text
null | inputs
dict | prediction
null | prediction_agent
null | annotation
list | annotation_agent
null | multi_label
bool 1
class | explanation
null | id
stringlengths 1
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{
"abstract": " We consider the constrained assortment optimization problem under the mixed\nmultinomial logit model. Even moderately sized instances of this problem are\nchallenging to solve directly using standard mixed-integer linear optimization\nformulations. This has motivated recent research exploring customized\noptimization strategies and approximation techniques. In contrast, we develop a\nnovel conic quadratic mixed-integer formulation. This new formulation, together\nwith McCormick inequalities exploiting the capacity constraints, enables the\nsolution of large instances using commercial optimization software.\n",
"title": "A Conic Integer Programming Approach to Constrained Assortment Optimization under the Mixed Multinomial Logit Model"
}
| null | null | null | null | true | null |
11801
| null |
Default
| null | null |
null |
{
"abstract": " We have obtained the energy spectra of cosmic ray He, B, C, O, Mg, S and Fe\nnuclei in the range 0.5-1.5 GeV/nuc and above using the penetrating particle\nmode of the High Energy Telescope, part of the Cosmic Ray Science (CRS)\nexperiment on Voyagers 1 and 2. The data analysis procedures are the same as\nthose used to obtain similar spectra from the identical V2 HET telescope while\nit was in the heliosphere between about 23 and 54 AU. The time period of\nanalysis includes 4 years of data beyond the heliopause (HP). These new\ninterstellar spectra are compared with various earlier experiments at the same\nenergies at the Earth to determine the solar modulation parameter, phi. These\nnew spectra are also compared with recent measurements of the spectra of the\nsame nuclei measured by the same telescope at low energies. It is found that\nthe ratio of intensities at 100 MeV/nuc to those at 1.0 GeV/nuc are\nsignificantly Z dependent. Some of this Z dependence can be explained by the Z2\ndependence of energy loss by ionization in the 7-10 g/cm2 of interstellar H and\nHe traversed by cosmic rays of these energies in the galaxy; some by the Z\ndependent loss due to nuclear interactions in this same material; some by\npossible differences in the source spectra of these nuclei and some by the\nnon-uniformity of the source distribution and propagation conditions. The\nobserved features of the spectra, also including a Z dependence of the peak\nintensities of the various nuclei, pose interesting problems related to the\npropagation and source distribution of these cosmic rays.\n",
"title": "Voyager 1 Measurements Beyond the Heliopause of Galactic Cosmic Ray Helium, Boron, Carbon, Oxygen, Magnesium, Silicon and Iron Nuclei with Energies 0.5 to >1.5 GeV/nuc"
}
| null | null |
[
"Physics"
] | null | true | null |
11802
| null |
Validated
| null | null |
null |
{
"abstract": " Advanced optimization algorithms such as Newton method and AdaGrad benefit\nfrom second order derivative or second order statistics to achieve better\ndescent directions and faster convergence rates. At their heart, such\nalgorithms need to compute the inverse or inverse square root of a matrix whose\nsize is quadratic of the dimensionality of the search space. For high\ndimensional search spaces, the matrix inversion or inversion of square root\nbecomes overwhelming which in turn demands for approximate methods. In this\nwork, we propose a new matrix approximation method which divides a matrix into\nblocks and represents each block by one or two numbers. The method allows\nefficient computation of matrix inverse and inverse square root. We apply our\nmethod to AdaGrad in training deep neural networks. Experiments show\nencouraging results compared to the diagonal approximation.\n",
"title": "Block Mean Approximation for Efficient Second Order Optimization"
}
| null | null | null | null | true | null |
11803
| null |
Default
| null | null |
null |
{
"abstract": " We propose a novel formulation for approximating reachable sets through a\nminimum discounted reward optimal control problem. The formulation yields a\ncontinuous solution that can be obtained by solving a Hamilton-Jacobi equation.\nFurthermore, the numerical approximation to this solution can be obtained as\nthe unique fixed-point to a contraction mapping. This allows for more efficient\nsolution methods that could not be applied under traditional formulations for\nsolving reachable sets. In addition, this formulation provides a link between\nreinforcement learning and learning reachable sets for systems with unknown\ndynamics, allowing algorithms from the former to be applied to the latter. We\nuse two benchmark examples, double integrator, and pursuit-evasion games, to\nshow the correctness of the formulation as well as its strengths in comparison\nto previous work.\n",
"title": "A Minimum Discounted Reward Hamilton-Jacobi Formulation for Computing Reachable Sets"
}
| null | null | null | null | true | null |
11804
| null |
Default
| null | null |
null |
{
"abstract": " We prove a continuous embedding that allows us to obtain a boundary trace\nimbedding result for anisotropic Musielak-Orlicz spaces, which we then apply to\nobtain an existence result for Neumann problems with nonlinearities on the\nboundary associated to some anisotropic nonlinear elliptic equations in\nMusielak-Orlicz spaces constructed from Musielak-Orlicz functions on which and\non their conjugates we do not assume the $\\Delta_2$-condition. The uniqueness\nis also studied.\n",
"title": "Imbedding results in Musielak-Orlicz spaces with an application to anisotropic nonlinear Neumann problems"
}
| null | null |
[
"Mathematics"
] | null | true | null |
11805
| null |
Validated
| null | null |
null |
{
"abstract": " The new cyber attack pattern of advanced persistent threat (APT) has posed a\nserious threat to modern society. This paper addresses the APT defense problem,\ni.e., the problem of how to effectively defend against an APT campaign. Based\non a novel APT attack-defense model, the effectiveness of an APT defense\nstrategy is quantified. Thereby, the APT defense problem is modeled as an\noptimal control problem, in which an optimal control stands for a most\neffective APT defense strategy. The existence of an optimal control is proved,\nand an optimality system is derived. Consequently, an optimal control can be\nfigured out by solving the optimality system. Some examples of the optimal\ncontrol are given. Finally, the influence of some factors on the effectiveness\nof an optimal control is examined through computer experiments. These findings\nhelp organizations to work out policies of defending against APTs.\n",
"title": "Defend against advanced persistent threats: An optimal control approach"
}
| null | null | null | null | true | null |
11806
| null |
Default
| null | null |
null |
{
"abstract": " Autonomous driving is getting a lot of attention in the last decade and will\nbe the hot topic at least until the first successful certification of a car\nwith Level 5 autonomy. There are many public datasets in the academic\ncommunity. However, they are far away from what a robust industrial production\nsystem needs. There is a large gap between academic and industrial setting and\na substantial way from a research prototype, built on public datasets, to a\ndeployable solution which is a challenging task. In this paper, we focus on bad\npractices that often happen in the autonomous driving from an industrial\ndeployment perspective. Data design deserves at least the same amount of\nattention as the model design. There is very little attention paid to these\nissues in the scientific community, and we hope this paper encourages better\nformalization of dataset design. More specifically, we focus on the datasets\ndesign and validation scheme for autonomous driving, where we would like to\nhighlight the common problems, wrong assumptions, and steps towards avoiding\nthem, as well as some open problems.\n",
"title": "Challenges in Designing Datasets and Validation for Autonomous Driving"
}
| null | null | null | null | true | null |
11807
| null |
Default
| null | null |
null |
{
"abstract": " Though deep neural networks have achieved significant progress on various\ntasks, often enhanced by model ensemble, existing high-performance models can\nbe vulnerable to adversarial attacks. Many efforts have been devoted to\nenhancing the robustness of individual networks and then constructing a\nstraightforward ensemble, e.g., by directly averaging the outputs, which\nignores the interaction among networks. This paper presents a new method that\nexplores the interaction among individual networks to improve robustness for\nensemble models. Technically, we define a new notion of ensemble diversity in\nthe adversarial setting as the diversity among non-maximal predictions of\nindividual members, and present an adaptive diversity promoting (ADP)\nregularizer to encourage the diversity, which leads to globally better\nrobustness for the ensemble by making adversarial examples difficult to\ntransfer among individual members. Our method is computationally efficient and\ncompatible with the defense methods acting on individual networks. Empirical\nresults on various datasets verify that our method can improve adversarial\nrobustness while maintaining state-of-the-art accuracy on normal examples.\n",
"title": "Improving Adversarial Robustness via Promoting Ensemble Diversity"
}
| null | null | null | null | true | null |
11808
| null |
Default
| null | null |
null |
{
"abstract": " The issue on the effect of interactions in topological states concerns not\nonly interacting topological phases but also novel symmetry-breaking phases and\nphase transitions. Here we study the interaction effect on Majorana zero modes\n(MZMs) bound to a square vortex lattice in two-dimensional (2D) topological\nsuperconductors. Under the neutrality condition, where single-body\nhybridization between MZMs is prohibited by an emergent symmetry, a minimal\nsquare-lattice model for MZMs can be faithfully mapped to a quantum spin model,\nwhich has no sign problem in the world-line quantum Monte Carlo simulation.\nGuided by an insight from a further duality mapping, we demonstrate that the\ninteraction induces a Majorana stripe state, a gapped state spontaneously\nbreaking lattice translational and rotational symmetries, as opposed to the\npreviously conjectured topological quantum criticality. Away from neutrality, a\nmean-field theory suggests a quantum critical point induced by hybridization.\n",
"title": "Majorana stripe order on the surface of a three-dimensional topological insulator"
}
| null | null | null | null | true | null |
11809
| null |
Default
| null | null |
null |
{
"abstract": " Does academic engagement accelerate or crowd out the commercialization of\nuniversity knowledge? Research on this topic seldom considers the impact of the\ninstitutional environment, especially when a formal institution for encouraging\nthe commercial activities of scholars has not yet been established. This study\ninvestigates this question in the context of China, which is in the\ninstitutional transition stage. Based on a survey of scholars from Shanghai\nMaritime University, we demonstrate that academic engagement has a positive\nimpact on commercialization and that this impact is greater for risk-averse\nscholars than for other risk-seeking scholars. Our results suggest that in an\ninstitutional transition environment, the government should consider\nencouraging academic engagement to stimulate the commercialization activities\nof conservative scholars.\n",
"title": "Academic Engagement and Commercialization in an Institutional Transition Environment: Evidence from Shanghai Maritime University"
}
| null | null | null | null | true | null |
11810
| null |
Default
| null | null |
null |
{
"abstract": " We present a novel Affine-Gradient based Local Binary Pattern (AGLBP)\ndescriptor for texture classification. It is very hard to describe complicated\ntexture using single type information, such as Local Binary Pattern (LBP),\nwhich just utilizes the sign information of the difference between the pixel\nand its local neighbors. Our descriptor has three characteristics: 1) In order\nto make full use of the information contained in the texture, the\nAffine-Gradient, which is different from Euclidean-Gradient and invariant to\naffine transformation is incorporated into AGLBP. 2) An improved method is\nproposed for rotation invariance, which depends on the reference direction\ncalculating respect to local neighbors. 3) Feature selection method,\nconsidering both the statistical frequency and the intraclass variance of the\ntraining dataset, is also applied to reduce the dimensionality of descriptors.\nExperiments on three standard texture datasets, Outex12, Outex10 and KTH-TIPS2,\nare conducted to evaluate the performance of AGLBP. The results show that our\nproposed descriptor gets better performance comparing to some state-of-the-art\nrotation texture descriptors in texture classification.\n",
"title": "Affine-Gradient Based Local Binary Pattern Descriptor for Texture Classiffication"
}
| null | null |
[
"Computer Science"
] | null | true | null |
11811
| null |
Validated
| null | null |
null |
{
"abstract": " We combine aspects of the notions of finite decomposition complexity and\nasymptotic property C into a notion that we call finite APC-decomposition\ncomplexity. Any space with finite decomposition complexity has finite\nAPC-decomposition complexity and any space with asymptotic property C has\nfinite APC-decomposition complexity. Moreover, finite APC-decomposition\ncomplexity implies property A for metric spaces. We also show that finite\nAPC-decomposition complexity is preserved by direct products of groups and\nspaces, amalgamated products of groups, and group extensions, among other\nconstructions.\n",
"title": "Decomposition theorems for asymptotic property C and property A"
}
| null | null |
[
"Mathematics"
] | null | true | null |
11812
| null |
Validated
| null | null |
null |
{
