Breast MR imaging with high spectral and spatial resolutions : preliminary experience The authors evaluated magnetic resonance -LRB- MR -RRB- imaging with high spectral and spatial resolutions -LRB- HSSR -RRB- of water and fat in breasts of healthy volunteers -LRB- n = 6 -RRB- and women with suspicious lesions -LRB- n = 6 -RRB- . Fat suppression , edge delineation , and image texture were improved on MR images derived from HSSR data compared with those on conventional MR images . HSSR MR imaging data acquired before and after contrast medium injection showed spectrally inhomogeneous changes in the water resonances in small voxels that were not detectable with conventional MR imaging

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B O B I O O O O O O B I O B I O O B I O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O B I O B I O O O O O O O O

healthy volunteers
edge delineation
image texture
contrast medium injection
water resonances
small voxels
women
suspicious lesions
fat suppression

breast magnetic resonance imaging
high spectral spatial resolutions
magnetic resonance images
magnetic resonance imaging data


Existence theorems for nonconvex problems of variational calculus A solution to a variational calculus problem is studied under the conditions of integrant convexity . The existence theorem is proved . As an example , a function is given , which satisfies all the conditions of the theorem but is not convex

B I O B I O B I O O O O B I O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O

existence theorems
nonconvex problems
variational calculus
integrant convexity


An ACL for a dynamic system of agents In this article we present the design of an ACL for a dynamic system of agents . The ACL includes a set of conversation performatives extended with operations to register , create , and terminate agents . The main design goal at the agent-level is to provide only knowledge-level primitives that are well integrated with the dynamic nature of the system . This goal has been achieved by defining an anonymous interaction protocol which enables agents to request and supply knowledge without considering symbol-level issues concerning management of agent names , routing , and agent reachability . This anonymous interaction protocol exploits a distributed facilitator schema which is hidden at the agent-level and provides mechanisms for registering capabilities of agents and delivering requests according to the competence of agents . We present a formal specification of the ACL and of the underlying architecture , exploiting an algebra of actors , and illustrate it with the help of a graphical notation . This approach provides the basis for discussing dynamic primitives in ACL and for studying properties of dynamic multi agent systems , for example concerning the behavior of agents and the correctness of their conversation policies

O B O O B I I I O O O O O O O O O B O O B I I I O O B O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O B O O O O O O O O O O O O O O O O O O O O O O B I I O O B I O O O O O O O O O O O O O O B O O O O O O O O B O O O O O O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O B O O O O O O O

acl
dynamic system of agents
agents
distributed facilitator
actors
anonymous interaction protocol

system of agents
agent communication languages
dynamic system


Design and modeling of an interval-based ABR flow control protocol A novel flow control protocol is presented for availability bit rate -LRB- ABR -RRB- service in asynchronous transfer mode -LRB- ATM -RRB- networks . This scheme features periodic explicit rate feedback that enables precise allocation of link bandwidth and buffer space on a hop-by-hop basis to guarantee maximum throughput , minimum cell loss , and high resource efficiency . With the inclusion of resource management cell synchronization and consolidation algorithms , this protocol is capable of controlling point-to-multipoint ABR services within a unified framework . The authors illustrate the modeling of single ABR connection , the interaction between multiple ABR connections , and the constraints applicable to flow control decisions . A loss-free flow control mechanism is presented for high-speed ABR connections using a fluid traffic model . Supporting algorithms and ATM signaling procedures are specified , in company with linear system modeling , numerical analysis , and simulation results , which demonstrate its performance and cost benefits in high-speed backbone networking scenarios

