are favored in the art, they are becoming more and more prevalent despite the fact that testing is not realistically plausible. SUMMARY [0004] A swellable setting confirmation arrangement comprising a mandrel; a swellable material supported by the mandrel; one or more sensory configurations at the swellable material. [0005] A method for confirming setting of a swellable material comprising: running a swellable material to a target location in a wellbore; swelling the swellable material for a period of time; measuring strain caused by the swelling of the swellable material with one or more sensory configurations. [0006] A method for installing a swellable material having a setting confirmation function in a wellbore comprising: Installing one or more sensory configurations in a wellbore; installing a swellable material radially adjacent the one or more sensory configurations. BRIEF DESCRIPTION OF THE DRAWINGS [0007] Referring now to the drawings wherein like elements are numbered alike in the several Figures: [0008] FIG. 1 is a schematic view of a first embodiment of a set verification arrangement for a swellable device; [0009] FIG. 1A is an alternate configuration showing the sensory configuration in a spaced helical pattern; [0010] FIG. 1B is an alternate configuration showing the sensory configuration in a non-spaced helical pattern; [0011] FIG. 2 is a schematic view of a second embodiment of a set verification arrangement for a swellable device; [0012] FIG. 3 is a schematic view of a third embodiment of a set verification arrangement for a swellable device; and [0013] FIG. 4 is a schematic view of a fourth embodiment of a set verification arrangement for a swellable device. DETAILED DESCRIPTION [0014] The above-described drawback to the use of swellable devices in the downhole environment is overcome through various embodiments and methods as disclosed herein. [0015] Referring to FIG. 1 , a first embodiment is illustrated schematically in quarter section. A swellable setting confirmation arrangement 10 comprises a mandrel 12 having a swellable material 14 disposed there around. In one iteration, the swellable material 14 is around the mandrel 12 for 360 degrees but it should be noted that it is not necessarily required that the swellable material 14 be so configured. It is possible in other embodiments for the material 14 to be something short of 360 degrees about the mandrel 12 for particular applications without effect on the arrangement disclosed herein. Between the mandrel 12 and the swellable material 14 is disposed one or more sensory configuration(s) 16 . The configuration may comprise one or more optic fibers, load cells, strain sensors, such as hall effect sensors, momentary switches, etc. that have the ability to sense a load placed thereon (on or off, a “dichotomous measurement”). In one embodiment, the sensor(s) not only sense the presence of a load but additionally quantifies that load as well. The foregoing sensory configurations can be configured to sense quantitatively by known methods. Such sensing includes but are not limited to mercury strain gauges, rubber strain gauges, piezo resistance strain gauges, silicon strain gauges, wheatstone bridges, intrinsic sensors, extrinsic sensors, electro mechanical sensors, electro optic sensors, etc. An optic fiber based sensory configuration is an example of a configuration capable of both. The one or more sensory configurations 16 may thus be a single optic fiber, a plurality of fibers, a bundle of fibers, etc. extending roughly longitudinally and generally parallel to the mandrel 12 , or extending helically about the mandrel 12 (with the helix ranging from tightly wrapped (see FIG. 1B ) such that there is no gap between adjacent wraps of the optic fiber(s) to loosely wrapped (see FIG. 1 A) so that gaps from small to large may exist between the adjacent wraps of optic fiber(s)depending upon resolution desired). Determination of the density of the sensory configuration is directly related to the resolution of the information desired to be obtained. The greater the resolution desired, the greater the density needed. It is to be understood that the helical illustration of FIG. 1 is equally applicable to the FIG. 2 and FIG. 3 embodiments by substituting the configuration 16 in those illustrations for the configurations 16 shown in FIGS. 1A and 1B . It is intended that the reader understand that the helical conditions shown are applicable to any of the embodiments of the invention. [0016] In other embodiments, the one or more sensory configurations 16 may be placed randomly between the swellable material 14 and mandrel 12 or may be placed in any desired pattern between material 14 and mandrel 12 . This includes a pattern that is affected by the use of a network of strain sensors in a net of electrical connection, etc. The pattern may itself be unrelated to any anticipated distribution of strain (in which case the distribution is likely to be uniform but is not required to be) or may be specifically placed with regard to anticipated strain distribution. In either case, the purpose of the one or more sensory configurations 16 is to sense strain placed thereon by the swelling of the swellable material 14 . [0017] When a swellable material is set in a wellbore the material 14 will exert pressure against the mandrel 12 and the structure against which it is set. Depending upon a number of factors including but not limited to the degree of swelling attained and the geometric shape of the structure in which the swellable device is being set, the strain experienced at various portions of the swellable material and thus the mandrel may be different. The swellable setting confirmation arrangement 10 provides information to this effect to an operator. As noted above, since the swellable material swells slowly in the wellbore, on the order of two weeks, there is no way to test the set of the swellable while the installation crew and equipment is still on site. This means that if the swellable did not attain a set that enables it to do its job, this will not necessarily be known and presumably, production will suffer. If a well operator knows that something was a miss, remedial action could be taken. Where the arrangement 10 merely shows existence or absence of strain enough information is provided that the operator knows the device must be pulled and a new one put in. Where however, the arrangement 10 also provides a quantification of the strain thereon, a much more resolute picture of the downhole environment can be gleaned. This enables an operator or swellable installation crew to determine more precisely what type, shape, style, etc. of swellable would be best suited to have the desired effect in the particular wellbore. This is possible because with a quantification of strain, the geometry in the wellbore is far better defined since areas of greater strain and areas of lesser strain will indicate washed out areas or out of round areas of the structure downhole in which the device is being set. [0018] In the embodiments discussed above, as the swellable material swells into contact with a structure in which it is being set, the material 14 itself exerts more and more pressure on the mandrel. Because the one or more sensory configurations 16 are located between the material 14 and the mandrel 12 , they are compressed there between and hence will register that condition either dichotomously or quantitatively depending upon application. [0019] In another embodiment illustrated in FIG. 2 , the one or more sensory configurations 16 are embedded in the swellable material 14 . The one or more sensory configurations are hence put into compression upon swelling of the swellable material 14 similarly to that of the embodiment of FIG. 1 but the compression profile is distinct in that the configurations 16 are not directly compressed against the mandrel 12 . While the magnitude of compression may be smaller in this embodiment, it is still easily measured dichotomously or quantitatively. Further, in this embodiment the one or more sensory configurations may be better environmentally protected for some applications. [0020] In yet another embodiment, referring to FIG. 3 , the one or more sensory configurations 16 are located on an outside surface 20 of the material 14 . In this embodiment, the configurations 16 are exposed to the wellbore and are more likely to experience damage but they also will be directly in contact with the surface against which the swellable material 14 is to be set. This will provide a very accurate indication of the surface irregularities of the structure in applications where such is useful. [0021] In yet another embodiment, referring to FIG. 4 , the one or more sensory configurations 16 (each of those disclosed above are possible) are separated from the swellable material 14 . In one iteration the separated sensory configurations are still mounted to the same mandrel so that they can be put in place in a single run whereas in another iteration, the sensory configurations 16 could be mounted to a separate string for run in separately from the swellable material 14 if dictated by a particular need. FIG. 4 schematically illustrates both concepts by including a break line 26 that is intended to signify alternatively length of the mandrel 12 or a separate mandrel run at a different time. In either of these iterations, the one or more sensory configurations 16 are mountable in the wellbore 22 via a deployment method such as expansion. One embodiment will use rings 28 and 30 on either end of the configurations 16 that are expandable and will anchor the configurations 16 to the wellbore 22 . The configurations 16 are thus affixed to the wellbore 22 where after the swellable material 14 is positioned inside of the configuration(s) 16 and allowed to swell in the normal course. Progress of the swellable material can be monitored, as can that of the foregoing embodiments through the one or more sensory configurations 16 . It is also to be noted that the components can be reversed such that the configurations 16 are placed at a radially inward position instead of outward with similar effects. [0022] While preferred embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation

A swellable setting confirmation arrangement comprising: a mandrel; a swellable material supported by the mandrel; one or more sensory configurations at the swellable material and a method for confirming setting of a swellable material and for installing a swellable material having a setting confirmation function.

BACKGROUND OF THE INVENTION This invention relates to the preparation of copolycarbonates prepared by the melt polymerization reaction of at least two dihydroxy aromatic compounds with one or more diaryl carbonates, at least one of the dihydroxy aromatic compounds being having a substantial degree of volatility and thus being difficult to incorporate into the product copolycarbonate by conventional methods. Polycarbonates have excellent impact resistance and other mechanical properties as well as excellent heat resistance and transparency. Polycarbonates are widely used in applications ranging from football helmets to automobile parts to transparent security windows. More recently, polycarbonates have also proven to be the material of choice for optical media applications such as optical discs, for example compact discs (CD) and digital versatile discs (DVD). Conventional polycarbonates are usually produced by (1) an interfacial polymerization, in which bisphenol A (BPA) is reacted directly with phosgene or (2) a melt polymerization process in which BPA is transesterified with a carbonic acid diester such as diphenyl carbonate (DPC). For many applications, there has been a need for materials possessing the fundamental characteristics of transparency and toughness inherent in BPA polycarbonate but possessing, in addition, certain improvements in physical properties relative those possessed by bisphenol A polycarbonate (BPA-PC), for example birefringence. For some applications improved chemical resistance relative to BPA polycarbonate is required, for example in certain medical and automotive applications. Copolycarbonates are materials frequently possessing the fundamental traits of BPA polycarbonate, transparency and toughness, but in certain instances also possessing improved performance characteristics for a given application relative to BPA polycarbonate. One example of such a copolycarbonate comprises repeat units derived from resorcinol or hydroquinone in addition to repeat units derived from bisphenol A. The incorporation of resorcinol-derived and hydroquinone-derived repeat units into a BPA-polycarbonate confers excellent melt flow properties, molding properties, solvent and heat resistance, while maintaining the excellent mechanical properties and transparency inherent in bisphenol A polycarbonate. Such copolycarbonates can be prepared by interfacial polymerization, melt polymerization, or solid state polymerization. The present invention relates to an improved method to prepare these and related copolycarbonates using the melt polymerization method. In conventional melt polycondensation processes, bisphenol A polycarbonate is prepared by reacting bisphenol A with diphenyl carbonate in a molten state. Generally a catalyst comprising a quaternary ammonium salt such as tetramethylammonium hydroxide (TMAH), and an alkali or alkali earth metal hydroxide, such as sodium hydroxide (NaOH), is used to catalyze the polymerization reaction. During the melt polymerization process the reactants and products are subjected to high temperature and low pressure while by-product phenol is distilled from the reaction mixture. While copolycarbonates comprising repeat units derived from relatively volatile dihydroxy aromatic compounds, such as resorcinol and hydroquinone, may be prepared in a similar fashion much of the volatile comonomer may be lost during the polymerization reaction. Loss of the volatile comonomer presents significant engineering challenges, and with them stark economic penalties, when attempting to manufacture copolycarbonate comprising repeat units derived from one or more relatively volatile dihydroxy aromatic compounds via the melt polymerization process. The present invention solves these and other problems and provides a method for preparing copolycarbonates which incorporates volatile comonomers with greater efficiency than known methods. BRIEF SUMMARY OF THE INVENTION The present invention provides a method of preparing a copolycarbonate, said method comprising contacting under melt polymerization conditions at least one first dihydroxy aromatic compound, and at least one second dihydroxy aromatic compound, with at least one diaryl carbonate having structure I wherein R 1 is independently at each occurrence a halogen atom, nitro group, cyano group, C 1 -C 20 alkyl group, C 4 -C 20 cycloalkyl group, or C 6 -C 20 aryl group; and p and q are independently integers 0-5; and at least one melt polymerization catalyst, said catalyst comprising at least one metal hydroxide and at least one quaternary phosphonium salt having structure II wherein R 2 -R 5 are independently a C 1 -C 20 aliphatic radical, C 4 -C 20 cycloaliphatic radical or a C 4 -C 20 aromatic radical, and X − is an organic or inorganic anion; said first dihydroxy aromatic compound having a boiling point at atmospheric pressure, said boiling point being less than about 340° C. In a further aspect the present invention relates to copolycarbonates prepared by the method of the present invention. DETAILED DESCRIPTION OF THE INVENTION The present invention may be understood more readily by reference to the following detailed description of preferred embodiments of the invention and the examples included therein. In the following specification and the claims which follow, reference will be made to a number of terms which shall be defined to have the following meanings: The singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not. As used herein the term “copolycarbonate” refers to polycarbonates incorporating repeat units derived from at least two dihydroxy aromatic compounds and includes and copolyestercarbonates, for example a polycarbonate comprising repeat units derived from resorcinol, bisphenol A, and dodecandioic acid. “BPA” is herein defined as bisphenol A or 2,2-bis(4-hydroxyphenyl)propane. As used herein, the term “copolycarbonate of bisphenol A” refers to a copolycarbonate comprising repeat units derived from BPA and at least one other dihydroxy aromatic compound. As used herein, the term “melt polycarbonate” refers to a polycarbonate made by the transesterification of a diaryl carbonate with a dihydroxy aromatic compound. “Catalyst system” as used herein refers to a catalyst or catalysts that catalyze the transesterification of a dihydroxy aromatic compound with a diaryl carbonate in the preparation of melt polycarbonate. “Catalytically effective amount” refers to an amount of a catalyst at which catalytic performance is exhibited. As used herein the term “Fries product” is defined as a structural unit of the product polycarbonate which upon hydrolysis of the product polycarbonate affords a carboxy-substituted dihydroxy aromatic compound bearing a carboxy group adjacent to one or both of the hydroxy groups of said carboxy-substituted dihydroxy aromatic compound. For example, bisphenol A polycarbonate prepared by a melt reaction method in which Fries reaction occurs, affords 2-carboxy bisphenol A upon complete hydrolysis of the product polycarbonate. The terms “Fries product” and “Fries group” are used interchangeably herein. The terms “Fries reaction” and “Fries rearrangement” are used interchangeably herein. As used herein the term “dihydroxy aromatic compound” means a an aromatic compound which comprises two hydroxy groups, for example a bisphenol such as bisphenol A or a dihydroxy benzene such as resorcinol. As used herein the term “hydroxy aromatic compound” means a phenol, such as phenol or p-cresol, comprising a single reactive hydroxy group. As used herein the term “aliphatic radical” refers to a radical having a valence of at least one comprising a linear or branched array of atoms which is not cyclic. The array may include heteroatoms such as nitrogen, sulfur and oxygen or may be composed exclusively of carbon and hydrogen. Examples of aliphatic radicals include methyl, methylene, ethyl, ethylene, hexyl, hexamethylene, and the like. As used herein the term “aromatic radical” refers to a radical having a valence of at least one comprising at least one aromatic group. Examples of aromatic radicals include phenyl, pyridyl, furanyl, thienyl, naphthyl, phenylene, and biphenyl. The term includes groups containing both aromatic and aliphatic components, for example a benzyl group. As used herein the term “cycloaliphatic radical” refers to a radical having a valance of at least one comprising an array of atoms which is cyclic but which is not aromatic. The array may include heteroatoms such as nitrogen, sulfur and oxygen or may be composed exclusively of carbon and hydrogen. Examples of cycloaliphatic radicals include cyclopropyl, cyclopentyl cyclohexyl, tetrahydrofuranyl and the like. As mentioned, the present invention provides a method of preparing a copolycarbonate said method comprising contacting under melt polymerization conditions at least one first dihydroxy aromatic compound, and at least one second dihydroxy aromatic compound, with at least one diaryl carbonate having structure I and at least one melt polymerization catalyst, said catalyst comprising at least one metal hydroxide and at least one quaternary phosphonium salt having structure II, said phosphonium salt comprising an anion X − which is an organic or inorganic anion, said first dihydroxy aromatic compound having a boiling point at atmospheric pressure less than about 340° C. As noted, the dihydroxy aromatic compound denoted the “first dihydroxy aromatic compound” has a boiling point of less than about 340° C., preferably less than about 320° C. and is more volatile than the dihydroxy aromatic compound designated the “second dihydroxy aromatic compound”. For example, let the first dihydroxy compound be hydroquinone which has a boiling point of about 285° C. and the second dihydroxy aromatic compound be bisphenol A which is considerably less volatile than hydroquinone. A key feature of the present invention is that the method allows a relatively volatile dihydroxy aromatic compound such as hydroquinone or resorcinol to be efficiently copolymerized with a less volatile dihydroxy aromatic compound such as bisphenol A and a diaryl carbonate such as diphenyl carbonate while minimizing loss of the more volatile dihydroxy aromatic compound as a result of its volatility and entrainment with the hydroxy aromatic compound by-product, for example phenol, formed during the melt polymerization reaction. Boiling points for a very large number of dihydroxy aromatic compounds are known in the chemical literature and may be found in readily available publications such as the Aldrich Handbook of Fine Chemicals and Laboratory Equipment 2003-2004 Edition which is available from the Sigma-Aldrich Corporation USA and which is incorporated herein by reference. Frequently, boiling points are given which reference pressures other than about atmospheric pressure. The boiling point at atmospheric pressure for a given compound may be estimated with reasonable accuracy using a boiling point nomograph, such as that found in P. H. Rhodes, The Organic Chemist's Desk Reference (1995), page 150. Thus, when referring to a first dihydroxy aromatic compound having a boiling point of less than about 340° C., it is meant that either the known boiling point at atmospheric pressure is less than 340° C. or its boiling point at atmospheric pressure estimated using a boiling point correction graph (nomograph) or like means, is less than about 340° C. Like means for estimating boiling points include a computer program designed to estimate boiling points at atmospheric pressure based upon known boiling points at pressures other than atmospheric pressure. Additional like means for estimating boiling points include estimation of boiling points within a homologous series. For example, hydroquinone has a boiling point of about 285° C. The boiling point of the next highest member in a homologous series of compounds based upon hydroquinone, methylhydroquinone, is estimated to be about 10 to 20° C. higher than that of hydroquinone itself based on the known effect on boiling point (bp) of an additional methylene group within a homologous series. This effect is illustrated by the boiling points of phenol (bp 182° C.), o-cresol (bp 191° C.), and m-cresol (bp 203° C.). Finally, like means for estimating boiling points include modern “ab initio” computational methods of determining boiling points. Typically, the first dihydroxy aromatic compound is selected from the group consisting of dihydroxy benzenes having structure III wherein R 6 is independently at each occurrence a halogen atom, or a C 1 -C 5 alkyl radical; and d is an integer from 0 to 4. Dihydroxy benzenes having structure III are illustrated by resorcinol; 4-methylresorcinol; 5-methylresorcinol; hydroquinone; 2-methylhydroquinone; 2-ethylhydroquinone; 2,5-dimethylhydroquinone; 2,6-dimethylhydroquinone; catechol; 3-methylcatechol; 4-methylcatechol; and a mixture thereof. As noted, said second dihydroxy aromatic compounds are less volatile than said first dihydroxy aromatic compounds. Typically, said second dihydroxy aromatic compound is a bisphenol having structure IV wherein R 7 is independently at each occurrence a halogen atom, nitro group, cyano group, C 1 -C 20 alkyl group, C 4 -C 20 cycloalkyl group, or C 6 -C 20 aryl group; n and m are independently integers 0-4; W is a bond, an oxygen atom, a sulfur atom, a SO 2 group, a C 1 -C 20 aliphatic radical, a C 6 -C 20 aromatic radical, a C 6 -C 20 cycloaliphatic radical or the group wherein R 8 and R 9 are independently a hydrogen atom, C 1 -C 20 alkyl group, C 4 -C 20 cycloalkyl group, or C 4 -C 20 aryl group; or R 8 and R 9 together form a C 4 -C 20 cycloaliphatic ring which is optionally substituted by one or more C 1 -C 20 alkyl, C 6 -C 20 aryl, C 7 -C 21 aralkyl, C 5 -C 20 cycloalkyl groups or a combination thereof. Bisphenols having structure IV are illustrated by 2,2-bis(4-hydroxyphenyl)propane (bisphenol A); 2,2-bis(3-chloro-4-hydroxyphenyl)propane; 2,2-bis(3-bromo-4-hydroxyphenyl)propane; 2,2-bis(4-hydroxy-3-methylphenyl)propane; 2,2-bis(4-hydroxy-3-isopropylphenyl)propane; 2,2-bis(3-t-butyl-4-hydroxyphenyl)propane; 2,2-bis(3-phenyl-4-hydroxyphenyl)propane; 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane; 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane; 2,2-bis(3,5-dimethyl-4-hydroxyphenyl )propane; 2,2-bis(3-chloro-4-hydroxy-5-methylphenyl)propane; 2,2-bis(3-bromo-4-hydroxy-5-methylphenyl)propane; 2,2-bis(3-chloro-4-hydroxy-5-isopropylphenyl)propane; 2,2-bis(3-bromo-4-hydroxy-5-isopropylphenyl)propane; 2,2-bis(3-t-butyl-5-chloro-4-hydroxyphenyl)propane; 2,2-bis(3-bromo-5-t-butyl-4-hydroxyphenyl)propane; 2,2-bis(3-chloro-5-phenyl-4-hydroxyphenyl)propane; 2,2-bis(3-bromo-5-phenyl-4-hydroxyphenyl)propane; 2,2-bis(3,5-disopropyl-4-hydroxyphenyl)propane; 2,2-bis(3,5-di-t-butyl-4-hydroxyphenyl)propane; 2,2-bis(3,5-diphenyl-4-hydroxyphenyl)propane; 2,2-bis(4-hydroxy-2,3,5,6-tetrachlorophenyl)propane; 2,2-bis(4-hydroxy-2,3,5,6-tetrabromophenyl)propane; 2,2-bis(4-hydroxy-2,3,5,6-tetramethylphenyl)propane; 2,2-bis(2,6-dichloro-3,5-dimethyl-4-hydroxyphenyl)propane; 2,2-bis(2,6-dibromo-3,5-dimethyl-4-hydroxyphenyl)propane; 1,1-bis(4-hydroxyphenyl)cyclohexane; 1,1-bis(3-chloro-4-hydroxyphenyl)cyclohexane; 1,1-bis(3-bromo-4-hydroxyphenyl)cyclohexane; 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane; 1,1-bis(4-hydroxy-3-isopropylphenyl)cyclohexane; 1,1-bis(3-t-butyl-4-hydroxyphenyl)cyclohexane; 1,1-bis(3-phenyl-4-hydroxyphenyl)cyclohexane; 1,1-bis(3,5-dichloro-4-hydroxyphenyl)cyclohexane; 1,1-bis(3,5-dibromo-4-hydroxyphenyl)cyclohexane; 1,1-bis(3,5-dimethyl-4-hydroxyphenyl)cyclohexane; 1,1-bis(3-chloro-4-hydroxy-5-methylphenyl)cyclohexane; 1,1-bis(3-bromo-4-hydroxy-5-methylphenyl)cyclohexane; 1,1-bis(3-chloro-4-hydroxy-5-isopropylphenyl)cyclohexane; 1,1-bis(3-bromo-4-hydroxy-5-isopropylphenyl)cyclohexane; 1,1-bis(3-t-butyl-5-chloro-4-hydroxyphenyl)cyclohexane; 1,1-bis(3-bromo-5-t-butyl-4-hydroxyphenyl)cyclohexane; 1,1-bis(3-chloro-5-phenyl-4-hydroxyphenyl)cyclohexane; 1,1-bis(3-bromo-5-phenyl-4-hydroxyphenyl)cyclohexane; 1,1-bis(3,5-disopropyl-4-hydroxyphenyl)cyclohexane; 1,1-bis(3,5-di-t-butyl-4-hydroxyphenyl)cyclohexane; 1,1-bis(3,5-diphenyl-4-hydroxyphenyl)cyclohexane; 1,1-bis(4-hydroxy-2,3,5,6-tetrachlorophenyl)cyclohexane; 1,1-bis(4-hydroxy-2,3,5,6-tetrabromophenyl)cyclohexane; 1,1-bis(4-hydroxy-2,3,5,6-tetramethylphenyl)cyclohexane; 1,1-bis(2,6-dichloro-3,5-dimethyl-4-hydroxyphenyl)cyclohexane; 1,1-bis(2,6-dibromo-3,5-dimethyl-4-hydroxyphenyl)cyclohexane; 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3-chloro-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3-bromo-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(4-hydroxy-3-methylphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(4-hydroxy-3-isopropylphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3-t-butyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3-phenyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3,5-dichloro-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3,5-dibromo-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3,5-dimethyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3-chloro-4-hydroxy-5-methylphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3-bromo-4-hydroxy-5-methylphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3-chloro-4-hydroxy-5-isopropylphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3-bromo-4-hydroxy-5-isopropylphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3-t-butyl-5-chloro-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3-bromo-5-t-butyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; bis(3-chloro-5-phenyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3-bromo-5-phenyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3,5-disopropyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3,5-di-t-butyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(3,5-diphenyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(4-hydroxy-2,3,5,6-tetrachlorophenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(4-hydroxy-2,3,5,6-tetrabromophenyl )-3,3,5-trimethylcyclohexane; 1,1-bis(4-hydroxy-2,3,5,6-tetramethylphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(2,6-dichloro-3,5-dimethyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 1,1-bis(2,6-dibromo-3,5-dimethyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; 4,4′dihydroxy-1,1-biphenyl; 4,4′-dihydroxy-3,3′-dimethyl-1,1-biphenyl; 4,4′-dihydroxy-3,3′-dioctyl-1,1-biphenyl; 4,4′-dihydroxydiphenylether; 4,4′-dihydroxydiphenylthioether; 1,3-bis(2-(4-hydroxyphenyl)-2-propyl)benzene; 1,3-bis(2-(4-hydroxy-3-methylphenyl)-2-propyl)benzene; 1,4-bis(2-(4-hydroxyphenyl)-2-propyl)benzene; and 1,4-bis(2-(4-hydroxy-3-methylphenyl)-2-propyl)benzene. In many applications due to its relatively high reactivity, thermal stability, and low cost, bisphenol A is preferred. As noted, diaryl carbonates having structural formula I are employed according to the method of the present invention. Diaryl carbonates having structure I are illustrated by diphenyl carbonate, bis(4-methylphenyl) carbonate, bis(4-chlorophenyl) carbonate, bis(4-fluorophenyl) carbonate, bis(2-chlorophenyl) carbonate, bis(2,4-difluorophenyl) carbonate, bis(4-nitrophenyl) carbonate, bis(2-nitrophenyl) carbonate, and bis(4-bromophenyl) carbonate. Diphenyl carbonate if frequently preferred. The melt polymerization catalyst employed according to the method of the present of the present invention is at least one quaternary phosphonium salt having structure II wherein R 2 -R 5 are independently a C 1 -C 20 aliphatic radical, C 4 -C 20 cycloaliphatic radical or a C 4 -C 20 aromatic radical, and X − is an organic or inorganic anion. Suitable anions X − are illustrated by hydroxide, halide, carboxylate, phenoxide, sulfonate, sulfate, carbonate, and bicarbonate. Carboxylate anions are frequently preferred. Where X − is a polyvalent anion such as carbonate or sulfate it is understood that the positive and negative charges in phosphonium salt II are properly balanced. For example, where R 2 -R 5 in structure II are each methyl groups and X − is carbonate, it is understood that X − represents ½ (CO 3 −2 ). Quaternary phosphonium salt having structure II are illustrated by tetramethylphosphonium hydroxide, tetraphenylphosphonium hydroxide, tetraphenylphosphonium acetate, tetramethylphosphonium formate, tetrabutylphosphonium hydroxide, and tetrabutylphosphonium acetate. Tetraphenylphosphonium acetate and tetrabutylphosphonium acetate are frequently preferred. The melt polymerization catalyst used according to the present invention, in addition to comprising a quaternary phosphonium salt also comprises a metal hydroxide. Typically, the metal hydroxide is an alkali metal hydroxide, for example sodium hydroxide, lithium hydroxide or potassium hydroxide, or an alkaline earth metal hydroxide, for example calcium hydroxide. Mixtures of one or more alkali metal hydroxides may be employed, as may be mixtures of one or more alkaline earth metal hydroxides. In addition, mixtures of one or more alkali metal hydroxides with one or more alkaline earth metal hydroxides may be employed as part of the melt polymerization catalyst system. In one embodiment of the present invention, at least one first dihydroxy aromatic compound and at least one second dihydroxy aromatic compound are employed in amounts such that the molar ratio of the first dihydroxy aromatic compound to the second dihydroxy aromatic compound is in a range between about 0.01 and about 4. Where the first dihydroxy aromatic compound comprises two or more compounds, for example a mixture of resorcinol and hydroquinone, and the second dihydroxy compound is a single compound, for example BPA, the molar ratio of the first dihydroxy aromatic compound to the second dihydroxy aromatic compound is expressed as the sum of the number of moles of resorcinol and hydroquinone used divided by the number of moles of BPA used. Similarly, where the first dihydroxy aromatic compound comprises but a single compound, for example resorcinol, and the second dihydroxy aromatic compound comprises a mixture of compounds, for example, BPA and BPZ (1,1-bis(4-hydroxyphenyl)cyclohexane), the molar ratio of the first dihydroxy aromatic compound to the second dihydroxy aromatic compound is expressed as the number of moles of resorcinol used divided by the sum of the number of moles of BPA and BPZ used. As mentioned, in one embodiment the molar ratio of the first dihydroxy aromatic compound to the second dihydroxy aromatic compound is in a range between about 0.01 and about 4. In an alternate embodiment said molar ratio of the first dihydroxy aromatic compound to the second dihydroxy aromatic compound is in a range between about 0.05 and about 0.7. A copolycarbonate prepared according to the method of the present invention using resorcinol as the first dihydroxy aromatic compound and BPA as the second dihydroxy aromatic compound in which the molar ratio of resorcinol to BPA was about 0.7 could contain as much as about 41 mole percent resorcinol derived repeat units if no loss occurred during the polymerization reaction. One aspect of the present invention is that loss of at least some of the more volatile monomer is inevitable under melt polymerization conditions which involve the removal from the reaction mixture by distillation of a significant amount of a hydroxy aromatic compound by-product, typically phenol, under conditions of high temperature and low pressure. In one aspect the method of the present invention minimizes the loss of the more volatile first dihydroxy aromatic compound from the polymerization mixture and maximizes the incorporation of repeat units derived from the first dihydroxy aromatic compound in the product copolycarbonate. Typically, the method of the present invention is carried out such that the amount of diaryl carbonate I employed corresponds to a molar ratio of diaryl carbonate I to all dihydroxy aromatic compounds, i.e. said first and said second dihydroxy aromatic compounds, initially present in the reaction mixture, said molar ratio being in a range between about 0.90 and about 1.20, preferably between about 1.01 and about 1.10. The term “contacting under melt polymerization conditions” will be understood to mean those conditions necessary to effect reaction between the diary carbonate and the dihydroxy aromatic compounds employed according to the method of the present invention. The reaction temperature is typically in the range between about 150° C. and about 350° C., more preferably between about 180° C. and about 310° C. The pressure may be at atmospheric pressure, supraatmospheric pressure, or a range of pressures, for example from about 2 atmospheres to about 15 torr in the initial stages of the polymerization reaction, and at a reduced pressure at later stages, for example in a range between about 15 torr and about 0.1 torr. The reaction time is generally in a range between about 0.1 hours and about 10 hours, preferably between about 0.1 and about 5 hours. In order to achieve the formation of copolycarbonate using the method of the present invention an effective amount of catalyst must be employed. The amount of catalyst employed is typically based upon the total number of moles of first dihydroxy aromatic compound and second dihydroxy aromatic compound employed in the polymerization reaction. When referring to the ratio of catalyst, for example phosphonium salt II, to all dihydroxy aromatic compounds employed in the polymerization reaction, it is convenient to refer to moles of phosphonium salt “per mole of said first and second dihydroxy aromatic compounds combined”, meaning the number of moles of phosphonium salt divided by the sum of the moles of each individual dihydroxy aromatic compound present in the reaction mixture. Typically the amount of phosphonium salt II employed will be in a range between about 1×10 −2 and about 1×10 −5 , preferably between about 1×10 −3 and about 1×10 −4 moles per mole of said first and second dihydroxy aromatic compounds combined. Typically the metal hydroxide catalyst will be used in a an amount corresponding to between about 1×10 −4 and about 1×10 −8 , preferably 1×10 −4 and about 1×10 −7 moles of metal hydroxide per mole of said first and second dihydroxy aromatic compounds combined. The method of the present invention may be employed to provide both high molecular weight copolycarbonates. High molecular weight copolycarbonates are defined as copolycarbonates having a weight average molecular weight, M W , greater than 15,000 daltons. The method of the present invention may also be employed to provide oligomeric copolycarbonates. Oligomeric copolycarbonates are defined as copolycarbonates as having weight average molecular weight, M W , less than 15,000 daltons. The copolycarbonate of Example 1 exemplifies a high molecular weight copolycarbonate while the copolycarbonate of Example 2 exemplifies an oligomeric copolycarbonate, each being prepared by the method of the present invention. In one aspect the method of present invention provides copolycarbonates comprising repeat units derived from at least two dihydroxy aromatic compounds, at least one of said dihydroxy aromatic compounds having a boiling point of about 340° C. or less. The copolycarbonates prepared according to method of the present invention are characterized as having lower Fries content than identically constituted copolycarbonates of the same molecular weight prepared by known methods. In one embodiment, the present invention provides a copolycarbonate comprising repeat units derived from at least one first dihydroxy aromatic compound and at least one second dihydroxy aromatic compound, said first dihydroxy aromatic compound having a boiling point at atmospheric pressure of less than about 340° C., said polycarbonate comprising residual phosphonium salt II or products derived from it in an amount corresponding to at least about three parts phosphorous per million parts of the copolycarbonate. The copolycarbonates prepared using the method of the present invention may be blended with conventional additives such as heat stabilizers, mold release agents and UV stabilizers and molded into various molded articles such as optical disks, optical lenses, automobile lamp components and the like. Typically injection molding is preferred. Further, the copolycarbonates prepared using the method of the present invention may be blended with other polymeric materials, for example, other polycarbonates, polyestercarbonates, polyesters and olefin polymers such as ABS. EXAMPLES The following examples are set forth to provide those of ordinary skill in the art with a detailed description of how the methods claimed herein are evaluated, and are not intended to limit the scope of what the inventors regard as their invention. Unless indicated otherwise, parts are by weight, and temperature is in degrees centigrade (° C.). Molecular weights are reported as number average (M n ) or weight average (M w ) molecular weight and were determined by gel permeation chromatography using polymer solutions comprising the product copolycarbonates at a concentration of about 1 milligram (mg) per milliliter (mL) in methylene chloride (CH 2 Cl 2 ). The molecular weights are referenced to polystyrene (PS) molecular weight standards. The composition of a given product copolycarbonate was determined by hydrolysis of the copolycarbonate to afford a solution of its constituent monomers. The solution was then diluted as appropriate and analyzed by high performance liquid chromatography (HPLC) to determine the weight percentages of the individual monomers present in the copolycarbonate. MELT POLYMERIZATIONS Reactions were carried out with BPA and different amounts of comonomer. In general the amount of comonomer employed is expressed in terms of its mole percentage. Mole percentage (mole %) as used herein is defined as 100×(number of moles of comonomer/(total moles monomer)). A slight excess of diphenyl carbonate (DPC) was employed, meaning that the amount of DPC expressed in moles was slightly greater than the stoichiometric amount required to effect complete reaction between all of the comonomers under ideal conditions. The slight excess of diphenyl carbonate is required because some of the DPC is lost due to volatilization particularly during the initial stages of the melt polymerization. In the Comparative Examples which follow the melt polymerization catalyst was tetramethylammonium hydroxide (TMAH) in combination with sodium hydroxide. In the Examples which follow the melt polymerization catalyst was tetrabutylphosphonium acetate (TBPA) in combination with sodium hydroxide. Catalysts were added as aqueous solutions, the volume added being about 100 microliters (□1). The melt polymerizations of Comparative Example 1 and Example 1 were carried out in a standard laboratory melt reactor constructed of glass and equipped for stirring a viscous melt and adapted for removal of volatile reaction by-products, for example phenol, at ambient or subambient pressure. The reactor was purged with nitrogen after being charged with reactants. The catalyst was added following the nitrogen purge. Upon completion of the melt polymerization reaction, the reactor was brought back to atmospheric pressure with a gentle nitrogen flow, and the polymer was recovered. Comparative Example 1 The melt reactor was passivated by acid washing, rinsing and drying with nitrogen gas, was charged with 19.73 g of BPA, 2.38 g of resorcinol, 25.00 g of DPC, and 100 μl of an aqueous solution of TMAH and NaOH in an amount corresponding to about 2.5×10 −4 moles TMAH and about 2.5×10 −6 moles NaOH per the total number of moles of BPA and resorcinol combined. The temperature-pressure regime used to carry out the melt polymerization comprised the steps of heating for the indicated time periods at the indicated temperatures and pressures: (1) 15 minutes, 180° C., atmospheric pressure, (2) 45 min, 230° C., 170 mbar, (3) 30 min, 270° C., 20 mbar, (4) 30 min, 300° C., 0.5-1.5 mbar, respectively. During steps 1-4 phenol by-product was removed from the reaction mixture by distillation. After the final reaction stage, the product copolycarbonate was recovered and analyzed. The product copolycarbonate had a weight average molecular weight (M w ) of about 55,300 daltons and comprised about 70 percent of the initial resorcinol employed. Example 1 The reaction was carried out as in Comparative Example 1 with the exception that the catalyst employed was 100 μl of an aqueous solution of TBPA and NaOH, said 100 μl of aqueous solution comprising TBPA and NaOH in an amount corresponding to about 1.0×10 −4 moles of TBPA and about 2.5×10 −6 Moles of NAOH per the total number of moles of BPA and resorcinol used in the melt polymerization. The temperature-pressure regime used to carry out the melt polymerization was identical to that used in Example 1. The product copolycarbonate had a weight average molecular weight (M w ) of about 54,800 daltons and comprised about 76 percent of the initial resorcinol employed. Comparative Example 2 Molten mixtures of reactants diaryl carbonate, resorcinol and BPA were prepared batchwise in two separate first melt mixing tanks and were alternately recharged to provide a continuous flow of the molten reactants to a single second melt mixing tank. The molten mixture was fed from the second melt mixing tank to a first continuous stirred tank reactor (CSTR) at a rate corresponding to about 2019 grams DPC per hour, 1574 grams BPA per hour and 201 grams of resorcinol per hour. A catalyst solution consisting of an aqueous solution of TMAH and sodium hydroxide was continuously introduced into the first CSTR at a rate of about 6mL per hour, the amount of TMAH corresponding to about 2.5×10 −4 moles TMAH added for each mole of BPA and resorcinol combined being introduced into the first CSTR. Similarly, the amount of NaOH being added corresponded to about 2.5×10 −6 moles NaOH for each mole of BPA and resorcinol combined being introduced into the first CSTR. The first CSTR was maintained at a temperature of about 225° C. and a pressure of about 170 mbar. The output the first CSTR was introduced into a second CSTR said second CSTR being maintained at a temperature and pressure of about 260° C. and about 20mbar. Each of the first and second CSTR's was equipped for the removal of phenol by-product. The product was an oligomeric copolycarbonate which emerged from the second CSTR at a rate of about 1.8kg per hour. The product oligomeric copolycarbonate had a weight average molecular weight (M w ) of about 5,600 daltons and comprised about 72 mole percent of the initial resorcinol employed. Example 2 The reaction was carried out as in Comparative Example 2 with the exception that the aqueous catalyst solution consisted of TBPA and NaOH. The amounts of TBPA and NaOH corresponded to about 1.25×10 −4 moles of TBPA and 2.5×10 −6 moles NaOH for each mole of BPA and resorcinol combined being fed. As in Comparative Example 2 the catalyst solution was added at about 6 mL per hour. The product was an oligomeric copolycarbonate which emerged from the second CSTR at a rate of about 1.8kg per hour. The product oligomeric copolycarbonate had a weight average molecular weight (M w ) of about 8,100 daltons and comprised about 82 mole percent of the initial resorcinol employed. Data for Examples 1 and 2 and Comparative Examples 1 and 2 are gathered in Table 1 and show that although some resorcinol is invariably lost during the melt polymerization reaction (Example 1 and Comparative Example 1) or during the continuous oligomerization of Example 2 and Comparative Example 2, the use of the quaternary phosphonium salt catalyst gives consistently higher levels of resorcinol incorporation into the product copolycarbonate (Example 1 and Comparative Example 1) or oligomeric copolycarbonate (Example 2 and Comparative Example 2) TABLE 1 HIGHER LEVELS OF CO-MONOMER RESORCINOL ACHIEVED THROUGH THE USE OF TBPA CATALYST % Resorcinol Example Catalyst M w Incorporated Comparative TMAH/NaOH 55300 70% Example-1 Example-1 TBPA/NaOH 54800 76% Comparative TMAH/NaOH 5600 72% Example-2 Example-2 TBPA/NaOH 8100 82% The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood by those skilled in the art that variations and modifications can be effected within the spirit and scope of the invention.

A melt polymerization method is presented which permits the efficient preparation of copolycarbonates in which one or more of the constituent dihydroxy. aromatic compounds employed is relatively volatile, having a boiling point of less than about 340° C. Relatively volatile dihydroxy aromatic compounds are illustrated by dihydroxybenzenes such as hydroquinone, methyl hydroquinone and resorcinol. Known methods for the preparation of members of this class of copolycarbonates, such as the melt reaction of bisphenol A and resorcinol diphenyl carbonate in the presence of sodium hydroxide and tetraalkylammonium salt catalyst systems, suffer losses in efficiency due to the resorcinol being entrained out of the polymerization mixture with by-product phenol. Catalyst systems including quaternary phosphonium salts are shown to have improved performance with respect to the amount of volatile dihydroxy aromatic compound actually incorporated into the product copolycarbonate.

RELATED APPLICATIONS This application is a continuation of U.S. application Ser. No. 12/697,537, filed Feb. 1, 2010, now U.S. Pat. No. 9,101,570, which claims the benefit of U.S. application Ser. No. 61/152,417, filed Feb. 13, 2009. The entire teachings of the above applications are incorporated herein by reference. BACKGROUND OF THE INVENTION Field of Invention The invention relates to a method of treating diabetes. There are two types of diabetes, type 1 (T1D) and type 2 (T2D). About 10% of all Americans diagnosed with diabetes (more than 700,000) have T1D while the remaining other 90% of Americans that have diabetes, have type 2 diabetes. T2D (often referred to as adult onset diabetes) affects nearly 20 million people in the US. (CDC 2007) Diabetes, both T1D and T2D is the leading cause of blindness, renal failure and amputations, and patients have demonstrably shorter life spans. Increasingly diabetes is being understood as a metabolic disorder. This insight is leading to a new sort of pathology—the creation of inflammatory stress and an altered interaction between organ systems and between organ systems and the immune system resulting from the metabolism of certain substances. The evidence suggests that the organs themselves and the immune system are not impaired, but rather, they receive incorrect signals originating in the foregut due to the interaction of improper metabolites and the organ system. These signals then cause an improper cellular balance and function. While the dysfunction of the foregut in T1D and T2D is different, the original source of the incorrect signals leading to the pathology of the disease starts in the foregut. Prior Art T2D is a disease characterized by insulin insensitivity. Under normal circumstances, pancreatic islet cells release insulin in response to elevated levels of glucose in the bloodstream. Insulin drives glucose into peripheral tissues for use in building tissue and storing energy. However, in the setting of certain diets in susceptible individuals, glucose and insulin production is constantly switched on. As a protective mechanism, tissues subsequently become increasingly insensitive to insulin. Thus, T2D is a disease in which the environment (certain diets) damages the cellular niche of the foregut which triggers excess glucose production by the liver, which causes excess insulin production by the pancreas leading to insulin insensitivity in susceptible individuals. T2D is caused by environmental insults due to the type of food consumed with the portion of the small intestine first exposed to food exiting the stomach most severely impacted. These environmental insults damage cellular niches in vulnerable individuals leading to the improper stimulation of the foregut during food digestion. Specifically, an imbalance of metabolites resulting from food digestion in the duodenum sends incorrect signals to the liver that over produces glucose that causes the pancreas to over produce insulin. Physiologic responses are eventually blunted as a protective mechanism in the face of constant signaling. Consequently, cells begin to look insulin resistant because there is too much glucose and insulin in the system. Overstressed pancreatic islets die because they cannot keep up with the required insulin production to overcome the excess amount of glucose being produced by the liver and the increasing insulin resistance of cells. In addition, some metabolites produced by the duodenum during food digestion need to communicate through nerve endings in the portal vein to signal hunger suppression to the brain. Advanced hyperglycemia damages these nerve endings exacerbating the problem. The following can be summarized as: 1) An improperly functioning duodenum that produces an imbalance of metabolites resulting in the excess production of glucose by the liver, insulin resistance, leading to a pancreatic burden that ends in islet necrosis; and 2) Improper hunger suppression due to damaged nerves primarily in the portal vein. The combination of points 1 and 2 explains the high correlation between T2D and obesity. Biliopancreatic diversion (BPD) and Roux-en-Y gastric bypass (RYGBP) effectively bypass the diseased portion of the intestinal tract so that the foregut (duodenum) is excluded and the distal small bowel becomes the new foregut. The distal small bowel is less impacted over time from the environmental insult that lead to the duodenum dysfunction because it is farther removed from the source of the insult which is certain partially undigested foods exiting the stomach. Consequently, immediately after the surgery, this undamaged portion of the small bowel becomes the new foregut, is attached to the stomach and remarkably, begins to produce proper metabolites in response to food intake. Thus, within days of surgery, blood sugar levels of patients return to a normal range and there is an increase in the release of certain hormones like GLP-1 that promote satiety. Interestingly, resolution of T2D following surgery is inversely proportional to duration of the disease; those who have had the disease for longer period of times prior to surgery experience lower rates of resolution. The longer a patient has lived with the disease, the greater the portion of the small bowel that is damaged, the greater the damage to the islets of the pancreas, and the greater the damage to nerve endings in the portal vein due to the prolonged impact of hyperglycemia. With respect to type 1 diabetes (T1D), the goal of researchers is to 1) halt the progression of Type 1 diabetes (T1D) by re-introducing tolerance between the immune system and the pancreas and 2) regenerate the insulin producing capacity of the pancreas. Increasingly T1D is being understood as a metabolic disorder. This insight is leading to a new sort of Pathology—the creation of inflammatory stress and an altered interaction between the organ systems and the immune system resulting from the metabolism of certain substances. The evidence suggests that the immune system is itself not impaired, but rather, it receives incorrect signals due to the interaction of improper metabolites and the organ system. These signals then cause an improper cellular balance and function. We believe that the cause of type 1 diabetes originates in the small intestine. The primary functions of the gastrointestinal tract have traditionally been perceived to be limited to the digestion and absorption of nutrients and electrolytes, and to water homeostasis. A more attentive analysis of the anatomic and functional arrangement of the gastrointestinal tract, however, suggests that another extremely important function of this organ is its ability to regulate the trafficking of macromolecules between the environment and the host through a barrier mechanism. Together with the gut-associated lymphoid tissue and the neuroendocrine network, the intestinal epithelial barrier, with its intercellular tight junctions, controls the equilibrium between tolerance and immunity to nonself-antigens. When the finely tuned trafficking of macromolecules is deregulated due to certain environmental insults (most likely due to the ingestion of certain foods or pathogens) in genetically susceptible individuals, both intestinal and extra-intestinal autoimmune disorders can occur. Supporting this explanation are observations that diet modifies the incidence of diabetes and the phenotype of T-cells infiltrating the islets of Langerhans in animal models (NOD mice) of Type 1 diabetes. T-cells infiltrating the islets of Langerhans in Type 1 diabetics and in experimental models of autoimmune diabetes are intestinal in origin since they exhibit the b7-integrin receptor (gut associated homing receptor). Mesenteric lymphocytes from non-obese diabetic (NOD) mice can transfer diabetes to healthy recipients. We believe that concentrated nucleated cells injected into this environment can re-establishing proper intestinal function and arrest the autoimmune process by changing the interplay between altered epigenes and the environment. We believe that the cause of type 1 diabetes originates in the small intestine. Specifically, T1D patients have an altered intestinal immune responsiveness. This altered mucosal immune system has been associated with the disease of T1D and is likely a major contributor to the failure to form tolerance, resulting in the autoimmunity that underlies type 1 diabetes. There are numerous cell types in the small intestine that play a role in proper immune system function, including the following: Intraepithelial Lymphocytes. Intraepithelial lymphocytes (IELs) are located at the basolateral side of the epithelial layer. Here they are exposed to a wide range of food and microbial antigens. One well-established function of IELs is their ability to protect the host from invasion by microorganisms that enter through the gastrointestinal tract. One subtype, the intestinal epithelial lymphocytes, are also at the mucosal interface and appear to play a key role in maintaining peripheral tolerance. Intestinal Epithelial Cells. Intestinal epithelial cells (IEGs) comprise the lining epithelium of the primitive intestine with the role of transduction of inflammatory signals from luminal microbes via toll-like receptors and other signaling mechanisms. These cells serve as the permeability barrier between the external and internal milieus of the body. M-Cells. M-cells do not have well-developed microvilli and allow macromolecular transport, are specialized for delivering foreign antigens and microorganisms to organized lymphoid tissues within the mucosa of the small and large intestines. Goblet Cells. Goblet cells are specialized mucus-secretory cells found throughout the intestine. Intestinal mucus is a complex gel that covers the surface of the villous epithelium and contributes significantly to cytoprotection, offering many ecological advantages for the microbiota. Paneth Cells. Paneth cells represent one of the four major epithelial cell lineages in the small intestine and are the only lineage that migrates downward into the crypt base after originating in the crypt stem cell region. The location of Paneth cells adjacent to crypt nucleated cells suggests that they play a critical role in defending epithelial cell renewal. In response to pathogen attack, the Paneth cells secrete a wide spectrum of antimicrobial peptides against gram-negative and gram-positive bacteria, fungi, protozoa, and viruses. The focus of research and therapy for T1D has been on pancreatic islet regeneration through various methods to include allogeneic islet transplantation, venous or arterial infusion of concentrated marrow nucleated cells into the area of the pancreas, nonmyeloablative immune conditioning followed by a systematic autologous or allogeneic stem cell transplantation and immune suppression drugs. Unfortunately, there is no cure for T1D and patients diagnosed with this disease require exogenous insulin injections to live. The focus of research and therapy for T2D has been on drugs to improve insulin sensitivity, weight loss through surgery or diet, and more recently, a Teflon sleeve that covers the duodenum. This sleeve allows the passage of food from the stomach to the distal portion of the small intestine without having the food contact the duodenum. All of the major functions of the body are related. The source of diabetes is the foregut and when this organ is impaired, it results in incorrect protein signals being produced that cause problems in other organs. In the case of T1D, the incorrect signals cause the immune system to attack cells that make insulin. In the case of T2D, the incorrect signals cause the liver to overproduce glucose which then makes the pancreas have to over produce insulin and results in insulin insensitivity in peripheral tissues. The focus of prior art for both T1D and T2D has been on organs and tissues which are damaged as a result of diabetes, with the primary focus being the pancreas. We believe in the case of both disease states, the focus needs to be on the organ (ie the gastrointestinal tract) the disease emanates from, and not the organs downstream (ie pancreas and other peripheral tissues) that are damaged as a result of the malfunctioning gastrointestinal tract. U.S. Pat. No. 6,808,702 provides a method of implantation of stem cells into a gastrointestinal organ for purposes of repopulating various cellular components and I or providing a source of biological material for therapeutic intent. The source of these stem cells can be embryonic or adult neural and non-neural tissue, (e.g. bone marrow or fat tissue) U.S. Pat. No. 6,808,702 goes on to define a gastrointestinal organs to include hollow and solid organs. Hollow gastrointestinal organs include those that make up the alimentary tract, such as the mouth, esophagus, stomach, and bowels. Solid gastrointestinal organs include those that drain into the gastrointestinal alimentary tract such as the liver, gall bladder and pancreas. With respect to diabetes, U.S. Pat. No. 6,808,702 teaches that it is a disease of a solid organ as defined by the patent as a gastrointestinal organ and not a hollow organ as defined by the patent. Specifically, U.S. Pat. No. 6,808,702 teaches a method of producing enhanced levels of insulin in a patient by implanting stem cells and/or progeny thereof into the pancreas, which is considered a gastrointestinal organ as defined by the patent because it is a solid organ that drains into the gastrointestinal alimentary tract. For example U.S. Pat. No. 6,808,702 states“ Further, this invention can also be used to provide therapy for disorders that are not traditionally considered gastrointestinal disorders but are related to organs that are considered gastrointestinal organs (e.g. liver, gall bladder, and pancreas) in that the organs drain into the gastrointestinal alimentary canal. Such disorders include diabetes, which can be treated by means of implantation of stem cells into the pancreas of a patient to cause enhancement of insulin production.” It is important to note that U.S. Pat. No. 6,808,702 broadly defines gastrointestinal organs to include the pancreas; goes on to define diabetes as not being thought of as a gastrointestinal disorder; and instructs that stem cells be injected into the pancreas (a solid organ) as a possible therapy for diabetes. It is important to note that U.S. Pat. No. 6,808,702 states that diabetes is not traditionally thought of as a gastrointestinal disorder and specifically teaches away from the art disclosed here by instructing the injection of stem cells into the solid organ pancreas. The art disclosed here is patently different from what is disclosed in U.S. Pat. No. 6,808,702. This art narrowly defines gastrointestinal tract to include hollow organs that make up the alimentary tract to include the stomach and bowels but does not include any solid organs. Opposed to the traditional view that diabetes is not a gastrointestinal disorder as taught by U.S. Pat. No. 6,808,702; the art disclosed herein specifically identifies diabetes as a disease that originates in the hollow organs of the gastrointestinal tract and not of the solid organ pancreas. This art then goes on to specifically teach that an effective therapy for diabetes is to implant nucleated cells from various tissues into the hollow organs of the gastrointestinal tract, specifically the duodenum. Conversely, U.S. Pat. No. 6,808,702 broadly defines gastrointestinal organs to include the pancreas, defines diabetes as being a disease of the solid organ pancreas, and in the art teaches to inject into the solid organ of the pancreas. Some of the prior art referred to above use treating compositions that contain nucleated cells to include nucleated cells from bone marrow aspirates, fat aspirates, or mobilized peripheral blood. Specifically, the prior art teaches the delivery of the cells into the venous or arterial system. However, none of the prior art is delivering the nucleated cells directly into the appropriate tissue. This art teaches a method of injecting the treating composition directly into the tissue of gastrointestinal tract with a focus on the foregut. In view of the above, the present invention seeks to improve clinical outcomes by delivering a treating composition into the foregut which is the source of the disease. Compositions that contain nucleated cells are an obvious choice to include in the composition because nucleated cells have the demonstrated ability to regulate the cellular activity of surrounding cells and to repair the function of damaged tissue and immune systems. Tissues whose nucleated cell population are rich in cells that contain sub populations that are often referred to as stem cells include bone marrow aspirate, fat aspirate, cord blood, mobilized peripheral blood, Wharton's jelly, and other after birth tissue. Since diabetes ultimately damages other organ systems, it is reasonable to combine the treatment of the foregut with a method of treating other tissue affected by the disease. Thus combining a method of delivering cells into the foregut with a systemic delivery of nucleated cells into the venous or arterial system is appropriate. SUMMARY OF THE INVENTION Diabetes can be reversed through the repair the duodenum by implanting concentrated nucleated cells that include nucleated cells from various sources directly into the wall of the duodenum through an endoscopic procedure. The implantation can be carried out via local injection, as for example into a wall of the duodenum. This therapy can be augmented by combining direct injection into the gastrointestinal tract of the treating composition with arterial or venous delivery. Several different tissue sources rich in nucleated cell populations that contain nucleated cells can be used alone or in combination in preparing the treating composition. DETAILED DESCRIPTION OF THE INVENTION T2D can be reversed through the repair of the duodenum by injecting concentrated nucleated cells from various sources directly into the wall of the duodenum through an endoscopic procedure. This procedure can be combined with introducing a portion of the treating composition into the portal vein and or duodenal artery through a catheter based procedure. This procedure should 1) reset/repair the proper function of digestion and metabolite production in the duodenum and 2) repair of the nerve endings of the portal vein. The result will be an improvement in establishing normal glucose levels, support for the regeneration of the insulin producing capacity of the pancreas, improvement in insulin resistance, and the re-establishment of hunger suppression signals in response to food intake. Consequently, the therapy should be effective for both T2D and the co-morbidity of obesity associated with T2D. The progression of T1D can be halted prior to the destruction of the pancreas by re-setting of the immune system. This can be accomplished through the repair of the small intestine by injecting a treating composition of nucleated cells into the wall of the duodenum through an endoscopic procedure to reset/repair the interaction between the immune system and the insulin producing islets of the pancreas. DRAWINGS-FIGURES FIG. 1 is a perspective view for explaining one embodiment of the present invention; FIG. 2 is a perspective view for explaining an embodiment of the present invention whereby the cells are sourced from the patient being treated. DETAILED DESCRIPTION—FIRST EMBODIMENT—FIGS 1 In the interest of clarity, numerous different surgical protocols and surgical devices currently available can be used to implant a treating composition into the wall of the gastrointestinal tract. Also, numerous different methodologies can be used for concentrating nucleated cells from the various tissues mentioned above in order to create the treating composition. The source of the cells can be the patient themselves or from other donors. Some of these tissues can be sourced, concentrated and delivered at point of care. Other sources of cells can be sourced, processed in a laboratory, and then delivered to the patient. It will, of course, be appreciated that in the development of any surgical protocol designed to implement the art described, numerous implementation-specific decisions must be made in order to fit a particular patient's profile and that these specific protocols will vary from one surgeon and patient to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. For example, different injection patterns, needle gauges, and combinations of nucleated cells from various sources can be used to create and deliver the treating composition. The treating composition can be delivered through and endoscopic procedure or during an open procedure. In addition to cells, other types of treating compositions could be delivered in combination or individually as part of the treating composition that contain for example, platelets, growth factors or other proteins or therapeutic agents to include pharmaceuticals. FIG. 1 is a perspective view of the stomach ( 102 ) which is connected to the foregut. ( 103 ) Several different endoscopic surgical tools exist to access the gastrointestinal tract and to inject cells into the wall of the duodenum. ( 100 ) Such tools are flexible in nature and are designed to move easily through the curved space within the gastrointestinal tract. These same tools can be used to implant a treating composition directly into the walls of the tissue comprising the gastrointestinal tract. Such direction injections can move in a spiral pattern along the walls of the tissue. ( 104 , 105 , 106 ) FIG. 2 is a perspective of a surgical protocol of treating a patient ( 200 ) with tissue rich in stem cells sourced from their own body. ( 201 ) This tissue is then processed to concentrate the nucleated cells including the stem cells. ( 202 ) Such methods of concentration can be done point of care during same procedure as the sourcing of the cells and the delivery of the cells to the gastrointestinal tract. The treating composition is then delivered through and endoscopic tool ( 203 ) to the hollow organs of the gastrointestinal tract that include the stomach ( 206 ) and foregut ( 207 .) Other organs such as the liver ( 204 ) and gallbladder ( 205 ) and pancreas (not shown) can also be treated by infusing a portion of the treating composition into the venous or arterial system. In accordance with the present invention, the method of sourcing, concentrating, and delivering directly a treating composition rich in nucleated cells to include stem cells into the tissue of the foregut may be implemented using various types of laboratory and or surgical equipment. Thus the scope of the invention should be determined by the appended claims and their legal equivalents, and not by the examples given. It will be appreciated that numerous different methods exist to concentrate the nucleated cells from various tissue to include bone marrow aspirate and fat aspirate. These methods can employ off site laboratory methods or devices designed to be used at the patients side (ie point of care) For example, their exists several centrifugation based protocols such as a ficoll separation method, cell washing technology, and apheresis technology for removing a large portion of the non-nucleated red blood cells and plasma from marrow aspirate and or cord blood. Such methods are well known in the art. For removing the extracellular matrix material from fat, whartons jelly, and other solid tissues, several well known protocols such as enzymatic digestion with collagenase are well known in the art. With all of these protocols, some material such as plasma and red cells remain in the concentrate. Definitions: Gastrointestinal tract means hollow organs and include the alimentary tract to include the stomach and bowels. T1D means type 1 diabetes. T2D means type 2 diabetes. Nucleated cell means a cell that contains a nucleus.

The anatomic and functional arrangement of the gastrointestinal tract suggests an important function of this organ is its ability to regulate the trafficking of metabolites as well as control the equilibrium between tolerance and immunity through gut-associated lymphoid tissue, the neuroendocrine network, and the intestinal epithelial barrier. Combining nucleated cells from various tissues and introducing them directly into the small intestine will have a positive effect on diabetes.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to image communication apparatus which has at least one of communication control unit for receiving and transmitting image data of different resolutions on at least one communication line and which also has an image memory for storing image data to be transmitted. 2. Description of the Prior Art The CCITT (International Telegraph and Telephone Consulting Committee of the International Telecommunications Union) recommends several standard facsimile apparatuses, including: Group 1 (Gl), Group 2 (G2), Group 3 (G3) and Group 4 (G4). Facsimile apparatus of the G1, G2 and G3 type use public analog telephone lines, whereas facsimile apparatus of the G4 type mainly use digital communication lines. Picture element density or image resolution is different between G3 and G4 types of facsimile apparatus. The standard picture element density used in the G3 type is 8 pels. (picture elements)/mm (millimeter) in the main scanning direction, and 3.85 pels/mm sub scanning direction. On the other hand, the picture element density of the G4 type facsimile apparatus is 200 pels/inch (7.87 pels/mm) in both the main and sub scanning directions. A standard encoding/decoding method known as the MH (Modified Huffman) method, is generally used for encoding and decoding image signals in a G3 type facsimile apparatus whereas a method known as MMR (Modified Modified READ) is generally used for encoding and decoding image signals in a G4 type facsimile apparatus. Applicants have previously proposed facsimile apparatus which has both G3 and G4 facilities. FIG. 2 shows the block diagram of such dual function facsimile apparatus. As shown in FIG. 2 there is provided an image reading unit 1 for reading an original image to be transmitted. The reading unit 1 reads the original image and converts the original image to an image signal. There is also provided an image printing unit 2, for example a thermal printer, which prints an image corresponding to a received image signal. The facsimile apparatus of FIG. 2 also includes a digital communication control unit 8. This control unit connects the apparatus with digital communication lines; and it controls communications in the manner of a G4 facsimile apparatus with encoding/decoding according to the MMR method. The apparatus of FIG. 2 also includes an analog communication control unit 9 which connects the apparatus with an analog communication line, for example a telephone line; and carries out modulation/demodulation and encoding/decoding according to the MH method. There is also provided a reading unit 1 and a printing unit 2 which are connected to an image memory 5 via, respectively, an encoding circuit 3 and a decoding circuit 4. The G4 communication control unit 8 and the G3 communication control unit 9 are connected via the encoding/decoding circuits 6 and 7, respectively, to the image memory 5. The image memory 5 is a random access memory device, for example a semiconductor device or a hard-disc apparatus. The above described units are controlled by a control unit (not shown) such as a microprocessor or the like. The apparatus shown in FIG. 2 transmits an image signal, read from an original by the reading unit 1, to an analog or digital communication line via the analog or digital communication control unit 8 or 9. The signal from the reading unit 1 is communicated through the path E or C in the memory 5 shown in FIG. 2. The apparatus of FIG. 2 also supplies the recording Unit 2 with an image signal from an analog or digital communication line. The image signal is received by the analog or digital communication unit 8 or 9, and is supplied through the memory 5. The signal to the printing unit is communicated through the path A or F in the memory 5 shown in FIG. 2. In addition, image signals may be transmitted directly from the reading unit 1 to the printing unit 2 through a path D in the memory 5; and image signals may be transmitted between an analog and a digital communication line through the communication control units 8 and 9 and a path B in the memory 5. Generally, in the above-described transfer of image data, in order to make efficient use of the image memory 5, the memory is arranged to store the image data as encoded by the encoding circuit 3 and the encoding/decoding circuits 6 and 7. It does not matter which one of the above-mentioned coding processes (i.e. MH or MMR) is used by the encoding circuit 3, the decoding circuit 4 and the encoding/decoding circuit 6 and 7. The differences between the G3 and G4 type communication control units involve not only their respective encoding methods, but also the image resolution. For example, the image resolution of the reading unit 1 and the printing unit 2 in both the main and the sub-scanning directions is generally 400 ppi (picture elements per inch), which is available for both the G3 and G4 type information processing. In this case, the image data obtained by the reading unit 1 may be sent to the printing unit 2 through the path D in the image memory 5, and the image data is copied. Here the size of the read image is the same as the size of the printed or reproduced image. However, the image resolution of the G3 type image data from the analog communication line which is received via the communication control unit 9 is, as above mentioned, 8 pel/mm in the main scanning direction and 3.85 pel/mm in the sub scanning direction (i.e. 8×3.85 pel/mm). Therefore the image resolution of the printing unit 2 is larger than that of the G3 type image data, so that the G3 image data obtained via the path A should be reduced in both the main and sub scanning directions. Similarly, when a relaying operation from the analog line to the digital line is carried out through the path B, the image resolution of the G3 image data should be converted to compensate for the difference between the resolution of the G3 image data and that of the G4 image data. When the read image data is to be transmitted via the communication control unit 8 to the G4 digital data line, the image resolution of the G4 image data must be half of that of the reading unit 1; and accordingly the resolution of the image data read by the reading unit 1 must be halved. Also, when the image data read by the reading unit 1 is to be transmitted via the communication control unit 9 to the G3 analog date line, the resolution of the image data read by the reading units should be also converted. As can be appreciated from the foregoing, because the system of FIG. 2 inputs and outputs image data or different image resolution, it is necessary to provide image resolution converting circuits at several positions shown by P1, P2 and P3, in order to communicate between all the combinations of apparatus which operate with different image resolutions. Therefore, the structure of the above-described system is complicated and costly. SUMMARY OF THE INVENTION The present invention overcomes the above described problem by providing an image communication apparatus which has a memory for storing image data and which comprises image data supply means for supplying first and second image data of different resolutions, respectively, and an image data resolution converter connected between the image data supply means and the memory to convert the resolution of at least one of the first and second image date such that the resolution of the first and second image data supplied to the memory is unified. Because of the novel arrangement of the present invention wherein the resolution of the image data to the memory is unified, the density of the picture elements is at a fixed predetermined value whenever image data is input to the image memory and whenever image data is output from the image memory. Consequently, the image data may always be processed by the same method in spite of the different communication facilities which communicate image data of different resolutions. Thus, the overall structure of the apparatus is simplified. There has thus been outlined rather broadly the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures or methods for carrying out the several purposes of the invention. It is important, therefore, that the claims be regarded as including such other constructions and methods as do not depart from the spirit and scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS One embodiment of the invention has been chosen for purposes of illustration and description, and is shown in the accompanying drawings forming a part of the specification, wherein: FIG. 1 is a block diagram of a facsimile apparatus according to the present invention; and FIG. 2 is a block diagram of a conventional facsimile apparatus. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The facsimile apparatus of FIG. 1 incorporates both G3 and G4 communication facilities. As shown in FIG. 1, there is provided an image memory 23 for storing an image data which is to be input to and output from the apparatus. The image memory 23 may comprise a RAM (random access semiconductor memory) or a hard disc memory apparatus, both of well known conventional design. An encoding circuit 24 is provided for encoding by a predetermined encoding method (i.e. MMR type in the illustrated embodiment) the image data for storage in the image memory 23. A decoding circuit 25 is provided for decoding the image data output from the image memory 23. The resolution of the image data in the image memory 23 is unified at 400 ppi. Thus, the image data in the image memory 23 is MMR encoded and has a resolution of 400 ppi. The encoding and decoding circuit 24 and 25 are well known per se and accordingly are not described in further detail. In this present embodiment there are also provided, as inputting/outputting devices to the image memory 23, an image reading unit 21, an image printing unit 22, a communication control unit 27 for G3 type communication and a communication control unit 26 for G4 type communication. The reading and printing units 21 and 22 are also well known and are therefore not described in further detail herein. The image reading unit 21 and the image printing unit 22 have an image resolution of 400 ppi. Therefore, it is possible to connect the image reading unit 21 directly to the encoding circuit 24 and to connect the image printing unit 22 directly to the decoding circuit 25. On the other hand, the image resolutions of G3 and G4 type communication are different from the 400 ppi resolution of the reading and printing units 21 and 22. Therefore, in the case of inputting or outputting between the image memory 23 and the communication control units 26 or 27, it is necessary to convert the image resolution. For this purpose image resolution converters 28, 29, 210 and 211 are provided. As shown, the control unit 26 sends received image data signals to the image resolution converter 28 via a signal line 2a, and the control unit 27 sends received image data signals to the image resolution converter 29 via a signal line 2c. Also the control unit 26 receives image data signals to be transmitted via a signal line 2b from the image resolution converter 210 and the control unit 27 receives image data signals to be transmitted via a signal line 2d from the image resolution converter 211. The image resolution converters 28, 29, 210 and 211 convert the resolution of binary image data which is not encoded. Firstly, the image resolution converter 28 converts the 200×200 ppi image resolution of the G4 type communication to a 400×400 ppi image resolution. Therefore, for example, one input picture element is converted to two output picture elements in the main and subsidiary scanning directions. The image resolution converter 29 converts the 8×3.85 pels/mm resolution of the G3 type communication to the 400×400 ppi image resolution. In this case, for example, one input picture element is converted to two output picture elements, and one element of every 64 output picture elements is deleted in the main scanning direction. In the subsidiary scanning direction, one line of input image signals is converted to four lines of output image signals, and one line of output image signals are added at every 180 lines of output image signals. The added one-line image signals are the same as those of the line which is just prior to this line. The image resolution converter 210 converts the 400×400 ppi image data to the 200×200 ppi image data of the G4 type communication. Therefore, two input picture elements are converted into one output picture element in both of the main and subsidiary scanning directions. The image resolution converter 211 converts the 400×400 ppi input image data to 8×3.85 pels/mm output image data. Therefore, two input picture elements are converted to one output picture elements except that two input picture element are converted to two output picture elements every 63 input picture elements. The above-described image resolution converters, respectively, comprise line memories, and counters for controlling the input or output image data to the line memories or from the line memories. These devices are well known per se and accordingly are not described in further detail herein. Four switches, 212-215, for example analog switches, connect the image reading unit 21, the image printing unit 22, the encoding circuit 24, the decoding circuit 25 and the image resolution converters 28, 29, 210 and 211. Each of the switches 212-215 connects a selected input or output apparatus to the image memory 23. As can be seen, the switch 212 has a common terminal connected via a signal line 2m to the encoding circuit 24, which the switch 213 has a common terminal connected via a signal line 2n to the decoding circuit 25. A control unit 20, which includes a micro processor, a memory and well known associated elements, controls the switches 212-215. In the embodiment of FIG. 1, the image data is in all cases input or output by using one of the image reading unit 21, image printing unit 22, and the communication control units 26 and 27; and the image data must be buffered in the image memory 23. The image resolution of the image data in the image memory 23 is always 400×400 ppi; and the image data in the image memory 23 is MMR encoded. In the case of reading an image, the switch 212 is changed over to a signal line 2i, so that the image reading unit 21 is connected to the encoding unit 24. Therefore the 400×400 ppi image data read by the image reading unit 21 is MMR encoded and is stored in the image memory 23. Also, in the case of transmitting image data in accordance with G4 type communication, the switch 213 is changed over to connect a signal line 2n to a signal line 21, and the switch 215 is changed over to connect the signal line 21 to a signal line 2g. Therefore, the image data read out from the image memory 23 is decoded by the decoding circuit 25, and converted to 200×200 ppi image data by the image resolution converter 210. The 200×200 ppi image data is input to the communication control unit 26, and the communication control unit 26 transmits the image data to the digital communication line in accordance with G4 type communication. On the other hand, in the case of transmitting image data in accordance with G3 type communication, the switch 215 is changed over to the signal line 2h in order to connect the image memory 23 to the G3 communication control unit 27 via the decoding circuit 25 and the image resolution converter 211. Therefore the image data decoded by the decoding circuit 25 is converted to 8×3.85 pels/mm image data by the image resolution converter 211, and is transmitted to the analog communication line via the communication control unit 27. In the case of inputting G3 type image data received via the communication control unit 27 to the image memory 23, the switch 214 is changed over to a signal line 2f, and the switch 212 is changed over to a signal line 2j. Therefore the received image data from the communication control unit 27 is input to the image memory 33 via the image resolution converter 29 and the encoding circuit 24. Consequently, the image data stored in the image memory has 400×400 ppi image resolution and is MMR encoded. In the case of receiving image data in accordance with G4 type communication, the switch 214 is changed over to the signal line 2e, so that the received image data is input to the image memory 23 via the communication control unit 26, the image resolution converter 28 and the MMR encoding circuit 24. Consequently, the received the image data is converted to 400×400 ppi image data, is encoded, and is stored in the image memory 23. Further, in the case of printing image data which had been input to the image memory 23 from the image reading unit 21 and/or the communication control unit 26 or 27, the switch 213 is changed over to a signal line 2k, so that he output of the decoding circuit 25 is applied directly to the image printing unit 22. As a result the decoded image data is printed by the printing unit 22 without being converted. Image data received via either G3 (analog) communication control unit 27 or G4 (digital) communication control unit 26 and stored in the image memory 23 can be transmitted or relayed via either G4 (digital) communication control unit 26 or G3 (analog) communication control unit 27. It will be understood that the switches 212, 213, 214 and 215 are shown in FIG. 1 as mechanical switches only for purposes of explaining the principles and operation of the invention and that in actual practice the switching may be accomplished electronically, for example by means of solid state integrated circuit elements, e.g. multiplexer. It should be understood that some G4 type image communication facilities have a resolution of 400×400 ppi, which is the same as that of the other image data to be supplied to the image memory 23. In this case the image converter 28 and 210, shown if FIG. 1, would be eliminated. As described above, image resolution is unified in all cases of data input to the image memory 23 or data output from the image memory 23. Therefore, the hardware structure of the facsimile apparatus and the control for changing over the switches can easily be simplified. Further more, the resolution of the image data in the image memory is greater than that of both the G3 and G4 type communication, so that the image data can be transmitted and/or received with high quality by the both type of communication without deteriorating the original image quality. As also described in detail above, the present invention provides an image communication apparatus which has the image memory for storing the image data to be transmitted and which comprises a plurality of communication control units for respectively transmitting and/or receiving image data by different communication facilities. The apparatus also comprises control means for unifying resolution of the image data to be stored in the image memory. Therefore the image data can be input and/or output with high and homogeneous quality and facility irrespective of how it is selected. Also, by means of the present invention, the structure of a facsimile apparatus capable of handling different types of communication can be simplified and made less costly than prior art devices. Although a particular embodiment of the invention is herein disclosed for purposes of explanation, various modifications thereof, after study of this specification, will be apparent to those skilled in the art to which the invention pertains.

Apparatus used for processing facsimile image data of different resolutions. The apparatus includes a memory for storing received image data, circuits for supplying first and second image data of different resolutions to the memory and an image resolution converter arranged in the supply circuits for unifying the resolution of the data stored in the memory. A switch arrangement is provided for directing the image data of selected resolution among the elements.

This application is a continuation-in-part of U.S. patent application Ser. No. 10/195,796, filed Jul. 15, 2002 now U.S. Pat. No. 6,691,516, and assigned to the same assignee hereof. BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to a fuel and air injection apparatus and method of operation for use in a gas turbine combustor for power generation and more specifically to a device that reduces the emissions of nitrogen oxide (NOx) and other pollutants by injecting fuel into a combustor in a premix condition. 2. Description of Related Art In an effort to reduce the amount of pollution emissions from gas-powered turbines, governmental agencies have enacted numerous regulations requiring reductions in the amount of emissions, especially nitrogen oxide (NOx) and carbon monoxide (CO). Lower combustion emissions can be attributed to a more efficient combustion process, with specific regard to fuel injectors and nozzles. Early combustion systems utilized diffusion type nozzles that produce a diffusion flame, which is a nozzle that injects fuel and air separately and mixing occurs by diffusion in the flame zone. Diffusion type nozzles produce high emissions due to the fact that the fuel and air burn stoichiometrically at high temperature. An improvement over diffusion nozzles is the utilization of some form of premixing such that the fuel and air mix prior to combustion to form a homogeneous mixture that burns at a lower temperature than a diffusion type flame and produces lower NOx emissions. Premixing can occur either internal to the fuel nozzle or external thereto, as long as it is upstream of the combustion zone. Some examples of prior art found in combustion systems that utilize some form of premixing are shown in FIGS. 1 and 2 . Referring to FIG. 1 , a fuel nozzle 10 of the prior art for injecting fuel and air is shown. This fuel nozzle includes a diffusion pilot tube 11 and a plurality of discrete pegs 12 , which are fed fuel from conduit 13 . Diffusion pilot tube 11 injects fuel at the nozzle tip directly into the combustion chamber through swirler 14 to form a stable pilot flame. Though this pilot flame is stable, it is extremely fuel rich and upon combustion with compressed air, this pilot flame is high in nitrogen oxide (NOx) emissions. Another example of prior art fuel nozzle technology is the fuel nozzle 20 shown in FIG. 2 , which includes a separate, annular manifold ring 21 and a diffusion pilot tube 22 . Fuel flows to the annular manifold ring 21 and diffusion pilot tube 22 from conduit 23 . Diffusion pilot tube 22 injects fuel at the nozzle tip directly into the combustion chamber through swirler 24 . Annular manifold ring 21 provides an improvement over the fuel nozzle of FIG. 1 by providing an improved fuel injection pattern and mixing via the annular manifold instead of through radial pegs. The fuel nozzle shown in FIG. 2 is described further in U.S. Pat. No. 6,282,904, assigned to the same assignee as the present invention. Though this fuel nozzle attempts to reduce pollutant emissions over the prior art, by providing an annular manifold to improve fuel and air mixing, further improvements are necessary regarding a significant source of emissions, the diffusion pilot tube 22 . The present invention seeks to overcome the shortfalls of the fuel nozzles described above by providing a fuel nozzle that is completely premixed, thus eliminating all sources of a diffusion flame, while still being capable of providing a stable pilot flame for a constant combustion process. SUMMARY AND OBJECTS OF THE INVENTION It is an object of the present invention to provide a premixed fuel nozzle for a gas turbine engine that reduces NOx and other air pollutants during operation. It is another object of the present invention to provide a premixed fuel nozzle with an injector assembly comprising a plurality of radially extending fins to inject fuel and air into the combustor such that the fuel and air premixes, resulting in a more uniform injection profile for improved combustor performance. It is yet another object of the present invention to provide, through fuel hole placement, an enriched fuel air shear layer to enhance combustor lean blowout margin in the downstream flame zone. It is yet another object of the present invention to provide a premixed fuel nozzle with improved combustion stability through the use of a plurality of fuel injection orifices located along a conical surface of the premixed fuel nozzle. It is yet another object of the present invention to provide an alternate embodiment of the present invention comprising a plurality of radially extending fins to inject fuel only, wherein the nozzle body is configured to reduce blockage between adjacent fins. In accordance with these and other objects, which will become apparent hereinafter, the instant invention will now be described with particular reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a cross section view of a fuel injection nozzle of the prior art. FIG. 2 is a cross section view of a fuel injection nozzle of the prior art. FIG. 3 is a perspective view of the present invention. FIG. 4 is a cross section view of the present invention. FIG. 5 is a detail view in cross section of the injector assembly of the present invention. FIG. 6 is an end elevation view of the nozzle tip of the present invention. FIG. 7 is a cross section view of the present invention installed in a combustion chamber. FIG. 8 is a perspective view of an alternate embodiment of the present invention. FIG. 9 is a detail view in cross section of an alternate embodiment of the injector assembly of the present invention. FIG. 10 is a perspective view of a second alternate embodiment of the present invention. FIG. 11 is a cross section view of a second alternate embodiment of the present invention. FIG. 12A is a detailed perspective view of the injector assembly in accordance with the second alternate embodiment of the present invention. FIG. 12B is a detailed perspective view of the nozzle tip in accordance with the second alternate embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A premix fuel nozzle 40 is shown in detail in FIGS. 3 through 6 . Premix fuel nozzle 40 has a base 41 with three through holes 42 for bolting premix fuel nozzle 40 to a housing 75 (see FIG. 7 ). Extending from base 41 is a first tube 43 having a first outer diameter, a first inner diameter, a first thickness, and opposing first tube ends. Within premix fuel nozzle 40 is a second tube 44 having a second outer diameter, a second inner diameter, a second thickness, and opposing second tube ends. The second outer diameter of second tube 44 is smaller than the first inner diameter of first tube 43 thereby forming a first annular passage 45 between the first and second tubes, 43 and 44 , respectively. Premix fuel nozzle 40 further contains a third tube 46 having a third outer diameter, a third inner diameter, a third thickness, and opposing third tube ends. The third outer diameter of third tube 46 is smaller than said second inner diameter of second tube 44 , thereby forming a second annular passage 47 between the second and third tubes 44 and 46 , respectively. Third tube 46 contains a third passage 48 contained within the third inner diameter. Premix nozzle 40 further comprises an injector assembly 49 , which is fixed to each of the first, second, and third tubes, 43 , 44 , and 46 , respectively, at the tube ends thereof opposite base 41 . Injector assembly 49 includes a plurality of radially extending fins 50 , each of the fins having an outer surface, an axial length, a radial height, and a circumferential width. Each of fins 50 are angularly spaced apart by an angle α of at least 30 degrees and fins 50 further include a first radially extending slot 51 within fin 50 and a second radially extending slot 52 within fin 50 , a set of first injector holes 53 located in the outer surface of each of fins 50 and in fluid communication with first slot 51 therein. A set of second injector holes, 54 and 54 A are located in the outer surface of each of fins 50 and in fluid communication with second slot 52 therein. Fixed to the radially outermost portion of the outer surface of fins 50 to enclose slots 51 and 52 are fin caps 55 . Injector assembly 49 is fixed to premix nozzle 40 such that first slot 51 is in fluid communication with first passage 45 and second slot 52 is in fluid communication with second passage 47 . Premix nozzle 40 further includes a fourth tube 80 having a generally conical shape with a tapered outer surface 81 , a fourth inner diameter, and opposing fourth tube ends. Fourth tube 80 is fixed at fourth tube ends to injector assembly 49 , opposite first tube 43 and second tube 44 , and to third tube 46 . The fourth inner diameter of fourth tube 80 is greater in diameter than the third outer diameter of third tube 46 , thereby forming a fourth annular passage 82 , which is in fluid communication with second passage 47 . Premix fuel nozzle 40 further includes a cap assembly 56 fixed to the forward end of fourth tube 80 and includes an effusion plate 57 having an end surface including a set of third injector holes 58 therein. The use of a conical shaped tube as fourth tube 80 allows a smooth transition in flow path between injector assembly 49 and cap assembly 56 such that large zones of undesirable recirculation, downstream of fins 50 , are minimized. If the recirculation zones are not minimized, they can provide an opportunity for fuel and air to mix to the extent that combustion occurs and is sustainable upstream of the desired combustion zone. The premix fuel nozzle 40 , in the present embodiment, injects fluids, such as natural gas and compressed air into a combustor of a gas turbine engine for the purposes of establishing a premixed pilot flame and supporting combustion downstream of the fuel nozzle. One operating embodiment for this type of fuel nozzle is in a dual stage, dual mode combustor similar to that shown in FIG. 7. A dual stage, dual mode combustor 70 includes a primary combustion chamber 71 and a secondary combustion chamber 72 , which is downstream of primary chamber 71 and separated by a venturi 73 of reduced diameter. Combustor 70 further includes an annular array of diffusion type nozzles 74 each containing a first annular swirler 76 . Premix fuel nozzle 40 of the present invention is located along center axis A—A of combustor 70 , upstream of second annular swirler 77 , and is utilized as a secondary fuel nozzle to provide a pilot flame to secondary combustion chamber 72 and to further support combustion in the secondary chamber. In operation, flame is first established in primary combustion chamber 71 , which is upstream of secondary combustion chamber 72 , by an array of diffusion-type fuel nozzles 74 , then a pilot flame is established in secondary combustion chamber 72 . Fuel flow is then increased to secondary fuel nozzle 40 to establish a more stable flame in secondary combustion chamber 72 , while flame is extinguished in primary combustion chamber 71 , by cutting off fuel flow to diffusion-type nozzles 74 . Once a stable flame is established in secondary combustion chamber 72 and flame is extinguished in primary combustion chamber 71 , fuel flow is restored to diffusion-type nozzles 74 and fuel flow is reduced to secondary fuel nozzle 40 such that primary combustion chamber 71 now serves as a premix chamber for fuel and air prior to entering secondary combustion chamber 72 . The present invention will now be described in detail with reference to the particular operating environment described above. In the preferred embodiment, the premix nozzle 40 operates in a dual stage dual mode combustor 70 , where premix nozzle 40 serves as a secondary fuel nozzle. The purpose of the nozzle is to provide a source of flame for secondary combustion chamber 72 and to assist in transferring the flame from primary combustion chamber 71 to secondary combustion chamber 72 . In this role, the second passage 47 , second slot 52 , and second set of injector holes 54 and 54 A flow a fuel, such as natural gas into plenum 78 where it is mixed with compressed air prior to combusting in secondary combustion chamber 72 . During engine start-up, first passage 45 , first slot 51 , and first set of injector holes 53 flow compressed air into the combustor to mix with the fuel. In an effort to maintain machine load condition when the flame from primary combustion chamber 71 is transferred to secondary combustion chamber 72 , first passage 45 , first slot 51 , and first set of injector holes 53 flow fuel, such as natural gas, instead of air, to provide increased fuel flow to the established flame of secondary combustion chamber 72 . Once the flame is extinguished in primary combustion chamber 71 and securely established in secondary combustion chamber 72 , fuel flow through the first passage 45 , first slot 51 , and first set of injector holes 53 of premix nozzle 40 is slowly cut-off and replaced by compressed air, as during engine start-up. During this entire process, compressed air is flowing through third passage 48 and third set of injector holes 58 to provide adequate cooling to the nozzle cap assembly 56 . NOx emissions are reduced through the use of this premix nozzle by ensuring that all fuel that is injected is thoroughly mixed with compressed air prior to reaching the flame front of the combustion zone. This is accomplished by the use of the fin assembly 49 and through proper sizing and positioning of injector holes 53 , 54 , and 54 A. Thorough analysis has been completed regarding the sizing and positioning of the first and second set of injector holes, such that the injector holes provide a uniform fuel distribution. To accomplish this task, first set of injector holes 53 , having a diameter of at least 0.050 inches, are located in a radially extending pattern along the outer surfaces of fins 50 as shown in FIG. 3 . To facilitate manufacturing, first set of injector holes 53 have an injection angle relative to the fin outer surface such that fluids are injected upstream towards base 41 . Second set of injector holes, including holes 54 on the forward face of fins 50 and 54 A on outer surfaces of fin 50 , proximate fin cap 55 , are each at least 0.050 inches in diameter. Injector holes 54 A are generally perpendicular to injector holes 54 , and have a slightly larger flow area than injector holes 54 . Second set of injector holes 54 and 54 A are placed at strategic radial locations on fins 50 so as to obtain an ideal degree of mixing which both reduces emissions and provides a stable shear layer flame in secondary combustion chamber 72 . To further provide a uniform fuel injection pattern and to enhance the fuel and air mixing characteristics of the premix nozzle, all fuel injectors are located upstream of second annular swirler 77 . In the preferred embodiment, compressed air flows through third set of injector holes 58 for cooling the cap assembly 56 . Cooling efficiency is enhanced when using effusion cooling due to the amount of material that is cooled for a given amount of air. That is, an angled cooling hole has a greater surface area of hot material that is cooled using the same amount of cooling air as other cooling methods. In order to provide an effective cooling scheme for the cap assembly, the third set of injector holes 58 , which are located in effusion plate 57 , have an injection axis that intersects the end surface of effusion plate 57 at an angle β up to 20 degrees relative to an axis perpendicular to the end surface of effusion plate 57 , and have a diameter of at least 0.020 inches. An alternate embodiment of the present invention is shown in FIGS. 8 and 9 . The alternate embodiment includes all of the elements of the preferred embodiment as well as a fourth set of injector holes 83 , which are in communication with fourth annular passage 82 of fourth tube 80 . These injector holes provide an additional source of fuel for combustion. The additional fuel from fourth set of injector holes 83 premixes with fuel and air, from injector assembly 49 , in passage 78 (see FIG. 7 ) to provide a more stable flame, through a more fuel rich premixture, in the shear layer of the downstream flame zone region 90 . Fourth set of injector holes 83 are placed about the conical surface 81 of fourth tube 80 , between injector assembly 49 and cap assembly 56 , and have a diameter of at least 0.025 inches. A second alternate embodiment of the present invention is shown in FIGS. 10-12 . A premix fuel nozzle 140 has a base 141 with three through holes 142 for bolting premix fuel nozzle 140 to a housing. Referring to FIGS. 10 and 11 , a first tube 143 extends from base 141 having a first outer diameter, a first inner diameter, a first thickness, and opposing first tube ends. Within premix fuel nozzle 140 and coaxial with first tube 143 is a second tube 144 having a second outer diameter, a second inner diameter, a second thickness, and opposing second tube ends. The second outer diameter of second tube 144 is smaller than the first inner diameter of first tube 143 thereby forming a first annular passage 145 between the first and second tubes, 143 and 144 , respectively. Premix fuel nozzle 140 further contains a third tube 146 having a third outer diameter, a third inner diameter, a third thickness, and opposing third tube ends. The third outer diameter of third tube 146 is smaller than said second inner diameter of second tube 144 , thereby forming a second annular passage 147 between second and third tubes, 144 and 146 , respectively. Third tube 146 contains a third passage 148 within the third inner diameter. Premix fuel nozzle 140 further comprises an injector assembly 149 , which is fixed to both first and second tubes, 143 and 144 , respectively, at the tube ends thereof opposite base 141 . Injector assembly 149 includes a plurality of radially extending fins 150 , each of the fins having an outer surface, an axial length, a radial height, and a circumferential width. Referring to FIGS. 11 and 12A , fins 150 are angularly spaced apart by an angle α of at least 30 degrees and further include a radially extending slot 151 that is in fluid communication with second annular passage 147 . Located in the outer surface of each fin 150 is a set of first injector holes 152 that are in fluid communication with radially extending slots 151 and preferably have a diameter of at least 0.040 inches. Fixed to the radially outermost portion of the outer surface of fins 150 , to enclose slots 151 , are fin caps 153 . Injector assembly 149 also includes a set of second injector holes 154 that are in fluid communication with first passage 145 , located upstream of and circumferentially offset from fins 150 . Second injector holes preferably have a diameter of at least 0.150 inches. Referring back to FIGS. 10 and 11 , premix nozzle 140 further includes a fourth tube 180 having a generally conical shape with a tapered outer surface 181 , a fourth inner diameter, and opposing fourth tube ends. Fourth tube 180 is fixed at a fourth tube end to injector assembly 149 , opposite first tube 143 and second tube 144 , and is in sealing contact with third tube 146 at the fourth tube inner diameter. Referring now to FIGS. 11 and 12B , fixed to a fourth tube end opposite injector assembly 149 is a cap assembly 156 having a fifth outer diameter, a fifth inner diameter, and an effusion plate 157 with a third set of injector holes 158 . It is preferred that each of third injector holes 158 has a diameter of at least 0.020 inches and an injection axis that intersects the outer surface of effusion plate 157 at an angle β between 25 degrees and 90 degrees. The use of a conical shaped tube as fourth tube 180 allows for a smooth transition in flow path between injector assembly 149 and cap assembly 156 such that large zones of undesirable recirculation, downstream of fins 150 , are minimized. If the recirculation zones are not minimized, they can create a region for fuel and air to mix to the extent that combustion can occur and be sustainable upstream of the desired combustion zone. The second alternate embodiment of the present invention, premix nozzle 140 , preferably operates in a dual stage dual mode combustor. The purpose of the nozzle is to provide a flame source for a secondary combustion chamber and to assist in transferring a flame from a primary combustion chamber to a secondary combustion chamber. Initially compressed air flows through first passage 145 and is injected into the surrounding airstream through second injector holes 154 while a fuel, such as natural gas, flows through second passage 147 , slots 151 , and is injected into the surrounding airstream through first injector holes 152 . Then, in an effort to maintain machine load while transferring the flame from the primary combustion chamber to the secondary combustion chamber, first passage 145 and second injector holes 154 flow a fuel, such as natural gas, instead of air, to provide an enriched fuel flow to the secondary combustion chamber. Once the flame is extinguished in the primary combustion chamber and securely established in secondary combustion chamber, fuel flow through first passage 145 and second set of injector holes 154 of premix nozzle 140 is slowly cut-off and replaced with compressed air, as during initial operation. During this entire process, compressed air is flowing through third passage 148 and third set of injector holes 158 to provide adequate cooling to the nozzle cap assembly 156 . Prior embodiments of the present invention included second injector holes in the fins of the injector assembly. It has been determined through extensive analysis that the flow exiting from the second injector holes, when placed in the fins, penetrates far enough into the main flow of compressed air passing between the fins to block part of the compressed air from flowing in between the fins. As a result, less compressed air mixes with the fuel injected from first injector holes thereby resulting in increased fuel/air ratio, especially when second injector holes are flowing fuel. While an increased fuel supply provides a more stable flame, emissions tend to be higher. Analysis results indicate that this blockage is on the order of approximately 10% of the total flow area. Further compounding the blockage issue in the previous embodiments is the flow disturbance created by sharp corners along the upstream side of fins 50 . In the second alternate embodiment, fins 150 have rounded edges along the upstream side, creating a smoother flow path along the fin outer surfaces. By placing second injector holes 154 in injector assembly 149 adjacent first outer tube 143 , thereby eliminating a portion of the fins, the overall geometry of injector assembly 149 is simplified. Each of the improvements outlined herein leads to improved fuel nozzle performance by reducing the amount of flow blockage between adjacent fins while simplifying the configuration for manufacturing purposes. While the invention has been described in what is known as presently the preferred embodiment, it is to be understood that one skilled in the art of combustion and gas turbine technology would recognize that the invention is not to be limited to the disclosed embodiment but, on the contrary, is intended to cover various modifications and equivalent arrangements within the scope of the following claims.

A premix fuel nozzle and method of operation for use in a gas turbine combustor is disclosed. The premix fuel nozzle utilizes a fin assembly comprising a plurality of radially extending fins for injection of fuel and compressed air in order to provide a more uniform injection pattern. The fuel and compressed air mixes upstream of the combustion chamber and flows into the combustion chamber as a homogeneous mixture. The premix fuel nozzle includes a plurality of coaxial passages, which provide fuel and compressed air to the fin assembly, as well as compressed air to cool the nozzle cap assembly. An alternate embodiment includes an additional fuel injection region located along a conically tapered portion of the premixed fuel nozzle, downstream of the fin assembly. A second alternate embodiment is disclosed which reconfigures the injector assembly and fuel injection locations to minimize flow blockage issues at the injector assembly.

BACKGROUND [0001] Embodiments of the present invention provide a “revenues increasing the budget” feature for financial management software modules that are commonly found in enterprise management applications. [0002] Enterprise management applications (“EMAs”), such as the R/3 application commercially available from SAP AG, permit computer systems to manage the business operations of some of the largest organizations in the world. EMAs include several integrated systems, including financial management systems, materials management systems, financial accounting systems, fund management systems, asset management systems, and the like. [0003] “Ledgers” are a well known component of financial management software. Generally, a ledger represents a view into general transaction data according to a predetermined filtering scheme. For example, a first ledger, typically a general ledger, may be established to distinguish different expense types such as materials, infrastructure, salary, etc., according to a predetermined chart of accounts. A second, different ledger may be established to distinguish (and thus track) different projects or funds managed by the organization according to perhaps different accounting principles. Other ledgers might be set up to reflect additional aspects of the transaction data. [0004] “RIB” techniques are known per se in financial management software. RIB is an acronym for “revenues increasing the budget.” In many financial applications, expenditure budgets of a predetermined business unit such as an organization or department are based upon revenues of that business unit. Financial management software having RIB management features track revenues and determine changes to expenditure budget based upon predetermined rules. [0005] A RIB rule represents a transform from revenue information to expenditure budget information. Within the RIB rule, there may be defined: source addresses, representing locations of revenues, destination addresses, representing locations of expenditure budget, transform calculation, defining how expenditure budget is derived. Commonly, the transform calculation may define a transform coefficient (e.g., $1 increase in expenditure budget for every $2 in revenue), certain thresholds that must be exceeded before any increase in expenditure budget occurs (e.g., expenditure budget increased only after revenues exceed $100,000), or certain filtering conditions that occur as part of the calculation (e.g., increased expenditure budget occurs only for realized incoming payments, as opposed to customer invoices that have not been paid yet). [0009] In known RIB systems, increases of the expenditure budget are calculated directly from general ledger data. Modern EMAs, however, may operate on transaction databases having many millions of transaction items located therein. Depending on the rule by operating on the raw data, it might be not possible to perform the RIB rule sufficiently fast to have near real time calculation of RIB increases to budgetary values. Also auditing possibilities are limited. Accordingly, there is a need in the art for a RIB calculation feature that generates RIB budgetary values in near real time and tracks all the changes to allow for a complete auditing. BRIEF DESCRIPTION OF THE DRAWINGS [0010] FIG. 1 is a functional block diagram of a RIB management system according to an embodiment of the present invention. [0011] FIG. 2 is a process flow illustrating RIB rule execution according to an embodiment of the present invention. [0012] FIG. 3 illustrates exemplary RIB-generated budget items. [0013] FIG. 4 illustrates an exemplary budget data structure for use with embodiments of the present invention. [0014] FIG. 5 illustrates exemplary RIB rules for use with embodiments of the present invention. [0015] FIG. 6 illustrates a computing platform operable with embodiments of the present invention. DETAILED DESCRIPTION [0016] Embodiments of the present invention provide a RIB management system that permits calculation of RIB budgetary increases in near real time. As an EMA accepts new transactions that reflect posted revenue, the RIB management system determines whether the posted revenue is relevant to any RIB rule. If so, the RIB management system executes the RIB rule on the new revenue item, generating an incremental increase in budget. A “RIB ledger,” which is separate from and provided in addition to a general budget ledger, may store an aggregation of relevant revenues, an aggregation of reference revenue budget and the overall budget increase resulting from the RIB process up to that point in time. Each change of the RIB ledger can be documented using a corresponding line item for reporting purposes. The line item itself can refer to the original document (either budget or revenue posting) that caused the RIB ledger change, thus allowing for a complete change history reporting which might be requested, for example, for auditing reasons. [0017] FIG. 1 is a functional block diagram of a budgeting component 100 of a computerized accounting system according to an embodiment of the present invention. The system 100 may operate according to one or more “RIB rules” in which expenditure budget is generated from posted revenues realized by an organization. [0018] As shown, the system 100 may include a RIB ledger 110 , a transaction database 120 , a [0019] RIB rule manager 130 and a transaction system 140 . The RIB ledger 110 may include a RIB rule set 112 . The RIB rule set 112 typically is an object representing rules operable for the RIB ledger 110 . Each RIB rule 112 . 1 - 112 .N can include source addresses identifying locations of revenue items stored in the transaction database 120 that will potentially increase expenditure budget values. RIB rules also can include budget transforms, identifying how budget values are to be increased based upon new revenue (e.g., $1 of budget for every $2 of revenue, all revenue over $100M to be available as budget increase, etc.) and, of course, destination addresses in the transaction database 120 . These destination addresses identify locations in the transaction database 120 where new expenditure budget items generated pursuant to the RIB rules may be stored. [0020] The system 100 may be provided in communication with one or more terminals T via a communication network. During operation, the transaction system 140 receives transaction requests from one or more terminals and validates them. Typically, operators at the terminals T generate ‘documents’ representing one or more transactions. Modern ERP systems include multiple modules for processing and validating transactions of different types. Such functionality may be incorporated into the transaction system 140 . Documents for validated transactions may be stored in the transaction database 120 and values from different transactions may be stored in revenue entries therein. In this regard, the operation of a RIB rule system is well known. [0021] Embodiments of the present invention introduce a RIB database 114 into a RIB ledger. [0022] The RIB database 114 may include objects 114 . 1 - 114 .N for each RIB rule 112 . 1 - 112 .N in the RIB rule set 112 , which stores data relevant to the corresponding RIB rule. Thus, object 114 . 2 in the RIB database 114 may include an aggregation of all revenue values on which RIB rule 112 . 2 is based (ΣREVENUE). Objects 114 . 1 - 114 .N also may include an aggregation of all delta budget values calculated from earlier evaluations of the RIB rule (ΣΔBUDGET). If applicable to the corresponding RIB rule, an object 114 . 2 also may include an aggregation of reference revenue budget (ΣREV BUDGET); this may occur, for example, when RIB rules require a comparison to be made between actual revenue and reference revenue budget values before awarding a RIB increase to an expenditure budget. The structure of the RIB database, therefore, permits a fast calculation of additional delta budget values that may occur from a new transaction, which can lead to a near-real-time system. [0023] The RIB rule manager 130 may operate upon transaction data to determine if a new transaction is relevant to any RIB rule ( 112 . 1 - 112 .N). In so doing, the RIB rule manager 130 either may evaluate directly revenue items of a new transaction (or document) to be added to the transaction system 140 or may monitor changing aggregated revenue entries within the transaction database 120 . When a new document causes a change of an aggregated revenue entry in the transaction database 120 or if an aggregated revenue entry changes, without direct relation to a specific document added to the transaction system 140 , the RIB rule manager 130 may determine whether the entry is relevant to any RIB rule ( 112 . 1 - 112 .N). If so, the RIB rule manager 130 may cause the RIB rule (say, rule 112 .N) to be executed by accessing historical data stored in the corresponding object 114 .N of the RIB database 114 . As noted, an object 114 .N of the RIB database 114 may store: 1) aggregations of actual revenues that are relevant to the RIB rule 112 .N, 2) if appropriate to the corresponding RIB rule 112 .N, aggregations of reference revenue budget, and 3) overall expenditure budget increases from prior operation of the RIB rule 112 .N. Evaluation of the RIB rule 112 .N may generate a delta (expenditure) budget value (Δbudget), which may update budgetary values in the transaction database 120 and in the RIB database 114 of the RIB ledger. The RIB database object 114 .N also may have stored therein data referring to the posted transaction that caused the RIB change, such as updates to the aggregated values of the relevant actual revenues and of the reference revenue budget, and optionally single revenue items or reference revenue budget items, and even pointers to the original documents. [0024] As noted, RIB rules vary in type and content. In one embodiment, a RIB rule may require a comparison between actual revenue values and a reference revenue budget value. In the example provided above where expenditure budget is permitted to increase only after revenues exceed $100,000, the $100,000 value may be stored in the transaction database 120 as a reference revenue budget value. Within the RIB rule set 112 , the corresponding RIB rule (say, rule 112 . 1 ) may include a pointer to the reference revenue budget values in the transaction database 120 . The corresponding RIB database object 114 . 1 also may store a copy of the reference revenue budget value (ΣREV BUDGET). Of course, for RIB rules that do not involve such a comparison, there may be no need to store such pointers or reference values in the RIB rule or the RIB database object. [0025] Provision of a separate RIB database also permits filtering of transaction data based on predetermined criteria. This permits for fast access to the filtered data, which can facilitate use of the RIB techniques in an online system. During use, a general ledger database may store records for millions of transactions. An iterative search for transactions that match preselected attribute data (e.g., all transactions of a given type or all transactions entered for a given group of business partners), likely would be too slow to be performed as an online check. RIB rules may be defined, however, for preselected transaction attribute data. In so doing, the RIB database may store data responsive to the defined filtering conditions. The contents of the RIB ledger database (in particular aggregations of relevant revenue and of reference revenue budget) would be assembled as new transaction data is entered. Access to such filtered data is made much faster than an iterative search through the transaction database or even a general ledger database. [0026] According to an embodiment, the system 100 may include multiple RIB ledgers (e.g., 110 , 110 - 1 , 110 - 2 ). In this embodiment, each RIB ledger may include its own RIB rule set 112 and RIB database 114 . The RIB ledgers each may operate independently from each other, so that execution of a RIB rule in one RIB ledger may but need not be accompanied by execution of a RIB rule in another RIB ledger. [0027] In one embodiment, multiple ledgers 110 - 1 , 110 - 2 permit the EMA to operate under different, independent RIB scenarios. For example, an organization may define two expenditure budgets to represent its operations: an operating budget and a budget estimate that may be a more optimistic estimate of its operations. The organization may define separate RIB rules to apply to each of the budgets. Provision of multiple ledgers, each of which operates independently of the other, permits an EMA to accommodate such operations. [0028] FIG. 2 is a flow diagram that illustrates RIB operations that may be performed by the system of FIG. 1 . According to an embodiment, when a new revenue item is posted, the system determines whether the revenue item is a source for any RIB rule (boxes 210 , 220 ). If it is, the system executes the corresponding RIB rule(s). In doing so, the method may read historical data from a corresponding record object of the RIB database (box 230 ). The historical data represents, in combination with the data of the new revenue item, the ‘operands’ of the executing RIB rule. It may include, as noted, aggregations of relevant revenue values previously posted in the system, aggregations of all delta budget values posted after earlier evaluations of RIB rules and perhaps reference revenue data on which a threshold comparison is to be made. The system may calculate a Δbudget value as determined by the RIB rule (box 240 ) and update the corresponding object of the RIB database with values from the revenue item (box 250 ). For example, the revenue aggregation may be supplemented to reflect the new revenue admitted to the system. Additionally, copies of transaction documents or pointers thereto may be stored in the object as references to the transaction data or to the original documents on which the calculation of the new Δbudget value is based. [0029] If the system is configured to perform an immediate budget increase (box 260 ), the method also may cause the Δbudget value to be stored in the RIB database object and the transaction database (boxes 270 - 280 ). If not, the method may store the Δbudget item to a buffer (box 290 ; e.g. as preliminary nota) for later storage. Typically, such buffering is performed if the system is configured to perform background updates of system values on a periodic basis (e.g., hourly, daily or weekly). Instead of a background process, other processes may be used to store the calculated Δbudget values in the RIB database and the transaction database in a later step. Such processes may be started manually or automatically, after the revenue item has been posted. [0030] FIG. 3 provides an example of how a budget item may evolve in the transaction database 120 or in a RIB ledger database 114 over time. In case 1 , there have been N iterations of the method performed on the budget entry, each of which generates an incremental Δbudget value (Δbudget 1 -Δbudget N ). A total budget value is available, labeled TOTAL BUDGET N , which represents the sum of all Δbudget values and a base budget, which may have been defined for the budget entry through some other means. Case 2 represents the budget item following posting of an N+1 st revenue item that has RIB ramifications for the budget item. When the Δbudget N+1 value becomes available, it may be stored in the database and a new TOTAL BUDGET value (TOTAL BUDGET N+1 ) may be obtained simply by adding the Δbudget N+1 value to the previous value, TOTAL BUDGET N . The new value, TOTAL BUDGET N+1 , may then be stored in the database, replacing the old value. [0031] Case 3 represents the budget items following posting of an L th revenue item that has RIB ramifications for the budget item. When the Δbudget L item becomes available, it may be stored in the database and a new TOTAL BUDGET value may be obtained simply by adding the Δbudget L value with the previously available TOTAL BUDGET L−1 value to obtain a new value TOTAL BUDGET L . As can be seen, even as the number of Δbudget items increases to several tens of thousands of entries, which can be typical for EMAs, the TOTAL BUDGET value may be computed from a very small number of source operands, namely the new transaction data as well as the previous TOTAL BUDGET. This renders the computation process very fast and can lead to near real-time results for such information. [0032] In addition to the budget items illustrated in FIG. 3 , a RIB database stores additional types of data. First, the RIB database stores aggregated values of relevant actual revenues and aggregated values of reference revenue budget. Second, it may store data representing the revenue items or the revenue budget items that caused an update of the aggregation values mentioned before. The RIB database also may store references to the original documents that generated the revenue items or revenue budget items or to the budget documents that may be created by the RIB process itself in order to increase the budget values of both databases. For example, common revenue documents include bills, sales orders, credit memos and the like. The electronic documents themselves are stored in the transaction database 120 . Additionally, other documents may be created in the RIB database 114 as desired to hold references to the original documents of the transaction database and to record all RIB relevant information online. [0033] In addition to simplifying the calculation of the incremental Δbudget values of the RIB process, the foregoing embodiments are convenient because they also provide a data structure that permits an operator to view a history of RIB relevant data values and the transactions that created them. Δbudget items, revenue items and supporting documents may be linked in the RIB database to permit easy access and review, for example for auditing purposes. [0034] As noted, the transaction database 120 of FIG. 1 may store both revenue items and budget items. Conventionally, it is appropriate to consider revenue items to be stored in a revenue (budget) data structure and expenditure items (to which the Δbudget values belong) in a(n expenditure) budget data structure. These two (budget) data structures can have, in some embodiments, similar structures. [0035] FIG. 4 illustrates a simplified budget data structure that may find application with the foregoing embodiments. In this budget data structure, an organization is shown having three departments A, B and C. Budget and revenues for department A includes elements A 1 and A 2 . Element A 1 further includes sub-elements A 1 . 1 , A 1 . 2 and A 1 . 3 . Budget and revenues for department C is comprised of elements C 1 , C 2 , C 3 , C 4 and C 5 . This budget data structure may be used for expenditure budget items including the Δbudget values and for revenue items. [0036] FIG. 5 provides examples of RIB rules 510 , 520 , 530 that may be used with the budget data structure of FIG. 4 . In one embodiment, each RIB rule 510 , 520 , 530 may include fields for source address(es) 540 , a budgetary transform 550 and destination address(es) 560 . Thus, as illustrated, RIB rule 510 uses revenue items related to nodes A 1 , A 1 . 1 , A 1 . 2 , and A 1 . 3 as operands and applies a transform that generates $0.50 for every $1 of revenue posted over a lower limit value calculated from a reference budget value. For such a rule, the budgetary transform field 550 may include a transform coefficient in field 551 . 1 (in this case it would be 0.50) and a reference revenue budget pointer 551 . 2 . A reference budget value (e.g., $100,000) may be stored in the transaction database 120 at a location specified by the pointer 551 . 2 . If the total revenue exceeds the reference budget value, a Δbudget value may be calculated by multiplying the surplus revenue value by the transform coefficient specified in field 551 . 1 , e.g. by the value of 0.50 following the example above. Budget items generated from this RIB rule 510 are stored in the expenditure budget at node A 1 , as defined in the destination field 560 . Exemplary RIB rules 520 , 530 are shown for various other nodes. Some may include reference revenue budget pointers and transform coefficients; others may not. [0037] In another embodiment, a reference revenue budget pointer 552 . 2 may include a scaling coefficient ( 552 . 2 A) identifying a scaling of the reference revenue budget pointer to be performed before thresholding. If a RIB rule defined a scaling coefficient of 0.9 and an applicable reference revenue budget value were $100,000, then Δbudget values would be awarded as soon as recorded revenue exceeded $90,000 (0.9*$100,000). Again, some RIB rule may include scaling coefficients but others need not, depending on the RIB rules established by the organization. [0038] In one embodiment, the destination field 560 of a rule may identify several destination addresses to which Δbudget may be applied, for example, identifying percentages for a distribution of the resulting budget increase. Rule 520 illustrates an example of this embodiment. [0039] In another embodiment, where the revenue database and expenditure budget database have identical data structures, it is permissible to omit the destination address field from the RIB rule set. In this embodiment, a source address field 540 may identify locations of revenue items that are operands to the RIB rule. The highest node identified in the source address field 540 also may be used as the destination address. Thus, for RIB rule 510 , node A 1 would be considered the highest node identified in the source address field 540 and would be used as an address in the expenditure budget data structure for storage of the new budget item. [0040] As noted, the foregoing embodiments may provide a software implemented EMA system. As such, these embodiments may be represented by program instructions that are to be executed by a server or other common computing platform. One such platform 600 is illustrated in the simplified block diagram of FIG. 6 . There, the platform 600 is shown as being populated by a processor 610 , a memory system 620 and an input/output (I/O) unit 630 . The processor 610 may be any of a plurality of conventional processing systems, including microprocessors, digital signal processors and field programmable logic arrays. In some applications, it may be advantageous to provide multiple processors (not shown) in the platform 600 . The processor(s) 610 execute program instructions stored in the memory system. The memory system 620 may include any combination of conventional memory circuits, including electrical, magnetic or optical memory systems. As shown in FIG. 6 , the memory system may include read only memories 622 , random access memories 624 and bulk storage 626 . The memory system not only stores the program instructions representing the various methods described herein but also can store the data items on which these methods operate. The I/O unit 630 would permit communication with external devices, such as the communication network ( FIG. 1 ) and other components. [0041] Several embodiments of the present invention are specifically illustrated and described herein. However, it will be appreciated that modifications and variations of the present invention are covered by the above teachings and within the purview of the appended claims without departing from the spirit and intended scope of the invention.

Enterprise management applications perform a “revenues increasing the budget” (RIB) operation on general ledger data and store elements of the general ledger data that have a RIB effect in another ledger, called the “RIB ledger”. RIB ledgers may include sets of RIB rules, storage for documents reflecting all relevant delta values together with the corresponding links to the underlying original transaction documents as well as storage for all relevant aggregated data. Accordingly, when audit operations are performed for RIB budget increases, relevant transaction data is readily available in the RIB ledger. Such copies of the data are more easily accessed than through a search of the larger set of general ledger data, thus facilitating and accelerating use of the RIB techniques in an online system.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for the control of venetian blinds, and in particular, venetian blinds in buildings which have windows and are used for industrial or commercial purposes, as well as to a control device incorporating a light sensor, such as a photodetector or a light-sensitive cell, for controlling raising and lowering of such venetian blinds as well as for varying the screening angle of the slats of such venetian blinds. 2. The Prior Art In the case of modern office buildings, providing protection from the sun's rays is important in preventing excessive heating of the work areas within the buildings, in saving energy in situations wherein air conditioning installations are employed and in providing display-quality worksites that are protected from glare. Up to now it has been customary to control the venetian blinds of the facade wall of an office building by means of sensors installed centrally on the roof of the building. Such an approach has the disadvantage that at any time according to the prevailing conditions, some windows of a facade wall are, under certain circumstances, completely protected from sunlight while other windows of the same facade wall lie in the shadow of other buildings or other parts of the same building. The problem of the different light exposure experienced by different windows of a facade wall is made even more difficult by virtue of the fact that the situation changes with the movement of the sun during the course of a day and according to the time of year. More recently, centrally controlled sun protection installations have been provided in an attempt to improve the operation of the automatic control systems for the venetian blinds. These installations use costly shading arrangement diagrams and astronomical clocks. However, such installations do not overcome the basic drawback of prior installations, viz., that the special proportions and relationships of the lighting provided at any one window are not taken in account. One further problem of centrally controlled venetian blinds is that, following the triggering of the lowering movement of the blinds in response to sensing a preselected background brightness, the lowering command for all of the venetian blinds remains in effect only during a predetermined time period, and following this predetermined blind lowering time period, a signal is generated which provides for opening of the blinds. It will be appreciated that if blinds of different lengths (heights) are located on a building facade wall, the lowering time of the longest blind must usually be adjusted and thus the rooms with shorter lowering times, will, as a result, remain darkened for an unnecessary length of time, before the opening control pulse is generated. The opening or screening angle of the slats which is set thereafter can thus be completely incorrect depending on the time of day and time of year and the particular position of a window. SUMMARY OF THE INVENTION An object of the invention is therefore to provide a method and a suitable control arrangement or system for carrying out this method, whereby, particularly in buildings wherein the different window surfaces in a facade wall are exposed to different degrees of lighting, the rooms of the building are shielded or shaded from the light in as uniform a manner as possible. To this end, according to the invention, the slats at least of one venetian blind are controlled such that the setting of the slats of the venetian blind in the screening angle providing the desired amount of opening of the blind is determined by a photodetector which detects the incident or impact angle of the rays of the sun. A novel control method in accordance with invention is applicable to a central control system or unit which controls a constant hypothetical image of a facade wall and cooperates with a wind sensor, in a known manner, in order to provide raising of the venetian blinds when the sensor detects a wind velocity exceeding a predetermined level. The method according to the invention has no effect on this primary purpose of such a central control unit but, in an advantageous manner, supplements this purpose by providing independent regulation of the light admitting (screening) setting of the blinds. The method of the invention is applicable to venetian blinds with horizontal slats and also to venetian blinds with vertical slats (vertical blinds). As a result of the independent control of the individual venetian blind provided, optimum control of the screening angle can be effected immediately after lowering of a blind has been accomplished, without having to take into consideration (as is the case with prior art systems) that longer blinds on the same facade wall will require a longer time to be lowered and only after these blinds are lowered are they able to be adjusted with respect to the screening angle of the slats. It is to be understood that, according to the invention not only can the venetian blinds of a facade wall be centrally controlled in a conventional manner to move up and down, but also, in response to an excessive or limited change within certain limited values of background brightness, any individual venetian blind can be individually lowered or raised. It is particularly important that the screening angle of the slats of the venetian blind be adapted to the changing position of the sun. In order to determine the angle of incidence or impact of the sun's rays, in accordance with a further preferred embodiment of the invention, the photodetectors of the central unit are pivoted in association with the venetian blind. Preferably, this is achieved in such a manner that when the sun is changing position the photodetectors follow the changing position of the sun. The movement of the photodetectors can thus be carried out under optimum conditions by suitable angular rotation of the slats. In accordance with a further aspect of the invention, the control device or system for carrying out the method of the invention includes a photodetector which is affixed to a slat of the venetian blind to be controlled, and which detects a predetermined amount or degree of deviation of the angle of the incidence or impact of the incident sun's rays from the normal angle on the associated surface area. It is noted that surface area as used here is understood as the maximum projection surface of a slat. Advantageously, the sun-tracking detector is used to determine the slightest deviations of the angle of incidence of sun's rays from the normal angle of incidence on the surface area of the slat and then to provide for modification of the screening angle in the direction in which the sun's rays continuously fall substantially vertically on the surface area of the slat. However, the invention can also be embodied such that a selected angle is continuously maintained between the incident sun's rays and the normal angle on the surface of the slat, in order to permit somewhat more light into a room than when the slats are aligned substantially vertical to the incident sun's rays. The compensating movements controlled by the control device in the latter embodiment serve to maintain the predetermined angle between the incident sun's rays and the surface area of the slat despite changing sun conditions. In a preferred, practical embodiment, the photodetectors comprise a pair of photodiodes arranged one behind the other in horizontally aligned relation in the direction of the sun's rays with a crosspiece or upstanding member projecting outwardly between them. With this arrangement, depending on the setting of the slat and the position of the sun, a shadow is cast on one or the other photodiode when the upstanding member is not disposed so as to be directly facing the sun. Alternatively, two photodiodes are arranged in a roof-shaped or V-shaped configuration in relation to the surface area of the slat, so that the control voltages produced by the photodiodes are the same only when both photodiodes receive the sun's rays at the same angle, i.e., only when the sun shines vertically on the surface area of the slat. As a consequence, the position of the sun can be determined at any time by simply pivoting the slat, and the slats can be adjusted so as to assume optimum screening angle. A control device according to a further important embodiment of the invention is improved by the addition of a further photodetector which is mounted adjacent to the blind and which, when a preselected background brightness is attained, produces a control pulse for controlling the operation of the venetian blind to, e.g., reduce the light level within the room in which the blind is installed by lowering the blind. The extra photodetector comprises a plurality of photodiodes (and preferably three photodiodes) which are directed skyward at different angles and which together pick up the incident light over a range of 180° in front of the venetian blind. It is pointed out that where control devices such as those of the embodiments discussed in the previous paragraph are used, it is possible to basically manage without a central control device. The lowering and raising of the venetian blind in such an embodiment is controlled by the additional photodetector responding to the relevant background brightness, and in the lowered state of the blind the sun tracking detector, mounted on a slat, is used to control the screening angle of the slat. However, as already described, cooperation with a central control device can also be very useful in order to, to the extent possible, maintain a uniform appearance over the facade wall and to protect the venetian blinds from wind damage. With such a combined control system, the lowering and raising of all of the venetian blinds of a facade wall is first of all centrally controlled and it is only when preselected limit values of the background lighting are exceeded, or are not reached, at particular individual windows, that the additional photodetectors which are mounted there are used to provide that the relevant venetian blinds are raised or lowered in accordance with the individual circumstance or situation. Other features and advantages of the invention will be set forth in, or will be apparent from, the detailed description of the preferred embodiment which follows. BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in greater detail relative to the exemplary embodiments represented in the drawings, wherein: FIG. 1 is a simplified side view of a venetian blind with associated photodetectors; FIG. 2 is a cross section through one slat of the venetian blind of FIG. 1 with a photodetector mounted thereon: FIGS. 3A, 3B and 3C are different views of a photodetector mounted adjacent to the venetian blind of FIG. 1 for the determination of background brightness. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, there is shown a section of a building wall 10 with a window 12 and a venetian blind 14 arranged outside the window 12. The venetian blind 14 is shown, for purposes of simplicity, both in the raised position thereof wherein the slats 18 of blind 14 are gathered together (at 14a) and in the lowered, light shielding or draped position (at 14b). In the raised position (14a), venetian blind 14 is received in a housing 16. The raising and lowering of venetian blind 14 as well as the rotation or turning of the slats 18 in the lowered position of blind 14 is carried out in a known manner by means of an electric motor 20 and a turning gear as is described, for example, in German Publication Opened to Public Inspection 36 25 365. It will be understood that the features of the invention described hereinafter are independent of the number, dimensions and sizes of the slats 18 as well as the manner of moving and guiding thereof. It is important only that the slats 18 in the lowered position of the blind 14 can be turned or rotated by means of controllable gearing, so that the slats 18 can be adjusted to different screening or shielding angles. As shown in FIG. 1, a photodetector 22 is mounted on one of the slats 18, and the photodetector 22 can be fixed in position dependent upon whether the sunlight, which is incident obliquely from above, impacts vertically on the surface area of the slats or incident or the impacting rays of the sun deviate in some other direction and at some other angle through the slats which differs from the normal impact angle on the surface area of the slats. A discussion follows hereinafter with respect to the basic construction of photodetector 22, with photodetector 22 being described in greater detail relative to FIGS. 2 and 3. Adjacent to venetian blind 14 is mounted another photodetector 24. Photodetector 24 can, for instance, be mounted in the wall adjacent to the window opening, on a guide for guiding the movement of slats 18 or in housing 16. This additional or extra photodetector 24 determines the background brightness and controls the lowering and raising of venetian blind 14. This operation is explained in greater detail relative to FIG. 4. In the embodiment of FIG. 2, photodetector 22 is inserted into a hole or perforation in a slat 18 preferably in the vicinity of the outside longitudinal edge of the slat 18. In this exemplary embodiment of FIG. 2, the photodetector 22 comprises two photodiodes 26 and 28 enclosed in transparent plastic (for instance, glass acrylate), and the photodiodes 22 are arranged at a predetermined gable angle relative to each other as in a gabled roof, i.e., are disposed in intersecting planes which form a predetermined angle therebetween. It is thus obvious that the control potential of the two photodiodes 26 and 28 is identical only when the two are subjected to sunlight of the same intensity and this is the case only when the rays of the sun are parallel to the line bisecting the gable angle of the mounting arrangement for photodiodes 26 and 28. If, on the other hand, the control potential (i.e., output voltage) of one of the two photodiodes 26 and 28 is different, e.g., lower, than that of the other one, it can be concluded that the rays of the sun are impacting or impinging at an acute angle relative to the aforementioned gable angle bisecting line. As a consequence, the photodiode 26 or 28 which produces the smaller control potential must be pivoted around in the direction of the other photodiode 28 or 26 in order to again attain a state of equilibrium in which the two photodiodes 26 and 28 are being uniformly radiated with light and, preferably, the surface areas of slats 18 which are guided parallel to them are aligned perpendicular to the impacting rays of the sun. Referring now to FIGS. 3A and 3B, the extra photodetector 24 which is used in the determination of the background brightness comprises, as shown in plan view in FIG. 3A, three photodiodes 34, 36 and 38 arranged adjacent to one another. The photodiodes 34, 36 and 38 are each directed at an intermediate angle of 60° skyward at different angles and thus, as shown in FIG. 3B, lie at an angle of 35° oblique to the vertical. Since, as shown in FIG. 3C, each of the photodiodes 34, 36 and 38 has a receiving area of approximately 60°, the photodiodes act together to detect the background brightness over the full angular range of 180° in front of the building facade wall. Referring again to FIG. 1, connection lines or wires 40 for photodetector 22 and connection lines or wires 42 for photodetector 24 are guided along the guide rails for the slats 18 of the venetian blind 14 to a distribution unit 44 installed either in, or on the top part of, a housing which is located at the top of blind 14 and which also houses motor 20. The distributor box 44 is connected by means of a socket coupling 43 to a motor control unit 46 which is installed in the building at a suitable site, preferably at not too great a distance from venetian blind 14. A conventional keying mechanism or keypad 48 is also connected to motor control unit 46 to enable independent operation thereof. This permits setting of the slats 18 of the venetian blind 14 manually in order, for instance, to darken one room for the purpose of showing a film. In such a case, to the motor control unit 46 is also connected an input connection 50 from a central control device (not shown). In the illustrated embodiment, a connection is provided in the form of a serial interface 50 for connection to a computer (not shown) and data storage (not shown) as well as a power supply source 52 for supplying motor 20 with 220 Volt operating voltage, and to the control device cooperating with photodetectors 22 and 24 and providing a control voltage of twenty-four volts. The motor control unit 46 is connected through a socket coupling 45 to motor 20 in order to control the motor 20 in accordance with different control inputs from motor control unit 46. The operation of the control system described above is as follows. It is assumed that in the initial stage thereof the venetian blind 14 is raised and the slats 18 of venetian blind 14 are thus gathered together at the top of blind 14 (as indicated in FIG. 1 at 14a). When a trigger signal is transmitted, either through connection 50 from the central control device mentioned above or from photodetector 24 when the background brightness exceeds a predetermined limit for effecting lowering of the venetian blind 14. As soon as the lowered position (indicated at 14b) has been reached, the screening angle of slats 18 is then detected and adjusted by means of photodetector 22, independently of whether the other venetian blinds of the same facade wall, which are lowered simultaneously, have or have not yet reached the lowered position thereof because of their longer length. The control of the screening angle of slats 18 by means of photodetector 22 is maintained in effect continuously thereafter and acts to modify the position of the slats corresponding to the changing position of the sun. This continuous control is provided until the venetian blind 14 is raised again in response to a raising signal transmitted from the central control device or from photodetector 24. The control device which has been described above as operating in cooperation with alignment-dependent photodetector 22 and with the other photodetector 24 used in detecting the background brightness, offers the capability that when a plurality of venetian blinds are in the lowered state (in which these blinds are normally controlled by means of the alignment-dependent photodetector 22), the blinds can be temporarily rotated to a horizontal slat setting by photodetector 24, when the blinds fall under the shadow of a cloud. With this approach, as soon as the cloud has passed and the background brightness increases once again, the alignment-dependent photodetector 2 will again take over control of the screening angle of the slats 18 and will provide for the adjustment of the slats out of a horizontal position into the optimum screening or adjustment setting corresponding to the position of the sun. The manual setting of the angle of the slats 18 by means of keying mechanism 48 can be integrated in such a manner into the above-described control system that automatic adjustment of the screening angle by means of photodetector 22 does not occur when the blind has been manually lowered by double operation of keying mechanism 48 and the slats 18 have been brought into closed position. The automatic control mechanism would thus be initiated based on the assumption that this control is provided to produce a deliberate darkening of the room as when, for instance, a room is darkened for a slide show lecture. On the contrary, if the blind had been lowered manually by a single operation of keying mechanism 48, the slats are set at a predetermined angle of, for instance, 38° and the optimum angle is then set after being determined by the sun-finding (sun-tracking) detector 22 only when a certain brightness is exceeded. Also, when the automatic sun-finding mechanism is manually engaged in the slat setting, following such an action, the automatic sun-finding detector is disconnected. The detector then returns to operation only when a raising movement is briefly activated and then is stopped. The control device according to the invention has been described above in connection with the control of a single venetian blind. However, it is to be understood that the invention can also be used when a plurality of windows of a facade wall are exposed at any time of year and time of day to basically the same amount or degree of light, and also when essentially the same lighting requirements apply to all of the associated rooms of the building. A single sun-finding detector 22 on one slat 18 of the venetian blinds, together with a single additional photodetector 24 disposed adjacent to one of the windows, are sufficient to control all of the venetian blinds which would then be connected essentially in parallel with one another and under the same control. In all cases, the transmission of measuring and control signals from photodetectors to motor control unit and from this unit to the motor can also be achieved without hard wired connections. Similarly a radio connection can be provided to the central control device. Communications through the sections 50 can also contain errors, and this arrangement facilitates identification and localization of such errors. Further, phototransistors can also be used in place of photodiodes. Thus, although the invention has been described with respect to exemplary embodiments thereof, it will be understood by those skilled in the art that variations and modifications can be effected in these exemplary embodiments without departing from the scope and spirit of the invention.

The lowering and raising of slats of a venetian blind are controlled by control signals from a photodetector circuit which is mounted adjacent to the venetian blind and which acts responsive to predetermined limit values of the background brightness being exceeded. Following lowering of the venetian blind, control of the closing or screening angle of the slats is provided by a sun-tracking photodetector affixed to a slat and operating in dependence upon the angular alignment of the slat. In order to fix the closing angle of the slats at a selected value, subsequent adjustment of the slats is controlled by the sun-tracking photodetector which can, in turn, be controlled externally by a manually operated keying mechanism. The photodetector used in measurement of background brightness comprises three aligned photodiodes which are directed skyward in three different directions and which together detect the incident light over the full range of 180° in front of the venetian blind.

