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null | inputs
dict | prediction
null | prediction_agent
null | annotation
list | annotation_agent
null | multi_label
bool 1
class | explanation
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{
"abstract": " We give upper and lower bounds for the number of solutions of the equation\n$p(z)\\log|z|+q(z)=0$ with polynomials $p$ and $q$.\n",
"title": "On the number of solutions of some transcendental equations"
}
| null | null | null | null | true | null |
4901
| null |
Default
| null | null |
null |
{
"abstract": " A representation formula for the relaxation of integral energies\n$$(u,v)\\mapsto\\int_{\\Omega} f(x,u(x),v(x))\\,dx,$$ is obtained, where $f$\nsatisfies $p$-growth assumptions, $1<p<+\\infty$, and the fields $v$ are\nsubjected to space-dependent first order linear differential constraints in the\nframework of $\\mathscr{A}$-quasiconvexity with variable coefficients.\n",
"title": "Relaxation of p-growth integral functionals under space-dependent differential constraints"
}
| null | null |
[
"Mathematics"
] | null | true | null |
4902
| null |
Validated
| null | null |
null |
{
"abstract": " Stochastic optimization is key to efficient inversion in PDE-constrained\noptimization. Using 'simultaneous shots', or random superposition of source\nterms, works very well in simple acquisition geometries where all sources see\nall receivers, but this rarely occurs in practice. We develop an approach that\ninterpolates data to an ideal acquisition geometry while solving the inverse\nproblem using simultaneous shots. The approach is formulated as a joint inverse\nproblem, combining ideas from low-rank interpolation with full-waveform\ninversion. Results using synthetic experiments illustrate the flexibility and\nefficiency of the approach.\n",
"title": "Simultaneous shot inversion for nonuniform geometries using fast data interpolation"
}
| null | null |
[
"Statistics"
] | null | true | null |
4903
| null |
Validated
| null | null |
null |
{
"abstract": " In recent years self organised critical neuronal models have provided\ninsights regarding the origin of the experimentally observed avalanching\nbehaviour of neuronal systems. It has been shown that dynamical synapses, as a\nform of short-term plasticity, can cause critical neuronal dynamics. Whereas\nlong-term plasticity, such as hebbian or activity dependent plasticity, have a\ncrucial role in shaping the network structure and endowing neural systems with\nlearning abilities. In this work we provide a model which combines both\nplasticity mechanisms, acting on two different time-scales. The measured\navalanche statistics are compatible with experimental results for both the\navalanche size and duration distribution with biologically observed percentages\nof inhibitory neurons. The time-series of neuronal activity exhibits temporal\nbursts leading to 1/f decay in the power spectrum. The presence of long-term\nplasticity gives the system the ability to learn binary rules such as XOR,\nproviding the foundation of future research on more complicated tasks such as\npattern recognition.\n",
"title": "Critical neural networks with short and long term plasticity"
}
| null | null |
[
"Physics"
] | null | true | null |
4904
| null |
Validated
| null | null |
null |
{
"abstract": " Music, being a multifaceted stimulus evolving at multiple timescales,\nmodulates brain function in a manifold way that encompasses not only the\ndistinct stages of auditory perception but also higher cognitive processes like\nmemory and appraisal. Network theory is apparently a promising approach to\ndescribe the functional reorganization of brain oscillatory dynamics during\nmusic listening. However, the music induced changes have so far been examined\nwithin the functional boundaries of isolated brain rhythms. Using naturalistic\nmusic, we detected the functional segregation patterns associated with\ndifferent cortical rhythms, as these were reflected in the surface EEG\nmeasurements. The emerged structure was compared across frequency bands to\nquantify the interplay among rhythms. It was also contrasted against the\nstructure from the rest and noise listening conditions to reveal the specific\ncomponents stemming from music listening. Our methodology includes an efficient\ngraph-partitioning algorithm, which is further utilized for mining prototypical\nmodular patterns, and a novel algorithmic procedure for identifying switching\nnodes that consistently change module during music listening. Our results\nsuggest the multiplex character of the music-induced functional reorganization\nand particularly indicate the dependence between the networks reconstructed\nfrom the {\\delta} and {\\beta}H rhythms. This dependence is further justified\nwithin the framework of nested neural oscillations and fits perfectly within\nthe context of recently introduced cortical entrainment to music. Considering\nits computational efficiency, and in conjunction with the flexibility of in\nsitu electroencephalography, it may lead to novel assistive tools for real-life\napplications.\n",
