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2205.12607 | Discontinuities cause essential spectrum | We study transfer operators associated to piecewise monotone interval transformations and show that the essential spectrum is large whenever the Banach space bounds $L^\infty$ and the transformation fails to be Markov. Constructing a family of Banach spaces we show that the lower bound on the essential spectral radius is optimal. Indeed, these Banach spaces realise an essential spectral radius as close as desired to the theoretical best possible case. | [
"Mathematics Archive->math.DS"
] | "2022-05-25T09:30:13Z" |
2209.14419 | Category-Level Global Camera Pose Estimation with Multi-Hypothesis Point Cloud Correspondences | Correspondence search is an essential step in rigid point cloud registration algorithms. Most methods maintain a single correspondence at each step and gradually remove wrong correspondances. However, building one-to-one correspondence with hard assignments is extremely difficult, especially when matching two point clouds with many locally similar features. This paper proposes an optimization method that retains all possible correspondences for each keypoint when matching a partial point cloud to a complete point cloud. These uncertain correspondences are then gradually updated with the estimated rigid transformation by considering the matching cost. Moreover, we propose a new point feature descriptor that measures the similarity between local point cloud regions. Extensive experiments show that our method outperforms the state-of-the-art (SoTA) methods even when matching different objects within the same category. Notably, our method outperforms the SoTA methods when registering real-world noisy depth images to a template shape by up to 20% performance. | [
"Computer Science Archive->cs.CV"
] | "2022-09-28T21:12:51Z" |
astro-ph/0304003 | The Halo Distribution of 2dF Galaxies | We use the clustering results obtained by Madgwick et al. (2003) for a sample of 96,791 2dF galaxies with redshift 0.01 \lt z \lt 0.15 to study the distribution of late-type and early-type galaxies within dark matter haloes of different mass. Within the framework of our models, galaxies of both classes are found to be as spatially concentrated as the dark matter within haloes even though, while the distribution of star-forming galaxies can also allow for some steeper profiles, this is drastically ruled out in the case of early-type galaxies. We also find evidence for morphological segregation, as late-type galaxies appear to be distributed within haloes of mass scales corresponding to groups and clusters up to about two virial radii, while passive objects show a preference to reside closer to the halo centre. If we assume a broken power-law of the form <N_{gal}(m)>=(m/m_0)^{alpha_1} for m_{cut}\le m<m_0 and <N_{gal}(m)>=(m/m_0)^{alpha_2} at higher masses to describe the dependence of the average number of galaxies within haloes on the halo mass, fits to the data show that star-forming galaxies start appearing in haloes of masses m_{cut}~10^{11}m_{sun}, much smaller than what is obtained for early-type galaxies (m_{cut}~10^{12.6}m_{sun}). In the high-mass regime m\ge m_0, <N_{gal}>$ increases with halo mass more slowly (alpha_2~0.7) in the case of late-type galaxies than for passive objects which present alpha_2~1.1. We stress that there is no degeneracy in the determination of the best functional forms for rho(r) and <N_{gal}>, as they affect the behaviour of the galaxy-galaxy correlation function on different scales. | [
"Physics Archive->astro-ph"
] | "2003-03-31T22:15:57Z" |
2306.05914 | A Nonlinear Instability Theory for a Wave System inducing Transition in Spiral Poiseuille Flows | This paper is on the effect of nonlinearity in the equations for propagation of disturbances on transition in the class of Spiral Poiseuille Flows. The problem is approached from the fundamental point of view of following the growth of initially infinitesimally small disturbances into their nonlinear stage when the effect of Reynolds stresses makes itself felt. To this end a rational scheme of an iterative solution method for the set of Generalised Nonlinear Orr-Sommerfeld, Squire and Continuity equations is proposed. The present proposal for Spiral Poiseuille Flows closely follows that put forth in 1971 by Stuart and Stewartson in their seminal papers on the influence of nonlinear effects during transition in bench-mark flows, which are the flow in the gap between concentric circular cylinders (Taylor instability), and in the plane walled channel flow. The basic feature of the proposed method is the introduction of an Amplitude Parameter and of a slow/long scale variable to account for the effect of growing disturbances within the framework of a rational iteration scheme. It is shown that the effect of amplified disturbances is captured, as in the bench-mark flows, by a Ginzburg-Landau type differential equation for an Amplitude Function in terms of suitably defined slow/long scale variables. However, the coefficients in this equation are numbers that depend upon the flow parameters of the Spiral Poiseuille Flow, which are the Reynolds Number, the Swirl Number, and the geometric parameter of transverse curvature of the flow geometry. | [
"Physics Archive->physics->physics.flu-dyn"
] | "2023-06-09T14:09:14Z" |
hep-th/0403156 | Regular S-Brane Backgrounds | We construct time-dependent S-brane solutions to the supergravity field equations in various dimensions which (unlike most such geometries) do not contain curvature singularities. The configurations we consider are less symmetric than are earlier solutions, with our simplest solution being obtained by a simple analytical continuation of the Kerr geometry. We discuss in detail the global structure and properties of this background. We then generalize it to higher dimensions and to include more complicated field configurations - like non vanishing scalars and antisymmetric tensor gauge potentials - by the usual artifice of applying duality symmetries. | [
"Physics Archive->gr-qc",
"Physics Archive->hep->hep-ph",
"Physics Archive->hep->hep-th"
] | "2004-03-15T19:17:04Z" |
1509.07531 | A practical method for the analysis of meteor spectra | The analysis of meteor spectra (photographic, CCD or video recording) is complicated by the fact that spectra obtained with objective gratings are curved and have a nonlinear dispersion. In this paper it is shown that with a simple image transformation the spectra can be linearized in such a way that individual spectra over the whole image plane are parallel and have a constant, linear dispersion. This simplifies the identification and measurement of meteor spectral lines. A practical method is given to determine the required image transformation. | [
"Physics Archive->astro-ph->astro-ph.IM"
] | "2015-09-24T20:38:53Z" |
1511.03534 | Central and medial quasigroups of small order | We enumerate central and medial quasigroups of order less than $128$ up to isomorphism, with the exception of those quasigroups that are isotopic to $C_4\times C_2^4$, $C_2^6$, $C_3^4$ or $C_5^3$. We give an explicit formula for the number of quasigroups that are affine over a finite cyclic group. | [
"Mathematics Archive->math.GR"
] | "2015-11-11T15:29:41Z" |
1704.06983 | Estimating the Region of Attraction Using Polynomial Optimization: a Converse Lyapunov Result | In this paper, we propose an iterative method for using SOS programming to estimate the region of attraction of a polynomial vector field, the conjectured convergence of which necessitates the existence of polynomial Lyapunov functions whose sublevel sets approximate the true region of attraction arbitrarily well. The main technical result of the paper is the proof of existence of such a Lyapunov function. Specifically, we use the Hausdorff distance metric to analyze convergence and in the main theorem demonstrate that the existence of an $n$-times continuously differentiable maximal Lyapunov function implies that for any $\epsilon>0$, there exists a polynomial Lyapunov function and associated sub-level set which together prove stability of a set which is within $\epsilon$ Hausdorff distance of the true region of attraction. The proposed iterative method and probably convergence is illustrated with a numerical example. | [
"Mathematics Archive->math.DS"
] | "2017-04-23T21:16:58Z" |
1405.3781 | Higgs Physics | This lecture discusses the Higgs boson sectors of the SM and the MSSM, in particular in view of the recently discovered particle at \sim 125.5 GeV. It covers aspects of Higgs physics at the LHC and the ILC. | [
"Physics Archive->hep->hep-ph"
] | "2014-05-15T09:47:17Z" |
cond-mat/0502353 | Critical wave-packet dynamics in the power-law bond disordered Anderson Model | We investigate the wave-packet dynamics of the power-law bond disordered one-dimensional Anderson model with hopping amplitudes decreasing as $H_{nm}\propto |n-m|^{-\alpha}$. We consider the critical case ($\alpha=1$). Using an exact diagonalization scheme on finite chains, we compute the participation moments of all stationary energy eigenstates as well as the spreading of an initially localized wave-packet. The eigenstates multifractality is characterized by the set of fractal dimensions of the participation moments. The wave-packet shows a diffusive-like spread developing a power-law tail and achieves a stationary non-uniform profile after reflecting at the chain boundaries. As a consequence, the time-dependent participation moments exhibit two distinct scaling regimes. We formulate a finite-size scaling hypothesis for the participation moments relating their scaling exponents to the ones governing the return probability and wave-function power-law decays. | [
"Physics Archive->cond-mat->cond-mat.dis-nn"
] | "2005-02-15T19:34:26Z" |
0704.1527 | Study of exotic hadrons in s-wave chiral dynamics | We study the exotic hadrons in s-wave scattering of the Nambu-Goldstone boson with a target hadron based on chiral dynamics. Utilizing the low energy theorem of chiral symmetry, we show that the s-wave interaction is not strong enough to generate bound states in exotic channels in flavor SU(3) symmetric limit, although the interaction is responsible for generating some nonexotic hadron resonances dynamically. We discuss the renormalization condition adopted in this analysis. | [
"Physics Archive->hep->hep-ph",
"Physics Archive->nucl->nucl-th"
] | "2007-04-12T06:03:57Z" |
0908.3933 | Absolute positions of 6.7-GHz methanol masers | The ATCA, MERLIN and VLA interferometers were used to measure the absolute positions of 35 6.7 GHz methanol masers to subarcsecond or higher accuracy. Our measurements represent essential preparatory data for Very Long Baseline Interferometry, which can provide accurate parallax and proper motion determinations of the star-forming regions harboring the masers. Our data also allow associations to be established with infrared sources at different wavelengths. Our findings support the view that the 6.7 GHz masers are associated with the earliest phases of high-mass star formation. | [
"Physics Archive->astro-ph->astro-ph.GA",
"Physics Archive->astro-ph->astro-ph.SR"
] | "2009-08-27T04:29:21Z" |
1901.10152 | Resonant multiple peaks in the induced gravitational waves | We identify analytically a multiple-peak structure in the energy-density spectrum of induced gravitational waves (GWs) generated at second-order from a primordial scalar perturbations also with multiple($n$) peaks at small scales $k_{*i}$. The energy-density spectrum of induced GWs exhibits at most $C_{n+1}^2$ and at least $n$ peaks at wave-vectors $k_{ij}\equiv(k_{*i}+k_{*j})/\sqrt{3}$ due to resonant amplification, and, under the narrow-width approximation, it contains an universal factor that can be interpreted as a result of momentum conservation. We also extend these discussions to the case of non-Gaussian perturbations. | [
"Physics Archive->astro-ph->astro-ph.CO",
"Physics Archive->gr-qc",
"Physics Archive->hep->hep-th"
] | "2019-01-29T08:02:22Z" |
2107.05011 | Dual Optimization for Kolmogorov Model Learning Using Enhanced Gradient Descent | Data representation techniques have made a substantial contribution to advancing data processing and machine learning (ML). Improving predictive power was the focus of previous representation techniques, which unfortunately perform rather poorly on the interpretability in terms of extracting underlying insights of the data. Recently, the Kolmogorov model (KM) was studied, which is an interpretable and predictable representation approach to learning the underlying probabilistic structure of a set of random variables. The existing KM learning algorithms using semi-definite relaxation with randomization (SDRwR) or discrete monotonic optimization (DMO) have, however, limited utility to big data applications because they do not scale well computationally. In this paper, we propose a computationally scalable KM learning algorithm, based on the regularized dual optimization combined with enhanced gradient descent (GD) method. To make our method more scalable to large-dimensional problems, we propose two acceleration schemes, namely, the eigenvalue decomposition (EVD) elimination strategy and an approximate EVD algorithm. Furthermore, a thresholding technique by exploiting the error bound analysis and leveraging the normalized Minkowski $\ell_1$-norm, is provided for the selection of the number of iterations of the approximate EVD algorithm. When applied to big data applications, it is demonstrated that the proposed method can achieve compatible training/prediction performance with significantly reduced computational complexity; roughly two orders of magnitude improvement in terms of the time overhead, compared to the existing KM learning algorithms. Furthermore, it is shown that the accuracy of logical relation mining for interpretability by using the proposed KM learning algorithm exceeds $80\%$. | [