"abstract": " We consider steady nonlinear free surface flow past an arbitrary bottom\ntopography in three dimensions, concentrating on the shape of the wave pattern\nthat forms on the surface of the fluid. Assuming ideal fluid flow, the problem\nis formulated using a boundary integral method and discretised to produce a\nnonlinear system of algebraic equations. The Jacobian of this system is dense\ndue to integrals being evaluated over the entire free surface. To overcome the\ncomputational difficulty and large memory requirements, a Jacobian-free Newton\nKrylov (JFNK) method is utilised. Using a block-banded approximation of the\nJacobian from the linearised system as a preconditioner for the JFNK scheme, we\nfind significant reductions in computational time and memory required for\ngenerating numerical solutions. These improvements also allow for a larger\nnumber of mesh points over the free surface and the bottom topography. We\npresent a range of numerical solutions for both subcritical and supercritical\nregimes, and for a variety of bottom configurations. We discuss nonlinear\nfeatures of the wave patterns as well as their relationship to ship wakes.\n",
"title": "Three dimensional free-surface flow over arbitrary bottom topography"
}
| null | null | null | null | true | null |
11813
| null |
Default
| null | null |
null |
{
"abstract": " $La_xCa_{1-x}MnO_3$ (LCMO) has been studied in the framework of density\nfunctional theory (DFT) using Hubbard-U correction. We show that the formation\nof spin-polarons of different configurations is possible in the G-type\nantiferromagentic phase. We also show that the spin-polaron (SP) solutions are\nstabilized due to an interplay of magnetic and lattice effects at lower La\nconcentrations and mostly due to the lattice contribution at larger\nconcentrations. Our results indicate that the development of SPs is unfavorable\nin the C- and A-type antiferromagnetic phases. The theoretically obtained\nmagnetic state diagram is in good agreement with previously reported\nexperimental results\n",
"title": "Spin-polaron formation and magnetic state diagram in La doped $CaMnO_3$"
}
| null | null | null | null | true | null |
11814
| null |
Default
| null | null |
null |
{
"abstract": " We analyze time evolution of statistical distributions of citations to\nscientific papers published in one year. While these distributions can be\nfitted by a power-law dependence we find that they are nonstationary and the\nexponent of the power law fit decreases with time and does not come to\nsaturation. We attribute the nonstationarity of citation distributions to\ndifferent longevity of the low-cited and highly-cited papers. By measuring\ncitation trajectories of papers we found that citation careers of the low-cited\npapers come to saturation after 10-15 years while those of the highly-cited\npapers continue to increase indefinitely: the papers that exceed some citation\nthreshold become runaways. Thus, we show that although citation distribution\ncan look as a power-law, it is not scale-free and there is a hidden dynamic\nscale associated with the onset of runaways. We compare our measurements to our\nrecently developed model of citation dynamics based on\ncopying/redirection/triadic closure and find explanations to our empirical\nobservations.\n",
"title": "Power-law citation distributions are not scale-free"
}
| null | null |
[
"Computer Science"
] | null | true | null |
11815
| null |
Validated
| null | null |
null |
{
"abstract": " In the era of vast spectroscopic surveys focusing on Galactic stellar\npopulations, astronomers want to exploit the large quantity and good quality of\ndata to derive their atmospheric parameters without losing precision from\nautomatic procedures. In this work, we developed a new spectral package, FASMA,\nto estimate the stellar atmospheric parameters (namely effective temperature,\nsurface gravity, and metallicity) in a fast and robust way. This method is\nsuitable for spectra of FGK-type stars in medium and high resolution. The\nspectroscopic analysis is based on the spectral synthesis technique using the\nradiative transfer code, MOOG. The line list is comprised of mainly iron lines\nin the optical spectrum. The atomic data are calibrated after the Sun and\nArcturus. We use two comparison samples to test our method, i) a sample of 451\nFGK-type dwarfs from the high resolution HARPS spectrograph, and ii) the\nGaia-ESO benchmark stars using both high and medium resolution spectra. We\nexplore biases in our method from the analysis of synthetic spectra covering\nthe parameter space of our interest. We show that our spectral package is able\nto provide reliable results for a wide range of stellar parameters, different\nrotational velocities, different instrumental resolutions, and for different\nspectral regions of the VLT-GIRAFFE spectrographs, used among others for the\nGaia-ESO survey. FASMA estimates stellar parameters in less than 15 min for\nhigh resolution and 3 min for medium resolution spectra. The complete package\nis publicly available to the community.\n",
"title": "Atmospheric stellar parameters for large surveys using FASMA, a new spectral synthesis package"
}
| null | null | null | null | true | null |
11816
| null |
Default
| null | null |
null |
{
"abstract": " By using the unfolding operators for periodic homogenization, we give a\ngeneral compactness result for a class of functions defined on bounded domains\npresenting perforations of two different size. Then we apply this result to the\nhomogenization of the flow of a Bingham fluid in a porous medium with solid\nobstacles of different size. Next we give the interpretation of the limit\nproblem in term of a non linear Darcy law.\n",
"title": "Bingham flow in porous media with obstacles of different size"
}
| null | null | null | null | true | null |
11817
| null |
Default
| null | null |
null |
{
"abstract": " In the Sachdev-Ye-Kitaev model, we argue that the entanglement entropy of any\neigenstate (including the ground state) obeys a volume law, whose coefficient\ncan be calculated analytically from the energy and subsystem size. We expect\nthat the argument applies to a broader class of chaotic models with all-to-all\ninteractions.\n",
"title": "Eigenstate entanglement in the Sachdev-Ye-Kitaev model"
}
| null | null |
[
"Physics"
] | null | true | null |
11818
| null |
Validated
| null | null |
null |
{
"abstract": " Inspired by the work of Henn, Lannes and Schwartz on unstable algebras over\nthe Steenrod algebra modulo nilpotents, a characterization of unstable algebras\nthat are $A$-finitely generated up to nilpotents is given in terms of the\nassociated presheaf, by introducing the notion of a finite presheaf. In\nparticular, this gives the natural characterization of the (co)analytic\npresheaves that are important in the theory of Henn, Lannes and Schwartz.\nHowever, finite presheaves remain imperfectly understood, as illustrated by\nexamples. One important class of examples is shown to be provided by unstable\nalgebras of finite transcendence degree (under a necessary weak finiteness\ncondition).\nFor unstable Hopf algebras, it is shown that the situation is much better:\nthe associated presheaf is finite if and only if its growth function is\npolynomial. This leads to a description of unstable Hopf algebras modulo\nnilpotents in the spirit of Henn, Lannes and Schwartz.\n",
"title": "Finite presheaves and $A$-finite generation of unstable algebras mod nilpotents"
}
| null | null | null | null | true | null |
11819
| null |
Default
| null | null |
null |
{
"abstract": " In single star systems like our own Solar system, comets dominate the mass\nbudget of bodies that are ejected into interstellar space, since they form\nfurther away and are less tightly bound. However 1I/`Oumuamua, the first\ninterstellar object detected, appears asteroidal in its spectra and in its lack\nof detectable activity. We argue that the galactic budget of interstellar\nobjects like 1I/`Oumuamua should be dominated by planetesimal material ejected\nduring planet formation in circumbinary systems, rather than in single star\nsystems or widely separated binaries. We further show that in circumbinary\nsystems, rocky bodies should be ejected in comparable numbers to icy ones. This\nsuggests that a substantial fraction of additional interstellar objects\ndiscovered in the future should display an active coma. We find that the rocky\npopulation, of which 1I/`Oumuamua seems to be a member, should be predominantly\nsourced from A-type and late B-star binaries.\n",
"title": "Ejection of rocky and icy material from binary star systems: Implications for the origin and composition of 1I/`Oumuamua"
}
| null | null | null | null | true | null |
11820
| null |
Default
| null | null |
null |
{
"abstract": " We study the two-photon laser excitation to the 5D$_{5/2}$ energy level of\n$^{85}$Rb atoms contained in the interstices of a porous material made from\nsintered ground glass with typical pore dimensions in the 10 - 100 $\\mu$m\nrange. The excitation spectra show unusual flat-top lineshapes which are shown\nto be the consequence of wave-vector randomization of the laser light in the\nporous material. For large atomic densities, the spectra are affected by\nradiation trapping around the D2 transitions. The effect of the transient\natomic response limited by time of flight between pores walls appears to have a\nminor influence in the excitation spectra. It is however revealed by the\nshortening of the temporal evolution of the emitted blue light following a\nsudden switch-off of the laser excitation.\n",
"title": "Two-photon excitation of rubidium atoms inside porous glass"
}
| null | null | null | null | true | null |
11821
| null |
Default
| null | null |
null |
{
"abstract": " A Bose-Einstein condensate confined in ring shaped lattices interrupted by a\nweak link and pierced by an effective magnetic flux defines the atomic\ncounterpart of the superconducting quantum interference device: the atomtronic\nquantum interference device (AQUID). In this paper, we report on the detection\nof current states in the system through a self-heterodyne protocol. Following\nthe original proposal of the NIST and Paris groups, the ring-condensate\nmany-body wave function interferes with a reference condensate expanding from\nthe center of the ring. We focus on the rf-AQUID which realizes effective qubit\ndynamics. Both the Bose-Hubbard and Gross-Pitaevskii dynamics are studied. For\nthe Bose-Hubbard dynamics, we demonstrate that the self-heterodyne protocol can\nbe applied, but higher-order correlations in the evolution of the interfering\ncondensates are measured to readout of the current states of the system. We\nstudy how states with macroscopic quantum coherence can be told apart analyzing\nthe noise in the time of flight of the ring condensate.\n",
"title": "Readout of the atomtronic quantum interference device"
}
| null | null | null | null | true | null |
11822
| null |
Default
| null | null |
null |
{
"abstract": " Deep learning networks have achieved state-of-the-art accuracies on computer\nvision workloads like image classification and object detection. The performant\nsystems, however, typically involve big models with numerous parameters. Once\ntrained, a challenging aspect for such top performing models is deployment on\nresource constrained inference systems - the models (often deep networks or\nwide networks or both) are compute and memory intensive. Low-precision numerics\nand model compression using knowledge distillation are popular techniques to\nlower both the compute requirements and memory footprint of these deployed\nmodels. In this paper, we study the combination of these two techniques and\nshow that the performance of low-precision networks can be significantly\nimproved by using knowledge distillation techniques. Our approach, Apprentice,\nachieves state-of-the-art accuracies using ternary precision and 4-bit\nprecision for variants of ResNet architecture on ImageNet dataset. We present\nthree schemes using which one can apply knowledge distillation techniques to\nvarious stages of the train-and-deploy pipeline.\n",
"title": "Apprentice: Using Knowledge Distillation Techniques To Improve Low-Precision Network Accuracy"
}
| null | null | null | null | true | null |
11823
| null |
Default
| null | null |
null |
{
"abstract": " Traditional web search forces the developers to leave their working\nenvironments and look for solutions in the web browsers. It often does not\nconsider the context of their programming problems. The context-switching\nbetween the web browser and the working environment is time-consuming and\ndistracting, and the keyword-based traditional search often does not help much\nin problem solving. In this paper, we propose an Eclipse IDE-based web search\nsolution that collects the data from three web search APIs-- Google, Yahoo,\nBing and a programming Q & A site-- Stack Overflow. It then provides search\nresults within IDE taking not only the content of the selected error into\naccount but also the problem context, popularity and search engine\nrecommendation of the result links. Experiments with 25 run time errors and\nexceptions show that the proposed approach outperforms the keyword-based search\napproaches with a recommendation accuracy of 96%. We also validate the results\nwith a user study involving five prospective participants where we get a result\nagreement of 64.28%. While the preliminary results are promising, the approach\nneeds to be further validated with more errors and exceptions followed by a\nuser study with more participants to establish itself as a complete IDE-based\nweb search solution.\n",
"title": "An IDE-Based Context-Aware Meta Search Engine"
}
| null | null | null | null | true | null |
11824
| null |
Default
| null | null |
null |
{
"abstract": " In this paper, we propose the first homomorphic based proxy re-encryption\n(HPRE) solution that allows different users to share data they outsourced\nhomomorphically encrypted using their respective public keys with the\npossibility to process such data remotely. More clearly, this scheme makes\npossible to switch the public encryption key to another one without the help of\na trusted third party. Its originality stands on a method we propose so as to\ncompute the difference between two encrypted data without decrypting them and\nwith no extra communications. Basically, in our HPRE scheme, the two users, the\ndelegator and the delegate, ask the cloud server to generate an encrypted noise\nbased on a secret key, both users previously agreed on. Based on our solution\nfor comparing encrypted data, the cloud computes in clear the differences\nin-between the encrypted noise and the encrypted data of the delegator,\nobtaining thus blinded data. By next the cloud encrypts these differences with\nthe public key of the delegate. As the noise is also known of the delegate,\nthis one just has to remove it to get access to the data encrypted with his\npublic key. This solution has been experimented in the case of the sharing of\nimages outsourced into a semihonest cloud server.\n",