"title": "Harnessing functional segregation across brain rhythms as a means to detect EEG oscillatory multiplexing during music listening"
}
| null | null | null | null | true | null |
4905
| null |
Default
| null | null |
null |
{
"abstract": " The purpose of this paper is to give some characterizations of the weight\nfunctions $w$ such that $Mw$ is in $A_{\\infty}$. We show that for those weights\nto be in $A_{\\infty}$ ensures to be in $A_{1}$. We give a criterion in terms of\nthe local maximal functions $m_{\\lambda}$ and we present a pair of\napplications, among them someone similar to the Coifman-Rochberg\ncharacterization of $A_{1}$ but using functions of the form $(f^{\\#})^{\\delta}$\nand $(m_{\\lambda}u)^{\\delta}$ instead of $(Mf)^{\\delta}$.\n",
"title": "Some characterizations of the preimage of $A_{\\infty}$ for the Hardy-Littlewood maximal operator and consequences"
}
| null | null | null | null | true | null |
4906
| null |
Default
| null | null |
null |
{
"abstract": " Low-mass M stars are plentiful in the Universe and often host small, rocky\nplanets detectable with the current instrumentation. Recently, seven small\nplanets have been discovered orbiting the ultracool dwarf\nTRAPPIST-1\\cite{Gillon16,Gillon17}. We examine the role of electromagnetic\ninduction heating of these planets, caused by the star's rotation and the\nplanet's orbital motion. If the stellar rotation and magnetic dipole axes are\ninclined with respect to each other, induction heating can melt the upper\nmantle and enormously increase volcanic activity, sometimes producing a magma\nocean below the planetary surface. We show that induction heating leads the\nthree innermost planets, one of which is in the habitable zone, to either\nevolve towards a molten mantle planet, or to experience increased outgassing\nand volcanic activity, while the four outermost planets remain mostly\nunaffected.\n",
"title": "Magma oceans and enhanced volcanism on TRAPPIST-1 planets due to induction heating"
}
| null | null | null | null | true | null |
4907
| null |
Default
| null | null |
null |
{
"abstract": " Due to their numerous advantages, formal proofs and proof assistants, such as\nCoq, are becoming increasingly popular. However, one disadvantage of using\nproof assistants is that the resulting proofs can sometimes be hard to read and\nunderstand, particularly for less-experienced users. To address this issue, we\nhave implemented a tool capable of generating natural language versions of Coq\nproofs called Coqatoo, which we present in this paper.\n",
"title": "Coqatoo: Generating Natural Language Versions of Coq Proofs"
}
| null | null | null | null | true | null |
4908
| null |
Default
| null | null |
null |
{
"abstract": " In this study, we explore peer-interaction effects in online networks on\nspeaking skill development. In particular, we present an evidence for gradual\nbuildup of skills in a small-group setting that has not been reported in the\nliterature. We introduce a novel dataset of six online communities consisting\nof 158 participants focusing on improving their speaking skills. They\nvideo-record speeches for 5 prompts in 10 days and exchange comments and\nperformance-ratings with their peers. We ask (i) whether the participants'\nratings are affected by their interaction patterns with peers, and (ii) whether\nthere is any gradual buildup of speaking skills in the communities towards\nhomogeneity. To analyze the data, we employ tools from the emerging field of\nGraph Signal Processing (GSP). GSP enjoys a distinction from Social Network\nAnalysis in that the latter is concerned primarily with the connection\nstructures of graphs, while the former studies signals on top of graphs. We\nstudy the performance ratings of the participants as graph signals atop\nunderlying interaction topologies. Total variation analysis of the graph\nsignals show that the participants' rating differences decrease with time\n(slope=-0.04, p<0.01), while average ratings increase (slope=0.07,\np<0.05)--thereby gradually building up the ratings towards community-wide\nhomogeneity. We provide evidence for peer-influence through a prediction\nformulation. Our consensus-based prediction model outperforms baseline\nnetwork-agnostic regression models by about 23% in predicting performance\nratings. This, in turn, shows that participants' ratings are affected by their\npeers' ratings and the associated interaction patterns, corroborating previous\nfindings. Then, we formulate a consensus-based diffusion model that captures\nthese observations of peer-influence from our analyses.\n",
"title": "Buildup of Speaking Skills in an Online Learning Community: A Network-Analytic Exploration"
}
| null | null |
[
"Computer Science"
] | null | true | null |
4909
| null |
Validated
| null | null |
null |
{
"abstract": " Some explanations to Kaldi's PLDA implementation to make formula derivation\neasier to catch.\n",