"Computer Science Archive->cs.LG",
"Electrical Engineering and Systems Science Archive->eess.SP"
] | "2021-07-11T10:33:02Z" |
1912.05706 | Constraining the Neutron Star Mass-Radius Relation and Dense Matter Equation of State with NICER. I. The Millisecond Pulsar X-ray Data Set | We present the set of deep Neutron Star Interior Composition Explorer (NICER) X-ray timing observations of the nearby rotation-powered millisecond pulsars PSRs J0437-4715, J0030+0451, J1231-1411, and J2124-3358, selected as targets for constraining the mass-radius relation of neutron stars and the dense matter equation of state via modeling of their pulsed thermal X-ray emission. We describe the instrument, observations, and data processing/reduction procedures, as well as the series of investigations conducted to ensure that the properties of the data sets are suitable for parameter estimation analyses to produce reliable constraints on the neutron star mass-radius relation and the dense matter equation of state. We find that the long-term timing and flux behavior and the Fourier-domain properties of the event data do not exhibit any anomalies that could adversely affect the intended measurements. From phase-selected spectroscopy, we find that emission from the individual pulse peaks is well described by a single-temperature hydrogen atmosphere spectrum, with the exception of PSR J0437-4715, for which multiple temperatures are required. | [
"Physics Archive->astro-ph->astro-ph.HE"
] | "2019-12-12T00:04:42Z" |
1308.4464 | Remarks on the abelian ideals of a Borel subalgebra | Let $\frb$ be a fixed Borel subalgebra of a finite-dimensional complex simple Lie algebra $\frg$. The Shi bijection associates to every ad-nilpotent ideal $\fri$ of $\frb$ a region $V_{\fri}$. In this paper, we show that $\fri$ is abelian if and only if $V_{\fri}\cap 2A$ is empty, if and only if the volume of $V_{\fri}\cap 2A$ equals to that of $A$, where $A$ is the fundamental alcove of the affine Weyl group. For certain flag of abelian ideals, we record an ascending property of their associated regions. We also determine the maximal eigenvalue $m_{r-1}$ of the Casimir operator on $\wedge^{r-1} \frg$ and the corresponding eigenspace $M_{r-1}$, where $r$ is the number of positive roots. | [
"Mathematics Archive->math.RT"
] | "2013-08-21T01:30:49Z" |
1906.10119 | Yukawa Hierarchies in Global F-theory Models | We argue that global F-theory compactifications to four dimensions generally exhibit higher rank Yukawa matrices from multiple geometric contributions known as Yukawa points. The holomorphic couplings furthermore have large hierarchies for generic complex structure moduli. Unlike local considerations, the compact setup realizes these features all through geometry, and requires no instanton corrections. As an example, we consider a concrete toy model with $SU(5) \times U(1)$ gauge symmetry. From the geometry, we find two Yukawa points for the ${\bf 10}_{-2} \, \bar{\bf 5}_6 \, \bar{\bf 5}_{-4}$ coupling, producing a rank two Yukawa matrix. Our methods allow us to track all complex structure dependencies of the holomorphic couplings and study the ratio numerically. This reveals hierarchies of ${\cal O}(10^5)$ and larger on a full-dimensional subspace of the moduli space. | [
"Physics Archive->hep->hep-th"
] | "2019-06-24T17:59:45Z" |
2108.11453 | Mapping out the emergence of topological features in the highly alloyed topological Kondo insulators Sm$_{1-x}M_x$B$_6$ ($M$=Eu, Ce) | SmB6 is a strongly correlated material that has been attributed as a topological insulator and a Kondo insulator. Recent studies have found the topological surface states and low temperature insulating character to be profoundly robust against magnetic and non-magnetic impurities. Here, we use angle resolved photoemission spectroscopy to chart the evolution of topologically-linked electronic structure features versus magnetic doping and temperature in Sm$_{1-x}$M$_x$B$_6$ (M=Eu, Ce). Topological coherence phenomena are observed out to unprecedented ~30% Eu and 50% Ce concentrations that represent extreme nominal hole and electron doping, respectively. Theoretical analysis reveals that a recent re-designation of the topologically inverted band symmetries provides a natural route to reconciling the persistence of topological surface state emergence even as the insulating gap is lost through decoherence. | [
"Physics Archive->cond-mat->cond-mat.mtrl-sci",
"Physics Archive->cond-mat->cond-mat.str-el"
] | "2021-08-25T19:58:13Z" |
1908.00165 | Generalized Fault-Tolerance Topology Generation for Application Specific Network-on-Chips | The Network-on-Chips is a promising candidate for addressing communication bottlenecks in many-core processors and neural network processors. In this work, we consider the generalized fault-tolerance topology generation problem, where the link or switch failures can happen, for application-specific network-on-chips (ASNoC). With a user-defined number, K, we propose an integer linear programming (ILP) based method to generate ASNoC topologies, which can tolerate at most K faults in switches or links. Given the communication requirements between cores and their floorplan, we first propose a convex-cost-flow based method to solve a core mapping problem for building connections between the cores and switches. Second, an ILP based method is proposed to allocate K+1 switch-disjoint routing paths for every communication flow between the cores. Finally, to reduce switch sizes, we propose sharing the switch ports for the connections between the cores and switches and formulate the port sharing problem as a clique-partitioning problem Additionally, we propose an ILP-based method to simultaneously solve the core mapping and routing path allocation problems when considering physical link failures only. Experimental results show that the power consumptions of fault-tolerance topologies increase almost linearly with K because of the routing path redundancy. When both switch faults and link faults are considered, port sharing can reduce the average power consumption of fault-tolerance topologies with K = 1, K = 2 and K = 3 by 18.08%, 28.88%, and 34.20%, respectively. When considering only the physical link faults, the experimental results show that compared to the FTTG algorithm, the proposed method reduces power consumption and hop count by 10.58% and 6.25%, respectively; compared to the DBG based method, the proposed method reduces power consumption and hop count by 21.72% and 9.35%, respectively. | [
"Computer Science Archive->cs.AR"
] | "2019-08-01T01:14:03Z" |
cond-mat/0301087 | Segregation and Phase Inversion in a Simple Granular System | The segregation and the phase inversion are investigated through a simple granular system which consists of only two inelastic hard spheres in a square box with an energy source. With the variation of the coefficient of restitution, the mass ratio between two spheres or the box size, we show that two types of segregated states and crossover between them are realized in such a small simple system. | [
"Physics Archive->cond-mat->cond-mat.soft"
] | "2003-01-08T03:50:20Z" |
1003.5151 | Coherent rings of differential operators | We consider the following question: When are rings of differential operators coherent? If $A$ is a finitely generated smooth domain over a field $k$ of characteristic $0$, then the ring $D$ of differential operators on $A$ is a Noetherian ring and a finitely generated $k$-algebra. However, when $k$ has characteristic $p > 0$ or when $A$ is singular, this is no longer true. In fact, Bernstein, Gelfand and Gelfand showed that for the cubic cone $A = k[x,y,z]/(x^3 + y^3 + z^3)$, the ring $D$ is neither Noetherian nor finitely generated if $k$ has characteristic $0$, and the same is true for the polynomial ring $A = k[x_1, \dots, x_n]$ if $k$ has characteristic $p > 0$. In this paper, we prove that the ring $D$ of differential operators on a finitely generated, smooth and connected algebra $A$ over a field $k$ of characteristic $p > 0$ is coherent, and conjecture that same holds for the cubic cone in characteristic $0$. We argue that the question of coherence is the more fundamental one, and use some interesting results of Bavula to study holonomic $D$-modules on $A = k[x_1, \dots, x_n]$ in characteristic $p > 0$. | [
"Mathematics Archive->math.RA"
] | "2010-03-26T14:50:10Z" |
2008.07165 | Analysing a built-in advantage in asymmetric darts contests using causal machine learning | We analyse a sequential contest with two players in darts where one of the contestants enjoys a technical advantage. Using methods from the causal machine learning literature, we analyse the built-in advantage, which is the first-mover having potentially more but never less moves. Our empirical findings suggest that the first-mover has an 8.6 percentage points higher probability to win the match induced by the technical advantage. Contestants with low performance measures and little experience have the highest built-in advantage. With regard to the fairness principle that contestants with equal abilities should have equal winning probabilities, this contest is ex-ante fair in the case of equal built-in advantages for both competitors and a randomized starting right. Nevertheless, the contest design produces unequal probabilities of winning for equally skilled contestants because of asymmetries in the built-in advantage associated with social pressure for contestants competing at home and away. | [
"Economics Archive->econ.EM"
] | "2020-08-17T09:07:14Z" |
1506.08225 | Thermoelectric Energy Harvesting Via Piezoelectric Material | Thermoelectric energy harvesters can have a much higher conversion efficiency by implementing quantum dots/wells between the high temperature region and the low temperature region. However they still suffer a limitation of the maximum output power, represented by the maximum $\Delta E$ (maximum energy gap of two quantum dots/wells layers). In this work, we use the piezoelectric material in the high temperature region, which has conceptually addressed the problem of the maximum power limitation. Full analysis of device physics including comparison with the existing technology and quantum simulation has been conducted to validate this concept. Results show that with the new concept, the maximum output power has been increased by at least an order of magnitude with the same power input and identical device dimensions. | [
"Physics Archive->cond-mat->cond-mat.mes-hall"
] | "2015-06-26T21:51:11Z" |
2001.08725 | On fluctuations of global and mesoscopic linear eigenvalue statistics of generalized Wigner matrices | We consider an $N$ by $N$ real or complex generalized Wigner matrix $H_N$, whose entries are independent centered random variables with uniformly bounded moments. We assume that the variance profile, $s_{ij}:=\mathbb{E} |H_{ij}|^2$, satisfies $\sum_{i=1}^Ns_{ij}=1$, for all $1 \leq j \leq N$ and $c^{-1} \leq N s_{ij} \leq c$ for all $ 1 \leq i,j \leq N$ with some constant $c \geq 1$. We establish Gaussian fluctuations for the linear eigenvalue statistics of $H_N$ on global scales, as well as on all mesoscopic scales up to the spectral edges, with the expectation and variance formulated in terms of the variance profile. We subsequently obtain the universal mesoscopic central limit theorems for the linear eigenvalue statistics inside the bulk and at the edges respectively. | [
"Mathematics Archive->math.PR"
] | "2020-01-23T18:35:42Z" |
1204.5521 | An integrable multicomponent quad equation and its Lagrangian formulation | We present a hierarchy of discrete systems whose first members are the lattice modified Korteweg-de Vries equation, and the lattice modified Boussinesq equation. The N-th member in the hierarchy is an N-component system defined on an elementary plaquette in the 2-dimensional lattice. The system is multidimensionally consistent and a Lagrangian which respects this feature, i.e., which has the desirable closure property, is obtained. | [
"Physics Archive->nlin->nlin.SI"
] | "2012-04-25T00:38:26Z" |
hep-th/0307071 | Where new gravitational physics comes from: M-theory? | It is suggested \cite{CDTT} that current cosmic acceleration arises due to modification of General Relativity by the terms with negative powers of curvature. We show that time-dependent (hyperbolic) compactifications of string/M-theory lead to the effective 4d gravity which naturally contains such terms. The same may be achieved in braneworld by the proper choice of the boundary action. Hence, such a model which seems to eliminate the need for dark energy may have the origin in M-theory. | [