"title": "Sharing Data Homomorphically Encrypted with Different Encryption Keys"
}
| null | null | null | null | true | null |
11825
| null |
Default
| null | null |
null |
{
"abstract": " We explore the competition and coupling of vibrational and electronic\ncontributions to the heat capacity of Al and Al$_3$Sc at temperatures below 50\nK combining experimental calorimetry with highly converged finite temperature\ndensity functional theory calculations. We find that semilocal exchange\ncorrelation functionals accurately describe the rich feature set observed for\nthese temperatures, including electron-phonon coupling. Using different\nrepresentations of the heat capacity, we are therefore able to identify and\nexplain deviations from the Debye behaviour in the low-temperature limit and in\nthe temperature regime 30 - 50 K as well as the reduction of these features due\nto the addition of Sc.\n",
"title": "Low temperature features in the heat capacity of unary metals and intermetallics for the example of bulk aluminum and Al$_3$Sc"
}
| null | null | null | null | true | null |
11826
| null |
Default
| null | null |
null |
{
"abstract": " We demonstrate how electric fields with arbitrary time profile can be used to\ncontrol the time-dependent parameters of spin and orbital exchange\nHamiltonians. Analytic expressions for the exchange constants are derived from\na time-dependent Schrieffer-Wolff transformation, and the validity of the\nresulting effective Hamiltonian is verified for the case of a quarter-filled\ntwo-orbital Hubbard model, by comparing to the results of a full nonequilibrium\ndynamical mean-field theory simulation. The ability to manipulate Hamiltonians\nwith arbitrary time-dependent fields, beyond the paradigm of Floquet\nengineering, opens the possibility to control intertwined spin and orbital\norder using laser or THz pulses which are tailored to minimize electronic\nexcitations.\n",
"title": "Designing spin and orbital exchange Hamiltonians with ultrashort electric field transients"
}
| null | null |
[
"Physics"
] | null | true | null |
11827
| null |
Validated
| null | null |
null |
{
"abstract": " Computation of semantic similarity between concepts is an important\nfoundation for many research works. This paper focuses on IC computing methods\nand IC measures, which estimate the semantic similarities between concepts by\nexploiting the topological parameters of the taxonomy. Based on analyzing\nrepresentative IC computing methods and typical semantic similarity measures,\nwe propose a new hybrid IC computing method. Through adopting the parameter\ndhyp and lch, we utilize the new IC computing method and propose a novel\ncomprehensive measure of semantic similarity between concepts. An experiment\nbased on WordNet \"is a\" taxonomy has been designed to test representative\nmeasures and our measure on benchmark dataset R&G, and the results show that\nour measure can obviously improve the similarity accuracy. We evaluate the\nproposed approach by comparing the correlation coefficients between five\nmeasures and the artificial data. The results show that our proposal\noutperforms the previous measures.\n",
"title": "A Novel Comprehensive Approach for Estimating Concept Semantic Similarity in WordNet"
}
| null | null | null | null | true | null |
11828
| null |
Default
| null | null |
null |
{
"abstract": " Associated to any closed quantum subgroup $G\\subset U_N^+$ and any index set\n$I\\subset\\{1,\\ldots,N\\}$ is a certain homogeneous space $X_{G,I}\\subset\nS^{N-1}_{\\mathbb C,+}$, called affine homogeneous space. We discuss here the\nabstract axiomatization of the algebraic manifolds $X\\subset S^{N-1}_{\\mathbb\nC,+}$ which can appear in this way, by using Tannakian duality methods.\n",
"title": "Tannakian duality for affine homogeneous spaces"
}
| null | null | null | null | true | null |
11829
| null |
Default
| null | null |
null |
{
"abstract": " In the following we show the strong comparison principle for the fractional\n$p$-Laplacian, i.e. we analyze functions $v,w$ which satisfy $v\\geq w$ in\n$\\mathbb{R}^N$ and\n\\[\n(-\\Delta)^s_pv+q(x)|v|^{p-2}v\\geq (-\\Delta)^s_pw+q(x)|w|^{p-2}w \\quad\n\\text{in $D$,}\n\\] where $s\\in(0,1)$, $p>1$, $D\\subset \\mathbb{R}^N$ is an open set, and\n$q\\in L^{\\infty}(\\mathbb{R}^N)$ is a nonnegative function. Under suitable\nconditions on $s,p$ and some regularity assumptions on $v,w$ we show that\neither $v\\equiv w$ in $\\mathbb{R}^N$ or $v>w$ in $D$. Moreover, we apply this\nresult to analyze the geometry of nonnegative solutions in starshaped rings and\nin the half space.\n",
"title": "Strong comparison principle for the fractional $p$-Laplacian and applications to starshaped rings"
}
| null | null | null | null | true | null |
11830
| null |
Default
| null | null |
null |
{
"abstract": " The distribution of metals in the intra-cluster medium encodes important\ninformation about the enrichment history and formation of galaxy clusters. Here\nwe explore the metal content of clusters in IllustrisTNG - a new suite of\ngalaxy formation simulations building on the Illustris project. Our cluster\nsample contains 20 objects in TNG100 - a ~(100 Mpc)^3 volume simulation with\n2x1820^3 resolution elements, and 370 objects in TNG300 - a ~(300 Mpc)^3 volume\nsimulation with 2x2500^3 resolution elements. The z=0 metallicity profiles\nagree with observations, and the enrichment history is consistent with\nobservational data going beyond z~1, showing nearly no metallicity evolution.\nThe abundance profiles vary only minimally within the cluster samples,\nespecially in the outskirts with a relative scatter of ~15%. The average\nmetallicity profile flattens towards the center, where we find a logarithmic\nslope of -0.1 compared to -0.5 in the outskirts. Cool core clusters have more\ncentrally peaked metallicity profiles (~0.8 solar) compared to non-cool core\nsystems (~0.5 solar), similar to observational trends. Si/Fe and O/Fe radial\nprofiles follow positive gradients. The outer abundance profiles do not evolve\nbelow z~2, whereas the inner profiles flatten towards z=0. More than ~80% of\nthe metals in the intra-cluster medium have been accreted from the\nproto-cluster environment, which has been enriched to ~0.1 solar already at\nz~2. We conclude that the intra-cluster metal distribution is uniform among our\ncluster sample, nearly time-invariant in the outskirts for more than 10 Gyr,\nand forms through a universal enrichment history.\n",
"title": "The uniformity and time-invariance of the intra-cluster metal distribution in galaxy clusters from the IllustrisTNG simulations"
}
| null | null | null | null | true | null |
11831
| null |
Default
| null | null |
null |
{
"abstract": " Click through rate (CTR) prediction is very important for Native\nadvertisement but also hard as there is no direct query intent. In this paper\nwe propose a large-scale event embedding scheme to encode the each user\nbrowsing event by training a Siamese network with weak supervision on the\nusers' consecutive events. The CTR prediction problem is modeled as a\nsupervised recurrent neural network, which naturally model the user history as\na sequence of events. Our proposed recurrent models utilizing pretrained event\nembedding vectors and an attention layer to model the user history. Our\nexperiments demonstrate that our model significantly outperforms the baseline\nand some variants.\n",
"title": "Improving Native Ads CTR Prediction by Large Scale Event Embedding and Recurrent Networks"
}
| null | null | null | null | true | null |
11832
| null |
Default
| null | null |
null |
{
"abstract": " We consider the closest lattice point problem in a distributed network\nsetting and study the communication cost and the error probability for\ncomputing an approximate nearest lattice point, using the nearest-plane\nalgorithm, due to Babai. Two distinct communication models, centralized and\ninteractive, are considered. The importance of proper basis selection is\naddressed. Assuming a reduced basis for a two-dimensional lattice, we determine\nthe approximation error of the nearest plane algorithm. The communication cost\nfor determining the Babai point, or equivalently, for constructing the\nrectangular nearest-plane partition, is calculated in the interactive setting.\nFor the centralized model, an algorithm is presented for reducing the\ncommunication cost of the nearest plane algorithm in an arbitrary number of\ndimensions.\n",
"title": "On the Communication Cost of Determining an Approximate Nearest Lattice Point"
}
| null | null | null | null | true | null |
11833
| null |
Default
| null | null |
null |
{
"abstract": " Capacity of a quantum channel characterizes the limits of reliable\ncommunication through a noisy quantum channel. This fundamental information\ntheoretic question is very well studied specially in the setting of many\nindependent uses of the channel. An important scenario, both from practical and\nconceptual point of view, is when the channel can be used only once. This is\nknown as the one-shot channel coding problem. We provide a tight\ncharacterization of the one-shot entanglement assisted classical capacity of a\nquantum channel. We arrive at our result by introducing a simple decoding\ntechnique which we refer to as position-based decoding. We also consider two\nother important quantum network scenarios: quantum channel with a jammer and\nquantum broadcast channel. For these problems, we use the recently introduced\nconvex split technique [Anshu, Devabathini and Jain 2014] in addition to\nposition based decoding. Our approach exhibits that the simultaneous use of\nthese two techniques provides a uniform and conceptually simple framework for\ndesigning communication protocols for quantum networks.\n",
"title": "One shot entanglement assisted classical and quantum communication over noisy quantum channels: A hypothesis testing and convex split approach"
}
| null | null | null | null | true | null |
11834
| null |
Default
| null | null |
null |
{
"abstract": " Conformally variational Riemannian invariants (CVIs), such as the scalar\ncurvature, are homogeneous scalar invariants which arise as the gradient of a\nRiemannian functional. We establish a wide range of stability and rigidity\nresults involving CVIs, generalizing many such results for the scalar\ncurvature.\n",
"title": "Conformally variational Riemannian invariants"
}
| null | null | null | null | true | null |
11835
| null |
Default
| null | null |
null |
{
"abstract": " One of the most promising approaches to overcome the uncertainty and dynamic\nchannel variations of millimeter wave (mmW) communications is to deploy\ndual-mode base stations that integrate both mmW and microwave ($\\mu$W)\nfrequencies. If properly designed, such dual-mode base stations can enhance\nmobility and handover in highly mobile wireless environments. In this paper, a\nnovel approach for analyzing and managing mobility in joint $\\mu$W-mmW networks\nis proposed. The proposed approach leverages device-level caching along with\nthe capabilities of dual-mode base stations to minimize handover failures,\nreduce inter-frequency measurement energy consumption, and provide seamless\nmobility in emerging dense heterogeneous networks. First, fundamental results\non the caching capabilities, including caching probability and cache duration\nare derived for the proposed dual-mode network scenario. Second, the average\nachievable rate of caching is derived for mobile users. Third, the proposed\ncache-enabled mobility management problem is formulated as a dynamic matching\ngame between mobile user equipments (MUEs) and small base stations (SBSs). The\ngoal of this game is to find a distributed handover mechanism that subject to\nthe network constraints on HOFs and limited cache sizes, allows each MUE to\nchoose between executing an HO to a target SBS, being connected to the\nmacrocell base station (MBS), or perform a transparent HO by using the cached\ncontent. The formulated matching game allows capturing the dynamics of the\nmobility management problem caused by HOFs. To solve this dynamic matching\nproblem, a novel algorithm is proposed and its convergence to a two-sided\ndynamically stable HO policy is proved. Numerical results corroborate the\nanalytical derivations and show that the proposed solution will provides\nsignificant reductions in both the HOF and energy consumption by MUEs.\n",
"title": "Caching Meets Millimeter Wave Communications for Enhanced Mobility Management in 5G Networks"
}
| null | null | null | null | true | null |
11836
| null |
Default
| null | null |
null |
{
"abstract": " Data poisoning is an attack on machine learning models wherein the attacker\nadds examples to the training set to manipulate the behavior of the model at\ntest time. This paper explores poisoning attacks on neural nets. The proposed\nattacks use \"clean-labels\"; they don't require the attacker to have any control\nover the labeling of training data. They are also targeted; they control the\nbehavior of the classifier on a $\\textit{specific}$ test instance without\ndegrading overall classifier performance. For example, an attacker could add a\nseemingly innocuous image (that is properly labeled) to a training set for a\nface recognition engine, and control the identity of a chosen person at test\ntime. Because the attacker does not need to control the labeling function,\npoisons could be entered into the training set simply by leaving them on the\nweb and waiting for them to be scraped by a data collection bot.\nWe present an optimization-based method for crafting poisons, and show that\njust one single poison image can control classifier behavior when transfer\nlearning is used. For full end-to-end training, we present a \"watermarking\"\nstrategy that makes poisoning reliable using multiple ($\\approx$50) poisoned\ntraining instances. We demonstrate our method by generating poisoned frog\nimages from the CIFAR dataset and using them to manipulate image classifiers.\n",
"title": "Poison Frogs! Targeted Clean-Label Poisoning Attacks on Neural Networks"
}
| null | null | null | null | true | null |
11837
| null |
Default
| null | null |
null |
{