"title": "A Note on Kaldi's PLDA Implementation"
}
| null | null | null | null | true | null |
4910
| null |
Default
| null | null |
null |
{
"abstract": " The low-energy quasiparticles of Weyl semimetals are a condensed-matter\nrealization of the Weyl fermions introduced in relativistic field theory.\nChiral anomaly, the nonconservation of the chiral charge under parallel\nelectric and magnetic fields, is arguably the most important phenomenon of Weyl\nsemimetals and has been explained as an imbalance between the occupancies of\nthe gapless, zeroth Landau levels with opposite chiralities. This widely\naccepted picture has served as the basis for subsequent studies. Here we report\nthe breakdown of the chiral anomaly in Weyl semimetals in a strong magnetic\nfield based on ab initio calculations. A sizable energy gap that depends\nsensitively on the direction of the magnetic field may open up due to the\nmixing of the zeroth Landau levels associated with the opposite-chirality Weyl\npoints that are away from each other in the Brillouin zone. Our study provides\na theoretical framework for understanding a wide range of phenomena closely\nrelated to the chiral anomaly in topological semimetals, such as\nmagnetotransport, thermoelectric responses, and plasmons, to name a few.\n",
"title": "Breakdown of the Chiral Anomaly in Weyl Semimetals in a Strong Magnetic Field"
}
| null | null | null | null | true | null |
4911
| null |
Default
| null | null |
null |
{
"abstract": " In Chinese societies, superstition is of paramount importance, and vehicle\nlicense plates with desirable numbers can fetch very high prices in auctions.\nUnlike other valuable items, license plates are not allocated an estimated\nprice before auction. I propose that the task of predicting plate prices can be\nviewed as a natural language processing (NLP) task, as the value depends on the\nmeaning of each individual character on the plate and its semantics. I\nconstruct a deep recurrent neural network (RNN) to predict the prices of\nvehicle license plates in Hong Kong, based on the characters on a plate. I\ndemonstrate the importance of having a deep network and of retraining.\nEvaluated on 13 years of historical auction prices, the deep RNN outperforms\nprevious models by a significant margin.\n",
"title": "Predicting Auction Price of Vehicle License Plate with Deep Recurrent Neural Network"
}
| null | null | null | null | true | null |
4912
| null |
Default
| null | null |
null |
{
"abstract": " Magnetic field-induced giant modification of the probabilities of five\ntransitions of $5S_{1/2}, F_g=2 \\rightarrow 5P_{3/2}, F_e=4$ of $^{85}$Rb and\nthree transitions of $5S_{1/2}, F_g=1 \\rightarrow 5P_{3/2}, F_e=3$ of $^{87}$Rb\nforbidden by selection rules for zero magnetic field has been observed\nexperimentally and described theoretically for the first time. For the case of\nexcitation with circularly-polarized ($\\sigma^+$) laser radiation, the\nprobability of $F_g=2, ~m_F=-2 \\rightarrow F_e=4, ~m_F=-1$ transition becomes\nthe largest among the seventeen transitions of $^{85}$Rb $F_g=2 \\rightarrow\nF_e=1,2,3,4$ group, and the probability of $F_g=1,~m_F=-1 \\rightarrow\nF_e=3,~m_F=0$ transition becomes the largest among the nine transitions of\n$^{87}$Rb $F_g=1 \\rightarrow F_e=0,1,2,3$ group, in a wide range of magnetic\nfield 200 -- 1000 G. Complete frequency separation of individual Zeeman\ncomponents was obtained by implementation of derivative selective reflection\ntechnique with a 300 nm-thick nanocell filled with Rb, allowing formation of\nnarrow optical resonances. Possible applications are addressed. The theoretical\nmodel is perfectly consistent with the experimental results.\n",
"title": "Magnetic field--induced modification of selection rules for Rb D$_2$ line monitored by selective reflection from a vapor nanocell"
}
| null | null | null | null | true | null |
4913
| null |
Default
| null | null |
null |
{
"abstract": " In this work, we develop an adaptive, multivariate partitioning algorithm for\nsolving mixed-integer nonlinear programs (MINLP) with multi-linear terms to\nglobal optimality. This iterative algorithm primarily exploits the advantages\nof piecewise polyhedral relaxation approaches via disjunctive formulations to\nsolve MINLPs to global optimality in contrast to the conventional spatial\nbranch-and-bound approaches. In order to maintain relatively small-scale\nmixed-integer linear programs at every iteration of the algorithm, we\nadaptively partition the variable domains appearing in the multi-linear terms.\nWe also provide proofs on convergence guarantees of the proposed algorithm to a\nglobal solution. Further, we discuss a few algorithmic enhancements based on\nthe sequential bound-tightening procedure as a presolve step, where we observe\nthe importance of solving piecewise relaxations compared to basic convex\nrelaxations to speed-up the convergence of the algorithm to global optimality.\nWe demonstrate the effectiveness of our disjunctive formulations and the\nalgorithm on well-known benchmark problems (including Pooling and Blending\ninstances) from MINLPLib and compare with state-of-the-art global optimization\nsolvers. With this novel approach, we solve several large-scale instances which\nare, in some cases, intractable by the global optimization solver. We also\nshrink the best known optimality gap for one of the hard, generalized pooling\nproblem instance.\n",