"Physics Archive->astro-ph",
"Physics Archive->hep->hep-ph",
"Physics Archive->hep->hep-th"
] | "2003-07-08T09:38:55Z" |
1910.06090 | Glitches in neutron stars with magnetically decoupled core | The magnetically decoupled core model was proposed earlier as a way to solve the problem of inconsistency between the neutron star long-period precession and superfluid vortex pinning which is the base of most theories of pulsar glitches. It was assumed that the pinning takes place in the region of the neutron star core which, being magnetically decoupled, can rotate relative to the crust. In present work some aspects of the glitch spin-up stage in the framework of the proposed model are discussed. Estimated spin-up time-scales are compared with observational data. According to the estimations the Crab pulsar is likely posses a magnetically decoupling core region, while the results for the Vela pulsar is more controversial. | [
"Physics Archive->astro-ph->astro-ph.HE",
"Physics Archive->astro-ph->astro-ph.SR"
] | "2019-10-10T14:16:57Z" |
2211.14374 | On inclusion relations between weighted spaces of entire functions | We characterize the inclusions of weighted classes of entire functions in terms of the defining weights resp. weight systems. First we treat weights defined in terms of a so-called associated weight function where the weight(system) is based on a given sequence. The abstract weight function case is then reduced to the weight sequence setting by using the so-called associated weight sequence. As an application of the main statements we characterize closedness under point-wise multiplication of these classes. | [
"Mathematics Archive->math.CV",
"Mathematics Archive->math.FA"
] | "2022-11-25T21:08:20Z" |
1707.01488 | Measuring Reionization, Neutrino Mass, and Cosmic Inflation with BFORE | BFORE is a NASA high-altitude ultra-long-duration balloon mission proposed to measure the cosmic microwave background (CMB) across half the sky during a 28-day mid-latitude flight launched from Wanaka, New Zealand. With the unique access to large angular scales and high frequencies provided by the balloon platform, BFORE will significantly improve measurements of the optical depth to reionization tau, breaking parameter degeneracies needed for a measurement of neutrino mass with the CMB. The large angular scale data will enable BFORE to hunt for the large-scale gravitational wave B-mode signal, as well as the degree-scale signal, each at the r~0.01 level. The balloon platform allows BFORE to map Galactic dust foregrounds at frequencies where they dominate, in order to robustly separate them from CMB signals measured by BFORE, in addition to complementing data from ground-based telescopes. The combination of frequencies will also lead to velocity measurements for thousands of galaxy clusters, as well as probing how star-forming galaxies populate dark matter halos. The mission will be the first near-space use of TES multichroic detectors (150/217 GHz and 280/353 GHz bands) using highly-multiplexed mSQUID microwave readout, raising the technical readiness level of both technologies. | [
"Physics Archive->astro-ph->astro-ph.CO",
"Physics Archive->astro-ph->astro-ph.IM"
] | "2017-07-05T17:36:47Z" |
2104.12737 | The Puzzling Origin of Massive Compact Galaxies in MaNGA | We characterized the kinematics, morphology, and stellar population (SP) properties of a sample of massive compact quiescent galaxies (MCGs, $10 \lesssim \log M_\star$/$M_\odot \lesssim 11$ and $r_{\rm e} \sim 1-3 $kpc) in the MaNGA Survey, with the goal of constraining their formation, assembly history and assessing their relation with non-compact quiescent galaxies. We compared their properties with those of a control sample of median-sized quiescent galaxies ($r_{\rm e} \sim 4-8 $kpc) with similar effective velocity dispersions. MCGs have elevated rotational support, as evidenced by a strong anti-correlation between the Gauss-Hermite moment $h_3$ and $V/\sigma$. In contrast, 30$\%$ of control sample galaxies (CSGs) are slow rotators, and fast-rotating CSGs generally show a weak $h_3-V/\sigma$ anti-correlation. MCGs and CSGs have similar ages, but MCGs are more metal-rich and $\alpha$-enhanced. Both MCGs and CSGs have shallow negative metallicity gradients and flat [$\alpha$/Fe] gradients. On average, MCGs and CSGs have flat age gradients, but CSGs have a significantly larger dispersion of gradient values. The kinematics and SP properties of MCGs suggest that they experienced highly-dissipative gas-rich events, such as mergers, followed by an intense, short, and centrally concentrated burst of star formation, between 4 to 10 Gyr ago ($z\sim0.4-2$), and had a quiet accretion history since then. This sequence of events might be analogous to, although less extreme than, the compaction events which formed compact quiescent galaxies at $z \sim 2$. The small sizes of MCGs, and the high efficiency and short duration of their last star formation episode suggest that they are descendants of compact post-starburst galaxies. | [
"Physics Archive->astro-ph->astro-ph.GA"
] | "2021-04-26T17:29:25Z" |
2312.02448 | Time-Relative RTK-GNSS: GNSS Loop Closure in Pose Graph Optimization | A pose-graph-based optimization technique is widely used to estimate robot poses using various sensor measurements from devices such as laser scanners and cameras. The global navigation satellite system (GNSS) has recently been used to estimate the absolute 3D position of outdoor mobile robots. However, since the accuracy of GNSS single-point positioning is only a few meters, the GNSS is not used for the loop closure of a pose graph. The main purpose of this study is to generate a loop closure of a pose graph using a time-relative real-time kinematic GNSS (TR-RTK-GNSS) technique. The proposed TR-RTK-GNSS technique uses time-differential carrier phase positioning, which is based on carrier-phase-based differential GNSS with a single GNSS receiver. Unlike a conventional RTK-GNSS, we can directly compute the robot's relative position using only a stand-alone GNSS receiver. The initial pose graph is generated from the accumulated velocity computed from GNSS Doppler measurements. To reduce the accumulated error of velocity, we use the TR-RTK-GNSS technique for the loop closure in the graph-based optimization framework. The kinematic positioning tests were performed using an unmanned aerial vehicle to confirm the effectiveness of the proposed technique. From the tests, we can estimate the vehicle's trajectory with approximately 3 cm accuracy using only a stand-alone GNSS receiver. | [
"Computer Science Archive->cs.RO"
] | "2023-12-05T03:00:50Z" |
1003.5560 | Biases in mass estimates of dSph galaxies | Using a high resolution N-body simulation of a two-component dwarf galaxy orbiting in the potential of the Milky Way, we study two effects that lead to significant biases in mass estimates of dwarf spheroidal galaxies. Both are due to the strong tidal interaction of initially disky dwarfs with their host. The tidal stripping of dwarf stars leads to the formation of strong tidal tails that are typically aligned with the line of sight of an observer positioned close to the host center. The stars from the tails contaminate the kinematic samples leading to a velocity dispersion profile increasing with the projected radius and resulting in an overestimate of mass. The tidal stirring of the dwarf leads to the morphological transformation of the initial stellar disk into a bar and then a spheroid. The distribution of stars in the dwarf remains non-spherical for a long time leading to an overestimate of its mass if it is observed along the major axis and an underestimate if it seen in the perpendicular direction. | [
"Physics Archive->astro-ph->astro-ph.CO"
] | "2010-03-29T15:00:27Z" |
0811.3671 | Nonlinear dynamics of soft fermion excitations in hot QCD plasma III: Soft-quark bremsstrahlung and energy losses | In general line with our early works [Yu.A. Markov, M.A. Markova, Nucl. Phys. A770 (2006) 162; 784 (2007) 443] within the framework of a semiclassical approximation the general theory of calculation of effective currents and sources generating bremsstrahlung of an arbitrary number of soft quarks and soft gluons at collision of a high-energy color-charged particle with thermal partons in a hot quark-gluon plasma, is developed. For the case of one- and two-scattering thermal partons with radiation of one or two soft excitations, the effective currents and sources are calculated in an explicit form. In the model case of `frozen' medium, approximate expressions for energy losses induced by the most simple processes of bremsstrahlung of soft quark and soft gluon, are derived. On the basis of a conception of the mutual cancellation of singularities in the sum of so-called `diagonal' and `off-diagonal' contributions to the energy losses, an effective method of determining color factors in scattering probabilities, containing the initial values of Grassmann color charges, is suggested. The dynamical equations for Grassmann color charges of hard particle used by us early are proved to be insufficient for investigation of the higher radiative processes. It is shown that for correct description of these processes the given equations should be supplemented successively with the higher-order terms in powers of the soft fermionic field. | [
"Physics Archive->hep->hep-ph"
] | "2008-11-22T09:21:26Z" |
astro-ph/0307238 | First-order Fermi Particle Acceleration at Relativistic Shock Waves with a 'Realistic' Magnetic Field Turbulence Model | First-order Fermi acceleration process at a relativistic shock wave is investigated by means of Monte Carlo simulations involving numerical integration of particle equations of motion in a turbulent magnetic field near the shock. In comparison to earlier studies a few 'realistic' features of the magnetic field structure are included. The upstream field consists of a mean field component inclined at some angle to the shock normal and finite-amplitude perturbations imposed upon it. The perturbations are assumed to be static in the local plasma rest frame. We apply an analytic model for the turbulence with a flat or a Kolmogorov spectrum within a finite (wide) wave vector range. The magnetic field is continuous across the shock -- the downstream field structure is derived from the upstream one from the hydrodynamical shock jump conditions. We present and discuss the obtained particle spectra and angular distributions at mildly relativistic sub- and superluminal shocks. We show that particle spectra diverge from a simple power-law, an exact shape of the spectrum depends on both an amplitude of the magnetic field perturbations and the considered wave power spectrum. | [
"Physics Archive->astro-ph"
] | "2003-07-11T10:16:29Z" |
1910.03189 | Operatorial characterization of Majorana neutrinos | The Majorana neutrino $\psi_{M}(x)$ when constructed as a superposition of chiral fermions such as $\nu_{L} + C\overline{\nu_{L}}^{T}$ is characterized by $ ({\cal C}{\cal P}) \psi_{M}(x)({\cal C}{\cal P})^{\dagger} =i\gamma^{0}\psi_{M}(t,-\vec{x})$, and the CP symmetry describes the entire physics contents of Majorana neutrinos. Further specifications of C and P separately could lead to difficulties depending on the choice of C and P. The conventional $ {\cal C} \psi_{M}(x) {\cal C}^{\dagger} = \psi_{M}(x)$ with well-defined P is naturally defined when one constructs the Majorana neutrino from the Dirac-type fermion. In the seesaw model of Type I or Type I+II where the same number of left- and right-handed chiral fermions appear, it is possible to use the generalized Pauli-Gursey transformation to rewrite the seesaw Lagrangian in terms of Dirac-type fermions only; the conventional C symmetry then works to define Majorana neutrinos. In contrast, the "pseudo C-symmetry" $\nu_{L,R}(x)\rightarrow C\overline{\nu_{L,R}(x)}^{T}$ (and associated "pseudo P-symmetry"), that has been often used in both the seesaw model and Weinberg's model to describe Majorana neutrinos, attempts to assign a nontrivial charge conjugation transformation rule to each chiral fermion separately. But this common construction is known to be operatorially ill-defined and, for example, the amplitude of the neutrinoless double beta decay vanishes if the vacuum is assumed to be invariant under the pseudo C-symmetry. | [
"Physics Archive->hep->hep-ph",
"Physics Archive->hep->hep-th"
] | "2019-10-08T03:10:15Z" |
2104.06705 | A User's Guide to Morse Foliated Open Books | Morse foliated open books were introduced by the autors (along with abstract and embedded versions) as a tool for studying contact manifolds with boundary, and this article illustrates the advantages of the Morse perspective. We use this to extend the definition of \textit{right-veering} to foliated open books and we show that it plays a similar role in detecting overtwistedness as in other versions of open books. | [
"Mathematics Archive->math.GT",
"Mathematics Archive->math.SG"
] | "2021-04-14T08:52:37Z" |