"abstract": " Macroscopic models for systems involving diffusion, short-range repulsion,\nand long-range attraction have been studied extensively in the last decades. In\nthis paper we extend the analysis to a system for two species interacting with\neach other according to different inner- and intra-species attractions. Under\nsuitable conditions on this self- and crosswise attraction an interesting\neffect can be observed, namely phase separation into neighbouring regions, each\nof which contains only one of the species. We prove that the intersection of\nthe support of the stationary solutions of the continuum model for the two\nspecies has zero Lebesgue measure, while the support of the sum of the two\ndensities is simply connected.\nPreliminary results indicate the existence of phase separation, i.e. spatial\nsorting of the different species. A detailed analysis in one spatial dimension\nfollows. The existence and shape of segregated stationary solutions is shown\nvia the Krein-Rutman theorem. Moreover, for small repulsion/nonlinear\ndiffusion, also uniqueness of these stationary states is proved.\n",
"title": "Sorting Phenomena in a Mathematical Model For Two Mutually Attracting/Repelling Species"
}
| null | null |
[
"Mathematics"
] | null | true | null |
11838
| null |
Validated
| null | null |
null |
{
"abstract": " Monomolecular drug carriers based on calix[n]-arenes and -resorcinarenes\ncontaining the interior cavity can enhance the affinity and specificity of the\nosteoporosis inhibitor drug zoledronate (ZOD). In this work we investigate the\nsuitability of nine different calix[4]-arenes and -resorcinarenes based\nmacrocycles as hosts for the ZOD guest molecule by conducting {\\it ab initio}\ndensity functional theory calculations for structures and energetics of\neighteen different host-guest complexes. For the optimized molecular structures\nof the free, phosphonated, sulfonated calix[4]-arenes and -resorcinarenes, the\ngeometric sizes of their interior cavities are measured and compared with those\nof the host-guest complexes in order to check the appropriateness for\nhost-guest complex formation. Our calculations of binding energies indicate\nthat in gaseous states some of the complexes might be unstable but in aqueous\nstates almost all of the complexes can be formed spontaneously. Of the two\ndifferent docking ways, the insertion of ZOD with the \\ce{P-C-P} branch into\nthe cavity of host is easier than that with the nitrogen containing heterocycle\nof ZOD. The work will open a way for developing effective drug delivering\nsystems for the ZOD drug and promote experimentalists to synthesize them.\n",
"title": "Ab initio design of drug carriers for zoledronate guest molecule using phosphonated and sulfonated calix[4]arene and calix[4]resorcinarene host molecules"
}
| null | null |
[
"Physics"
] | null | true | null |
11839
| null |
Validated
| null | null |
null |
{
"abstract": " In visual surveillance systems, it is necessary to recognize the behavior of\npeople handling objects such as a phone, a cup, or a plastic bag. In this\npaper, to address this problem, we propose a new framework for recognizing\nobject-related human actions by graph convolutional networks using human and\nobject poses. In this framework, we construct skeletal graphs of reliable human\nposes by selectively sampling the informative frames in a video, which include\nhuman joints with high confidence scores obtained in pose estimation. The\nskeletal graphs generated from the sampled frames represent human poses related\nto the object position in both the spatial and temporal domains, and these\ngraphs are used as inputs to the graph convolutional networks. Through\nexperiments over an open benchmark and our own data sets, we verify the\nvalidity of our framework in that our method outperforms the state-of-the-art\nmethod for skeleton-based action recognition.\n",
"title": "Skeleton-based Action Recognition of People Handling Objects"
}
| null | null | null | null | true | null |
11840
| null |
Default
| null | null |
null |
{
"abstract": " We study an extension of active learning in which the learning algorithm may\nask the annotator to compare the distances of two examples from the boundary of\ntheir label-class. For example, in a recommendation system application (say for\nrestaurants), the annotator may be asked whether she liked or disliked a\nspecific restaurant (a label query); or which one of two restaurants did she\nlike more (a comparison query).\nWe focus on the class of half spaces, and show that under natural\nassumptions, such as large margin or bounded bit-description of the input\nexamples, it is possible to reveal all the labels of a sample of size $n$ using\napproximately $O(\\log n)$ queries. This implies an exponential improvement over\nclassical active learning, where only label queries are allowed. We complement\nthese results by showing that if any of these assumptions is removed then, in\nthe worst case, $\\Omega(n)$ queries are required.\nOur results follow from a new general framework of active learning with\nadditional queries. We identify a combinatorial dimension, called the\n\\emph{inference dimension}, that captures the query complexity when each\nadditional query is determined by $O(1)$ examples (such as comparison queries,\neach of which is determined by the two compared examples). Our results for half\nspaces follow by bounding the inference dimension in the cases discussed above.\n",
"title": "Active classification with comparison queries"
}
| null | null | null | null | true | null |
11841
| null |
Default
| null | null |
null |
{
"abstract": " Many digital functions studied in the literature, e.g., the summatory\nfunction of the base-$k$ sum-of-digits function, have a behavior showing some\nperiodic fluctuation. Such functions are usually studied using techniques from\nanalytic number theory or linear algebra. In this paper we develop a method\nbased on exotic numeration systems and we apply it on two examples motivated by\nthe study of generalized Pascal triangles and binomial coefficients of words.\n",
"title": "Behavior of digital sequences through exotic numeration systems"
}
| null | null | null | null | true | null |
11842
| null |
Default
| null | null |
null |
{
"abstract": " In psychological measurements, two levels should be distinguished: the\n'individual level', relative to the different participants in a given cognitive\nsituation, and the 'collective level', relative to the overall statistics of\ntheir outcomes, which we propose to associate with a notion of 'collective\nparticipant'. When the distinction between these two levels is properly\nformalized, it reveals why the modeling of the collective participant generally\nrequires beyond-quantum - non-Bornian - probabilistic models, when sequential\nmeasurements at the individual level are considered, and this though a pure\nquantum description remains valid for single measurement situations.\n",
"title": "Quantum cognition goes beyond-quantum: modeling the collective participant in psychological measurements"
}
| null | null | null | null | true | null |
11843
| null |
Default
| null | null |
null |
{
"abstract": " Line bundles of rational degree are defined using Perfectoid spaces, and\ntheir co-homology computed via standard Čech complex along with Kunneth\nformula. A new concept of `braided dimension' is introduced, which helps\nconvert the curse of infinite dimensionality into a boon, which is then used to\ndo Bezout type computations, define euler characters, describe ampleness and\nlink integer partitions with geometry. This new concept of 'Braided dimension'\ngives a space within a space within a space an infinite tower of spaces, all\nintricately braided into each other. Finally, the concept of Blow Up over\nperfectoid space is introduced.\n",
"title": "Geometry of Projective Perfectoid and Integer Partitions"
}
| null | null |
[
"Mathematics"
] | null | true | null |
11844
| null |
Validated
| null | null |
null |
{
"abstract": " Linear structural equation models relate the components of a random vector\nusing linear interdependencies and Gaussian noise. Each such model can be\nnaturally associated with a mixed graph whose vertices correspond to the\ncomponents of the random vector. The graph contains directed edges that\nrepresent the linear relationships between components, and bidirected edges\nthat encode unobserved confounding. We study the problem of generic\nidentifiability, that is, whether a generic choice of linear and confounding\neffects can be uniquely recovered from the joint covariance matrix of the\nobserved random vector. An existing combinatorial criterion for establishing\ngeneric identifiability is the half-trek criterion (HTC), which uses the\nexistence of trek systems in the mixed graph to iteratively discover\ngenerically invertible linear equation systems in polynomial time. By focusing\non edges one at a time, we establish new sufficient and necessary conditions\nfor generic identifiability of edge effects extending those of the HTC. In\nparticular, we show how edge coefficients can be recovered as quotients of\nsubdeterminants of the covariance matrix, which constitutes a determinantal\ngeneralization of formulas obtained when using instrumental variables for\nidentification.\n",
"title": "Determinantal Generalizations of Instrumental Variables"
}
| null | null | null | null | true | null |
11845
| null |
Default
| null | null |
null |
{
"abstract": " While an increasing number of two-dimensional (2D) materials, including\ngraphene and silicene, have already been realized, others have only been\npredicted. An interesting example is the two-dimensional form of silicon\ncarbide (2D-SiC). Here, we present an observation of atomically thin and\nhexagonally bonded nanosized grains of SiC assembling temporarily in graphene\noxide pores during an atomic resolution scanning transmission electron\nmicroscopy experiment. Even though these small grains do not fully represent\nthe bulk crystal, simulations indicate that their electronic structure already\napproaches that of 2D-SiC. This is predicted to be flat, but some doubts have\nremained regarding the preference of Si for sp$^{3}$ hybridization. Exploring a\nnumber of corrugated morphologies, we find completely flat 2D-SiC to have the\nlowest energy. We further compute its phonon dispersion, with a Raman-active\ntransverse optical mode, and estimate the core level binding energies. Finally,\nwe study the chemical reactivity of 2D-SiC, suggesting it is like silicene\nunstable against molecular absorption or interlayer linking. Nonetheless, it\ncan form stable van der Waals-bonded bilayers with either graphene or hexagonal\nboron nitride, promising to further enrich the family of two-dimensional\nmaterials once bulk synthesis is achieved.\n",
"title": "Computational insights and the observation of SiC nanograin assembly: towards 2D silicon carbide"
}
| null | null |
[
"Physics"
] | null | true | null |
11846
| null |
Validated
| null | null |
null |
{
"abstract": " In this paper we present a novel construction of non-homogeneous hydrodynamic\nequations from what we call quasi-Stäckel systems, that is non-commutatively\nintegrable systems constructed from appropriate maximally superintegrable\nStäckel systems. We describe the relations between Poisson algebras generated\nby quasi-Stäckel Hamiltonians and the corresponding Lie algebras of vector\nfields of non-homogeneous hydrodynamic systems. We also apply Stäckel\ntransform to obtain new non-homogeneous equations of considered type.\n",
"title": "Non-Homogeneous Hydrodynamic Systems and Quasi-Stäckel Hamiltonians"
}
| null | null |
[
"Physics"
] | null | true | null |
11847
| null |
Validated
| null | null |
null |
{
"abstract": " The Tunka Radio Extension (Tunka-Rex) is an antenna array consisting of 63\nantennas at the location of the TAIGA facility (Tunka Advanced Instrument for\ncosmic ray physics and Gamma Astronomy) in Eastern Siberia, nearby Lake Baikal.\nTunka-Rex is triggered by the air-Cherenkov array Tunka-133 during clear and\nmoonless winter nights and by the scintillator array Tunka-Grande during the\nremaining time. Tunka-Rex measures the radio emission from the same air-showers\nas Tunka-133 and Tunka-Grande, but with a higher threshold of about 100 PeV.\nDuring the first stages of its operation, Tunka-Rex has proven, that sparse\nradio arrays can measure air-showers with an energy resolution of better than\n15\\% and the depth of the shower maximum with a resolution of better than 40\ng/cm\\textsuperscript{2}. To improve and interpret our measurements as well as\nto study systematic uncertainties due to interaction models, we perform radio\nsimulations with CORSIKA and CoREAS. In this overview we present the setup of\nTunka-Rex, discuss the achieved results and the prospects of mass-composition\nstudies with radio arrays.\n",
"title": "Latest results of the Tunka Radio Extension (ISVHECRI2016)"
}
| null | null | null | null | true | null |
11848
| null |
Default
| null | null |
null |
{
"abstract": " Calculations of the correlations between the Rabi frequency on the\n$H^3\\Delta_1$ to $C^1\\Pi$ transition in ThO molecule and experimental setup\nparameters in the electron electric dipole moment (eEDM) search experiment is\nperformed. Calculations are required for estimations of systematic errors in\nthe experiment due to imperfections in laser beams used to prepare the molecule\nand read out the eEDM signal.\n",
"title": "The Rabi frequency on the $H^3Δ_1$ to $C^1Π$ transition in ThO: influence of interaction with electric and magnetic fields"
}
| null | null | null | null | true | null |
11849
| null |
Default
| null | null |
null |
{
"abstract": " Animal groups exhibit emergent properties that are a consequence of local\ninteractions. Linking individual-level behaviour to coarse-grained descriptions\nof animal groups has been a question of fundamental interest. Here, we present\ntwo complementary approaches to deriving coarse-grained descriptions of\ncollective behaviour at so-called mesoscopic scales, which account for the\nstochasticity arising from the finite sizes of animal groups. We construct\nstochastic differential equations (SDEs) for a coarse-grained variable that\ndescribes the order/consensus within a group. The first method of construction\nis based on van Kampen's system-size expansion of transition rates. The second\nmethod employs Gillespie's chemical Langevin equations. We apply these two\nmethods to two microscopic models from the literature, in which organisms\nstochastically interact and choose between two directions/choices of foraging.\nThese `binary-choice' models differ only in the types of interactions between\nindividuals, with one assuming simple pair-wise interactions, and the other\nincorporating higher-order effects. In both cases, the derived mesoscopic SDEs\nhave multiplicative, or state-dependent, noise. However, the different models\ndemonstrate the contrasting effects of noise: increasing order in the pair-wise\ninteraction model, whilst reducing order in the higher-order interaction model.\nAlthough both methods yield identical SDEs for such binary-choice, or\none-dimensional, systems, the relative tractability of the chemical Langevin\napproach is beneficial in generalizations to higher-dimensions. In summary,\nthis book chapter provides a pedagogical review of two complementary methods to\nconstruct mesoscopic descriptions from microscopic rules and demonstrates how\nresultant multiplicative noise can have counter-intuitive effects on shaping\ncollective behaviour.\n",