B O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I I O O O O O O O O O O O O O O O O B I O B I I O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O B I I O O O O O B O O O O O O O O O B O B I O O B O O O O O O O O O O O O O O

modeling
design
periodic explicit rate feedback
maximum throughput
minimum cell loss
high resource efficiency
flow control decisions
fluid traffic model
signaling
numerical analysis
simulation

interval-based abr flow control protocol

resource management cell synchronization algorithms

resource management cell consolidation algorithms


A novel preterm respiratory mechanics active simulator to test the performances of neonatal pulmonary ventilators A patient active simulator is proposed which is capable of reproducing values of the parameters of pulmonary mechanics of healthy newborns and preterm pathological infants . The implemented prototype is able to : -LRB- a -RRB- let the operator choose the respiratory pattern , times of apnea , episodes of cough , sobs , etc. , -LRB- b -RRB- continuously regulate and control the parameters characterizing the pulmonary system ; and , finally , -LRB- c -RRB- reproduce the attempt of breathing of a preterm infant . Taking into account both the limitation due to the chosen application field and the preliminary autocalibration phase automatically carried out by the proposed device , accuracy and reliability on the order of 1 % is estimated . The previously indicated value has to be considered satisfactory in light of the field of application and the small values of the simulated parameters . Finally , the achieved metrological characteristics allow the described neonatal simulator to be adopted as a reference device to test performances of neonatal ventilators and , more specifically , to measure the time elapsed between the occurrence of a potentially dangerous condition to the patient and the activation of the corresponding alarm of the tested ventilator

O O B I I I I O O O O O B I I O B I I O O O O O O O O O O O O O O O B I O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O B O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

apnea times
respiratory diseases
ventilatory support
intensive care equipment
electronic unit
pneumatic/mechanical unit
software control
double compartment model
artificial trachea
pressure transducer
variable clamp resistance
upper airway resistance
compliance


Changes in the entropy and the Tsallis difference information during spontaneous decay and self-organization of nonextensive systems A theoretical-information description of self-organization processes during stimulated transitions between stationary states of open nonextensive systems is presented . S/sub q / - and I/sub q / - theorems on changes of the entropy and Tsallis difference information measures in the process of evolution in the space of control parameters are proved . The entropy and the Tsallis difference information are derived and their new extreme properties are discussed

O O O B O O B I I O B I O O O B I O O O O O O O B I O O O O O B I O O O O O O O O O O O O O O O O O B O B I I O O O O O O O O O O B I O O O O B O O B I I O O O O O O O O O

entropy
tsallis difference information
spontaneous decay
nonextensive systems
stimulated transitions
control parameters

self-organization
information measures
nonextensive statistical mechanics


Linear , parameter-varying control and its application to a turbofan engine This paper describes application of parameter-dependent control design methods to a turbofan engine . Parameter-dependent systems are linear systems , whose state-space descriptions are known functions of time-varying parameters . The time variation of each of the parameters is not known in advance , but is assumed to be measurable in real-time . Three linear , parameter-varying -LRB- LPV -RRB- approaches to control design are discussed . The first method is based on linear fractional transformations which relies on the small gain theorem for bounds on performance and robustness . The other methods make use of either a single -LRB- SQLF -RRB- or parameter-dependent -LRB- PDQLF -RRB- quadratic Lyapunov function to bound the achievable level of performance . The latter two techniques are used to synthesize controllers for a high-performance turbofan engine . A LPV model of the turbofan engine is constructed from Jacobian linearizations at fixed power codes for control design . The control problem is formulated as a model matching problem in the H/sub infinity / and LPV framework . The objective is decoupled command response of the closed-loop system to pressure and rotor speed requests . The performance of linear , H/sub infinity / point designs are compared with the SQLF and PDQLF controllers . Nonlinear simulations indicate that the controller synthesized using the SQLF approach is slightly more conservative than the PDQLF controller . Nonlinear simulations with the SQLF and PDQLF controllers show very robust designs that achieve all desired performance objectives

O O O O O O O O O B I O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B I O O O B I O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O B I O O O O O O O B I I O O O O O O

turbofan engine
linear fractional transformations
small gain theorem
jacobian linearizations
decoupled command response
model matching problem
nonlinear simulations
very robust designs

parameter-dependent quadratic lyapunov function


Optimal strategies for a semi-Markovian inventory system Control for a semi-Markovian inventory system is considered . Under general assumptions on system functioning , conditions for existence of an optimal nonrandomized Markovian strategy are found . It is shown that under some additional assumptions on storing conditions for the inventory , the optimal strategy has a threshold -LRB- s , S -RRB- - frame