RELATED APPLICATIONS The present application is a continuation-in-part of U.S. patent application serial No. 135,585, filed Dec. 21 1987, entitled "Apparatus of Glass Repairs." This said application is now abandoned. FIELD OF THE INVENTION The present invention relates to methods and apparatus for repairing glass and more particularly relates to improved techniques for in situ repairing of shatterproof windshields and the like. BACKGROUND OF THE INVENTION When glass, and more particularly, a windshield is struck by an object or projectile, such as a rock, the outer glass pane is likely to be damaged. As is well known in the prior art, a shatterproof windshield is composed of an intermediate plastic laminate which bonds an outer glass pane and an inner glass pane together. This combination of glass-plastic laminations absorbs the forces of impact, thereby reducing the extent of the damage to the windshield. Upon impact, glass on the surface of a windshield fractures into a simple crack, or a cone-like formation with damage directed radially therefrom in several directions. When a cone is formed, it normally has a peak on the surface which is often exposed to the atmosphere. The base of the cone typically extends to the bottom of the outer glass pane adjacent the plastic laminate. The sides of this cone, as well as any related fractures that may have formed, are visible to an observer looking through the windshield. Indeed, as light is transmitted through these new interfaces that have formed within the glass, extraneous refraction thereof occurs. The damage to the windshield, conventionally categorized as a simple crack, a bull's-eye, a star, or a combination thereof, is typically small and confined to the outside glass layer. In the case of bull's-eyes, the fracture planes usually run parallel to the glass surface, sloping downwards. The presence of these fracture planes, which may cover a significant portion of the windshield, can be distracting to the driver and interfere with his line of vision. Furthermore, the presence of fractures, showing as cracks, constitute points of weakness within the outer glass pane. As is well known to those skilled in the art, such cracks are apt to propagate further, resulting in substantial interference with the driver's vision. Accordingly, to avoid a collision caused by such visual distractions and inhibited line of sight, expensive replacement of the windshield is required. On the other hand, if this damaged glass could have been repaired prior to the propagation of the cracks, by filling the voids within the said damage whereby the fracture planes were properly bonded together, such conventional and costly replacement of the windshield could be avoided. As is also well known in the prior art, through the use of resins which have refractive indexes substantially the same as that of glass, suitable viscosity, suitable adhesion to glass, and are non-yellowing, it is possible to repair damaged glass and accordingly extend a windshield's life. Thus, if such resin is injected properly into the damaged glass by one skilled in the art, the interfaces hereinbefore described may be rendered invisible. If such a resin has been applied improperly, however, the damage will still be visible, showing voids, and, of course, have fracture planes that are not bonded together, thereby resulting in cracked glass which is apt to continue to fail. It is well known to those skilled in the prior art, that filling voids in star damages is difficult, not only because the ends of the star are often far from the point of impact, but also because the passages between the fractured planes are narrow. This damage configuration tends to inhibit or even preclude the flow of a properly injected resin into the damage area. An alternative method to repair such star damage is to drill holes at these points, to allow for the injection and consequent flow of resin into these locations. Capillary action will then pull the resin into the cracks until opposed by frictional forces. As is known to those skilled in the art, thinning the resin helps delay the affect of these frictional forces upon such capillary action, but this typically causes weak repairs. Accordingly, the repair is ephemeral and only cosmetic. Many attempts have been made throughout the industry to develop methods and apparatus to enable resin to effectively and reliably penetrate into all voids contained in damaged windshields. Besides drilling holes in the outer glass pane to promote resin flow, the prior art teaches several methods of evacuating air from the damaged area, followed by injecting the resin into the voids, under pressure. Another method known to those skilled in the prior art involves cycles of evacuating and pressurizing. As will become apparent, those skilled in the windshield repair art have attempted to overcome these and other difficulties associated with filling these voids in damaged windshields. For example, in U.S. Pat. No. 4,597,727, Birkhauser discloses a windshield repair kit which applies a vacuum followed by a pressure cycle to force resin into the voids constituting the damaged area. While the air-evacuation method taught by Birkhauser may be advantageous to repair some damages, it should be apparent that creating a vacuum for each repair is time-consuming and expensive. It should be clear to those knowledgeable in the art that a repair method using external pressure to cause the penetration of resin into damaged areas, can be advantageous provided an equivalent force is applied on the exterior of the glass surface in an inwards direction against the curvature of the windshield. If this equilibrium is not achieved and maintained during the repair the widening of cracks and the like due to such pressure may cause further failure of the windshield. In U.S. Pat. No. 3,562,366, Sohl discloses a method of repairing windshields which uses ultrasonic vibration to make the flow of resin into the voids possible. Werner, in U.S. Pat. No. 3,993,520, discloses a pressure-method followed with vacuum cycles to promote flow of the resin if difficulties are encountered therewith. The Werner windshield repair apparatus consists of a bridge-like member interconnected with two suction cups, which attach to the glass surface. Leveling screws are used to provide support on the opposite side of the injection assembly, in order for it to be in contact with the glass. When resin is added to the Werner apparatus, pressure is applied, which radiates in all directions. Sideways, the resin is trying to force its way between the seal and the glass surface. However, the same forces provide an uplift on the injection assembly, causing it to move away from the damage. This uplifting action is transmitted to the bridge-like member and suction cups, whereby the bridge is caused to be tilted because of the pivoting effect created where the bridge attaches to the top of the suction cups. As should be apparent, the seal will then become misaligned with the glass surface and the resin will then spill to the outside of the injector. Once this happens, of course, less resin is present in the injection chamber and the necessary pressure is difficult to re-establish. Accordingly, it should be clear to those skilled in the art that Werner apparatus and method are limited to small damages primarily because it inherently fails to adhere to the glass surface. Thus, while this pressurized injection method has improved the windshield repair art, the problem of how to inexpensively and reliably sustain sufficient downward pressure to secure uninterrupted contact between the seal and the damage has heretofore been unsolved. As is well known to those familiar with this injection method, filling resin with conventional droppers tends to cause the resin to travel down the inside wall of the injector barrel, thereby coating the threads thereof. Additionally, the vacuum created by unscrewing the injector pin is inadequate to provide the forces to enable trapped air to be expelled from the damage. Since the fracture planes engendered by the cone-shaped damage hereinbefore described are usually sloped relative to the glass surface, such release of the pressure imparted by the injector pin tends to cause air occasionally to float from the damage into the injector. The pressurized repair techniques known to the prior art are thus limited to repairing relatively small damaged areas, typically in the range of one to one and one-half inches in diameter. As has been explained herein, the voids in windshield damage have narrow passages, and accordingly require high pressures to force resin therein. The repair devices known in the prior art have had limited success providing these prerequisite pressures. Accordingly, these limitations and disadvantages of the prior art are overcome with the present invention, and improved repair means and techniques are provided which effectively and reliably repair damaged windshields. SUMMARY OF THE INVENTION In a preferred embodiment of the present invention, an apparatus for making in situ repairs with liquid resin to damage at or near the surface of shatterproof windshields is provided. More particularly, means is provided to conveniently and effectively attach to a windshield, a device within the concept of the present invention, whereby such a device is held to the surface and, using advantageous leveraged forces, promotes the resin penetrating cracks in the windshield and the like. Referring now to the improved repair apparatus, it includes a plate disposed on the top portion of a preferably rectangular housing which supports a novel injector assembly and pressure assembly. The housing includes two pair of substantially vertical walls. The support plate is pivotally interconnected to the top of the housing by a pair of hinges, one disposed on each of its longitudinal sides. The housing is secured to the surface of the windshield by the cooperative action of a membrane and handlebar commonly used to secure a pencil sharpener to a table surface. The vacuum created thereby is maintained by the solid housing structure. The injector assembly is disposed perpendicularly of and axially through one of three threaded apertures which look like ears, and which are disposed on one end of the support plate. Adjustment screws which are disposed on the other end of the support plate control the pitch and elevation of the injector assembly with respect to the surface damage. These adjustments enable the prerequisite pressure to be maintained upon the resin contained in the injector barrel, which, of course, enables the resin to penetrate into the damaged portion of the windshield. Thus, the preferred embodiment is firmly held to the glass surface, thereby enabling maximum pressure to be exerted upon the injector assembly. It is an important feature of the present invention that the holding power of the injector assembly derives from the leverage action provided by the support plate in cooperation with the hereinbefore described hinges. It is also a feature of the present invention that the preferred embodiment is easily made parallel to the damaged surface by manipulating the adjustment screws thereof. The pressure assembly, disposed medially of the hinge connection and the plurality of ears, includes a guide pin and a pressure arm. The pressure arm is concentrically attached to the guide pin which is threadingly attached perpendicularly to the top of the support plate. To maintain pressure upon the injector assembly, the pressure-arm is rotated on top of the plunger contained in the injector barrel and then driven downwardly by tightening an adjustment knob thereon. The preferred embodiment enables simple cracks to be repaired by inserting the plunger into the injector barrel and applying hand-pressure thereon. For star cracks and the like, however, the pressure assembly is invoked as hereinbefore described to provide greater pressure upon the seal-damage interface. While the preferred embodiment may be applied on most portions of a windshield, an extension assembly is provided to accommodate portions of a windshield with substantial curvature or to portions thereof proximal to corners. This extension assembly includes a variable-length plate into which may be perpendicularly attached an injector assembly. Also included on the extension assembly is a suction cup to secure it to these adverse portions of the windshield. The adjustment screws contained on the plate portion of the housing may, of course, be adjusted to take advantage of the leveraged forces even on this remote assembly. Accordingly, it is an object of the present invention to provide a windshield repair apparatus which may be installed with minimal effort on virtually any portion of the surface of a windshield. It is still another object of this invention to provide a windshield repair apparatus which establishes a secure hold on virtually any portion of the surface of a windshield. It is another object of the present invention to provide a windshield repair apparatus which may be accurately disposed parallel of the surface of a windshield. It is yet another object of the present invention to provide a windshield repair apparatus with means to effectively position an injector assembly on virtually any portion of the surface of a windshield. It is another object of the present invention to provide a windshield repair apparatus with means to provide constant and sufficient pressure on a resin-damage interface on virtually any portion of the surface of a windshield. It is another object of the present invention to provide a windshield repair apparatus with means to apply and maintain sufficient pressure to the seal-damage interface whereby regular cracks of up to 2 1/2 inches in radius, and star cracks of up to 1 1/2 inches in radius, may be effectively repaired. It is still another object of the present invention to provide a windshield repair apparatus with means to prolong the pressure applied to a seal-damage interface without a worker being present. It is yet another object of the present invention to provide a windshield repair apparatus with means to enable a worker to repair more than one windshield contemporaneously. It is a specific object of the present invention to provide an apparatus to make in situ repairs with liquid resin to damage at or proximal to the surface of a shatterproof windshield, comprising securing means for releasably attaching said apparatus to said windshield surface, an injector assembly for transporting said resin to said damage, a pressure assembly for regulating and maintaining the pressure exerted upon said resin, adapting means pivotally interconnecting said injector assembly and said pressure assembly with said securing means, housing means fixedly interconnecting said securing means and said adapting means, said adapting means having first support means disposed at one end portion thereof to receive said injector assembly, having second support means disposed medially thereof to receive said injector assembly, and having control means disposed at the other opposite end portion thereof to control the disposition of said injector assembly with respect to said damage, said securing means including a substantially flat membrane comprising the bottom portion of said housing means and adapted to engage said windshield surface by creating a vacuum within said housing means, said support means including a first plurality of receiving means in which said injector assembly is threadingly interconnected with one of said receiving means, said injector assembly disposed substantially perpendicularly of one of said first plurality of receiving means, and comprising a substantially cylindrical barrel disposed longitudinally of said injector assembly, and axially containing a plunger with a piston fixedly attached at one end of said plunger, said barrel including about a two percent gradual taper from its top portion to its bottom portion to urge said resin therethrough, and adapted to receive and transport said resin to said damage, said pressure assembly comprising a guide pin disposed perpendicularly of said support means, an arm means rotatably and concentrically interconnected with said guide pin, to enable said pressure assembly to cooperate with said injector assembly to maintain a substantially constant force upon said resin, and including adjusting means to regulate the pressure exerted upon said arm means, said housing means including two pair of corresponding rigid substantially vertical walls configured to form a substantially rectangular cross-section, said adapting means including an extension assembly slidably interconnected with said housing means for reaching damage disposed in portions of said windshield with substantial curvature or proximal to corners thereof, said extension means comprising a plate means and a corresponding channel means, with said plate means being slidably inserted into said channel means, said extension plate means including a second plurality of receiving means in which said injector assembly is threadily interconnected with one of said receiving means, and including suction cup means to releasably attach said extension assembly to said portions of said windshield with substantial curvature or proximal to corners thereof. These and other objects and features of the present invention will become apparent from the following detailed description, wherein reference is made to the figures in the accompanying drawings. IN THE DRAWINGS FIG. 1 is a perspective view of an apparatus embodying the concepts of the present invention. FIG. 2 is a top plan perspective view of the structures depicted in FIG. 1. FIG. 3 is a cross-sectional view of the structures depicted in FIGS. 1 and 2, along longitudinal axis 3--3. FIG. 4 is a cross-sectional view of the structures depicted in FIGS. 1 and 2, along transverse axis 4--4. FIG. 5 is a perspective view in partial cross-section of another apparatus embodying the concepts of the present invention. FIG. 6 is a top plan view of another apparatus embodying the concepts of the present invention. FIG. 7 is an enlarged sectional view of a portion of the structures depicted in FIG. 5. FIG. 8 is a cross-sectional view of another apparatus embodying the concepts of the present invention. DETAILED DESCRIPTION Referring now to FIG. 1, there may be seen a perspective view of a windshield repair apparatus 20 embodying the concepts of the present invention. Support plate 46 supports injector assembly 126, pressure assembly 138, and adjusting screw 56, and is secured to housing 38 by two hold-down screws 50a and 50bwith springs 52a and 52b, respectively. Housing 38 may be constructed from die-cast aluminum and the like. Hold-down screws 50a and 50b, and adjusting screw 56 are supported on one end of plate 46, and injector assembly 126 is disposed perpendicularly of plate 46 on the other opposite end thereof. More particularly, injector assembly 126 is disposed perpendicularly of and axially through one of three threaded apertures 60a, 60b or 60c centrally disposed in ears 124a, 124b 124c, respectively. For example, as depicted in FIG. 1, injector assembly is screwed into aperture 60b contained within ear 124b until shoulder 129 is reached. Still referring to FIG. 1, guide pin 140 of pressure assembly 138 is perpendicularly and fixedly attached to plate 46 at threaded aperture 139 (depicted in FIG. 6). Adjusting knob 147 and nut 146 with spring 144, and guide 148 are rotatably and concentrically attached to guide pin 140. Pressure arm 150 is rotatably attached to guide pin 140 and disposed parallel to plate 46. Plunger 134, disposed axially inside injector barrel 128, is abutted on its top portion by pressure arm 150. As is well known in the pencil sharpener art, membrane 22 and cylindrical handlebar 30 cooperate to releasably attach the windshield repair apparatus 20 to a glass surface and the like. As depicted in FIGS. 2, membrane 22 has ribs 24 on its interior surface to impart strength thereto. Now referring to FIGS. 3 and 4, clip 26 is molded into the top surface of membrane 22. Said clip 26 has elongated hole 28 (depicted in FIG. 3) in which handlebar 30 can slide longitudinally of plate 46. Said handlebar 30 has a protective cap 32 at on end, lock-washer 34 at the other end, and offset 36 where the handlebar passes through clip 26. Handlebar 30 is connected to housing 38 through two holes 40 disposed in its sides. Lock-washer 34 anchors said handlebar to housing 38. Said housing 38 has guide 42 for clip 26. As depicted in FIG. 3, windshield repair apparatus 20 is placed upon the surface of windshield 69, with membrane 22 substantially parallel thereto and with the bottom portion of injector barrel 128 centered over cone 76. Cone 76 is the visible manifestation of damage to the outer glass layer 70 of windshield 69. Handlebar 30 is then rotated through a 180 degree arc whereby offset 36 causes a lifting of clip 26 which is communicated to membrane 22. This lifting action upon membrane 22 creates a vacuum holding housing 38 firmly against the adjacent surface of windshield 69. Accordingly, injector barrel 128 is fixedly held over cone 76. Now referring to FIG. 1, support plate 46, which is mounted to the top of housing 38, is held in place with hinges 47a and 47b. Hinges and 47a and 47b are bolted to housing 38 at recesses 45a and 45b (depicted in FIG. 2), respectively. Adjusting screw 56 enables housing 38 to be elevated from a disposition parallel to the surface of windshield 69, whereby injector assembly 126, disposed at the other opposite end of plate 46 from screw 56, is correspondingly tilted downwards by pivoting about an axis defined by hinges 45a-45b. Accordingly, annular seal 132, disposed on the bottom portion of injector barrel 128, securely circumscribes and abuts against the windshield surface encompassing cone 76. It is an advantage of the present invention that the holding power of injector assembly 126 derives from the leverage action provided by plate 46 in cooperation with hinges 45a and 45b. Additionally, the structures of the present invention enable seal 132 to be conveniently disposed parallel to outer surface 70 of windshield 69. More particularly, when preferred embodiment 20 is placed on outer surface 70 as hereinbefore described in detail, the space created between the bottom edge of seal 132 and said surface may be used to visually guide the adjustments to screw 56 whereby seal 132 is rendered parallel to this surface. As has also been hereinbefore described, adjustment screw 56 may be further rotated to cause an increase in the pressure upon injector assembly 126, in turn, deflecting the pressured-glass at cone 76 toward the interface between outer layer 70 and plastic laminate 72, causing other damage, if any, in the vicinity of cone 76 to become visible. As is known to those skilled in the art, such ancillary damage often goes undetected, resulting in an incomplete repair and an unsatisfied customer. Referring now to FIG. 3, there may be seen a longitudinal cross-sectional view of the windshield repair apparatus 20 depicted in FIGS. 1 and 2. Pressure assembly 138 is disposed perpendicularly of plate 46 and secured thereto through aperture 139 by lock nut 142. Guide 148 is disposed concentrically of guide pin 140 and is rotatably attached thereto. Pressure arm 150 is fixedly attached to guide 148. When pressure arm 150 is rotatably disposed concentrically upon piston 134, its position is secured by tightening nut 146 against the resistance provided by spring 144. By placing a palm of the hand upon knob 147, a worker may easily cause pressure arm 150 to be lifted notwithstanding the said resistance afforded by spring 144. In accordance with the concepts of the present invention, pressure assembly 138 overcomes several problems associated with providing sufficient pressure to enable conventionally used acrylic, urethane and epoxy resins to thoroughly penetrate into a damaged area in the outer layer of a windshield. As should be apparent to those skilled in the art pressure arm 150 provides constant downward force upon piston 134, which is propagated to the interface of seal 132 and cone 76. Additionally, this pressure may be maintained for a prolonged period of time without a worker being present. This, of course, affords the opportunity for a worker to repair more than one windshield contemporaneously. It should be apparent that this method is superior to that commonly used in the prior art, whereby a worker typically rotates the conventional screw-type injector about 1/8 revolution about every 10 seconds to maintain pressure on the seal. It is also a feature of the preferred embodiment that the pressure upon the seal-cone interface may be gradually increased by rotating adjusting nut 146. Still referring to FIG. 3, to repair cone 76, a small amount of resin 94, preferably about 0.2 cc or about 10-12 drops, is injected with a syringe or a dropper into sleeve 130 of injector barrel 128. Plunger 134 with piston 136 fixedly attached is then inserted into sleeve 130. To squeeze piston 136 as it travels down injector barrel 128, sleeve 130 is provided with a slight taper preferably about 2%. When the windshield damage is minimal, as is the case typically with bull's-eyes, repair thereto may be accomplished with the preferred embodiment by applying modest pressure only with plunger 134. On the other hand, when the damage is more severe, as is the case typically with star cracks, repair thereto requires additional pressure which is advantageously provided by pressure assembly 138. As hereinbefore described, pressure arm 150 is mounted with guide 148 concentrically upon guide pin 140. Tightening nut 146 compresses spring 144 which, in turn, exerts increased pressure upon resin 94. This pressure is maintained constant as resin 94 enters and penetrates the damage. It should be apparent to those skilled in the windshield repair art that the preferred embodiment of the present invention overcomes the limited holding power provided by suction cups and the like. For example, increasing the pressure in a conventional repair apparatus consisting essentially of an injector traversing a bridge-like span supported by a pair of suction cups, tends to drive such suction cups away from the windshield surface. This, of course, destroys the integrity of the seal between the damage and the glass surface. On the other hand, as hereinbefore described in detail, the preferred embodiment affords a holding power heretofore unknown to the prior art via the novel cooperation between membrane 22, handlebar 30, clip 26 and offset 36 to effect the creation of a vacuum between the bottom of membrane 22 and the surface 70 of windshield 69, and the maintenance thereof via the solid walls of housing 38. This holding power is advantageously reinforced by the stability and strength provided by pivotally modifying the disposition of injector assembly 126 with respect to the damage, by manipulating adjusting screw 56. Thus, the present invention provides a significant improvement in the holding power as well as in the application of pressure to damage over conventional windshield repair methods. As is well known in the prior art, in situ repair of windshields has been limited to damage radii of no larger than 1 to 1.5 inches. Similarly, the windshield repair devices and techniques taught by the prior art have had only limited effectiveness in cases where the ends of a star crack are extremely narrow. The preferred embodiment of the present invention solves these limitations and disadvantages of the prior art by enabling the pressure applied to the seal-glass interface to be conveniently and effectively increased and sustained. More particularly, in cases where increased pressure is required to accomplish a repair, screw 56 is adjusted so that plate 46 is leveraged about pivoting axis 45a-b causing increased pressure upon seal 132. As has been hereinbefore described in detail, pressure assembly 138 may also be invoked to increase the pressure still further. Moreover, the pressure upon seal 132 is maintained constant by the hereinbefore described cooperation between pressure arm 150 and plunger 134. As is conventional in the art, the pit left in the surface of the windshield, after the repair is completed may be filled with a fast-curing resin. It is within the concept of the present invention to adapt the structures hereinbefore described in detail whereby repairs may be conveniently made to portions of a windshield with substantial curvature or to portions of a windshield proximal to corners. One such embodiment of the present invention is depicted in FIGS. 5 and 6. Specifically referring to FIG. 5, remote adapter assembly 152 is releasably attached to plate 46 with hold-down screw 162. A variable-length remote assembly 152 is achieved by the cooperation of extension plate 166 and channel 154 with slot 156. More particularly, the extension prerequisite to disposing injector assembly 126 over the damage as hereinbefore described in detail, is accomplished by sliding solid extension plate 166 into channel 156 and securing the length thereof by tightening screws 168a and 168b. Suction cup 170 is attached to extension plate 166 with stem 172 in conjunction with the combination of adjuster nut 178, spring 176 and washer 174. When injector assembly 126 is properly positioned over the damage, suction cup 170 is pressed upon the surface of the windshield, screw 158 and nut 178 are simultaneously adjusted until seal 132 is disposed parallel to the damaged surface. Injector assembly 126 is then screwingly abutted against the surface below. Again invoking the unique leverage feature of the present invention, screw 158 and nut 161 may be simultaneously adjusted to provide the leverage necessary to exert the pressure required to force the resin into the damage. As should be clear to those skilled in the art, even more pressure may be exerted upon seal 132 by rotating adjusting nut 178, increasing the holding power of suction cup 170 upon the proximal glass surface therebelow. Referring to FIGS. 5 and 7, there may be seen a modified pressure assembly 180 which is superimposed upon injector assembly 126. Dome 186 of pressure assembly 180 is preferably constructed of clear plastic material to enable spring 182 and plunger 134 to be seen. Constant pressure upon the resin may be conveniently provided by rotating adjuster screw 184. FIG. 6 depicts a top planar view of the coordination of remote arm assembly 152 with the preferred embodiment of the windshield repair apparatus 20. Support bar 154 is attached to plate 46 by hold-down bolt 162 being secured to either of threaded aperture 165a or 165b. More particularly, as depicted in FIG. 1, apertures 165a and 165b are provided to enable remote assembly 152 to be attached to either longitudinal side portion of housing 38. This feature, of course, affords the maximum reach of embodiments of the present invention. Plate 166 provides three locations, 60d, 60e or 60f at which to support injector assembly 126 perpendicularly thereof, as hereinbefore described in detail. Ears 167a and 167b are provided to enable repairs to be made to the remotest corners of the windshield and the like. Aperture 60e is centrally disposed within ear 167a and aperture 60f is centrally disposed within ear 167b. To repair damage remote from flat portions of the windshield but not necessarily in corners thereof, aperture 60d is provided on plate 166. As should be clear to those skilled in the art, the advantageous features of the present invention significantly broadens the applicability of in situ windshield repair methodology. Indeed, embodiments of the present invention overcome the limitations of the prior art regarding the size and extent of windshield damage which may be repaired in situ. More particularly, the present invention affords the capability to repair regular cracks up to 21/2 inches in radius, i.e., cracks up to 5 inches is diameter; and star cracks up to 11/2 inches in radius, i.e., with a coverage of up to 3 inches. FIG. 8 depicts a cross-sectional view of a portion of an embodiment of the present invention adapted to repair a large surface damage 196. Rigid collar 192 and large diameter seal 194 are placed below shoulder 129 of injector barrel 128 to enable seal 132 to encompass damaged area 196 on the surface of glass layer 70. Also depicted is adapter fitting 188 and 0-ring 190 attached to injector assembly 126 to accommodate an external vacuum source and the like. Other variations and modifications will, of course, become apparent from a consideration of the structures and techniques hereinbefore described and depicted. Accordingly, it should be clearly understood that the present invention is not intended to be limited by the particular structures and methods hereinbefore described and depicted in the accompanying drawings, but that the concept of the present invention is to be measured by the scope of the claims herein.

Means and methods are provided for the in situ repair with liquid resin of shatterproof windshields and the like. An apparatus is provided which is composed of a plate disposed at the top portion of a preferably rectangular housing which supports a novel injector assembly and pressure assembly. The support plate is pivotally interconnected to the top portion of the housing preferably by a pair of hinges disposed on each of the housing's longitudinal sides. The housing is secured to the surface of the windshield by a vacuum created by the action of a membrane-handlebar assembly. The injector assembly is disposed perpendicularly of and axially through one of a plurality of ear-like apertures. The apparatus is adapted to enable convenient adjustments to the pitch and elevation of the injector assembly with respect to the surface damage, accordingly provide a means and method to maintain the requisite pressures upon the liquid resin as it is transported through the injector assembly to the seal-damage interface. The holding power of the injector assembly derives from the leverage action inherent in the concept of the present invention.

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. application Ser. No. 14/013,066, filed Aug. 29, 2013, now U.S. Pat. No. 8,967,817, which is a continuation of U.S. application Ser. No. 13/481,431, filed May 25, 2012, now U.S. Pat. No. 8,810,903, which is a continuation of U.S. application Ser. No. 13/205,278, filed Aug. 8, 2011, now U.S. Pat. No. 8,208,200, which is a continuation of U.S. application Ser. No. 11/971,640, now U.S. Pat. No. 8,018,650, filed Jan. 9, 2008, which claims priority under 35 U.S.C. §119(e)(1) to U.S. Ser. No. 60/885,261, filed Jan. 17, 2007, which claims priority under 35 U.S.C. §119 to German patent application serial number 10 2007 003 305.4, filed Jan. 17, 2007. These applications are incorporated herein by reference in their entirety. FIELD The disclosure generally relates to imaging optical systems that include a plurality of mirrors, which image an object field lying in an object plane in an image field lying in an image plane, where at least one of the mirrors has a through-hole for imaging light to pass through. The disclosure also generally relates to projection exposure installations that include such imaging optical systems, methods of using such projection exposure installations, and components made by such methods. BACKGROUND Imaging optical systems are known as projection optical systems as a component of projection exposure installations for microlithography. Imaging optical systems are also known in conjunction with microscope lenses for inspecting masks or wafers. SUMMARY In one aspect, the disclosure features an imaging optical system that includes a plurality of mirrors configured to image an object field lying in an object plane in an image field lying in an image plane. At least one of the mirrors has a through-hole configured so that imaging light can pass therethrough. A reflection surface of at least one mirror is in the form of a free-form surface which cannot be described by a rotationally symmetrical function. In another aspect, the disclosure provides a projection exposure installation that includes an imaging optical system as described in the preceding paragraph, and a lens system configured to direct illumination light to the object field of the imaging optical system. The projection exposure installation is a projection exposure installation for microlithography. In a further aspect, the disclosure provides a method that includes using the projection exposure installation described in the preceding paragraph to produce a microstructure on a wafer. In some embodiments, the disclosure provides an imaging optical system wherein a reflection surface of at least one mirror is in the form of a free-form surface which cannot be described by a rorationally symmetrical function. It has been recognized that using free-form surfaces instead of reflection surfaces having a rotationally symmetrical axis provides a new level of design freedom which results in imaging optical systems with combinations of properties which are not possible with rotationally symmetrical reflection surfaces. The free-form surface cannot be described by a function which is rotationally symmetrical about a marked axis representing a normal axis to a surface portion of the optical surface. The free-form surface thus cannot be defined in particular by a conic section-aspheric equation. Aspheres of this conic type deviate from spherical symmetry but can be described, however, by a rotationally symmetrical function, namely a function which is dependent on only one parameter, namely the distance to an optical axis, whereas the free-form surfaces require at least two parameters which are independent of one another to describe the surface. Conic section-aspheric surfaces are therefore not free-form surfaces. The shape of a boundary of the optically effective surface is not significant. Optically effective surfaces which are not bounded in a rotationally symmetrical manner are known. Optically effective surfaces of this type can nevertheless be described by a rotationally symmetrical function, a non-rotationally-symmetrically bounded portion of this optical surface being used. The free-form surface may be a static free-form surface. The term “static free-form surface” refers to a free-form surface, the shape of which is not actively modified during use of projection in the projection optical system. A static free-form surface can of course be displaced for adjustment purposes. The free-form surface can, in particular, be constructed on the basis of a planar reference surface or basic shape, a concave reference surface or a convex reference surface. In particular, at least one free-form surface may be used which is constructed on the basis of a curved reference surface. In this case, a reference surface with a vertex curvature which is constant over the entire reference surface can be used. A conic section-asphere may also be used as a reference surface. In conventional imaging optical systems including a through-hole, which are known as pupil-obscured systems, the use of this type of free-form surfaces can enable compact imaging optical systems with a low level of imaging errors to be achieved and, in particular, a high light throughput to be produced. According to the number of mirrors in the imaging optical system, a single mirror, or a plurality of mirrors, or all of the mirrors of the imaging optical system may be in the form of free-form surfaces. The free-form surfaces can have a maximum deviation from a rotationally symmetrical surface, which is best-fitted on the free-form surface and which does not necessarily match a designed reference surface, of at least the value of the wavelength of the imaging light. The deviation of, in particular, at least the value of a wavelength of the imaging light is, in practice, always markedly greater than the manufacturing tolerances during production of optical components for microlithography which, in absolute terms, are conventionally 0.1 nm and, in relative terms, are conventionally 1/50 or 1/100 of the wavelength of the illumination light used. In the case of illumination with EUV wavelengths, the deviation is at least several tens of nm, for example 50 nm. Larger deviations, for example 100 nm, 500 nm or 1,000 nm or even larger deviations are also possible. When using systems with imaging light of higher wavelengths, even greater deviations are possible. A free-form surface may be provided, for example, by a biconical surface, i.e. an optical surface with two different basic curves and two different conical constants in two directions perpendicular to one another, by a toric surface or an anamorphic and, at the same time, in particular, aspheric surface. A cylindrical surface therefore also represents a free-form surface of this type. The free-form surfaces may be mirror symmetrical to one or more planes of symmetry. The free-form surface can be a surface with n-fold symmetry, n being a whole number and greater than or equal to 1. The free-form surface may also have no axis of symmetry and no plane of symmetry at all. Different ways of describing optical surfaces, in particular anamorphic surfaces, are described in U.S. Pat. No. 6,000,798, for example, which is hereby incorporated by reference. Analytical formulae for describing non-rotationally-symmetrical surfaces, in particular anamorphic aspherical surfaces, toric surfaces or biconical aspherical surfaces, are also described in WO 01/88597, which is hereby incorporated by reference. Some optical design programmes such as Oslo® and Code V® allow optical systems to be described and designed through mathematical functions, by which it is also possible to set non-rotationally-symmetrical optical surfaces. The aforementioned mathematical descriptions relate to mathematical surfaces. An actually optically used optical surface, i.e. the physical surface of an optical element, which surface is acted upon by an illumination beam and can be described with this type of mathematical description, generally contains only a portion of the actual mathematical surface, also known as the parent surface. The mathematical surface thus extends beyond the physical optically effective surface. In so far as an optical system can be described with the aid of a reference axis, some or all of the optically used surface portions may be arranged beyond this reference axis in such a way that the reference axis divides the mathematical surface, but not, however, the actual optically used portion of this mathematical surface. Field planes arranged parallel to one another facilitate the integration of the imaging optical system into constructional surroundings. This advantage can be particularly significant when the imaging optical system is used in a scanning projection exposure installation, since the scan directions can then be guided parallel to one another. A maximum angle of reflection of 25° (e.g., a maximum angle of reflection of 20°, a maximum angle of reflection of 16°) can allow the imaging optical system to be used in a highly effective manner as a projection optical system for an EUV projection exposure installation, since the mirrors, over the entire aperture, i.e. the entire usable reflective surface, thereof, may then be covered with consistently highly reflective layers. This advantage can be important in particular for the p-polarisation components of reflected radiation, since the reflectivity of p-polarisation components decreases rapidly in the case of elevated angles of reflection. An imaging optical system, wherein the quotient of a maximum angle of reflection of the imaging light within the imaging optical system and the numerical aperture thereof on the image side is at most 40°, can allow a good compromise to be achieved between high EUV throughput and optimised pattern resolution in an EUV projection exposure installation. A mirror arranged before the last mirror in the imaging light path in the region of a pupil plane and having a convex basic shape allows good Petzval correction of the imaging optical system to be achieved. An imaging optical system having at least four mirrors (e.g., six mirrors) can be particularly suitable for the construction of an imaging optical system that is both compact and well-corrected in terms of its imaging errors. Imaging optical systems having mirrors with angular magnification of the principal ray, wherein at least two of the mirrors have a negative angular magnification of the principal ray, and wherein a mirror with positive angular magnification of the principle ray is arranged between two mirrors with negative angular magnification of the principal ray, can allow systems with low maximum angles of reflection to be achieved. Imaging optical systems with three mirrors and a negative angular magnification of the principal ray are also possible. The angular magnification of the principal ray is defined as the angle between a principal ray belonging to a central field point and a reference axis. The reference axis is perpendicular to the object plane of the projection exposure installation and extends through the centre point of the object field. A beam angle of a central imaging beam, directed through the last mirror and essentially through a pupil, of a central object point of greater than 85° relative to the image plane produces merely a low lateral image shift in the image plane when defocusing. An imaging optical system, wherein the imaging light path directed through the last mirror has an intermediate image being arranged in an intermediate image plane in the region of the through-hole in the mirror, a portion of the optical system between the object plane and the intermediate image plane having a reducing magnification level of at least 2× can allow a relatively large penultimate mirror in the light path before the image field to be used. This can reduce the maximum angle of reflection and can also reduce the extent of pupil obscuration if the penultimate mirror is obscured. It is also possible to achieve magnification of the portion of the optical system of greater than 2× (e.g., greater than 2.5×, greater than 3.0×, 3.2×). An arrangement, wherein a mirror, which is arranged so as to be the penultimate mirror in the imaging light path, has a through-hole for imaging light to pass through, the image plane being arranged behind the penultimate mirror so as to be off-centre by not more than a fifth of the diameter of the penultimate mirror (e.g., to be central) relative to the penultimate mirror, can allow a penultimate mirror with a relatively small through-hole to be used. This can ensure a stable penultimate mirror and low pupil obscuration. A slightly curved penultimate mirror having a radius of curature greater than 500 mm (e.g., greater than 1,000 mm, greater than 1,500 mm) can allow a small through-hole relative to the diameter of the mirror to be achieved in the penultimate mirror at a given image-side numerical aperture. An image field greater than 1 mm 2 can lead to good throughput when the imaging optical system is used in a projection exposure installation. An image-side numerical aperture on the image side of at least 0.4 (e.g., at least 0.45, at least 0.5, at least 0.55, at least 0.6, at least 0.65, at least 0.7) can allow high resolution of the imaging optical system to be achieved. An image-side telecentric imaging optical system can allow, for example, the system to refocus in the image plane without thereby changing the imaging magnification and thus can increase the flexibility of use of the imaging optical system. On the object-side, the imaging optical system can be formed in such a way that individual rays which are associated with different object field points but with the same exposure direction, enter the imaging optical system from the object field in a convergent manner. Alternatively, it is also possible for the individual rays of this type to enter the imaging optical system in a divergent or parallel manner. The latter case results in an object-side telecentric imaging optical system. A low object-image shift of less than 100 mm (e.g., less than 10 mm, less than 1 mm) can lead to a compact imaging optical system and, in addition, facilitates optical system test methods, in which the imaging optical system is rotated about an axis extending through the object or image field and located perpendicular to the corresponding field plane, since the object or image field then does not shift too far during rotation. At least one pair of adjacent mirrors, wherein the mirrors are at a distance from one another, perpendicular to the object plane and/or to the image plane, of more than 40% of the distance between the object field and the image field, can allow small angles of incidence to be observed in the light path of the imaging light through the imaging optical system. Due to the small angles of incidence, it is also possible to achieve highly reflective mirrors in the EUV wavelength range. In particular, 2, 3, 4 or more pairs of mirrors may satisfy the distance condition. Having in the imaging optical system at least one mirror with a minimum distance of less than 25 mm from the reflection surface used to the closest imaging light path not acting upon the mirror results in an imaging optical system in which the angle of incidence on the mirrors is kept as small as possible. The advantages of small angles of incidence on mirrors has previously been discussed. In particular 2, 3 or 4 mirrors of the imaging optical system may be at the minimum distance. This minimum distance can be less than 25 mm, but optionally greater than 5 mm so the constructional demands on the mirrors are not too great. An imaging optical system, wherein the imaging light is reflected to the image field by the mirror including the through-hole for the imaging light to pass through, in which the last mirror in the imaging light path includes the through-hole, can allow a high numerical aperture to be achieved in a compact construction with minimised imaging errors. The advantages of a projection exposure installation including an imaging optical system, including a light source for the illumination and imaging light, and including a lens system for directing the illumination light to the object field of the imaging optical system, and wherein the light source for generating the illumination light is formed with a wavelength of between 10 and 30 mm, can correspond to those previously discussed with regard to the imaging optical system. The light source of the projection exposure installation may be in the form of a broadband light source and may have, for example, a bandwidth greater than 1 nm (e.g., greater than 10 nm, greater than 100 nm). In addition, the projection exposure installation may be constructed in such a way that it can be operated with light sources of different wavelengths. Corresponding advantages can also apply to the production method including the steps of providing a reticle and a wafer, projecting a structure on the reticle onto a light-sensitive layer of the wafer by using the projection exposure installation and producing a microstructure on the wafer, and the microstructured component produced thereby. Using the imaging optical system as a microlens, wherein the arrangement of the optical components when used in this way correspond to those on the condition that object plane and image plane are exchanged, and when inspecting a substrate which is to be exposed or has already been exposed with respect to projection exposure with a lithographic projection exposure installation, can result in the advantage that, in the region of the intermediate image, drilling through any very small mirrors can be avoided. Embodiments of the disclosure will be described in the following in greater detail with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically shows a projection exposure installation for microlithography; FIG. 2 shows a cross-section through a projection optical system of the projection exposure installation in FIG. 1 containing field points spaced from one another along an imaging light path; FIG. 3 shows a plan view of an image field of the projection optical system in FIG. 2 viewed from direction III in FIG. 2 ; FIG. 4 shows a cross-section through a non-rotationally-symmetrical free-form surface and through a rotationally symmetrical surface; FIG. 5 shows a cross-section through a portion of a mirror of the projection optical system in FIG. 2 ; FIG. 6 schematically shows a light path onto a mirror in the projection optical system in FIG. 2 with positive angular magnification of the principal ray; FIG. 7 schematically shows a light path onto a mirror in the projection optical system in FIG. 2 with a negative angular magnification of the principal ray; FIG. 8 shows a similar view to FIG. 1 of a projection exposure installation for microlithography; FIG. 9 shows an enlarged partial detail of a wafer exposed with the projection exposure installation in FIG. 1 or 8 , and a mirror adjacent thereto; FIG. 10 shows a view similar to that of FIG. 2 of a projection optical system; FIG. 11 shows a view similar to that of FIG. 2 of a projection optical system; FIG. 12 shows a view similar to that of FIG. 2 of a projection optical system; FIG. 13 shows a view similar to that of FIG. 11 of a microscope lens for inspecting wafers; FIGS. 14 and 15 show two further views similar to that of FIG. 2 of a projection optical system; and FIGS. 16 and 17 show views similar to that of FIG. 13 of a microscope lens for inspecting wafers. DETAILED DESCRIPTION Referring to FIG. 1 , a projection exposure installation 1 for microlithography has a light source 2 for illumination light. The light source 2 is an EUV light source which produces light in a wavelength range of between 10 nm and 30 nm. Other EUV wavelengths are also possible. In general, even any desired wavelengths, for example visible wavelengths, are possible for the illumination light guided in the projection exposure installation 1 . A light path of the illumination light 3 is very schematically shown in FIG. 1 . A lens system 5 serves to guide the illumination light 3 to an object field in an object plane 4 . The object field is imaged by a projection optical system 6 in an image field 7 (cf. FIG. 3 ) in an image plane 8 with a predetermined reduction scale. The projection optical system 6 reduces the size by a factor of 8. Other imaging magnification levels are also possible, for example 4×, 5×, 6× or even imaging magnification levels greater than 8×. An imaging magnification level of 8× is particularly suitable for illumination light with an EUV wavelength, since the object-side angle of incidence on a reflection mask can thereby remain small. An image-side aperture of the projection optical system of NA=0.5 produces an illumination angle of less than 6° on the object-side. An image magnification level of 8× does not require, in addition, unnecessarily large masks to be used. In the projection optical system 6 according to FIG. 2 , the image plane 8 is arranged parallel to the object plane 4 . A portion of a reflective mask 9 , also known as a reticle, coinciding with the object field is hereby imaged. Imaging is achieved on the surface of a substrate 10 in the form of a wafer which is supported by a substrate holder 11 . In FIG. 1 , a light beam 12 of the illumination light 3 entering the projection optical system 6 is shown schematically between the reticle 9 and the projection optical system, and a ray beam 13 of the illumination light 3 exiting from the projection optical system 6 is shown schematically between the projection optical system 6 and the substrate 10 . The image field-side numerical aperture of the projection optical system 6 in accordance with FIG. 2 is 0.50. The projection optical system 6 is telecentric on the image side. In order to aid the description of the projection exposure installation 1 an xyz cartesian coordinate system is provided in the drawings and shows the respective locations of the components represented in the figures. In FIG. 1 the x direction extends perpendicularly into the drawing plane, the y direction extends to the right and the z direction extends downwards. The projection exposure installation 1 is a scanner-type device. Both the reticle 9 and the substrate 10 are scanned in the y direction during operation of the projection exposure installation 1 . FIG. 2 shows the optical construction of the projection optical system 6 . The light path of each of three individual rays 14 , coming from five object field points which, in FIG. 2 , are on top of one another and are at a distance from one another in the y direction, is shown, the three individual rays 14 which belong to one of the five object field points each being associated to three different illumination directions for the five object field points. From object field 4 , the individual rays 14 are initially reflected by a first mirror 15 , which is denoted in the following as mirror M 1 , and are subsequently reflected by further mirrors 16 , 17 , 18 , 19 , 20 , which are also denoted in the following as mirrors M 2 , M 3 , M 4 , M 5 and M 6 in the sequence of the light path. The projection optical system 6 in FIG. 2 therefore has 6 reflective mirrors. The mirrors have a coating which is highly reflective for the wavelength of the illumination light, if required due to the wavelength, for example with EUV wavelengths. Radiation of greatly differing wavelengths may also be guided in the lens system 5 and the projection optical system 6 , since these optical systems have substantially achromatic properties. In these optical systems it is therefore possible, for example, to direct an adjusting laser or to operate an autofocusing system, at the same time using a wavelength for the illumination light that differs greatly from the operating wavelengths of the adjusting laser or the autofocusing system. An adjusting laser can thus operate at 632.8 nm, 248 nm or 193 nm, while, at the same time, an illumination light is operated in the range between 10 and 30 nm. The mirrors 15 , 17 and 19 have a convex basic shape and can thus be described by a convex best-fitted surface. The third mirror 17 in particular has a convex basic shape. The mirrors 16 , 18 and 20 have a concave basic shape and can thus be described by a concave best-fitted surface. In the following description, this type of mirror is referred to in a simplified manner merely as convex or concave. The concave mirror 17 provides good Petzval correction in the projection optical system 6 . The individual rays 14 , which come from spaced object field points and are associated with the same illumination direction, enter the projection optical system 6 in a convergent manner between the object plane 4 and the first mirror M 1 . The design of the projection optical system 6 can be adapted in such a way that the same illumination directions for the individual rays 14 associated with the object field points also extend in a divergent manner from, or in a parallel manner to, one another between these components. The latter variant corresponds to a telecentric light path on the object side. The individual rays 14 belonging to a particular illumination direction of the five object field points 3 merge in a pupil plane 21 of the projection optical system 6 , adjacent to which the mirror 17 is arranged. The mirror 17 is therefore also known as a pupil mirror. An aperture stop may be arranged in the pupil plane 21 for limiting the illumination light ray beam. The aperture stop may be provided by a mechanical and removable stop or in the form of an appropriate coating applied directly to the mirror M 3 . The mirrors 15 to 18 image the object plane 4 in an intermediate image plane 22 . The intermediate image-side numerical aperture of the projection optical system 6 is 0.2. The mirrors 15 to 18 form a first portion of the imaging optical system of the projection optical system 6 with a reducing magnification level of 3.2×. The following mirrors 19 and 20 form a further portion of the imaging optical system of the projection optical system 6 with a reducing magnification level of 2.5×. In the sixth mirror 20 , in the region of the intermediate image plane 22 , a through-hole 23 is formed, through which the illumination or imaging light 3 passes after reflection by the fourth mirror 18 towards the fifth mirror 19 . In turn, the fifth mirror 19 has a central through-hole 24 through which the ray beam 13 passes between the sixth mirror 20 and the image field 8 . The fifth mirror 19 , which, together with the sixth mirror 20 , images the illumination or imaging light 3 from the intermediate image plane 22 in the image plane 8 , is arranged in the vicinity of a further pupil plane 25 , conjugate to the first pupil plane 21 , of the projection optical system 6 . The further pupil plane 25 is typically located in the light path of the imaging light 3 between the fifth mirror 19 and the sixth mirror 20 , so there is a physically accessible stop plane at the location of the further pupil plane 25 . An aperture stop can alternatively or additionally be arranged in this diaphragm plane, as previously described with respect to the aperture stop in the region of the pupil plane 21 . The projection optical system 6 has an obscuration stop arranged centrally in one of the pupil planes 20 , 25 . By this means the beam portions of the projection light path, associated with the central through-holes 23 , 24 in the mirrors 20 , 19 , are obscured. The construction of the projection optical system 6 can therefore also be termed construction with central pupil obscuration. A marked individual ray 14 , which connects a central object field point to a centrally illuminated point in the entrance pupil of the projection optical system 6 in the entrance pupil plane 21 , will also be referred to in the following as the principal ray 26 of a central field point. The principal ray 26 of the central field point makes approximately a right angle with the image plane 8 after reflection on the sixth mirror 20 and thus extends approximately parallel to the z-axis of the projection exposure installation 1 . The angle is greater than 85° in any case. The image field 7 is rectangular. The aspect ratio of the image field 7 is not shown to scale in FIG. 3 . The image field 7 extends by 13 mm parallel to the x direction. The image field 7 extends by 1 mm parallel to the y direction. The image field 7 is located centrally behind the fifth mirror 19 , as shown in FIG. 3 . A radius R of the through-hole 24 can be calculated from: R = 1 2 · D + d w · NA . D is the diagonal of the image field 7 . d w is the working distance of the mirror 19 from the image plane. NA is the numerical aperture on the image side. All six mirrors 15 to 20 of the projection optical system 6 are in the form of free-form surfaces which cannot be described by a rotationally symmetrical function. Other configurations of the projection optical system 6 are also possible, in which at least one of the mirrors 15 to 20 includes a free-form reflection surface of this type. Production of a free-form surface 27 of this type from a rotationally symmetrical reference surface 28 will be described in the following with reference to FIG. 4 . First of all, information on the characterisation of the free-form surface under consideration is obtained. The reference surface 28 can, for example, be a rotationally symmetrical asphere. Part of the design information may be the radius of curvature of the reference surface 28 , which is also referred to as 1/c, c denoting the vertex curvature of the reference surface 28 . A conical constant k of the reference surface 28 and polynomial coefficients which describe the reference surface 28 are also part of the information. Alternatively or additionally, the information characterising the reference surface 28 can also be obtained from a surface measurement of a reference mirror surface, for example, by using an interferometer. This type of surface measurement produces a function z′(x′, y′), which describes the reference surface 28 , z′ denoting the rising height of the reference surface 28 along the z′-axis for different (x′, y′) coordinates, as shown in FIG. 4 . This first step in designing the free-form surface also includes determining the portion of the mirror surface, which is only defined by the surface description and is initially unlimited, that will actually be used for reflecting illumination or imaging light 3 during imaging of the object field in the image field 7 . The region is also referred to as the footprint. The footprint of the mirror can be at least approximately determined by ray tracing of the projection optical system 6 . Examples for a possible footprint in the x dimension are provided in FIG. 4 . x min refers to the lower limit and x max refers to the upper limit for the exemplary footprint. The data above x max and below x min are similarly calculated within specific limits so that no undesired edge effects arise when determining the free-form surface 27 . After the information characterising the reference surface 28 has been determined, a local coordinate system for the reference surface 28 is introduced, in which both decentration and tilting of the reference surface 28 are zero. The z′-axis is thus the axis of rotational symmetry of the aspherical reference surface 28 or, if the reference surface was obtained by a surface measurement, the optical axis of the measuring device, for example the interferometer. The z′-axis is generally displaced parallel to and tilted relative to the z-axis of the xyz coordinate system of the projection exposure installation 1 . This also applies to the other coordinate axes x′, y′. This parallel displacement or tilting is determined in the initial step in the optical design of the free-form surface. As an alternative to an asphere, the reference surface 28 may also be a spherical surface. The origin of the coordinates x c , y c , z c for describing the spherical reference surface 28 generally differs from the origin of the xyz coordinate system of the projection exposure installation 1 . After the reference surface 28 has been determined, a local distance d i (i=1 . . . N) between a number of points on the reference surface 28 and points on the free-form surface 27 parallel to the z′-axis is determined. The different local distances d i are then varied until a set of secondary conditions is satisfied. The secondary conditions are predetermined limit values for specific imaging errors and/or illumination properties of the projection optical system 6 . The free form surface can be mathematically described by the following equation: Z = cr 2 1 + 1 - ( 1 + k ) ⁢ c 2 ⁢ r 2 + ∑ j = 2 66 ⁢ ⁢ C j ⁢ X m ⁢ Y n in which: j = ( m + n ) 2 + m + 3 ⁢ n 2 + 1 Z is the rising height of the free-form surface parallel to a Z-axis which can, for example be parallel to the z′-axis in FIG. 4 . c is a constant corresponding to the vertex curvature of a corresponding asphere. k corresponds to a conical constant of a corresponding asphere. C j are the coefficients of the monomials X m Y n . The values of c, k and C j are generally determined on the basis of the desired optical properties of the mirror inside the projection optical system 6 . The order of the monomial, m+n, can be varied as desired. A monomial of a higher order can lead to a design of the projection optical system with improved image error correction, but is, however, more complex to calculate. m+n can have values of between 3 and more than 20. Free-form surfaces can also be described mathematically by Zernike polynomials, which are described, for example, in the manual of the optical design program CODE V®. Alternatively, free-form surfaces can be described with two-dimensional spline surfaces. Examples thereof are Bezier curves or non-uniform rational basis splines (NURBS). Two-dimensional spline surfaces can be described, for example, by a grid of points in an xy-plane and related z-values, or by the points and their related gradients. Depending on the respective type of spline surface, the complete surface will be obtained by interpolating between the grid points by using, for example, polynomials or functions which have specific properties with respect to their continuity and differentiability. Examples thereof include analytical functions. The mirrors 15 to 20 have multiple reflective coatings for optimising the reflection thereof for the incident EUV illumination light 3 . Reflection is better the closer the angle of incidence of the individual rays 14 on the mirror surface is to the perpendicular incidence. The projection optical system 6 has very small angles of reflection for all of the individual rays 14 . Half of the angle between the individual ray 14 striking a point on one of the mirrors 15 to 20 and the individual ray 14 reflected from this point will be referred to in the following as the angle of reflection of this point. The maximum angle of reflection in the projection optical system 6 is the angle of the individual ray 14 at the outer edge of the fifth mirror 19 . This angle α is approximately 16° in the projection optical system 6 . The quotient of the maximum angle of reflection α and the numerical aperture is thus 32° in the projection optical system 6 shown in FIG. 2 . The dependence of the size of the angle of reflection on the position of the point of incidence on the reflection mirror will be explained schematically in the following with an example of a sample reflection mirror 29 , shown in FIG. 5 . In the picture a divergent beam of individual rays 14 a , 14 b , 14 c strikes a reflection surface 30 of the sample reflection mirror 29 . The reflection surface 30 is convex. Due to the collective effect of the reflection surface 30 , the incident descending beam made of individual rays 14 a , 14 b and 14 c is deflected forming a reflected convergent beam. The individual ray 14 a striking closest to the edge on the reflection surface 30 is deflected with the largest angle of reflection α, the centre individual ray 14 b is deflected with an angle of reflection β which is smaller in comparison thereto and the individual ray 14 c furthest from the edge of the sample reflection mirror 29 is deflected by the smallest angle of reflection γ. The light path within the projection optical system 6 can additionally be characterised by the sequence of angular magnification of the principal ray. This will be explained in the following with reference to the schematic drawings 6 and 7 . In FIG. 6 , the principal ray 26 is radiated onto a sample reflection mirror 31 at an angle α to a reference axis 32 extending perpendicular to the object plane 4 of the projection exposure installation 1 . On the side of the object field, i.e. up to and inclusive of the mirror M 4 , the reference axis 32 is additionally defined by the centre of the object field. The reference axis 32 generally does not coincide with the z-axis but runs parallel to the axis. After being reflected by the sample reflection mirror 31 , the principal ray 26 is reflected back at an angle β to the reference axis 32 . Since both angles α, β are between 0 and 90°, the quotient tan α/tan β is positive. The sample reflection mirror 31 therefore has a positive angular magnification of the principal ray. FIG. 7 shows the case of negative angular magnification of the principal ray. The incident principal ray 26 intersects the reference axis 32 at an angle α which is between 0 and 90°. The principal ray 26 reflected by a sample reflection mirror 33 virtually encloses an angle β between 90 and 180° with the reference axis 32 . In this case the quotient tan α/tan β is thus negative. In the projection optical system 6 , the first mirror 15 has negative angular magnification of the principal ray. The second mirror 16 has positive angular magnification of the principal ray. The third mirror 17 has negative angular magnification of the principal ray. The angular magnification of the fourth mirror 18 is infinite, since the angle is 180° at that location. FIG. 8 again shows a slightly modified representation of the projection exposure installation 1 for clearly showing a further characterising value of the projection optical system 6 , namely the object-image shift d ois . This is defined as the distance between a perpendicular projection of the central object point onto the image plane 8 and the central image point. In the projection optical system 6 shown in FIG. 2 , the object-image shift d ois is less than 1 mm. FIG. 9 demonstrates a further characteristic of the projection optical system 6 , namely the free working distance d w . This is defined as the distance between the image plane 8 and the closest portion 34 thereto of one of the mirrors of the projection optical system 6 , i.e. mirror 19 in the embodiment shown in FIG. 2 . In the projection optical system 6 , the free working distance d w is 40 mm. The fifth mirror 19 , which is closest to the image plane 8 , can therefore be constructed having a thickness that provides sufficient stability of the fifth mirror 19 . Materials for mirrors of this type include, for example, quartz, zerodur or silicon carbide compounds. Other materials with ultra low expansion properties may also be used. Examples of materials of this type are known from products sold by Corning, USA, under the name “ULE”. The optical data of the projection optical system 6 are summarised in the following: The image-side numerical aperture NA is 0.5. The size of the image field is 1×13 mm 2 . The reducing magnification level is 8×. The image field 7 is rectangular. The wavelength of the illumination light is 13.5 nm. The sequence of the optical effects of the mirrors M 1 to M 6 (negative N; positive P) is NPNPNP. Principal rays enter the projection optical system in a convergent manner from the object plane. An aperture stop is arranged on the mirror M 3 for limiting the illumination light at the edge. The z-distance between the object plane 4 and the image plane 8 is 1,500 mm. The object-image shift is 0.42 mm. 5.9% of the illuminated surfaces in the pupil planes are obscured. The projection optical system has a wave front error (rms) of 0.02 in units of the wavelength of the illumination light 3 . The distortion is 12 nm. The field curvature is 9 nm. The angle of the principal ray at the central object field point is 5.9°. The mirror M 1 has dimensions (x/y) of 117×61 mm 2 . The mirror M 2 has dimensions of 306×143 mm 2 . The mirror M 3 has dimensions of 80×77 mm 2 . The mirror M 4 has dimensions of 174×126 mm 2 . The mirror M 5 has dimensions of 253×245 mm 2 . The mirror M 6 has dimensions of 676×666 mm 2 . The sequence of the principal ray angle of incidence, of the principal ray 26 of the central object field point, on the mirrors M 1 to M 6 is 16.01°, 7.14° 13.13°, 7.21°, 0.0° and 0.0°. The sequence of the maximum angle of incidence on the mirrors M 1 to M 6 is 22.55°, 9.62°, 13.90°, 10.16°, 16.23°, 4.37°. The sequence of bandwidths of the angle of incidence on the mirrors M 1 to M 6 is 13.12°, 5.07°, 1.58°, 6.10°, less than 16.23° and less than 4.37°. The working distance in the object plane 4 is 100 mm. The working distance in the image plane 8 is 40 mm. The ratio of the distance between the object plane 4 and the mirror M 1 and the distance between the object plane 4 and the mirror M 2 is 4.25. Between each of the adjacent mirrors M 2 -M 3 , M 4 -M 5 , M 5 -M 6 and also between the mirror M 6 and the image plane 8 there is a distance of greater than 40% of the z-distance between the object plane 4 and the image plane 8 . The mirrors M 1 and M 4 have a minimum distance from the used reflection surface to the closest imaging light path not acting on the mirror (free board) of less than 25 mm. The optical design data of the reflection surfaces of the mirrors M 1 to M 6 of the projection optical system 6 can be gathered from the following tables. The first of the tables shows the respective reciprocal value of the vertex curvature (radius) and a distance value (thickness), which corresponds to the z-distance of adjacent elements in the light path, starting from the object plane, for the optical components and the aperture stop. The second table shows the coefficients C j of the monomials X m Y n in the aforementioned free-form surface equation for the mirrors M 1 to M 6 . At the end of the second table the value by which the respective mirror is decentred (Y-decenter) and rotated (X-rotation) from a mirror reference design is given in millimeters. This corresponds to the parallel displacement and tilting in the free-form surface design method described above. Displacement thus takes place in the y direction and tilting takes place about the x axis. The angle of rotation is given in degrees. Surface Radius Thickness Mode Object INFINITY 425.420 Mirror 1 294.947 −325.420 REFL Mirror 2 681.039 690.757 REFL Mirror 3 319.431 0.000 REFL STOP INFINITY −244.337 Mirror 4 396.876 913.580 REFL Mirror 5 1749.322 −620.710 REFL Mirror 6 834.214 660.710 REFL Image INFINITY 0.000 Coefficient M1 M2 M3 M4 M5 M6 K −8.972907E−01  −2.722153E−01  6.009025E+00 −2.083103E−01 3.438760E+01 3.027724E−01 Y 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 X2 −6.723739E−04  −9.397624E−05  −5.616960E−04  −1.596929E−04 9.008585E−06 3.436254E−05 Y2 −7.259542E−04  −1.245430E−04  −4.962660E−04  −1.209634E−04 2.711820E−06 3.328586E−05 X2Y −2.611787E−07  9.438147E−09 −6.471824E−07  −1.397345E−07 −3.166886E−08  4.403654E−10 Y3 1.848873E−07 2.540415E−08 4.939085E−07 −1.842875E−07 5.311486E−09 6.726500E−10 X4 −5.585253E−10  −3.707750E−11  −2.414232E−08  −1.057114E−10 9.436063E−10 1.898115E−12 X2Y2 −1.454988E−09  −1.447610E−10  −4.434814E−08  −5.420267E−11 1.946694E−09 4.974829E−12 Y4 −5.523329E−09  −2.392090E−11  −1.815299E−08   4.380159E−10 9.997897E−10 3.488151E−12 X4Y −1.364069E−12  1.084325E−15 −3.114225E−11  −1.197000E−12 5.182403E−14 4.428526E−16 X2Y3 6.732062E−12 1.382697E−13 9.802932E−11 −1.950774E−12 4.779360E−13 1.769320E−16 Y5 3.635430E−11 0.000000E+00 7.767198E−11 −1.559300E−12 3.401358E−13 4.373202E−16 X6 −2.750390E−15  −9.087823E−17  −9.415776E−13  −4.463189E−16 1.620585E−15 9.932173E−19 X4Y2 2.324635E−14 −5.352295E−17  −3.094331E−12   7.684993E−15 5.526453E−15 3.332327E−18 X2Y4 3.956161E−15 −2.030722E−16  −3.217471E−12   3.107748E−15 5.847027E−15 3.759258E−18 Y6 −1.092384E−13  −8.567898E−17  −7.281446E−13  −7.204126E−16 1.552120E−15 1.038153E−18 X6Y −1.179589E−16  4.377060E−19 −1.789065E−16  −1.451963E−19 3.245847E−19 1.324484E−22 X4Y3 −2.570887E−16  0.000000E+00 1.023466E−14 −4.269245E−17 1.564405E−18 −9.051915E−22  X2Y5 −8.917936E−17  7.695621E−21 1.492914E−14 −1.217398E−17 2.326082E−18 −1.811267E−22  Y7 1.236168E−16 0.000000E+00 4.771084E−15  5.163018E−18 7.533041E−19 2.904675E−22 X8 7.305784E−20 −2.087892E−22  −4.992347E−17  −9.852110E−22 5.510114E−21 −9.878544E−26  X6Y2 6.107242E−19 −8.775175E−22  −2.298856E−16  −2.713369E−20 2.453885E−20 6.254655E−25 X4Y4 5.443174E−19 −2.629666E−22  −3.296922E−16   3.809184E−20 3.817638E−20 4.270350E−24 X2Y6 −6.091249E−19  −8.692919E−23  −1.689920E−16   3.730606E−21 2.483560E−20 4.657493E−24 Y8 −2.536724E−19  8.059798E−24 −2.318537E−17  −7.839829E−21 6.692413E−21 1.504196E−24 X8Y 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 X6Y3 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 X4Y5 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 X2Y7 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 Y9 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 X10 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 X8Y2 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 X6Y4 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 X4Y6 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 X2Y8 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 Y10 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 Nradius   1.00E+00   1.00E+00   1.00E+00     1.00E+00   1.00E+00   1.00E+00 Y-decenter 68.139 −264.855 176.907 −28.983 101.914 97.590 X-rotation −1.258  25.000  1.304  25.000  0.098  0.498 FIG. 10 shows a projection optical system 35 , which can be used, instead of the projection optical system 6 , in the projection exposure installation 1 . Components or reference quantities which correspond to those which have previously been described with reference to FIGS. 1 to 9 have the same reference numerals and will not be discussed in detail again. The projection optical system 35 also has a total of six reflective mirrors, which, starting from the object plane 4 in the light path sequence, have reference numerals 36 to 41 , and will also be referred to in the following as mirrors M 1 to M 6 . The mirrors 36 to 41 all have reflective free-form surfaces which cannot be described by a rotationally symmetrical function. The mirrors 36 , 38 and 40 have a convex basic shape and the mirrors 37 , 39 , 41 have a concave basic shape. The projection optical system 35 has a reduction factor of 8. The projection optical system 36 has an image-side numerical aperture of 0.5. The dimensions of the image field 7 of the projection optical system 35 are exactly the same as those of the projection optical system 6 . The intermediate image-side numerical aperture is 0.28. The first mirror 36 has negative angular magnification of the principal ray. The second mirror 37 has positive angular magnification of the principal ray. The third mirror 38 has negative angular magnification of the principal ray. The fourth mirror 39 has infinite angular magnification of the principal ray since the principal ray 26 extends from the fourth mirror 39 so as to be perpendicular to the image plane 8 . In the projection optical system 35 , the object-image shift is markedly greater than in the projection optical system 6 and is 134 mm. The maximum angle of reflection α, which is also achieved by the rays at the edge of the fifth mirror 40 in the projection optical system 35 , is 17°. The quotient of the maximum angle of reflection α and the image-side numerical aperture is 34°. At 42 mm, the free working distance d w in the projection optical system 35 is comparable with the free working distance of the projection optical system 6 . The optical data of the projection optical system 35 are summarised again in the following: The image-side numerical aperture NA is 0.5. The dimensions of the image field 7 are 1×13 mm 2 . The reducing magnification level is 8×. The image field 7 is rectangular. The wavelength of the illumination light 3 is 13.5 nm. The sequence of the optical effects of the mirrors M 1 to M 6 (negative N; positive P) is PPNPNP. At the image-side, the projection optical system 35 is virtually telecentric. An aperture stop for limiting the illumination light at the edge is arranged on mirror M 3 . The z-distance between the object plane 4 and the image plane 8 is 1,823 mm. The object-image shift is 134 mm. 9.2% of the surfaces illuminated in the pupil planes are obscured. The angle of the principal ray at the central object field point is 6°. The mirror M 1 has dimensions (x/y) of 241×138 mm 2 . The mirror M 2 has dimensions of 377×269 mm 2 . The mirror M 3 has dimensions of 80×75 mm 2 . The mirror M 4 has dimensions of 246×197 mm 2 . The mirror M 5 has dimensions of 352×304 mm 2 . The mirror M 6 has dimensions of 776×678 mm 2 . The sequence of the angle of incidence of the principal ray of the central object field point on the mirrors M 1 to M 6 is 7.10°, 5.19°, 13.66°, 4.60°, 0.0° and 0.02°. The sequence of the maximum angle of incidence on the mirrors M 1 to M 6 is 12.23°, 5.53°, 15.43°, 7.33°, 16.98° and 5.51°. The sequence of the bandwidths of the angle of incidence on the mirrors M 1 to M 6 is 9.93°, 0.78°, 2.98°, 5.27°, less than 16.98° and less than 5.51°. The working distance in the object plane 4 is 336 mm. The working distance in the image plane 8 is 42 mm. The ratio of the distance between the object plane 4 and the mirror M 1 and the distance between the object plane 4 and the mirror M 2 is 3.04. The mirrors M 1 to M 4 have a minimum distance between the used reflection surface and the closest imaging light path which does not act upon the mirror (free board) of less than 25 mm. The distance between the object plane 4 and the mirror M 1 and the distances between the pairs of mirrors M 2 -M 3 and M 4 -M 5 is greater than 40% of the distance between the object plane and the image plane. The optical design data of the reflection surfaces of the mirrors M 1 to M 6 of the projection optical system 35 can be gathered from the following tables, which correspond to the tables for the projection optical system in accordance with FIG. 2 . Surface Radius Thickness Mode Object INFINITY 1023.157 Mirror 1 −50610.892 −686.714 REFL Mirror 2 1171.238 828.471 REFL Mirror 3 318.004 0.000 REFL STOP INFINITY −378.086 Mirror 4 413.560 994.620 REFL Mirror 5 2997.146 −612.464 REFL Mirror 6 817.300 654.356 REFL Image INFINITY 0.000 Coeff. M1 M2 M3 M4 M5 M6 K 4.156869E+03 4.620221E−02 9.990462E+00 −9.081861E−03  −2.372322E−01  6.789706E−03 Y 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2 4.219939E−05 −7.203705E−05  −2.856541E−04  −1.831594E−04  −4.114605E−05  2.674563E−06 Y2 −2.952066E−04  −8.835077E−05  1.576757E−04 −1.812758E−04  −3.733421E−05  7.346415E−06 X2Y −2.987815E−08  1.958263E−08 4.843132E−07 −7.966262E−08  −5.183892E−08  −3.629397E−09  Y3 5.768104E−07 8.430075E−08 −7.326854E−08  −9.457440E−08  −2.814518E−08  9.209304E−11 X4 2.110770E−10 2.081353E−11 1.569949E−08 −3.236129E−10  3.542926E−11 1.915378E−12 X2Y2 3.100857E−10 −1.622544E−11  3.080477E−08 −6.357050E−10  8.409285E−11 4.860251E−12 Y4 −2.322578E−10  −4.348550E−11  −9.859142E−09  −1.882466E−10  −2.084652E−11  6.490959E−14 X4Y 0.000000E+00 −7.908907E−15  0.000000E+00 1.810068E−13 1.675236E−13 −2.002515E−15  X2Y3 0.000000E+00 1.426458E−14 0.000000E+00 −2.244745E−13  1.806451E−13 −1.799322E−15  Y5 0.000000E+00 −1.321548E−14  0.000000E+00 −2.730307E−13  −1.337121E−14  3.920622E−16 X6 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X4Y2 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2Y4 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Y6 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X6Y 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X4Y3 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2Y5 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Y7 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X8 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X6Y2 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X4Y4 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2Y6 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Y8 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X8Y 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X6Y3 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X4Y5 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2Y7 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Y9 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X10 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X8Y2 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X6Y4 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X4Y6 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2Y8 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Y10 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Nradius   1.00E+00   1.00E+00   1.00E+00   1.00E+00   1.00E+00   1.00E+00 Y-decenter −242.949 −116.015 15.485 −94.370 162.630 −15.854 X-rotation  −2.051   4.274 −4.892  10.143  −3.797  −2.652 FIG. 11 shows a further configuration of a projection optical system 42 which may be used, instead of the projection optical system 6 , in the projection exposure installation 1 . Components or reference quantities which correspond to those which have previously been explained with reference to FIGS. 1 to 10 have the same reference numerals and will not again be discussed in detail. The projection optical system 42 also has six reflection mirrors which are denoted by the reference numerals 43 to 48 in accordance with their sequence in the imaging light path, starting from the object plane 4 . The mirrors will also be referred to in the following as M 1 to M 6 . In the projection optical system 42 , all of the reflection surfaces are formed as free-form surfaces which cannot be described by a rotationally symmetrical function. The first mirror 43 is concave, but has only a very slight curve so that it can be simply modified to form a mirror with a zero base curve or to form a convexly curved mirror. The second mirror 44 is concave and the third mirror 45 is convex. The fourth mirror 46 is concave. The fifth mirror 47 is convex. The sixth mirror 48 is concave. Each of the first three mirrors 43 to 45 has negative angular magnification of the principal ray. The angular magnification of the principal ray of the fourth mirror 46 is infinite since the principal ray 26 extends perpendicular to the image plane 8 after reflection by the fourth mirror 46 . The projection optical system 42 has an image-side numerical aperture of 0.5. The projection optical system 42 has an intermediate image-side numerical aperture of 0.11. In the projection optical system 42 , the free working distance d w is 20 mm. The projection optical system 42 has a reduction factor of 8. The dimensions of the image field in the projection optical system 42 correspond to those of the projection optical systems 6 and 35 . In the projection optical system 42 , the maximum angle of reflection also occurs in the outer edge rays reflected on the fifth mirror 47 and is α=16°. The quotient of the maximum angle of reflection of the illumination light 3 within the projection optical system 42 and the image-side numerical aperture is 32. The optical data of the projection optical system 42 are again summarised in the following: The image-side numerical aperture NA is 0.5. The dimensions of the image field are 1×13 mm 2 . The reducing imaging magnification level is 8×. The image field 7 is rectangular. The wavelength of the illumination light 3 is 13.5 nm. The sequence of the optical effects of the mirrors M 1 to M 6 (negative N; positive P) is PPNPNP. Principal rays enter convergently into the projection optical system 42 from the object plane 4 . An aperture stop is arranged on the mirror M 2 for limiting the illumination light at the edge. The z-distance between the object plane 4 and the image plane 8 is 1,700 mm. The object-image shift is 393 mm. 17.0% of the surfaces illuminated in the pupil planes are obscured. The projection optical system 42 has a wavefront error (rms) of 0.100 in units of the wavelength of the illumination light 3 . The distortion is 16 nm. The image field curvature is 35 nm. The angle of the principal ray at the central object field point is 6°. The mirror M 1 has dimensions (x/y) of 164×134 mm 2 . The mirror M 2 has dimensions of 312×170 mm 2 . The mirror M 3 has dimensions of 147×155 mm 2 . The mirror M 4 has dimensions of 354×196 mm 2 . The mirror M 5 has dimensions of 103×96 mm 2 . The mirror M 6 has dimensions of 457×444 mm 2 . The sequence of the principal ray angle of incidence of the principal ray 26 of the central object field point on the mirrors M 1 to M 6 is 3.54°, 5.15°, 9.11°, 4.45°, 0.01° and 0.01°. The sequence of the maximum angle of incidence on the mirrors M 1 to M 6 is 6.18°, 5.62°, 9.80°, 6.85°, 15.94°, and 2.36°. The sequence of the bandwidths of the angle of incidence on the mirrors M 1 to M 6 is 5.16°, 1.08°, 1.52°, 4.63°, less than 15.94° and less than 2.38°. The working distance in the object plane 4 is 200 mm. The working distance in the image plane 8 is 20 mm. The ratio of the distance between the object plane 4 and the mirror M 1 and the distance between the object plane 4 and the mirror M 2 is 5.07. The mirrors M 1 and M 2 have a minimum distance between the used reflection surface and the closest imaging light path which does not act upon the mirror (free board) of less than 25 mm. The distance between the object plane 4 and the mirror M 1 and the distances between the pairs of mirrors M 1 -M 2 , M 2 -M 3 , M 3 -M 4 and M 4 -M 5 are greater than 40% of the distance between the object plane and the image plane. The optical design data for the reflection surfaces of the mirrors M 1 to M 6 of the projection optical system 42 can be gathered from the following tables, which correspond to the tables previously provided for the projection optical system 6 in accordance with FIG. 2 . Surface Radius Thickness Mode Object INFINITY 1014.317 Mirror 1 −2704.152 −814.317 REFL Mirror 2 531.833 0.000 REFL STOP INFINITY 935.139 Mirror 3 491.748 −718.533 REFL Mirror 4 870.221 1263.419 REFL Mirror 5 245.485 −424.886 REFL Mirror 6 495.477 444.861 REFL Image INFINITY 0.000 Coeff. M1 M2 M3 M4 M5 M6 K 1.144605E+01 −9.050341E−01  −1.089239E+00 −6.248739E−01   2.948620E+00 1.091603E−01 Y 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00 X2 2.857150E−04 −5.920234E−04  −2.610462E−04 −1.368396E−04  −4.475618E−04 1.730506E−05 Y2 9.176083E−05 −8.321210E−04  −7.892918E−04 −2.573840E−04  −4.405714E−04 1.563424E−05 X2Y 7.455682E−07 −9.307510E−09   4.809832E−08 3.116002E−08  4.341012E−09 −3.269435E−09  Y3 4.605832E−08 −1.943924E−07  −2.212409E−07 7.169569E−09 −4.274845E−07 −4.266065E−09  X4 −3.659110E−10  −1.644174E−11   8.510237E−10 1.713005E−11  2.190981E−09 1.081076E−11 X2Y2 −1.689952E−09  −3.435735E−10   6.957800E−12 −9.146320E−12  −5.946668E−09 2.690241E−11 Y4 −2.561746E−10  −6.556489E−10   1.590530E−10 3.880664E−13 −1.024229E−08 −1.427930E−12  X4Y −3.302144E−12  −1.451447E−13  −3.859663E−12 4.923124E−14 −2.729947E−11 −2.149830E−14  X2Y3 −2.296129E−12  2.463662E−13  4.902075E−12 4.230604E−14 −2.255029E−11 5.867643E−15 Y5 4.869118E−13 2.042378E−12 −5.901335E−13 −2.503638E−15  −1.535539E−11 1.362505E−14 X6 2.532299E−14 3.607331E−16 −3.635906E−15 −1.910942E−17   5.572070E−14 1.020771E−17 X4Y2 1.050746E−14 3.556935E−15  6.819544E−14 1.635726E−16  4.514505E−13 3.413101E−17 X2Y4 2.215727E−14 8.029448E−15 −1.161921E−14 −1.548212E−17  −4.560072E−13 −1.111206E−17  Y6 −9.649794E−16  7.587037E−15  4.555774E−16 1.222675E−17 −3.875470E−13 −2.539409E−17  X6Y −1.936844E−16  −4.478100E−19   9.189317E−17 3.837055E−19 −3.689123E−15 −6.718113E−20  X4Y3 5.354672E−17 1.140666E−17 −4.339139E−16 2.254755E−19 −3.854918E−15 7.351666E−20 X2Y5 −3.646598E−17  3.260549E−17 −2.644153E−17 −8.425001E−20   9.184510E−16 1.186287E−19 Y7 6.063079E−19 9.615056E−17  1.324974E−18 −1.850786E−21  −2.798829E−15 6.587133E−20 X8 5.617315E−19 1.744698E−21  8.327575E−19 2.970358E−21  4.324289E−18 5.187555E−23 X6Y2 5.094397E−19 3.594344E−20 −9.344050E−19 2.069107E−21  4.500525E−17 3.412692E−23 X4Y4 −2.079112E−19  1.260510E−19  1.229358E−18 −7.743007E−23  −2.240628E−17 6.720118E−23 X2Y6 −1.595633E−20  1.627768E−19 −2.763971E−20 1.708991E−22 −4.013864E−17 2.519384E−23 Y8 1.940634E−21 4.827783E−19  5.031625E−21 −1.299209E−23  −6.317984E−18 −9.073694E−23  X8Y −3.793003E−21  2.116730E−23 −7.801057E−21 1.432927E−23 −4.043104E−19 −8.431854E−26  X6Y3 −6.345560E−22  2.804678E−22  4.289367E−21 2.349972E−24 −4.743148E−19 5.385876E−25 X4Y5 −1.925796E−22  9.316727E−22 −1.053643E−21 −3.225767E−25   1.860041E−19 1.381096E−24 X2Y7 8.214685E−23 2.388724E−21  8.375537E−22 2.766796E−25  1.013965E−19 1.617787E−24 Y9 1.703546E−24 4.526481E−21 −2.966098E−23 1.800745E−26  3.422243E−22 6.810995E−25 X10 1.991274E−24 5.335545E−26  1.741970E−24 7.205669E−28  0.000000E+00 −5.791957E−28  X8Y2 6.491228E−24 1.977752E−24  1.571441E−23 1.716942E−26  0.000000E+00 −1.179271E−26  X6Y4 4.259954E−25 7.623140E−24 −1.086567E−23 0.000000E+00  0.000000E+00 −1.124411E−26  X4Y6 8.190088E−25 1.642262E−23 −1.531617E−24 0.000000E+00  0.000000E+00 −6.908146E−27  X2Y8 −3.305040E−26  2.718356E−23 −1.734683E−24 4.000570E−29  0.000000E+00 −4.575592E−27  Y10 −5.699224E−27  2.657964E−23  5.982496E−26 4.841412E−30  0.000000E+00 −1.211899E−27  Nradius   1.00E+00   1.00E+00     1.00E+00   1.00E+00     1.00E+00   1.00E+00 Y-decenter −262.562 −14.529 −294.373 184.266 −286.525 −283.609 X-rotation  −5.767  −4.073   2.602 −13.391   0.685   0.041 FIG. 12 shows a projection optical system 49 which can be used in the projection exposure installation 1 in the case of UV illumination instead of the projection optical system 6 . Components or reference quantities which correspond to those which have been previously explained with reference to FIGS. 1 to 11 have the same reference numerals and will not be discussed in detail again. The projection optical system 49 also has six reflection mirrors which are denoted with the reference numerals 50 to 55 in accordance with their sequence in the imaging light path, from the object plane 4 . The mirrors will also be referred to in the following as M 1 to M 6 . In the projection optical system 49 , all of the reflection surfaces are formed as free-form surfaces which cannot be described by a rotationally symmetrical function. In the configuration shown in FIG. 12 , the sequence of the base curves of the mirror is the same as in the configuration of FIG. 11 . Again, the first mirror is only very slightly curved and can thus be simply converted into a mirror with a zero base curve (planar base curve) or to a mirror with a convex base curve. Each of the first three mirrors 50 to 52 has negative angular magnification of the principal ray. The angular magnification of the principal ray of the fourth mirror 53 is infinite since the principal ray 26 extends perpendicular to the image plane 8 after reflection on the fourth mirror 53 . The projection optical system 49 has an image-side numerical aperture of 0.7. The projection optical system 49 has an intermediate image numerical aperture of 0.14. In the projection optical system 49 , the free working distance d w is 20 mm. The projection optical system 49 has a reduction factor of 8. In the projection optical system 49 , the image field dimensions correspond to those of the projection optical systems 6 , 35 and 42 . The image field dimensions are 13×1 mm 2 . In the projection optical system 49 , the maximum angle of reflection also occurs in the outer edge rays reflected on the fifth mirror 54 and is α=23.8°. The quotient of the maximum angle of reflection of the imaging light 3 within the projection optical system and the image-side numerical aperture is 34°. The optical data for the projection optical system 49 are again summarised in the following: The image-side numerical aperture NA is 0.7. The dimensions of the image field 7 are 1×13 mm 2 . The reducing magnification level is 8×. The image field 7 is rectangular. The wavelength of the illumination light 3 is 193.0 nm. The sequence of the optical effects of the mirrors M 1 to M 6 (negative N; positive P) is PPNPNP. Principal rays enter the projection optical system 49 in a convergent manner from the object plane 4 . An aperture stop is arranged on the mirror M 2 for limiting the illumination light at the edge. The z-distance between the object plane 4 and the image plane 8 is 1,700 mm. The object-image shift is 549 mm. 11.6% of the surfaces illuminated in the pupil planes are obscured. The projection optical system 49 has wavefront error (rms) of 0.053 in units of the wavelength of the illumination light. The distortion is 400 nm. The image field curvature is 130 nm. The angle of the principal ray on the central object field point is 6°. The mirror M 1 has dimensions (x/y) of 204×184 mm 2 . The mirror M 2 has dimensions of 652×271 mm 2 . The mirror M 3 has dimensions of 192×260 mm 2 . The mirror M 4 has dimensions of 515×347 mm 2 . The mirror M 5 has dimensions of 162×153 mm 2 . The mirror M 6 has dimensions of 643×619 mm 2 . The sequence of the principal ray angle of incidence of the principal ray 26 of the central object field point on the mirrors M 1 to M 6 is 5.40°, 8.76°, 11.83°, 5.37°, 0.01° and 0.02°. The sequence of the maximum angle of incidence on the mirrors M 1 to M 6 is 9.70°, 10.06°, 13.22°, 8.94°, 24.01° and 3.62°. The sequence of the bandwidths of the angle of incidence on the mirrors M 1 to M 6 is 8.23°, 2.81°, 3.10°, 6.95°, less than 24.01° and less than 3.62°. The working distance in the object plane 4 is 200 mm. The working distance in the image plane 8 is 20 mm. The ratio of the distance between the object plane 4 and the mirror M 1 and the distance between the object plane 4 and the mirror M 2 is 5.11. The mirrors M 1 to M 3 have a minimum distance between the used reflection surface and the closest imaging light path which does not act upon the mirrors (free board) of less than 25 mm. The distance between the object plane 4 and the mirror M 1 and the distances between the pairs of mirrors M 1 -M 2 , M 2 -M 3 , M 3 -M 4 , M 4 -M 5 are greater than 40% of the distance between the object and the image plane. The optical design data for the reflection surfaces of the mirrors M 1 to M 6 can be gathered from the following tables which correspond to those of the projection optical system 6 of FIG. 2 described above. Surface Radius Thickness Mode Object INFINITY 1022.710 Mirror 1 −7390.359 −822.710 REFL Mirror 2 513.847 0.000 REFL STOP INFINITY 942.710 Mirror 3 501.145 −842.710 REFL Mirror 4 843.206 1380.024 REFL Mirror 5 578.181 −417.314 REFL Mirror 6 496.039 437.290 REFL Image INFINITY 0.000 Coeff. M1 M2 M3 M4 M5 M6 K 3.481687E+02 −9.241869E−01  −7.566344E−01  −5.019615E−01 1.965937E+01  1.267270E−01 Y 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00  0.000000E+00 X2 6.555377E−04 −5.511453E−04  2.158158E−04 −1.699472E−04 2.894217E−04  5.126962E−06 Y2 3.295088E−05 −8.776483E−04  −9.084036E−04  −2.883162E−04 3.472889E−04  1.671956E−05 X2Y −4.245568E−07  3.113324E−08 7.395458E−07  7.821775E−08 −4.476295E−07  −6.764774E−09 Y3 1.390824E−08 −1.918862E−07  8.435308E−08 −2.628080E−08 5.451515E−08 −2.659596E−09 X4 −3.307013E−10  −1.191040E−11  3.063977E−09 −3.668514E−11 5.377968E−09  8.032524E−12 X2Y2 3.290269E−09 −6.921528E−11  1.233667E−11  1.187534E−10 2.249411E−08  2.023497E−11 Y4 −1.463471E−10  5.786874E−11 −6.021292E−12  −1.106757E−10 7.037151E−09 −5.631157E−12 X4Y 2.736617E−12 4.032934E−15 −6.984058E−13  −8.039415E−14 −1.260298E−12  −5.006977E−15 X2Y3 3.522297E−13 −1.166725E−13  −2.454747E−12   5.957814E−13 −1.250078E−11  −5.698119E−15 Y5 −2.490692E−13  2.590308E−12 −3.745572E−13  −1.408338E−14 −2.442407E−11  −7.179108E−15 X6 −1.862455E−14  6.281324E−18 −2.148629E−14  −6.004672E−17 1.997946E−13 −1.011352E−17 X4Y2 −7.981936E−14  4.496399E−17 −1.242837E−14  −6.611499E−16 2.590470E−13 −6.909855E−17 X2Y4 −4.901925E−14  −3.029567E−16  −3.758114E−15   9.515240E−16 −2.673556E−13  −1.224111E−16 Y6 2.434885E−16 1.266995E−14 1.367511E−16  6.466128E−17 2.511816E−13 −4.838450E−17 X6Y 2.013361E−16 1.162633E−19 1.149857E−17 −3.125791E−19 −1.332065E−15  −1.469592E−20 X4Y3 3.552832E−16 1.010087E−18 −1.441396E−16  −1.842092E−18 −2.995433E−15  −1.117419E−19 X2Y5 −9.924040E−19  −2.022287E−19  −1.400280E−17   1.100935E−18 −2.362122E−15  −1.093754E−19 Y7 1.950700E−18 −1.249257E−17  6.126115E−19  3.018212E−20 2.029387E−15 −2.279935E−20 X8 −1.816371E−19  8.241847E−23 1.607901E−19 −2.596493E−23 6.322415E−18 −1.205865E−22 X6Y2 −1.231881E−18  1.602604E−21 2.552251E−19 −7.939427E−22 1.136621E−17 −2.391492E−22 X4Y4 −1.457234E−19  1.343999E−20 −6.277420E−19  −2.461049E−21 −7.995361E−19  −1.719723E−22 X2Y6 5.627869E−19 1.086725E−20 2.371593E−20  9.514060E−22 −3.361939E−17  −2.245468E−22 Y8 3.626451E−21 −2.072810E−20  −3.369745E−21  −6.523915E−23 −4.042492E−18  −1.070962E−22 X8Y 1.644403E−21 5.521298E−25 7.387878E−22 −4.934005E−26 −4.739358E−20   1.327526E−25 X6Y3 2.012939E−21 1.839641E−23 6.948031E−22 −5.010250E−25 −3.213699E−19   8.788103E−25 X4Y5 −9.196304E−22  1.613032E−22 −7.384331E−22  −1.017620E−24 −4.869993E−19   1.435145E−24 X2Y7 −8.444082E−22  4.724249E−22 1.160142E−22  5.807469E−25 −3.565433E−19   5.071171E−25 Y9 −1.391751E−24  −1.535204E−22  −1.540508E−24   3.217510E−27 −5.879640E−20  −1.515906E−26 X10 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00  0.000000E+00 X8Y2 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00  0.000000E+00 X6Y4 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00  0.000000E+00 X4Y6 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00  0.000000E+00 X2Y8 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00  0.000000E+00 Y10 0.000000E+00 0.000000E+00 0.000000E+00  0.000000E+00 0.000000E+00  0.000000E+00 Nradius   1.00E+00   1.00E+00   1.00E+00     1.00E+00   1.00E+00     1.00E+00 Y-decenter −197.752 −67.646 −76.378 −20.289 −432.652 −422.877 X-rotation  −1.837  −3.960  −2.990  −9.847  −0.659  −1.856 FIG. 13 shows a microscope lens 56 which can be used for inspecting projection masks required for projection exposure or lithography or for inspecting of exposed wafers 10 . The microscope lens images a microscope object plane or substrate plane 57 , which coincides with the image plane 8 during projection of the projection exposure installation 1 , on a microscope image plane 58 . The construction of the microscope lens 56 is similar, for example, to that of the projection object 6 in FIG. 2 , with the difference that, in the microscope lens 56 , the object and image planes are exchanged in comparison to the projection optical system 6 . The object to be analysed is therefore located at the high aperture portion of the microscope lens 56 and an image-recording device, for example a CCD camera is located at the low aperture portion of the microscope lens 56 . In the light path between the microscope image plane 58 and the substrate plane 57 , the microscope lens 56 has a total of four mirrors 59 to 62 which are numbered in this order and are also referred to as M 1 to M 4 . The third mirror 61 and the fourth mirror 62 of the microscope lens 56 correspond to the mirrors M 5 , M 6 of the previously discussed projection optical systems in terms of their design positions and the through-holes 23 , 24 . The four mirrors 59 to 62 are configured as free-form surfaces which cannot be described by a rotationally symmetrical function. Alternatively, it is also possible for at least one of the mirrors 59 to 62 to have a free-form reflection surface of this type. The first mirror 59 has negative angular magnification of the principal ray. The second mirror 60 has infinite angular magnification of the principal ray, since the principal ray 26 extends perpendicularly to the substrate plane 57 from the second mirror 60 . The angular magnifications of the principal ray of the third mirror 61 and the fourth mirror 62 are correspondingly undefined. The microscope lens 56 has a numerical aperture of 0.7. The microscope lens 56 has an intermediate image-side numerical aperture of 0.17. In the microscope lens 56 , the maximum angle of reflection α is again achieved by the outer edge rays of the mirror 57 including the through-hole 24 and is 24°. Correspondingly, the quotient of this angle of reflection and the numerical aperture is 34°. The projection optical systems 6 , 35 , 42 , 49 and the microscope lens 56 may be operated using wavelengths of the illumination or imaging light 3 other than EUV wavelengths. For example, it is also possible to use the free-form constructions for visible wavelengths. The projection optical systems 6 , 35 , 42 , 49 , the microscope lens 56 and the optical systems described in the following in relation to FIGS. 14 to 17 can be constructed in such a way that, with the exception of the light path in the region of the through-holes 23 , 24 , there is always a distance of less than 25 mm, but greater than 1 mm (e.g., greater than 5 mm) maintained between the individual rays 14 and the respective mirror M 1 to M 6 not acted upon, or 59 to 62 when acted upon by reflection of the illumination light 3 in the desired manner. This simplifies the constructional requirements of the respective optical system. FIG. 14 shows a further configuration of a projection optical system 63 which can be used in the projection exposure installation 1 , again with EUV illumination, instead of the projection optical system 6 . Components or reference quantities which correspond to those previously discussed in relation to the projection optical systems 6 , 35 , 42 , 49 of FIGS. 1 to 12 have the same reference numerals and will not be discussed in detail again. In the following only the substantial differences between the projection optical system 63 and the previously explained projection optical systems 6 , 35 , 42 , 49 will be discussed. The optical data for the projection optical system 63 are as follows: The image-side numerical aperture NA is 0.6. The dimensions of the image field 7 are 1×13 mm 2 . The reducing magnification level is 8×. The image field 7 is rectangular. The wavelength of the illumination light 3 is 13.5 nm. The projection optical system 63 has six mirrors M 1 to M 6 . The sequence of the optical effects of the mirrors M 1 to M 6 (negative N; positive P) is NPNPNP. The single intermediate image of the projection optical system 63 is present between the mirrors M 4 and M 5 . Principal rays enter the projection optical system 63 in a convergent manner from the object plane 4 . An aperture stop for limiting the illumination light at the edge is arranged on mirror M 3 . The z-distance between the object plane 4 and the image plane is 1,500 mm. The object-image shift is 7.07 mm. 5.7% of the surfaces illuminated in the pupil planes are obscured. The projection optical system 63 has a wavefront error (rms) of 0.034 in units of the wavelength of the illumination light 3 . The distortion is 15 nm. The image field curvature is 10 nm. The angle of the principal ray at the central object field point is 5.9°. The mirror M 1 has dimensions (x/y) of 126×73 mm 2 . The mirror M 2 has dimensions of 339×164 mm 2 . The mirror M 3 has dimensions of 100×96 mm 2 . The mirror M 4 has dimensions of 196×150 mm 2 . The mirror M 5 has dimensions of 307×298 mm 2 . The mirror M 6 has dimensions of 814×806 mm 2 . The sequence of the principal ray angle of incidence of the principal ray 26 of the central object field point on the mirrors M 1 to M 6 is 18.61°, 8.76°, 15.44°, 8.53°, 0.00° and 0.00°. The sequence of the maximum angle of incidence on the mirrors M 1 to M 6 is 26.60°, 11.80°, 15.98°, 12.32°, 20.14° and 5.11°. The sequence of the bandwidths of the angle of incidence on the mirrors M 1 to M 6 is 16.06°, 6.30°, 1.03°, 7.87°, less than 20.14° and less than 5.11°. The sequence of the angular magnification of the principal ray of the mirrors M 1 to M 3 (negative N; positive P) is NPN. The working distance in the object plane 4 is 102 mm. The working distance in the image plane is 40 mm. The ratio of the distance between the object plane 4 and the mirror M 1 and the distance between the object plane 4 and the mirror M 2 is 4.13. The mirrors M 1 and M 4 have a minimum distance between the used reflection surfaces and the closest imaging light path which does not act on the mirror (free board) of less than 25 mm. The distances between the pairs of mirrors M 2 -M 3 , M 4 -M 5 , M 5 -M 6 and the distance between the mirror M 6 and the image plane 8 are less than 40% of the distance between the object plane 4 and the image plane 8 . The optical design data for the reflection surfaces of the mirrors M 1 to M 6 of the projection optical system 63 can be gathered from the following tables, which correspond to the tables provided for the projection optical system 6 in accordance with FIG. 2 . Surface Radius Thickness Mode Object INFINITY 423.049 Mirror 1 291.429 −320.693 REFL Mirror 2 682.291 698.472 REFL Mirror 3 327.553 0.000 REFL STOP INFINITY −250.085 Mirror 4 398.721 909.257 REFL Mirror 5 1753.638 −620.641 REFL Mirror 6 834.258 660.641 REFL Image INFINITY 0.000 Coeff. M1 M2 M3 M4 M5 M6 K −9.797768E−01 −2.654407E−01  3.633187E+00 −2.607926E−01 3.367484E+01 3.003345E−01 Y  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 X2 −6.757907E−04 −9.897313E−05 −6.055737E−04 −1.712326E−04 8.316524E−06 3.449849E−05 Y2 −6.711750E−04 −1.286106E−04 −5.464279E−04 −1.127817E−04 1.666997E−06 3.303139E−05 X2Y −1.718471E−07  8.106102E−09  3.559721E−08 −1.625547E−07 −3.433987E−08  −5.594447E−10  Y3  8.441316E−08  2.066449E−08  2.993241E−07 −2.438542E−07 −5.340235E−09  2.648587E−10 X4 −4.235340E−10 −6.184068E−11 −1.590557E−08 −5.148175E−11 9.293663E−10 1.431375E−12 X2Y2 −2.833593E−10 −1.232739E−10 −2.294580E−08  6.076202E−11 1.884838E−09 4.501941E−12 Y4 −6.283000E−09 −1.538541E−11 −7.807703E−09  4.592939E−10 9.735975E−10 3.169895E−12 X4Y  5.216941E−13  1.355055E−14 −4.125213E−11 −5.236068E−13 −6.108177E−14  4.760532E−16 X2Y3 −5.462082E−12  1.539145E−13  5.882108E−11 −7.857103E−13 5.606699E−14 −1.383433E−15  Y5  3.841515E−11 −4.826907E−15  6.536341E−11 −1.173929E−12 6.122980E−14 −1.198686E−15  X6 −2.961655E−14 −5.649609E−16 −5.319482E−13  1.037860E−15 1.575126E−15 5.280799E−19 X4Y2 −6.986732E−15  1.523728E−17 −1.125923E−12  4.138161E−15 5.066143E−15 3.110524E−18 X2Y4  5.755669E−14 −1.992110E−16 −9.962349E−13 −5.642387E−15 5.364157E−15 3.810873E−18 Y6 −7.476803E−14 −3.652597E−17 −1.721064E−13 −2.311791E−16 1.498586E−15 9.716738E−19 X6Y  8.136042E−16  1.347989E−18  1.560712E−15 −3.431381E−17 1.006276E−18 −1.255738E−22  X4Y3  1.102636E−17  9.697709E−22  2.841374E−15 −6.361244E−17 −5.733345E−19  −1.261922E−21  X2Y5  1.331907E−16 −1.331590E−20  2.163234E−15  2.657780E−17 −1.545019E−18  −3.386914E−22  Y7  3.093492E−17  0.000000E+00  2.304330E−15  1.049058E−19 3.738255E−20 1.710371E−22 X8  1.506508E−18  5.810497E−21  1.133674E−17  6.127110E−21 3.186325E−21 1.107455E−24 X6Y2 −1.013674E−17  6.179938E−22 −5.629342E−17  3.657501E−19 2.411205E−20 2.133982E−24 X4Y4 −1.366007E−18 −3.261229E−22 −8.750490E−17  4.374764E−19 3.931624E−20 4.739463E−24 X2Y6 −1.047171E−18 −1.345299E−22 −1.260161E−17 −6.674633E−20 2.052091E−20 3.396921E−24 Y8 −9.482484E−19 −7.567828E−23 −3.447928E−18 −3.054349E−21 6.173346E−21 9.678311E−25 X8Y −5.877725E−20 −1.822355E−23 −4.253705E−19 −1.365311E−22 −1.472429E−23  2.361551E−27 X6Y3  4.790823E−20 −3.116535E−24 −6.154610E−19 −1.894833E−21 −3.675978E−23  1.990878E−27 X4Y5  8.584886E−21 −9.980946E−26  2.375768E−19 −1.854722E−21 −2.816555E−23  −4.075851E−27  X2Y7 −1.694967E−20 −4.093120E−26  7.589434E−19 −4.379199E−23 −6.563563E−24  −5.800819E−27  Y9  2.326792E−21  0.000000E+00  1.307119E−19 −2.515286E−23 2.606727E−24 −1.858737E−28  X10  1.401272E−22  6.373969E−27  2.615474E−22  2.577682E−25 4.145747E−26 −1.274796E−31  X8Y2  3.458862E−22  1.154175E−26 −7.752079E−21  5.165996E−25 1.524801E−25 −2.154682E−30  X6Y4 −6.486950E−23 −8.465791E−29 −1.437881E−20  3.499212E−24 2.916563E−25 4.867171E−30 X4Y6 −2.005656E−23 −2.584491E−28 −1.352099E−21  3.142335E−24 3.587746E−25 1.828109E−29 X2Y8  6.434247E−23 −5.536465E−29  7.452494E−21  3.871445E−25 2.307038E−25 1.576792E−29 Y10  1.692634E−24  0.000000E+00  1.578385E−21  1.350146E−25 2.372597E−26 1.664967E−30 Nradius     1.00E+00     1.00E+00     1.00E+00     1.00E+00   1.00E+00   1.00E+00 Y-decenter 72.424 −276.725 184.767 −26.657 97.145 97.828 X-rotation −3.803  24.855  1.633  24.917  0.012 −0.062 FIG. 15 shows a further configuration of a projection optical system 64 which can be used in the projection exposure installation 1 , again with EUV illumination, instead of the the projection optical system 6 . Components or reference quantities corresponding to those which have previously been explained with reference to FIG. 1 to 12 or 14 have the same reference numerals and will not be discussed in detail again. The optical data of the projection optical system 64 are summarised in the following: The image-side numerical aperture NA is 0.7. The dimensions of the image field 7 are 1×13 mm 2 . The reducing magnification level is 8×. The image field 7 is rectangular. The wavelength of the illumination light 7 is 13.5 nm. The projection optical system 64 has six mirrors M 1 to M 6 . The sequence of the optical effects of the mirrors M 1 to M 6 (negative N; positive P) is NPNPNP. The single intermediate image plane of the projection optical system 64 is present between the mirrors M 4 and M 5 . Principal rays enter the projection optical system 64 in a convergent manner from the object plane 4 . An aperture stop for limiting the illumination light at the edge is arranged on mirror M 3 . The z-distance between the object plane 4 and the image plane 8 is 1,483 mm. The object-image shift is 13.86 mm. 6.4% of the surfaces illuminated in the pupil planes are obscured. The projection optical system 64 has a wavefront error (rms) of 0.062 in units of the wavelength of the illumination light 3 . The distortion is 18 nm. The image field curvature is 10 nm. The angle of the principal ray at the central object field point is 5.9°. The mirror M 1 has dimensions (x/y) of 134×84 mm 2 . The mirror M 2 has dimensions of 365×174 mm 2 . The mirror M 3 has dimensions of 121×114 mm 2 . The mirror M 4 has dimensions of 220×176 mm 2 . The mirror M 5 has dimensions of 363×354 mm 2 . The mirror M 6 has dimensions of 956×952 mm 2 . The sequence of the principal ray angle of incidence of the principal ray 26 of the central object field point on the mirrors M 1 to M 6 is 20.86°, 10.26°, 17.50°, 9.84°, 0.00° and 0.00°. The sequence of the maximum angle of incidence on the mirrors M 1 to M 6 is 29.83°, 13.67°, 18.09°, 14.40°, 24.60° and 5.70°. The sequence of the bandwidths of the angle of incidence on the mirrors M 1 to M 6 is 18.23°, 7.18°, 1.06°, 9.50°, less than 16.98° and less than 5.51°. The sequence of the angular magnification of the principal ray of the mirrors M 1 to M 3 (negative N; positive P) is NPN. The working distance in the object plane 4 is 100 mm. The working distance in the image plane 8 is 40 mm. The ratio of the distance between the object plane and the mirror M 1 and the distance between the object plane 4 and the mirror M 2 is 4.13. The mirrors M 1 and M 4 have a minimum distance between the used reflection surface and the closest imaging light path not acting upon the mirrors (free board) of less than 25 mm. The distances between the pairs of mirrors M 2 -M 3 , M 4 -M 5 , M 5 -M 6 and the distance between the mirror M 6 and the image plane 8 are greater than 40% of the distance between the object plane 4 and the image plane 8 . The optical design data for the reflection surfaces of the mirrors M 1 to M 6 of the projection optical system 64 can be inferred from the following tables, which correspond to the tables provided for the projection optical system 6 according to FIG. 2 . Surface Radius Thickness Mode Object INFINITY 413.264 Mirror 1 289.172 −313.264 REFL Mirror 2 680.603 689.549 REFL Mirror 3 333.217 0.000 REFL STOP INFINITY −255.285 Mirror 4 400.498 908.331 REFL Mirror 5 1757.579 −620.526 REFL Mirror 6 834.338 660.526 REFL Image INFINITY 0.000 Coeff. M1 M2 M3 M4 M5 M6 K −1.030576E+00 −2.635304E−01  4.190202E+00 −2.532242E−01 3.343958E+01 2.989093E−01 Y  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 0.000000E+00 0.000000E+00 X2 −6.535480E−04 −9.651094E−05 −6.315149E−04 −1.860891E−04 6.210957E−06 3.467308E−05 Y2 −6.703313E−04 −1.285085E−04 −5.894828E−04 −1.055800E−04 3.848982E−07 3.293719E−05 X2Y −1.109153E−07  9.418989E−09  5.191842E−07 −1.736028E−07 −3.604297E−08  −1.901465E−09  Y3 −1.849968E−07  1.804370E−08  1.052875E−08 −3.008104E−07 −1.255871E−08  −7.306681E−10  X4 −3.455652E−10 −6.435672E−11 −1.959503E−08 −1.181975E−10 9.251123E−10 9.219996E−13 X2Y2  8.907151E−11 −1.169230E−10 −2.854507E−08  3.223161E−11 1.828013E−09 3.292930E−12 Y4 −6.694084E−09 −1.746102E−11 −1.100719E−08  5.508116E−10 9.590508E−10 2.723624E−12 X4Y −6.682583E−13  6.169836E−15 −4.579394E−11 −4.554803E−13 −1.075058E−13  −9.398044E−17  X2Y3 −3.764773E−12  1.837427E−13  8.072483E−13 −1.108837E−12 1.733346E−14 −1.372960E−15  Y5  3.946729E−11  1.501209E−15  4.522011E−11 −1.761285E−12 5.059303E−14 −1.418313E−15  X6 −2.950759E−14  5.555342E−16 −4.772179E−13  2.049340E−16 1.249728E−15 6.302080E−19 X4Y2 −3.981976E−14  7.309283E−17 −1.369581E−12  2.599849E−15 4.180701E−15 1.406199E−18 X2Y4  6.662007E−14 −1.567936E−16 −1.344358E−12 −6.991042E−15 4.324958E−15 9.589967E−19 Y6 −6.296271E−14  5.254697E−18 −3.274586E−13 −1.365187E−15 1.317067E−15 4.531531E−19 X6Y  9.572567E−16 −4.550481E−18 −2.349696E−17 −2.327425E−17 1.147404E−18 −5.815673E−22  X4Y3  1.729544E−15 −5.168321E−21 −6.343836E−16 −6.844084E−17 1.396280E−18 −1.101533E−21  X2Y5  2.003151E−16 −1.086056E−20  7.211912E−17  3.651614E−17 2.129037E−19 −6.825077E−22  Y7 −6.259873E−17  0.000000E+00  1.314567E−15  4.966906E−18 4.944608E−20 −3.674224E−22  X8  8.514832E−19  5.499001E−21 −1.315946E−17  1.431441E−20 5.935619E−21 2.351396E−25 X6Y2 −1.930952E−17  1.021410E−20 −3.809772E−17  2.893679E−19 2.146809E−20 1.941034E−24 X4Y4 −2.629657E−17 −5.261250E−22 −4.023107E−17  4.708584E−19 2.844557E−20 3.285122E−24 X2Y6 −7.113538E−18 −2.063344E−22 −3.710671E−17 −1.202904E−19 1.718587E−20 6.947595E−25 Y8 −6.688170E−19 −9.807129E−23 −1.246348E−17 −1.007426E−20 5.947625E−21 5.352899E−25 X8Y −2.167642E−20 −1.475245E−23 −4.375451E−20 −3.593805E−22 −6.272355E−24  −6.386618E−29  X6Y3  1.577014E−19 −7.541034E−24  1.407216E−21 −1.733010E−21 −1.503182E−23  −2.378905E−27  X4Y5  1.475476E−19  2.828164E−25  2.164416E−19 −1.819583E−21 −5.558949E−24  −4.818316E−27  X2Y7  2.386767E−20  2.916090E−26  4.037031E−19  1.506408E−22 1.500592E−23 −2.782420E−27  Y9  2.686189E−21 −3.808616E−26  1.365101E−19  2.759985E−23 9.373049E−24 3.697377E−29 X10  6.880195E−23  4.028878E−27 −3.684363E−22  3.684053E−25 8.977447E−27 1.376079E−31 X8Y2  1.028653E−22  7.179210E−27 −5.946953E−21  1.412893E−24 6.817863E−26 −3.343096E−30  X6Y4 −4.423830E−22 −2.428875E−28 −1.431825E−20  3.370257E−24 1.794556E−25 −8.790772E−30  X4Y6 −2.798064E−22  1.268239E−28 −9.083451E−21  2.674694E−24 2.401259E−25 −2.285964E−30  X2Y8 −1.113049E−23 −1.289425E−30  4.131039E−22 −1.824536E−27 1.599496E−25 5.901778E−30 Y10  1.536113E−24  0.000000E+00  9.866128E−22  9.363641E−28 1.894848E−26 1.501949E−30 Nradius     1.00E+00     1.00E+00     1.00E+00     1.00E+00   1.00E+00   1.00E+00 Y-decenter 76.368 −281.911 194.003 −24.759 94.122 96.437 X-rotation −6.675  24.349  2.204  25.034 −0.109 −0.453 In the following more optical data for two further microscope lenses 65 , 66 are summarised which, like the microscope lens 56 , can be used for inspecting projection masks required for projection exposure or lithography or for inspecting exposed wafers. Both of these further microscope lenses 65 , 66 are shown in FIGS. 16 and 17 . The basic four-mirror construction of the two further microscope lens 65 , 66 corresponds to that of FIG. 13 . Components in these further microscope lenses 65 , 66 , which correspond to those which have previously been explained in relation to the microscope lens 56 , have the same reference numerals or designations. The first of the two further microscope lenses 65 , 66 , the microscope lens 65 , shown in FIG. 16 , has an object-side numerical aperture of 0.8. The dimensions of the square object field are 0.8×0.8 mm 2 . The increasing magnification level is 10×. The wavelength of the illumination light 3 is 193.0 nm. Other illumination light wavelengths are also possible, for example a visible wavelength or an EUV wavelength. The sequence of the optical effects of the mirrors M 1 to M 4 (negative N; positive P) is NPNP. The single intermediate image is located between the mirrors M 2 and M 3 at the location of the through-hole 23 in the mirror M 4 . Principal rays travel out of the microscope lens 65 in a divergent manner from the microscope image plane 58 . The z-distance between the substrate plane 57 and the image plane 58 is 1,933 mm. The object-image shift is 477 mm. 21.5% of the illuminated surfaces in the pupil planes are obscured. The microscope lens 65 has a wavefront error (rms) of 0.004 in units of the wavelength of the illumination light 3 . The angle of the principal ray at the central object field point is 13.8°. The mirror M 1 has dimensions (x/y) of 219×216 mm 2 . The mirror M 2 has dimensions of 520×502 mm 2 . The mirror M 3 has dimensions of 202×189 mm 2 . The mirror M 4 has dimensions of 742×699 mm 2 . The sequence of the principal ray angle of incidence of the principal ray 26 of the central object field point on the mirrors M 1 to M 4 is 10.48°, 3.53°, 0.04° and 0.02°. The sequence of the maximum angle of incidence on the mirrors M 1 to M 4 is 15.70°, 5.58°, 27.79° and 3.19°. The sequence of the bandwidths of the angle of incidence on the mirrors M 1 to M 4 is 11.93°, 4.46 °, 27.79° and 3.19°. The working distance in the microscope image plane 58 is 240 mm. The working distance in the substrate plane 57 is 40 mm. The ratio of the distance between the microscope image plane 58 and the mirror M 1 and the distance between the microscope image plane 58 and the mirror M 2 is 5.63. The distance between the substrate plane 57 and the mirror M 1 and the distances between the pairs of mirrors M 1 -M 2 and M 2 -M 3 are greater than 40% of the distance between the substrate plane 57 and the image plane 58 . The optical design data for the reflection surfaces of the mirrors M 1 to M 4 of the microscope lens 65 can be gathered from the following tables, which correspond to the tables for the previously described projection optical systems. In these tables “object” refers to the microscope image plane 58 . “Image” refers to the substrate plane 57 . Surface Radius Thickness Mode Object INFINITY 1350.229 Mirror 1 240.546 −1110.493 REFL Mirror 2 435.560 1653.485 REFL Mirror 3 756.829 −422.992 REFL Mirror 4 530.970 462.991 REFL Image INFINITY 0.000 Coefficient M1 M2 M3 M4 K −1.387402E+00 −9.186277E−01  2.479623E+01  1.846234E−01 Y  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X2 −1.972513E−03 −8.152652E−04  4.304599E−04  3.443510E−05 Y2 −2.046135E−03 −8.219532E−04  4.280214E−04  3.442623E−05 X2Y  4.924422E−07  1.043274E−08  1.420911E−07 −1.467857E−09 Y3  3.892760E−07  1.233789E−08  1.433179E−07 −1.285787E−09 X4  2.843271E−09 −8.849537E−11  5.644150E−09  5.790124E−12 X2Y2  6.307229E−09 −1.868473E−10  1.095525E−08  1.192799E−11 Y4  3.357640E−09 −9.886660E−11  5.323173E−09  6.015673E−12 X4Y  3.303637E−13  1.821786E−14 −9.065558E−13  2.636707E−15 X2Y3  4.517153E−13  3.654773E−14 −1.999032E−12  4.573973E−15 Y5 −1.472281E−14  1.913697E−14 −1.039223E−12  1.907361E−15 X6 −1.567647E−14 −2.778349E−17  3.227077E−14  6.941174E−18 X4Y2 −4.271994E−14 −8.658416E−17  9.037002E−14  1.569376E−17 X2Y4 −3.766656E−14 −8.931045E−17  8.435334E−14  1.111043E−17 Y6 −1.062731E−14 −3.096033E−17  2.620546E−14  2.369368E−18 X6Y  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X4Y3  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X2Y5  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 Y7  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X8  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X6Y2  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X4Y4  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X2Y6  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 Y8  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X8Y  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X6Y3  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X4Y5  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X2Y7  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 Y9  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X10  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X8Y2  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X6Y4  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X4Y6  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X2Y8  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 Y10  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 Nradius  1.000000E+00  1.000000E+00  1.000000E+00  1.000000E+00 Y-decenter −419.012 −607.162 −478.467 −476.646 X-rotation  −2.721    8.467    0.209  −0.024 The optical data for the second microscope lens 66 , which is shown in FIG. 17 and can also be used instead of the microscope lens 56 in FIG. 13 , are summarised in the following; The object-side numerical aperture NA is 0.8. The dimensions of the square object field are 0.8×0.8 mm 2 . The increasing magnification level is 40×. The wavelength of the illumination light 3 is 193.0 nm. Other illumination light wavelengths may also be used, for example visible or EUV wavelengths. The sequence of the optical effects of the mirrors M 1 to M 4 (negative N; positive P) is NPNP. The single intermediate image is located between the mirrors M 2 and M 3 in the region of the through-hole 23 in the mirror M 4 . On the image-side, principal rays travel out of the microscope lens 66 in a divergent manner. The z-distance between the substrate plane 57 and the image plane 58 is 2,048 mm. The object-image shift is 522 mm. 24.6% of the surfaces illuminated in the pupil planes are obscured. The microscope lens 66 has a wavefront error (rms) of 0.016 in units of the wavelength of the illumination light 3 . The angle of the principal ray at the central object field point is 17.1°. The mirror M 1 has dimensions (x/y) of 59×58 mm 2 . The mirror M 2 has dimensions of 222×197 mm 2 . The mirror M 3 has dimensions of 180×163 mm 2 . The mirror M 4 has dimensions of 736×674 mm 2 . The sequence of the principal ray angle of incidence of the principal ray 26 of the central object field point to the mirrors M 1 to M 4 is 12.23°, 3.81°, 0.10° and 0.14°. The sequence of the maximum angle of incidence on the mirrors M 1 to M 4 is 18.94°, 5.66°, 24.95° and 2.75°. The sequence of the bandwidths of the angle of incidence on the mirrors M 1 to M 4 is 10.17°, 1.81°, 24.95° and 2.75°. The working distance in the microscope image plane 58 is 996 mm. The working distance in the substrate plane 57 is 40 mm. The ratio of the distance between the microscope image plane 58 and the mirror M 1 and the distance between the microscope image plane 58 and the mirror M 2 is 1.46. The distance between the substrate plane 57 and the mirror M 1 and the distance between the pair of mirrors M 2 -M 3 is less than 40% of the distance between the substrate plane 57 and the image plane 58 . The optical design data for the reflection surfaces of the mirrors M 1 to M 4 of the microscope lens 66 can be gathered from the following tables, which correspond to the tables for the previously described microscope lens 65 . Surface Radius Thickness Mode Object INFINITY 1458.431 Mirror 1 138.358 −462.391 REFL Mirror 2 352.350 1011.807 REFL Mirror 3 521.060 −429.417 REFL Mirror 4 523.773 469.415 REFL Image INFINITY 0.000 Coefficient M1 M2 M3 M4 K  2.186021E−01 −8.967130E−01  1.353344E+01  1.426428E−01 Y  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X2 −2.119566E−03 −6.122040E−04  3.598902E−04  2.150055E−05 Y2 −1.870353E−03 −6.339662E−04  4.023778E−04  2.187467E−05 X2Y −2.390768E−05  6.494155E−08 −2.453628E−07  3.235225E−09 Y3 −2.981028E−05  5.780210E−08 −6.744637E−08  4.604016E−09 X4  1.923306E−08  2.795937E−10  2.925492E−09 −1.313710E−12 X2Y2  4.121148E−07  5.095698E−10  1.819466E−09 −5.092789E−12 Y4  4.757534E−07  2.387275E−10 −6.547683E−10 −2.809211E−12 X4Y −1.446899E−09  5.301791E−13 −9.735433E−12 −3.703196E−15 X2Y3 −7.970490E−09  8.235778E−13 −4.591548E−11 −1.311139E−14 Y5 −6.911626E−09  5.427574E−13 −3.434264E−11 −8.056144E−15 X6 −6.957804E−12  4.031055E−16  4.869018E−14 −2.032419E−18 X4Y2 −6.520224E−12  3.388642E−15  1.730353E−13 −5.277652E−18 X2Y4  5.785767E−11  4.106532E−15  8.768509E−14 −5.976002E−18 Y6  5.002226E−11 −2.665419E−15 −1.533312E−14  3.256782E−19 X6Y  3.978450E−14 −3.458637E−18  2.808257E−16 −2.974086E−21 X4Y3  1.060921E−15 −5.135846E−18  1.062927E−15 −1.985462E−20 X2Y5 −2.907745E−13  1.367522E−17  1.248668E−15 −1.673351E−20 Y7 −1.895272E−13  2.948597E−17  4.722358E−16 −2.273773E−22 X8  0.000000E+00  9.742461E−21 −1.224565E−19 −5.498909E−24 X6Y2  0.000000E+00 −1.149790E−22 −8.469691E−19 −3.121995E−23 X4Y4  0.000000E+00 −3.605842E−20 −9.612391E−19 −9.354588E−23 X2Y6  0.000000E+00 −8.956173E−20  3.862422E−20 −1.029099E−22 Y8  0.000000E+00 −6.962503E−20  1.096441E−19 −3.729022E−23 X8Y  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X6Y3  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X4Y5  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X2Y7  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 Y9  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X10  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X8Y2  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X6Y4  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X4Y6  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 X2Y8  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 Y10  0.000000E+00  0.000000E+00  0.000000E+00  0.000000E+00 Nradius  1.000000E+00  1.000000E+00  0.000000E+00  0.000000E+00 Y-decenter −473.594 −625.447 −517.418 −517.782 X-rotation  −2.590  13.500  −1.408  −0.608 Other embodiments are in the claims.

The disclosure generally relates to imaging optical systems that include a plurality of mirrors, which image an object field lying in an object plane in an image field lying in an image plane, where at least one of the mirrors has a through-hole for imaging light to pass through. The disclosure also generally relates to projection exposure installations that include such im-aging optical systems, methods of using such projection exposure installa-tions, and components made by such methods.

FIELD OF THE INVENTION [0001] The present invention relates to semiconductor memory device manufacturing, and more particular to methods of forming dual workfunction high-performance support MOSFETs (metal oxide semiconductor field effect transistors) in an EDRAM (embedded dynamic random access memory) array. BACKGROUND OF THE INVENTION [0002] Embedded DRAM applications demand both the utmost in high-performance CMOS (complementary metal oxide semiconductor) logic devices and high-density DRAM arrays. High-performance CMOS logic devices require low-resistance (on the order of 5 ohms/sq. or below) gate conductors and source/drain diffusions (salicidation), which drive processes that are costly and difficult to integrate with high-density DRAM processes. For example, salicided gates and source/drain regions greatly complicate the processes for forming array MOSFETs since the array MOSFETs need bitline contacts which are borderless to adjacent wordline conductors; also, salicided junctions in the array may result in increased current leakage of the memory device. [0003] In a typical DRAM array, the wordlines need to be capped with an insulator, while in the supports the gate conductors must be exposed to allow the introduction of dual workfunction doping and salicidation. Conventional solutions to these integration problems require additional masking steps to remove the insulating gate cap from the support MOSFETs prior to the salicidation process. [0004] Another problem encountered in prior art processes is the lithography steps used to simultaneously form support gates and wordlines: optimization of support gate lithography results in difficulties with defining wordlines in the array which are on a 2 F pitch. [0005] Yet another problem with prior art processes is in the formation of local interconnects. Specifically, in the prior art one of the metallization levels, i.e., the M 0 level, is used for both the bitline and for forming local interconnects. In the present invention, the conventional M 0 metal is not required since the bitlines and local interconnects are formed by the salicidation of polysilicon. [0006] In view of the drawbacks mentioned hereinabove with prior art processes of forming dual workfunction high-performance support MOSFETs in EDRAM arrays, there is a need for developing new and improved methods of manufacturing the same. That is, new and improved methods are needed for integrating high-performance CMOS logic devices with dense array MOSFET DRAM cells. SUMMARY OF THE INVENTION [0007] One object of the present invention is to provide a method of manufacturing a dual workfunction high-performance support MOSFET/EDRAM array in which the need for additional masking steps to form the high-performance CMOS logic devices and borderless contacts are eliminated. [0008] A further object of the present invention is to provide a method of manufacturing a dual workfunction high-performance support MOSFET/EDRAM array wherein the method does not share support gate conductor lithography with wordline lithography. [0009] A still further object of the present invention is to provide a method of manufacturing a dual workfunction high-performance support MOSFET/EDRAM array wherein the gate conductor lithography is shared with the array bitline lithography step. Sharing of a single masking step for the support gate conductor and array bitlines results in the saving of a deep—UV mask and is less demanding due to its 3 F pitch. [0010] A yet further object of the present invention is to provide a method of manufacturing a dual workfunction high-performance support MOSFET/EDRAM array which does not use an M 0 level for the local interconnect. [0011] Another object of the present invention is to provide a dual workfunction high-performance support MOSFET/EDRAM array in which a gate conductor guard ring is formed around the array region of the structure so as to avoid trapping of a stringer of polysilicon in the isolation region. The presence of the guard ring provides an internal protection scheme, which prevents the designer from placing a gate conductor across the isolation region. [0012] An even further object of the present invention is to provide a dual workfunction high-performance support MOSFET/EDRAM array comprising a local interconnect which is formed concurrently, and of the same low-resistance material, as the gate conductor in the array region. [0013] These and other objects and advantages are achieved in the present invention by employing one of the following three processing schemes which are each capable of integrating high-performance CMOS logic devices with dense array MOSFET DRAM cells. It should be noted that the present invention contemplates the formation of vertical and planar MOSFET arrays, with vertical MOSFET arrays being more preferable than planar MOSFET arrays. Therefore, although the following is specific to vertical MOSFET arrays, the processing steps used each of the three embodiments can be used in making planar MOSFET arrays. [0014] In accordance with a first embodiment of the present invention, a process of forming a dual workfunction high-performance support MOSFET/EDRAM vertical (or planar) array memory structure having a gate conductor guard ring formed around the array region is provided. The gate conductor guard ring is a consequence of a groundrule that guarantees that a strip of gate conductor polysilicon remains above the isolation region surrounding the array. [0015] Specifically, the first embodiment of the present invention comprises the steps of: [0016] (a) providing a memory structure having at least one array region and at least one support region, wherein said at least one array region and said at least one support region are separated by an isolation region, wherein said at least one array region includes a plurality of dynamic random access memory (DRAM) cells embedded in a substrate, wherein adjacent DRAM cells are connected to each other through bitline diffusion regions which are capped with an oxide capping layer; [0017] (b) forming a patterned nitride layer on all exposed surfaces in said at least one array region and on a portion of said isolation region; [0018] (c) forming a gate oxide on said substrate in said at least one support region; [0019] (d) forming a stack comprising a first polysilicon layer and a dielectric capping layer on all exposed surfaces of said memory structure; [0020] (e) removing said dielectric capping layer, said first polysilicon layer and said nitride layer from said at least one array region; [0021] (f) forming wordlines over said plurality of DRAM cells in said at least one array region; [0022] (g) forming spacers on exposed sidewalls of said wordlines in said at least one array region as well as on exposed sidewalls of said stack remaining in said structure; [0023] (h) forming a block mask over the at least one support region and at least a portion of one of said DRAM cells that is adjacent to said isolation region, whereby said block mask does not cover said oxide capping layer; [0024] (i) removing said oxide capping layer over said bitline diffusion regions and stripping said block mask; [0025] (j) forming a patterned second polysilicon layer over the at least one array region and said stack which is present on said isolation region, and removing said dielectric capping layer in said at least one support region; [0026] (k) forming a doped glass material layer over all surfaces in said at least one array region and said at least one support region; [0027] (l) patterning said doped glass material layer so as to form hard masks in said at least one array region and said at least one support region, whereby said hard mask in said at least one array region defines a bitline of the memory structure and said hard mask in said at least one support region defines a support gate region; [0028] (m) removing exposed second polysilicon layer from said at least one array region and said isolation region, while simultaneously removing exposed portions of said first polysilicon layer in said at least one support region, whereby a gate conductor guard ring is formed on said isolation region and said support gate region is formed in said at least one support region; [0029] (n) removing said hard masks from said at least one array region and from said at least one support region and forming a screen oxide layer on any exposed silicon surfaces; [0030] (o) forming source and drain regions about said support gate region; and [0031] (p) removing oxide overlying said bitline, support gate region, and source and drain regions so as to expose silicon surfaces and saliciding the exposed silicon surfaces so as to provide salicide regions over said bitline, said gate region and said source and drain regions. [0032] A further processing step of the first embodiment of the present invention includes forming a patterned dielectric having via openings overlying the memory structure provided in step (p) above. The via openings allow for the formation of contacts to the support gate region. [0033] In a second embodiment of the present invention, an array/support transition region, which does not contain a gate conductor guard ring over the isolation region around the perimeter of the array, is provided. In this embodiment, the block mask used to protect areas outside of the array during the removal of the oxide layer in the first embodiment is eliminated. Furthermore, the dielectric cap protecting the support polysilicon is removed early in this embodiment. These changes result in improved planarity, eliminating the need for planarizing the doped glass layer. Thus, the support gate stack height, which needs to be patterned, is significantly reduced resulting in improved linewidth control. [0034] The second embodiment of the present invention comprises the steps of: [0035] (a) providing a memory structure having at least one array region and at least one support region, wherein said at least one array region and said at least one support region are separated by an isolation region, wherein said at least one array region includes a plurality of dynamic random access memory (DRAM) cells embedded in a substrate, wherein adjacent DRAM cells are connected to each other through bitline diffusion regions which are capped with an oxide capping layer; [0036] (b) forming a patterned nitride layer on all exposed surfaces in said at least one array region and on a portion of said isolation region; [0037] (c) forming a gate oxide on said substrate in said at least one support region; [0038] (d) forming a stack comprising a first polysilicon layer and a dielectric capping layer on all exposed surfaces of said memory structure; [0039] (e) removing said dielectric capping layer, said first polysilicon layer and said nitride layer from said at least one array region; [0040] (f) forming wordlines over said plurality of DRAM cells in said at least one array region; [0041] (g) forming spacers on exposed sidewalls of said wordlines in said at least one array region as well as on exposed sidewalls of said stack remaining in said structure; [0042] (h) anisotropically etching said memory structure so as to remove said oxide capping layer thereby exposing said bitline diffusion regions in said at least one array region, while simultaneously removing said dielectric capping layer over said isolation region and in said at least one support region; [0043] (i) depositing an undoped layer of polysilicon over all exposed surfaces of said memory structure; [0044] (j) patterning said undoped layer of polysilicon so as to simultaneously form a bitline in said at least one array region and a gate region in said at least one support region; [0045] (k) forming a screen oxide layer on any exposed silicon surfaces; [0046] (l) forming sidewall spacers about said gate region; [0047] (m) forming source and drain regions about said gate region; and [0048] (n) removing oxide overlying said bitline, gate region, and source and drain regions so as to expose silicon surfaces and saliciding said exposed silicon surfaces so as to provide salicide regions over said bitline, said gate region and said source and drain regions. [0049] A further processing step of the second embodiment of the present invention includes forming a patterned dielectric having via openings overlying the memory structure provided in step (n) above. The via openings allow for the formation of contacts to the support gate region. [0050] The third embodiment of the present invention provides a method for forming a local interconnect wiring level in a dual workfunction high-performance MOSFET/EDRAM array. Specifically, the third embodiment of the present invention comprises the steps of: [0051] (a) providing a memory structure having at least one array region and at least one support region, wherein said at least one array region and said at least one support region are separated by an isolation region, wherein said at least one array region includes a plurality of dynamic random access memory (DRAM) cells embedded in a substrate, wherein adjacent DRAM cells are connected to each other through bitline diffusion regions which are capped with an oxide capping layer; [0052] (b) forming a patterned nitride layer on all exposed surfaces in said at least one array region and on a portion of said isolation region; [0053] (c) forming a gate oxide on said substrate in said at least one support region; [0054] (d) forming a stack comprising a first polysilicon layer and a dielectric capping layer on all exposed surfaces of said memory structure; [0055] (e) removing said dielectric capping layer, said first polysilicon layer and said nitride layer from said at least one array region and a portion of said at least one support region; [0056] (f) doping a portion of said substrate in said support region so as to form a diffusion region for subsequent formation of a local interconnect contact thereon; [0057] (g) forming wordlines over said plurality of DRAM cells in said at least one array region, while simultaneously forming a local interconnect in said at least one support region above said diffusion region, wherein said wordlines and said local interconnect are composed of the same material; [0058] (h) forming spacers on exposed sidewalls of said wordlines in said at least one array region, and said local interconnect and remaining stack in said at least one support region, said remaining stack defining a support gate region of said structure; [0059] (i) removing any exposed oxide over said bitline diffusion regions; [0060] (j) forming a patterned second polysilicon layer over the at least said at least one array region and said stack which is overlaying said isolation region, and removing said dielectric capping layer in said at least one support region; [0061] (k) forming a doped glass material layer over all surfaces in said at least one array region and said at least one support region; [0062] (l) patterning said doped glass material layer so as to form a hard mask in said at least one array region, whereby said hard mask in said at least one array region defines a bitline of the memory structure; [0063] (m) removing said hard mask from said at least one array region and forming an oxide layer on all exposed silicon surfaces; [0064] (n) forming source and drain regions about said gate region; and [0065] (p) removing oxide overlying said bitline, support gate region, and source and drain regions so as to expose said silicon surfaces and saliciding said silicon surfaces so as to provide salicide regions over said bitline, said support gate region and said source and drain regions. [0066] A further processing step of the third embodiment of the present invention includes forming a patterned dielectric having via openings overlying the memory structure provided in step (p) above. The via openings allow for the formation of contacts to the support gate region. [0067] In addition to the above methods, the present invention also contemplates various dual workfunction high-performance support MOSFET/EDRAM array. In one memory structure of the present invention, a guard ring is present around the array region. In another memory cell of the present invention, a local interconnect, which is composed of the same material as that of the wordline, is provided. In yet another memory structure of the present invention, vertical DRAMs are present. In an even further embodiment of the present invention, planar DRAMs are present. BRIEF DESCRIPTION OF THE DRAWINGS [0068] [0068]FIGS. 1-12 are pictorial views illustrating the processing steps that are employed in the first embodiment of the present invention. [0069] [0069]FIGS. 13-20 are pictorial views illustrating the processing steps that are employed in the second embodiment of the present invention. [0070] [0070]FIGS. 21-27 are pictorial views illustrating the processing steps that are employed in the third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION [0071] The present invention which provides various processes of forming dual workfunction high-performance support DRAMs/EDRAM arrays will now be described in more detail by referring to the drawings that accompany the present application. It should be noted that in the accompanying drawings, like reference numerals are used for describing like and corresponding elements. [0072] Reference is first made to FIGS. 1-12 which illustrate the various processing steps employed in a first embodiment of the present invention. In the first embodiment, a gate conductor guard ring is formed around the array region as a consequence of a groundrule which guarantees that a strip of gate conductor polysilicon remains above a shallow trench isolation ring surrounding the array. FIG. 1 illustrates an initial memory structure 10 that can be employed in the present invention. Specifically, the initial memory structure shown in FIG. 1 comprises an array region 12 and a support region 14 . It is noted that although the drawings depicted the presence of only one of each region in the structure, the memory structure may include any number of array regions and support regions therein. Moreover, it is again noted that although the drawings and text are specific for vertical DRAMs, the present invention works equal well for planar DRAMs. As illustrated, array region 12 is separated from support region 14 by isolation region 16 . In accordance with the present invention, the isolation region includes a surface step region 17 which is formed during the fabrication of the same. Although the drawings depict the isolation region as a shallow trench isolation (STI) region the invention is not limited to just STI regions. Instead, other means of electrically separating the array region from the support region such as LOCOS (local oxidation of silicon) are also contemplated herein. [0073] The array region of FIG. 1 includes a plurality of vertical DRAMs 20 , two of which are shown, in the drawing, embedded in substrate 18 . The substrate includes, but is not limited to: any semiconducting material such as Si, SiGe, GaAs, InAs and other like semiconductors. Layered semiconductors such as Si/SiGe and Silicon-On-Insulators (SOIs) are also contemplated herein. The substrate in the array region may also include a well region which is formed utilizing conventional ion implantation. For clarity, the array well region is not shown in the drawings of the present invention. [0074] Array region 12 also includes a bitline diffusion region 22 which is formed in semiconductor substrate 18 between two adjacent vertical DRAMs. In accordance with the present invention, the bitline diffusion region serves to electrically connect the two DRAM cells shown in FIG. 1 together. On top of the bitline diffusion as well as other exposed surfaces of the semiconductor substrate is a layer of oxide 24 which is referred to hereinafter as the top trench oxide or TTO for short. As shown, TTO layer 24 is formed on the upper portion of the semiconductor substrate which does not include the DRAMs. [0075] Each DRAM includes a gate conductor 30 formed in the top portion of a deep trench and deep trench polysilicon 32 which is formed in the lower portion of the deep trench. Separating the gate conductor and the deep trench polysilicon is a trench oxide layer 34 . Each DRAM shown in FIG. 1 also includes a collar region 36 and a buried out-diffused strap region 38 . It is noted that the vertical DRAM cells of the present invention may include other elements that are well known to those skilled in the art, but for clarity, those other elements are not shown in the drawings of the present invention. Also, the present invention is not limited to the exact memory structure shown in FIG. 1. That is, the DRAM cells may also include a buried exterior counterelectrode about the trench, or a counterelectrode formed inside the trench and a node dielectric formed on said counterelectrode. Deep trench polysilicon is formed on the node dielectric. Other memory structures which include the above basic elements, but having a different configuration are also contemplated herein [0076] The memory structure shown in FIG. 1 is fabricated utilizing conventional processing techniques that are well known to those skilled in the art. Since such processing steps are well known, a detailed description of the same is not provided herein [0077] [0077]FIG. 2 illustrates the memory structure after various layers have been formed in the support and array regions. Specifically, the memory structure of FIG. 2 includes a patterned nitride layer 40 which is formed on a top surface of the structure in the array region. As shown, a portion of nitride layer 40 is also present on the isolation region. The structure of FIG. 2 also includes a first layer of polysilicon 42 and a dielectric capping layer 44 which are formed on top of the entire structure in both the array and support regions. It is also possible to have a combination of dielectrics for layer 44 to simplify further processing. For example, dielectric 44 can be a layer of tetraethylorthosilicate (TEOS) capped with SiN. It is noted that the structure of FIG. 2 also includes a support well that is formed in the substrate utilizing conventional ion implantation. Like the previous mentioned array well, the support well is not defined in the drawings of the present invention. [0078] The processing steps which are employed in the present invention for forming the structure shown in FIG. 2 will now be described in some detail. First, nitride layer 40 is deposited on both the array and support surfaces utilizing a conventional deposition processes such as chemical vapor deposition (CVD), plasma-assisted CVD, chemical solution deposition, sputtering or other like deposition processes. The thickness of this nitride layer may vary and is not critical to the present invention. The nitride layer is then opened in the support region by forming a photoresist mask, not shown, over the nitride layer in the array region, and thereafter etching the exposed nitride layer in the support region. A sacrificial oxide layer, not shown, is then grown in the support region utilizing a conventional thermal growing process. It is noted that the sacrificial oxide layer serves as an implantation mask for the forming the support well region. The support well is then formed by utilizing a conventional ion implantation process and thereafter the sacrificial oxide layer is removed utilizing a conventional etching process. Support gate oxide or gate dielectric 46 is then formed by a conventional process or thermally in the support region. The equivalent oxide thickness of the support gate oxide or gate dielectric is from about 1.0 to about 15 nm. [0079] After stripping the photoresist covering the array region, first layer of polysilicon 42 is then deposited utilizing a conventional deposition process such as CVD, plasma-assisted CVD, sputtering, spin-on coating or other like deposition processes. The thickness of the first polysilicon layer may vary depending on the deposition process employed in forming the same, but typically it has a thickness of from about 10 to about 200 nm. [0080] Dielectric capping layer 44 , which may comprise TEOS or another like dielectric material, is then formed on the first polysilicon layer utilizing a conventional deposition process such as CVD. It is also preferable to have a layer of SiN overlying the TEOS layer. [0081] Next, and as shown in FIG. 3, a conventional mask 50 is employed to remove the dielectric capping layer and first polysilicon layer from the array region and thereafter nitride layer 40 is removed in the array region utilizing an etching process that is selective to oxide and silicon. It is noted that the dielectric capping and polysilicon layers are removed by utilizing a conventional lithography and a conventional etching step or a combination of steps which is (are) capable of stopping on the nitride layer. [0082] A wordline stack which may comprise a W/WN or another metal conductor 54 capped by SiN or another dielectric material 56 are deposited in the array region and then patterned to form wordlines 52 . It should be noted that although the wordlines are described and depicted as containing a W/WN conductor and a SiN cap the present invention is not limited to just those types of wordlines. Instead, all types of wordlines that are well known to those skilled in the art are contemplated herein. The wordline stack is formed utilizing conventional deposition processes including, but not limited to: CVD, plasma-assisted CVD, chemical solution deposition, plating, sputtering or other like deposition processes. The patterning of the wordline stack is achieved utilizing conventional lithography and etching. Spacers 58 which are composed of the same or different dielectric material as the wordline capping layer are then formed by conventional deposition and etching processes. It is noted that the above steps form the structure shown in FIG. 4 in which spacers 58 are present on the wordlines as well as the stack of polysilicon and dielectric capping layers present in the support region. Note that at the time of patterning the array wordlines, the stack thickness in both the array and supports are approximately coplanar. [0083] Block mask 60 is then applied to the support regions to allow the removal of the TTO oxide layer over the bitline diffusion regions. Specifically, the block mask is formed utilizing conventional deposition processes and lithography. The TTO ( 24 ) in the array region is then removed utilizing an etching process which has a high-selectivity for removing oxide so as to provide the structure shown in FIG. 5. It is possible to eliminate block mask 60 if SiN is employed on top of the capping dielectric layer 44 ; in that case, TTO 24 may be removed maskless to SiN caps of the wordlines and supports. [0084] Block mask 60 is then stripped from the support region, and an N+ doped polysilicon layer 62 , which will subsequently become the bitline of the structure, is deposited by conventional deposition processes well known to those skilled in the art. For example, a conventional in-situ doping deposition process or deposition followed by ion implantation may be used in forming N+ polysilicon layer 62 along with an optional SiN cap. Using a block mask, not shown, the N+ doped polysilicon layer is removed by a conventional etching process from the support areas selective to the dielectric cap layer providing the structure shown in FIG. 6 [0085] After stripping the block mask used in forming the structure shown in FIG. 6, the exposed dielectric cap in the support region is optionally removed selective to polysilicon. A doped glass layer 64 such as boron doped silicate glass is next deposited by conventional means so as to form the planar structure shown in FIG. 7. The SiN cap in the array prevents auto-doping of the N+ polysilicon by the BSG layer. Note that BSG may be replaced by phosphorus silicate glass (PSG) or arsenic doped silicate glass (ASG). [0086] The doped glass layer and underlying TEOS layer in the supports is now patterned selective to silicon by a conventional reactive-ion etching (RIE) process so as to provide the structure shown in FIG. 8. It is noted that in an alternative embodiment of the present invention, the doped glass layer is replaced with a bilayer resist. [0087] Next, using the patterned doped glass layer and underlying TEOS in the supports as a hard mask, the underlying polysilicon regions, i.e., bitline polysilicon in the array and first polysilicon layer in the support region, are patterned selective to SiO 2 SO as to provide the structure shown in FIG. 9. Specifically, the bitline polysilicon is patterned into bitlines and the first polysilicon in the support region is patterned into a support gate region 48 . The doped glass material layer is then removed using an etching process that is substantially selective to the TTO, dielectric capping and oxide layers. During this step of the process, the gate conductor guard ring 65 is formed in the memory structure. [0088] A thin screen oxide layer 66 is then formed by conventional deposition or thermal growing processes on the exposed poly and single crystal silicon surfaces, See FIG. 10. LDD (lightly doped diffusion) or extension source/drain implants regions 68 are then formed in predetermined regions of the substrate by conventional lithography and ion implantation, See FIG. 10. These implants are typically carried out using a low-concentration of dopant dose on the order of 5×10 13 -5×10 14 cm 2 . [0089] Next, additional spacers 70 composed of an insulator material such as SiN are then formed in the array and support regions by utilizing a conventional deposition process and etching, an appropriate photoresist mask 72 is then formed in the structure so as to selectively block the array regions and areas of the support are subjected to ion implantation so as to form source/drain regions 74 , See FIG. 11 in the structure. It is noted that these implants set the workfunctions of the gate conductors in the support regions, and that prior to forming the source/drain regions, the screen oxide is removed from the structure utilizing a chemical etchant such as HF. [0090] [0090]FIG. 11 includes a structure in which the exposed silicon surfaces thereof are subjected to a conventional salicidation process which is capable of forming salicided regions 76 in the structure. Specifically, salicide regions are formed on the bitline region, the support gate region and the source/drain region. Following the salicidation process, an interlevel dielectric material 78 such as a CVD oxide is deposited on the structure and then patterned and etched in the manner shown so as to form via openings 80 in the interlevel dielectric material. Conventional processes which are well known to those skilled in the art follow the formation of the vias in the structure. [0091] The second embodiment of the present invention will now be described in more detail by referring to FIGS. 13-20. In the second embodiment of the present invention, a simplified process is employed which results in an array/support transition region which does not contain a gate conductor ring over the isolation region around the perimeter of the array. In this embodiment, the block mask used to protect areas outside the array during the removal of the TTO layer in the first embodiment (FIG. 5) is eliminated. Furthermore, the dielectric capping layer protecting the supports polysilicon is removed early in the process. This change results in improved planarity, eliminating the need for employing the planarizing doped glass material layer shown in FIG. 7. Thus, the support gate stack height which needs to be patterned is slightly reduced, resulting in improved linewith control. [0092] The initial structure employed in this embodiment of the present invention is similar to that shown in FIG. 1 except that the isolation region extends into a portion of one of the DRAM cells in the array region, See FIG. 13. Nitride layer 40 , support gate oxide 46 , first polysilicon layer 42 and dielectric capping layer 44 are formed as described above providing the structure shown in FIG. 13. [0093] As described above, standard mask 50 formed by lithography and etching is used to remove the dielectric capping layer and the first polysilicon layer from the array so as to provide the structure shown in FIG. 14. Exposed portions of the nitride layer in the array region are thereafter removed selective to oxide and silicon. [0094] After removal of the exposed nitride layer, a wordline gate stack consisting of W/WN 54 capped with SiN 56 is deposited and patterned to form wordlines 52 , see FIG. 15. This figure also shows the presence of insulating spacers 58 which are formed in the conventional manner described hereinabove. [0095] [0095]FIG. 16 shows the structure after an anisotropic etching process is used to remove the exposed TTO in the array region and the dielectric capping layer from the first polysilicon layer in the support region. This etching step also results in etching into the top of the exposed portion of isolation region 16 . [0096] [0096]FIG. 17 shows the structure after a conformal layer of undoped polysilicon 61 is deposited on the structure. The undoped polysilicon layer is deposited utilizing conventional means well known to those skilled in the art such as CVD, plasma-assisted CVD, chemical solution deposition and other like deposition processes. [0097] The undoped polysilicon layer provided in FIG. 17 is then patterned so as to simultaneously form the support gate region 48 and the bitline in the array region, See FIG. 18. A thin screen oxide 66 is then grown utilizing a conventional growing process such as thermal oxidation well known to those skilled in the art. The thin screen oxide layer of the present invention typically has a thickness of from about 1 to about 10 nm. LLD regions are formed about the gate region in the support region using lithography and implantation. [0098] Additional SiN spacers 70 are then formed, appropriate resist block mask 72 is applied to sequentially block the array and areas of the supports, and source/drain regions 74 are thereafter formed by ion implantation or thermal diffusion. These implants, which are shown in FIG. 19, set the workfunction of the gate conductors in the supports and also dopes bitline polysilicon 61 in the supports so as to form doped polysilicon region 63 therein. [0099] [0099]FIG. 20 shows the structure which is obtained after the following processing steps are performed: Following the source/drain, dual workfunction and bitline implants and removal of the screen oxide, the exposed silicon surfaces are salicided utilizing conventional salicidation processing steps well known to those skilled in the art so as to form salicide regions 76 in the structure. Interlevel dielectric 78 is thereafter deposited and patterned so as to form via openings 80 therein. [0100] The third embodiment of the present invention which forms a local interconnect wiring level which is consistent with the process steps described in the previous two embodiments will now be described in detail with reference to FIGS. 21-27. [0101] First, the structure shown in FIG. 21 is provided utilizing the processing steps mentioned hereinabove. A standard mask (formed by standard lithography and etching), not shown, is used to remove the dielectric capping layer and first polysilicon layer from the array and thereafter the nitride in the array region is removed so as to provide the structure shown in FIG. 22. [0102] A local interconnect mask 82 is then formed on the structure utilizing conventional lithography and etching which are both well known to those skilled in the art and is used to selectively open oxide layer 46 which receive subsequent implants for the interconnect contact areas, See FIG. 23. [0103] Following the interconnect implant which is carried out utilizing conventional ion implantation processes well known to those skilled in the art, the expose gate oxide 46 is removed, See FIG. 24. The local photoresist is removed and the process steps described above in forming the wordline conductors and spacers is employed forming the structure shown in FIG. 24. The interconnect diffusion is labeled as 92 and local interconnect is labeled as 94 . Note the local interconnect is comprised of the same material as the wordlines. [0104] Processing steps as described in the first embodiment continues with the deposition of the polysilicon bitline contact layer, opening of this layer and deposition of the planarizing doped glass material so as to provide the structure shown in FIG. 25. [0105] [0105]FIG. 26 shows the structure after bitline and support gates are patterned and FIG. 27 shows the structure after salicidation. The local interconnects may be used to electrically connect regions of substrate over isolation oxide 16 using wordline conductor 54 . [0106] It is noted that the various embodiments of the present invention which are described above and which are depicted in greater detail in FIGS. 1-27 provide the following advantages over the existing art: [0107] 1. Dual workfunction process saves two deep—UV masks relative to conventional processing; [0108] 1a. Common shared gate conductor/array 3 F pitch bitline masking step for improved lithography using 248 nm, and [0109] 1b. Shared bitline conductor/contact process. [0110] 2. Decoupled array and support processing (independent support gate conductor and wordline lithography). [0111] 3. Provides salicided gates and source/drain support MOSFETs in a vertical MOSFET EDRAM process. [0112] 4. Salicided bitline conductor. [0113] 5. Provides local interconnects with the addition of a masking step. [0114] While this invention has been particularly shown and described with respect to preferred embodiments thereof, it will be understood be those skilled in the art that the foregoing and other changes in forms and details may be made without departing from the scope and spirit of the present invention. It is therefore intended that the present invention not be limited to the exact forms and details described and illustrated but fall within the scope and spirit of the appended claims.

Methods of preparing dual workfunction high-performance support metal oxide semiconductor field effect transistor (MOSFETs)/embedded dynamic random access (EDRAM) arrays are provided. The methods describe herein reduce the number of deep-UV masks used in forming the memory structure, decouple the support and arraying processing steps, provide salicided gates, source/drain regions and bitlines, and provide, in some instances, local interconnects at no additional processing costs. Dual workfunction high-performance support MOSFETs/EDRAM, arrays having a gate conductor guard ring and/or local interconnections are also provided.