"title": "Deriving mesoscopic models of collective behaviour for finite populations"
}
| null | null | null | null | true | null |
11850
| null |
Default
| null | null |
null |
{
"abstract": " Using the 1-BM-C beamline at the Advanced Photon Source (APS), we have\nperformed the initial indirect x-ray imaging point-spread-function (PSF) test\nof a unique 88-mm diameter YAG:Ce single crystal of only 100-micron thickness.\nThe crystal was bonded to a fiber optic plate (FOP) for mechanical support and\nto allow the option for FO coupling to a large format camera. This\nconfiguration resolution was compared to that of self-supported 25-mm diameter\ncrystals, with and without an Al reflective coating. An upstream monochromator\nwas used to select 17-keV x-rays from the broadband APS bending magnet source\nof synchrotron radiation. The upstream, adjustable Mo collimators were then\nused to provide a series of x-ray source transverse sizes from 200 microns down\nto about 15-20 microns (FWHM) at the crystal surface. The emitted scintillator\nradiation was in this case lens coupled to the ANDOR Neo sCMOS camera, and the\nindirect x-ray images were processed offline by a MATLAB-based image processing\nprogram. Based on single Gaussian peak fits to the x-ray image projected\nprofiles, we observed a 10.5 micron PSF. This sample thus exhibited superior\nspatial resolution to standard P43 polycrystalline phosphors of the same\nthickness which would have about a 100-micron PSF. This single crystal\nresolution combined with the 88-mm diameter makes it a candidate to support\nfuture x-ray diffraction or wafer topography experiments.\n",
"title": "First Indirect X-Ray Imaging Tests With An 88-mm Diameter Single Crystal"
}
| null | null | null | null | true | null |
11851
| null |
Default
| null | null |
null |
{
"abstract": " Randomized quasi-Monte Carlo (RQMC) sampling can bring orders of magnitude\nreduction in variance compared to plain Monte Carlo (MC) sampling. The extent\nof the efficiency gain varies from problem to problem and can be hard to\npredict. This article presents an R function rhalton that produces scrambled\nversions of Halton sequences. On some problems it brings efficiency gains of\nseveral thousand fold. On other problems, the efficiency gain is minor. The\ncode is designed to make it easy to determine whether a given integrand will\nbenefit from RQMC sampling. An RQMC sample of n points in $[0,1]^d$ can be\nextended later to a larger n and/or d.\n",
"title": "A randomized Halton algorithm in R"
}
| null | null | null | null | true | null |
11852
| null |
Default
| null | null |
null |
{
"abstract": " Relational data are usually highly incomplete in practice, which inspires us\nto leverage side information to improve the performance of community detection\nand link prediction. This paper presents a Bayesian probabilistic approach that\nincorporates various kinds of node attributes encoded in binary form in\nrelational models with Poisson likelihood. Our method works flexibly with both\ndirected and undirected relational networks. The inference can be done by\nefficient Gibbs sampling which leverages sparsity of both networks and node\nattributes. Extensive experiments show that our models achieve the\nstate-of-the-art link prediction results, especially with highly incomplete\nrelational data.\n",
"title": "Leveraging Node Attributes for Incomplete Relational Data"
}
| null | null | null | null | true | null |
11853
| null |
Default
| null | null |
null |
{
"abstract": " On many parallel machines, the time LQCD applications spent in communication\nis a significant contribution to the total wall-clock time, especially in the\nstrong-scaling limit. We present a novel high-performance communication library\nthat can be used as a de facto drop-in replacement for MPI in existing\nsoftware. Its lightweight nature that avoids some of the unnecessary overhead\nintroduced by MPI allows us to improve the communication performance of\napplications without any algorithmic or complicated implementation changes. As\na first real-world benchmark, we make use of the pMR library in the coarse-grid\nsolve of the Regensburg implementation of the DD-$\\alpha$AMG algorithm. On\nrealistic lattices, we see an improvement of a factor 2x in pure communication\ntime and total execution time savings of up to 20%.\n",
"title": "pMR: A high-performance communication library"
}
| null | null | null | null | true | null |
11854
| null |
Default
| null | null |
null |
{
"abstract": " We describe a purely-multiplicative method for extending an analytic\nfunction. It calculates the value of an analytic function at a point, merely by\nmultiplying together function values and reciprocals of function values at\nother points closer to the origin. The function values are taken at the points\nof geometric sequences, independent of the function, whose geometric ratios are\narbitrary. The method exposes an \"elastic invariance\" property of all analytic\nfunctions. We show how to simplify and truncate multiplicative function\nextensions for practical calculations. If we choose each geometric ratio to be\nthe reciprocal of a power of a prime number, we obtain a prime functional\nidentity, which contains a generalization of the Möbius function (with the\nsame denominator as the Rieman zeta function), and generates prime number\nidentities.\n",
"title": "Extending a Function Just by Multiplying and Dividing Function Values: Smoothness and Prime Identities"
}
| null | null | null | null | true | null |
11855
| null |
Default
| null | null |
null |
{
"abstract": " Our daily perceptual experience is driven by different neural mechanisms that\nyield multisensory interaction as the interplay between exogenous stimuli and\nendogenous expectations. While the interaction of multisensory cues according\nto their spatiotemporal properties and the formation of multisensory\nfeature-based representations have been widely studied, the interaction of\nspatial-associative neural representations has received considerably less\nattention. In this paper, we propose a neural network architecture that models\nthe interaction of spatial-associative representations to perform causal\ninference of audiovisual stimuli. We investigate the spatial alignment of\nexogenous audiovisual stimuli modulated by associative congruence. In the\nspatial layer, topographically arranged networks account for the interaction of\naudiovisual input in terms of population codes. In the associative layer,\ncongruent audiovisual representations are obtained via the experience-driven\ndevelopment of feature-based associations. Levels of congruency are obtained as\na by-product of the neurodynamics of self-organizing networks, where the amount\nof neural activation triggered by the input can be expressed via a nonlinear\ndistance function. Our novel proposal is that activity-driven levels of\ncongruency can be used as top-down modulatory projections to spatially\ndistributed representations of sensory input, e.g. semantically related\naudiovisual pairs will yield a higher level of integration than unrelated\npairs. Furthermore, levels of neural response in unimodal layers may be seen as\nsensory reliability for the dynamic weighting of crossmodal cues. We describe a\nseries of planned experiments to validate our model in the tasks of\nmultisensory interaction on the basis of semantic congruence and unimodal cue\nreliability.\n",
"title": "Towards Modeling the Interaction of Spatial-Associative Neural Network Representations for Multisensory Perception"
}
| null | null | null | null | true | null |
11856
| null |
Default
| null | null |
null |
{
"abstract": " To reduce data collection time for deep learning of robust robotic grasp\nplans, we explore training from a synthetic dataset of 6.7 million point\nclouds, grasps, and analytic grasp metrics generated from thousands of 3D\nmodels from Dex-Net 1.0 in randomized poses on a table. We use the resulting\ndataset, Dex-Net 2.0, to train a Grasp Quality Convolutional Neural Network\n(GQ-CNN) model that rapidly predicts the probability of success of grasps from\ndepth images, where grasps are specified as the planar position, angle, and\ndepth of a gripper relative to an RGB-D sensor. Experiments with over 1,000\ntrials on an ABB YuMi comparing grasp planning methods on singulated objects\nsuggest that a GQ-CNN trained with only synthetic data from Dex-Net 2.0 can be\nused to plan grasps in 0.8sec with a success rate of 93% on eight known objects\nwith adversarial geometry and is 3x faster than registering point clouds to a\nprecomputed dataset of objects and indexing grasps. The Dex-Net 2.0 grasp\nplanner also has the highest success rate on a dataset of 10 novel rigid\nobjects and achieves 99% precision (one false positive out of 69 grasps\nclassified as robust) on a dataset of 40 novel household objects, some of which\nare articulated or deformable. Code, datasets, videos, and supplementary\nmaterial are available at this http URL .\n",
"title": "Dex-Net 2.0: Deep Learning to Plan Robust Grasps with Synthetic Point Clouds and Analytic Grasp Metrics"
}
| null | null | null | null | true | null |
11857
| null |
Default
| null | null |
null |
{
"abstract": " The mechanical behaviors of monolayer black phosphorene (MBP) are explored by\nmolecular dynamics (MD) simulations using reactive force field. It is revealed\nthat the temperature and strain rate have significant influence on mechanical\nbehaviors of MBP, and they are further weakened by SW (Stone-Wales) defects. In\ngeneral, the tensile strength for both of the pristine and SW defective MBP\ndecreases with the increase of temperature or decreasing of strain rate.\nSurprisingly, for relatively high temperature and low strain rate, phase\ntransition from the black phosphorene to a mixture of {\\beta}-phase ({\\beta}-P)\nand {\\gamma}-phase ({\\gamma}-P) is observed for the SW-2 defective MBP under\narmchair tension, while self-healing of the SW-2 defect is observed under\nzigzag tension. A deformation map of SW-2 defective MBP under armchair tension\nat different temperature and strain rate is established, which is useful for\nthe design of phosphorene allotropes by strain. The results presented herein\nyield useful insights for designing and tuning the structure, and the\nmechanical and physical properties of phosphorene.\n",
"title": "Effects of temperature and strain rate on mechanical behaviors of Stone-Wales defective monolayer black phosphorene"
}
| null | null | null | null | true | null |
11858
| null |
Default
| null | null |
null |
{
"abstract": " The Ward identities for the charge and heat currents are derived for\nparticle-particle and particle-hole pairs. They are the exact constraints on\nthe current-vertex functions imposed by conservation laws and should be\nsatisfied by consistent theories. While the Ward identity for the charge\ncurrent of electrons is well established, that for the heat current is not\nunderstood correctly. Thus the correct interpretation is presented. On this\nfirm basis the Ward identities for pairs are discussed. As the application of\nthe identity we criticize some inconsistent results in the studies of the\nsuperconducting fluctuation transport and the transport anomaly in the normal\nstate of high-Tc superconductors.\n",
"title": "Ward identities for charge and heat currents of particle-particle and particle-hole pairs"
}
| null | null | null | null | true | null |
11859
| null |
Default
| null | null |
null |
{
"abstract": " Short electron pulses are demonstrated to trigger and control magnetic\nexcitations, even at low electron current densities.\nWe show that the tangential magnetic field surrounding a picosecond electron\npulse can imprint topologically protected magnetic textures such as skyrmions\nin a sample with a residual Dzyaloshinskii-Moriya spin-orbital coupling.\nCharacteristics of the created excitations such as the topological charge can\nbe steered via the duration and the strength of the electron pulses. The study\npoints to a possible way for a spatio-temporally controlled generation of\nskyrmionic excitations.\n",
"title": "Ultrafast imprinting of topologically protected magnetic textures via pulsed electrons"
}
| null | null |
[
"Physics"
] | null | true | null |
11860
| null |
Validated
| null | null |
null |
{
"abstract": " Models that can simulate how environments change in response to actions can\nbe used by agents to plan and act efficiently. We improve on previous\nenvironment simulators from high-dimensional pixel observations by introducing\nrecurrent neural networks that are able to make temporally and spatially\ncoherent predictions for hundreds of time-steps into the future. We present an\nin-depth analysis of the factors affecting performance, providing the most\nextensive attempt to advance the understanding of the properties of these\nmodels. We address the issue of computationally inefficiency with a model that\ndoes not need to generate a high-dimensional image at each time-step. We show\nthat our approach can be used to improve exploration and is adaptable to many\ndiverse environments, namely 10 Atari games, a 3D car racing environment, and\ncomplex 3D mazes.\n",
"title": "Recurrent Environment Simulators"
}
| null | null | null | null | true | null |
11861
| null |
Default
| null | null |
null |
{
"abstract": " The Shockley-Queisser limit is one of the most fundamental results in the\nfield of photovoltaics. Based on the principle of detailed balance, it defines\nan upper limit for a single junction solar cell that uses an absorber material\nwith a specific band gap. Although methods exist that allow a solar cell to\nexceed the Shockley-Queisser limit, here we show that it is possible to exceed\nthe Shockley-Queisser limit without considering any of these additions. Merely\nby introducing an absorptivity that does not assume that every photon with an\nenergy above the band gap is absorbed, efficiencies above the Shockley-Queisser\nlimit are obtained. This is related to the fact that assuming optimal\nabsorption properties also maximizes the recombination current within the\ndetailed balance approach. We conclude that considering a finite thickness for\nthe absorber layer allows the efficiency to exceed the Shockley-Queisser limit,\nand that this is more likely to occur for materials with small band gaps.\n",