B I O O O O O O O O O O O O O O O O O O B I O O O O O O B I I I O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O

optimal nonrandomized markovian strategy


Multichannel scaler for general statistical analysis of dynamic light scattering A four channel scaler for counting applications has been designed and built using a standard high transfer rate parallel computer interface bus parallel data card . The counter section is based on standard complex programmable logic device integrated circuits . With a 200 MHz Pentium based host PC a sustained counting and data transfer with channel widths as short as 200 ns for a single channel is realized . The use of the multichannel scaler is demonstrated in dynamic light scattering experiments . The recorded traces are analyzed with wavelet and other statistical techniques to obtain transient changes in the properties of the scattered light

B I O B I I O B I I O B I I O O O O O O O O O O B I I I I I I O O O O O O O O O O O O B I I I O O O O O B I B I I I O O O O O O O O O O O O B I O O O O O O O O O O O B I O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O

correlation spectroscopy
optical spectroscopic techniques
photon signal statistical properties
interface bus parallel data card
standard cpld ics
windowed fourier transform


To commit or not to commit : modeling agent conversations for action Conversations are sequences of messages exchanged among interacting agents . For conversations to be meaningful , agents ought to follow commonly known specifications limiting the types of messages that can be exchanged at any point in the conversation . These specifications are usually implemented using conversation policies -LRB- which are rules of inference -RRB- or conversation protocols -LRB- which are predefined conversation templates -RRB- . In this article we present a semantic model for specifying conversations using conversation policies . This model is based on the principles that the negotiation and uptake of shared social commitments entail the adoption of obligations to action , which indicate the actions that agents have agreed to perform . In the same way , obligations are retracted based on the negotiation to discharge their corresponding shared social commitments . Based on these principles , conversations are specified as interaction specifications that model the ideal sequencing of agent participations negotiating the execution of actions in a joint activity . These specifications not only specify the adoption and discharge of shared commitments and obligations during an activity , but also indicate the commitments and obligations that are required -LRB- as preconditions -RRB- or that outlive a joint activity -LRB- as postconditions -RRB- . We model the Contract Net Protocol as an example of the specification of conversations in a joint activity

O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O B O O O O O O O O O B I I O O B I O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

interacting agents
specifications
rules of inference
conversation protocols
social commitments
conversation templates

autonomous agents
speech acts
software agents


Predictive control of a high temperature-short time pasteurisation process Modifications on the dynamic matrix control -LRB- DMC -RRB- algorithm are presented to deal with transfer functions with varying parameters in order to control a high temperature-short time pasteurisation process . To control processes with first order with pure time delay models whose parameters present an exogenous variable dependence , a new method of free response calculation , using multiple model information , is developed . Two methods , to cope with those nonlinear models that allow a generalised Hammerstein model description , are proposed . The proposed methods have been tested , both in simulation and in real cases , in comparison with PID and DMC classic controllers , showing important improvements on reference tracking and disturbance rejection

B I O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O B I I O O O O B I I O O O O O B I I O O B I I O O O O O O O O O O O B I O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O B I

generalised hammerstein model description


Vacuum-compatible vibration isolation stack for an interferometric gravitational wave detector TAMA300 Interferometric gravitational wave detectors require a large degree of vibration isolation . For this purpose , a multilayer stack constructed of rubber and metal blocks is suitable , because it provides isolation in all degrees of freedom at once . In TAMA300 , a 300 m interferometer in Japan , long-term dimensional stability and compatibility with an ultrahigh vacuum environment of about 10/sup -6 / Pa are also required . To keep the interferometer at its operating point despite ground strain and thermal drift of the isolation system , a thermal actuator was introduced . To prevent the high outgassing rate of the rubber from spoiling the vacuum , the rubber blocks were enclosed by gas-tight bellows . Using these techniques , we have successfully developed a three-layer stack which has a vibration isolation ratio of more than 10/sup 3 / at 300 Hz with control of drift and enough vacuum compatibility