"title": "An Adaptive, Multivariate Partitioning Algorithm for Global Optimization of Nonconvex Programs"
}
| null | null |
[
"Computer Science",
"Mathematics"
] | null | true | null |
4914
| null |
Validated
| null | null |
null |
{
"abstract": " We classify Drinfeld twists for the quantum Borel subalgebra u_q(b) in the\nFrobenius-Lusztig kernel u_q(g), where g is a simple Lie algebra over C and q\nan odd root of unity. More specifically, we show that alternating forms on the\ncharacter group of the group of grouplikes for u_q(b) generate all twists for\nu_q(b), under a certain algebraic group action. This implies a simple\nclassification of Hopf algebras whose categories of representations are tensor\nequivalent to that of u_q(b). We also show that cocycle twists for the\ncorresponding De Concini-Kac algebra are in bijection with alternating forms on\nthe aforementioned character group.\n",
"title": "Twists of quantum Borel algebras"
}
| null | null | null | null | true | null |
4915
| null |
Default
| null | null |
null |
{
"abstract": " In big data analysis for detecting rare and weak signals among $n$ features,\nsome grouping-test methods such as Higher Criticism test (HC), Berk-Jones test\n(B-J), and $\\phi$-divergence test share the similar asymptotical optimality\nwhen $n \\rightarrow \\infty$. However, in practical data analysis $n$ is\nfrequently small and moderately large at most. In order to properly apply these\noptimal tests and wisely choose them for practical studies, it is important to\nknow how to get the p-values and statistical power of them. To address this\nproblem in an even broader context, this paper provides analytical solutions\nfor a general family of goodness-of-fit (GOF) tests, which covers these optimal\ntests. For any given i.i.d. and continuous distributions of the input test\nstatistics of the $n$ features, both p-value and statistical power of such a\nGOF test can be calculated. By calculation we compared the finite-sample\nperformances of asymptotically optimal tests under the normal mixture\nalternative. Results show that HC is the best choice when signals are rare,\nwhile B-J is more robust over various signal patterns. In the application to a\nreal genome-wide association study, results illustrate that the p-value\ncalculation works well, and the optimal tests have potentials for detecting\nnovel disease genes with weak genetic effects. The calculations have been\nimplemented in an R package SetTest and published on the CRAN.\n",
"title": "Distributions and Statistical Power of Optimal Signal-Detection Methods In Finite Cases"
}
| null | null | null | null | true | null |
4916
| null |
Default
| null | null |
null |
{
"abstract": " The class of quasi-median graphs is a generalisation of median graphs, or\nequivalently of CAT(0) cube complexes. The purpose of this thesis is to\nintroduce these graphs in geometric group theory. In the first part of our\nwork, we extend the definition of hyperplanes from CAT(0) cube complexes, and\nwe show that the geometry of a quasi-median graph essentially reduces to the\ncombinatorics of its hyperplanes. In the second part, we exploit the specific\nstructure of the hyperplanes to state combination results. The main idea is\nthat if a group acts in a suitable way on a quasi-median graph so that\nclique-stabilisers satisfy some non-positively curved property $\\mathcal{P}$,\nthen the whole group must satisfy $\\mathcal{P}$ as well. The properties we are\ninterested in are mainly (relative) hyperbolicity, (equivariant)\n$\\ell^p$-compressions, CAT(0)-ness and cubicality. In the third part, we apply\nour general criteria to several classes of groups, including graph products,\nGuba and Sapir's diagram products, some wreath products, and some graphs of\ngroups. Graph products are our most natural examples, where the link between\nthe group and its quasi-median graph is particularly strong and explicit; in\nparticular, we are able to determine precisely when a graph product is\nrelatively hyperbolic.\n",
"title": "Cubical-like geometry of quasi-median graphs and applications to geometric group theory"
}
| null | null | null | null | true | null |
4917
| null |
Default
| null | null |
null |
{