"title": "Exceeding the Shockley-Queisser limit within the detailed balance framework"
}
| null | null | null | null | true | null |
11862
| null |
Default
| null | null |
null |
{
"abstract": " In this communication we present a detailed study of the effect of chemical\ndisorder on the optical response of Ni$_{1-x}$Pt$_x$ (0.1$\\leq$ x $\\leq$0.75)\nand Ni$_{3(1-x)/3}$Pt$_x$ (0.1$\\leq$ x $\\leq$0.3). We shall propose a formalism\nwhich will combine a Kubo-Greenwood approach with a DFT based tight-binding\nlinear muffin-tin orbitals (TB-LMTO) basis and augmented space recursion (ASR)\ntechnique to explicitly incorporate the effect of disorder. We show that\nchemical disorder has a large impact on optical response of Ni-Pt systems. In\nordered Ni-Pt alloys, the optical conductivity peaks are sharp. But as we\nswitch on chemical disorder, the UV peak becomes broadened and its position as\na function of composition and disorder carries the signature of a phase\ntransition from NiPt to Ni$_3$Pt with decreasing Pt concentration.\nQuantitatively this agrees well with Massalski's Ni-Pt phase diagram\n\\cite{massal}. Both ordered NiPt and Ni$_3$Pt have an optical conductivity\ntransition at 4.12 eV. But disordered NiPt has an optical conductivity\ntransition at 3.93 eV. If we decrease the Pt content, it results a chemical\nphase transition from NiPt to Ni$_3$Pt and shifts the peak position by 1.67 eV\nto the ultraviolet range at 5.6 eV. There is a significant broadening of UV\npeak with increasing Pt content due to enhancement of 3d(Ni)-5d(Pt) bonding.\nChemical disorder enhances the optical response of NiPt alloys nearly one order\nof magnitude. Our study also shows the fragile magnetic effect on optical\nresponse of disordered Ni$_{1-x}$Pt$_x$ (0.4$<$ x $<$0.6) binary alloys. Our\ntheoretical predictions agree more than reasonably well with both earlier\nexperimental as well as theoretical investigations.\n",
"title": "Effect of disorder on the optical response of NiPt and Ni$_3$Pt alloys"
}
| null | null | null | null | true | null |
11863
| null |
Default
| null | null |
null |
{
"abstract": " Model selection on validation data is an essential step in machine learning.\nWhile the mixing of data between training and validation is considered taboo,\npractitioners often violate it to increase performance. Here, we offer a\nsimple, practical method for using the validation set for training, which\nallows for a continuous, controlled trade-off between performance and\noverfitting of model selection. We define the notion of\non-average-validation-stable algorithms as one in which using small portions of\nvalidation data for training does not overfit the model selection process. We\nthen prove that stable algorithms are also validation stable. Finally, we\ndemonstrate our method on the MNIST and CIFAR-10 datasets using stable\nalgorithms as well as state-of-the-art neural networks. Our results show\nsignificant increase in test performance with a minor trade-off in bias\nadmitted to the model selection process.\n",
"title": "Train on Validation: Squeezing the Data Lemon"
}
| null | null | null | null | true | null |
11864
| null |
Default
| null | null |
null |
{
"abstract": " Motivation: The scratch assay is a standard experimental protocol used to\ncharacterize cell migration. It can be used to identify genes that regulate\nmigration and evaluate the efficacy of potential drugs that inhibit cancer\ninvasion. In these experiments, a scratch is made on a cell monolayer and\nrecolonisation of the scratched region is imaged to quantify cell migration\nrates. A drawback of this methodology is the lack of its reproducibility\nresulting in irregular cell-free areas with crooked leading edges. Existing\nquantification methods deal poorly with such resulting irregularities present\nin the data. Results: We introduce a new quantification method that can analyse\nlow quality experimental data. By considering in-silico and in-vitro data, we\nshow that the method provides a more accurate statistical classification of the\nmigration rates than two established quantification methods. The application of\nthis method will enable the quantification of migration rates of scratch assay\ndata previously unsuitable for analysis. Availability and Implementation: The\nsource code and the implementation of the algorithm as a GUI along with an\nexample dataset and user instructions, are available in\nthis https URL.\nThe datasets are available in\nthis https URL.\n",
"title": "Local migration quantification method for scratch assays"
}
| null | null | null | null | true | null |
11865
| null |
Default
| null | null |
null |
{
"abstract": " Robust analysis of coauthorship networks is based on high quality data.\nHowever, ground-truth data are usually unavailable. Empirical data suffer\nseveral types of errors, a typical one of which is called merging error,\nidentifying different persons as one entity. Specific features of authors have\nbeen used to reduce these errors. We proposed a Bayesian model to calculate the\ninformation of any given features of authors. Based on the features, the model\ncan be utilized to calculate the rate of merging errors for entities.\nTherefore, the model helps to find informative features for detecting heavily\ncompromised entities. It has potential contributions to improving the quality\nof empirical data.\n",
"title": "Assessing the level of merging errors for coauthorship data: a Bayesian model"
}
| null | null |
[
"Computer Science"
] | null | true | null |
11866
| null |
Validated
| null | null |
null |
{
"abstract": " Introduction: Identification of blood-based metabolic changes might provide\nearly and easy-to-obtain biomarkers.\nMethods: We included 127 AD patients and 121 controls with\nCSF-biomarker-confirmed diagnosis (cut-off tau/A$\\beta_{42}$: 0.52). Mass\nspectrometry platforms determined the concentrations of 53 amine, 22 organic\nacid, 120 lipid, and 40 oxidative stress compounds. Multiple signatures were\nassessed: differential expression (nested linear models), classification\n(logistic regression), and regulatory (network extraction).\nResults: Twenty-six metabolites were differentially expressed. Metabolites\nimproved the classification performance of clinical variables from 74% to 79%.\nNetwork models identified 5 hubs of metabolic dysregulation: Tyrosine,\nglycylglycine, glutamine, lysophosphatic acid C18:2 and platelet activating\nfactor C16:0. The metabolite network for APOE $\\epsilon$4 negative AD patients\nwas less cohesive compared to the network for APOE $\\epsilon$4 positive AD\npatients.\nDiscussion: Multiple signatures point to various promising peripheral markers\nfor further validation. The network differences in AD patients according to\nAPOE genotype may reflect different pathways to AD.\n",
"title": "Blood-based metabolic signatures in Alzheimer's disease"
}
| null | null | null | null | true | null |
11867
| null |
Default
| null | null |
null |
{
"abstract": " This article considers the minimal non-zero (= indecomposable) solutions of\nthe linear congruence $1\\cdot x_1 + \\cdots + (m-1)\\cdot x_{m-1} \\equiv 0 \\pmod\nm$ for unknown non-negative integers $x_1, \\ldots, x_n$, and characterizes the\nsolutions that attain the Eggleton-Erdős bound. Furthermore it discusses\nthe asymptotic behaviour of the number of indecomposable solutions. The results\nhave direct interpretations in terms of zero-sum sequences and invariant\ntheory.\n",
"title": "The Indecomposable Solutions of Linear Congruences"
}
| null | null |
[
"Mathematics"
] | null | true | null |
11868
| null |
Validated
| null | null |
null |
{
"abstract": " Let $(A,\\Delta)$ be a weak multiplier Hopf algebra. It is a pair of a\nnon-degenerate algebra $A$, with or without identity, and a coproduct $\\Delta$\non $A$, satisfying certain properties. The main difference with multiplier Hopf\nalgebras is that now, the canonical maps $T_1$ and $T_2$ on $A\\otimes A$,\ndefined by $$T_1(a\\otimes b)=\\Delta(a)(1\\otimes b)\n\\qquad\\quad\\text{and}\\qquad\\quad T_2(c\\otimes a)=(c\\otimes 1)\\Delta(a),$$ are\nno longer assumed to be bijective. Also recall that a weak multiplier Hopf\nalgebra is called regular if its antipode is a bijective map from $A$ to\nitself.\nIn this paper, we introduce and study the notion of integrals on such regular\nweak multiplier Hopf algebras. A left integral is a non-zero linear functional\non $A$ that is left invariant (in an appropriate sense). Similarly for a right\nintegral. For a regular weak multiplier Hopf algebra $(A,\\Delta)$ with\n(sufficiently many) integrals, we construct the dual $(\\widehat\nA,\\widehat\\Delta)$. It is again a regular weak multiplier Hopf algebra with\n(sufficiently many) integrals. This duality extends the known duality of\nfinite-dimensional weak Hopf algebras to this more general case. It also\nextends the duality of multiplier Hopf algebras with integrals, the so-called\nalgebraic quantum groups. For this reason, we will sometimes call a regular\nweak multiplier Hopf algebra with enough integrals an algebraic quantum\ngroupoid.\nWe discuss the relation of our work with the work on duality for algebraic\nquantum groupoids by Timmermann.\nWe also illustrate this duality with a particular example in a separate\npaper. In this paper, we only mention the main definitions and results for this\nexample. However, we do consider the two natural weak multiplier Hopf algebras\nassociated with a groupoid in detail and show that they are dual to each other\nin the sense of the above duality.\n",
"title": "Weak multiplier Hopf algebras III. Integrals and duality"
}
| null | null | null | null | true | null |
11869
| null |
Default
| null | null |
null |
{
"abstract": " Recent advances in bandit tools and techniques for sequential learning are\nsteadily enabling new applications and are promising the resolution of a range\nof challenging related problems. We study the game tree search problem, where\nthe goal is to quickly identify the optimal move in a given game tree by\nsequentially sampling its stochastic payoffs. We develop new algorithms for\ntrees of arbitrary depth, that operate by summarizing all deeper levels of the\ntree into confidence intervals at depth one, and applying a best arm\nidentification procedure at the root. We prove new sample complexity guarantees\nwith a refined dependence on the problem instance. We show experimentally that\nour algorithms outperform existing elimination-based algorithms and match\nprevious special-purpose methods for depth-two trees.\n",
"title": "Monte-Carlo Tree Search by Best Arm Identification"
}
| null | null | null | null | true | null |
11870
| null |
Default
| null | null |
null |
{
"abstract": " Modern reinforcement learning algorithms reach super-human performance on\nmany board and video games, but they are sample inefficient, i.e. they\ntypically require significantly more playing experience than humans to reach an\nequal performance level. To improve sample efficiency, an agent may build a\nmodel of the environment and use planning methods to update its policy. In this\narticle we introduce Variational State Tabulation (VaST), which maps an\nenvironment with a high-dimensional state space (e.g. the space of visual\ninputs) to an abstract tabular model. Prioritized sweeping with small backups,\na highly efficient planning method, can then be used to update state-action\nvalues. We show how VaST can rapidly learn to maximize reward in tasks like 3D\nnavigation and efficiently adapt to sudden changes in rewards or transition\nprobabilities.\n",
"title": "Efficient Model-Based Deep Reinforcement Learning with Variational State Tabulation"
}
| null | null | null | null | true | null |
11871
| null |
Default
| null | null |
null |
{
"abstract": " The antiferromagnetic Ising chain in both transverse and longitudinal\nmagnetic fields is one of the paradigmatic models of a quantum phase\ntransition. The antiferromagnetic system exhibits a zero-temperature critical\nline separating an antiferromagnetic phase and a paramagnetic phase; the\ncritical line connects an integrable quantum critical point at zero\nlongitudinal field and a classical first-order transition point at zero\ntransverse field. Using a strong-disorder renormalization group method\nformulated as a tree tensor network, we study the zero-temperature phase of the\nquantum Ising chain with bond randomness. We introduce a new matrix product\noperator representation of high-order moments, which provides an efficient and\naccurate tool for determining quantum phase transitions via the Binder cumulant\nof the order parameter. Our results demonstrate an infinite-randomness quantum\ncritical point in zero longitudinal field accompanied by pronounced quantum\nGriffiths singularities, arising from rare ordered regions with anomalously\nslow fluctuations inside the paramagnetic phase. The strong Griffiths effects\nare signaled by a large dynamical exponent $z>1$, which characterizes a\npower-law density of low-energy states of the localized rare regions and\nbecomes infinite at the quantum critical point. Upon application of a\nlongitudinal field, the quantum phase transition between the paramagnetic phase\nand the antiferromagnetic phase is completely destroyed. Furthermore, quantum\nGriffiths effects are suppressed, showing $z<1$, when the dynamics of the rare\nregions is hampered by the longitudinal field.\n",
"title": "Griffiths Singularities in the Random Quantum Ising Antiferromagnet: A Tree Tensor Network Renormalization Group Study"
}
| null | null | null | null | true | null |
11872
| null |
Default
| null | null |
null |
{
"abstract": " We give a rigorous analysis of the statistical behavior of gradients in a\nrandomly initialized fully connected network N with ReLU activations. Our\nresults show that the empirical variance of the squares of the entries in the\ninput-output Jacobian of N is exponential in a simple architecture-dependent\nconstant beta, given by the sum of the reciprocals of the hidden layer widths.\nWhen beta is large, the gradients computed by N at initialization vary wildly.\nOur approach complements the mean field theory analysis of random networks.\nFrom this point of view, we rigorously compute finite width corrections to the\nstatistics of gradients at the edge of chaos.\n",
"title": "Which Neural Net Architectures Give Rise To Exploding and Vanishing Gradients?"