CROSS-REFERENCE TO RELATED APPLICATIONS This application is related to commonly-assigned applications Ser. No. 09/586,044, titled “Low Flow Fluid Film Seal for Hydrogen Cooled Generators”; Ser. No. 09/586,045, titled “Diffusion and Mass Transfer Prevention Seal for Hydrogen Cooled Generators” and Ser. No. 09/657,527, titled “Heat-Resistant Magnetic Silicone Rubber Brush Seals in Turbomachinery and Methods of Application,” the subject matters of which are incorporated herein by reference. BACKGROUND OF THE INVENTION The present invention relates to generators, e.g., hydrogen cooled generators, and particularly relates to a flexible magnetic brush seal useful in various sealing environments in the generator. Particularly, the present invention relates to a hydrogen cooled generator employing a flexible magnetic rubber brush seal, e.g., as a low flow fluid film seal and/or as a diffusion and mass transfer prevention seal. In turbomachinery such as gas and steam turbines, compressors and turbopumps, a number of seals are used at different locations for minimizing leakage flows. For example, seals may be provided between sealing surfaces which are both movable relative to one another or between components in which one component moves relative to another component, e.g., a housing wall and a rotating shaft. Brush seals, particularly in turbomachinery, typically comprise a plurality of elongated wire bristles in contact with a movable, for example, rotating surface. The bristles provide a tight, rub-tolerant seal which experience only slight degradation over time. The bristles of the seal are compliant in use and thus minimize damage due to transient impact between the components being sealed. A typical brush seal is formed by folding bristles over a rod with an outer clamp maintaining the folded bristles, squeezing the bristles between a folded metal plate forming a clamp or sandwiching the bristles between a pair of supporting metal plates and welding the plates and bristles at their proximal ends to one another. The distal ends of the bristles typically project a certain distance from the margins of the backing plates or clamps to engage the opposing sealing component, for example, a rotor. Common to these types of brush seals is that the bristle holder or carrier is formed of metal which is usually machined with a tight tolerance and thus the brush seal is applicable only to specific sealing dimensions. For other sealing dimensions, for example, diameters, a separately manufactured and distinct brush seal must be used in order to dimensionally fit the seal with its carrier. Consequently, the brush seals are costly in terms of tooling, manufacturing and installation and long cycle times in brush seal manufacturing and retrofitting are required. In generators, for example, hydrogen cooled generators, an end wall or casing surrounds a rotor and seals are interposed between the housing wall and the rotor to seal between a hydrogen atmosphere on one side of the wall and oil on the opposite side of the housing wall in a bearing cavity. Low flow fluid film seals are conventionally used on hydrogen cooled generators as dynamic rotor seals with near zero leakage. Turbine oil is the traditional working fluid of these seals because the turbine/generator unit must be supplied with turbine oil for its bearings. Low flow fluid film seals are generally directed along the rotor by a pair of low clearance rings about the rotor shaft. In a typical system, the oil flows past one seal ring into the bearing cavity and past the other seal ring and an additional oil deflection seal into the hydrogen environment within the housing wall. Oil entering the hydrogen side entrains hydrogen gas, which is then removed from the generator and vented from the system. Hydrogen consumption therefore represents a continuous and substantial expense to the user of the hydrogen cooled generator. The low flow fluid film seals and the oil deflection seals are typically about different diameters of the rotor. BRIEF SUMMARY OF THE INVENTION In accordance with a preferred embodiment of the present invention, there is provided a brush seal for use in a generator at various and different sealing locations. For example, in a hydrogen cooled generator, the brush seal hereof may be used as a low flow film seal and/or as a diffusion and mass transfer prevention seal. The seal of the present invention comprises a brush seal having a seal body formed of a flexible magnetic material such as magnetic silicone rubber material. Preferably, the bristles are embedded, glued or otherwise secured to the brush seal body such that the bristles project from the body, terminating in tips for sealing engagement with the opposing sealing component such as the generator rotor. The bristles are preferably formed of Kevlar® or polyester material. It will be appreciated that by bending the magnetic silicone rubber of the brush seal body, the brush seal can fit a wide range of sealing dimensions, e.g., diameters, in complex sealing geometry. For example, where the brush seal is to be applied between a fixed annular structure and a shaft rotating within the annulus, the brush seal may be flexed to conform to the dimensions of the two components. It will be appreciated that the brush seal body, together with the bristles carried thereby, can be flexed or bent into virtually any shape, e.g., an irregular or circular shape having different dimensions and thus may be used as a brush seal for differently dimensioned components, such as low flow fluid seals and/or diffusion and mass transfer prevention seals used in hydrogen cooled generators. Additionally, by forming the brush seal body from a magnetic material, the seal can be readily adhered to one of the sealing components. Preferably, the adherence is temporary until the seal body can be adjusted and secured in final position. Ancillary jigs or fixtures useful to maintain the brush seal body in position while adjustments are being made prior to final securement are entirely eliminated. The magnetic rubber is preferably formed of a composite material of ferrite magnetic powder and a silicone polymer. With these characteristics, the brush seal body can be bent, twisted or coiled and thus easily configured for installation. In accordance with a preferred embodiment of the present invention, the flexible magnetic brush seal can be used as a low flow fluid film seal in the hydrogen cooled generator which reduces the film flow of oil into the hydrogen atmosphere, thereby reducing hydrogen consumption, with the added benefits of facilitating manufacture and assembly of the brush seal. To accomplish this, the flexible magnetic low flow film seal is provided between the rotor and the housing wall, segregating the hydrogen atmosphere on one side of the wall and the oil and air mix of the bearing cavity on the opposite side of the wall. The flexible magnetic brush seals may be provided in pairs with a coil spring engaging between the pairs of brush seal bodies, biasing the bodies for axial separation and radial inward movement toward the rotor to maintain the bristles in contact with the rotor. In this sealing environment, oil or another fluid for forming the fluid film is pumped into the sealing space at a higher pressure than the seal casing. The oil or fluid is constricted by the brush seal to create a low flow film seal. By reducing the flow of the fluid to a minimum required to maintain a complete circumferential film, hydrogen consumption is reduced. The flexible magnetic brush seal may also be employed as a diffusion and mass transfer prevention seal in a hydrogen cooled generator. Thus, the brush seal hereof may be interposed as an oil deflector seal between the hydrogen atmosphere on one side of a generator housing wall and a seal cavity on an opposite side of the oil deflector seal. The seal cavity is an intermediate cavity containing lower purity hydrogen than the hydrogen-filled generator casing and generally lies inboard of the low flow fluid film seal. Typically, this seal is employed at an axial location of the rotor having a different diameter than the rotor diameter at the location of the low flow fluid film seal. Thus, a larger diameter flexible magnetic brush seal hereof is provided across the seal casing and rotor between the hydrogen cooled generator cavity and the seal cavity. This seal cavity greatly reduces the flow of hydrogen from the generator cavity across the seal into the hydrogen seal cavity and flow of oil along the shaft into the generator housing. As a consequence, a significantly greater difference between the purity of hydrogen of the two cavities on opposite sides of the seal casing is provided, affording reduced diffusion and mass transfer of the hydrogen across the seal. The brush seal in this sealing environment is also bi-directional, i.e., not only preventing diffusion and mass transfer of hydrogen into the seal cavity but also serving to prevent oil or oil mist from the seal cavity from entering the generator cavity. Significantly, while the diameters of the two brush seals described for use in the hydrogen cooled generator are different, the same stock brush seal can be used for both seals. That is, a linear brush seal can be fabricated and, when cut to appropriate length, used as either seal. The brush seal is therefore not limited to a fixed diameter but is useful for a large number of different seal diameters. In a preferred embodiment according to the present invention, there is provided in a hydrogen cooled generator having a rotor, a component part and a seal sealing between the rotor and the component part for segregating an at least in part hydrogen atmosphere on one side of the seal and a cavity on an opposite side thereof, the seal including a brush seal extending between the component part and the rotor, the brush seal including a brush seal body and a plurality of bristles projecting from the body with tips thereof engaging the rotor, the brush seal body being formed of a flexible material. In a further preferred embodiment according to the present invention, there is provided in a hydrogen cooled generator having a rotor and a seal sealing between the rotor and a housing wall for segregating a hydrogen atmosphere on one side of the seal and a seal cavity on an opposite side thereof containing a gas of lesser purity than the hydrogen atmosphere, the seal including a brush seal extending between the component part and the rotor, the brush seal including a brush seal body and a plurality of bristles projecting from the body with tips thereof engaging the rotor and preventing diffusion and mass transfer of the hydrogen atmosphere on one side of the wall into the seal cavity, the brush seal body being formed of a flexible magnetic material. In a still further preferred embodiment according to the present invention, there is provided in a hydrogen cooled generator having a rotor and a seal sealing between the rotor and a housing wall with at least in part a hydrogen atmosphere on one side of the seal and a bearing cavity containing a fluid on an opposite side thereof, the seal including a low flow fluid film brush seal extending between the wall and the rotor, the brush seal including a brush seal body and a plurality of bristles projecting from the body with tips thereof engaging the rotor for substantially segregating the hydrogen atmosphere and the fluid in the bearing cavity, the brush seal body being formed of a flexible magnetic material. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary cross-sectional view of a pair of seals between a housing component and a rotor of a hydrogen cooled generator, constructed in accordance with a preferred embodiment of the present invention; FIG. 2 is an enlarged fragmentary cross-sectional view of a low flow film seal corresponding to one of the seals illustrated in FIG. 1; FIG. 3 is a perspective view of a pair of semi-circular seal rings for use in holding the brush seal; and FIG. 4 is a fragmentary perspective view of the brush seal hereof. DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings, particularly to FIG. 1, an end portion of a hydrogen cooled generator having a rotor 10 , a housing wall or casing 12 , and a portion of an end shield 14 is illustrated. Also illustrated is a rotor shaft bearing 16 comprised of inner and outer bearing rings 18 and 20 , respectively, disposed in a bearing cavity 22 containing oil and a bearing cap 24 which, together with an end oil deflector 26 , closes off outside portions of the oil-bearing cavity 22 about rotor 10 . Along the inside surface of the housing wall 12 (to the left of wall 12 in FIG. 1 ), there is a hydrogen atmosphere designated 28 within the generator for cooling the generator. A low flow fluid film seal, generally designated 29 , is provided between the rotor 10 and the housing wall or casing 12 . The wall or casing 12 constitutes a component part of the hydrogen generator to maintain the hydrogen atmosphere 28 segregated from the fluid in oil-bearing cavity 22 . A seal casing 30 is interposed between the housing wall 12 and rotor 10 . The seal casing 30 comprises an annular plate or ring secured to insulation 32 along its radially outer diameter by bolts passing through insulation 32 . As illustrated, the seal casing 30 includes an annular chamber 34 opening radially inwardly toward the rotor 10 and defined between a pair of axially spaced flanges 36 and 38 . Within the chamber 34 , there are provided a pair of low clearance seal rings 40 and 42 . Also in chamber 34 is an annular garter spring 44 which engages against inclined surfaces 43 and 45 (FIG. 2) along radial outermost portions of the seal rings 40 and 42 , respectively. The spring 44 biases the seal rings 40 and 42 axially and radially. It will be appreciated that the spring 44 may be formed in two generally semi-circular configurations attached to pins at opposite ends, the pins being secured to the seal casing 30 . It will be appreciated that the cavity 34 is provide with oil under pressure to provide a thin film of oil along the surface of rotor 10 . Brush seals housed within the seal rings 40 and 42 are described below. One or more brush seals 74 described below may also be provided as part of a diffusion and mass transfer prevention oil deflector seal, generally designated 50 . Seal 50 is disposed between the housing wall 12 and rotor 10 inboard of the seal casing 30 defining a seal cavity 52 therebetween. As a result, the seal cavity contains a significantly lesser purity of hydrogen than the hydrogen atmosphere in the generator cavity 28 . The diffusion and mass transfer prevention seal 50 increases the resistance to diffusion and resistance to mass transfer of hydrogen across the seal 50 into the seal cavity 52 such that hydrogen consumption is substantially reduced. Note that the sealing diameter of the seal 50 is greater than the sealing diameter of seal 29 . In accordance with the present invention, one or more flexible magnetic brush seals are used as part of the low flow fluid film seal 29 and/or the diffusion and mass transfer prevention seal 50 . The brush seal will be described in conjunction with the low flow fluid film seal and it will be appreciated that the brush seal as described is equally applicable to the diffusion and mass transfer prevention seal 50 , albeit the seal diameters are different. In the low flow fluid film seal illustrated in FIG. 2, rings 40 and 42 have grooves 70 and 72 , respectively. Identical brush seals are applied in each groove 70 and 72 and a description of one suffices for a description of the other. The brush seal 74 includes a brush seal body 76 and a plurality of bristles 78 forming a bristle pack 80 carried by the brush seal body 76 . In a preferred embodiment, the brush seal body 76 is comprised of a magnetic flexible silicone rubber material in the general shape of an elongated channel having a base 82 and opposite sides or legs 84 and 86 . The bristle pack 80 comprises the bristles 78 disposed in the groove or channel of the body 76 , terminating in bristle tips 88 engageable with rotor 10 . Typically, the bristles are elongated, formed of metal and have diameters ranging from 0.002 to 0.01 inch, depending upon the temperature, pressure and sealing pattern in which the bristles are to be used. It will also be appreciated that non-metal materials such as aramid fibers, e.g., Kevlar®, may be utilized and in hydrogen cooled generators are preferred. While a magnetic silicone rubber is preferred, it will be appreciated that other types of materials may be used to form the channel, particularly in the present application, in which high temperatures and pressures are not typically encountered. The silicone rubber is comprised of ferrite magnetic powder and silicone polymer. With these characteristics, the brush seal body and bristles can be bent, twisted, coiled and easily fabricated. It will be appreciated that the seal can be readily fabricated, for example, by planting packed bristles in extruded magnetic rubber. Alternatively, a bristle pack with proximal ends of the bristles secured, for example, by welding to one another or about a rod, may be co-extruded with the rubber, for example, in a dovetail-type configuration, to retain the bristle pack within the rubber channel. Alternatively, the bristle pack with a dovetail-shaped proximal end may be inserted into a correspondingly-shaped slot in a circumferential direction into the rubber When used as a low flow fluid film seal 29 as illustrated in FIG. 2 and in the hydrogen cooled generator of FIG. 1, the seal rings 40 and 42 each containing the brush seal are arranged as mirror images of one another. The coil spring 44 maintains an axial gap between the seal rings 40 and 42 , as well as maintains the tips of the bristles in contact with the rotor. The disclosed arrangement permits the seal rings 40 and 42 to be displaced in a radial direction. Also as illustrated in FIG. 2, a brush clamp 90 is illustrated. The brush clamp 90 comprises a metal plate having an opening for receiving a fastener 92 . Clamp 90 has a tapered end 94 for overlying a correspondingly tapered portion along the lower edge of the channel. Clamp 90 thus overlies the exposed annular side of the rubber brush seal and portions of the metal ring and is finally secured by fastener 92 to retain the brush seal in the groove. Also as noted in FIG. 2, the sides of the channel are recessed adjacent the distal end of the channel and away from the bristles. This permits the bristle tips to flex in either axial direction in the event of pressure changes on either side of the seal. A significant advantage of the brush seal of the present invention is that it may be formed in a linearly extending strip, for example, as illustrated in FIG. 4 . For example, the rubber material may be extruded in the form of a channel with the bristles planted in the base of the channel-shaped extrusion and extending at a cant angle relative to the longitudinal dimension of the strip of about 40 to 50°. It will be appreciated that the linear extending strip can be bent or flexed to a variety of dimensions. Once the long dimension of the brush seal strip is determined for a particular sealing application, the strip can be cut to the appropriate length and flexed for reception in the seat of the seal, e.g., the groove 70 of the low flow fluid film seal or in the groove of a retainer ring 94 for the seal 50 . Also, the magnetic material of the brush seal provides a magnetic attraction with the metal holder therefor. Consequently, the brush seal can be disposed in the holder and temporarily held by magnetic attraction, while the clamps are applied to finally secure the brush seal to its carrier. While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

A flexible magnetic brush seal is employed as a low flow fluid film seal and/or a diffusion and mass transfer prevention seal in a hydrogen generator to seal between a hydrogen atmosphere and a fluid on an opposite side of the seal. The brush seal is formed of a magnetic rubber flexible material, enabling the seal to be flexed and altered in dimension to fit a number of different sealing environments of different dimensions. The magnetic properties of the brush seal enable temporary securement of the brush seal to a brush seal holder prior to final securement.

This is a continuation-in-part of application Ser. No. 10/408,311, filed Apr. 8, 2003 now U.S. Pat. No. 6,752,704, the entirety of which is incorporated herein by reference. BACKGROUND OF THE INVENTION The present invention is related to a grinder, and more particularly to a grinder in which the rotary shaft can be fixed without using any tool for replacing the grinding disc. A conventional pneumatic or electric grinder has a grinding disc mounted at bottom end for grinding or buffering a work piece. When grinding different work pieces, it is necessary to frequently replace the grinding disc. In the conventional grinding structure, an eccentric rotary shaft is disposed at bottom end of the rotor (pneumatic grinder) or the motor (electric grinder). A hexagonal nut is fixed at bottom end of the rotary shaft. A worm is disposed at the center of the top face of the grinding disc. The worm is screwed in the nut, whereby the grinding disc is drivable by the rotary shaft. In addition, a protective sheath is disposed at bottom end of the grinder for covering the grinding disc and providing a protective effect. The conventional grinder is equipped with a flat wrench. When replacing the grinding disc, the wrench is extended through the gap between the protective sheath and the grinding disc to fit onto the nut and prevent the rotary shaft from rotating. Under such circumstance, the grinding disc can be untightened or tightened. Such procedure is quite inconvenient, for the protective sheath obstructs the operator from seeing the nut. Therefore, it is hard for the operator to fit the wrench onto the nut. Moreover, the rotary shaft is eccentrically arranged and has unfixed position so that the operator often needs to try many times for wrenching the nut. Furthermore, in case there is no tool available, it will be impossible to replace the grinding disc. SUMMARY OF THE INVENTION It is therefore a primary object of the present invention to provide a grinder in which a structure is provided for fixing the rotary shaft, whereby the grinding disc can be replaced without using any tool. The present invention can be best understood through the following description and accompanying drawings wherein: BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective assembled view of a preferred embodiment of the present invention; FIG. 2 is a perspective exploded view according to FIG. 1 ; FIG. 3 is a longitudinal sectional view according to FIG. 1 ; FIG. 4 is a bottom view according to FIG. 1 ; FIG. 5 is a partially sectional view according to FIG. 1 ; FIG. 6 is a perspective assembled view of the support tray,. bracket and detent members of the present invention; FIG. 7 is a top view according to FIG. 6 , showing that the detent members are opened; FIG. 8 shows that the rotary disc of the present invention is turned to another position; FIG. 9 is a top view according to FIG. 8 , showing that the detent members are closed; and FIG. 10 is a bottom view of the present invention in the state of FIG. 9 . FIG. 11 is a perspective exploded view,of a part of another embodiment of the present invention; FIG. 12 is a perspective exploded view of still another embodiment of the present invention; FIG. 13 is a perspective assembled view of the embodiment of FIG. 12 , showing that the detent members are opened; FIG. 14 is a top view according to FIG. 13 ; FIG. 15 is a bottom view of the embodiment; FIG. 16 is a view according to FIG. 14 , showing that the detent members are closed; FIG. 17 is a bottom view according to FIG. 16 ; and FIG. 18 is a bottom view of still another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Please refer to FIGS. 1 and 2 . According to a preferred embodiment, the grinder 10 of the present invention includes a main body 20 , a rotary shaft 40 , a rotary disc 50 , a bracket 60 , a support tray 70 and detent members 80 . The main body 20 has a barrel section 22 . At least the bottom end of the barrel section is circular. The main body also has a circular loop section 24 having a diameter larger than that of the barrel section 22 and positioned at bottom end of the barrel section. The inner circumference of the loop section has three connecting sections 26 arranged at equal intervals and connected between the barrel section 22 and the loop section 24 . The three connecting sections define three hollow sections 28 at equal intervals. In addition, two figure marks 30 , 32 are disposed on top face of one of the connecting sections. Referring to FIG. 3 , a space 34 is formed in the barrel section 22 in which a driving unit 35 is accommodated. In this embodiment, the grinder is a pneumatic grinder, the driving unit 35 is a pneumatic cylinder 36 in which a rotor 37 is disposed. The rotary shaft 40 is eccentrically pivotally connected with bottom end of the driving unit 35 and is driven by the driving shaft 38 of the driving unit. The rotary shaft is eccentrically arranged so as to provide a vibration effect. The bottom end of the rotary shaft 40 is formed with an axial thread hole 42 . In addition, an annular toothed section 45 is formed along the circumference of the bottom end of the rotary shaft as shown in FIG. 4 . The rotary disc 50 , referring to FIGS. 1 and 2 , in this embodiment, is composed of three arched bodies 52 having equal arch length (120 degrees). The three arched bodies 52 are annularly arranged around the loop section 24 to shield the top face of the connecting sections 26 . The bracket 60 has a disc-like body section 62 and three legs 64 arranged on the circumference of the body section at equal intervals. In addition, the body section 62 is formed with a central through hole 65 and three oblique guide slots 66 at equal intervals. Each guide slot has an inner end 661 and an outer end 662 . In radial direction, the inner end 661 is closer to the center of the body section 62 , while the outer end 662 is farther from the center of the body section. The bracket 60 is mounted in the loop section 24 with the three legs 64 respectively extending through the three hollow'sections 28 . Each leg is fixed at a pivot hole 521 of the arched body 52 by a screw. 69 as shown in FIG. 5 . The three arched bodies 52 are respectively fixed with the three legs so that the arched bodies keep having a circular configuration without departing from each other. When rotating the rotary disc 50 on the loop section 24 , the bracket 60 is driven and moved. The legs 64 and the guide slots 66 are concentric with the body section 62 and the body section is concentric with the driving shaft 38 of the driving unit 35 . The support tray 70 is formed with a central circular hole 72 . Three rail channels 74 are-radially formed on the top face of the support tray 70 at equal angular intervals. Three plate-like detent members 80 respectively disposed in the three rail channels 74 and slidable along the rail channels. An inner end of each detent member 80 is formed with an arched toothed section 82 having several teeth. The three arched toothed sections 82 form a circular configuration. The pitch between the teeth of the toothed section 82 is equal to the pitch between the teeth of the annular toothed section 45 of the rotary shaft 40 . Three guide posts 84 are respectively fixed with the three detent members 80 . After the detent members 80 are mounted into the support tray 70 , the support tray is fixedly connected with small projections 241 formed on inner circumference of the loop section 24 by three screws 86 as shown in FIGS. 2 and 3 . Accordingly, the support tray is fixed in the loop section. The support tray and the detent members right attach to the bottom face of the body section 62 of the bracket 60 . Referring to FIG. 6 , the three guide posts 84 are fitted in the guide slots 66 . The support tray 60 is concentric with the bracket 70 . After the components 60 , 70 , 80 are mounted in the loop section 24 , as shown in FIG. 3 , the annular toothed section 45 of the bottom end of the rotary shaft 40 extends into the bracket and the circular hole 72 of the support tray. A hollow protective sheath 90 made of hard plastic or rubber material is fitted around the loop section 24 to provide a protective effect. FIG. 1 is a perspective assembled view of the present invention, in which the rotary disc 50 has at least one window 55 (which is inward recessed in this embodiment). The window 55 corresponds to the connecting section 26 having the two marks 30 , 32 . In FIG. 1 , the window 55 is right positioned at the mark 30 which is a figure of a wrench. Under such circumstance, the rotary disc 50 is positioned in an opened position. In this position, as shown in FIG. 7 , the guide posts 84 are positioned at outer ends 662 of the guide slots 66 and the three detent members 80 are expanded outward. In this state, referring to FIG. 4 , the rotary shaft 40 is not restricted and can freely rotate. After activating the grinder, the rotary shaft can drive the grinding disc (not shown) to grind a work piece. When replacing the grinding disc, the operator clockwise turns the rotary disc 50 to a closed position as shown in FIG. 8 , in which the other mark 32 is exposed through the window 55 . The mark 32 is a figure showing that a wrench is fitted onto a nut to indicate the operator of the restriction of the rotary shaft. Referring to FIG. 8 , when the rotary disc 50 is clockwise angularly displaced, the bracket 60 is synchronously rotated. At this time, the angular positions of the three guide slots 66 are changed and the guide posts 84 are moved from the outer ends 662 of the guide slots to the inner ends 661 thereof as shown in FIG. 9 . When the guide posts 84 are displaced, the detent members 80 are driven by the guide posts to inward slide along the rail channels 74 to a closed position, the three detent members contract and the arched toothed sections 82 thereof are closed into a complete circle. Under such circumstance, referring to FIG. 10 , the arched toothed sections 82 of the detent members are engaged with the annular toothed section 45 of the rotary shaft 40 to fix and prevent the rotary shaft from rotating. An operator can screw the worm of the grinding disc into the thread hole 42 of the rotary shaft or unscrew the worm out of the thread hole so as to replace the grinding disc. It should be noted that when the three detent members 80 are closed, the three arched toothed sections 82 form a circle having a circumferential length equal to the circumferential length of the circle defined by the eccentric rotation of the rotary shaft 40 . Therefore, after the grinder stops operating, no matter in what angular position the rotary shaft stops, the rotary shaft is clamped and fixed by the detent members. When activating the grinder, the rotary disc 50 is counterclockwise turned back to the opened position as shown in FIG. 1 to move the guide posts 84 to the outer ends of the guide slots. At this time, the detent members are restored to the expanded state as shown in FIG. 7 and disengaged from the rotary shaft. In addition, three locating sections 76 can be disposed on the support tray at equal intervals as shown in FIG. 9 . Three dents 68 are disposed on the body section 62 of the bracket at equal intervals. Two sides of the dent 68 abut against the locating section 76 to serve as the dead end of the movement of the rotary disc and the bracket. By means of simple operation, the rotary shaft can be fixed or released for replacing the grinding disc without using any tool. This is convenient and facilitates the operation. The marks 30 , 32 enable an operator to judge whether the rotary shaft is freely rotatable or fixed. FIG. 11 shows the bracket 92 and detent members 95 of another embodiment of the grinder of the present invention. In this embodiment, three guide slots 96 are respectively formed on the three detent members 95 , while the three guide posts 94 are disposed on the bracket 92 and inserted in the guide slots 96 . Accordingly, when rotating the bracket 92 , the detent members 95 are driven to displace along the rail channels. FIG. 12 shows still another embodiment of the grinder 100 of the present invention, in which the main body 110 , rotary disc 112 , bracket 114 , support tray 116 and detent members 120 are identical to those of the first embodiment. This embodiment is mainly different from the first embodiment in that an inner end of one detent member 120 a of the three detent members is formed with an arched toothed section 125 , while the inner ends 126 of the other two detent members 120 b , 120 c are free from any toothed section. The inner ends 126 can be plane faces, arched faces or inward recessed as shown in FIG. 12 . Similarly, referring to FIGS. 14 and 15 , when the three detent members 120 are positioned in the expanded position, the rotary shaft 118 is not restricted so that the grinding disc is driven to freely rotate. When replacing the grinding disc, the bracket 114 is turned to the closed position as shown in FIG. 16 At this time, the three detent members 120 are driven to inward move along the rail channels 117 to the closed position as shown in FIG. 17 . Under such circumstance, the toothed section 125 of the detent member 120 a engages with the toothed section 119 of the rotary shaft 118 so that the rotary shaft cannot rotate. At this time, the grinding disc can be replaced. When the three detent members are closed, in the case that the position of the rotary shaft 118 is not adjacent to the detent member 120 a , but one of the other two detent members 120 b or 120 c , for example, adjacent to the detent member 120 b as shown by phantom line of FIG. 16 , during closing procedure of the detent member 120 b , the inner end 126 of the detent member 120 b will push the rotary shaft to move. At this time, the center c of the rotary shaft will angularly displace along the arched line d to the position as shown by solid line of FIG. 16 . Under such circumstance, the rotary shaft is engaged with the toothed section 125 of the detent member 120 a . In other words, when the detent members are closed, no matter where the rotary shaft is positioned the rotary shaft will be engaged with the detent member 120 a and fixed. Also, after the three detent members are closed, the inner ends 126 of the detent members 120 b , 120 c define a narrow space within which the rotary shaft is restricted. Therefore, the rotary shaft cannot be disengaged from the detent member 120 a. FIG. 18 is a bottom view of still another embodiment of the present invention, in which the inner ends of two detent members 130 a of the three detent members 130 are formed with arched toothed sections 135 , while the inner end of the other detent member 130 b is free from any arched toothed section. The inner end of the other detent member can be a plane face, arched face or inward recessed. Similarly, when the detent members are closed, the rotary shaft cannot be disengaged from the detent members 130 a. It should be noted that the bracket be directly exposed to outer side of the main body, whereby an operator can directly turn the bracket.

A grinder with easily installable/detachable grinding disc, including: a main body in which a driving unit is disposed for driving a rotary shaft, an annular toothed section being formed on the circumference of the rotary shaft; a bracket rotatably disposed under the bottom face of the main body; a support tray disposed under the bracket, several rail channels being radially formed on the support tray; and a predetermined number of detent members respectively slidably disposed in the rail channels. When turning the bracket, the detent members are driven to move along the rail channels. When the detent members are contracted, the arched toothed sections of the inner ends of the detent members engage with the annular toothed section of the rotary shaft, whereby the rotary shaft cannot rotate for replacing grinding disc. After replacing the grinding disc, the detent members are moved outward along the rail channels to disengage from the rotary shaft.

TECHNICAL FIELD [0001] The present invention relates generally to nonwoven fabrics and their method of production, and more particularly to a process for making stabilized, highly durable hydroentangled webs, comprising a blend of textile length fibers where a portion of same are thermally fusible, and where such fabrics are suitable for commercial dyeing operations, most particularly jet-dye processes. BACKGROUND OF THE INVENTION [0002] Nonwoven fabrics are used in a wide variety of applications where the engineered qualities of the fabric can be advantageously employed. These types of fabrics differ from traditional woven or knitted fabrics in that the fabrics are produced directly from a fibrous mat eliminating the traditional textile manufacturing processes of multi-step yarn preparation, and weaving or knitting. Entanglement of the fibers or filaments of the fabric acts to provide the fabric with a substantial level of integrity. However, the required level of fabric integrity when such fabrics are used in highly abrasive environments is not possible by entanglement alone, and thus it is known to apply binder compositions or the like to the entangled fabrics for further enhancing the integrity of the structure. [0003] U.S. Pat. No. 3,485,706, to Evans, hereby incorporated by reference, discloses processes for effecting the hydroentanglement of nonwoven fabrics. More recently, hydroentanglement techniques have been developed which impart images or patterns to the entangled fabric by effecting hydroentanglement on three-dimensional image transfer devices. Such three-dimensional image transfer devices are disclosed in U.S. Pat. No. 5,098,764, hereby incorporated by reference, with the use of such image transfer devices being desirable for providing fabrics with the desired physical properties as well as an aesthetically pleasing appearance. [0004] In general, hydroentangled fabrics formed on the above type of three-dimensional image transfer devices exhibit sufficient strength and other requisite physical properties as to be suitable for a number of textile applications. [0005] However, many desired applications have requirements for commercial dyeing and wash durability, which are generally beyond the design capability of such fabrics. Typically, home or commercial laundering or the rigors of commercial dye house processes have a deleterious effect on these hydroentangled or imaged fabrics. The clarity of the raised image is reduced or “washed out” and the fabric surface becomes abraded with fibers forming pills on the fabric surface. Physical strength characteristics can also be reduced. [0006] Heretofore, chemical binder systems have been developed that provide high abrasion resistance to nonwoven, woven or knitted fabrics. Other binder compositions can provide durability to laundering and commercial dyeing processes. However, it will be appreciated that application of chemical binders also increases the complexity of the fabric manufacturing process and adds cost to the fabric thus produced. The use of such compositions also requires specialized equipment to mix and apply the binder formulations as well as to dry and cure the binder compositions after application to the fabrics. [0007] The addition of binder compositions has an effect on the fabric properties. The use of such binders generally produces fabrics which are stiffer than like fabrics produced without the binder application. Such stiffness will be recognized as being undesirable for apparel fabrics, where softness, suppleness and drapeability are highly preferred. SUMMARY OF THE INVENTION [0008] The present invention is directed to a process for making nonwoven fabrics which exhibit the desired durability to commercial dye house processing, most particularly jet-dye processing, as well as acceptable softness and drapeability. This is achieved by the inclusion of fusible fibers, preferably in the form of bicomponent fibers, most preferably nylon or polyester bicomponent fibers, into the fibrous matrix of the substrate web. Such fibers, when the entangled and patterned web is subjected to temperatures above the melting point of the lower melting component of the bicomponent fibers, acts to provide enhanced mechanical stability to the fibrous matrix of the web. An imaged nonwoven fabric with this added degree of mechanical stabilization has been found to be durable to commercial dye house processing, in particular to the mechanically aggressive jet-dye processing, and able to retain the imparted image quality under harsh mechanical conditions. [0009] A process for making a jet-dye process-durable nonwoven fabric in accordance with the present invention comprises the steps of providing a fibrous matrix to form a precursor web comprised of a blend of textile length fibers where at least a portion of those fibers are bicomponent, thermoplastic fibers. The fibrous component of the precursor web can be in the form of a fibrous batt or matrix containing a single homogenous blend of fusible fibers or in a layered fibrous batt having either the same or different fusible fiber blend ratios in each fibrous batt sub-layer, with the matrices consolidated to form the precursor web. The precursor web is positioned on a three-dimensional image transfer device with hydroentangling of the precursor web on the image transfer device effected to form an entangled and imaged web, with the image transfer device imparting the fibrous matrix with a three-dimensional spatial arrangement. [0010] Subsequent to the hydroentanglement and imaging of the web, the temperature of the web is elevated, such as during drying of the web, so that the lower melting point component of the bicomponent fusible fibers is softened or melted and acts to thermally bond fibers in the web together. The three-dimensional spatial arrangement of the fibrous matrix is thus secured. This results in an enhanced mechanical stability such that the highly durable fabric of the present invention is capable of being commercially dyed, without deleterious effects on aesthetic or physical properties. The commercial dye processing produces, as the final product, a colored, highly durable, imaged nonwoven fabric. [0011] Other features and advantages of the present invention will become readily apparent from the following detailed description, the accompanying drawings and the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS [0012] The invention will be more easily understood by a detailed explanation of the invention including drawings. Accordingly, drawings which are particularly suited for explaining the invention are attached herewith; however, is should be understood that such drawings are for explanation purposes only and are not necessarily to scale. The drawings are briefly described as follows: [0013] [0013]FIG. 1 is a diagrammatic view of a hydroentangling apparatus for practicing the process of the present invention by which a durable, imaged nonwoven fabric is formed; [0014] [0014]FIG. 2 is an illustration of the features of a three-dimensional image transfer device which can be employed in the apparatus of FIG. 1 for practicing the present invention; [0015] [0015]FIG. 2 a is a view taken along lines A-A of FIG. 2; [0016] [0016]FIG. 2 b is an isometric view of the features illustrated in FIG. 2; [0017] [0017]FIG. 3 is an isometric illustration of the features of a three-dimensional image transfer device which can be employed in the apparatus of FIG. 1 for practicing the present invention; [0018] [0018]FIG. 3 a is a plan view of the features shown in FIG. 3; [0019] [0019]FIG. 4 is an illustration of the features of a three-dimensional image transfer device which can be employed in the apparatus of FIG. 1 for practicing the present invention; [0020] [0020]FIG. 5 is a view taken along lines A-A of FIG. 4; [0021] [0021]FIG. 6 is a view taken along lines B-B of FIG. 4; [0022] [0022]FIG. 7 is an isometric illustration of the features shown in FIG. 4; [0023] [0023]FIG. 8 is plan view of an imaged nonwoven fabric of the present invention after Brush Pill testing; [0024] [0024]FIG. 9 is plan view of an imaged nonwoven fabric of the present invention without activation of the fusible fiber component, after Brush Pill testing; [0025] [0025]FIG. 10 is plan view of an imaged nonwoven fabric of the present invention after Brush Pill testing; and [0026] [0026]FIG. 11 is plan view of an imaged nonwoven fabric of the present invention without activation of the fusible fiber component. after Brush Pill testing. DETAILED DESCRIPTION [0027] While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment, with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiment illustrated. [0028] With reference to FIG. 1, therein is illustrated a hydroentangling apparatus, generally designated 10 , which can be employed for practicing the process of the present invention for manufacture of a durable, jet-dyed imaged nonwoven fabric. The apparatus is configured generally in accordance with the teachings of U.S. Pat. No. 5,098,764, to Drelich et al., hereby incorporated by reference. The apparatus 10 includes an entangling belt 12 which comprises a hydroentangling device having a foraminous forming surface upon which hydroentangling of a precursor web P, for effecting consolidation and integration thereof, is effected for formation of the present nonwoven fabric. The precursor web P is then hydroentangled and imaged on a three-dimensional image transfer device (ITD) at drum 18 under the influence of high pressure liquid streams (water) from manifolds 22 . [0029] In accordance with the present invention, at least a portion of the fiber or filament web consists of thermally fusible fibers, also called binder fibers, most preferably bicomponent fibers, that are activated through drying or heat setting steps that follow the imaging step. This blend of fusible fibers with the other fibers of the web provides for the subsequent thermal bonding of the fibers in the matrix. The result is an enhancement of the mechanical stability of the preferred spatial arrangement of the entangled fibers which result from the hydroentangling and imaging steps. This enhanced stability provides an entangled web with high durability such that the fabrics thus produced are capable of withstanding commercial dye house processing without deleterious effects on physical and aesthetic properties. Further, these fabrics, either before or after dyeing, exhibit softness and drapeability that is superior to similarly entangled and imaged fabrics that are stabilized by the application of a chemical binder system. [0030] As will be appreciated, the thermoplastic fusible fiber has a melt temperature less than the melt temperature or the decomposition temperature of the base fiber. The fusible fiber is selected from the group consisting of polyamide homopolymers, polyamide co-polymers, polyamide derivatized polymers, and combinations thereof. Alternatively, the fusible fiber is selected from the group consisting of polyester homopolymers, polyester co-polymers, polyester derivatized polymers, and combinations thereof. The base fiber is selected from the group consisting of natural fibers, thermoplastic fibers, thermoset fibers, and combinations thereof. The thermoplastic fiber can be polyester, while the natural fiber can be rayon. [0031] Referring again to FIG. 1, subsequent to the hydroentanglement, the entangled and imaged web can be dewatered, as generally illustrated at 20 , with the temperature of the web then elevated by heated air, such as by use of an oven or dryer 22 . The temperature of the web can be elevated by heated surface contact, such as by use of steam cans. Elevation of the web temperature to the melting point of the fusible fibers or fusible component of the bicomponent fusible fibers acts to thermally bond the fibers of the matrix together and thus secure the preferred arrangement of the fibers in the entangled and imaged web. [0032] After the heat setting step, a soft, durable, entangled and imaged nonwoven fabric is provided, which is suitable for further textile finishing. The fabric may be dyed, printed or finished by other techniques and used in apparel, home furnishing, upholstery or any number of applications. Notably, wash durability, pill-resistance and drape characteristics of sample fabrics, described hereinafter, meet the requirements for “top of bed” applications, that is, applications for home use such as comforters, pillows, dust ruffles, and the like. [0033] For each of the tested samples, a precursor web was formed by carding the blend of fibers in the specified ratio. Each precursor web was subjected to high pressure water jets prior to imaging for consolidating and integrating the precursor web, with the pre-imaging entanglement being effected with four manifolds at 14, each with three strips of orifices. The orifices were uniformly 0.005 inches in diameter and 50 orifices per inch of strip length. The entangling manifolds were operated at 100, 300, 600 and 800 psi, sequentially. [0034] Imaging was accomplished at imaging drums 18 using a three dimensional image transfer device and a series of three manifolds 22 with 0.0047 inch diameter orifices spaced at 43 orifices per inch. Each of the three manifolds was operated at 2800 psi. The overall line speed was 60 feet per minute. [0035] The entangled and imaged web of each of the tested fabrics was dewatered and thereafter dried and heat set at a temperature satisfactory to melt the lower melting point component of the fusible fibers. For example, the temperature used to heat set nylon bicomponent fiber samples was in the range of about 216° C., and for polyester/copolyester fusible fiber samples was in the range of about 130° C. The heat setting step is accomplished at process speeds compatible with the entangling and patterning process such that the drying and heat setting step would be in a continuous process with the rest of the manufacturing steps. The heat setting step acts to enhance the mechanical stability of the preferred spatial arrangement of the entangled fibers in the web, thereby providing the high degree of durability required for the final commercial dyeing process. [0036] After heat setting, the resultant fabrics exhibit sufficient durability to withstand commercial dye house processing, such as exemplified by jet-dyeing, such as in a jet dyeing apparatus. A jet-dyeing apparatus can be configured in accordance with known arrangements, such as exemplified by U.S. Pat. No. 3,966,406, hereby incorporated by reference. In general, jet-dye processing consists of a high-temperature, piece-dyeing machine that circulates the dye liquor through a Venturi jet, thus imparting a driving force to move the fabric through the process. Speeds of 80 to 300 meters per minute are standard for this type of operation. The fabric is totally immersed in the dye bath which is contained in the closed dye vessel, such that the process is discontinuous from the rest of the manufacturing process described for the present invention. EXAMPLES Example 1 [0037] An imaged nonwoven fabric having a before dyeing-basis weight of three-ounces per square yard was prepared using a fiber blend of 90 percent weight of base fiber to 10 weight percent fusible fiber. Base fibers utilized were Wellman 472, 1.2 denier polyester staple fibers. The heat fusible fibers were obtained from Dupont de Nemours as Type 3100 nylon bicomponent fibers. Type 3100 is a sheath/core bicomponent fiber where the core is nylon 6,6 and the sheath is nylon 6. The material fabricated in this example utilized an entangling drum 12 in the form of “left hand twill” as depicted in FIG. 2. A heat setting temperature of 216° C. was suitable for fabrics containing this fusible fiber. In the course of preparation of samples of the present fabric, it was discovered that a heat-setting temperature more than about 10% above the recommended temperature resulted in undesirable stiffness. Example 2 [0038] An imaged nonwoven fabric made in accordance with Example 1 , wherein the alternative a blend ratio of 75 percent weight base fiber and 25 percent weight fusible fiber were employed. Example 3 [0039] An imaged nonwoven fabric made in accordance with Example 1, wherein the alternative a blend ratio of 50 percent weight base fiber and 50 percent weight fusible fiber were employed. Example 4 [0040] An imaged nonwoven fabric having a before dyeing-basis weight of three-ounces per square yard was prepared using a fiber blend of 90 percent weight of base fiber to 10 weight percent fusible fiber. The base fiber for this blend was comprised of a Wellman 472, a 1.2 denier polyester staple fiberand the fusible fiber was a Wellman 712P, a sheath/core copolyester/polyester bicomponent fiber. A heat setting temperature of 130° C. was suitable for fabrics containing this fusible fiber., Steam dry cans were set at 130° C. for drying and heat setting the fabrics after entangling and imaging, as illustrated in FIG. 1 and utilizing an entangling drum 12 as depicted in FIG. 2. Example 5 [0041] An imaged nonwoven fabric made in accordance with Example 4, wherein the alternative a blend ratio of 75 percent weight base fiber and 25 percent weight fusible fiber were employed. Example 6 [0042] An imaged nonwoven fabric made in accordance with Example 4, wherein the alternative a blend ratio of 50 percent weight base fiber and 50 percent weight fusible fiber were employed. Example 7 [0043] An imaged nonwoven fabric made in accordance with Example 1, wherein the alternative a blend ratio of 85 percent weight base fiber and 15 percent weight fusible fiber were employed on a image transfer device having a patterned termed “pique” and depicted in FIG. 3. Example 8 [0044] An imaged nonwoven fabric made in accordance with Example 1, wherein the alternative a blend ratio of 85 percent weight base fiber and 15 percent weight fusible fiber were employed on an image transfer device having a patterned termed “octagon and square” and depicted in FIG. 4. Example 9 [0045] An imaged nonwoven fabric made in accordance with Example 1, wherein the alternative a blend ratio of 85 percent weight base fiber and 15 percent weight fusible fiber were employed on a image transfer device having a pattern termed “20×20”, which refers to a rectilinear forming pattern having 20 lines per inch by 20 lines per inch configured in accordance with FIGS. 12 and 13 of U.S. Pat. No. 5,098,764, except mid-pyramid drain holes were omitted. Drain holes are present at each corner of the pyramids (four holes surrounded each pyramid). The “20×20” pattern is oriented 45 degrees relative to the machine direction, with a pyramidal height of 0.025 inches and drain holes having a diameter of 0.02 inches. Example 10 [0046] An imaged nonwoven fabric having a before dyeing-basis weight of 3.5 ounces per square yard was prepared using a fiber blend of 85 percent weight of base fiber to 15 weight percent fusible fiber. The base fiber for this blend was comprised of an “ECHOSPUN” Wellman recycled PET fiber of 1.8 denier and the fusible fiber was a KOSA 252, a sheath/core copolyester/polyester bicomponent fiber of 3.0 denier. The entangling drum 12 used was provided with a pattern referred to as “12×12”, which refers to a rectilinear forming pattern having 12 lines per inch by 12 lines per inch configured in accordance with FIGS. 12 and 13 of U.S. Pat. No. 5,098,764, except mid-pyramid drain holes are omitted. A heat setting temperature of 184° C. was suitable for fabrics containing this fusible fiber, using a through-air drier as depicted at 22 in FIG. 1. Example 11 [0047] An imaged nonwoven fabric made in accordance with Example 10, wherein the alternative the imaged nonwoven fabric was not subjected to elevated temperature, and therefore the fusible fiber was not activated. Example 12 [0048] An imaged nonwoven fabric having a before dyeing-basis weight of 3.0 ounces per square yard was prepared using a fiber blend of 85 percent weight of base fiber (the base fiber itself comprised of a blend of 59 weight percent “MODAL” Lenzing high-modulus rayon of 1.5 denier to 41 weight percent Wellman 472, a 1.2 denier polyester staple fiber) to 15 weight percent fusible fiber. The fusible fiber was a KOSA 252, a sheath/core copolyester/polyester bicomponent fiber of 3.0 denier. The entangling drum 12 used was in a configuration referred to as “33×28”, which refers to a rectilinear forming pattern having 33 lines per inch by 28 lines per inch configured in accordance with FIGS. 12 and 13 of U.S. Pat. No. 5,098,764, except mid-pyramid drain holes are omitted. A heat setting temperature of 190° C. was suitable for fabrics containing this fusible fiber, using a through-air drier as is commercially available. Example 13 [0049] An imaged nonwoven fabric made in accordance with Example 12 , wherein the alternative the imaged nonwoven fabric was not subjected to elevated temperature, and therefore the fusible fiber was not activated. [0050] Samples 4 and 5 were found to be soft and drapeable. Sample 6, containing 50 weight percent of the fusible fiber was stiff. This was attributed to the higher content of the polyester fusible fiber. [0051] As shown in Table 1, Examples 1, 2, 3, and 4 (Samples 1 to 4) were successfully jet dyed after heat setting then tested for appearance after repeated home launderings as per test protocol AATCC 124-1996. No application of chemical binders was required to obtain the positive results. These examples were also tested under protocol Federal Test Method 191A, Method 5206, “Stiffness of Cloth, Drape and Flex, Cantilever Bending Method”, the results provided in Table 2. Table 3 presents standard ASTM fabric quality test results for Examples 7 through 9 (Samples 7 to 9). Examples 10 through 13 were tested under ASTM D35 11-82 for abrasion resistance. The results of activating the fusible fiber versus not activating the fusible fiber are shown in FIGS. 8 through 11. Example 10, depicted in FIG. 8, and Example 12 depicted in FIG. 10, both exhibits the reduction in pilling caused by abrasion against a high friction surface. Example 11, depicted in FIG. 9, and Example 13, depicted in FIG. 11, which are the corresponding imaged nonwoven fabrics whereby the fusible fiber is not activated, shows that significant abrasion and loss of image quality are apparent. TABLE 1 Sample ID 1st Wash Cycle 5th Wash Cycle 1 3.5 3.5 2 3.5 3.5 3 3 5 4 3 5 [0052] [0052] TABLE 2 Sample 1 Sample 2 Sample 3 Sample 4 Length Width Length Width Length Width Length Width 9.1 4.9 10.7 5.7 9.3 4.2 9.3 4.7 8.3 4.7 11.2 6.2 9.1 4.2 9.7 5.0 8.5 4.7 11.5 6.2 8.7 4.3 9.1 4.9 8.2 4.8 11.8 6.5 9.5 4.3 9.1 4.8 8.0 4.6 10.7 6.5 9.1 3.8 9.3 4.8 8.4 4.7 11.2 6.2 9.1 4.2 9.3 4.8 average average average average average average average average [0053] [0053] TABLE 3 Test Sample Basis Weight Brush Pill Rating Tensile-MC Tensile-CD Elongation-MD Elongation-CD Sample 7 - Before 3.70 1 64.7 47.3 67.5 109.3 Fusible Activation Sample 7 - After 3.89 3 72.6 46.6 39.2 115.9 Fusible Activation Sample 8 - Before 3.48 1 69.1 50.8 75.1 130.1 Fusible Activation Sample 8 - After 3.53 3 70.8 48.2 41.6 118.3 Fusible Activation Sample 9 - Before 2.37 1 48.5 24.4 53.0 132.2 Fusible Activation Sample 9 - After 2.71 4 52.9 20.5 41.6 123.1 Fusible Activation [0054] From the foregoing, it will be observed that numerous modifications and variations can be affected without departing from the true spirit and scope of the novel concept of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated herein is intended or should be inferred. The disclosure is intended to cover, by the appended claims, all such modifications as fall within the scope of the claims.

A nonwoven fabric, and method of production, are disclosed, wherein the nonwoven fabric comprises textile length fibers with a portion being thermally fusible. The fabric exhibits sufficient durability to withstand commercial dyeing processes, with the resultant fabric finding widespread applicability by virtue of its durability and aesthetic appeal.

CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part of application Ser. No. 09/276,063, filed Mar. 25, 1999, now U.S. Pat. No. 6,286,212, entitled “Thermally Conductive Material and Method of Utilizing the Same”, which is a continuation-in-part of U.S. Ser. No. 08/654,701, filed May 29, 1996, now U.S. Pat. No. 5,930,893, issued Aug. 3, 1999, entitled “Thermally Conductive Material and Method of Using the Same.” BACKGROUND OF THE INVENTION This invention relates to a thermally conductive compound and method of constructing a low impedance, thermal interface/joint between an electronic component and a heat sink the compound having desired adhesive and closure force characteristics. Electrical components, such as semiconductors, transistors, etc., optimally operate at a pre-designed temperature which ideally approximates the temperature of the surrounding air. However, the operation of electrical components generates heat which, if not removed, will cause the component to operate at temperatures significantly higher than its normal operating temperature. Such excessive temperatures can adversely affect the optimal operating characteristics of the component and the operation of the associated device. To avoid such adverse operating characteristics, the heat should be removed, one such method being a conduction of the heat from the operating component to a heat sink. The heat sink can then be cooled by conventional convection and/or radiation techniques. During conduction, the heat must pass from the operating component to the heat sink either by surface contact between the component and the heat sink or by contact of the component and heat sink surfaces with an intermediate medium. In some cases, an electrical insulator must be placed between the component and heat sink. Thus, a heat-conducting path must be established between the component and the heat sink surfaces with or without an electrical insulator therebetween. The lower the thermal impedance of this heat conducting path the greater the conductivity of heat from the component to the heat sink. This impedance depends upon the length of the thermal path between the component and heat sink as well as the degree of effective surface area contact therebetween. As the surfaces of the heat sink and component are not perfectly flat and/or smooth, a full contact of the facing/mating surfaces is not possible. Air spaces, which are poor thermal conductors, will appear between these irregular mating surfaces and thus increase the path's impedance to conduction. It is thus desirable to remove these spaces by utilizing a heat conducting medium, the medium designed to contact the mating surfaces and fill the resulting air spaces. The removal of these air spaces lowers the path's thermal impedance and increases the path's thermal conductivity. Thus, the conduct of heat along the thermal path is enhanced. Mica insulators with silicone grease thereon, the silicone grease containing “heat conducting particles,” such as a metallic oxide, have been inserted between the component and heat sink to establish a thermal path. The grease can also be applied directly to the mating surfaces in an attempt to fill the resulting voids therebetween. However, the non-soluble grease is messy and can contaminate the equipment, clothing and personnel. Another proposed solution was to coat a polymeric insulating gasket with a metallic oxide thereon, the gasket being inserted between the component and heat sink during assembly. Such oxides can be expensive, toxic and adhesion to the gasket can be difficult. Moreover, the gasket may not fully mesh with the irregular mating surfaces of the component and heat sink resulting in undesirable, inefficient air spaces therebetween. The use of a compound comprising a paraffin wax with a softener such as petroleum jelly as the intermediate medium has been proposed in the Whitfield U.S. Pat. Nos. 4,299,715, 4,473,113, 4,466,483. The softener is intended to make the compound less brittle so it will not crack when coated onto the intermediate flexible insulator. However, this compound changes from a solid to a liquid state at the component's normal operating temperature which decreases its thermal conductivity. Also, the compound tends to flow away from the thermal path/joint which increases the impedance of the thermal path. Moreover, this flow can contaminate the surrounding surfaces. Also, the use of softeners makes the resulting compound more susceptible to abrasion or chemical solvents. Thus, the compound can be rubbed off its substrate carrier during handling or component cleaning. Also, the “blocking temperature” of the compound is lowered, i.e., the temperature at which the coated carriers will stick to each other. (If the blocking temperature is equal to or lower than the room temperature, the coated carriers will stick to each other.) Also, the softeners make the compound stickier which makes it difficult to manipulate and susceptible to collection of foreign matters thereon. Such foreign materials can lead to component malfunctions, if not failure. In response thereto I have invented a method of selecting a compound for establishing an efficient thermal joint between the surfaces of an electrical component and heat sink. With cognizance of a normal operating temperature of a selected component, the compound is selected to melt only during initial component operation by either external heat or a component temperature well above the component's normal operating temperature. Once initially liquified or sufficiently deformable, the clamping pressure of the component to the heat sink causes the compound to fill the spaces resulting in the thermal path between the heat sink and the component. This action presents a thermal path of low impedance which initiates an effective conduct of the heat from the component to the heat sink. The component temperature then falls to a temperature below the compound melt temperature and to its normal operating temperature which causes the compound to resolidify. Upon subsequent operation of the component, the component reaches only the components normal operating temperature as the previously established compound joint formed during initial component operation remains in a solid state. As the compound does not melt during subsequent component operation, a higher thermal conductivity is maintained. Moreover, as compounds of high molecular weight can be used in the above process, a higher thermal conductivity will result with or without the use of heat conductive particles. I have also invented a simple method of applying a compound to a heat sink which is simple, cost effective and easy to use. The method basically utilizes a rod of preselected compound and cross section which is depressed against the heat sink for a selected length of time to leave a deposit of material thereon. The selection of certain characteristics of the compound material constricts the deposit to the cross-sectional area of the rod. The method is not limited to the particular compounds described herein. As above discussed, the shorter the path between the component and heat sink the lower the thermal resistance. Thus, the lower the force required to reduce the thickness of the thermal compound interface the easier to reduce the thermal resistance of this path. This force must be coordinated with the closure force. By closure force I mean the aforementioned clamping pressure/force needed to initially join the component, thermal interface and heat sink. It is known to have a film, e.g., a diamond film, along the component interface which serves as a “heat spreader”. Any localized heat on the component will be dispersed along the film in all directions (isotropic) which enhances the transmission of the heat from the component to the heat sink. The diamond films may be rigid, inflexible and fragile. In order to manipulate these films the film must have a thickness of at least a few hundred microns. However, these films result from a slow chemical vapor deposition process. The deposit process is a slow one, i.e., only about one micron/hour. In order to take advantage of the basic thin film and its high thermal conductivity, it is desirable to have a thermal interface compound that can interface the film with the component and heat sink at a very low closure force. Otherwise, the film will break at a high closure force. It is also desirable that the interface material become flowable during initial component operation and/or deformable under low closure forces but not so flowable as to migrate away from the interface area. However, the interface material should not be so viscous that it requires high closure forces for component mounting which could damage the component or any associated “heat spreader” film. Thermal resistance and closure forces are thus related. Since thermal resistance is lower when the thermal path is reduced, it is desirable that a very thin interface be formed at low closure forces. Otherwise, a large closure force may damage the component and/or intermediate film. Most electrical components cannot withstand closure forces of more than 10-20 psi. The diamond film is even more sensitive to closure forces. Known interface materials require hundreds of psi to achieve a path having a low thermal resistance. Thus, a closure force problem exists. It is noted that the ASTM test standard on thermal phase change materials is done at 438 psi, well above the maximum closure force that should be applied to an electronic component. Thus, the problem may not be a recognized one. It is desirable to have an interface material at room temperature that will change phase to a flowable state at elevated temperatures and/or deformable at low closure forces. The material should not be so viscous that it requires large closure forces to deform so as to obtain the desired component interface. The material should not migrate away from the component/heat sink under elevated temperatures or under closure forces. A very thin thermal interface at low closure forces should be created to preclude damage to the component and/or heat sink and/or any intermediate film therebetween. The thermal material need not be used with a substrate carrier. A substrate increases the distance between the electrical component and the heat sink and thus increases the thermal resistance. Thus, the material should be free standing if a carrier is not desired. Currently, pressure sensitive adhesive (PSA) strips along the edges of the thermal interface material adhere the thermal interface to the heat sink. However, these strips can only partially cover the interface material as the strips have high thermal impedance and increase the thermal path. At times these strips do not provide sufficient adhesion. Moreover, foreign matter can migrate between the PSA strips and the heat sink which increases thermal resistance. Thus, the thermal interface material should be flexible, easy to handle at room temperature and dry to the touch. It also should flow at a temperature above room temperature and deform under low closure forces. The material should adhere to the heat sink and component surfaces but be removable therefrom by heat application. Also, the interface material should be able to be stored on the heat sink for transport and subsequent use. In response thereto I have arrived at a process for selecting an interface compound that meets the above objectives as well as presents the following characteristics: 1. The interface material can be manufactured in sheet or roll form, cut to a desired shape and then placed on the heat sink for subsequent sandwiching between the electrical component and the heat sink or otherwise compressed on the heat sink for adherence upon cooling. 2. The interface material can be melted by either external heat or the heat generated by the initial component operation. 3. Upon cooling below its melt/phase change temperature, the material provides sufficient adhesion to maintain the electric component to the heat sink. Thus, mechanical fasteners, e.g., PSA strips, are not required. 4. As long as the operating temperature of the component remains below the melt/phase change temperature of the thermal interface material, the component remains firmly adhered to the heat sink. 5. The projection of external hot air onto the component will increase the thermal interface temperature so as to reduce the adhesive bond for component removal. It is therefore a general object of this invention to provide an improved compound and method of selecting the same for reducing the impedance to heat flow through a thermal joint established between an electrical component and a heat sink while providing an effective adhesive bond. Another object of this invention is to provide a compound and method, as aforesaid, which is initially liquified/deformable during initial component operation but remains in a solid state during subsequent component use. A further object of this invention is to provide a compound and method, as aforesaid, wherein the compound does not melt at a subsequent normal operating temperature of the component but can be removed upon the application of external heat at a higher temperature thereto. A more particular object of this invention is to provide a compound, as aforesaid, which is easily coated onto a substrate carrier for placement between the component and heat sink. Another object of this invention is to provide a compound and method, as aforesaid, which provides a high thermal conductivity relative to previous compounds utilizing material softeners. A further object of this invention is to provide a compound, as aforesaid, which is easy to manipulate and does not contaminate surrounding personnel and equipment. Another particular object of this invention is to provide a compound, as aforesaid, which includes a material therein so as to avoid the problems associated with material softeners. A further object of an embodiment of this invention is to provide a compound which initially adheres the electrical component to the heat sink at a low closure force. Another object of this invention is to provide a compound, as aforesaid, which deforms under low closure forces of the component to the heat sink. Still another object of this invention is to provide a compound, as aforesaid, which may be effectively utilized with “heat spreader” type films. Another particular object of this invention is to provide a compound, as aforesaid, which can be used in sheet, roll or rod form and on printed circuit boards. A further object of this invention is to provide a method of depositing a pad of compound acting as a phase change material on a heat sink. Another object of this invention is to provide a method, as aforesaid, which produces a vacuum between the rod and heat sink to constrict the deposited compound material to the cross-sectional configuration of the end of the rod. A particular object of this invention is to provide a method, as aforesaid, wherein the rod remains in stable form after repeated application. Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, an embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic view of the irregularities of the mating surfaces of an electrical component and a heat sink; FIG. 2 is a diagrammatic view, on an enlarged scale, of a semiconductor and a heat sink with a compound coated on an intermediate carrier substrate; FIG. 3 is a diagrammatic view showing the compound, as coated on a carrier substrate, the substrate being positioned between the mating surfaces of an electrical component and heat sink; FIG. 4 illustrates first and second time/temperature curves of an electrical component in connection with using the selected thermally conductive material; and FIG. 5 is a diagrammatic view illustrating a method for depositing a pad of the compound on a heat sink. DESCRIPTION OF THE PREFERRED EMBODIMENT Turning more particularly to the drawings, FIG. 1 diagrammatically shows a surface 210 of an electrical component 200 , e.g., as a transistor, semiconductor, etc., facing a heat sink 100 surface 110 . It is understood that such surfaces 110 , 210 are not smooth, such irregularities being diagrammatically shown. Upon mating the surfaces 110 , 210 , air spaces will appear between these irregular surfaces. As air is a poor conductor of heat, it is desirable to fill these resulting voids with a heat conducting medium so as to lower the impedance of the thermal joint/path 1000 established between the component 200 and heat sink 100 . The lower the impedance of the thermal path the more efficient the conduct of heat from component 200 to heat sink 100 . FIG. 2 shows a compound carrier in the form of a flexible gasket 300 which may act as an electrical insulator between surfaces 110 , 210 . The gasket 300 may also be embedded with metallic oxide/heat conducting particles so as to enhance the heat conductivity along the thermal path 1000 . However, as the gasket 300 alone may not fill all the air spaces appearing between the irregular mating surfaces 110 , 210 , the gasket 300 can act as a substrate carrier for a compound designed to fill these resulting air spaces. I have devised a method of selecting a compound which can either be coated onto the facing surfaces of the component 200 or heat sink 100 or onto opposed surfaces of an intermediate carrier substrate 300 so as to optimally fill the resulting air spaces and present an efficient thermal joint between the component 200 and the heat sink 100 . The compound is selected so that it can be coated onto a substrate 300 and inserted between the component 200 and heat sink 100 during assembly. As the compound is initially in a solid state, it does not fill all the resulting voids between the mating surfaces 110 , 210 . Thus, during initial component 200 operation, the thermal path is an inefficient one. This inefficiency causes the component 200 to reach a temperature above its normal operating temperature as well as the melt temperature of the chosen compound. The operating component 200 will thus heat the compound to its melt temperature causing the compound to liquify or deform and fill the voids between the nominally mating surfaces 110 , 210 of the component 200 and the heat sink 100 . Once the voids are so filled an efficient thermal joint 1000 is established which enhances the conductivity along the thermal joint 1000 . In turn, more heat flows from the component 200 to the heat sink 100 such that the component temperature is reduced to its normal operating temperature. During this component cool down, the compound temperature drops below its melt temperature which returns the compound to its solid state, the previously established joint 1000 being maintained. Upon subsequent operation of the electrical component 200 the component 200 will heat only to its normal operating temperature as the previously established thermal joint 1000 conducts heat from component 200 to heat sink 100 . The compound will not liquify/deform as the normal operating temperature of the component 200 remains below the compound's melt temperature. As the compound cannot liquify, it maintains a higher thermal conductivity relative to the conductivity of its liquid state. Moreover, as the compound will not flow away from the thermal joint the joint integrity is maintained. Utilizing the above principles various compounds can be selected so as to achieve an efficient thermal joint 1000 . As a first example, a compound comprises 95 parts of a paraffin wax having a 51° C. melting point. To this paraffin I add five parts by weight a 28% ethylene/vinyl acetate copolymer hardener with a 74° C. melting point. One such copolymer is an Elvax resin available from the Dupont Company, Polymer Products Division of Wilmington, Dela. The element proportions are selected so that the resulting compound will have a melt temperature above the normal operating temperature of the component. Upon heating the compound to a temperature beyond its melt temperature, i.e., approximately 52° C., the viscosity of the compound will decrease so that a carrier 300 can be dip coated into the compound. The carrier can be a 0.002 inch thick polymer insulating material with or without heat conducting materials impregnated therein. The compound resolidifies into a thin layer about 0.001 inch thick on the opposed surfaces of the polyamide carrier 300 . When the temperature of the electrical component reaches 80° C., the compound is heated beyond its melt temperature, i.e., 52° C., so as to fill the empty spaces appearing between the heat sink 100 and component 200 surfaces. This compound action will reduce the thermal impedance of the thermal joint 1000 between the component 200 and heat sink 100 such that the component 200 will eventually return to its normal operating temperature. (The thermal impedance of this compound is approximately 0.179 C/W.) As the component must initially operate beyond the compound melt temperature so as to heat the compound to its melt temperature, it is understood that by choosing a wax and copolymer with specific melt temperatures, the melt temperature of the resulting compound can be varied and chosen according to the initial and normal operating temperatures of the component. FIG. 4 diagrammatically relates the temperatures of the component 200 to the melt temperature of the compound. As shown in FIG. 4, the first heat up curve 900 of the component 200 shows the component reaching a maximum temperature at T 1 . Upon reaching this temperature, the compound will be heated beyond its melt temperature T 2 so as to become sufficiently deformable to fill the spaces between the component surface 210 and heat sink surface 110 . Upon these spaces being filled, the thermal impedance of the path between the component and the heat sink is reduced which reduces the temperature of the component 200 to the desired component operating temperature T 3 , this temperature being below the chosen compound melt temperature T 2 . Upon a subsequent operation of the component 200 , the curve 950 shows the temperature of the component 200 reaching a maximum of T 3 , the component's normal operating temperature. As the temperature of the component 200 will not increase beyond T 3 , due to the previously established efficient thermal joint 1000 , the component temperature T 3 remains below the compound melt temperature T 2 . Thus the compound will remain in a solid state during normal operation of the component, it being understood that the compound will have a higher conductivity than when in a liquid state. Thus, a more efficient conduct of heat through thermal joint 1000 will occur as compared to the prior art in which the compound is designed to liquefy. Moreover, as the resulting compound will remain in a generally solid state at the normal operating temperatures of the component 200 and not phase into a liquid state the problems with the prior art have also been addressed, e.g., the elimination of the messy liquids and a compound flow away from the thermal joint. It is also noted that as the initial heat up curve allows the component to heat beyond its normal operating temperature, compounds having high melt temperatures can be used. Thus, compounds having high molecular weights can be used, it being understood that such compounds have a better conductivity as opposed to compounds of lower molecular weight. For example, a synthetic wax having a melt point of 100° C. and a molecular weight of approximately 1000 can be used, the wax being a type of wax known as a Fischer-Tropsch wax. The wax was coated onto a carrier 300 as above described. Upon initial operation of a semiconductor the semiconductor reached a temperature of 105° C. which melted the wax. Upon the wax establishing the thermal joint the temperature of the semiconductor fell to 82° C. The thermal conductivity of the wax at 150° C. is 0.191 W/mK while at 82° C. is 0.242 W/mK. As the compound will not reach its melt temperature during subsequent use, the thermal conductivity of the joint 1000 will be greater than if the compound is liquefied as found in the prior art. Accordingly, it is desirable to have the electrical component initially heat to a temperature considerably above its normal operating temperature so as to melt the compound. Thus, the addition of the Elvax to the wax or the use of a wax of a high molecular weight can be used which results in a material which initially presents an inefficient thermal joint. (It is noted that the compound should also be relatively hard and undeformable by the normal mounting/clamping forces utilized in mounting the component to the heat sink.) This inefficient thermal joint allows the component 200 to heat to a temperature which will melt the component so as to establish a thermal joint between the component 200 and heat sink 100 . This joint will reduce the component temperature and allow the compound to resolidify. Due to this joint 1000 presence, the component 200 will not reach a temperature to subsequently melt the compound. Thus, the integrity of joint 1000 is maintained. Moreover, the use of the Elvax hardener in the compound or use of a medium of high molecular weight solves the problems associated with the prior art. Although the above has been discussed without the use of any heat conducting particles in the compound or barrier, it is also understood that heat conducting particles may also be used which may further decrease the thermal impedance of the thermal joint/path. As above set forth, I have described an interface compound in which the heat needed for melting may be generated by the component itself. Also, it is advantageous to use externally applied heat to either initially cause a flow and/or reflow the compound interface. The application of external heat to the compound interface can be utilized as most electrical components can withstand externally applied heat above its maximum operating temperature. It is also desirable that when the component cools and the compound interface returns to a solid state that it presents an adhesive characteristics sufficient to adhere the component and heat sink thereto. It is also advantageous that the compound be deformable at low closure forces so as to assist the migration of the compound into the air spaces whether prior to or after the compound is melted. It is also advantageous to vary the compound interface formulation so that the compound interface can have various adhesion characteristics at different temperatures for use with various low closure forces. In some applications the components and the heat sink must be separated by an electrically insulating medium. In other applications it is not required and in these cases a thermally conductive compound can also be electrically conductive. To achieve these characteristics I have discovered one compound which comprises 25 parts of paraffin wax having a melting point of 51° C. To this paraffin I add six parts by weight of 28% ethylene/vinyl acetate copolymer having a melt temperature of approximately 74° C. Such copolymer is an Elvax resin available from the DuPont Company. To this mixture 69 parts by weight of zinc oxide heat conducting particles may be added. These ingredients are mixed together. These proportions are found to provide a compound having a melt temperature of about 57° C. as well as provide the following values: A thermoplastic material with sufficient cohesiveness which can be laminated, molded, die-cut and physically handled during normal installation without disintegrating. A thermoplastic material which can firmly hold electric components to heat sinks. The adhesive bond between the components and the aluminum heat sink is about 25 psi. A thermoplastic material which is easily deformed under low closure forces on electronic components to form a very thin interface, the closure forces being below a fracture force damaging the component. A thermoplastic material which will not migrate away from the interface area during closure forces and subsequent component operation. I have simultaneously achieved the above characteristics with the last above-described formulation. It is noted that the reduction of the wax from the first described example from 95 parts to 25 parts along with an increase of the copolymer from five to six parts, increases the adhesion characteristic of the compound. My invention is, however, not to be limited to the above-described example as the materials of various melt temperature and proportions can be used to vary the compound melt temperature depending on the operating temperature of the component to be used thereon. The melt temperature in the latter example approaches that of the wax (51° C.) as the proportion of wax is greater than the co-polymer. (Formulas for computing a compound melt temperature based on the melt temperatures of the compound parts are known.) For example: MT =( MT 1 ×% M 1 )+( MT 2 ×% M 2 ) where MT=compound melt temperature MT 1 =material 1 melt temperature MT 2 =material 2 melt temperature Thus, various modifications may be made by choosing different characteristics, e.g., the melt points for the paraffin and the acetate copolymer. For example, if the wax and copolymer components had the same 74° C. melt temperature, the compound will have a 74° C. melt temperature. The adhesion will be about 25 psi up to this 74° C. melt temperature. If, however, the melt temperature of the paraffin is considerably higher (100° C.) than the copolymer, the adhesiveness of the compound would begin to diminish from about 25 psi at 74° C. to almost 0 psi at 100° C. as the adhesive quality decreases after the copolymer melt temperature is reached. Although an increase in the copolymer parts will increase the adhesion characteristics, this increase must be balanced against the increase in viscosity and stickiness of the compound. Also any increase in the wax percentage in the compound must be balanced against the increase in fluidity of the resulting compound. It is also understood that particles which are electrically conductive can be utilized. The use of electrically conductive metal particles rather than the electrically insulating metal oxide particles can enhance the heat transfer through the interface material. As such, I have used very small size metallic silver particles instead of the zinc oxide particles in the above example. The same volume as the volume of zinc oxide was used. In both examples, the above features were obtained. As an example of use, a compound interface similar to the one above described (25 parts wax/six parts copolymer) was screen printed via a stencil of appropriate thickness onto a preheated aluminum heat sink to present a 0.005 inch pad. The heat sink was preheated to a temperature above the reflow/melt temperature of the compound. When the heat sink cooled to room temperature the thermal pad was firmly adhered to the heat sink surface. The above compound interface can also be extruded in bulk, e.g., to form rods of material having various cross sections, e.g., various square, round, etc. shapes. The rod is pressed against a heat sink preheated above the compound melt temperature. This contact and removal of the rod deposits a pad of the thermal material thereon. The electric component is then pressed against the thermal pad which further flows the thermal material. Upon cooling, a very low thermal resistance of the thermal interface occurs between the heat sink and component with a bead 240 of the compound interface formed around the exterior of the component at its juncture with the heat sink. The compound interface firmly adheres the heat sink to the component. The above interface may be first applied to the heat sink for later connection of the component thereto upon heating the heat sink and interface material to the melt temperature with external heat or using the heat of component operation. The interface may be utilized with hot melt glue equipment as well as in computer controlled syringes for deposit on the desired heat sink surface and/or component surface. This resulting bead precludes dirt from entering the thermal interface. Another example is that the compound interface can be screen printed onto circuit boards 900 . The soldering paste can then be screen printed onto the board. A clamping device then clamps the components to the circuit board with the compound interface therebetween. The closure force provided by the clamping device may initially cause deformation to the underlying compound to cause an initial compound migration/flow. The board can then be placed in a soldering oven which simultaneously solders the components and causes the compound interface to flow creating the desired thermal interface. The above compound may also be utilized with computer controlled syringes or with melt glue equipment to deposit the compound interface on the desired surface. I have also invented a method for efficiently depositing a pad of the compound interface on a heat sink which can be utilized with various types of interface materials. Thermal interface materials, e.g., the above-identified materials, may be formed into sheets or rolls of material which are then die-cut and supplied on sheets or rolls. This method requires significant labor. If due-cut, the interface material must be first manufactured according to a desired configuration and then manually installed which includes the following operations: (1) The interface material must be between two release liners; (2) The interface material with release liners must then be die cut to the desired configuration; (3) The release liners must be removed prior to installation; (4) The material must then be installed on the heat sink. Expensive equipment must be used to dispense the phase change material on the heat sink. This equipment requires frequent clean up and maintenance, and is not easily adaptable to modification. Dispensers, which pre-melt the phase change material inside the dispenser, for subsequent “painting” of the material onto the heat sink surface are also known. The present invention provides a method which uses a preselected material formulation that remains form stable even after repeated applications. As such the material allows a simple method allowing simple equipment to be used, i.e., a simple vertically reciprocative arm to apply the material to preheated heat sink passing thereunder. The above-described phase material can be any material as long as it is highly thixotropic, e.g., a wax-based thermoplastic (not thermosetting) so that it can readily melt and resolidify. This phase change material is extruded, molded or otherwise formed into a rod having a desired cross-section corresponding to the configuration of the heat sink. The rod 1100 can then be manually depressed onto the heat sink 1200 and be installed into a vertically reciprocative arm 1300 , the arm being either manually controlled or computer controlled in a timed up and down movement. The heat sink 1200 to which the pad of thermal interface material may be preheated by any convenient method, e.g., heat lamp, hot plate, conveyor oven 1600 , etc. The heat sink should be heated to a temperature above the phase change temperature of the selected material of the above thermal compound rod but should not exceed the maximum operating temperature of this thermal interface material. For a material with a 52° C. phase change temperature, the minimum heat sink 1200 temperature should be about 60° C. so as to ensure that the heat sink 1200 is adequately heated to melt the thermal material. (Most wax containing materials should not be heated above about 200° C. so this would be the maximum heat sink temperature.) The exact temperature is not critical. Once the heat sink 1200 is heated, the rod 1100 is simply depressed vertically against the heat sink 1200 for a few seconds, then removed. The viscoelastic properties of most phase change thermal materials causes the tip of the rod 1100 to deform when melted and pressed against a heated surface. Normally, repeated application of a rod tip to heated surfaces makes the tip become progressively larger and deformed. However, in the present invention the thixotropic and viscoelastic properties of the thermal material are chosen to prevent the melted material at the rod tip from flowing beyond the dimensions of the rod. Such material will create a vacuum between the molten tip and the heated heat sink 1200 surface. The thermal material is chosen to have a highly thixotropic characteristic such that the molten material of the rod tip will not flow laterally under its own weight. Thus, when the rod is pressed against the heated heat sink surface the phase change material at the tip of the rod melts. The weight of the material causes a deposit on the heat sink as a vacuum has been formed between the rod tip and heat sink 1200 . However, as soon as the molten material tries to flow beyond the edges of the tip of the rod, the air pressure about the outside of the rod precludes the thixotropic material from flowing therebeyond. Thus, the molten material is constricted to the perimeter of the cross section of the rod. As such, removal of the rod tip from the heat sink helps to retain the shape and size of the rod tip for subsequent application. Because of these preselected properties of the thermal compound, repeated applications to the heat sink does not deform the rod tip and produces essentially the same size and thickness of a deposited thermal pad with each application. Thus, an entire rod can be used with the final deposited thermal pad on the heat sink being substantially the same as the first deposited pad. Upon movement of the rod away from the heat sink 1200 , a pad of molten, thermoplastic, thermal material, corresponding to the cross section of the rod end is deposited on the heat sink. Due to the combination of the air pressure, vacuum and thixotropic characteristic of the material, the rod material will not drip, migrate or leave a “peak” of material vertically projecting from the deposited thermal pad. After deposit, two alternative courses of action may follow: 1) The heat sink is allowed to cool, shipped and stored for later installation of the electronic component on the heat sink. In this case heat from component operation will again reflow the thermoplastic thermal material and create a very thin, low thermal resistance thermal interface assuming the above-identified material is utilized. 2) While the thermal material is still molten, the electronic component may be pressed against the molten thermal material such that the material forms a very thin thermal interface between the heat sink and component. When the heat sink cools below the phase change temperature of the thermal compound, the thermal interface material, as above described, solidifies and firmly adheres the component to the heat sink. The assembly can now be shipped or stored without worry about the shelf life or thermal degradation due to deterioration of a pressure sensitive adhesive on the thermal pad surface. These thermal material rods can be used manually or in simple, automatic equipment which holds the rods vertically and bring the rods down onto the conveyed heated heat sink surface to achieve increased repeatability of position, force and dwell time of the rod on the heat sink. Thus, the same rod can be used for manual application as well as high-speed volume production. EXAMPLES OF THE MATERIAL A thermal compound is formed by mixing: 4.25 parts by weight of Paraffin Wax having a melt point of 52° C. 1 part by weight of Ethylene-Vinyl Acetate Copolymer (Elvax) having a melt temperature of 71° C. 11.5 parts by weight of finely divided Zinc Oxide powder In some cases a surface-active agent may be used as known to those skilled in the art. The amount of heating conducting particles can be varied over a considerable range. The amount of ZnO used in such formulations should be sufficient to make the viscosity of the material high enough that the material will not migrate or flow in typical electronics interface applications. The viscosity of the resulting compound, when in the molten state is approximately 80 to 100 poises. After thorough mixing the resulting thixotropic, highly viscous thermal material was formed into rods of material using an extruder. Rods 0.5×0.5″×8″ long were produced to create thermal pads as above described. The shape and size of the thermal pads produced by the rod was substantially the same at the end of the rod as at the beginning. The data below shows the typical operating parameters for use of the rods, i.e., a heat sink temperature of 65° C.; pressure on rod of five to 10 psi and a dwell time of one second resulting in a pad thickness of 0.003″. The temperature can vary considerably without great variation in the pad that is created on the heat sink. For example, utilizing the same material in connection with a heat sink temperature of 75° C.; a pressure on rod of five to 10 psi and a dwell time of one second resulted in a pad thickness of 0.003″. Accordingly, variations in the heat sink temperature may not have a significant effect on the resulting pad thickness. Testing can be easily accomplished to find a maximum heat sink temperature which does not affect the deposit. Accordingly, it is understood that various compound materials may be used with my method as long as the selection of the compound is guided by the above-desired characteristics. Once chosen tests can be conducted as to temperature, dwell time and viscosity to assure that an undesirable migration of the rod material does not occur beyond the perimeter of the rod cross section. Other objects and advantages of the above embodiments will become apparent from the above description taken in connection with the accompanying drawings. It is to be understood that while certain forms of this invention have been illustrated and described, it is not limited thereto, except in so far as such limitations are included in the following claims and equivalents thereof.

A method for depositing a thermal interface onto a heat sink including the selection of a highly thixotropic compound formed into a bulk form so as to present a tip which is melted upon contact with a preheated heat sink. The tip cross section preferably corresponds to the cross section of the heat sink. Upon depressing a tip of the compound against the heat sink a resulting vacuum therebetween cooperates with the ambient air pressure to preclude migration of the melted compound beyond the exterior of the tip such that the compound is deposited on the heat sink in the desired cross section form. Upon displacement of the tip from the heat sink, the ambient air pressure precludes subsequent migration of the compound onto the heat sink precluding a build up of the deposited material thereon. The component may then be subsequently pressed against the subsequent heat sink without a deformation of the compound tip precluding a subsequent deposit. Alternatively, after cooling the heat sink with pad may be reheated to melt the thermal pad for subsequent placement of a component thereon.

BACKGROUND OF THE INVENTION The present invention relates to a timing mechanism and more particularly to a timing mechanism wherein a short controlled "on" time is applied to a circuit load even though power is electrically applied to the timing mechanism switching system for an extended period of time by the timing mechanism. Most domestic electric and gas dryer appliances use a buzzer or alarm device to signal the consumer that the end of the drying program is complete. This signal is provided by the coast down time of the main appliance motor centrifugal switch which only continues for approximately one (1) second or less. It has been found that if clothes are not immediately removed from the dryer, wrinkles may set in the fabric, which in the case of many washables, is very undesirable. Therefore, most customers want a longer signal time (5-20 seconds) to make sure the housewife really hears the completed drying cycle signal. This short time signal is impossible to achieve from the main timing mechanism cam which usually has a speed of rotation of approximately 11/2-2 degrees per minute. The present invention, therefore, is directed to a timing mechanism which when electrically connected to a buzzer operates the buzzer in short pulses. SUMMARY OF THE INVENTION Accordingly there is provided a timing mechanism which in general comprises first cam means rotatably driven by a motor drive means, first electrical switch means responsive to the first cam means to be opened and closed in accordance with a first program of the first cam means, and means providing a second program of switching pulses comprising second cam means rotatably driven by the motor drive means, second switch means responsive to the second cam means, and a PTC thermistor circuit connected in series to the second switch means. DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic showing the principles of the invention. FIG. 2 is a view of a timing mechanism employing the invention. FIG. 3 is a top view of the timing mechanism of FIG. 2. DETAILED DESCRIPTION OF THE INVENTION Referring not to FIG. 1, in accordance with the present invention, a positive temperature coefficient thermistor (PTC) 10 is put in series with a switch 12 of a timing mechanism 14, the PTC thermistor in turn being connected in series to an alarm 16. As shown a resistor 18 is connected in parallel with alarm 16 to provide a bleeding resistor network 20. Using a clothes dryer as an example, at the end of the dryer drying cycle, switch 12 closes to make electrical contact with the PTC thermistor which has a resistance of approximately 300 ohms. This electrical connection energizes alarm 16 and bleeding resistor network 20 having a resistance of approximately 1200 ohms. The alarm immediately sounds. The current drawn by the alarm and bleeding resistor network causes the PTC to heat internally. When the internal temperature of the PTC reaches the Curie point or the switching point of the PTC material, an abrupt change in resistance occurs which shifts the PTC from 300 ohms to approximately 156,000 ohms. Because of the high resistance of the PTC most of the voltage potential across it drops and limits current flow to bleeding resistor network 20. This causes the alarm to stop making noise even though electrical power is still applied to the alarm circuit through the timing mechanism. By changing the value of resistor 18 the "on" time of the alarm can be changed. For example if a higher value resistor is used, the value of resistor network 20 is raised and the alarm will have a longer "on" time. Referring not to FIGS. 2 and 3 there is shown a timing mechanism 140 employing the features of the invention. Timing mechanism 140 includes a cam means 22 that is fixedly carried on shaft 24 that is rotatably driven by a motor 23 through a clutch (not shown) in a manner well known in the art. The cam means can be manually set by a knob (not shown) carried on the double D portion 26 of the shaft. Cam means 22 includes a first set of cams 1, 2, and 3 which open and close switches, which for the purpose of clarity are not shown. These cams and switches control the functions of an appliance, which in the illustrative embodiment is a clothes dryer. Cam 4 includes an outer cam profiles 36, a middle or neutral cam profile 38, and a series of narrow lobes 40 which form a series of notches 41 the bases of which form an inner cam profile 42. Lobes 40 make up about one fourth the circumference of cam 4. Collectively the three cam profiles bias a double throw switch 120. Switch 120 includes a cam follower 34 and fixed electrical contact blades 44 and 46. Fixed contact blade 46 carries an electrical contact 48 while cam follower 34 carries electrical contacts 50 and 52. Fixed contact blade 44 carries a PTC thermistor 100. Thus the combination of contact 52 and PTC thermistor 100 constitute the series connection of switch 12 and PTC thermistor 10 shown and described in FIG. 1. With particular reference to FIG. 3, there is shown an alarm means 160 and a resistor 180 carried by the timing mechanism and which are schematically illustrated in FIG. 1 as alarm 16 and resistor 18. Alarm means 160 includes a buzzer 64 having a coil 66 which when energized by an AC current causes an armature 68 to vibrate to produce a buzzing sound. One side of the alarm is connected to electrical terminal 70 through lead wire 69. Terminal 70 is connected to fixed electrical contact blade 44 which carries the PTC thermistor 100 (FIG. 2) while the other side is connected to terminal 72 of an AC power source (not shown). Resistor 180 is connected in parallel with buzzer 64 on one side through electrical terminal 72 and lead wire 74 and on the other side through electrical terminal 76 which is integral with electrical terminal 70. In operation, cams 1, 2, and 3 upon rotation control the function of the appliance. When cam follower 34 engages upper cam profile 36 of cam 4, electrical contacts 48 and 50 close to control another appliance function. When the cam follower 34 engages cam profile 38, switch 120 is completely opened. When cam follower 34 engages inner cam profile 42, electrical contact 52 closes with PTC thermistor 100 (FIG. 2) to operate buzzer 64. Cam follower 34 will remain on the inner cam profile of one of the notches 41 for 2 to 3 minutes during which time buzzer 64 will operate in the manner previously described with reference to FIG. 1 to provide a series of switching pulses thus causing the buzzer to turn off and on.

A timing mechanism has cams operating switches which control the functions of an appliance and another cam operating another switch supplying short pulses to a separate function such as a warning buzzer. A PTC thermistor is in series with the switch supplying the short pulses.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to cleaning tools and more particularly to tools for cleaning eavestroughs or rain gutters. 2. Description of the Related Art In many locations throughout the world, organic debris such as deciduous leaves, pine needles & moss present a continuous source of material which falls upon the roofs of houses. Such material ultimately is transported via wind and rain into the gutters causing damage to their structure and requiring continuous maintenance of the system. Presently there are 3 distinct methods for eliminating accumulated debris. One method employs screens or permeable drain covers. Though this method usually requires little upkeep once installed, these covers merely act as a ramp to transfer the debris onto shrubbery, walkways and flower beds. And even permeable covers become clogged and periodically require removal and cleaning. The second approach involves intrusive sub-systems which are difficult to install or retrofit. Besides the extensive labor of installing, none of them are compatible with the large variety of shapes that are presently in use. The third method of maintenance involves the use of some form of tool, usually, manual, but sometimes semi-automatic. Over the years the need for maintaining rain gutter systems has spawned a diverse array of gadgets, none of which provided an effective solution. Cleaning gutters using present technologies is not only an arduous and time consuming task, but also a potentially dangerous one. None of the available products allow a person to effectively clean a gutter from ground level. Therefore a person must either climb a ladder, or access the gutter by crawling along the roof. Both of these methods are potentially hazardous to one's health as well as to one's property. Even "professional gutter cleaners" are prone to these inherent dangers. Many of the tools, sub-systems or permeable covers that are available are not only inefficient at solving the problem, but often they are self-defeating or cause new problems. Numerous and sundry hand tools have been proposed for manually cleaning rain gutters. Many of these tools are only functional only if a person is stationed at roof level. This means that access to the gutter must either be accomplished by crawling along the eave of the roof or by positioning oneself atop a ladder or other elevated pedestal. Besides the inherent danger of such orientation, there is usually a great deal of difficulty negotiating shrubbery, fences and flower gardens. Soil which is directly adjacent to structures is notorious for being unstable in texture and therefore difficult to achieve a firm footing for a ladder. This not only invites the possibility of personal injury by the ladder toppling onto the ground; but there is also a good chance that a person will damage the gutter structure either by leaning the ladder against it or grasping the gutter to retain ones balance. The majority of tools designed to be operated at roof level do not facilitate the use of water because of the difficulty of manipulating an attached hose in such a precarious position. Cleaning debris from gutters also necessitates disposal of such debris. People who clean their gutters from roof level usually do not like to see the debris discarded haphazardly on to the walkways and shrubbery below them. Therefore some procedure must be incorporated to enable collection of the debris for transportation elsewhere. It is not uncommon in heavily wooded parts of the world for gutters to accumulate in excess of one hundred pounds of debris annually. Translated into volume this entails a sizeable amount to be transported. Whether a person uses a trash bag, wheelbarrow, bucket or any other similar container, the job is very inconvenient. If one uses a ladder, it must be picked up and restabilized after cleaning approximately four feet of the gutter. The wheelbarrow or container must also be moved. If one is accessing the gutter by crawling along the eave the job is probably no easier or safer. Even if one is not injured seriously, he or she can count on sore muscles, knees and hands once the job is done. Besides the danger and cumbersomeness of this form of gutter maintenance one can also add the messiness which leaves both body and clothes dirty and worn. Several tools have been proposed that attempt to solve the above problems by a tool that can access the roof gutter by a person standing on the ground. One such tool is U.S. Pat. No. U.S. 3,601,835 issued Aug. 31, 1971 to Morgan. This tool is comprised of a single, tubular, telescopic arm and the use of a rope or non-rigid wire to actuate grasping jaws. Though tubular, the arm is incapable of acting as a viaduct for water. The telescopic segments to adjust height do not incorporate water seals. Also each segment of tube has a series of spaced holes which penetrate their wall for the purpose of inserting a removable support pin or screw diminishing the structural integrity of the arm and making it pervious to water. Unfortunately this device has several shortcomings: Its inability to transport water, an important medium for dislodging as well as consolidating debris. Its complexity of design make tooling and labor costs too expensive to produce and whenever there are extensive pieces of removable hardware this lends itself to the probability that parts might come off during shipment, display or after product is purchased. Another disadvantage in the design of this invention is the rigid construction of the grasping components. There are numerous and sundry gutter sectional profiles and rigid grasping heads cannot accommodate these variances. Possibly the most significant shortcoming is the fact that this device incorporates only one arm. A person using this device must manipulate the main structure including its own weight plus the added weight of debris using only one hand since the second hand must be dedicated to manipulation of the wire or rope. This reduction in leverage becomes all the more important when trying to dislodge material that may be trapped by a tree branch or entrenched beneath a ferrule. Incorporation of a wire or rope also lends itself to a high probability of the rope becoming entangled in adjoining shrubbery or might snag on the protruding edge of a shingle or the trough itself. U.S. Pat. No. 3,743,339 issued Jul. 3, 1973 to Brackett, discloses a tool that incorporates a tubular telescopic arm and the use of a rope or non-rigid wire to actuate a sliding jaw mounted on an elongated carriage. The arm, though tubular, is incapable of acting as a viaduct for water because portions of this shaft incorporate pulleys used to guide the rope. Unfortunately this device also has several shortcomings: Its inability to transport water, an important medium for dislodging as well as consolidating debris. Its complexity of design and fabrication make tooling and labor costs exorbitant, especially considering threading a series of internal pulleys. Again it is important to point out that whenever there are extensive pieces of removable hardware this lends itself to the probability that parts might come off during shipment, display or after product is purchased. Because the actuating wire is encapsulated in the neck of this device the invention becomes nearly impossible to mend if the wire were to break. There is also disadvantage in that the rigid construction of the grasping components are not compatible with the variety of gutter sectional profiles. The actuation wire or rope can easily entangle in adjoining shrubbery or snag on sharp edges of the gutter. Again the most significant shortcoming of this device appears to be that it incorporates only one arm. A person using such a tool must manipulate and support its own weight plus the added weight of debris using only one hand since the second hand is needed to manipulate the wire or rope. This loss of leverage becomes even more significant when trying to dislodge material that is trapped by a tree branch or entrenched beneath a ferrule. U.S. Pat. No. 3,972,552 issued Aug. 3, 1976 to Earp, discloses a tool that again incorporates a tubular telescopic arm and the use of a rope or non-rigid wire to actuate a grasping jaw. The arm, though tubular, is not intended to act as a viaduct for water. Unfortunately this device also has several shortcomings: Its inability to transport water, an important medium for dislodging as well as consolidating debris. Its complexity of design and fabrication make tooling and labor costs too expensive. Again it is important to point out that whenever there are extensive pieces of removable hardware this lends itself to the probability that parts might come off during shipment, display or after product is purchased. The long, slender segments of the mechanism appear prone to damage by bending. The extended rod fingers on the grasping head will inevitably snag overhanging shingles. There is also disadvantage in that the rigid construction of the grasping components are not compatible with the variety of gutter sectional profiles. A person using such a tool must manipulate and support its own weight plus the added weight of debris using only one hand since the second hand is needed to manipulate the wire or rope. This loss of leverage becomes even more significant when trying to dislodge material that is trapped by a tree branch or entrenched beneath a ferrule. The actuation wire or rope is also prone entangle in adjoining shrubbery or snag on sharp edges of the gutter. U.S. Pat. No. 4,057,276 issued Nov. 8, 1977 to Currie discloses a tool that incorporates a single, tubular arm. The arm is extendable when a male plug on one segment inserts into a female socket on the adjoining segment where it is secured via a cotter pin. The grasping jaws are again activated by the use of a rope or non-rigid wire attached to a pair of extraordinarily large grasping jaws. The arm, though tubular, is not intended to act as a viaduct for water. Unfortunately this device also has several shortcomings: Its inability to transport water, an important medium for dislodging as well as consolidating debris. There appears to be several major flaws in this design. The large size of the grasping scoops would make operating this device very difficult. The wire/robe which draws the jaws would require an excessive downward pull and would in all probability weaken the gutter structure long before it closed upon the debris. The fact that organic debris is most often cemented together by mud and other dissolved organic materials would appear to render this invention inoperable. Again the disadvantage of rigid grasping scoops such as those shown are not compatible with the variety of gutter sectional profiles. As with the previous inventions, because this device incorporates a single arm, it therefore lacks the leverage necessary to dislodge and lift material that may be trapped by a tree branch or entrenched beneath a ferrule. The actuation wire or rope is prone to entangle in adjoining shrubbery or snag on sharp edges of the gutter. U.S. Pat. No. 4,114,938 issued Sep. 19, 1978 to Strader discloses a tool that incorporates a single, telescopic, tubular arm. The grasping jaws are paddle-shaped and again activated by the use of a rope or non-rigid wire. The arm, though tubular, is not intended to act as a viaduct for water. The shortcomings of this device are similar to the previous examples of prior art: Inability to transport water, an important medium for dislodging as well as consolidating debris. Again the disadvantage of rigid grasping scoops such as those shown are not compatible with the variety of gutter sectional profiles. As with the previous inventions, because this device incorporates a single arm, it therefore lacks the leverage necessary to dislodge and lift material that may be trapped by a tree branch or entrenched beneath a ferrule. The actuation wire or rope is prone to entangle in adjoining shrubbery or snag on sharp edges of the gutter. U.S. Pat. No. 4,310,940 issued Jan. 19, 1982 to Moore discloses a tool that incorporates a single, telescopic, tubular arm. The grasping alligator-like jaws attack the debris on a horizontal plane, but unlike the previously described patents, it incorporates a handle concentric to the arm which slides up and down driving a rod which, in turn, via a U-joint transmits the motion into raising and lowering the upper portion of the jaws. Again the arm is not intended to act as a viaduct for water, and is suggested to be solid. The shortcomings of this device are similar to the previous examples of prior art: Inability to transport water, an important medium for dislodging as well as consolidating debris. The complexity of the mechanism would make it not be cost effective. The jaws open and close vertically and by the lack of any inward curvature appear unadapted for consolidating and holding materials that may be compressed and cemented. Again the jaws shown, being rigid, are not compatible with the variety of gutter sectional profiles. As with the previous inventions, because this device incorporates a single arm, it therefore also lacks the leverage necessary to dislodge and lift material that may be trapped by a tree branch or entrenched beneath a ferrule. U.S. Pat. No. 4,930,824 issued Jun. 5, 1990 to Mathews and Ricketts discloses a tool that incorporates a single, telescopic, tubular arm with jaws activated by a wire or rope. The grasping rake-shaped jaws appear to grasp the debris on a plane vertical to the trough. Again the arm is not intended to act as a viaduct for water, and is suggested to be solid. The shortcomings of this device are the fact that they are not only limited in the breadth of the jaws, but are not designed to move the debris horizontally, therefore consolidating it. Inability to transport water, an important medium for dislodging as well as consolidating debris. The complexity of the mechanism would make it too expensive to market. Because the jaws close perpendicular to the longitudinal plane of the gutter, they appear better able to adjust to the variety of gutter sectional profiles. Unfortunately this greatly limits the quantity the jaws are able to access during each operation. As with the previous inventions, because this device incorporates a single arm, it therefore also lacks the leverage necessary to dislodge and lift material that may be trapped by a tree branch or entrenched beneath a ferrule. Also the wire or rope is prone to snagging on shrubs and other obtrusions. Accordingly, a need remains for a tool which is better adapted to the inherent problems related to the removal of compacted gutter debris. SUMMARY OF THE INVENTION It is, therefore, an object of the invention to clean a rain gutter from a remote position. Another object of the invention is to provide a cleaning tool that provides increased leverage for dislodging debris from a gutter. Another object of the invention is to provide an improved technique for dislodging and consolidating debris from a gutter. Another object of the invention is to clean gutters having a variety of cross sectional shapes. Another object of the invention is to clean gutters made from a variety of different materials. A further object of the invention is to provide a gutter cleaning tool that is inexpensive and reliable. One aspect of the present invention is a gutter cleaner comprising a first inverted J-shaped member having a scoop, a handle arm, and an apex portion, and a second inverted J-shaped member having a scoop, a handle arm, and an apex portion, the first and second J-shaped members pivotally connected near the apex portions such that the scoops pivot toward each other as the handle arms are pivoted toward each other. The gutter cleaner can include a hinge for pivotally connecting the first and second J-shaped members. Such a hinge can include a cylindrical race, and the first J-shaped member can include a cylinder-shaped journal portion so that the journal portio can be portion disposed within the race. The hinge can include a slot communicating with the race along the entire length of the race, the slot having a width less than the diameter of the journal so that the journal can be snapped into the race. The scoop of the first J-shaped member and the apex portion can be joined at approximately a 90 degree angle, and the handle arm and the apex portion can be joined at approximately a 60 degree angle. The first J-shaped member can include a passageway for transporting fluids to the scoop, and a baffle that directs fluids into the scoop. A coupling communicating with the passageway can be mounted on the handle arm, and a valve can be used to coupled a hose to the passageway. The scoops can include one or more teeth or bristles, can be ellipsoidal shaped and can be made from a pliable material. The gutter cleaner can include a handle grip attached to the handle arm of the first J-shaped member which slides along the handle arm. A mirror can be mounted near the apex of the first J-shaped member. The gutter cleaner can include an extension arm connected to the handle arm of the first J-shaped member and a pivoting joint connected to the handle arm of the second J-shaped member with another extension arm connected to the pivoting joint. Another aspect of the present invention is a method for cleaning a gutter trough including the steps of inserting a first scoop into the gutter trough; sliding the first scoop along the gutter trough to accumulate debris pivoting a second scoop toward the first scoop thereby grasping the accumulated debris with the scoops; and lifting the scoops from the gutter trough, thereby removing the debris. The method can also include the step of discharging a fluid into the first scoop. The incorporation of two arms provides several advantages over single-armed tools. One advantage is leverage. An advantage of increased leverage involves the initial entrance of the tool into organic debris which is often intertwined with twigs and branches as well as cemented together by organic adhesives. The initial function of a gutter cleaning tool is penetration and breaking up the debris. Only after the material is broken up and separated can it be removed. By incorporating a fulcrum-like hinge at the upper end of the tool the user gains significant leverage. This leverage is first translated into the necessary force required to manipulate and sever the indurated material. Increased leverage also plays an important role in pushing the severed segment along the trough, allowing it to accumulate into a compressed pile. And finally this leverage allows the two arms to swing together clamping a significant amount of material and placing the handle in parallel proximity. At this point the horizontal leverage changes to vertical leverage as the mass of debris can now be lifted from the trough using both hands mutually grasping both arms. This vertical leverage is of great importance because the debris being removed quite often hangs up on the protruding shingles on one side and the inward bend of the gutter lip on the opposite side. Ferrules also impede removal especially when twigs and branches are prevalent in the debris. Leverage is also important in transporting the material from the roof and depositing the debris in a wheelbarrow or other container. The grasping/scoop appendages at the end of the arms which dislodge and remove the debris are another improvement over the aforementioned prior art. Because they are fabricated from injection molded plastic alloy they are less likely to scratch or bind when in contact with the thin-walled gutter structure. Being of pliable plastic alloy, they will not only fail to bind or scratch the metal or vinyl gutters, but their flexibility enables them to conform to the variations in gutter profiles. The ladle shape of these scoops serve several purposes which also are improvements over prior art. Their shape causes compression of the material into an elongated ellipsoid. This makes the debris less likely to snag on obstacles as it is lifted from the trough. The scoop incorporates a baffle which is designed to direct water passing through the arm to exit the scoop along its inside surface. This surface being curved tends to direct the water beneath the material. This not only helps to dislodge debris which may be adhering to the wall, but it also tends to move and consolidate finer materials such as pine needles and shingle sand. None of the aforementioned inventions takes into consideration removal of this finer debris. The final advantage of this invention's scoops is that they are unibodied articles, employing no hardware or pre-assembled parts. Therefore the cost of these appendages is far less than those shown in prior art. The hinge incorporated near the upper end is also made of plastic alloy. It is made from a more rigid alloy to maintain greater rigidity at the fulcrum point. Depending on configuration, the hinge may be attached during or after the tubing is bent. The hinge incorporates other advantages such as a means for easily detaching both component parts. This allows advantages in both efficiency of packaging and storage as well as enabling a person to detach and use only one of the arms to purge the system of debris too small to pick up with the scoops. The handle grips are another improvement over prior art. Made of a supple, plastic alloy such as low density, polypropylene, they offer a firmer hold on the arms. They are designed with enough flexibility to allow them to be slipped up or down the arms so as to adjust to the comfort of the user. On the lower end of each arm a brass, female garden hose coupling is press fitted. This allows attachment of a hose to either end thus adapting to either right or left handed use. A single removable on/off ball valve is screwed into one of the female couplings. Having male threads on one end and female on the opposite, it can be installed in series with the hose and can also be attached to either arm. The arms used in this invention incorporate two bends made on or about the same lateral plane. The bend closest to the upper end would be 90 degrees and the second bend about 60 degrees. The spacing of these two bends is an important feature of the invention. Because the two ladle scoops need to remain in mirror image alignment, the bends are separated by the width of the hinge. In so doing the shafts cannot move forward or backwards relative to each other and no mechanical attachment need be required to prevent such movement. Extension arms can be easily added if necessary to access higher than normal gutters. These extensions could be of varying length and would incorporate a male hose coupling on the top end and a female coupling on the lower end. One extension would be constructed as a single uninterrupted segment of tubing. The second arm would incorporate a u-joint hinge. When using the extension a person pushes the arm with the u-joint hinge upwards vertically. The u-joint coupling transfers this upward force outward causing the upper arm to swing outward thus causing the scoops to close and grasp the debris. The foregoing and other objects, features and advantages of the invention will become more readily apparent from the following detailed description of a preferred embodiment of the invention which proceeds with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an embodiment of a gutter cleaner in accordance with the present invention. FIG. 2 is a perspective view showing a portion of the gutter cleaner of FIG. 1 with portions cut away to show more detail. FIG. 3 is a perspective view of an embodiment of a scoop of the gutter cleaner of FIG. 1 in accordance with the present invention with portions cut away to show more detail. FIG. 4 is a perspective view of an embodiment of a scoop of the gutter cleaner of FIG. 1 in accordance with the present invention. FIG. 5 is a perspective view of an embodiment of a scoop of the gutter cleaner of FIG. 1 in accordance with the present invention. FIG. 6 is a perspective view of an embodiment of a hinge in accordance with the present invention. FIG. 7 is a perspective view of an embodiment of a hinge in accordance with the present invention. FIG. 8 is a perspective view of an the gutter cleaner of FIG. 1 showing optional extension arms. FIG. 9 is a perspective view of an embodiment of a pivot joint in accordance with the present invention. FIG. 10 is a perspective view of an embodiment of a pivot joint in accordance with the present invention. FIG. 11 is a perspective view of the gutter cleaner of FIG. 1 showing more operational detail. FIG. 12 is a perspective view showing an operator manipulating the gutter cleaner of FIG. 1. DETAILED DESCRIPTION Indicated generally at 10 in FIG. 1 is an embodiment of a gutter cleaner in accordance with the present invention. Prior to describing the detailed structure of the invention, the key components will be identified followed by a brief description of the operation of the system. Then a more detailed description of each of the components will be provided along with a more detailed description of the operation. A right inverted J-shaped member 12A includes a handle arm 14A, a scoop 16A and an apex portion 18A. A left inverted J-shaped member 12B includes a handle arm 14B, a scoop 16B and an apex portion 18B. J-shaped members 12A and 12B are pivotally joined near their respective apex portions by a hinge 20. The gutter cleaner 10 can be operated in wither a left-hand mode or a right-hand mode. In the right hand mode of operation, the J-shaped members 12A and 12B are first pivoted apart to place the cleaner 10 in an open configuration as shown in FIG. 1. The right hand scoop 16A is inserted into the trough 22 of rain gutter 24. The entire cleaner 10 is then moved to the left as shown by arrow 26, thereby dislodging and consolidating debris in front of scoop 16A. The handle arm 14B of left J-shaped member 12B is then pivoted toward the handle arm 14A of right J-shaped member 12A as shown by arrow 28, thereby causing the consolidated debris to be grasped between scoops 16A, 16B. The entire cleaner 10 is then lifted vertically, thereby removing the debris from the gutter. Handle grips 30A and 30B are mounted on handle arms 14A and 14B, respectively, to improve leverage and comfort. Handle grips 30A and 30B slide along the handle arms as shown by arrows 32A and 32B to adjust for the operator's height. J-shaped members 12A and 12B include couplings 34A and 34B mounted to the respective ends of handle arms 14A and 14B. In the right-hand mode of operation, coupling 34A connects a hose 36 to an internal passageway (not shown) in right J-shaped member 12A, preferably through shut off valve 38. The internal passage connects the coupling to scoop 16A. In operation, pressurized water or other cleaning fluid from hose 36 is channeled through the valve, coupling, and internal passage to scoop 16A. The fluid is directed into the scoop by a baffle (not shown) to assist in dislodging and consolidating debris. Left J-shaped member 12B has a similar fluid passage structure and operation. More detailed consideration will now be given to the structure of the gutter cleaner 10 of the present invention. Referring to FIG. 2, right inverted J-shaped member 12A includes a scoop arm 42A and a journal portion 48A, both of which are straight cylindrical tubes. Scoop arm 42A is joined to a first end of journal portion 48A at approximately a 90 degree angle by a first tubular elbow 44A. The axis of journal 48 is generally held in a horizontal orientation when the gutter cleaner 10 is in operation. Thus, the axis of scoop arm 16A is generally oriented in a vertical direction. J-shaped member 12A also includes a straight cylindrical handle arm 14A which is joined to the second end of journal portion 48A at approximately a 60 degree angle by a second tubular elbow 46A. The scoop arm, first elbow, journal portion, second elbow, and handle arm are joined such that they all lie in approximately the same plane and form a rigid tube 40A which is generally J-shaped. Rigid tube 40A has an internal passageway 54 which runs the entire length of the tube, and the tube is essentially liquid tight along its entire length except for circular orifices 56 and 58 at either end. Rigid tube 40A is preferably made from a single piece of cylindrical aluminum alloy tubing type 6061-T6 or equivalent, has an outside diameter of 0.75 inches, a wall thickness of 0.05 inches, and a total length of approximately 50 inches. The scoop arm 42A, and journal portion 48A are each approximately 3 inches long. The first and second elbows 44A and 46A have a bend radius of approximately 3 inches. Rigid tube 40A is formed by leaving a 3 inch straight length at one end for scoop arm 42, then bending the tubing at approximately a 3 inch radius to form a first elbow 44 having curvature of approximately 90 degrees. Another straight section is left for journal portion 48, and then the tubing is bent at a 3 inch radius again to form second elbow 46 which has a curvature of approximately 60 degrees and is substantially coplanar with the first elbow. The remaining straight section forms the handle arm 14A. The length of journal section 48 is determined by the distance between elbows 44 and 46 and is preferably approximately equal to the length of hinge 20. If hinge 20 does not have an opening for assembling the hinge to the journal 48 of the J-shaped member, then the hinge must be assembled to the journal before the second bend is made. First J-shaped member 12A includes a ladle-shaped scoop 16A having a generally planar rim 64A that is generally elliptical shaped with the main axis of the ellipse oriented in a generally vertical direction. The scoop 16A has an ellipsoidal shaped inner surface 17A. Scoop 16A also includes a cylindrical tubular coupling 60A at the top end which protrudes from the scoop such that the axis of the coupling 60A is substantially aligned with the plane of rim 64A. The scoop also includes one or more teeth 62A mounted at the bottom end of the scoop near the rim and protruding normally from the plane of the rim. The scoop 16A is attached to the rigid tube 40A by sliding the coupling 60A over the free end of scoop arm 42A, thereby forming a substantially fluid-tight seal between the passageway of the rigid tube and the scoop. The coupling can have either a slip-fit or an interference-fit on the rigid tube. Scoop 16A also includes a baffle 66A located at the lower end of coupling 60A for projecting pressurized fluids flowing through the passage 54A into the curved inner surface of the scoop. The baffle 66A is not visible in FIG. 2, but it is visible in the scoop shown in FIG. 3. FIG. 3 shows an alternative embodiment of scoop 16A having openings 78 to allow fluid to drain from the scoop. The location and design of baffle 66A is substantially the same for the scoop shown in FIG. 2. The baffle may be straight or semi-circular in shape. The scoop is preferably made from a pliable or semi-liable plastic such as polypropylene alloy. FIG. 4 shows another alternative embodiment of scoop 16A. This embodiment includes straight sidewalls 65 and a baffle 66. FIG. 5 shows another alternative embodiment of scoop 16A. This embodiment includes a row of bristles 80 mounted along the bottom of the rim of the scoop. Referring again to FIG. 2, J-shaped member 12A includes a threaded hose coupling 34A attached to the free end of handle arm 14A. The coupling includes a barbed connector 68A that is disposed within rigid tube 40A and provides a substantially liquid-tight seal between the coupling 34A and the tube 40A. The coupling is preferably made from brass or other rigid, corrosion resistant material and has female pipe threads suitable for connection to a common garden hose. The barbed connector 68 A of the coupling is preferably press-fit into rigid tube 40A. J-shaped member 12A also includes a tubular handle grip 30A that is slip-fit on handle arm 14A such that the grip can be slid up and down on the arm. Handle grip 30A is preferably made from a supple plastic alloy such as low density polypropylene. Left J-shaped member 12B is substantially identical to member 12A and has all of the same components, the only difference being the orientation of the scoop 16B which is mounted so that the rim of scoop 16B faces the rim of scoop 16A when the two J-shaped members are assembled with hinge 20 as shown in FIG. 1. Referring again to FIG. 2, an embodiment of hinge 20 is shown at 52. Hinge 52 includes two substantially parallel races 74 and 76. The hinge also includes two slots 70 and 72 which communicate with the races for the entire length of the races. The slots have a width such that, if the hinge is made from a semi-pliable plastic alloy, journal 48A can be snapped into race 76. Likewise, the journal on the left J-shaped member 12B can be snapped into race 74. The length of races 74 and 76 is selected to be close to the length of the journals on the J-shaped members so that the hinge is held captive between the elbows of the J-shaped members thereby preventing the J-shaped members from moving laterally relative to the hinge and each other as shown by arrow 50. Hinge 52 is preferably manufactured from injection molded plastic alloy. Referring to FIG. 1, right J-shaped member 12A and left J-shaped member 12B are pivotally joined by hinge 20 to allow latitudinal rotation of member 12A relative to member 12B such that the scoops 16A and 16B pivot toward each other as the handle arms 14A and 14B are pivoted toward each other. FIG. 6 shows an alternative embodiment of a hinge generally at 96. This embodiment includes a first cylindrical sleeve 82 having two hinge lobes 88 and 90 protruding form the side of the sleeve. Hinge 96 also includes a second cylindrical sleeve 84 having a single lobe 92 protruding from the side of the sleeve 84. The two sleeves can be pivotally joined by a removable pin 86 which can be inserted into a hole 94 which runs through all hinge lobes 88, 90, 92. FIG. 7 shows another alternative embodiments of hinge 20. This hinge is similar to the hinge of FIG. 6, but the pin is captive within the hinge lobes. Referring to FIG. 1, a common garden hose 36 can be connected to either the right or left coupling 34A,B either directly, or through valve 38. Referring to FIG. 2, valve 38 is a commercially available ball valve having a male hose thread coupling 35 at one end and a female hose thread coupling 37 at the other. The valve ball is actuated by knob 39. Referring now to FIG. 8, the gutter cleaner 10 of the present invention is shown with a first extension arm 100A and a second extension arm 100B configured for right-hand operation. First extension arm 100A includes a hollow tubular shaft 101A having a passageway for transporting liquids. Extension arm 100A also includes a coupling 104A having a male thread attached to one end of extension arm 100A and a coupling 106A having a female thread attached to the other end. Couplings 104A and 106A are connected by the internal passageway running the length of shaft 101A. Extension arms 100A,B have handle grips 102A and 102B similar to those on handle arms 14A and 14B of J-shaped members 12A and 12B. The first extension arm 100A is connected to the right handle arm 14A by threading the mail coupling 104A into female coupling 34A, thereby providing a liquid-tight seal between the extension arm and the handle arm. Second extension arm 100B includes a shaft 101A which may be hollow or solid. Second extension arm 100B is connected to left handle arm 14B by a pivoting joint 108. Referring to FIG. 9, pivoting joint 108 includes a lower pivot member 110, an upper pivot member 112 and a pivot pin 114. Lower pivot member 110 is attached to the upper end of shaft 101B and is pivotally attached to upper pivot member 112 with pivot pin 114. Upper pivot member 112 includes a threaded portion 116 which is threaded into coupling 34B of left handle arm 14B, thereby pivotally connecting handle arm 14B and extension arm 100B. FIG. 10 shows an alternative embodiment of pivoting joint 108. In this embodiment, the upper pivot member 113 is L-shaped and includes slot 115 for receiving lower pivot member 110. The pivot pin 114 is offset from the center line of the pivoting joint such that, when the axes handle arm 14B and extension arm 101B are aligned along a single line, the joint can only pivot in one direction. Referring again to FIG. 8, garden hose 36 is connected to coupling 106A of first extension arm 100A through valve 38. Alternatively, gutter cleaner 10 can be configured for left-hand operation. In left-hand mode, first extension arm 100A is connected to left handle arm 14B, and second extension arm 100B is connected to right handle arm 14A. Garden hose 36 is then connected to coupling 106A through valve 38. A mirror (not shown) can optionally be attached mechanically to either J-shaped members 12A or 12B. Such attachment may involve a separate component part attached directly to either member or could be integral to an appendage on hinge 20. More detailed consideration will now be given to the operation of the gutter cleaner 10 with reference to FIGS. 1, 8 and 11. The operation will be described for the right-hand mode of operation. The operation in the left-hand mode is essentially the same, but with all steps performed in mirror image orientation. Referring to FIG. 1, garden hose 30 is first connected to coupling 34A through valve 38. Referring to FIG. 11, using handle grips 30A and 30B, left J-shaped member 12B is pivoted away from right J-shaped member 12A such that the gutter cleaner 10 placed in an open position with handle arms 14A and 14B rotated at approximately a 60 degree angle. The entire cleaner is lifted over the front lip 23 of gutter 22 and then lowered such that scoop 16A contacts the bottom of trough 24 and the right inverted J-shaped member 12A is generally in a horizontal plane that is oriented substantially normal to the axis of gutter 22. Depending on the level of induration of leaves and other debris 124 present in the gutter, it may be necessary to use the leverage provided by handle arms 14A,B to force the scoop into the bottom of the trough. The gutter cleaner can be operated with or without a water supply. If water is used, the valve 38 is opened and pressurized water flows through rigid tube 40A. The water 120 is directed by the baffle into the curved inner surface of scoop 16A. The water then flows out of the scoop and under leaves and other debris 124 as shown by arrows 122, thereby dislodging and moving the debris along the trough 24. The ellipsoidal shape of the scoops helps direct the water under the debris. The entire gutter cleaner 10 is next slid along the gutter to the left as shown by arrow 26 while maintaining the right J-shaped member 12A in the vertical plane, thereby accumulating debris in front of scoop 16A. The handle arms 14A and 14B provide leverage for sliding the debris, especially if handle arm 14B is used to pull the entire gutter cleaner along the gutter. Because the injection molded plastic scoops are somewhat pliable, they conform to the cross sectional shape of the gutter trough for better scraping action. If the embodiment of the scoop with the bristles shown in FIG. 5 is used, the bristles sweep debris from the bottom of the trough. Once a suitable amount of debris has accumulated in front of scoop 16A, handle arm 14B is then rotated back towards handle arm 14A as shown by arrow 28 in FIG. 11. This causes scoops 16A and 16B to pivot toward each other, thereby grasping the accumulated debris between them. Handle arms 14A and 14B and hinge 20 provide fulcrum-like leverage for securely grasping the debris. The entire gutter cleaner is next lifted vertically to extract the debris from the trough. The ellipsoidal shape of the scoops makes the scoops less likely to snag on obstacles as they are lifted from the trough. If one of the alternative embodiments of the scoops shown in FIGS. 3 and 4 is used, the cleaner can be held above the trough momentarily as water drains through the holes 78 in the scoop. The use of both handle arms 14A,B provides additional leverage when lifting the cleaner. The cleaner is then moved away from the gutter and the debris emptied into a suitable receptacle. If debris in the gutter is particularly indurated or cemented together by organic adhesives, the tooth like projections 62 A of the scoop shown in FIG. 2 will help the scoop penetrate into the debris. Having described and illustrated the principles of the invention in a preferred embodiment thereof, it should be apparent that the invention can be modified in arrangement and detail without departing from such principles. For example, rigid tube 40A need not have a circular cross sectional shape along its entire length, but it could have any suitable cross sectional shape as long as the journal portion is cylindrical. Similarly, the fluid used need not be water, but could be an suitable cleaning fluid under pressure. I claim all modifications and variation coming within the spirit and scope of the following claims.

An apparatus and method for cleaning overhead gutters. The apparatus includes two inverted J-shaped members connected by a hinge at the apex. Each J-shaped member has a scoop depending downwardly from the apex and a handle arm depending downwardly from the apex, the handle arm being longer than the scoop. The J-shaped members are hinged such that rotating the handle arms toward each other causes the scoops to rotate toward each other thereby grasping debris therebetween. The scoops are pliable and ellipsoidal shaped and can have teeth or bristles. The hinge provides fulcrum type leverage for grasping and dislodging debris. The J-shaped members can be snapped into and out of the hinge. The gutter cleaner includes a coupling for connecting the cleaner to a garden hose through a valve. Water is channeled to a scoop where a baffle directs the water into the scoop and under debris to dislodge and consolidate debris. The handle arms include slidable hand grips, and extension arms can be connected to the handle arms. A pivot joint can be connected between a handle arm and an extension arm. A mirror can be mounted near the apex of the gutter cleaner. The method includes rotating the handle arms and scoops apart, discharging water into the scoops, sliding the gutter cleaner along the gutter to dislodge and accumulate debris in front of a scoop, rotating the scoops together to grasp the accumulated debris, and lifting the debris from the gutter.

RELATED APPLICATIONS Applicant claims the benefit of provisional application Ser. No. 61/402,288, filed Aug. 27, 2010. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to swimming pool covers, as they relate to raised wall shaped pools which have straight and arcuate walls which extend above the coping and deck of the pool which establish gaps in the pool cover coverage and in particular to a complimentary gap eliminating device cooperable with the swimming pool cover to insure complete coverage of the pool. 2. Description of the Prior Art Covers for swimming pools are frequently used in climates where the pool is not used for certain periods of the year due to inclement weather. The pool cover is designed to be stretched across the pool and secured so as to prevent the ingress of dirt, waste material, or debris, such as fallen leaves during the off season. The cover also serves as a safety factor when the pool is not in use. The swimming pool cover is typically a flexible, waterproof substrate or sheet of material, either impervious or fine mesh having a plurality of resilient, biased tie down straps secured about its periphery, the tie down straps being secured to a plurality of anchor bolts fixedly secured in the surrounding pool apron or deck, the resilient biased tie down straps being adjusted to achieve the desired tautness of the cover. In such a configuration, the pool cover covers the pool and the periphery of the surrounding deck or apron in an overlapping fashion, thus preventing ingress of debris into the pool during the off season. Pool covers of the type described are easily installed on pools having a geometric shape, such as a rectangle, or an L-shape. They are also easily installed and effective with respect to pools, such as kidney-shaped pools and other pools having arcuate peripheries. In effect, covers of the type described are effective with respect to all pools in which the surrounding apron, deck or periphery is at one level or height. A problem develops with respect to any shape pool which incorporates side walls of uneven height. The simplest example is a freeform pool which incorporates a waterfall, which waterfall flows over and into the pool from a rock wall or concave wall, the height of which is greater than that of the peripheral apron or decking of the pool. Another example would be a freeform pool which incorporates a spa adjacent to the pool having a side wall higher than the peripheral apron or decking of the pool, and sharing a convex wall with the pool which may be of a different radius. In these instances, it is difficult to design a pool cover which will abut the curvatures of these walls having a height greater than that of the apron or decking of the pool. Designs have been developed to secure a cover in as close approximation to these arcuate surfaces as possible, but in most cases there still remains a gap which allows for the ingress of dirt, leaves, and debris during the off season. This gap may further increase if the pool cover is subjected to loads such as snow or accumulated standing water. Still further, the gap varies as the pool cover installer adjusts the tension of the securing straps. Still further, this gap presents a safety problem due to its size, such that the possibility exists that a small pet or rodents could fall through this gap and into the underlying water. Attempts have been made to provide a closure for the gap existing between the pool cover and the arcuate side wall. One such solution included the fastening of an additional waterproof flap to the end of the pool cover adjacent the arcuate wall and providing some weight and volume to this flap so that it would lie across the gap. This flap is commonly referred to in the trade as a bumper. The bumper is essentially an extension of the pool cover in that it is clipped or sewn to the edge of the cover. A sewn bumper proves difficult to fabricate and also to fold for storage when not in use. This has proved to be ineffective in that atmospheric conditions cause the clipped flap to disengage, pull away from the underlying pool cover or the wall, and fail to provide adequate and continued closure to the gap. Applicant has developed an improved pool cover gap system which effectively closes the gap formed between a swimming pool cover and an arcuate or straight wall surface of greater height than the peripheral apron or decking about the pool, which is easily installed and provides an effective barrier to the passage and ingress of debris into the underlying water of the pool, and also closes the gap from a safety standpoint as it might relate to small pets or rodents. OBJECTS OF THE INVENTION An object of the present invention is to provide for a novel swimming pool cover gap system which secures the gap between a swimming pool cover and a wall of greater height than the peripheral apron or decking about the pool. It is another object of the present invention to provide for a novel swimming pool cover system which secures to the elevated wall of the pool and overlaps the swimming pool cover above and below the cover, thereby sealing the gap between the swimming pool cover and an elevated straight or arcuate wall of the pool. Another object of the present invention is to provide for a novel swimming pool cover gap system which includes a gap eliminator bumper which closes the gap between a swimming pool cover and an elevated straight or arcuate wall portion of the pool which provides for greater safety when the pool is closed. It is a still further object of the present invention to provide for a novel swimming pool cover gap system which includes a gap eliminating bumper which maintains closure of the pool even when the swimming pool cover experiences a water load or a snow load which causes the pool cover to stretch. It is a still further object of the present invention to provide for a novel swimming pool cover system which provides for a gap eliminator bumper which is compact and easily stored when not in use. SUMMARY OF THE INVENTION An improved swimming pool cover system which incorporates a gap eliminator for use on pools which have walls of varying height and curvature, the gap eliminator secured to the wall by a plurality of cable guides securing a support cable, the gap eliminator having a sleeve including a weighted buoyant material disposed below the pool cover attached to the cable and a second sleeve having weighted buoyant material disposed above the pool cover attached to the cable, thereby sealing the gap between the pool cover and the wall, the gap eliminator having an optional third sleeve adjacent the second sleeve having a weighed non-buoyant material disposed therein. BRIEF DESCRIPTION OF THE DRAWINGS These and other objects of the present invention will become apparent, particularly when taken in light of the following illustrations wherein: FIG. 1 is a top view of a conventional pool cover of the prior art illustrating the manner of its installation; FIG. 2 is a side view of the tie down straps utilized in conjunction with the pool cover of FIG. 1 ; FIG. 3 is a perspective view of a free form pool which incorporates a waterfall and a spa which present a concave spatial surface and a convex spatial surface respectively, which extends above the decking or apron of the pool; FIG. 4 is a front perspective view of the concave waterfall section illustrating the manner in which the prior art has attempted to extend a pool cover into this spatial area; FIG. 5 is a perspective view of an arcuate, raised spa wall section illustrating the prior art solution to a convex wall problem; FIG. 6 is a perspective view of Applicant's gap eliminator; FIG. 7 is an end cross sectional view of the gap eliminator of FIG. 6 ; FIG. 8 is a perspective view of the second embodiment of the gap eliminator as illustrated in FIG. 6 ; FIG. 9 is a top view of a cable installation for use with a concave waterfall area of a pool; FIG. 10 is a side cross sectional view of the gap eliminator of FIG. 6 installed in conjunction with a pool cover and the cable assembly of FIG. 9 ; FIG. 11 is a side cross sectional view of a gap eliminator of the embodiment illustrated in FIG. 8 installed in conjunction with a pool cover and the cable assembly of FIG. 9 ; FIG. 12 is a perspective partial cutaway view of the installed gap eliminator of FIG. 6 , along an elevated, straight wall; FIG. 13 is a perspective partial cutaway view of the second embodiment of the gap eliminator of FIG. 8 installed against an elevated straight wall; FIG. 14 is a cross-section of a gap eliminator of the present invention incorporating a unitary cable sleeve; and FIG. 15 is a perspective view of a gap eliminator of the present invention which is longitudinally arcuate to custom fit and abut an arcuate elevated wall of a pool. DETAILED DESCRIPTION OF THE INVENTION FIGS. 1 through 5 illustrate the state of the prior art in addressing the problem heretofore set forth. FIG. 1 is a top view of a conventional pool cover installed over a pool to prevent the ingress of particulate matter and debris during the season when the pool is not in use. FIG. 2 is a partial side view of a tie down strap associated with the pool cover of FIG. 1 . The pool 10 illustrated in FIGS. 1 and 2 are generally rectangular in nature having an edging or coping 12 about its periphery 14 , there extending outwardly from the coping a pool apron or decking 16 comprised of concrete, decorative stone, wood, or the like. The decking or apron 16 is substantially level with the coping or edging 12 of pool 10 . A pool of this type could be any shape as long as the coping and deck were on the same level. The cover 18 would be secured over the pool by securing a plurality of tie down straps 20 to a plurality of anchor bolts 22 which are secured in the apron or decking 16 . The anchor bolts 22 are fitted into a recess cylinder housing 24 which is set in the decking or concrete apron 16 which allows the anchor bolt 22 to be recessed in its cylinder housing 24 during the pool season, but to be raised above the level of the apron or decking 16 so as to be engaged by a ring hook or spring assembly 26 on a particular tie down strap 20 . The cover 18 is unrolled across the pool with consecutive tie down straps 20 being engaged with selective anchor bolts 22 arranged about the pool. The tie down straps 20 themselves consist of adjustable cloth straps oftentimes incorporating a resilient strap in combination with a biasing spring means so as to the allow the installer to engage the tie down strap with the anchor bolt and then adjust the tie down straps to affect the desired tautness of the pool cover. It should be noted that this design of pool cover and tie down straps is identical to the type of pool cover and tie down straps that would be utilized with the gap eliminator of the present invention. The problem with a free form pool is that it often contains elevated arcuate and straight wall portions which extend above the standard apron or decking level thereby presenting problems peculiar to the particular design and installation of the pool cover in order to provide cover and protection in these defined elevated areas. FIG. 3 is a perspective view of a free form pool having many of the same elements as the pool illustrated in FIGS. 1 and 2 , including coping 12 , and apron or decking 16 about its periphery 14 , however, the standard or common level of the apron or decking is interrupted by several raised walls. The owner has incorporated a hot tub/spa 40 in conjunction with the free form pool, the hot tub/spa 40 having a convex arcuate surface 42 extending into the pool area, and also extending above the apron or decking. The owner has also incorporated a waterfall 44 defined by a concave arcuate surface 46 also extending above the level of the apron or decking 16 and a waterfall 45 having a straight elevated surface 47 . In these situations, the level of the apron or decking has been interrupted by the elevated walls of the hot tub/spa 40 and waterfalls 44 and 45 , thereby denying the ability to position anchor bolts at a common level. The convex elevated wall of the spa hot tub 40 that projects into the pool area has been addressed by the use of the anchor bolts 22 A and 22 B (not shown) on either side of the hot tub spa 40 (See FIG. 5 ). These anchor bolts are utilized not only to engage the tie down straps of the pool cover, but are also utilized to stretch a taut cable 48 about the protruding circumference 42 of the hot tub/spa 40 that projects into the pool area. The pool cover is fabricated with clips or ties 49 on this portion of the pool cover which allow the installers to engage these clips or ties 49 on the taut cable 48 . The taut cable 48 drawn about this portion of the hot tub spa 40 is level with the coping 12 and the deck or apron 16 . However, in adjusting the tautness of the tie down straps 20 about the periphery of the pool by the installer, taut cable 48 will oftentimes be pulled away from the convex periphery 42 of the spa. The concave nature 46 of the elevated waterfall surface is addressed in the same manner (See FIG. 4 ) and suffers from the same drawbacks enumerated previously. FIG. 6 is a perspective view of a first embodiment of Applicant's gap eliminator, and FIG. 7 is an end cross-sectional view of the gap eliminator illustrated in FIG. 6 . Gap eliminator 100 is generally longitudinal in shape preferably being formed from a sheet of resilient pliable waterproof material which when folded in half and sewn or heat sealed on a longitudinal axis, presents the following structure. When positioned in a planar orientation gap eliminator 100 has an upper surface 102 , having lateral edges 104 and 106 , and lower surface 107 . The resilient pliable fabric is joined as a result of sewing or heat sealing so as to form a plurality of longitudinal sleeves. First sleeve 110 defines an interior channel along lateral edge 104 . A second sleeve 112 extends along lateral edge 106 separated from first sleeve by a web portion 120 . First sleeve 110 has a larger diameter than second sleeve 112 . The gap eliminator 100 may be closed at end 108 and access to first and second sleeves 110 and 112 is by means of a zipper type access 114 at second end 116 or both ends may have a zipper type access. First sleeve 110 and second sleeve 112 are designed to receive and accommodate weighted, but buoyant material, such as a polyethylene, polystyrene, or styrofoam rods 118 dimensioned to be slidably receivable within the respective sleeves. First sleeve 110 is designed to receive a single rod preferably of greater diameter and second sleeve 112 is designed to receive at least two rods preferably of smaller diameter. A detailed description of the installation of the gap eliminator 100 will follow, but to appreciate the structural design of gap eliminator 100 , reference is now made to FIG. 10 which is a cross-sectional view of the installation of the gap eliminator 100 to a pool which includes a raised wall 44 which may be straight or arcuate, such as a waterfall or the like, which is above the coping 12 and deck or apron of the pool, and thus prevents the pool cover 18 from being drawn a distance across the edge of the coping 12 before being secured to the deck or apron as heretofore discussed. The gap eliminator 100 cooperates with the installation of a plurality of cable guides 128 which are spaced apart across the face of the vertical wall 44 and embedded therein to secure a cable 130 in close fitting relationship with the face of the wall 44 . The pool cover 18 will be clipped on to cable 130 . However, the gap eliminator 100 is installed when the cable guides 128 are installed into the face of the wall. Slight apertures are cut along the longitudinal web portion 120 between first and second sleeves 110 and 112 so that the web portion 120 can be secured and abut the face of the wall 44 when the cable guides 128 and washer 129 are installed. The cable 130 is then secured to cable guide 128 . The cover 18 is then installed to the cable 130 with second sleeve 112 containing two of the weighted buoyant rods 118 positioned on the top of the pool cover while the first sleeve 110 containing the larger diameter weighted yet buoyant rod 118 is positioned on the underside of cover 18 , thus insuring closure of any gap which may exist between the cable securing the pool cover and the wall of the raised wall surface. FIG. 8 is an end cross-sectional view of a second embodiment of the gap eliminator 100 and FIG. 11 is a cross-sectional view of the second embodiment of the gap eliminator installed. The second embodiment of the gap eliminator is identical to the first embodiment with the exception of the addition of a third sleeve 140 formed adjacent the second sleeve 112 . Access to this third sleeve is identical to that of the first embodiment by means of zippered end. Third sleeve 140 is designed for those climate areas which might encounter severe winter conditions. In such conditions, the weighted, yet buoyant polystyrene, polyethylene or styrofoam rods 118 originally positioned within second sleeve 112 may need some additional weight. Third sleeve 140 is designed to accommodate a weighted non-buoyant rod 142 of greater density than those previously discussed or third sleeve 140 could be filled with a weighted substance, such as sand or the like, positioned in a sealable container or containers and slidably positioned within sleeve 140 , which could be easily installed in third sleeve 140 and easily removed and discarded when the pool cover is removed for the season. FIG. 11 illustrates that this second embodiment of the gap eliminator is installed in the same manner as the first embodiment. FIG. 9 illustrates the installation of the cable guides 128 utilized to secure cable 130 about the face of a concave arcuate wall such as a water fall for the installation of the gap eliminator 100 . The cable guides 128 are installed in spaced apart relationship and the gap eliminator 100 would be simultaneously positioned with the cable guides before securing cable 130 to the cable guides. FIG. 9 also illustrates the gap problem associated with an arcuate raised wall. The spacing of the cable guides 128 as illustrated in FIG. 9 increases from end A to end B. The closer the spacing the smaller the gap C, thus the area of the gap increases from end A to end B as a result of the increase spacing. It is this gap which existed in the prior art which the Applicant has addressed with respect to the gap eliminator. Regardless of the spacing of the cable guides, the gap eliminator, being secured to the cable guides 128 , will cover and eliminate the gap C. The actual spacing of the cable guides 128 will be dictated by the length of the wall, the curvature of the wall, and the aesthetics desired by the owner of the pool. The web portion 120 between first and second sleeves 110 and 112 can have a plurality of small slits formed by the installer to allow the installer to pass the cable guide 128 through the slit and into a threaded bore formed in the face of the arcuate wall. A washer 129 (see FIG. 7 ) sandwiches the web portion 120 between washer 129 and the wall. In this manner, the installer, in the field, can insure that the plurality of slits required will coincide with the location of a cable guide 128 in order to provide for a snug fit. It will also be recognized by those with skill in the art, that the radius of the ark of the raised wall may vary. Therefore the gap eliminator may have a continuous rod installed in its sleeves 110 and 112 for the entire length of the gap eliminator 100 , or there may be a plurality of rods spaced end to end, of a shorter length in order to accommodate and allow for the gap eliminator 100 to become more arcuate to accommodate a wall of greater curvature. Still further, it will be recognized that depending upon the length of the wall and its concavity, it is possible that more than one gap eliminator would need to be installed end to end in order to span the distance of the walls concavity. In such instances the ends of the gap eliminators 100 may be formed with grommets 101 for receipt of tie downs 103 securing adjacent gap eliminators 100 (See FIG. 6 ). FIGS. 12 and 13 are perspective partial cutaway views illustrating the installation of the first and second embodiments of the gap eliminator 100 and pool cover adjacent an elevated straight wall 170 of a pool which is not concave nor convex. Modern architectural designs of pools oftentimes include multi-levels about the pool surface such that the pool coping and the apron or deck are not all on the same level. Applicant's gap eliminator 100 can also accommodate these designs in the same manner as described with respect to convex or concave raised walls. The reference numbers in FIGS. 12 and 13 and the structural elements to which they refer are identical as previously discussed with FIG. 10 illustrating the installation of the first embodiment of the gap eliminator 100 and FIG. 11 illustrating the second embodiment of the gap eliminator 100 with the additional third sleeve 140 and added weight component. In those rare instances where cable guides 128 cannot be affixed to the wall be it concave or convex, a modified gap eliminator would be fabricated with a cable sleeve 150 formed longitudinally in the web 120 of the gap eliminator. Cable sleeve 150 would extend the length of the gap eliminator and would be in alignment with the web portion 120 between first and second sleeves 110 and 112 on the lower surface of the gap eliminator. This modification is illustrated in FIG. 14 which is a cross-sectional view of this modification. It does not lend itself to the optimum solution, but will close a gap. The cable sleeve may receive a standard cable or to better close a gap, a cable made of deformable material which would adapt to the desired curvature could be extended through the cable sleeve 150 and then adapted to the curvature by the installers which would further eliminate any gap. The embodiments of the gap eliminator heretofore described are longitudinally straight in their fabrication and shape. The rods utilized for insertion into first sleeves 110 and second sleeves 112 , constructed of polyethylene, polystyrene or styrofoam, are also somewhat flexible or alternatively they are segmented to allow for the generally longitudinal straight gap eliminator to be formed into an arcuate shape to match the arcuate shape of the elevated wall of the pool. The gap eliminator, however, may also be fabricated in an arcuate shape to either custom fit a particular arcuate wall of a pool, or it could be fabricated in an arcuate shape, the arch having a particular radius to accommodate what are standardized radii of arcuate elevated walls associated with pools and spas. FIG. 15 is a perspective view illustrating a particular arcuate gap eliminator 100 constructed in the same manner as the embodiments illustrated in FIGS. 6 and 8 with the exception that the lateral edges 204 and 206 are arcuate. The sleeve construction and the closure means would be identical to those previously illustrated. The gap eliminator illustrated in FIG. 15 would utilize the resilient, flexible type of polyethylene, polystyrene or Styrofoam rods 118 as used and illustrated with respect to FIGS. 6 and 8 . In the embodiment illustrated in FIG. 15 , the rods 118 would be resilient and flexible to accommodate the curvature of the sleeves 110 and 112 or the rods could be segmented to further cooperate with the curvature of the gap eliminator 100 illustrated in FIG. 15 . Third sleeve 140 having a weighted container slidably secured therein, the weighted container not having the flexibility of the rods in sleeves 110 and 112 would require a plurality of weights to be slidably inserted in order to accommodate the curvature of the gap eliminator. It will be recognized by those of ordinary skill in the art that the gap eliminator described heretofore can be made in any convenient length. Consideration must be had for the fact that the gap eliminator when not in use must be stored, and therefore convenient lengths for both storage and usage must be considered. Still further, the gap eliminator as described, adapts to the curvature of a wall to which it is attached because of its resilient pliant outer shell and the resilient pliancy of the weighted yet buoyant rods slidably received within the shell. It should be recognized that if so desired, a gap eliminator of the type described could be specifically fabricated for a defined radius wall in which the gap eliminator is fabricated to the exact radius and curvature of such wall. Therefore, while the present invention has been disclosed with respect to the preferred embodiments thereof, it will be recognized by those of ordinary skill in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore manifestly intended that the invention be limited only by the claims and the equivalence thereof.

An improved swimming pool cover system which incorporates a gap eliminator for use on pools which have walls of varying height and curvature, the gap eliminator secured to the wall by a cable and a plurality of anchors, the gap eliminator having a sleeve including a weighted buoyant material disposed below the pool cover attached to the cable and a second sleeve having buoyant weighted material disposed above the pool cover attached to the cable, thereby sealing the gap between the pool cover and the wall.

CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part to U.S. application Ser. No. 623,845, entitled PURGING PROCESS, filed June 23, 1984 and now U.S. Pat. No. 4,559,006. BACKGROUND OF THE INVENTION 1. Field of Invention The present invention relates generally to the field of flare gas combustion, and more particularly, but not by way of limitation, to an improved process of purging flare systems and the like. 2. Discussion of Background Flares are devices used throughout the petroleum and chemical industries to burn combustible gases which exit the process and would otherwise flow to the atmosphere as unburned hydrocarbons. Sometimes very large volumes of these gases are released through safety devices to the atmosphere; failure to burn these gases in a flare could result in a serious safety hazard, such as a vapor cloud explosion. A typical prior art flare system may have a series of conduits which connect gas sources to a vertical stack, but other types of flares also have difficulties that are described herein for vertical stacks. A typical stack has several pilot fires burning continuously at the exit port, and combustibles are ignited as they are exhausted to the atmosphere. The burning of large volumes of discharging gas can generate significant radiant heat and the flare stacks are therefore often made quite tall in order to minimize radiant heat damage at ground level. Flares, including the flare stacks just described, are continuously purged with a gaseous fluid to prevent air from entering the exit port and migrating into the stack; such air migration can present dangerous mixtures of air and unburned hydrocarbons. This purging usually consists of flowing a purge gas through the flare system at a rate sufficient to prevent backflow of air down the stack. The purge gas, commonly a fuel gas or nitrogen, serves to keep air out of the stack, thus preventing formation of certain mixtures of air and gas which, when ignited, can result in explosions within the flare stack. Until recent times the amount of purge gas used was of little concern as fuel gas and nitrogen were very inexpensive. However, basic costs of energy have risen dramatically over the past several years and the cost of purge gas has risen as well. As a consequence, several prior art devices have been used which substantially reduce purge gas flow rates required to effectively prevent air migration in flare systems. These prior art devices serve to retard the flow of air down the stack. SUMMARY OF INVENTION The present invention provides an improved purging process in which purge gas is flowed through a flare system at a suffiient flow rate to substantially control the rate of back flow air migration into the exit pot at the exit of the system. The flow of purge gas is periodically interrupted; that is, the flow of purge gas is ceased for a predetermined interval of time during which air begins to migrate into the flare system. Before this admittance of air can result in a hazardous condition within the system, the flow of purge gas is re-established to sweep the air back out of the system. During the interval of time of purge gas flow interruption, the flow rate of flare gas is determined and purge gas is again started during the interruption if certain flow rate conditions occur. This carefully controlled interruption of purge gas flow results in a significant reduction in the amount of purge gas required and thus provides advantageous cost savings. Also, longer flare system life results since the flame at the exit of the system is extinguished during such periods of purge gas interruption; this substantially extends flare tip life because the continuous existence of flame at the exit port inevitably results in deleterious effects on the system. An object of the present invention is to provide an improved purge gas process requiring a minimum amount of purge gas to achieve safe operation of a flare stack system. Another object of the present invention, while achieving the above stated object, is to minimize the cost of safely purging a flare stack system. Yet another object of the present invention, while achieving the above stated objects, is to provide a purging process which extends the operating life of a flare gas system tip. Other objects, advantages and features of the present invention will become clear from the following detailed description when read in conjunction with the accompanying drawings and with the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a semi-detailed schematic representation of one embodiment of a flare gas system to perform the present inventive process. FIG. 2 is a semi-detailed schematic representation of another flare gas system to perform the present inventive process. FIG. 3 is a semi-detailed schematic representation of yet another flare gas system to perform the present inventive process. FIG. 4 is a flare tip assembly that incorporates a reverse flow seal chamber which further reduces the amount of flare gas used in the present inventive process. FIG. 5 is a graphical depiction of tests performed on two types of flare tip systems in the performance of the present inventive process. DESCRIPTION With reference to FIG. 1, waste gases are supplied to a flare system 10 having a flare stack 12 via a conduit 14. The waste gas flows upward through a purge reduction seal 16 to a tip 18 where it exits the flare system 10. The purge reduction seal 16 is not required to practice the invention but is preferred due to its ability to reduce the purge gas flow. The purge reduction seal and flare tip are discussed further hereinbelow. The flare system 10 further comprises a continuous burning pilot 20 disposed near the flare tip 18. The purpose of the pilot 20 is to ignite any gas exiting the flare tip 18. Purge gas flows through a conduit 22 and a motor valve 24 to the base of the flare stack 12. The flow of purge gas continuously sweeps air from the stack when no flow of flare gas via conduit 14 occurs. As discussed herein, the interruption of purge gas flow results in a slow migration of air into the stack via the exit tip 18. Research into this phenomena now allows prediction of the rate at which air migration into the system will occur and thus the length of time that purge flow may be interrupted without excessive amounts of air entering the system. A conventional timer control 26 closes the valve 24 for a predetermined time interval via an electric signal through a conduit 28 connected thereto and signals to reopen valve 24 at the end of the selected time interval. FIG. 2 is another flare system 30 for the practice of the present invention. Except as now indicated, the flare system 30 is identical to the previously described flare system 10, and like numerals appear in FIG. 2 to identify the same components. As shown in FIG. 2, a conventional oxygen analyzer 32 is used to measure the oxygen content in the flare stack 12 and actuate the valve 24 based on the measured oxygen content. That is, the oxygen analyzer 32 is set to signal the opening and closing of the valve 24 via the conduit 28A connected thereto in order to effect the flow of purge gas only when the oxygen content exceeds a safe limit. FIG. 3 shows yet another flare system 40 for the practice of the present invention. As for FIG. 2 above, like numerals are used in FIG. 3 to identify the same components described hereinabove for the flare system 10 and for the flare system 20. In FIG. 3, purge gas flow is periodically interrupted by the oxygen analyzer 32 causing valve 24 to selectively open and close via a signal through conduit 28B connected to the timer control 26 and thus to the valve 24. Thus the timer control 26 is interposed in the control system such that the valve 24 is opened and closed by either the oxygen analyzer 32 or the timer control 26. This adds a control redundancy, and consequently, creates a safer system. A further refinement of the present invention is depicted in FIG. 3 wherein one or more process condition sensors are represented by the sensor 33 disposed to sense a change of a predetermined process condition within the stack 12. For example, where the sensor 33 is a temperature sensor, a change in stack temperature is obtained for use in conjunction with the oxygen analyzer 32 and the timer control 26 to control the purge gas interruption. If preferred, the sensor 33 can as well be located elsewhere such as in the conduit 14, which can prove beneficial in the case where the flare gas passing through the stack 12 is affected by the release of a condensable vapor. Where condensation is occurring in the stack, there is a consequent pulling of air into the flare by attendant pressure reduction. The process condition sensor 33 can also take the form of being an optical, pressure or vacuum sensor. Also, as discussed further hereinbelow, the sensor 33 can be a flow measurement device which is capable of sensing the flow rate of gas in the stack 12; in such a case, the flow sensor 33 can be a conventional device which is preferably capable of determining when the gas flow rate in the stack is within predetermined flow rate ranges, for the purpose described below. A pure reduction seal of the type discussed briefly above and enumerated 16 will now be described with reference to FIG. 4. Shown therein is a single stage flare tip assembly 50 which attaches to the upper end of a conventional, single conduit flare stack 12A and which is constructed in accordance with my U.S. patent application Ser. No. 485,623, Smoke Suppressant Apparatus for Flare Gas Combustion, filed Apr. 18, 1983 and incorporated by reference herein insofar as necessary for purposes of the present teaching. Flare gas discharge from the flare tip assembly 50 will be configured as a relatively thin layer of cylindrically shaped flare gas. The flare tip assembly 50 comprises a bolt-on flare conduit section 52 which extends upwardly from the flare stack 12A, the flare conduit 52 having an open upper end 54. A cylindrically or tubularly shaped flare housing 56 is connected to the flare conduit 52 via a pair of gusset supports 58 and by an annular bottom plate 60 welded to the lower end of the flare housing 56 and to the outer wall of the flare conduit 52. Disposed coaxially within the flare housing 56 is a liner cylinder 62 which is supported via a number of vertically extending divider members (not shown) that weldingly interconnect the liner cylinder 62 and the flare housing 56. Formed between the coaxially disposed liner cylinder 62 and the flare housing 56 is an annular orifice channel 64 which has an exit port at the upper end 66 of the liner cylinder 62, the annular orifice channel 64 being sealed at its lower end by the bottom plate 60. The liner cylinder 62 has a seal plate 68 welded to the internal wall of the liner cylinder 62 and dividing same into a lower portion 70 and an upper portion 72. The flare conduit 52 extends upwardly into the lower portion 70 of the liner cylinder 62, having its upper end 54 disposed below the seal plate 68. Formed between the inner wall of the liner cylinder 62 and the outer wall of the flare conduit 52 is an annularly shaped reverse flow channel 74, the reverse flow channel 74 having fluid communication with the annular orifice channel 64 as shown. If desired, a fluid injector pipe 76 can extend through the walls of the flare housing 56 and the liner cylinder 62 and connected to and in fluid communication with an externally disposed fluid injector 78. In the flare tip assembly 50, flare gas passes upwardly via the flare conduit 52 and flows from the upper ends 54, the upward flow thereof being blocked by the plate 68 which serves to seal the upper portion 72 of the liner cylinder 62. The flare gas is caused to reverse it upward direction to flow downwardly through the annularly shaped reverse flow channel 74 as indicated by the arrows 80 and 82. The lower end of the liner cylinder 62 is disposed somewhat above the bottom plate 60, and the gas discharging from the reverse flow channel 74 is again caused to reverse its direction and to flow upwardly into the annular orifice channel 64, as indicated by the arrows 84; the flare gas discharges at the exit port of the annular flow channel 64 provided at the top of the flare tip assembly 50. The flare gas can be discharged from the annular orifice 64 into the atmosphere in the form of a perimeter zone discharge, or it can be passed to the tip 18 as shown in the previous figures. The flare tip assembly 50 may be equipped with an externally disposed fluid injector assembly 86 and with the conventional pilot 20. Also, the upper portion of the internal wall of the liner cylinder may be lined with a refractory (not shown) if required to protect the structure from the burning flare gas. The flare tip assembly 50 provides a reverse flow seal chamber between the flare conduit 52 and the annular orifice channel 64. During purge operations, this reverse flow seal chamber serves to entrap a portion of the purge gas generally within the space formed in the reverse flow channel 74 below the seal place 68 and the lower portion of the annular orifice channel 64, and this occurs whether the purge gas is heavier or lighter than atmospheric air. The result of this purge gas entrapment is to minimize the amount of purge gas required to retard the backflow of atmospheric air into the flare stack. EXAMPLES A series of tests were performed to determine the rise in oxygen content versus time for two types of flare tips mounted on a reverse flow seal chamber. A basic pipe flare tip consisting of a straight section of pipe was used in one series of tests. This basic pipe flare tip is of a design well known to those skilled in the art and represents the most simple type of flare tip. A flare system of the type depicted in FIG. 4 hereinabove was used in a second series of tests; in contrast to the simple basic flare tip, the flare system 40 represents an advanced technology tip of the latest designs commercially available. Both tips were mounted on conventional reverse flow seal chambers and mounted on stacks. An oxygen analyzer was used to monitor the oxygen content below the reverse flow seal chamber. Natural gas was introduced at the base of the flare stack. Purge gas was used initially to clear all oxygen from the system. The purge gas flow was then stopped and the oxygen content measured versus time. After collection of oxygen measurements, the system was purged again and the decay curve data of FIG. 5 generated. The data varied with type of tip and weather conditions but all fit within the band shown on FIG. 5 between curves 1A and 1B. One series of tests were performed to specifically determine the time required to purge the air from the system versus the flow rate of the purge gas. In these tests, the purging was continued until the oxygen content was less than 1% and then interrupted for one hour. The oxygen content was recorded at the end of one hour and then the purge flow was re-established and the time required to reach an oxygen content of less than 1% measured. Typical results for 18 inch outer diameter vertical flare stack with reverse flow seal as shown in FIG. 4 are provided in the following table. ______________________________________Oxygen @ Oxygen after Minutes fpsstart 1 Hour Purge Time Purge Velocity______________________________________0.95% 1.45% 10 0.0040.85% 1.40% 13 0.0030.90% 1.50% 17 0.002______________________________________ The oxygen concentrations shown in the above table of data are recognized under good engineering practices as being within acceptably safe operating conditions for vertical flare stacks. It is believed that significant deviations from these conditions can be tolerated without presenting a safety hazard. While this data is for a vertical stack and will enable one skilled in the art (using generally accepted extrapolation techniques) to calculate the design requirements for any size vertical flare, it will be understood that one skilled in the art could use similar techniques to predict design criteria for other types of flares, such as, but not limited to, ground flares, pit flares and inclined boom flares now commonly found in the art. It has been determined that purge gas control as described hereinabove saves considerable purge gas. However, if a very small volume of gas is flowing to the flare 12 from its source, the period during which purge gas is terminated, or shut off, may result in an occasional burn back problem. The present invention provides a method of preventing the possibility of burn back during periods of no purge gas flow. Studies of minimum purge gas flow in basic flare tips has indicated that there are three zones, or ranges, of low flow conditions which can occur in a flare gas purge system of the type hereinabove described. These ranges are as follows: ______________________________________Low Range Transition Range High Flow______________________________________Observation: Observation: Observation:No Fire. Fire floats, Fire burns whooshes or hums. outside the stack tip. ##STR1##Riser Velocity Increasing______________________________________ This tabular depiction of observations presents the results of research studies which provided the following results. In the low range of riser velocity (or flow rate) as sensed by the flow or velocity sensor 33 (FIG. 3), no significant fire occurred within the tip, which was determinable from skin temperature measurements. It was assumed that any flame, or burn back, was quickly snuffed due to lack of fuel, air or both. The transition range demonstrated ignition of the flare gas at the tip followed by rapid retreat of the flame down the stack and snuffing of the flame due to lack of oxygen. The high flow range demonstrated fire burning clear of the tip; this is the desired flame characteristic in a purged flare of the type described hereinabove. The present invention recognizes the desirability for further process refinements for protection of flare tips from burn-back due to flare gas discharge such as that which occurs from process leakage or the like during zero purge flow rates as called for in the above described purge gas cut off process. Specifically it has been determined that the flow sensor 33 affords the means, in conjunction with the other components, such as the timer control 26 and motor valve 24 of FIG. 3, for establishing override controls during zero flow of purge gas flow through the flare system 40, as follows, during the interval of time that purge gas is ceased: (1) If the sensor 30 determines that the gas flow rate of flare gas in the stack 12 is in the low range, the purge gas in conduit 22 would remain shut off via the motor valve 24 as described above under the discussion of the flare system 40. (2) If the flow rate of flare gas in the stack 12 during the cessation interval is measured in the transition range during purge gas shut off in conduit 22 (that is, when the process of flare system 40 would call for this no purge condition), the present invention would provide an override control in the timer control 26 so that the motor valve 24, instead of being completely closed, would be opened partially to admit a sufficient amount of purge gas via the conduit 22 to increase the flow rate as sensed by the sensor 33 to be within the high flow range. (3) Finally, if the sensor 33 determines that the flow rate of the flare gas in the stack 12 during the cessation interval is in the high flow range when the purge gas is shut off via the motor valve 24, no override of the timer control 26 would occur. In effect, the present invention presents a refinement to the above described process of flare system 40 in recognition that a complete shut off of the purge gas at intervals, while many times advisable for a particular application, can at times be accompanied by burn back conditions which can be prevented by implementing an override control over such purge shut off, that is, by requiring that flow rate conditions within the stack be present before complete purge shut off can be effected by the purge gas motor valve and its control devices. The following example of the flow rate/purge gas studies will demonstrate further this invention with commentary on the attending observations. EXAMPLE In the determination of the ranges of flow rates for a particular flare system, empiral observations were employed together with certain process parameter measurements. Tests were conducted in three sizes of open pipe flares (6 inch, 18 inch and 36 inch diameters equipped with one or more pilot flames) using natural gas (largely methane) as the flared and destroyed gas. The volume of flare gas flowing to the pipe flare was measured by appropriate means, and from this, the velocity of the flare gas in the pipe flare was readily available by usual calculations. By varying the velocity of the flare gas in the pipe flare while observing the fire phenomenon, the velocity ranges described in the above table could be determined for the flare. Specifically, flare gas flow was varied to establish the velocity ranges where the following occurred during the tests: 1. The fire burned clear of the tip; 2. The fire retreated into the tip but did not go out; 3. The fire retreated into the tip so far that it went out and then reignited several seconds later; and 4. The fire did not burn inside the tip. Data obtainied from the tests, that is, velocity ranges and observed fire phenomenon was correlated, and from these, it was clear that extrapolations can be made to predict flare gas flow rate and expected fire phenomena characteristics for any size of flare. Also, purge gas termination, or reduction to partial flow, during the cessation interval was observed, as indicated, as to its contribution to flame stability at the flare outlet, with the result being that partial purge gas flow determined to increase the total gas velocity (flare and purge gas combined) into the high velocity range did provide the desired flame stability. It was therefore concluded that flame stability can be maintained over a wide range of flare gas velocities while implementing the purge gas cyclic interruptions of the present invention. It should be clear that the above described purging process for controlling the rate of back flow migration by ceasing the flow of purge gas to permit air migration to occur for selected time intervals, subject to the process condition that gas flow rates in the flare stack are maintained within a predetermined flow range, achieves the stated objects of minimizing purge gas consumption while maintaining safe operating conditions within as flare stack system. In fact, the present invention is well adapted to carry out the objects and to attain the ends and advantages mentioned as well as those inherent therein. While presently preferred embodiments have been described for purposes of this disclosures, numerous changes may be made which will readily suggest themselves to those skilled in the art and which are embodied within the spirit of the invention disclosed and as defined in the appended claims.

An improved purging process in which purge gas is flowed through a flare system at a sufficient flow rate to minimize or at least acceptably control the rate of back flow of air migration into the exit port of the system. The flow of purge gas is periodically terminated (or reduced) for a predetermined interval of time during which air begins to migrate into the flare system. During this purge gas cessation interval, the flow rate of the flare gas is sensed, and depending upon predetermined flow rate ranges for the flare gas, the purge gas cessation is continued during the cessation interval or a partial purge gas flow is commenced to assure that the total gas flow rate in the system is maintained above a predetermined flow rate. In any event, once the cessation interval of time has lapsed, the full purge gas flow is re-established to assure that air migration is cleared from the system.

RELATED APPLICATIONS [0001] This application claims the benefit of International Application No. PCT/SE2011/051025, filed Aug. 25, 2011, the disclosure of which is fully incorporated herein by reference. TECHNICAL FIELD [0002] The present invention relates to a wireless telecommunication system, a node (e.g., eNodeB, eNB, BSC, RNC), a procedure latency monitor unit, and a method for measuring the latency of a procedure e.g., radio network procedure, core network procedure where the results of the measured latency may be used for admission control of user equipment (UE) sessions and to guarantee that admitted UEs are served according to their requested Quality of Service (QoS). BACKGROUND [0003] The following abbreviations are herewith defined, at least some of which are referred to within the following description about at least the prior art and/or the present invention. BSC Base Station Controller CDMA Code Division Multiple Access CN Core Network CPU Central Processing Unit EPC Evolved Packet Core ERAB EUTRAN Radio Access Bearers GSM Global System for Mobile Communications LTE Long Term Evolution PLM Procedure Latency Monitor PRB Physical Resource Block QoS Quality of Service RAN Radio Access Network RNC Radio Network Controller RRC Radio Resource Control tPLM Procedure Latency Mean time UE User Equipment WCDMA Wideband Code Division Multiple Access [0021] In a wireless telecommunication system, admission control (capacity management) is a function implemented in the node (e.g., eNodeB, BSC, RNC) that manages a number of UE sessions. Admission control is needed to handle new, ongoing and incoming UE connections due to e.g. handover or roaming or establishment of connections, and to guarantee that admitted UEs are served according to their requested Quality of Service (QoS). In addition, admission control is needed when the offered load is much higher than the node's engineered capacity. For example, when the node (e.g., eNodeB, BSC, RNC) encounters a situation with high load, the node's admission control mechanism has the responsibility to throttle (e.g., reduce) the load so it remains within the node's engineered capacity. This is valid for ongoing, new and incoming UE connections due to e.g. handover. [0022] For example, in LTE the eNodeB's admission control mechanism uses both hard limits (e.g., the number of licenses in use) and dynamic limits (e.g., the utilization ratio of the PRB resources). Basically, the eNodeB is configured to implement its own utilization measure for each internal resource that is a potential bottleneck. And, during the eNodeB operation a different type of traffic pattern will create its own particular bottlenecks. Thus, when designing and programming or configuring the eNodeB it is difficult to predict which internal resources that will run out due to high traffic load and which internal resources that need to be monitored. The eNodeB's internal resources may be for example: Number of connected users Number of bearers per user (signaling and data) CPU utilization Signal buffer sizes [0027] Accordingly, there is and has been a need for enhancing the traditional node (e.g., eNodeB, BSC, RNC) to address these shortcomings and other shortcomings to improve at least the admission control function to handle new, ongoing and incoming UE connections. This need and other needs are satisfied by the exemplary embodiments of the present invention. SUMMARY [0028] A node (e.g., eNodeB, eNB, BSC, RNC), a procedure latency monitor unit, a method, and a wireless telecommunication system that address the shortcomings of the prior art are described in the independent claims of the present application. Advantageous embodiments of the node (e.g., eNodeB, eNB, BSC, RNC), the procedure latency monitor unit, the method, and the wireless telecommunication system have been described in the dependent claims of the present application. [0029] In an aspect of exemplary embodiments of the present invention there is provided a node (e.g., eNodeB, eNB, BSC, RNC) located in a wireless telecommunications network and configured to administer a number of sessions with UEs. The node comprises a procedure latency monitor unit and an admission control mechanism. The procedure latency monitor unit is configured to establish a measurement window associated with a procedure within the wireless telecommunications network and during the measurement window is further configured to measure a predetermined number of delta times, where each measured delta time indicates an amount of time that takes place between a start of the procedure and a stop of the procedure. In addition, the procedure latency monitor unit upon completion of the measurement window is configured to take the predetermined number of measured delta times and is further configured to calculate a mean delta time which is an average of the measured delta times. Furthermore, the procedure latency monitor unit is configured to compare the mean delta time with a predetermined threshold which is also associated with the procedure and if the mean delta time exceeds the threshold then the procedure latency monitor unit is configured to issue a high load signal associated with the procedure. The admission control mechanism is configured to receive the high load signal associated with the procedure and is further configured to activate an admission action. An advantage of the node is that it may better steer the admission control function and determine when an internal resource has reached its engineered capacity. [0030] In yet another aspect of exemplary embodiments of the present invention there is provided a method implemented by a node (e.g., eNodeB, eNB, BSC, RNC) located in a wireless telecommunications network and configured to administer a number of sessions with UEs. The method comprises: (a) establishing, in a procedure latency monitor unit, a measurement window associated with a procedure within the wireless telecommunications network and during the measurement window measuring a predetermined number of delta times, where each measured delta time indicates an amount of time that takes place between a start of the procedure and a stop of the procedure; (b) taking, in the procedure latency monitor unit, the predetermined number of measured delta times upon completion of the measurement window and calculating a mean delta time which is an average of the measured delta times; (c) comparing, in the procedure latency monitor unit, the mean delta time with a predetermined threshold which is also associated with the procedure and if the mean delta time exceeds the threshold then issuing a high load signal associated with the procedure; and (d) receiving, at an admission control mechanism, the high load signal associated with the procedure then activating an admission action. An advantage of the method is that it enables the node to better steer the admission control function and determine when an internal resource has reached its engineered capacity. [0031] In still yet another aspect of exemplary embodiments of the present invention there is provided a procedure latency monitor unit which is part of a wireless telecommunication network. The procedure latency monitor unit comprises a processor and a memory that stores processor-executable instructions therein where the processor interfaces with the memory and executes the processor-executable instructions to enable the following: (a) establish a measurement window associated with a procedure within the wireless telecommunications network and during the measurement window measure a predetermined number of delta times, where each measured delta time indicates an amount of time that takes place between a start of the procedure and a stop of the procedure; (b) take the predetermined number of measured delta times upon completion of the measurement window and calculate a mean delta time which is an average of the measured delta times; and (c) compare the mean delta time with a predetermined threshold which is also associated with the procedure and if the mean delta time exceeds the threshold then issue a high load signal associated with the procedure. An advantage of the procedure latency monitor unit is that it enables the node to better steer the admission control function and determine when an internal resource has reached its engineered capacity. [0032] In yet another aspect of exemplary embodiments of the present invention there is provided a method implemented by a procedure latency monitor unit which is located in a wireless telecommunications network. The method comprises: (a) establishing a measurement window associated with a procedure within the wireless telecommunications network and during the measurement window measuring a predetermined number of delta times, where each measured delta time indicates an amount of time that takes place between a start of the procedure and a stop of the procedure; (b) taking the predetermined number of measured delta times upon completion of the measurement window and calculating a mean delta time which is an average of the measured delta times; and (c) comparing the mean delta time with a predetermined threshold which is also associated with the procedure and if the mean delta time exceeds the threshold then issuing a high load signal associated with the procedure. An advantage of the method is that it enables the node to better steer the admission control function and determine when an internal resource has reached its engineered capacity. [0033] In still yet another aspect of exemplary embodiments of the present invention there is provided a wireless telecommunications network which comprises a core network and a node (e.g., eNodeB, eNB, BSC, RNC) connected to the core network and configured to administer a number of sessions with UEs. The node comprises a procedure latency monitor unit and an admission control mechanism. The procedure latency monitor unit is configured to establish a measurement window associated with a procedure within the wireless telecommunications network and during the measurement window is further configured to measure a predetermined number of delta times, where each measured delta time indicates an amount of time that takes place between a start of the procedure and a stop of the procedure. In addition, the procedure latency monitor unit upon completion of the measurement window is configured to take the predetermined number of measured delta times and is further configured to calculate a mean delta time which is an average of the measured delta times. Furthermore, the procedure latency monitor unit is configured to compare the mean delta time with a predetermined threshold which is also associated with the procedure and if the mean delta time exceeds the threshold then the procedure latency monitor unit is configured to issue a high load signal associated with the procedure. The admission control mechanism is configured to receive the high load signal associated with the procedure and is further configured to activate an admission action. An advantage of the node is that it may better steer the admission control function and determine when an internal resource has reached its engineered capacity. [0034] In yet another aspect there is provided a procedure latency monitor unit which is located in a wireless telecommunications network. The procedure latency monitor unit comprises a processor and a memory that stores processor-executable instructions therein where the processor interfaces with the memory and executes the processor-executable instructions to enable the following: (a) establish a measurement window when a procedure in the wireless telecommunications network has a delta time that exceeds a predetermined threshold, where the delta time is an amount of time that takes place between a start of the procedure and a stop of the procedure; (b) set a number of delta time measurements for the procedure that are to be completed during the measurement window; (c) wait for the procedure to occur; (d) when the procedure occurs, calculate a delta time which indicates an amount of time that takes place between a start of the procedure and a stop of the procedure; (e) decrement by one the number of delta time measurements that need to be completed during the measurement window; (f) determine if completed all of the delta time measurements that were set to be completed during the measurement window; (g) if the result of the determine step is no, then return and perform the wait operation; (h) if the result of the determine step is yes, then: (i) stop the delta time measurement; (ii) calculate a mean delta time which is an average of the measured delta times for the procedure; (iii) check if the mean delta time exceeds a predetermined threshold which is associated with the procedure; (iv) if the result of the check operation is yes, then send a high load signal associated with the procedure; and (v) if the result of the check operation is no, then determine if there is an outstanding high load signal and if not then end otherwise send a cease high load signal associated with the procedure. An advantage of the procedure latency monitor unit is that it enables the node to better steer the admission control function and determine when an internal resource has reached its engineered capacity. [0035] In still yet another aspect of exemplary embodiments of the present invention there is provided a method implemented by a procedure latency monitor unit which is located in a wireless telecommunications network. The method comprises: (a) establishing a measurement window when a procedure in the wireless telecommunications network has a delta time that exceeds a predetermined threshold, where the delta time is an amount of time that takes place between a start of the procedure and a stop of the procedure; (b) setting a number of delta time measurements for the procedure that are to be completed during the measurement window; (c) waiting for the procedure to occur; (d) when the procedure occurs, calculating a delta time which indicates an amount of time that takes place between a start of the procedure and a stop of the procedure; (e) decrementing by one the number of delta time measurements that need to be completed during the measurement window; (f) determining if completed all of the delta time measurements that were set to be completed during the measurement window; (g) if the result of the determining step is no, then return and perform the waiting step; (h) if the result of the determining step is yes, then: (i) stopping the delta time measurement; (ii) calculating a mean delta time which is an average of the measured delta times for the procedure; (iii) checking if the mean delta time exceeds a predetermined threshold which is associated with the procedure; (iv) if the result of the checking step is yes, then sending a high load signal associated with the procedure; and (v) if the result of the checking is no, then determining if there is an outstanding high load signal and if not then end otherwise sending a cease high load signal associated with the procedure. An advantage of the method is that it enables the node to better steer the admission control function and determine when an internal resource has reached its engineered capacity. [0036] Additional aspects will be set forth, in part, in the detailed description, figures and any claims which follow, and in part will be derived from the detailed description, or may be learned by practice of the exemplary embodiments of the present invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as disclosed. BRIEF DESCRIPTION OF THE DRAWINGS [0037] A more complete understanding of the presently described embodiments may be obtained by reference to the following detailed description when taken in conjunction with the accompanying drawings: [0038] FIG. 1 is a block diagram of an exemplary LTE wireless telecommunication system which has eNodeBs configured in accordance with an embodiment of the present invention; [0039] FIG. 2 is a block diagram that illustrates in greater detail the components in one of the eNodeBs shown in FIG. 1 configured in accordance with an embodiment of the present invention; [0040] FIG. 3 is a flowchart illustrating the basic steps of an exemplary method implemented by a procedure latency monitor unit (incorporated within the eNodeB) in accordance with an embodiment of the present invention; [0041] FIG. 4 is a diagram illustrating used to help explain how the procedure latency monitor unit (incorporated within the eNodeB) may perform a latency procedure measurement in accordance with an embodiment of the present invention; and [0042] FIG. 5 is a flowchart illustrating the basic steps of another exemplary method implemented by the procedure latency monitor unit (incorporated within the eNodeB) in accordance with an embodiment of the present invention. DETAILED DESCRIPTION [0043] Referring to FIG. 1 , there is a block diagram of an exemplary LTE wireless telecommunication system 100 which has eNodeBs 102 a , 102 b and 102 c (only three shown) each configured in accordance with an embodiment of the present invention. In this example, the LTE wireless telecommunication system 100 includes a MME/S-GW 104 (e.g., core network 104 ) which has Si interfaces with the three eNodeBs 102 a , 102 b and 102 c . The eNodeBs 102 a , 102 b and 102 c respectively manage their own cells 106 a , 106 b and 106 c which have their own radio cover areas within which there may be one or more UEs 108 . The eNodeBs 102 a , 102 b and 102 c utilize RRC signaling to interface with their respective UEs 108 . In addition, the eNodeBs 102 a , 102 b and 102 c communicate with one another over multiple X2 interfaces. The exemplary LTE wireless telecommunication system 100 may support many UEs 108 and includes many other components which are well known in the art but for clarity are not described herein while the eNodeBs 102 a , 102 b and 102 c or nodes in accordance with the presently described exemplary embodiments are described in detail herein. A detailed description is provided next to explain how the eNodeBs 102 a , 102 b and 102 c are configured to address the shortcomings of the prior art and improve the admission control function to better handle new, ongoing and incoming UE connections. The eNodeBs 102 a , 102 b and 102 c also have many well known components (e.g., receiver, transmitter) incorporated therein but for clarity those well known components are not described herein. [0044] Referring to FIGS. 2 and 3 , there are shown a block diagram and a flowchart respectively illustrating the eNodeB 102 a (for example) and the method 300 implemented therein in accordance with an exemplary embodiment of the present invention. As shown, the eNodeB 102 a includes an admission control mechanism 202 , a procedure latency monitor unit 204 , and an optional traffic measurement unit 206 . The procedure latency monitor unit 204 includes a processor 208 and a memory 210 that stores processor-executable instructions therein where the processor 208 interfaces with the memory 210 and executes the processor-executable instructions to enable the following: (a) establish a measurement window 212 associated with a procedure 214 within the wireless telecommunications network 100 and during the measurement window 212 measures a predetermined number of delta times 216 , where each measured delta time 216 indicates an amount of time that takes place between a start 218 of the procedure 214 and a stop 220 of the procedure 214 (step 302 in FIG. 3 )(see also description associated with FIG. 4 ); (b) take the predetermined number of measured delta times 216 upon completion of the measurement window 212 and calculate a mean delta time 222 which is an average of the measured delta times 216 (see step 304 in FIG. 3 ); and (c) compare the mean delta time 222 with a predetermined threshold 224 which is also associated with the procedure 214 and if the mean delta time 222 exceeds the threshold 224 then issue a high load signal 226 (e.g., raiseHighLoad (procedure) 226 ) associated with the procedure 214 (step 306 in FIG. 3 ). Thereafter, the admission control unit 202 upon receiving the high load signal 226 (e.g., raiseHighLoad (procedure) 226 ) associated with the procedure 214 is configured to activate an admission action 228 . [0045] The traffic measurement unit 206 may be used in conjunction with the procedure latency monitor unit 204 to provide additional information 230 (e.g., dropped UE sessions 230 ) to the admission control mechanism 202 . For example, the traffic measurement unit 206 may be configured to determine the number of sessions with the UEs 108 which are dropped without being requested to be released by the UEs 108 and then report the number of dropped UE sessions 230 to the admission control mechanism 202 . Thereafter, the admission control mechanism 202 upon receiving the high load signal 226 associated with the procedure 214 further determines if the number of dropped UE sessions 230 exceeds a predetermined threshold 232 and if yes then activates the admission action 228 . For example, the admission action 228 may include anyone or a combination of the following: Block one or more new UEs trying to connect to the eNodeB level. Release one or more UEs 108 already connected based on a priority class; Block a new data radio bearer setup. Release of one or more data radio bearers. Reduce observability monitoring. Etc. [0052] If desired, the procedure latency monitor unit 204 may establish additional measurement windows 212 ′ to measure additional delta times 216 ′ for additional different procedures 214 ′ and then calculate additional mean delta times 222 ′ for the additional different procedures 214 ′ where if one or more of the calculated mean delta times 222 ′ exceed a corresponding threshold 224 ′ then issue one or more high load signals 226 associated with the corresponding one or more different procedures 214 ′. In particular, the procedure latency monitor unit 204 for each additional monitored procedure 214 ′ would: (a) establish a measurement window 212 ′ associated with that procedure 214 ′ within the wireless telecommunications network 100 and during the measurement window 212 ′ measures a predetermined number of delta times 216 ′, where each measured delta time 216 ′ indicates an amount of time that takes place between a start 218 ′ of that procedure 214 ′ and a stop 220 ′ of that procedure 214 ′; (b) take the predetermined number of measured delta times 216 ′ upon completion of the measurement window 212 ′ and calculate a mean delta time 222 ′ which is an average of the measured delta times 216 ′; and (c) compare the mean delta time 222 ′ with a predetermined threshold 224 ′ which is also associated with that procedure 214 ′ and if the mean delta time 222 ′ exceeds the threshold 224 ′ then issue a high load signal 226 (e.g., raiseHighLoad (procedure) 226 ) associated with the procedure 214 ′. For example, the procedure latency monitor unit 204 may monitor one or more procedures 214 and 214 ′ which include radio network procedures and/or core network procedures such as anyone of the following: a RRCConnectionSetup. an InitialContextSetup. an ERABSetup. a HandoverPreparation. A procedure that interacts with another node other than UEs 108 . Etc. [0059] Once, the procedure latency monitor unit 204 issues the high load signal 226 which is associated with anyone of the procedures 214 or 214 ′ then the processor 208 may further execute the processor-executable instructions to establish another measurement window 212 or 212 ′ for that procedure 214 or 214 ′ to measure multiple delta times 216 or 216 ′ for that procedure 214 or 214 ′ and then calculate the mean delta time 222 or 222 ′ for that procedure 214 or 214 ′ where if the calculated mean delta time 222 or 222 ′ does not exceed the threshold 224 or 224 ′ for that procedure 214 or 214 ′ then issue a cease high load signal 234 (e.g., ceaseHighLoad (procedure) 234 ) associated with that procedure 214 or 214 ′ (see step 308 in FIG. 3 ). [0060] The procedure latency monitor unit 204 may establish the measurement window 212 or 212 ′ pursuant steps 302 or 308 when the corresponding procedure 214 or 214 ′ has a delta time that exceeds a predetermined threshold 224 or 224 ′ (or different threshold) where the delta time is an amount of time that takes place between a start 218 or 218 ′ of the procedure 214 or 214 ′ and a stop 220 or 220 ′ of the procedure 214 or 214 ′. A more detailed description about when the measurement window 212 or 212 ′ may be established pursuant steps 302 or 308 is provided below with respect to FIG. 4 . [0061] As can be seen, the eNodeB 102 a (for example) described above provides a way of monitoring the procedures 214 and 214 ′ (e.g., radio network procedures, core network procedures) to trigger one or more admission control actions 228 . In particular, the eNodeB 102 a measures the latency of procedures 214 and 214 ′ and when there is an increased procedure time then initiate admission control supervision. Alternatively, the eNodeB 102 a measures the latency of procedures 214 and 214 ′ and the dropped UE sessions 230 and when there is an increased procedure time and an increased UE drop rates then initiate admission control supervision. [0062] For every procedure 214 (for example) used in the supervision of the admission control, there is a defined threshold t 0 224 . In addition, there is a delta time 216 that is measured for each procedure 214 (for example) which is the time between the start 218 of procedure 214 and the stop 220 of the procedure 214 . If no measurement is ongoing for the procedure 214 (for example), then a new measurement window 212 may be established and subsequent delta time 216 measurements started when a delta time breaches the t 0 threshold 224 , i.e. when the first procedure 214 exceeded its maximum delay time (see FIG. 4 ). The measurement window 212 is active for the procedure 214 (for example) until N delta times 216 have been collected (i.e., N procedures 214 have started and completed). Once the measurement window 212 is closed, then a statistical evaluation of procedure delta times 216 may be performed so a determination may be made on whether or not any succeeding admission actions have to be performed, i.e. activate the admission control. [0063] Referring to FIG. 4 , there is illustrated a latency measurement example where for procedure 214 (for example) there is a new measurement window 212 created when a delta time measurement 402 breaches the threshold t 0 224 . Then, after the creation of the new measurement window 212 several N delta times 216 are collected such that the mean delta time 222 may be calculated (i.e., N procedures 214 have started and completed). In this example, N=12. Of course N may take any appropriate value as it is a design parameter. In particular, every procedure 214 and 214 ′ has a measurement window 212 and 212 ′ that is used to create a mean delta time 222 and 222 ′ based on N number of measured delta times 216 or 216 ′ for the respective procedure 214 and 214 ′. When all N delta times 216 and 216 ′ have been measured for the procedure 214 and 214 ′ in the measurement window 212 and 212 ′ then the procedure latency monitor unit 204 calculates the procedure latency mean time (tPLM) 222 and 222 ′ for the monitored procedure 214 and 214 ′. A mean value is used to avoid the adverse effects of any possible oscillating behavior of the function. [0064] The procedure latency monitor unit 204 may collect procedure latency measurements 216 and 216 ′ (delta times 216 and 216 ′) simultaneously for all monitored procedures 214 and 214 ′. Admission control may be triggered if at least one procedure 214 and 214 ′ has a mean delta time 222 and 222 ′ which exceeds its threshold 224 and 224 ′. A possible enhancement is to include a dependency between procedure delta times such as follows: [0000] 1 N  ∑ i = 0 N  Δ   t i = tPLM [0000] The formula above calculates a mean procedure time for all (N) measured procedures. In this case, the admission control is being triggered when all the mean time of all procedures exceeds the configured threshold for overload. [0065] In any case, when all N delta time 216 and 216 ′ measurements for a particular procedure 214 or 214 ′ have been collected, and the decision about whether or not an indication 226 shall be sent to the admission control mechanism 202 has been taken, then the measurement window 212 and 212 ′ shall be closed. A new measurement window 212 and 212 ′ will be started when the next delta time 216 and 216 ′ has breached the t o threshold 224 and 224 ′ for that particular procedure 214 and 214 ′. [0066] Every monitored procedure 214 and 214 ′ has a configurable threshold 224 and 224 ′ at which the admission control mechanism 202 is triggered with a high load signal 226 (raiseHighLoad(procedure) 226 ). The actions 228 that may be performed by the admission control mechanism 202 upon receiving the high load signal 226 may include anyone or a combination of the following (for example): Block one or more new UEs trying to connect to the eNodeB level. Release one or more UEs 108 already connected based on a priority class; Block a new data radio bearer setup. Release of one or more data radio bearers. Reduce observability monitoring. Etc. [0073] After a situation where the procedure latency monitor unit 204 has sent the high load signal 226 (raiseHighLoad(procedure) 226 ) for a corresponding procedure 214 and 214 ′. If the procedure latency monitor unit 204 has determined that the mean delta time 222 has been lowered below the t 0 threshold 224 and 224 ′ for that procedure 214 and 214 ′ after the evaluation of the next measurement window 212 and 212 ′, then any outstanding admission action for that procedure 214 and 214 ′ may be ceased by issuing the cease high load signal 234 (e.g., ceaseHighLoad (procedure) 234 ) towards the admission control mechanism 202 . [0074] Referring to FIG. 5 , there is a flowchart illustrating the basic steps of an exemplary method 500 implemented by the procedure latency monitor unit 204 in accordance with an embodiment of the present invention. Beginning at step 502 , establish the measurement window 212 when the procedure 214 (e.g., procedure A) has a delta time 216 that exceeds the predetermined threshold 224 , where the delta time 216 is an amount of time that takes place between a start 218 of the procedure 214 and a stop 220 of the procedure 214 . At step 504 , set a number of N delta time measurements 216 for the procedure 214 that are to be completed during the measurement window 212 . At step 506 , wait for the procedure 214 to occur. At step 508 , when the procedure 214 occurs, calculate the delta time 216 which indicates an amount of time that takes place between the start 218 of the procedure 214 and the stop 220 of the procedure 214 . At step 510 , decrement by one the number of N delta time 216 measurements that need to be completed during the measurement window 212 . At step 512 , determine if completed all of the N delta time 216 measurements that were set to be completed during the measurement window 212 (e.g., determine if N=0). If the result of the determine step 512 is no, then return and perform the wait step 506 . If the result of the determine step 512 is yes, then at step 514 stop the delta time 216 measurement. At step 516 , calculate the mean delta time 222 which is an average of the measured delta times 216 for the procedure 214 . At step 518 , check if the mean delta time 222 exceeds the predetermined threshold 224 which is associated with the procedure 214 . If the result of the check step 518 is yes, then at step 520 send the high load signal 226 (raiseHighLoad(procedure) 226 ) associated with the procedure 214 to the admission control mechanism 202 . If the result of the check step 518 is no, then at step 524 determine if there is an outstanding high load signal 226 that was previously sent and is still pending with the admission control mechanism 202 . If the result of the determine step 524 is no then end at step 522 . If the result of the determine step 524 is yes, then at step 526 send the cease high load signal 234 (e.g., ceaseHighLoad (procedure) 234 ) associated with the procedure 214 to the admission control mechanism 202 . [0075] From the foregoing, it may be seen that the new measure technique described above aims to cover all internal resources, e.g., if an internal resource is starting to reach its engineered capacity then this should be indicated (or predicted) by the measurement of one or more procedures regardless of the internal resource type. In particular, the new measure technique introduces a way to steer the admission control mechanism 202 and to determine if the internal resource of the eNodeB 102 a (for example) has reached its engineered capacity or not by measuring the latency of procedure(s) 214 and 214 ′ and if desired by monitoring the UE drop levels 230 . For example, in a high load scenario it may be monitored that the completion times for the procedure(s) 214 and 214 ′ are stretched and that abnormal UE drop levels 230 are increasing. An abnormal UE drop level 230 may be determined by monitoring UE Context drops or ERAB drops which occur when the eNodeB 102 a (for example) or the core network performs a release of the UE 108 , or a release of the data radio bearer used by the UE 108 without being requested by the UE 108 . Both these drops will adversely impact the end user. [0076] The procedure latency monitor unit 204 may help accomplish this by implementing a method of measuring delta times 216 on procedures 214 and 214 ′ (stop-start times). Then, when the monitored means delta time 222 for one or several procedures 214 and 214 ′ has breached a certain threshold 224 , when at the same time UE drop level 230 has increased (if this option is used), a high load signal 226 is sent to the admission control mechanism 202 which may then perform subsequent admission control actions 228 . Thus, the procedure latency monitor unit 204 may identify when the eNodeB 102 a (for example) is in a high load situation or is likely to reach a high load situation and give the admission control mechanism 202 an opportunity to reduce the affects of the high load situation or prevent the affects of the high load situation. [0077] The procedure latency monitor unit 204 is shown purely on eNodeB level, but it will also impact the core network's load as the signaling load between eNodeB and CN (e.g, MME/S-GW 104 ) will decrease. This is because the procedure latency measurements may include one or more procedures 214 and 214 ′ that are CN procedure times, which provide end-to-end measurements, e.g., CN to RAN measurements. In addition, the admission control mechanism 202 is distributed amongst the eNodeBs 102 a , 102 b , and 102 c (for example) in the network 100 , so the embodiments of the present invention may also spare CN internal resources at high load scenarios since the eNodeBs 102 a , 102 b and 102 c may, for example, block UE connections that would imply load to the CN. [0078] The exemplary embodiments of the present invention have been described above with respect to a LTE wireless telecommunications network and eNodeBs. However, the embodiments may be practiced in any type of wireless telecommunication network where there is a node (e.g., eNodeB, eNB, base station controller, RNC) that manages a cell in which a radio service may be provided to a UE 108 . For example, the present invention may be practiced in GSM, WCDMA or CDMA wireless telecommunication networks. [0079] Although multiple embodiments have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it should be understood that the invention is not limited to the disclosed embodiments, but instead is also capable of numerous rearrangements, modifications and substitutions without departing from the present invention that as has been set forth and defined within the following claims.

A wireless telecommunication system, a node (e.g., eNodeB, BSC, RNC), a procedure latency monitor unit, and a method are described herein for measuring the latency of a procedure (e.g., radio network procedure, core network procedure) where the results of the measured latency may be used for admission control of user equipment (UE) sessions and to guarantee that admitted UEs are served according to their requested Quality of Service (QoS).

ART FIELD The present invention relates to an appliance for driving sharp pointed fastener elements into objects. In particular, the invention relates to an item of equipment generally described as a gun, referred to also herein as a tacker or tacking appliance, by means of which fastener elements with sharp points present typically in nails, pins and staples of different sizes and shapes, can be driven into wood, plastics and similar materials. The fastener elements in question are graded according to size (length, gauge, etc.) in a number series, each designating a range of fasteners rated as nominally compatible, or rather comparable one with another, as regards the type of use and holding power. BACKGROUND ART Conventionally, the different types of fastener elements referred to above (which will be described more fully in due course) are driven into an object and a support together, for example so as to secure the former to the latter, by means of a suitable pneumatic, electromechanical or entirely mechanical (spring-loaded) tacking appliance. Such appliances are designed traditionally to operate with a single type of fastener, i.e. a nail or pin or staple of precise shape and dimensions, so that in situations where there is a need to use dissimilar fasteners for different purposes, there must also be a number of separate appliances ready to hand, each able to operate with a particular type of fastener. Clearly, such a constraint occasions notable cost disadvantages, and reflects a current state of the art whereby users needing to operate with more than one of the aforementioned types of fastener element are obliged also to purchase or acquire a different appliance for each type. Accordingly, the object of the invention is to overcome the drawback mentioned above by providing an appliance of the type in question that will operate universally with a variety of sharp pointed fastener elements, provided that all are of the same nominal size and strength. BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in detail, by way of example, with the aid of the accompanying drawings, in which: FIG. 1 is a schematic representation of an appliance according to the present invention, shown in a side elevation and partly in section; FIG. 2 shows certain of the parts of an appliance according to the invention, seen from the vertical cutting plane denoted II--II in FIG. 1; FIG. 3 shows a detail of the appliance of FIG. 1, enlarged and in a front elevation; FIGS. 4, 5 and 6 illustrate further parts of an appliance according to the present invention, seen in a horizontal section through A--A, FIG. 1; FIG. 7 shows a detail of the appliance of FIGS. 1 to 6, viewed in plan from above and with certain parts omitted in the interests of clarity; and FIG. 8 shows a detail of the forwardmost part of the appliance disclosed, in an alternative and preferred embodiment. DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 1 of the drawings, 1 denotes a tacking appliance, in its entirety, comprising a substantially horizontal upper housing 2 of which the portion located center-right, in FIG. 1, affords a handgrip 3. The horizontal housing 2 incorporates a chamber (not illustrated) connected by way of a hose 4 with a compressed air supply schematically denoted 5, and communicating at bottom (on the left in FIG. 1) with the uppermost part of a vertically disposed second hollow body 6 by which a forcing element 7 is slidably accommodated and supported in a conventional manner (not illustrated). The forcing element 7 is shown as a flat rod 8, vertically disposed and occupying a plane normal to the viewing plane of FIG. 1, of which the top end is connected in conventional manner (not illustrated) to an actuator element indicated schematically by the block denoted 9. Thus, the forcing element 7 can be provided with an impulsive downward movement each time the actuator element 9 is connected to the compressed air supply 5 by squeezing a manually operated control or trigger 10. A portion of the flat rod 8 accommodated internally of the vertical housing 6 is encircled, likewise in conventional manner, by a coil spring 11 loaded in such a way as to compress during each impulsive downward stroke of the forcing element 7 produced by operating the control 10, spring 11 causes the flat rod 8 to be returned subsequently to a raised at-rest position. The above description relates in particular to a pneumatically operated tacker or staple gun, this clearly being the type in most widespread use, but applies equally well to an electromechanical type of appliance or even to an all-mechanical gun, for example with a spring-loading action. Also forming part of the tacker is a magazine assembly 13, associated at one end with the bottom portion of the vertical housing 6 and supported at the remaining end by a strut 12 extending from the bottom of the horizontal housing 2 (on the right, in FIG. 1). Magazine 13 hold a plurality of sharp pointed fastener elements to be directed in succession toward the bottom end of the forcing element 7. The single fastener element may be one of various types, respectively denoted 14a (broad staple), 14b (narrow staple), 14c (flat pin with rounded head, or brad), 14d (flat and headless pin, or sprig) and 14e (medium width staple) in FIGS. 3 to 7. As seen in FIGS. 1 and 2, the magazine assembly 13 comprises a first channel element 15, occupying a fixed position relative to the housing 2 and having a horizontal member of substantially U-shaped cross-sectional profile disposed with the concave surface facing upwardly. The longitudinal edges of this first channel element 15 are rigidly associated with the longitudinal edges of a second fixed channel element 16, having a horizontal member rigidly associated with the vertical housing 6 and the strut 12 and exhibiting a substantially U-shaped cross-sectional profile, of which the concave surface is directed downwards. The two channel elements 15 and 16 thus combine to create an elongated tubular element 17 extending horizontally in a direction parallel to the axes of the elements 15 and 16. The magazine assembly 13 further comprises a guide element lodged internally of the tubular element 17, disposed parallel with and capable of axial motion in relation to the two channel elements 15 and 16 (as will be described in due course). The said element includes a bar 18 of basically rectangular parallelepiped geometry projecting above the plane occupied by the edges of the first channel element 15 (see FIG. 2). The guide bar 18 comprises a lower portion 19 of essentially rectangular cross section, accommodated within the first channel element 15, which is surmounted by a rigidly associated portion 20 likewise essentially rectangular in section but exhibiting a transverse dimension less than that of the lower portion 19 and affording a longitudinal vertically disposed chase 21 extending the full length of the bar 18 in the axial direction and from the topmost face of the upper portion 20 down to the upwardly directed horizontal surface of the lower portion 19 in the vertical direction. The upper portion 20 is thus divided by the chase 21 into two ribs 22 and 23 disposed one alongside the other, respectively left and right as seen in FIG. 2, of which the latter is marginally narrower, measured horizontally in the transverse direction, than the distance separating the two shanks of a fastener element of the type denoted 14b (narrow staple). The position of the upper portion 20 relative to the lower portion 19 is non-symmetrical, with the result that the guide bar 18 is flanked by two spaces or gaps 20c and 20d of dissimilar widths, proportional respectively to the transverse dimensions S1 and S2 of the fastener elements denoted 14c and 14d, of which the purpose will be described in due course. The longitudinal chase 21 is occupied by a coil spring 24 tensioned by expansion, of which one end is anchored to the part of the magazine assembly 13 on the right of FIG. 1, and the remaining end (that on the left, in FIG. 1) is passed around a pulley 25 freely rotatable about a horizontal axis disposed normal to the viewing plane, and anchored by way of conventional connecting means, denoted 26 in FIG. 7, to a pushing element 27 fashioned from a small rectangular plate bent downwards to a right angle along two longitudinal generators in such a way as to create a cross sectional profile substantially of upturned U shape (see also FIG. 2). The pushing element 27 is accommodated within the upper channel element 16, straddling the upper portion 20 of the guide bar 18 and slidable thus along its own axis. The pulley 25 is supported from one side only by one of the two ribs 22 or 23 (that denoted 22, in the example of the drawings) for a reason that will become apparent. Observing the end of the magazine assembly 13 on the left, as viewed in FIG. 1, it will be seen that the channel elements 15 and 16 are truncated in a vertical plane coinciding substantially with the right hand face presented by the flat rod 8 of the forcing element 7, and that the guide bar 18 is adjustable for axial position in relation to the tubular element 17 by means of a setscrew 28 or 29, according to the thickness S (measured in the same axial direction) of the fastener element 14a, 14b, 14c, 14d or 14e in use. The screw 28 or 29 engages a matching thread afforded by a relative portion of the lower channel element 15, and presents a conical point positioned to interact with a corresponding surface afforded by the guide bar 18 (see FIG. 7), in such a manner that the clearance between the butt end surface 18t of the bar 18 and a reference surface denoted 30a (FIG. 1) can be adjusted to the gauge of the particular staple or tack (which may vary even within a given series). Referring again to FIG. 1, the left hand face of the vertical flat rod 8 descends effectively flush with a parallel surface (that denoted 30a) afforded by a restraint element 30, consisting essentially of a vertically disposed plate 31 connected to the vertical housing 6 and extending down to terminate at a level below that of the magazine assembly 13. The plate 31 of the restraint element 30, which in effect provides the means of guiding and releasing each fastener element ejected, is fashioned with a vertically disposed slot 32 (see FIG. 3) occupying a substantially median position in relation to the transverse dimension of the appliance and partially accommodating a tension element 33' embodied as a leaf spring, of which the top part is supported by the restraint element 30 and a lower portion passes through the slot 32 and toward the adjacent end of the tubular element 17. As illustrated in FIGS. 4 to 6, and particularly in FIG. 5, the plate 31 of the restraint element 30 affords two vertical grooves 33 and 34 fashioned in the surface directed toward the tubular element 17, respectively on the left and on the right as viewed in the drawings in question. The grooves 33 and 34 have dissimilar widths L1 and L2 (respectively proportional to and mirroring the widths of the two gaps 20c and 20d aforementioned) and are positioned substantially in horizontal alignment with the two downwardly directed members 35 of the U-profiled pushing element 27, viewed in a direction parallel to the longitudinal axis of the tubular element 13. In like manner, the profile of the flat rod 8 is matched to the profile of the plate 31, affording a longitudinal recess 8a in the central area partly accommodating the spring 33', and on either side, two projections 8c and 8d disposed and proportioned to mirror the position and widths L1 and L2 of the respective grooves 33 and 34. FIG. 8 shows an alternative embodiment to that described and illustrated thus far, in which the plate 31 has two grooves 32a and 32b, set marginally apart one from the other and serving to accommodate two small leaf springs 33a and 33b of which the respective lower ends are independent, though the top ends will be associated preferably with a single flexible element. While equivalent in concept to the main solution, this arrangement has the advantage that fastener elements of dissimilar dimensions can be accommodated more readily, and in particular: not only the broad staple 14a but also the medium staple 14e of width L3, and the narrow staple 14b of width L4; in this instance it will be one or the other of the two leaf springs 33a or 33b which provides the lateral restraint for the staple in question. The operation of the appliance 1 according to the invention will now be described, with a brief reference only to the workings of those elements which also form a part of a conventional tacker. While the particular manner in which different types of fastener element are accommodated by the appliance 1 is central to the disclosure, and will be described in due course, the method of operation remains the same as in a traditional gun, inasmuch as the fasteners 14a . . . e are purchased in the form of a refill 36 consisting in a strip of the single elements attached one to another and bonded, for example by an application of adhesive material; the strip is loaded into the tubular element 17 and directed gradually toward the restraint element 30 by the pushing element 27 through the force of the spring 24 as the fasteners are consumed. In effect, each time the trigger 10 is squeezed to connect the actuator element 9 with the air supply 5, a single fastener will be driven downward by the forcing element 7 at a point immediately adjacent to the restraint 30, and punched through the object (not illustrated) to be secured. As seen in FIGS. 2 to 9, the fastener elements 14a, 14b, 14c, 14d and 14e considered by way of example for the purpose of the description consist respectively of a broad staple, a narrow staple, a brad, a sprig and a medium width staple. In the case of the user wishing to operate the gun 1 with the broad staple type of element 14a, it suffices to load a refill 36 of these same staples (see FIG. 5) into the tubular element 17, positioned in such a way that the top and side faces of the guide bar 18 are compassed substantially in their entirety. In this situation, the staples 14a are advanced toward the restraint 30 and applied to the selected support in exactly the same manner as for a conventional gun, with the refill 36 riding along the guide bar 18 as the single staples are used up, and without any possibility of the refill or of the single elements 14a losing their position. It will be observed that, as each staple 14a is driven down by the action of the forcing element 7, the lower end of the leaf spring 33' retracts completely into the slot 32, performing no function whatever. In the event of the user wishing to operate the gun 1 with the narrow staple type of element 14b, it suffices to position the appropriate refill 36 (see FIG. 4) in the tubular element 17 in such a manner that only the top face and the sides of the single rib 23 are encompassed. In this situation, the staples 14b advance toward the restraint 30 of the appliance 1 and are applied to the support in the usual manner, though sliding along one rib 23 only of the guide bar 18. The leaf spring 33' now performs a fundamental role in the operation of the gun, by virtue of the fact that the bottom end is able to occupy and maintain its position in the slot 32 (see FIG. 3) without any interference from the staple 14b descending under the action of the forcing element 7. Accordingly, this same bottom end of the leaf spring 33' assumes a position in which a portion of one edge is offered in contact to the lateral surface (the left hand surface in FIG. 3) of the descending staple 14b, whereas the staple 14b, moving downward between the end of the bar 18 and the restraint element 30 and no longer held straight by the rib 23, would not otherwise be sufficiently supported and guided from the side in question and might be driven skew, emerging in an incorrect position. Thus, the spring 33' functions as a second restraint and lateral guide element when utilizing the narrow type of staple. In the case of the medium width staple 14e, it is the arrangement of FIG. 8 that will be adopted (this solution is in fact valid for all five types of pin or staple referred to above, though clearly more complex), thereby exploiting the various size combinations afforded by the inclusion of the two separate leaf springs 33a and 33b. In the case of the user wishing to operate the gun 1 with pointed fastener elements consisting of brads 14c or sprigs 14d, it suffices to insert the corresponding refill 36 (FIG. 6) into the tubular element 17 in a position alongside one respective flank of the guide bar 18 (occupying the relative gap 20c or 20d). In this instance, the elements 14c or 14d advance toward the restraint 30 and will be consumed in the normal fashion, with the refill 36 riding against the respective flank of the bar 18. As seen from FIG. 6, the element 14c or 14d in contact with the restraint element 30 is partly accommodated by the relative groove 33 or 34 and therefore guided positively to a given extent when driven downward by the forcing element 7, without drifting from its correct position; in effect, the plate 31 functions both as a restraint and a guide, with added assistance from the matching profile of the flat rod 8 as described above. It will be evident from the foregoing that the stated object is fully realized in an appliance 1 according to the present invention, by virtue of its ability to operate in an extremely simple and economic manner with a generous number of different fastener elements belonging to a given nominal size range, even of dissimilar thicknesses. No limitation is implied in the description and the accompanying illustrations; for example, the leaf spring 33' need not necessarily pass through the slot 32, but might occupy the space partially and thus remain concealed from the exterior.

A hand-held appliance (1) includes a tubular element (17) to accommodate a bonded strip (36) of staples or tacks (14a . . . e). A guide bar (18) is positioned internally of the tubular element (17) along which the refill strip (36) is slidable. A spring-loaded element (27) pushes the strip (36) in the direction of a restraining plate (30) located at one end of the tubular element (17), and a punch rod (7) separates the staples or tacks singly from the strip and drives them downwards, sliding against the surface of the plate (30). The top part of the guide bar (18) is chased with a longitudinal and vertically disposed groove (21), while the restraining plate (30) affords one or more slits or grooves (32 or 33a, 33b) in which to seat at least one leaf spring (33' or 33a, 33b) extending toward the longitudinal groove (21), or lower, and serving to maintain the correct position of the staple or tack as the rod (7) moves downwardly.

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The invention relates to a waveform shaping circuit which is used in a code transmitting apparatus. [0003] 2. Description of the Related Art [0004] An important component element in a digital code transmitting apparatus is a waveform shaping circuit (hereinafter, referred to as a “Nyquist filter”) for data transmission. In the shaping circuit, in a frequency domain of a signal, an attenuation in a stop band is set to an equal ripple, and in a time domain of a signal, an inter-symbol interference is approximated to “0”. [0005] A construction of a conventional digital Nyquist filter is shown in a block diagram of FIG. 1. [0006] Construction of the digital Nyquist filter will be described hereinbelow with reference to FIG. 1. [0007] First, a symbol rate signal generator 1 is a circuit for generating a symbol rate signal by frequency dividing a clock signal serving as a reference of the operation of the digital Nyquist filter. The symbol rate signal denotes a signal synchronized with a symbol frequency of an input signal. Generally, when an analog/digital converter, which will be explained hereinlater, executes what is called an “oversampling” operation, a frequency of the clock signal is equal to a value that is an integer times of a symbol rate (symbol frequency). In an example of the circuit shown in FIG. 1, it is assumed that the symbol rate is set to 1 Hz, and the frequency of the clock signal is set to 3 Hz. An oversampling number M in this case is defined as follows. M =(clock signal frequency)/(symbol frequency)=3 [0008] An analog/digital converter (hereinafter, simply abbreviated to “ADC”) 2 is a circuit for quantization converting a supplied analog signal into a digital signal comprising a predetermined number of bits such as 8 bits or 16 bits. Therefore, digital signals according to the number of bits are generated from the ADC 2 . That is, circuits subsequent to an impulse generator 3 are provided for every bit of a digital conversion output from the ADC 2 . [0009] The impulse generator 3 is a circuit for converting the digital conversion output from the ADC 2 which changes at the symbol rate of the input signal, into an impulse-shaped signal which changes at the frequency of the clock signal. [0010] A delay element 4 is a circuit for providing a delay synchronized with the sampling clock for the impulse-shaped signal. A coefficient multiplier 5 is a circuit for multiplying an output of a tap of each delay element 4 by a predetermined filtering coefficient for every tap. An adder 6 is a circuit for adding outputs from the coefficient multipliers 5 of the taps. [0011] Subsequently, the operation of the digital Nyquist filter shown in FIG. 1 will be described hereinbelow. [0012] First, an analog input signal is converted into a predetermined digital signal by the ADC 2 . The ADC 2 executes the analog/digital converting operation by a clock signal whose sampling rate is equal to 3 Hz. However, a symbol rate signal of 1 Hz is supplied to an enable terminal which permits the output of the circuit. Therefore, the digital output from the ADC 2 changes synchronously with the symbol rate. [0013] The digital output from the ADC 2 is subsequently supplied to the impulse generator 3 , and converted into an impulse train synchronized with the clock signal of 3 Hz. A state of an input signal S j in the impulse generator 3 is shown in a time chart of FIG. 2A. A state of an output signal X n is shown in a time chart of FIG. 2B. In FIG. 2, in order to make understanding easy, each of the input and output signals is shown by amplitude values quantized to seven levels in a range from +3 to −3 including 0. Each of the actual input and output of the impulse generator 3 is a signal at a logic level obtained by encoding the amplitude value by a predetermined number of bits. The signal at the logic level here is a signal in which each of the encoded bits is expressed by “1” or “0”. [0014] Assuming that, an output of the circuit shown in FIG. 1 is set to Y n , since Y n is a summation of signals which passed through the taps of the digital filter shown in the diagram, it can be expressed in a form as shown by the following equation (1). Y n =C 1,0 X n +C 1,1 X n−1 +C 1,2 X n−2 +C 2,0 X n−3 +C 2,1 X n−4 +C 2,2 X n−5 =ΣC 1,k X n−k +ΣC 2,k X n−k−3   (1) [0015] (where, a sum signal “Σ” in the equation expresses the summation in a range from k=0 to 2 with respect to a suffix k. It is defined that “Σ” in the mathematical expressions disclosed in the following description has a meaning similar to that mentioned above.) [0016] In the equation (1), n denotes an integer and has a value to which +1 is added every sampling period of the clock signal. Coefficients C 1,0 to C 2,2 are filtering coefficients which have been predetermined for the coefficient multipliers 5 shown in FIG. 1, respectively. [0017] Signals X i (X n to X n−5 ) of the respective taps in the digital filter in FIG. 1 can be expressed by the following equations, as will be obviously understood from the time chart of FIG. 2B. X i =X i ( i mod 3 =0), X i =0( i mod 3 ≠0)  (2) [0018] where, “mod” (modulo) is an operator which is used to classify the whole integer by a remainder of a division. That is, “i mod 3” denotes that an integer i is classified into three groups by remainders 0, 1, and 2 which are obtained when the integer i is divided by 3. [0019] That is, the equations (2) denote the following meaning. Only when the remainder which is obtained by dividing the suffix i of the signal X i by 3 is equal to 0 (for example, X 0 , X 3 , X 6 , . . . in FIG. 2B), X i =X i . When the remainder is equal to 1 or 2 (for example, X 1 , X 2 , X 4 , . . . in FIG. 2B), X i =0. [0020] Subsequently, consideration is given to a suffix (n−k) of X in the first term of the right side in the equation (1). Since k can have only three values 0, 1, and 2, it is assumed that k=n mod 3 . By substituting k =n mod 3 into the suffix (n−k) of X of the first term of the right side in the equation (1), (n−k) is expressed by the following equation (3). n−k=n −( n mod 3 )  (3) [0021] Further, a remainder which is obtained by dividing the equation (3) by 3 becomes as follows. ( n−k ) mod 3 =( n −( n mod 3 )) mod 3 =0 [0022] The equation is a calculation such that a value obtained by subtracting a remainder obtained by dividing n by 3 from the integer n is further divided by 3 and a resultant remainder is obtained. A result of the calculation is, therefore, equal to 0. [0023] From those results and the conditions of the equations (2), only when k=n mod 3 , X n−k =X n−k . In cases other than the case where k=n mod 3 , X n−k =0. The first term of the right side of the equation (1), therefore, can be simplified as follows. ΣC 1,k X n−k =C 1,(n mod 3) X n−(n mod 3)   (4) [0024] Now, consideration is given to the input/output signals of the impulse generator 3 in FIG. 1. As will be understood from FIG. 2A or 2 B, only the input signal at the time when the output is X 0 , X 3 , X 6 , . . . is meaningful. An output signal X in the equation (4) can be expressed as follows by using an input signal S. X n−(n mod 3) =S j   (5) [0025] where, J is an integer and a value which is increased by +1 every 1 symbol period. [0026] By substituting the equation (5) into the equation (4), the first term of the right side of the equation (1) can be expressed as follows. ΣC 1,k X n−k =C 1,(n mod 3) S j   (6) [0027] Subsequently, consideration is given to a suffix (n−k−3) of X with respect to the second term of the right side of the equation (1). Also in this case, assuming that k=n mod 3 in a manner similar to the case of the first term, the suffix can be expressed as follows. n−k− 3 =n −( n mod 3 )−3 [0028] By using a remainder which is obtained by dividing it by 3, the following equation is obtained. ( n−k− 3) mode 3 =( n −( n mod 3 )−3) mod 3 =0 [0029] By the conditions of the equations (2), only when k=n mod 3 , X n−k−3 =X n−k−3 [0030] When k≠n mod 3 , X n−k−3 =0 [0031] The second term of the right side of the equation (1) can be simplified as follows in a manner similar to the first term of the right side. ΣC 2,k X n−k−3 =C 2,(n mod 3) X n−(n mod 3)−3   (7) [0032] If the output signal X is expressed by the input signal S of the impulse generator 3 in FIG. 1, the following equation is obtained. X n−(n mod 3)−3 =S j−1   (8) [0033] The second term of the right side of the equation (1) can be, therefore, expressed as follows by the equations (7) and (8). ΣC 2,k X n−k−3 =C 2,(n mod 3) S j−1   (9) [0034] From those results, the equation (1) showing the output signal Y n can be simplified as follows by the equations (6) and (9). Y n =C 1,(n mod 3) S j +C 2,(n mod 3) S j−1   (10) [0035] The output signal Y n is supplied to a digital/analog converter (not shown) as necessary, and becomes an analog signal subjected to a waveform shaping process. [0036] In the circuit shown in FIG. 1, filtering characteristics of a desired order can be achieved by setting a value of the number N of taps of the filter (N=6 in the circuit of FIG. 1), and values of the filtering coefficients C 1,0 to C 2,2 to proper numerical values, respectively. [0037] In the digital Nyquist filter, there is a problem that, if the filtering characteristics are complicated and are set to a high order, the number of taps increases and the scale of the circuit is substantially increased. There is also a problem that in association with an increase in circuit scale, the summation of delay times which are due to delay elements and coefficient multipliers included in the circuit increases, and an operating speed of the filter decreases. OBJECT AND SUMMARY OF THE INVENTION [0038] The invention is intended to overcome the above-discussed problems, and it is an object of the invention to provide a digital Nyquist filter in which a circuit scale is small and an operating speed is high. [0039] According to the invention, there is provided a waveform shaping circuit for sampling an analog input signal and performing a waveform shaping process, comprising: [0040] an analog/digital converting circuit for sampling the input signal on the basis of a sampling clock, thereby digitizing it; at least one delay circuit for providing a delay synchronized with a symbol rate of the input signal for an output signal of the analog/digital converting circuit; a coefficient selecting circuit for sequentially selecting one of a plurality of predetermined characteristics values synchronously with the sampling clock and setting the selected characteristics value to a predetermined coefficient; a multiplying circuit for multiplying each of an input signal and an output signal of the delay circuit by the predetermined coefficient, thereby obtaining at least two multiplication outputs; and an adding circuit for adding the multiplication outputs. BRIEF EXPLANATION OF THE DRAWINGS [0041] [0041]FIG. 1 is a block diagram showing a construction of a conventional digital Nyquist filter; [0042] [0042]FIGS. 2A and 2B are time charts showing input and output signals in an impulse generator in a circuit of FIG. 1; [0043] [0043]FIG. 3 is a block diagram showing the first embodiment of a digital Nyquist filter based on the invention; [0044] [0044]FIG. 4 is a memory constructional diagram showing the relation between addresses and stored data in a coefficient ROM circuit shown in the block diagram of FIG. 3; [0045] [0045]FIG. 5 is a time chart showing the operations of portions around a coefficient generating unit shown in the block diagram of FIG. 3; and [0046] [0046]FIG. 6 is a block diagram showing the second embodiment of a digital Nyquist filter based on the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0047] The first embodiment of a digital Nyquist filter according to the invention is shown in a block diagram of FIG. 3. [0048] First, a construction of the embodiment will be described with reference to FIG. 3. Since a symbol rate signal generator 10 and an analog/digital converter (hereinafter, simply abbreviated to “ADC”) 20 are the same as those in the conventional circuit shown in FIG. 1, their description is omitted here. [0049] A D-type flip-flop (hereinafter, simply abbreviated to “DFF”) 30 latches a logic level of an input D in response to a rising or falling edge of a clock signal. The input D at this time is set to a logic level of an output Q. That is, the DFF 30 is a flip-flop for causing a delay of one clock pulse. In the embodiment, the DFF 30 is provided with an input terminal of an enable (ENABLE) signal for permitting or inhibiting output oh the DFF 30 . A symbol rate signal from the symbol rate signal generator 10 is supplied to the input terminal. [0050] As mentioned above, the ADC 20 is a circuit for sampling a supplied analog signal in accordance with the clock signal, and converting the supplied analog signal into a digital signal comprising a predetermined number of bits such as 8 bits or 16 bits. Therefore, digital signals according to the number of bits are outputted from a digital conversion output (DAT) of the ADC 20 . That is, in a manner similar to the case of FIG. 1, circuits subsequent to the DFF 30 are provided for every bit of the digital conversion output from the ADC 20 except for a coefficient generating unit 40 , which will be explained hereinbelow. [0051] The coefficient generating unit 40 comprises a ternary counter 41 , a C 1 coefficient ROM 42 , and a C 2 coefficient ROM 43 . The ternary counter 41 is, for example, a binary counter in which the clock signal is used as a count pulse. Count-up outputs of the counter 41 are assumed to be Qb and Qa (it is assumed that Qa is set to the LSB (Least Significant Bit)). Qa and Qb change cyclically by the ternary notation like [Qb, Qa=0, 0]→[Qb, Qa=0, 1]→[Qb, Qa=1, 0]→[Qb, Qa=0, 0]→ . . . synchronously with the clock pulses. [0052] Each of the C 1 coefficient ROM 42 and C 2 coefficient ROM 43 generates data which has previously been stored in an address to a data output terminal DAT in response to an applied address signal. Contents of the data, which is stored into those ROM circuits, are the filtering coefficients mentioned above. Among the filtering coefficients, C 1,0 , C 1,1 , and C 1,2 have been stored in the C 1 coefficient ROM 42 , and C 2,0 , C 2,1 , and C 2,2 have been stored in the C 2 coefficient ROM 43 , respectively. [0053] A relation between a memory address in each ROM circuit and each of the filtering coefficients stored in the ROM circuit is shown in FIG. 4. A memory area in the ROM circuit is not limited to the example shown in FIG. 4. When a order of a filter which is realized increases, since the number of filtering coefficients which are necessary also increases, naturally, the number of addresses in the ROM circuit and the memory area to store the data also increase. [0054] In the embodiment, the count-up output of the ternary counter 41 is connected to the addresses of the C 1 coefficient ROM 42 and C 2 coefficient ROM 43 , respectively. The data outputs (DATs) from ROM circuits 42 and 43 are connected to multipliers 51 and 52 , respectively. [0055] The multiplier 51 is a circuit for multiplying the output data from the C 1 coefficient ROM 42 by the input signal S j to the DFF 30 . The multiplier 52 is a circuit for multiplying the output data from the C 2 coefficient ROM 43 by an output signal S j−1 from the DFF 30 . An adder 60 is a circuit for adding outputs of those two multipliers. Arithmetic operating processes of the multiplication and addition are executed every bit constructing S j and S j−1 as digital data. [0056] In the embodiment shown in FIG. 3, a clock signal of a frequency of 3 Hz is used as a sampling clock serving as a reference of the operation of the filter. A frequency of 1 Hz is used as a symbol rate of the input signal. Also in the embodiment, therefore, the oversampling number M is obtained as follows. M =(clock signal frequency)/(symbol frequency)=3 [0057] Further, it is assumed that filtering characteristics serving as a base of the filter circuit shown in FIG. 3 are also the same as the filtering characteristics of the filter circuit shown in FIG. 1. In a construction of a digital Nyquist filter which can be achieved by the embodiment, therefore, the number of taps is equal to N=6. It is also assumed that filtering coefficients at the respective taps have six values C 1,0 to C 2,2 as values similar to the values in the case of FIG. 1. [0058] The construction of the embodiment is not limited to the number of taps and the values of the filtering coefficients. That by design is, it is assumed that the number of taps and the values of the filtering coefficients may be changed, and can have various values in order to achieve desired filtering characteristics. [0059] The operation of the embodiment shown in the block diagram of FIG. 3 will be described hereinbelow. [0060] First, the analog input signal is converted into a digital signal of a predetermined number of bits by the ADC 20 . The ADC 20 executes the analog/digital converting operation synchronously with a clock signal having a sampling rate equal to 3 Hz. However, a symbol rate signal from the symbol rate signal generator 10 is supplied to an enable terminal which permits the output of the circuit. The digital output from the ADC 20 , therefore, changes synchronously with the symbol rate (1 Hz). [0061] The digital output from the ADC 20 is supplied to the DFF 30 . The DFF 30 is a flip-flop of a D type for latching the input D by the clock signal and generating output Q. In the circuit of FIG. 3, an output of the DFF 30 is inhibited or permitted by the symbol rate signal from the symbol rate signal generator 10 . The logic level of the input D is, therefore, set into an output Q of the DFF 30 every period of the symbol rate signal. One period of the symbol rate signal corresponds to three periods of the clock signal serving as a sampling pulse as shown by the oversampling number M (M=3). That is, assuming that the input signal of the DFF 30 is set to S j , then the output signal of the DFF 30 becomes the input signal S j−1 of one prior symbol period. [0062] The clock signal (3 Hz) is supplied also to the coefficient generating unit 40 , and supplied as a count clock to the ternary counter 41 in the coefficient generating unit 40 . Qa and Qb as count-up outputs of the ternary counter 41 are connected to the memory addresses of the C 1 coefficient ROM 42 and C 2 coefficient ROM 43 . The memory addresses of the ROM circuits 42 and 43 , therefore, change cyclically in accordance with the count-up of the ternary counter 41 . The output data from the C 1 coefficient ROM 42 and C 2 coefficient ROM 43 , that is, the filtering coefficients shown in FIG. 4 also change cyclically in accordance with the change in memory addresses. [0063] The output data from the C 1 coefficient ROM 42 and C 2 coefficient ROM 43 are multiplied with the input signal S j or the output signal S j−1 of the DFF 30 in the multiplier 51 or 52 , respectively. After that, the two multiplication results are subjected to an adding process every corresponding bit in the adder 60 , and become the output signal Y n . [0064] The count-up operation of the ternary counter 41 described above, the changes in memory addresses in the two ROM circuits and output data, and the relation between the input signal S j and the output signal S j−1 of the DFF 30 are shown in a time chart of FIG. 5. [0065] The output signal Y n generated by above mentioned processes is supplied to a digital/analog converter (not shown) as necessary, and reproduced as an analog signal subjected to a waveform shaping process. [0066] Finally, a point that the output signal Y n of the circuit shown in FIG. 3 is equal to the output of the digital Nyquist filter according to the conventional circuit shown in FIG. 1 will be proved. [0067] First, an output of the multiplier 51 is assumed to be A. A denotes a multiplication result of the input signal S j to the DFF 30 and the filtering coefficients C 1,0 , C 1,1 , and C 1,2 as output data from the C 1 coefficient ROM 42 . A can be, consequently, expressed by the following equation. A=C 1,(n mod 3) S j   (11) [0068] Similarly, an output of the multiplier 52 is assumed to be B. B denotes a multiplication result of the output signal S j−1 from the DFF 30 and the output data C 2,0 , C 2,1 , and C 2,2 from the C 2 coefficient ROM 43 . B can be, consequently, expressed by the following equation. B=C 2, (n mod 3) S j−1   (12) [0069] The output Y n of the circuit shown in FIG. 3 is obtained by adding the outputs of the multipliers 51 and 52 by the adder 60 . Y n , therefore, can be expressed as follows. Y n =A+B   (13) [0070] When the equations (11) to (13) shown above are collected, the output Y n of the circuit shown in FIG. 3 is as follows. Y n =C 1,(n mod 3) S j +C 2,(n mod 3) S j−1   (14) [0071] The equation (14) is equivalent to the output Y n of the conventional digital Nyquist filter shown in the equation (10) mentioned above. Consequently, it is proved that the circuit according to the embodiment shown in FIG. 3 shows the same operation as that of the conventional digital Nyquist filter shown in FIG. 1. [0072] As described above, according to the embodiment, in the digital Nyquist filter which previously required N taps, the number of taps can be reduced to N/M (M is the oversampling number). Even in case of constructing a digital Nyquist filter of a high order, a circuit scale of the filter can be miniaturized. The processing speed is also improved owing to the reduction of the number of elements constructing the circuit. [0073] The second embodiment of a digital Nyquist filter based on the invention is now shown in a block diagram of FIG. 6. [0074] Also in the second embodiment, the clock signal of the frequency of 3 Hz is used as a sampling clock serving as a reference of the operation of the filter. The frequency of 1 Hz is used as a symbol rate of the input signal. Further, it is assumed that filtering characteristics serving as a base of the filter circuit are the same as the filtering characteristics of the filter circuit mentioned above. In a construction of the digital Nyquist filter which can be achieved by the embodiment, therefore, the number of taps is equal to N=6. It is also assumed that filtering coefficients at the respective taps have six values C 1,0 to C 2,2 as values similar to the values in the cases of FIGS. 1 and 3. The number of taps and the values of filtering coefficients may be changed by design, and the embodiment is not limited to the above-mentioned values. [0075] The construction of the second embodiment will be described with reference to FIG. 6. First, the circuit of FIG. 6 comprises: the symbol rate signal generator 10 ; the analog/digital converter 20 ; the D-type flip-flops 30 ; the adders 60 ; coefficient multipliers 70 ; and an output scanner 80 . In the construction, the symbol rate signal generator 10 , ADC 20 , DFF 30 , and adder 60 are the same as the component elements in the first embodiment shown in FIG. 3. An explanation regarding the above-identified component elements is, therefore, omitted here. [0076] The coefficient multiplier 70 is a circuit for multiplying the signal on each of the input side and the output side of the DFF 30 by predetermined filtering coefficients. In each coefficient multiplier 70 shown in FIG. 6, the filtering coefficients C 1,0 and C 2,0 have been set into a pair of coefficient multipliers at the upper stage, the filtering coefficients C 1,1 and C 2,1 have been set into a pair of coefficient multipliers at the middle stage, and the filtering coefficients C 1,2 and C 2,2 have been set into a pair of coefficient multipliers at the lower stage, respectively. [0077] The output scanner 80 is a circuit for sequentially repetitively scanning outputs from the adders 60 in FIG. 6 synchronously with the clock signal (3 Hz). [0078] A circuit group comprising the DFF 30 , coefficient multiplier 70 , and adder 60 shown at each of the upper, middle, and lower stages and the output scanner 80 are provided for each bit of the digital conversion output signal from the ADC 20 . [0079] Subsequently, the operation of the circuit shown in FIG. 6 will be described hereinbelow. [0080] In the embodiment, the input analog signal is converted into a predetermined digital value by the ADC 20 . Further, a delay synchronized with the symbol rate is applied to the digital signal by the DFF 30 . The above point is similar to that in the case of the first embodiment shown in FIG. 3. In the case of the second embodiment, however, the digital conversion output from the ADC 20 is supplied simultaneously to the three circuit groups at the upper, middle, and lower stages shown in FIG. 6. A delay corresponding to one symbol period is added by the DFF 30 included in each circuit group. [0081] In the three circuit groups, the multiplying processes of the filtering coefficients C 1,0 to C 1,2 and C 2,0 to C 2,2 are executed by the coefficient multiplier 70 to the input signal S j and the output signal S j−1 of each DFF 30 , respectively. Outputs of a pair of coefficient multipliers 70 are added by the adder 60 included in each circuit group. Addition results Y 0 to Y 2 are collected as an output signal from each circuit group to the output scanner 80 . [0082] The output scanner 80 sequentially scans the output signals Y 0 to Y 2 from the circuit groups at a speed synchronized with the clock signal. The output scanner 80 generates a scan output as an output signal Y n of the filter circuit. That is, the output signals from the circuit groups repetitively appear as Y 0 →Y 1 →Y 2 →Y 0 → . . . in the output of the circuit shown in FIG. 6 synchronously with the clock signal. [0083] The output signal Y n formed by the above-mentioned processes is supplied to a digital/analog converter (not shown) as necessary, and becomes an analog signal subjected to a waveform shaping process. [0084] Finally, the point that the output signal Y n is equal to the output of the conventional filter circuit even in the second embodiment will be proved. [0085] The output signal Y n of the filter circuit shown in FIG. 6 is obtained by sequentially repetitively switching the outputs Y 0 , Y 1 , and Y 2 of the adders 60 synchronously with the clock signal. Y n can, therefore, be expressed as follows. Y n =Y (n mod 3)   (15) [0086] The output signals Y (n mod 3) of the adders 60 are obtained by adding the resultant signals obtained by multiplying the input signal S j of the DFF 30 by the filtering coefficients C 1,0 , C 1,1 , and C 1,2 and the resultant signals obtained by multiplying the output signal S j−1 of the DFF 30 by the filtering coefficients C 2,0 , C 2,1 , and C 2,2 . Y (n mod 3) can be, therefore, expressed as follows. Y (n mod 3) C 1,(n mod 3) S j +C 2,(n mod 3) S j−1   (16) [0087] The output signal Y n is as follows by the equations (15) and (16). Y n C 1,(n mod 3) S j +C 2,(n mod 3) S j−1   (17) [0088] The equation (17) is equal to the output signal Y n of the conventional digital Nyquist filter shown in the equation (10). [0089] As described above, according to the embodiment, the output scanner 80 scans the output from the adder 60 included in each circuit group synchronously with the sampling clock. It is, therefore, sufficient that a processing speed of each adder 60 is equal to 1/M (M: oversampling number) of the sampling rate, that is, the symbol rate of the input signal. In the first embodiment shown in FIG. 3, since the filtering coefficients are sequentially updated synchronously with the sampling clock from the ROM circuit, the adder has to operate at the sampling rate. [0090] Assuming that, therefore, a maximum operation sampling rate in the first embodiment is set to Fmax. In case of constructing the digital filter of the second embodiment by using an adder of the same processing speed as Fmax, a maximum operation sampling rate in the second embodiment is equal to Fmax×M. That is, according to the second embodiment, an operating speed of the digital filter can be increased M times. [0091] As described in detail above, according to the first embodiment of the invention, the number of taps constructing the digital Nyquist filter can be reduced, the miniaturization and power saving of the circuit can be achieved, and the processing speed can be improved. According to the second embodiment of the invention, even in case of using the circuit elements of the same speed as the conventional circuit, the processing speed of the digital Nyquist filter can be improved. [0092] It is understood that the foregoing description and accompanying drawings set forth the preferred embodiments of the invention at the present time. Various modification, additions and alternative designs will, of course, become apparent to those skilled in the art in light of the foregoing teachings without departing from the spirit and scope of the disclosed invention. Thus, it should be appreciated that the invention is not limited to the disclosed embodiments but may be practiced within the full scope of the appended claims. [0093] This application is based on a Japanese Patent Application No. 2001-308869 which is hereby incorporated by reference.

A small sized digital Nyquist filter having a high processing speed is provided. A delay in a delay element in the digital Nyquist filter is synchronized with a symbol rate of an input signal, and filtering coefficients at respective taps in the filer are sequentially selected synchronously with a sampling clock in accordance with a predetermined procedure, thereby reducing the number of taps to 1/oversampling number.

[0001] This application claims priority from provisional patent application 60/456,692 filed Mar. 21, 2003. FIELD OF THE INVENTION [0002] The present invention relates generally to the construction field. More specifically, the present invention relates to the fields of customized, remodeled, and partitioned indoor and outdoor residential, commercial, and recreational spaces. BACKGROUND OF THE INVENTION [0003] Living, working, and recreational spaces frequently must be divided into partitions. Restaurants are required by municipal ordinance to provide designated non-smoking areas. Population growth and constrained budgets force schools to divide classrooms, libraries, or laboratories. Museums may need temporary panels for displaying loaned art or permanent dividers for displaying donated art. Businesses may need to quickly partition spaces to accommodate unplanned workforce expansion, new product lines, or the addition of employee daycare facilities. Newly implemented security concerns have forced airports to quickly add passenger and baggage screening area partitions, and could present a need for emergency containment of airborne contaminants and toxins. SUMMARY OF THE INVENTION [0004] There are many needs for temporary, semi-permanent, and permanent partitions and walls for which typical construction methods are too time-consuming and costly. There is a need for economical, quickly constructed dividers, panels, barriers, sound baffles, decorations, theater sets, animal corrals, children play areas, or other divisions of space. The present invention enhances the construction field with a system of pre-formed interlocking components that can be cut to desired lengths and assembled on site into frames that can be anchored to any solid surface with conventional fasteners and adhesives. The frames can receive and hold panels of any solid material including wood, composite, metal, granite, glass, plastic, sheetrock, and cloth. A plurality of frames can be interlocked with each other in parallel, perpendicular, or other angular orientations to form customized partitions and walls. The present invention permits on-site construction of customized partitions and walls in a timely and cost-effective manner. BRIEF DESCRIPTION OF THE DRAWINGS [0005] [0005]FIG. 1 is an end view of one embodiment of a base member 100 of the present invention. [0006] [0006]FIG. 2 is an end view of one embodiment of one of the members 200 of the present invention capable of capturing a member such as panel member 1000 and mating with a member such as member 100 . [0007] [0007]FIG. 2 a is an isometric view of one embodiment of one of the members 200 of the present invention capable of capturing a member such as panel member 1000 and mating with a member such as member 100 . [0008] [0008]FIG. 3 is an end view of one embodiment of one of the members 300 of the present invention capable of mating with a member such as member 200 . [0009] [0009]FIG. 4 is an end view of one embodiment of one of the members 400 of the present invention capable of mating with one or two members such as member 200 . [0010] [0010]FIG. 5 is an end view of one embodiment of one of the members 500 of the present invention capable of mating with one or two members such as member 200 . [0011] [0011]FIG. 6 is an end view of one embodiment of one of the members 600 of the present invention capable of mating with one or two members such as member 200 . [0012] [0012]FIG. 7 is an end view of one embodiment of one of the members 700 of the present invention capable of mating with as many as four members such as member 200 . [0013] [0013]FIG. 8 is an end view of one embodiment of a present invention frame assembly comprising a base member 100 , two members 200 , a member 400 , and a panel member 1000 . DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT [0014] [0014]FIG. 1 shows one embodiment of one of the members of the present invention. It is a two-part base member 100 . Member 1 can be attached with conventional fasteners or adhesives to a surface 99 upon or against which a partition or wall of the present invention is to be attached. [0015] [0015]FIG. 2 shows one embodiment of one of the members of the present invention. When the male dovetail feature, as commonly understood in the carpentry and building trades, of member 2 is received and seated in the female dovetail feature of member 100 , created by the proximity of members 4 and 1 , and member 4 of member 100 is pushed against member 1 of member 100 and attached to mounting surface 99 , to member 1 , or both, member 2 is captured and secured. A panel 1000 can be secured in member 200 by capturing it between member 2 and member 5 and securing member 5 to member 2 with any number of readily available fasteners, including nails, screws, clamps, or adhesives. [0016] [0016]FIG. 2 a illustrates a panel member 1000 captured in one embodiment of member 200 . Member 5 is pushed against members 2 and 1000 , and secured with fasteners or adhesive (not shown) so that panel member 1000 is securely captured. [0017] [0017]FIG. 3 shows one embodiment of one of the members of the present invention. The female dovetail feature of member 7 can receive any member having a matching male dovetail feature. For example, the female dovetail feature of member 7 can receive the male dovetail feature of member 2 , or a similar member with a male dovetail feature, thus creating a member comprised of members 200 and 300 . A panel 1000 can be secured in member 300 by capturing it between member 7 and member 6 and securing member 6 to member 7 with any number of readily available fasteners, such as screws, or adhesives. Thus, the composite member consisting of members 200 and 300 can act as a joining device between two panels 1000 . [0018] [0018]FIG. 4 shows one embodiment of one of the members of the present invention. Member 400 provides for extension of partitions and walls. It provides two female dovetail features 40 and 41 in which members with male dovetail features, such as member 200 , or a similar member with a male dovetail feature, can be received. The two member 400 female dovetail features 40 and 41 illustrated in FIG. 4 are situated in member 400 at equal angles from the member 400 axis of symmetry 42 . If the equal orientation angles of the female dovetail members are, for example, 45 degrees, member 400 , assembled with a member 200 , or a similar member with a male dovetail feature, received in both of its female dovetail members 40 and 41 , provides a joining device between two perpendicular panels 1000 . Member 400 could be constructed of two mirror-image blocks that are attached with commonly understood fasteners or adhesive so that they share the common surface in the symmetry plane 42 . [0019] In another embodiment of the FIG. 4 member 400 , the female dovetail features 40 and 41 can be situated at dissimilar angles from the axis of symmetry 42 . Such an embodiment would provide a joining device between two panels 1000 that describe an angle that could range from a small acute angle to 180 degrees. [0020] [0020]FIG. 5 shows one embodiment of one of the members of the present invention. Member 500 provides two opposed female dovetail features 50 and 51 in which members with male dovetail features, such as member 200 , or similar members having a male dovetail feature, can be received. The two opposed member 500 female dovetail features 50 and 51 illustrated in FIG. 5 are mirror images. When a member 200 , or a similar member with a male dovetail feature, is received in both of the member 500 female dovetail features 50 and 51 , member 500 becomes a device for joining two coplanar panels 1000 . [0021] In another embodiment of member 500 , the female dovetail features 50 and 51 on opposite sides of member 500 can be parallel but offset so as to be asymmetrical. When a member 200 , or a similar member with a male dovetail feature, is received in both of the alternate embodiment member 500 female dovetail features, member 500 becomes a device for joining two parallel but noncoplanar panels 1000 . [0022] In another embodiment of member 500 , either side of member 500 can have more than one female dovetail feature. When a member 200 , or a similar member with a male dovetail feature, is received in, for example, one female dovetail feature on one side of member 500 and two female dovetail features on the opposite side of member 500 , member 500 becomes a device for joining one panel 1000 to two panels 1000 that are parallel but not necessarily coplanar. [0023] In another embodiment of member 500 , one side of member 500 can be constructed without a dovetail feature. The resultant flat surface on one side of the alternate embodiment member 500 can function as a cap to provide a decorative finish or functional appendage to the edge of a partition or wall that emanates from the side of member 500 , or a similar member, having a dovetail feature. Such decorative or functional features can include, for example, millwork, a capital, light fixture, sprinkler head, mister, or electrical outlet. [0024] [0024]FIG. 6 shows an embodiment of one of the members of the present invention. Member 600 is one embodiment of a member that provides, in conjunction with two members 200 , or similar members with male dovetail features, a joining device for two perpendicular panels 1000 . Member 600 also provides a prominent surface 18 that can be manufactured in special-order decorative or functional profiles, finishes, and colors. Member 600 can thus function as a decorative partition or wall corner. Member 600 could be constructed of two mirror-image blocks that are attached with commonly understood fasteners or adhesive so that they share the common surface in the symmetry plane 62 . [0025] In another embodiment of member 600 , one side of member 600 can have more than one female dovetail feature. When a member 200 , or a similar member with a male dovetail feature, is received in, for example, one female dovetail feature on one side of member 600 and two female dovetail features on an adjacent side of member 600 , member 600 becomes a device for joining one panel 1000 perpendicularly to two parallel but noncoplanar panels 1000 . [0026] [0026]FIG. 7 shows one embodiment of one of the members of the present invention. Member 700 is comprised of two or more members, such as members 70 and 71 , that are joined by the receiving of a male dovetail feature on one member by a female dovetail feature on the other member. With only members 70 and 71 , member 700 can function as a vertical center post providing for two, three, or four partitions or walls, or as a horizontal center post providing for both vertical and horizontal partitioning. A member 700 , in conjunction with several members 200 , or similar members having male dovetail features, can thus provide a joining device for any number of parallel and perpendicular panels 1000 . The eight orthogonal surfaces 21 provide member 700 with exposed surfaces that can be stained, painted, or otherwise made decorative or functional. [0027] [0027]FIG. 8 shows one embodiment of one of the members of the present invention. Member 800 is one embodiment of an assembly of several of the present invention's members. A member 100 and a member 400 combine with two members 200 to receive and hold a panel 1000 . In the dovetail slot of member 400 illustrated as being empty in FIG. 8, another member 200 could be received. In that additional member 200 could be received another panel 1000 for a continuation of the panel assembly in a direction 45 degrees from the illustrated panel 1000 . In the FIG. 8 embodiment of member 800 , members 5 are located on opposite sides of panel 1000 . Another embodiment of member 800 could be assembled with members 2 oriented so that members 5 are located on the same side of the illustrated member 1000 . [0028] The members of the present invention can be manufactured in sizes customized to job specifications. A typical partition might require members 100 to have a height of one and three- quarters inches and the narrow opening at the top of the member 100 dovetail feature to have a width sufficient to accommodate a panel 1000 with a width of one inch. [0029] Individual members of the present invention can be any solid material suitable for construction such as metal, plastic, wood, foam, or composite, and can be manufactured in any manner suitable for industry such as machining, extrusion, molding, laser-cutting, or sintering. Surfaces 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , and 21 can be manufactured in special-order decorative or functional profiles, finishes, and colors, but any of the invention's exposed surfaces can be so manufactured. The disclosed embodiment utilizes dovetails to provide the interlocks, but other mortise and tenon designs could be used. A mortise is commonly understood in the building trades to be a hole, slot, groove, square opening, or other cavity in or on one member for receiving a projection on another member for the purpose of joining the two members. [0030] While the present invention has been described in terms of a single preferred embodiment with a few variations, it will be apparent to those skilled in the art that form and detail modifications may be made to that embodiment without departing from the spirit or scope of the invention. For example, any member described as part of the preferred embodiment could have male, instead of female, dovetail features, or vice versa.

A system of interlocking components that provides on-site assembly of frames for holding panels of any solid material or cloth. The frame components can be manufactured in a variety of shapes, and can be cut to accommodate desired panel dimensions and orientations, thus providing customized temporary or permanent partitioning in a timely and cost-effective manner.

This application claims the priority of German patent document 102 60 358.8, filed Dec. 20, 2002 (PCT International Application No. PCT/EP2003/013478, filed Nov. 29, 2003), the disclosure of which is expressly incorporated by reference herein. BACKGROUND AND SUMMARY OF THE INVENTION This invention relates to a method for arc welding with a consumable electrode under a protective gas for joining parts, where one part is made of ductile cast iron and the other part is made of ductile cast iron or steel and the protective gas contains carbon dioxide and/or oxygen in addition to argon. Furthermore, the invention relates to a protective gas mixture for arc welding of ductile cast iron with a consumable electrode which contains carbon dioxide and/or oxygen in addition to argon and also relates to the use of a protective gas mixture which contains carbon dioxide and/or oxygen in addition to argon for joining a part made of ductile cast iron to a part made of ductile cast iron or steel by arc welding with a consumable electrode. Cast iron is smelted as gray pig iron in a blast furnace and produced by remelting. Special features of cast iron include its high carbon and silicon contents. Cast iron typically contains 3 wt % to 4 wt % (percent by weight) carbon and 1 wt % to 3 wt % silicon plus 0.2 wt % to 1 wt % manganese. Cast iron differs fundamentally from steel in its properties and is hard and brittle in comparison with steel. Cast iron is available in various forms, which differ in the properties of the material. The various forms of cast iron are determined by the amounts by weight of the constituents and by the cooling rates after production in a blast furnace. With slow cooling, the dissolved carbon separates out as graphite. This separation of graphite is influenced by nucleating substances and other alloy elements. By adding magnesium or cerium, which is usually in the range of 0.02 wt % to 0.7 wt %, carbon is separated in a spherical form and ductile cast iron is obtained. Ductile cast iron has the highest tensile strength of all types of cast iron and has the greatest breaking strength. The matrix surrounding the carbon has a microstructure, but the type of microstructure depends on the chemical composition of the cast iron, the cooling rates in production and/or a heat treatment of the cast iron. With regard to the matrix, a distinction is made between the ferritic, ferritic-perlitic, perlitic and martensitic microstructures. Welding of ductile cast iron is possible in principle, but in practice there have been some major problems. Welding of ductile cast iron requires special, highly complex welding techniques in order for the material to be weldable and for satisfactory results to be obtained. In particular, prolonged preheating and cooling procedures or heat treatments following the welding process are to be performed, but the heating and cooling rates must be kept very low to prevent cracks and stresses in the material. Cracks and stresses are formed due to the heat input into the material during welding, thus resulting in changes in structure and reshaping of the microstructure of the matrix. The great temperature differences which promote carbon diffusion processes and thus cause structural changes are responsible for this. Due to preheating and cooling procedures as well as the heat treatment, the ductile cast iron can retain the desired structures, while cracks and stresses may be suppressed. Because of these complex procedures, welding of ductile cast iron is possible only at a very low level of productivity and consequently is not used in production. Welding is used only for repairs and servicing of parts made of cast iron. In the welding process itself, only very low welding rates are possible in the range of only a very few kg/h. This is another factor leading to a low productivity. The arc used here is a short arc. Using a short arc does not allow higher melting rates because the short arc leads to defective welds at higher butt welding rates. In the past, argon has generally been used as the protective gas for the electric arc. Various welding wires are suitable as the filling material. In most cases the welding wires used are characterized by a high nickel content, often more than 60 wt %. A welding additive material for protective gas welding of cast iron based on nickel, iron, manganese and carbon is also disclosed in DE 24 37 247, for example. This document also recommends an argon-carbon dioxide mixture or an argon-carbon dioxide-oxygen mixture as the protective gas and it recommends a pulsed arc as the electric arc. These problems are manifested when joining ductile cast iron and also when joining ductile cast iron and steels. These problems are also particularly pronounced when the welding method that is to be used for the weldable steel differs significantly from the welding method for ductile cast iron. Since the welding method for ductile cast iron is a very special method, this is very often the case. A method for joining parts made of cast iron and those made of steel by arc welding using a consumable electrode without preheating the parts is described in DE 36 00 813. According to this publication, the welding is performed by arc welding using a consumable nickel-free electrode under a protective gas in pulsed operation with a two-component or three-component gas mixture consisting of argon, carbon dioxide and/or oxygen. An annealing operation is to be performed downstream from the welding process to suppress unwanted changes in the cast iron with regard to the chemical presence of carbon and the structure. The object of this invention is to provide a method for arc welding using a consumable electrode which permits welding of ductile cast iron to ductile cast iron and ductile cast iron to steel with a high productivity and thus expands the scope of use of ductile cast iron as a material and in particular the use of ductile cast iron as a material for construction parts and manufacturing parts due to the possibility of welded joints with these parts. This object is achieved according to this invention by providing carbon dioxide in a range of 1 to 25 vol % and/or oxygen up to a range of 0.5 to 10 vol % in the protective gas and by having the remainder of the protective gas by volume consist of argon or an argon-helium mixture. Surprisingly a change in structure and a negative effect on the properties of the ductile cast iron are largely suppressed with the inventive protective gas and the result is almost stress-free welds. The development of stresses and cracks in and on the weld is also prevented. This is attributed to the fact that with the method according to this invention, the heat supply by the welding wire into the welding bath is controlled and the heat supply into the ductile cast iron material is controlled. With this controlled heat supply, it is possible to suppress the unwanted diffusion of carbon in the ductile cast iron. This prevents the development of hard and brittle areas in the ductile cast iron which are very susceptible to fracture. Instead of that, the existence of microstructures and thus the strength of the ductile cast iron are preserved. The advantages are manifested with all microstructures that may be present in the ductile cast iron. In the case of ductile cast iron, it is possible with the inventive method to achieve acceptable welding results even when a delayed cooling or downstream heat treatment is omitted. Better results are obtained when the cooling is performed more slowly. If the welding operation is followed by a heat treatment, the best welding results are obtained. In addition, due to the use of carbon dioxide and/or oxygen in the protective gas, the properties of the welding bath and the weld are influenced in a positive sense. Carbon dioxide and oxygen increase the heat input at the welding location and stabilize the arc. These two factors suppress the development of pores. High quality welds are formed. The inventive method is suitable for joining parts made of ductile cast iron as well as for joining parts made of ductile cast iron to parts made of steel. When a part made of ductile cast iron is joined to a part made of steel, unalloyed steel and low-alloy steel in particular are used for the parts made of steel. However, steel parts made of steel having a higher strength, e.g., such as that used in automotive engineering or in crane construction, or parts made of stainless steel may also be used. Welding rates of more than 4 kg/h, in most cases more than 8 kg/h and in advantageous cases even more than 12 kg/h are advantageously achieved. In advantageous exceptional cases, welding rates of more than 15 kg/h are even achieved. The welding rates intended with the inventive method are preferably in the range of 8 kg/h to 15 kg/h. When using a filling wire as the wire electrode, welding rates of more than 12 kg/h are usually achieved, frequently even more than 15 kg/h. A high productivity is ensured with these welding rates. In a possible advantageous embodiment of this invention, two welding wires are used to produce the joint. By using two welding wires, welding rates amounting to approximately double the values given above are achieved. The two welding wires need not have the same wire diameters. The welding rates in welding with two wires are thus advantageously more than 8 kg/h, especially advantageously more than 20 kg/h. Using two welding wires is an especially advantageous variant of the inventive method. However the advantageous embodiments pertain not only to the special welding method with two wires but also to the welding method which uses only one welding wire and is the most widely used method. In an embodiment of this invention, carbon dioxide is added to the protective gas in an amount of 1 vol % to 15 vol %, preferably 2 vol % to 10 vol %. The advantages of the inventive method are especially pronounced with these carbon dioxide amounts. Even when used in amounts by volume at the lower limits, carbon dioxide is sufficiently active to influence the welding process, while on the other hand, even when carbon is used in volume amounts at the upper limits, the possibility of a negative influence on materials and the weld is ruled out. Oxygen is advantageously provided in an amount of 1 vol % to 3 vol % in the protective gas. When using oxygen, essentially the same advantages are manifested as when using carbon. The upper limits for the addition of oxygen, however, are below the volume amounts of carbon because both ductile cast iron and steel are attacked by the highly active oxygen when present in volume amounts higher than those indicated, and this in turn leads to cracks and pores in and on the welds. The advantages of this invention are manifested in particular when nitrogen monoxide is additionally added to the protective gas. The arc is effectively stabilized to an extreme by the addition of nitrogen monoxide, resulting in almost pore-free seams. Furthermore, addition of nitrogen monoxide leads to a definite reduction in the ozone emission formed in arc welding and thus improves the conditions at the job site. In addition, the development of splashes is largely suppressed by the addition of nitrogen monoxide. This facilitates handling of the welding burner in manual welding and facilitates the choice of parameters in automatic welding. The advantage of a stable arc is that there is a uniform transfer of material from the consumable wire electrode into the welding bath. Therefore the development of pores is largely suppressed. This stabilizing effect is manifested with all protective gas mixtures of the inventive method. It is especially advantageous with protective gas mixtures containing helium. Since the addition of helium leads to instabilities in the arc, stabilization must be ensured when helium is added and the arc must be stabilized. This is accomplished according to this invention through the carbon dioxide content and also through the oxygen content. In addition, this is achieved in particular by adding nitrogen monoxide. With this extremely active gas, the advantages are manifested with even a microaddition. With addition of nitrogen monoxide in the percentage range, negative effects are already apparent due to the aggressiveness of nitrogen monoxide. Therefore, the nitrogen monoxide content must remain limited to volume amounts of less than 1%. Nitrogen monoxide is therefore advantageously added as a microadditive, preferably being added in the amount of 10 to 5000 vpm (0.001 to 0.5 vol %) nitrogen monoxide (NO) to the protective gas, preferably 100 to 1000 vpm (0.01 to 0.1 vol %) nitrogen monoxide (NO) added to the protective gas. The advantages of the addition of nitrogen monoxide are achieved with these amounts by volume. However, the disadvantages do not occur. It is particularly advantageous to add helium to the protective gas in amounts of 10 vol % to 60 vol % helium, preferably 20 vol % to 50 vol % helium, especially preferably 30 vol % to 40 vol % helium. The helium preferably replaced volume amounts of argon in the protective gas. However, the use of helium instead of argon, which is much less expensive, increases the cost of the welding operation. The properties of the welding bath are improved as a result of addition of helium and even at high welding speeds the development of pores is suppressed. To achieve a definitely noticeable effect, a helium content of at least 10 vol %, preferably at least 20 vol % should be used. In an advantageous embodiment of this invention, a corona arc is used. To achieve the desired high melting rates, the use of a corona arc is necessary. Using a corona arc normally leads to a high porosity of the weld. However, the corona arc also yields almost pore-free welds by the inventive method. The development of cracks and defects in the ductile cast iron is also suppressed. Furthermore, the arc and the corona arc are stable and can be controlled well with the inventive method. In addition, in an advantageous embodiment of this invention, a free electrode length of at least 15 mm, preferably at least 18 mm is used. When using a filling wire, the free electrode length is advantageously increased even further, and a free electrode length of more than 20 mm, in particular more than 23 mm is to be used with advantage. Thus a much larger free electrode length is selected when welding ductile cast iron and ductile cast iron with steel than when welding steel parts. The increased electrode length in comparison with traditional methods supports the arc stability and control of the arc. Furthermore, such a larger free electrode length improves control of the heat input into the welding wire. Therefore, the heat input into the material of ductile cast iron can be controlled better and changes in structure can be suppressed. A free electrode length in the range of 20 to 30 mm is especially recommended. When choosing a wire feed rate in the upper range of the range from approximately 20 m/min to 30 m/min as mentioned for welding ductile cast iron, the free electrode length may even be 37 mm to 42 mm. In an advantageous embodiment of this invention, the method of pulsed arc welding is used. The advantages of the inventive method are manifested not only when using a corona arc but also with pulsed arc welding. With a consumable electrode, the electrode is in general the welding wire and no other filling materials are used for the weld. The wire feed rate influences the melting rate and the welding speed and thus also the amount of material in the filling layers. When welding ductile cast iron joints and ductile cast iron-steel joints, the wire feed rate to be used is advantageously in the range of 10 to 50 m/min, preferably 15 to 30 m/min. Such wire feed rates make it possible to produce joints economically. In addition, with the wire feed rate it is also necessary to ensure that there is control of the heat supply and welds are formed without bonding errors. Changes in structure in the ductile cast iron must also be suppressed. Preferably solid wire or filling wires are used as the wire electrode. The wire diameter is preferably 0.8 to 2.0 mm, especially 1.0 to 1.6 mm. In principle all welding wires that have previously been used for (repair) welding of ductile cast iron are suitable for the inventive method. The main components of such welding wires are in general iron and nickel, with nickel being present in an amount of more than 30 wt %. The amount of carbon is usually 1 wt %. The welding wire frequently also contains more than 10 wt % manganese. In an advantageous embodiment of this invention, an arc voltage of more than 28 V, preferably in the range of 32 to 45 V is used. In addition, an electric current of 220 A to 500 A, preferably 260 A to 450 A is advantageously adjusted. In an advantageous embodiment, the joint is created from at least two weld layers. The following advantageous procedure is suggested: the first layer of the weld, the so-called root layer, is created by the inventive method. Then a second layer, the so-called filling layer, is applied to this first layer. This is normally done in welding to join thick parts. When welding ductile cast iron, surprisingly a previously unknown advantage has been manifested here: as with any welding, there is a heat input into the welding bath and the material surrounding the welding location via the arc in the case of the second layer. This heat input constitutes a heat treatment for the deeper layer. By applying more than one weld layer, consequently there is essentially a heat treatment of the previous weld layer due to the application of the following weld layer. All weld layers except for the weld layer applied last, thus profit from the advantageous effects of the heat treatment on the weld. It should also be pointed out here that when there are multiple weld layers, individual weld layers, in particular the root layer, can also be applied by TIG welding with a non-consumable electrode. Advantageously at least the parts made of ductile cast iron are preheated to temperature of 200 to 250° C. before the welding operation. This greatly reduces the temperature difference in the ductile cast iron in the vicinity of the welding location and thus contributes toward suppressing structural changes. In an embodiment of the invention, a delayed cooling of the joined parts are alternatively an after-treatment after the welding process is advantageous. A delayed cooling, preferably achieved by embedding the welded parts in diatomaceous earth, is advantageous in comparison with cooling in air, because this improves the properties of the welding joint. As an alternative, the parts that are joined are subjected to an after-treatment to improve the mechanical properties, to reduce stresses and to improve the microstructure of the ductile cast iron. To do so, the parts are heated in an oven at 500 to 900° C. for one to three hours after the welding operation and then are cooled in air. With a downstream heat treatment the welding results are improved in comparison with the procedure with delayed cooling. However, acceptable welding results are also achieved even with cooling in ambient air. An inventive protective gas contains 1 to 25 vol % carbon dioxide and/or 0.5 to 10 vol % oxygen and the remaining volume amount consists of argon or an argon-helium mixture, preferably 2%-10% carbon dioxide, 1%-3% oxygen, nitrogen monoxide, and 30%-40% helium. The advantages of the inventive protective gas mixture consequently correspond to the advantages of the inventive method. When using the inventive protective gas mixture for joining parts made of ductile cast iron and ductile cast iron and parts of made of ductile cast iron and steel, the advantages of the inventive method are especially pronounced. BACKGROUND AND DESCRIPTION OF THE DRAWING FIG. 1 is a graph illustrating a hardness profile over a width of a joint welded in accordance with an embodiment of the present invention. This invention will now be explained in greater detail below on the basis of six exemplary embodiments in particularly advantageous embodiments and on the basis of FIG. 1 . DETAILED DESCRIPTION In a first exemplary embodiment, two parts made of ductile cast iron are welded together. The joint is in the form of a V-weld. Before the actual welding process, the two parts are heated to 200° C. In the subsequent MAG welding, corona arc welding is used as the arc mode. The arc voltage is 44 V and the current is 300 A. The wire feed rate here is set at 18 m/min. A solid wire is used, its main components being iron and nickel with a carbon content of less than 1 wt %. The wire diameter is 1.2 mm. For welding, a free electrode length of 25 mm, which is large in comparison with the usual values, is established. According to this invention, a gas mixture of 8 vol % carbon dioxide with the remainder of the volume comprises of argon is used as the protective gas. In addition, the protective gas may contain 275 vpm (0.0275 vol %) nitrogen monoxide. No after-treatment is necessary, but it is advisable to embed the joined parts in diatomaceous earth for cooling immediately after welding until they reach approximately ambient temperature. This yields a tensile strength of 250 MPa and an elongation of 2%. In the second exemplary embodiment, two parts made of ductile cast iron are joined with a throat seam. The preheating temperature is 250° C. The following settings are selected with MAG welding: corona arc, 45 V arc voltage and 450 A current, 16 m/min wire feed rate, 1.6 mm wire diameter, 28 mm free electrode length. The inventive protective gas contains 10 vol % carbon dioxide, 3 vol % oxygen and argon. In addition to this protective gas mixture, the advantages of this invention are also achieved with a mixture of 10 vol % carbon dioxide, 3 vol % oxygen, 30 vol % helium with the remainder being argon. A protective gas mixture of 15 vol % carbon dioxide in argon and a mixture of 5 vol % oxygen in argon is also possible. Joining parts made of ductile cast iron and steel is explained in the third exemplary embodiment. The two parts or at least the part made of ductile cast iron is heated to 230° C. before the welding operation. The following parameters are selected for MAG welding: corona arc, 37 V arc voltage and 280 A current, 22 m/min wire feed rate, 1.0 mm wire diameter, 22 mm free electrode length. The throat seam may be designed to be in horizontal position or in PB position. The following protective gas mixture is used: 8 vol % carbon dioxide, 20 vol % helium and the remainder argon. Instead of the carbon dioxide, an amount of 4 vol % oxygen is also possible. An after-treatment recommended to improve the microstructure involves heating the welded parts for two hours at 700° C. and then cooling in air. In the fourth exemplary embodiment, again a part made of ductile cast iron is to be joined with a part made of steel. In the following protective gas mixtures, the inventive advantages are manifested in a particularly pronounced manner: in the case of a mixture of 5 vol % carbon dioxide, 1000 vpm nitrogen monoxide, 40 vol % helium and the remainder argon as well as with a mixture of 3 vol % oxygen, 200 vpm nitrogen monoxide, 20 vol % helium and the remainder argon. The other welding parameters correspond to those of the exemplary embodiments mentioned above. The free electrode length is selected in deviation from that, amounting to between 28 mm and 32 mm here. In the fifth exemplary embodiment, a plate of ductile cast iron is joined to a plate of low alloy steel with a V-weld. The plates have a thickness of 15 mm. They are preheated to 250° C. Two weld layers are created. A nickel-based solid wire with a wire diameter of 1.2 mm is used. The welding speed is 28 cm/min. A mixture of 2 vol % carbon dioxide, 30 vol % helium, 275 vpm nitrogen monoxide and the remainder argon is used as the protective gas. The welding parameters for the first layer are: arc voltage 33.3 V, arc current 268 A, wire feed rate 16.1 m/min, free electrode length 37 mm. With these welding parameters, a melting rate of 8.3 kg/h is achieved. For the second layer, the following parameters are used: arc voltage 41.5 V, arc current 308 A, wire feed rate 18 m/min, free electrode length 22 mm. The melting rate here is 9.2 kg/h. The result is a V seam of excellent quality with a tensile strength of 300 MPa and with an elongation of 2%. If instead of the aforementioned protective gas mixture, a gas mixture of 2 vol % carbon dioxide, 275 vpm nitrogen monoxide and the remainder argon is used, this also yields a high quality weld although the tensile strength is lower than that obtained with the helium-based protective gas mixture. FIG. 1 shows the result of the hardness test of the weld produced with the protective gas mixture mentioned first. The abscissa shows the hardness of the steel plate, plotted on the ordinate, at different locations from left toward the right (in mm) across a weld and into the area of the ductile cast iron plate. The area of the weld is indicated by the two vertical bars. It can be seen here that the hardness plotted on the ordinate changes in the area of the weld but the change is very minor. Consequently this is a high quality weld. In the sixth exemplary embodiment, two plates 15 mm thick made of ductile cast iron are joined together. The plates are preheated to 250° C. The welding parameters include: arc voltage 38 V, arc current 453 A, wire feed rate 27 m/min, wire diameter 1.2 mm, free electrode length 30 mm. The welding speed is 28.5 cm/min and the melting rate is 14 kg/h. The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.

A method for joining components made from ductile cast iron and made from ductile cast iron and steel, by arc welding with fusible electrodes under a gas blanket. The gas blanket comprises, in addition to argon, 1 to 25 vol. % carbon dioxide and/or 0.5 to 10 vol. % oxygen. The gas blanket can also comprise nitrogen monoxide. Said method permits high welding speeds and hence a high productivity. The joint quality can be further advantageously improved by means of a pre-heating of the components and a slow cooling or a post-treatment.

BACKGROUND OF THE INVENTION 1. Technical Field of the Invention The invention relates to the field of positioning devices, i.e. of finely positionable actuators as for example used for scanning tunnelling microscopes and other scanning microscopes, so-called scanning probe microscopes. In particular, the invention relates to the construction of such a multiaxis actuator which can carry out three-dimensional movements of a sensor or a scanning tip with high regulating accuracy while being of comparatively robust and compact design. Furthermore, the invention relates to a measuring head for a scanning probe microscope comprising such an actuator. Appropriate integration of the actuator results in a robust measuring head which is simple in operation and which has advantages when compared to the state of the art. 2. State of the Art In scanning probe microscopy, positioning of the scanning tip has been a somewhat problematic task from the very start because such positioning needs to be at the highest possible resolution while maintaining as large a regulating range as possible. In addition, good repeatability, i.e. adjustability as far as possible free of any hysteresis, is required, as is little mass, if for no other reason than that of low energy consumption. When the desire for rational, economical production of a respective measuring head is taken into account as well, it becomes evident why a host of different approaches to solving this problem of positioning scanning tips have been made. Piezo actuators are in use as are for example electromagnetic or electrostatic actuator elements for the actuators. Many of today's scanning probe microscopes (SPMs) use piezo actuators for the necessary fine positioning which takes place in the micrometer to sub-nanometer range. But there are also other approaches as will be shown below. However advantageous piezo actuators are in several respects, they also have a number of disadvantages, among them in particular the expensive electrical control devices and the comparatively high operating voltages, often in the 100 V or 1000 V range, with the need for respective protective devices. Furthermore, linearity is not always achieved as desired and might have to be improved by applying control technology. In addition, hysteresis can be a problem which is difficult to solve. Furthermore, extended regulating distances which after all are almost always desirable, can only be realized with relatively large arrangements. Nonetheless, due to their comparatively robust design and good value, piezo actuators have established a firm position in the market. While other attempts at solving the problem have always been pursued, e.g. magnetostrictive, electrostrictive or electrostatic approaches, so far they do not seem to be suitable for large regulating distances, i.e. actuator regulating distances around or in excess of 50 μm. This has kept a limit on possible applications and therefore also on the interest in such actuators. By contrast, electromagnetic actuators, often referred to as voice coil arrangements, have attracted considerable interest right from the start. They are used in a host of different applications, above all outside the area of scanning probe microscopy. One such example, from the area of consumer electronics, are CD reading heads which are positioned by multidimensional actuators. Electromagnetic actuators are inherently quite linear, they can cover comparatively large regulating distances up to the mm range, and they can be operated at low voltage. Often a voice coil arrangement with stationary permanent magnet and movable coil is used but other arrangements are also known. Such an arrangement for use in a scanning probe microscope (or a respective memory) is described by G. Binnig et al in PCT patent application WO 96/07074: “Fine positioning apparatus with atomic resolution”. This arrangement provides for two inductive actuator units with a positioning accuracy of better than 1 nm. A mechanical damping device acts as a brake and, together with a special mechanical arrangement, as a variable step-down device of the electromagnetic actuator. While this is intended to improve the positioning accuracy of the entire device, it renders the overall design relatively expensive and heavy. This significantly limits the range of possible applications. Nor is an arrangement in the form shown conducive to economical production. For example, the electrical cables to the movable voice coils also need to be movable which can be problematic for production as well as for reliability. A further approach was described by S. T. Smith et al in the journal “Rev. Sci. Instruments”, vol. 65, no. 4 April 1994, on pages 910 ff., entitled “A simple two-axis ultraprecision actuator”. It shows an actuator comprising two actuator units, one of which is used for translatory positioning, the other for angular positioning. Reportedly, translatory distances of 80 μm have been achieved, with angular ranges of 3.6 mrad being achieved at a positioning accuracy of 0.6 nrad. While this actuator only covers two axes, which would limit its application possibilities, it nevertheless provides a pointer as to what an actuator or relatively simple design might look like. But it must not be overlooked that the actuator shown by S. T. Smith, according to the presentation in the above-mentioned article really only seems suitable for illustrating the theory and general function. It is not well-developed from a production-technology point of view, indeed production-technology considerations do not seem to have featured at all in its design. At any rate it could hardly be considered a model for a robust actuator which is relatively simple to produce. Even more importantly, there is no description as to how the actuator described might be used in three dimensions. A further, quite interesting approach is shown by R. Garcia Cantu et al in their article “Inductoscanner Tunneling Microscope”, in Surface Science 181, pp. 216-221, Elsevier Science Publishers B.V. 1997. The actuator for a scanning tunnelling microscope described comprises a pair of diametrically opposed voice-coil actuator elements with a support, with the scanning tip extending between said actuator elements which are advantageously operated at low voltage. Suspension is via metal membranes, similar to that in an aneroid barometer. The authors do not however demonstrate resolution in the sub-nm range as required for the desired application and thus do not meet the objective set by the invention. Moreover, the selected arrangement of the opposing voice coil actuators appears to be somewhat voluminous and hardly suitable for economical production. In addition, large volume usually results in low self resonance which is not always desirable, and substantial mass and the associated large working surface almost always means a high susceptibility to external interference. SUMMARY OF THE INVENTION As can be seen from the above, it is the object of the invention to create a three-dimensionally controllable electromagnetic actuator, in particular for scanning probe microscopes, with said actuator being of comparatively simple and robust construction with regulating distances as large as possible—preferably in the 100 μm range—while at the same time providing good positioning accuracy —preferably in the sub-nm range—and high linearity as far as possible without external feedback, especially without mechanical feedback. In addition, the arrangement should be compact and as simple as possible to produce. This rather complex object is met in principle relatively simply by the invention by the arrangement of preferably three electromagnetic actuator units arranged in one plane and/or being essentially identical, said actuator units being connected to a rigid fulcrum structure supporting the scanning tip such that said fulcrum structure, depending on the activation of the actuator units, can be tilted on any desired rotary axis in said plane and/or can be moved in a translatory way essentially perpendicularly to said plane, as a result of which the scanning tip, which is situated outside said plane, can be moved in space quasi in any way desired. It would be advantageous, but this is not a condition, if the three actuator units were to act in the same direction of action and in addition, if they were positioned in a suitable plane. In this way, the spring provided for each actuator unit could be advantageously configured as a part of a diaphragm spring shared by all actuator units, thus reducing construction expenditure. Below, further advantageous embodiments are shown in the description of an embodiment and in the claims. BRIEF DESCRIPTION OF THE DRAWINGS One embodiment of the invention is described in conjunction with the drawings, as follows: FIG. 1 is an overall view of an actuator according to the invention; FIG. 2 shows details of the actuator shown in FIG. 1; FIG. 3 is an example of an electrical control circuit. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS List of References FIG. 1 1 Housing 2 Fulcrum frame 3 Tip holder 4 Scanning tip 5 a, 5 b, 5 c Actuator unit FIG. 2 (in addition) 6 Diaphragm spring 7 a, 7 b, 7 c Permanent magnet 8 a, 8 b, 8 c Spring element 9 a, 9 b, 9 c Coil FIG. 3 (in addition) 10 a, 10 b, 10 c U/I transducer 11 a, 11 b, 11 c Adding device 12 Amplifier group Vx, Vy, Vz Input terminal FIG. 1 is an overall view showing the essential components of the preferred embodiment of the actuator according to the invention. In or on a housing 1 , three actuator units 5 a to 5 c are essentially arranged in one plane, with the movable parts (shown in more detail in FIG. 2) of said actuator units 5 a to 5 c being rigidly connected to a fulcrum frame 2 . At the top of said fulcrum frame 2 and connected to it, there is a tip holder 3 which tapers off to a scanning tip 4 . According to the object of the invention, this scanning tip is to be positioned at high accuracy in all three spatial directions on the workpiece (not shown) to be scanned. This positioning takes place by tilting and/or sliding the fulcrum frame 2 by means of the actuator units 5 a to 5 c , each one of which is individually controllable electrically. If for example the two actuator units 5 a and 5 c are blocked and only the actuator unit 5 b is driven, then tilting of the fulcrum frame 2 around an axis 5 a - 5 c takes place. As a result of this, the scanning tip 4 describes an arc of a circle centred on said axis 5 a - 5 c . If all three actuator units are driven equally, the fulcrum frames 2 and the scanning tip 4 describe a translatory movement perpendicular to the surface of the housing, or to the plane of the three actuator units. It becomes obvious that by suitable driving of the three actuator units, within certain limits any desired tilting movement of the fulcrum frame can be carried out around almost any desired axis of rotation. The above-mentioned translatory movement can be added to this. To carry out such movement, it is merely necessary to calculate and co-ordinate the amounts, i.e. the deflections of the actuator units. This will be explained below by way of an example. FIG. 2 shows in particular in more detail the actuator units 5 a to 5 c , with fulcrum frame 2 , tip holder 3 and scanning tip 4 not shown. The housing 1 is capped by a diaphragm spring 6 which in those positions, where there is an actuator unit 5 a to 5 c , is configured as a spring element 8 a to 8 c . Said spring elements can, for example, be in the form of spiral slots in the diaphragm spring 6 . At each of these spring elements 8 a to 8 c , a permanent magnet 7 a to 7 c is attached which acts in conjunction with a coil 9 a to 9 c arranged in the housing 1 . By electrically driving each of these coils, exactly controllable excursion or deflection of the permanent magnet takes place (and thus the movement of the fulcrum frame, not shown in FIG. 2, as explained above in the context of FIG. 1 ). According to a preferred embodiment, the actuator units are arranged and operated such that the scanning tip 4 can be moved in three spatial directions orthogonal to each other. The spatial arrangement of the actuator units 5 a to 5 c and the mix ratio of the movement contributions made by said actuator units determine the orthogonality of the scanning tip movement generated. From a spatial point of view, for example, an arrangement of the three actuator units at the corner points of an isosceles triangle has been shown to be particularly suitable. Fine adjustment can take place either mechanically by respective adjustment devices on two or all three actuator units, or by electrical or electronic means in that the mix ratio of the currents through the coils 9 a to 9 c is balanced accordingly. It is also possible to combine these two methods of mechanical and electrical adjustment. The following is one example of an orthogonal arrangement. At a distance of 12 mm between the two actuator units 5 a and 5 c , the perpendicular distance to it of the scanning tip 4 is 6 mm. Movement of the scanning tip 4 parallel to a plane extending through 5 a - 5 c and perpendicular to the diaphragm spring 6 , is now for example generated by a “full” deflection of one of the actuator units 5 a or 5 c (the respective other actuator unit remains motionless) and “half” a deflection of the actuator unit 5 b . As an alternative, actuator unit 5 b can be held in place while the two actuator units 5 a and 5 c can be moved in opposite direction around the same deflections. Movement of the scanning tip 4 parallel to a plane extending through said scanning tip itself and 5 b and perpendicular to the diaphragm spring 6 is for example generated by a particular “full deflection” of the actuator unit 5 b and a partial deflection, for example a “half” deflection of each of the actuator units 5 a and 5 c . It becomes obvious that the ratio of deflections of the three actuator units 5 a to 5 c permits precise control of the scanning tip 4 . If the three actuator units 5 a to 5 c are driven in a quasi parallel way, such that they carry out deflections of the same size, then the diaphragm spring 6 moves up or down parallel to itself and with it the scanning tip 4 . Of particular interest is the damping action which is generally required, especially in the case of scanning microscopes. Here too, the embodiment according to the invention is particularly advantageous. By using the design of a practically closed housing, it is possible to use a liquid viscous damping medium in the housing 1 , said damping medium being used to mechanically dampen the oscillations of the diaphragm spring 6 . Damping polymers could also be considered for this task. As an alternative or in addition, active electrical damping can take place by designing the electrical controls accordingly. Controls suitable for this are known in principle, e.g. from electro-acoustics, for damping the self resonance of loudspeakers. The necessary adaptations required in the present case should not pose any difficulties to persons skilled in the art. So as to provide an impression of the physical size of an embodiment and the electrical values, a few details and exemplary dimensions are provided below, which can of course be changed almost without limits by a person skilled in the art. In an arrangement made for laboratory purposes, the housing 1 is fade of metal, with the dimensions LWH being approx. 20 mm×18 mm×6 mm. The three actuator units 5 a to 5 c are constructed identically, being arranged at the corner points of an isosceles (almost equilateral) triangle with an edge width of 11 and 12 mm. The size of the metal fulcrum frame 2 corresponds to these measures; its shape can be as shown in FIG. 1 but it is practically irrelevant except for the distance between the scanning tip 4 and the diaphragm spring 6 (described in detail later). Said distance is 6 mm. At the open side of the housing 1 , a non-magnetic diaphragm spring 6 , preferably metallic, is arranged. Within the housing, three coils 9 a to 9 c forming part of the actuator units 5 a to 5 c are attached, with each of said coils carrying several thousand windings on a coil body measuring a few mm in diameter. The coil may either be without a core (air-core coil) or with a core made of magnetic material, as desired. If a core is used, the effectiveness of the coil is improved but at the same time certain non-linearity is introduced. Opposite each coil there is a permanent magnet 7 a to 7 c , each of which is attached to a spring element 8 a to 8 c in said diaphragm spring 6 . The permanent magnets 7 a to 7 c are of cylindrical shape, with a height of a few mm and a comparable diameter. In the rest position without any excursion, the distance between the permanent magnets 7 a to 7 c and the coils 9 a to 9 c is less than 1 mm. The operating voltage of the actuator units 5 a to 5 c is +/−12 V. The housing 1 can be closed off by a housing lid (not shown in the figures) which comprises only a comparatively small aperture for the tip holder 3 . In this way, exterior interference, for example acoustic or magnetic interference, is reduced or entirely suppressed; it can then not cause any distortion of the measurements. Furthermore, such a housing lid can serve as a mechanical end stop for the moving parts, in particular for the diaphragm spring 6 , thus preventing damage to the arrangement as a result of improper handling or undesired mechanical influences. FIG. 3 is a diagrammatic representation of the electrical control for driving the three actuator units. The electrical control is described based on the coils 9 a to 9 c shown in FIG. 2, of the actuator units. The coils are connected to the mass and at the same time each of the 1 s coils 9 a to 9 c is fed by a voltage/current transformer (U/I transducer) 10 a to 10 c because of the temperature dependence of the coil resistance and the inevitable heating up of each coil during operation. The input voltages required for these voltage/current transducers are derived from the three adding devices 11 a to 11 c , with each of said adding devices being supplied with three input voltages (to be added) by the amplifier system 12 . In the example shown, the amplifier system 12 comprises six controllable voltage amplifiers G 1 to G 6 which are fed by three input voltages present at the input terminals Vx, Vy and Vz. As shown, each of the adding devices 11 a to 11 c is directly connected to one of the input terminals and, via an amplifier each, to the two other input terminals. In this way, any desired voltage mix ratios can be generated at the inputs of the three voltage/current transducers 10 a to 10 c and thus the coils 9 a to 9 c of the three actuator units can be selected as desired. Of course this simple and robust circuit can be modified to create the same or a similar effect. This should pose no problem to a person versed in the art. This relative simplicity and robustness both from a mechanical and electrical point of view obviously renders the arrangement according to the invention suitable also for fine positioning in fields other than scanning microscopy. For example in robot-controlled production, similarly precise movement controls are often required, for example in micro-mechanics. In the field of medical operations, too, there are tasks for which the solution according to the invention appears applicable. A person versed in the art should not find it difficult to modify the embodiment which has been described in the context of a microscope measuring head, such that it is suitable for similar fine positioning in other areas and thus leads to the same advantages as described in the above application. For example, it could be imagined that the arrangement for a microscope is reversed so that the specimen to be examined is arranged on the actuator while the probe or scanning tip is arranged so as to be stationary. Such variations are to be encompassed by the present invention.

Finely adjustable actuators are used for positioning a sensor or a scanning tip, especially for scanning tunnelling microscopes and other scanning microscopes, i.e. scanning probe microscopes. The invention relates to the construction of such an actuator which can carry out three-dimensional movements of a scanning tip with high regulating accuracy while being of robust and compact design. This is achieved by a sensible arrangement of a plural number of electromagnetic actuator elements acting on a common rigid sensor carrier. The invention provides a robust and relatively simple solution for positioning the scanning tip; an important and problematic task in scanning probe microscopy and in related fields. It permits positioning at high resolution as well as with a relatively long regulating range. Further advantages include good repetition accuracy and little mass which reduces both energy consumption and interference.

FIELD The present disclosure relates to border and perimeter monitoring systems and applications, and more particularly to a system and method that use electromagnetic wave signals to generate images of a border or perimeter area that can be compared to detect the presence and movement of individuals or objects in the geographic area being monitored. BACKGROUND The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. Presently there is a growing interest in monitoring border areas, for example, the geographic border between the United States and Mexico. Cost effective monitoring of the perimeter of an important structure, for example a military facility, a bridge, power generating station, water treatment station, etc., is also increasing in interest. Presently available monitoring systems have typically been somewhat costly to implement and/or to operate, or have suffered from one or more other drawbacks. For example, monitoring operations performed by individuals traversing a region by ground vehicles or by airborne vehicles can be quite costly. Attempts at reducing the operating or implementation costs for a monitoring station have sometimes involved the use of a plurality of terrestrially mounted cameras. However, such cameras often need to be mounted on towers or elevated platforms, and once mounted, may be difficult to inspect and/or repair. For monitoring large geographic areas, sometimes hundreds or more cameras are required to fully image the area in question. And the optical image provided by a camera can be significantly adversely affected by environmental conditions such as rain, fog, snow, etc. Other attempts at implementing monitoring systems have involved obtaining image data from one or more cameras or optical sensors located on a flying airborne platform. The electronic image data obtained by equipment on the airborne mobile platform is relayed via RF signals, or via a transponded satellite link, to electronic equipment at a ground based control station. The image data is processed at the ground station and used by individuals charged with managing the monitoring operation. As will be appreciated, this type of system involves a very significant cost, both in its initial implementation and in its on-going operations. Typically large amounts of data need to be up-linked to the selected satellite and then down-linked from the satellite to the ground station. The use of a satellite link adds significant cost and complexity to such a system, not to mention the cost of the complex electronics that must be carried on board the airborne platform. SUMMARY In one aspect the present disclosure relates to a method for monitoring an area. The method may comprise: transmitting a first electromagnetic wave signal from a mobile platform moving over a ground surface, toward the ground surface; using a receiver located remote from the mobile platform to receive the first electromagnetic wave signal after the first electromagnetic wave signal is reflected from the ground surface; processing the first electromagnetic wave signal to form a first synthetic aperture radar (SAR) image; subsequently using the receiver to receive a second electromagnetic wave signal transmitted from the mobile platform and reflected from the ground surface, at a time subsequent to transmission of the first electromagnetic wave signal; processing the second electromagnetic wave signal to obtain a second SAR image; and analyzing the first and second SAR images to determine areas of non-correlation between the images. In another aspect the present disclosure relates to a method for monitoring a geographic area. The method may comprise: transmitting a first electromagnetic wave signal from an airborne mobile platform flying over a ground surface, toward the ground surface; using a receiver located remote from the airborne mobile platform to receive the first electromagnetic wave signal after the first electromagnetic wave signal is reflected from the ground surface; processing the first electromagnetic wave signal to form a first synthetic aperture radar (SAR) image; subsequently using the receiver to receive a second electromagnetic wave signal transmitted from the airborne mobile platform at a time subsequent to transmission of the first electromagnetic wave signal, and after the second electromagnetic wave signal has been reflected from the ground surface; processing the second electromagnetic wave signal to obtain a second SAR image; and analyzing the first and second SAR images to determine areas of non-correlation between the SAR images; and using the areas of non-correlation to form a two dimensional change map of a predetermined geographic region, the two dimensional change map highlighting differences between the two SAR images to make the differences visually perceptible to an individual. In another aspect the present disclosure relates to a system for monitoring an area. The system may comprise: a mobile platform; an electromagnetic wave signal transmitter supported on the mobile platform for transmitting electromagnetic wave signals toward a ground surface over which the mobile platform is traversing; a receiver located remote from said mobile platform to sequentially receive first and second ones of said electromagnetic wave signals transmitted from said transmitter after said first and second electromagnetic wave signals have reflected from said ground surface within a predetermined geographic region over which said mobile platform is traversing; and a processor adapted to process the first and second electromagnetic wave signals to form first and second synthetic aperture radar (SAR) images, and to analyze the images to determine areas of non-correlation between the images within the predetermined region of the ground surface. It will be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. FIG. 1 is a block diagram of a system in accordance with one embodiment of the present disclosure; FIG. 2 is a block diagram of the processor shown in FIG. 1 ; and FIG. 3 is a flowchart of operations performed by the system in carrying out a monitoring operation. DETAILED DESCRIPTION The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. Referring to FIG. 1 , there is shown a bistatic monitoring system 10 in accordance with one embodiment of the present disclosure. The system 10 includes a mobile platform 12 , which in this example is shown as an unmanned air vehicle (hereinafter “UAV” 12 ) having an on-board electronics system 14 that includes a radio frequency (RF) transmitter 16 and an antenna 18 . The RF transmitter 16 generates electronic signals that are transmitted as electromagnetic wave (hereinafter simply “RF”) signals 20 a , 20 b and 20 c towards a ground surface 22 as the UAV flies over a predetermined geographic area or region 23 . The RF signals 20 a - 20 c are transmitted sequentially as the UAV 12 makes a plurality of passes over the same predetermined geographic area 23 . Thus, there will be some tangible degree of time separation between when the signals 20 a - 20 c are generated. For example, the signals 20 a , 20 b and 20 c may be separated in time by minutes, hours, days, weeks or even months. It is expected that in most applications, the UAV 12 will pass over a predetermined region a .plurality of times, and that successive passes will be separated most typically by hours or days. The RF signals 20 a - 20 c generated by the RF transmitter 16 of the UAV 12 are typically selected to be within the frequency band of about 200 MHz - 30GHz. While the UAV 12 is shown as forming the mobile platform, it be appreciated that a land vehicle may potentially also be used for transmitting the RF signals 20 a - 20 c . For example, a land vehicle could be driven along an elevated ridge adjacent to a canyon or valley, with an on-board antenna directing RF signals towards the floor of the canyon or valley. The reflected signals could then be received by a terrestrial based receiver located near the canyon or valley floor, or possibly on a ridge on the opposite side of the canyon or valley. The system 10 could also be implemented in a marine application. For example, a ship could be used to transmit electromagnetic wave signals that are reflected off of water, picked up by a different ship or land-based monitoring station, and used to look for other vessels in a predetermined portion of an ocean or sea. Still further, potentially a space application could be implemented where a transmitter is located on a space vehicle, for example on a satellite. Referring further to FIG. 1 , the system 10 further includes a terrestrial based monitoring station 24 , which will be referred to for convenience simply as the “ground station” 24 . The ground station 24 includes an antenna 26 , an electromagnetic wave signal receiver 28 (hereinafter simply “RF receiver” 28 ), a processor 30 , a data storage system 32 that forms an archive for synthetic aperture radar (SAR) images generated by the processor 30 (hereinafter simply the “SAR image archive” 32 ), and a display system 34 . The antenna 26 preferably is mounted on a tower 26 a and receives the RF signals 20 a - 20 c after they have been reflected from the ground surface 22 . The signals output from the antenna 26 are input to the RF receiver 28 which generates electrical signals corresponding to the received RF signals, which are input to the processor 30 . The electrical signals are used by the processor 30 to generate a synthetic aperture radar image of the predetermined geographic area 23 that is traversed by the UAV 12 which is stored in the SAR image archive 32 . It will also be appreciated that the components of the ground station 24 need not be co-located at a common location, as long as they are able to communicate (either via wired or wireless links). For example, there could be several towers with antennas monitoring different regions of a border, and a common ground station processing all of the data received from all of the antennas. Each SAR image stored in the SAR image archive 32 represents a complex-valued image made up of a large plurality of pixels, typically on the order of millions pixels. Each pixel will have an associated magnitude and phase. On each pass by the UAV 12 over the predetermined geographic area 23 , the processor 30 uses the reflected RF signals received by the antenna 26 to generate an SAR image of the predetermined geographic area 23 that is traversed during that particular pass, that is then stored in the SAR image archive 32 . Thus, after two passes by the UAV 12 over the area 23 , the processor 30 will have created and stored two SAR images, after three passes the processor will have created and stored three SAR images, and so forth. The geometry of the two flight paths is chosen to ensure coherency between the two data collections. It will be appreciated, however, that one could create more than one SAR image per pass. Multiple SAR images per pass might improve the quality of the SAR images obtained. Referring to FIG. 2 , the processor 30 includes an image registration subsystem 36 that is used to “register” any two images, and most typically two successively created SAR images. By “register” it is meant that the two images are mathematically warped to correct for residual geometric differences and to align surface features of the two SAR images. A correlation analysis subsystem 38 coherently analyzes the two selected images, pixel-by-pixel, in phase and in magnitude, to determine regions of pixels that do not correlate, and to identify those regions that do correlate. The correlation regions are chosen to be small enough to provide sufficient spatial resolution of the changes, but large enough to contain enough pixels to reduce the measurement noise. Typically, a correlation region may by 3×3 to 8×8 pixels, depending on the sensor and data characteristics. The correlating and non-correlating pixel regions are then used to form a high resolution, two-dimensional “change” map in which the non-correlating regions are highlighted, for example darkened, to make them more easily visually perceptible. By “change” map, it is meant a map of the predetermined geographic area 23 , created from two SAR images, that has any changes between the two images, such as the presence or absence of vehicles, individuals, or geographic features, highlighted to make them easily visually perceptible. The resulting two-dimensional change map is then displayed on the display system 34 . The display system 34 may be a CRT or LCD display, or any other form of display suitable for displaying graphical images. Referring now to FIG. 3 , a flowchart 100 is shown to illustrate various operations that are performed by the system 10 shown in FIG. 1 . Initially, at operation 102 the UAV 12 makes two or more passes over the predetermined geographic region area 23 and generates RF signals (such as signals 20 a - 20 c ) that are directed toward the ground surface 22 , and reflected from the ground surface. At operation 104 the ground station 24 receives the reflected RF signals using antenna 26 . At operation 106 the RF receiver 28 typically captures the RF signals provided by the antenna 26 and encodes them in a digital format, and provides its output to the processor 30 . At operation 108 the processor creates a plurality of SAR images, one associated with each pass of the UAV 12 over the predetermined geographic area 23 . At operation 110 the processor 30 stores each SAR image in the SAR image archive 32 . At operation 112 the processor 30 accesses the SAR image archive 32 and obtains two (or potentially more) of the SAR images At operation 114 the processor 30 registers the two SAR images. At operation 116 the processor 30 performs a pixel-by-pixel comparison of the two SAR images to determine corresponding pixel regions from the two SAR images that do not correlate. At operation 118 the processor 30 uses the information obtained from its analysis to construct the high resolution, two-dimensional change map of the predetermined geographic region 23 . At operation 120 the processor 30 transmits the two-dimensional change map to the display system 34 for display and subsequent analysis. The subsequent analysis may be performed by an individual or by an automated algorithm adapted to digitally analyze the change map. The system 10 and method of the present disclosure provides the significant advantage that no separate communication signal is needed from the UAV 12 to any external subsystem or transponder in order to pass large amounts of data. This significantly simplifies the acquisition of information from the UAV 12 and can significantly reduce the overall cost of implementing and operating a monitoring system. In particular, since the system 10 is a bistatic system, it does not require a receiver or mission data communication system to be located on-board the UAV 12 , which reduces cost associated with outfitting the UAV for use with the system 10 . This also reduces the weight of the UAV 12 and can contribute to longer in-flight operational times for the UAV. Unlike a ground-based only system (e.g., using fixed, ground-based cameras or sensors), the high resolution, two-dimensional change map produced by the system 10 is much better able to resolve false alarms such as blowing vegetation and animal activity. The system 10 and method of the present disclosure is especially well suited for monitoring perimeter areas, such as geographic borders between countries or the perimeter of a facility (e.g., power station, water treatment facility, etc.). While various embodiments have been described, those skilled in the art will recognize modifications or variations which might be made without departing from the present disclosure. The examples illustrate the various embodiments and are not intended to limit the present disclosure. Therefore, the description and claims should be interpreted liberally with only such limitation as is necessary in view of the pertinent prior art.