"abstract": " We propose doubly nested network(DNNet) where all neurons represent their own\nsub-models that solve the same task. Every sub-model is nested both layer-wise\nand channel-wise. While nesting sub-models layer-wise is straight-forward with\ndeep-supervision as proposed in \\cite{xie2015holistically}, channel-wise\nnesting has not been explored in the literature to our best knowledge.\nChannel-wise nesting is non-trivial as neurons between consecutive layers are\nall connected to each other. In this work, we introduce a technique to solve\nthis problem by sorting channels topologically and connecting neurons\naccordingly. For the purpose, channel-causal convolutions are used. Slicing\ndoubly nested network gives a working sub-network. The most notable application\nof our proposed network structure with slicing operation is resource-efficient\ninference. At test time, computing resources such as time and memory available\nfor running the prediction algorithm can significantly vary across devices and\napplications. Given a budget constraint, we can slice the network accordingly\nand use a sub-model for inference within budget, requiring no additional\ncomputation such as training or fine-tuning after deployment. We demonstrate\nthe effectiveness of our approach in several practical scenarios of utilizing\navailable resource efficiently.\n",
"title": "Doubly Nested Network for Resource-Efficient Inference"
}
| null | null | null | null | true | null |
4918
| null |
Default
| null | null |
null |
{
"abstract": " Recently, there is a series of reports by Wang et al. on the\nsuperconductivity in K-doped p-terphenyl (KxC18H14) with the transition\ntemperatures range from 7 to 123 Kelvin. Identifying the structural and bonding\ncharacter is the key to understand the superconducting phases and the related\nproperties. Therefore we carried out an extensive study on the crystal\nstructures with different doping levels and investigate the thermodynamic\nstability, structural, electronic, and magnetic properties by the\nfirst-principles calculations. Our calculated structures capture most features\nof the experimentally observed X-ray diffraction patterns. The K doping\nconcentration is constrained to within the range of 2 and 3. The obtained\nformation energy indicates that the system at x = 2.5 is more stable. The\nstrong ionic bonding interaction is found in between K atoms and organic\nmolecules. The charge transfer accounts for the metallic feature of the doped\nmaterials. For a small amount of charge transferred, the tilting force between\nthe two successive benzenes drives the system to stabilize at the\nantiferromagnetic ground state, while the system exhibits non-magnetic behavior\nwith increasing charge transfer. The multiformity of band structures near the\nFermi level indicates that the driving force for superconductivity is\ncomplicated.\n",
"title": "Structural and bonding character of potassium-doped p-terphenyl superconductors"
}
| null | null | null | null | true | null |
4919
| null |
Default
| null | null |
null |
{
"abstract": " Research on numerical stability of difference equations has been quite\nintensive in the past century. The choice of difference schemes for the\nderivative terms in these equations contributes to a wide range of the\nstability analysis issues - one of which is how a chosen scheme may directly or\nindirectly contribute to such stability. In the present paper, how far the\nforward difference scheme for the time derivative in the wave equation\ninfluences the stability of the equation numerical solution, is particularly\ninvestigated. The stability analysis of the corresponding difference equation\ninvolving four schemes, namely Lax's, central, forward, and rearward\ndifferences, were carried out, and the resulting stability criteria were\ncompared. The results indicate that the instability of the solution of wave\nequation is not always due to the forward difference scheme for the time\nderivative. Rather, it is shown in this paper that the stability criterion is\nstill possible when the spatial derivative is represented by an appropriate\ndifference scheme. This sheds light on the degree of applicability of a\ndifference scheme for a hyperbolic equation.\n",
"title": "Influence of the Forward Difference Scheme for the Time Derivative on the Stability of Wave Equation Numerical Solution"
}
| null | null | null | null | true | null |
4920
| null |
Default
| null | null |
null |
{
"abstract": " For a division ring $D$, denote by $\\mathcal M_D$ the $D$-ring obtained as\nthe completion of the direct limit $\\varinjlim_n M_{2^n}(D)$ with respect to\nthe metric induced by its unique rank function. We prove that, for any\nultramatricial $D$-ring $\\mathcal B$ and any non-discrete extremal pseudo-rank\nfunction $N$ on $\\mathcal B$, there is an isomorphism of $D$-rings\n$\\overline{\\mathcal B} \\cong \\mathcal M_D$, where $\\overline{\\mathcal B}$\nstands for the completion of $\\mathcal B$ with respect to the pseudo-metric\ninduced by $N$. This generalizes a result of von Neumann. We also show a\ncorresponding uniqueness result for $*$-algebras over fields $F$ with positive\ndefinite involution, where the algebra $\\mathcal M_F$ is endowed with its\nnatural involution coming from the $*$-transpose involution on each of the\nfactors $M_{2^n}(F)$.\n",