}
| null | null | null | null | true | null |
11873
| null |
Default
| null | null |
null |
{
"abstract": " The task of multi-step ahead prediction in language models is challenging\nconsidering the discrepancy between training and testing. At test time, a\nlanguage model is required to make predictions given past predictions as input,\ninstead of the past targets that are provided during training. This difference,\nknown as exposure bias, can lead to the compounding of errors along a generated\nsequence at test time.\nIn order to improve generalization in neural language models and address\ncompounding errors, we propose a curriculum learning based method that\ngradually changes an initially deterministic teacher policy to a gradually more\nstochastic policy, which we refer to as \\textit{Nearest-Neighbor Replacement\nSampling}. A chosen input at a given timestep is replaced with a sampled\nnearest neighbor of the past target with a truncated probability proportional\nto the cosine similarity between the original word and its top $k$ most similar\nwords. This allows the teacher to explore alternatives when the teacher\nprovides a sub-optimal policy or when the initial policy is difficult for the\nlearner to model. The proposed strategy is straightforward, online and requires\nlittle additional memory requirements. We report our main findings on two\nlanguage modelling benchmarks and find that the proposed approach performs\nparticularly well when used in conjunction with scheduled sampling, that too\nattempts to mitigate compounding errors in language models.\n",
"title": "Curriculum-Based Neighborhood Sampling For Sequence Prediction"
}
| null | null | null | null | true | null |
11874
| null |
Default
| null | null |
null |
{
"abstract": " A common approach for designing scalable algorithms for massive data sets is\nto distribute the computation across, say $k$, machines and process the data\nusing limited communication between them. A particularly appealing framework\nhere is the simultaneous communication model whereby each machine constructs a\nsmall representative summary of its own data and one obtains an\napproximate/exact solution from the union of the representative summaries. If\nthe representative summaries needed for a problem are small, then this results\nin a communication-efficient and round-optimal protocol. While many fundamental\ngraph problems admit efficient solutions in this model, two prominent problems\nare notably absent from the list of successes, namely, the maximum matching\nproblem and the minimum vertex cover problem. Indeed, it was shown recently\nthat for both these problems, even achieving a polylog$(n)$ approximation\nrequires essentially sending the entire input graph from each machine.\nThe main insight of our work is that the intractability of matching and\nvertex cover in the simultaneous communication model is inherently connected to\nan adversarial partitioning of the underlying graph across machines. We show\nthat when the underlying graph is randomly partitioned across machines, both\nthese problems admit randomized composable coresets of size $\\widetilde{O}(n)$\nthat yield an $\\widetilde{O}(1)$-approximate solution. This results in an\n$\\widetilde{O}(1)$-approximation simultaneous protocol for these problems with\n$\\widetilde{O}(nk)$ total communication when the input is randomly partitioned\nacross $k$ machines. We further prove the optimality of our results. Finally,\nby a standard application of composable coresets, our results also imply\nMapReduce algorithms with the same approximation guarantee in one or two rounds\nof communication\n",
"title": "Randomized Composable Coresets for Matching and Vertex Cover"
}
| null | null | null | null | true | null |
11875
| null |
Default
| null | null |
null |
{
"abstract": " In this paper we describe simode: Separable Integral Matching for Ordinary\nDifferential Equations. The statistical methodologies applied in the package\nfocus on several minimization procedures of an integral-matching criterion\nfunction, taking advantage of the mathematical structure of the differential\nequations like separability of parameters from equations. Application of\nintegral based methods to parameter estimation of ordinary differential\nequations was shown to yield more accurate and stable results comparing to\nderivative based ones. Linear features such as separability were shown to ease\noptimization and inference. We demonstrate the functionalities of the package\nusing various systems of ordinary differential equations.\n",
"title": "simode: R Package for statistical inference of ordinary differential equations using separable integral-matching"
}
| null | null |
[
"Statistics"
] | null | true | null |
11876
| null |
Validated
| null | null |
null |
{
"abstract": " We prove the following generalization of the classical Lichnerowicz vanishing\ntheorem: if $F$ is an oriented flat vector bundle over a closed spin manifold\n$M$ such that $TM$ carries a metric of positive scalar curvature, then\n$<\\widehat A(TM)e(F),[M]>=0$, where $e(F)$ is the Euler class of $F$.\n",
"title": "Positive scalar curvature and the Euler class"
}
| null | null | null | null | true | null |
11877
| null |
Default
| null | null |
null |
{
"abstract": " In this paper, we introduce the online service with delay problem. In this\nproblem, there are $n$ points in a metric space that issue service requests\nover time, and a server that serves these requests. The goal is to minimize the\nsum of distance traveled by the server and the total delay in serving the\nrequests. This problem models the fundamental tradeoff between batching\nrequests to improve locality and reducing delay to improve response time, that\nhas many applications in operations management, operating systems, logistics,\nsupply chain management, and scheduling.\nOur main result is to show a poly-logarithmic competitive ratio for the\nonline service with delay problem. This result is obtained by an algorithm that\nwe call the preemptive service algorithm. The salient feature of this algorithm\nis a process called preemptive service, which uses a novel combination of\n(recursive) time forwarding and spatial exploration on a metric space. We hope\nthis technique will be useful for related problems such as reordering buffer\nmanagement, online TSP, vehicle routing, etc. We also generalize our results to\n$k > 1$ servers.\n",
"title": "Online Service with Delay"
}
| null | null | null | null | true | null |
11878
| null |
Default
| null | null |
null |
{
"abstract": " The influence of superheat treatment on the microstructure and dynamic\nmechanical properties of A357 alloys has been investigated. The study of\nmicrostructure was performed by the optical microscope. Dynamic mechanical\nproperties (storage modulus, loss modulus, and damping capacity) were measured\nby the dynamic mechanical analyzer (DMA). Microstructure showed coarser and\nangular eutectic Si particles with larger {\\alpha}-Al dendrites in the\nnon-superheated A357 alloy. In contrast, finer and rounded eutectic Si\nparticles together with smaller and preferred oriented {\\alpha}-Al dendrites\nhave been observed in the superheated A357 alloy. Dynamic mechanical properties\nshowed an increasing trend of loss modulus and damping capacity meanwhile a\ndecreasing trend of storage modulus at elevated temperatures for superheated\nand non-superheated A357 alloys. The high damping capacity of superheated A357\nhas been ascribed to the grain boundary damping at elevated temperatures.\n",
"title": "Comparison of dynamic mechanical properties of non-superheated and superheated A357 alloys"
}
| null | null | null | null | true | null |
11879
| null |
Default
| null | null |
null |
{
"abstract": " This paper presents refinements to the execution-cache-memory performance\nmodel and a previously published power model for multicore processors. The\ncombination of both enables a very accurate prediction of performance and\nenergy consumption of contemporary multicore processors as a function of\nrelevant parameters such as number of active cores as well as core and Uncore\nfrequencies. Model validation is performed on the Sandy Bridge-EP and\nBroadwell-EP microarchitectures. Production-related variations in chip quality\nare demonstrated through a statistical analysis of the fit parameters obtained\non one hundred Broadwell-EP CPUs of the same model. Insights from the models\nare used to explain the performance- and energy-related behavior of the\nprocessors for scalable as well as saturating (i.e., memory-bound) codes. In\nthe process we demonstrate the models' capability to identify optimal operating\npoints with respect to highest performance, lowest energy-to-solution, and\nlowest energy-delay product and identify a set of best practices for\nenergy-efficient execution.\n",
"title": "On the accuracy and usefulness of analytic energy models for contemporary multicore processors"
}
| null | null | null | null | true | null |
11880
| null |
Default
| null | null |
null |
{
"abstract": " Within the standard framework of quasi-steady flight, this paper derives a\nspeed that realizes the maximal obtainable range per unit of fuel. If this\nspeed is chosen at each instant of a flight plan $h(x)$ giving altitude $h$ as\na function of distance $x$, a variational problem for finding an optimal $h(x)$\ncan be formulated and solved. It yields flight plans with maximal range, and\nthese turn out to consist of mainly three phases using the optimal speed:\nstarting with a climb at maximal continuous admissible thrust, ending with a\ncontinuous descent at idle thrust, and in between with a transition based on a\nsolution of the Euler-Lagrange equation for the variational problem. A similar\nvariational problem is derived and solved for speed-restricted flights, e.g. at\n250 KIAS below 10000 ft. In contrast to the literature, the approach of this\npaper does not need more than standard ordinary differential equations solving\nvariational problems to derive range-optimal trajectories. Various numerical\nexamplesbased on a Standard Business Jet are added for illustration.\n",
"title": "A Simple Solution for Maximum Range Flight"
}
| null | null |
[
"Mathematics"
] | null | true | null |
11881
| null |
Validated
| null | null |
null |
{
"abstract": " In this paper we are interested in the problem of learning an over-complete\nbasis and a methodology such that the reconstruction or inverse problem does\nnot need optimization. We analyze the optimality of the presented approaches,\ntheir link to popular already known techniques s.a. Artificial Neural\nNetworks,k-means or Oja's learning rule. Finally, we will see that one approach\nto reach the optimal dictionary is a factorial and hierarchical approach. The\nderived approach lead to a formulation of a Deep Oja Network. We present\nresults on different tasks and present the resulting very efficient learning\nalgorithm which brings a new vision on the training of deep nets. Finally, the\ntheoretical work shows that deep frameworks are one way to efficiently have\nover-complete (combinatorially large) dictionary yet allowing easy\nreconstruction. We thus present the Deep Residual Oja Network (DRON). We\ndemonstrate that a recursive deep approach working on the residuals allow\nexponential decrease of the error w.r.t. the depth.\n",
"title": "Multiscale Residual Mixture of PCA: Dynamic Dictionaries for Optimal Basis Learning"
}
| null | null | null | null | true | null |
11882
| null |
Default
| null | null |
null |
{
"abstract": " We study the categories governing infinity (wheeled) properads. The graphical\ncategory, which was already known to be generalized Reedy, is in fact an\nEilenberg-Zilber category. A minor alteration to the definition of the wheeled\ngraphical category allows us to show that it is a generalized Reedy category.\nFinally, we present model structures for Segal properads and Segal wheeled\nproperads.\n",
"title": "On factorizations of graphical maps"
}
| null | null | null | null | true | null |
11883
| null |
Default
| null | null |
null |
{
"abstract": " The raking-ratio method is a statistical and computational method which\nadjusts the empirical measure to match the true probability of sets in a finite\npartition. We study the asymptotic behavior of the raking-ratio empirical\nprocess indexed by a class of functions when the auxiliary information is given\nby the learning of the probability of sets in partitions from another sample\nlarger than the sample of the statistician. Under some metric entropy\nhypothesis and conditions on the size of the independent samples, we establish\nthe strong approximation of this process with estimated auxiliary information\nand show in particular that weak convergence is the same as the classical\nraking-ratio empirical process. We also give possible statistical applications\nof these results like strengthening the $Z$-test and the chi-square goodness of\nfit test.\n",
"title": "Raking-ratio empirical process with auxiliary information learning"
}
| null | null | null | null | true | null |
11884
| null |
Default
| null | null |
null |
{
"abstract": " Predicting the efficacy of a drug for a given individual, using\nhigh-dimensional genomic measurements, is at the core of precision medicine.\nHowever, identifying features on which to base the predictions remains a\nchallenge, especially when the sample size is small. Incorporating expert\nknowledge offers a promising alternative to improve a prediction model, but\ncollecting such knowledge is laborious to the expert if the number of candidate\nfeatures is very large. We introduce a probabilistic model that can incorporate\nexpert feedback about the impact of genomic measurements on the sensitivity of\na cancer cell for a given drug. We also present two methods to intelligently\ncollect this feedback from the expert, using experimental design and\nmulti-armed bandit models. In a multiple myeloma blood cancer data set (n=51),\nexpert knowledge decreased the prediction error by 8%. Furthermore, the\nintelligent approaches can be used to reduce the workload of feedback\ncollection to less than 30% on average compared to a naive approach.\n",
"title": "Improving drug sensitivity predictions in precision medicine through active expert knowledge elicitation"
}
| null | null | null | null | true | null |
11885
| null |
Default
| null | null |
null |
{
"abstract": " Vagueness is something everyone is familiar with. In fact, most people think\nthat vagueness is closely related to language and exists only there. However,\nvagueness is a property of the physical world. Quantum computers harness\nsuperposition and entanglement to perform their computational tasks. Both\nsuperposition and entanglement are vague processes. Thus quantum computers,\nwhich process exact data without \"exploiting\" vagueness, are actually vague\ncomputers.\n",
"title": "On Vague Computers"
}
| null | null |
[
"Computer Science"
] | null | true | null |
11886
| null |
Validated
| null | null |
null |
{
"abstract": " We present a unique application of OxRAM devices in CMOS Image Sensors (CIS)\nfor dynamic range (DR) improvement. We propose a modified 3T-APS (Active Pixel\nSensor) circuit that incorporates OxRAM in 1T-1R configuration. DR improvement\nis achieved by resistive compression of the pixel output signal through\nautonomous programming of OxRAM device resistance during exposure. We show that\nby carefully preconditioning the OxRAM resistance, pixel DR can be enhanced.\nDetailed impact of OxRAM SET-to-RESET and RESET-to-SET transitions on pixel DR\nis discussed. For experimental validation with specific OxRAM preprogrammed\nstates, a 4 Kb 10 nm thick HfOx (1T-1R) matrix was fabricated and\ncharacterized. Best case, relative pixel DR improvement of ~ 50 dB was obtained\nfor our design.\n",