O B I I O O O O O O O B I I I O O O O O O O O O O O O O B I O O O O B I O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O B I O B I O B I O O O O O O B I O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B I

interferometric gravitational wave detectors

tama300 interferometer
long-term dimensional stability
gas-tight bellows
rubber outgassing
10/sup -6/ pa


The BLISS programming language : a history The BLISS programming language was invented by William A. Wulf and others at Carnegie-Mellon University in 1969 , originally for the DEC PDP-10 . BLISS-10 caught the interest of Ronald F. Brender of DEC -LRB- Digital Equipment Corporation -RRB- . After several years of collaboration , including the creation of BLISS-11 for the PDP-11 , BLISS was adopted as DEC 's implementation language for use on its new line of VAX computers in 1975 . DEC developed a completely new generation of BLISSs for the VAX , PDP-10 and PDP-11 , which became widely used at DEC during the 1970s and 1980s . With the creation of the Alpha architecture in the early 1990s , BLISS was extended again , in both 32 - and 64-bit flavors . BLISS support for the Intel IA-32 architecture was introduced in 1995 and IA-64 support is now in progress . BLISS has a number of unusual characteristics : it is typeless , requires use of an explicit contents of operator -LRB- written as a period or ` dot ' -RRB- , takes an algorithmic approach to data structure definition , has no goto , is an expression language , and has an unusually rich compile-time language . This paper reviews the evolution and use of BLISS over its three decade lifetime . Emphasis is on how the language evolved to facilitate portable programming while retaining its initial highly machine-specific character . Finally , the success of its characteristics are assessed

O B I I O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O

bliss programming language
portable programming
data structure definition

machine-oriented language
system implementation language
compile-time language


A six-degree-of-freedom precision motion stage This article presents the design and performance evaluation of a six-degree-of-freedom piezoelectrically actuated fine motion stage that will be used for three dimensional error compensation of a long-range translation mechanism . Development of a single element , piezoelectric linear displacement actuator capable of translations of 1.67 mu m with 900 V potential across the electrodes and under a 27.4 N axial load and 0.5 mm lateral distortion is presented . Finite element methods have been developed and used to evaluate resonant frequencies of the stage platform and the complete assembly with and without a platform payload . In general , an error of approximately 10.0 % between the finite element results and the experimentally measured values were observed . The complete fine motion stage provided approximately + or-0 .93 mu m of translation and + or-38 .0 mu rad of rotation in all three planes of motion using an excitation range of 1000 V . An impulse response indicating a fundamental mode resonance at 162 Hz was measured with a 0.650 kg payload rigidly mounted to the top of the stage

O O O O O O O O O B O B I O O O B I I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O B I O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O B I O O B I I O B I O O O O O O O O O O O O O O O

single element piezoelectric linear displacement actuator


On the accuracy of polynomial interpolation in Hilbert space with disturbed nodal values of the operator The interpolation accuracy of polynomial operators in a Hilbert space with a measure is estimated when nodal values of these operators are given approximately

O O O O B I O B I O B I I O O O O O O O B I O O B I O O O O O O O O O O O O O O

polynomial interpolation
hilbert space
disturbed nodal values
polynomial operators


Optimal time of switching between portfolios of securities Optimal time of switching between several portfolios of securities are found for the purpose of profit maximization . Two methods of their determination are considered . The cases with three and n portfolios are studied in detail

B I O O O B I I B I O O O O B I I O O O O O O B I O O O O O O O O O O O O O O O O O O O O

optimal time
portfolios of securities
profit maximization


Multiple comparison methods for means Multiple comparison methods -LRB- MCMs -RRB- are used to investigate differences between pairs of population means or , more generally , between subsets of population means using sample data . Although several such methods are commonly available in statistical software packages , users may be poorly informed about the appropriate method -LRB- s -RRB- to use and/or the correct way to interpret the results . This paper classifies the MCMs and presents the important methods for each class . Both simulated and real data are used to compare the methods , and emphasis is placed on a correct application and interpretation . We include suggestions for choosing the best method . Mathematica programs developed by the authors are used to compare MCMs . By taking the advantage of Mathematica 's notebook structure , all interested student can use these programs to explore the subject more deeply