2102.10982 | Efficient MPS methods for extracting spectral information on rings and cylinders | Based on the MPS formalism, we introduce an ansatz for capturing excited states in finite systems with open boundary conditions, providing a very efficient method for computing, e.g., the spectral gap of quantum spin chains. This method can be straightforwardly implemented on top of an existing DMRG or MPS ground-state code. Although this approach is built on open-boundary MPS, we also apply it to systems with periodic boundary conditions. Despite the explicit breaking of translation symmetry by the MPS representation, we show that momentum emerges as a good quantum number, and can be exploited for labeling excitations on top of MPS ground states. We apply our method to the critical Ising chain on a ring and the classical Potts model on a cylinder. Finally, we apply the same idea to compute excitation spectra for 2-D quantum systems on infinite cylinders. Again, despite the explicit breaking of translation symmetry in the periodic direction, we recover momentum as a good quantum number for labeling excitations. We apply this method to the 2-D transverse-field Ising model and the half-filled Hubbard model; for the latter, we obtain accurate results for, e.g., the hole dispersion for cylinder circumferences up to eight sites. | [
"Physics Archive->cond-mat->cond-mat.str-el",
"Physics Archive->quant-ph"
] | "2021-02-22T13:35:09Z" |
nlin/0011039 | On the relation between multifield and multidimensional integrable equations | The new examples are found of the constraints which link the 1+2-dimensional and multifield integrable equations and lattices. The vector and matrix generalizations of the Nonlinear Schr\"odinger equation and the Ablowitz-Ladik lattice are considered among the other multifield models. It is demonstrated that using of the symmetries belonging to the hierarchies of these equations leads, in particular, to the KP equation and twodimensional analogs of the dressing chain, Toda lattice and dispersive long waves equations. In these examples the multifield equation and its symmetry have meaning of the Lax pair for the corresponding twodimensional equation under some compatible constraint between field variables and eigenfunctions. | [
"Physics Archive->nlin->nlin.SI"
] | "2000-11-21T10:34:02Z" |
1910.00352 | Proximal Policy Optimization for Improved Convergence in IRGAN | IRGAN is an information retrieval (IR) modeling approach that uses a theoretical minimax game between a generative and a discriminative model to iteratively optimize both of them, hence unifying the generative and discriminative approaches. Despite significant performance improvements in several information retrieval tasks, IRGAN training is an unstable process, and the solution varies largely with the random parameter initialization. In this work, we present an improved training objective based on proximal policy optimization objective and Gumbel-Softmax based sampling for the generator. We also propose a modified training algorithm which takes a single gradient update on both the generator as well as discriminator for each iteration step. We present empirical evidence of the improved convergence of the proposed model over the original IRGAN and a comparison on three different IR tasks on benchmark datasets is also discussed, emphasizing the proposed model's superior performance. | [
"Computer Science Archive->cs.IR",
"Computer Science Archive->cs.LG"
] | "2019-10-01T12:56:32Z" |
1303.0014 | Complex geodesics in convex tube domains | We describe all complex geodesics in convex tube domains. In the case when the base of a convex tube domain does not contain any real line, the obtained description involves the notion of boundary measure of a holomorphic map and it is expressed in the language of real Borel measures on the unit circle. Applying our result, we calculate all complex geodesics in convex tube domains with unbounded base covering special class of Reinhardt domains. | [
"Mathematics Archive->math.CV"
] | "2013-02-28T21:06:25Z" |
gr-qc/0604104 | Ultrarelativistic sources in nonlinear electrodynamics | The fields of rapidly moving sources are studied within nonlinear electrodynamics by boosting the fields of sources at rest. As a consequence of the ultrarelativistic limit the delta-like electromagnetic shock waves are found. The character of the field within the shock depends on the theory of nonlinear electrodynamics considered. In particular, we obtain the field of an ultrarelativistic charge in the Born-Infeld theory. | [
"Physics Archive->gr-qc",
"Physics Archive->hep->hep-th"
] | "2006-04-22T19:03:14Z" |
2212.03430 | Early-type Dwarf Galaxies in the Local Universe. Evidence of Ex-situ Growth | We report the discovery of a rare early-type dwarf galaxy (dE), SDSS J125651.47+163024.2 (hereafter dE1256), possessing a tidal feature that was likely built up by accretion of an even smaller dwarf galaxy. dE1256 is located in a nearly isolated environment, at the outskirt of the Virgo cluster. A detailed morphological examination reveals that the accreted stellar population is mainly deposited in the outer part of dE1256, where the tidal tail is most prominent. The inner part of dE1256 is perfectly modeled with a simple S\'ersic function of index n = 0.63 and half-light radius R$_{h}$ = 0.6 kpc, but in contrast, the entire galaxy has a size of R$_{h}$ = 1.2 kpc. The mass ratio between the host and the putative accreted dwarf galaxy is calculated to be 5:1, assuming that the observed two components, inner S\'ersic, and outer tidal tail residual, represent the host's and accreted galaxy's stellar populations, respectively. We suggest that while the accretion contributes only 20% of the overall stellar population, the size of dE1256 grew by a factor of two via the accretion event. Our results provide, for the first time, strong observational evidence that a dE is undergoing a two-phase growth, a common phenomenon for massive galaxies. | [
"Physics Archive->astro-ph->astro-ph.GA"
] | "2022-12-07T03:31:57Z" |
quant-ph/0306027 | Beam Splitter Entangler for Light Fields | We propose an experimentally feasible scheme to generate various types of entangled states of light fields by using beam splitters and single-photon detectors. Two light fields are incident on two beam splitters and are split into strong and weak output modes respectively. A conditional joint measurement on both weak output modes may result in an entanglement between the two strong output modes. The conditions for the maximal entanglement are discussed based on the concurrence. Several specific examples are also examined. | [
"Physics Archive->quant-ph"
] | "2003-06-04T06:59:55Z" |
2003.09251 | Analysis of the SORAS domain decomposition preconditioner for non-self-adjoint or indefinite problems | We analyze the convergence of the one-level overlapping domain decomposition preconditioner SORAS (Symmetrized Optimized Restricted Additive Schwarz) applied to a generic linear system whose matrix is not necessarily symmetric/self-adjoint nor positive definite. By generalizing the theory for the Helmholtz equation developed in [I.G. Graham, E.A. Spence, and J. Zou, SIAM J.Numer.Anal., 2020], we identify a list of assumptions and estimates that are sufficient to obtain an upper bound on the norm of the preconditioned matrix, and a lower bound on the distance of its field of values from the origin. We stress that our theory is general in the sense that it is not specific to one particular boundary value problem. Moreover, it does not rely on a coarse mesh whose elements are sufficiently small. As an illustration of this framework, we prove new estimates for overlapping domain decomposition methods with Robin-type transmission conditions for the heterogeneous reaction-convection-diffusion equation (to prove the stability assumption for this equation we consider the case of a coercive bilinear form, which is non-symmetric, though). | [
"Computer Science Archive->cs.NA",
"Mathematics Archive->math.NA"
] | "2020-03-20T13:15:31Z" |
1703.03464 | Gravitational collapse of the OMC-1 region | We have investigated the global dynamical state of the Integral Shaped Filament in the Orion A cloud using new N$_2$H$^+$ (1-0) large-scale, IRAM30m observations. Our analysis of its internal gas dynamics reveals the presence of accelerated motions towards the Orion Nebula Cluster, showing a characteristic blue-shifted profile centred at the position of the OMC-1 South region. The properties of these observed gas motions (profile, extension, and magnitude) are consistent with the expected accelerations for the gravitational collapse of the OMC-1 region and explain both the physical and kinematic structure of this cloud. | [
"Physics Archive->astro-ph->astro-ph.GA",
"Physics Archive->astro-ph->astro-ph.SR"
] | "2017-03-09T21:04:26Z" |
2109.05791 | Unified Kinematic and Dynamical Modeling of a Soft Robotic Arm by a Piecewise Universal Joint Model | The compliance of soft robotic arms renders the development of accurate kinematic & dynamical models especially challenging. The most widely used model in soft robotic kinematics assumes Piecewise Constant Curvature (PCC). However, PCC fails to effectively handle external forces, or even the influence of gravity, since the robot does not deform with a constant curvature under these conditions. In this paper, we establish three-dimensional (3D) modeling of a multi-segment soft robotic arm under the less restrictive assumption that each segment of the arm is deformed on a plane without twisting. We devise a kinematic and dynamical model for the soft arm by deriving equivalence to a serial universal joint robot. Numerous experiments on the real robot platform along with simulations attest to the modeling accuracy of our approach in 3D motion with load. The maximum position/rotation error of the proposed model is verified 6.7x/4.6x lower than the PCC model considering gravity and external forces. | [
"Computer Science Archive->cs.RO"
] | "2021-09-13T09:13:33Z" |
1310.1979 | The SLUGGS Survey: The globular cluster systems of three early-type galaxies using wide-field imaging | We present the results from a wide-field imaging study of globular cluster (GC) systems in three early-type galaxies. Combinations of Subaru/Suprime-Cam, CFHT/MegaCam and HST/WFPC2/ACS data were used to determine the GC system properties of three highly flattened galaxies NGC 720, NGC 1023 and NGC 2768. This work is the first investigation of the GC system in NGC 720 and NGC 2768 to very large galactocentric radius ($\sim$ 100 kpc). The three galaxies have clear blue and red GC subpopulations. The radial surface densities of the GC systems are fitted with Sersic profiles, and detected out to 15, 8 and 10 galaxy effective radii respectively. The total number of GCs and specific frequency are determined for each GC system. The ellipticity of the red subpopulation is in better agreement with the host galaxy properties than is the blue subpopulation, supporting the traditional view that metal-rich GCs are closely associated with the bulk of their host galaxies' field stars, while metal-poor GCs reflect a distinct stellar halo. With the addition of another 37 literature studied galaxies, we present a new correlation of GC system extent with host galaxy effective radius. We find a dependence of the relative fraction of blue to red GCs with host galaxy environmental density for lenticular galaxies (but not for elliptical or spiral galaxies). We propose that tidal interactions between galaxies in cluster environments might be the reason behind the observed trend for lenticular galaxies. | [
"Physics Archive->astro-ph->astro-ph.CO"
] | "2013-10-08T01:34:05Z" |
2106.03501 | Set-Estimation based Networked Model Predictive Control for Energy Management of Faulty Microgrids | This paper addresses the issue of power flow control for partially faulty microgrids. In microgrid control systems, faults may occur in both electrical and communication layers. This may have severe effects on the operation of microgrids. In addition, disturbances always coexist with faults in microgrids, which may further deteriorate system performance. To address the faults and disturbances simultaneously, a model predictive control (MPC) method based on set-membership estimation (SME) that transmits information via a communication network is proposed. When electrical devices are nonfunctional or communication failures occur, the corresponding system states will become unavailable. To this end, the SME method is employed to estimate the states with the existence of unknown-but-bounded process and measurement disturbances. The networked MPC method is designed to schedule the power dispatch by using the forecasts of photovoltaic (PV) generation and load demand. With these two methods, the fault-tolerant control can be achieved. Further, a deviation compensation method is proposed to compensate for the forecast errors. The effectiveness of the proposed control strategy is demonstrated through wireless communication tests using Raspberry Pis. | [
"Computer Science Archive->cs.SY",
"Electrical Engineering and Systems Science Archive->eess.SY"
] | "2021-06-07T10:40:30Z" |