"title": "Uniqueness of the von Neumann continuous factor"
}
| null | null |
[
"Mathematics"
] | null | true | null |
4921
| null |
Validated
| null | null |
null |
{
"abstract": " The paper develops a hybrid method for solving a system of\nadvection--diffusion equations in a bulk domain coupled to advection--diffusion\nequations on an embedded surface. A monotone nonlinear finite volume method for\nequations posed in the bulk is combined with a trace finite element method for\nequations posed on the surface. In our approach, the surface is not fitted by\nthe mesh and is allowed to cut through the background mesh in an arbitrary way.\nMoreover, a triangulation of the surface into regular shaped elements is not\nrequired. The background mesh is an octree grid with cubic cells. As an example\nof an application, we consider the modeling of contaminant transport in\nfractured porous media. One standard model leads to a coupled system of\nadvection--diffusion equations in a bulk (matrix) and along a surface\n(fracture). A series of numerical experiments with both steady and unsteady\nproblems and different embedded geometries illustrate the numerical properties\nof the hybrid approach. The method demonstrates great flexibility in handling\ncurvilinear or branching lower dimensional embedded structures.\n",
"title": "A hybrid finite volume -- finite element method for bulk--surface coupled problems"
}
| null | null | null | null | true | null |
4922
| null |
Default
| null | null |
null |
{
"abstract": " This work focuses on quantitative representation of transport in systems with\nquenched disorder. Explicit mapping of the quenched trap model to continuous\ntime random walk is presented. Linear temporal transformation: $t\\to\nt/\\Lambda^{1/\\alpha}$ for transient process on translationally invariant\nlattice, in the sub-diffusive regime, is sufficient for asymptotic mapping.\nExact form of the constant $\\Lambda^{1/\\alpha}$ is established. Disorder\naveraged position probability density function for quenched trap model is\nobtained and analytic expressions for the diffusion coefficient and drift are\nprovided.\n",
"title": "From Quenched Disorder to Continuous Time Random Walk"
}
| null | null | null | null | true | null |
4923
| null |
Default
| null | null |
null |
{
"abstract": " This paper presents a first-order {distributed continuous-time algorithm} for\ncomputing the least-squares solution to a linear equation over networks. Given\nthe uniqueness of the solution, with nonintegrable and diminishing step size,\nconvergence results are provided for fixed graphs. The exact rate of\nconvergence is also established for various types of step size choices falling\ninto that category. For the case where non-unique solutions exist, convergence\nto one such solution is proved for constantly connected switching graphs with\nsquare integrable step size, and for uniformly jointly connected switching\ngraphs under the boundedness assumption on system states. Validation of the\nresults and illustration of the impact of step size on the convergence speed\nare made using a few numerical examples.\n",
"title": "Network Flows that Solve Least Squares for Linear Equations"
}
| null | null | null | null | true | null |
4924
| null |
Default
| null | null |
null |
{
"abstract": " In the last few years, Model Driven Development (MDD), Component-based\nSoftware Development (CBSD), and context-oriented software have become\ninteresting alternatives for the design and construction of self-adaptive\nsoftware systems. In general, the ultimate goal of these technologies is to be\nable to reduce development costs and effort, while improving the modularity,\nflexibility, adaptability, and reliability of software systems. An analysis of\nthese technologies shows them all to include the principle of the separation of\nconcerns, and their further integration is a key factor to obtaining\nhigh-quality and self-adaptable software systems. Each technology identifies\ndifferent concerns and deals with them separately in order to specify the\ndesign of the self-adaptive applications, and, at the same time, support\nsoftware with adaptability and context-awareness. This research studies the\ndevelopment methodologies that employ the principles of model-driven\ndevelopment in building self-adaptive software systems. To this aim, this\narticle proposes an evaluation framework for analysing and evaluating the\nfeatures of model-driven approaches and their ability to support software with\nself-adaptability and dependability in highly dynamic contextual environment.\nSuch evaluation framework can facilitate the software developers on selecting a\ndevelopment methodology that suits their software requirements and reduces the\ndevelopment effort of building self-adaptive software systems. This study\nhighlights the major drawbacks of the propped model-driven approaches in the\nrelated works, and emphasise on considering the volatile aspects of\nself-adaptive software in the analysis, design and implementation phases of the\ndevelopment methodologies. In addition, we argue that the development\nmethodologies should leave the selection of modelling languages and modelling\ntools to the software developers.\n",