A method for monitoring an area that involves transmitting a first electromagnetic wave signal from a mobile platform moving over a ground surface, toward the ground surface. A receiver is used that is located remote from the mobile platform to receive the first electromagnetic wave signal after the signal is reflected from the ground surface. The first electromagnetic wave signal is processed to form a first synthetic aperture radar (SAR) image. Subsequently the receiver is used to receive a second electromagnetic wave signal transmitted from the mobile platform at a time subsequent to transmission of the first electromagnetic wave signal. The second electromagnetic wave signal is then processed to obtain a second SAR image. The first and second SAR images are then coherently analyzed to determine areas of non-correlation between the images.

CROSS-REFERENCE TO RELATED APPLICATION This application claims the benefit of Korean Patent Application No. 10-2008-0017859, filed on Feb. 27, 2008, which is hereby incorporated by reference in its entirety as if fully set forth herein. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laundry machine, and more particularly, to a laundry machine constructed in a structure in which a cabinet and a subcabinet are easily coupled to and separated from each other. 2. Discussion of the Related Art Generally, based on a laundry loading method, a laundry machine may be classified as a top loading type laundry machine or a front loading type laundry machine. In recent years, there has been developed a laundry machine equipped with a sub cabinet that is capable of keeping laundry to be treated in addition to a cabinet. FIG. 1 is a perspective view illustrating a laundry machine 1 including a sub cabinet 20 . In the laundry machine 1 , the sub cabinet 20 is normally located below a cabinet 10 . The cabinet 10 and the sub cabinet 20 may be coupled to each other by connection devices. SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a laundry machine that substantially obviates one or more problems due to limitations and disadvantages of the related art. An object of the present invention is to provide a laundry machine which does not need additional connection devices when a cabinet and a sub cabinet are connected to each other. Another object of the present invention is to provide a laundry machine constructed in a structure in which a cabinet and a subcabinet are easily coupled to and separated from each other. Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a laundry machine includes a cabinet defining a first receiving space to receive laundry to be treated, a plurality of legs each of which comprises a leg head located at an installation surface and a leg body configured to connect the leg head to the cabinet, a sub cabinet defining a second receiving space having a volume less than the first receiving space, the sub cabinet being coupled to a bottom of the cabinet, and a plurality of coupling members configured to detachably couple the sub cabinet to the cabinet. Each of the coupling members may include a leg bracket coupled to a bottom of the cabinet and a fixing bracket coupled to a top of the sub cabinet such that the fixing bracket is detachably fastened to the leg bracket. The leg bracket may include a bracket body coupled to the cabinet and a leg insertion hole formed through the bracket body for allowing the corresponding leg body to be inserted therethrough. The leg bracket may further include a support part formed along a circumference of the leg insertion hole, such that the support part protrudes downward toward the fixing bracket, for supporting the corresponding leg. The fixing bracket may include a location part in which the corresponding leg head is located. The location part may be formed in a shape corresponding to that of the corresponding leg head. The leg bracket may further include a fastening part extending from the bracket body such that the fastening part is detachably connected to the fixing bracket. The fixing bracket may further include a connection part formed in a shape corresponding to that of the fastening part such that the fastening part is coupled to the connection part. The fastening part may extend downward from one side of the bracket body toward the connection part. The connection part may have a shape corresponding to that of the fastening part. The leg bracket may further include a plurality of fastening holes formed such that the leg bracket is coupled to the cabinet. The fixing bracket may include a plurality of coupling holes formed such that the fixing bracket is coupled to the sub cabinet. The leg bracket may further include a leg insertion hole is provided at a position corresponding to the leg body of the corresponding leg disposed at a corresponding bottom corner of the cabinet. The leg bracket may further include a location groove in which a cabinet bracket coupled to the bottom of the cabinet for supporting the leg body is located. The location part may be formed at a position corresponding to that of the leg head in a state in which the leg bracket is coupled to the cabinet. In another aspect of the present invention, a laundry machine includes a cabinet defining a first receiving space to receive laundry to be treated, a plurality of legs each of which comprises a leg head located at an installation surface and a leg body configured to connect the leg head to the cabinet, a sub cabinet defining a second receiving space having a volume less than the first receiving space, the sub cabinet being coupled to a bottom of the cabinet, and a plurality of coupling members configured to interconnect the cabinet and the sub cabinet to support the legs, each of the coupling members including a leg bracket coupled to the cabinet and a fixing bracket coupled to the sub cabinet such that the fixing bracket is detachably fastened to the leg bracket. It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings: FIG. 1 is an exploded perspective view illustrating a conventional laundry machine including a cabinet and a sub cabinet; FIG. 2 is a perspective view illustrating a laundry machine including a cabinet and a sub cabinet according to an embodiment of the present invention, the cabinet and the sub cabinet being coupled to each other; FIG. 3 is a perspective view illustrating a laundry machine including a cabinet and a sub cabinet according to another embodiment of the present invention, the cabinet and the sub cabinet being coupled to each other; FIG. 4 is a perspective view illustrating a coupling member of FIG. 3 ; and FIG. 5 is a perspective view illustrating a leg bracket of FIG. 4 . DETAILED DESCRIPTION OF THE INVENTION Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. FIG. 2 is a perspective view illustrating a laundry machine including a cabinet 10 and a sub cabinet 20 according to an embodiment of the present invention, the cabinet and the sub cabinet being coupled to each other by connection devices. In this embodiment, as shown in FIG. 2 , the cabinet 10 and the sub cabinet 20 are coupled to each other by coupling members 30 . Specifically, each coupling member 30 is provided at corresponding sides of the cabinet 10 and the sub cabinet 20 . Each coupling member 30 is connected to the cabinet 20 by an adhesive and to the sub cabinet 20 by screws 32 . Another type of coupling members, which will be described hereinafter, may be applied to achieve easier coupling and separation between the coupling members 30 . FIG. 3 is a perspective view illustrating a laundry machine 100 according to another embodiment of the present invention, a cabinet 110 and a sub cabinet 120 being coupled to each other. Referring to FIG. 3 , the laundry machine 100 includes a cabinet 110 configured to receive laundry to be treated, a sub cabinet 120 coupled to the bottom of the cabinet 110 , and coupling members 130 configured to be detachably connected between the cabinet 110 and the sub cabinet 120 to couple the cabinet 110 and the sub cabinet 120 to each other. The coupling members 130 couple the cabinet 110 and the sub cabinet 120 to each other. The coupling members 130 are detachably connected between the cabinet 110 and the sub cabinet 120 . Since the coupling members 130 are detachably connected between the cabinet 110 and the sub cabinet 120 , it is possible to repeatedly achieve the coupling and separation between the cabinet 110 and the sub cabinet 120 . FIG. 4 is a perspective view illustrating a coupling member 130 disassembled from the laundry machine shown in FIG. 3 . Referring to FIG. 4 , the coupling member 130 includes a fixing bracket 140 disposed at the top of the sub cabinet 120 (see FIG. 3 ) and a leg bracket 160 disposed at the bottom of the cabinet 110 (see FIG. 3 ). A leg 112 of the cabinet 110 includes a leg head 112 a located at an installation surface and a leg body 112 b connected to the leg head 112 a. Since the leg 112 is generally located adjacent to a corresponding corner at the lower part of the cabinet 110 , it is preferable for the leg bracket 160 to be located adjacent to a corresponding corner at the bottom of the cabinet 110 . The leg bracket 160 is connected to the fixing bracket 140 disposed at the top of the sub cabinet 120 , with the result that the cabinet 110 and the sub cabinet 120 are detachably connected to each other. When the separation between the cabinet 110 and the sub cabinet 12 is required, therefore, it is possible to easily separate the cabinet 110 and the sub cabinet 12 from each other only by the separation between the leg bracket 160 and the fixing bracket 140 . FIG. 5 is a perspective view illustrating only the leg bracket 160 of FIG. 4 when viewed from the bottom of the leg bracket 160 . Referring to FIGS. 4 and 5 , the leg bracket 160 is disposed at the bottom of the cabinet 110 to support the leg 112 of the cabinet 110 . The leg bracket 160 is detachably connected to the fixing bracket 140 disposed at the top of the sub cabinet 120 . The leg bracket 160 includes a bracket body 162 configured to be fastened to a cabinet bracket 114 coupled to the bottom of the cabinet 110 , a leg insertion hole 162 a through which the leg body 112 is inserted, a support part 163 protruding along the circumference of the leg insertion hole 162 a , a plurality of fastening holes 164 through which screws are inserted to fasten the leg bracket 160 to the cabinet 110 , and a location groove 168 in which the cabinet bracket 114 is located. Also, the leg bracket 160 further includes a fastening part 166 configured to detachably connect the leg bracket 160 to the fixing bracket 140 . The bracket body 162 forms a body of the leg bracket 160 . The bracket body 162 is disposed at the bottom of the cabinet 110 to support the leg 112 of the cabinet 110 . (Exactly, the leg is supported by the support part formed at the bracket body.) The bracket body 162 is located adjacent to a corresponding corner at the bottom of the cabinet 110 . Therefore, it is preferable for the bracket body 162 to be formed approximately in the shape of L. The leg insertion hole 162 a , through which the leg body 112 b is inserted, is formed through the bracket body 162 at one side thereof. It is preferable for the leg insertion hole 162 a to be formed at a position corresponding to that of the leg body 112 b in a shape corresponding to that of the leg body 112 b. One or more fastening holes 164 are formed at the bracket body 162 . Screws are coupled the lower part of the cabinet 110 through the fastening holes 164 to connect the leg bracket 160 to the cabinet 110 . The fastening part 166 , configured to be connected to the fixing bracket 140 , is formed at one side of the bracket body 162 . The fastening part extends vertically downward from one side of the bracket body 162 toward the fixing bracket 140 . That is, the fastening part 166 is bent downward from one side of the bracket body 162 . It is preferable for the fastening part 166 to be formed integrally with the bracket body 162 , although the fastening part 166 may be formed of an additional member. One or more fastening parts 166 may be formed. When the bracket body 162 is coupled to the cabinet 110 , as shown in FIG. 4 , it is preferable for a pair of fastening parts 166 to be formed along regions, of the bracket body 162 , exposed to the outside. In a structure in which the fastening parts 166 are formed at the exposed regions of the bracket body 162 , as described above, it is possible for a worker to easily fasten the fastening parts 166 to connection parts 146 , which will be described later, of the fixing bracket 140 from the outside. Meanwhile, referring back to FIG. 4 , the fixing bracket 140 is disposed at the top of the sub cabinet 120 (see FIG. 3 ). The fixing bracket 140 may be formed integrally with the sub cabinet 120 . Alternatively, the fixing bracket 140 may be formed of an additional member. Since the fixing bracket 140 is connected to the leg bracket 160 described above, it is preferable for the fixing bracket 140 to be located adjacent to a corresponding corner at the top of the sub cabinet 120 . Also, in a case in which the fixing bracket 140 is formed of an additional member, the fixing bracket 140 may be fixed to the top of the sub cabinet 120 by screws. For this, the fixing bracket 140 further comprises a plurality of coupling holes 144 formed such that the fixing bracket 140 is coupled to the sub cabinet 120 . The fixing bracket 140 includes a location part 142 in which the leg head 112 a is located and connection parts 146 configured to be connected to the fastening parts 166 of the leg bracket 160 . The location part 142 defines a space in which the leg head 112 a of the cabinet 110 is located. Specifically, as shown in FIG. 4 , the location part 142 is provided with a depression 143 having a shape and size corresponding to those of the leg head 112 a. Consequently, when the cabinet 110 and the sub cabinet 120 are coupled to each other, the leg head 112 a of the cabinet 110 is located in the depression 143 defined in the location part 142 . Also, the depression 143 is formed with a shape and size corresponding to those of the leg 112 , and therefore, the movement of the leg 112 of the cabinet 110 is prevented when the cabinet 110 and the sub cabinet 120 are coupled to each other. Meanwhile, the connection parts 146 receive the corresponding fastening parts 166 of the leg bracket 160 and are coupled to the corresponding fastening parts 166 , with the result that the leg bracket 160 is coupled to the sub cabinet 120 . Consequently, each connection part 146 has a shape corresponding to that of each fastening part 166 . For example, each connection part 146 may be a depression having a shape corresponding to that of each fastening part 166 . Consequently, when the fastening parts 166 are connected to the corresponding connection parts 146 , the fastening parts 166 are inserted into the corresponding connection parts 146 to prevent the movement of the leg bracket 160 . The connection between the fastening parts 166 and the corresponding connection parts 146 may be achieved by various methods. In this embodiment, the connection between the fastening parts 166 and the corresponding connection parts 146 is achieved by screws, to which, however, the present invention is not limited. Since the connection parts 146 and the corresponding fastening parts 166 are detachably connected to each other, it is possible to easily achieve the coupling and separation between the cabinet 110 and the sub cabinet 120 . In the laundry machine according to this embodiment as described above, the coupling between the cabinet 110 and the sub cabinet 120 is achieved using the leg bracket 160 configured to support the leg 112 of the cabinet 110 without using an additional member. Consequently, it is possible to easily achieve the coupling between the cabinet 110 and the sub cabinet 120 , and, in addition, it is possible to repeatedly achieve the coupling and separation between the cabinet 110 and the sub cabinet 120 . It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

A laundry machine is disclosed. The laundry machine includes a cabinet defining a first receiving space to receive laundry to be treated, a plurality of legs each of which comprises a leg head located at an installation surface and a leg body configured to connect the leg head to the cabinet, a sub cabinet defining a second receiving space having a volume less than the first receiving space, the sub cabinet being coupled to a bottom of the cabinet, and a plurality of coupling members configured to detachably couple the sub cabinet to the cabinet. According to this laundry machine, it is possible to easily achieve the coupling and separation between the cabinet and the sub cabinet.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to dispensers and more particularly to powdered detergent dispensers for washing machines. 2. Description of the Prior Art Automated washing machines used in commercial applications have typically used powdered detergents and consume large amounts of such detergents in the course of their daily operations. It is advantageous from both time and cost standpoints for the operators of such machines to only periodically supply the machine with powdered detergent, say for example, only once during a working day. Accordingly, commercial washing machines have typically been designed for use with auxiliary detergent dispensers capable of holding sizable amounts of powdered detergent and operable to periodically convert the detergent to concentrated detergent solution as needed for use by the washing machine Such washing machines are generally configured to embody at least one wash tank or reservoir for maintaining a supply of detergent solution for use by the washing machine. The washing machine repeatedly uses the detergent solution within the reservoir for a period of time, such as one day, until it is replaced by a new solution. During normal usage, a certain amount of the detergent solution is drained off, for example with food particles and grease in dishwashing applications, to keep the remaining solution as clean as possible. Water is then added to the reservoir to maintain the proper level. This reduces the concentration of the solution in the reservoir. In order to keep the detergent solution in the reservoir at the proper concentration, concentrated detergent solution is periodically added to the reservoir by the auxiliary detergent dispenser. Use of an automated detergent dispenser system eliminates the need of constant operator attention to the status of the reservoir solution and provides greater accuracy in maintaining the actual concentration level of the detergent solution within the reservoir. Many automatic auxiliary detergent dispensing systems have appeared in the prior art. Such dispensers can be generally charactertized by: (1) those dispensing systems which are remotely located (usually in a different physical location) from the washing machine proper, and (2) those dispensing systems which are configured for mounting to or directly adjacent the washing machine proper. The remotely located dispensers are typically configured for handling large 30 to 50 gallon shipping containers of powdered detergent and for directly converting the detergent within these containers into a concentrated detergent solution. Dispensers of this type have selfcontained reservoirs for maintaining a supply of the concentrated solution produced, and a pump for transferring on demand the concentrated solution from the dispenser reservoir to the wash tank of the washing machine proper. In general, such apparatus requires considerable space oftentimes not available on the premises where the washing machine is located, are somewhat cumbersome to use since large shipping containers must be handled by the operator, and do not generally lend themselves to efficient use with smaller or occasionally used washing machines. Dispensers within the second-listed catagory, and to which this invention pertains are much smaller than their remotely located counterparts, and are sized to hold relatively smaller amounts of detergent, thus enabling ease of loading by a wide range of machine operators. Such dispensers can be readily mounted in out-of-the-way positions directly to the washing machine proper, typically on top of the washing machine, and are generally more versatile in their application then the remotely located dispensers. These dispensers are generally loaded from the top and directly supply the adjacent washing machine reservoir with their produced detergent solution by gravity feed, thus eliminating the need and expense for pump means and providing an added dimension of reliability. Most prior art dispensers of the type which are connected directly to the washing machine have been configured for mounting on top of the machine or within the chassis of the machine generally overlying the wash tank or reservoir. In such dispensers, it has been commonplace to totally immerse the detergent powder in water to form a saturated solution or slurry. A stand pipe usually located in the middle of the dispenser holding tank or pot, maintains a constant water level within the dispenser. When the washing machine requires additional detergent solution for the wash tank, a controller opens a solenoid valve which causes water to flow into the dispenser pot. The added water causes a portion of the saturated solution in the pot to flow into the stand pipe and to fall directly into the underlying wash tank. When the detergent concentration level in the wash tank attains a predetermined level of concentration, the controller shuts off the water supply to the dispenser by closing the solenoid valve. A drawback of the above-described device is that since the detergent is always saturated, the concentration level of the detergent solution produced by the dispenser over a period of time will vary as the detergent solution within the dispenser pot is diluted. Further, such apparatus cannot be used with powdered detergents containing active chlorine, since most of the chlorine contained in such detergents is lost through decomposition once the detergent is wetted. Such top mounted dispensers are also dangerous to an operator responsible for loading powdered detergent into the dispenser pot. Due to the position of the dispenser over the washing machine, the heat from the machine raises the solution temperature within the dispenser pot to near the wash temperature (i.e. approximately 150° to 160° Fahrenheit). When caustic containing compounds are rapidly added to the dispenser pot, the heat of hydration may cause the solution to boil, presenting a hazardous situation to the operator. This hazard is increased by the fact that due to the top mounting of such dispensers, the operator is required to load such apparatus at or above eye level, thus increasing the danger of caustic splash or spray to his face and eyes. In an effort to avoid many of the above problems, some dispensers have been configured so as to support a mass of powdered detergent within a large inverted container over a screen mesh and so as to form a detergent solution by wetting the powdered detergent by means of a spray directed through the screen. Such dispenser construction has been successfully used with the large remotely located type of dispensers which employ an underlying reservoir and a pump for forwarding the prepared solution to the washing machine. While some of these principles have been applied to dispensers of the type mounted on or adjacent to the washing machine, none of the prior art dispensers of this type offer that combination of features which solve all of the above problems in a manner that is completely non-hazardous to the attending operator. One example, of such a prior art dispenser theoretically mountable to a washing machine, supports a mass of powdered detergent on a conical screen suspended within a top loading housing. The carried detergent is dissolved by means of a spray of water directed against the convexly shaped surface area of the screen. While this device solves many of the prior art problems associated with such machine mounted dispensers, its design enables excessive penetration of the spray into the detergent, causing extensive hydration thereof, making this device unattractive for use with active chlorine containing detergents. Further, this dispenser does not include any safety features for protecting an operator loading the dispenser. The present invention overcomes the above-mentioned shortcomings of the prior art powdered detergent dispensers of the type configured for mounting on or adjacent the washing machine. The dispenser apparatus of the present invention provides a simple non-hazardous and reliable technique for producing highly concentrated detergent solution for use on a demand basis by an attached or adjacent washing machine, produces such solutions which are of substantially uniform composition and concentration throughout the conversion of the entire contents within the detergent dispenser, and minimizes waste due to unusable residues remaining in the dispensing container. The configuration of the dispenser container enables the dispenser to be mounted on the side wall of the washing machine at a level so as to enable ease of operator loading and at a height which does not present a direct hazard to the face and eyes of the operator. Further, automatic safety features of the invention disable operation of the dispenser spray apparatus whenever the loading port is opened by an operator. SUMMARY OF THE INVENTION The present invention includes a housing member particularly suitable for attachment to the side wall of a washing machine or to a vertical wall adjacent the washing machine. The housing member includes an upper cylindrical-storage portion for retainably holding a mass of powdered detergent, and defines an upwardly disposed mouth or access port through which powdered detergent is loaded into the housing. The access port is normally covered by means of a door member pivotally mounted to the housing. The lower portion of the housing member is configured in a funnel shaped collector portion downwardly converging to an outlet port. The housing member is designed for mounting such that the vertical height of the outlet port from the collector portion of the housing is higher than that of the wash tank or reservoir of the washing machine. A conduit is connected to the outlet port of the housing member for directing detergent solution therethrough by means of gravity feed from the collector portion of the dispenser to the reservoir of the washing machine. A symmetrically curved continuous screen member is mounted to the inner walls of the housing member at a position therealong defining the intersection of the upper storage portion and the lower collector portion of the housing member. The screen member is curved so as to appear concave with respect to the underlying collector portion and has a screen mesh sized to retainably carry powdered detergent thereabove within the upper storage portion. The screen member forms a snug fit with the inner walls of the housing member so as to prevent the passage of liquid therebetween. Spray forming nozzle means are axially mounted in the collector portion of the housing member and is disposed below the screen member in a position tangential and equidistant to all points of the screen member so as to direct a uniform spray at substantially the entire downwardly facing surface of the screen member. The relative positioning between the nozzle means and the screen member is such that the spray emanating from the nozzle means impinges generally perpendicularly upon the screen member across its entire downwardly facing surface. The nozzle means are connected to a pressurized source of water by means of a water supply line. Spray control means including a valve in the water supply line controls the flow of water to the spray-forming nozzle. In operation, the valve normally blocks water flow to the nozzle and is operative in its open position only upon receipt of an external control signal. Upon receipt of such a control signal, water flow is directed through the supply line and the nozzle means and into engagement with substantially the entire lower surface of the screen member. Spray from the nozzle means is of relatively low pressure and wets only that portion of the powdered detergent carried immediately above the screen member. The wetted detergent passes in solution through the screen member and is directed by the underlying collector portion of the housing member to the outlet port thereof and through the conduit to the reservoir of the washing machine. The control signal may be applied to the spray control means either manually, or automatically by means of an electronic control module. The electronic control module generally includes a conductivity cell disposed within the reservoir for sensing the conductivity/dilution of the detergent solution therein. When the conductivity of the detergent solution within the reservoir falls below a predetermined level, the electronic control module provides an energizing control signal to the spray control means for opening the valve in the water supply line. When a sufficient amount of concentrated detergent has been added to the reservoir, the conductivity cell indicates a satisfied condition and directs the electronic control module to remove the control signal from the spray control means, thus closing the water supply line. A safety control switching circuit is connected to sense the operative position of the door member covering the access port to the housing member and prevents water spray from the nozzle whenever the door member is not secured in its closed position overlying the access port. Therefore, an operator cannot be injured by the spray of highly caustic matter while loading the dispenser apparatus. While the present invention will be described in combination with a particular configuration of the dispenser housing member, it will be understood that other configurations could be designed within the spirit and intent of this invention. Further, while the preferred embodiment of the invention will be described in combination with specific electronic control modules for providing control signals to the spray control means regulating water flow to a spray nozzle, it will be understood that other control circuits could equally well be configured within the spirit and intent of this invention. Similarly, while specific safety feature circuits and techniques will be described with respect to the preferred embodiments of this invention, other safety control means including purely mechanical linkage safety systems could equally well be devised within the scope of this invention which would render the dispensing apparatus non-hazardous to an operator of the device. BRIEF DESCRIPTION OF THE DRAWING Referring to the Drawing, wherein like numerals represent like parts throughout the severals views: FIG. 1 is a view in front elevation with portions thereof broken away, of a powdered detergent dispenser constructed according to the principles of this invention; FIG. 1a is a partial sectional view of the powdered detergent dispenser of FIG. 1, illustrating an embodiment thereof which employs a conically shaped screen member. FIG. 2 is a view in side elevation of the powdered detergent dispenser disclosed in FIG. 1; FIG. 3 is an enlarged fragmentary view with portions thereof broken away of the lower part of the collector portion of the dispenser apparatus disclosed in FIG. 1; FIG. 4 is an enlarged sectional view of the safety control switch portion of the preferred embodiment of the dispenser apparatus disclosed in FIG. 1; FIG. 5 is a schematic block diagram illustrating the circulartory and basic electrical signal flow paths of the dispensing system of one embodiment of this invention; and FIG. 6 is a schematic block diagram illustrating the circulatory and basic electrical signal flow paths of the dispensing system of a second embodiment of this invention. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the Figures, there is generally disclosed at 20 a container or housing member. The housing member has a generally cylindrical upper storage portion 22 having a cylindrical inner wall 23. The wall 23 defines an internal cavity 24. The upper terminous of the storage portion 22 defines a mouth or access port 25 into the cavity 24 of the storage portion 22. The inner wall 23 of the housing member 20 converges in the downward direction, defining a lower funnel-shaped collector portion 26 of the housing member 20. The inner wall 23 of the housing member 20 is configured to form an annular flange at 27 circumferentially extending around the inner wall 23 of the housing member 20 at the juncture of the upper storage portion 22 and the lower collector portion 26. The lower terminous of the collector portion 26 defines an outlet port 28 from the internal cavity 24 for passage therethrough of solution collected by the collector portion 26. The outlet port 28 has a hose clamp extension 29 having a plurality of annular ribs configured for engaging the inner walls of a connecting hose or conduit 30. The container or housing member 20 may be constructed of any suitable material which is capable of withstanding exposure to highly caustic detergent solutions, and is preferably configured of stainless steel or molded plastic material. A pair of mounting plates 32 are connected to and extend rearwardly from the outer surface of the housing member 20 for securely mounting the housing member 20 to a vertical side wall, generally designated at 100 of a washing machine, schematically illustrated at 105 in FIGS. 5 and 6. A brace member 33 extends across the back surface of the housing member 20, connecting the pair of mounting plates 32 and adding structural support to the dispenser housing member 20. A door member 34 is sized to extend entirely across and to sealingly close the mouth or access port 25 to the internal cavity 24 of the housing member 20. The door member 34 is pivotally mounted to the brace member 33 at 35 for pivotal motion between a closed position, illustrated in full line in FIGS. 1 and 2, to an open position, illustrated in dashed lines in FIG. 2. The lower collector portion 26 of the housing member 20 has an outwardly projecting coupling portion 38 extending from the collector portion 26 adjacent the outlet port 28 of the collector portion 26. A tube fitting insert member 39 is secured within the coupling projection 38 and projects through the inner wall 23 of the collector portion 26 of the housing member 20. A spray-forming nozzle 42 is threaded into the end of the tube insert 39 and is axially aligned within the inner cavity 24 of the housing member 20 in a direction so as to direct an upwardly projected spray pattern therefrom. The tube fitting insert member 39 is provided with an O-ring seal 40. A screen member 50 symmetrically curved in a hemispherical or conical shape about (see FIG. 1a) the longitudinal axis of the internal cavity 24 is mounted in resting engagement upon the annular flanged portion 27 of the housing member 20. The curved screen member 50 includes a screen mesh 50a supportingly mounted over a wire frame support structure 50b. The mesh size of the screen 50a is sized so as to prevent powdered detergent from passing therethrough. The outer periphery of the screen member 50 extends beyond the inner edge of the flange portion 27 of the housing member 20 (when viewed from below). A retaining circular wire member 52 engages the upper portion of the screen member 50 about its periphery and is sized to frictionaly engage the inner walls 23 of the housing member 20 so as to retainably hold the screen member 50 into firm engagement with the flange portion 27. An upper extension 50c of the wire frame member 50b projects upwardly into the upper storage portion 22 of the container 20 and acts as a handle for enabling removal of the screen member 50 from the housing member 20 for maintenance and repair purposes. The screen member 50 is curved in the direction so as to appear concave when viewed from the collector portion 26 of the housing member 20. The curvature of the screen member 50 with respect to the spray-forming nozzle 42 is such that the screen mesh 50a is tangential and substantially equidistant at all portions therealong from the center of the spray-forming nozzle 42. Similarly, the spray pattern emanating from the nozzle 42 is upwardly directed against the screen mesh 50a of the screen member 50 so as to substantially wet the entire surface area of the screen mesh 50a, and such that the spray impinges upon the screen mesh in a direction generally perpendicular thereto at all points therealong. A water supply inlet pipe 55 is connected to the tube insert 39 and is in communication therewith for providing a source of water flow to the spray-forming nozzle 42. The water supply line 55 passes through one of the mounting plate members 32, as illustrated in FIGS. 1 and 2, and receives structural support therefrom. A siphon breaker 56 interrupts the water supply line 55. A safety switch 60 is mounted to the door member 34 for movement therewith and senses the operative position of the door member 34 relative to the mouth or access port 25 of the housing member 20. In the preferred embodiment, the safety switch 60 comprises a mercury actuated switch, diagrammatically illustrated in FIG. 4. Referring thereto, the switch 60 generally has a pair of contacts 61a and 61b projecting within an insulating bulb member 62 which entraps a fluid conductive medium 63 such as mercury. The switch 60 is mounted upon the door member 34 such that when the door member 34 is operatively positioned so as to close external access to the upper storage portion 22 of the housing member 20, the mercury 63 provides an electrical shorting path between the first and second terminals 61a and 61b of the switch 60, as illustrated in FIG. 4. When the door member 34 is pivotally open so as to enable access to the internal cavity 24 of the housing member 20, the mercury 63 flows within the bulb member 62 away from engagement with the first terminal 61a so as to break the electrical circuit path between the terminals 61a and 61b, thus electrically opening the switch 60. Conduction paths are provided from the first and second terminals 61a and 61b respectively of the switch 60 by means of a pair of conductor members 64a and 64b respectively. A block diagram of the circuit and fluid flow paths for the dispenser apparatus as connected within a hydraulic, manually controlled system is illustrated in FIG. 5. Referring thereto, the dispenser housing member 20 is illustrated as mounted to the side wall 100 of a washing machine, generally denoted at 105. The washing machine 105 has a wash tank or reservoir 106 for storing a supply of detergent solution for use within the machine. The hose or conduit 30 extends from the outlet port 28 of the housing member 20 and is connected to a hose clamp extension 107 (see FIG. 2) extending through the side wall 100 of the washing machine 105 and terminating at a position directly overlying the reservoir 106. The washing machine 105 also has a main fresh water supply line 55a connected to a pressurized source of water (not illustrated). The main water line 55a directly provides clean rinse water to the rinse section 111 of the machine and branches out to the water supply line 55 for providing fresh water to the spray-forming nozzle 42. A rinse valve 108, either manually or electronically controlled, is connected in the main water supply line 55a at a position upstream from the rinse head and upstream from the the input to the water supply line 55. A flow control valve 109 is connected in the water supply line 55 leading to the spray-forming nozzle 42 and regulates the rate of flow of water to the spray-forming nozzle 42. A safety control valve 110 is connected in the water supply line 55 either upstream or downstream from the flow control valve 109. The safety control valve 110 is, in the preferred embodiment, a solenoid actuated valve having an input control terminal 110a and a common terminal generally designated at 110b. The common terminal 110b is directly connected to a reference potential generally designated at 200. The first conductor 64a leading from the safety switch 60 is directly connected to an appropriate power source 201. The second conductor 64b leading from the safety switch 60 is directly connected to the control input terminal 110a of the solenoid actuated safety control valve 110. A block diagram of the circuit and fluid flow paths for the dispenser apparatus as connected within an electronically controlled dispensing system is illustrated in FIG. 6. Referring thereto, the detergent dispenser housing member 20 is illustrated as mounted to the side wall 100 of the washing machine 105 at a position above the wash tank or reservoir 106 of the machine such that the conduit 30 and associated hose connecting extension 107 dispense the contents of the collector portion 26 of the housing member 20 directly into the reservoir 106. The water supply line 55 is directly connected to a source of pressurized water (not illustrated). A solenoid controlled valve 112 is connected in the water supply line 55 between the spray-forming nozzle 42 and the water supply source. The solenoid valve 112 has an input control terminal 112a and a common terminal 112b which is directly connected to a ground potential 200. The first conductor 64a leading from the safety switch 60 is directly connected to the power source 201. While not disclosed, it will be understood that the power source 201 may represent any appropriate source of electrical power suitable for energizing the electronic components described herein. Similarly, while not illustrated, it will be understood that the water supply source may be any fluid supply source capable of continuously directing a flow of water under pressure through the water supply lines 55 and 55a. The second conductor 64b leading from the safety switch 60 is connected to a positive power supply input terminal 120a of an electronic control module 120. The electronic control module 120 further has a reference supply input terminal 120b which is directly connected to the common potential 200, a first signal input terminal 120c, a second signal input terminal 120d and a signal output terminal 120e. The signal output terminal of the electronic control module 120 is directly connected to the control input terminal 112a of the solenoid valve 112. The first and second signal input terminals 120c and 120d respectively of the electronic control module 120 are directly connected by means of a pair of signal flow paths 122 and 123 respectively to the terminals of a conductivity cell 125. The conductivity cell 125 is mounted within the reservoir 106 of the washing machine 105 for sensing the electrical conductivity of the solution contained therein. In the preferred embodiment, the electronic control module 120 may be functionally identical to that of the electronic control network described in U.S. Pat. No. 3,680,070 to Marcus I. Nystuen, owned by the common assignee of this invention. In general, the electronic control module 120 is normally operable to provide a de-energizing signal output at its output terminal 120e when the conductivity cell 125 indicates that the conductivity (i.e. the detergent concentration level) of the detergent solution within the wash tank or reservoir 106 is at or above a predetermined level and is operable to produce an energizing output signal at its signal output terminal 120e whenever the conductivity cell 125 indicates that the conductivity (concentration level) of the solution within the reservoir 106 has dropped below a predetermined minimum level. The signal output appearing at the output terminal 120e of the electronic control module is used to energize the input control terminal 112a of the solenoid valve 112. The circuits within the electronic control module 120 are energized from the power source 201 by means of the serially connected safety switch 60. Therefore, whenever the safety switch is operative in a non-conducting (open) mode, the electronic control module circuits will be disabled, preventing passage of an energizing signal to the solenoid valve 112, regardless of the conductivity indication status of the conductivity cell 125. The conductivity cell 125 may be of any type of such cell well known in the art, which provides an electrical output signal that varies in response to the electrical conductivity of the solution in which it is immersed. It will be understood that other configurations for the electronic control module 120 could be designed within the spirit and scope of this invention. For example, the electronic control module 120 could also comprise those circuits detailed in the electronic control network described in U.S. Pat. No. 3,879,675 to Marcus I. Nystuen et al, owned by the common assignee of this invention. The electronic control apparatus of this alternate embodiment energizes the conductivity cell 125 by means of short periodic pulses of DC current to avoid polarization of the cell, and is particularly useful for higher concentrations of electrolyte solutions. OPERATION OF THE PREFERRED EMBODIMENT Operation of the dispensing apparatus of this invention is relatively simple and is briefly described below. A mass of powdered detergent is loaded into the upper storage portion 22 of the housing member 20 through the upper mouth or access port 25. To load the dispenser apparatus the door member 34 must be lifted to an upright position as indicated in dashed lines in FIG. 2. The powdered detergent is retainably carried by the curved screen member 50 above the spray-forming nozzle 42. In the preferred embodiment, the housing member 20 will typically hold 8 pounds of powdered detergent but can be readily sized to hold up to 15 pounds of powdered detergent; however, it will be understood that other sizes could equally well be configured within the scope of this invention. When the member 34 is raised out of sealing engagement overlying the access port 25, the mercury 63 within the safety switch 60 will be disposed within the bulb portion 62 of the safety switch 60 (see FIG. 4) so as to electrically open the signal path between the first and second terminals 61a and 61b respectively of the safety switch 60. With respect to the hydraulic application of the invention (FIG. 5) the solenoid valve 110 is connected so as to be positioned in an open position, enabling fluid flow through the water supply line 55 when in receipt of an energizing signal from the safety switch 60. However, when signal flow to the solenoid valve 110 is blocked by means of the safety switch 60, the solenoid valve 110 will close, blocking further fluid flow to the spray-forming nozzle 42. In the apparatus disclosed in FIG. 5, under normal operation, a fluid flow path is established from the water source through the water supply line 55 to the spray-forming nozzle 42 whenever the rinse valve 108 is opened, either electronically or manually. When provided with fluid flow therethrough, the spray-forming nozzle will direct a spray pattern at the bottom surface of the screen mesh 50a of the screen member 50, wetting that detergent carried immediately thereabove, which dissolves and passes in solution through the screen mesh to the collector portion of the housing member 20. Thus, concentrated detergent solution is produced in this arrangement of the apparatus, whenever the rinse valve 108 is opened and the door member 34 is closed so as to enable the safety switch 60. The concentrated detergent solution passes through the outlet port 28 of the housing member 20 and is directed by the hose or conduit 30 into the reservoir 106 of the washing machine 105. In that configuration of the invention disclosed in FIG. 6, the electronic control module 120 is enabled by means of the safety switch 60 whenever the door member 34 is closed in its downward position over the access port 25 to the housing member 20. The solenoid valve 112 is operative to normally block flow of water through the water supply line 55 in the absence of receipt of an energizing signal at its signal input terminal 112a. The conductivity cell 125 measured the conductivity of the solution within the reservoir 106 of the washing machine 105. As the detergent solution within the reservoir 106 is diluted during washing or rinsing operations, the conductivity of the detergent solution will drop. When the conductivity of the detergent solution in the reservoir drops below a predetermined threshold level, the conductivity cell 125 communicates this information by means of the signal flow paths 122 and 123 to the electronic control module 120. If enabled by means of the safety switch 60, the electronic control module 120 will produce an energizing output signal at its signal output 120e for energizing the solenoid valve 112. Upon receipt of an energizing signal, the solenoid valve 112 will open, allowing water to flow through the water supply pipe 55 for producing a spray at the spray-forming nozzle 42. The spray thus produced will continuously dissolve that powdered detergent immediately adjacent the screen member 50, which passes in solution as above described into the reservoir 106. When a sufficient amount of concentrated detergent solution has been added to the reservoir so as to re-establish the predetermined conductivity level therein, the conductivity cell 125 communicates this information to the electronic control module 120 which removes the enabling output signal from its signal output terminal 120e, thus disabling the solenoid valve 112. If for any reason an operator should move the door member 34 from its downward position while the solenoid valve 112 is open, the safety switch 60 will disable the electronic control module, effecting a disabling of the solenoid valve 112 and immediately closing the water supply line 55. Thus an operator is always protected from hazardous spray of highly cautic detergent solutions which can be severely damaging to his face and eyes. The housing member of this invention need not be mounted on top the washing machine, and can be positioned on the side wall 100 of the washing machine 105 at a height above the solution level within the reservoir 106, which is conveniently accessible to an operator for loading operations. The side mounting feature of this invention also provides additional safety to the operator by providing increased distance between the operator's face and the inlet port to the dispenser housing member, thus minimizing the possiblity of hazardous splash to the operator face when lifting the door member 34. Further, the unique screen and spray nozzle configuration of this invention renders this dispenser apparatus particularly attractive for use with powdered detergents containing active chlorine due to the minimization of wetting of the powdered detergent and the absence of channeling therethrough. Other modifications of the invention will be apparent to those skilled in the art in light of the foregoing description. This description is intended to provide concrete examples of individual embodiments clearly disclosing the present invention. Accordingly, the invention is not limited to these embodiments or to the use of specific elements therein. All alternative modifications and variations of the present invention which fall within the spirit and broad scope of the appended claims are covered.

A non-hazardous dispenser apparatus for converting powdered detergent, including those containing active chlorine, into a concentrated detergent solution for use by a washing machine. A curved screen member retainably supports a mass of powdered detergent thereabove within a generally cylindrical container configured for mounting to the side wall of a washing machine adjacent the detergent solution carrying reservoir thereof. A single spray-forming nozzle is mounted within the container and below the curved screen for directing a uniform spray of water at substantially the entire downwardly facing concave surface of the screen member. Only that detergent carried immediately above the screen member is wetted by the spray and passes in solution through the screen, after which it is collected and directed by a collecting portion of the container, into the washing machine reservoir. Spray control means, either manual or electronic, controls the spray of water through the nozzle in response to the concentration level of detergent within the washing machine reservoir. The container is loaded through an upper access port normally closed by a door member. Safety switch means disables spray from the nozzle whenever the door member is open.

BACKGROUND OF THE INVENTION The present invention relates to the reinforcement of high-tension-resistant steel for prestressed concrete members or buildings. In the production of prestressed concrete and also with prestressed concrete buildings or members, as, for example, in prestressed concrete pressure containers, the reinforcemens are wound under tension onto the outside of the container wall and later, to prevent corrosion, are enveloped with a corrosion inhibitor or compact material, e.g., cement mortar. The adherence of the reinforcements is of considerable importance. This applies especially to reinforcements which are embedded without end anchoring in the cement mortar. It is also applicable to reinforcements which are located through intermediate anchoring, e.g., on a container wall or at the rear wall by winding channels placed in a container wall. These horizontal windings channels of rectangular cross section are at first open toward the outside, but later are pressed out, e.g., after a one-time or repeated retensioning (restressing) of the reinforcements with the corrosion inhibitor or compact material. Such reinforcements, depending on the internal pressure prevailing in the pressure container or depending on the circumferential stress occurring in the container wall, the counteracting circumferential stresses to be generated by the reinforcements in the container wall, are wound in several layers running radically on top of one another and in helical windings adjacent to one another. The tight enveloping of each reinforcement winding and layer by the corrosion inhibitor or compact material is of great significance. This applies especially when using a compact material e.g., cement mortar, or a tightly closed compact cross section is to be formed. It is also important in view of possible reinforcement breakage and its consequences. The more perfectly the reinforcement windings and layers are embedded in the cement mortar, the smaller is the likelihood that during a reinforcement break an entire reinforcement layer, if only between two intermediate anchorings, unravels. For such perfect embedding of the reinforcements it is necessary that the reinforcements, both within each layer between their windings, and also from layer to layer are sufficiently spaced apart so that the cement mortar to be introduced later, can seep through to all interstices. However, such spacings within a reinforcement bundle or within a reinforcement layer must also be present if the reinforcements and/or their windings are to be enveloped by a protective material, e.g., rust-proofing grease, instead of by a compact material. Otherwise, during the subsequent introduction of such material, there is no guaranty of a perfect rust-proof envelopment of the reinforcements by the material. It is already known in the art how to increase the adherence of the reinforcements by their profiling. It is also already known to have reinforcements of round or oval cross section made from rod-or ribbon-like reinforcement steel in the manner of twisted concrete cross section steel. Known, furthermore, is the so-called rack tool steel which is provided with a large number of small small beads to increase the adherencce effect. It is, moreover, known to use instead of homogeneous round or oval steels for the formation of multilayer outside windings on container walls or in winding channels of the kind stated above, stranded cables of high-tension-resistant steel wires which can be produced with a relatively large cross section and can be bent with a small radius of curvature. For example, seven-strand cables with an outside diameter of 10 to 15 mm and cross sections of about 140mm 2 or larger, are particularly well-suited for reinforcement windings of the type described. They have good relaxation and stress-removal properties for manufacture. Also, such stranded cables, in contrast with homogenous round or oval steel of similar cross-section sizes, can be manufactured in very long lengths, so that much fewer reinforcement joints than with homogeneous steel are required. However, in the case of reinforcements with a large number of stranded cables or stranded cable windings, the grooves between the tightly packed strands or their windings do not provide sufficient space to make possible complete penetration of a reinforcement bundle or packet and a perfect enveloping of the individual reinforcements and/or their windings. Even with the known ribbed or beaded rack tool steel and stranded cables, where the outside wires are profilated, i.e. provided with ribs, this possibility does not exist. These ribs are to provide better adherence to the concrete and a more simple anchoring. Since for stranded cables, without exception, colddrawn wires of high strength are used, only very low ribs can be produced if the strength of the steel is not diminished. The rib heights are around 0.15 mm. Therefore, it has been proposed that spacers be inserted into a winding or tensioning channel. These spacers separate both individual stranded cables or reinforcements of rod- or ribbon-like reinforcement steel, and individual windings and/or layers of such reinforcements. During the subsequent pressing out of the winding or reinforcement channel, these spacers make possible the free flow of the protective material e.g., of cement mortar. However, the installation of such spacers requires extra effort and restricts the use of machines for bundling the reinforcements. It is, therefore, an object of the invention to provide a reinforcement comprising either a homogeneous reinforcement steel or a multistranded cable in such a way that both its adherence to a protective or compact material is improved, and assurance is provided that during winding around a concrete member or building, e.g., a container wall, there is formed inside or outside the winding channel a mutual space between the reinforcement windings and the reinforcement layers; this space must be large enough to assure complete envelopment of the reinforcement by the protective or compact material. Another object of the present invention is to provide a reinforcement of the foregoing character which is simple in design and may be economically fabricated. A further object of the present invention is to provide a reinforcement arrangement as described, which has a long service life. SUMMARY OF THE INVENTION The objects of the present invention are achieved by providing that the reinforcement comprises rigidly attached risers protruding greatly from its circumference. Passthrough locations and paths between these risers and the reinforcement periphery permit complete embedding of the reinforcement bundle or packet, consisting of one or several reinforcements, in a subsequently introduced corrosion inhibitor or compact material, e.g., cement mortar. The spacing risers may be shaped and arranged in various ways. With a first embodiment of the present invention, which can be used both with rod- or ribbon-like reinforcement steels and with stranded-cable reinforcements, the risers may be annular risers spaced apart in the lengthwise direction of the reinforcement. Such annular risers may be made of steel or synthetic material and may be crimped on and/or bonded to the stranded cable in the factory. Preferably, the annular risers are sleeve-shaped and provided along their outer periphery with annular profilations which may be formed by helical wave indentions. In accordance with the present invention, the spacing risers in the case of a reinforcement made of rod- or ribbon-like reinforcement steel may be rolled on in the form of longitudinal ribs in the factory. However, when the reinforcement comprises a multistranded cable, the spacing risers may also be formed by an outermost cable strand which has a larger diameter than the other cable strands, and which constitutes a spacer wire. The outer part of the latter's cross section noticeably protrudes beyond the periphery of the cable. With this embodiment, the reinforcement, comprises a separate stranded cable where the spacer wires constitute a force-absorbing part of the cable itself. The spacing risers may also be formed, instead of by cable strands, by at least one extra spacer wire which runs in a groove between two outer cable strands helically around the cable in accordance with the stranding. Finally, the spacing risers may be formed by winding round or profilated wire around the reinforcement. The windings of this wire are spaced apart. In comparison with conventional reinforcement stranded cables, a reinforcement in accordance with the present invention, because of the spacing risers, has a vastly increased adherence and the additional advantage that the risers form spacers. With reinforcement windings of the type stated or when arranging reinforcements in the form of reinforcement bundles or packets, these spacers make sure that adjacent reinforcements or reinforcement windings of each reinforcement layer and also successive reinforcement windings themselves are wound with a mutual spacing such that a corrosion inhibitor material or a compact material, e.g., cement mortar can be forced into the entire reinforcement packet and each reinforcement winding and each reinforcement layer can be fully enveloped by the material. This makes possible not only perfect corrosion protection of the reinforcements, but, when using a compact material, every reinforcement and especially the outer layer of a multilayer reinforcement winding or of a reinforcement bundle or packet is solidly embedded. Hazardous consequences of a possible reinforcement break are reduced to a large degree. The winding of the reinforcements is not impeded in any manner; with reinforcement windings placed, e.g., around the side walls of a pressure container, the winding can be accomplished easily with a winding machine in accordance with the German Pat. No. P 21 29 978.5. If the reinforcement comprises a stranded cable provided with spacing risers, since as a rule stranded cables can be manufactured in very long lengths and the risers of the present invention can be attached to very long stranded cables, the winding is even made easier because much fewer reinforcement joints are required than with rodlike reinforcements. Bulgingout of the winding by possibly wound joints do not impair the functioning of the winding. With reinforcement windings which, as already mentioned, e.g., with pressure container with horizontal winding channels running along its periphery and open toward the outside are located in winding channels of rectangular cross section, by later forced embedding of the winding channel in a compact material, e.g., cement mortar, a perfect subsequent adherence can be brought about. As experiments have shown, this adherence fully complies with the directives (regulations) governing subsequent adherence. Preferably, the winding channels are made with disposable casing of corrugated sheet iron; the wave depth should correspond to the proven steel jacket encasing tubes with corrugated walls. Corrugation of the boundary surfaces of the winding channels facilitates lateral flow-around the reinforcement winding when later embedding the winding channels in the compact material. The reinforcements provided with spacing risers can, with any embodiment of the risers, be anchored in the winding channels by means of conventional end anchoring. If necessary, they can be wound around the vertical guide strips located in the winding channels so that, in plan form, with a winding channel of circular vertical rear wall, the winding becomes like a polygon. To inject the winding channels with the compact material, e.g., cement mortar, the winding channels are closed at their open end with removable steel covers or by accessory concrete anchored toward the rear in the winding channels, and then the compact material is injected from the bottom toward the top and flowing laterally. This makes sure that the mortar can penetrate through the pass-through spaces formed between the spacing risers and the periphery of each reinforcement for any embodiment of the risers to all reinforcements or reinforcement layers and reinforcement windings and can fill all interstices. If the reinforcement consists of a stranded cable and the spacing risers are formed by one or more outer cable strands of larger diameter than the other cable strands, or by one or more additional wires which run in a groove between two cable strands helically around the cable, the spacer wires thus formed can be made of the same high-grade material and therefore participate in the prestressing effect. The cross section of the space wires may be either round or profiled. The spacer wires loosen a bundle of tightly packed cables by forming in them flow-through locations in the form of helical channels which combine with the grooves between the cable stands and thus create sufficient possibilities for the mortar to flow through. When using prestressed-concrete stranded cables with spacer wires in reinforcements with subsequent adherence, the smooth continuous spacer wire does not cause any higher friction losses. If alternately right- and left-handed stranded cables are used in one reinforcement, the spacer wires cross one another and touch only at the points of intersection. This enlarges the flow-through cross section for the mortar. With circumferential prestressing of prestressed concrete pressure containers, the intersections of the spacer wires can be designed in such a way, that the various winding layers are alternately wound with right- and left-handed stranded cables. The novel features are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a partial length of a reinforcement consisting of a stranded cable; Fig. 2 is a side view corresponding to FIG. 1 of a reinforcement consisting of homogeneous prestressed steel; FIG. 3 shows a cross section taken along line III--III of FIG. 1; FIG. 4 shows a cross section taken along line IV--IV of FIG. 2; FIG. 5 is the side view of a reinforcement bundle consisting of reinforcements in accordance with the present invention; FIG. 6 is the side view of a partial length of another embodiment of a reinforcement made of homogeneous prestressed steel; FIG. 7 is the top view for FIG. 6; FIG. 8 shows a partial cross section through a reinforcement bundle comprising reinforcements in accordance with FIG. 6 and 7; FIG. 9 and 10 show cross sections through other embodiments of a reinforcement comprising a stranded cable; and FIG. 11 shows a further embodiment of a reinforcement consisting of ribbonlike reinforcement steel. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawing the reinforcement shown in FIGS. 1 and 3 comprises a seven-wire stranded cable 1 which may have, for example, an outside diameter of about 10 to 15 mm and a cross sectional area of about 140 mm 2 . At intervals of 6 to 100 cm, the stranded cable has annular risers 2 (attached in the factory) which, in the embodiment shown, are in the form of sleeves. The intervals between the annular or sleeve-shaped risers 2 may be, as shown in FIG. 5, identical and equal with the individual stranded cables. However, this is not necessary. Along their outer periphery, the sleevelike risers 2 have annular profiles formed, as shown, by helical grooves. The sleevelike risers 2 may be made of steel and be pressed onto stranded cable 1 by the exertion of radial pressure forces and as a result may be rigidly connected to the stranded cable. For easy fastening to stranded cable 1, the sleevelike risers 2 may be provided with a radial groove 4 as shown in FIG. 3. The risers 2 may also be connected rigidly by bonding to each stranded cable. In any case, the annular or sleevelike risers 2 constitute spacers through which all reinforcements or reinforcement turns contained in one reinforcement winding or in one reinforcement bundle, as shown in FIG. 5, are wound or arranged maintaining mutual distances 5. These correspond to the amount of radial protrusion of risers 2 over (beyond) the periphery of the stranded cable 1. In this manner there are formed between the annular risers 2 of stranded cables 1 and the circumference of the stranded cables, numerous pass-through locations or paths which are supplemented at the outside surface of the sleevelike risers by the paths formed by the wave valleys of profile 3 of the risers. For later embedding of the reinforcements and reinforcement windings in a corrosion inhibitor or a compact material, e.g., cement mortar, this material upon pressing into a winding channel, for example, can get between all reinforcements and reinforcement windings located in the winding channel and may fill all spaces of the winding channel compactly and completely, thus perfectly enveloping the reinforcements. In the embodiments of FIGS. 3 and 4, the reinforcement 10 consists of homogeneous ribbon-like reinforcement steel on which sleevelike annular risers 2 are attached in the factory, similar to the embodiments of FIGS. 1 and 3. Again, the spacing sleevelike risers are provided on their outside with a wavy profile 3 and a radial groove 4. With both embodiments, the sleevelike risers 2 may be made of synthetic material and may be bonded in the factory to the periphery of reinforcement 1 or 10, respectively. FIGS. 6 through 8 show an embodiment where the reinforcement 11 consists of profiled ribbon-like reinforcement steel and where the spacing risers 6 are formed by the profile produced when rolling the reinforcement steel. In the embodiment example shown, the risers 6 have the shape of longitudinal ribs spaced apart in the lengthwise and transverse direction. On each wide side of the reinforcement, there are two rows of risers 6 which are staggered relative to one another. For example, reinforcement 11 may have a cross section area of 200 mm 2 where the longitudinal ribs 6 may protrude up to a rib height of, for example, about 2 mm beyond the periphery of the ribbon-like reinforcement steel. In this example, the arrangement of the longitudinal ribs is chosen so that the ribs cross section can be considered in its entirety as part of the reinforcement steel cross section taking the load. FIG. 8 shows the way several reinforcements 11 or reinforcement windings of the shown embodiment may be arranged in one reinforcement bundle or in one reinforcement winding. In this manner there are formed pass-through locations or paths 7 for a corrosion inhibitor or a compact material, e.g., cement mortar, to be subsequently introduced into the reinforcement bundle or into the reinforcement winding. These locations or paths 7 facilitate complete embedding of the reinforcements or reinforcement windings and a complete filling of all interstices. This complete filling up or enveloping of the reinforcements or reinforcement windings is supported by the fact that in the manufacture of the reinforcement 11 or the ribbon - like reinforcement steel through hot - rolling the width of the reinforcement fluctuates somewhat due to the different roller pressure caused by the profiling or the formation of the longitudinal ribs; as a result, a spacing effect also comes about at the narrow sides of the ribbon-like reinforcement steel. With the embodiment shown in FIG. 9, the reinforcement 12 again consists of a multistranded wire or a multistranded cable. However, in this embodiment the spacing risers 9 are formed by that part of the cross sections of two outer cable strands 13 and 14 protruding beyond the dashed-line peripheral circle which are stranded with the other strands 8 and 8' to form the seven-strand cable shown. The two outer wires 13 and 14 have a noticeably larger diameter than the other outer wires 8 of the stranded cable and, as components of the stranded cable, constitute spacer wires extending throughout its length. In the embodiment shown, also the center strand, or core strand 8' has such a larger diameter. However, this core strand might also have the same diameter as wires 8. It is only necessary that the spacer wires 13 and 14 have such a large cross section so that the outer part of their cross section protrudes sufficiently beyond the peripheral circle 12' of the stranded cable to form the spacing risers 9. These then protrude as helical ribs beyond the periphery of the stranded cable. With the reinforcement in accordance with FIG. 9, instead of the two spacing wires 13 and 14, only one such wire may be included. Also, the spacer wire (s), instead of a round cross section, may have an oval or other cross section. Thus, they may be square wires rounded off at the corners, for example. In any case, due to the arranging of one or several spacer wires in each reinforcement 12 with a multiplicity of reinforcements running closely next to one another or on top of one another in a reinforcement bundle or packet, there develop between them or their windings flow-through locations in the form of helical channels which, together with the grooves 15 between the strands, permit sufficient room for the flow-through of a corrosion inhibitor or compact material, e.g., injected mortar. According to FIG. 10, instead of one or more strands of enlarged cross section, there may be attached to a stranded-wire type reinforcement (denoted here by 16 and consisting of wires of identical cross section in the conventional manner) additional spacer wires 17' to form the spacing risers 17. They may have a smaller diameter than the other strand wires 8 and run in a groove 15 between two outer cable strands 8 so that each additional spacer wire 17' protrudes as helical rib beyond the circumference of stranded cable 16, indicated in FIG. 10 by dashed line 16'. The spacing effect of the additional spacer wires 17 otherwise is similar to that of the oversize spacer wires 13 and 14 of FIG. 9. Also, the additional spacer wires 17 of FIG. 10 may have any profile desired. In particular, the cross section of wires 17 may be adapted to the shape of the groove 15 existing between the outer cable strands 8. As a result, the spacer wires 17 get a better hold of the stranded cable. With a stranded-cable type reinforcement and with a reinforcement made of rod- or ribbon-like reinforcement steel, e.g., with a ribbon steel reinforcement 20 in accordance with FIG. 11, the spacing risers 18 may also be formed by an additional spacer wire 19 which is wound around the reinforcement in such a way that its windings are spaced apart. Again, the spacer wire 19 may have a round cross section or any other profile, and may have been fastened to reinforcement 20 in the factory by mere winding around or by welding or in any other manner. Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention, and therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

A reinforcement arrangement of high-tension resistant steel for prestressed concrete members or buildings, in which rigidly attached projecting portions protrude substantially from the periphery of the reinforcement. Passages between the projecting portions and the periphery of the reinforcement permit embedding of the reinforcement in the form of a bundle or packet consisting of one or several reinforcements, in a predetermined material which is subsequently introduced. Such material may be in the form of a corrosion inhibitor, or compact substance such as cement mortar. The reinforcement may be in the form of a multistrand wire or cable in which the projecting portions are annular and located at predetermined intervals along the length of the reinforcement. The projecting portions may be of iron or steel, as well as plastic material.

FIELD [0001] The present disclosure relates to vehicle heating, ventilation, and air cooling systems, and particularly to a rib maze that prevents airflow along a wall. BACKGROUND [0002] This section provides background information related to the present disclosure, which is not necessarily prior art. [0003] Motor vehicle heating, ventilation, and air cooling (HVAC) systems typically include an HVAC casing with an evaporator and a heater core housed therein. In a heating mode, airflow that has passed into the HVAC casing through the evaporator, which is often deactivated, is directed through the heater core by a temperature mixing door arranged in parallel to the heater core. In a cooling mode, the evaporator is activated and the control door is positioned such that cooled airflow that has passed through the evaporator is directed away from the heater core. A secondary temperature mixing door may be placed between the evaporator and the heater core so that in the cooling mode a positive airflow seal prevents airflow from entering the heater core chamber and becoming heated. To reduce costs, simplify operation, and increase operational reliance of the HVAC system, it would be desirable to eliminate the control door between the evaporator and the heater core. SUMMARY [0004] This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. [0005] The present teachings provide for an airflow deflector including a plurality of spaced apart ribs each extending in a longitudinal direction between a first end and a second end thereof that is generally perpendicular to an airflow stream to be deflected by the airflow deflector such that the plurality of spaced apart ribs induce recirculations of the airflow stream between neighboring ones of the plurality of spaced apart ribs to increase air pressure at an entrance to areas defined between neighboring ribs and restrict the airflow from flowing past the plurality of spaced apart ribs. [0006] The present teachings further provide for an HVAC system for a motor vehicle including an evaporator, a heater, and a plurality of spaced-apart deflector ribs that are between the evaporator and the heater. The deflector ribs are configured to direct airflow away from the heater. [0007] The present teachings also provide for an HVAC system for a motor vehicle including an evaporator, a heater, and a plurality of spaced-apart deflector ribs. The deflector ribs are between the evaporator and the heater, and extend in a direction generally perpendicular to airflow to be deflected. [0008] Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. DRAWINGS [0009] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. [0010] FIG. 1 is a side view of an HVAC system according to the present teachings; [0011] FIG. 2 is a close-up view of area 2 of FIG. 1 ; [0012] FIG. 3 illustrates airflow through the HVAC system of FIG. 1 . [0013] Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. DETAILED DESCRIPTION [0014] Example embodiments will now be described more fully with reference to the accompanying drawings. [0015] With initial reference to FIG. 1 , a heating, ventilation, and air cooling (HVAC) system is illustrated at reference numeral 10 . The HVAC system 10 includes an evaporator 12 and a heater core 14 . The evaporator 12 includes a first side 16 and a second side 18 , which is opposite to the first side 16 . The heater core 14 includes a first side 20 and a second side 22 , which is opposite to the first side 20 . The second side 18 of the evaporator 12 faces the first side 20 of the heater core 14 . [0016] The HVAC system 10 further includes a first door or air mix door 24 , a second door 26 , a face outlet 28 , and a foot outlet 30 . The first and second doors 24 and 26 are illustrated as rotary doors, but can be any suitable type of door to direct and/or restrict airflow. With respect to the direction of airflow through the evaporator 12 , the first door 24 succeeds the evaporator 12 and is in parallel to the heater core 14 . The second door 26 is proximate to the face outlet 28 and the foot outlet 30 . [0017] The first door 24 is movable between a first position 24 a and a second position 24 b . In the first position, which is illustrated in FIG. 1 , the first door 24 extends generally between the evaporator 12 and the heater core 14 to force airflow to pass through the heater core before exiting to the face and foot outlets 28 and 30 . In the second position, the first door 24 blocks airflow from the heater core 14 allowing it to go directly to the face and foot outlets 28 and 30 . [0018] The second door 26 is also movable between a first position 26 a and a second position 26 b . FIG. 1 illustrates the second door 26 in the first position 26 a to block airflow to the face outlet 28 , thereby permitting airflow through the foot outlet 30 . In the second position 26 b , the second door 26 is arranged to block airflow to the foot outlet 30 , thereby permitting airflow through the face outlet 28 . [0019] Between the evaporator 12 and the heater core 14 is a diverter 40 , which is generally a raised surface of HVAC housing or case 42 at a base 44 thereof. With continued reference to FIG. 1 and additional reference to FIG. 2 , the diverter 40 includes a diverter apex 46 and a diverter face 48 , which extends between the diverter apex 46 and the base 44 . The diverter face 48 generally faces the second side 18 of the evaporator 12 . [0020] Also between the evaporator 12 and the heater core 14 are a plurality of deflectors 50 a - 50 f , which generally take the form of deflector ribs. As illustrated, six deflector ribs 50 a - 50 f are included. Any suitable number of deflector ribs 50 a - 50 f can be included, however. Each deflector rib 50 a - 50 f generally includes an elongated portion with a first end 52 a - 52 f and a second end 54 a - 54 f that is opposite to the first end 52 a - 52 f . One or more of the deflector ribs 50 a - 50 f can include a transverse portion 56 , such as at the second end 54 a - 54 f . The transverse portion 56 extends generally transverse or perpendicular to the rest of the deflector rib 50 a - 50 f that the transverse portion 56 is associated with. As illustrated, deflector rib 50 a includes the transverse portion 56 at the second end 54 a . Such a transverse portion 56 can be provided at any location where the longitudinal portion of the ribs 50 a - 50 f between the first end 52 a - 52 f and the second end 54 a - 54 f is not entirely sufficient to deflect airflow. [0021] The deflector ribs 50 a - 50 f can be arranged in any suitable manner. For example, the deflector ribs 50 a - 50 f can be arranged such that they extend lengthwise between the first end 52 a - 52 f and the second end 54 a - 54 f in a direction generally perpendicular to a main airflow stream A, as illustrated in FIG. 2 for example. The deflector ribs 50 a - 50 f can be arranged in any suitable orientation relative to one another in order to extend generally perpendicular to the main airflow stream A, such as along a curved line B, which is illustrated in FIG. 2 and extends between the heater core 14 and the evaporator 12 . First deflector rib 50 a is arranged closest to the heater core 14 , furthest from the evaporator 12 , and furthest from the base 44 of the HVAC case 42 . Sixth deflector rib 50 f is arranged furthest from the heater core 14 , closest to the evaporator 12 , and closest to the base 44 . The deflector ribs 50 a - 50 f can have varying lengths. For example, the fourth deflector rib 50 d can be shorter than the neighboring third and fifth deflector ribs 50 c and 50 e . The deflector ribs 50 a - 50 f are generally arranged staggered or offset with respect to each other along the curved line B. For example, the third deflector rib 50 c can be further offset from the line B than the second or fourth deflector ribs 50 b and 50 d. [0022] Operation of the HVAC system 10 in a maximum heat mode will now be described. Airflow is directed through the evaporator 12 , which can be deactivated. Airflow enters the evaporator 12 at the first side 16 , and exits the evaporator 12 at the second side 18 . In the maximum heat mode, the first door 24 is arranged in the first position 24 a illustrated in FIG. 1 , such that all airflow passing through the evaporator 12 is directed to the heater core 14 . With the first door 24 in the first position 24 a of FIG. 1 , the pressure between the evaporator 12 and the heater core 14 drops, thereby further forcing airflow from the evaporator to the heater core 14 . The deflector ribs 50 a - 50 f are orientated such that they extend generally parallel to the direction of airflow to the heater core 14 when the first door 24 is at the first position 24 a of FIG. 1 , thereby permitting airflow to pass to and through the heater core 14 to heat the airflow, with only a small restriction. [0023] In a cooling mode, the evaporator 12 is activated and the first door 24 is rotated to the second position 24 b , in which airflow is free to flow directly from the evaporator 12 to the face and foot outlets 28 and 30 without passing through the heater core 14 . The diverter 40 will direct airflow from the evaporator 12 away from the heater core 14 and towards the face and foot outlets 28 and 30 . Furthermore, air pressure between the evaporator 12 and the heater core 14 will be less than that at and behind the heater core 14 , thereby forcing airflow away from the heater core 14 and towards the face and foot outlets 28 and 30 . To prevent the airflow from being warmed by the heater core 14 , it is desirable to keep the airflow, such as airflow A of FIG. 2 , as far away from the heater core 14 as possible. The deflector ribs 50 a - 50 f direct airflow A away from the heater core 14 due to their arrangement and orientation. [0024] The staggered arrangement of the deflector ribs 50 a - 50 f and the general arrangement of the deflector ribs 50 a - 50 f perpendicular to the main airflow stream A creates a series of small channels therebetween that induce small air recirculations, as illustrated in FIG. 3 , between the ribs 50 a - 50 f as airflow A moves along the deflector ribs 50 a - 50 f . The recirculations increase the pressure at the second ends 54 a - 54 f of the ribs 50 a - 50 f , which substantially reduces the amount of airflow to the heater 14 . As a result, the airflow A is forced away from the heater core 14 , thereby preventing the airflow A from being warmed by the heater core 14 when the HVAC system 10 is in a cooling mode. [0025] Although the deflector ribs 50 a - 50 f are described as being used with the HVAC system 10 , the ribs 50 a - 50 f can be provided at any suitable location and can be used with any suitable device, process, machine, manufacture, or composition to direct airflow away from a surface. The position and orientation of the ribs 50 a - 50 f can be customized according to the particular application. For example, any suitable number of the ribs 50 a - 50 f can be provided with any suitable spacing, length, and orientation such that the ribs 50 a - 50 f extend generally perpendicular to an airflow to create a series of small channels along the airflow stream that induce small airflow recirculations between neighboring ribs 50 a - 50 f . The airflow recirculations increase the pressure at the entrances of the channels (such as at the second ends 54 a - 54 f of the ribs 50 a - 50 f ), which reduces airflow past or through the channels. Any one or more of the ribs 50 a - 50 f can be provided with the transverse portion 56 at any location where the longitudinal portion of the ribs 50 a - 50 f between the first end 52 a - 52 f and the second end 54 a - 54 f is not entirely sufficient to deflect airflow [0026] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

An airflow deflector including a plurality of spaced apart ribs each extending in a longitudinal direction between a first end and a second end thereof that is generally perpendicular to an airflow stream to be deflected by the airflow deflector such that the plurality of spaced apart ribs induce recirculations of the airflow stream between neighboring ones of the plurality of spaced apart ribs to increase air pressure at an entrance to areas defined between neighboring ribs and restrict the airflow from flowing past the plurality of spaced apart ribs.

PRIORITY CLAIM This application is a continuation of U.S. Ser. No. 14/194,193, filed Feb. 28, 2014, now U.S. Pat. No. 9,409,193 which is a divisional of U.S. Ser. No. 12/897,362, filed Oct. 4, 2010, now U.S. Pat. No. 8,668,399 which is a continuation of U.S. Ser. No. 11/563,791, filed Nov. 28, 2006, now U.S. Pat. No. 7,815,384, which is a continuation of U.S. Ser. No. 11/003,449, filed Dec. 6, 2004, now U.S. Pat. No. 7,144,170, which claims priority to U.S. Provisional Application Ser. Nos. 60/551,200, filed Mar. 8, 2004 and 60/533,973, filed Jan. 2, 2004, the entire contents of each of which are hereby incorporated by reference. BACKGROUND OF THE INVENTION Field of the Invention This invention relates to multi-component dispensing and mixing systems for paints and coatings. More particularly, the present invention relates to devices and methods for packaging, mixing, and dispensing multi-component paints. Related Art U.S. Pat. No. 5,249,709 discloses cartridges for dispensing reactive materials in predetermined ratios. U.S. Pat. No. 5,072,862 discloses static flow mixers for use in dual cartridges, U.S. Pat. No. 4,538,920 discloses a dual cartridge with a static mixer in the nozzle. U.S. Pat. No. 4,767,026 discloses dual cartridge dispensing and mixing apparatus. U.S. Pat. No. 6,135,631 discloses a static mixer and nozzle for a multiple component dispensing cartridge having at least two cylinders. U.S. Pat. No. 5,535,922 discloses a caulking gun dispenser device, which allows one to use a multi-component cartridge dispenser in a regular caulking gun. U.S. Pat. No. 5,875,928 discloses a two-plunger dispensing gun suitable for mixing and discharging two-component compositions. U.S. Pat. No. 6,244,740 discloses a mixer for multi-component cartridges. U.S. Pat. No. 3,166,221 discloses a plastic, double-tube dispensing container. U.S. Pat. No. 3,828,980 discloses a dual cartridge dispenser. U.S. Pat. No. 6,601,782 discloses a disposable spray nozzle assembly. Background of the Technology The use of high solids coatings is becoming increasingly popular. In the 1970's, regulatory bodies such as the Environmental Protection Agency (EPA) and the California Air Resource Board (CARB) began to scrutinize the paint and coating industries to reduce the amount of Volatile Organic Compounds (VOCs) released into the atmosphere. The regulatory bodies discovered that the solvents contained within paints were contributors to air pollution. The VOCs, which are released as the solvent evaporates from a painted surface during cure, react with nitrogen oxides to form ozone. As a result, the Clean Air Act (CAA) was developed by the EPA to regulate policies concerning the release of large amounts of VOCs into the atmosphere in an attempt to prevent further damage to the environment. Each year coating application regulations reduce the amount of allowable VOC emissions released from coatings into the atmosphere. The military has begun specifying traditional solvent-based coatings and high solids, edge retentive coatings for construction and repair. These coatings were the government's solution to service life extension and reduced life cycle cost goals while at the same time addressing the tightening regulations. However, with the introduction of this new coating technology, new processes and handling requirements, unfamiliar to painters, were also introduced. Multi-component, high solids paints cure by a chemical reaction that creates heat after mixing. With the small amount of solvent content, VOCs are greatly reduced, and the coatings provide a higher level of performance. These types of coatings have a much higher viscosity than traditional solvent-based systems, making them very difficult to apply. If the coatings are manually mixed and applied, the pot life of the mixture is shortened dramatically, often as short as 30 minutes and some measured on the order of seconds. Application environment and ratio control have more effect on these coatings than traditional coatings. Pot life, viscosity and curability are all dependent at least in part on temperature and humidity. Painters and supervisors need to continuously monitor these variables to produce the best product, which leads to increased costs. SUMMARY OF THE INVENTION The present invention solves the above problems, and others. One embodiment of the present invention provides a device for applying a coating, which includes: a multi-component cartridge, a static mixing nozzle in fluid communication with the cartridge, and at least one paint applicator selected from the group including a roller, a brush, and an angled spray tip, in fluid communication with the nozzle. Another embodiment of the invention provides a method, which includes applying a coating to a surface with the above-described device. Another embodiment of the invention provides a method, which includes applying a non-skid coating to a surface with the above-described device. BRIEF DESCRIPTION OF THE FIGURES The following description will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings some embodiments which are presently preferred, it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown. FIG. 1 shows the general parts of a preferred embodiment of the present invention. FIG. 2 shows the general parts of a preferred embodiment of the present invention. FIG. 3 shows the general parts of a preferred embodiment of the present invention. FIG. 4 shows the general parts of a preferred embodiment of the present invention. FIG. 5 shows the general parts of a preferred embodiment of the present invention, FIG. 6 shows the detail of a preferred embodiment of the present invention. FIG. 7 shows the detail of a preferred embodiment of the present invention. FIG. 8 shows the detail of a preferred embodiment of the present invention. FIG. 9 shows the detail of a preferred embodiment of the present invention. FIG. 10 shows the detail of a preferred embodiment of the present invention. FIG. 11 shows a preferred embodiment of the present invention. FIG. 12 shows a preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION Various other objects, features, and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description of the invention, which is not intended to be limiting unless otherwise indicated. The invention provides a multi-component industrial paint packaging system for use in simultaneously dispensing, mixing, brushing, rolling or spraying liquid coatings in one easy step. Preferably, the coatings are multi-component, reactive, high-solids low-VOC paints. More preferably, the coatings are multi-component, reactive, high-solids low-VOC marine, military, and industrial paints. The present invention desirably allows one to dispense, mix, roll, or spray two component marine and industrial paints in one continuous step without having to pre-mix either component. It also allows dispensing of the exact amount of marine, military, and industrial paints while reducing or eliminating the mixer's or painter's exposure to unnecessary hazardous materials, reduces the amount of hazardous waste in application, disposal and clean up, and reduces the amount of VOC's released into the environment. The invention is particularly suitable for large-scale industrial applications because it enables significant and unexpected savings of both material and labor, which translates into significant cost savings. The invention eliminates the need for packaging paints in one and five gallon cans, eliminates the need to open and premix paints, eliminates the need to manually pre-measure paints into exact ratios for use, significantly reduces waste and generation of excess paint associated with conventional methods, and provides a direct delivery method for marine and industrial paint by rolling, brushing, spraying, or power rolling the paint onto the surface to be painted. For example, in the course of industrial or commercial painting on a large scale, the paint composition is often continually transferred from large containers to smaller containers to avoid mixing more paint than needed and to reduce the carry burden of the individual painter. FIG. 1 shows one preferred embodiment of the present invention. This embodiment includes a power roller, and the reactive paint components are desirably kept separate from one another and away from the atmosphere until immediately before use, when they are intimately mixed and fed to the roller for direct application. FIG. 1 shows a manual dispensing gun 2 and multi-component cartridges 1 and 1 a . The cylindrical multi-component cartridges 1 , 1 a have respective cross sectional volumes that are proportional to predetermined mixing ratios. Each cartridge preferably contains one component of a multi-component coating, and thus the respective reactive components (for example a coating resin and catalyst) remain separate until mixing through a static mixer nozzle 9 , and dispensed through a roller 7 , which in this embodiment is a perforated or bleed through roller. In this embodiment, a manual dispensing gun 2 is shown. During operation, piston rods 3 attached to piston plates 3 a exert a force sufficient to push the piston plates 3 a and cartridge piston seals 4 , 4 a simultaneously through the multi-component cylindrical cartridges 1 , 1 a , which force ejects their respective contents, the reactive components. The reactive paint components flow through a common discharge nozzle 8 and into the static mixing nozzle 9 , where they contact one another. The reactive components are intimately mixed with one another as they flow through the static mixing nozzle 9 . In this embodiment, manual dispensing is initiated and controlled by a trigger system 5 . The dispensing gun optionally has a handle 2 a for the user to hold onto the dispenser while rolling the coating onto the work surface. The mixed paint is fed from the static mixing nozzle 9 into a discharge tube 10 that feeds the mixed coating material into the roller 7 for direct application to the work piece. The manual dispensing gun 2 has a support arm 6 attached to it, which supports the roller attachment 7 . The reactive components are ejected from their respective cartridges into the static mixing nozzle 9 in a ratio determined by the respective cross-sectional areas of the cartridges I and I a. In this way, the reactive components are thoroughly mixed and in the correct proportion, and thus two sources of potential error are avoided, in contrast with conventional mixing and formulating procedures. In addition, in one preferred embodiment, any or all of the roller 7 , static mixer 9 , and discharge tube 10 are disposable, being the only components that contact the mixed paint, so time-consuming and wasteful solvent cleaning is not necessary. The cartridges I and I a may either be resealed for future use if some remains or, if none remains, they may be disposed of as well. Another preferred embodiment of the present invention is illustrated in FIG. 2 , wherein the reactive paint components are ejected from the multi-component cartridges 1 , 1 a with pneumatic or hydraulic force through individual dispensing apertures 11 and into and through hoses 12 to a remote roller applicator 17 that includes a power roller-type system for direct and continuous rolling. In this embodiment, pneumatic or hydraulic pumps 13 drive the piston rods 3 , which apply continuous pressure on the cartridge piston seals 4 , 4 a for a continuous supply of paint to the roller 7 . The pneumatic pump has an air regulator 14 that regulates the air pressure applied to the piston rods. The twin hoses 12 attach to a coupler 15 . The coupler 15 has a securing nut 16 to attach it and thus the hoses 12 to the remote roller applicator 17 . The length of the hoses 12 may vary according to need. The remote roller applicator 17 has a trigger 18 that allows an operator to activate the pumps 13 and dispense and apply the mixed paint on demand and as needed. In the remote roller applicator, the reactive paint components are mixed in the static mixer 9 , and the thus-mixed paint proceeds, still under pressure from the pumps 13 , into a discharge tube 10 and to the roller 7 for direct application to the workpiece. The remote roller applicator 17 includes a support arm 6 supports the roller 7 in place during application. Preferably, the roller 7 , discharge tube 10 , and static mixer are each independently removable and/or disposable. One preferred embodiment is illustrated in FIG. 3 , wherein pneumatic or hydraulic force to dispensing plugs for direct air assisted low pressure spray application of marine and industrial paints. The cartridges 1 and 1 a are pressurized by pneumatic or hydraulic force via pumps 13 , piston rods 3 and piston plates 3 a , which apply continuous pressure on the cartridge piston seals 4 , 4 a , and the reactive components are pumped through hoses 12 . Since each of the reactive components remains separate from the other in its hose there is no danger of curing and blocking the hoses 12 , and thus the hoses 12 may have any length as appropriate for remote painting. The pneumatic or hydraulic pump 13 has an air regulator 14 that regulates the air pressure. Hoses 12 attach to the cartridges 1 , 1 a by securing nuts 19 to individual dispensing apertures 11 , which are illustrated in FIG. 2 . The other end of the hoses 12 attach to a coupler 15 , which attaches in turn to a handheld remote spray applicator gun 20 . The remote spray applicator gun 20 has a trigger 18 that allows the operator to dispense the mixed paint on demand and as needed. The remote spray applicator gun 20 includes a disposable static mixer 9 , and a spray tip 21 that uses regulated air for atomization of the mixed paint to spray-apply the paint to a substrate. The regulated air for ejecting and atomizing the mixed paint is supplied by a hose 22 that is attached to the spray tip 21 and is controlled by the operator when he or she pulls the trigger 18 . In an alternative embodiment of the one described, a manual dispensing gun 2 is used to pump the reactive components from individual apertures through hoses 12 and on to the remote spray applicator gun. One preferred spray tip 21 is available from V.O. Baker, Spray Tip Nozzle Manifold Part No. SPRYNZZL004-VOB. An angled spray tip 21 is preferred in view of reaching hard-to-access areas such as stiffeners near the hull of a ship. Such spray tips have an angle between the spray direction and the paint feed direction. Preferable angles range from 15 to 90 degrees and include 15, 25, 35, 45, 55, 60, 75, 85 and 90 degrees. The spray tip 21 may attach to the nozzle by any conventional fluid connection including Luhr-Lock, Bayonet, screw on, retaining nut, snap fit, friction fit, and the like. Friction fit is preferred. In one embodiment of the invention, a flexible hose connects the spray tip 21 and the static mixer nozzle 9 . In such an embodiment, the hose 22 remains attached to the spray tip 21 , but is suitably lengthened to accommodate the length of the flexible hose between the spray tip 21 and the static mixer nozzle 9 . In this embodiment, either a manual dispensing gun 2 or a pneumatic or hydraulic dispensing gun 38 may be used, and the remote spray applicator gun 20 may also be used. The operator may easily hold the spray tip 21 , the flexible hose, and the hose 22 in one hand for paint application, and may initiate and control the liquid coating flow with the remote spray applicator gun 20 in the other. In this embodiment, the spray tip 21 may or may not be angled. This desirably allows the painter nearly complete freedom of movement, in contrast with bulky and awkward conventional application techniques. Heretofore, such freedom of movement and ability to spray apply was unknown. The flexible hose may have any length so long as the dwell time of the mixed paint in the flexible hose does not exceed the pot life. This flexible hose may be suitably disposable. FIG. 4 illustrates one preferred embodiment of the invention, which includes a manual dispensing gun 2 , multi-component cartridges 1 , 1 a , a static mixer nozzle 9 , and a brush applicator 23 . The trigger 5 is squeezed by the operator, forcing the piston rods 3 and piston plates 3 a and thus the piston cartridge seals 4 and 4 a along the length of the cartridges 1 , 1 a . The reactive paint components are ejected through common discharge nozzle 8 into the static mixer 9 , where they are thoroughly mixed. The thus-mixed paint is fed to the brush 23 , where it may be brush-applied to the work surface. A support arm, similar to the support arm 6 shown in FIGS. 1 and 5 , may be optionally attached to the dispensing gun 2 and the brush 23 to support the brush 23 . Of course, the brush 23 and mixing nozzle 9 may be attached to a hydraulic or pneumatic pump 13 or a hand-held pneumatic or hydraulic dispensing gun 38 instead of the manual dispensing gun 2 . In addition, the brush 23 and mixing nozzle 9 may be combined in a separate remote assembly similar to the remote spray applicator gun 20 connected by dual hoses 12 such as described herein. The mixed paint may be applied from the static mixing nozzle onto an outer surface of the brush bristles, or the mixed paint may be applied to an interior portion of the brush bristles via one or more hollow passages leading from the outlet of the static mixing nozzle through the body of the brush 23 and into the interior part of the bristles. In the present context, either alternative is considered to be a fluid connection. The latter alternative, using one or more hollow passages through the brush 23 , is preferred. The brush 23 and static mixing nozzle 9 are each independently removable and/or disposable. FIG. 5 illustrates one preferred embodiment of the invention, which includes a manual dispensing gun 2 , multi-component cartridges 1 , 1 a , a static mixer nozzle 9 , a roller 7 , and a roller coater 24 . In this embodiment, the mixed paint emerging from the static mixer 9 is fed through the roller coater 24 , which applies the mixed paint onto the exterior portion of the roller 7 . The operator then rolls the paint onto the work surface with the roller 7 . The roller coater 24 and roller 7 are stabilized and supported by the support arm 6 . Of course, the roller coater 24 and roller 7 may be attached to a hydraulic or pneumatic pump 13 or a hand-held pneumatic or hydraulic dispensing gun 38 instead of the manual dispensing gun 2 . In addition, the roller coater 24 and roller 7 and mixing nozzle 9 may be combined in a separate remote assembly similar to the remote brush applicator 17 connected by dual hoses 12 such as described herein. In the context of the present invention, both the power roller type assembly using a perforated roller and the roller coater type assembly, such as described herein, are considered fluid connections. The former alternative, using the power roller assembly, is preferred. FIGS. 6, 7 and 8 illustrate preferred multi-component paint cartridges 1 , 1 a in more detail. Cartridges 1 , 1 a include parallel reservoirs 26 and 27 having cartridge piston seals 4 and 4 a sealing one end of each, respectively. Apertures 28 and 29 are formed in ends of reservoirs 26 and 27 , respectively, which oppose cartridge piston seals 4 and 4 a . A discharge nozzle 8 is received in apertures 28 and 29 , and closed by a nose plug 32 removably inserted therein. A retaining nut 33 threads onto discharge nozzle 8 , holding plug 32 in position. Nut 33 is sealed by a disk 35 . The reactive paint components in reservoirs 26 and 27 are mixed in specific ratios according to the respective reservoir volumes and cross sectional areas to provide a curable paint composition. Depending upon the material employed, various ratios are required. FIG. 6 illustrates a preferred multi-component paint cartridge with reservoirs 26 and 27 having a 1:1 ratio. FIG. 7 illustrates a preferred multi-component paint cartridge with reservoirs 26 and 27 having a 2:1 ratio, FIG. 8 illustrates a preferred multi-component paint cartridge with reservoirs 26 and 27 having a 4:1 ratio. One skilled in the art will understand that reservoirs 26 and 27 can be fabricated in various sizes to accommodate the necessary ratio of reactive components. FIG. 9 illustrates the cross-section of a preferred static mixer 9 with cap 40 . Mixing elements 41 are shown. The terms, I.D., O.D., A, and L represent inner dimension of the main tube, outer dimension of the main tube, outlet inner dimension and length, respectively. FIG. 10 illustrates the cross section of a preferred static mixer 9 without cap 40 . Mixing elements 41 are shown. The inlet 42 is at the upstream side relative to fluid flow, and receives the reactive components. The reactive components contact and are mixed by the elements as the components traverse the length of the mixer 9 , until they exit in the mixed paint form from the outlet 43 at the downstream end of the static mixer 9 . In operation, removal disc 35 and nose plug 32 are removed, providing an unobstructed passage for the reactive components from reservoirs 26 and 27 though apertures 28 and 29 and discharge nozzle 8 . The static mixer nozzle is attached to the discharge nozzle 8 . The reactive paint components are forced from reservoirs 26 and 27 and through apertures 28 and 29 by the movement of cartridge piston seals 4 and 4 a , which are sealingly and slidably disposed within the reservoirs 26 and 27 . The ejection of the components is accomplished by the use of a pneumatic or hydraulic dispensing gun 38 or a manual dispensing gun 2 . FIGS. 11 and 12 show other embodiments of pneumatic or hydraulic and manual dispensing guns, respectively. The dispensing gun depresses cartridge piston seals 4 and 4 a with piston rods 3 equally to eject the correct proportions of each reactive paint component. The piston plug 39 sometimes known as a bleeding pin or a burping pin is optionally present in the cartridge piston seals 4 , 4 a and is useful when bleeding gas or air out of the reservoirs 26 and 27 when they are filled with reactive component liquids such as paint, resin, or catalyst, for example. The multi-component cartridge 1 and 1 a is not particularly limiting. Suitable cartridges are described, for example, in U.S. Pat. No. 5,249,709. Other suitable cartridges may be obtained commercially from Plas-Pak Industries, Norwich Conn. The cartridges 1 and 1 a may either have a side-by-side construction, or a cartridge-within-a-cartridge construction. Examples of the latter are disclosed in, e.g., U.S. Pat. No. 5,310,091. The respective cartridges 1 and 1 a may have a permanent connection between them, or they may be separable, for example by one or more snap or similar connections. In one embodiment, the cartridges 1 and 1 a are connected to one another by a snap connection near the common discharge nozzle 8 . The cartridges 1 and 1 a may be made of any suitable material, such as polyethylene or nylon. Nylon is preferred. Individual reservoir 26 and 27 volumes in the cartridges 1 and 1 a may each independently range from 50 to 3000 ml, which range includes 50, 75, 100, 150, 250, 500, 750, 1000, 1250, 1500, 1750, 2000, 2250, 2500, 2750, and 3000 ml, and any combination thereof. The reservoirs 26 and 27 in the cartridges may each independently have any suitable cross sectional area, in accordance with the formulation requirements of the reactive components. The cross sectional area ratio may range from 1:1 to 1:20, which range includes 1: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20 as appropriate. Ratios of 1:1, 1:2, 1:4 are preferred. The present invention is particularly useful for applying liquid coatings such as reactive two-component solvent-based coatings, edge-retention coatings, anti-corrosive coatings, high-solids coatings, low VOC coatings, Chemical Agent Resistant Coatings (C.A.R.C. paints), non-skid coatings, and the like, including but not limited to topcoat and/or primer coatings of polyurea, polyaspartic, epoxy, acrylic, silicone, polyester, polyurethane, polyamide, bisphenol A epoxy, bisphenol F epoxy, epoxy-polyamide, epoxy-polyamine, epoxy-ketamine, non-skid, aggregate-containing, aluminum oxide-containing, silica-containing, and the like. These coatings are suitable in a variety of marine, military, off shore, petrochemical, automotive, transportation, rail, aerospace, and industrial applications. Other suitable application examples include without limitation ship construction and repair of tanks, ship structure, weapon systems, military transport vehicles, weapons, missiles, rail car repair, industrial transpiration equipments, pleasure craft and commercial ship construction and repair, aerospace systems, off shore platforms and markings, airplane maintenance, facilities and structures, industrial machinery and equipments, lawn and garden equipments, rigid container and closure coatings, and food processing equipment coatings. Marine and military applications are preferred. The coating compositions are supplied as two or more separate components, usually referred to as the base and the curing agent. When these components are mixed, immediately before use, a chemical reaction occurs. These materials therefore have a limited ‘pot life’ before which the mixed coating must be applied. The polymerization reaction continues after the paint has been applied and after the solvent has evaporated to produce a densely cross linked film which can be very hard and has good solvent, mechanical, and chemical resistance. There are also chemically resistant paints often referred to as blast primers, shop primers, temporary primers, holding primers, and the like. These types of primers are more preferably used on structural steelwork, immediately after blast cleaning, to maintain the reactive blast cleaned surface in a rust free condition until final painting can be undertaken. The reactive components, for example, resin and catalyst, or base and curing agent as more commonly referred to, may be formulated in proportions known to those of skill in the art. Preferred coatings include bisphenol A epoxies and bisphenol F epoxies, with one or more polyamide, polyamine, and ketamine being preferred as catalyst. Preferred curing agent: base ratios range from 1:1 to 1:20, with 1:1, 1:2, 1:3 and 1:4 being preferred. High-solids, low solvent or low VOC coating compositions have solids content approaching 100% by weight of the coating. The solids content ranges from more than 80% to 100% by weight, which includes 85, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 995, less than 100, and 100% by weight. The VOC or solvent content approaches zero, ranging from typically less than 20% by volume to zero percent, which includes 19, 17, 15, 13, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0.5, greater than zero, and zero percent by volume. Coatings having zero to 6% VOC's by volume are preferred. Coatings having 94 to 100% solids by weight are preferred. The present invention is also suitable for high-VOC coatings, having solvent contents of 50 to 94% solids by weight. This range includes 50, 55, 60, 62, 64, 66, 68, 70, 75, 80, 85, 90, and 94% solids by weight. These types of coatings are particularly suited for application to antennas, specialty coatings, and the like. A preferred example of such high-VOC liquid coatings is MlL-DTL-24441. The preferred coating compositions have short pot lives upon mixing the reactive components, ranging from 3 hours or less to 0.25 hours, which range includes 2.75, 2.5, 2.25, 2, 1.75, 1.5, 1.25, 1, 0.75, 0.5, and 0.25 hours. One or more than one coat may be applied. The coating compositions may contain one or more pigments, inhibitive agents and/or pigments, and non-inhibitive agents and/or pigments, microballoons, and the like. One embodiment of the present invention provides a method of applying a non-skid coating composition, which includes applying to a surface an epoxy composition that contains an aggregate, such as aluminum oxide or silica, with the paint dispensing system described herein. In this embodiment, one of the cartridges 1 and 1 a contains a hardener, and the other contains an epoxy resin and the aggregate. The reactive hardener and epoxy resin with the aggregate are combined and mixed in the static mixer nozzle 9 , and applied. A desirably tough non-skid surface results. In another embodiment of the invention, a one component composition is applied using the paint dispensing system described herein. In this embodiment, a reactive two component paint is not used, and instead a one-component composition is contained in both cartridges. This embodiment provides the ability to produces a superior conventional coating from a convenient packaging system, and reduces waste and cleanup. One embodiment of the invention includes a cartridge 1 , 1 a that optionally has hermetically sealed dispensing and/or filling ends to prevent marine and industrial paints from leaking during handling, shipping and storage. The hermetic seal may be foil, plastic, or a combination thereof. Preferably, the hermetic sealing material is chemical resistant and forms a gas and liquid tight seal on either or both of the filling ends 25 (after being filled with one reactive liquid of the multi-component coating, cartridge piston seals 4 , 4 a , inserted, and degassed through piston plugs 39 ) and the aperture end 28 , 29 of the multi-component cartridges. The hermetic seals at the aperture end of the cartridge may complement or replace the removal disc 35 and nose plug 32 if desired. Static mixing nozzles 9 are not particularly limited so long as they progressively divide and recombine to thoroughly mix the reactive components of the coating. As the reactive components traverse the length of the static mixing nozzle 9 , the number of mixing “folds” experienced by the fluid may be calculated as 2 , wherein n is the number of mixing elements present. Some examples of static mixing nozzles 9 are described, for example, in U.S. Pat. Nos. 4,850,705, 4,767,026, and 4,538,920. Suitable static mixers may also be obtained commercially from Plas-Pak Industries, Norwich Conn.; and V.O. Baker Co., Mentor OR The size of the static mixing nozzles 9 may suitably range from ⅛″ to 1½″ or 1 to 25 mm as appropriate, which includes ⅛″, 3/16″, ¼″, 5/16″, ⅜″, 7/16″, ½″, 9/16″, ⅝″, 1 1/16″, ¾″, 13/16″, ⅞″, 15/16″, 1″, 1¼″, 1½″ and any combination thereof. Preferably, a step-down static mixer is used, wherein the I.D. changes from ⅜″ to ¼″ as one nears the outlet. Such step-down static mixing nozzles are available from Plas-Pak Industries, Norwich Conn. The static mixing nozzle 9 may attach to the common discharge nozzle 8 on the cartridges 1 and 1 a with any suitable connection such as screw threads, Luhr-lock, lock-on retainer nut, bayonet tip, snap fit, frictional fit, and the like. The dispensing gun is not particularly limited so long as it is capable of applying sufficient force to the cartridge piston seals 4 and 4 a to move the reactant components from their respective cartridges 1 and 1 a through the static mixing nozzle 9 and on to the applicator roller 7 , sprayer 21 , or brush 23 . The dispensing gun may be of the manual type 2 , or the pneumatic or hydraulic type 38 . The manual type may apply force through a clutch bar, screw, ratchet or similar mechanism connected to the squeeze trigger and handle assembly 5 . One suitable manual dispensing gun is the NEWBORN 530™, manufactured by Newborn Bros. Other suitable manual guns are described, for example, in U.S. Pat. No. 5,875,928. The pneumatic type of dispensing gun is preferably regulated and air driven. Preferred pneumatic systems include the HSS™ systems by Plas-Pak Industries, Norwich Conn. Both manual and pneumatic dispensing guns are available, for example from V.O. Baker Co., Mentor Ohio. Hydraulic dispensing systems may suitably operate at pressures on the order of 800 psi. The roller attachment 7 preferably includes a perforated or bleed through roller core and/or cover. Non-limiting examples of suitable perforated roller covers are available, for example, from Hennes-Johnson Equipment Co., Prague Minn.; and Wagner Spray Tech Corporation, Minneapolis Minn. For the roller coater embodiment, any roller 7 suitable for the paint may be used, including perforated roller cores and covers. One preferred embodiment of the present invention provides a system that packages marine, military, and industrial multi-component reactive liquid paints in cartridges for dispensing and direct rolling or spraying paints by manual, pneumatic, or hydraulic methods. Another method of the present invention provides a method for applying a high-solids, low VOC marine or military paint, to a surface using a multi-component cartridge. The current system is particularly suitable for use in dispensing and applying multi-component coating systems, marine and military paints. Just dispensing the components in the correct proportions is insufficient. When dispensed, the components must be mixed to activate the curing process. As stated previously, however, manual mixing has certain drawbacks. The present invention provides a means of storing, dispensing, mixing, and applying reactive multi-component paints at or near point of use, conveniently, safely and with significantly reduced waste and improved coating performance. In this manner any amount of paint can be prepared for use, from very small amounts to large amounts. This avoids waste and provides a system for providing just the right amount of prepared paint for the time available for application. The present invention desirably reduces the problems encountered with multi-component, reactive and high-solids paints. These include the problems of hot potting, inaccurate proportioning, mixing, and human error. The present invention increases the ease of coating application for painters to apply coatings. In addition, because the coating reactants remain sealed until mixed and applied, it is safer for the painters as it reduces their exposure to often toxic reactants, such as curing catalysts, isocyanates, and the like. In addition, the present invention results in a more manageable process on an industrial scale, it drastically reduces paint can change out time, waste due to expired pot life and spillage, and clean-up solvent. The present invention is particularly suitable for marine and military paint multi-component paints. In accordance with the present invention, preloaded disposable paint cartridges with disposable static mixers keep the base and hardener separate from one another as long as possible and allow dispensing of paint on demand. A preloaded disposable paint cartridge with disposable static mixer is used to mix the multi-component systems as close to the cartridge as possible. The use of preloaded disposable paint cartridges with disposable static mixers eliminates pot life problems and viscosity problems that result in waste and application difficulties. Preloaded disposable military and marine paint cartridges with disposable static mixers reduce the problems encountered with viscosity and pot life by keeping the two components separate as long as possible. Keeping the reactive components of multi-component coatings separate eliminates the risk of the coatings curing before use. Components are mixed at the work site when needed. This not only reduces the amount mixed and waste generated, it improves product integrity by maintaining exact ratios, thereby allowing the end user to achieve maximum service life expectancy. Military and marine coatings are much more sensitive than traditional solvent based epoxies and coatings. In the present application, marine and military paints are especially formulated to be used in a saltwater marine environment and/or are specified by the U.S. military, such as the U.S Army, Navy, Marine Corps, Air Force, Military Sealift Command, and/or Coast Guard. These coatings must be mixed properly and thoroughly according to manufacturers specifications in order to cure. High solids coatings, and particularly those for marine and military applications, have specific mix ratios with very tight tolerances, generally plus or minus 3%. There are many different factors that affect whether a coating will be on or off ratio. In accordance with the present invention, preloaded disposable military and marine paint cartridges with disposable static mixers assures the mix ratios are maintained when dispensing. In accordance with one embodiment of the present invention, these dispensing systems are combined with a paint roller or brushing apparatus and method. In accordance with another embodiment of the present invention, a multi-component cartridge preloaded with one or more reactive components of a high solids, low VOC marine and military paint. The entire contents of each of the references, patents, and patent applications cited herein is hereby incorporated by reference, the same as if set forth at length. Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically recited herein.

A device for applying a mixed component includes first and second component reservoirs, a static mixing nozzle configured to mix first and second components into the mixed component, a component passage disposed between the component reservoirs and the first end of the static mixing nozzle, the component passage disposed to enable the first and second components to flow from the reservoirs to the static mixing nozzle, a spray tip including an air inlet disposed at least partially between the first end of the spray tip and the second end of the spray tip, the first end of the spray tip being disposed adjacent the second end of the static mixing nozzle, a component applicator configured to use air to apply the mixed component through the second end of the spray tip, and a trigger mechanism disposed on the component applicator, and configured to enable application of the mixed component.

CROSS-REFERENCE TO RELATED APPLICATION [0001] This application claims the benefit of Korean Patent Application No. 10-2008-0127937, filed on Dec. 16, 2008, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. BACKGROUND [0002] 1. Field of the Invention [0003] The present invention relates to a method and an apparatus of transmitting packet filtering information. [0004] 2. Description of the Related Art [0005] A U.S. standard off-cable scheme transmits additional broadcasting information providing various service information, such as system information (SI), electronic program guide (EPG) information, conditional access information, an emergency alarm, video on demand (VOD), a game, and the like, together with a broadcasting program via an out-of-band in a bidirectional digital environment. [0006] Also, when a digital cable broadcasting receptor intends to receive the broadcasting additional information transmitted via the out-of-band, a method that selectively separates general data and broadcasting additional information data, the general data being transmitted to a Data Over Service Interface Specification (DOCSIS) channel through a Cable Modem Termination System (CMTS) and the broadcasting additional information data being processed by a cable broadcasting receptor, is standardized in a DOCSIS set-top Gateway (DSG). [0007] A set-top controller is a device for transmitting the broadcasting additional data over a cable network, and examples of the set-top controller include an SI server, a conditional access system server, and the like. Data of the set-top controller is transmitted to a CMTS of a cable headend in a form of an Internet protocol (IP) multicast over an IP network, and a DSG module contained in the CMTS transmits, to each subscriber connected to the cable network, the data received from the set-top controller in a form of a multicast. In this instance, the DSG module contained in the CMTS changes a destination media access control (MAC) address into a DSG tunnel address, the destination MAC address being included in each packet transmitted from the set-top controller to the subscriber. The DSG tunnel address is important information utilized for classifying the broadcasting additional data, such as SI data, conditional access data, and the like, transmitted on a DOCSIS channel. Also, the cable broadcasting receptor, containing a cable modem having a DSG function, determines a type of the inputted broadcasting additional information by utilizing a corresponding address value as data filtering information, and the cable broadcasting receptor also determines a process method for the inputted broadcasting additional information. [0008] The DSG standard is divided into one of a DSG basic mode and a DSG advanced mode depending on a DSG tunnel address setting and operating method. [0009] The DSG basic mode stores information with respect to the DSG tunnel address in a cable card that a cable broadcasting operator distributes to a subscriber, to enable the cable broadcasting receptor containing the cable modem to selectively receive desired broadcasting additional data. As the cable card is operating after being inserted to the cable broadcasting receptor, the corresponding information is transmitted to the cable modem, and the cable modem constructs a DSG tunnel filter based on the corresponding information, thereby receiving the desired broadcasting additional data. [0010] Conversely, the DSG advanced mode transmits the DSG tunnel address and related information to the cable modem from the CMTS through a downstream channel descriptor (DCD) that is a specially defined as a DOCSIS MAC management message, and the cable modem that receives the DCD message constructs a DSG tunnel filter based on the information included in the DCD message, thereby receiving desired broadcasting additional data. [0011] Differences between the DSG basic mode and the DSG advanced mode are as follows. [0012] In the DSG basic mode, when the DSG tunnel address is changed due to a change of a system, such as a server providing broadcasting additional data, and the like, it is difficult to change DSG tunnel address information of a cable card distributed to the subscriber in advance because the DSG tunnel address designated in the CMTS of the broadcasting headend is distributed in a form stored in the CMTS. Also, a current open-cable standard limits a number of the DSG tunnel addresses to be defined by the DSG basic mode as eight, thereby having a difficulty in enlarging the system. [0013] Conversely, in the DSG advanced mode, information related to DSG tunnel construction is transmitted to the cable modem contained in the cable broadcasting receptor through the DCD that is one of DOCSIS MAC management messages, and thus, it is convenient to change and enlarge the DSG channel construction when the system in the broadcasting headend is changed. [0014] However, to use the DSG advanced mode, all devices operated in the current DSG basic mode are required to be replaced with devices operated in the DSG advanced mode. SUMMARY [0015] An aspect of the present invention provides a method of transmitting Data Over Service Interface Specification (DOCSIS) set-top Gateway (DSG) channel construction information to a designated channel without replacing devices operated in a DSG basic mode, such as a cable modem termination system (CMTS), a cable modem, and the like, with devices in a DSG advanced mode, thereby dynamically constructing a DSG channel even in a device in the DSG basic mode. [0016] According to example embodiments, there may be provided a method of controlling a DSG channel information server, including generating a DSG channel information message including a destination media access control (MAC) address used for filtering packets for each data type, the destination MAC address being included in each of the packets, and transmitting the DSG channel information message to a cable broadcasting receptor using a predetermined multicast address. [0017] In this instance, the transmitting of the DSG channel information message may include providing the DSG channel information message to a CMTS, and transmitting, by a DSG module included in the CMTS, the DSG channel information message in a form of a multicast to the cable broadcasting receptor. [0018] Also, the DSG channel information message may include information used for filtering the packets for each data type. [0019] Also, the DSG channel information message may include a DSG channel information message header including identification information of the DSG channel information message, and DSG channel information data including DSG channel information. [0020] Also, the DSG channel information message header may include a message identification (ID) to identify the DSG channel information message, a change counter being capable of determining whether the DSG channel information message is changed by changing a value according to a change of the DSG channel information, and a number of fragments and a fragment number to provide connection information of the DSG channel information message header. [0021] Also, the DSG channel information data may include a number of DSG tunnels being information related to the number of the DSG tunnels constructed from a broadcasting headend, and DSG tunnel information including filtering information of the DSG tunnels. [0022] Also, the DSG tunnel information may include a DSG tunnel MAC address to be used for identifying and filtering broadcasting additional information data, a DSG tunnel Internet protocol (IP) address to provide a source IP address of a server that transmits the DSG channel information data, and a DSG data type to represent a data type of the DSG channel information data. [0023] According to example embodiments, there may be provided a method of controlling a CMTS, the method including receiving a DSG channel information message including a destination MAC address used for filtering packets for each data type, the destination MAC address being included in each of the packets, and transmitting, by a DSG module, the DSG channel information message in a form of a multicast, to a cable broadcasting receptor. [0024] In this instance, the transmitting of the DSG channel information message may include changing, by the DSG module, the destination MAC address into a DSG tunnel address, and transmitting the DSG channel information message including the destination MAC address in the form of the multicast, to a cable broadcasting receptor. [0025] Also, the transmitting of the DSG channel information message may include selecting, by the DSG module, a predetermined address from a multicast address area, and transmitting the DSG channel information message in the form of the multicast, to the cable broadcasting receptor. [0026] According to example embodiments, there may be provided a method of controlling a cable broadcasting receptor, the method including receiving a DSG channel information message transmitted in a form of a multicast via a DSG tunnel corresponding to a predetermined DSG tunnel address, constructing a DSG channel filter that performs filtering of received data using the DSG channel information message, and receiving data filtered by the DSG channel filter. [0027] In this instance, the filtered data may include broadcasting additional information including at least one of system information (SI), conditional access information, and electronic program guide (EPG) information. [0028] According to example embodiments, there may be provided a DSG channel information server, including a DSG channel information message generating unit to generate a DSG channel information message including a destination MAC address used for filtering packets for each data type, the destination MAC being included in each of the packets, and a transmitting unit to transmit the DSG channel information message to a cable broadcasting receptor using a predetermined multicast address. [0029] In this instance, the transmitting unit may provide the DSG channel information message to a CMTS and may enable a DSG module included in the CMTS to transmit the DSG channel information message in a form of a multicast to a cable broadcasting receptor. [0030] According to example embodiments, there may be provided a CMTS, including a receiving unit to receive a DSG channel information message including a destination MAC address used for filtering packets for each data type, the destination MAC address being included in each of the packets, and a DSG module to transmit the DSG channel information message in a form of a multicast to a cable broadcasting receptor. [0031] In this instance, the DSG module may change the destination MAC address into a DSG tunnel address, and may transmit the DSG channel information message including the destination address in the form of the multicast to the cable broadcasting receptor. [0032] Also, the DSG module may select a predetermined address from a multicast address area, and may transmit the DSG channel information message in the form of the multicast to the cable broadcasting receptor. [0033] According to example embodiments, there may be provided a cable broadcasting receptor, including a cable modem to receive a DSG channel information message transmitted in a form of multicast through a DSG tunnel corresponding to a predetermined DSG tunnel address, and a DSG channel filter constructing unit to construct a DSG channel filter to perform filtering of received data using the DSG channel information message. Here, the cable modem receives data filtered through the DSG channel filter. [0034] In this instance, the filtered data may include broadcasting additional information including at least one of system information (SI), conditional access information, and EPG information. [0035] Additional aspects, features, and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS [0036] These and/or other aspects, features, and advantages of the invention will become apparent and more readily appreciated from the following description of exemplary embodiments, taken in conjunction with the accompanying drawings of which: [0037] FIG. 1 is a configuration diagram illustrating a digital cable broadcasting system according to an embodiment of the present invention; [0038] FIG. 2 is a configuration diagram illustrating a Data Over Service Interface Specification (DOCSIS) set-top Gateway (DSG) channel information sever according to an embodiment of the present invention; [0039] FIG. 3 is a configuration diagram illustrating a cable modem termination system (CMTS) according to an embodiment of the present invention; [0040] FIG. 4 is a configuration diagram illustrating a cable broadcasting receptor according to an embodiment of the present invention; [0041] FIG. 5 is a diagram illustrating a configuration of a DSG channel information message that is provided by a DSG channel information server, according to an embodiment of the present invention; [0042] FIG. 6 is a diagram illustrating a method of changing a destination media access control (MAC) address of a DSG channel information server packet in a CMTS, according to an embodiment of the present invention; [0043] FIG. 7 is a flowchart illustrating a method of controlling a DSG channel information server according to an embodiment of the present invention; [0044] FIG. 8 is a flowchart illustrating a method of controlling a CMTS according to an embodiment of the present invention; and [0045] FIG. 9 is a flowchart illustrating a method of controlling a cable broadcasting receptor according to an embodiment of the present invention. DETAILED DESCRIPTION [0046] Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. Exemplary embodiments are described below to explain the present invention by referring to the figures. [0047] FIG. 1 is a configuration diagram illustrating a digital cable broadcasting system according to an embodiment of the present invention. The digital cable broadcasting system according will be described in detail with reference to FIG. 1 . [0048] The digital cable broadcasting system according to an embodiment of the present invention may include a DSG channel information server 110 providing Data Over Service Interface Specification (DOCSIS) set-top Gateway (DSG) channel information, a set-top controller 111 , a cable modem termination system (CMTS) 130 , and a digital cable broadcasting receptor 140 . [0049] In the cable broadcasting system, the DSG channel information server 110 may generate a DSG channel information message used for dynamically transmitting the DSG channel information to a broadcasting receptor from a broadcasting headend, and may output the DSG channel information message to a cable broadcasting receptor 140 using a multicast address designated in the CMTS 130 . [0050] The set-top controller 111 may provide broadcasting additional information, such as system information (SI), conditional access information, electronic program guide (EPG) information, and the like. A DSG channel information message generated from the set-top controller 111 is transmitted to the CMTS 130 of a cable headend in a form of an Internet protocol (IP) multicast over an IP network 120 . [0051] The CMTS 130 may receive the DSG channel information message from the DSG channel information server 110 , and DSG module 131 included in the CMTS 130 changes a destination MAC address of a packet including the received DSG channel information message into a DSG channel address designated as an invariable value. [0052] Also, the CMTS 130 may output the DSG channel address, which is changed into the invariable value, to the cable broadcasting receptor 140 over a cable network. [0053] In this instance, an address mutually agreed upon between the broadcasting headend and the cable broadcasting receptor is freely selected from a multicast address area as the DSG tunnel address used for transmitting the DSG channel information. [0054] The cable broadcasting receptor 140 containing a cable modem may receive the DSG channel construction information message using the designated DSG tunnel address, and may construct a DSG channel filter based on the received DSG channel construction information message. [0055] When construction of the DSG channel filter is completed, the broadcasting additional information, such as SI information, conditional access information, and the like, based on the corresponding address information is received. [0056] Therefore, exemplary embodiments of the present invention may transmit DSG channel construction information to a designated channel without replacing the devices operated in the DSG basic mode, such as a CMTS, a cable modem, and the like, with devices of DSG advanced mode, and thus the DSG channel may be dynamically constructed even in a device in a DSG basic mode. [0057] FIG. 2 is a configuration diagram illustrating a DSG channel information sever according to an embodiment of the present invention. [0058] As illustrated in FIG. 2 , the DSG channel information server may include a DSG channel information message generating unit 210 and a transmitting unit 220 . [0059] The DSG channel information message generating unit 210 generates a DSG channel information message. In this instance, the DSG channel information message includes a destination MAC address used for filtering packets for each data type, the destination MAC address being included in each of the packets. [0060] The transmitting unit 220 transmits the generated DSG channel information message to a cable broadcasting receptor using a predetermined multicast address. [0061] Particularly, the transmitter 220 may provide the DSG channel information message to a CMTS, and the CMTS may transmit the DSG channel information message in a form of a multicast to the cable broadcasting receptor using a DSG module included in the CMTS. [0062] FIG. 3 is a configuration diagram illustrating a CMTS according to an embodiment of the present invention. [0063] As illustrated in FIG. 3 the CMTS may include a receiving unit 310 and a DSG module 320 . [0064] The receiving unit 310 receives a DSG channel information message including a destination MAC address of a packet. [0065] The DSG module 320 transmits the DSG channel information message in a form of a multicast to a cable broadcasting receptor. [0066] In this instance, the DSG module 320 changes the destination MAC address of the packet into a DSG tunnel address, and transmits the DSG channel information message including the destination MAC address of the packet in the form of the multicast to the cable broadcasting receptor. [0067] Also, the DSG module 320 selects a predetermined address from a multicast address area and transmits the DSG channel information message in the form of the multicast to the cable broadcasting receptor. [0068] FIG. 4 is a configuration diagram illustrating a cable broadcasting receptor according to an embodiment of the present invention. [0069] As illustrated in FIG. 4 , the cable broadcasting receptor may include a cable modem 410 , and a DSG channel filter constructing unit 420 . [0070] The cable modem 410 receives a DSG channel information message transmitted in a form of a multicast via a DSG tunnel corresponding to a selected DSG tunnel address. [0071] The DSG channel filter constructing unit 420 constructs a DSG channel filter that performs filtering of received data using the DSG channel information message. [0072] The cable modem 410 receives data filtered through the DSG channel filter. [0073] In this instance, the filtered data may include at least one of SI information, conditional access information, and EPG information. [0074] FIG. 5 is a diagram illustrating a configuration of a DSG channel information message that is provided by a DSG channel information server, according to an embodiment of the present invention. [0075] The DSG channel information message includes a DSG channel information message header 501 including message identification information and the like, and a DSG channel information data 502 including DSG channel information. [0076] The DSG channel information message header 501 includes a message identification (ID) 503 for identifying a message, a change counter 504 increasing a value by one when the DSG channel information is changed, thereby determining whether the message is changed, and a number of fragments 505 and a fragment number 506 providing connection information of a message. [0077] The DSG channel information data 502 including the DSG channel construction information includes a number of DSG tunnels 507 indicating a number of DSG tunnels constructed from the broadcasting headend, and a plurality of DSG tunnel information 508 , 509 , and 510 including filtering information of the DSG tunnels. [0078] Each of the DSG tunnel information 508 , 509 , and 510 includes a DSG tunnel MAC address 511 for identifying broadcasting additional information data and for filtering, a DSG tunnel IP address 512 providing a source IP address of a server that transmits corresponding data, and a DSG data type 513 indicating data type of received data. [0079] The cable modem of the cable broadcasting receptor that receives the message constituted as described above, may construct a DSG channel filter according to received information and may transmit filtered data to each process module of the broadcasting receptor according to a use. [0080] FIG. 6 is a diagram illustrating a method of changing a destination MAC address of a DSG channel information server packet in a CMTS, according to an embodiment of the present invention. [0081] As illustrated in FIG. 6 , a DSG channel information message transmitted to the CMTS 620 from a DSG channel information server 610 is transmitted in a form of an IP multicast to CMTS 620 . [0082] A DSG module 621 included in the CMTS 620 receives packets having a designated IP multicast address, and changes a destination MAC address 640 of the corresponding packets into a predetermine DSG tunnel address 650 . [0083] Information where the DSG tunnel address 650 and the multicast IP address used for data transmission are mapped is freely changed in a multicast address area according to a set value. In this instance, an initial DSG tunnel address used for transmitting the DSG channel information may be a mutually agreed upon value between a broadcasting headend and a broadcasting receptor, in advance. [0084] FIG. 7 is a flowchart illustrating a method of controlling a DSG channel information server according to an embodiment of the present invention. [0085] As illustrated in FIG. 7 , a DSG packet information message generating unit generates a DSG channel information message including a destination MAC address used for filtering packets for each data type in operation S 710 , the destination MAC address being included in each of the packets. [0086] In this instance, the DSG channel information message includes information used for filtering the packets for each type. [0087] Subsequently, the transmitting unit transmits the DSG channel information message to a cable broadcasting receptor using a predetermined multicast address in operation S 720 . [0088] That is, the DSG channel information message transmitted by the transmitting unit may be transmitted to a CMTS, and also may be transmitted to the cable broadcasting receptor by a DSG module included in the CMTS. [0089] FIG. 8 is a flowchart illustrating a method of controlling a CMTS according to an embodiment of the present invention. [0090] As illustrated in FIG. 8 , a receptor receives a DSG channel information message including a destination MAC address used for filtering packets for each data type in operation S 810 , the destination MAC address being included in each of the packets. [0091] Subsequently, a DSG module transmits the DSG channel information message in a form of a multicast to a cable broadcasting receptor in operation S 820 . [0092] In this instance, the DSG module changes the destination MAC address into a DSG tunnel address, and transmits the DSG channel information message including the destination MAC address in the form of the multicast to the cable broadcasting receptor. [0093] Also, the DSG module selects a predetermined address from a multicast address area and transmits the DSG channel information message in the form of the multicast to the cable broadcasting receptor. [0094] FIG. 9 is a flowchart illustrating a method of controlling a cable broadcasting receptor according to an embodiment of the present invention. [0095] As illustrated in FIG. 9 , a cable modem receives a DSG channel information message transmitted in a form of a multicast via a DSG tunnel corresponding to a predetermined DSG tunnel address in operation S 910 . [0096] Subsequently, a DSG channel filter constructing unit constructs a DSG channel filter that performs filtering of received data using the DSG channel information message in operation S 920 . [0097] Data filtered through the constructed DSG channel filter is received in operation S 930 , and the data is transmitted to a corresponding process module according to a data type. [0098] In this instance, the filtered data may include at least one of SI information, conditional access information, and EPG information. [0099] Accordingly, it is possible to transmit DSG channel construction information to a designated channel without replacing the devices operated in the DSG basic mode, such as a CMTS, a cable modem, and the like, with devices of DSG advanced mode and thus, the DSG channel is dynamically constructed. [0100] According to an exemplary embodiments of the present invention, there may be provided a method of transmitting DSG channel construction information to a designated channel without replacing the devices operated in the DSG basic mode, such as a CMTS, a cable modem, and the like, with devices of DSG advanced mode, thereby dynamically constructing the DSG channel even in a device in a DSG basic mode. [0101] Accordingly, cost expended for replacing the existing device, to utilize all advantages in the DSG advanced mode, may be reduced, and a DSG basic mode-based cable modem-containing cable broadcasting receptor may have the advantages of the device in DSG advanced mode by merely changing software. [0102] Although a few exemplary embodiments of the present invention have been shown and described, the present invention is not limited to the described exemplary embodiments. Instead, it would be appreciated by those skilled in the art that changes may be made to these exemplary embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Disclosed are a method and an apparatus of transmitting packet filtering information. A DSG channel information management server included in a digital cable broadcasting transmission headend combines a packet address and information related to the packet address and generates the combined information to be a single file, the packet address being used for filtering packets received by a cable modem contained in a cable broadcasting receptor, for each data type. The generated file is transmitted from a CMTS to the cable modem through a packet having a designated address mutually agreed upon between the headend and the cable modem, the cable modem obtains information for selectively filtering the received packets, from the received file, and constructs a filter. Data selectively filtered through each constructed filter is transmitted to a corresponding process module included in the cable broadcasting receptor that processes broadcasting program information, conditional access information, and the like.

BACKGROUND OF THE INVENTION U.S. Pat. No. 4,001,742 entitled "Circuit Breaker Having Improved Operating Mechanism" describes a circuit breaker capable of interrupting several thousand amperes of circuit current at several hundred volts potential. As described therein, the operating mechanism controls the powerful operating springs that open and close the circuit breaker contacts. Once the operating mechanism has responded to separate the contacts, the operating springs must be recharged to supply sufficient motive force to the movable contact arms that carry the contacts. U.S. patent application Ser. No. 08/218,287 filed on 28 Mar. 1994 entitled "Handle Operator Assembly for High Ampere-rated Circuit Breaker" describes an assembly for manually charging the circuit breaker contact closing springs. U.S. patent application Ser. No. 08/214,522 filed on 3 Mar. 1994 entitled "Latching Arrangement for High Ampere-rated Circuit Breaker" describes the latching arrangement used to retain the powerful operating mechanism springs from driving the circuit breaker contacts to the closed position. U.S. patent application Ser. No. 08/265,877 entitled filed on 27 Jun. 1994 "Handle Interlock Arrangement for High Ampere-Rated Circuit Breakers" describes restraining the circuit breaker operating handle after the circuit breaker contact closing springs have become fully charged. U.S. patent application Ser. No. 08/304,331 entitled "Positive Charge Indicator Arrangement for High Ampere-Rated Circuit Breaker" describes interlocking the circuit breaker charging springs indicator flag by means of a logic plate and logic lever to prevent the charge indicating flag from signaling until and unless the closing springs are fully charged. U.S. patent application Ser. No. 08/266,409 filed on 27 Jun. 1994 entitled "Sequential Close Interlock Arrangement for a High-Rated Circuit Breaker" describes the interaction between a closing link and the circuit breaker contact closing springs button to prevent operation of the closing button unless the closing springs are fully charged. The purpose of this invention is to interlock the circuit breaker contact closing springs per se to prevent release of the closing springs when the contact springs are only partially charged. SUMMARY OF THE INVENTION In a high ampere-rated circuit breaker including contact closing springs for closing the circuit breaker contacts, the externally-accessible contact springs closing button interacts with a logic plate, a logic lever, an interlock link and a closing link to prevent the closing button from releasing the closing springs until and unless the closing springs have become fully charged. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top perspective view of a high ampere-rated circuit breaker with a portion of the circuit breaker cover removed to depict the contact closing springs interlock assembly according to the invention; FIG. 2 is an enlarged top perspective view of the contact closing springs interlock assembly of FIG. 1 with the components in isometric projection; FIG. 3 is an enlarged plan side view of the contact closing springs interlock assembly of FIG. 1 with the circuit breaker closing springs in a discharged condition; and FIG. 4 is an enlarged plan side view of the contact closing springs interlock assembly of FIG. 1 with the circuit breaker closing springs in a fully-charged condition. DESCRIPTION OF THE PREFERRED EMBODIMENT The high ampere-rated circuit breaker 10 shown in FIG. 1 is capable of transferring several thousand amperes quiescent circuit current at several hundred volts potential. The circuit breaker consists of an electrically insulated base 11 to which an intermediate cover 11A of similar insulative material is attached prior to attaching the top cover 12 also consisting of an electrically-insulative material. Electrical connection with the interior current-carrying components is made by load terminal straps extending from one side of the base and line terminal straps (not shown) extending from the opposite side thereof. The interior components are controlled by an electronic trip unit 13 contained within a recess 13A on the top surface of the top cover 12 The trip unit is similar to that described within U.S. Pat. No. 4,658,323 and interacts further with an accessory 14 within an accessory recess 14A to provide a range of protection and control functions such as described, for example within U.S. Pat. No. 4,801,907. The operating mechanism as described within U.S. patent application Ser. No. 08/203,062 filed on 28 Feb. 1994 entitled "Rating Module Unit for High Ampere Rated Circuit Breakers includes a closing shaft 15 which provides the forces required to charge the powerful operating mechanism contact closing springs 16. The operating handle 17 arranged within the handle recess 17A allows manual operation of the circuit breaker operating mechanism as well as providing manual means for charging the contact closing springs. The handle is attached to the operating mechanism sideframe 28 by means of the handle pivot pin 41 and is connected with the handle drive gear 18 by a pair of handle drive links 22. The handle drive gear interacts with a locking pawl 19 to restrain the handle drive gear from reverse rotation during the contact operating spring charging process as described in the aforementioned U.S. patent application Ser. No. 08/214,522. The primary and intermediate latches 20, 21 restrain the operating mechanism from responding when the closing springs have become fully charged. To turn on the circuit breaker by moving the circuit breaker contacts within the base to the closed condition, the closing button 24 is depressed to release the closing springs. The CLOSED indicating flag which is associated with the closing button is visible under the closed indicating flag access slot 24A. The circuit breaker contacts are turned off by means of the opening button 23 and the OPEN indicating flag associated with the opening button is visible under the open indicating flag access slot 23A. In accordance with the invention, a closing springs interlock assembly 27 in the form of a logic plate 25 and interlock link 26 insures that the closing button 24 cannot release the closing springs unless, and until, the closing springs are fully charged. The interlock assembly 27 is shown apart from the circuit breaker in FIG. 2 to depict the location of the interlock link 26, logic plate 25 and handle drive gear 18 relative to the handle pivot 41, interlock link pivot 42, drive shaft 29 closing shaft 15 and locking pawl pivot 30 on the side frame 28. The components within the interlock assembly are similar to those described within the aforementioned U.S. patent application Ser. No. 08/304,331. The locking pawl 19 is arranged on the pivot pin 30 by means of the thru-hole 31 and the pin 34 on the locking pawl extends through the slot 35 formed on the logic lever 33. The same pin 30 extends through the thru-hole 32 on the logic lever so that the pivot pin 30 is common to both the locking pawl and the logic lever. The handle drive gear 18 and the logic plate 25 are assembled on the closing shaft 15 by means of the openings 37, 38 respectively and the pin 39 extending from the handle drive gear 18 is captured within the slot 40 formed in the logic plate 25 to allow lost motion between the drive gear and the logic plate until the pin 39 contacts the edge of the slot 40 and causes the logic plate to move in unison with the drive gear as described within the aforementioned U.S. patent application Ser. No. 08/304,331. As further described therein, the tab 36 on the logic lever 33 interacts with the outer perimeter of the logic plate 25 to set the position of the indicating flag relative to the charged and uncharged conditions of the contact closing springs 16 (FIG. 1). The interlock link 26 is mounted on the sideframe 28 by means of the pivot pin 42 and interacts with the logic plate 25 by means of the offset tab 46. The interlock link interacts with the cam 29A on the closing shaft 29 by means of the offset tab 44 and with the operating handle by means of the slot 50 (FIG. 3) at one end of the operating handle 17 (FIG. 1). The interlock link further interacts with the closing link 51 by means of a slot (not shown) within the closing link as best seen by now referring to the closing spring interlock assemblies 27 depicted in FIGS. 3 and 4. The interlock link 26 interacts with the closing link 51 to prevent the closing link from contacting the latch bracket 48 and thereby release the primary and secondary latches 21, 20 as described within the aforementioned U.S. patent application Ser. No. 08/266,405 when the closing button 24 is depressed and the contact charging springs are less then fully charged as with the interlock assembly 27 shown in FIG. 3. The operating handle 17 is positioned on the handle pivot 41 with the handle interlock slot 50 away from the handle interlock tab 49 at one end of the interlock link 26. The reset-lockout tab 46 on the interlock link 26 is positioned on the detent 25B on the perimeter of the logic plate 25 and the cam 29A on the drive shaft 29 is away from the positioning tab 44 on the interlock link since the circuit breaker contacts are in the open condition. In this position, the pin 39 on the handle drive gear 18 is away from the edge of the slot 40 within the logic plate 25 which allows the drive shaft 29 to rotate without rotating the logic plate and displacing the locking lever tab 36 on the logic lever 33 away from the cam surface 25A until the contact charging springs have become fully charged as described within the aforementioned U.S. patent application Ser. No. 08/304,331. When the contact closing springs have become fully charged, as shown within the interlock assembly 27 in FIG. 4, the handle interlock tab 49 on the end of the interlock link 26 sits within the handle interlock slot 50 at the end of the operating handle 17 and the positioning tab 44 on the bottom of the interlock link is away from the cam 29A on the drive shaft 29. When the circuit breaker contact are open, the pin 39 on the handle drive gear 18 has contacted the edge of the slot 40 on the logic plate 25 to rotate the logic plate and allow the locking lever tab 36 on the logic lever 33 to drop away from the cam surface 25A and to allow the reset lockout tab 46 to drop away from the detent surface 25B on the logic plate. The closing link 51, as shown in phantom, is now in line with the latch bracket 48 which allows the closing button 24 also shown in phantom at the opposite end of the closing link to drive the end of the closing link against the latch bracket to thereby release the primary and secondary latches 20, 21 and allow the closing shaft 15 to rotate and release the contact closing springs back to the discharged position shown in FIG. 4. At the same time, the camming surface 18A on the handle drive gear 18 becomes positioned under the reset-locktab tab 46 to lift the reset-locktab back onto the detent surface 25 as indicated. A contact closing spring arrangement 27 has herein been described wherein an interlock link 26 interacts with the circuit breaker operating handle 17, drive shaft 29, logic plate 25 and closing link 51 to sequentially allow the contact closing button to release the contact closing springs as soon as the contact closing springs have become fully charged.

This invention relates to a high ampere-rated circuit breaker which meets the electrical code requirements of the world market. The charging of the powerful closing springs controlling the circuit breaker contacts is made manually by means of a ratchet and pawl assembly. A logic plate interacts with a logic lever, an interlock link and a closing link to prevent the circuit breaker closing button from operating until and unless the closing springs have become fully-charged.