1805.09214 | A Unified Framework for Training Neural Networks | The lack of mathematical tractability of Deep Neural Networks (DNNs) has hindered progress towards having a unified convergence analysis of training algorithms, in the general setting. We propose a unified optimization framework for training different types of DNNs, and establish its convergence for arbitrary loss, activation, and regularization functions, assumed to be smooth. We show that framework generalizes well-known first- and second-order training methods, and thus allows us to show the convergence of these methods for various DNN architectures and learning tasks, as a special case of our approach. We discuss some of its applications in training various DNN architectures (e.g., feed-forward, convolutional, linear networks), to regression and classification tasks. | [
"Computer Science Archive->cs.LG",
"Statistics Archive->stat.ML"
] | "2018-05-23T15:13:56Z" |
hep-ph/0407090 | Single Field Baryogenesis | We propose a new variant of the Affleck-Dine baryogenesis mechanism in which a rolling scalar field couples directly to left- and right-handed neutrinos, generating a Dirac mass term through neutrino Yukawa interactions. In this setup, there are no explicitly CP violating couplings in the Lagrangian. The rolling scalar field is also taken to be uncharged under the $B - L$ quantum numbers. During the phase of rolling, scalar field decays generate a non-vanishing number density of left-handed neutrinos, which then induce a net baryon number density via electroweak sphaleron transitions. | [
"Physics Archive->astro-ph",
"Physics Archive->gr-qc",
"Physics Archive->hep->hep-ph",
"Physics Archive->hep->hep-th"
] | "2004-07-07T16:04:39Z" |
math/0303121 | Invariant sets and measures of nonexpansive group automorphisms | We prove that the restriction of a probability measure invariant under a nonhyperbolic, ergodic and totally irreducible automorphism of a compact connected abelian group to the leaves of the central foliation is severely restricted. We also prove a topological analogue of this result: the intersection of every proper closed invariant subset with each central leaf is compact. | [
"Mathematics Archive->math.DS"
] | "2003-03-11T00:45:54Z" |
2001.06251 | Active reset of a radiative cascade for superequilibrium entangled photon generation | The generation rate of entangled photons emitted from cascaded few-level systems is intrinsically limited by the lifetime of the radiative transitions. Here, we overcome this limit for entangled photon pairs from quantum dots via a novel driving regime based on an active reset of the radiative cascade. We show theoretically and experimentally the driving regime to enable the generation of entangled photon pairs with higher fidelity and intensity compared to the optimum continuously driven equilibrium state. Finally, we electrically generate entangled photon pairs with a total fidelity of $(79.5 \pm 1.1)\%$ at a record clock rate of 1.15GHz. | [
"Physics Archive->cond-mat->cond-mat.mes-hall",
"Physics Archive->quant-ph"
] | "2020-01-17T11:51:33Z" |
0801.1427 | Effect of the surface-stimulated mode on the kinetics of homogeneous crystal nucleation in droplets | A kinetic theory of homogeneous crystal nucleation in unary droplets is presented taking into account that a crystal nucleus can form not only in the volume-based mode (with all its facets within the droplet) but also in the surface-stimulated one (with one of its facets at the droplet surface). The previously developed thermodynamics of surface-stimulated crystal nucleation rigorously showed that if at least one of the facets of the crystal is only partially wettable by its melt, then it is thermodynamically more favorable for the nucleus to form with that facet at the droplet surface rather than within the droplet. So far, however, the kinetic aspects of this phenomenon had not been studied at all. The theory proposed in the present paper advocates that even in the surface-stimulated mode crystal nuclei initially emerge (as sub-critical clusters) homogeneously in the sub-surface layer, not "pseudo-heterogeneously" at the surface. A homogeneously emerged sub-critical crystal can become a surface-stimulated nucleus due to density and structure fluctuations. This effect contributes to the total rate of crystal nucleation (as the volume-based mode does). An explicit expression for the total per-particle rate of crystal nucleation is derived. Numerical evaluations for water droplets suggest that the surface-stimulated mode can significantly enhance the per-particle rate of crystal nucleation in droplets as large as 10 microns in radius. Possible experimental verification of the proposed theory is discussed. | [
"Physics Archive->cond-mat->cond-mat.mtrl-sci",
"Physics Archive->cond-mat->cond-mat.stat-mech"
] | "2008-01-09T13:49:24Z" |
0903.1889 | Test of Universal Rise of Hadronic Total Cross Sections based on pi p, Kp and pbar p,pp Scatterings | Recently there are several evidences of the hadronic total cross section sigma(tot) to be proportional to B (log s)2 consistent with the Froissart unitarity bound. The COMPETE collaborations have further assumed sigma(tot) = B (log s/s0)2 + Z to extend its universal rise with the common value of B and s0 for all hadronic scatterings to reduce the number of adjustable parameters. The coefficient B was suggested to be universal in the arguments of colour glass condensate (CGC) of QCD in recent years. There has been, however, no rigorous proof yet based only on QCD. We attempt to investigate the value of B for pi+- p, K+- p and pbar p,pp scatterings respectively through the search for the simultaneous best fit to the experimental sigma(tot) and rho ratios at high energies. The sigma(tot) at the resonance and intermediate energy regions has also been exploited as a duality constraint based on the special form of finite-energy sum rule(FESR). We estimate the values of B, s0 and Z individually for pi+- p, K+- p and pbar p,pp scatterings without using the universality hypothesis. It turs out that the values of B are mutually consistent within one standard deviation. It has to be stressed that we cannot obtain such a definite conclusion without the duality constraint. It is also interesting to note that the values of Z for pi p, Kp and pbar(p)p approximately satisfy the ratio 2:2:3 predicted by the quark model. The obtained value of B for pbar(p)p is Bpp = 0.280 +- 0.015 mb, which predicts sigma(tot)(pp) =108.0 +- 1.9mb and rho(pp) =0.131+- 0.0025 at the LHC energy s^0.5 =14 TeV. | [
"Physics Archive->hep->hep-ph"
] | "2009-03-11T02:03:11Z" |
1104.3431 | Local Semicircle law and Gaussian fluctuation for Hermite $\beta$ ensemble | Let $\beta>0$ and consider an $n$-point process $\lambda_1, \lambda_2,..., \lambda_n$ from Hermite $\beta$ ensemble on the real line $\mathbb{R}$. Dumitriu and Edelman discovered a tri-diagonal matrix model and established the global Wigner semicircle law for normalized empirical measures. In this paper we prove that the average number of states in a small interval in the bulk converges in probability when the length of the interval is larger than $\sqrt {\log n}$, i.e., local semicircle law holds. And the number of positive states in $(0,\infty)$ is proved to fluctuate normally around its mean $n/2$ with variance like $\log n/\pi^2\beta$. The proofs rely largely on the way invented by Valk$\acute{o}$ and Vir$\acute{a}$g of counting states in any interval and the classical martingale argument. | [
"Mathematics Archive->math.MP",
"Mathematics Archive->math.PR",
"Physics Archive->math-ph"
] | "2011-04-18T11:01:41Z" |
0810.0201 | A Metal-biased Planet Search | We have begun a metal-rich planet search project using the HARPS instrument in La Silla, Chile to target planets with a high potential to transit their host star and add to the number of bright benchmark transiting planets. The sample currently consists of 100, bright (7.5 </= V </= 9.5) solar-type stars (0.5 </= B-V </= 0.9) in the southern hemisphere which are both inactive (logR'HK </= -4.5) and metal-rich ([Fe/H] >/= 0.1 dex). We determined the chromospheric activity and metallicity status of our sample using high resolution FEROS spectra. We also introduce the first result from our HARPS planet search and show that the radial-velocity amplitude of this star is consistent with an orbiting planetary-mass companion (i.e. Msini < 0.5MJ) with a period of ~5 days. We are currently engaged in follow-up to confirm this signal as a bonafide orbiting planet. | [
"Physics Archive->astro-ph"
] | "2008-10-01T16:03:31Z" |
1209.0405 | Time-Optimal Transfer of Coherence | We provide exact analytical solutions for the problem of time-optimal transfer of coherence from one spin polarization to a three-fold coherence in a trilinear Ising chain with a fixed energy available and subject to local controls with a non negligible time cost. The time of transfer is optimal and consistent with a previous numerical result obtained assuming instantaneous local controls. | [
"Physics Archive->quant-ph"
] | "2012-09-03T16:49:13Z" |
1506.07702 | Metallic multilayers for X-band Bragg reflector applications | We present a structural and high frequency (8.72GHz) electrical characterization of sputter deposited Ti/W, Ti/Ru and Mo/Ti metallic multilayers for potential application as acoustic Bragg reflectors. We prove that all metallic multilayers comprised of different acoustic impedance metals such as Ti, W, Mo are promising candidates for Bragg reflector/bottom electrode in full X-band thin film acoustic resonators. Values for high frequency resistivity of the order of $10^{-8} ohm.m$ are measured by use of a contact-free/non-invasive sheet resistance method. | [
"Physics Archive->cond-mat->cond-mat.mtrl-sci"
] | "2015-06-25T11:04:54Z" |
nlin/0001014 | Asymmetric Squares as Standing Waves in Rayleigh-Benard Convection | Possibility of asymmetric square convection is investigated numerically using a few mode Lorenz-like model for thermal convection in Boussinesq fluids confined between two stress free and conducting flat boundaries. For relatively large value of Rayleigh number, the stationary rolls become unstable and asymmetric squares appear as standing waves at the onset of secondary instability. Asymmetric squares, two dimensional rolls and again asymmetric squares with their corners shifted by half a wavelength form a stable limit cycle. | [
"Physics Archive->nlin->nlin.PS"
] | "2000-01-11T13:33:09Z" |
cond-mat/0506601 | Quantum transitions induced by the third cumulant of current fluctuations | We investigate the transitions induced by external current fluctuations on a small probe quantum system. The rates for the transitions between the energy states are calculated using the real-time Keldysh formalism for the density matrix evolution. We especially detail the effects of the third cumulant of current fluctuations inductively coupled to a quantum bit and propose a setup for detecting the frequency-dependent third cumulant through the transitions it induces. | [
"Physics Archive->cond-mat->cond-mat.mes-hall",
"Physics Archive->cond-mat->cond-mat.supr-con"
] | "2005-06-23T13:18:31Z" |
quant-ph/0003122 | Quantum Computation with hot and cold ions:An assessment of proposed schemes | We present a brief critical review of the proposals for quantum computation with trapped ions, with particular emphasis on the possibilities for quantum computation without the need for cooling to the quantum ground state of the ions' collective oscillatory modes. | [
"Physics Archive->quant-ph"
] | "2000-03-27T16:09:10Z" |
1402.4816 | IGM Emission Observations with the Cosmic Web Imager: I. The Circum-QSO Medium of QSO 1549+19, and Evidence for a Filamentary Gas Inflow | The Palomar Cosmic Web Imager (PCWI), an integral field spectrograph designed to detect and map low surface brightness emission, has obtained imaging spectroscopic maps of Ly-alpha from the circum-QSO medium (CQM) of QSO HS1549+19 at redshift of 2.843. Extensive extended emission is detected from the CQM, consistent with fluorescent and pumped Ly-alpha produced by the ionizing and Ly-alpha continuum of the QSO. Many features present in PCWI spectral images match those detected in narrow-band images. Filamentary structures with narrow line profiles are detected in several cases as long as 250-400 kpc. One of these is centered at a velocity redshifted with respect to the systemic velocity, and displays a spatially collimated and kinematically cold line profile increasing in velocity width approaching the QSO. This suggests that the filament gas is infalling onto the QSO, perhaps in a cold accretion flow. Because of the strong ionizing flux, the neutral column density is low, typically N(HI) is roughly 10E12-10E15/square-cm, and the line center optical depth is also low (typically tau0 is less than 10), insufficient to display well-separated double peak emission characteristic of higher line optical depths. With a simple ionization and cloud model we can very roughly estimate the total gas mass (log M(gas) equal to 12.5 +/- 0.5) and the total mass (log M(tot) equal to 13.3+/- 0.5). We can also calculate a kinematic mass from the total line profile (2x10E13 M(sun)), which agrees with the mass estimated from the gas emission. The intensity-binned spectrum of the CQM shows a progression in kinematic properties consistent with heirarchical structure formation. | [