"title": "A Framework for Evaluating Model-Driven Self-adaptive Software Systems"
}
| null | null | null | null | true | null |
4925
| null |
Default
| null | null |
null |
{
"abstract": " In this article we study optimal control problems for systems that are affine\nwith respect to some of the control variables and nonlinear in relation to the\nothers. We consider finitely many equality and inequality constraints on the\ninitial and final values of the state. We investigate singular optimal\nsolutions for this class of problems, for which we obtain second order\nnecessary and sufficient conditions for weak optimality in integral form. We\nalso derive Goh pointwise necessary optimality conditions. We show an example\nto illustrate the results.\n",
"title": "Second order necessary and sufficient optimality conditions for singular solutions of partially-affine control problems"
}
| null | null | null | null | true | null |
4926
| null |
Default
| null | null |
null |
{
"abstract": " Bipartite Envy-Free Matching (BEFM) is a relaxation of perfect matching. In a\nbipartite graph with parts X and Y, a BEFM is a matching of some vertices in X\nto some vertices in Y, such that each unmatched vertex in X is not adjacent to\nany matched vertex in Y (so the unmatched vertices do not \"envy\" the matched\nones). The empty matching is always a BEFM. This paper presents sufficient and\nnecessary conditions for the existence of a non-empty BEFM. These conditions\nare based on cardinality of neighbor-sets, similarly to Hall's condition for\nthe existence of a perfect matching. The conditions can be verified in\npolynomial time, and in case they are satisfied, a non-empty BEFM can be found\nby a polynomial-time algorithm. The paper presents some applications of BEFM as\na subroutine in fair division algorithms.\n",
"title": "Bipartite Envy-Free Matching"
}
| null | null | null | null | true | null |
4927
| null |
Default
| null | null |
null |
{
"abstract": " Off-diagonal Aubry-André (AA) model has recently attracted a great deal\nof attention as they provide condensed matter realization of topological\nphases. We numerically study a generalized off-diagonal AA model with p-wave\nsuperfluid pairing in the presence of both commensurate and incommensurate\nhopping modulations. The phase diagram as functions of the modulation strength\nof incommensurate hopping and the strength of the p-wave pairing is obtained by\nusing the multifractal analysis. We show that with the appearance of the p-wave\npairing, the system exhibits mobility-edge phases and critical phases with\nvarious number of topologically protected zero-energy modes. Predicted\ntopological nature of these exotic phases can be realized in a cold atomic\nsystem of incommensurate bichromatic optical lattice with induced p-wave\nsuperfluid pairing by using a Raman laser in proximity to a molecular\nBose-Einstein condensation.\n",
"title": "Phase diagram of a generalized off-diagonal Aubry-André model with p-wave pairing"
}
| null | null | null | null | true | null |
4928
| null |
Default
| null | null |
null |
{
"abstract": " The analysis of networks affects the research of many real phenomena. The\ncomplex network structure can be viewed as a network's state at the time of the\nanalysis or as a result of the process through which the network arises.\nResearch activities focus on both and, thanks to them, we know not only many\nmeasurable properties of networks but also the essence of some phenomena that\noccur during the evolution of networks. One typical research area is the\nanalysis of co-authorship networks and their evolution. In our paper, the\nanalysis of one real-world co-authorship network and inspiration from existing\nmodels form the basis of the hypothesis from which we derive new 3-lambda\nnetwork model. This hypothesis works with the assumption that regular behavior\nof nodes revolves around an average. However, some anomalies may occur. The\n3-lambda model is stochastic and uses the three parameters associated with the\naverage behavior of the nodes. The growth of the network based on this model\nassumes that one step of the growth is an interaction in which both new and\nexisting nodes are participating. In the paper we present the results of the\nanalysis of a co-authorship network and formulate a hypothesis and a model\nbased on this hypothesis. Later in the paper, we examine the outputs from the\nnetwork generator based on the 3-lambda model and show that generated networks\nhave characteristics known from the environment of real-world networks.\n",
"title": "Around Average Behavior: 3-lambda Network Model"
}
| null | null | null | null | true | null |