[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 10/038,219, filed Jan. 3, 2002 which is incorporated in its entirety. FIELD OF THE INVENTION [0002] The present invention relates to a tufting machine with replaceable self-aligning gauge modules and is more particularly concerned with gauge modules with individually replaceable gauge elements which can be readily installed and removed. BACKGROUND OF THE INVENTION [0003] Tufting machines are built with precision so that the needles and loopers of the machine are accurately spaced from each other along the needle bar or looper bars. The loopers and needles must be spaced from each other so that the looper bills pass closely adjacent to the needles to engage and hold loops of yarns carried by the needles. When assembling a tufting apparatus, errors in positioning these gauge elements may accumulate as the work progresses. The present invention seeks to establish consistency with these parts across the width of the apparatus, to provide a tufting environment, suitable even for narrow gauge configurations. The present invention also addresses the problem of replacing individual gauge elements that become broken or damaged during tufting. In most modular designs, a broken gauge element requires discarding the entire modular block containing a set of about one to two dozen gauge elements. The present invention allows for quick and efficient replacement of individually damaged gauge elements. [0004] The idea of replacing individual components of assemblies in tufting machines is not new. In the past, knife holder assemblies have been devised that allow for the replacement of individual knives. The knives were arranged in pre-assembled or modular fashion in a knife holder, each knife holder having a guide mechanism which enabled groups of knives, each group in a separate holder, to be positioned on a carrying member of a tufting machine and maintained in appropriate alignment. U.S. Pat. Nos. 4,608,934; 4,669,171; 4,691,646; and 4,693,191 illustrate such prior art knife holder assemblies in which parallel knives are disposed. These prior art knife holder assemblies are then disposed in transverse bars provided with guides for positioning the holders in appropriate positions on a tufting machine. [0005] Needles have previously been individually secured in modular gauge blocks as shown in U.S. Pat. No. 4,170,949, and hooks and knives have also been individually secured in gauge parts mounting blocks as shown in U.S. Pat. No. 4,491,078. These designs have used individual clamping screws to hold each gauge element in place. These blocks were not mated with slots on the carrying members and were heavily machined. In addition, the clamping screws used in these gauge blocks have typically been flat ended and have relied upon the flat tip pushing directly against the gauge element to securely position those gauge elements. When the blocks are machined from relatively soft metals such as aluminum, there has been a tendency for the threads of the block to become worn and allow too much play for all of the screws to securely hold their corresponding gauge elements. [0006] More recently attempts have been made to incorporate needles and loopers into replaceable modular blocks. U.S. Pat. Nos. RE 37,108, 5,896,821, 5,295,450 illustrate such modular gauge assemblies in which the gauge elements are permanently embedded into the modular block. The block is attached to the guide bar with a single screw allowing for removal and replacement of the block. One shortcoming of these modular blocks is that when a single gauge element breaks the entire modular block must be discarded. SUMMARY OF THE INVENTION [0007] The present invention includes a modular gauge assembly that attaches to a gauge bar. The gauge bar has a plurality of positioning recesses that allows a detent on an individual modular block to be accurately positioned along the gauge bar. Each modular block typically includes a front surface, a pair of side surfaces opposed to each other, a rear surface opposite to the front surface, and a bottom surface. [0008] A tongue, which may or may not be a part of the cast block extends from a rear or bottom surface of the modular block. The tongue includes a threaded hole which along with a securing screw serves to mount the block to a gauge bar. The threaded hole aligns with the gauge bar receiving hole when the tongue of the modular block is positioned properly with a recess on the gauge bar. When sufficiently tightened, the securing screw holds the modular block to the gauge bar. [0009] At least the front surface of the block contains a plurality of spaced parallel slots so that gauge elements may be positioned in the slots with proper spacing. The proximal ends of the gauge elements may have apertures or channels recessed therein. In one embodiment of the present invention the proximal ends of the gauge elements are inserted into the block and secured there by a lateral pin that enters the block on one of the opposing side surfaces and passes through apertures on the proximal ends of the gauge elements. An alternative embodiment biases a lateral pin resting in a channel on the proximal ends of the gauge elements by tightening a securing bolt that is in communication with the lateral pin through an opening on the block. The preferred securing bolts have conical ends to exert a wedging or camming force against the lateral pin. In either case the gauge elements are secured by a lateral pin engaging the gauge elements. Individual gauge elements can be replaced by demounting the affected block, removing the lateral pin and removing a selected gauge element. After the selected gauge element is removed a new gauge element may be re-inserted into the proper vertical slot and secured by the lateral pin and securing bolt. [0010] A plurality of modular blocks are arranged along the surface of the gauge bar and are vertically positioned on the gauge bar by a horizontal surface of the gauge bar or of a guide bar that passes through a guide bar channel on the gauge bar. The width of each block is substantially equal to the distance between the positioning recesses of the gauge bar so that the edges of the blocks abut one another and the blocks are laterally positioned. [0011] In an alternative embodiment of the present invention each modular gauge assembly attaches to a gauge bar having a plurality of positioning recesses that allows the detent on the individual modular block to laterally position the block on the gauge bar. Each modular block typically includes a front surface, a pair of side surfaces opposed to each other, a rear surface opposite to the front surface, and opposing bottom and top surfaces. The rear surface contains a rectangular tab or detent that includes a threaded hole to receive a securing screw. The threaded hole aligns with the gauge bar receiving hole when the modular block is positioned properly on the gauge bar. When tightened, the securing screw holds the modular block securely to the gauge bar. A plurality of gauge holes extend from the bottom toward the top surface, in some cases passing through the modular block. Gauge elements with proximal ends adopted to be received within the gauge holes may be positioned with proper spacing in the block. Gauge elements that have the proximal end inserted into the block are securely positioned by pin-screws that enter the block below the tab on the rear surface. The pin-screws are positioned beneath the tab. In this fashion, the pin-screws can be accessed without removing the modular block from the gauge bar. When engaging rounded gauge elements such as tufting needles, the pin screws may advantageously have conical ends to hold the gauge elements by wedging or camming force. [0012] Accordingly, it is an object of the present invention to provide a tufting machine where the gauge elements of the tufting machine are accurately positioned within a modular block assembly. [0013] Another object of the present invention is to provide in a tufting machine, a system which can facilitate the rapid change over of one or more damaged gauge elements, reducing to a minimum the downtime of the tufting machine. [0014] Another object of the present invention is to provide in a modular block assembly, a system which can facilitate the rapid change over of individual damaged gauge elements, reducing the cost of repairing broken gauge elements and removing the need to replace entire modular blocks when a single gauge element becomes damaged. [0015] Other objects, features, and advantages of the present invention will become apparent from the following description when considered in conjunction with the accompanying drawing wherein like characters of reference designate corresponding parts throughout several views. BRIEF DESCRIPTION OF THE DRAWINGS [0016] [0016]FIG. 1 is a fragmentary perspective view of a modular block assembly with single looper modular blocks in place on a gauge bar. [0017] [0017]FIG. 2 is an exploded perspective view of the modular block assembly of FIG. 1 with modular blocks removed from the gauge bar, and one looper modular block disassembled. [0018] [0018]FIG. 3 is a perspective view of the rear surface of a modular block of FIG. 1. [0019] [0019]FIG. 4 is a fragmentary perspective view of a double looper modular block assembly with modular blocks in place on the gauge bar. [0020] [0020]FIG. 5 is an exploded perspective view of the modular block assembly of FIG. 4, with modular blocks removed from the gauge bar and one block disassembled. [0021] [0021]FIG. 6 is a fragmentary perspective view of a modular needle block assembly with modular blocks in place on a gauge bar. [0022] [0022]FIG. 7 is an exploded fragmentary perspective view of the modular needle block assembly of FIG. 6 with the modular blocks removed from the gauge bar and one block disassembled. [0023] [0023]FIG. 8 is a rear perspective view of a modular block of FIG. 6. [0024] [0024]FIG. 9 is an exploded perspective view of a modular assembly having a single row of loop-pile hooks held in place by a lateral pin and securing bolts. [0025] [0025]FIG. 10A is an exploded view of a modular block having a double row of loop-pile hooks held in place by lateral pins and securing bolts. [0026] [0026]FIG. 10B is a top perspective view of the relative positions of the gauge elements, lateral pins and securing bolts of FIG. 10A when mounted in the block. [0027] [0027]FIG. 10C is a bottom perspective view of the relative positions of the gauge elements, lateral pins and securing bolts of FIG. 10A when mounted in the block. [0028] [0028]FIG. 10D shows in isolation a side elevation view of the relative positions of a single gauge element, lateral pin and securing bolt when mounted in the block. [0029] [0029]FIG. 11A is an exploded view of a modular block having cut-pile hooks with lateral pins, and securing bolts. [0030] [0030]FIG. 11B is a side elevation view of the block of FIG. 11A. [0031] [0031]FIG. 11C is a side elevation view of the relative positions of the gauge elements, lateral pins and securing bolt of FIG. 11B when mounted in the block. DETAILED DESCRIPTION [0032] The present invention is designed for use in tufting machines of the type generally including a needle bar carrying one or more rows of longitudinally spaced needles that are supported and reciprocally driven by a plurality of push rods. In the tufting zone, the needles carry yarns which are driven through a backing fabric by the reciprocation of the needles. While penetrating the backing fabric, a plurality of longitudinally spaced hooks cooperate with the needles to seize loops of yarns and thereby form the face of a resulting fabric. In some cases the hooks will cooperate with knives to cut the loops of yarn seized on the hooks and thereby form a cut pile face for the fabric. The present invention is directed to modular units for holding loopers or hooks and for holding needles to facilitate their cooperation during the tufting process. [0033] Referring in detail to FIG. 1, a modular block assembly 5 is illustrated having a single row of gauge elements 10 , in this case loopers, housed in a series of modular blocks 15 . The individual gauge elements 10 are fastened to each block 15 by a lateral pin 20 . As better illustrated in FIG. 2, the lateral pin 20 enters the modular block 15 at one of the opposing side surfaces 22 a, 22 b. The gauge bar 25 and guide bar 30 are used in concert to position the modular blocks 15 relative to one another. The guide bar 30 extends laterally through channel 35 substantially the entire length of the gauge bar 25 . The tab breaks 115 of the modular blocks 15 engage with guide bar 30 as shown in FIG. 3, to vertically align the individual blocks 15 in the modular block assembly 5 . [0034] [0034]FIG. 2 illustrates a portion of the modular block assembly 5 with the blocks 15 detached from the gauge bar 25 . The gauge bar 25 has a plurality of vertical recesses 40 . The recesses 40 are crossed by lateral channel 35 so that guide bar 30 fits between the gauge bar 25 and the rear surfaces 45 of the modular blocks 15 . Guide bar 30 creates upper face 31 and lower face 32 which are normal to the side walls of recesses 40 . When tab breaks 115 of modular blocks 15 engage these faces 31 , 32 , the faces serve as restraining surfaces to hold blocks 15 in vertical alignment. [0035] One modular block 15 in FIG. 2 is disassembled and removed from the gauge bar 25 to reveal spaced parallel slots 50 divided by vertical walls 51 located on the front surface 55 of the block for receiving the proximal ends 75 of the gauge elements 10 . The illustrated proximal ends 75 of the gauge elements 10 contain apertures such as pinholes 70 . When the gauge elements 10 are positioned in the modular block 15 the pinholes 70 align with apertures formed in side surfaces of the block such as pin opening 85 . Lateral pin 20 is then inserted through pin opening 85 in one of the opposing side surfaces 22 a, 22 b, and the pinholes 70 for each gauge element 10 to fasten the gauge elements 10 in block 15 . [0036] In illustrated modular blocks 15 containing only a single row of gauge elements 10 , a tongue portion 60 extends from the rear surface 45 of the modular block 15 . The tongue 60 has an opening, preferably in the form of hole 90 , as shown in FIG. 3. When the modular block 15 is positioned on the gauge bar 25 , threaded hole 90 aligns with another hole 100 located in a gauge bar recess 40 . Once a modular block 15 is positioned a securing screw 65 can be inserted through hole 90 and tightened into the hole 100 on the gauge bar 25 . A modular block 15 , once fixed in place by the securing screw 65 , is prevented from lateral and vertical movement. The screw 65 and side walls of vertical recesses 40 resist against horizontal movement while the screw 65 and faces 31 , 32 of the guide bar 30 resist against vertical movement. The fixed position of the blocks 15 insures that the gauge elements 10 remain properly aligned during the tufting process. [0037] [0037]FIG. 3 shows the rear surface 45 of a modular block 15 having a single row of gauge elements 10 . On the rear surface 45 is a detent in the form of an elongated tab 110 extending vertically from the top 165 of the block to the bottom of the tongue portion 60 of the block. Tab 110 has a horizontal break 115 that engages with guide bar 30 to vertically position block 15 on the gauge bar 25 . The walls of break 115 are preferably substantially planar and parallel so that a part of the rectangular cross section of guide bar 30 closely fits within break 115 . The lower segment 120 of the tab contains the opening 90 where the securing screw 65 enters and attaches to a receiving hole 100 in the gauge bar 25 . [0038] [0038]FIG. 4 illustrates a section of a modular block assembly 5 with three double gauge element modular blocks 130 mounted on the gauge bar 26 . Each modular block 130 contains two transverse gauge element rows 125 , the forward gauge elements 12 forming a first row 125 and rear gauge elements 11 forming a second row. Modular blocks 130 have two apertures such as pin openings 85 a, 85 b that are spaced apart on the side surfaces 22 a, 22 b of the block 130 . Unlike blocks 15 in FIG. 1, a portion of the double gauge modular blocks 130 rests on top of the gauge bar 26 to vertically position blocks 130 . This is accomplished by using a downwardly extending detent such as tongue 60 illustrated near the center of the bottom 135 of blocks 130 . [0039] [0039]FIG. 5 shows an exploded view of modular block 130 containing two rows 125 of gauge elements 11 , 12 . The gauge bar 26 in FIG. 5 has a plurality of vertical recesses 40 . Vertical recesses 40 receive tongues 60 to horizontally position blocks 130 along the gauge bar 25 . Vertical positioning is accomplished by resting part of the bottom surface 135 of gauge blocks 130 on the top surface of gauge bar 25 . Modular block 130 in FIG. 5 is disassembled and removed from the gauge bar 26 to reveal the spaced parallel slots 50 a, 50 b located on the front 55 and rear surface 45 of the block 130 for receiving the proximal ends 77 , 78 of the front and rear gauge elements 12 , 11 . [0040] The proximal ends 77 , 78 of the gauge elements 12 , 11 contain openings such as pin holes 71 , 72 which when positioned in slots 50 a, 50 b of modular block 130 align with pin openings 85 a or 85 b, respectively. The lateral pins 20 a, 20 b are inserted through the pin openings 85 a or 85 b on one of the opposing side surfaces 22 a, 22 b and through pin holes 71 , 72 in the proximal ends of each gauge element 11 , 12 to fasten the gauge elements 11 , 12 in the modular block 130 . [0041] In the illustrated modular blocks 130 the tongue portion 60 of the modular block 130 extends centrally from the bottom surface 135 . Tongue 60 defines an opening (not shown). When modular blocks 130 are positioned on gauge bar 26 , this opening aligns with a threaded receiving hole 100 , located in vertical recesses 40 of gauge bar 26 . Once the modular block 130 is positioned a securing screw 65 can be inserted through the opening in tongue 60 and tightened into threaded receiving hole 100 . Modular blocks 130 , once fixed in place by securing screws 65 , are prevented from lateral movement by the securing screw 65 and interface of the detent against walls of vertical recesses. Similarly, modular blocks 130 are prevented from vertical movement by securing screw 65 and interface of bottom surface 135 against the top surface 26 a of gauge bar 26 . The fixed position of the block 130 insures that the gauge elements 11 , 12 remain properly aligned during the tufting process. [0042] Referring now to FIG. 6, another aspect of the present invention depicts a section of a modular block assembly 5 having a row of gauge elements, in this case needles 13 , housed in clamping modular blocks 140 . FIG. 6 shows four clamping modular blocks 140 attached to gauge bar 27 . The clamping modular blocks 140 are positioned such that the lower portion 150 of the block 140 extends beneath the gauge bar 27 . This exposed lower portion 150 contains individual clamping elements, such as screw-pins 145 , shown in FIG. 7, that hold the gauge elements 13 in place in the block 140 . The gauge bar 27 has a horizontal shelf portion 27 a and a vertical portion 27 b which join to form an interior right angle into which the blocks 140 are positioned. [0043] [0043]FIG. 7 illustrates a portion of a modular block assembly 5 with screw-pin modular blocks 140 detached from the gauge bar 27 and one block 140 disassembled. The gauge bar 27 has a plurality of vertical recesses 40 on the inner surface of vertical portion 27 b of the gauge bar 27 . As illustrated, the recesses 40 do not extend the entire height of the wall portion 27 b of the gauge bar 27 . Each recess 40 preferably contains a clearance hole 100 which receives a securing screw 65 to attach blocks 140 to the gauge bar 27 . The rear surfaces 45 of modular blocks 140 have a detent such as tab 160 with an opening, such as threaded hole 90 (shown in FIG. 8), positioned to align with holes 100 , located in the vertical recesses 40 of gauge bar 27 . Once a modular block 140 is positioned in the interior right angle between the shelf portion 27 a and wall portion 27 b, with tab 160 received in a vertical recess 40 , the securing screw 65 can be inserted through the corresponding hole 100 in the wall portion 27 b into the threaded hole 90 in the tab 160 and tightened to hold the modular block 140 in place. Once fixed in place by securing screw 65 , the modular block 140 is prevented from lateral movement by the action of the tab 160 fitting between the vertical walls of the vertical recess 40 , by the screw 65 . Vertical movement is restrained by action of the screw 65 and the interface of the top surface 165 of block 140 with the bottom of shelf portion 27 a of the gauge bar 27 . The fixed position of the block 140 insures that the gauge elements 10 remain properly aligned during the tufting process. [0044] [0044]FIG. 7 also depicts a disassembled clamping modular block 140 thereby revealing the spaced parallel gauge element openings 155 which extend from the top surface 165 to the bottom surface 135 of the block 140 . Openings 155 need not extend completely to the top surface 165 for satisfactory operation, however, it is convenient for manufacture. The individual needles 13 are fastened to the block 140 by dedicated clamps such as screw-pins 145 that fix individual gauge elements 10 within the block 140 . Screw pins 145 enter the block 140 at the rear surface 45 of the block 140 on its lower portion 150 . When the block is attached to the gauge bar 27 the screw-pins 145 remain accessible so that individual gauge elements 10 can be removed and replaced. [0045] [0045]FIG. 8 illustrates the top 165 and rear surface 45 of the block 140 . Gauge element openings 155 can be seen on the top surface 165 of the block 140 . A rectangular tab 160 for positioning the block 140 on the gauge bar 27 is located centrally on the rear surface 45 of the block 140 . The rectangular tab 160 defines the opening 90 which aligns with the holes 100 in vertical recesses 40 and with securing screw 65 fixes the block 140 to the gauge bar 27 . Openings 170 for screw pins 145 are located horizontally along the lower portion 150 of block 140 . [0046] Referring now to FIG. 9, a preferred embodiment of the present invention depicts a modular block assembly 5 having a single row of gauge elements, in this case loop pile hooks 10 , housed in a single gauge modular block 15 . The modular block 15 may be mounted and attached to the gauge bar 25 with securing screw 65 extending through the block 15 into the gauge bar 25 . The gauge elements 10 are inserted in and removably secured to the block 15 by use of lateral pin 20 . The lateral pin 20 may be divided into two or more sections, or be formed of somewhat malleable material, to compensate for various differences in the heights of the gauging elements 10 . [0047] Unlike the previous embodiments, the illustrated lateral pin 20 does not extend through openings in the gauge elements 10 , but merely abuts proximal ends of gauge elements 10 so that the gauge elements 10 are resting on the lateral pin 20 . The lateral pin 20 is then biased against the gauging elements 10 by a clamp such as securing bolt 38 received in threaded opening 39 on the top surface 165 of modular block 15 . Tightening securing bolts 38 biases the lateral pin 20 against the gauging elements 10 . In a preferred embodiment the lateral pin 20 is made of a soft metal such as brass so that when urged by the securing bolt 38 , the lateral pin 20 deforms slightly and compresses within channels 79 of individual gauge elements 10 . As a result of the clamp, the lateral pin 20 is held in place preventing lateral movement of the pin 20 into or out of the block 15 . [0048] Due to differences in the width of the proximal ends 75 and channels 79 of the various gauge elements 10 , varying amounts of pressure are required along the length of pin 20 to sufficiently compress and restrain the gauge elements in a fixed position. Thus a preferred construction divides the pin 20 into segments to prevent the necessity of compressing a single pin 20 into all the gauge elements 10 . [0049] This method of securing gauging elements to a block may also be employed for double gauge modular blocks 130 as seen in FIG. 10A. Rear and forward gauging elements 11 and 12 are arranged in parallel transverse rows on block 130 . The rear row of gauging elements 11 is held in position by rear lateral pin 20 a. Pin 20 a is biased against the rear gauging elements 11 by securing bolts 38 a which are received by threaded openings 39 a. Likewise, the forward gauging elements 12 are held in place by forward lateral pin 20 b biased against the forward gauging elements 12 by securing bolts 38 b which are received by threaded openings 39 b. [0050] In FIGS. 10B and 10C, the gauge elements 11 , 12 are shown with lateral pins 20 a, 20 b and securing bolts as they would be positioned in blocks 130 , however, the blocks are not shown. Of particular interest is the conical point 89 of securing bolts 38 a, 38 b. The conical points 89 are aligned alightly off center of lateral pins 20 a, 20 b, so that the side wall rather than the vertice of the conical point makes contact with the pins 20 a, 20 b. This causes a wedge like or camming effect to pressure pins 20 a, 20 b against gauge elements 11 , 12 . When securing bolts 38 a, 38 b utilize camming action rather than mere frontal clamping pressure as would typically be the case if the bolts had flat ends, the bolts 38 a, 38 b will continue to function even when wear and operating stresses have introduced some play between the threads of the bolts 38 a, 38 b and their openings 38 a, 39 b. [0051] [0051]FIG. 10D shows a single securing bolt 38 a with conical point 89 applying camming type pressure against lateral pin 20 a which is engaged in channel 79 of rear gauge element 11 . The modular block 130 that would hold these components is not shown so that the interaction of the gauge element, lateral pin 20 a and securing bolt 38 a can be clearly illustrated. [0052] An additional embodiment of the invention is illustrated in FIG. 11A. The gauge elements, in this case cut-pile loopers 14 , 18 are shown removed from block 15 . When mounted in block 15 , the gauge elements 14 , 18 fit between lateral bracing pins 16 a, 16 b and secured lateral pin 20 . The bracing pins 16 a, 16 b, are slidably press fit within the block 15 and then gauge elements 14 , 18 are positioned. Bracing pins 16 a, 16 b preferably fit in channels 79 a, 79 b (shown in FIG. 11C) of gauge elements 14 , 18 . Pin 20 is also biased against the gauge elements 14 , 18 by a clamping device such as securing bolts 38 proceeding through threaded openings 39 to engage the pin 20 . Once the gauge elements 14 , 18 are placed in the block 15 and the bracing pins 16 a, 16 b are positioned in channels 79 a, 79 b of those gauge elements 14 , 18 and lateral pin 20 is in place in block 15 , the securing bolts 38 are tightened to bias the securing pin 20 against the gauge elements 14 , 18 . [0053] [0053]FIG. 11A shows a series of four securing bolts 38 . In a preferred embodiment, each securing bolt 38 contacts a dedicated segment of the pin 20 . Pin 20 may be made of a malleable metal such as brass and either cut or scored to create segments. Thus, pin 20 may be comprised of four separate pieces. The bolts 38 are sufficiently spaced across the block 15 so that each securing bolt 38 can contact a segment of the securing pin 20 and thereby bias between about two and about four individual gauge elements 14 , 18 . [0054] [0054]FIGS. 11B and 11C are side plan views of the modular block 15 and cut pile loopers 14 , 18 of FIG. 11A, however, FIG. 11C shows the gauge elements 14 , 18 , lateral pins 16 a, 16 b, 20 , and securing bolts 38 without the modular block 15 . It can be seen that cut pile loopers 14 , 18 are designed to engage with rear and front rows of needles respectively, although a single length of looper could be used if only one row of needles was to be used to create cut pile tufts. As best seen in FIG. 11B, the side wall of conical point 89 exerts camming pressure against lateral pin 20 . Lateral pin 20 in turn engages with the proximal ends of gauge elements 14 , 18 . FIG. 11C shows that lateral pins 16 a, 16 b and 20 are advantageously set in channels 79 a, 79 b, 79 formed in the proximal ends of the gauge elements 14 , 18 . [0055] Although a preferred embodiment of the present invention has been disclosed in detail herein, it will be understood that various substitutions and modifications may be made to the disclosed embodiment described herein without departing from the scope and spirit of the present invention as recited in the appended claims.

Lateral pins are used to provide a tufting machine modular gauge assembly that allows damaged or broken gauge elements to be replaced individually. The modular gauge assembly consists of a gauge bar with a plurality of modular blocks removably attached to the bar. The modular blocks are six sided with a detent and fastener mechanism for attaching the block to the gauge bar. The gauge elements may be attached to the block by dedicated screw-pins or by a lateral pin that passes through all the gauge elements within a block. The lateral pin may either pierce the gauge elements or abut the gauge elements. Abutting pins may be It malleable and segmented and secured in position by conical ended bolts.

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Application No. 61/722,699 entitled HEAVY DUTY, LEVERAGED SPARE TIRE CARRIER and filed on Nov. 5, 2012, which is specifically incorporated by reference herein for all that it discloses and teaches. TECHNICAL FIELD [0002] The present invention relates generally to the field of motor vehicles; more particularly, to large, recreational-vehicle-type motor vehicles; and more particularly still, to a heavy duty, leveraged spare tire carrier that can be installed on a receiver hitch commonly found on recreational vehicles and is actuatable by a single person. BACKGROUND [0003] Motor vehicles have been in common usage for nearly a century. Shortly after the first, rather small, personal automobiles were rolling off assembly lines, larger trucks and related vehicles began to be produced in large numbers as well. Towable trailers equipped with living quarters soon followed, and it wasn't long before such trailers were placed on a truck chassis and the recreational vehicle (“RV”) or motorhome was born. Today, such vehicles can be exceedingly large, requiring huge, heavy tires (in comparison to a standard automobile tire). Such tires, especially when affixed to a wheel and ready to be installed on the motorhome in place of a flat tire (such wheel and tire assemblies are ubiquitously referred to as spare tires), can weigh in excess of one hundred pounds and are quite unwieldy and difficult to handle. Perhaps for these reasons, many motorhomes and other large RVs often do not carry a spare tire. Thus, if the driver of such a vehicle is unfortunate enough to experience a flat tire, his or her only option is to call for assistance. Because recreational vehicles are often used to recreate in far-flung locations, assistance can be a long distance away, difficult to procure, and often very expensive, if available at all. [0004] Most small motor vehicles (such as cars and light trucks) carry a spare tire either in the trunk, under the chassis, or otherwise attached to the automobile so that, in the case of a flat tire, the operator can remove the flat, install the spare tire, and drive the vehicle to a repair station for further assistance. Because many motorhome owners are familiar with this state of affairs when operating their smaller automobiles, they lament the fact that such a spare tire assembly is too big and heavy to be commonly installed in recreational vehicles and are often completely unprepared to deal with a flat tire if such occurs while they are operating their RV. [0005] Since many manufacturers of RVs do not include a spare tire or even a mounting location for an owner to carry an after-market spare tire with them, there is currently a need for an RV spare tire carrier. However, as noted above, spare tires for RVs are exceedingly heavy and unwieldy, so spare tire carriers, as currently known in the art, are not built heavy enough to handle such spares and can not just be welded onto an RV because a single person could be crushed trying to remove a spare tire therefrom. Instead, what is needed is a heavy duty, leveraged spare tire carrier than can be easily installed onto almost all RVs, is strong enough to carry the weight and bulk of an RV spare tire, and yet is configured in such a way as to allow a single person to load and unload the spare tire from the carrier without risking life and limb in the process. SUMMARY [0006] One embodiment of the present invention comprises a heavy duty, cross or T-shaped frame configured so a spare tire for an RV can be bolted thereto and mounted on a receiver-type hitch common in the RV industry with a secondary receiver hitch mounted thereon, and having an integral lever-actuated lifting and lowering apparatus to allow a single person the ability to remove and replace a spare tire on the carrier and/or to swing the carrier and spare tire out of the way so an engine or other compartment in the rear of an RV can still be accessed. BRIEF DESCRIPTION OF THE DRAWINGS [0007] The aforementioned and other features and objects of the present invention and the manner of attaining them will become more apparent and the invention itself will be best understood by reference to the following descriptions of a preferred embodiment and other embodiments taken in conjunction with the accompanying drawings, wherein: [0008] FIG. 1 illustrates a front elevation view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier with a spare tire attached; [0009] FIG. 2 illustrates a rear elevation view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier with a spare tire attached; [0010] FIG. 3 illustrates a bottom plan view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier with a spare tire attached; [0011] FIG. 4 illustrates a top plan view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier with a spare tire attached; [0012] FIG. 5 illustrates a left side elevation view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier with a spare tire attached; [0013] FIG. 6 illustrates a front perspective view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier without a spare tire mounted thereon and placed in the upright, travelling position; and [0014] FIG. 7 illustrates a front perspective view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier without a spare tire mounted thereon and lowered into a horizontal, non-travelling position. DETAILED DESCRIPTION [0015] Referring now to the drawings, FIG. 1 illustrates a front elevation view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier 100 with a spare tire 170 attached thereto. Note that in FIG. 1 , the spare tire 170 includes both common components: the tire 171 already mounted onto the rim or wheel 172 . Throughout this document, whenever a reference is made to a spare tire 170 , it includes both a tire 171 and a wheel 172 , unless otherwise described. The carrier 100 shown in FIG. 1 is mostly hidden behind the spare tire 170 ; reference to later drawing FIGs. is recommended. [0016] The wheel 172 includes a plurality of mounting points 174 (often numbering ten on many RV wheels, as shown in FIG. 1 , but other numbers are contemplated). In the embodiment illustrated in FIG. 1 , there are four mounting bolts 176 , 177 , 178 and 179 illustrated utilizing four of the plurality of mounting points 174 . In other embodiments, the number of mounting bolts may be higher or lower than that shown in FIG. 1 . The mounting bolts 176 - 179 serve to removably affix the spare tire 170 to the carrier 100 . [0017] The front hinge bracket 131 can be seen below the spare tire 170 in FIG. 1 . The main body of the carrier 100 hinges on the hinge bolt 140 that runs through the front hinge bracket 131 and the rear hinge bracket (not shown in FIG. 1 , see item 232 in FIG. 2 ). In order to mount the carrier 100 onto the RV, a draw bar 120 is affixed to the carrier 100 . Because installation of a draw bar 120 into the receiver hitch opening on an RV blocks usage of said receiver hitch, a secondary receiver hitch 110 is installed on the carrier 100 itself to allow for use of other draw bars so that the RV can still tow trailers, etc. while the heavy duty, leveraged spare tire carrier 100 is installed on the RV. Once the draw bar 120 is inserted into the receiver hitch on the RV, a hitch pin bolt 150 and nut (or other securing device) secures it therein. [0018] A leverage handle 160 is also partially shown in FIG. 1 . This implement is installed near the top of the main body of the carrier 100 when a person wishes to raise or lower the spare tire 170 . See later drawing FIGs. for additional descriptions of the leverage handle 160 . [0019] FIG. 2 illustrates a rear elevation view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier 200 with a spare tire 270 attached thereto. As in FIG. 1 , the spare tire 270 includes both the tire 271 and the wheel 272 with the tire mounted thereon. Since FIG. 2 is a rear view, the carrier 200 can be more clearly seen than in FIG. 1 . [0020] The wheel 272 includes a plurality of mounting points 274 . In the embodiment illustrated in FIG. 2 , there are four mounting bolts 276 , 277 , 278 and 279 illustrated utilizing four of the plurality of mounting points 274 . The mounting bolts 276 - 279 serve to removably affix the spare tire 270 to the carrier 200 . [0021] The front hinge bracket is not shown in FIG. 2 , see FIG. 1 , item 131 . The rear hinge bracket 232 is shown. Together, the two hinge brackets form a set of upright members affixed to the draw bar 220 . Vertical support members 222 and 224 are affixed to the draw bar 220 , the rear hinge bracket 232 , and the secondary receiver hitch 210 . These support members 222 and 224 strengthen the carrier 200 so that it can securely hold the spare tire 270 while withstanding the large forces exerted on the secondary receiver hitch 210 when a heavy trailer is attached to the RV via the carrier 200 . [0022] The main body of the carrier 200 can hinge or swing downwards from the upright position shown in FIG. 2 into a lowered position (see FIG. 7 ) so that a person can access the rear of the RV and/or can remove the spare tire 270 from the carrier 200 . The hinge bolt 240 extends through the two upright hinge brackets 131 and 232 , as well as the vertical member 290 of the main body of the carrier 200 . A release pin 234 is attached to at least one of the upright hinge brackets 131 and 232 and ensures that the vertical member 290 stays in an upright position until the release pin 234 is actuated, releasing the vertical member 290 from its position between the hinge brackets 131 and 232 . Once released, the vertical member 290 can hinge on the hinge bolt 240 and be swung down to either side of the carrier 200 . See later FIGs. for more detail on the hinge mechanism. [0023] The vertical member 290 can be manufactured from square steel tubing as shown in FIG. 2 . In other embodiments, other metals or materials of sufficient strength can be utilized. In yet other embodiments, the vertical member 290 can be solid and it can have other cross-sectional shapes besides square. In FIG. 2 , two of the mounting bolts 279 and 277 are attached to the vertical member 290 and the remaining two mounting bolts 278 and 276 are attached to the horizontal member 280 . The horizontal member 280 is attached to the vertical member 290 and generally extends perpendicular thereto, with approximately half of the horizontal member 280 extending to the left of the vertical member 290 and approximately half of the horizontal member 280 extending to the right. The horizontal member 280 can be manufactured from square steel tubing as shown in FIG. 2 , but like the vertical member 290 , in other embodiments, the horizontal member 280 can be manufactured from other metals or materials of sufficient strength and it can be solid and/or have a cross-sectional shape besides a square (for example, rectangular, round, oval, hexagonal, or other shapes of tubing or solid material can be employed). In order to enhance the strength of the horizontal and vertical members 280 and 290 and the connection therebetween, a plurality of angle supports 282 can be attached at each corner of the joint between the members 280 and 290 . As shown in FIG. 2 , the plurality of angle supports 282 can be triangular shaped metal pieces that are welded or otherwise connected to the horizontal member 280 and vertical member 290 . In other embodiments, the number of angle supports 282 can be one, two, three, four, or none. [0024] In order to mount the carrier 200 onto the RV, a draw bar 220 is affixed to the carrier 200 . Because installation of a draw bar 220 into the receiver hitch opening on an RV blocks usage of said receiver hitch, a secondary receiver hitch 210 is affixed on the carrier 200 below the draw bar 220 . The secondary receiver hitch 210 allows for use of other draw bars so that the RV can still tow trailers, etc. while the heavy duty, leveraged spare tire carrier 200 is installed on the RV. Once the draw bar 220 is inserted into the receiver hitch on the RV, a hitch pin bolt 250 and nut (or other securing device) secures it therein. [0025] An exemplary leverage handle 260 is shown in FIG. 2 . This implement is installed in leverage attachment point 275 located near the top of the vertical member 290 when a person wishes to raise or lower the spare tire 270 . The leverage handle 260 can be threaded into the leverage attachment point 275 , can be simply slid into the leverage attachment point 275 , or some other attachment mechanism can be employed so that the leverage handle 260 can act on the vertical member 290 . Regardless of the means of attachment, the leverage handle 260 allows a single person to lower and raise the spare tire 270 by hinging the vertical member 290 on the hinge bolt 240 . Because the leverage handle 260 extends the distance between the hinge bolt 240 and the location at which a user exerts force against the vertical member 290 , significant leverage is gained, thereby allowing a single person to raise and lower the extremely heavy spare tire 270 with ease. See later drawing FIGs. for additional descriptions of the leverage handle 260 , hitch pin bolt 250 and hinging mechanism. In another embodiment the leverage attachment point is attached to the horizontal member such that the leverage handle can be attached to the horizontal member and can act upon the horizontal member in order to raise or lower the spare tire. [0026] FIG. 3 illustrates a bottom plan view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier 300 with a spare tire 370 attached thereto. The relative position of the tire 371 and the wheel 372 can be seen more clearly from this viewing angle. Also, the attachment bolts 376 and 378 can be seen extending through the horizontal member 380 and attaching the wheel 372 to the horizontal member 380 . The attachment bolts that attach the wheel to the vertical member are not visible in this view. [0027] The body of the secondary receiver hitch affixed to the bottom of the carrier 300 can be clearly seen in FIG. 3 . Above it, the draw bar 320 extends perpendicular to the horizontal member 380 and the hitch pin bolt 350 can be seen extending through the draw bar 320 . It should be apparent that when the draw bar 320 is inserted into the receiver hitch on an RV, the hitch pin bolt 350 would pass through the receiver hitch and through the draw bar 320 , securing the draw bar 320 inside the receiver hitch. In FIG. 3 , the hitch pin bolt 350 is shown as a hexagonal headed bolt with a nut and a hole running through the hitch pin bolt 350 , providing a location through which a pin or other securing mechanism can be placed in order to ensure that the nut can not inadvertently rotate off of the bolt 350 . In other embodiments, other types of hitch pin bolts 350 as known in the art can be employed (e.g., locking hitch pins, L handled pins, T handled pins, etc.). [0028] The bottom portions of the hinge brackets 331 and 332 can be seen in FIG. 3 . See later FIGs. for more detail of the hinge brackets 331 and 332 . Also illustrated in FIG. 3 is the leverage handle 360 . Because FIG. 3 provides a bottom view and the leverage handle 360 is depicted standing vertically, only the bottom portion of the leverage handle 360 is visible. In the embodiment in FIG. 3 , the leverage handle 360 appears to have an outer perimeter that is circular-shaped; in other embodiments, the leverage handle 360 can have an outer perimeter that is shaped like a square, triangle, oval, or any other shape. Although not shown in FIG. 3 , the leverage attachment point should be shaped to match so that the leverage handle 360 can be inserted therein or otherwise attached thereto. [0029] FIG. 4 illustrates a top plan view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier 400 with a spare tire 470 attached. In this view, the leverage attachment point 475 can be seen extending from the top of the vertical member 490 . The top mounting bolt 477 can be seen as can the two side mounting bolts 476 and 478 . The mounting bolts extend through the vertical member 490 or horizontal member 480 (depending on the particular bolt) and attach the wheel 472 to the members 480 and 490 . The angle supports 482 can be seen running between the vertical member 490 and the horizontal member 480 . [0030] Below the top mounting bolt 477 , the rear hinge bracket 432 can be seen as can the release pin 434 . The vertical support members 422 and 424 are illustrated. As discussed above, the vertical support members 422 and 424 attach to the vertical member 490 , the draw bar 420 and the secondary receiver hitch (not shown in FIG. 4 , see FIG. 3 , item 310 ). An exemplary hitch pin bolt 450 is also illustrated as is the top surface of the leverage handle 460 . [0031] FIG. 5 illustrates a left side elevation view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier 500 with a spare tire 570 (including tire 571 and wheel 572 ) attached. When viewed from the side, the placement of the vertical member 590 between the front hinge plate 531 and the rear hinge plate 532 can be clearly seen. When the release pin 534 is actuated, the vertical member 590 can then hinge on the hinge bolt 540 , causing the spare tire 570 to swing downwards from its upright position. The positions of the horizontal member 580 and angle supports 582 relative to the vertical member 590 are illustrated in FIG. 5 as are the mounting bolts 577 , 578 and 579 (the fourth mounting bolt 476 is not visible in FIG. 5 , see FIG. 4 ). [0032] Portions of the leverage handle 560 can be seen, but as it is positioned generally on the other side of the assembly, it is mostly hidden in FIG. 5 . The leverage attachment point 575 can, however, be seen near the top of the vertical member 590 [0033] The side view of FIG. 5 provides a clear presentation of the vertical support member 524 and it should be obvious that the vertical support member 524 connects to all of the rear hinge plate 532 , the draw bar 520 , and the secondary receiver hitch 510 , thereby enhancing the structural integrity and strength of the assembly. FIG. 5 also shows the front and rear hinge brackets 531 and 532 attaching to both the draw bar 520 and the secondary receiver hitch 510 , providing additional strength and support such that a trailer can be connected to the secondary receiver hitch 510 and be fully supported by the carrier 500 . [0034] The secondary receiver hitch 510 is illustrated in FIG. 5 with a hitch pin hole 512 and a receiver hitch opening 514 , important features in a receiver hitch assembly. In order to use this assembly, a second draw bar would be inserted into the mouth of the receiver hitch opening 514 and a hitch pin would then be inserted through the hitch pin hole 512 and through the second draw bar, securing the second draw bar within the secondary receiver hitch 510 . [0035] FIG. 6 illustrates a front perspective view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier 600 without a spare tire mounted thereon and placed in the upright, travelling position. With the removal of the spare tire from the carrier 600 , most of the components can be seen more clearly. [0036] In the embodiment illustrated in FIG. 6 , there are four mounting bolts 676 , 677 , 678 and 679 that can be used to attach the wheel of the spare tire to the carrier 600 . In other embodiments, the number of mounting bolts 676 - 679 can vary from the four shown in FIG. 6 . The mounting bolts are attached to the vertical member 690 and the horizontal member 680 . This distributes the weight of the spare tire across the two members, ensuring that the carrier 600 can securely hold the large and unwieldy weight of an RV spare tire assembly. The perspective view of FIG. 6 clearly illustrates the relative positions of the vertical member 690 and the horizontal member 680 as well as the angle supports 682 that enhance the strength of the connections therebetween. [0037] Near the top of the vertical member 690 is the leverage attachment point 675 to which the leverage handle 660 attaches. The leverage handle 660 is illustrated in FIG. 6 as having a grip 661 to ensure that a user has a secure means of gripping the leverage handle 660 when using it to lower or raise the carrier 600 . [0038] The front hinge bracket 631 and rear hinge bracket 632 are shown in FIG. 6 . Together, the two hinge brackets form a set of upright members affixed to the draw bar 620 and the secondary receiver hitch 610 . Vertical support members 422 (not visible in FIG. 6 , see item 422 in FIG. 4) and 624 are affixed to the draw bar 620 , the rear hinge bracket 632 , and the secondary receiver hitch 610 . These support members 422 and 624 strengthen the carrier 600 so that it can securely hold the spare tire while withstanding the large forces exerted on the secondary receiver hitch 610 when a heavy trailer is attached to the RV via the carrier 600 . [0039] The main body of the carrier 600 can hinge or swing downwards from the upright position shown in FIG. 6 into a lowered position (see FIG. 7 ) so that a person can access the rear of the RV and/or can remove the spare tire from the carrier 600 . The flat tire from the RV can then be placed on the carrier 600 or the spare tire can be replaced thereon. The hinge bolt 640 extends through the two upright hinge brackets 631 and 632 , as well as the vertical member 690 of the main body of the carrier 600 . A release pin 634 is attached to at least one of the upright hinge brackets 631 and 632 (in the embodiment shown in FIG. 6 , the release pin 634 is shown as penetrating completely through both brackets) and ensures that the vertical member 690 stays in an upright position until the release pin 634 is actuated, thereby releasing the vertical member 690 from its vertical position between the hinge brackets 631 and 632 . Once released, the vertical member 690 can hinge on the hinge bolt 640 and be swung down to either side of the carrier 600 . In order to actuate the release pin 634 a security pin 635 must first be removed from the distal end of the release pin 634 . In other embodiments, other types of release pins 634 are contemplated (for example, a spring actuated release pin 634 could be employed wherein the spring keeps the pin 634 snuggly seated through the rear hinge bracket 632 until the release pin 634 is pulled sharply away from the rear hinge bracket 632 , drawing the release pin 634 out of the vertical member 690 so it can swing down; when the release pin 634 is released, the spring brings the release pin 634 back through the rear hinge bracket 632 and into engagement with the vertical member 690 , securing it in its upright position). [0040] The vertical member 690 can be manufactured from square steel tubing as shown in FIG. 6 . In other embodiments, other metals or materials of sufficient strength can be utilized. In yet other embodiments, the vertical member 690 can be solid and it can have other cross-sectional shapes besides square. In FIG. 6 , two of the mounting bolts 679 and 677 are attached to the vertical member 690 and the remaining two mounting bolts 678 and 676 are attached to the horizontal member 680 . The horizontal member 680 is attached to the vertical member 690 and generally extends perpendicular thereto, with approximately half of the horizontal member 680 extending to the left of the vertical member 690 and approximately half of the horizontal member 680 extending to the right. The horizontal member 680 can be manufactured from square steel tubing as shown in FIG. 6 , but like the vertical member 690 , in other embodiments, the horizontal member 680 can be manufactured from other metals or materials of sufficient strength and it can be solid and/or have a cross-sectional shape besides a square (for example, rectangular, round, oval, hexagonal, or other shapes of tubing or solid material can be employed). In order to enhance the strength of the horizontal and vertical members 680 and 690 and the connection therebetween, a plurality of angle supports 682 can be attached at each corner of the joint between the members 680 and 690 . As shown in FIG. 6 , the plurality of angle supports 682 can be triangular shaped metal pieces that are welded or otherwise connected to the horizontal member 680 and vertical member 690 . In other embodiments, the number of angle supports 682 can be none, one, two, three, four, or more. [0041] In order to mount the carrier 600 onto the RV, a draw bar 620 is affixed to the carrier 600 . Because installation of a draw bar 620 into the receiver hitch opening on an RV blocks usage of said receiver hitch, a secondary receiver hitch 610 is affixed on the carrier 600 below the draw bar 620 . The secondary receiver hitch 610 allows for use of other draw bars so that the RV can still tow trailers, etc. while the heavy duty, leveraged spare tire carrier 600 is installed on the RV. Once the draw bar 620 is inserted into the receiver hitch on the RV, a hitch pin bolt 650 and nut (or other securing device) secures it therein. [0042] An exemplary leverage handle 660 is shown in FIG. 6 . This implement is installed in leverage attachment point 675 located near the top of the vertical member 690 when a person wishes to raise or lower the spare tire 670 . The leverage handle 660 can be threaded into the leverage attachment point 675 , can be simply slid into the leverage attachment point 675 , or some other attachment mechanism can be employed so that the leverage handle 660 can act on the vertical member 690 . Regardless of the means of attachment, the leverage handle 660 allows a single person to lower and raise the spare tire 670 by hinging the vertical member 690 on the hinge bolt 640 . Because the leverage handle 660 extends the distance between the hinge bolt 640 and the location at which a user exerts force against the vertical member 690 , significant leverage is gained, thereby allowing a single person to raise and lower the extremely heavy spare tire 670 with ease. See FIG. 7 for additional descriptions of the leverage handle 660 , hitch pin bolt 650 and hinging mechanism. [0043] The secondary receiver hitch 610 is illustrated in FIG. 6 with a hitch pin hole 612 and a receiver hitch opening 614 , important features in a receiver hitch assembly. In order to use this assembly, a second draw bar would be inserted into the mouth of the receiver hitch opening 614 and a hitch pin would then be inserted through the hitch pin hole 612 and through the second draw bar, securing the second draw bar within the secondary receiver hitch 610 . [0044] FIG. 7 illustrates a front perspective view of an exemplary embodiment of a heavy duty, leveraged spare tire carrier 700 without a spare tire mounted thereon and lowered into a horizontal, non-travelling position. The leverage handle 760 is shown in its active position, attached to the vertical member 790 . By grasping the grip 761 , a user can take advantage of the leverage gaining benefits of moving the point of application of force further out from the fulcrum (here, the fulcrum is the hinge bolt 740 ). The amount of force required to raise or lower the spare tire is much reduced when that force is applied to the grip 761 of the leverage handle 760 versus if it was applied directly to the vertical member 790 itself. [0045] The front and rear hinge brackets 731 and 732 are illustrated in FIG. 7 with the release pin removed, allowing the vertical member 790 to swing downwards on the hinge bolt 740 . Note that the carrier 700 is designed such that the vertical member 790 can swing either left or right in the embodiment shown in FIG. 7 . In other embodiments, it may be useful to limit the direction of swing to one or the other. [0046] Depending on the height of the RV's receiver hitch, once the vertical member 790 is swung downwards, a spare tire attached to the vertical member 790 will now be resting on the ground. The spare can then be detached from the carrier 700 and rolled away without the user having to lift and/or wrangle the large and weighty tire. The RV's flat tire can then be rolled to the carrier, attached thereto, and the vertical member 790 and flat tire can then be swung back up and into place using the leverage handle 760 . [0047] While particular embodiments of the invention have been described and disclosed in the present application, it should be understood that any number of permutations, modifications, or embodiments may be made without departing from the spirit and scope of this invention. Accordingly, it is not the intention of this application to limit this invention in any way except as by the appended claims. [0048] Particular terminology used when describing certain features or aspects of the invention should not be taken to imply that the terminology is being redefined herein to be restricted to any specific characteristics, features, or aspects of the invention with which that terminology is associated. In general, the terms used in the following claims should not be construed to limit the invention to the specific embodiments disclosed in the specification, unless the above “Detailed Description” section explicitly defines such terms. Accordingly, the actual scope of the invention encompasses not only the disclosed embodiments, but also all equivalent ways of practicing or implementing the invention. [0049] The above detailed description of the embodiments of the invention is not intended to be exhaustive or to limit the invention to the precise embodiment or form disclosed herein or to the particular field of usage mentioned in this disclosure. While specific embodiments of, and examples for, the invention are described above for illustrative purposes, various equivalent modifications are possible within the scope of the invention, as those skilled in the relevant art will recognize. Also, the teachings of the invention provided herein can be applied to other systems, not necessarily the system described above. The elements and acts of the various embodiments described above can be combined to provide further embodiments. [0050] In light of the above “Detailed Description,” the Inventor may make changes to the invention. While the detailed description outlines possible embodiments of the invention and discloses the best mode contemplated, no matter how detailed the above appears in text, the invention may be practiced in a myriad of ways. Thus, implementation details may vary considerably while still being encompassed by the spirit of the invention as disclosed by the inventor. As discussed herein, specific terminology used when describing certain features or aspects of the invention should not be taken to imply that the terminology is being redefined herein to be restricted to any specific characteristics, features, or aspects of the invention with which that terminology is associated. [0051] While certain aspects of the invention are presented below in certain claim forms, the inventor contemplates the various aspects of the invention in any number of claim forms. Accordingly, the inventor reserves the right to add additional claims after filing the application to pursue such additional claim forms for other aspects of the invention. [0052] The above specification, examples and data provide a description of the structure and use of exemplary implementations of the described articles of manufacture and methods. It is important to note that many implementations can be made without departing from the spirit and scope of the invention.

A heavy duty, leveraged spare tire carrier utilizes a cross or T-shaped frame configured so a spare tire for an recreational vehicle can be bolted thereto and mounted on a receiver-type hitch common in the RV industry with a secondary receiver hitch mounted thereon. The carrier has an integral lever-actuated lifting and lowering apparatus to allow a single person the ability to remove and replace a spare tire on the carrier and/or to swing the carrier and spare tire out of the way so an engine or other compartment in the rear of an RV can still be accessed.

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a method for efficiently encoding/decoding images using depth information and an encoding/decoding apparatus and image system using the same. [0003] 2. Related Art [0004] Depth information images are widely used in three-dimensional video encoding, and a depth information camera equipped in new input devices, such as Kinect camera, may be utilized in various 3D applications. [0005] Meanwhile, the 3D applications may become commonplace through a diversity of 2D/3D application services, and accordingly, as depth information cameras are included in multimedia camera systems in the future, various types of information may be utilized. SUMMARY OF THE INVENTION [0006] The present invention aims to provide an image encoding and decoding method that may increase encoding efficiency while reducing complexity using depth information and an encoding/decoding apparatus and image system using the same. [0007] To achieve the above objects, according to an embodiment of the present invention, a method for decoding an image comprises receiving encoded data; extracting depth information from the encoded data; decoding the encoded data using the depth information; and obtaining a 2D normal image from the decoded data using the depth information. [0008] To achieve the above objects, according to an embodiment of the present invention, a method for decoding an image comprises receiving encoded data; obtaining object information for separating objects in the image into predetermined units depending on the depth information from a header of the encoded data; decoding the encoded data using the obtained object information; and obtaining a 2D normal image from the decoded data using the depth information. [0009] To achieve the above objects, according to an embodiment of the present invention, a method for decoding an image comprises receiving encoded data; parsing type information for identifying a type of a network abstraction layer unit included in the encoded data; in a case where the parsed type information is associated with an object map, obtaining an object map from the encoded data; and decoding an image bitstream from the encoded data using the obtained object map. [0010] According to an embodiment of the present invention, a 2D image is encoded and decoded using a depth information image obtained by a depth information camera, thus enhancing encoding efficiency of 2D images. BRIEF DESCRIPTION OF THE DRAWINGS [0011] FIG. 1 is a view illustrating an exemplary actual image and an exemplary depth information map image; [0012] FIG. 2 illustrates a basic structure of a 3D video system and a data form; [0013] FIG. 3 illustrates a Kinect input device, where (a) indicates a Kinect, and (b) indicates depth information processing through the Kinect; [0014] FIG. 4 illustrates an example of a camera system equipped with a depth information camera; [0015] FIG. 5 illustrates an example of a structure of a video encoder in a video system with a depth information camera; [0016] FIG. 6 a illustrates an example of a structure of a video decoder in a video system with a depth information camera; [0017] FIG. 6 b illustrates an encoding/decoding method according to an embodiment of the present invention; [0018] FIG. 6 c illustrates an encoding/decoding method according to another embodiment of the present invention; [0019] FIG. 6 d illustrates an encoding/decoding method according to still another embodiment of the present invention; [0020] FIG. 7 a illustrates an example in which a moving object and an object map for a background are represented in a single image or an example in which they are separated according to an embodiment of the present invention; [0021] FIG. 7 b illustrates an example in which a moving object and an object map for a background are represented in a single image or an example in which they are separated according to another embodiment of the present invention; [0022] FIG. 7 c illustrates object information for separating objects into predetermined units according to an embodiment of the present invention; [0023] FIG. 7 d illustrates object information for separating objects into predetermined units according to another embodiment of the present invention; [0024] FIG. 7 e illustrates object information for separating objects into predetermined units according to still another embodiment of the present invention; [0025] FIG. 7 f illustrates object information for separating objects into predetermined units according to still another embodiment of the present invention; [0026] FIG. 8 illustrates an example of order of a bitstream for transmitting object information on a depth information image in units of images; [0027] FIG. 9 illustrates another example of order of a bitstream for transmitting object information on a depth information image in units of images; [0028] FIG. 10 illustrates an example of order of a bitstream for transmitting object information on a depth information image in units of blocks; [0029] FIG. 11 illustrates another example of order of a bitstream for transmitting object information on a depth information image in units of blocks; [0030] FIG. 12 illustrates an example of a method for performing encoding in units of geometrical blocks; and [0031] FIG. 13 illustrates an example of a result of performing encoding in a geometrical form. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS [0032] What is described below merely exemplifies the principle of the present invention. Thus, one of ordinary skill in the art, although not explicitly described or shown in this disclosure, may implement the principle of the present invention and invent various devices encompassed in the concept or scope of the present invention. It should be appreciated that all the conditional terms enumerated herein and embodiments are clearly intended only for a better understanding of the concept of the present invention, and the present invention is not limited to the particularly described embodiments and statuses. [0033] Further, it should be understood that all the detailed descriptions of particular embodiments, as well as the principles, aspects, and embodiments of the present invention are intended to include structural and functional equivalents thereof. Further, it should be understood that such equivalents encompass all devices invented to the same function regardless of whether they are known equivalents or equivalents to be developed in the future, i.e., regardless of structures. [0034] Accordingly, it should be understood that the block diagrams of the disclosure represent conceptual perspectives of exemplary circuits for specifying the principle of the present invention. Similarly, it should be appreciated that all the flowcharts, status variation diagrams, or pseudo codes may be substantially represented in computer-readable media, and regardless of whether a computer or processor is explicitly shown, represent various processes performed by the computer or processor. [0035] The functions of various devices shown in the drawings including functional blocks represented in processors or their similar concepts may be provided using dedicated hardware or other hardware associated with proper software and capable of executing the software. When provided by a processor, the functions may be provided by a single dedicated processor, a single shared processor or a plurality of individual processors, and some thereof may be shared. [0036] The explicit use of the term “processor,” “control,” or other similar concepts of terms should not be interpreted by exclusively referencing hardware capable of executing software, but understood as implicitly including, but not limited to, digital signal processor (DSP) hardware, ROMs for storing software, RAMs, and nonvolatile memories. Other known hardware may be included as well. [0037] In the claims of the disclosure, the elements represented as means to perform the functions described in the description section are intended to include all methods for performing functions including all types of software including combinations of circuit elements for performing the functions or firmware/micro codes, and are associated with proper circuits for executing the software to perform the functions. It should be understood that the present invention defined by the claims is associated with functions provided by various enumerated means and schemes required by the claims, and thus, any means that may provide the functions belong to the equivalents of what is grasped from the disclosure. [0038] The foregoing objects, features, and advantages will be apparent from the detailed description taken in conjunction with the accompanying drawings, and accordingly, one of ordinary skill in the art may easily practice the technical spirit of the present invention. When determined to make the subject matter of the present invention unclear, the detailed description of known configurations or functions is omitted. [0039] Hereinafter, preferred embodiments of the present invention are described in detail with reference to the drawings. [0040] Depth information is information representing the distance between a camera and an actual object. FIG. 1 shows a normal image and its depth information image. FIG. 1 illustrates an actual image and depth information map image for balloons. (a) denotes the actual image, and (b) denotes the depth information map. [0041] The depth information image is primarily used to generate a 3D virtual view image, and in related studies, JCT-3V (The Joint Collaborative Team on 3D Video Coding Extension Development) of ISO/IEC's MPEG (Moving Picture Experts Group) and ITU-T's VCEG (Video Coding Experts Group) currently proceeds with 3D video standardization. [0042] The 3D video standards include standards regarding advanced data formats and their related technologies that allow for replay of autostereoscopic images as well as stereoscopic images using normal images and their depth information images. [0043] The depth information images used in the 3D video standards are encoded together with normal images and are transmitted to a terminal in bit streams. The terminal decodes the bitstreams and outputs the restored N views of normal images and their (the same number of views of) depth information images. In this case, the N views of depth information images are used to generate an infinite number of virtual view images through a depth image based rendering (DIBR) method. The infinite number of virtual view images generated so are played back in compliance with various stereoscopic display apparatuses to provide users with stereoscopic images. [0044] Microsoft launched the Kinect sensor as a brand-new input device for the XBOX-360 game device. This device recognizes a human operation and connects to a computer system. As shown in FIG. 3 , the device includes an RGB camera and a 3D depth sensor. Further, the Kinect is an imaging device and may generate RGB images and depth information maps up to 640×480 and provide the same to a computer connected thereto. [0045] FIG. 3 illustrates a Kinect input device. (a) Denotes the Kinect, and (b) denotes depth information processing through the Kinect. [0046] The advent of imaging equipment, such as the Kinect, enabled play of 2D and 3D games and execution of imaging services or other various applications at a lower price than that of high-end video systems. Accordingly, depth information camera-equipped video apparatuses are expected to become commonplace. [0047] FIG. 4 illustrates an example of a camera system equipped with a depth information camera. [0048] FIG. 4 illustrates an example of a camera system equipped with a depth information camera. FIG. 4(A) illustrates cameras including one normal image camera and two depth information image cameras, and FIG. 4(B) illustrates cameras including two normal image cameras and one depth information image camera. [0049] As such, future video systems are expected to evolve in the form that they are combined with normal image cameras and depth cameras to basically offer 2D and 3D real life-like image services as well as 2D normal image services. In other words, with such a system, the user may be simultaneously served with 3D real life-like image services and 2D high-definition image services. [0050] In an embodiment, the user using a 2D high-definition service may turn into a 3D real life-like service. In contrast, the user using a 3D real life-like service may turn into a 2D high-definition service (the smart device basically equipped with 2D/3D switching technology and devices). [0051] A video system basically equipped with a normal camera and a depth camera may not only use depth image through a 3D video codec but also use 3D depth information through a 2D video codec. [0052] The algorithms designed for current 2D video codecs fail to reflect use of depth information. However, the encoding method proposed herein is based on the idea that future video systems may be utilized to code 2D high-definition images as well as 3D images using depth information images obtained through depth information cameras already equipped therein. [0053] A camera system with a depth information camera may code normal images using legacy video codecs. Here, examples of the legacy video codecs include MPEG-1, MPEG-2, MPEG-4, H.261, H.262, H.263, H.264/AVC, MVC, SVC, HEVC, SHVC, 3D-AVC, 3D-HEVC, VC-1, VC-2, and VC-3 or other various codecs. Embodiment 1 Image Encoding Using Depth Information [0054] The basic idea of the present invention is to utilize depth information images obtained with a depth information camera to code 2D normal images in order to maximize encoding efficiency for normal 2D images. [0055] In an embodiment, in case objects of a normal image are separated using a depth information image, the encoding efficiency for the normal image may be significantly increased. Here, the objects mean a number of objects and may include a background image. For a block-based encoding codec, several objects may be present in a block, and different encoding methods may apply to objects, respectively, based on depth information images. In this case, information for separating the objects of a 2D normal image (for example, flag information: not depth image pixel information) may be included in a bitstream that transmits encoded 2D images. [0056] FIG. 5 illustrates an example of a structure of a video encoder in a video system with a depth information camera. In the video encoder shown in FIG. 5 , a 2D normal image is encoded using a depth information image. In this case, the depth information image is transformed into an object map form and is used to code the 2D normal image. [0057] To transform the depth information image into the object map form, various methods such as a threshold value scheme, an edge detection scheme, an area growth method, and a scheme using texture feature values may come in use. [0058] In an embodiment, the threshold value scheme, a method of dividing an image with a threshold, is a method in which a histogram is created for a given image, a threshold is determined, and the image is separated into an object and a background. This scheme may present good performance when offering one threshold value, but may not when determining multiple threshold values. [0059] In another embodiment, edge detection may refer to discovery of pixels with discontinuous gray levels in an image. This method comes in two types: a sequential-type method that an earlier calculated result influences a subsequent calculation, and a parallel-type method that whether a pixel has an edge is affected only by its neighbor pixel to allow for parallel calculation. There are a great number of operators in the edge detection scheme, among which a most frequently used operator is an edge operator mainly adopting a first-order differentiated Gaussian function. [0060] In another embodiment, the area growth scheme is a method in which the similarity between pixels is measured, and the area is expanded and split. In general, the area growth scheme may be inefficient in case there are severe variations in gray levels of pixels in an object when setting an absolute threshold and measuring the similarity between neighboring pixels and the border between the object and background is unclear. [0061] Still another embodiment is a method using texture feature values for quantifying discontinuous variations in pixel values of an image. Splitting using only texture features benefits in light of speed, but this method may be inefficient in splitting if different features are gathered in one area or the border between the features is unclear. [0062] Such object map-related information is included in a bitstream and transmitted. Depth information is used for encoding 2D normal images, but not for encoding 3D images. Therefore, rather than depth information images themselves being encoded and transmitted in bitstreams, only basic information (not depth information images themselves) for utilizing the object map on the end of decoder may be included in bitstreams and transmitted. [0063] FIG. 6 a illustrates an example of a structure of a video decoder in a video system with a depth information camera. The video decoder receives a bitstream, demultiplexes the bitstream, and parses the normal image information and object map information. [0064] In this case, the object map information may be used to parse the normal image information, and reversely, the parsed normal image information may be used to create an object map. This may apply in various manners. [0065] 1) In an embodiment, a normal image information parsing unit and an object map information parsing unit are parsed independently from each other. [0066] 2) In another embodiment, normal image information is parsed using the parsed object map information. [0067] 3) In still another embodiment, object map information is parsed using the parsed normal image information. [0068] Besides, the parsing unit may apply in various methods. [0069] The parsed object map information is input to a normal image information decoder and is used to decode the 2D normal image. Finally, the normal image information decoder outputs the 2D normal image restored by performing decoding using the object map information. [0070] In this case, the decoding using the object map information is performed on a per-object basis. In an existing encoding scheme, the overall frame (image or picture) means one object as shown in FIG. 6 b , while in the per-object encoding/decoding, any type of object is meant to be encoded/decoded as shown in FIG. 6 c . In this case, video object (VO) may be a partial area of a video scene and may be present in any shaped area, and may exist for a time. A VO at a particular time is denoted a VOP (Video Object Plane). [0071] FIG. 6 b illustrates an example of a per-frame encoding/decoding method, and FIG. 6 c illustrates an example of a per-object encoding/decoding method. [0072] FIG. 6 b shows one VO consisting of three rectangular VOPs. In contrast, FIG. 6 c shows one VO consisting of three VOPs each having an irregular shape. Each VOP may be present in a frame, and may be independently subjected to object-based encoding. [0073] FIG. 6 d illustrates an embodiment in which one frame is separated into three objects in per-object encoding. In this case, each object (V 01 , V 02 , and V 03 ) is independently encoded/decoded. Each independent object may be encoded/decoded with a different picture quality and temporal resolution to reflect its importance to the final image. Objects obtained from several sources may be combined in one image. [0074] Meanwhile, in case there are a plurality of object maps, a definition for the case where separation is made into a background object and an object for a moving thing may be added. Further, in an embodiment, a definition for the case where separation is made into a background object, an object for a moving thing, and an object for text, may be added as well. [0075] In case no object map information is transferred from the encoder to the decoder, an object map may be created using the information already decoded by the decoder (normal image or other information). The object map created so by the decoder may be used to decode a next normal image. However, creation of an object map in the decoder may increase the complexity of the decoder. [0076] Meanwhile, the decoder may decode normal images using an object map or may decode normal images even without using an object map. Information on whether to use an object map may be included in a bitstream, and such information may be contained in VPS, SPS, PPS, or Slice Header. [0077] The decoder may generate a depth information image using the object map information and use the generated depth information image for a 3D service. An embodiment of a method for generating a depth information image using object map information is to generate a depth information image by allocating different depth information values to objects in an object map. In this case, the allocation of the depth information values may depend on the characteristics of objects. That is, depending on the characteristics of objects, higher or lower depth information values may be allocated. Embodiment 2 Method for Configuring Bitstream [0078] Upon using a depth information image to code a 2D normal image, the depth information image may be transformed into an object map form and may be used. The object map may come in the case in which a moving object and an object map for a background are represented in a single image or the case in which they are separated. In an embodiment, FIG. 7 a illustrates the case where a moving object and an object map for a background both are represented in one image. In another embodiment, FIG. 7 b illustrates the case where a moving object and an object map for a background are represented in different images, respectively. [0079] The object map may be calculated or separated in units of images, in units of arbitrary shapes, in units of blocks, or in units of any areas. [0080] First, in case an object map for a depth information image is transmitted in units of images, information for differentiating the objects through labeling may be transmitted. [0081] FIG. 7 c illustrates an embodiment of a per-image object map. As shown in FIG. 7 c , one image may be separated into four objects. Among them, object 1 is separated from the other objects and is independently present. Objects 2 and 3 overlap each other. Object 4 represents the background. [0082] Second, in case an object map for a depth information image is transmitted in units of arbitrary shapes, information for differentiating the labeled objects may be transmitted. [0083] FIG. 7 d illustrates an embodiment for information for differentiating objects in units of arbitrary shapes. [0084] Third, in case an object map for a depth information image is transmitted in units of blocks, information for differentiating the objects labeled only in the block area may be transmitted. [0085] FIG. 7 e illustrates an embodiment for information for differentiating objects in units of blocks. As shown in FIG. 7 e , an object map for the area where objects are present in units of blocks may be transmitted. [0086] Fourth, in case an object map for a depth information image is transmitted in units of any areas, information for differentiating the objects labeled only for any area where there are moving objects may be transmitted. [0087] FIG. 7 f illustrates an embodiment for information for differentiating objects in units of any areas. As shown in FIG. 7 c , an object map for an area where objects are present (for example, area including object 2 and object 3 ) may be transmitted. [0088] Here, the information for differentiating objects may be represented in labeled information and transmitted, or information for differentiating objects by other methods may be transmitted. Various changes may be made to the method for representing the object map. [0089] FIG. 8 illustrates an example of order of a bitstream for transmitting object information on a depth information image in units of images. The header information may include information on parameters necessary to decode normal image information and depth configuration information. The depth configuration information may include information for differentiating objects through labeling (or information for differentiating objects by other methods). The depth configuration information may be encoded/decoded by applying an encoding method for normal images or applying shape encoding of MPEG-4 Part 2 Visual (ISO/IEC 14496-2). Such depth configuration information may be used to decode normal images. The normal image information may contain information for restoring normal images (e.g., encoding mode information, intra-screen direction information, motion information, residual signal information). [0090] FIG. 9 illustrates another example of order of a bitstream for transmitting object information on a depth information image in units of images. The header information of FIG. 8 may include information on parameters necessary to decode object information of depth information images and 2D normal images. The object information of depth information images includes information for differentiating objects through labeling (or information for differentiating objects by other methods). Further, the object information of depth information images may include information for differentiating objects for depth information images in units of any areas or in units of arbitrary shapes. The object information of depth information images may be encoded/decoded by applying an encoding method for normal images or applying shape encoding of MPEG-4 Part 2 Visual (ISO/IEC 14496-2). The object information of depth information images may be used to decoder the header information of 2D normal images or used to decode information for restoring 2D normal images (e.g., encoding mode information, intra-screen direction information, motion information, or residual signal information). The header information of 2D normal images may contain information on parameters necessary to decode 2D normal images. The encoded bitstream of a 2D normal image may contain information for restoring the 2D normal image (e.g., encoding mode information, intra-screen direction information, motion information, residual signal information). [0091] FIG. 10 illustrates an example of order of a bitstream for transmitting depth configuration information in units of blocks. The header information of FIG. 10 may include information on parameters necessary to decode depth configuration information and 2D normal images. The depth configuration information may include information for differentiating objects through labeling in units of blocks (or information for differentiating objects by other methods). The depth configuration information may be encoded/decoded by applying an encoding method for normal images or applying shape encoding of MPEG-4 Part 2 Visual (ISO/IEC 14496-2). Such depth configuration information may be used to decode normal image blocks. The normal image information may contain information for restoring blocks of 2D normal images (e.g., encoding mode information, intra-screen direction information, motion information, residual signal information). [0092] FIG. 11 illustrates still another example of order of a bitstream for transmitting object information on a depth information image in units of blocks. The integrated header information of FIG. 11 may include information on parameters necessary to decode object information of depth information blocks and 2D normal images. The object information of depth information blocks includes information for differentiating objects through labeling in units of blocks (or information for differentiating objects by other methods). The object information of depth information blocks may be encoded/decoded by applying an encoding method for normal images or applying shape encoding of MPEG-4 Part 2 Visual (ISO/IEC 14496-2). The object information of depth information blocks may be used to decoder the header information of images or used to decode information for restoring normal images (e.g., encoding mode information, intra-screen direction information, motion information, or residual signal information). The prediction information of images may contain prediction information necessary for restoring 2D normal images (e.g., encoding mode information, intra-screen direction information, or motion information). Residual signal information of normal images may contain residual signal information for 2D normal images. Embodiment 3 Signaling Method [0093] The above-proposed method differs from the legacy normal image encoding scheme in light of using depth configuration information to code normal images based on objects. Accordingly, a need exists for different signaling methods between images applied with the proposed method and images applied with the legacy method. [0094] Images applied with the proposed method may be newly defined in nal_unit_type and may be signaled. A NAL (Network Abstract Layer) contains header information for differentiating VCLs (Video Coding Layers) including a bitstream of an encoded image and Non-VCLs including information for images necessary for encoding and decoding the images (for example, width and height of images). There may be various types of VCLs and Non-VCLs and the types may be differentiated by nal_unit_type. Accordingly, the proposed signaling method may make distinctions from the bitstream of normal images encoded by the legacy method by newly defining nal_unit_type for bitstreams obtained by encoding normal images based on depth configuration information. [0000] TABLE 1 nal_unit_type Name of nal_unit_type Content of NAL unit and RBSP syntax structure NAL unit type class 01 TRAIL_NTRAIL_R Coded slice segment of a non-TSA, non-STSA VCL trailing pictureslice_segment_layer_rbsp( ) 23 TSA_NTSA_R Coded slice segment of a TSA VCL pictureslice_segment_layer_rbsp( ) 45 STSA_NSTSA_R Coded slice segment of an STSA VCL pictureslice_layer_rbsp( ) 67 RADL_NRADL_R Coded slice segment of a RADL VCL pictureslice_layer_rbsp( ) 89 RASL_NRASL_R Coded slice segment of a RASL VCL pictureslice_layer_rbsp( ) 101214 RSV_VCL_N10RSV_VCL — Reserved non-IRAP sub-layer non-reference VCL VCL N12RSV_VCL_N14 NAL unit types 111315 RSV_VCL_R11RSV_VCL — Reserved non-IRAP sub-layer reference VCL VCL R13RSV_VCL_R15 NAL unit types 161718 BLA_W_LPBLA_W — Coded slice segment of a BLA VCL RADLBLA_N_LP pictureslice_segment_layer_rbsp( ) 1920 IDR_W_RADLIDR_N — Coded slice segment of an IDR VCL LP pictureslice_segment_layer_rbsp( ) 21 CRA_NUT Coded slice segment of a CRA VCL pictureslice_segment_layer_rbsp( ) 2223 RSV_IRAP_VCL22RSV — Reserved IRAP VCL NAL unit types VCL IRAP_VCL23 24 . . . 31 RSV_VCL24 . . . RSV — Reserved non-IRAP VCL NAL unit types VCL VCL31 32 VPS_NUT Video parameter setvideo_parameter_set_rbsp( ) non-VCL 33 SPS_NUT Sequence parameter setseq_parameter_set_rbsp( ) non-VCL 34 PPS_NUT Picture parameter setpic_parameter_set_rbsp( ) non-VCL 35 AUD_NUT Access unit delimiteraccess_unit_delimiter_rbsp( ) non-VCL 36 EOS_NUT End of sequenceend_of_seq_rbsp( ) non-VCL 37 EOB_NUT End of bitstreamend_of_bitstream_rbsp( ) non-VCL 38 FD_NUT Filler datafiller_data_rbsp( ) non-VCL 3940 PREFIX_SEI_NUTSUFFIX — Supplemental enhancement informationsei_rbsp( ) non-VCL SEI_NUT 41 OBJECT_NUT Object_dataObject_data_rbsp( ) VCL (or non-VCL) 42 . . . 47 RSV_NVCL41 . . . RSV — Reserved non-VCL NVCL47 48 . . . 63 UNSPEC48 . . . UNSPEC63 Unspecified non-VCL [0095] Table 1 represents an example of the case where per-object encoding type (OBJECT_NUT) is added to HEVC's NAL type. [0096] In Table 1, In the case of OBJECT_NUT NAL type, it may represent that a corresponding bitstream may be interpreted and decoded with an object map. The depth configuration information (or depth information image, block or any area of object information) may be encoded/decoded by applying an encoding method for normal images or applying shape encoding of MPEG-4 Part 2 Visual (ISO/IEC 14496-2). Accordingly, upon application of the encoding method for normal images, data for normal images is, as is, used for Object_data_rbsp( ). Further, upon application of Shape Coding of MPEG-4 Part 2 Visual (ISO/IEC, 14496-2), data for Shape Coding of MPEG-4 Part 2 Visual (ISO/IEC 14496-2) may be used, as is, for Object_data_rbsp( ). [0097] In case where a normal image is encoded in a geometrical form of block [0098] The current video encoding codec codes images in units of rectangular blocks. However, images may be encoded in units of geometrical forms of blocks in the future to enhance encoding efficiency and subjective image quality. FIG. 12 illustrates an example of such a geometrical form. Referring to FIG. 12 , a rectangular block is divided into geometrical blocks respectively including a white portion and a black portion with respect to a diagonal line. The geometrical blocks may be subjected to prediction independently from each other. [0099] FIG. 13 illustrates an example in which a block is split into geometrical forms in an image encoded in the geometrical form. As shown in FIG. 13 , each block may be separated into geometrical forms as shown in FIG. 12 , so that each block may be subjected to prediction encoding independently from another. [0100] FIG. 12 illustrates an example of a method for performing encoding in units of geometrical forms of blocks, and FIG. 13 illustrates an example of a result of performing encoding in the geometrical form. [0101] When encoded in the geometrical form, normal images may be object-split as well. Simultaneous use of an object map using depth information images and split information on normal images may maximize the efficiency of encoding 2D normal images. The method for creating an object map using split information on normal images is shown in FIG. 6 and has been already described. [0102] The above-described methods according to the present invention may be prepared in a computer executable program that may be stored in a computer readable recording medium, examples of which include a ROM, a RAM, a CD-ROM, a magnetic tape, a floppy disc, or an optical data storage device, or may be implemented in the form of a carrier wave (for example, transmission through the Internet). [0103] The computer readable recording medium may be distributed in computer systems connected over a network, and computer readable codes may be stored and executed in a distributive way. The functional programs, codes, or code segments for implementing the above-described methods may be easily inferred by programmers in the art to which the present invention pertains. [0104] Although the present invention has been shown and described in connection with preferred embodiments thereof, the present invention is not limited thereto, and various changes may be made thereto without departing from the scope of the present invention defined in the following claims, and such changes should not be individually construed from the technical spirit or scope of the present invention.

A method for decoding an image, according to one embodiment of the present invention, comprises the steps of: receiving encoded data; extracting depth information from the encoded data; decoding the encoded data by using the depth information; and obtaining a normal two-dimensional image from the decoded data by using the depth information.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention concerns an ultra miniature integrated cardiac pacemaker and distributed cardiac pacing system. The invention provides an ultra miniature integrated cardiac pacemaker and distributed cardiac pacing system that allows pacing of the heart without the need for conventional lead wires that connect the electrodes and the main body of the pacemaker, and allows implantation by catheter manipulation without incising the chest wall, which avoids imposing an extra burden on the user. In this invention, “ultra miniature” refers to the minute size of the pacemaker to the extent that it can be attached to the tip of a catheter. 2. Description of Related Art A cardiac pacemaker is a device that controls the rhythm of the heart by delivering electrical impulses to the heart, and is indicated for use in patients with symptoms of bradyarrhythmia. A conventional cardiac pacemaker includes the main body of the cardiac pacemaker (generator), lead wires, and electrodes that transmit a stimulating pulse to the myocardium. The main body of the cardiac pacemaker and the electrodes are connected by lead wires. However, conventional pacemakers have the following problems. Since the main body of the cardiac pacemaker and the electrodes are connected by lead wires, cases of breaking of the lead wires have occurred. Breakage of the lead wires results in defective pacing. In addition, there have been also cases of venous obstruction by the lead wires. Moreover, during the early stages after implantation of the cardiac pacemaker, a shift in position of the electrodes may cause defective pacing. When a shift in position of the electrodes occurs, a second operation has to be performed, which adds extra strain for the patient. Furthermore, if there is a defective hermetic sealing structure at the junction between the cardiac pacemaker main body and the lead wires, this may lead to defective pacemaker movement. Problems with electrical safety have also occurred. In the Unexamined Japanese Patent Publication Heisei No. 5-245215, a cardiac pacemaker is described in which the signals for cardiac stimulation are delivered from the cardiac pacemaker main body to the stimulation electrodes by wireless transmission, thus eliminating the lead wires between the cardiac pacemaker main body and the electrodes. However, even for this type of cardiac pacemaker, surgical implantation of the pacemaker cannot be avoided, and there have been cases in which skin necrosis occurred at the cardiac pacemaker implantation site. Also, in the above-mentioned cardiac pacemaker, although wireless communication is conducted between the pacemaker main body and the electrodes, there is no communication between the electrodes. Synchrony between the multiple electrodes being used is controlled by the pacemaker main body. The present invention was developed in order to solve the above problems, and to provide an ultra miniature integrated cardiac pacemaker and distributed cardiac pacing system with the following features: the generator function of electric stimulus by the pacemaker main body is integrated with the electrodes, thus allowing pacing of the heart without the need for conventional lead wires connecting the electrodes and pacemaker main body. By integrating the control unit of the pacemaker main body and the electrodes, there is no need to implant the pacemaker main body, which avoids imposing an extra burden on the user. SUMMARY OF THE INVENTION The ultra miniature integrated cardiac pacemaker of the present invention requires no chest incision, and is implanted in the heart by attaching it to the tip of a catheter and extracting the catheter after implanting. In one embodiment, the pacemaker includes a control unit that outputs control signals, a heart stimulating means that responds to the control signal and electrically stimulates the heart tissue, an electrocardiographic information detecting means that detects the electrocardiographic information and outputs it to the control unit, and a power unit that supplies the driving power. The control unit outputs the control signals based on electrocardiographic information. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as an electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. In another embodiment of the present invention, an ultra miniature integrated cardiac pacemaker includes a control unit that outputs control signals, a heart stimulating means that responds to the control signal and electrically stimulates the heart tissue, an electrocardiographic information detecting means that detects the electrocardiographic information and outputs it to the control unit, a transmitting means that modulates the electrocardiographic information and control signals to be sent outside, and a power unit that supplies the driving power. The control unit outputs the control signals based on electrocardiographic information. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as an electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. In a third embodiment, an ultra miniature integrated cardiac pacemaker includes a control unit that outputs control signals, a heart stimulating means that responds to the control signal and electrically stimulates the heart tissue, an electrocardiographic information detecting means that detects the electrocardiographic information and outputs it to the control unit, a receiving means that receives and demodulates the information sent from outside, and a power unit that supplies the driving power. It is designed such that the information sent from outside is input into the control unit. The control unit outputs control signals based on information sent from outside and/or electrocardiographic information. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as an electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. In yet another embodiment, an ultra miniature integrated cardiac pacemaker includes a control unit that outputs control signals, a heart stimulating means that responds to the control signal and electrically stimulates the heart tissue, an electrocardiographic information detecting means that detects the electrocardiographic information and outputs it to the control unit, a transmitting means that modulates the electrocardiographic information and control signals to be sent outside, a receiving means that receives and demodulates the information sent from outside, and a power unit that supplies the driving current. It is designed such that the information sent from outside is input into the control unit. The control unit outputs control signals based on information sent from outside and/or electrocardiographic information. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. Another embodiment discloses a cardiac pacing system including an ultra miniature integrated cardiac pacemaker placed in the atrial myocardium. The ultra miniature integrated cardiac pacemaker is equipped with a control unit that outputs control signals, a power unit that supplies the driving power, a heart stimulating means that responds to the control signals and electrically stimulates the atrial myocardium, and an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac P wave information. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as an electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. The control unit is equipped with a stimulation timing determining means that decides the timing of stimulation to generate control signals, and a stimulation timing changing means that changes the timing of stimulation to generate control signals. It is characterized by the ability to change the timing of stimulation to generate the control signal, in case intracardiac P wave information is detected within a preset time interval. Yet another embodiment concerns a distributed cardiac pacing system including an electrocardiographic information detecting device placed in the atrial myocardium and an ultra miniature integrated cardiac pacemaker placed in the ventricular myocardium. The electrocardiographic information detecting device is equipped with an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac P wave information, a transmitting means that modulates the electrocardiographic information detected and sends the information to the ultra miniature integrated cardiac pacemaker, and a power unit that supplies the driving current. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as an electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. The ultra miniature integrated cardiac pacemaker is equipped with a receiving means that receives and demodulates the electrocardiographic information sent from the electrocardiographic information detection device, a control unit that outputs control signals, a power unit that supplies the driving power, and a heart stimulating means that responds to the control signal and electrically stimulates the ventricular myocardium. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as an electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. The control unit is equipped with a stimulation timing determining means that decides the timing of stimulation to generate the control signals, and a stimulation timing changing means that changes the timing of stimulation to generate the control signals. It is characterized by a mechanism to generate control signals when intracardiac QRS complex information is not detected within a given time after the detection of intracardiac P wave, and suppress the control signals when QRS complex information is detected within a given time after the detection of intracardiac P wave information. Another embodiment discloses a distributed cardiac pacing system including a first ultra miniature integrated cardiac pacemaker placed in the atrial myocardium and a second ultra miniature integrated cardiac pacemaker placed in the ventricular myocardium. The first ultra miniature integrated cardiac pacemaker is equipped with a control unit that outputs control signals, a power unit that supplies the driving power, a heart stimulating means that responds to the control signal and electrically stimulates the atrial myocardium, an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac P wave information, a transmitting means that modulates the electrocardiographic information and sends the information to the second ultra miniature integrated cardiac pacemaker, and a receiving means that receives and demodulates the electrocardiographic information sent from the second ultra miniature integrated cardiac pacemaker. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as an electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. The electrocardiographic information sent from the second ultra miniature integrated cardiac pacemaker is input into the control unit; and the control unit is equipped with a stimulation timing determining means that decides the timing of stimulation to generate the control signals, and a stimulation timing changing means that changes the timing of stimulation to generate the control signals. The second ultra miniature integrated cardiac pacemaker is equipped with a control unit that outputs control signals, a power unit that supplies the driving power, a heart stimulating means that responds to the control signal and electrically stimulates the ventricular myocardium, an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac QRS complex information, a transmitting means that modulates the electrocardiographic information and sends the information to the first ultra miniature integrated cardiac pacemaker, and a receiving means that receives and demodulates the electrocardiographic information sent by the first ultra miniature integrated cardiac pacemaker. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. The electrocardiographic information sent from the first ultra miniature integrated cardiac pacemaker is input into the control unit; and the control unit is equipped with a stimulation timing determining means that decides the timing of stimulation to generate the control signal, and a stimulation timing changing means that changes the timing of stimulation to generate the control signal. The control unit of the first ultra miniature integrated cardiac pacemaker generates the control signal when intracardiac P wave information is not detected within a given time interval, and suppresses the generation of control signals when intracardiac P wave information is detected within a given time. The control unit of the second ultra miniature integrated cardiac pacemaker generates control signals when intracardiac QRS complex information is not detected within a given time after detection of intracardiac P wave information, and suppresses the generation of control signals when intracardiac QRS complex information is detected within a given time after detection of intracardiac P wave information. The system is also characterized by the following mechanism: if the second ultra miniature integrated cardiac pacemaker detects intracardiac QRS complex information due to spontaneous ventricular contraction, the control unit of the first ultra miniature integrated cardiac pacemaker suppresses the detection of intracardiac P wave information for a given time interval. Another embodiment discloses a distributed cardiac pacing system including an electrocardiographic information detection device placed in the atrial myocardium and multiple ultra miniature integrated cardiac pacemakers placed in the ventricular myocardium. The electrocardiographic information detection device is equipped with an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac P wave information, a transmitting means that modulates the detected electrocardiographic information and sends the information to the ultra miniature integrated cardiac pacemakers, and a power unit that supplies the driving power. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. The ultra miniature integrated cardiac pacemakers are equipped with a control unit that outputs control signals, a power unit that supplies the driving power, a heart stimulating means that responds to the control signals and electrically stimulates the ventricular muscle, an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac QRS complex information, a transmitting means that modulates the electrocardiographic information and sends the information to other ultra miniature integrated cardiac pacemakers, and a receiving means that receives and demodulates the electrocardiographic information sent from other ultra miniature integrated cardiac pacemakers. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as an electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. The electrocardiographic information sent from other ultra miniature integrated cardiac pacemakers is input into the control unit; and the control unit is equipped with a stimulation timing determining means that decides the timing of stimulation to generate the control signals, and a stimulation timing changing means that changes the timing of stimulation to generate the control signals. The system is characterized by the following mechanism: when individual ultra miniature integrated cardiac pacemakers do not detect intracardiac QRS complex information within the respective preset times after detection of intracardiac P wave information, the control units of the ultra miniature integrated cardiac pacemakers generate control signals; whereas when QRS complex information is detected within given time intervals after detection of intracardiac P wave information, the control units generate control signals synchronous to the earliest timing at which the intracardiac QRS complex information is first detected. Yet another embodiment discloses a distributed cardiac pacing system including a first ultra miniature integrated cardiac pacemaker placed in the atrial myocardium and multiple second ultra miniature integrated cardiac pacemakers placed in the ventricular myocardium. The first ultra miniature integrated cardiac pacemaker is equipped with a control unit that outputs control signals, a power unit that supplies the driving power, a heart stimulating means that responds to the control signals and electrically stimulates the atrial myocardium, an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac P wave information, a transmitting means that modulates the electrocardiographic information and sends the information to multiple second ultra miniature cardiac pacemakers, and a receiving means that receives and demodulates the electrocardiographic information sent by the multiple second ultra miniature integrated cardiac pacemakers. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. The electrocardiographic information sent from the multiple second ultra miniature integrated cardiac pacemakers are input into the control unit; and the control unit is equipped with a stimulation timing determining means that decides the timing of stimulation to generate the control signals, and a stimulation timing changing means that changes the timing of stimulation to generate the control signals. The multiple second ultra miniature integrated cardiac pacemakers are each equipped with a control unit that outputs control signals, a power unit that supplies the driving current, a heart stimulating means that responds to the control signal and electrically stimulates the ventricular myocardium, an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac QRS complexes, a transmitting means that modulates the electrocardiographic information and sends the information to the first and other second ultra miniature cardiac pacemakers, and a receiving means that receives and demodulates the electrocardiographic information sent from the first and other second ultra miniature integrated cardiac pacemakers. The power unit is preferably a biological fuel cell that extracts electrons from oxidative reactions of biological fuels. The biological fuel cell is composed of an anode electrode and a cathode electrode. The anode electrode is coated with immobilized oxidative enzymes for biological fuels and mediators. The biological fuel cell uses blood and/or body fluid as an electrolyte solution and utilizes biological fuels and oxygen in blood and/or body fluid. The electrocardiographic information sent from the first and other second ultra miniature integrated cardiac pacemakers is input into the control unit; and the control unit is equipped with a stimulation timing determining means that decides the timing of stimulation to generate the control signals, and a stimulation timing changing means that changes the timing of stimulation to generate the control signals. The control unit of the first ultra miniature integrated cardiac pacemaker generates control signals when intracardiac P wave information is not detected within a given time interval, and suppresses the generation of control signal when intracardiac P wave information is detected within a given time. The control units of the second ultra miniature integrated cardiac pacemakers generate control signals when intracardiac QRS complex information is not detected by individual ultra miniature integrated cardiac pacemakers within the respective preset time intervals after the detection of intracardiac P wave information; whereas if intracardiac QRS complex information is detected within the given time intervals after the detection of intracardiac P wave information, the control units generate control signals synchronous to the earliest timing at which intracardiac QRS complex information is detected. The system is also characterized by the following mechanism: when one of the multiple second ultra miniature integrated cardiac pacemakers detects intracardiac QRS complex information due to spontaneous ventricular contraction, the control unit of the first ultra miniature integrated cardiac pacemaker suppresses the detection of intracardiac P wave information for a given interval. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a simplified block diagram of an ultra miniature integrated cardiac pacemaker in accordance with the first embodiment. FIG. 2 is a simplified block diagram of an ultra miniature integrated cardiac pacemaker in accordance with the first embodiment. FIG. 3 is a simplified block diagram of an ultra miniature integrated cardiac pacemaker in accordance with the second embodiment. FIG. 4 is a simplified block diagram of an ultra miniature integrated cardiac pacemaker in accordance with the third embodiment. FIG. 5 is a simplified block diagram of an ultra miniature integrated cardiac pacemaker in accordance with the fourth embodiment. FIG. 6 is a schematic diagram illustrating a first application of the ultra miniature integrated cardiac pacemaker in accordance with the present invention (the first distributed cardiac pacing system). FIG. 7 is a schematic diagram illustrating a second application of the ultra miniature integrated cardiac pacemaker in accordance with the present invention (the second distributed cardiac pacing system). FIG. 8 is a block diagram illustrating an outline of the electrocardiographic information detection device. FIG. 9 is a schematic diagram illustrating a third application of the ultra miniature integrated cardiac pacemaker in accordance with the present invention (the third distributed cardiac pacing system). FIG. 10 is a schematic diagram illustrating a fourth application of the ultra miniature integrated cardiac pacemaker in accordance with the present invention (the fourth distributed cardiac pacing system). DETAILED DESCRIPTION OF THE INVENTION The present invention is described in detail below while referring to the figures. FIG. 1 is a simplified block diagram of an ultra miniature integrated cardiac pacemaker ( 100 ) in accordance with a first embodiment of this invention. The ultra miniature integrated cardiac pacemaker ( 100 ) in this embodiment is composed of a control unit ( 2 ) that outputs control signals, a heart stimulating means ( 3 ) that responds to the control signals and electrically stimulates the heart tissue, an electrocardiographic information detecting means ( 5 ) that detects the electrocardiographic information and outputs it to the control unit ( 2 ), a transmitting means ( 10 ) that modulates the control signals output from the control unit ( 2 ) and/or electrocardiographic information detected by the electrocardiographic information detecting means ( 5 ) and sends the information outside, a receiving means ( 9 ) that receives and demodulates the information sent from outside, and a power unit ( 4 ) that supplies the driving current. The heart stimulating means ( 3 ) responds to the control signal output from the control unit ( 2 ) and electrically stimulates the heart tissue. The heart stimulating means ( 3 ) as shown in the diagram is able to stimulate the heart tissue. The heart stimulating means ( 3 ) includes a stimulating unit ( 31 ) that responds to the control signals output from the control unit ( 2 ) and outputs heart stimulating pulses to stimulate the heart tissue, and two heart stimulating electrodes ( 32 ) that stimulate the heart tissue in response to the output pulses. The electrocardiographic information detecting means ( 5 ) detects the electrocardiographic information at the site where the ultra miniature integrated cardiac pacemaker is placed. The detected electrocardiographic information is output to the control unit ( 2 ). The electrocardiographic information detected by the electrocardiographic information detecting means ( 5 ) includes P wave information, QRS complex information, T wave information, or Q-T time, A-H time, H-V time (where A is atrial potential, H is His bundle potential, and V is ventricular potential). The electrocardiographic information detecting means ( 5 ) as shown in the diagram is composed of two electrocardiographic information recording electrodes ( 53 ) that detect the applied site electrocardiographic information at the placement site, an amplifying unit ( 51 ) that amplifies the electrocardiogram, and an A/D conversion ( 52 ) unit that converts the detected electrocardiographic information into digital signals. The electrocardiographic information detecting means ( 5 ) is designed such that the converted electrocardiographic information is output to the control unit ( 2 ). The transmitting means ( 10 ) is composed of a modulating unit ( 11 ) that inputs and modulates the control signals output from the control unit ( 2 ) and/or electrocardiographic information, and a transmitting unit ( 12 ) that sends the modulated control signals to the outside via carrier waves; by which the modulated control signals are sent to the outside (such as to other ultra miniature integrated cardiac pacemakers, not shown in the diagram). By transmitting control signals and electrocardiographic information via carrier waves to outside sites such as other cardiac pacemakers, it is possible, for example, to activate two or more cardiac pacemakers synchronously. Moreover, since carrier waves are used for transmission, there is no need for lead wires, and this method avoids imposing an extra burden on the user. The receiving means ( 9 ) is composed of a receiving unit ( 91 ) that receives information transmitted from the outside via carrier waves, and a demodulating unit ( 92 ) that demodulates the information received. It is designed such that the demodulated information is input into the control unit ( 2 ). Based on this information and/or electrocardiographic information, control signals are generated in the control unit ( 2 ) and output to the heart stimulating means ( 3 ). The information transmitted from the outside includes electrocardiographic information and control signals sent from other cardiac pacemakers. By equipping the receiving means ( 9 ) that receives information from, for instance, other cardiac pacemakers, it is possible to activate the cardiac pacemaker synchronously with other cardiac pacemakers. Moreover, since there is no need for lead wires, this method avoids imposing extra burden on the user. Possible modes of communication between pacemakers executed by the transmitting means ( 10 ) and receiving means ( 9 ) include, but are not limited to, spread spectrum communication using radio waves or ultrasound waves, and ultra wide band communication. There is no restriction on the mode of communication. Any method can be used as long as it provides reliable communication between pacemakers. The power unit ( 4 ) is designed to supply a power source necessary to drive the ultra miniature integrated cardiac pacemaker. As a power unit ( 4 ), in general, it is possible to use a lithium battery or fuel cells. However, in the conventional cardiac pacemakers, the power unit that supplies the electrical source is the largest component. To ultra-miniaturize the cardiac pacemaker, it is necessary to miniaturize the power unit. For the ultra miniature integrated cardiac pacemaker ( 100 ) according to the present invention, a biological fuel cell is preferably used as the power unit ( 4 ). If a biological fuel cell is used as the power unit, biological fuels such as glucose and oxygen, which are necessary to drive the biological fuel cell, are available in constant supply inside the body. The volume of the power unit ( 4 ) depends only on the size of the electrodes, making it possible to miniaturize the volume of the power unit ( 4 ). Moreover, metabolites and intermediate metabolic products of sugars (e.g., glucose), such as water, carbon dioxide and gluconolactone, are safe for the human body and they are rapidly removed from the vicinity of the electrodes by blood flow. Biological fuel cells that use enzymes as catalysts can operate under mild conditions such as neutral pH and room temperature. One example of a biological fuel cell used in this invention is the well-known conventional biological fuel cell that extracts electrons from oxidative reactions of biological fuels. This biological fuel cell uses sugars (such as glucose) and oxygen, both supplied by the body, as fuels, and utilizes enzymes as biological catalysts. An example of the composition of the preferable biological fuel cell ( 40 ) for this invention will be explained by referring to the diagram. FIG. 2 is a schematic diagram illustrating the simplified structure of the biological fuel cell ( 40 ) as the power unit in the ultra miniature integrated cardiac pacemaker ( 100 ) of the first embodiment. The biological fuel cell ( 40 ) is composed of an anode ( 41 ) and a cathode ( 42 ). This biological fuel cell utilizes blood or body fluid as the electrolyte solution, and also utilizes sugars and oxygen in blood and body fluid as biological fuels. Therefore, the anode electrode ( 41 a ) and the cathode electrode ( 42 a ) are positioned so as to be in contact with blood or body fluid. In FIG. 2 , the anode electrode ( 41 a ) and the cathode electrode ( 42 a ) are designed to be in contact with blood, and the heart stimulating electrode ( 32 ) and the electrocardiographic information recording electrode ( 53 ) are in contact with the myocardial tissue. The anode ( 41 ) is composed of an anode electrode ( 41 a ) and an immobile layer ( 41 b ) coating the surface of the anode electrode ( 41 a ). A gold electrode, etc. is preferably used as the anode electrode ( 41 a ). Oxidative enzymes of biological fuels and mediators necessary for the oxidation of biological fuels are immobilized on the surface of the anode electrode ( 41 a ). Carbohydrates are used as biological fuels. Examples of carbohydrates are monosaccharides such as glucose and fructose, disaccharides such as mannitol and sucrose, and pentoses such as xylose and arabinose. Glucose, which can be supplied easily by the body, is preferably used as the fuel. Any oxidative enzymes that oxidize biological fuels can be used in the present invention. For example, enzymes called oxidases and hydrogenases could be used. If glucose is used as the biological fuel, glucose oxidase and glucose dehydrogenase can be used. Glucose dehydrogenase is preferable. Any mediator that can transfer electrons released from the biological fuel to the anode electrode ( 41 a ) can be used in the present invention. Some examples include, but are not limited to, the so-called coenzymes such as flavin adenine dinucleotide phosphate, enzymes such as laccase, quinines such as pyrrolo-quinoline quinine, and osmium complex, as well as their combinations. The oxidative enzymes and mediators are immobilized on the surface of the anode electrode ( 41 a ) to form an immobile layer ( 41 b ). There is no restriction on the method of immobilization, and any method well known to immobilize enzymes onto an electrode surface can be used. For example, a gold disc electrode can be used as the substrate, and aminoethane-thiol is adsorbed on the surface of the gold electrode to form a monomolecular film followed by modification of the amino groups. After that, the method mixes the oxidative enzyme for biological fuel, the mediator and albumin in a beaker. Then glutaraldehyde is added to allow the enzymes and mediators to cross-link with glutaraldehyde and then the mixture is applied to the surface of the gold disc electrode. To ensure that the reaction takes place efficiently at the anode, the immobile layer ( 41 b ) should preferably be designed such that the anode electrode ( 41 a ) does not come into contact with oxygen present in the body. The cathode ( 42 ) is composed of a cathode electrode ( 42 a ). An example of the cathode electrode ( 42 a ) is a platinum electrode. A catalyst to enhance a reaction involving reduction of oxygen is required on the cathode electrode ( 42 a ). The platinum itself can function as the catalyst. To ensure that the reaction takes place efficiently at the cathode, it is desirable to form a coating ( 42 b ) on the surface of the cathode electrode, which will prevent permeation of substances other than oxygen that react with the cathode electrode ( 42 a ), and at the same time allow permeation of oxygen and hydrogen ions. The biological fuel cell ( 40 ) does not have a container filled with electrolyte solution. Instead, the cathode electrode ( 41 a ) and the anode electrode ( 42 a ) are in contact with the blood or body fluid of the body. The blood and body fluid act as the electrolyte solution. In the electrolyte solution, biological fuel and oxygen are constantly supplied by the blood flow, and at the same time metabolic products are dissolved in blood and removed by the blood flow. The supply of biological fuel and oxygen as well as the removal of metabolic products are maintained constant through the mechanism of homeostasis. Next, the action of the biological fuel cell ( 40 ) will be discussed. Biological fuel is dissolved in blood and body fluid and supplied to the anode ( 41 ) surface. The biological fuel supplied to the anode ( 41 ) surface is oxidized by the action of the biological fuel oxidative enzyme immobilized in the immobile layer ( 41 b ), producing carbon dioxide, hydrogen ion and intermediate metabolites, as well as electrons. Carbon dioxide, hydrogen ion and intermediate metabolites are dissolved in blood or body fluid to be excreted. Electrons are transferred to the anode electrode ( 41 a ) via mediators. The cathode ( 42 ) surface is supplied with oxygen and hydrogen ions dissolved in blood and body fluid, and these ions react in the presence of electrons transmitted from the anode electrode ( 41 a ) to the cathode electrode ( 42 a ), and form water. This reaction generates an electric current, which is used as the driving power source. Based on the program already saved in the memory ( 7 ) as well as on electrocardiographic information output from the electrocardiographic information detecting means ( 5 ) and information transmitted from the exterior, the control unit ( 2 ) generates control signals and outputs the signals into the heart stimulating means ( 3 ). For instance, the control unit ( 2 ) is equipped with a stimulation timing determining means that decides the timing of stimulation to generate control signals, and a stimulation timing changing means that changes the timing of stimulation to generate control signals. Usually this unit is programmed to generate control signals at stimulation timing at a predetermined frequency. It is also programmed to change the stimulation timing when certain conditions are fulfilled; for instance, in case intracardiac P wave information is detected within a given time interval. Furthermore, this invention can be equipped with a communication means ( 6 ). The communication means ( 6 ) communicates with an external programmer ( 8 ) installed external to the ultra miniature integrated cardiac pacemaker, and is used to change the pacing program saved in the memory ( 7 ). By this means, even after implantation of the ultra miniature integrated cardiac pacemaker in the patient, it is possible to use the external programmer ( 8 ) to change the pacing program saved in the memory ( 7 ) as appropriate for the particular patient. For communication between the external programmer ( 8 ) and communication means ( 6 ) when a patient is implanted with multiple ultra miniature integrated cardiac pacemakers, by setting different frequencies for the individual ultra miniature integrated cardiac pacemakers, for example, it is possible to change the pacing program for each ultra miniature integrated cardiac pacemaker. Also, by conducting spread spectrum communication or by giving each pacemaker an ID, it is possible to change the pacing program of each ultra miniature integrated cardiac pacemaker. Next, the ultra miniature integrated cardiac pacemaker of the second embodiment ( 110 ) of the present invention will be explained. The difference between the ultra miniature integrated cardiac pacemaker in the second embodiment ( 110 ) and the aforementioned ultra miniature integrated cardiac pacemaker of the first embodiment ( 100 ) is that the former has no transmitting means ( 10 ) or receiving means ( 9 ). The ultra miniature integrated cardiac pacemaker of the second embodiment ( 110 ) can be used when there is no need to synchronize movements with other cardiac pacemakers. Based on the control program already saved in the memory ( 7 ) and on electrocardiographic information output from the electrocardiographic information detecting means ( 5 ), the control unit ( 2 ) generates control signals and outputs the signals to the heart stimulating means ( 3 ). The other components are the same as those in the aforementioned ultra miniature integrated cardiac pacemaker of the first embodiment ( 100 ), therefore explanations are omitted. In FIG. 3 , the same numbers are assigned to components identical to those in the first embodiment ( 100 ) as shown in FIG. 1 . Next, the ultra miniature integrated cardiac pacemaker of the third embodiment ( 120 ) of this invention will be explained. FIG. 4 is a simplified block diagram of the ultra miniature integrated cardiac pacemaker in this embodiment ( 120 ). The difference between the ultra miniature integrated cardiac pacemaker in this embodiment ( 120 ) and the aforementioned ultra miniature integrated cardiac pacemaker of the first embodiment is that the former has no receiving means ( 9 ). By sending the control signals to the exterior (such as other cardiac pacemakers) via carrier waves, the ultra miniature integrated cardiac pacemaker ( 120 ) is able to synchronize and operate with, for instance, one or more other cardiac pacemakers. Based on the control program already saved in the memory ( 7 ) and electrocardiographic information output from the electrocardiographic information detecting means ( 5 ), the control unit ( 2 ) generates control signals and outputs the signals to the heart stimulating means ( 3 ). The other components are the same as those in the aforementioned ultra miniature integrated cardiac pacemaker of the first embodiment, therefore explanations are omitted. In FIG. 4 , the same numbers are assigned to components identical to those in the ultra miniature integrated cardiac pacemaker in accordance with the first and second embodiments shown in FIGS. 1 and 3 . Next, the ultra miniature integrated cardiac pacemaker of the fourth embodiment ( 130 ) of this invention will be explained. The difference between the ultra miniature integrated cardiac pacemaker in this embodiment ( 130 ) and the aforementioned ultra miniature integrated cardiac pacemaker in the first embodiment is that the former has no transmitting means ( 10 ) to send control signals and/or electrocardiographic information to the exterior. Through the receiving means ( 9 ) that receives information from the exterior, for example, from other cardiac pacemakers, the ultra miniature integrated cardiac pacemaker ( 130 ) is able to synchronize and operate with other cardiac pacemakers. Based on the control program already saved in the memory ( 7 ), as well as electrocardiographic information output from the electrocardiographic information detecting means ( 5 ) and information transmitted from the exterior, the control unit ( 2 ) generates control signals and outputs the signals to the heart stimulating means ( 3 ). The other components are the same as those in the aforementioned ultra miniature integrated cardiac pacemaker of the first embodiment, therefore explanations are omitted. In FIG. 5 , the same numbers are assigned to components identical to those in the ultra miniature integrated cardiac pacemakers in accordance with the first three embodiments shown in FIGS. 1 , 3 and 4 . In the ultra miniature integrated cardiac pacemakers of the first four embodiments, the electrocardiographic information recording electrodes ( 53 ) and the heart stimulating electrode ( 32 ) are shown as separate components. In reality, the electrocardiographic information recording electrode ( 53 ) and the heart stimulating electrode ( 32 ) may be shared. Moreover, the receiving unit ( 91 ) and the transmitting unit ( 12 ) are shown as separate components; however, the receiving unit ( 91 ) and the transmitting unit ( 12 ) may also be shared. Furthermore, by installing in the patient a sensor that measures body temperature and blood pressure and outputting the biological information obtained from these sensors to the control unit ( 2 ) of the ultra miniature integrated cardiac pacemakers of the first four embodiments, the control unit ( 2 ) is able to generate control signals based on the biological data. In addition, for the ultra miniature integrated cardiac pacemakers of the first four embodiments, there is no particular restriction on the method of implanting the pacemaker in the heart and conventional methods for catheterization may be adopted. For instance, implantation may be done by attaching the ultra miniature integrated cardiac pacemaker to the tip of a catheter and inserting it into the predetermined position inside the heart, and then withdrawing only the catheter after fixing the pacemaker in the endocardium. In the ultra miniature integrated cardiac pacemakers of the invention, the generator main body and the electrodes are integrated, thus obviating the need for lead wires. Therefore, the ultra miniature integrated cardiac pacemakers of the invention can be made of a size of only 2 to 3 mm in diameter. There is no need to make a wide incision in the chest wall to implant the generator main body. Next, a cardiac pacing system according to this invention using the aforementioned ultra miniature integrated cardiac pacemakers in accordance with the first four embodiments of this invention will be described while referring to the diagrams. FIG. 6 is a schematic diagram illustrating the outline of one embodiment of the cardiac pacing system. One ultra miniature integrated cardiac pacemaker ( 111 ) is implanted into the atrial endocardium of the patient. In FIG. 6 as well as in FIGS. 7 to 10 to be described below, H indicates the heart. The cardiac pacing system in this embodiment is preferred in cases where the atrium has lost the ability to keep pace although the electrical activity in the atrium and the electrical activity in the ventricle remain synchronized. For example, it may be indicated for patients with sick sinus syndrome in whom only sinus node function is impaired, while intra-atrial conduction and atrio-ventricular conduction are preserved. The ultra miniature integrated cardiac pacemaker ( 111 ) implanted in the atrium is equipped with a control unit that outputs control signals, a heart stimulating means that responds to the control signals and electrically stimulates the atrial muscle, and an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac P wave information. It is designed such that the detected electrocardiographic information is output into the control unit. In other words, although the ultra miniature integrated cardiac pacemaker of the second embodiment of this invention is preferably used, the ultra miniature integrated cardiac pacemaker in accordance with the first, third and fourth embodiments can also be used as long as they possess the above-mentioned designs. Also, the control unit is equipped with a stimulation timing determining means that decides the timing of stimulation to generate control signals, and a stimulation timing changing means that changes the timing of stimulation to generate control signals. One example of operation of the cardiac pacing system in this embodiment will be explained below. By the stimulation timing determining means, control signals are generated according to a predetermined stimulation timing and the atrial endocardium is stimulated electrically. This results in excitation and contraction of the atrial myocardium, while at the same time this stimulus is conducted to the atrioventricular node through intra-atrial conduction pathway. Then, from the atrioventricular node, the stimulus is conducted to the His bundle, the left and right bundle branch, the Purkinje fiber and finally exciting the ventricular myocardium, resulting in a normal heart beat. Even in sick sinus syndrome, a spontaneous heart beat may occur. If the electrocardiographic information detecting means detects spontaneous intracardiac P wave information within a given predetermined time from the prior heart beat, this spontaneous intracardiac P wave information is output into the control unit, meanwhile the timing of stimulation to generate control signals is changed by the stimulation timing changing means of the control unit, and atrial pacing is suppressed. In case spontaneous intracardiac P wave information is not detected within a given time interval after the detection of prior intracardiac P wave information, the atrial myocardium will be stimulated electrically according to the predetermined stimulation timing. By placing the above-mentioned ultra miniature integrated cardiac pacemaker in the ventricular endocardium of the patient, it is possible to stimulate the ventricular myocardium. By applying this pacemaker to patients who have normal sinus node function and only impaired atrioventricular conduction, it is possible to maintain the clinically required minimal number of ventricular contraction although there is no synchrony between the atrium and ventricle. Next, a distributed cardiac pacing system according to another embodiment will be explained while referring to the diagrams. FIG. 7 is a schematic diagram illustrating an outline of the distributed cardiac pacing system according to this embodiment. The schematic diagram shows one electrocardiographic information detecting device ( 200 ) in the atrial endocardium and one ultra miniature integrated cardiac pacemaker in accordance with this invention ( 131 ) in the ventricular endocardium. FIG. 8 is a block diagram illustrating the outline of the electrocardiographic information detecting device ( 200 ). The distributed cardiac pacing system in this embodiment is indicated for patients who have normal sinus node function and whose atrioventricular conduction is only impaired. In detail, the electrocardiographic information detecting device ( 200 ) placed in the atrial endocardium detects electrocardiographic information including at least spontaneous intracardiac P wave information. The detected electrocardiographic information including spontaneous intracardiac P wave information is transmitted to the ultra miniature integrated cardiac pacemaker ( 131 ) placed in the ventricular endocardium. Upon receiving the electrocardiographic information of the spontaneous intracardiac P wave information from the electrocardiographic information detecting device ( 200 ) and after a given lag (atrioventricular delay equivalent to the PQ interval in the electrocardiogram), the ultra miniature integrated cardiac pacemaker ( 131 ) conducts ventricular pacing by electrically stimulating the ventricular myocardium by the heart stimulating means. Even in patients with impaired atrioventricular conduction, spontaneous ventricular contraction may occur. In these patients, if ventricular contraction occurs (in case of detection of spontaneous intracardiac QRS complex information) within a given time (atrioventricular delay) after the detection of spontaneous intracardiac P wave information, the stimulation timing is changed and ventricular pacing is not conducted. FIG. 8 is a block diagram illustrating the outline of the electrocardiographic information detection device ( 200 ) placed in the atrial endocardium. The electrocardiographic information detection device ( 200 ) is composed of an electrocardiographic information detecting means ( 5 ) that detects the electrocardiographic information including at least intracardiac P wave information and outputs the electrocardiographic data, a transmitting means that sends electrocardiographic information ( 10 ), and a control unit ( 2 ). In the electrocardiographic information detection device ( 200 ) shown in the diagram, the electrocardiographic information detecting means ( 5 ) is composed of two electrocardiographic information recording electrodes ( 53 ) that detect electrocardiographic information, an amplifying unit ( 51 ) that amplifies the electrocardiographic information ( 51 ), and an A/D conversion unit ( 52 ) that converts the electrocardiographic information into digital information. Moreover, in the electrocardiographic information detection device ( 200 ) shown in the diagram, the transmitting means ( 10 ) is composed of a modulating unit ( 11 ) that inputs and modulates the electrocardiographic information output from the control unit ( 2 ), and a transmitting unit ( 12 ) that sends the modulated electrocardiographic information by specified carrier wave. The modulated electrocardiographic information is sent to the ultra miniature integrated cardiac pacemaker ( 131 ) placed in the ventricular endocardium. The ultra miniature integrated cardiac pacemaker ( 131 ) placed in the ventricle is composed of a control unit that outputs control signals, a heart stimulating means that responds to the control signal and electrically stimulates the ventricular myocardium, an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac QRS complexes, and a receiving means that receives and demodulates the electrocardiographic information sent from the electrocardiographic information detection device ( 200 ) placed in the atrium. It is designed such that the electrocardiographic information detected by the electrocardiographic detecting means and the electrocardiographic information sent from elsewhere is input into the control unit. Therefore, in the distributed cardiac pacing system of this embodiment, the ultra miniature integrated cardiac pacemakers of the fourth embodiment are preferably used as the ultra miniature integrated cardiac pacemakers placed in the ventricular endocardium, but the ultra miniature integrated cardiac pacemakers of the first embodiment can also be used without a problem. Furthermore, the control unit is equipped with a stimulation timing determining means that decides the timing of stimulation to generate control signals, and a stimulation timing changing means that changes the timing of stimulation to generate control signals. One example of operation of the distributed cardiac pacing system in this embodiment will be explained below. Usually, the ventricle is paced by the generation of control signals at a stimulation timing determined by the stimulation timing determining device [pacing after a given time interval (atrioventricular delay) from the detection of intracardiac P wave information]. If spontaneous intracardiac QRS complex information is detected within a given time interval (atrioventricular delay) after the detection of intracardiac P wave information, the timing of stimulation to generate control signals is changed by the stimulation timing changing means, and control signals are not generated. The ultra miniature integrated cardiac pacemaker ( 131 ) is preferably designed such that the ventricle is paced at regular intervals if no intracardiac P wave information is sent from the electrocardiographic information detection device ( 200 ) within a given time interval after intracardiac QRS complex information is detected (due to spontaneous ventricular contraction or due to stimulation by a cardiac pacemaker). This design will assure safety if sinus arrest or sinoatrial block occurs. Next, the distributed cardiac pacing system in another embodiment will be explained while referring to the diagram. FIG. 9 is a schematic diagram illustrating a distributed cardiac pacing system according to this embodiment. The diagram shows a first ultra miniature integrated cardiac pacemaker ( 101 ) placed in the atrial endocardium and a second ultra miniature integrated cardiac pacemaker ( 102 ) placed in the ventricular endocardium. The distributed cardiac pacing system in this embodiment may be indicated for patients with malfunction of the sinus node together with impaired atrioventricular conduction. In other words, this pacemaker is indicated for patients with sick sinus syndrome with manifestations of both arrest of sinus function and atrioventricular block. One example of operation of the distributed cardiac pacing system in this embodiment will be explained. The first ultra miniature integrated cardiac pacemaker ( 101 ) placed in the atrial endocardium outputs control signals and paces the atrium by the heart stimulating means. This control signal (and/or electrocardiographic information of atrium) is modulated into carrier waves and transmitted to the second ultra miniature integrated cardiac pacemaker ( 102 ) placed in the ventricular endocardium. Upon receiving the control signals (and/or electrocardiographic information of the atrium) from the first ultra miniature integrated cardiac pacemaker ( 101 ), the second ultra miniature integrated cardiac pacemaker ( 102 ) outputs control signals with a given delay (atrioventricular delay equivalent to the PQ interval on electrocardiogram) after the atrial pacing by the first ultra miniature integrated cardiac pacemaker ( 102 ), and electrically stimulates the ventricular myocardium to conduct ventricular pacing. Furthermore, this control signal (and/or electrocardiographic information of the ventricle) is modulated into a carrier wave and transmitted to the first ultra miniature integrated cardiac pacemaker ( 101 ). The first ultra miniature integrated cardiac pacemaker ( 101 ) suppresses detection of intracardiac P wave for a given time interval after receiving the control signal (and/or electrocardiographic information of the ventricle) from the second ultra miniature integrated cardiac pacemaker ( 102 ). Thereafter, the first ultra miniature integrated cardiac pacemaker ( 101 ) outputs control signals at a stimulation timing according to a predetermined rate, and stimulates the atrium. By repeating the above, it is possible to pace the heart and mimic the natural physiological state. Even patients with sick sinus syndrome with manifestations of both arrest of sinus function and atrioventricular block may generate spontaneous ventricular contraction or atrial contraction. If spontaneous intracardiac P wave information is detected within a given time from the prior heart beat, then the atrial pacing is suppressed. Moreover, if spontaneous intracardiac QRS complex information is detected within a given time interval (atrioventricular delay) after the detection of intracardiac P wave information (spontaneous or due to the first ultra miniature integrated cardiac pacemaker), then ventricular pacing is suppressed. The first ultra miniature integrated cardiac pacemaker ( 101 ) placed in the atrial endocardium is equipped with a control unit that outputs control signals, a heart stimulating means that responds to the control signal and electrically stimulates the atrial myocardium, an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac P wave information, a transmitting means that modulates the control signal or electrocardiographic information and sends the information to the second ultra miniature integrated cardiac pacemaker ( 102 ) placed in the ventricle, and a receiving means that receives and demodulates the control signal or electrocardiographic information sent from the second ultra miniature integrated cardiac pacemaker ( 102 ) placed in the ventricle. The pacemaker is designed such that the control signal and electrocardiographic information sent from the second ultra miniature integrated cardiac pacemaker ( 102 ) are input into the control unit. Therefore, in the distributed cardiac pacing system of this embodiment ( 101 ), the ultra miniature integrated cardiac pacemaker of the first embodiment is preferably used as the first ultra miniature integrated cardiac pacemaker ( 101 ). The second ultra miniature integrated cardiac pacemaker ( 102 ) is equipped with a control unit that outputs control signals, a heart stimulating means that responds to the control signal and electrically stimulates the ventricular myocardium, an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac QRS complex information, a transmitting means that modulates the control signal or electrocardiographic information and sends the information to the first ultra miniature integrated cardiac pacemaker ( 101 ), and a receiving means that receives and demodulates the control signal or electrocardiographic information sent by the first ultra miniature integrated cardiac pacemaker ( 101 ) placed in the atrium. The pacemaker is designed such that the control signal and electrocardiographic information sent from the first ultra miniature integrated cardiac pacemaker ( 101 ) are input into the control unit. Therefore, in the distributed cardiac pacing system of this embodiment, the abovementioned ultra miniature integrated cardiac pacemaker of the first embodiment is preferably used as the second ultra miniature integrated cardiac pacemaker ( 102 ). In the first ultra miniature integrated cardiac pacemaker ( 101 ), the control unit is equipped with a stimulation timing determining means that decides the timing of stimulation to generate control signals, and a stimulation timing changing means that changes the timing of stimulation to generate control signals. Usually, the stimulation timing determining means decides the timing of stimulation of control signal generation, and then generates control signals to conduct atrial pacing. One example of operation of the first ultra miniature integrated cardiac pacemaker ( 101 ) will be explained. If the electrocardiographic information detecting means detects spontaneous intracardiac P wave within a given time from the prior heart beat, the timing of stimulation to generate control signals is changed, a control signal is not generated and atrial pacing is not conducted. If the electrocardiographic information detecting means does not detect spontaneous intracardiac P wave information within a given time interval from the last heart beat, then a control signal is generated and atrial pacing is conducted. Moreover, in the control unit, if the control signal is generated or spontaneous intracardiac P wave information is detected, the information is sent from the transmitting unit to the second ultra miniature integrated cardiac pacemaker ( 102 ). In the second ultra miniature integrated cardiac pacemaker ( 102 ), the control unit is equipped with a stimulation timing determining means that decides the timing of stimulation to generate control signals, and a stimulation timing changing means that changes the timing of stimulation to generate control signals. One example of operation of the second ultra miniature integrated cardiac pacemaker ( 102 ) will be explained. Usually, a control signal is generated at a timing predetermined by the timing determining means [the control signal is generated at a given time interval (atrioventricular delay) after the control signal or intracardiac P wave information is sent from the first ultra miniature integrated cardiac pacemaker ( 101 )]. If spontaneous intracardiac QRS complex information is detected within a given time (atrioventricular delay), the timing of stimulation to generate control signals is changed by the stimulation timing changing means and ventricular pacing is not conducted. Moreover, in the control unit, if a control signal is generated or spontaneous intracardiac QRS wave information is detected, the information is sent from the transmitting unit to the first ultra miniature integrated cardiac pacemaker ( 101 ). The first ultra miniature integrated cardiac pacemaker ( 101 ) suppresses the detection of intracardiac P wave information for a given time interval after receiving the control signal (or electrocardiographic information of the ventricle) from the second ultra miniature integrated cardiac pacemaker ( 102 ). This design is essential to prevent the complication of so called pacemaker tachycardia caused by the following mechanism: when intracardiac QRS complex due to spontaneous ventricular contraction is conducted retrograde to the atrium, the first ultra miniature integrated cardiac pacemaker detects intracardiac P wave information, based on which the second ultra miniature integrated cardiac pacemaker electrically stimulates the ventricle, resulting in repeated electrical stimulation of the ventricle. Next, a distributed cardiac pacing system in another embodiment will be explained while referring to the diagram. FIG. 10 is a schematic diagram illustrating the distributed cardiac pacing system in this embodiment. The diagram shows an electrocardiographic information detecting device ( 200 ) placed in the atrial endocardium and multiple (for example, a total of 4 in FIG. 10 ) ultra miniature integrated cardiac pacemakers ( 102 ) placed in the ventricular endocardium. The distributed cardiac pacing system in this embodiment may be indicated for patients with impaired synchrony of ventricular myocardial contraction leading to lowered ventricular contractility, or patients at risk for fatal arrhythmia. One example of operation of this distributed cardiac pacing system will be explained. The electrocardiographic information detecting device ( 200 ) placed in the atrial endocardium detects electrocardiographic information including at least intracardiac P wave information. The detected electrocardiographic information is sent to multiple ultra miniature integrated cardiac pacemakers ( 102 ) placed in the ventricular endocardium. Once electrocardiographic information is sent from the electrocardiographic information detecting device ( 200 ), multiple ultra miniature integrated cardiac pacemakers ( 102 ) generate control signals to stimulate the ventricular myocardium and pace the ventricle with a delay after atrial contraction in time lags that vary depending on the individual ultra miniature integrated cardiac pacemakers ( 102 ). In other words, once electrocardiographic information is sent from the electrocardiographic information detecting device ( 200 ), the multiple ultra miniature integrated cardiac pacemakers ( 102 ) pace the ventricle after predetermined times depending on the ventricular sites at which the individual ultra miniature integrated cardiac pacemakers ( 102 ) are placed. If spontaneous ventricular contraction occurs, that is, if spontaneous intracardiac QRS complex information is detected within a given time interval (atrioventricular delay) after the detection of intracardiac P wave information, ventricular pacing is suppressed. However, even though spontaneous intracardiac QRS complex information is detected, if the spontaneous beat is not detected within given time intervals at other multiple ultra miniature integrated cardiac pacemakers ( 102 ) placed in the ventricular endocardium, the ventricular pacing at these sites will not be suppressed. In order to realize this, spontaneous intracardiac QRS complex information recorded by a pacemaker ( 102 ) at any site of the ventricle is transmitted to other ventricular pacemakers ( 102 ). Each ventricular pacemaker ( 102 ) mutually receives the signals sent from other ventricular pacemakers ( 102 ). The ultra miniature integrated cardiac pacemaker ( 102 ) placed in the ventricular endocardium is equipped with a control unit that outputs control signals, a heart stimulating means that responds to control signals and electrically stimulates the ventricular myocardium, an electrocardiographic information detecting means that detects the electrocardiographic information including at least intracardiac QRS complex information, a transmitting means that modulates the control signal or electrocardiographic information and sends the information to other ultra miniature cardiac pacemakers placed in the ventricle, and a receiving means that receives and demodulates control signals or electrocardiographic information sent by the electrocardiographic information detecting device ( 200 ) placed in the atrium and other ultra miniature integrated cardiac pacemakers placed in the ventricle. Therefore, in this embodiment, the aforementioned ultra miniature integrated cardiac pacemakers of the first embodiment ( 100 ) are preferably used as the ultra miniature integrated cardiac pacemakers ( 102 ). In addition, the sites where the ultra miniature integrated cardiac pacemakers are to be placed and the number of the pacemakers will be set appropriately in accordance with the patient's symptoms. The control unit of each ultra miniature integrated cardiac pacemaker ( 102 ) is equipped with a stimulation timing determining means that decides the timing of stimulation to generate control signals, and a stimulation timing changing means that changes the timing of stimulation to generate control signals. One example of operation of the ultra miniature integrated cardiac pacemaker will be explained. The stimulation timing determining means generates a control signal at a predetermined stimulation timing [generates a control signal at a given time interval (atrioventricular delay) after spontaneous intracardiac P wave information is transmitted from the electrocardiographic information detecting device ( 200 )], and ventricular pacing is conducted. The stimulation timing is different for each of the ultra miniature integrated cardiac pacemakers; in other words, it differs depending on the placement site of the pacemakers in the ventricular endocardium. For example, each ultra miniature integrated cardiac pacemaker ( 102 ) is stimulated with a time lag depending on when the site is stimulated in the normal ventricular beat. But, the above-mentioned combination is not restricted as long as it is a combination that maximally improves the contractility of the heart. This kind of synchronized cardiac contraction also reduces the electrical instability of the ventricle, and is used to prevent arrhythmia in patients with a risk of fatal arrhythmia, and also to prevent pacemaker-induced arrhythmia. The intracardiac QRS complex information detected by the ultra miniature integrated cardiac pacemaker ( 102 ) is transmitted to other ultra miniature integrated cardiac pacemakers via the transmitting means. If a certain ventricular pacemaker detects spontaneous intracardiac QRS complex within the predetermined time but this spontaneous beat is not detected at other ventricular pacemakers within given times, the above-mentioned design ensures that ventricular pacing also takes place in these sites. In the distributed cardiac pacing system, it is possible to place an ultra miniature integrated cardiac pacemaker ( 101 ), instead of the electrocardiographic information detecting device ( 200 ), in the atrial endocardium just like the above-mentioned distributed cardiac pacing system in the previous embodiment. As described in the distributed cardiac pacing system in the previous embodiment (i.e., the third embodiment of the distributed cardiac pacing system), the ultra miniature integrated cardiac pacemaker placed in the atrial endocardium is equipped with a stimulation timing determining means and stimulation timing changing means, and therefore may be used in patients with lowered ventricular contractility accompanying sinus arrest and atrioventricular block, as well as in patients with a risk of fatal arrhythmia accompanying sinus arrest and atrioventricular block. In the distributed cardiac pacing system of this revised embodiment, for the design of the ultra miniature integrated cardiac pacemaker placed in the atrial endocardium, one may adopt the design of the ultra miniature integrated cardiac pacemaker ( 101 ) placed in the atrial endocardium in the above-mentioned distributed cardiac pacing system in accordance with the previous embodiment (i.e., the third embodiment of the distributed cardiac pacing system). Furthermore, in the distributed cardiac pacing system in accordance with this revised embodiment for the design of the ultra miniature integrated cardiac pacemaker placed in the ventricular endocardium, one may adopt the design of the ultra miniature integrated cardiac pacemaker ( 102 ) placed in the ventricular endocardium in the above-mentioned distributed cardiac pacing system in this embodiment (i.e., the fourth embodiment of the distributed cardiac pacing system). The ultra miniature integrated cardiac pacemaker in one embodiment transmits control signals or electrocardiographic information to other ultra miniature integrated cardiac pacemakers and at the same time receives control signals or electrocardiographic information from other ultra miniature integrated cardiac pacemakers; thus it is able to pace the heart in synchrony with other ultra miniature integrated cardiac pacemakers. The ultra miniature integrated cardiac pacemaker in another embodiment does not require lead wires to connect the pacemaker main body with the stimulation electrodes; thus it is able to pace the heart without imposing extra burden on the patient. The ultra miniature integrated cardiac pacemaker in another embodiment transmits control signals or electrocardiographic information to other ultra miniature integrated cardiac pacemakers; thus it is able to pace the heart in synchrony with other ultra miniature integrated cardiac pacemakers. The ultra miniature integrated cardiac pacemaker in yet another embodiment receives control signals or electrocardiographic information from other ultra miniature integrated cardiac pacemakers; thus it is able to pace the heart in synchrony with other ultra miniature integrated cardiac pacemakers. The distributed cardiac pacemaker system in another embodiment can be used for pacing in patients whose atrium has lost the ability to keep pace although the electrical activity in the atrium and the electrical activity in the ventricle remain synchronized. The distributed cardiac pacemaker system in still another embodiment can be used in patients with normal sinus node function but in whom atrioventricular conduction is only impaired. The distributed cardiac pacemaker system in another embodiment can be used in patients whose sinus node is not functioning normally and atrioventricular conduction is also impaired. The distributed cardiac pacemaker system in yet another embodiment can be used in patients who have lost synchrony of contraction among various parts of the ventricle together with lowered ventricular contractility, or patients with arrhythmia. The distributed cardiac pacemaker system in another embodiment can be used in patients with lowered ventricular contractility accompanying sinus arrest and atrioventricular block, as well as patients with a risk of fatal arrhythmia accompanying sinus arrest and atrioventricular block. The present invention provides an ultra miniature integrated cardiac pacemaker and distributed cardiac pacing system which allow pacing of the heart without the need for the conventional lead wires that connect the electrodes with the pacemaker main body, and allow implantation in the heart by catheter manipulation only without incision of the chest wall to reduce burden on the patient. Accordingly, it is to be understood that the embodiments of the invention herein described are merely illustrative of the application of the principles of the invention. Reference herein to details of the illustrated embodiments is not intended to limit the scope of the claims, which themselves recite those features regarded as essential to the invention.

A micro integrated cardiac pacemaker includes a control unit for outputting a control signal according to cardiograph information, heart stimulating means for stimulating heart tissue in response to the control signal, cardiograph information extracting means for extracting cardiograph information and outputting it to the control unit, and a power supply unit for supplying drive power. The power supply unit is a biological fuel cell that takes out electrons by oxidation of a biological fuel. The biological fuel cell includes an anode and a cathode. An oxidase of a biological fuel and a mediator are immobilized on the cathode. Blood and/or body fluid are used as an electrolytic solution, and a biological fuel and oxygen in the blood and/or the fluid are used. The biological fuel cell is attached to the end of a catheter and implanted into the heart, and the catheter is withdrawn, without incising the breast.

BACKGROUND [0001] 1. Technical Field [0002] The present invention relates to a toothbrush, and, in particular, relates to an electric or battery operated toothbrush having fluid jet capabilities. [0003] 2. Background of the Related Art [0004] Various toothbrush devices are commonly known in the art including manual toothbrushes and electrical/battery operated toothbrushes. Examples of such toothbrushes are disclosed in commonly assigned U.S. Pat. Nos.: 6,735,804, 6,597,000 Des. 456,608 and Des. 457,000, the entire contents of each disclosure being incorporated by reference herein. SUMMARY [0005] Accordingly, the present invention relates to further improvements in electrical or battery operated toothbrush assemblies. In accordance with one embodiment of the present disclosure, a powered toothbrush assembly includes an outer housing, a brush head and a fluid nozzle adjacent the brush head, an inner housing disposed within the outer housing and having a motor which is in operative engagement with the brush head to impart motion to the brush head and a pump mechanism disposed within the inner housing. The outer housing and the inner housing define a chamber therebetween for accommodating a fluid. The pump mechanism includes a pump housing having a pump inlet dimensioned to permit entry of the fluid from the chamber and a pump outlet for permitting exit of the fluid from the pump housing, a pump for imparting energy to the fluid entering the pump inlet and directing the fluid to the pump outlet and a conduit in fluid communication with the pump outlet and the fluid nozzle for directing the fluid to the fluid nozzle for release under pressure therefrom. [0006] The pump mechanism may be operable in a first mode of operation for directing air passing through an air inlet adjacent the pump housing and fluidly couplable with the conduit to the fluid nozzle and a second mode of operation for directing the fluid in liquid form contained within the chamber to the fluid nozzle. [0007] A manually activated actuator may be mounted to the outer housing. The actuator is movable between a first condition corresponding to the first mode of operation of the pump mechanism and a second condition corresponding to the second mode of operation of the pump mechanism. [0008] A drive mechanism may be associated with the pump mechanism. The drive mechanism is in operative engagement with the motor to impart motion to the brush head. The drive mechanism may includes a cam member in operative engagement with the motor, an elongated drive member operatively coupled to the cam member and adapted for reciprocal movement upon movement of the cam member, at least one drive gear operatively coupled to the drive member and adapted for reciprocal movement therewith and wherein the brush head includes a plurality of individual bristles. Each bristle may have a bristle gear adapted to cooperatively engage the at least one drive gear, whereby movement of the drive gears causes corresponding rotational movement of the bristle gears and the bristles. [0009] The powered toothbrush may include a liquid check valve adjacent the pump outlet. The liquid check valve is dimensioned to prevent retrograde liquid flow. An air check valve may be adjacent the air inlet, and dimensioned to prevent liquid flow through the air inlet. A pressure valve may be in fluid communication with the fluid conduit and dimensioned to open upon achieving a predetermined pressure in the fluid conduit, to thereby permit release of the liquid into the fluid chamber. [0010] A manually activated power switch may be provided to power the motor. A power source may be in electrical communication with the pump. The power source may include a rechargeable battery. BRIEF DESCRIPTION OF THE DRAWINGS [0011] Various embodiments of the present disclosure arc described hereinbelow with references to the drawings, wherein: [0012] FIGS. 1 and 2 are perspective views of the toothbrush with fluid jet assembly in accordance with the principles of the present invention; [0013] FIG. 3 is a perspective view with parts separated of the toothbrush assembly; [0014] FIG. 4 is a perspective view with portions of the main housing removed illustrating the inner housing; [0015] FIG. 5 is a perspective view with portions of the inner housing removed illustrating components of the motor and the drive mechanism; [0016] FIG. 6 is a side cross-sectional view of the toothbrush assembly; [0017] FIGS. 7 and 8 are perspective views of the drive and pump mechanisms of the toothbrush assembly; [0018] FIGS. 9 and 10 are perspective views of the water pump and associated components of the toothbrush assembly; and [0019] FIGS. 11-13 are views of the water pump illustrating stages of operation of the toothbrush assembly. DETAILED DESCRIPTION OF THE EMBODIMENTS [0020] Referring now to the drawings wherein like reference numerals identify similar components throughout the several views, FIGS. 1-2 illustrate the toothbrush with fluid/water jet assembly in accordance with the principles of the present invention. Toothbrush assembly 100 is electrically or battery operated and has a driven bristle head with fluid jet capabilities for mouth cleansing and food particle removal. [0021] With reference to FIG. 3 , in conjunction with FIGS. 1-2 , toothbrush assembly 100 includes outer main housing 102 , top housing 104 coupled to the main housing 102 and brush head 106 , these components constituting the outer housing of the toothbrush assembly 100 . Although shown as separate units adapted for releasable connection to each other, main housing 102 , top housing 104 , and brush head 106 may be a single monolithic or integral housing unit. Toothbrush assembly 100 further includes a manually activated power or on/off switch 108 and a fluid jet or manually activated fluid actuator 110 with on/off capabilities. [0022] The remaining external components of toothbrush assembly 100 include decorative cover 112 for mounting to main housing 102 , light or LED cover 114 for enclosing a light mounted within main housing 102 and fluid or liquid tank cover 116 . Fluid tank cover 116 is releasably mountable to main housing 102 and permits access to an internal fluid chamber to permit the operator to supply the fluid chamber with fluid. A socket 118 with electrical contacts is disposed on the lower surface of main housing 102 . A release lock 120 is provided to permit release of the top housing 104 and/or brush head 106 . The release lock 120 may be any known locking mechanism selected to releasably connect the components. [0023] Referring now to FIGS. 3-6 , the interior of toothbrush assembly 100 will be discussed. Toothbrush assembly 100 includes internal or inner housing 122 which is fluid proof or tight and accommodates the functional components of the toothbrush assembly 100 . Inner housing 122 includes, or has mounted therein, induction charging coil 124 , rechargeable battery 126 in electrical connection with the induction coil 124 and lamp or LED 128 which is exposed through a lens or cover within the inner housing 122 . Inner housing 122 further encloses motor 130 , a drive or cam mechanism 132 , a pump mechanism 134 associated with the drive mechanism 132 , a conduit 130 in fluid communication with the pump mechanism 134 and with a jet nozzle 138 disposed adjacent rotary bristle head 140 . Motor 130 may be any dc motor suitable for its intended purpose of driving a small appliance, or may be an ac motor. The components of the drive mechanism 132 and the pump mechanism 134 will be discussed in detail hereinbelow. [0024] 100211 Outer housing 102 , 104 and inner housing 122 define an internal chamber 142 therebetween when assembled. Internal chamber 142 is for accommodating fluids, e.g., liquids having antiseptic qualities or the like, or even water, to be supplied to, and distributed by pump mechanism 134 . Tank cover 116 permits access to internal chamber 142 to permit the operator to supply the chamber 142 with the desired fluid. Sealing rings or gaskets 144 , 146 are disposed on the upper and lower areas of inner housing 122 and engage the internal wall of housings 102 , 104 in sealed relation therewith to prevent ingress or egress of fluids relative to the internal chamber 142 . [0025] Referring now to FIGS. 7-8 in conjunction with FIG. 6 , cam or drive mechanism 132 will be described. In one embodiment, drive mechanism 132 includes pinion gear 148 mounted to the output or spindle of motor 130 , crown gear 150 in intermeshing relation with the pinion gear 148 , and drive crank shaft 152 connected to crown gear 150 . The longitudinal axis of the drive crank shaft 152 may be offset from the axis about which the crown gear 150 (e.g., an eccentric gear) rotates and may be connected to the crown gear 150 through an appropriate bearing or the like. Accordingly, rotational movement of pinion gear 148 occurring during operation of motor 130 will cause crown gear 150 to rotate, which, in turn effects drive crank shaft 152 to move in a reciprocal longitudinal motion (in the direction of arrows “k”) with respect to the axis of the crank shaft 152 . Drive crank shaft 152 is connected to stainless steel actuator rod 154 which extends through an opening in water pump housing 156 . [0026] Referring again to FIGS. 5-7 , actuator rod 154 may be connected to another rod element 158 (preferably, plastic) which extends within brush head 106 . Rod element 158 preferably includes at least one or a pair of opposed racks 160 which interact with gears 162 attached to bristles 164 . Reciprocal longitudinal movement of racks 160 during corresponding reciprocal longitudinal movement of rod element 158 causes gears 162 to rotate in corresponding clockwise and counterclockwise directional movements, which in turn, causes bristles 164 to also oscillate or rotate in similar manner. [0027] Referring to FIGS. 9-10 , in conjunction with FIGS. 7-8 , pump mechanism 134 will be discussed. Pump mechanism 134 includes pump housing 156 which at least partially receives water pump crank shaft 166 . Pump housing 156 permits entry and exit of fluids from internal chamber 142 . Specifically, pump housing 156 includes fluid inlet port 168 which is fluidly couplable with internal chamber 142 to permit entry and passage of fluid during activation of pump mechanism 134 . Within pump housing 156 and attached to pump crank shaft 166 is pump or piston 170 which drives the fluid through fluid outlet port 172 during operation of the pump mechanism 156 . [0028] Pump mechanism 134 is actuated through motor 130 which drives crown gear 150 as discussed hereinabove. The longitudinal axis of the pump crank shaft 166 may be offset from the axis about which the crown gear 150 rotates and may be connected to the crown gear 150 through an appropriate bearing or the like. Accordingly, rotational movement of crown gear 150 will effect pump crank shaft 166 to move in a reciprocal longitudinal motion (in the direction of arrows “m”) with respect to the axis of the pump crank shaft 166 . Piston 170 may be pivotally coupled to pump crank shaft 166 and will maintain its vertical orientation through its confinement within pump housing 156 , but will oscillate in an up/down direction during movement of the pump crank shaft 166 . In general, movement of piston 170 will drive the fluid received within fluid inlet port 168 from internal chamber 142 through fluid outlet port 172 . [0029] Referring now to FIGS. 9-10 , further details of pump mechanism 134 will be discussed. Pump mechanism 134 includes a plurality of valves or checks to ensure proper operation of the pump mechanism 134 and/or of the toothbrush assembly 100 . In one embodiment, pump housing 156 includes a number of housing components which accommodate various valves or checks to ensure appropriate delivery of fluids and to prevent the potential buildup of fluid pressure which may otherwise have a detrimental effect on the motor and its components. Pump housing 156 includes top, middle and bottom housings 156 a , 156 b , 156 c , which are assembled together to form a single unit. A valve and sealing member 174 is mounted between bottom and middle housings 156 c , 156 b . Valve and sealing member 174 may be a gasket member or the like and may be fabricated from a suitable elastomeric material or any other suitable material. Valve and sealing member 174 includes a plurality of slits, openings or apertures which may be dimensioned and adapted to function as valves (e.g., to open, close or partially open) in response to pressure (e.g., both, positive or negative). In one embodiment, valve and sealing member 174 includes water inlet valve 176 adjacent or in line with fluid inlet port 168 , check valve 178 adjacent to or in line with fluid conduit 180 of fluid exit port 172 of the pump housing 156 and over pressure valve 182 for opening in the event a blockage exists within fluid conduit 136 leading to jet nozzle 138 or within the jet nozzle 138 itself. Upon opening of the over pressure valve 182 fluid will be deposited back into internal chamber 142 . Over pressure valve 182 may be controlled via spring 186 , which engages the lower surface of the valve 182 . The constant force of spring 186 may be selected to permit release of valve 182 when a predetermined pressure is achieved within fluid conduit 136 . The threshold level is chosen to avoid pressure build up and potential damage to the component parts. A check valve 188 is in fluid communication with the air intake channel or conduit 190 within each of pump housings 156 a , 156 b , 156 c. [0030] Operation of the toothbrush assembly 100 will now be discussed. With reference to FIG. 11 , in a first mode of operation with the power on via actuation of switch 108 and fluid actuator 110 in the off position essentially maintaining air intake channel 190 in the open position as depicted in FIG. 11 , air will flow through pump mechanism 134 along path “a” and exit fluid outlet port 172 for dispensing through fluid conduit 136 and out jet nozzle 138 . Simultaneously therewith, drive mechanism 132 will be actuated to rotate bristles 164 in the aforedescribed manner. In the second stage of operation depicted in FIG. 12 , fluid actuator 110 is depressed or activated, which closes air intake channel 190 . Thus, fluid or liquid is received from internal chamber 142 within fluid inlet port 168 , passing through water inlet valve 176 ( FIG. 10 ) which opens to permit passage of the fluid into the pump housing 134 through fluid channel or conduit 180 and out fluid exit port 172 of the pump housing 156 . The fluid path is identified by arrow “f”. The fluid is pumped under pressure via piston 170 and through conduit 130 to exit jet nozzle 138 in bristle head 140 . In this capacity, the jet nozzle 138 may be used to provide additional cleansing capacities or remove debris from the teeth. During the second stage of operation, check valve 178 prevents retrograde movement of the fluid back into the internal chamber 142 . Also, during this stage or phase of the operation, the fluid is prevented from entering air channel 190 by way of air check valve 188 . During operation, in the event there is blockage within jet nozzle 138 or fluid conduit 136 , pressure valve 182 may be activated or released against spring 186 to permit exit of the fluids back into the internal chamber 142 , thereby minimizing the potential of increased pressure in the pump mechanism 134 , which, may otherwise damage the components of the pump. Pressure valve 182 may be spring activated having spring 186 dimensioned to release or compress upon achieving a predetermined pressure within conduit 136 . [0031] As indicated hereinabove, the various check valves may be slit, gasket zero closure valves adapted to open or close in response to pressure differential. Valves may be defined within an elastomeric component or may be incorporated as an integral component in check valve. One skilled in the art may readily determine the [0032] Although the illustrative embodiments of the present disclosure have been described herein with reference to the accompanying drawings, the above description, disclosure, and figures should not be construed as limiting, but merely as exemplifications of particular embodiments. It is to be understood, therefore, that the disclosure is not limited to those precise embodiments, and that various other changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the disclosure.

A powered toothbrush assembly ( 100 ) includes an outer housing ( 102, 104 ), a brush head ( 106 ) and a fluid nozzle ( 138 ) adjacent the brush head ( 106 ), an inner housing ( 122 ) disposed within the outer housing ( 102,104 ) and having a motor ( 130 ) which is in operative engagement with the brush head ( 106 ) to impart motion to the brush head ( 106 ) and a pump mechanism ( 134 ) disposed within the inner housing ( 122 ). The outer housing ( 102,104 ) and the inner housing ( 122 ) define a chamber ( 142 ) therebetween for accommodating a fluid. The pump mechanism ( 134 ) includes a pump housing ( 156 ) having a pump inlet ( 168 ) dimensioned to permit entry of the fluid from the chamber ( 142 ) and a pump outlet ( 172 ) for permitting exit of the fluid from the pump housing ( 156 ), a pump ( 170 ) for imparting energy to the fluid entering the pump inlet ( 168 ) and directing the fluid to the pump outlet ( 172 ) and a conduit ( 180 ) in fluid communication with the pump outlet ( 172 ) and the fluid nozzle ( 138 ) for directing the fluid to the fluid nozzle ( 138 ) for release under pressure therefrom.