"Physics Archive->astro-ph->astro-ph.GA"
] | "2014-02-19T21:00:24Z" |
1103.3666 | Are magnetite (Fe3O4) films on MgAl2O4 auxetic? | Magnetite (Fe3O4) films were fabricated on MgAl2O4 (001) single crystal substrates by pulsed laser deposition. In-plane and out-of-plane lattice constants were determined by X-ray diffraction. The apparent Poisson's ratio was determined as the negative ratio of the out-of-plane to in-plane strains. The results show that (i) the determination of Poisson's ratio by this method is only reliable for fully strained films and (ii) Poisson's ratio = 0.3 along the <100> direction is positive for this archetypal ferrite. Fe3O4 films grown on MgAl2O4 (001) are not auxetic. | [
"Physics Archive->cond-mat->cond-mat.mtrl-sci"
] | "2011-03-18T17:09:15Z" |
0707.0592 | Triangles with two given integral sides | We study some Diophantine problems related to triangles with two given integral sides. We solve two problems posed by Zolt\'an Bertalan and we also provide some generalization. | [
"Mathematics Archive->math.NT"
] | "2007-07-04T12:30:01Z" |
1307.3260 | Strong Hyperfine-Induced Modulation of an Optically-Driven Hole Spin in an InAs Quantum Dot | Compared to electrons, holes in InAs quantum dots have a significantly weaker hyperfine interaction that leads to less dephasing from nuclear spins. Thus many recent studies have suggested that nuclear spins are unimportant for hole spin dynamics compared to electric field fluctuations. We show that the hole hyperfine interaction can have a strong effect on hole spin coherence measurements through a nuclear feedback effect. The nuclear polarization is generated through a unique process that is dependent on the anisotropy of the hole hyperfine interaction and the coherent precession of nuclear spins, giving rise to strong modulation at the nuclear precession frequency. | [
"Physics Archive->cond-mat->cond-mat.mes-hall",
"Physics Archive->quant-ph"
] | "2013-07-11T20:15:08Z" |
1311.1752 | Multilevel Monte Carlo for Random Degenerate Scalar Convection Diffusion Equation | We consider the numerical solution of scalar, nonlinear degenerate convection-diffusion problems with random diffusion coefficient and with random flux functions. Building on recent results on the existence, uniqueness and continuous dependence of weak solutions on data in the deterministic case, we develop a definition of random entropy solution. We establish existence, uniqueness, measurability and integrability results for these random entropy solutions, generalizing \cite{Mishr478,MishSch10a} to possibly degenerate hyperbolic-parabolic problems with random data. We next address the numerical approximation of random entropy solutions, specifically the approximation of the deterministic first and second order statistics. To this end, we consider explicit and implicit time discretization and Finite Difference methods in space, and single as well as Multi-Level Monte-Carlo methods to sample the statistics. We establish convergence rate estimates with respect to the discretization parameters, as well as with respect to the overall work, indicating substantial gains in efficiency are afforded under realistic regularity assumptions by the use of the Multi-Level Monte-Carlo method. Numerical experiments are presented which confirm the theoretical convergence estimates. | [
"Mathematics Archive->math.AP"
] | "2013-11-07T17:18:03Z" |
1312.1985 | A unique radioisotopic label as a new concept for safeguarding and tagging of long-term stored items and waste | The present paper discuss a novel method of tagging and labeling of waste casks, copper canisters, spent fuel containers, mercury containers, waste pack- ages and other items. In particular, it is related to the development of new long-term security identification tags/labels that can be applied to articles for carrying information about the content, inventory tracking, prevention of falsifi- cation and theft etc. It is suggested to use a unique combination of radioisotopes with different predictable length of life, as a label of the items. The possibil- ity to realize a multidimensional bar code symbology is proposed as an option for a new labeling method. The results of the first tests and evaluations of this are shown and discussed in the paper. The invention is suitable for use in items assigned to long-term (hundreds of years) storing or for final repositories. Alternative field of use includes fresh nuclear fuel handling and shipment of goods. | [
"Physics Archive->nucl->nucl-ex",
"Physics Archive->physics->physics.ins-det"
] | "2013-12-06T20:02:53Z" |
1712.09945 | Inverse Boundary Value Problem for Non-linear Hyperbolic Partial Differential Equations | In this article we are concerned with an inverse boundary value problem for a non-linear wave equation of divergence form with space dimension $n\geq 3$. In particular the so called the interior determination problem. This non-linear wave equation has a trivial solution, i.e. zero solution. By linearizing this equation at the trivial solution, we have the usual linear isotropic wave equation with the speed $\sqrt{\gamma(x)}$ at each point $x$ in a given spacial domain. For any small solution $u=u(t,x)$ of this non-linear equation, we have the linear isotropic wave equation perturbed by a divergence with respect to $x$ of a vector whose components are quadratics with respect to $\nabla_x u(t,x)$ by ignoring the terms with smallness $O(|\nabla_x u(t,x)|^3)$. We will show that we can uniquely determine $\gamma(x)$ and the coefficients of these quadratics by many boundary measurements at the boundary of the spacial domain over finite time interval. More precisely the boundary measurements are given as the so-called the hyperbolic Dirichlet to Neumann map. | [
"Mathematics Archive->math.AP"
] | "2017-12-28T17:27:46Z" |
2011.13932 | AdS$_2$ duals to ADHM quivers with Wilson lines | We discuss AdS$_2\times S^3\times{\text{CY}}_2\times I_{\rho}$ solutions to massive Type IIA supergravity with 4 Poincar\'e supersymmetries. We propose explicit dual quiver quantum mechanics built out of D0 and D4 colour branes coupled to D4' and D8 flavour branes. We propose that these quivers describe the interactions of instantons and Wilson lines in 5d gauge theories with 8 Poincar\'e supersymmetries. Using the RR Maxwell fluxes of the solutions, conveniently put off-shell, we construct a functional from which the holographic central charge can be derived through a geometrical extremisation principle | [
"Physics Archive->hep->hep-th"
] | "2020-11-27T19:00:00Z" |
1004.5184 | Reference frames for Bell inequality violation in the presence of superselection rules | Superselection rules (SSRs) constrain the allowed states and operations in quantum theory. They limit preparations and measurements hence impact upon our ability to observe non-locality, in particular the violation of Bell inequalities. We show that a reference frame compatible with a particle number SSR does not allow observers to violate a Bell inequality if and only if it is prepared using only local operations and classical communication. In particular, jointly prepared separable reference frames are sufficient for obtaining violations of a Bell inequality. We study the size and non-local properties of such reference frames using superselection-induced variance. These results suggest the need for experimental Bell tests in the presence of superselection. | [
"Physics Archive->quant-ph"
] | "2010-04-29T05:27:26Z" |
2312.07727 | Two-sample inference for sparse functional data | We propose a novel test procedure for comparing mean functions across two groups within the reproducing kernel Hilbert space (RKHS) framework. Our proposed method is adept at handling sparsely and irregularly sampled functional data when observation times are random for each subject. Conventional approaches, that are built upon functional principal components analysis, usually assume homogeneous covariance structure across groups. Nonetheless, justifying this assumption in real-world scenarios can be challenging. To eliminate the need for a homogeneous covariance structure, we first develop the functional Bahadur representation for the mean estimator under the RKHS framework; this representation naturally leads to the desirable pointwise limiting distributions. Moreover, we establish weak convergence for the mean estimator, allowing us to construct a test statistic for the mean difference. Our method is easily implementable and outperforms some conventional tests in controlling type I errors across various settings. We demonstrate the finite sample performance of our approach through extensive simulations and two real-world applications. | [
"Mathematics Archive->math.ST",
"Statistics Archive->stat.ME",
"Statistics Archive->stat.TH"
] | "2023-12-12T20:44:07Z" |
2006.01457 | Heat Diffusion in high-$C_p$ Nb$_3$Sn Composite Superconducting Wires | A major focus of Nb$_3$Sn accelerator magnets is on significantly reducing or eliminating their training. Demonstration of an approach to increase the $C_p$ of Nb$_3$Sn magnets using new materials and technologies is very important both for particle accelerators and light sources. It would improve thermal stability and lead to much shorter magnet training, with substantial savings in machines' commissioning costs. Both Hypertech and Bruker-OST have attempted to introduce high-$C_p$ elements in their wire design. This paper includes a description of these advanced wires, the finite element model of their heat diffusion properties as compared with the standard wires, and whenever available, a comparison between the minimum quench energy (MQE) calculated by the model and actual MQE measurements on wires. | [
"Physics Archive->physics->physics.acc-ph"
] | "2020-06-02T08:56:43Z" |
cond-mat/0108041 | Interacting Bose Gas in an Optical Lattice | A grand canonical system of hard-core bosons in an optical lattice is considered. The bosons can occupy randomly $N$ equivalent states at each lattice site. The limit $N\to\infty$ is solved exactly in terms of a saddle-point integration, representing a weakly-interacting Bose gas. At T=0 there is only a condensate in the limit $N\to\infty$. Corrections in 1/N increase the total density of bosons but suppress the condensate. This indicates a depletion of the condensate due to increasing interaction at finite values of N. | [
"Physics Archive->cond-mat->cond-mat.stat-mech"
] | "2001-08-02T14:06:11Z" |
1602.00798 | A Unified Framework for Information Consumption Based on Markov Chains | This paper establishes a Markov chain model as a unified framework for understanding information consumption processes in complex networks, with clear implications to the Internet and big-data technologies. In particular, the proposed model is the first one to address the formation mechanism of the "trichotomy" in observed probability density functions from empirical data of various social and technical networks. Both simulation and experimental results demonstrate a good match of the proposed model with real datasets, showing its superiority over the classical power-law models. | [
"Computer Science Archive->cs.SI",
"Physics Archive->physics->physics.soc-ph"
] | "2016-02-02T05:54:24Z" |
1701.00638 | Confluence of Conditional Term Rewrite Systems via Transformations | Conditional term rewriting is an intuitive yet complex extension of term rewriting. In order to benefit from the simpler framework of unconditional rewriting, transformations have been defined to eliminate the conditions of conditional term rewrite systems. Recent results provide confluence criteria for conditional term rewrite systems via transformations, yet they are restricted to CTRSs with certain syntactic properties like weak left-linearity. These syntactic properties imply that the transformations are sound for the given CTRS. This paper shows how to use transformations to prove confluence of operationally terminating, right-stable deterministic conditional term rewrite systems without the necessity of soundness restrictions. For this purpose, it is shown that certain rewrite strategies, in particular almost U-eagerness and innermost rewriting, always imply soundness. | [
"Computer Science Archive->cs.LO"
] | "2017-01-03T10:38:23Z" |
1402.1225 | Comment on "Epidemiological modeling of online social network dynamics" | In this comment we give a simple analytic approximate solution to the infectious recovery SIR (irSIR) model given by J. Cannarella and J. A. Spechler arXiv:1401.4208, which is a variant of the traditional SIR model. | [
"Physics Archive->physics->physics.soc-ph"
] | "2014-02-06T01:41:37Z" |