"title": "Exploiting OxRAM Resistive Switching for Dynamic Range Improvement of CMOS Image Sensors"
}
| null | null | null | null | true | null |
11887
| null |
Default
| null | null |
null |
{
"abstract": " We investigate the Goos-Hanchen (G-H) shifts reflected and transmitted by a\nyttrium-iron-garnet (YIG) film for both normal and oblique incidence. It is\nfound that the nonreciprocity effect of the MO material does not only result in\na nonvanishing reflected shift at normal incidence, but also leads to a\nslab-thickness-independent term which breaks the symmetry between the reflected\nand transmitted shifts at oblique incidence. The asymptotic behaviors of the\nnormal-incidence reflected shift are obtained in the vicinity of two\ncharacteristic frequencies corresponding to a minimum reflectivity and a total\nreflection, respectively. Moreover, the coexistence of two types of\nnegative-reflected-shift (NRS) at oblique incidence is discussed. We show that\nthe reversal of the shifts from positive to negative values can be realized by\ntuning the magnitude of applied magnetic field, the frequency of incident wave\nand the slab thickness as well as the incident angle. In addition, we further\ninvestigate two special cases for practical purposes: the reflected shift with\na total reflection and the transmitted shift with a total transmission.\nNumerical simulations are also performed to verify our analytical results.\n",
"title": "Magnetic control of Goos-Hanchen shifts in a yttrium-iron-garnet film"
}
| null | null |
[
"Physics"
] | null | true | null |
11888
| null |
Validated
| null | null |
null |
{
"abstract": " We discuss the potential advantages of calculating the effective mass of\nquasiparticles in the interacting electron liquid from the low-temperature free\nenergy vis-a-vis the conventional approach, in which the effective mass is\nobtained from approximate calculations of the self-energy, or from a quantum\nMonte Carlo evaluation of the energy of a variational \"quasiparticle wave\nfunction\". While raw quantum Monte Carlo data are presently too sparse to allow\nfor an accurate determination of the effective mass, the values estimated by\nthis method are numerically close to the ones obtained in previous calculations\nusing diagrammatic many-body theory. In contrast to this, a recently published\nparametrization of quantum Monte Carlo data for the free energy of the\nhomogeneous electron liquid yields effective masses that considerably deviate\nfrom previous calculations and even change sign for low densities, reflecting\nan unphysical negative entropy. We suggest that this anomaly is related to the\ntreatment of the exchange energy at finite temperature.\n",
"title": "Effective mass of quasiparticles from thermodynamics"
}
| null | null | null | null | true | null |
11889
| null |
Default
| null | null |
null |
{
"abstract": " A signed network is a network with each link associated with a positive or\nnegative sign. Models for nodes interacting over such signed networks, where\ntwo different types of interactions take place along the positive and negative\nlinks, respectively, arise from various biological, social, political, and\neconomic systems. As modifications to the conventional DeGroot dynamics for\npositive links, two basic types of negative interactions along negative links,\nnamely the opposing rule and the repelling rule, have been proposed and studied\nin the literature. This paper reviews a few fundamental convergence results for\nsuch dynamics over deterministic or random signed networks under a unified\nalgebraic-graphical method. We show that a systematic tool of studying node\nstate evolution over signed networks can be obtained utilizing generalized\nPerron-Frobenius theory, graph theory, and elementary algebraic recursions.\n",
"title": "Dynamics over Signed Networks"
}
| null | null | null | null | true | null |
11890
| null |
Default
| null | null |
null |
{
"abstract": " The fastICA algorithm is a popular dimension reduction technique used to\nreveal patterns in data. Here we show that the approximations used in fastICA\ncan result in patterns not being successfully recognised. We demonstrate this\nproblem using a two-dimensional example where a clear structure is immediately\nvisible to the naked eye, but where the projection chosen by fastICA fails to\nreveal this structure. This implies that care is needed when applying fastICA.\nWe discuss how the problem arises and how it is intrinsically connected to the\napproximations that form the basis of the computational efficiency of fastICA.\n",
"title": "On the Estimation of Entropy in the FastICA Algorithm"
}
| null | null | null | null | true | null |
11891
| null |
Default
| null | null |
null |
{
"abstract": " As an emerging single elemental layered material with a low symmetry in-plane\ncrystal lattice, black phosphorus (BP) has attracted significant research\ninterest owing to its unique electronic and optoelectronic properties,\nincluding its widely tunable bandgap, polarization dependent photoresponse and\nhighly anisotropic in-plane charge transport. Despite extensive study of the\nsteady-state charge transport in BP, there has not been direct characterization\nand visualization of the hot carriers dynamics in BP immediately after\nphotoexcitation, which is crucial to understanding the performance of BP-based\noptoelectronic devices. Here we use the newly developed scanning ultrafast\nelectron microscopy (SUEM) to directly visualize the motion of photo-excited\nhot carriers on the surface of BP in both space and time. We observe highly\nanisotropic in-plane diffusion of hot holes, with a 15-times higher diffusivity\nalong the armchair (x-) direction than that along the zigzag (y-) direction.\nOur results provide direct evidence of anisotropic hot carrier transport in BP\nand demonstrate the capability of SUEM to resolve ultrafast hot carrier\ndynamics in layered two-dimensional materials.\n",
"title": "Spatial-Temporal Imaging of Anisotropic Photocarrier Dynamics in Black Phosphorus"
}
| null | null | null | null | true | null |
11892
| null |
Default
| null | null |
null |
{
"abstract": " Following Wigert, a great number of authors including Ramanujan, Gronwall,\nErdős, Ivić, Heppner, J. Knopfmacher, Nicolas, Schwarz, Wirsing,\nFreiman, Shiu et al. determined the maximal order of several multiplicative\nfunctions, generalizing Wigert's result \\[\\max_{n\\leq x} \\log d(n)= (\\log\n2+o(1))\\frac{\\log x}{\\log \\log x}.\\]\nOn the contrary, for many multiplicative functions, the maximal order of\niterations of the functions remains wide open. The case of the iterated divisor\nfunction was only recently solved, answering a question of Ramanujan (1915).\nHere, we determine the maximal order of $\\log f(f(n))$ for a class of\nmultiplicative functions $f$ which are related to the divisor function. As a\ncorollary, we apply this to the function counting representations as sums of\ntwo squares of non-negative integers, also known as $r_2(n)/4$, and obtain an\nasymptotic formula: \\[\\max_{n\\leq x} \\log f(f(n))= (c+o(1))\\frac{\\sqrt{\\log\nx}}{\\log \\log x},\\] with some explicitly given positive constant $c$.\n",
"title": "The maximal order of iterated multiplicative functions"
}
| null | null | null | null | true | null |
11893
| null |
Default
| null | null |
null |
{
"abstract": " This article extends bimetric formulations of massive gravity to make the\nmass of the graviton to depend on its environment. This minimal extension\noffers a novel way to reconcile massive gravity with local tests of general\nrelativity without invoking the Vainshtein mechanism. On cosmological scales,\nit is argued that the model is stable and that it circumvents the Higuchi\nbound, hence relaxing the constraints on the parameter space. Moreover, with\nthis extension the strong coupling scale is also environmentally dependent in\nsuch a way that it is kept sufficiently higher than the expansion rate all the\nway up to the very early universe, while the present graviton mass is low\nenough to be phenomenologically interesting. In this sense the extended\nbigravity theory serves as a partial UV completion of the standard bigravity\ntheory. This extension is very generic and robust and a simple specific example\nis described.\n",
"title": "Extending applicability of bimetric theory: chameleon bigravity"
}
| null | null | null | null | true | null |
11894
| null |
Default
| null | null |
null |
{
"abstract": " We analyze the dynamics of an online algorithm for independent component\nanalysis in the high-dimensional scaling limit. As the ambient dimension tends\nto infinity, and with proper time scaling, we show that the time-varying joint\nempirical measure of the target feature vector and the estimates provided by\nthe algorithm will converge weakly to a deterministic measured-valued process\nthat can be characterized as the unique solution of a nonlinear PDE. Numerical\nsolutions of this PDE, which involves two spatial variables and one time\nvariable, can be efficiently obtained. These solutions provide detailed\ninformation about the performance of the ICA algorithm, as many practical\nperformance metrics are functionals of the joint empirical measures. Numerical\nsimulations show that our asymptotic analysis is accurate even for moderate\ndimensions. In addition to providing a tool for understanding the performance\nof the algorithm, our PDE analysis also provides useful insight. In particular,\nin the high-dimensional limit, the original coupled dynamics associated with\nthe algorithm will be asymptotically \"decoupled\", with each coordinate\nindependently solving a 1-D effective minimization problem via stochastic\ngradient descent. Exploiting this insight to design new algorithms for\nachieving optimal trade-offs between computational and statistical efficiency\nmay prove an interesting line of future research.\n",
"title": "The Scaling Limit of High-Dimensional Online Independent Component Analysis"
}
| null | null | null | null | true | null |
11895
| null |
Default
| null | null |
null |
{
"abstract": " Integrated photonics is a leading platform for quantum technologies including\nnonclassical state generation \\cite{Vergyris:2016-35975:SRP,\nSolntsev:2014-31007:PRX, Silverstone:2014-104:NPHOT, Solntsev:2016:RPH},\ndemonstration of quantum computational complexity \\cite{Lamitral_NJP2016} and\nsecure quantum communications \\cite{Zhang:2014-130501:PRL}. As photonic\ncircuits grow in complexity, full quantum tomography becomes impractical, and\ntherefore an efficient method for their characterization\n\\cite{Lobino:2008-563:SCI, Rahimi-Keshari:2011-13006:NJP} is essential. Here we\npropose and demonstrate a fast, reliable method for reconstructing the\ntwo-photon state produced by an arbitrary quadratically nonlinear optical\ncircuit. By establishing a rigorous correspondence between the generated\nquantum state and classical sum-frequency generation measurements from laser\nlight, we overcome the limitations of previous approaches for lossy multimode\ndevices \\cite{Liscidini:2013-193602:PRL, Helt:2015-1460:OL}. We applied this\nprotocol to a multi-channel nonlinear waveguide network, and measured a\n99.28$\\pm$0.31\\% fidelity between classical and quantum characterization. This\ntechnique enables fast and precise evaluation of nonlinear quantum photonic\nnetworks, a crucial step towards complex, large-scale, device production.\n",
"title": "Direct characterization of a nonlinear photonic circuit's wave function with laser light"
}
| null | null | null | null | true | null |
11896
| null |
Default
| null | null |
null |
{
"abstract": " When comparing the average citation impact of research groups, universities\nand countries, field normalisation reduces the influence of discipline and\ntime. Confidence intervals for these indicators can help with attempts to infer\nwhether differences between sets of publications are due to chance factors.\nAlthough both bootstrapping and formulae have been proposed for these, their\naccuracy is unknown. In response, this article uses simulated data to\nsystematically compare the accuracy of confidence limits in the simplest\npossible case, a single field and year. The results suggest that the MNLCS\n(Mean Normalised Log-transformed Citation Score) confidence interval formula is\nconservative for large groups but almost always safe, whereas bootstrap MNLCS\nconfidence intervals tend to be accurate but can be unsafe for smaller world or\ngroup sample sizes. In contrast, bootstrap MNCS (Mean Normalised Citation\nScore) confidence intervals can be very unsafe, although their accuracy\nincreases with sample sizes.\n",
"title": "The Accuracy of Confidence Intervals for Field Normalised Indicators"
}
| null | null |
[
"Computer Science"
] | null | true | null |
11897
| null |
Validated
| null | null |
null |
{
"abstract": " Generalizations of classical theta functions are proposed that include any\neven number of analytic parameters for which conditions of quasi-periodicity\nare fulfilled and that are representations of extended Heisenberg group.\nDifferential equations for generalized theta functions and finite non-unitary\nrepresentations of extended Heisenberg group are presented so as other\nproperties and possible applications are pointed out such as a projective\nembedding of tori by means of generalized theta functions.\n",
"title": "Generalized Theta Functions. I"
}
| null | null |
[
"Physics"
] | null | true | null |
11898
| null |
Validated
| null | null |
null |
{
"abstract": " A challenge for molecular quantum dynamics (QD) calculations is the curse of\ndimensionality with respect to the nuclear degrees of freedom. A common\napproach that works especially well for fast reactive processes is to reduce\nthe dimensionality of the system to a few most relevant coordinates.\nIdentifying these can become a very difficult task, since they often are highly\nunintuitive. We present a machine learning approach that utilizes an\nautoencoder that is trained to find a low-dimensional representation of a set\nof molecular configurations. These configurations are generated by trajectory\ncalculations performed on the reactive molecular systems of interest. The\nresulting low-dimensional representation can be used to generate a potential\nenergy surface grid in the desired subspace. Using the G-matrix formalism to\ncalculate the kinetic energy operator, QD calculations can be carried out on\nthis grid. In addition to step-by-step instructions for the grid construction,\nwe present the application to a test system.\n",
"title": "Constructing grids for molecular quantum dynamics using an autoencoder"
}
| null | null | null | null | true | null |
11899
| null |
Default
| null | null |
null |
{
"abstract": " In this paper, we consider the problem of pursuit-evasion using multiple\nAutonomous Underwater Vehicles (AUVs) in a 3D water volume, with and without\nsimple obstacles. Pursuit-evasion is a well studied topic in robotics, but the\nresults are mostly set in 2D environments, using unlimited line of sight\nsensing. We propose an algorithm for range limited sensing in 3D environments\nthat captures a finite speed evader based on one single previous observation of\nits location. The pursuers are first moved to form a maximal cage formation,\nbased on their number and sensor ranges, containing all of the possible evader\nlocations. The cage is then shrunk until every part of that volume is sensed,\nthereby capturing the evader. The pursuers need only limited sensing range and\nlow bandwidth communication, making the algorithm well suited for an underwater\nenvironment.\n",
"title": "3D Pursuit-Evasion for AUVs"
}
| null | null | null | null | true | null |
11900
| null |
Default
| null | null |
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