TECHNICAL FIELD The present invention relates generally to an apparatus and method of processing logs, and, more specifically, to an apparatus and method which provides for delimbing, cut-to-length, and log handling functions in a single assembly. BACKGROUND In the forestry industry, it is common practice for a logging operator to cut down trees by hand or using a harvester-type machine, transport the logs (logs is used herein to refer to felled trees) to a central processing/loading location using a forwarder or the like, delimb the logs with a delimbing machine or by hand, optionally cut the logs to length by hand or using a work machine, and load the whole or cut logs onto a truck or other transport using a log loader. As is intuitively obvious, this sort of operation requires a great number of different work machines which must be purchased and maintained, necessitating a wide range of replacement parts be available. The machines also are frequently idle when the supply feed of logs is uneven, and a breakdown of one machine can cause the entire operation to stop entirely. All of the above may cause the logging operator to incur great expense and loss of productivity. It is thus common in the art for work machines to perform more than one of the aforementioned functions, in an attempt to reduce the number of machines and operators needed for a successful logging operation. However, many of these combination machines are mechanically quite complicated and perform multiple jobs poorly in comparison to single-function machines, which has resulted in a tendency for logging operators to continue to use the single-function machines. Such a combination machine is disclosed in U.S. Pat. No. 5,628,354, issued May 13, 1997 to Aloysius Kingston (hereafter referenced as '354). '354 relates to a tree delimbing and severing attachment, which is optionally mounted on the trailer of a forwarder. The '354 machine may be used to process felled trees at the felling location and to carry logs therefrom to a forest road and then the central processing/loading location. '354, however, may have the disadvantages of scattering the discard material about the logging site, requiring multiple grapple cycles to transfer the cut-to-length logs to the forwarder trailer, and requiring a highly skilled operator to maneuver and delimb the logs in the often tight confines of a felling location, among others. Accordingly, the art has sought a method and apparatus of processing logs which: successfully and efficiently combines several logging work functions in one apparatus; allows for logs to be processed in a central location which may be chosen to eliminate spacial constraints; performs several operations without requiring multiple instances of handling/moving the same log; may be used in a timely and efficient manner; and is more economical to manufacture and use. The present invention is directed to overcoming one or more of the problems as set forth above. SUMMARY OF THE INVENTION In an embodiment of the present invention, an apparatus for processing logs is provided. The apparatus includes a linkage having a boom and a stick. The boom is adapted for attachment to a support platform. A delimbing assembly is connected to the boom, and a loading assembly is connected to the stick. In an embodiment of the present invention, a method of processing logs using a log processing apparatus is provided. The method includes the steps of picking up a log, delimbing the log, and placing the log into a desired position. In an embodiment of the present invention, a work machine for processing and loading logs is provided. The work machine includes a body, an engine, propulsion means, an operator compartment, a linkage connected to the body, and a log processing assembly connected to at least one of the linkage and the body. The log processing assembly includes a delimbing portion and a loading portion. In an embodiment of the present invention, a method of processing logs is provided. The method includes the steps of picking up a log with a loading assembly of a work machine and delimbing the log with a delimber of the work machine. The method also includes the steps of determining at least one of a total length value, a partial length value, and a girth value of the log with a measuring system of the work machine and determining a desired length or lengths of the log using at least one of the total length value, partial length value, and girth value of the log. The method also includes the steps of cutting the log to the desired length or lengths with one or more saws of the work machine and placing the length or lengths of the log in a predetermined position with the loading assembly of the work machine. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of the apparatus of a preferred embodiment of the present invention; and FIG. 2 is a side view of the apparatus mounted on a work machine of a preferred embodiment of the present invention. DETAILED DESCRIPTION A preferred embodiment of the present invention provides an apparatus and method of processing logs. The following description uses an excavator as an example only. This invention may be applied to other types of work machines. Referring to FIG. 1, a log processing apparatus 100 is provided. The apparatus 100 has a linkage 102 . The linkage 102 includes a boom 104 and a stick 106 . The boom 104 is attachable to a support platform (not shown). The stick 106 is connected to the boom 104 for relative movement thereto. The apparatus 100 also includes a delimbing assembly 108 and a loading assembly 110 . The delimbing assembly 108 and the loading assembly 110 are each attached to one of the boom 104 and stick 106 . Preferably, the delimbing assembly 108 is attached to the boom 104 , and the loading assembly 110 is attached to the stick 106 . The delimbing assembly 108 preferably includes a log delimbing support system 112 , delimbing knives 114 , and a butt saw assembly 116 . The log delimbing support system 112 acts to provide support for the log as it is being delimbed. The term “delimbing” is meant to refer to any combination of delimbing and debarking operations herein. A preferred embodiment of the delimbing support system 112 is shown in FIG. 1 . This embodiment includes a support trough 118 , a hold-down roller 120 , and a drive mechanism 122 . The loading assembly 110 preferably includes a grapple 124 , a topping saw assembly 126 , and a log loading support system 128 . The log loading support system 128 acts to provide leverage and support for the log as it is being loaded and may act to steady the log. A preferred embodiment of the log loading support system 128 is shown in FIG. 1 . This embodiment includes a commonly used heel assembly 130 . Optionally, the apparatus 100 also includes a log measurement system (not shown). The log measurement system has at least one measurement sensor 132 and produces at least one log measurement signal. This signal indicates one or more of a longitudinal characteristic (“length”) or a diametrical characteristic (“girth” or “diameter”), of all or a portion of the log. In a preferred embodiment of the present invention, shown in FIG. 1, the linkage 102 includes one or more linkage joints 132 ′ at the connections between the various components of the linkage 102 , and each linkage sensor 132 ′ includes a measurement sensor 132 . The measurement sensors 132 can measure the relative angles of the components of the linkage 102 , and, knowing the length of the components, the log measurement system can determine a position in space of the grapple 124 , the topping saw assembly 126 , the butt saw assembly 116 , or any other portion of the apparatus 100 . Once the relative position of the components of the apparatus 100 is known, one skilled in the art can determine the length of the log or a portion thereof being processed by the apparatus 100 , and thereby accurately cut the log to a desired length or lengths. The butt saw assembly 116 and the topping saw assembly 126 can be bar saws, disk saws, shears, chainsaws, flails, or any other known means to sever or cut the log in a desirable manner. Each of the butt saw assembly 116 and the topping saw assembly 126 can be mounted at any convenient location on the apparatus 100 . The presence of either or both of a butt saw assembly 116 and a topping saw assembly 126 is not required for proper function of the apparatus 100 . Referring now to FIG. 2, the apparatus 100 is shown mounted on a work machine 200 . The work machine 200 shown in FIG. 2 is commonly known as an excavator or hydraulic excavator. The work machine 200 includes a body 202 , an engine 204 , propulsion means 206 , an operator compartment 208 , and the apparatus 100 . In FIG. 2, the work machine 200 acts as a support platform for the apparatus 100 , but various other embodiments of a support platform can be envisioned, such as, but not limited to, a stanchion, pier, platform, trailer, footing, and the like. While aspects of the present invention have been particularly shown and described with reference to the preferred embodiment above, it will be understood by those skilled in the art that various additional embodiments may be contemplated without departing from the spirit and scope of the present invention. For example, the log could have been previously at least partially delimbed, the log measurements could be obtained differently, or the linkage could have more sections in addition to the boom and stick. However, a device or method incorporating such an embodiment should be understood to fall within the scope of the present invention as determined based upon the claims below and any equivalents thereof. INDUSTRIAL APPLICABILITY In the following description, the apparatus 100 of the present invention will be assumed to be mounted upon a work machine 200 and located at a central processing/loading location. The apparatus 100 will be referred to as a “processor” 100 . These terms are used for convenience of reference and should not be construed to limit the scope of the invention in any way. The following describes the operation of a preferred embodiment of the present invention. During a logging operation at a forest location, trees are cut by a harvester and the resulting logs are transported to the central processing/loading location by a forwarder. The logs, still carrying-bark and limbs, are unloaded from the forwarder. The processor 100 then picks up each log with its grapple 124 and feeds it into the delimbing assembly 108 in a known manner. The delimbing knives 114 remove the limbs and/or bark from the log as the log is passed between them, either on the intake or output pass of the log. When the log is sufficiently seated in the delimbing assembly 108 , either the grapple 124 or a combination of the hold-down roller 120 and a drive mechanism 122 provides motive power to draw the log (intake pass) between the delimbing knives 114 in a direction away from the loading assembly 110 while a support trough 118 serves to support the weight of the length of the log. A motive power is then applied to move the log in a direction toward the loading assembly 110 (output pass). Optionally, a topping saw assembly 126 and/or butt saw assembly 116 may be employed in a known manner, manually or automatically, to remove one or more ends of the log as the tree is being delimbed or loaded. In the case of a whole-tree operation, once the log is delimbed, it is removed from the delimbing assembly 108 on its output pass by the loading assembly 110 and placed/loaded in a predetermined location by the operator, using the loading assembly 110 . If the log is being processed for a cut-to-length operation, a measurement system may be employed to measure the log's length, partial length, girth, or any other property to determine when a desired portion of the log has passed from the delimbing assembly 108 on the output pass. The delimbed log is removed from the delimbing assembly 108 as above, until a desired length of the log has been removed from the delimbing assembly 108 . The topping saw assembly 126 and/or butt saw assembly 116 may then be employed to cut the log at that position, thus producing a child log from the parent log. The child log is then placed into a predetermined location as above and the parent log continues its output pass. This operation may be repeated as needed to produce a desired number of child logs. The measurement system also may be used to monitor log production, waste generation, or any other properties which may be determined from the log's length, partial length, and girth. The apparatus and method of certain embodiments of the present invention, when compared with other methods and apparatus, may have the advantages of: successfully and efficiently combining several logging work functions in one apparatus; allowing for logs to be processed in a central location which may be chosen to eliminate spacial constraints; performing several operations without requiring multiple instances of handling/moving the same log; being used in a timely and efficient manner; and being more economical to manufacture and use. Such advantages are particularly worthy of incorporating into the design, manufacture, and operation of forestry machines. In addition, the present invention may provide other advantages that have not yet been discovered. It should be understood that while a preferred embodiment is described in connection with an excavator, the present invention is readily adaptable to provide similar functions for other work machines. Other aspects, objects, and advantages of the present invention can be obtained from a study of the drawings, the disclosure, and the appended claims.

The present invention provides an apparatus and method of processing logs. The apparatus includes a linkage having a boom and a stick. The boom is adapted for attachment to a support platform. A delimbing assembly is connected to the boom, and a loading assembly is connected to the stick. The method includes the steps of picking up a log, delimbing the log, and placing the log into a desired position.

FIELD OF THE INVENTION This invention relates generally to a circular knitting machine which may be easily converted for permitting a limited range of needle cylinders and dials of different diameters to be used on the knitting machine, and more particularly to such a machine in which the number of parts to be replaced during conversion between a limited range of needle cylinder and dials of different diameters is substantially reduced. BACKGROUND OF THE INVENTION Conventional large diameter circular knitting machines are normally provided with a set of segmental cylinder knitting cam support blocks surrounding the needle cylinder of a given diameter, and a set of segmental dial knitting cam support blocks positioned on the dial for actuating the respective cylinder and dial needles at each yarn feeder. A plurality of yarn feeders and knitting cam segments are provided on each of the segmental knitting cam support blocks and spaced from each other so as to comprise an annular body. The number of yarn feeders in a circular knitting machine increases or decreases according to the diameter of the needle cylinder and the dial and the number of setting positions of the feeders also increases and decreases. The number of yarn feeders to be used with a needle cylinder of a given diameter is normally determined by equally dividing the circumference of the annular body by the space required for one yarn feeder to determine the width to be occupied by each arcuate part of each segment of the annular body and then making adjustments in widths of the segments to provide for increases or decreases in the number of yarn feeders. Thus, the number of segmental knitting cam support blocks required is determined by the given diameter of the needle cylinder to be employed. For example, in a circular knitting machine with a needle cylinder of 20 inches in diameter and with 41 yarn feeders, the annular body is first equally divided into 41 spaces. Then, if four feeders are to be carried by one segmental knitting cam support block, the annular body is divided into 10 segments, and the remaining one feeder [41-(4×10)=1]is provided on one of the segmental knitting cam support blocks. When the circular knitting machine has a needle cylinder of 19 inches in diameter and with 39 yarn feeders, the annular body is first divided into nine segments and the remaining three feeders [39-(4×9)=3]are supported on certain of the segmental knitting cam support blocks. Accordingly, the yarn feeders are equally supported on respective segmental knitting cam support blocks while any remaining yarn feeders are supported on other segmental knitting cam support blocks which are different in widthwise dimensions from the equally divided segmental knitting cam support blocks. In accordance with this conventional arrangement, circular knitting machines of the same kind, but having needle cylinders of different size, are manufactured and a manufacturer of tubular knitted fabric must have circular knitting machines in the mill which are of various nominal sizes (diameters) in order to produce tubular fabric of different given diameters. If it were possible to easily convert a given size of knitting machine to permit a limited range of needle cylinders of different diameters to be used on a given circular knitting machine, the number of knitting machines required by the knitting fabric manufacturer could be reduced and many advantages could be offered to the management of knitting machines and to economy. For this purpose, the size or diameter of the knitting machine could be changed by reducing the number of replacement parts to be applied to the knitting machine by the common use of setting positions of segmental knitting cam support blocks to be replaced. SUMMARY OF THE INVENTION It is an object of the present invention to provide conversion means for a circular knitting machine in which a plurality of sets of the main parts of the knitting unit, particularly segmental knitting cam support blocks and segmental knitting cam segments supported thereby, are provided to easily permit a limited range of needle cylinders and dials of different diameters to be used on a particular knitting machine. The illustrated knitting machine of the present invention is of the cylinder and dial type and is provided with knitting cam segments for actuating the knitting needles at each yarn feeder and these knitting cam segments are supported on sets of segmental knitting cam support blocks surrounding the needle cylinder and the dial. The widthwise dimensions between opposite sides of the segmental knitting cam support blocks of each set are varied so as to provide a certain number of segmental knitting cam support blocks dimensionally different from each other regardless of the particular size of the needle cylinder to be used in the knitting machine. The setting positions of the segmental knitting cam support blocks are common to various nominal sizes of needle cylinders and dials. Preferably, the number of yarn feeders supported on one segmental knitting cam support block is equivalent to an integral multiple of one pitch covered by one yarn feeder. The positions of the widthwise sides of adjoining segmental knitting cam support blocks are concentrated between setting positions of these segmental knitting cam support blocks when the nominal diameter of the needle cylinder and dial is varied. The common setting positions of the segmental knitting cam support blocks of each set permit the easy conversion of a machine with a given nominal size or diameter of needle cylinder and dial to a knitting machine with a different nominal size or diameter of the needle cylinder and dial. Thus, a particular knitting machine can be easily changed from one diameter to another diameter, within a limited range of needle cylinders of different diameters. Accordingly, replacement of the component parts to which the sets of segmental knitting cam support blocks are fixed becomes unnecessary and the frequency required to replace parts can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS Other objects and advantages will appear as the description proceeds when taken in connection with the accompanying drawings, in which FIG. 1 is a vertical sectional view through the needle cylinder and dial of a circular knitting machine with a different size cylinder and dial shown in dash and two-dot lines; FIG. 2 is a somewhat schematic plan view taken along the line 2--2 in FIG. 1 and illustrating the sets of segmental cylinder knitting cam support blocks surrounding the needle cylinder, the set of support blocks shown in continuous lines indicating the setting position corresponding to a nominal size needle cylinder of 20 inches, the set of support blocks shown in dotted lines corresponding to a nominal size needle cylinder of 19 inches, and the set of support blocks shown in dash and two-dot lines corresponding to a nominal size needle cylinder of 18 inches; and FIG. 3 is a somewhat schematic plan view taken along the line 3--3 in FIG. 1 and showing the sets of segmental dial knitting cam support blocks for actuating the dial needles, the set of support blocks shown in continuous lines illustrating the setting position corresponding to the nominal size dial of 20 inches, the set of support blocks shown in dotted lines corresponding to a nominal size dial of 19 inches, and the set of support blocks shown in dash and two-dot lines corresponding to the nominal size dial of 18 inches. DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG. 1, the conventional knitting machine includes a needle cylinder 1 with vertically extending needle grooves la formed on the outer periphery of the cylinder 1. A cylinder needle 2 is supported for vertical sliding movement in each of the needle grooves 1a and each cylinder needle 2 is provided with an operating butt 2a. Dial needles 3 operate in cooperation with the cylinder needles during knitting and are disposed horizontally and slide radially in grooves on a dial 4. The needle cylinder 1 is rotatably supported in a circular bed plate 5 having given inner and outer diameters. The lower end of the needle cylinder 1 is fixed to a driving gear 6 while the dial 4 is fixed on a needle dial hub 7 which rotates at the same speed as the gear 6 by the usual driving mechanism so that the cylinder 1 and the dial 4 rotate at the same speed. Knitting cam segments 9 surround the needle cylinder 1 and are operable on the butts 2a to vertically move the cylinder needles 2 to form stitch loops of yarns fed to the needles in the usual manner. The knitting cam segments 9 are supported on a set of segmental knitting cam support blocks 8. The segmental knitting cam support blocks 8 include inner peripheral surfaces supporting the knitting cam segments 9 thereon and in close proximity to the outer peripheral surface of the needle cylinder 1. The segmental knitting cam support blocks 8 are fixed on a circular cam retaining ring 10, as by bolts 8b. The circular cam retaining ring 10 includes an outer diameter adapted to closely fit within the inner diameter of the bed plate 5, and an inner peripheral circular edge of a given diameter surrounding the needle cylinder 1. Dial knitting cam segments 12 are provided for actuating and controlling the radial movement of the dial needles 3 and are fixed to the lower surface of a set of segmental dial knitting cam support blocks 11 spaced above the dial needle hub 7. The segmental knitting cam support blocks 11 are fixed to a dial cap hub 13, as by bolts 11b. The dash and two-dot line in FIG. 1 indicates respective positions of the needle cylinder 1, the segmental knitting cam support block 8, the driving gear 6, the dial 4, and segmental dial knitting cam support block 11, when the nominal size of the machine is changed. A change of the nominal size or diameter of the knitting machine requires a change of size of the component parts. As illustrated in FIG. 2, the conversion means of the present invention includes a plurality of sets of segmental cylinder knitting cam support blocks, broadly indicated at 8, and including individual segments S 1 -S 8 having outer curved peripheral edges 8a collectively defining a circle of a given diameter. Each segment has two bolts 8b, 8c which support the segmental cylinder knitting cam support blocks 8 for different nominal sizes. Each of the segmental cylinder knitting cam support blocks 8 of each set includes widthwise dimensions so that the individual segmental knitting cam support blocks form a complete circle around the needle cylinder when positioned adjacent to each other. Each of the segmental cylinder knitting cam support blocks 8 of each set includes curved inner peripheral edges collectively defining respective circles of different diameters to be used when needle cylinders of corresponding different diameters are to be used in the knitting machine. For example, the set of segments shown in solid lines in FIG. 2 include curved inner peripheral edges collectively defining a circle 20 to be used when a needle cylinder of a 20-inch diameter is to be used in the knitting machine. The curved inner peripheral edges of the set of segments shown in dotted lines in FIG. 2 define a circle indicated at 19 to be used when a needle cylinder of 19 inches is to be used in the knitting machine. The inner peripheral edges of the set of segments, shown in dash and two-dot lines in FIG. 2 and indicated at 18, are used when a needle cylinder of 18-inch diameter is to be used in the knitting machine. The circumferential space to be covered by one segment 8 of each set is determined on the basis that one space or pitch is equivalent to an integral multiple of one pitch covered by one yarn feeder. For example, as shown by the continuous line in FIG. 2, with a circular knitting machine with a 20-inch diameter needle cylinder there are 41 yarn feeders F provided. Five yarn feeders are provided on the first segment S 1 ; six yarn feeders for the second segment S 2 ; five feeders for the third segment S 3 ; four feeders for the fourth segment S 4 ; five feeders for the fifth segment S 5 ; five feeders for the sixth segment S 6 ; six feeders for the seventh segment S 7 ; and five feeders for the eighth segment S 8 . As shown by the dotted lines in FIG. 2, when constructing a circular knitting machine with a 19-inch needle cylinder size, one inch smaller than the 20-inch needle cylinder, with 39 feeders F', four yarn feeders are provided for the fourth segment S 4 whereas five feeders are provided for each of the other segments. As shown by the dash and two-dot lines in FIG. 2, when constructing a circular knitting machine with an 18-inch needle cylinder, one inch smaller than the previous machine, with 37 yarn feeders F", four yarn feeders are provided on the third, fourth and sixth segments S 3 , S 4 , and S 6 , and five feeders are provided on the other remaining segments. The arrangement of the sets of segmental dial knitting cam support blocks 11 is illustrated in FIG. 3, as illustrated by segments D 1 -D 8 . Each set of the segmental dial knitting cam support blocks includes outer curved peripheral edges collectively defining an outer circle 11a of a given diameter. Also, each segment of each set of the segmental dial knitting cam support blocks includes widthwise dimensions so that the individual segmental dial knitting cam support blocks collectively form a complete circle around the dial when positioned adjacent to each other. Each segment has two bolts 11b, 11c which are commonly usable for different nominal sizes. In the same manner as the segmental cylinder knitting cam support blocks 8, the segmental dial knitting cam support blocks 11 are provided in various sizes. When a 20-inch diameter cylinder is used, as shown in solid lines in FIG. 3, 41 feeders F are provided: five feeders on the first segment D 1 ; six feeders on the second segment D 2 ; five feeders on the third segment D 3 ; four feeders on the fourth segment D 4 ; five feeders on the fifth segment D 5 ; six feeders on the sixth segment D 6 ; six feeders on the seventh segment D 7 ; and five feeders on the eighth segment D 8 . When the knitting machine is adapted to use a 19-inch diameter cylinder, one inch smaller than the 20-inch cylinder, with 39 feeders F', as shown by the dotted lines in FIG. 3, four yarn feeders are provided on the fourth segment D 4 and five feeders are provided on each of the other segments. When the knitting machine is to be provided with an 18-inch diameter cylinder, one inch smaller than the previous machine, with 37 yarn feeders F", four yarn feeders are provided on the third, fourth and sixth segments D 3 , D 4 , and D 6 while five feeders are provided on the other segments. For machines of other needle cylinder sizes, within a limited range, the number and size of the segments is calculated in the same manner as set forth above and the setting positions are made commonly adaptable to all segments by unequal division of the annular body into eight sections. In this way, a certain number of unequal sized segments can be fixed to the cam retaining ring 10 or the dial cap hub 13. In addition to the specific examples set forth above, the concept of this invention is applicable to not only the cylinder and dial knitting cam support blocks but to the sinker cap for holding the sinker cams in a single knit circular machine, in electronic pattern knitting circular machines, and to the cam holder for holding the electromagnets as well as to other various annular bodies on the knitting machine. In accordance with the present invention, the setting positions of the segments of each set are made commonly adaptable to a variety of nominal sizes within a limited range of diameters by cutting a certain number of segments obtained by unequal division of the annular body, regardless of the nominal size to be used. In the drawings and specification there has been set forth the best mode presently contemplated for the practice of the present invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

Conversion of a circular knitting machine having a particular diameter of needle cylinder to a machine having a different diameter of needle cylinder is permitted within a limited range of sizes of needle cylinders. This conversion is made possible by providing a plurality of sets of segmental knitting cam support blocks which may be positioned around needle cylinders of different diameters to reduce the normal number of parts which must be replaced when changing a particular knitting machine from one size needle cylinder to another. The number of yarn feeders associated with each segmental knitting cam support blocks of each set is determined so that the number of yarn feeders supported by each segmental knitting cam support block is equivalent to an integral multiple of one pitch covered by one yarn feeder.

BACKGROUND OF THE INVENTION The present invention relates to a collapsible, portable, multi-use, inflatable device that can be used as a water sled, a water trailer, a floating platform (or raft) or a water trampoline. Personal watercraft are now very popular. However, such personal watercraft have very limited or no space for storing cargo. Consequently, if a user wishes to transport cargo using such a watercraft, it is necessary to make multiple trips. Water sleds have been used in the past as recreational vehicles for towing behind a boat. However, such water sleds have typically had no cargo transporting capability, but rather have been used solely as a recreational vehicle for carrying people and are comprised of inflatable tubes. A water sled that can be used to transport cargo is disclosed in U.S. Pat. No. 5,368,511. However, the device is not usable as a swim platform or trampoline because the support frame is not enclosed, and users may be hurt if they come into contact with the support frame. Water trampolines are known, in which a floating structure has a deformable mat that can be used as a trampoline. There is a need for a single, portable, multi-use inflatable device that can be used as a water sled, a water trailer, a floating water platform or as a water trampoline. SUMMARY OF THE INVENTION A steel frame assembly that attaches to a 5-chamber, side-by-side inflatable water sled. The frame assembly supports a surface area that consists of a cargo mat and a polypropylene trampoline mat with protective pads. The water sled is slightly modified and structurally reinforced to allow a frame to be attached. The frame assembly converts the water sled into a portable, multi-use product that can be towed behind a boat. A principle object and advantage of the present invention is that it converts a water sled into a water trailer that can be pulled behind a personal watercraft or any watercraft with sufficient pulling power. Another principle object and advantage of the present invention is that the water trailer allows the owner to carry cargo easily on the top of the cargo mat and allows the owner to tie off and secure the cargo to tie-down grommets provided on the mat. Another principle object and advantage of the present invention is that the water sled converts to a swim platform, or trampoline including attachable safety pads that protect the user from hitting the steel frame. Another principle object and advantage of the present invention is that it includes D-rings that allow the invention to be anchored to the bottom of a lake, creating a stable swim deck or water platform. Another principle object and advantage of the present invention is that the water platform can be used as a swimmers assist platform, a hunting platform, a portable water ski take-off platform or for any activity where a floating platform is needed. Another principle object and advantage of the present invention is that it can be used as a sun deck and is collapsible for storage or transportation. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side perspective view of the device as a water trailer. FIG. 2 is a top perspective view of the frame on top of the water sled shown in phantom outline. FIG. 3 is a front elevational view of the device converted to a swim platform or trampoline. FIG. 4 is similar to FIG. 1, with the trampoline mat added to further enclose the frame with the addition of a swim ladder, the device being anchored. FIG. 5 is a broken and cut away view of the frame showing the disassembly mechanism. FIG. 6 is a perspective view of the device used as a cargo trailer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The collapsible, multi-use water device is generally designated by numeral 10 and may be viewed in FIGS. 1-6. The device 10 generally comprises a multi-chambered inflatable water sled 12 , a stainless steel frame 34 capturing the water sled 12 , cargo mat 64 and a padded mat 78 . The details of the water sled 12 may be appreciated by viewing FIGS. 1-4 and 6 . The sled 12 has inflatable large tubes 14 with coned ends 16 , inner opposing support rings 18 , and outer anchor rings 18 are on the forward cone ends 16 of tubes 14 . In between the inflatable large tubes 14 is intermediate buoyancy tube 22 , also having coned ends 24 . Lateral stabilizing wings 26 extend outwardly from the large tubes 14 . The lateral stabilizing rope 28 connects the inner support rings 18 located frontwardly and rearwardly on the large tubes 14 to further capture intermediate buoyancy tube 28 and to prevent the inflatable large tubes 14 from separating away from each other in a downwardly and outwardly fashion. The tow or anchor rope 30 is secured to the outer anchor rings 20 and may be used to anchor the device 10 to the bottom of the lake or otherwise tow the device 10 with a self-propelled watercraft. The details of the stainless steel tubular frame 34 may be greatly appreciated by viewing all of the FIGS. 1-6. Steel frame 34 is suitably U-shaped when viewing from a front or rear view and is longitudinally linear front to back while retaining strength to permit the water device 10 to move through the water with minimal resistance. Steel frame 34 includes rigidifying top cross beams 35 , 36 and 37 with an optional fourth cross beam 37 shown in phantom in FIG. 2 . Cross beams 35 and 37 have intermediate depending tube buoyancy supports 38 , which rest upon intermediate buoyancy tube 22 . Stabilizing strut 39 extends from outermost top cross beams 35 and 37 to supports 38 to add strength to the overall frame 34 . Top longitudinal beams 40 are connected to the cross beams 35 , 36 and 37 suitably by welding. From the top longitudinal beams 40 are depending and opposing rectangular subframes 48 which capture the large tubes 14 . The subframes 42 include intermediate longitudinal members 44 and bottom longitudinal members 46 . The intermediate and bottom members 44 and 46 capture the lateral stabilizing wings 26 of the water sled 12 when the water sled is inflated with the steel frame 34 therearound. While it is known that the water sled 12 may be deflated and folded or rolled up for transportation, the steel frame 34 has frame joints 50 shown in FIGS. 2 and 5. The joints 50 are positioned intermediately in the top longitudinal beams 40 , intermediate longitudinal members 44 and bottom longitudinal members 46 . The frame joints 50 each have an elongate sleeve 52 with an aperture 54 therein. The sleeve 52 captures the opposing frame end 56 sufficiently to assure rigidity of the overall frame, while a spring-loaded securing button 60 locks into aperture 54 of sleeve 52 . Thus, steel frame structure 34 comprised of tubes, may be broken in half for easy transportation or storage. The cargo mat 64 of the water device 10 may best be viewed in FIGS. 1, 3 , 5 and 6 . The cargo mat 64 has peripheral grommets 66 and two opposing longitudinal sleeves 68 which capture the top longitudinal beams 40 clearly shown in FIGS. 1, 5 and 6 . Cargo flaps 70 extend laterally from the cargo mat 64 and suitably support gripping handles 72 as well as the previously disclosed grommet 66 . Inwardly and adjacent to the steel frame 34 on top of the cargo mat 64 is a rectangular hook and loop strip as will be appreciated later. The cargo flaps 70 may be lifted upwardly onto the mat 64 to further enclose cargo and to permit the cargo net or rope 76 to be interwoven with grommet 66 , as clearly depicted in FIG. 6 . The padded mat 78 permits the device 10 to be used as a sun deck, swim platform or trampoline. The underside of padded mat 78 has cooperating rectangular hook and loop strips 80 to match with the rectangular hook and loop strip 74 on the cargo mat 64 to secure the padded mat 78 to the cargo mat 64 . The padded mat 78 has extending frame pads 82 peripherally located therearound to cover all of the steel frame 34 . Handles 84 and ladder 86 may also be secured to the padded mat 78 , as is conventionally known. In use, the water device 10 may be used simply as a water sled 12 upon which people may sit and hold onto the handles shown in FIG. 2 (unnumbered) in phantom outline. Alternatively, the water sled 12 may be somewhat or completely deflated and the steel frame 34 placed thereover. Upon inflation of the sled 12 , the lateral stabilizing wings 26 pass through and in between intermediate and bottom longitudinal members 44 and 46 to capture the water sled 12 underneath the frame 34 . The depending intermediate two buoyancy supports 38 further secured by strut 39 rest upon intermediate buoyancy tube 22 to give the water device further support from below and when the device 10 is used as a trampoline. As may be appreciated, cargo may be loaded on top of the water device 10 and secured, as shown in FIG. 6, to be towed by a self-propelled watercraft. The padded mat 78 may be laid upon the cargo mat 64 and held securely by the hook and loop strips 74 and 80 with the extending frame pads 82 extending over the steel frame 34 . Padded mat 78 may also be secured to frame 34 . In this condition, the water device 10 may be used as a sun deck, swim platform or trampoline by young children. Handles 84 and ladder 86 may be attached to padded mat 78 to make the water device 10 more user friendly.

A steel frame assembly that attaches to a 5-chamber, side-by-side inflatable water sled. The frame assembly supports a surface area that consists of a cargo mat and a polypropylene trampoline mat with protective pads. The water sled is slightly modified and structurally reinforced to allow a frame to be attached. The frame assembly converts the water sled into a portable, multi-use product that can be towed behind a boat.

CROSS REFERENCES TO CO-PENDING APPLICATIONS None. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is for a support system, and more particularly, pertains to a cam style hub and strut system for use in portable and semi-permanent structures. The present invention can be used in any number of structures, including but not limited to, portable or semi-permanent structures, such as ice fishing houses, movie screens, road crew signs, boat covers, tents, medical tents, hunting blinds, photography blinds, portable garages, and the like. 2. Description of the Prior Art Portable or semi-permanent structures are popular and practical for many of the aforementioned applications. The shortcomings of the current art device centrally hubbed units lie in the impracticality of utilizing the proper amount of extra diagonal length between the rod or strut ends and the distance between corners of a panel. The diagonal distance between opposing strut ends must be sufficiently greater than the corresponding corner-to-corner measurement of the panel in order to hold the panel in place once the hub is forced through the center. When the struts used are of optimal length, the unit becomes very difficult to set up, and damage to the hub system or structure itself frequently occurs. Couple this with the fact that many optimal structural fabrics stretch and shrink when contacted with environmental conditions to which they are commonly exposed, for example, rain, high humidity, heat, sunlight, and the like, the optimal system then is one that can be adjustable. In systems utilizing fabrics prone to stretching or shrinking, the unit may be built so that the cam need only be engaged in conditions in which the fabric is found to be affected. This system couples ease of setup with the cam disengaged and application of the proper amount of pressure on the panel to hold the system in a fixed position with the cam engaged, utilizing either flexible or rigid struts depending upon the properties of the material used in the panel and the size of the panel. SUMMARY OF THE INVENTION The present invention incorporates a cam style hub and strut system with offset pivot points in the hub that when turned moves the opposing struts to a lineal orientation furthering the distance between the strut ends. This allows ease of setup partnered with the ability to apply a greater amount of diagonal force upon the panel in which they are installed, creating panels used in structures that were formerly prone to failure caused by (1) the forces exerted in erection, (2) changes in environmental conditions, (3) excessive wind or wind flap, specifically in wildlife concealment applications (wind flap equates to failure), (4) injury from sudden accidental collapse, and (5) inability to erect. The cam style hub also eliminates the need for excessive panel construction costs associated with current techniques incorporating elastic perimeters, no-stretch perimeters, spring-loaded strut end caps, and the use of various sizes of struts needed to match panel material weights and stretch properties. The framework of the cam need not go past 180 degrees and may incorporate a locking mechanism, if desired. The diagonal length of the struts is greater than the diagonal of the panel. The locking mechanism makes it possible to use same length struts if desired, meaning struts will not bow and the structure will stay up. According to one embodiment of the present invention, there is provided a cam style hub and strut system, including a centrally located rotatable hub having a plurality of positionable struts extending outwardly therefrom to engage the outer regions of a flexible panel of cloth, tent material, canvas, sheet plastic or the like. One significant aspect and feature of the present invention is a cam style hub and strut system having a centrally located rotatable hub which operates two or more struts outwardly. The cam style hub and strut system includes sockets which accommodate the ball ends of the outwardly extendable struts. The cam style hub and strut system incorporates over-the-center locks. Another significant aspect and feature of the present invention is a cam style hub and strut system incorporating capture detents to lock the struts in the extended position. Yet another significant aspect and feature of the present invention is a cam style hub and strut system having accommodational maneuvering channels, truncated slots and capture detents in which the struts can be positioned, maneuvered and locked or collapsed. A further significant aspect and feature of the present invention is a cam style hub and strut system in which the struts are collapsible when not in use. Having thus described one or more embodiments of the present invention, it is the principal objective hereof to provide a cam style hub and strut system. BRIEF DESCRIPTION OF THE DRAWINGS Other objects of the present invention and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein: FIG. 1 illustrates a cam style hub and strut system, the present invention, engaging a portable or semi-permanent panel; FIG. 2 illustrates an isometric view of the hub and the inboard ends of the struts; FIG. 3 illustrates a perspective and inverted bottom view of the hub; FIG. 4 illustrates an isometric view of the capture plate with the actuator handle rotated at an angle with respect to the capture plate to reveal the inwardly facing planar surfaces of the capture plate and the actuator handle; FIG. 5 illustrates a side view of the hub and an actuator strut end; FIG. 6 illustrates a bottom view of the hub; FIG. 7 illustrates a bottom view of the hub accommodating the inboard ends of a plurality of struts; FIG. 8 illustrates a bottom view of the hub rotated counterclockwise, as viewed from the bottom, to outwardly position the struts; FIG. 9 illustrates a side view of the cam style hub and strut system along line 9 — 9 of FIG. 8 having the struts locked in the extended position by the hub; and, FIG. 10 illustrates a side view of the cam style hub and strut system where the hub has been rotated clockwise to disengage and unlock the struts from the over-the-center lock mode and from the capture detents. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates a cam style hub and strut system 10 , the present invention, engaging a portable or semi-permanent panel 12 shown in dashed lines. Although only one cam style hub and strut system 10 is shown engaging one panel, it should be appreciated that a plurality of panels such as panel 12 can be incorporated in juxtaposition to form a portable or semi-permanent structure incorporating several of the cam style hub and strut systems 10 . The cam style hub and strut system 10 includes a cam style hub herein called the hub 14 preferably of Zytel or other suitable plastic, metal, or suitable material. A plurality of struts 16 a, 16 b, 16 c and 16 d extend forcibly and outwardly from the hub 14 to engage the corners of the panel 12 to stretch or otherwise suitably form or shape the panel 12 . Pockets 58 a - 58 d are sewn or glued onto ends of the panel 12 material for receiving the strut ends. In the alternative, any suitable panel fastening structure can be secured onto the ends of the struts by any suitable known process, such as glue, adhesives, lacing composed of string or thread, or even hook and loop materials. The struts 16 a - 16 d are of flexible or rigid construction such as, but not limited to, fiberglass, plastic, steel rod and the like. The panel fastening structure can be on the panel, the struts, or both. FIG. 2 illustrates an isometric view of the hub 14 and the inboard ends of the struts 16 a - 16 d . The hub 14 is a split and subsequently mated assembly having a configured actuator handle 18 and a configured capture plate 20 . The actuator handle 18 and the capture plate 20 secure over and about and capture the ball ends 22 a , 22 b , 22 c and 22 d of the struts 16 a , 16 b , 16 c and 16 d , respectively, which are shown for clarity exterior to the hub 14 . A plurality of accommodational maneuvering channels 24 , 26 , 28 and 30 are located and formed between the actuator handle 18 and the capture plate 20 . The accommodational maneuvering channels 24 , 26 , 28 and 30 are spaced at 90 degree intervals with respect to each other to intersect sockets 32 , 34 , 36 and 38 , respectively, within the hub 14 , as partially illustrated in this figure and as illustrated in FIG. 6 and other figures as required. Movement of the ball ends 22 a , 22 b , 22 c and 22 d of the struts 16 a , 16 b , 16 c and 16 d within the accommodational maneuvering channels 24 , 26 , 28 and 30 is best understood by further description of the accommodational maneuvering channels 24 , 26 , 28 and 30 . Accommodational maneuvering channel 24 , being in all respects similar to and having features and components similar to accommodational maneuvering channels 26 , 28 and 30 is now described. Reference is also made to FIGS. 4 and 6 wherein accommodational maneuvering channel 24 extends substantially horizontally within the hub 14 and is substantially V-shaped and, in the actuator handle 18 , includes a horizontally aligned planar surface 40 between an inwardly extending arced surface 42 and another inwardly extending arced surface 44 . The planar surface 40 and arced surfaces 42 and 44 form a contiguous surface which intersects an upper and partial socket portion 32 a . In the capture plate 20 a truncated slot 46 extends inwardly in juxtaposition with the arced surface 42 to intersect a lower and partial socket portion 32 b . Also intersecting the lower and partial socket portion 32 b is an inwardly extending arced surface 48 which juxtaposes the arced surface 44 of the actuator handle 18 . The arced surface 48 is slightly greater than 450 and the arced surface 44 is 45° which in combination forms an arc of just slightly more than 90° which provides for a low pressure capture detent 50 useful for snap-engagement of the strut 16 a within the capture detent 50 during operation of the invention. The ball end 22 a is captured during assembly of the actuator handle 18 and the capture plate 20 . With respect to the horizontal, the strut 16 a can be accommodated and maneuvered horizontally about the intersection of the ball end 22 a and the socket 32 . Horizontal movement of the strut 16 a is allowed along the planar surface 40 and between the arced surface 42 and the capture detent 50 . Capture of the strut 16 a within the capture detent 50 discourages horizontal movement and restricts vertical maneuvering of the strut 16 a . With respect to the vertical positioning of the strut 16 a such as for collapsing of the cam style hub and strut system 10 and associated panel 12 , the strut 16 a must be maneuvered and positioned out of the capture detent 50 and aligned to the arced surface 42 which also places the strut 16 a in alignment with the truncated slot 46 whereby the strut may be rotatingly positioned along the truncated slot 46 and maneuvered vertically, thereby placing the axis of the strut 16 a perpendicular to the hub 14 . FIG. 3 illustrates a perspective and inverted bottom view of the hub 14 . Illustrated in particular is the truncated slot 46 typical to other truncated slots in the invention. Also visible are the heads of a plurality of screws 52 a - 52 n which secure the capture plate 20 to the actuator handle 18 . Other securing processes can include gluing, adhesives, welding, snap-fit, etc. FIG. 4 illustrates an isometric view of the capture plate 20 with the actuator handle 18 rotated at an angle with respect to the capture plate 20 to reveal the inwardly facing planar surfaces 54 and 56 , respectively, of the capture plate 20 and the actuator handle 18 . Illustrated in particular is the upper and partial socket portion 32 a in the actuator handle 18 and the lower and partial socket portion 32 b in the capture plate 20 which in joined and mated combination form the socket 32 . In a similar fashion, planar surface 56 on the lower region of the actuator handle 18 aligns and mates to a corresponding planar surface 54 on the upper region of the capture plate 20 to additionally align upper and partial socket portions 34 a, 36 a and 38 a of the actuator handle 18 with the corresponding lower and partial socket portions 34 b, 36 b and 38 b of the capture plate 20 to form sockets 34 , 36 and 38 . FIG. 5 illustrates a side view of the hub 14 and an end of actuator strut 16 a , where all numerals correspond to those previously described. FIG. 6 illustrates a bottom view of the hub 14 , where all numerals correspond to those previously described. MODE OF OPERATION FIG. 7 illustrates a bottom view of the hub 14 accommodating the inboard ends of struts 16 a - 16 d . The outboard ends of the struts 16 a - 16 d extend to the end of a panel such as panel 12 shown in FIG. 1 and are secured or captured thereto or therein. The struts 16 a - 16 d are rotated, for purposes of illustration and example, to the fullest counterclockwise position about the respective ball ends 22 a - 22 d , and are limited in travel in a counterclockwise position by one side such as the arced surface 42 of the accommodational maneuvering channels 24 , 26 , 28 and 30 , respectively, and to also lie against the planar surfaces of the accommodational maneuvering channels 24 , 26 , 28 and 30 , such as planar surface 40 . In addition, the inboard strut ends of the struts 16 a - 16 d are also aligned to the truncated slots 46 . The position of the struts 16 a - 16 d is shown in the relaxed and non-actuated position and the hub 14 is also shown in the relaxed and non-actuated position. Also referenced in the drawing is distance D 1 , being the distance between the centers of the ball ends 22 a and 22 c in the unactuated position. FIG. 8 illustrates a bottom view of the hub 14 rotated counterclockwise, as viewed from the bottom, to outwardly position struts 16 a - 16 d and tighten an accompanying panel 12 . As the hub 14 is rotated counterclockwise about its center, the ball ends are likewise urged in a counterclockwise direction. At the same time a new distance D 2 between the ball ends 22 a and 22 c is created, that distance being larger than distance D 1 in the previous FIG. 7 . With respect to and comparison of the old distance D 1 and the new distance D 2 , it can be seen that the ball ends 22 a and 22 c (and ball ends 22 b and 22 d ) and thus the struts 16 a and 16 c (and the struts 16 b and 16 d ) are further distanced to create a new and increased distance from the outboard tips of the struts 16 a - 16 d which is applied to the outward reaches of the panel 12 . The struts 16 a - 16 d are locked by (1) snappingly engaging the capture detents 50 and, (2) over-the-center positioning of opposing strut set 16 a and 16 c and strut set 16 b and 16 d with relation to each other. At full counter-rotation of the hub 14 , the inboard portion of the strut 16 a and the remaining struts 16 b - 16 d align in the capture detents 50 , typical to the accommodational maneuvering channels 24 , 26 , 28 and 30 , to opposingly lock over-the-center and positionally fix the struts 16 a - 16 d with respect to the hub 14 and to each other. FIG. 9 illustrates a side view of the cam style hub and strut system 10 along line 9 — 9 of FIG. 8 having the struts 16 a - 16 d locked in the extended position by the hub 14 , where all numerals correspond to those elements previously described. Particularly noted is the strut 16 a which is captured by the capture detent 50 . The elasticity of the hub material is such that entry of and exit from the capture detents 50 by the struts 16 a - 16 d is accomplished with a nominal amount of rotational pressure as applied to the hub 14 for engagement or disengagement of the hub 14 with the struts 16 a - 16 d. FIG. 10 illustrates a side view of the cam style hub and strut system 10 where the hub 14 has been rotated clockwise to disengage and unlock the struts 16 a - 16 d from the over-the-center lock mode and from the capture detents 50 , where all numerals correspond to those elements previously described. The hub 14 can be rotated to the full clockwise position positioning the inboard ends of the struts 16 a - 16 d fully away from the capture detents 50 , thus aligning the inboard ends of the struts 16 a - 16 d to the opposing arced surfaces 42 at the ends of the accommodational maneuvering channels 24 , 26 , 28 and 30 which also places the inboard ends of the struts 16 a - 16 d in alignment with the truncated slots 46 . Positioning of the inboard ends of the struts 16 a - 16 d in the truncated slots 46 allows yet another positioning of the struts 16 a - 16 d in the vertical position, as shown, for collapsing of the struts 16 a - 16 d and the panel 12 attached thereto. Various modifications can be made to the present invention without departing from the apparent scope hereof.

A cam style hub and strut system for use in single panel fabric, cloth, or plastic units, or structures with an unlimited number of wall and/or roof panels. The purpose of the cam style hub is to compensate for certain fabric characteristics and to allow easier setup of structures containing flexible or rigid support struts connected to a central hub by lessening the distance of the diametrically opposing struts during assembly, and applying the force necessary to engage the self-supporting structure by engaging the cam, increasing the distance between the ends of the opposing struts. The amount the distance is increased can be dictated by materials used and the size of the panel. The hub may contain an optional “locking” feature activated when the hub cam is engaged for convenience and safety reasons. The principle can be used with any number of struts greater than one.

CROSS-REFERENCE TO RELATED APPLICATION This application is a continuation application of U.S. application Ser. No. 09/051,311, filed Jul. 27, 1998, now U.S. Pat. No. 6,491,703, which was the National Stage of International Application No. PCT/SE96/01269, filed Oct. 8, 1996 and published in the English language. FIELD OF THE INVENTION The invention relates to a surgical instrument and a method using same for treating female urinary incontinence. BACKGROUND OF THE INVENTION U.S. Pat. No. 5,112,344 discloses a surgical incontinence device and method, wherein the disclosed device includes a shank having a handle at one end thereof, and a curved needle-like element which is constructed to be connected with the shank to form a curved portion. WO-A-9606567, the content of which is hereby incorporated by reference herein, discloses a surgical incontinence device that allows for alleviating female urinary incontinence while restoring continence by attaching two curved needles to a tape that is intended to be permanently implanted into the tissue between the vaginal wall and the abdominal wall of a patient, thus strengthening the tissue required to restore the urinary continence. The method disclosed in WO-A-9606567 involves the steps of passing the tape into the tissue between the vaginal wall and the abdominal wall and leaving the tape permanently in the body, thereby providing reinforcement of the tissue that is required to restore urinary continence, either by the tape itself acting as an artificial ligament or by the development of fibrous tissue. BRIEF SUMMARY OF THE INVENTION The method of the present invention relates to treating female urinary incontinence and involves passing the first and second ends of a tape into a female patient's body and then positioning at least a portion of the tape between the vaginal wall and the urethra. After such positioning, the tape forms a supportive loop beneath the urethra. The ends of the tape are then extended over the patient's pubic bone and through her abdominal wall such that the ends of the tape extend outside of the patient's body. The position and tension of the supportive loop are adjusted to achieve a clinically acceptable degree of urinary continence. The ends of the tape may be passed into the patient's body via the vagina. The tape may be at least partially enclosed by a removable sheath, which is removed after the tape is positioned and adjusted. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be explained in more detail with reference to the accompanying drawings which disclose the surgical instrument according to the invention and wherein. FIG. 1 is a side view of the surgical instrument according to the invention, FIG. 2 is a plan view of the surgical instrument, FIG. 3 is an exploded side view of one of the needles and tape and shrinkage hose to be connected with said needle, FIG. 4 is a side view of the needle in FIG. 3 with the tape connected therewith, FIG. 5 is an enlarged fragmentary axial cross sectional view of a coupling of the instrument for connecting an exchangeable needle thereof, FIG. 6 is a side view of the two needles and a tape interconnecting said needles, FIGS. 7 to 13 illustrate diagrammatically several surgical steps of the method according to the invention, and FIG. 14 in the same way illustrates the final step of the method. DETAILED DESCRIPTION OF THE INVENTION In the following description, the same reference numerals have been used to describe the various features of the instrument of the present invention as were used in WO-A-9606567. To facilitate the following discussion, however, the order of the figures has been changed and the reference numerals used to describe the female urinary system have been altered. With reference to FIGS. 1-6 , the surgical instrument of the present invention comprises a cylindrical tubular shank 10 having at one end thereof a handle 11 . At the other end of the shank there is a socket 14 . A cylindrical shaft 15 (see FIGS. 2 and 5 ) is rotatably mounted in the shank and can be rotated manually by means of a knob 16 mounted to one end of the shaft. The other end of the shaft 15 forms a cylindrical portion 17 (see FIG. 5 ) of smaller outside diameter than the shaft, which joins a portion 18 having external threads, a smooth end portion 19 of further reduced diameter joining the threaded portion 18 , end portion 19 forming a guide pin at said other end of the shaft. Portions 18 and 19 are received in the portion of socket 14 projecting from the shank. The surgical instrument as described so far is in agreement with the instrument disclosed in WO-A-9606567 except that the end portion 14 ′ of socket 14 is flattened from opposite sides (see FIGS. 1 and 2 ), so that the cross section of said end portion is non-circular. The surgical instrument also includes an exchangeable and disposable needle 21 which at one end thereof is attached to the shank at one end of the needle and extends over substantially a quarter of a circle to the other, free end thereof in order to follow substantially the profile of the pubis between the vagina and the abdominal wall. The needle has uniform circular cross section and has a smooth, preferably polished outside surface. At the free end thereof the needle forms a point 22 by being terminated by a conical portion. For attachment of needle 21 to shank 10 the needle forms at said one end thereof a straight portion 30 which is cylindrical but has milled flat faces 31 (see FIG. 3 ) over that part of said portion 30 , extending from the adjacent end of the needle, which shall be received by socket portion 14 ′. The needle should be oriented in a predetermined rotational position in relation to the shank, and more particularly it should project at right angles to the plane of handle 11 . This rotational position is secured by the non-circular shape of socket portion 14 ′ and the end portion of the needle having the flat faces 31 , which fits into socket portion 14 ′. The end portion of the needle having the flat faces 31 joins the body of the needle over the conical portion 32 , which tapers towards a shoulder 33 (see FIG. 3 ). An axial blind hole extends from the end surface of the needle said hole having a threaded portion 23 and inwardly thereof a narrower, cylindrical portion 24 . Guide pin 19 is dimensioned to be guidingly received by said latter portion when the threaded portion 18 for attaching needle 21 to the rest of the surgical instrument is screwed into threaded portion 23 of the blind hole by rotating shaft 15 by manual rotation of knob 16 , the end surfaces of the shank and the needle being pressed against each other. Also this attachment is in agreement with that described in WO-A-9606567. When the method as described in WO-A-9606567 is practiced, two needles 21 A and 21 B (see FIG. 6 ) are each connected to each end of a tape 26 . According to the present invention, the tape 26 of the preferred embodiment comprises a mesh or netting forming openings of the order of 1 mm. A suitable material for the tape 26 is PROLENE®, a knitted polypropylene mesh having a thickness of 0.7 mm manufactured by Ethicon, Inc., Sommerville, N.J., USA. This material is approved by FDA in USA for implantation into the human body. The netting (tape) 26 preferably has a width of approximately 10 mm and is enclosed in a thin polyethylene sheath 34 which, in flattened condition, has substantially the same width as the tape 26 although a difference in width is shown in FIG. 2 in order to make the provision of the sheath 34 more clear. The length of the netting 26 should be approximately 400 mm. The netting 26 and the sheath 34 are interconnected by means of two rows 35 of stitching. The end portion of the sheath 34 is attached to the conical portion 32 (see FIG. 3 ) of the needle 21 by means of a suitable strong glue, and the interconnection of the needle 21 and sheath 34 is covered by a shrink hose 36 (see FIGS. 3 and 4 ) made of rubber, which extends from the shoulder 33 over the conical portion 32 and partly over the cylindrical end portion 30 of the needle 21 . The shrink hose 36 is substantially flush with the surface of the needle 21 at the shoulder 33 . By this arrangement the netting 26 is securely attached to the needle 21 . The purpose of sheath 34 is, above all, to facilitate the insertion of the netting 26 in the manner described in WO-A-9606567, i.e., when the netting 26 is pulled at the ends thereof from the vaginal wall to the abdominal skin and to avoid that rough edges of the netting irritate or damage the body tissues. When the tape has been positioned in the correct position as a sling around the urethra (as described hereinafter in connection with the method of the present invention shown in FIGS. 7-14 ) the polyethylene sheath 34 shall be removed, and in order to facilitate the removal the sheath 34 should be perforated at the longitudinal center thereof as indicated by a dot-and-dash line 37 in FIG. 6 , so that the two halves of the sheath 34 can be withdrawn from the body by pulling at the respective outer ends thereof, the halves being separated at the perforation under the influence of the pulling force. The purpose of the polyethylene sheath 34 is also to protect the netting 26 during attachment to the needles 21 A, 21 B and during handling before and during insertion into the body. The longitudinal center of the tape 26 and sheath 34 should be indicated by a visible colour mark 38 , (see FIG. 6 , so that the surgeon readily can see when the netting 26 is symmetrically located with reference to urethra during the surgery. The method of the present invention will now be described in detail with reference to FIGS. 7-14 . In FIGS. 7-14 , the relevant parts of the female lower abdomen are disclosed diagrammatically, the vagina being designated 40 , the vaginal wall 42 , the urinary bladder 44 , the urethra 46 , the pubic bone 48 , and the abdominal wall 50 . The first step of the surgery for implanting tape 26 is disclosed in FIG. 7 and comprises penetration of the vaginal wall 42 by needle 21 A a cut having first been made in said wall 42 , and, also penetration of the soft tissue at one side of urethra 46 , the needle 21 A then, according to FIG. 8 , being passed close to the back of the pubic bone 48 and then through the abdominal wall 50 above the pubic bone 48 . A cut can be done through the abdominal wall 50 for the passage of the needle 21 A therethrough, but if the needle 21 A is pointed, it may be sufficient to let the needle 21 A penetrate into the abdominal wall 50 , from the inside thereof, and to make a registering cut in the abdominal wall 50 on the outside thereof. The shank 10 of the instrument is now disconnected from needle 21 A, FIG. 9 , by rotating shaft 15 at knob 16 so that the threaded portion 18 of the shaft 15 is unscrewed from the threaded portion 23 in needle 21 A, the needle 21 A then being withdrawn from the abdominal wall 50 by means of forceps and the tape 26 being pulled into and through the tissue as illustrated in FIG. 10 . The other needle 21 B is now attached to the shank 10 , FIG. 11 , and is passed through a cut in the vaginal wall 42 to pass through the soft tissue at the other side of the urethra 46 . The needle 21 B is passed through the abdominal wall 50 (see FIG. 12 ) and then, after having been disconnected from the shank 10 , is withdrawn from the abdominal wall 50 (see FIG. 13 ), all in the same way as in the earlier procedure with the first needle 21 A. Tape 26 is now located at each side of urethra 46 as shown in FIG. 13 and is tightened with the loop formed by the tape 26 located on the inside surface of the vaginal wall 42 (see FIG. 14 ). The surplus of the tape 26 at the outside of the abdominal wall 50 is cut off. Then, the tape 26 is left as an implant in the body to form an artificial ligament attached to the abdominal wall 50 and providing the support for the urethra 46 as required in order to restore urinary continence. Another kind of tape 26 , which may be used in the method according to the present invention, can be more closely woven than the tape 26 mentioned above and can be of such material that the tape 26 , after a shorter or longer period, will be completely resorbed. By the development of fibroblast proliferation stimulated by the tape 26 the reinforcement of the tissue required in order to restore the urinary continence will be obtained.

The method of the present invention relates to treating female urinary incontinence and involves passing opposite ends of a tape into a female patient's body and then positioning at least a portion of the tape between the vaginal wall and the urethra, whereby the tape forms a supportive loop beneath the urethra. The ends of the tape are extended through the patient's abdominal wall and outside of the patient's body and then the position and tension of the supportive loop are adjusted to achieve a clinically acceptable degree of urinary continence.

The present invention relates generally to door or window closures or the like and more specifically to a closure assembly which includes a panel member which is releasable at least at its lower end wherein the panel member is connected with a blind frame or the like by means of at least one releasing arm. In assemblies of the type to which the present invention relates, it has been relatively easy to provide a closure assembly having a panel which is pivotable about its lower end in order to open the door or window of the closure. However, it is more difficult and structurally more complex to provide a panel arrangement wherein the movable panel or member can be released both at its lower end as well as at the upper end thereof. It is particularly difficult where the movable panel or window is releasable simultaneously at both its lower and upper ends. Often in structures of this type, the movable panel is brought from a closed position wherein it is usually in a locked state, into a tilted position wherein only the upper panel end is removed or separated from the upper edge of the frame within which the panel is installed. Thereafter, release of the lower end of the panel relative to the panel frame occurs whereby a lateral offsetting position of the panel is reached by moving the panel parallel to itself. Such a lateral offset position is useful for ventilation or it may operate in a preferred manner to effect the starting position for sliding of the panel along a fixed field. The latter may be an additional panel which is either firmly connected with the blind frame or is a part thereof or else may be movable in some manner. It may, for example constitute a turning panel or a cleaning rotary panel. If the panel which is releasable at its lower end can be displaced after it has been released or can be laterally offset parallel to itself, the support at the bottom of the panel will occur through rollers, shoes or the like which may be supported on a rail or similar member. For lateral offsetting of the panel parallel to itself, the lower panel end is moved crosswise to the longitudinal axis of such a rail whereby its lateral distance changes. This lateral distance which is generally increased may be bridged with the aid of a releasing arm or arms. Panels which are used in doors and particularly doors having two or more glass panes and whose height and width is on the order of a meter or more tend to be quite heavy. The weight is transmitted to a rail member through releasing arms and for simplification normally at least two releasing arms may be assumed to be in use. Consequently, not only the releasing arms, but also the frames or their corner connections will be under considerable load during releasing or opening movements of the panel as well as when it is in the released or open state. The present invention is therefore directed toward development of a releasable panel for a closure such as a window door or the like which is connected with a blind frame of the closure through at least one releasing arm in such a manner that in particular the panel and the releasing arm or arms can safely withstand the occurring stresses, particularly the weight of the panel when it is released at its bottom edge and in particular so that the lower panel corners may be relieved of weight stresses. SUMMARY OF THE INVENTION Briefly, the present invention may be defined as a panel assembly preferably for a door or window comprising a frame member having a panel member operatively connected therewith for movement between a closed position and opened positions, an angular housing mounted to said frame at the corners thereof and connected with at least two adjacent members of said panel and at least one releasing arm adapted to extend between said frame and said panel, said releasing arm being connected at its panel-side end with said angular housing. Thus, the invention provides an improved structural arrangement for a door window or the like wherein the lower edge of a laterally movable panel member may be supported in a more secure way particularly in view of the fact that the releasing arm which supports the panel and which is mounted between the panel and the frame will have the end thereof attached to the panel side mounted in a preferably angular housing which also operates to strengthen the frame itself as a result of being attached at the corners of the frame. Thus, the panel side suspension need not be adapted to the internal spacial parameters of the panel but only to those of the housing. With an appropriate design and attachment of the housing it is possible to strengthen the bearing aspects of the assembly particularly with respect to its suspension characteristics and to design it so that at the point of occurring weight greater strength is exhibited and possibly also wind pressure stresses can be readily absorbed even in the case of large and heavy window panels. By connecting the housing with both a vertical and a horizontal member of the movable panel at the corners thereof, the joinder of the two members is not loaded in the corner zone or is understressed to only a small degree with the stress being in any event smaller than would occur if each of the releasing arms at the panel side were articulated with only one of the two panel members or respectively with the lower horizontal panel member. Especially in the case of panels which are made of plastic sections, the two panel members are glued or welded together in each corner and this joint is especially sensitive. If, therefore, there is applied a load directly on the members, utilization of the angular housing connected with both members will necessarily lead to stress relief of the glued or welded joint. An additional factor resides in the fact that the housing additionally stiffens the corner of the panel. In accordance with a preferred embodiment of the invention the angular housing to which the releasing arm is attached is formed as a mounted housing and is connected with the fact of the panel directed toward the interior of the room where the assembly is used. Therefore, the cross-sectional conditions and also the cross-sectional forms of the panel members with respect to articulation of the releasing arms are not significantly limiting and it is possible to construct the housing to be of such a size, particularly with regard to its depth, that is its dimension normal to the plane of the panel, that a strong panel side suspension will have sufficient space provided therein. The latter, therefore, is not restricted by any chambers of the profile or section or restricted with regard to dimension which is basically too small as is often the case with prior art windows or doors. In accordance with a further feature of the invention it is provided that the panel members are reinforced at least in the corner zones with the angular housing of the releasing arm being connected both with the members and with the reinforcing element. Particularly, if the frame members are made of plastic sectional bars, it is preferable to provide a reinforcement at least in the zone of the corners, the reinforcement elements being inserted into chambers of the profile. Thereby, in the vicinity of the corner weld, thicker walls will be obtained providing an advantageous effect in the attachment of the releasing arm housing. With the aid of the attachment means of the housing the reinforcement elements can be simultaneously secured so as to be nonslideable. The latter increase in a known manner the rigidity of the profile. Forces are transmitted through the housing, which may be attached by means of screws or the like, to the reinforced zones and this will lead to lower stresses on the weld seams. In a further development of the invention, a thrust bearing, and particularly an axial ball bearing, is inserted between the housing of the releasing arm and the panel side end of the arm. This thrust bearing may, on the one hand, absorb substantial force and is on the other hand outstanding for an extremely low resistance in turning. Besides, such bearings have relatively small diameters. In accordance with a further developement of the invention, the axial ball bearing is traversed by a bearing pin having a lower end which is nonrotatively retained in the panel side end of the releasing arm and whose part thereabove is mounted in at least one, and preferably two, radial bearings in the housing. The bearing pin exerts a motion relative to the housing and for compactness it is advantageous to provide a radial sliding bearing without an inner race; that is to provide rolling bodies which roll directly on the surface of the bearing pin. The radial bearing or bearings of the pin are preferably needle bearings. In accordance with a further embodiment of the invention, the radial bearing or bearings, and the axial bearing are secured in a bearing bushing which is retained in the housing so as to be adjustable at least in the vertical direction. Within an intended adjustment range, it is possible to simply align the panel relative to the blind frame or the like in the corner zone of the respective releasing arm. It is particularly advantageous in this connection, if the bearing bushing is adustable by means of a threaded connection and preferably adapted to be fixed by means of a setscrew or lock nut. The bearing bushing may be screwed in or out to a greater or lesser depth in order thereby to achieve raising or lowering of the respective corner of the panel. The adjusting device may appropriately include screw threaded means which are eccentric to the axis of the pin at the bearing bushing so that in addition to height adjustment there may also be accomplished a crosswise adjustment relative to the plane of the panel. Alternatively, or in addition to this crosswise adjustment, and particularly with regard to application of the panel against the blind frmae, there may be provided additional means to enable such adjustment. In a further development of the invention, the upper end of the bearing pin traverses an inner collar at the upper end of the bearing bushing and the outwardly projecting end piece is retained in the axial direction by means of securing element. The latter may, for example, comprise a conventional split ring or the like. Furthermore, it is considered advantageous if the frame side end of the releasing arm is rotatably mounted in a carriage, shoe or the like so that after the releasable panel has been moved to its laterally offset position it may be slidably moved to one side in order that the opening which is closed by the panel may be further uncovered. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the ivnention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated and described a preferred embodiment of the invention. DESCRIPTION OF THE DRAWINGS In the drawings: FIG. 1 is a front view of a panel assembly in accordance with the invention showing a panel member mounted in a blind frame; FIG. 2 is a side view showing the panel member tilted relative to the blind frame; FIG. 3 is a side view showing the panel member laterally offset; FIG. 4 is a perspective view showing in greater detail a part of a corner assembly of the device shown in FIG. 1; and FIG. 5 is a sectional view taken through the line V--V of FIG. 4 shown on a larger scale. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings and particularly to FIGS. 1, 2, and 3 there is shown a frame assembly in accordance with the present invention which is particularly useful in connection with door windows or the like. The assembly shown in FIGS. 1-3 includes a blind frame 1 and a panel 2 which is adapted to be tilted about its lower horizontal axis relative to the frame 1, as shown in FIG. 2. In addition to being tiltable about its lower axis, the panel 2 is also capable of being laterally offset relative to the panel 1 and is movable in a plane parallel to itself to the lateral offset position shown in FIG. 3. In addition, with the panel member 2 in the lateral offset position shown in FIG. 3, the member 2 may also be slidably moved in the direction of the arrow 3 so as to be placed in front of an area 4 so that the area which is normally covered by the panel 2 will be free to permit passage or movement therethrough. FIG. 2 shows the panel 2 in its tilted position pivoted about a lower horizontal axis. The upper edge or end of the panel 2 is then supported by means of a pair of scissor type release levers 5 and 6 or similar device. In the parallel offset position shown in FIG. 3, the lower end of the panel 2 is moved outwardly from the frame 1 and is supported by at least one, and preferably two, releasing arms 7 which extend between the frame 1 and the panel 2 or respectively, through a rail 8 attached thereto. This support is effected with two carriages 9 and 10 each having two rollers 11 and 12. The area 4 may comprise a panel which is preferably fixed or firmly connected with the blind frame 1 or integrally formed therewith or it may be comprised of a member which may for example be a rotatable panel to allow cleaning thereof. Tilting of the panel, and at least unlocking thereof and movement to a tilt readiness position, is achieved through an appropriate fitting. Essential components of such a fitting are a gear 13 which is actuated by means of an actuating element 14, drive rods 15 on the closure side being adapted to be shifted upwardly and downwardly by the gear 13. The rods are coupled through corner bends with additional horizontal drive rods and a second vertical drive rod. The releasing scissor levers 5 and 6 may at least be unlocked by these drive rods but they may also be actuated so that for example through a quarter turn of the actuating element 14 there will be brought about through the releasing scissor levers 5 and 6 tilting of the panel 2 (as shown in FIG. 2). If the releasing scissor levers are not controlled in this manner, the panel 2 may be pulled outwardly manually into the tilt position after a quarter turn of the actuating element 14. Analagous operation is also possible with an unlocking element (not shown) at the lower panel end if after a further rotation of the actuating element 14 the unlocking element is pulled out with the aid of the actuating element. As has been stated, the lower panel end is connected with the blind frame 1 by means of at least one, and preferably two, releasing arms 7 with the interposition of the rail 8. As a result, the entire panel weight is transmitted by these releasing arms to the rail and, if the latter is firmly connected with the lower frame member, the weight is also transmitted to the frame member. Each releasing arm is rotatably articulated both at the panel and at its carriage 9, 10 or the like. In FIG. 5 there is shown on an enlarged scale the connection at the panel side of the releasing arm 7 and the bearing thereof. An essential component part of this panel side bearing of the arm 7 is a bearing pin 17. The bearing pin 17 is nonrotatively retained in a seat 18 of the panel side end 19 of the releasing arm 7. On the panel side end 19 of the arm 7 there rests the lower race of an axial thrust bearing 22, which lower race is traversed by the bearing pin 17 and is nonrotatively connected therewith. The bearing pin 17 further traverses a lower needle bearing 20 and an upper needle bearing 21. The needles of these two bearings roll of directly on the surface of the bearing pin 17. Both these two needle bearings and the axial thrust bearing 22 are contained in a bearing bushing 23. It should be understood that the three bearings shown and described are intended as examples of the type of bearing means which may be utilized and in place of the needle bearings there may, of course, be utilized other radial rolling bearings of known structure. Additionally, instead of an axial ball bearing, an axial thrust bearing or other known structure can be utilized. However, the three types of bearings shown are preferred in that they exhibit the special feature of a relatively compact construction. The bearing bushing 23 has, at its upper end when in the installed position, an outer collar having a male thread 24. The thread 24 is connected with a female thread of an angular housing 25 of the releasing arm as seen especially in FIG. 4, the angular housing 25 being discussed in greater detail hereinafter. At the lower end of the bearing bushing 23 there is merely formed a guide collar 26 which, if necessary, may also be provided with a male thread which may then be screwed into a corresponding counterthread at the lower end of the housing 25. It will be readily seen that by screwing the bearing bushing 23 to a greater or lesser distance in the direction of arrow 27, or by screwing out in the opposite direction, there may be effected by means of the threaded connection of the housing 25 and bearing bushing 23 a vertical adjustment of the respective panel corner relative to the associated corner of the blind frame 1. In a manner not shown in detail, the male thread 24 may be offset eccentrically relative to the geometric axis 28 of the bearing pin 17 or, respectively, relative to this bearing (for example perpendicular to the plane of FIG. 5) so that in addition to the vertical adjustment of the panel corner they may also be provided an adjustment in the direction of the double arrow 29. To facilitate rotation of the bearing bushing 23, a polygonal and preferably a square member 30 is formed at its upper end. It is sufficient to provide two parallel wrench surfaces at this point and to secure the adjusted position of the bearing bushing relative to the housing 25 a setscrew 31 is provided which is radially adjustable as seen in FIG. 5. The housing 25 which accommodates the panel side end 19 of the releasing arm 7 is formed with a basically angular or right angled shape, as seen best in FIG. 4. The housing 25 is attached to the face 32 of the panel member 2, the face 32 being the side of the panel member 2 which faces into the interior of a room or enclosure in which the panel assembly is utilized. This arrangement has the advantage that the panel may be easier to manufacture from sectional shapes which may be also used for other windows or doors. Particularly, it may be provided that the panel is made from plastic sections which are welded or joined in a known manner at the corners thereof. The annular housing 25 is attached is attached to the panel face 32 by screws 33 and the housing 25 is also attached to a horizontal member of the panel 2 by similar screws 33, as seen in FIG. 4. By attaching the annular housing 25 in the manner shown to both the vertical and horizontal members of the panel 2 by means of attachments such as the screws 33 there may be achieved not only a stiffening of the respective lower corner of the panel 2 but at the same time also substantial stress relief of the weld seam or other connecting means joining the vertical and horizontal panel members at the corner at which the housing 25 is connected. In this regard it would be appropriate to reinforce the sections by reinforcement elements 34 which may, for example, comprise inserted tubular rods or the like and these reinforcement elements may also be supported or connected at the same time by the screws 33 which attach the housing 25. The bearing pin 17 is retained at its upper end by means of a split ring 35 or similar securing element at the upper end of the bearing bushing 23. Additionally, the two carriages 9 and 10 are coupled in the sliding direction by means of a rigid, rod type element 36. No recesses are necessary on the panel of the releasing arms of the housing 25. The fitting is easy to install and it may be centered through stop lugs or the like on the panel. Due to the favorable suspension characteristics of the panel through the releasing arms, essentially only frictional forces will occur during pivoting of the lower panel end which will be minimal despite potentially substantial weight of the panel. Thus, from the foregoing, it will be seen that the present invention provides a panel assembly wherein a panel 2 may be mounted on a frame 1 by means of releasing arms 7 so that the panel can be released at its upper end so that it may be brought into a tilted position with the panel also being capable of lateral offset movement parallel to itself, the panel being supported by at least one, and preferably two, of such releasing arms. The releasing arms 7 are associated at the two lower corners of the panel 2 upon a rail which is connected in a preferred manner with a lower horizontal member of the blind frame 1. Accordingly, the releasing arms 7 are rotatably articulated both at a carriage, such as the carriage 9, as well as at the panel 2. The panel side end 19 of each of the releasing arms 7 is mounted in a housing 25 which is preferably a housing mounted on a face 32 of the panel which faces inwardly of a room or enclosure. The attachment of the housing 25 is effected by means of screws with both a vertical and a horizontal member of the panel so that the lower corners of the panel may be reinforced while at the same time providing for appropriate articulated attachment of the releasing arms 7. As a result, welded or glued connection means at the corners of the panel which connect together the vertical and horizontal members thereof will be relieved of stress at the corner zone while at the same time providing a stiffening for the corner of the panel by means of the sturdy mounted housing. Essential features of the panel side releasing arm bearing are a bearing pin and a bearing bushing between which two radial bearings, preferably needle bearings, are inserted. An axial thrust bearing between the housing 25, or respectively between the bearing bushing adjustably retained therein and the panel side end 19 of the bearing arm 7 will as a rule absorb the comparatively high weight of the panel with the panel thus being able to be laterally offset parallel to itself and also capable of sliding movement. While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

A panel assembly for a door or window including a generally quadrilateral frame member having a panel member operatively connected therewith for movement between a closed position and opened positions wherein the frame member is either tilted about one edge thereof or moved laterally offset parallel to itself. Latch means provided between the panel member and the quadrilateral frame include at least one releasing arm and an angular housing, with the angular housing being connected at a corner of the panel member with two adjacent members thereof and with the releasing arm having a panel-side end at which the releasing arm is connected with the angular housing.

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority benefits under Title 35, Unites States Code, Section 119(a)-(d) or Section 365(b) from EP 07105662.6, filed on Apr. 4, 2007, by Nicholas O'Leary and John Mark Clifton, and entitled “APPARATUS AND METHOD FOR SWITCH ZONING”, which application is incorporated herein by reference in its entirety. BACKGROUND 1. Field The disclosure relates to a technology for controlling storage systems, and in particular to a technology for rules-based zoning of a storage networking switch. 2. Background A fibre channel network makes use of zoning to restrict communication between devices. This is typically done with the switch hardware that comprises the network infrastructure, or fabric. The basics of fabric zoning in a fibre channel network are described in U.S. Pat. No. 6,765,919, entitled “Method and system for creating and implementing zones within a fibre channel system”. SUMMARY OF THE PREFERRED EMBODIMENTS Certain embodiments accordingly provide, in a first aspect, an apparatus for assigning a device to a network zone, comprising: a switch component operable to receive an attachment request, port and device name data and device operating characteristics data from said device; and a rules engine operable to acquire said device operating characteristics data from said switch component; said rules engine being operable to apply rules logic to said device operating characteristics data to select a zone for said device. Preferably, said rules engine is further operable to apply said rules logic to said port and device name data. Preferably, said network zone is a network zone of a fibre channel network. Preferably, said device operating characteristics data comprises one of device type data or device vendor identification data. Preferably, said network comprises a storage area network. Preferably, said device operating characteristics data comprises a target/initiator status for the device. In a second aspect, there is provided by certain embodiments a method for assigning a device to a network zone, comprising the steps of: receiving, by a switch component, an attachment request, port and device name data and device operating characteristics data from said device; and acquiring said device operating characteristics data by a rules engine from said switch component; applying, by said rules engine, rules logic to said device operating characteristics data to select a zone for said device. Preferably, said rules engine is further operable to apply said rules logic to said port and device name data. Preferably, said network zone is a network zone of a fibre channel network. Preferably, said device operating characteristics data comprises one of device type data or device vendor identification data. Preferably, said network comprises a storage area network. Preferably, said device operating characteristics data comprises a target/initiator status for the device. In a third aspect, there is provided a data carrier having functional data thereon, said functional data comprising functional computer data structures to, when loaded into a computer system and operated upon thereby, enable said computer system to perform all the steps of a method according to the second aspect. In a fourth aspect, there is provided a computer program comprising computer program code to, when loaded into a computer system and executed thereon, cause said computer system to perform all the steps of a method according to the second aspect. BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment will now be described, by way of example only, with reference to the accompanying drawing figures, in which: FIG. 1 shows in schematic form an arrangement of apparatus in accordance with the prior art; FIG. 2 shows in schematic form an arrangement of apparatus in accordance with a preferred embodiment; and FIG. 3 shows in flowchart form one method or one logic arrangement in which a method of operation according to a preferred embodiment may be implemented DETAILED DESCRIPTION Preferred embodiments contemplate a technology for controlling fibre-channel systems, and in particular for providing rules-based zoning of a fibre-channel fabric switch. With reference to the disclosure of U.S. Pat. No. 6,765,919 and FIG. 1 of the present application, a fibre channel network communication system comprises a fabric 104 and a plurality of devices 106 , 108 , 110 . Fabric 104 is coupled to the various devices 106 , 108 , 110 , and acts as a switching network to allow devices to communicate with each other. Fabric 104 consists of one or more switches. Devices 106 , 108 , 110 may be any type of device, such as a computer or a peripheral, and are coupled to the fabric 104 using a point-to-point topology. Fabric 104 is also coupled to loop 112 . Loop 112 includes a hub 114 and devices 116 , 118 , 120 , which are coupled in a loop topology. In FIG. 1 , the fibre channel system includes two zones 100 and 102 . Zone 100 contains device 106 and device 108 . Zone 102 contains device 110 and loop 112 . Devices within the same zone may communicate with each other. Thus, for example, devices 106 and 108 may communicate with each other because they are both members of zone 100 . Likewise, device 110 and loop 112 may communicate with each other because they are both members of zone 102 . However, device 110 cannot communicate with device 106 because device 110 and device 106 are not members of a common zone. Similarly, device 110 cannot communicate with device 108 ; and loop 112 cannot communicate with either device 106 or device 108 . Zones are created that specify logical groups of devices that may communicate with one another. There are two techniques widely used today to configure the zone: 1) Port Zoning; and 2) World Wide Port Name (WWPN) Zoning. In Port Zoning, the ports of each switch are used to describe the zone. Any device that is then plugged into a port becomes a member of the zones that port is in. In WWPN Zoning, each device on the network (such as a storage area network, or SAN) has a globally-unique World-wide Port Number. Zones are defined as groups of WWPNs, so that it does not matter where in the fabric the device is physically connected. Port zoning has the advantage that one is able to physically group ports together for particular purposes. However it does not easily allow for expansion when all of the ports are used and it requires careful planning before the network is implemented. It can also easily lead to misconfigurations where the wrong device is plugged into a particular port. WWPN Zoning has the advantage that one is able to connect a device to the fabric anywhere. However one needs to know the WWPNs before one can connect a device to the fabric. It would thus be desirable to have a technology for controlling fibre channel systems and, in particular, a technology for more effective and less error-prone zoning of a fibre-channel fabric switch. A preferred embodiment is suitably implemented in a fibre channel network system, and more particularly in a storage networking system, such as a SAN, employing switching technologies for the fabric infrastructure. The following describes the sequence of events in a system as illustrated in FIG. 1 when a device connects to a fibre channel network: 1. Device plugs in 2. Device sends a Fabric Login (FLOGI) frame to the switch; the switch now knows WWPN/WWNN (World Wide Node Name) information about device 3. Switch logs into the device using an FC2login frame 4. Device accepts the FC2login 5. Switch logs into device using an FC4login frame 6. Device accepts the FC4login 7. Switch sends SCSI (Small Computer System Interface) inquiries to determine further information about the device 8. Switch logs out of the device. As can be seen in the sequence above, the switch has information concerning the WWPN and WWNN of the device, which information can be used in WWPN zoning, as in the prior art. The switch also has port information, which can be used for port zoning, as in the prior art. However, the switch also has available to it the SCSI information that can be acquired during step 7, and the preferred embodiments are operable to use this additional information advantageously to assist in assigning the device to a zone. According to the preferred embodiments, a user is able to configure rules on the switch to determine what zoning is applied to a device. The rules may take the form: If [CONDITION] then [RESULT] where CONDITION represents a logic statement regarding the properties of a device, and RESULT represents what action the switch should take with this device. It will be clear to one of ordinary skill in the art that any of the known logical operators (AND, OR, XOR etc.) may also be used in constructing rules logic statements according to the various embodiments. The properties available for inclusion in the CONDITION comprise those that are available from the SCSI inquiry data, including but not limited to: device type; vendor information; and target/initiator status. As will be clear to one of ordinary skill in the art, the characteristics may also include device identification data, such as WWPN/WWNN information, and port identification information. Both of these may be used in addition to the device operating characteristics data by a rules engine according to the preferred embodiment. The uses of the values available for RESULT include, but are not limited to: automatically creating zones that include the device and other devices that meet further defined conditions; automatically adding the device to existing zones; or isolating the device so it is unable to connect to anything else. The preferred embodiments thus allow for a plug-and-play type of mechanism for use within a fibre-channel network. A user is able to define sets of zoning rules that can be applied whenever a device is connected to the network to determine what zones the device should be a member of. Turning to FIG. 2 , which shows an apparatus in accordance with one preferred embodiment, there is shown a system according to FIG. 1 , but in which fabric 104 is shown to contain switch 122 and, additionally, rules engine 124 . Rules engine 124 is operable in conjunction with switch 122 and user input means 126 to construct zoning rules (as exemplified above) for devices that attach to fabric 104 . In FIG. 2 , new device 128 has attached to fabric 104 by means of switch 122 , and rules engine 124 has applied rules associated with switch 122 according to user input from user input means 126 . In this example, as a result of the application of the rules, new device 128 has been assigned to zone 100 . The general concept of rules engines is well known in the art, and needs no further explanation here. The preferred embodiment in the form of an apparatus or arrangement of apparatus thus advantageously addresses the problem of providing a technology for controlling fibre-channel systems, such as storage networking systems, and in particular for providing rules-based zoning of a storage networking switch. Turning now to FIG. 3 , there are shown in flowchart form the steps of a method or logic arrangement according to a preferred embodiment. In FIG. 3 , the method or logic arrangement includes steps beginning at START step 200 . At step 202 , a user uses the input device 126 in conjunction with rules engine 124 to create zoning rules as described above. At step 204 , a new device (for example, device 128 ) plugs in to the fabric and sends an FLOGI frame to the switch with the WWPN/WWNN information about itself. At step 206 the switch logs into the device using an FC2login frame, and at step 208 , the device accepts the FC2login. At step 210 , the switch logs into the device using an FC4login frame, and at step 212 , the device accepts the FC4login. The switch sends SCSI inquiries to determine further information about the device at step 214 , and at step 216 , the switch receives the SCSI response or responses. At step 218 , the switch is free to log out of the device. Meanwhile, at step 220 , the switch has called the rules engine with the information from the SCSI response or responses, and the rules engine applies the rules to the SCSI information at step 222 in order to assign the device to a zone according to the rules it has been given. At step 224 , the system continues operation. The preferred embodiment in the form of a method or logic arrangement thus advantageously addresses the problem of providing a technology for controlling storage systems, and in particular for providing rules-based zoning of a storage networking switch. A system according to the preferred embodiment has the advantage of WWPN zoning in which a device is able to connect to any point in the fabric, but without the disadvantage of needing to know the specific WWPNs ahead of time. It is also advantageous in allowing the user to use information beyond the port and WWPN to determine the zoning. Unlike the zoning techniques of the prior art, the embodiments make use of the extended information that is available to the switch, rather than just the port number and WWPN. Using this extended information to provide sets of user-selectable rules, the zoning can become much more dynamic. Some examples of such rules are: all host/initiator systems to be zoned in with a particular storage device; all storage devices that identify themselves as IBM DS6000 to be zoned in with all devices that identify themselves as the IBM SAN Volume Controller; and all devices with an ‘Emulex’ Host Bus adapter that are identified as host/initiator systems to be zoned in individual zones with a particular storage device. It will be clear to one of ordinary skill in the art that all or part of the method of the preferred embodiments may suitably and usefully be embodied in a logic apparatus, or a plurality of logic apparatus, comprising logic elements arranged to perform the steps of the method and that such logic elements may comprise hardware components, firmware components or a combination thereof. It will be equally clear to one of skill in the art that all or part of a logic arrangement according to the preferred embodiments may suitably be embodied in a logic apparatus comprising logic elements to perform the steps of the method, and that such logic elements may comprise components such as logic gates in, for example a programmable logic array or application-specific integrated circuit. Such a logic arrangement may further be embodied in enabling elements for temporarily or permanently establishing logic structures in such an array or circuit using, for example, a virtual hardware descriptor language, which may be stored and transmitted using fixed or transmittable carrier media. It will be appreciated that the method and arrangement described above may also suitably be carried out fully or partially in software running on one or more processors (not shown in the figures), and that the software may be provided in the form of one or more computer program elements carried on any suitable data-carrier (also not shown in the figures) such as a magnetic or optical disk or the like. Channels for the transmission of data may likewise comprise storage media of all descriptions as well as signal-carrying media, such as wired or wireless signal-carrying media. The present embodiments may further suitably be embodied as a computer program product for use with a computer system. Such an implementation may comprise a series of computer-readable instructions either fixed on a tangible medium, such as a computer readable medium, for example, diskette, CD-ROM, ROM, or hard disk, or transmittable to a computer system, via a modem or other interface device, over either a tangible medium, including but not limited to optical or analogue communications lines, or intangibly using wireless techniques, including but not limited to microwave, infrared or other transmission techniques. The series of computer readable instructions embodies all or part of the functionality previously described herein. Those skilled in the art will appreciate that such computer readable instructions can be written in a number of programming languages for use with many computer architectures or operating systems. Further, such instructions may be stored using any memory technology, present or future, including but not limited to, semiconductor, magnetic, or optical, or transmitted using any communications technology, present or future, including but not limited to optical, infrared, or microwave. It is contemplated that such a computer program product may be distributed as a removable medium with accompanying printed or electronic documentation, for example, shrink-wrapped software, pre-loaded with a computer system, for example, on a system ROM or fixed disk, or distributed from a server or electronic bulletin board over a network, for example, the Internet or World Wide Web. In an alternative, the preferred embodiment may be realized in the form of a computer implemented method of deploying a service comprising steps of deploying computer program code operable to, when deployed into a computer infrastructure and executed thereon, cause said computer infrastructure to perform all the steps of the method. In a further alternative, the preferred embodiment may be realized in the form of a data carrier having functional data thereon, said functional data comprising functional computer data structures to, when loaded into a computer system and operated upon thereby, enable said computer system to perform all the steps of the method. It will be clear to one skilled in the art that many improvements and modifications can be made to the foregoing exemplary embodiments.

An apparatus for assigning a device to a network zone comprises a switch component operable to receive an attachment request, port and device name data and device operating characteristics data from the device; and a rules engine operable to acquire the device operating characteristics data from the switch component; the rules engine being operable to apply rules logic to the device operating characteristics data to select a zone for the device. The rules engine may be further operable to apply the rules logic to the port and device name data. The network zone may be a network zone of a fiber channel network.

RELATED APPLICATION [0001] The present application is a continuation of U.S. patent application Ser. No. 14/138,045, filed 21 Dec. 2013, which claims priority to U.S. provisional patent app. No. 61/745,383 filed 21 Dec. 2012, each of which is incorporated herein by reference in its entirety. BACKGROUND [0002] 1. Field of the Invention [0003] The present invention is generally related to telestration for remote video collaboration with streaming imagery and is more specifically related to enhancing a remote operator's ability to annotate and interact with streaming imagery in a realistic, yet virtualized manner through simulating movement and reaction of the streaming imagery. [0004] 2. Related Art [0005] Industries that develop, manufacturer, and maintain complex products often find an insufficient number of employees with extensive training and experience to meet demand. This is particularly relevant as businesses become more geographically diverse. It is inefficient (and sometime physically impossible) to deploy an expert “into the field” on every occasion at a moment's notice. Rather, companies typically deploy technicians with relative degrees of experience who collaborate with the expert remotely. For example, a multi-national aerospace company might have local technicians in an Italian production plant conferring with senior designers in the United States regarding the fabrication concerns for a specialized airframe. Similarly, technicians on an ocean oil rig may consult with shore side experts to address problems with specialized drilling machinery. Traditionally, video monitoring, as described in previous art, has been instrumental in achieving this collaboration. [0006] Conventional tele-monitoring (aka teleconferencing) allows real-time audio and video tele-collaboration to improve education, training, and performance in many fields. Current collaboration methods include telestration, which can be performed either locally or remotely to identify regions of interest within the video images. For example, television personalities routinely annotate video of live or replayed video broadcasts to highlight their commentary. Similarly, flight engineers can remotely inspect possible damage to space vehicles using telestrated, high-definition images of the equipment while it is still in orbit. In short, expert know-how can be maintained at a centralized location while being mobilized anywhere at a moment's notice. [0007] Current telestration techniques, as defined in prior art, primarily display freehand and other two-dimensional drawings over a video image or series of images. However, true collaboration is better achieved if the remote expert can demonstrate information through movement and manipulation of the images. In this invention, a computer simulation of the objects within the video images is constructed so that they can be manipulated in a more realistic manner. SUMMARY [0008] The invention relates generally to a collaborative teleconferencing system and method of using the same for generating telestrations and annotations on streaming medical imagery for tele-consultation, tele-collaboration, tele-monitoring, tele-proctoring, and tele-mentoring with others users. [0009] The apparatus includes an image acquisition system adapted for receiving and transmitting medical images, constructed from a computer having communications capability adapted for acquisition and transmission of video signals. [0010] A computer can be defined as typically made of several components such as a main circuit board assembly having a central processing unit, memory storage to store programs and files, other storage devices such as hard drives, and portable memory storage, a power supply, a sound and video circuit board assembly, a display, and an input device such as a keyboard, mouse, stylus pen and the like allowing control of the computer graphics user interface display, where any two or more of such components may be physically integrated or may be separate. Any user on the network can store files on the server and a network server is a computer that manages network traffic. [0011] The present invention improves on existing telestration techniques via the addition of virtual telestration tools that can physically manipulate the video images in a natural way based on a physics model of the object(s) being displayed. Telestration techniques described in prior art rely on freehand drawing of lines or shapes which are then displayed as overlays onto the video images. In the current embodiment, the user controls virtual tools which are able to cut, push, pull, twist, and suture the video images as if they were actually manipulating human tissue. [0012] While the current embodiment is a natural fit for telestrating/telementoring over real-time or stored medical images, such as with surgical telemedicine, the method can be applicable to any telestration requiring one user to demonstrate the use of a tool to an operator who is actually using the tool at that time. Although this technique is naturally suited to such remote student-mentor scenarios, it can also be applied to single-user interfaces. Most notably, with the application of the computational physics model included in the current invention, the user can practice a technique in a virtualized manner on live video images prior to actually performing the maneuver. [0013] This flexibility makes the technique adaptable for the use in remote fieldwork. For example, a telecommunications technician working in a remote location can receive realtime guidance from an expert located elsewhere. Through virtual tool telestration, the expert can annotate which segments to push, pull, twist, and cut in a realistic, but still virtualized manner. The local technician can also use the same annotation tools to practice the task under the guidance of the expert before actually performing the task. By adjusting parameters of the virtual video mesh and computational physics model described below, these annotation techniques can be applied to approximate any objects displayed within the video. [0014] The present invention is accomplished using a combination of both hardware and software. The software used for the present invention is stored on one or more processor readable storage media including hard disk drives, RAM, ROM, optical drives, and other suitable storage devices. In alternative embodiments, some or all of the software may be replaced with dedicated hardware, including custom integrated circuits and electronic processors. [0015] The advantages and novelty of the present invention will appear more clearly from the following description and figures in which the preferred embodiment of the invention is described in detail. BRIEF DESCRIPTION OF THE DRAWINGS Description List [0016] Within the figures, the following reference characters are used to refer to the following elements of the exemplary system illustrated in the drawings. [0017] 10 is an exemplary video stream. [0018] 12 is a 3D mesh object virtual tool exemplification. [0019] 14 is a tele-video mesh overlay. [0020] 16 is an exemplary mesh deformation. [0021] 18 is an exemplary mesh tear. Figures [0022] FIG. 1 is a detailed view of the virtual mesh telestration. In this example, a rectangular 12 -column grid ( 14 ) of equilateral triangles (aka virtual mesh) is constructed via computer graphics. Each vertex (black circle) is connected to another via a computational physics model (spring) which calculates the vertex's three-dimensional position using pre-programmed parameters, including a spring constant, gravitational acceleration, and a damping factor. The border vertices (black squares) remain in fixed positions. The video image of an outstretched left arm ( 10 ) is superimposed onto the virtual mesh. A virtual scalpel ( 12 ) is superimposed over both 10 and 14 . [0023] FIG. 2 is a detailed view based on FIG. 1 after the virtual scalpel has been moved to the left which simulates a cut to the virtual mesh ( 12 ′→ 12 ). The vertices of the virtual mesh ( 14 ) move according to the computational physics engine and create new sub-triangles within the mesh ( 16 ). This movement creates a void ( 18 ) in the mesh. The superimposed video image of the outstretched left arm ( 10 ) moves according to the displacement of the associated vertices of the virtual mesh and gives the appearance that the virtual scalpel ( 12 ) has in fact “cut” the arm in a realistic manner. Nevertheless, although the original video image is displayed in a distorted manner, the data (and the actual arm) remain unchanged. [0024] FIG. 3 is a detailed view of the virtual mesh telestration using a forceps tool ( 12 ). As with FIG. 1 , the virtual mesh is constructed with a 12-column rectangular arrangement of equilateral triangles ( 14 ) whose vertices move according to a computational physics model (spring). A video image of an outstretched left arm ( 10 ) is superimposed onto the virtual mesh. [0025] FIG. 4 is a detailed view based on FIG. 3 after the virtual forceps have moved a vertex up and to the left ( 12 ′→ 12 ). With this tool movement, no vertices are created nor destroyed, but instead move according to the computational physics model (stretched and squeezed springs). The superimposed video image of the outstretched left arm ( 10 ) moves according to the displacement of the associated vertices of the virtual mesh and gives the appearance that the virtual forceps has pulled a section of the arm up and to the left. Nevertheless, although the original video image is displayed in a distorted manner, the data (and the arm) remain unchanged. [0026] FIG. 5 is a workflow diagram of the application and method. A video source (# 3 ) is captured by a video telestreamer (# 2 ) which digitizes its content and transmits it over telecommunication lines in realtime. A virtual tool telestrator (# 1 ) receives the video telestream and allows the client to annotate the video images using virtual telestration tools. These annotations are streamed back to the telestreamer (# 2 ) which updates the original video source (# 1 ) stream with the annotated version. Note that multiple 3D virtual tool telestrators (# 1 ) may act as clients to the video telestreamer (# 2 ). All clients view the same video images and can annotate them independently. DETAILED DESCRIPTION [0027] In the following description, a preferred embodiment of the invention is described with regard to process and design elements. However, those skilled in the art would recognize, after reading this application, that alternate embodiments of the invention may be implemented with regard to hardware or software without requiring undue invention. [0028] General Features of the Method and System [0029] There are 3 main components to this method: [0030] (1) the virtual mesh [0031] (2) the UV texture map [0032] (3) the virtual tools. [0033] Virtual Mesh [0034] The virtual mesh is a computer graphics representation of a video display where each vertex of the mesh corresponds to a position within the video image. In a static display, the virtual mesh is analogous to a pixel map of the video image. In this invention, however, the vertices of the virtual mesh are not necessarily aligned with the pixels of the video image. More importantly, the locations of the vertices are not fixed in space, but rather can move with respect to one another as if each vertex were a physical object (or a part of a physical object) in the real world. [0035] In the current instantiation, the virtual mesh is constructed using equilateral triangles arranged in a 12-column grid ( FIG. 1 ). Equilateral triangles were chosen because they are computationally easier to sub-divide than other geometric shapes. Nevertheless, any shape (2D or 3D) can be used to create the mesh. In addition, multiple meshes of varying configurations can be produced to represent features and objects within the streamed imaging modality. Further, the overall mesh is rectangular in shape because video images are usually displayed in this manner; but, the shape of the mesh can changed to conform to the needs of the telestration. [0036] Machine vision techniques may be applied to sub-divide the mesh according to objects within the video image. For example, a mesh displaying a video of an automobile could be sub-divided into body, wheels, and background--with each sub-segment of the mesh being programmed to mimic the physical characteristics of the objects they represent. This would compensate for any relative movement among the camera, objects, or field of view. [0037] In the current embodiment, a surgeon could identify regions of interest within the image (e.g. major organs, nerves, or blood vessels) by encircling them with conventional freehand drawing telestration. An optical flow algorithm, such as the Lucas Kinade method, could be used to track each region of interest within the realtime video. The virtual mesh would be continually updated to change the parameters of the sub-meshes based on the regions of interest. This would ensure, for example, that a cut in the mesh which was made to overlay the prostate would keep the same relative position and orientation with respect to the prostate regardless of movement. [0038] The vertices of the virtual mesh are interconnected in movement using a computational physics model of the object being represented. In the current instantiation, the physics model assumes that vertices are connected via springs which obey the physical constraints of Hooke's Law and gravitational acceleration. By changing the parameters, such as spring constant, gravitational acceleration, and damping factor, the behavior of the virtual mesh can be adjusted between various levels of fluidity. For example, the current embodiment can be made to approximate human skin, but different types of human tissue could also be represented in the same telestrated video. [0039] It should be noted that although the computational physics model is currently formulated to simulate movement in typical environments, it could be equally used to simulate movement of objects in exotic environments, such as in space or underwater by computationally changing the nature of the virtual mesh. [0040] UV Mapping [0041] UV mapping is a three-dimensional (3D) modeling process which maps a two-dimensional (2D) image onto the three-dimensional surface. Other patents and techniques sometimes refer to this technique as “texture mapping”. Every 3D object in computer graphics is made up of a series of connected polygons. UV mapping allows these polygons to be painted with a color from a 2D image (or texture). Although in its current instantiation the virtual mesh is a 2D object, it can be texture mapped with a 2D video image in the same manner. Further, using the UV mapping, the same technique can be applied to true 3D virtual meshes of any configuration. [0042] By superimposing the video image onto the virtual mesh using a UV map, the video image will be distorted whenever the virtual mesh is distorted. In effect, the process allows points and segments of the video image to move and react to the telestration. In fact, if polygons within the virtual mesh are deleted (e.g. cutting the mesh as in FIG. 2 ), the projected video image will not display the area which is mapped to those polygons. Similarly, if the polygon changes shape (e.g. pulling the mesh as in FIG. 4 ), the projected video image will display the area mapped to that polygon with precisely the same geometric distortion. [0043] Virtual Tools [0044] Virtual tools are computer-generated objects which are programmed to interact with the virtual mesh according to a computational physics engine. In the current instantiation, the invention uses three virtual tools: a virtual scalpel, a virtual forceps, and a virtual suture. All three tools are programmed to push, pull, and twist the virtual mesh according to the physics engine using standard ray-casting techniques and colliders. [0045] The virtual scalpel separates the connections between the triangles that are in contact with the scalpel tip. This results in a void between those triangles and makes the video image appear to have been cut in the mapped area. Further, if an entire section of the virtual mesh is “cut” from the existing mesh, the UV mapped area of the video image will appear to be physically removed from the remainder of the video image. The edge of the cut mesh then acts as an edge of tissue; so the edge of the cut surface will deform when manipulated, independent of the other side of the cut mesh. [0046] The virtual forceps attaches to the triangle closest to the forceps tip when activated. It creates an external force on the attached triangles within the computation physics model of the virtual mesh. The forceps can be used to drag the attached triangles ( FIG. 4 ) and gives the illusion that the video image is being grabbed by the forceps in a realistic manner. After the forceps is deactivated, the external force is removed from the computational physics model. The affected triangles will continue to react to internal (reaction) forces until they eventually return to a steady-state position. [0047] The virtual suture allows the telestrator to add connections between triangles. The suture is modeled by a spring. When activated, the suture tool adds a spring to the computational physics engine between any two points specified. This tool can be used to join previously cut sections of the virtual mesh. [0048] Although in its current instantiation the virtual tools are limited to these three, the flexibility of the computational physics engine allows the technique to be readily expanded to include the use of any tool or object which can be modeled, including drills, retractors, stents, and suction devices. [0049] Application [0050] In order to illustrate the method proposed in this invention, consider the field of surgery. Adequate surgical collaboration requires one practitioner demonstrating a technique to another practitioner. Current telestration techniques are unable to demonstrate surgical techniques, such as dissection, clamping, and suturing. It is not sufficient to know simply where or when to cut; the surgeon must be able to also demonstrate how to cut--how to hold the instrument, how hard to push, and how quickly to move. These limitations of conventional telestration as described in prior art are exacerbated in situations where the practitioners may be in different locations. These telestration techniques are insufficient for true surgical telementoring or any video annotation requiring a procedure to be demonstrated especially when complex techniques are being demonstrated to new students. [0051] Virtual tool telestration, as described herein and which makes up at least a part of the present disclosure, may allow the mentoring surgeon to interact with a virtual video-overlay mesh of the operative field and mimic the technique needed to perform the operation. The surgeon mentor can demonstrate suturing and dissecting techniques while they are virtually overlaid on a video of the actual operative field. Notably, the mentoring surgeon can demonstrate the surgical technique effectively without actually changing the operative field. [0052] Current telestration methods have limited conventional telemedicine to non-surgical fields of medicine. However, with the system and method of the present disclosure, it may be possible that telemedicine/telementoring will become crucial to surgical practice and, indeed, any field where collaboration requires demonstrating rather than merely describing an idea. [0053] In fact, there is growing concern that the advance of minimally invasive surgery (MIS) is grossly outpacing the evolution of surgical training. This application will assist in bridging the learning curves for surgeons performing the MIS procedures. In addition, as live video and other imaging modalities become more prevalent in clinical practice, the telestration described herein will become inherent to all forms of medicine. A virtual tool telestrator is the critical element to enable adequate surgical telestration. [0054] Additionally, telestration is currently used in a number of non-medicine fields. The most common application is with professional sports broadcasting whereby sports commentators can “draw” on the televideo and emphasize certain elements of the video, such as the movement of the players. Adding 3D virtual telestration tools, as described herein, to these existing telestration devices and tools could be invaluable to such modalities. For example, bomb disposal experts could use virtual tools to interact with the remote video signal transmitted by ordinance disposal robots to signal the robot to push or pull certain areas of the field of view. Sculptors could use virtual hands to indicate to their student the proper finger position on a piece of unformed clay—and demonstrate how the clay should move without actually affecting the real world object. Any real world object that can be imaged can be transmitted and manipulated in a collaborative, yet virtualized manner. [0055] Virtual tool telestration may be equally effective in a 2-D or a 3-D environment or representation and differs from what currently exists in the field of telestration. It is typically constructed from two components ( FIG. 5 ): [0056] 1. a 3D virtual tool telestrator [0057] 2. a live video telestreamer [0058] These elements may be related to each other in the following exemplary and non-limiting fashion. [0059] The live video telestreamer (# 2 ) may be a computer networking device which allows for audio and video signals to be sent in realtime to remote clients. In one embodiment, the live video telestreamer captures streaming imagery and transmits it over the internet using a real-time streaming protocol (RTSP) in a H.264 video compression/decompression (codec) format. [0060] The virtual tool telestrator (# 1 ) may be a computer program which displays the telestream (# 2 ) as a 3D mesh object on a video monitor, allows for remote users to overlay virtual 3D tools (e.g. forceps, scalpels) which can be moved by the remote user and which can interact with the video mesh. For example, the remote user may virtually grab a section of the video mesh with the forceps and that part of the mesh will move in a manner similar to that of the actual object being displayed in the video (e.g. a section of the bladder neck during prostate removal). [0061] The virtual tool telestrator (# 1 ) will transmit the virtualized surgical telestration of the remote user back to the source live video telestreamer (# 2 ) for display. To conserve transmission bandwidth, the virtual tool telestrator (# 1 ) only sends the position and orientation of the virtual tools and the virtual mesh to the live video telestreamer (# 2 ) along with the timestamp of the current video frame. In this manner, bandwidth requirements and latency are minimized. [0062] The virtual tool telestrator (# 1 ) may be comprised of computer software written, by way of an exemplary and non-limiting example, with mostly open-sourced software development packages, such as by using a programming environment like but not limited to C++, C#, Mono, Silverlight, and Unity3D. The telestrator may include 3D graphics rendering engine, such as but not limited to Unity3D, which may be used to display the 3D virtual tools and a virtual mesh with triangular vertices. The telestrator may also include a physics simulator, such as but not limited to PhysX, to handle the virtual simulation and interaction between the virtualized tools and the video mesh. The telestrator may also include a multimedia player, such as but not limited to AVPro LiveCapture, which may be used to overlay a video input stream onto the virtual mesh to create a virtual operative field. The telestrator will use human input devices, such as the Razer Hydra joystick or the Geomagic Touch to control movement of the virtual tools in a natural way. [0063] A similar computer program exists on the live video telestreamer (# 2 ). However, unlike the virtual tool telestrator (# 1 ), this program renders the graphics without the computational physics engine. Instead, the position and orientation of the virtual tools and virtual mesh that were passed back from the virtual tool telestrator (# 1 ) are used to create an exact rendering of the virtual tool telestration at that timestamp. In this way, the live video telestreamer (# 2 ) can display an exact rendering of the virtual tool telestration to all clients simultaneously. [0064] While the invention has been described with reference to preferred embodiments, it is to be understood that the invention is not intended to be limited to the specific embodiments set forth above. Thus, it is recognized that those skilled in the art will appreciate that certain substitutions, alterations, modifications, and omissions may be made without departing from the spirit or intent of the invention. Accordingly, the foregoing description is meant to be exemplary only, the invention is to be taken as including all reasonable equivalents to the subject matter of the invention, and should not limit the scope of the invention set forth in the following claims.

Apparatus and method for receiving and transmitting streaming live imagery data and audio signals in real time is provided. Imagery data and audio signals are acquired through a telestreamer input device and streamed to one or more remote recipients, allowing remote operators to electronically collaborate by telestrating, annotating, and sketching image overlays. Streaming video images displayed on a monitor are superimposed onto a virtual mesh projected via computer graphics. Vertices of the virtual mesh move according to a computational physics engine. Virtual tools are also superimposed onto a virtual mesh projected via computer graphics. The virtual tools interact with the virtual mesh to deliver real time, realistic modifications of the streaming image data. Recursive positioning of mesh layers and creation of a multi-layered virtual mesh enhance the realistic nature of the modified streaming image data.

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of co-pending U.S. patent application Ser. No. 10/989,008, filed on Nov. 15, 2004, entitled PORTABLE BASKETBALL SYSTEM; which is a continuation of U.S. patent application Ser. No. 10/212,443, filed on Aug. 5, 2002, entitled PORTABLE BASEKTBALL GOAL SYSTEM, now U.S. Pat. No. 6,916,257; which is a continuation of U.S. application Ser. No. 09/638,529, filed on Aug. 14, 2000, entitled ADJUSTABLE WHEEL ENGAGEMENT ASSEMBLY FOR BASKETBALL GOAL SYSTEMS, now U.S. Pat. No. 6,432,003; which is a continuation-in-part of patent application Ser. No. 09/249,275, filed on Feb. 11, 1999, entitled PORTABLE BASKETBALL GOAL SYSTEM HAVING TWO-PART BASE SUPPORT ASSEMBLY, now abandoned, each of which are hereby incorporated by reference in their entireties. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to basketball goal assemblies and, more particularly, to novel adjustable wheel engagement assemblies for basketball goal systems employing a unique structural design that facilitates selective movement of the basketball goal system in relation to a playing surface. [0004] 2. The Relevant Technology [0005] As the game of basketball has increased in popularity a greater number of people have purchased basketball goals for use at their homes. Typically, home basketball goals are permanently mounted in a manner such that the driveway of the home serves as a playable basketball court, as few homes have sufficient land surrounding the home to dedicate space for exclusive use as a basketball court. In some instances, deciding where to position or mount a basketball goal can pose some playing difficulties. For example, mounting a basketball goal adjacent to the driveway of a home may precipitate a risk to any traffic in the driveway, resulting in potential injury to the players or damage to parked or moving automobiles. [0006] In some cases, the perfect location for mounting a basketball goal is the place where permanently mounting the basketball goal cannot be easily accomplished. Such a location may be where there is concrete or asphalt on the ground. To permanently mount the basketball goal assembly would therefore require breaking up the concrete or asphalt and then repairing the receiving hole after inserting an end of a support pole into the ground. Such a procedure could be relatively expensive and would most likely leave the driveway appearing unsightly at least during the period of construction and repair. [0007] Other disadvantages are also associated with permanently installed basketball goal assemblies. Since basketball goal assemblies are generally mounted to a surface outdoors, they are generally exposed to the harsh elements of the weather throughout the entire year. As appreciated, constant exposure to the elements of the weather (e.g., rain, snow, sleet, high temperatures) will typically cause the component parts of the basketball goal assembly to prematurely wear by promoting oxidation. Premature oxidation can be particularly troublesome in basketball goal assemblies having any moving parts, such as height adjustment mechanisms or breakaway rim assemblies. Moreover, consistent exposure to the elements of the weather may cause premature failure of such mechanisms. [0008] Mounted basketball goal assemblies that are utilized in an indoor environment may suffer from similar disadvantages associated with permanent placement. For example, schools typically have a gymnasium which generally serves many functional purposes. Having several basketball goals permanently mounted for use in the gymnasium may preclude, or at least interfere, with certain other activities. On formal occasions, objection may be made to the appearance of one or more permanently mounted basketball goals. [0009] In response to these and other disadvantages inherent in basketball goal assemblies that are permanently mounted to a surface, those skilled in the art began developing portable basketball assemblies. In order for a portable basketball goal assembly to be effective, sufficient weight must be employed to maintain the basketball goal in a generally rigid, upright position for use when playing the game of basketball or shooting baskets. Hence, portable basketball goal assemblies were developed utilizing a great deal of weight at the base, thereby making the goal assembly particularly difficult to move and typically requiring the assistance of several people to set up or relocate the basketball goal. Additionally, such designs can be prohibitively expensive for people desiring to purchase one for home use. [0010] Other prior art portable basketball goal assemblies were developed which incorporate removable weights such as, for example, sand bags or metal weights, that are generally disposed in relation to the support structure. A principal disadvantage in using these types of removable weights is that they can be extremely heavy, difficult to lift and arrange. Accordingly, although the basketball goal assemblies employing such designs may be easier to move in relation to permanently mounted goal assemblies, the weights or weighted members are not. [0011] In an attempt to make portable basketball goal assemblies that are better suited for home use, support bases were developed having a hollow cavity sufficient for receiving a ballast material. The ballast material introduced into the cavity of the support base may include water, sand or other suitable material. Such portable basketball goal assemblies can be more easily moved to a desired location where the support base is then filled with the ballast material, thereby providing sufficient weight to maintain the goal in a generally rigid, upright position for game play. A principal advantage of using a support base fillable with a ballast material is that water, sand or other fillable materials are usually inexpensive and convenient to use. When it is desired to move these prior art portable basketball goal assemblies, the ballast material is generally emptied out of the internal cavity in the support base and then the basketball goal assembly is moved. However, having to fill and empty the goal each time the goal is to be set up or moved requires time and is inherently inconvenient. [0012] To assist in moving prior art basketball goal assemblies, one or more wheels were incorporated into support bases to facilitate movement of the basketball goal assembly. For example, one such wheeled support base design is disclosed wherein the support base generally engages the ground and rests on one or more base wheels. Movement is achieved by lifting and tilting the support base generally on an end until substantially the weight of the base rests on the wheels. Thus, the base wheels serve as a rotating fulcrum upon which the effective weight of the basketball goal assembly may be supported such that the basketball goal assembly then is maneuverable in this position from place to place. [0013] A disadvantage to prior art base support wheel assemblies is that pivoting a heavy base to facilitate its relocation can be difficult for some people and especially for children to move. Specifically, attempting to pivot a heavy support base may present dangers associated with having the entire basketball goal assembly dropped on one or more persons or children. This is especially true when someone without sufficient physical strength attempts to pivot or move a heavy support base. Whereas, a sudden release of the heavy base can cause bodily injury or damage to the base or those in its vicinity. [0014] In addition, many portable basketball goal assemblies do not fully engage the playing surface when positioned for game play. This is particularly problematic for basketball goal assemblies that incorporate wheels in the support base. For example, a portion of the base must be lifted off the playing surface to keep the basketball goal assembly from resting on the wheels and being somewhat moveable under little force. As a result, there is less friction between the support base and the playing surface, therefore the support base is liable to move during play, especially during slam dunks and other maneuvers that place a substantial lateral force on the basketball goal assembly. [0015] Another disadvantage with prior art portable basketball goal assemblies is that many are formed having the support pole positioned only a few inches from the inner edge of the base. As a result, the moveable support base extends outwardly and underneath the basketball net. This makes it difficult to execute game play strategies in which a player is positioned behind or beneath the basketball net because the support base extends into this area of game play, and may even cause a player to stumble. [0016] Moreover, many prior art portable basketball goal assemblies do not permit lateral (sideways) motion of the front portion of the support base. Thus, anyone attempting to move the heavy support base and attached pole and basketball goal support must intuitively push the assembly backward to move it or, alternatively, swing the rear portion of the support base around in an effort to orient the base before attempting to move the basketball goal assembly. This can be particularly troublesome when the basketball goal assembly is to be stored in a narrow enclosure; there may not be sufficient room to pivot the support base in order to remove the basketball goal assembly from the enclosure. As appreciated, small adjustments in the positioning of these type of prior art basketball goal assemblies for game play are generally more difficult if the front portion of the assembly, which supports the basketball goal, does not the capacity to be moved laterally. [0017] Furthermore, many prior art portable basketball goal assemblies cannot be manipulated from a stationary configuration to a mobile configuration without changing the position of the device (i.e., forceably tilting the support base). This makes minor repositioning even more difficult, as a user must attempt to move the support base and then try to guess where the base will end up after the basketball goal assembly is returned to a stationary configuration. A user may thus find it exceptionally difficult to move these prior art basketball goal assemblies only an inch or two. [0018] As noted above, some of the prior art designs of portable basketball goal assemblies also have a number of other problems. For example, some have portions that protrude from the support base and thereby create a playing hazard. Others have moving parts that may pinch body parts as they fold or collapse together. Many prior art designs of portable basketball goal assemblies are also overly expensive and difficult to assemble because they require the use of special fixtures such as bearings, collars, and the like to retain metal parts such as wheels, posts, and sliding members in engagement with the support base. [0019] Consistent with the foregoing, it would be an advancement in the art to provide an improved support base for portable basketball goal assemblies that can be easily moved by one person without having to pivot a significant portion of the weight of the support base in order to facilitate movement. It would be a further advancement in the art to provide a novel support base and wheel system for basketball goal assemblies that can be readily adapted into a playing position, thereby being resistant to movement during game play. [0020] Yet further, it would be an advancement in the art to provide a portable basketball goal system that is readily movable, as described above, in which substantially the entire underside of the base rests upon the playing surface during game play, so as to impart additional stability and resistance to forces acting on the basketball goal assembly which may tend to move the assembly when configured in the playing position. A still further advancement over the prior art devices would provided by such a basketball goal system wherein the support base does not extend underneath the basketball net, thus impeding net play or causing potential injury to one or more players. [0021] It would be a further advancement in the art to provide a portable basketball goal assembly having a front portion that could be easily moved in a lateral direction. Furthermore, an advancement would be provided by a portable basketball goal assembly that could be made mobile without having to significantly shift the weight of the assembly for movement, so that minor positioning adjustments may easily be made. Further advancements in the art may stem from providing a support base that is substantially free from protruding objects or members that may impede normal use or game play, and substantially free from folding or compressing areas accessible to a user. Still further advancements in the art would be to provide a basketball goal assembly in which comparatively few fixtures are required to retain moving or assembled parts within the support base. [0022] Such a device is disclosed and claimed herein. BRIEF SUMMARY OF THE INVENTION [0023] The present invention is directed to a basketball goal system employing a novel adjustable wheel engagement assembly that facilitates movement of the basketball goal system relative to a playing surface. One presently preferred embodiment of the novel basketball goal system of the present invention comprises a rigid support pole having a first end configured to supportably engage a basketball goal above a playing surface and a second opposing end adapted to engage a movable support base. The support base may include a receiving aperture formed in a first portion of the support base, wherein the receiving aperture is adapted to receive and maintain the second end of the support pole in either a fixed or pivotal relationship thereto. The support base further includes sufficient weight appropriately disposed along its dimensional length and width so as to support the rigid support pole and the basketball goal in a general upright position over a playing surface for game play. [0024] In one presently preferred embodiment, an adjustable wheel assembly is operably disposed proximate the front portion of the support base having the receiving aperture for receiving the support pole. Preferably, the adjustable wheel assembly comprises a caster rotatably disposed in relation to a support assembly. As will be appreciated, one or more rollers may be supportably disposed in relation to the support base between the front portion and the back portion of the base, if desired. In one presently preferred embodiment of the present invention, the adjustable wheel assembly and one or more rollers, in combination, may provide sufficient support to the base to allow for selective maneuvering of the basketball goal system to various locations for either game play or storage. [0025] An engaging member, moveable between an extended position and a retracted position, is disposed in operable engagement to the support pole. In one presently preferred embodiment, the engaging member comprises a proximal end pivotally connected to the second end of the support pole contiguous the front portion of the base and proximate the receiving aperture that receives the support pole. The engaging member further comprising a distal end configured to engageably receive a hand of a user (e.g., forming a handle). Preferably, the engaging member is pivotally engages the support pole such that the engaging member may be selectively pivoted between an extended position wherein the distal end of the engaging member extends substantially outward and at an angle relative to the generally upright disposition of the support pole and a retracted position wherein the distal end of the engaging member extends substantially parallel to the disposition of the support pole positioned for game play. [0026] In one presently preferred embodiment, the adjustable wheel assembly may comprise a caster mounted on a slider that selectively extends outward from a hollow channel formed at the second end of the support pole. The distal end of the engaging member may include a cam adjustment surface designed to rest upon a follower that is attached to the slider. In operation, the rotational positioning of the cam adjustment surface, when selectively pivoting the engaging member between the retracted position and the extended position, subsequently controls the vertical position of the follower, and therefore that of the slider. [0027] As noted above, in the retracted position, the engaging member is generally disposed substantially upward and parallel to the disposition of the support pole. In operation, the cam adjustment surface of the engaging member may be pivoted in such a way that the follower remains in an upward position. Consequently, the slider of the adjustable wheel assembly may be retained within the internal periphery of the hollow chamber of the support pole, and the caster may therefore be retracted such that the weight of the basketball goal system does not rest upon the adjustable wheel assembly, but rather on the contacting surface of the base support to prevent movement of the basketball goal system. Although one or more rollers may remain in constant contact with the playing surface, the rollers alone are ineffective to allow movement of the support base from one location to another when the engaging member is selectively positioned in the retracted position. Significant movement of the basketball goal system is thus prevented during game play when the engaging member is disposed in the retracted position and the caster is selectively retracted from supporting engagement with the playing surface. [0028] In the extended position, the engaging member extends substantially outward and at an angle relative to the generally upright disposition of the support pole for game play. In operation, the cam adjustment surface of the engaging member may be rotated to a position in which the follower is forced generally downward in relation to the support base. Consequently, the slider generally slides outward from within the hollow channel at the second end of the support pole and, as the caster supportably engages the playing surface, the front portion of the support base is subsequently lifted off the playing surface so that the weight of the front portion of the support base supportably rests upon the caster of the adjustable wheel assembly. As noted above, the distal end of the engaging member may then used as a handle or lever for gripping in order to facilitate maneuvering of the support base and, accordingly, the basketball goal system from one location to another for game play or storage. [0029] Thus, it is an object of the present invention to provide a novel adjustable wheel assembly for a basketball goal system having an engaging member adapted to be selectively positionable between a retracted position such that the support base is restricted from significant movement in relation to the playing surface and an extended position which facilitates controlled movement of the support base and, correspondingly, the basketball goal system from one location to another. [0030] It is an additional object of the present invention to provide a support base for a basketball goal assembly that may be moved from one location to another without having to physically lift or tilt the support base from its substantially horizontal position relative to the playing surface. [0031] It is a further object of the present invention to provide a basketball goal system having an engaging member comprising a distal end that serves as a handle or lever for gripping by a user when attempting to manually maneuver the basketball goal system from one position to another. [0032] It is a still further object of the present invention to provide a novel adjustable wheel assembly for basketball goal systems that maintains a substantial frictional area between the support base and the playing surface for stable game play when the engaging member is disposed in a retracted position and, correspondingly, a significant portion of the length of the slider is selectively disposed in the hollow channel formed in the second end of the support pole. [0033] Additionally, it is an object of the present invention to provide a support base for a basketball goal system that remains substantially displaced from beneath a basketball net to make net play safer and easier. [0034] It is also an object of the present invention to provide a support base for a basketball goal system, wherein a front portion of the support base can be moved in a lateral direction by means of displacing the engaging member in an extended position, thus disposing the caster of the adjustable wheel assembly in supportable relation to the playing surface so as to facilitate easy maneuvering of the basketball goal assembly from one location to another. [0035] These and other objects and features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS [0036] To further clarify the above and other advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: [0037] FIG. 1 is a perspective view of one presently preferred embodiment of a basketball goal system in accordance with the present invention; [0038] FIG. 2 is a side view of the embodiment of the basketball goal system of FIG. 1 illustrating a support pole, a support base, and an extending member, wherein the basketball goal system is disposed in a stationary configuration for game play; [0039] FIG. 3 is a side view of the embodiment of the basketball goal system of FIG. 1 illustrating an engaging member disposed in an extended position and an adjustable wheel assembly supportably engaging the playing surface, wherein facilitating selective movement of the basketball goal system from one location to another; [0040] FIG. 4 is an exploded, cross-sectional, side view of a front portion of the support base illustrating the pivotal relationship of the extending member and the adjustable wheel assembly of the embodiment of the basketball goal system of FIG. 1 , wherein a contacting surface of the support base remains in frictional contact with the playing surface to prevent movement of the basketball goal system; [0041] FIG. 5 is an exploded, cross-sectional, side view of the front portion of the support base illustrating the structural relationship between the cam surface of the engaging member and the follower attached to the slider of the adjustable wheel assembly of the embodiment of the basketball goal system of FIG. 1 , wherein the slider slidably extends outwardly from its telescopic engagement with the second end of the support pole and thereby positions the caster in supportable relation to the playing surface so as to lift a portion of the contacting surface of the support base from its frictional engagement with the playing surface so as to allow for easy transportation of the basketball goal system from one location to another; [0042] FIG. 6 is a perspective view of another embodiment of the basketball goal system, illustrating the engaging member disposed in a playing position; [0043] FIG. 7 is a perspective view of the embodiment of FIG. 6 with the engaging member disposed in an extended position; [0044] FIG. 8 is a rear perspective view of the embodiment of FIG. 6 showing the engaging member secured in the playing position; [0045] FIG. 9 , is a perspective view of another embodiment of the support base of the basketball goal system; [0046] FIG. 10 is a bottom plan view of the support base of the basketball goal system; [0047] FIG. 11A is a side view of another embodiment of the basketball goal system with the engaging member disposed in the playing position; [0048] FIG. 11B is a side view of the embodiment shown in FIG. 11A with the engaging member disposed in the extended position; and FIG. 12 is a perspective view of another embodiment of the basketball goal assembly illustrating the engaging member in the extended position for storage. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0049] It will be readily understood that the components of the present invention, as generally described and illustrated in the Figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the system and method of the present invention, as represented in FIGS. 1 through 5 , is not intended to limit the scope of the invention, as claimed, but it is merely representative of the presently preferred embodiments of the invention. [0050] The presently preferred embodiments of the invention will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. [0051] One presently preferred embodiment of the present invention, designated generally at 10 , is best illustrated in FIGS. 1 and 2 . As shown, the basketball goal system 10 comprises a rigid support pole 14 having a first end 13 configured to supportably engage a basketball goal assembly 30 above a playing surface 26 and a second opposing end 13 adapted to mountably engage a support base 12 . Structurally, the support base 12 includes a receiving aperture 28 formed in a front portion 36 of the support base 12 , wherein the receiving aperture 28 is adapted to receive and maintain the opposing second end 13 of the support pole 14 in either a fixed or pivotal relationship to the base 12 . The support base 12 preferably comprises sufficient weight so as to support the pole 14 and the basketball goal assembly 30 in a general upright position over a playing surface 26 . In addition, one or more brace supports 15 may have opposing ends adapted to provide a structural connection between the support base 12 and the pole 14 so as to assist in providing structural support to retain the support pole 14 and the attached basketball goal assembly 30 in a generally upright configuration for game play. [0052] In one presently preferred embodiment, the basketball goal assembly 30 may include a backboard 16 , a rim 18 , a net 20 , and upper and/or lower engagement arms 19 a , 19 b pivotally connected between the basketball backboard 16 and the first end 11 of the support pole 14 . As contemplated herein, an adjustment assembly (not shown) may be operably disposed in relation to the upper and/or lower engagement arms 19 a , 19 b of the basketball goal assembly 30 such that selective manipulation of the adjustment assembly results in a corresponding adjustment in the height of the basketball goal assembly 30 above the playing surface 26 . [0053] The support base 12 of the present invention is preferably formed of a substantially sturdy, rigid material. For example, the support base 12 may be formed of a polymeric material such as, for example, a low-density linear polyethylene. It will be readily appreciated by those skilled in the art, however, that a wide variety of other suitable materials such as wood, fiberglass, ceramic, any of numerous organic, synthetic or processed materials which are mostly thermoplastic or thermosetting polymers of high molecular weight, and/or other composite or polymeric materials are possible which are consistent with the spirit and scope of the present invention. [0054] The support pole 14 is preferably constructed of a rigid material having comparatively high resistance to impact and yielding. Although certain plastics and polymers may be used, the support pole 14 of one presently preferred embodiment of the present invention is formed of metal, such as steel or aluminum, or of a sufficiently sturdy composite material. It will be readily appreciated by those skilled in the art that the support pole 14 of the present invention may comprise two or more sectional members that can be assembled together to form a single support pole having sufficient structural integrity so as to support a goal support assembly 30 above a playing surface 26 . For example, the support pole 14 may include two or more sectional members that telescopically engage each other to provide a single support pole 14 . [0055] Referring now to FIGS. 4 and 5 , in one presently preferred embodiment of the present invention, the support base 12 is formed having a cavity 60 having an internal periphery sufficient for receiving a ballast material such as, for example, water, sand, or the like. In operation, the ballast material provides sufficient weight and adequate support to retain the support pole 14 and the basketball goal assembly 30 in a general upright position during rigorous game play. In such an embodiment, the support base 12 may be configured with an opening (not shown) formed in the upper surface 40 of the support base 12 such that when the base 12 is filled, for example, with water to the point that the water level in the support base 12 reaches the opening, a void remains within the upper portion of the cavity 60 which does not fill with water. This is to allow for expansion of the water in the case of freezing temperatures. [0056] In operation, after introducing the ballast material into the internal periphery of the cavity 60 of the support base 12 , a closure or cap (not shown) may be secured in the face of the opening to prevent the displacement of the ballast material from the cavity 60 of the support base 12 . As will be appreciated, the support base 12 may not include a cavity 60 for introducing a ballast material, but rather comprise sufficient weight, in and of itself, to ensure the stability of the basketball goal system 10 when the support pole 14 and the attached basketball goal assembly 30 are disposed generally upward from the playing surface 26 for game play. [0057] Referring back to FIGS. 1 and 2 , in one presently preferred embodiment, the support base 12 comprises a front portion 36 , a rear portion 38 , an upper surface 40 , and a contacting surface 42 . The receiving aperture 28 of the support base 12 , which receives and maintains the second end 13 of the support pole 14 in fixed or pivotal relation thereto, is preferably formed within the front portion 36 of the support base 12 . The engagement between the support pole 14 and the receiving aperture 28 of the support base 12 may include a cross-brace member 66 (e.g., a linear shaft or axle) having a proximate end, a distal end, and an intermediate body portion formed between the proximate and distal ends thereof. In this regard, the proximate end of the cross-brace member 66 may be engageably disposed in relation to the support base 12 and the distal end of the cross-brace member 66 engageably disposed in relation to the support pole 14 . [0058] In one presently preferred embodiment of the present invention, a first and second cross-brace member 66 are formed on opposite sides of the support pole 14 , thus engaging opposite sides of the receiving aperture 28 of the support base 12 , as best shown in FIGS. 4 and 5 . It will be readily apparent to those skilled in the art that other mechanisms may be constructed in accordance with the inventive principles set forth herein so as to facilitate a fixed or pivotal connection between the support pole 14 and the support base 12 . It is intended, therefore, that the example provided herein be viewed as exemplary of the principles of the present invention, and not as restrictive to a particular structure for implementing those principles. [0059] Also disposed in relation to the cross-brace member 66 is an engaging member 22 . As best illustrated in FIGS. 1-3 , the engaging member 22 , being selectively moveable between an extended position and a retracted position so as to define an adjustable distance 24 therebetween, is disposed in pivotal engagement to the support pole 14 by means of one or more cross-brace members 66 . In one presently preferred embodiment, the engaging member 22 comprises a proximate end 21 pivotally connected to the second end 13 of the support pole 14 contiguous the front portion 36 of the support base 12 and proximate the receiving aperture 28 which structurally receives the support pole 14 in relation to the base 12 . The engaging member 22 also includes a distal end 23 and an elongate intermediate body portion 25 formed between the proximal and distal ends 21 , 23 thereof. The distal 23 of the engaging member 22 is preferably configured to receive a hand of a user (e.g., forming a handle) to assist in maneuvering the basketball goal system 10 from one position to another when the engaging member 22 is positioned in the extended position. [0060] As noted above, the engaging member 22 is structurally disposed relative to the rigid support pole 14 and the base 12 in such a manner that the engaging member 22 may be selectively pivoted between an extended position wherein the distal end 23 of the engaging member 22 may extend substantially outward and at an angle relative to the support pole 14 (as shown in FIGS. 3 and 5 ) and a retracted position such that the distal end 23 of the engaging member 22 may be positioned substantially parallel to the generally upright disposition of the support pole 14 (as shown in FIGS. 1, 2 , and 4 ). When the engaging member 22 is positioned in the extended position, an adjustable wheel assembly 50 is operably disposed into supportable engagement with the playing surface 26 such that the front portion 36 and at least a portion of the contacting surface 42 of the support base 12 is lifted from its frictional engagement with the playing surface, thereby allowing the basketball goal system 10 to be moved from one location to another. In contrast, when the engaging member 22 is positioned in the retracted position, the adjustable wheel assembly 50 is retracted from supportable engagement with the playing surface 26 such that the contacting surface 42 of the support base 12 remains in frictional engagement with the playing surface, thus restricting movement of the support base 12 and, correspondingly, the basketball goal system 10 . [0061] Referring now to FIG. 2 , one presently preferred embodiment of the support base 12 includes a contacting surface 42 that may be formed having a slight slope upward gently toward the back portion 38 of the support base 12 to expose a roller 44 supportably engaging a portion of the contacting surface 42 . Preferably, a portion of the roller 44 remains in substantial communication with the playing surface 26 when the support base 12 is in the playing position. As will be appreciated, one or more rollers 44 may be supportably disposed in relation to the support base 12 at various positions between the front portion 36 and the back portion 38 of the support base, if desired, to assist in maneuvering the basketball goal system 10 when the engaging member 22 is selectively positioned in the extended position as shown in FIG. 3 . [0062] In one presently preferred embodiment, the roller 44 may comprise a caster or a single cylindrical wheel extending a sufficient length across the width of the support base 12 to assist with maneuvering of the support base 12 when the adjustable wheel assembly 50 is disposed in supportable relation to the playing surface 26 . It is anticipated, therefore, that any arrangement of rollers is herein contemplated to be within the scope of the present invention, so long as the rollers, independent of the adjustable wheel assembly 50 , cannot facilitate significant movement of the support base 12 without selectively disposing the engaging member 22 in the extended position, thus activating the supportable engagement of the adjustable wheel assembly 50 with the playing surface 26 . Preferably, two or more cylindrical wheels 44 are rotatably disposed in relation to the contacting surface 42 of the support base 12 proximate the back portion 38 to provide additional maneuvering support to the support base 12 when engaging the adjustable wheel assembly 50 and thus moving the basketball goal system 10 from one location to another. [0063] The rollers 44 preferably turn about axles that are mounted in at least a portion of the contacting surface 42 of the support base 12 and are thus configured to support translation of the support base 12 along an axis extending between the front and back portions 36 , 38 . The contacting surface 42 , however, fictionally engages the playing surface 26 at the front portion 36 of the support base 12 , so that the support base 12 remains substantially immobile until the adjustable wheel assembly 50 is selectively positioned to supportably engage the playing surface 26 . A substantial portion of the contacting surface 42 of the support base 12 therefore remains in frictional contact with the playing surface 26 to ensure that the basketball goal system 10 remains sufficiently stable even during rough game play. As best illustrated in FIGS. 1 and 2 , the engaging member 22 , when positioned in the retracted position, may be generally oriented substantially vertical in relation to the support base 12 , and may further act as a rebound surface for a basketball during game play. In this regard, it will be appreciated by those skilled in the art that the intermediate body portion 25 of the engaging member 22 may be formed in geometrical configuration or shape sufficient to provide a rebound surface for a basketball. [0064] Referring now to FIGS. 3 and 5 , when the extending member 22 in positioned in the extended position, the distal end 23 of the extending member 22 is disposed outwardly away from the generally upward direction of the support pole 14 . Correspondingly, the adjustable wheel assembly 50 extends a length from its telescopic engagement with the second end 13 of the support pole 14 , thereby supportably lifting the front portion 36 of the support base 12 from frictional engagement with the playing surface 26 . In one presently preferred embodiment, the adjustable wheel assembly 50 comprises a caster 52 operably disposed in relation to a support assembly comprising a slider 64 having a dimensional length sufficient for selectively extending from a hollow channel formed at the second opposing end 13 of the support pole 14 when the engaging member 22 is positioned in the extended position. In structural relationship, the engaging member 22 preferably includes a cam adjustment surface 74 designed to rest upon a follower 68 that is operably attached to the slider 64 approximate a leading end thereof. In operation, the rotational position of the cam adjustment surface 74 determines the vertical positioning of the follower 68 along its length and therefore the corresponding vertical positioning of the slider 64 relative thereto, as best illustrated in FIG. 4 and 5 . [0065] In one presently preferred embodiment of the present invention, the caster 52 engages a swivel base 82 rigidly connected to the leading end of the slider 64 . The operable relationship between the caster 52 and the swivel base 82 supports multiple directions of movement so that the front portion 36 of the support base 12 can be oriented in a lateral direction by manual manipulation of the distal end 23 of the engaging member 22 (e.g., which preferably provides a handle for gripping by a user). Maneuvering the basketball goal system 10 by selectively positioning of the engaging member 22 in the extended position and thereby disposing the caster 52 of the adjustable wheel assembly SO in supportable relationship with the playing surface 26 is thus intuitive and simple. [0066] Preferably, the caster 52 is rotatably mounted at the leading end of the slider 64 of the adjustable wheel assembly SO. The caster 52 may comprise any configuration that permits rolling in several different directions. In one presently preferred embodiment of the adjustable wheel assembly SO, the caster 50 comprises a swivel base 82 affixed to the slider 64 to permit a full 3600 of rotation about the axis of the support pole 14 . An extension plate 84 may be mounted vertically, extending outwardly from engagement with the swivel base 82 to retain the caster 52 via an axle 86 . The caster or wheel 52 is preferably horizontally displaced from the axis of the support pole 14 , so that the caster 52 will align itself with a direction of motion of the front portion 36 of the base support 12 . Thus, a user may pull on the distal end 23 of the engaging member 22 to move the basketball goal system lain a forward direction or, in the alternative, a user may apply a pushing force against the distal end 23 of the engaging member 22 to rotate the caster 52 and thereby induce lateral movement in the front portion 36 of the support and, accordingly, cause controlled movement of the basketball goal system 10 from a first location to second location. [0067] In one presently preferred embodiment, the caster 52 may be configured to extend directly from the second end 13 of the support pole 14 so as to directly bear the weight of the pole 14 . It will be appreciated, however, that the caster 52 may be formed off-set the support pole 14 in such a manner so as to sufficiently support the weight of the support pole 14 and the front portion 36 of the support base 12 supportably lifted from engagement with the underlying playing surface 26 . It is intended, therefore, that the example provided herein be viewed as exemplary of the principles of the present invention, and not as restrictive to a particular structure for implementing those principles. [0068] Referring to FIG. 4 , a cross-sectional side view of the front portion 36 of the support base 12 of the basketball goal system 10 is illustrated as defined along lines “ 4 - 4 ” of FIG. 1 . As shown, a receiving aperture 28 is preferably formed in the front portion 36 of the support base 12 and includes an internal periphery having a dimensional size and configuration sufficient to accommodate the second end] 3 of the support pole] 4 in fixed or pivotal engagement with the support base 12 . The receiving aperture 28 may be formed separate from an internal cavity 60 also formed in the support base 12 . The internal cavity 60 preferably comprises an internal dimensional periphery sufficient for holding a ballast material, as discussed above. [0069] In one presently preferred embodiment, the support pole 14 pivotally engages the support base 12 by means of a shaft 66 that preferably extends into the support base 12 on either or both sides of the second end 13 of the support pole 14 . The shaft 66 may terminate at one or both ends in a locking pin or shaped cap segment (not shown) designed to fit within a corresponding receiving slot (not shown) integrally formed in the front portion 36 of the support base 12 to restrict pivotal motion of the support pole 14 about the shaft 66 . The receiving slot may be open on the upper surface 40 of the support base 12 to permit easy assembly of the pole 14 and the base 12 by way of introducing the shaft 66 into the receiving slot (not shown). The proximal end 21 of the engaging member 22 may also be pivotally mounted on the shaft 66 , but is free to pivot about the shaft 66 independent the pivotal relationship of the support pole 14 . [0070] It will be appreciated that a follower 68 may be supportably mounted on one or both sides of the slider 64 to provide structural support between the support base 12 and proximate end 21 of the engaging member 22 when the basketball goal system 10 is being moved from one location to another. Moreover, the follower 68 may take any form or configuration suitable for variably engaging the contoured cam adjustment surface 74 of the engaging member 22 . A simple smooth, rounded projection or knob may form the follower 68 ; however, in one presently preferred embodiment, a bearing 70 may be rotatably mounted on a hub 72 to provide smooth motion with a minimum of wear. As best illustrated in FIGS. 4 and 5 , the outer contacting edges of the follower 68 engage the cam adjustment surface 74 formed at the proximal end 21 of the engaging member 22 . The cam adjustment surface 74 preferably takes the form of a cam shaped to push the follower 68 to an extended position when the extending member 22 is positioned in the extended position, wherein the distal end 23 thereof is situated substantially outward and at an angle from the pole support 14 , as best illustrated in FIG. 4 . [0071] Referring specifically now to FIG. 5 , the cam adjustment surface 74 is reoriented to structurally encourage the slider 64 substantially outward a length from the second end 13 of the support pole 14 via the engagement between the follower 68 and the cam surface 74 . As appreciated, the cam adjustment surface 74 must be properly contoured to ensure that a substantially consistent downward force on the follower 68 is maintained through the entire range of motion of the engaging member 22 . [0072] Referring back to FIGS. 4 and 5 , a first structural stop 80 may be formed at the proximate end 21 of the engaging member 22 to engage the follower 68 and thereby provide a form of “capture” to prevent further extension of the engaging member 22 when positioned in the fully extended position. Alternatively, the engaging member 22 may function without the first structural stop 80 and thus permit the engaging member to extend into a near horizontal position, if desired. A second structural stop 81 may be formed at the proximate end 21 of the engaging member 22 to engage the follower 68 and thereby provide a form of “capture” to prevent further extension of the engaging member 22 when disposed in the fully retracted position. [0073] Consistent with the foregoing, the present invention provides a novel basketball goal system 10 having a support base 12 which is moveable without having to physically tilt the support base 12 and thereby support a significant portion of the overall weight of the basketball goal system 10 . By selectively retracting the caster 52 of the adjustable wheel assembly 50 from supportable contact with the playing surface 26 , maneuverability and operation of the support base 12 are facilitated and safety is therefore increased. The pivoting engaging member 22 serves to thereby restrict movement of the support base 12 by preventing contact of the caster 52 with the playing surface 26 . Moreover, the engaging member 22 may provide a handle to assist in movement of the basketball goal assembly 10 and a rebound surface for the basketball during game play, if desired. [0074] Stability of the basketball goal system 10 during play is improved by selectively maintaining a substantial portion of the contacting surface 38 of the support base 12 in frictional contact with the playing surface 26 for game play. Movement of the basketball goal system 10 from one location to another is further simplified by the use of an adjustable wheel assembly 50 operably disposed in extendable relation to the second end 13 of the support pole 14 engageably received at the front portion 36 of the support base 12 . The adjustable wheel assembly 50 comprises a caster 52 connected to a swivel base 82 which, in combination, permits the lateral movement of the front portion 36 of the support base 12 when the extending member 22 is positioned in the extended position. The incorporation of one or more rollers 44 in concert with the adjustable wheel assembly 50 facilitates controllable maneuverability of the basketball goal system 10 of the present invention from one location to another location. Moreover, the linear path of extension and retraction of the slider 64 and the caster 52 of the adjustable wheel assembly 50 enables supportable deployment of the caster 52 in relation to the playing surface 26 without substantially moving the basketball goal system 10 , so that easy adjustments are possible. [0075] In addition, the structural arrangement of the cam adjustment surface 74 and the follower 68 has a number of operative benefits. For example, the leverage involved enables a user to lift the considerable weight of the front portion 36 of the support base 12 (i.e., over an inch or more) with a comparatively small downward force acting on the engaging member 22 . The cam adjustment surface 74 and the follower 68 are also enclosed within the receiving aperture 28 , so that fingers or other extremities of a user may not be easily pinched, and no significant part protrudes horizontally outward from the support base 12 in any configuration so as to injure a user or impede storage of the basketball goal system 10 . [0076] The telescopic engagement between a length of the slider 64 and the second end 13 of the support pole 14 also imparts a number of distinct advantages to the present invention. For example, the mounting of the caster 52 on the slider 64 selectively disposed within hollow channel formed in the support pole 14 provides a more rigid connection than a fixture attached to a polymeric material, such as plastic, which may be used to form the support base 12 . This structural arrangement between the caster 52 and the slider 64 of the adjustable wheel assembly 50 with the support pole 14 provides a sturdier basketball goal system 10 in which the greatest loads are carried by stronger, more rigid members. Manufacturing and assembly of the basketball goal system 10 is also simplified by reducing the number of metal fixtures that must be mounted in relation to the support base 12 to retain metal parts. Consequently, the basketball goal system 10 of the present invention may be manufactured with comparatively little expense and difficulty. [0077] The present invention may be embodied in other specific forms without departing from its structures, methods, or other essential characteristics as broadly described herein and claimed hereinafter. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope. [0078] Another presently preferred embodiment of the present invention, designated generally at 110 , is best illustrated in FIGS. 6 and 7 . As shown, the basketball goal assembly 110 comprises a support base 112 having a top surface 114 , a bottom surface 116 , a front end 118 , and a rear end 120 . The support base 112 rests on a generally horizontal playing surface and is configured to support the additional members of the basketball goal assembly 110 . [0079] In one presently preferred embodiment, the support base 112 is formed of a substantially sturdy, rigid material. For example, the support base 112 may be formed of a polymeric material such as, for example, a low-density linear polyethylene. It will be readily appreciated by those skilled in the art, however, that a wide variety of other suitable materials such as wood, fiberglass, ceramic, any of numerous organic, synthetic or process materials which are mostly thermoplastic or thermosetting polymers of high molecular weight, and/or other composite or polymeric materials are possible which are consistent with the spirit and scope of the present invention. [0080] The basketball goal assembly 110 further comprises an engaging member 122 having first and second ends 124 and 126 . In one presently preferred embodiment, the engaging member 122 generally tapers in width from the first end 124 as it extends towards the second end 126 . The first end 124 of the engaging member 122 is pivotally connected to the front end 118 of the support base 112 . This allows the engaging member 122 to pivot between the playing position as shown in FIG. 6 and the extended position as shown in FIG. 7 . [0081] As with the support base 112 , in one presently preferred embodiment of the present invention, the engaging member 122 is formed of a substantially sturdy, rigid material. For example, the engaging member 122 may be formed of a polymeric material such as, for example, a low-density linear polyethylene. It will be readily appreciated by those skilled in the art, however, that a wide variety of other suitable materials such as wood, fiberglass, ceramic, any of numerous organic, synthetic or process materials which are mostly thermoplastic or thermosetting polymers of high molecular weight, and/or other composite or polymeric materials are possible which are consistent with the spirit and scope of the present invention. [0082] In the playing position, the engaging member 122 extends in a generally upward direction relative to the support base 112 . The engaging member 122 is configured and disposed relative to the support base 112 such that when the engaging member 122 is selectively positioned in the playing position the first end 124 of the engaging member 122 contacts the playing surface. Contacting the playing surface thereby restricts movement of the support base 112 , as will be discussed in further detail below. In one presently preferred embodiment of the present invention, the engaging member 122 includes a second end 126 having one or more extended portions 130 . The extended portions 130 form a recess 132 through which the front end 118 of the support base 112 may at least partially extend. The extended portions 130 are configured to contact the playing surface when the engaging member 122 is in the playing position. [0083] Upon assembly, a support pole 128 is inserted into a receiving aperture (not shown) that is formed in the support base 112 such that the support pole 128 is retained in a substantially vertical orientation in relation to the base 112 . As appreciated, the support pole 128 is sufficiently secured in the receiving aperture of the base 112 to maintain the disposition of the pole 128 . The support pole 128 serves to support a basketball goal assembly 129 in relation to the playing surface. In one presently preferred embodiment of the present invention, the engaging member 122 may be configured with a recess 134 which receives at least a portion of the pole 128 when the engaging member 122 is disposed in the playing position. [0084] In the playing position, the engaging member 122 operates to restrict the movement of the support base 112 by supportably contacting the playing surface. Functionally, the engaging member 122 further serves to provide a rebound surface for a basketball during game play of shooting baskets. In addition, the engaging member 122 may provide protection for the securement of the pole 128 in the receiving aperture and function as a support to the pole 128 by means of engaging the pole 128 , as will be explained in further detail herein below. [0085] With reference to FIG. 7 , the basketball goal assembly 110 is shown with the engaging member 122 pivoted into the extended position. The extended position is defined herein as a position where the first end 124 of the engaging member 122 is not in contact with the playing surface. Specifically, the extended portions 130 of the engaging member 122 are no longer disposed in restrictive contact with the playing surface such that the support base 112 may be moved to another location, if desired. [0086] In the extended position, the engaging member 122 may serve as a lever or handle to allow manual movement of the support base 112 . In one presently preferred embodiment, the engaging member 122 is further configured with one or more handles 136 on the second end 126 . The handles 136 serve to facilitate manual manipulation of the engaging member 122 . [0087] With reference to FIG. 8 , another perspective view of the basketball goal assembly 110 is shown with the engaging member 122 disposed in the playing position. In one presently preferred embodiment, the second end 126 of the engaging member 122 is configured with a recess to receive and engage at least a portion of the length of the support pole 128 . The engaging member 122 may further comprise a removable fastener disposed on the second end 126 to secure the engaging member 122 to the pole 128 when in the playing position. One of skill in the art will appreciate that the removable fastener may include one or more clamps, pins, collars or the like. [0088] In one presently preferred embodiment, the removable fastener may comprise a pair of brackets 138 formed adjacent the second end 126 of the engaging member 122 , as best shown in FIG. 8 . When in the playing position, the support pole 128 is generally disposed between the brackets 138 . A retaining pin 140 may be introduced through a slot formed in the support pole 128 and supported to thereby selectively secure the engagement of the engaging member 122 to the pole 128 . This engagement prevents unexpected movement of the engaging member 122 during game play and thus retains the engaging member 122 in the playing position. In an alternative embodiment, the engaging member 122 , when secured to the pole, provides additional structural support to the pole 128 . [0089] Still referring to FIG. 8 , a removable cap 144 is shown disposed at the back end 120 of the support base 112 . The cap 142 serves to allow the insertion or removal of a ballast material into an internal cavity formed in the support base 112 . With reference to FIG. 9 , the support base 112 is shown without the engaging member 122 . In one presently preferred embodiment of the present invention, the support base 112 has an internal cavity 146 for receiving a ballast weight such as, for example, water, sand, or the like. The ballast weight provides support to the basketball goal assembly during rigorous game play. In such an embodiment, the support base 112 is configured with an opening 148 near, but spaced from, the top surface 114 of the support base 112 such that when the base 112 is filled with water to the point that the water level in the support base 112 reaches the opening 148 , a void remains within the top of the cavity 146 which does not fill with water. This is to allow expansion of the water in the case of freezing temperatures. [0090] In operation, after introducing the ballast material into the internal cavity 146 of the support base 112 , the cap 144 may be secured into the opening 148 to prevent the displacement of the ballast material from the base 112 . As will be appreciated, the support base 112 may alternatively forgo the use of a cavity 146 and comprise sufficient weight to act as ballast in order to ensure the stability of the basketball goal assembly 110 . [0091] With reference to FIG. 10 , the bottom surface 116 of the support base 112 is shown. Preferably, the support base 112 comprises a roller 150 disposed in supportable relation to the support base 112 adjacent to the front end 118 of the base 112 . The roller 150 is capable of supporting the effective weight of the support base 112 to thereby maneuver the base 112 from place to place. In one presently preferred embodiment, the roller 150 comprises a single roller extending a sufficient length across the width of the support base 112 to allow maneuvering of the base 112 . Alternatively, the roller 150 may comprise two or more rollers 150 for supporting the support base 112 . The roller 150 may be embodied as a cylindrical wheel or a caster. One of skill in the art will readily appreciate that various embodiments of the roller 150 are possible and are intended to be included within the scope of the present invention. [0092] The support base 112 may include a caster 152 disposed in relation to the bottom surface 116 of the base 112 at a spaced apart distance from the roller 150 . The caster 152 serves to provide additional support to facilitate maneuvering of the support base 112 when disposing the engaging member 122 in the extended position. In one presently preferred embodiment, the caster 152 may be disposed at an intermediate position between the front and back ends 118 , 120 of the support base 112 to better balance the weight between the roller 150 and the caster 152 . [0093] Referring again to FIG. 10 , the support base 112 may include a shaft 154 (shown in phantom) that preferably extends across at least a portion of the width of the base 112 and is operably secured to the engaging member 122 at its first end 124 . The shaft 154 supports the engaging member 122 and provides an axle about which the engaging member 122 can pivot between the playing position as shown in FIG. 6 and the extended position as shown in FIG. 7 . [0094] In the presently preferred embodiment illustrated in FIG. 10 , the shaft 154 extends into the extended portions 130 of the support base 112 . In an alternative preferred embodiment, the shaft 154 may comprise two portions with each portion separately secured to the engaging member 122 and the support base 112 . In yet another alternative embodiment, the shaft 154 may extend through the roller 150 and provide a supporting axle to the roller 150 . [0095] With reference to FIG. 11A , a side view of the basketball goal assembly 110 is shown with the engaging member 122 in the playing position. The engaging member 122 is configured and disposed in relation to the support base 112 such that when in the playing position the first end 124 of the engaging member 122 contacts the playing surface 156 to prevent movement of the basketball goal assembly 110 . In a presently preferred embodiment, the extended portions 130 of the engaging member 122 contact the playing surface 156 , as best shown in FIG. 6 . The engaging member 122 contacts the playing surface 156 and thus prevents contact between the roller 150 and the playing surface 156 . This effectively renders the roller 150 inoperable and prevents movement of the support base 112 . [0096] In an embodiment utilizing the caster 152 , contact between the caster 152 and the playing surface 156 is maintained. The support base 112 may be slightly tilted by the engaging member 122 such that a portion of the support base 112 adjacent the back end 120 contacts the playing surface 156 . This contact prevents a further restriction to movement. [0097] With reference to FIG. 11B , a side view of the basketball goal assembly 110 is shown with the engaging member 122 in the extended position. In this position, the engaging member 122 is not in contact with the playing surface 156 . Thus, the roller 150 , as well as the caster 152 , remains in contact with the playing surface 156 . In the extended position, the support base 112 may then be maneuvered to another location, as desired. The second end 126 of the engaging member 122 may be used to guide and otherwise maneuver the support base 112 to the new location. [0098] With reference to FIG. 12 , the engaging member 122 is shown in the extended position wherein being disposed in a generally horizontal position relative to the support base 112 to accommodate for compact storage of the support base 112 and the engaging member 122 after removal of the support pole 128 . In such a position, the basketball goal assembly 110 is suitable for storage or shipping. [0099] As disclosed herein, the present invention provides a novel two-part support base for a basketball goal assembly 110 having a support base 112 which is readily moveable without having to physically tilt the base 112 and thereby support a significant portion of its weight. By manually maintaining contact between the first end 124 of the engaging member 122 with the playing surface 156 , movement of the support base 112 is facilitated and safety is therefore increased. The pivoting engaging member 122 serves to thereby restrict movement of the support base 112 by preventing contact of the roller 150 with the playing surface 156 . Moreover, the engaging member 122 may provide a handle to assist in movement of the basketball goal assembly 110 , a rebound surface for the basketball during game play and a protective shield to protect the securement of the support pole 128 in relation to the support base 112 , if desired. [0100] The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

A portable basketball goal system having an adjustable wheel assembly is disclosed. The portable basketball goal system may comprise a rigid pole, a support base, an adjustable wheel assembly, and an engaging member. The support base is configured to maintain the rigid pole in a generally elevated position. The adjustable wheel assembly is connected to the support base and has an engaged and disengaged position. In the engaged position, the wheel assembly supportably engages a playing surface. In the disengaged position, the wheel assembly may not supportably engage the playing surface. The adjustable wheel assembly may be slidably coupled to the support base. The adjustable wheel assembly may be operated by an engaging member coupled to a cam surface. The cam surface may interact with a follower to transition the adjustable wheel assembly between the supportable and unsupportable engagements.