2106.09672 | The 2021 Image Similarity Dataset and Challenge | This paper introduces a new benchmark for large-scale image similarity detection. This benchmark is used for the Image Similarity Challenge at NeurIPS'21 (ISC2021). The goal is to determine whether a query image is a modified copy of any image in a reference corpus of size 1~million. The benchmark features a variety of image transformations such as automated transformations, hand-crafted image edits and machine-learning based manipulations. This mimics real-life cases appearing in social media, for example for integrity-related problems dealing with misinformation and objectionable content. The strength of the image manipulations, and therefore the difficulty of the benchmark, is calibrated according to the performance of a set of baseline approaches. Both the query and reference set contain a majority of "distractor" images that do not match, which corresponds to a real-life needle-in-haystack setting, and the evaluation metric reflects that. We expect the DISC21 benchmark to promote image copy detection as an important and challenging computer vision task and refresh the state of the art. Code and data are available at https://github.com/facebookresearch/isc2021 | [
"Computer Science Archive->cs.CV"
] | "2021-06-17T17:23:59Z" |
1904.04452 | SPM-Tracker: Series-Parallel Matching for Real-Time Visual Object Tracking | The greatest challenge facing visual object tracking is the simultaneous requirements on robustness and discrimination power. In this paper, we propose a SiamFC-based tracker, named SPM-Tracker, to tackle this challenge. The basic idea is to address the two requirements in two separate matching stages. Robustness is strengthened in the coarse matching (CM) stage through generalized training while discrimination power is enhanced in the fine matching (FM) stage through a distance learning network. The two stages are connected in series as the input proposals of the FM stage are generated by the CM stage. They are also connected in parallel as the matching scores and box location refinements are fused to generate the final results. This innovative series-parallel structure takes advantage of both stages and results in superior performance. The proposed SPM-Tracker, running at 120fps on GPU, achieves an AUC of 0.687 on OTB-100 and an EAO of 0.434 on VOT-16, exceeding other real-time trackers by a notable margin. | [
"Computer Science Archive->cs.CV"
] | "2019-04-09T03:36:47Z" |
1510.01926 | Projective Limits of State Spaces IV. Fractal Label Sets | Instead of formulating the state space of a quantum field theory over one big Hilbert space, it has been proposed by Kijowski [Kijowski 1977] to represent quantum states as projective families of density matrices over a collection of smaller, simpler Hilbert spaces. One can thus bypass the need to select a vacuum state for the theory, and still be provided with an explicit and constructive description of the quantum state space, at least as long as the label set indexing the projective structure is countable. Because uncountable label sets are much less practical in this context, we develop in the present article a general procedure to trim an originally uncountable label set down to countable cardinality. In particular, we investigate how to perform this tightening of the label set in a way that preserves both the physical content of the algebra of observables and its symmetries. This work is notably motivated by applications to the holonomy-flux algebra underlying Loop Quantum Gravity. Building on earlier work by Okolow [arXiv:1304.6330], a projective state space was introduced for this algebra in [arXiv:1411.3592]. However, the non-trivial structure of the holonomy-flux algebra prevents the construction of satisfactory semi-classical states. Implementing the general procedure just mentioned in the case of a one-dimensional version of this algebra, we show how a discrete subalgebra can be extracted without destroying universality nor diffeomorphism invariance. On this subalgebra, states can then be constructed whose semi-classicality is enforced step by step, starting from collective, macroscopic degrees of freedom and going down progressively toward smaller and smaller scales. | [
"Mathematics Archive->math.MP",
"Physics Archive->gr-qc",
"Physics Archive->hep->hep-th",
"Physics Archive->math-ph"
] | "2015-10-07T12:51:38Z" |
hep-ex/0302032 | Physics of the CLAS collaboration: some selected results | The CLAS collaboration in Hall B at the Thomas Jeffeson National Accelerator Facility (Jefferson Lab) has a broad scientific program. Recent results on the main topics are presented. These concern the electromagnetic exitation of nucleon resonances, the measurement of inclusive spin structrure functions in the nucleon resonance region, the first signature of the Generalized Parton Distributions through the Deeply Virtual Compton Scattering measurement and the deuteron photodisintegration and photoproduction of light vector mesons. | [
"Physics Archive->hep->hep-ex"
] | "2003-02-23T23:32:11Z" |
cond-mat/0311437 | Exact pairing correlations in one-dimensional trapped fermions with stochastic mean-field wave-functions | The canonical thermodynamic properties of a one-dimensional system of interacting spin-1/2 fermions with an attractive zero-range pseudo-potential are investigated within an exact approach. The density operator is evaluated as the statistical average of dyadics formed from a stochastic mean-field propagation of independent Slater determinants. For an harmonically trapped Fermi gas and for fermions confined in a 1D-like torus, we observe the transition to a quasi-BCS state with Cooper-like momentum correlations and an algebraic long-range order. For few trapped fermions in a rotating torus, a dominant superfluid component with quantized circulation can be isolated. | [
"Physics Archive->cond-mat->cond-mat.stat-mech"
] | "2003-11-19T10:58:29Z" |
2202.05827 | Automated Architecture Search for Brain-inspired Hyperdimensional Computing | This paper represents the first effort to explore an automated architecture search for hyperdimensional computing (HDC), a type of brain-inspired neural network. Currently, HDC design is largely carried out in an application-specific ad-hoc manner, which significantly limits its application. Furthermore, the approach leads to inferior accuracy and efficiency, which suggests that HDC cannot perform competitively against deep neural networks. Herein, we present a thorough study to formulate an HDC architecture search space. On top of the search space, we apply reinforcement-learning to automatically explore the HDC architectures. The searched HDC architectures show competitive performance on case studies involving a drug discovery dataset and a language recognition task. On the Clintox dataset, which tries to learn features from developed drugs that passed/failed clinical trials for toxicity reasons, the searched HDC architecture obtains the state-of-the-art ROC-AUC scores, which are 0.80% higher than the manually designed HDC and 9.75% higher than conventional neural networks. Similar results are achieved on the language recognition task, with 1.27% higher performance than conventional methods. | [
"Computer Science Archive->cs.LG"
] | "2022-02-11T18:43:36Z" |
cs/0411081 | Reconfigurations dynamiques de services dans un intergiciel a composants CORBA CCM | Today, component oriented middlewares are used to design, develop and deploy easily distributed applications, by ensuring the heterogeneity, interoperability, and reuse of the software modules, and the separation between the business code encapsulated in the components and the system code managed by the containers. Several standards answer this definition such as: CCM (CORBA Component Model), EJB (Enterprise Java Beans) and .Net. However these standards offer a limited and fixed number of system services, removing any possibility to add system services or to reconfigure dynamically the middleware. Our works propose mechanisms to add and to adapt dynamically the system services, based on a reconfiguration language which is dynamically adaptable to the need of the reconfiguration, and on a tool of dynamic reconfiguration, a prototype was achieved for the OpenCCM platform, that is an implementation of the CCM specification. This work was partially financed by the european project IST-COACH (2001-34445). | [
"Computer Science Archive->cs.NI"
] | "2004-11-24T10:26:10Z" |
2306.11707 | Hexagonal circular 3-webs with polar curves of degree three | The paper reports the progress with the classical problem, posed by Blaschke and Bol in 1938. We present new examples and new classifications of natural classes of hexagonal circular 3-webs. The main results is the classification of hexagonal circular 3-webs with polar curves of degree 3. | [
"Mathematics Archive->math.DG"
] | "2023-06-20T17:36:40Z" |
2005.05127 | Asymptotic Reduction of a Lithium-ion Pouch Cell Model | A three-dimensional model of a single-layer lithium-ion pouch cell is presented which couples conventional porous electrode theory describing cell electrochemical behaviour with an energy balance describing cell thermal behaviour. Asymptotic analysis of the model is carried out by exploiting the small aspect ratio typical of pouch cell designs. The analysis reveals the scaling that results in a distinguished limit, and highlights the role played by the electrical conductivities of the current collectors. The resulting model comprises a collection of one-dimensional models for the through-cell electrochemical behaviour which are coupled via two-dimensional problems for the Ohmic and thermal behaviour in the planar current collectors. A further limit is identified which reduces the problem to a single volume-averaged through-cell model, greatly reducing the computational complexity. Numerical simulations are presented which illustrate and validate the asymptotic results. | [
"Physics Archive->physics->physics.app-ph"
] | "2020-05-11T14:11:56Z" |
1904.11382 | Dual-Arm In-Hand Manipulation and Regrasping Using Dexterous Manipulation Graphs | This work focuses on the problem of in-hand manipulation and regrasping of objects with parallel grippers. We propose Dexterous Manipulation Graph (DMG) as a representation on which we define planning for in-hand manipulation and regrasping. The DMG is a disconnected undirected graph that represents the possible motions of a finger along the object's surface. We formulate the in-hand manipulation and regrasping problem as a graph search problem from the initial to the final configuration. The resulting plan is a sequence of coordinated in-hand pushing and regrasping movements. We propose a dual-arm system for the execution of the sequence where both hands are used interchangeably. We demonstrate our approach on an ABB Yumi robot tasked with different grasp reconfigurations. | [
"Computer Science Archive->cs.RO"
] | "2019-04-25T14:35:54Z" |
2108.01363 | Extracting the parton distribution functions evolution equations using the stochastic modeling in the non-equilibrium statistical mechanics | In this paper, using the stochastic modeling of the non-equilibrium statistical mechanics in the momentum space, the evolution equations of the parton distribution functions (PDF) usually used in the hadrons phenomenology are generated. These stochastic modeling PDF evolution equations are the same as those of the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) ones, but they can be obtained by a more simplistic mathematical procedure based on the non-equilibrium statistical mechanics and the theory of Markov processes. | [
"Physics Archive->hep->hep-ex",
"Physics Archive->hep->hep-ph"
] | "2021-08-03T08:41:32Z" |
2204.07710 | Accelerated Magnonic Motional Cooling with Deep Reinforcement Learning | Achieving fast cooling of motional modes is a prerequisite for leveraging such bosonic quanta for high-speed quantum information processing. In this work, we address the aspect of reducing the time limit for cooling below that constrained by the conventional sideband cooling techniques; and propose a scheme to apply deep reinforcement learning (DRL) to achieve this. In particular, we have shown how the scheme can be used effectively to accelerate the dynamic motional cooling of a macroscopic magnonic sphere, and how it can be uniformly extended for more complex systems, for example, a tripartite opto-magno-mechanical system to obtain cooling of the motional mode below the time bound of coherent cooling. While conventional sideband cooling methods do not work beyond the well-known rotating wave approximation (RWA) regimes, our proposed DRL scheme can be applied uniformly to regimes operating within and beyond the RWA, and thus this offers a new and complete toolkit for rapid control and generation of macroscopic quantum states for application in quantum technologies. | [
"Physics Archive->quant-ph"
] | "2022-04-16T03:52:43Z" |
1204.1162 | Performance of the Google Desktop, Arabic Google Desktop and Peer to Peer Application in Arabic Language | The Arabic language is a complex language; it is different from Western languages especially at the morphological and spelling variations. Indeed, the performance of information retrieval systems in the Arabic language is still a problem. For this reason, we are interested in studying the performance of the most famous search engine, which is a Google Desktop, while searching in Arabic language documents. Then, we propose an update to the Google Desktop to take into consideration in search the Arabic words that have the same root. After that, we evaluate the performance of the Google Desktop in this context. Also, we are interested in evaluation the performance of peer-to-peer application in two ways. The first one uses a simple indexation that indexes Arabic documents without taking in consideration the root of words. The second way takes in consideration the roots in the indexation of Arabic documents. This evaluation is done by using a corpus of ten thousand documents and one hundred different queries. | [