O O O O O O O O O O O O O O O O O O O B I O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

multiple comparison procedures
error rate
single-step procedures
step-down procedures
sales management
pack-age design


Tool and process improvements from MFC control system technology A new approach to MFC calibration links the physical parameters of nitrogen to the physical characteristics of various process gases . This precludes the conventional need for surrogate gases . What results is a physics-based tuning algorithm and enhanced digital control system that enables rearranging and gas change of digital MFCs . The end result should be better process control through more accurate gas flow . The new method also decreases the number of MFC spare parts required to back up a fab

O O O O O B I I I O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O B I O O O O O O O O O O O O O O O O O B I O O O B I O O O O O O O O O O O O O O O O O O

mfc control system technology
calibration
tuning algorithm
digital control
process control
gas flow

process gas
surrogate gas
semiconductor fab
tool technology
mass flow controller
n/sub 2/


Component support in PLT scheme PLT Scheme -LRB- DrScheme and MzScheme -RRB- supports the Component Object Model -LRB- COM -RRB- standard with two pieces of software . The first piece is MzCOM , a COM class that makes a Scheme evaluator available to COM clients . With MzCOM , programmers can embed Scheme code in programs written in mainstream languages such as C++ or Visual BASIC . Some applications can also be used as MzCOM clients . The other piece of component-support software is MysterX , which makes COM classes available to PLT Scheme programs . When needed , MysterX uses a programmable Web browser to display COM objects . We describe the technical issues encountered in building these two systems and sketch some applications

O O O B I B I O O O O O O O B I I O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O B I O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O

plt scheme
component object model
mzcom
web browser


Breast cancer : effectiveness of computer-aided diagnosis-observer study with independent database of mammograms Evaluates the effectiveness of a computerized classification method as an aid to radiologists reviewing clinical mammograms for which the diagnoses were unknown to both the radiologists and the computer . Six mammographers and six community radiologists participated in an observer study . These 12 radiologists interpreted , with and without the computer aid , 110 cases that were unknown to both the 12 radiologist observers and the trained computer classification scheme . The radiologists ' performances in differentiating between benign and malignant masses without and with the computer aid were evaluated with receiver operating characteristic -LRB- ROC -RRB- analysis . Two-tailed P values were calculated for the Student t test to indicate the statistical significance of the differences in performances with and without the computer aid . When the computer aid was used , the average performance of the 12 radiologists improved , as indicated by an increase in the area under the ROC curve -LRB- A/sub z / -RRB- from 0.93 to 0.96 -LRB- P < .001 -RRB- , by an increase in partial area under the ROC curve -LRB- / sub 0.9 / 0A ' / sub z / -RRB- from 0.56 to 0.72 -LRB- P < .001 -RRB- , and by an increase in sensitivity from 94 % to 98 % -LRB- P = .022 -RRB- . No statistically significant difference in specificity was found between readings with and those without computer aid -LRB- Delta + -0.014 ; P = .46 ; 95 % Cl : -0.054 , 0.026 -RRB- , where Delta is difference in specificity . When we analyzed results from the mammographers and community radiologists as separate groups , a larger improvement was demonstrated for the community radiologists . Computer-aided diagnosis can potentially help radiologists improve their diagnostic accuracy in the task of differentiating between benign and malignant masses seen on mammograms

B I O O O O O O O B I O O O O O O O B I I O O O O O O B I O O O O O O O O O O O O O O O B O O B I O O O B I O O O O O O O O O O B I O O O O O O O O O O B I O O B I I I O O O O B O O O O O B I O O O O B I O O O O O O O O O O O O O O O O O O B I I O O O B I O O O O B O O O O B I O O O B I O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B I O O O O O O O O O O O B I O O O O O O O O O B I O O O O O O O O B I O O O

computerized classification method
clinical mammograms
observer study
breast cancer
independent database
trained computer classification scheme
radiologist observers
malignant masses
student t test
statistical significance
performances
average performance
diagnostic accuracy
computer aid
mammographers
community radiologists

receiver operating characteristic analysis