BACKGROUND OF THE INVENTION This invention relates to divider systems for use in offices, and specifically to a partition interconnection device which is used with office divider partitions. In the field of office furniture it is common for large amounts of office space to be subdivided into cubicles by the use of divider panels which can be interconnected in a multitude of combinations in order to subdivide a large office space into individual, door-less offices. Typically, such divider panels are approximately six feet high and are not only utilized for subdividing the office space, but also for providing channels for holding electrical wiring, telephone wires and computer cables. In addition to providing thoroughfares for cabling, office panels also must provide means for supporting shelves and bookcases and attachments of modular office furniture such as desks and other cabinetry. Further, office partition devices must be structurally stable and securely interconnect in order to avoid wobbling after being assembled. In the usual office circumstance, the assembled divider panels are viewed as structurally sound walls by the typical office user and, therefore, the connected panels must be capable of withstanding the jolt of office personnel leaning against the panels and bumping against the panels and generally utilizing the divider panel wall as they would a permanent wall structure. As office divider panels are intended to be temporary structures which may be disassembled and reconfigured on demand of the user, it is important that the interconnection between office panels be easily assembled and disassembled while providing a strong secure connection between panels. An additional desirable feature of such office panels is that the means for connecting the panels be concealed so that the means for fastening the panels together does not detract from the overall appearance of the partition system. Further, it is important that the means for connection be flush with the panel surfaces so that fastener protrusions do not exist to catch clothing of personnel as they pass by the panels. It is another important requirement of office partition interconnection devices that they provide a means for connection of the office furniture and accessories which is easily accessible and yet can be concealed when not in use. In addition, it is necessary that the means for attachment of office accessories such as cabinetry, desks, and shelves provide strong, secure attachment and support of the accessories. In addition, it is important that the means for attaching accessories allow the positioning of the accessories at any selected height between the top of the partition and the bottom. It is a further requirement of such office partition systems that the means for connecting panels together avoid interference with the channels provided for running of cables as well as avoiding interference with the means provided for attachment of accessories. Y Yet another consideration in the design of such office divider panels is that the means for connecting office panels or for connecting accessories does not require the panel assembler to lift a panel in order to engage a first panel with a second panel during the interconnection. As office partition panels are generally reasonably heavy items, it is not only difficult to lift the panels, but it is also difficult to guide such weighty items into connecting slots affixed to an adjoining panel. Another feature of importance in office panel connection devices is that the means for interconnecting panels permit the insertion or removal of a single panel from a row of panels without requiring disassembly or manipulation of adjoining panels which previously have been implaced and which may have substantial amounts of office furniture and accessories attached thereto. SUMMARY OF THE INVENTION The invention provides for a means of interconnection of office partition panels which permits the joining of office panels by abutting the ends of the panels and then sliding the panels laterally to interlock the abutted ends of the panels. A securing means in the form of a set screw is then tightened to fix the interconnected panels in place. The interconnection between panels is made such that a vertical channel is provided for passage of cables vertically between two interconnected panels while also providing a channel for attachment of accessories and components at any height along the panel. Therefore, it is an object of the present invention to provide a means for interconnection of office partitions which avoids the need to lift entire panels in order to engage and connect a first panel with the second panel. Another object of the present invention is to permit interconnection of office partition panels while providing a vertical cable channel between two adjoining panels. Yet another object of the present invention is to provide a means for interconnection of two partitions or office divider panels which provides a means for attachment of office accessories and components at any height along the point of interconnection between two adjacent panels. Another object of the present invention is to provide a sturdy, easily assembled interconnection between office panels which is stable and secure and resists flexing of the joint between two abutting office partition panels. Yet another object of the present invention is to allow the removal of an office partition panel from its connection with the panels at either end without disturbing the panels adjoining the one to be removed. The foregoing and other objects are not meant in a limiting sense, and will be readily evident upon a study of the following specification and accompanying drawings comprising a part thereof. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a from and right side exploded perspective fragmentary view of the inventive office panel interconnect device attached to two adjacent partition panels; FIG. 2 is a top plan view of an assembled panel interconnect device joining two end abutting office partition panels; FIG. 3 is a top plan view of the panel end plate for attachment to an office partition panel with the connection shoe aligned for attachment thereto; FIG. 4 is a top plan view of an alternative embodiment of the panel end plate of FIG. 3 in which two panel end plates are joined orthogonally to permit the right angle connection of two office divider panels having panel end plates mounted thereon; FIG. 5 is a top plan view of an alternative arrangement of the panel end plates of FIG. 3 in order to permit the connection of four office panels having panel end plates thereon about a single point. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. 1, an embodiment of the present invention 10 is shown in exploded view. In general, the invention is comprised of panel end plates 14a, 14b, which are affixed to office-type partition panels 12a, 12b. Partition panels 12a, 12b are then secured together by the interconnection of panel end plates 14a, 14b with connection shoe 15. When it is desired to interconnect office panels, panel end plate 14a, 14b is attached to the entire vertical length of the facing ends of the selected panels. Panel end plates 14a, 14b may be attached by fasteners to the office divider panels or may be manufactured concurrently with each panel. After the attachment of panel end plate 14a, 14b, connection shoe 15 is interposed between panel end plate 14a and panel end plate 14b and is utilized to interconnect the panels 12a, 12b. Referring now to FIG. 2, the resulting interconnection of divider panels 12a and 12b by an embodiment of the present invention is shown. It may be seen in FIG. 2 that a tight, complete and structurally sound connection between panels 12a and 12b is provided by the present invention. Also shown in FIG. 2 is cable duct 24a, 24b which is provided by the present invention for passage of electrical wiring and computer cables and the like, upwardly or downwardly between panels 12a, 12b. Once panels 12a and 12b are interconnected by connection shoe 15 engaging end plates 14a, 14b, a securing means is utilized to secure the components together and prevent separation of panels 12a, 12b. In the present embodiment, set screws 26a, 26b are tightened against interlocking flanges 33, 42 (FIGS. 2&3) of panel end plates 14a, 14b and connection shoe 15. Referring now to FIG. 3, the components of end plates 14 (14a, 14b of FIG. 1 ) will be further described. Panel end plate 14 is comprised of base plate 30 which extends along the entire face of the end of an office partition panel. Base plate 30 may be constructed with a panel, if desired, or may be attached to an existing panel through the use of conventional fasteners such as screws, bolts or glue. At either edge of base plate 30 are accessory connection channels 32a, 32b. Accessory connection channels 32a, 32b permit attachment of office accessories to the panels at any vertical height. An accessory bracket adapted for insertion into channels 32a, 32b (not shown) may be introduced into accessory channel 32a, 32b and fixed in place to permit the attachment of office components thereto or, alternatively, office accessories having mounting brackets which are compatible with accessory channels 32a, 32b can be used. In either case, when the accessory bracket is positioned at the selected height within accessory channel 32a, 32b it is fixed in place utilizing a fastener such as set screws 26a, 26b which secure the panels with connection shoe 15. The fastener provides compression capture of the bracket in channel 32a, 32b. When accessory channel 32a, 32b is not being used for the connection of office components, it may be concealed by placing a covering over the channel. Referring again to FIG. 2, such a covering may be seen in the form of channel cover 28. Channel cover 28 may be made of any suitable pliable material such as plastic. Channel cover 28 is press fitted into accessory channel 32a, 32b. Cover 28 may be in the form of a T or may have individual legs as shown in FIG. 2 which are captured by bead 35 of accessory channel 32a, 32b. Referring to FIGS. 3 the means for interconnection of panel end plate 14a, 14b with connection shoe 15 will be discussed. Panel end plate connection flanges 33 extend from base plate 30 of panel end plate 14 and are slightly laterally spaced from the center longitudinal axis of end plate 14a, 14b. Flanges 33 are comprised of legs 36 and arms 37. Arms 37 are registerably engageable with arms 47 of similarly shaped flanges 42 which extend from either side of shoe 15. Flanges 42 of shoe 15 are also comprised of legs 46 and arms 47. Legs 36 of flanges 33 and legs 46 of shoes flanges 42 are spaced outwardly from panel end plate 14a, 14b and shoe spine 44 in order to provide cable duct void 24 (FIG. 2) when end plate flanges 33, are connected with flanges 42 of shoe 15. Referring now to FIG. 3, it may be seen that connection shoe 15 is provided with flanges 42 which are similarly shaped to those of panel end plate flanges 33 for registerable connection therewith. Shoe flanges 42 are spaced outwardly from shoe spine 44 in order to create cable duct void 24a, 24b which exists between base plate 30 of panel end plate 14a, 14b and shoe spine 44 of connection shoe 15 when shoe 15 and end plates 14a, 14b are interconnected. Still referring to FIG. 3, it may be seen that connection shoe 15 is provided with flanges 42 on either side of shoe spine 44. However, flanges 42 of either side are offset with respect to flanges 42 of the opposing side so that as shoe 15 is interconnected with panel end plate 14a, 14b (FIG. 2), alignment of the outside edges of panel end plates 14a, 14b occurs and the outside surface of the panels are aligned and flush with one another. The offset configuration of flanges 42 of connection shoe 15 permits engagement of flanges 33 on panel end plate 14 when panel end plate 14 approaches connection shoe 15 from either the right or left hand side. This allows manufacture of a single configuration of panel end plate 14a, 14b for use with connection shoe 15. Referring now to FIG. 4, an alternative embodiment of panel end plate 14 (FIG. 3), is shown wherein two panel end plates 52, 53 have been joined at a right angle to one another in order to create a panel end plate 50 for use in connecting two office partition panels at a right angle to one another. Right angle end plate 50, while being of unitary construction, is essentially two panel end plates 14, as shown individually in FIG. 3, which have been joined at a right angle to one another and having additional support bridging the hypotenuse in the form of back plate 54. Right angle end plate 50 is used in situations in which two office panels are joined to form a comer of a right angle. Referring now to FIG. 5, an alternative embodiment of panel end plate 14a, 14b (FIG. 1) is shown. Center post plate 60 is a configuration of multiple end plates 14 as shown in FIG. 3 and may be used for the connection of three office partition panels into a "T" shape or for the interconnection of four office panel partitions all at right angles to their adjacent office panel partitions. The embodiment shown in FIG. 5 is of unitary construction for ease of manufacture, however, it will be appreciated by those skilled in the art, that right angle connecting rods could be used to connect four of the single end plates 14 shown in FIG. 3 to achieve the same functional considerations as the unitary device of FIG. 5. In use center post plate 60 is attached to a panel end plate 14a or 14b (FIG. 1) at position 62a-d of center post plate 60 in the manner previously described for the abutting panel end plates 14a, 14b of FIG. 2. Afterward, with center post plate 60 supported by a first office partition panel, other office partition panels may be attached as desired at the remaining available positions 62a-62d of post plate 60. Certain changes may be made in embodying the above invention, and in the construction thereof, without departing from the spirit and scope of the invention. It is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not meant in a limiting sense. It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween Particularly, it is to be understood that in the claims, ingredients or compounds recited are intended to include compatible mixtures of such ingredients.

A device for interlocking office divider panels is provided which permits the connection of office divider panels while providing for a cable duct between panels and the mounting of office accessories at any height of the panel and while permitting the assembly of panels without the need to lift office panels and while permitting the removal of a single panel without disturbing the adjoining office divider panels.

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation application of U.S. patent application Ser. No. 09/992,359, now issued U.S. Pat. No. 6,689,047, filed on Nov. 14, 2001, which claims benefit of and priority to U.S. provisional patent application Ser. No. 60/248,808, filed on Nov. 15, 2000, the entire disclosures of which are incorporated by reference herein. TECHNICAL FIELD The present invention relates to devices and methods for treating urinary incontinence, such as urinary incontinence in women resulting from intrinsic sphincter deficiency. BACKGROUND INFORMATION Urinary incontinence is a widespread problem throughout the world. Urinary incontinence affects people of all ages and can severely impact a patient both physiologically and psychologically. One form of urinary incontinence suffered by women is intrinsic sphincter deficiency (ISD), a condition in which the valve of the urethral sphincter does not function properly, thus preventing proper coaptation of the urethra. Without proper coaptation, a person is unable to control urinary leakage. ISD can arise from loss of urethral vasculature, thinning of urethral mucosa, loss of the urethral connective tissue elements, neurologic compromise of the sympathetic smooth muscle, or compromise of the external striated sphincter. Another form of urinary incontinence is known as bladder neck hypermobility. Bladder neck hypermobility can arise from loss of support by the pelvic floor and loss of suspension by the pelvic connective tissue in ligaments and fascia. In this condition, the bladder neck and proximal urethra descend in response to increases in intra-abdominal pressure, resulting in uncontrollable urinary leakage. Common approaches to treating urinary incontinence in women require invasive surgical procedures either through the vaginal wall or the abdominal wall. These surgical procedures focus on elevating the urethrovesical junction by introducing a sling that passes to the posterior side of the urethra and suspending the urethra from an anatomical structure located anterior to the urethra, for example, the abdominal fascia, the pubic bone, or the Cooper's ligament. Surgical treatments of urinary incontinence that use slings typically involve placing the sling under the urethra to provide suburethral support. Slings of this type simultaneously compress and suspend the urethra to treat urinary incontinence. One disadvantage of these procedures is the invasive nature of these procedures. Another disadvantage is that weight gain or loss can affect the suspension of the urethra causing it to become too tight or too loose. Still another disadvantage is that some types of slings may shrink with age and may cause difficulties with voiding. Other invasive surgical approaches to treating urinary incontinence include the use of vaginal wall slings and/or artificial urinary sphincters. Periurethral injection (PI) of biocompatible bulk-enhancing agents, another approach to treating urinary incontinence, has the advantage of being a less invasive form of treatment and, thus, can be performed on an outpatient basis. PI uses bulk-enhancing agents, such as, Teflon® (DuPont), autologous fat, and collagen, to increase pressure on the urethra and reduce the size of the urethral lumen, providing additional resistance to the flow of urine. Such injections may be accomplished either transurethrally or periurethrally. Typically, however, repeat treatments of PI are required because the bulk-enhancing agent can be absorbed by the body or translocated from the site of injection. Another drawback to PI is that accidental over-bulking may result in undesirable urinary retention requiring catheterization to void until the injectant is absorbed by the body. SUMMARY OF THE INVENTION The present invention relates to a treatment for urinary incontinence without drawbacks associated with more invasive surgeries or PI. The invention generally involves coapting a urethra externally between a sling and a vaginal wall. The term “urethra,” as used herein, generally includes the bladder neck. Because of the minimally invasive nature of the invention, a procedure according to the invention can be performed in conjunction with other transvaginal procedures. In addition, such a procedure can quickly and easily be reversed as the sling may be held in place by removable securing devices such as sutures or surgical staples. In one aspect, the invention features a surgical device for treating urinary incontinence that includes a curved needle, a dilator, and a sling. A distal end of the dilator is coupled to a proximal end of the curved needle, and a distal end of the sling is coupled to a proximal end of the dilator. In some embodiments, the curved needle includes a curvature sufficient to allow the needle to enter the body from the vaginal cavity and through the vaginal wall, pass to one side of the urethra, continue over an anterior side of the urethra, and exit the body on the other side of the urethra. The dilator generally can be any shape in which the distal end is tapered and the proximal end can create an opening to accommodate a sling as it follows the dilator into the body. In some embodiments, the dilator can be substantially flat and triangular in shape. In other embodiments, the dilator can be substantially rectangular and tapered at the distal end. The dilator can be made from one or more biocompatible materials such as a plastic or metal. The dilator can also include markings to indicate the location of the sling within the body. The sling can be made of one or more biocompatible materials selected from the group consisting of a natural material, a synthetic material, or a combination of a natural material and a synthetic material. The sling can be about 0.5 cm to about 4 cm in width. In a particular embodiment, the sling is about 1 to about 3 cm in width. In another particular embodiment, the sling is about 1.5 to about 2.5 cm in width. In some embodiments, a tether couples the curved needle to the dilator. Examples of the form the tether may take includes a wire, a suture, and a portion of the sling. In some embodiments, a first portion of the sling can be smaller in width than a middle portion of the sling. In a particular embodiment, the first portion of the sling can couple the sling to the dilator. In another particular embodiment, the first portion of the sling can couple the dilator to the needle. In some embodiments, a pouch can be fixedly attached to the dilator and releasably attached to the sling. In other embodiments, the surgical device can include a stiffener to maintain the sling in a generally planar orientation as it enters the body. In another aspect, the invention features a surgical device that includes a sling, a first tether with a proximal end coupled to a distal end of the sling, a second tether with a distal end coupled to a proximal end of the sling, a curved needle coupled to a distal end of the first tether, and a dilator disposed along the first tether between the curved needle and the distal end of the sling. In yet another aspect, the invention features a method of treating urinary incontinence. The method includes introducing a sling into a body and positioning the sling on an anterior side of the urethra to coapt the urethra against the vaginal wall. The sling can be introduced into the body via the vaginal cavity and through the vaginal wall. In some embodiments, the sling is positioned to surround less than 360° of the circumference of the urethra. In some embodiments, the sling is positioned to surround approximately 180° of the circumference of the urethra on an anterior side of the urethra. In other embodiments, the sling is positioned to surround approximately 90° to approximately 180° of the urethra on the anterior side of the urethra. In some embodiments, a surgical device according the invention is introduced into the body via the vaginal cavity and through the vaginal wall to pass to one side of the urethra, and then pass about the anterior side of the urethra, and to exit the body on the other side of the urethra into the vaginal cavity. The surgical device can include a curved needle, a dilator, and a sling, and the sling can be positioned in the body to coapt the urethra to an anterior portion of the vaginal wall in the body. In some embodiments, the anterior of the urethra is separated from surrounding tissue, for example, the bladder. The separating step can be performed, for example, by using hydrodissection or balloon dissection. In still another aspect, the invention features a method of treating urinary incontinence. The method includes introducing a surgical device into a body via the vaginal cavity. The surgical device can comprise a sling, including a distal end and a proximal end, and a first tether, including a distal end and a proximal end, wherein the proximal end of the tether is coupled to a distal end of the sling. The device can also include a second tether, including a distal end and a proximal end, wherein the distal end of the second tether is coupled to a proximal end of the sling. The device can also include a curved needle coupled to the distal end of the first tether and a dilator disposed along the first tether between the curved needle and the distal end of the sling. The curved needle is passed into the body via the vaginal cavity, through the vaginal wall to one side of the urethra, over an anterior portion of the urethra, and out of the body on the other side of the urethra into the vaginal cavity, creating a path for the first tether, the dilator, the sling, and the second tether to follow. The dilator is advanced along the path to position the sling about the urethra, leaving at least a portion of the second tether in the vaginal cavity. The dilator and at least a portion of the first tether exits the body into the vaginal cavity, leaving the sling in place about the anterior portion of the urethra to coapt the urethra to the anterior portion of the vaginal wall. The first tether and second tether are secured to an interior wall of the vaginal cavity. The method can also include separating the anterior portion of the urethra from the surrounding tissue to create a pocket or opening to accommodate the sling. These and other objects, along with advantages and features of the invention disclosed herein, will be made more apparent from the description, drawings, and claims that follow. BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead being placed generally upon illustrating the principles of the invention. FIG. 1 shows a surgical device according to one embodiment of the invention. FIG. 2 shows a surgical device according to one embodiment of the invention. FIG. 3 shows a transverse cross-sectional view of the surgical device of FIG. 2 along section 3 — 3 . FIG. 4 shows a sling according to one embodiment of the invention. FIG. 5 shows a sling according to one embodiment of the invention. FIG. 6 shows a surgical device according to one embodiment of the invention. FIGS. 7A–C show three exemplary embodiments of transverse cross-sectional views of the surgical device of FIG. 6 along section 7 A, 7 B, 7 C – 7 A, 7 B, 7 C. FIG. 8 shows a surgical device according to one embodiment of the invention. FIG. 9 is a schematic diagram of a step in a method according to one embodiment of the invention. FIG. 10 is a schematic diagram of a step in a method according to one embodiment of the invention. FIG. 11 is a schematic diagram of a step in a method according to one embodiment of the invention. DESCRIPTION FIG. 1 depicts a surgical device 10 according to one embodiment of the present invention. FIG. 1 shows a curved needle 20 , a first tether 30 , a dilator 40 , a sling 50 , and a second tether 60 . The curved needle 20 can be any curved needle used to guide the rest of the surgical device 10 around a bladder neck. The needle 20 can be a curved solid needle, a hollow needle, or a channeled needle. The proximal end of the needle 24 can have an eyelet or other attachment structure. The first tether 30 is shown to couple the dilator 40 to the curved needle 20 . The tether 30 can be coupled to the needle 20 by any means including, but not limited to, tying, gluing, looping, crimping, and bonding. The curvature of the needle 20 should be sufficient to pass around a urethra 104 from a vaginal cavity 102 , as shown in FIG. 9 . The needle 20 may be of any size and/or type. For example, the needle 20 may be a ½ circle or a ⅜ circle needle. The needle 20 may be of any point configuration such as a cutting point or a reverse cutting point. The size of the needle 20 may also range from 12 mm–25 mm. Examples of needles 20 include, but are not limited to Ethicon PC-12 and PS-5. (Ethicon, Inc., Somerville, N.J.) The first tether 30 and the second tether 60 can be formed from a suture, a wire, a portion of the sling 50 , or any other material that is strong enough to resist breaking as the surgical device 10 is passed through the body. The tethers 30 , 60 may be attached to the sling 50 in any number of ways known in the art such as tying, suturing, bonding, or molding. The tethers 30 , 60 can also be used to secure the sling 50 in place once it is disposed around the urethra 104 . The sling 50 is secured by the tethers 30 , 60 to the interior portion of the vaginal wall. Typically, the tethers 30 , 60 remaining in the vaginal wall will eventually be covered with endothelial tissue. In some embodiments, the tether 30 , 60 is a suture. The suture can be a non-absorbable suture such as a polyester, for example Dacron® polyester (DuPont, Wilmington, Del.), an expanded polytetrafluoroethylene (EPTFE), such as Gore-Tex® (W.L. Gore & Associates, Inc., Newark, Del.), a polypropylene, or a braided silk. Other suitable materials that can be used as a suture will be apparent to those skilled in the art. The dilator 40 can be made of a semi-rigid plastic material. Examples of such materials include, but are not limited to, polyethylene terephthalate (PET), polyethylene (PB), or ethylene vinyl acetate (EVA). The dilator 40 is sufficiently rigid to push through the tissue of the body and create an opening for the sling 50 , but also sufficiently flexible to curve axially around the urethra 104 , following the path of the curved needle 20 , as shown in FIGS. 9 and 10 . The distal end 42 of the dilator 40 can be substantially similar in size to the proximal end 24 of the curved needle 20 . From the distal end 42 of the dilator 40 , the dilator 40 can expand in a planar direction, a cylindrical direction (i.e., increasing circumference), or combination of both a planar direction and a cylindrical direction. For example, if the dilator 40 expands in a planar direction, the resultant dilator 40 is substantially flat and triangular in shape. The dilator 40 preferably expands until it reaches a size not less than the width of the sling 50 , to ensure that the opening created by the dilator 40 will accommodate the width of the sling 50 . The dilator 40 can terminate at a maximum width, whereby the passage of the dilator 40 through the body creates an opening sufficiently wide to allow the sling 50 to pass through the body. The length of the dilator 40 can be sufficient to allow the dilator 40 to be grasped with forceps and pulled and/or pushed through the body, if necessary. Alternatively, as shown in FIGS. 2 and 3 , the dilator 140 can be extended distally to overlap with or partially enclose the sling 150 . In embodiments where the dilator 140 is further extended, the proximal portion of the dilator 140 can also be used as a stiffener 146 to prevent the sling 150 from rolling or curling. Alternatively, the stiffener 146 may be a separate element from the dilator 140 . The stiffener 146 provides rigidity and prevents distortion of the sling 150 during passage through the patient's body, as well as permitting the dilator 140 to dilate or cut an opening in the patient's body as it passes through the body in the path created by the curved needle 120 . In some embodiments, the curved needle 120 and dilator 140 may be a single unit, for example a curved blade. This single unit may include a sharp point at the distal end to create an incision from which the blade flares out, curving axially along its length, to a maximum width at the proximal end. The dilator 140 and/or the stiffener 146 may also provide a bending effect that permits the sling 150 to follow an axial bend along its length. Finally, the dilator 140 and the stiffener 146 can reduce damage to the sling 150 during handling. The stiffener 146 may be made of the same material or a different material than the dilator 140 . The stiffener 146 may be made of any of a variety of materials compatible with the above-described considerations including, but not limited to, polyethylene, polypropylene, and acrylic. The stiffener 146 may provide approximately 1 cm radius of bending to 2 cm radius of bending. The stiffener 146 may be porous to permit a solution to access the sling 150 during a soak with a solution. Examples of such materials include, but are not limited to, polyethylene and polyethylene terephthalate made porous by methods well known in the art. Other suitable materials will be apparent to those skilled in the art. The dilator 140 and the stiffener 146 may be adapted to releasably engage the sling 150 . The dilator 140 may also be marked to indicate the position of the sling 150 in the body. The marking(s) 148 are placed along at least a portion of the length of the dilator 140 . In this manner, as the surgical device 110 is passed through the body, the user can determine the location of the sling 150 in the body by referring to the markings 148 on the dilator 140 . Referring to FIG. 4 , the sling 250 can be made of any biologically acceptable material for implantation into a body. The material can be a supple material that is sterile, or can be effectively sterilized, and is otherwise biologically acceptable for implantation into a body. For example, the material can be a synthetic polymer, a processed animal tissue, or a combination of synthetic polymers and animal tissue. The term “processed animal tissue” means tissue from an animal source, wherein antigenic sites within the tissue are bound, destroyed, or removed so as to reduce the antigenicity of the tissue. Slings are also described in U.S. Pat. No. 6,042,534 issued Mar. 28, 2000, the entire disclosure of which is incorporated herein by reference. Where the material is processed animal tissue, the tissue can include, among others, porcine tissue, bovine tissue, ovine tissue, equine tissue, and human tissue. Human tissue can be obtained from human cadavers or living donors. Processed animal tissue can be made from tendons, ligaments, and fibro-serous tissues. Where the processed animal tissue is made from fibro-serous tissues, the tissue can be from the dura mater, pericardium, peritoneum, tunica vaginalis, and dermas. Typically, these tissues are cleansed, dehydrated, cross-linked, and sterilized. Processed animal tissues are preferably chemically cross-linked animal tissues prepared by any of a number of methods that are well known in the art. However, any method of reducing or removing the antigenic sites within the tissue can be used to prepare the animal tissue. Examples of such methods include, but are not limited to, freeze-drying, protease treating, and acid treating the tissue to remove the antigenic sites. Tissues from a patient's own body will not need to undergo these processing steps. Synthetic polymers include polymers such as polytetrafluoroethylene (PTFE), such as Teflon® (DuPont, Wilmington, Del.); expanded polytetrafluoroethylene (EPTFE), such as Gore-Tex® (W.L. Gore & Associates, Inc., Newark, Del.), polyesters or polyethylene terephthalates, such as Dacron® polyester (DuPont, Wilmington, Del.), and silicone elastomers. Other suitable materials will be apparent to those skilled in the art. Combinations of synthetic polymers and processed animal tissues can also be used in slings 50 , 150 , 250 of the present invention. These combinations may include spliced strips having a combination of parts, including parts made of synthetic polymers and of processed animal tissues. Such combinations preferably include animal tissue that is treated so as to cross-link the collagen or otherwise render impotent the commonly antigenic fibers in the animal tissue. An example of such a combination material is collagen-coated ultrafine polyester mesh (CUFP) of the type disclosed by T. Okoski et al., ASAIO Trans., 1989, p. 391. The sling 250 , as shown in FIG. 4 , includes an elongated strip of material having variable dimensions, including a thickness, a width 256 and a length 257 . The dimensions of the sling 250 can be varied depending on the use of the sling 250 . In some embodiments, the length 257 can be greater than the width 256 . In other embodiments, the length 257 can be substantially the same or smaller than the width 256 . It is desirable for the width 256 to be at least sufficient to comfortably coapt the urethra to the vaginal wall. In one embodiment, the width 256 may be greater than about 0.5 cm, but less than about 4 cm. Other widths include, but are not limited to, 1–3 cm, 1.5–2.5 cm, and 2 cm. The length 257 should be sufficient to encompass at least a portion of the urethra and provide the urethra with sufficient pressure for proper coaptation. Proper coaptation may be accomplished with a length sufficient to encompass the urethra from at least 90° to about 180° of the circumference of the urethra. Alternatively, the sling 350 , as shown in FIG. 5 , may be made sufficiently long to be used to secure the sling 350 to the interior vaginal wall without the use of additional sutures. The sling 350 can include a first portion 351 , a middle portion 352 , and a second portion 353 . In this embodiment, the first portion 351 and the second portion 353 can be used as tethers. The middle portion 352 is that area of the sling 350 that is disposed adjacent the urethra. The first portion 351 and second portion 353 can also be used to secure the sling 350 in place. The width of the sling 350 may be the same for the first portion 351 , middle portion 352 , and second portion 353 . However, the width may be different for one or all three portions 351 , 352 , 353 . In FIG. 5 , the width of the middle portion 352 is greater than the first portion 351 or second portion 353 . The sling 350 may be a single piece or be made of a plurality of pieces that are joined by any of a number of well known attachment methods, such as securing the attached piece or pieces to the other portions of the sling 350 using sutures 354 as shown in FIG. 5 . Other methods include, but are not limited to, gluing, bonding, and heat sealing. FIG. 6 depicts another embodiment of the surgical device 410 . This embodiment includes a pouch 470 . The pouch 470 can be used to permit the sling 450 to be handled without damage, maintain a barrier preventing microorganisms from contacting the sling 450 , provide handling flexibility, and ensure that the sling 450 is introduced into the opening or pocket in the patient's body in the desired orientation. When the pouch 470 is made of a low friction material, the pouch 470 may also increase the ease of passage of the sling 450 through the opening created by the dilator 440 . The pouch 470 may be made of a variety of materials. Examples of such materials include, but are not limited to, polyvinyls and polyesters such as, polyethylene terephthalate (PET), polyethylene (PE), and ethylene vinyl acetate (EVA). Pouches are also described in copending U.S. patent application Ser. No. 09/023,965 filed Feb. 13, 1998, the entire disclosure of which is incorporated herein by reference. The pouch 470 can be flat to facilitate delivery of the sling 450 in a flat orientation. However, the pouch 470 may also be conical, or rolled conical, and be provided with means for flattening the sling 450 after delivery. Alternatively, the pouch 470 may be used in conjunction with a sling 450 made from a material that adopts a flat configuration after being delivered into the body. The pouch 470 can be clear or translucent to permit visualization of the sling 450 within. The pouch 470 can also be made of a porous material such as polyethylene, polyethylene terephthalate, or vinyl made porous by methods well known in the art. Other suitable materials will be apparent to those skilled in the art. The pouch 470 can be adapted to receive a dilator 440 and a sling 450 . The surgical device 410 may also include a stiffener 446 as shown in any one of FIGS. 7A–C . FIGS. 7A–C depict three variations of transverse cross-sections of the surgical device 410 along section 7 A, 7 B, 7 C – 7 A, 7 B, 7 C of FIG. 6 . The stiffener 446 and sling 450 may be housed in the pouch 470 ( FIG. 7A ). The sling 450 may be housed in the stiffener 446 that is housed in the pouch 470 ( FIG. 7B ). The sling 450 may be housed in the pouch 470 ; however, the stiffener 446 is adjacent but not housed in the pouch 470 ( FIG. 7C ). The length of the pouch 470 may be varied depending upon the length of the sling 450 . Alternatively, the pouch 470 may be greater or lesser in length than the sling 450 . The pouch 470 is adapted to releasably engage the sling 450 . It is desirable that the sling introduced into the opening in the patient's body be sterile. In this regard, FIG. 8 depicts a further embodiment of the surgical device 510 , in which the pouch 570 has pores 572 that can permit rehydration of a sling 550 and/or antibiotic or saline soaks of the sling 550 in the pouch 570 prior to introducing the sling 550 into the patient. The pores 572 may be of any size sufficient to permit wetting of the sling 550 . The pores 572 may range in size from about 100 microns to about 0.25 inches. Preferably, the pore size ranges from about 0.01 inches to about 0.15 inches. In one preferred embodiment, the pouch 570 is made of vinyl having a pore size of about 0.125 inches. In another aspect, the invention provides methods for introducing a sling from the vaginal cavity to coapt the urethra to the vaginal wall. One method described below includes the use of a surgical device, as contemplated in the present invention, to coapt the urethra 104 , as shown in FIG. 11 . While the procedure is described with particular reference to the surgical device 410 of FIG. 6 , those skilled in the art will appreciate that any of the surgical devices contemplated herein may be used in this procedure. In one method according to the present invention, a curved needle 420 such as a Mayo needle is advanced from the vaginal cavity 102 , through the anterior portion 108 of the vaginal wall, to pass to one side of the urethra 104 . The needle 420 is advanced around the urethra 104 to the other side of the urethra 104 until the needle 420 emerges from the anterior portion of the vaginal wall 108 back into the vaginal cavity 102 . Attached to the needle 420 is a dilator 440 that enlarges the puncture site created by the needle 420 . The dilator 440 can increase the area of the puncture site until the opening is sufficiently large to accommodate the sling 450 . The dilator 440 is passed about the urethra 104 until it emerges through the anterior vaginal wall 108 . The dilator 440 may contain markings 448 along its length to inform the user of the position of the sling 450 in the body. The length of the dilator 440 can permit grasping with a forceps and/or enable pushing the dilator 440 while maintaining tension on the first tether 430 to guide it about the urethra 104 . As the needle 420 and dilator 440 are passed through the body, the needle 420 and dilator 440 create a path along the longitudinal axis of the urethra to 104 for the sling 450 to follow. As the dilator 440 is withdrawn from the body into the vaginal cavity 102 , the appropriate marking(s) 448 can be used to alert the user to secure the second tether 460 to the anterior portion of the vaginal wall 108 to prevent further passage of the sling 450 and maintain its position above the anterior portion of the urethra 104 . The dilator 440 is then withdrawn from the body along with the pouch 470 . The sling 450 is thereby disposed axially to the urethra 104 . The first tether 430 is used to secure the sling 450 with enough tension to pull the urethra 104 against the vaginal wall 108 to thereby provide proper coaptation to the urethra 104 . Alternatively, the needle 420 , the dilator 440 , and pouch 470 may be removed from the body without first securing the second tether 460 . In this method, the physician will see two incisions (one on either side of the urethra 104 ) on the vaginal wall 108 and each incision having a tether 430 , 460 emerging from the incision. When the tether 430 , 460 is a suture, the tether 430 , 460 can be attached to a Mayo needle and secured to the anterior portion of the vaginal wall 108 approximately centering the sling 450 over the urethra 104 . The Mayo needle can then be attached to the other tether 430 , 460 to repeat the process. A cystoscope can be placed within the urethra 104 to view the interior of the urethra 104 . Under visualization, the second suture 460 can be tightened to coapt the urethra 104 and then secured to the anterior portion of the vaginal wall 108 . A device other than sutures may secure the sling 450 . The securing device can include, but is not limited to, a fastener, a clip, a staple, or a clamp. The tethers 430 , 460 may also be fastened to each other to secure the sling 450 . In sutureless embodiments, the sling 450 may be attached directly to the anterior portion of the vaginal wall 108 by a securing device. In another method according to the invention, an opening or pocket around the urethra 104 is created to receive the sling 450 . This opening or pocket can be created prior to passing the surgical device 410 through the body. The opening or pocket may be created in a variety of ways. For example, the opening may be created by hydrodissection in which a bolus of saline or other sterile solution can be injected through the anterior portion of the vaginal wall 108 targeting the tissue that surrounds the urethra 104 . For this procedure, the opening or pocket to be created is made to the anterior portion of the urethra 104 . An advantage of hydrodissection is that the urethra 104 is separated from the surrounding tissue along tissue planes to create an opening or pocket to receive the sling 450 . Typically, in hydrodissection procedures the volume of saline injected into the tissue is too large to be readily absorbed and, therefore, the tissue must separate to accommodate the saline bolus. Preferably, the volume of saline introduced into the tissue is from about 4 cc to about 10 cc. More preferably, the volume of saline is from about 4 cc to about 5 cc. Multiple injections may be required to create an opening or pocket of sufficient size. In an alternative approach, the opening or pocket can be created by balloon dissection in which a non-inflated, expandable balloon is introduced into the tissue between the anterior portion of the urethra 104 and the surrounding tissue. When the balloon is expanded, the surrounding tissue is dilated or torn, generating an opening or pocket of sufficient size to receive the sling 450 . In yet another approach, the opening or pocket can be created by dissecting the tissue between the anterior portion of the urethra 104 and the surrounding tissue with blunt dissectors and/or sharp cutters to accommodate the sling 450 . Variations, modifications, and other implementations of what is described herein will occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention as claimed. Accordingly, the invention is to be defined not by the preceding illustrative description but instead by the spirit and scope of the following claims.

A surgical device for use in a minimally invasive procedure to treat urinary incontinence can include a dilator coupled to a curved needle at one end and a sling at the opposite end. Urinary incontinence can be treated minimally invasively. One treatment includes positioning the sling on an anterior portion of the urethra to provide proper coaptation to the urethra.

SUMMARY OF THE INVENTION This invention concerns the compound 3,4,5-tris(4-pyridinylthio)-2,6,-pyridinedicarbonitrile, hereinafter Compound, having the following formula ##STR1## The compound is prepared by reacting substantially three molar proportions of 4-alkali metal mercaptopyridine, advantageously pyridine-4-sodium thiolate, as such or prepared in situ, with substantially one molar proportion of 3,4,5-trihalo-2,6,-pyridinedicarbonitrile, wherein halo is chloro or bromo, in the presence of a lower alkanol as reaction medium, advantageously methanol. The reaction mixture is heated to reflux and cooled. The solvent is removed in vacuo to leave the solid gummy product. Mixing of the gum with acetone, filtering off the solid and drying the latter gives the product as a yellow to orange powder. The latter may be recrystallized from absolute ethanol to give small crystals, melting at 186°-189° C with decomposition. DESCRIPTION OF THE PREFERRED EMBODIMENTS The following additional description and example further describe the invention and the manner and process of making and using it to enable the art skilled to make and use the same and set forth the best mode contemplated by the inventor of carrying out the invention. The compound of this invention has antimicrobial utility. In a conventional in vitro agar Petri dish dilution test for determining activity against bacteria and fungi, the minimum inhibitory concentration (MIC) in parts per million (ppm) against the following organisms was found: ______________________________________MIC, ppm, of Compound of Example______________________________________S. aureus 100T. mentagrophytes 100B. subtilis 100A. terreus 100P. pullulans 100M. phlei 10Ceratocystis IPS 100Cephaloascus fragans 100Trichoderm. Sp. Madison P-42 100______________________________________ In accordance with the present invention, Compound can be employed for the control of many bacterial and fungal pests. In still further operations, Compound or compositions containing it as a toxic constituent can be included in and on plaster, ink, wallboard, textiles, paper, adhesives, soaps, synthetic detergents, cutting oils, polymeric materials, embalming fluids, oil paints and latex paints to prevent the attack of various fungal pests and the subsequent economic loss due to the degradation of such products by microorganisms. Also, Compound can be distributed in textiles or cellulosic materials to preserve and protect such products from the attack of the organisms of rot, mold and decay. The exact concentration of the toxicant to be employed in the treating compositions is not critical and may vary considerably provided the required dosage of the effective agent is supplied in the ink, adhesive, soap, cutting oil, polymeric material, paint, textile, paper, or growth medium. The concentration of toxicant in liquid compositions generally is from about 0.0001 to 50 percent by weight. Concentrations up to 95 percent by weight are oftentimes conveniently employed, particularly in concentrate compositions. In dusts, the concentrations of the toxicant can be from about 0.1 to 95 percent by weight. In compositions to be employed as concentrates, the toxicant can be present in a concentration of from 5 to 98 percent by weight. For use as a spray, it is often convenient to apply the Compound as a wettable powder. EXAMPLE 3,4,5-Tris(4-pyridinylthio)-2,6-pyridinedicarbonitrile In a 500 ml single-neck flask equipped with a magnetic stirrer and a reflux condenser fitted with a calcium chloride drying tube were placed 250 ml of methanol and 2.30 g (0.10 mol) of sodium metal. After all of the sodium had reacted, 11.11 g (0.10 mol) of 4-mercaptopyridine was added and the solution was allowed to stir for five minutes. To the resulting thiolate solution, 7.65 g (0.033 mol) of 3,4,5-trichloro-2,6-pyridinedicarbonitrile was added. The reaction mixture immediately became cloudy and orange in color. The reaction mixture was heated to reflux and then cooled. The methanol was removed in vacuo leaving a red-orange gum. Mixing of the gum with acetone, filtering off the solid and drying the latter afforded 6.89 g of the title compound as a yellow to orange powder, m.p. 186°-189° C (dec.). A 1.00 g sample was recrystallized from absolute ethanol to give a 0.25 g analytical sample as small, yellow-orange crystals, m.p. 186°-189° C (dec.). Anal. % Calcd. for C 22 H 12 N 6 S 3 : C, 57.87; H, 2.65; N, 18.41. Found: C, 57.64; H, 2.59; N, 18.22. The procedure of the example, substituting 3,4,5-tribromo-2,6-pyridinedicarbonitrile for the given 3,4,5-trichloro analog gives exactly similar results. Preparation of Starting Materials The trihalopyridinedicarbonitrile starting materials can be prepared by the method of U.S. Pat. No. 3,325,503 as to the polychloro compound. The tribromo analog is prepared from the trichloro compound by the method described in U.S. Pat. No. 3,732,234, Column 16, under "Preparation of Starting Materials". The 4-mercaptopyridine starting material is a commercial product, available inter alia from Aldrich Chemical Company, Inc.

3,4,5-Tris(4-pyridinylthio)-2,6-pyridinedicarbonitrile is prepared by reacting three molar proportions of 4-alkali metal mercaptopyridine with one molar proportion of 3,4,5-trihalo-2,6-pyridinedicarbonitrile. The product has antimicrobial utility.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a hybrid fuel assembly and system for supplying an industrial vehicle with at least one alternate fuel supply. Specifically, at least one hybrid fuel assembly is mounted and disposed laterally on a side of the vehicle and in fluid communication with the vehicle, such as to increase the operational time and/or effectiveness of the vehicle. 2. Description of the Related Art Mine haul trucks are off-highway, two axle, rigid dump trucks, specifically engineered for use in high production mining and heavy duty construction environments. As such, haul truck capacities typically range from 50 short tons (45 tons) to 400 short tons (363 tons). In addition, the largest and highest payload capacity of such mine haul trucks is referred to as “ultra class” trucks. This ultra class includes haul trucks having a payload capacity of at least 300 short tons or greater. Numerous manufacturers throughout the world produce such mammoth vehicles which are engineered for both performance and long operable life. Trucks of this type are developed specifically for high production duty wherein material is transported in large quantities in order to lower transportation costs on a cost-per-ton basis. Typically mine haul trucks are powered by either direct drive diesel or diesel electric power trains frequently including a multiple horse power turbo charged diesel engine. Due to the exceptional size and weight of such vehicles, they cannot be driven on public access roads, but are ideal for high production environments wherein massive quantities of material must be moved, handled, relocated, etc. on a continuous or regular basis. Accordingly, it is well recognized that distillate fuels, specifically diesel, are used as the primary fuel source for such vehicles. Attempts to maximize the operational efficiency, while maintaining reasonable safety standards, have previously involved modified throttle control facilities. These attempts serve to diminish adverse effects of control mechanisms which may be potentially harmful to the vehicle engine operation as well as being uneconomical. Typical adverse effects include increased fuel consumption and wear on operative components. Therefore, many diesel engines and the vehicles powered thereby are expected to accommodate various types of high capacity payloads and provide maximum power for relatively significant periods of operation. As a result, many diesel engines associated with heavy duty and off-road vehicles are commonly operated at maximum or near maximum capacity resulting in an attempted maximum power delivery from the vehicle engine and consequent high rates of diesel consumption. It is generally recognized that the provision of a substantially rich fuel mixture in the cylinders of a diesel engine is necessary for providing maximum power when required. Such continued high capacity operation of the vehicle engine results not only in wear on the engine components but also in high fuel consumption rates, lower operating efficiencies, more frequent oil changes and higher costs of operation. Accordingly, there is a long recognized need for a fuel control system specifically intended for use with high capacity, off-road vehicles including mine haul vehicles of the type generally described above that would allow the use of more efficient fueling methods using other commonly available fuel sources. Therefore, an improved fuel control system is proposed which is determinative of an effective and efficient operative fuel mixture comprised of a combination of gaseous and distillate fuels. More specifically, gaseous fuel can comprise natural gas or other appropriate gaseous type fuels, wherein distillate fuel would typically include diesel fuel. Additionally, improved fuel control systems may further include increased capacity to carry lubricating fluids such as hydraulic fluid for powering a hydraulic lift or truck bed on such vehicles. Such a preferred and proposed fuel control system should be capable of regulating the composition of the operative fuel mixture on which the vehicle engine currently operates to include 100% distillate fuel, when the vehicle's operating mode(s) clearly indicate that the combination of gaseous and distillate fuels is not advantageous. Further, such a proposed fuel control system could have an included auxiliary function to act as a general safety system serving to monitor critical engine fuel system and chassis parameters. As a result, control facilities associated with such a preferred fuel control system should allow for discrete, user defined control and safety set points for various engine, fuel system and chassis parameters with pre-alarm, alarm and fault modes. In addition, the operation of such a fuel control system would be facilitated by the inclusion of a preferred mounting assembly for the alternate fuel supply. As such, the included and preferred mounting assembly would be readily adaptive for use on different vehicles while facilitating the secure, safe and efficient distribution of the alternate fuel in the intended manner. SUMMARY OF THE INVENTION This invention is directed to a system and attendant assembly to support at least one alternate fuel supply on a vehicle, wherein the fuel supply may be used with an improved fuel control system. The fuel control system may comprise controls for powering the hydraulic lift bed of a vehicle and appropriate injections of hydraulic fluid and lubricating fluid. The fuel control system may also comprise technology that allows for the safe and efficient use of a gaseous fuel such as, but not limited to, liquid natural gas (LNG), in combination with a predetermined quantity of conventional distillate fuel, such as diesel fuel. As a result, the composition of an “operative fuel mixture” used to power a vehicle engine will, be dependent on the operating modes of the vehicle engine and operating characteristics of the engine during the operating modes, be either a predetermined combination of gaseous fuel and distillate fuel or substantially entirely distillate fuel, absent any contribution of gaseous fuel. In initially broad terms, one embodiment of the present invention is directed to a system having a first hybrid fuel assembly, a second hybrid fuel assembly, and a fuel interconnect disposed on an industrial vehicle. As such, the first hybrid fuel assembly is disposed along a first side of the vehicle, preferably at a position laterally adjacent between the two tires, such as to provide sufficient clearance to the two tires. Similarly, the second hybrid fuel assembly is disposed along a second side of the vehicle, in a position laterally adjacent between the two tires of the second side of the vehicle. The vehicle is preferably a heavy duty industrial vehicle, such as a mine haul dump truck comprising Komatsu models 830 and 930. The fuel interconnect may be disposed on the vehicle and in fluid communication between the first and second fuel assemblies, such as to allow the refilling of both fuel assemblies from a single side of the vehicle. At least one preferred embodiment of the present invention is directed to a hybrid fuel assembly that may be utilized in the system described above. Accordingly, the hybrid fuel assembly may comprise a mounting assembly, an auxiliary fuel tank, and a shield assembly. The shield assembly is cooperatively structured to operatively engage the mounting assembly in order to retain the auxiliary fuel tank therein. The mounting assembly comprises a primary fuel tank formed along a substantially hollow interior within the mounting assembly. The mounting assembly will also comprise a recessed portion or auxiliary fuel area dimensioned and structured to operatively retain the auxiliary fuel tank. In at least one embodiment, the primary fuel tank is structured to contain diesel fuel and the mounting assembly is operatively connected and in fluid communication with the vehicle and a powering engine thereof, in order to deliver the diesel fuel to effect the operation of the vehicle. In another embodiment, the primary fuel tank may be structured to contain hydraulic fluid, and the mounting assembly may be operatively connected and in fluid communication with the vehicle and a hydraulic bed lift, in order to deliver hydraulic of lubricating fluid to effect the operation of the lift bed. In embodiments where the primary tank is intended to contain hydraulic fluid, the primary fuel tank may be smaller relative in proportion to the auxiliary fuel tank, because generally a mine haul dump truck requires less hydraulic fluid relative to diesel and/or LNG fuel. The auxiliary fuel tank is structured to contain liquefied natural gas (LNG) fuel, and may comprise varying dimensions, inversely related to the size and dimension of the primary fuel tank. The auxiliary fuel area may comprise an auxiliary fuel platform that is designed to retain the auxiliary fuel tank, such that the auxiliary fuel tank may be bolted down or otherwise attached to the platform. Additional auxiliary fuel retainers may be utilized to provide additional stability in securing the auxiliary fuel tank. The mounting assembly of the hybrid fuel assembly will be cooperatively structured in order to operatively engage a mounting area of the industrial vehicle. As such, mounting assembly may comprise at least one bracket or mounting structure which may be used to secure the mounting assembly to a side of the industrial vehicle. Further, additional shock absorber bushings may be added to minimize movement and/or absorb a portion of the force of impact against a side of the industrial vehicle during transit. At least one fuel access port will be integrated within the mounting assembly. In at least one embodiment, a second mounting assembly may comprise a rear fuel access port, which may be in fluid communications with the fluid interconnect, in order enable the refueling of the mounting assembly from a first mounting assembly on another side of the vehicle. In a preferred embodiment, a first mounting assembly may comprise a front diesel access port, a LNG access port, as well as a hydraulic refill port for refilling the various fuels and/or fluids necessary for the operation of the vehicle. The primary fuel tank formed within the mounting assembly may further comprise at least one baffle. The baffle is formed along an interior of the primary fuel tank in order to partition the primary fuel tank into a plurality of primary fuel compartments. This provides the benefit of minimizing slosh dynamics, so unwanted aeration does not occur in the fuel during the transit of the vehicle at high speeds and/or on rugged terrain. A plurality of structural baffles may be formed along the interior of the primary fuel tank to further bolster the structural integrity of the primary fuel tank and hybrid fuel assembly. The baffles may be disposed in varying configurations to provide for additional weight stability of the hybrid fuel assembly. In at least one embodiment, the mounting assembly may further comprise an access ladder, which is sufficiently dimensioned and disposed to allow an operator to gain access to a bed hoist cylinder of the vehicle and/or a hydraulic truck bed lift of the vehicle. Additional access points or areas may be built into the mounting assembly, such as to allow access to a LNG vaporizer integrated on a lower exterior of the mounting assembly. These and other objects, features and advantages of the present invention will become clearer when the drawings as well as the detailed description are taken into consideration. BRIEF DESCRIPTION OF THE DRAWINGS For a fuller understanding of the nature of the present invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which: FIG. 1 is a top rear schematic view of a system for implementing at least one alternate fuel supply to facilitate the operation of an industrial vehicle, specifically, first and second hybrid fuel assemblies are mounted on the lateral portions of the vehicle and in fluid communication with a powering engine of the vehicle. FIG. 2 is a rear perspective view of a hybrid fuel assembly for providing at least one alternate fuel supply to an industrial vehicle, specifically the fuel assembly may comprise diesel and liquefied natural gas. FIG. 3 is a front perspective view in partial cutaway of the hybrid fuel assembly of FIG. 2 . FIG. 4 is rear perspective view in partial cutaway of the hybrid fuel assembly of FIG. 2 , illustrating the internals of the primary fuel tank. FIG. 5 is a perspective view in exploded form of another hybrid fuel assembly for providing at least one alternate fuel supply to an industrial vehicle, specifically the fuel assembly may comprise hydraulic fluid and liquefied natural gas. FIG. 6 is a front perspective view in partial cutaway of the hybrid fuel assembly of FIG. 5 . FIG. 7 is a rear perspective view in partial cutaway of the hybrid fuel assembly of FIG. 5 , illustrating the internals of the primary fuel tank. FIG. 8 is a detailed perspective view of a front lower portion of the hybrid fuel assembly of FIG. 5 , illustrating the fuel access ports. FIG. 9 is a detailed perspective view in partial cutaway and of a bottom portion of the hybrid fuel assembly of FIG. 5 , illustrating the integrated vaporizer and vaporizer access area. Like reference numerals refer to like parts throughout the several views of the drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT As illustrated by the accompanying drawings, the present invention is directed to an assembly and system for modifying an industrial vehicle to include at least one alternate fuel supply used to facilitate the operation of the vehicle. Drawing attention to FIG. 1 , a system 100 of the present invention may comprise a first hybrid fuel assembly 300 , a second hybrid fuel assembly 200 , and a fuel interconnect 101 disposed on an industrial vehicle 500 . Accordingly, the first hybrid fuel assembly 300 is disposed along an exterior of the vehicle 500 , preferably at a mounting area 103 which is laterally adjacent and between the two tires 501 and 502 on a first side of the vehicle 500 . Similarly, the second hybrid fuel assembly 200 , if any, may be disposed at a mounting area 102 which is laterally adjacent and between the two tires 501 ′ and 502 ′ on a second side of the vehicle 500 . Each of the first and second hybrid fuel assemblies 200 , 300 are sufficiently structured and disposed to provide the tires 501 , 502 , 501 ′, 502 ′ with sufficient clearance taking in account of tire rotation. The industrial vehicle 500 may comprise any type of heavy duty industrial vehicles such as mine haul vehicles, dump trucks, bull dozers, and other commercial vehicles known to those skilled in the art. In a preferred embodiment, the present invention is designed to operatively engage and operate on commercial dump trucks, including but not limited to Komatsu models 830E, 830E-AC, 930E, 930E-4, 930E-4SE, and other present and future variations of these models. In a preferred embodiment, the first fuel assembly 300 comprises a hydraulic and liquefied natural gas (LNG) hybrid assembly, while the second fuel assembly 200 comprises a diesel and LNG hybrid assembly. The hydraulic fluid may be used to facilitate the operation of a hydraulic truck bed lift of the vehicle 500 . The diesel fuel and LNG may be used for powering a drive train of the vehicle 500 . The fuel interconnect 101 may be in fluid communication between the first fuel assembly 300 and the second fuel assembly 200 , such as to allow the refilling of both assemblies and respective tank(s) thereof from a single side of the industrial vehicle 500 . In other embodiments, either the hybrid fuel assembly 200 or 300 may also be mounted singularly on a side of the vehicle, leaving the other side of the vehicle empty, and in such an embodiment a fluid interconnect 101 between the two assemblies may be omitted. Each of the first and second fuel assemblies 200 , 300 are described in greater detail below. As represented in FIGS. 2-4 , one illustrative embodiment of a hybrid fuel assembly 200 is shown to initially comprise a mounting assembly 201 , an auxiliary fuel tank 220 , and a shield assembly 202 . The shield assembly 202 is cooperative structured to operatively engage the mounting assembly 201 in order to retain the auxiliary fuel tank 220 therein, and to protect both the auxiliary fuel tank 220 and the mounting assembly 201 from the external environment. The shield assembly 202 may accordingly be thermal insulated and/or be formed of sufficiently rigid material(s). The mounting assembly 201 comprises a primary fuel tank 210 formed along a hollow interior within said mounting assembly 201 . The mounting assembly 201 further comprises an auxiliary fuel area 225 sufficiently dimensioned and structured to operatively retain the auxiliary fuel tank 220 . The mounting assembly 201 may be formed in the dimensions of a substantially trapezoidal prism with a hollow interior on a diagonal side structured to retain the auxiliary fuel tank 220 , such as at the auxiliary fuel area 225 . In at least one embodiment, the primary fuel tank 210 is structured to contain diesel fuel for powering an engine and/or drive train of the vehicle 500 , whereas the auxiliary fuel tank 220 is structured to contain LNG as an alternate fuel also for powering an engine and/or drive train of the vehicle 500 . The primary fuel tank 210 may comprise approximately 650 gallons of useable diesel fuel, but may also comprise diesel fuel amounts in the 500 to 700 gallon range, in various embodiments designed for the Komatsu 830 or 930 model dump trucks. The auxiliary fuel tank 220 containing LNG may then comprise of corresponding sizes, in order to accommodate for the relatively larger diesel fuel capacity, and so as to not overload the weight bearing capacity on a side of the vehicle 500 . For example, the larger the primary fuel tank 210 capacity, the smaller the auxiliary fuel tank 220 capacity. Auxiliary fuel area 225 may further comprise an auxiliary fuel platform 221 which is substantially flat and designed to retain the auxiliary fuel tank 220 , such that auxiliary fuel tank 220 may be bolted down onto the platform 221 . In order to provide additional stability to the attachment of the auxiliary fuel tank 220 , auxiliary fuel area 225 may further comprise additional auxiliary fuel retainers 222 shaped to conform to an exterior of the auxiliary fuel tank 220 . These auxiliary fuel retainers 222 may form arch-like structures that are in abutting and partially surrounding relations to the auxiliary fuel tank 220 , when the auxiliary fuel tank 220 is operatively disposed and engaged with the auxiliary fuel area 225 . In order to affix the hybrid fuel assembly 200 to the vehicle 500 , the mounting assembly 201 is cooperatively structured to operatively engage a mounting area of the industrial vehicle. The mounting area is preferably located at an area laterally adjacent between the two tires on a side of the vehicle, such as illustrated in FIG. 1 at mounting areas 102 or 103 . To facilitate the operative engagement of the mounting assembly 201 to a mounting area of the vehicle, the mounting assembly 201 may further comprise at least one bracket 215 for affixing or mounting the mounting assembly 201 to the industrial vehicle 500 . A plurality of bushings or shock absorber bushings 214 is preferably formed along a rear exterior of the mounting assembly 201 , such as to absorb and minimize the force of impact against a side of the industrial vehicle 500 , and/or to provide a cushion and minimize movement of the mounting assembly relative to the industrial vehicle 500 when the vehicle is operating at high speeds and/or on rough terrain. The shock absorber bushings 214 may be formed from a number of shock absorbing materials, such as polymers, visco-elastic polymers, visco polymers, rubber, neoprene, silicone, and the like. Mounting assembly 201 may additionally comprise a front fuel access port 211 , and may further comprise a rear fuel access port 211 ′. In embodiments where each of two hybrid fuel assemblies 200 are mounted on each of two sides of a vehicle, a user may utilize the rear fuel access port 211 ′ of one hybrid fuel assembly 200 , in fluid connection with a fuel interconnect to the other hybrid fuel assembly 200 , such that the user may refuel both hybrid fuel assemblies 200 from on a single side of the vehicle. The fuel access ports 211 , 211 ′ may be in fluid communication with the primary fuel tank 210 in at least one embodiment, but may also be in communication with the auxiliary tank 220 in other embodiments. Additional and separate fuel access ports may be used for the auxiliary tank 220 in yet other embodiments. Mounting assembly 201 is also structured and disposed to facilitate the operative communication of its primary fuel tank 210 and auxiliary fuel tank 220 with a powering engine, drivetrain, and/or other mechanical or electrical operations of the vehicle. Drawing attention to FIG. 4 , a partially rear cut away view further illustrates the details of the primary fuel tank 210 formed along an interior of the mounting assembly 201 . Accordingly, and in a preferred embodiment, the primary fuel tank 210 comprises at least one baffle 212 formed along an interior of the primary fuel tank 210 . The baffle 212 is structured and disposed to partition the primary fuel tank 210 into a plurality of primary fuel compartments 213 . In preferred embodiments, a plurality of structural baffles 212 are formed along an interior of the primary fuel tank 210 to bolster the structural integrity of the mounting assembly 201 . This is particularly advantageous due to the substantially hollow interior of the mounting assembly 201 used for storage of a fuel. The resulting smaller primary fuel compartments 213 is also advantageous because it reduces the slosh dynamics of the liquid fuel, and thus results in a higher efficiency of operation for the vehicle. Further, reduced slosh dynamics also decreases the amount of entrained air or cavitation in diesel fuel, which may otherwise cause retarded injection timing and thus negatively affect diesel engine performance. In at least one embodiment, the primary fuel tank 210 additionally comprises at least one primary fuel compartment 213 ′ disposed in underlying relations relative to the auxiliary fuel platform 221 . The existence of the lower fuel compartment 213 ′ provides further weight stability to the hybrid fuel assembly 200 , and reduces potential movement of the assembly 200 relative to the vehicle 500 , which offers another added advantage particularly when the vehicle 500 is functioning on uneven and off-road terrain. As represented in FIGS. 5-9 , another illustrative embodiment of a hybrid fuel assembly 300 is shown, also for mounting on a side of the vehicle 500 . Similarly, this embodiment initially comprises a mounting assembly 301 , an auxiliary fuel tank 320 , and a shield assembly 302 , which may comprise a two piece construction as illustrated in FIG. 5 . Similar to the above embodiment, the shield assembly 302 is cooperative structured to operatively engage the mounting assembly 301 in order to retain the auxiliary fuel tank 320 therein, and to protect both the auxiliary fuel tank 320 and the mounting assembly 301 from the external environment. The shield assembly 302 may accordingly be thermal insulated and/or be formed of sufficiently rigid material(s). The auxiliary fuel tank 320 is similar to the hybrid fuel assembly 200 above, but may comprise differential sizes, shapes, and/or dimensions. The mounting assembly 301 also comprises a primary fuel tank 310 formed along a hollow interior within the mounting assembly 301 , and may share certain characteristics and components of the mounting assembly 201 above. The mounting assembly 201 may similarly be formed in the dimensions of a substantially trapezoidal prism, having a hollow interior along a diagonal side structured to retain the auxiliary fuel tank 320 , such as at the auxiliary fuel area 325 . The hybrid fuel assembly 300 further comprises a LNG vaporizer 330 , as well as additional components on the mounting assembly 301 that will be discussed in greater detail below. In a preferred embodiment, the primary fuel tank 310 is structured to contain hydraulic fluid for powering a hydraulic truck bed lift of the vehicle 500 , whereas the auxiliary fuel tank 320 is structured to contain LNG as an alternate fuel for powering an engine and/or drive train of the vehicle 500 . The primary fuel tank 310 may comprise approximately 246 gallons of hydraulic fluid, while the auxiliary fuel tank 320 may comprise approximately 300 gallons of LNG. Other preferred ranges may comprise 200-300 gallons of hydraulic fluid in the primary fuel tank 310 , and 250-350 gallons of LNG in the auxiliary fuel tank 320 . Fewer amounts of hydraulic fluid relative to LNG may be used depending on the utilization of the truck's hydraulic truck bed lift versus the range of travel of the vehicle 500 . The auxiliary fuel area 325 may similarly comprise an auxiliary fuel platform 321 as well as auxiliary fuel retainers 322 . The auxiliary fuel platform 321 is substantially flat and structured to retain the auxiliary fuel tank 320 , such that the auxiliary fuel tank 320 may be bolted down or otherwise affixed to the platform 321 . Auxiliary fuel retainers 322 may further be used to provide added stability to the auxiliary fuel area 325 , the retainers 322 may be shaped to at least partially conform to an exterior of the auxiliary fuel tank 320 . The retainers 322 may, as illustrated in FIG. 5 , form partially arching structures that are in abutting and partially surrounding relations to the auxiliary fuel tank 320 when the auxiliary fuel tank 320 is disposed in an operative engagement with the auxiliary fuel area 325 . The mounting assembly 301 may also comprise similar structural components for facilitating the mounting of the hybrid fuel assembly 300 to the vehicle 500 . Preferably, the hybrid assembly will also be mounted at an area laterally adjacent between the two tires on a side of the vehicle, such as at areas 102 or 103 in accordance with FIG. 1 . To facilitate the operative engagement of the mounting assembly 301 with the industrial vehicle 500 , similar mounting brackets, not shown, may be utilized. However, in a preferred embodiment and design for the Komatsu dump truck vehicles models 830 and 930, the present hybrid fuel assembly 300 is intended to replace and improve upon an existing manufacturer hydraulic tank. Accordingly, the mounting assembly 301 may comprise mounting structures 341 on each side of the mounting assembly 301 . These mounting structures 341 are structured to be backwards compatible with an existing mount area on the vehicle 500 . Mounting assembly 301 may similarly comprise a plurality of bushings or shock absorber bushings 314 using like materials described above, so as to minimize movement and/or absorb the force of impact against a side of the industrial vehicle 500 during transit in rugged terrain. Mounting assembly 301 preferably comprises separate fuel access ports for refilling the various fuels or alternate fuels used for operation of the vehicle 500 . In the preferred embodiment of hybrid fuel assembly 300 , the mounting assembly 301 may comprise a LNG access port 315 , a diesel access port 316 , and a hydraulic refill port 350 . The diesel access port 316 is intended to interconnect with a primary tank of another mounting assembly, such as the primary tank 210 of mounting assembly 201 recited in the previous embodiment above, via the fuel interconnect 101 . The LNG access port 315 may comprise a fuel connection or interconnect that is connected to and in fluid communication with the auxiliary tank 320 . In at least one embodiment, the LNG access port 315 may further be connected to and in fluid communication with the auxiliary tank 220 of the separate fuel assembly 200 . The hydraulic refill port 350 is connected to and in fluid communication with the primary tank 310 of the mounting assembly 301 . Each of the above fuel access ports or refill ports may further comprise additional components to facilitate the expedient refill of the respective fuels or fluids. For example, a fuel access port may further comprise a one-way check valve to prevent backflow and/or spillage during refill operations. As illustrated in FIG. 7 , the primary fuel tank 310 formed along the interior of the mounting assembly 301 may also similarly comprise at least one baffle 312 . The baffle 312 is formed along an interior of the primary fuel tank 310 and is structured and disposed to partition the primary fuel tank into a plurality of primary fuel compartments 313 . Two or more structural baffles 312 may be formed within the primary fuel tank 310 and be of sufficient form, material, and dimension to increase the structural integrity of the overall primary fuel compartment 313 and hybrid fuel assembly 300 . The structural baffles 312 may be formed, such that a first baffle 312 is in juxtaposing disposition and perpendicularly disposed relative to a second baffle 312 , which results in at least three primary fuel compartments 313 as shown in FIG. 7 . Additional horizontal baffles 312 ′ may be formed to further increase the number of primary fuel compartments 313 and/or the overall structural integrity of the primary fuel tank 310 . Fewer or greater structural baffles 312 may be used depending on the size and dimension of the mounting assembly 301 and corresponding primary fuel tank 310 . The resulting smaller primary fuel compartments 313 provides the added benefit of reducing slosh dynamics of the hydraulic fluid. Fluid aeration causes notable problems in hydraulic and lubrication oil systems, including unaccepted noise, poor component response due to the spongy behavior of aerated fluids, cavitation damage as well as severe fluid degradation. Accordingly, because a reduction in slosh dynamics reduces the entrained air in the fluids, these problems may be overcome. A lower fuel compartment may not be necessary in this embodiment, due to the smaller primary fuel tank size 310 and relatively larger auxiliary fuel tank 320 , which provides sufficient wait to stabilize the overall hybrid fuel assembly 300 during vehicle 500 function on even or off-road terrain. The mounting assembly 301 may further comprise an access ladder 232 . The access ladder 232 and mounting assembly 301 is sufficiently dimensioned and disposed such as to allow an operator to gain access to the access ladder 232 in order to access a bed hoist cylinder on the vehicle 500 having a hydraulic truck bed lift. This allows an operator to properly access and maintain a hydraulic truck bed lift of a vehicle 500 . Drawing attention to FIGS. 8-9 , additional access areas are provided for the convenience access of the LNG vaporizer 330 . A front vaporizer access 317 and/or a bottom vaporizer access 318 may be provided to facilitate the connection and maintenance of the LNG vaporizer 330 to the mounting assembly 301 and the auxiliary fuel tank 320 which comprises the LNG. In some embodiments, access area 317 may comprise a display panel integrated with electronic sensor(s) for displaying the current status of the hybrid fuel assembly 300 , and may comprise fuel status, fill level, maintenance schedule, error codes, etc. The LNG vaporizer 330 is structured and configured to convert the LNG into a gas for use by a powering engine of the vehicle 500 . Since many modifications, variations and changes in detail can be made to the described preferred embodiment of the invention, it is intended that all matters in the foregoing description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents. Now that the invention has been described,

A system and attendant assembly for incorporating at least one alternate fuel supply, such as of the type used in combination with a conventional distillate fuel, to power a heavy duty industrial vehicle, such as a mine haul dump truck. The system and attendant assembly includes a mounting assembly structured for containment and support of a primary fuel tank and an auxiliary fuel tank. The mounting assembly is disposed on a mounting area laterally adjacent between the two tires on a side of the truck, wherein the mounting assembly and mounting area are cooperatively disposed and structured to facilitate storage of the alternate fuel and operative communication and distribution thereof with the powering operations of the vehicle.

FIELD OF THE INVENTION The invention relates to condition monitoring of pumps and pump systems, and particularly, but not exclusively to condition monitoring of dry pumps. BACKGROUND OF THE INVENTION It is known to monitor dry pump condition by observing surges in motor torque or current. This is not, however, an ideal method of predicting pump failure. A pump will usually operate without any noticeable problem while deposits gradually build-up in the running clearances. This build-up usually takes place over a long period of time and eventually there will be contact, or rubbing, between two parts. When this happens, the heat generated causes thermal expansion, thus increasing the rubbing and causing further thermal expansion, often leading to seizure and pump failure. This contact, or rubbing, can be detected as a surge in motor current. However, the time between detection of a current surge and pump failure can be short, and in the case of a dry pump there is usually insufficient time to take action following the detection of a current surge. Pump failure due to seizure is always undesirable, but is even more of a problem where the pump is being used in a manufacturing process and the pump failure leads to the loss of a batch of product. For example, if a vacuum pump fails during the production of semi conductors, typically the batch of parts affected has to be rejected, which can be very expensive. In order to avoid the problem, pumps can be stripped down and parts replaced or cleaned as part of a planned period maintenance system. However, this can result in unnecessary expense as to be safe, the pumps have to be serviced more frequently than is actually necessary. In addition to problems associated with deposits forming in pumps, the efficiency of a pump and the system in which it operates can be adversely affected by the build-up of process by-products in the pump exhaust, piping connected to the exhaust and/or the pump itself. Yet another problem with pumps that can lead to pump failure is undetected bearing wear. BRIEF SUMMARY OF THE INVENTION It is an object of the invention to at least in part alleviate one or more of these problems. The invention provides a method of monitoring the condition of a pump or a component of a system comprising a pump which component is not a component of the pump, the method comprising the steps of generating a predetermined test condition in said pump or system component and obtaining signals indicative of a condition of said pump or system during a period in which said test condition is present. The invention also includes apparatus comprising a pump, pump controller and at least one sensing device for sensing a pump operating parameter, said pump controller being able to control said pump so as to selectively generate a predetermined pump test condition and the or each said sensing device providing signals indicating values of said parameter when said test condition is generated. The invention also includes apparatus comprising a pump, a controller, an exhaust conduit extending from said pump, at least one sensing device for sensing a condition in said conduit, a connection associated with said pump and or conduit for connecting said pump and or conduit with a source of pressurised gas and valving for controlling flow of said gas into said pump and/or conduit, said controller being able to control said valving to selectively admit said gas into said pump and/or conduit so as to generate a predetermined test condition in said conduit and the or each said sensor providing signals indicative of said condition in the conduit when said test condition is generated. In order that the invention may be well understood, embodiments thereof, which are given by way of example only, will now be described with reference to the drawings, in which: BRIEF SUMMARY OF THE DRAWINGS FIG. 1 is a block diagram illustrating a pump system; and FIG. 2 is a flow diagram illustrating a sub-routine carried on a data carrier for use in implementing a pump monitoring method. DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 1 , a system is shown in which a pump 10 is connected to a pipe, or conduit, 12 running from a process chamber 14 . The process chamber could be one in which, for example, semi conductors are processed. An isolation valve 16 is typically provided in the conduit 12 between the pump and the process chamber. The pump exhaust 18 is connected to a conduit 20 leading to an abatement system 22 . An abatement system, as is well known to those skilled in the art, is a filtering or treatment system for cleaning the exhaust gases. The pump exhaust 18 and the conduit 20 define a passage for exhaust from the pump. The pump 10 comprises a stator and a rotor (not separately illustrated) and includes an electric motor 24 by which the rotor is driven. In the illustration, the motor is shown outside of the pump. However, it will be appreciated that this is for ease of illustration and, as is well known in the art, the motor may be disposed internally or externally of the pump casing and suitable gearing may be provided between the motor and the rotor. The pump has a controller 26 which will typically comprise a processor and some memory capacity. Typically, the controller will be an integral part of the pump, but it may instead be provided as a separate unit, or could be a PC that communicates with the pump via suitable interfaces. A sensor 30 is associated with the motor and is provided to detect motor torque or the current supplied to the motor. Any suitable sensor may be used. One example is a current clamp probe, which, as will be known to those skilled in the art, is a probe that can be clamped around a motor lead to perform non-contact current measurements, without interrupting the circuit under test. The pump may be connected with a source 34 of coolant that is pumped through the pump in order to cool the pump 10 . The source 34 may be mains pressure water, which is directed to a drain once it has passed through the pump. Another option is that the source 34 could be a part of a recirculating cooling system that includes a heat transfer device in which the coolant circulating through the pump is cooled by a heat transfer process. Suitable recirculating cooling systems will be well known to those skilled in the art and will not therefore be described in further detail herein. The system includes some means, typically valving such as an electrically controlled valve 35 , which allows the controller 26 to control the flow rate of the coolant to the pump. A pressure sensor 32 is provided in the exhaust conduit 20 . Any suitable sensor may be used. One example of a suitable sensor is a diaphragm connected with a strain gauge or gauges. In use, the pump would function in the usual way, continuously or intermittently drawing gases from the processing chamber during the processing of products therein. During periods in which the pump is not in use, and in some cases even when the pump is in use, diagnostic tests may be carried out in order to provide data for assessing the condition of the pump and/or the pump system. One such test is to determine the condition of the running clearances in the pump and the bearing condition. In this test, the controller 26 is switched to a test mode and runs the pump in such a way as to stress the pump. The pump can be stressed in various ways: 1) The pump can be run at its normal operating speed, the shaft speed then reduced for a predetermined period (say three minutes) followed by an increase above the normal operating speed for a predetermined period of time (say three minutes). The increase and decrease in speed could, for example, be 10% above and 10% below the normal operating speed. 2) Where the pump is fed with coolant from a source 34 , the coolant flow could be reduced to, for example, 25% of the usual flow rate for, for example, 10 to 20 minutes. At the end of the reduced flow period, the flow rate would be restored to its usual level or possibly increased to a higher level to cause a perturbation of pump temperature. 3) Changing the gas flow rates through the pump, by, for example, increasing the flow rate by as much as 10 to 100 times the rate of that when the pump is in a usual operating mode. The duration of this increased throughput could, for example, be between 10 seconds and one minute 4) A combination of two or more of methods 1) to 3). During a period in which the pump is under test, signals indicative of the current drawn by the motor 24 are provided by the sensor 30 and communicated to the controller 26 where they are stored in the memory. A program operated by the controller can then compare all or some of the data received from the sensor 30 during the test with pre-programmed data held in the memory and/or data received during previous tests. On the basis of this comparison, a prediction can be made of the remaining life of the pump before a defined pump condition should occur. If the result of the test is an indication that the pump may fail within a predetermined period, the pump should be replaced. In this connection, the controller 26 can be equipped in various ways to provide an indication of the result of the test. For example, the controller 26 could be linked to an audible device 36 that would provide an audible message indicating the need for pump replacement or that the pump is likely to fail within a specified period. In addition, or as an alternative, the controller 26 could be linked to a visual display device 38 . The visual display device could be a simple warning light or a screen on which an indication of the test result could be displayed. As a further option, the visual display device 38 could comprise a printer. If desired, if the test result indicates certain conditions of the pump, the controller 26 could be configured to render the system inoperable until such time as a manual override is operated or resetting takes place following servicing or replacement of the pump. Another test can be carried out to determine the condition of the pump exhaust 18 and/or exhaust conduit 20 . In this test, a high purge flow of gas, for example 100 standard litres minute, is injected into the pump 10 or the exhaust conduit 20 upstream of the area to be tested. It will be understood that the pressure sensor 32 will be positioned relative to the position or positions at which the gas is injected so as to provide signals suitable for determining the condition of the area to be tested and that it may be appropriate to provide a plurality of such sensors at spaced apart locations in order to provide the desired result. The injection period would be relatively short, for example, 10 seconds to 1 minute. In FIG. 1 , the gas is shown being injected into the conduit 20 at a position upstream of the pressure sensor 32 via a pipe 40 . Injection into the pump is indicated by a dashed line representing a pipe 42 . The purge gas will typically be nitrogen fed from a source of compressed nitrogen 44 but other gases and/or sources could be used instead. Valving 46 is provided in the pipe 40 by means of which the flow of the purge gas can be controlled. This valving will typically comprise a valve electrically controlled by the pump. In the case of injection into the pump itself, this test could be a part of method 2) of the stress test mentioned above and would be carried out when the pump is not in use. If the purge gas is injected into the exhaust, the test could be carried out when the pump is in use. During a period in which the pump is under test, signals indicative of the pressure in the conduit 20 are provided by the pressure sensor 32 and fed to the controller 26 where they are stored in the memory. The controller 26 compares all or some of the received pressure data with the input gas flow rate and pre-programmed data and/or the data produced by previous tests to determine the level of blockage and/or useful service life of the pump exhaust/exhaust conduit 12 . The above-described methods of providing an indication of the results of a stress test on the pump can be used to indicate the results of this test and similarly, the controller may be able to render the system inoperable if certain system conditions are indicated. It will be appreciated that the system may be equipped so as to permit the controller to carry out one or both of the above described tests as desired and that where only one of the tests is required, the appropriate one of the sensors 30 , 32 can be omitted from the arrangement shown in FIG. 1 . In the arrangement described above the tests are performed under the control of the controller 26 , which is equipped to analyse the test results and to provide an indication as to the outcome of the test. However, the pump need not stand-alone and the testing regime can be integrated into a central system, which allows the test data to be analysed in connection with test data from other pumps. For this purpose, the pump may be connected to a network indicated in FIG. 1 by box 50 . The connection to the network 50 may be via the controller 26 . However, the pump may be directly connected to the network allowing a central controller to control the pump without a local controller for the pump. The box 50 indicates a network system such as the FabWorks 16 or FabWorks 32 systems marketed by BOC Edwards. These systems permit the data collected from the sensors 30 , 32 to be transmitted to a central hub where the data can be compared with pre-programmed data, previous test data from the pump under test and/or test data from other pumps. The FabWorks system can be enabled to provide a secure internet connection so that the data analysis can be carried out at a central hub operated by, for example, the pump manufacturer. Alternatively, the FabWorks system can be enabled to work on an intranet operated by the pump user. It will be understood that network systems other than the Fabworks systems could be used. The tests should be performed relatively frequent to reduce the risk of the tests themselves causing the pump or pump system to fail. The controller 26 and/or central hub may be able to permit manual commands to initiate the performance of a test. However, to ensure reliable monitoring of the pump or pump system, it is preferred that additionally, or as an alternative, the tests are initiated automatically and for this purpose, the controller 26 or a computer of the central hub is preferably able to initiate the performance of a test at predetermined intervals. If the test is one that has to be performed when the pump is not in use, the controller 26 or computer is able to determine the use condition of the pump. If the result of the interrogation is that the pump is not able to be tested, the controller or computer will preferably be able to interrogate the pump again after further predetermined interval that is less, and preferably much less, than the usual predetermined interval between tests and this process may be repeated at intervals of decreasing length in the event the pump is still not in a condition to be tested. The above-described methods of providing an indication of the result of a stress test on the pump can also be used to provide an indication that it was not possible to conduct a scheduled test. Similarly, if it is determined that a test has not been conducted sufficiently recently, the controller or hub computer may be able to render the pump or pump system inoperable until some form of manual intervention has taken place. In an alternative control strategy, the controller or hub computer may be enabled to detect when the pump has assumed an idle condition, and having detected an idle condition, would then check in a memory to determine when a test was last carried out. If a predetermined interval had elapsed since the last test or tests, the controller or hub would cause a new test or tests to be initiated. Of course, tests could be initiated whenever an idle condition is detected, but this would not be a preferred strategy. One method of detecting the operating condition of the pump, that is whether the pump is idling or in use, would be to analyse the current drawn by the pump motor using signals from the sensor 30 , although other indicators could be used. It is preferred that the signals from the tests are used in an algorithm to produce an indication of the service life of the pump or pump system before a predetermined pump condition is likely to occur and in doing this, it is expected that the signals from the sensor during the most recent test will be compared with signals from previous tests, signals from the sensors of other pumps and/or pre-programmed data. However, in addition, or as an alternative, the signals from the most recent test may be analysed in isolation and a determination made on the indications from those signals. For example, if a threshold value is detected a determination may be made that servicing or replacement action should be taken. It is expected that such a regime would more likely be applied to the results of testing on the pump exhaust passage than on results of the pump stress test. It will be appreciated that it is most likely the testing procedures will be implemented by means of software loaded into the controller or a computer of the hub and that this, together with the fact that sensors such as a current clamp or pressure transducer, can be incorporated with relative ease, means that the monitoring method can readily be applied to existing pumps and systems. For example, the software for implementing the method may be provided on data carrying mediums such as a floppy disc or compact disc. Another option is for the software to be downloaded via the internet or an intranet. Yet another option is for the code to be incorporated in a chip which can be substituted for an existing chip in a controller by itself or more likely as part of a replacement card. It will be understood that software for implementing the monitoring system may take many forms and that many possible routines and algorithms could be developed. An example of a sub-routine held on a data or carrier 60 in the form of a floppy disc is shown in FIG. 2 . It will be seen that the sub-routine implements the pump stressing method 2) described above and provides for disabling of the pump in the event the pump condition is determined as not meeting an ‘OK’ condition. By way of an example, a determination that the ‘OK’ condition is not met could be based on the occurrence of two successive tests that indicate the pump is approaching a failure condition, although of course many other criteria could be used. It will be understood that the system and methods described above can be modified in many ways. For example, transducers may be provided for use in controlling the electrically controlled valving 35 , 46 to create a feedback loop by which the valving can be more precisely controlled. Examples of such transducers are temperature sensors for sensing the temperature of the pump or coolant after it has flowed from the pump, or flow sensors for sensing the coolant or purge gas flow or the gas flow in the conduit. It will be appreciated that the data collected during the tests may be used to provide an indication of other areas of the pump or system. For example, the signals obtained from the conduit 20 may be used to assess the amount of blockage in the conduit and also of parts of the pump as there should be a correlation between the two. It will also be appreciated that the control strategy may be such that signals from the sensors are sampled only at predetermined periods during testing of the pump or system to ensure that the signals are representative of a period in which the predetermined test condition has actually been achieved. Another option would be to disregard the obtained signals until such time as a predetermined threshold value is obtained.

A method of monitoring the condition of a pump ( 10 ) or at least one component of a system that includes a pump which component or components are not a part of the pump, includes the step of generating a predetermined test condition in the pump or system component or components. During a period in which such a test condition is present, signals indicative of the pump or system component or components are obtained. Wear in the pump bearings, the build-up of deposits in the pump or in pipework forming a part of the pump system can be detected or predicted and corrective action taken before the pump or system fails. By providing a method of monitoring pump or system condition in-situ, it is possible to reduce the likelihood of pump failure in use and the need to carry out over frequent servicing of the pump.

BACKGROUND OF THE INVENTION [0001] The present invention relates to the actuation and de-actuation of cylinders of an internal combustion engine by deactivation and activation of the gas-changing valve of the respective cylinder. [0002] U.S. Pat. No. 5,787,855 discloses a switching off of cylinder groups of an internal combustion engine by deactivation of the gas-changing valve. With motors with many cylinders, a driving situation exists in which the required power can be provided from a part of the cylinder. The switching off of one or more cylinders leads to the situation that the remaining operating cylinders are operated with an increased power and better efficiency. EP 37269 likewise shows a switching off of gas-changing valves. A continuous production of the valve stroke is known from DE 195 01 386. [0003] The deactivation and activation of cylinders should be as undetectable as possible for the driver. In particular, no irregular moment of rotation change should occur upon changing between complete engine operation in which all cylinders operate and partial engine operation, in which at least one cylinder is switched off. SUMMARY OF THE INVENTION [0004] The present invention is based on the problem of realizing the most simple, undetectable switching on and off of cylinders as possible for the driver. [0005] According to the present invention, the change between full engine operation and partial engine operation of a multi-cylinder internal combustion engine, in which at least the intake valve or the escape valve of a cylinder or a group of cylinders in full engine operation are activated and in partial engine operation, are deactivated. In a first step, a throttling of the power of the cylinder to be deactivated takes place and simultaneously, an increased of the power of the other cylinders takes place, so that the total moment provided from the engine follows a provided desired engine moment. In a second step, a switching off of the throttled cylinder takes place via the actuatable intake or escape valve of this cylinder. [0006] For reactivation of the switched-off cylinder, that is, for changing from partial engine operation to full engine operation, a switching-on of the throttled cylinder takes place in a first step via the actuatable intake or escape valve and in a second step, an unthrottling of the power of the cylinder to be reactivate takes place, along with a simultaneous reduction of the power of the other cylinders, so that the total moment provided from the engine follows a provided ideal engine moment. [0007] With the above-described process, the advantage is provided that the change between partial and full engine operation does not occur through a sudden, abrupt and detectable actuation. In addition, the shift of the moment of rotation preparation from all cylinders on a part of the cylinder is at least approximately uniform and substantially temporal. [0008] In this manner, particular advantages with variable valve controls with high temporal tolerances in switching-off operation is provided, which will be described below. [0009] The change between partial and full engine operation and from full-to partial engine operation is accomplished through a control command. Between the time point of the change by means of the control command and the time point to which the changing is effective, a known time interval elapses, which is dependent on the constructive qualities of the valve control. A high tolerance or measure of deviation of this time interval has the result that between the change of the rotational moment from the other cylinders and the effective change between both types of engine operation, a time difference can occur, so that the changing over is detectable in an unwanted manner by the driver. Systems, for example, in which a variable valve stroke is determined by means of the relative positions of an opening cam shaft and a closing cam shaft, which are connected by means of a mechanical coupling gear, can have such temporal tolerances. A system with opening and closing cam shafts is described in the previously noted DE 195 01 386. The temporal range and uniformity of the shift between the cylinders provides, therefore, that also with temporal differences between the reduction of the moment of rotation of the cylinder to be switched off and the increase of the moment of rotation of the cylinders to be further operated, the entire moment of rotation change of a cylinder group is never suddenly operative. [0010] One form of the invention contemplates that an internal combustion engine includes a respective throttle valve or flap for the cylinder to be switched off as well as the cylinders to be further operated, or an individual throttle valve. In this embodiment example, the throttle of the power of the cylinder to be deactivated takes place via a closing of the associated first throttle device and the increase of the power of the cylinders to be further operated takes place via an opening of the throttle device of the associated cylinders to be further operated. [0011] To re-actuate the switched-off cylinder, an un-throttling of the cylinder to be reactivated takes place by means of an opening of the first throttle device and a reduction of the power of the remaining cylinders via a reduced opening of the throttle device of the remaining cylinders. [0012] This provides the advantage that the invention can be used also with valve operations, whose opening stroke can be determined only digitally between zero and completely open. [0013] A further form of the invention relates to an internal combustion engine with uniform or at least finely-staged adjustable stroke of the intake valve. Here, the throttling of the power of the cylinder to be deactivated takes place via a reduction of the lift of its intake valve, and the increase of the power of the cylinder to be further operated takes place via an enlargement of the lift of its intake valve. [0014] For reactivating the deactivated cylinder, an un-throttling of this cylinder takes place via an increase of the stroke of the intake place to be reactivated and a reduction of the power of the remaining cylinders takes place via a reduction of the stroke of the intake valve of the remaining cylinders. [0015] Therefore, a further, separate throttle device is insurable, as is required in the subject matter of the other embodiment described above. [0016] Further advantages are provided with engines with a control apparatus for switching off of the cylinders and the re-operating of the cylinders: these types of control apparatus are typically connected with a bus system. The information is exchanged via the bus system non-synchronously with the calculating program of the individual control apparatus, which runs synchronously with the movement of the crank shat of the engine. With a digital switching off of the cylinder groups, a time slowing of the digital increase of the power of the other cylinder groups can take place, which the driver detects as a jolt or jerk. [0017] With the invention, in contrast, a digital switching does not take place, rather, a uniform transition. Because of the uniformity of the transition, no jolt or jerk occurs, when a control apparatus begins this uniform transition somewhat earlier than the other control apparatus of the counter-running transition. [0018] In conclusion, the invention affects an optimization of the uniformity of the moment of rotation upon changing between full and partial engine operation with minimal demands on the constructive complication of the switching-off of the valve. [0019] The invention is directed also at an electronic control device for performing at least one of the above-described methods or one of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS [0020] [0020]FIG. 1 shows the technical environment of one embodiment of the present invention; [0021] [0021]FIG. 2 shows a gas-changing valve plate 2 . 1 as an essential component of the deactivatable gas-changing control 4 with a gas-changing valve 2 . 2 , an operating device 2 . 3 , and a valve spring 2 . 4 ; [0022] [0022]FIG. 3 shows a flow diagram as an example of an embodiment of the inventive method for changing between full engine operation and partial engine operation of a multi-cylinder combustion engine; [0023] [0023]FIG. 4 illustrates the development of the opening angle; and [0024] [0024]FIG. 5 shows how the valve lift curve of the remaining cylinders is increased such that again the entire moment of rotation provided by the engine is not changed upon transition from full engine operation into partial engine operation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0025] In FIG. 1, reference numeral 1 designates an internal combustion engine with a right roller beam 2 and a left roller beam 3 . The left roller beam connects activatable and deactivatable gas-changing valves via a gas-changing control 4 . The activation state of the gas-changing valves is determined from a control apparatus 5 . The control apparatus 5 further determines the opening angle alpha_ 6 of a throttle valve or flap 6 in a left vacuum pipe 7 . The right roller beam analogously connected via a gas-changing control 8 , which in the illustrated example is not deactivatable, and via a control apparatus 9 , which regulates the opening angle alpha_ 10 of the throttle flap, 10 in the right vacuum pipe. In the illustrated position of the throttle flap, the cylinders of the left roller beam 3 are deactivated. The throttle flap of the left roller beam therefore is closed, and the throttle flap of the right beam is opened, as in normal conditions. The control apparatus are connected via a bus system 11 in the illustrated example. [0026] Instead of these two control apparatus connected via a bus system, also a single control apparatus can regulated the activation state of the gas-changing valve and the degree of opening of the throttle flap. The control apparatus assume a further function, such as the processing of input signals via operating parameters of the internal combustion engine and the regulation of further quantities, in particular, of the fuel volume and the ignition. [0027] [0027]FIG. 2 shows a gas-changing valve plate 2 . 1 as an essential component of the deactivatable gas-changing control 4 with a gas-changing valve 2 . 2 , an operating device 2 . 3 , and a valve spring 2 . 4 . The numeral 2 . 6 represents a cylinder head with a gas channel 2 . 5 the connection of the gas channel to the combustion chamber 2 . 8 of a cylinder is opened or closed by the valve 2 . 2 . [0028] In the closed state, the sealing surface 2 . 9 of the valve plate 2 . 10 rests spring loaded on the valve seat 2 . 11 of the cylinder head 2 . 6 . The connection is opened by lifting up of the valve plate 2 . 11 at a valve stroke x by operating of the valve 2 . 2 against the spring force by means of the operating device 2 . 3 . [0029] The operating device, for example, can include an electrically controlled hydraulic or mechanism. It is essential in connection with the invention that the cylinder can be deactivated by means of an effect of the operating device by a deactivation of the gas-changing valve. [0030] [0030]FIG. 3 shows a flow diagram as an example of an embodiment of the inventive method for changing between full engine operation and partial engine operation of a multi-cylinder combustion engine. Block 3 . 1 represents a main program for engine control, in which injection times, ignition time points, and so on, are calculated and issued. Subsequently thereto, first the engine is operated in full engine operation with all cylinders. In the frame of the main program, the partial engine operation is initiated under predetermined conditions. These predetermined conditions, for example, can correspond with determined partial regions of the load number/rotational number spectrum. These partial regions show particularly that the supplied moment of rotation from the control apparatus in consideration of the driver's wishes already can be run from a partial volume of the cylinder. If a requirement for the partial engine operation exists in the control apparatus, the main program branches off to step 3 . 2 , which represents the start of the partial engine operation issuing from the full engine operation. Subsequently, in step 3 . 3 , first a reduction of the moment of rotation made ready from cylinder group 1 takes place, and a counter-running increase of the moment of rotation, or the power, from cylinder group 2 takes place. [0031] The cylinder group 1 designates here the group of the cylinders to be deactivated, and the cylinder group 2 represents here the group of the cylinders to be further operated. When the end value of the designed reduction, or increase, of the moment of rotation/power of the different cylinder groups are achieved from the actual values, the valves of the cylinder group 1 are deactivated. [0032] Subsequently, a further operation of the engine with a partial program for the partial engine operation takes place, represented by step 3 . 4 . If a demand for full engine operation exists in the control apparatus, for example, by means of the driver's wish for an increased moment of rotation, the program branches off to step 3 . 5 , which represents the start of the full engine operation. [0033] Subsequently, in step 3 . 6 , an activation of the gas-changing valve of the cylinder group 1 . 1 takes place (that is, the previously deactivated cylinder). An increase of the power of cylinder group 1 in step 3 . 7 and an opposite reduction of the power of cylinder group 2 are linked up. The manner of procedure of step 3 . 7 means that the moment existing before the wish for increased moment from cylinder group 2 is separated first again on the cylinder groups 1 and 2 , before, then, by means of an increase of the power/moment of rotation of both cylinder groups, the driver's wish for increased moment calculation is carried. [0034] Alternatively, also the power of the cylinder group 2 can be maintained in step 3 . 7 , and the power of the cylinder group 1 can be increased successively on the value of the power of cylinder group 2 . With this alternative, there is the advantage of a faster reaction to the driver's wish for increased moment. [0035] [0035]FIG. 4 illustrates the development of the opening angle from 2 , the throttle flap 6 s and 10 from FIG. 1 corresponding to power correcting elements in correlation with the activation state of the gas-changing valve of the cylinders to be deactivated upon transition from full engine operation to partial engine operation. [0036] In FIG. 4. 1 , the time period on the left corresponds from t0 of the full engine operation (VMB), in which both throttle flaps 6 , 10 have an opening angle alpha_ 0 . The time period right from t1 corresponds with the partial motor operation (TMB). The throttle flap 10 is opened at a greater angle alpha_ 10 in contrast to the angle alpha_ 0 ; the throttle flap 6 is opened or completely closed at a smaller angle alpha_ 6 . Between the time points t0 and t1, the transition from full engine operation into partial engine operation is completed, as far as the throttle flap positions are related, with the previously described closing of the throttle flap 6 and the opposite opening of the throttle flap 10 . The closing of throttle flap 6 corresponds in this embodiment to the reduction of the power of the cylinder group 1 from step 3 . 3 of the previously-described flow diagram, and the enlarging of the throttle flap angle alpha ( 10 ) corresponds to the increase of the power, or the moment of rotation, of cylinder group 2 , likewise in step 3 . 3 of the flow diagram. FIG. 4. 2 illustrates the activation state of the gas-changing valve of the cylinders to be deactivated in temporal correlation to the running of the throttle flap opening angle according to FIG. 4. 1 . [0037] At time point t0, the transition from full engine operation into partial engine operation with a control command is released. Correspondingly, the throttle flaps angles change in FIG. 4. 1 Based on the sluggishness of the gas-changing vale displacement or based on a programmed lag time, the gas-changing valves are deactivated the same by occurrence of the control command, that is, displaced from activation state 1 into activation state 0 . Rather, this occurs first at a later time point t1, specifically, when the previous reduction or increase of the power of the different cylinder groups is terminated. The embodiment described here relates to a device with two throttle flaps or valves and a gas-changing function, that can be switched binary over between the state 1 , corresponding to an activation of the gas-changing valve, and state 0 , corresponding to a deactivation of the gas-changing valve. [0038] When, in contrast, in another embodiment, the maximal valve stroke x can be varied constantly between the value 0 corresponding to a deactivation and a maximal value, other realization possibilities are offered by the present invention. Then, for example, with an internal combustion engine with two cylinder groups, of which one is deactivatable and with only one common throttle flap or valve for both cylinder groups, the power, or moment of rotation of the deactivatable cylinder is returned constantly via a constant reduction of the valve stroke, and simultaneously, the throttle flap for all cylinders can be opened oppositely so that the entire moment of rotation provided by the combustion engine is not changed upon transition from full engine operation into the partial engine operation. [0039] Likewise, the invention can be realized with a completely variable valve control, in which also the filling control of all cylinders is realized via the formation of the valve lift curve. In this case, the valve lift curves of the cylinders to be deactivated are reduced successively in height until they reach the value 0 . Oppositely, the valve lift curve of the remaining cylinders is increased such that again the entire moment of rotation provided by the engine is not changed upon transition from full engine operation into partial engine operation. This is shown in FIG. 5. The two curves designated with VMB correspond to the valve lift curves of the gas-changing valves of all cylinders in full engine operation. In this case, the valve lift curves are the same. In partial engine operation, the valve lift curve of a group of cylinders return to the value 0 and the valve lift curve of the other group of cylinders is increased parallel. In the illustrated example, this corresponds to the valve lift curves designated as TMB. [0040] It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above. [0041] While the invention has been illustrated and described herein as a method for changing between full engine operation and partial engine operation, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention. [0042] Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.

A method for changing between full engine operation and partial engine operation of a multi-cylinder combustion engine includes the step of activating at least the intake valve or the escape valve of a cylinder or a group of cylinders in full engine operation and deactivating the intake valve or escape valve or a cylinder or group of cylinders in partial engine operation. In a first step, a throttling of power of the cylinder to be deactivated takes place, and simultaneously, an increase of power of the other cylinders takes place, such that the entire moment produced by the engine follows a predetermined ideal engine moment. In a second step, a switching-off of the throttle cylinder takes place by means of the actuatable intake or escape valve. This method avoids undesired changes of the total moment of rotational produced by the engine. The invention is also directed at a device for performing the method.

This application is a continuation of application Ser. No. 692,745, filed Apr. 24, 1991, now abandoned. BACKGROUND OF THE INVENTION On account of its toxicity to fish, but above all on account of its contribution to the eutrophication of waters, ammonium is a substance which should be completely removed from wastewaters. Whereas there are numerous industrial processes for the removal of high concentrations of ammonium, the removal of ammonium in ppm concentrations can only be economically achieved by biological processes. This is done by two specialized groups of bacteria which derive their energy for the cell metabolism from the oxidation of ammonia to nitrite (ammonia oxidizers) and further to nitrate (nitrite oxidizers). The ammonia oxidizers use CO 2 as the sole carbon source while nitrite oxidizers use additional carbon sources. The nitrate formed can be reduced to nitrogen by a number of heterotrophic bacteria at low oxygen concentrations and can therefore be completely removed (see for example (1)). However, disadvantages attending the microbial elimination of nitrogen lie in the low growth rates of the nitrificants. CO 2 is the sole carbon source so that cell growth is minimal. In addition, many organic compounds, such as isothiocyanates, amines, phenols and nitrogen-containing heterocycles inhibit the growth of ammonia-oxidizing bacteria. As a result, the biological elimination of nitrogen in industrial effluent treatment plants is seriously reduced. Since nitrificants cannot be rapidly and quantitatively determined by microbiological culture methods, there have hitherto been no possibilities for recognizing changes in the quantity of nitrificants in wastewater populations and for achieving an optimal treatment capacity by corresponding control measures. SUMMARY OF THE INVENTION According to the invention, it has been possible to solve this problem through the construction of gene probes for these ammonia-oxidizing bacteria. Using these gene probes, nitrificants in complex biomasses, such as are present in wastewaters and soils, can be quantitatively determined from the concentration of nucleic acid. In the gene probe test, the gene probe and complementary target DNA from nitrificants are specifically duplexed (hybridized). The gene probe is produced either synthetically (up to 100 oligonucleotides) or biologically on the basis of the sequence described in the following and is provided with a label (radioactivity, dye, enzyme). Its addition to a sample material containing nitrificants, for example nucleic acid lysates from aeration sludge or soils, results in hybridization by the complementary sequences of gene probe and nitrificant DNA. This hybridization reaction can be carried out in solution or with nucleic acids fixed to carriers (nitrocellulose, nylon membranes, beads). The hybridized nucleic acid is quantitatively evaluated through the labeling of the gene probe and thus provides a direct measure of the nitrificant content of the biomass of the wastewater or soil. The present invention also extends to gene probes isolated by the same method and to modified variants of the gene probes described in the invention which have the features and properties essential for carrying out the invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic of the preparation of a nitrosomonas-specific gene probe. FIG. 2 is a restriction map of the 6 kb gene probe in the vector pSPT 19 in both orientations. FIG. 3 is a restriction map of the 1.7 kb gene probe SPN 366.1. DESCRIPTION OF THE PREFERRED EMBODIMENTS The main applications for the new gene probes are in the testing and monitoring of nitrificant concentrations in the biological elimination of nitrogen in waste water treatment plants. The detection limit for the detection of nitrificants with the new gene probes is in the range of 10 5 to 10 6 bacteria. The detection sensitivity can be distinctly improved by amplification methods, such as for example the PCR method (polymerase chain reaction). A detection limit of 10 to 100 bacteria can be achieved by amplification on the basis of the gene probe sequences described in the invention. The invention is illustrated by the following Examples. Genetically engineered isolation of nitrosomonas gene probes The genomic nucleic acid from the strain Nitrosomonas europaea ATCC 19718 was isolated by a preparative lysozyme/SDS nucleic acid isolation method. To construct gene probes, the genomic DNA was cleaved with the restriction enzyme BamHI into 1-15 kb large DNA fragments, linked to BamHI-linearized pBR322 plasmid vector by genetic engineering and transformed into competent E. coli cells AG1. Ampicillin-resistant clones were isolated the next day and recombinant clones containing DNA of nitrosomonas were identified through the sensitivity to tetracycline of bacteria transformed with the plasmid vector. The cloning experiments were carried out by the genetic method described by Maniatis (2). The plasmid DNA was isolated from the recombinant clones by an analytical nucleic acid isolation method and the size of the nitrosomonas DNA incorporated was determined by gel-electrophoretic separation. The exact size of clones containing incorporated nitrosomonas DNA in the 1-15 kb range was determined by cleavage of the plasmids with the restriction enzyme BamHI and by gel-electrophoretic separation of the linearized plasmids. Clones with the exact insert sizes of nitrosomonas DNA are listed in Table 1. By reversed-phase hybridization, it was possible to determine which of the isolated nitrosomonas gene probes had the broadest detection spectrum for nitrosomonas. To this end, the individual gene probes were subjected to gel-electrophoretic separation in agarose gel and the gene probe DNA was subsequently transferred from the gel to a nitrocellulose filter and fixed. The genomic nitrosomonas DNA was suitably labeled (P 32 -ATP, biotin, digoxigenin, enzyme) and used as a gene probe in Southern blotting with the gene probes fixed to a nitrocellulose filter. A 6 kb gene probe SPN 323.13 was identified and produced a very strong hybridization signal in the Southern blotting hybridization test. This gene probe was analyzed for its nitrosomonas specificity by a dot blotting hybridization test. The experiments showed that the gene probe SPN 323.13 is specific for nitrosomonas and has the broadest detection spectrum for nitrosomonas of all the gene probes tested. This gene probe was used for the further development of shorter gene probes and chemically synthesized oligonucleotide gene probes. Genetically engineered development of nitrosomonas gene probes Other shortened gene probes were constructed on the basis of the 6 kb gene probe SPN 323.13 (FIG. 1). The gene probe was first molecular-biologically characterized by cleavage with various restriction enzymes. The linear restriction map of the gene probe is shown in both orientations in FIG. 2. The 1.4 kb ClaI fragment, the 1.7 kb ClaI-HindIII fragment and the 2.5 kb SalI-BamHI fragment were subcloned into the vectors pBR 322 and pSK Bluescript (Stratagene). Recombinant clones containing the individual gene fragments were isolated and molecular-biologically characterized. After cleavage with the corresponding restriction enzymes and gel-electrophoretic separation, the individual gene fragments were isolated by electroelution. These gene probes were then labeled with the usual labeling substances (P 32 ATP, biotin, digoxigenin, enzymes) and their specificity was determined in the gene probe test. By virtue of its high specificity for nitrosomonas strains and its nevertheless very broad detection spectrum for nitrosomonas, the 1.7 kb gene probe SPN 366.1 was identified as particularly suitable for the detection of nitrosomonas. For further optimization and synthesis of oligonucleotide gene probes, this gene probe was first molecular-biologically characterized by cleavage with restriction enzymes. The linear restriction map of the b 1.7 kb gene probe SPN 366.1 is shown in FIG. 3. To shorten the 1.7 kb gene probe SPN 366.1, the 0.2 kb, 0.3 kb, 0.5 kb and 0.7 kb gene fragments formed by cleavage with the restriction enzymes HindIII, AccI, PstI and ClaI and ClaI were subcloned into the vector pSK Bluescript (Stratagene). The 0.2 kb, 0.3 kb, 0.5 kb and 0.7 kb gene probes were isolated from the corresponding constructs by electroelution after cleavage with restriction enzymes and gel-electrophoretic separation in agarose gel. The gene probes were labeled (P 32 ATP, biotin, digoxigenin-UTP, enzyme) by the random prime labeling method and subsequently tested for their specificity and sensitivity in the gene probe test. It was found that the gene probes SPN 391.7 (0.2 kb), SPN 397.1 (0.3 kb), SPN 391.3 (0.5 kb) and SPN 391.16 (0.7 kb) did not show any significant differences in regard to specificity and sensitivity of nitrosomonas detection and were all equally suitable for use as gene probes. The gene probe tests with the gene probes SPN 391.7, 397.1, 391.3 and 391.16 are shown by comparison with the 1.7 kb gene probe SPN 366.1 in Table 2. Sequencing of the gene probe SPN 366.1 The 1.7 kb gene probe was sequenced on the basis of the gene probe SPN 366.1 (1.7 kb) and the 0.2 kb, 0.3 kb, 0.5 kb and 0.7 kb gene probes. Sequencing was carried out by the Sanger dideoxy chain termination method (b 5). The nucleotide sequence of the 1.7 kb gene probe SPN 366.1 is shown in the attached sequence listing. Chemical synthesis of oligonucleotide gene probes Oligonucleotide gene probes were chemically synthesized on the basis of the existing sequence of the 1.7 kb gene probe SPN 366.1 by the amidite method of S. L. Beaucage and M. H. Caruthers (6) . By gene probe tests with various oligonucleotides from the region of the 1.7 kb gene sequence of the gene probe 366.1, it was found that 15 mer-100 mer oligonucleotide gene probes from any regions of the 1.7 kb gene probe can be used for the gene probe test. The following oligonucleotide gene probes proved to be particularly suitable in the gene probe test: bases 1-53, bases 1315-1365, and bases 1610-1663 of SEQ ID No. 1. Carrying out the gene probe test To determine the specificity and sensitivity of the gene probes, a gene probe test was carried out with digoxigenin DUTP labeled gene probes using the Boehringer/Mannheim digoxigenin test kit. Labeling the nitrosomonas gene probes The gene probes were labeled with digoxigenin-dUTP by the random prime method of Feinberg and Vogelstein (3). Before the random prime labeling, the gene probes were cut out from the corresponding recombinant plasmids with restriction enzymes. The linearized gene probes were separated from the linearized plasmid vector by gel electrophoresis in 0.8% agarose gel. The gene probe DNA was cut out from the agarose gel and the gene probe was isolated from the agarose block by electroelution. The gene probe DNA was then further purified by extraction with phenol and precipitation with ethanol. Before labeling with digoxigenin-dUTP, the gene probe DNA was denatured by heating for 10 mins. in a water bath to 100° C. and rapid cooling on ice/NaCl. For labeling, 1 μg denatured gene probe DNA, 2 μl hexanucleotide mixture and 2 μl dNTP labeling mixture were combined, made up to 19 μl with sterile twice-distilled water and 1 μKlenow enzyme was added. Labeling with digoxigenin-dUTP was carried out for 60 mins. at 37° C. The reaction was then stopped by addition of 2 μl EDTA solution 0.2 mol/l pH 8 and the labeled DNA was precipitated with 2.5 μl LiCl 4 mol/l and 75 μl precooled ethanol (-20° C.). After 30 mins. at -70° C., the DNA precipitate was centrifuged off at 12,000 g and washed with cold ethanol, 70%, dried in vacuo and dissolved in 50 μl tris-HCl 10 mmol/l, EDTA 1 mmol/l pH 8. Hybridization with nitrosomonas gene probes For the hybridization experiments, the nitrosomonas-DNA-containing nucleic acid extracts from the biomass of wastewaters or soils were first denatured into the DNA single strands by heating for 10 minutes to 100° C. and rapid cooling on ice/NaCl. Nitrocellulose membranes were pretreated by swelling in water and 20×SSC (NaCl 3 mol/l, Na citrate 0.3 mol/l pH=7) and dried. Nylon membranes were used without any pretreatment. The denatured nucleic acid extracts were applied to the nitrocellulose or nylon membranes using a Schleicher & Schell Minifold II filtration unit and then fixed by baking in vacuo for 1 h at 80° C. or by UV crosslinking for 5 mins. using a UV transilluminator (nylon membrane). The nylon/nitrocellulose filters were sealed in a plastic bag containing 20 ml hybridizing solution (5×SSC; blocking reagent 0.5%; N-lauroyl sarcosine, Na salt 0.1%; SDS 0.02%) and prehybridized for 1 hour at 68° C. The prehybridizing solution was then replaced by 2.5 ml hybridizing solution (same composition) containing freshly denatured gene probe DNA (100 ng). The hybridization batch was incubated for 2 hours at 68° C. The filters were then washed for 2×5 mins. at room temperature with 50 ml 2×SSC; SDS 0.1% and then again for 2×15 mins. at 68° C. with 0.1×SSC 0.1% SDS. The filters were directly used for the detection of the hybridized DNA or were stored in air-dried form for subsequent detection. Detection of the hybridized nitrosomonas DNA An immunological detection reaction was carried out for quantitative detection of the hybridized nitrosomonas DNA. An antibody conjugate with coupled alk. phosphatase was used which binds to the hybridized digoxigenin-labeled DNA. The color reaction was started at an alkaline pH by addition of the colorless 5-bromo-4-chloro-3-indolyl phosphate and nitroblue tetrazolium. The blue precipitate formed was quantitatively evaluated after 2-12 hours with a Shimadzu CS430 densitometer. The following buffers were used for the detection reaction Buffer 1: Tris/HCl 100 mmol/l; NaCl 150 mmol/l pH 7.5 Buffer 2: 0.5% solution of blocking reagent in buffer 1 Buffer 3: Tris/HCl 100 mmol/l; NaCl 100 mmol/l, MgCl 2 50 mmol/l pH 9.5 Buffer 4: Tris/HCl 10 mmol/l, EDTA 1 mmol/l pH 8 Dye solution (freshly prepared) 45 μl NBT and 35 μl X-phosphate were added to 10 ml buffer 3. The nitrocellulose/nylon filters were washed for 1 minute in buffer 1, incubated for 30 minutes with 100 ml buffer 2 and rewashed with buffer 1. The antibody conjugate was diluted in a ratio of 1:5,000 in buffer 1 and the filters were incubated for 30 minutes with approx. 20 ml of the dilute antibody conjugate solution. Unbound antibody conjugate was removed by 2×15 mins. washing with 100 ml buffer 1 and the filters were subsequently equilibrated for 2 mins. with 20 ml buffer 3. The filters were then incubated with 20 ml dye solution in darkness in a sealed plastic bag. The color intensity of the individual slot blots was determined by densitometry by comparison with a co-applied nitrosomonas DNA standard. Specificity of the gene probes The specificity of the gene probes was analyzed by the described gene probe test. The nucleic acid was extracted from characterized gram-negative and gram-positive bacteria, including bacteria which degrade aromatic halogen compounds, aromatic nitro compounds, aromatic amino compounds, alkyl sulfonic acids and aryl sulfonic acids, and various nitrosomonas isolates and a dot blot hybridization test was carried out with the described gene probes to determine which bacterial lysates produced a positive hybridization signal (Table 2). Through the experiments, it was found that the developed nitrosomonas gene probes hybridized specifically with all nitrosomonas lysates and did not produce any hybridization signals with other bacterial lysates. Use of nitrosomonas gene probes for detecting and quantifying nitrosomonas in waters/wastewaters For detecting and quantifying nitrosomonas strains in waters/wastewaters, the total nucleic acid was first isolated from the centrifuged water/wastewater samples. 150 μl 10.5M EDTA and 150 μl twice-dist. H 2 O and 3 μl SDS, 20%, were added to 50 mg moist biomass which was then incubated in a water bath for 60 seconds at 100° C. and, immediately afterwards, was placed in an ice/salt bath for 1 minute. 600 μl Tris-saturated phenol was then added for the first extraction with phenol, followed after mixing by centrifugation for 5 minutes at 5,000 G. The extraction with phenol was repeated with the upper aqueous DNA phase. Small amounts of phenol were removed by subsequent extraction with ether. The ether phase was removed, the DNA was precipitated with isopropanol and was then centrifuged off at 5,000 G in a tabletop centrifuge. The DNA pellet was washed with 70% ethanol. The DNA pellet was then taken up in 220 μl TE buffer and, as described with reference to the gene probe test procedure, was fixed to nitrocellulose or nylon membranes and then hybridized with the described gene probes. For quantifying, nitrosomonas DNA standard was applied in concentrations of 250 ng to 3.5 ng corresponding to cell numbers of 2.5×10 6 to 3.5×10 4 nitrosomonas cells. The positive hybridization reaction was evaluated on the basis of the color intensity of the 5-bromo-4-chloro-3-indolyl nitroblue tetrazolium complex in a Shimadzu CS930 densitometer. The concentration of the nitrosomonas-specific DNA respectively the nitrosomonas cell titer in the sample material was determined by comparison with the slot blots of the nitrosomonas DNA standard. The detection limit of the described detection method was 10 5 -10 6 nitrosomonas bacteria. Use of nitrosomonas gene probes for detecting and quantifying nitrosomonas strains in soils For detecting and quantifying nitrosomonas bacteria in soils, the nucleic acid of bacteria present in the soil was isolated by the method of Torsvik and Marmur (4). 100 ml TE buffer (Tris/HCl 10 mmol/l, EDTA 1 mmol/l pH 8) were added to 10 g soil, the sample was thoroughly mixed and the soil was subsequently separated from the bacterial extract by filtration. The bacteria were separated from the filtrate by centrifugation at 5,000 g. The bacterial fraction was washed once with 100 ml 0.1M Na 4 P 2 O 7 (pH 7) and once with 100 ml 0.15M NaCl, 10 mM EDTA (Saline EDTA) and, after centrifugation at 5,000 g, was resuspended in 25 ml Saline EDTA. By addition of 1 mg/ml lysozyme and subsequent incubation for 30 minutes at 37° C., the bacteria were lysed with sodium dodecyl sulfate (SDS) in a final concentration of 1%. In order to remove most of the humic substances still present in the soil, further purification can be achieved by ion exchange chromatography and hydroxylapatite chromatography or pronase, RNase treatment and extraction with phenol. As described with reference to the gene probe test procedure, the DNA was fixed to nitrocellulose or nylon membranes and the hybridization reaction was carried out with the Boehringer/Mannheim digoxigenin test kit. The nitrosomonas-specific DNA concentration or cell titer was quantitatively evaluated from the color intensity of the 5-bromo-4-chloro-3-indolyl nitroblue tetrazolium complex of the slot blots. TABLE 1______________________________________Molecular characterization of nitrosomonas clonesClone code Vector Insert [KB] Strain______________________________________256/15 pBR 322 2.7 Nitrosomonas256/32 pBR 322 5.8 Nitrosomonas256/36 pBR 322 2.3 Nitrosomonas256/39 pBR 322 1.3 Nitrosomonas258/21 pBR 322 3.9 Nitrosomonas258/22 pBR 322 5.9 Nitrosomonas258/23 pBR 322 3.3 Nitrosomonas258/27 pBR 322 21.6 Nitrosomonas258/29 pBR 322 6.0 Nitrosomonas258/33 pBR 322 3.4 Nitrosomonas258/34 pBR 322 7.1 Nitrosomonas258/35 pBR 322 7.5 Nitrosomonas323/9A pSPT 19 6.0 Nitrosomonas323/13B pSPT 19 6.0 Nitrosomonas322/9A pSK 6.0 Nitrosomonas322/10B pSK 6.0 Nitrosomonas______________________________________ Nitrosomonas DNA clones as BamHI fragments in the E. coli vector pBR 322 into E. coli 5K or AG1. The genomic DNA was isolated from the strain Nitrosomonas europaea 9718 and cloned. The 6 kb gene probe from 258/29 was recloned in both orientations into the vectors pSPT19 and pSK Bluescript. TABLE 2______________________________________Specificity of the nitrosomonas gene probe Degrada- Hybridization withStrain tion of 0.2kb 0.3kb 0.5kb 0.7kb 1.7kb______________________________________Nm. europaea Ammonia + + + + ++Nm. spec. 41-3/BE Ammonia ++ ++ ++ ++ +++Nm. spec. LA33 Ammonia ++ ++ ++ ++ +++Nm. spec. 41-3/GB Ammonia + + + + ++Nm. spec. 41-3/RW Ammonia + + + + ++Nm. spec. A 83 Ammonia + + + + ++Nm. spec. A 13 Ammonia + + + + ++N1. multiformis Ammonia - - - - -Nb. agilis Nitrite - - - - -Th. pantotropha Sulfur - - - - -Tb. novellus Sulfur - - - - -Tb. perometab Sulfur - - - - -Tb. acidophilus Sulfur - - - - -Alc. faccalis - - - - -Str. facalis - - - - -Staph. capitis - - - - -Kl. planticola - - - - -Microb. lacticum - - - - -E. coli 5k - - - - -P. spec 61-Tol4 Toluene - - - - -P. syringae 50-16 Sulfonic - - - - - acidP. putida 82-1 Nitro- - - - - - benz.Ps. putida NCIB Naphtha- - - - - -12042 leneBr. spec. 233 Poly- - - - - - cyclesAlcal. spec. Benzene - - - - -67-1.4R4Ps. spec. 67-D3/2 Benzene - - - - -M. spec. 1.2/2 Di- - - - - - chlorob.______________________________________ __________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 1(2) INFORMATION FOR SEQ ID NO: 1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 1722 bp(B) TYPE: Nucleotide(C) STRANDEDNESS: Double(D) TOPOLOGY: Linear(ii) MOLECULE TYPE: Genomic DNA(xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:TTAGAAGTAATGAGCCCATGGCTATTTGCCGCGCATAAACAT42MetSerProTrpLeuPheAlaAlaHisLysHisTTTATCCAGTTCAGCCAGGCTGATTTCAAACCAGGTAGG81PheIleGlnPheSer GlnAlaAspPheLysProGlyArgTCGGCCGTGATTGCATTGATCCGAGCGCTCGGTTACTTC120SerAlaValIleAlaLeuIleArgAlaLeuGlyTyrPheCATTTTGCGCAGAGTTCATTCATTTCAATCAGCGTTAA T159HisPheAlaGlnSerSerPheIleSerIleSerValAsnTGCCGGTTAGCGCGAACGGCACCGTGACAGGCCATGGTG198CysArgLeuAlaArgThrAlaProGlnAlaMetValGCCAGTAATTCATTA CDACGGGCGGCAAGCAGTTGAGCG237AlaSerAsnSerLeuXaaArgAlaAlaSerSerAlaGGATCGCCATTCCTGATTTCATCCAGCAGAGCACGTACC276GlySerProPheLeuIleSerSerSerArgAlaA rgThrAGTTTCGCATCAGCATGCTGCAGTGTGGCGGGGACTGTG315SerPheAlaSerAlaCysCysSerValAlaGlyThrValCGTATAACAAGTGTGGTAGCGGACAGCGTGCTCACTTCA354ArgIleThrSer ValValAlaAspSerValLeuThrSerAAACACAGTTGCTGCAAAAGCGCCTGATTTTCCTCCACT393LysHisSerCysCysLysSerAlaPheSerSerThrGTCGCGATGTCGAGGCTATCTGCGTGAAATGTAA CCGGT432ValAlaMetSerArgLeuSerAlaAsnValThrGlyATCAGCAATCGGTTGTGCGGATAATACTTGTTGATCCAG471IleSerAsnArgLeuCysGlyTyrLeuLeuIleGlnTTGTGTCTTCAA CTGCTCGTAGACAATGCGTTCGTGCGC510LeuCysLeuGlnLeuLeuValAspAsnAlaPheValArgGGCGTGCATGTCTACAATCACCAATCCTTTTTGGTTTTG549GlyValHisValTyrAsnHisGlnSerPhe LeuValLeuCGCCAGGATATAGATGCCGCGAAGTGCCCCAACGCAAAG588ArgGlnAspIleAspAlaAlaLysCysProAsnAlaLysCCCAGCGGGGGCATAGCCGAATTTTCATCGCTTTCTCCT627ProSerGl yGlyIleAlaGluPheSerSerLeuSerProTCCCCGGTTTGTCGAGGTTGATTTTGTATGGCAGTGGCG666SerProValCysArgGlyPheCysMetAlaValAlaCCGGATTCTCCGCCGGATAGAACCTGATAA AAGTTAAAA705ProAspSerProProAspArgThrLysLeuLysGGGTGCGCCACCCTTTCTGATGACAGCCGTGCTTGCCTG744GlyCysAlaThrLeuSerAspAspSerArgAlaCysLeuGGGTAGTT CAACGTCCACAGCCGGTGTAAAACCGGTGCG783GlyPheAsnValHisSerArgCysLysThrGlyAlaCGTTGGATCAACAGATGCATCCTGCGTACCTGGCCACAC822ArgTrpIleAsnArgCysIleLeuArg ThrTrpProHisGGCCCCAACAGGAGAGGAGGATGCTACAGCCGAGCGGGG861GlyProAsnArgArgGlyGlyCysTyrSerArgAlaGlyTAGAGCCAGCGCCTTGTGACGCCGTGGTAAATAAATTGG900S erGlnArgLeuValThrProTrpIleAsnTrpTGGATGGCCCGCTTCGGCGAAAGCGACTACGTTTCGTCG939TrpMetAlaArgPheGlyGluSerAspTyrValSerSerATGTACGTTGACATCCACCTGTTCAGG ATCGATCGCCAG978MetTyrValAspIleHisLeuPheArgIleAspArgGlnATACAGCACGAAAGCGGCATGACGATCAAGGTGCAGCAC1017IleGlnHisGluSerGlyMetThrIleLysValGlnHisATCA CGATAGCTTCGCGCAGGGCATGGGTAATCAGCTTG1056IleThrIleAlaSerArgArgAlaTrpValIleSerLeuTCGCGGATGAAGCGTCCGTTAACAAAAAAATACTGCATG1095SerArgMetLysArgProLeuTh rLysLysTyrCysMetTCGCGGGTGGCGCGTGAATACGCGGGCAATGCCAGCATC1134SerArgValAlaArgGluTyrAlaGlyAsnAlaSerIleCCCTGCAAACCGATGCCGGCGGATTGTTCGTCCATCCAG1173 ProCysLysProMetProAlaAspCysSerSerIleGlnGTAGCCGNTCCGGCAAATTCCTCGCCAAGTACGGCTCCG1212ValAlaXaaProAlaAsnSerSerProSerThrAlaProATACGCTCTGCAGCCTCTGCTGC CTGCCAGTGCTGCGCA1251IleArgSerAlaAlaSerAlaAlaCysGlnCysCysAlaGGTTTCCATTGTGCCGCAGCGTAAAGGTAATATCAGCGT1290GlyPheHisCysAlaAlaAlaArgTyrGlnArg GGGAAAGTGCCATCCGCCGAAAAACTTCTTCGCAGTGGG1329GlyLysValProSerAlaGluLysLeuLeuArgSerGlyCAAACTCTGTAGCTTCTGTTTTAAGAAATTTGCGGCGGG1368GlnThrLeuLeuLeuP heGluIleCysGlyGlyCAGGCAGGTTGAAAAACAGATCCCGGACTTCAACCGTAG1407GlnAlaGlyLysThrAspProGlyLeuGlnProTGCCCGCCATGTGGGATGAAGGCTCCGGCGACATTAACG1446 CysProProCysGlyMetLysAlaProAlaThrLeuThrTGTCCCCTCACTGCGGATTTCCCAGGCATGTTTGCCAGC1485CysProLeuThrAlaAspPheProGlyMetPheAlaSerGGGTTGATGACTGATGAGCGAC AAATACGAAACTGACGC1524GlyLeuMetThrAspGluArgGlnIleArgAsnArgGATACTGGCCAGCCCTTCCCCCCGGAATCCCAGGCTGGT1563AspThrGlyGlnProPheProProGluSerGlnAlaGly GATGCTGTGCAAATCCTCCTGGCTGGCAATTTTGCTGGT1602AspAlaValGlnIleLeuLeuAlaGlyAsnPheAlaGlyTGCGTGACGTGTAAGTGCAAGCGGCAGTTCTTCTGCGGG1641CysValThrCysLysCys LysArgGlnPhePheCysGlyAATGCCGCTGCCGTTATCGGTCACACGGATCAGTTTCAA1680AsnAlaAlaAlaValIleGlyHisThrAspGlnPheGlnTCCACCCTGTGCGATATTGACCGTAATCTCAGTCGCACC1 719SerThrLeuCysAspIleAspArgAsnLeuSerArgThrGGC1722Gly Literature 1. "Autrophic Nitrification in Bacteria", J. I. Prosser, Adv. in Microbiol Physiol, 30, 125-177 (1989) 2. Molecular Cloning A Laboratory Manual, J. Sambrook, E. F. Fritsch, T. Maniatis, Cold Spring Harbor Laboratory Press (1989) 3. "A Technique for Radiolabeling DNA Restriction Endonuclease Fragments to High Specific Activity" A. P. Feinberg and B. Vogelstein, Anal Biochem 132, 6 (1983) 4. "Isolation of Bacterial DNA from Soil," V. L. Torsvik, Soil Biol. Biochem. 12, 10-21 (1980) 5. "DNA Sequencing with Chain-Terminating Inhibitors" F. Sanger, S. Nichlen, A. R. Coulson, P .N .A. S. 7×, 5463 (1977) 6. "Deoxynucleoside Phosphoramidites; A New Class of Key Intermediates for Deoxypolynucleotide Synthesis", C. L. Beaucage and M. H. Caruthers, Tetrahedron Letters 22, 1859-1862 (1981)

For the detection and quantitative determination of nitrosomonas strains in wastewaters and soils, a gene probe is used which, by virtue of its complementary sequences, only hybridizes with parts of the genome of nitrosomonas strains from wastewater or soil samples and does not produce a positive hybridization signal with parts of the genome of other bacteria and the hybridized nucleic acid is quantitatively determined by means of a known label of the gene probe and thus provides a direct measure of the content of nitrosomonas strains in the wastewater or soil sample.