"Computer Science Archive->cs.IR"
] | "2012-04-05T09:38:23Z" |
2111.07722 | Stacked BNAS: Rethinking Broad Convolutional Neural Network for Neural Architecture Search | Different from other deep scalable architecture-based NAS approaches, Broad Neural Architecture Search (BNAS) proposes a broad scalable architecture which consists of convolution and enhancement blocks, dubbed Broad Convolutional Neural Network (BCNN), as the search space for amazing efficiency improvement. BCNN reuses the topologies of cells in the convolution block so that BNAS can employ few cells for efficient search. Moreover, multi-scale feature fusion and knowledge embedding are proposed to improve the performance of BCNN with shallow topology. However, BNAS suffers some drawbacks: 1) insufficient representation diversity for feature fusion and enhancement and 2) time consumption of knowledge embedding design by human experts. This paper proposes Stacked BNAS, whose search space is a developed broad scalable architecture named Stacked BCNN, with better performance than BNAS. On the one hand, Stacked BCNN treats mini BCNN as a basic block to preserve comprehensive representation and deliver powerful feature extraction ability. For multi-scale feature enhancement, each mini BCNN feeds the outputs of deep and broad cells to the enhancement cell. For multi-scale feature fusion, each mini BCNN feeds the outputs of deep, broad and enhancement cells to the output node. On the other hand, Knowledge Embedding Search (KES) is proposed to learn appropriate knowledge embeddings in a differentiable way. Moreover, the basic unit of KES is an over-parameterized knowledge embedding module that consists of all possible candidate knowledge embeddings. Experimental results show that 1) Stacked BNAS obtains better performance than BNAS-v2 on both CIFAR-10 and ImageNet, 2) the proposed KES algorithm contributes to reducing the parameters of the learned architecture with satisfactory performance, and 3) Stacked BNAS delivers a state-of-the-art efficiency of 0.02 GPU days. | [
"Computer Science Archive->cs.CV"
] | "2021-11-15T12:49:27Z" |
1508.02161 | Random data Cauchy problem for the nonlinear Schr\"{o}dinger equation with derivative nonlinearity | We consider the Cauchy problem for the nonlinear Schr\"{o}dinger equation with derivative nonlinearity $(i\partial _t + \Delta ) u= \pm \partial (\overline{u}^m)$ on $\R ^d$, $d \ge 1$, with random initial data, where $\partial$ is a first order derivative with respect to the spatial variable, for example a linear combination of $\frac{\partial}{\partial x_1} , \, \dots , \, \frac{\partial}{\partial x_d}$ or $|\nabla |= \mathcal{F}^{-1}[|\xi | \mathcal{F}]$. We prove that almost sure local in time well-posedness, small data global in time well-posedness and scattering hold in $H^s(\R ^d)$ with $s> \max \left( \frac{d-1}{d} s_c , \frac{s_c}{2}, s_c - \frac{d}{2(d+1)} \right)$ for $d+m \ge 5$, where $s$ is below the scaling critical regularity $s_c := \frac{d}{2}-\frac{1}{m-1}$. | [
"Mathematics Archive->math.AP"
] | "2015-08-10T08:15:03Z" |
0912.0362 | Anderson Localization of Classical Waves in Weakly Scattering Metamaterials | We study the propagation and localization of classical waves in one-dimensional disordered structures composed of alternating layers of left- and right-handed materials (mixed stacks) and compare them to the structures composed of different layers of the same material (homogeneous stacks). For weakly scattering layers, we have developed an effective analytical approach and have calculated the transmission length within a wide region of the input parameters. When both refractive index and layer thickness of a mixed stack are random, the transmission length in the long-wave range of the localized regime exhibits a quadratic power wavelength dependence with the coefficients different for mixed and homogeneous stacks. Moreover, the transmission length of a mixed stack differs from reciprocal of the Lyapunov exponent of the corresponding infinite stack. In both the ballistic regime of a mixed stack and in the near long-wave region of a homogeneous stack, the transmission length of a realization is a strongly fluctuating quantity. In the far long-wave part of the ballistic region, the homogeneous stack becomes effectively uniform and the transmission length fluctuations are weaker. The crossover region from the localization to the ballistic regime is relatively narrow for both mixed and homogeneous stacks. In mixed stacks with only refractive-index disorder, Anderson localization at long wavelengths is substantially suppressed, with the localization length growing with the wavelength much faster than for homogeneous stacks. The crossover region becomes essentially wider and transmission resonances appear only in much longer stacks. All theoretical predictions are in an excellent agreement with the results of numerical simulations. | [
"Physics Archive->cond-mat->cond-mat.dis-nn",
"Physics Archive->cond-mat->cond-mat.mes-hall"
] | "2009-12-02T08:43:12Z" |
1805.01815 | Effective damping enhancement in noncollinear spin structures | Damping mechanisms in magnetic systems determine the lifetime, diffusion and transport properties of magnons, domain walls, magnetic vortices, and skyrmions. Based on the phenomenological Landau-Lifshitz-Gilbert equation, here the effective damping parameter in noncollinear magnetic systems is determined describing the linewidth in resonance experiments or the decay parameter in time-resolved measurements. It is shown how the effective damping can be calculated from the elliptic polarization of magnons, arising due to the noncollinear spin arrangement. It is concluded that the effective damping is larger than the Gilbert damping, and it may significantly differ between excitation modes. Numerical results for the effective damping are presented for the localized magnons in isolated skyrmions, with parameters based on the Pd/Fe/Ir(111) model-type system. | [
"Physics Archive->cond-mat->cond-mat.mtrl-sci"
] | "2018-05-04T15:01:49Z" |
1910.01324 | Gas filaments of the cosmic web located around active galaxies in a proto-cluster | Cosmological simulations predict the Universe contains a network of intergalactic gas filaments, within which galaxies form and evolve. However, the faintness of any emission from these filaments has limited tests of this prediction. We report the detection of rest-frame ultraviolet Lyman-alpha radiation from multiple filaments extending more than one megaparsec between galaxies within the SSA 22 proto-cluster at a redshift of 3.1. Intense star formation and supermassive black-hole activity is occurring within the galaxies embedded in these structures, which are the likely sources of the elevated ionizing radiation powering the observed Lyman-alpha emission. Our observations map the gas in filamentary structures of the type thought to fuel the growth of galaxies and black holes in massive proto-clusters. | [
"Physics Archive->astro-ph->astro-ph.CO",
"Physics Archive->astro-ph->astro-ph.GA"
] | "2019-10-03T07:02:26Z" |
1302.1261 | Second main theorem and unicity of meromorphic mappings for hypersurfaces of projective varieties in subgeneral position | The purpose of this article is twofold. The first is to prove a second main theorem for meromorphic mappings of $\C^m$ into a complex projective variety intersecting hypersurfaces in subgeneral position with truncated counting functions. The second is to show a uniqueness theorem for these mappings which share few hypersurfaces without counting multiplicity. | [
"Mathematics Archive->math.CV"
] | "2013-02-06T04:24:10Z" |
1810.08066 | Electromagnetic field around boosted rotating black hole | The exact analytic solutions of the Maxwell equations in the exterior of a boosted rotating black hole immersed in an external magnetic field are obtained. The effect of boost as well as electromagnetic field on charged particle motion and energy extraction process -- magnetic Penrose process around black hole is studied. It justifies however the well known statement that magnetic field greatly increases efficiency of energy extraction which is further boosted by the boost velocity. | [
"Physics Archive->gr-qc"
] | "2018-10-17T09:21:47Z" |
1404.6894 | On the spine-layer scenario for the very high-energy emission of NGC 1275 | We discuss the $\gamma$-ray emission of the radiogalaxy NGC 1275 (the central galaxy of the Perseus Cluster), detected by Fermi-LAT and MAGIC, in the framework of the "spine-layer" scenario, in which the jet is assumed to be characterized by a velocity structure, with a fast spine surrounded by a slower layer. The existence of such a structure in the parsec scale jet of NGC 1275 has been recently proved through VLBI observations. We discuss the constraints that the observed spectral energy distribution imposes to the parameters and we present three alternative models, corresponding to three different choices of the angles between the jet and the line of sight ($\theta_{\rm v}=6^{\circ}, 18^{\circ}$ and 25$^{\circ}$). While for the the case with $\theta_{\rm v}=6^{\circ}$ we obtain an excellent fit, we consider this solution unlikely, since such small angles seems to be excluded by radio observations of the large-scale jet. For $\theta_{\rm v}=25^{\circ}$ the required large intrinsic luminosity of the soft (IR--optical) component of the spine determines a large optical depth for $\gamma$-rays through the pair production scattering $\gamma \gamma\rightarrow e^+ e^-$, implying a narrow cut--off at $\sim50$~GeV. We conclude that intermediate angles are required. In this case the low frequency and the high--energy emissions are produced by two separate regions and, in principle, a full variety of correlations is expected. The correlation observed between the optical and the $\gamma$-ray flux, close to linearity, is likely linked to variations of the emissivity of the spine. | [
"Physics Archive->astro-ph->astro-ph.HE"
] | "2014-04-28T08:24:21Z" |
2007.13509 | Hyper Resolution Two Photon Direct Laser Writing using ENZ Nano-Cavity | A novel technique is reported to improve the resolution of two-photon direct laser writing lithography. Thanks to the high collimation enabled by extraordinary $\varepsilon_{NZ}$ (near-zero) metamaterial features, ultra-thin dielectric hyper resolute nanostructures are within reach. With respect to the standard direct laser writing approach, a size reduction of $89\%$ and $50\%$ , in height and width respectively, is achieved with the height of the structures adjustable between 5nm and 50nm. The retrieved 2D fabrication parameters are exploited for fabricating hyper resolute 3D structures. In particular, a highly detailed dielectric bas-relief (500 nm of full height) of Da Vinci's \textit{"Lady with an Ermine"} has been realized. The proof-of-concept result shows intriguing cues for the current and trendsetting research scenario in anti-counterfeiting applications, flat optics and photonics. | [
"Physics Archive->physics->physics.app-ph"
] | "2020-07-27T12:51:10Z" |
hep-ph/0110233 | Constraints on heavy Z' couplings from \Delta S = 2 B^- -> K^- K^- \pi^+ decay | The heavy Z' boson with family nonuniversal couplings can introduce flavour changing effects. Constraints on nondiagonal Z' couplings coming from the \mu-e conversion in a muonic atom, K^0 - \bar{K^0} and B - \bar{B} mixing, epsilon and epsilon'/ \epsilon CP- violating coefficients have been already established. By using the OPAL upper bound of the branching ratio for the B^- -> K^- K^- \pi^+ decay, we indicate additional constraints on the Z' couplings. We comment also on the constraints of Z' couplings coming from the b->d d \bar{s} transition. The constraint obtained here from the upper bound of the B^- -> K^- K^- \pi^+ decay involves a different combination of couplings than those previously presented, but is much weaker. | [
"Physics Archive->hep->hep-ph"
] | "2001-10-17T14:41:10Z" |
1506.07380 | Nonlinear Bell inequalities tailored for quantum networks | In a quantum network, distant observers sharing physical resources emitted by independent sources can establish strong correlations, which defy any classical explanation in terms of local variables. We discuss the characterization of nonlocal correlations in such a situation, when compared to those that can be generated in networks distributing independent local variables. We present an iterative procedure for constructing Bell inequalities tailored for networks: starting from a given network, and a corresponding Bell inequality, our technique provides new Bell inequalities for a more complex network, involving one additional source and one additional observer. The relevance of our method is illustrated on a variety of networks, for which we demonstrate significant quantum violations. | [
"Physics Archive->quant-ph"
] | "2015-06-24T14:28:01Z" |
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