4929
| null |
Default
| null | null |
null |
{
"abstract": " We investigate how star formation is spatially organized in the grand-design\nspiral NGC 1566 from deep HST photometry with the Legacy ExtraGalactic UV\nSurvey (LEGUS). Our contour-based clustering analysis reveals 890 distinct\nstellar conglomerations at various levels of significance. These star-forming\ncomplexes are organized in a hierarchical fashion with the larger congregations\nconsisting of smaller structures, which themselves fragment into even smaller\nand more compact stellar groupings. Their size distribution, covering a wide\nrange in length-scales, shows a power-law as expected from scale-free\nprocesses. We explain this shape with a simple \"fragmentation and enrichment\"\nmodel. The hierarchical morphology of the complexes is confirmed by their\nmass--size relation which can be represented by a power-law with a fractional\nexponent, analogous to that determined for fractal molecular clouds. The\nsurface stellar density distribution of the complexes shows a log-normal shape\nsimilar to that for supersonic non-gravitating turbulent gas. Between 50 and 65\nper cent of the recently-formed stars, as well as about 90 per cent of the\nyoung star clusters, are found inside the stellar complexes, located along the\nspiral arms. We find an age-difference between young stars inside the complexes\nand those in their direct vicinity in the arms of at least 10 Myr. This\ntimescale may relate to the minimum time for stellar evaporation, although we\ncannot exclude the in situ formation of stars. As expected, star formation\npreferentially occurs in spiral arms. Our findings reveal turbulent-driven\nhierarchical star formation along the arms of a grand-design galaxy.\n",
"title": "Hierarchical star formation across the grand design spiral NGC1566"
}
| null | null |
[
"Physics"
] | null | true | null |
4930
| null |
Validated
| null | null |
null |
{
"abstract": " Path planning in robotics often requires finding high-quality solutions to\ncontinuously valued and/or high-dimensional problems. These problems are\nchallenging and most planning algorithms instead solve simplified\napproximations. Popular approximations include graphs and random samples, as\nrespectively used by informed graph-based searches and anytime sampling-based\nplanners. Informed graph-based searches, such as A*, traditionally use\nheuristics to search a priori graphs in order of potential solution quality.\nThis makes their search efficient but leaves their performance dependent on the\nchosen approximation. If its resolution is too low then they may not find a\n(suitable) solution but if it is too high then they may take a prohibitively\nlong time to do so. Anytime sampling-based planners, such as RRT*,\ntraditionally use random sampling to approximate the problem domain\nincrementally. This allows them to increase resolution until a suitable\nsolution is found but makes their search dependent on the order of\napproximation. Arbitrary sequences of random samples expand the approximation\nin every direction and fill the problem domain but may be prohibitively\ninefficient at containing a solution. This paper unifies and extends these two\napproaches to develop Batch Informed Trees (BIT*), an informed, anytime\nsampling-based planner. BIT* solves continuous path planning problems\nefficiently by using sampling and heuristics to alternately approximate and\nsearch the problem domain. Its search is ordered by potential solution quality,\nas in A*, and its approximation improves indefinitely with additional\ncomputational time, as in RRT*. It is shown analytically to be almost-surely\nasymptotically optimal and experimentally to outperform existing sampling-based\nplanners, especially on high-dimensional planning problems.\n",
"title": "Informed Asymptotically Optimal Anytime Search"
}
| null | null | null | null | true | null |
4931
| null |
Default
| null | null |
null |
{
"abstract": " Let $P_k$ be a path, $C_k$ a cycle on $k$ vertices, and $K_{k,k}$ a complete\nbipartite graph with $k$ vertices on each side of the bipartition. We prove\nthat (1) for any integers $k, t>0$ and a graph $H$ there are finitely many\nsubgraph minimal graphs with no induced $P_k$ and $K_{t,t}$ that are not\n$H$-colorable and (2) for any integer $k>4$ there are finitely many subgraph\nminimal graphs with no induced $P_k$ that are not $C_{k-2}$-colorable.\nThe former generalizes the result of Hell and Huang [Complexity of coloring\ngraphs without paths and cycles, Discrete Appl. Math. 216: 211--232 (2017)] and\nthe latter extends a result of Bruce, Hoang, and Sawada [A certifying algorithm\nfor 3-colorability of $P_5$-Free Graphs, ISAAC 2009: 594--604]. Both our\nresults lead to polynomial-time certifying algorithms for the corresponding\ncoloring problems.\n",
"title": "Certifying coloring algorithms for graphs without long induced paths"
}
| null | null | null | null | true | null |
4932
| null |
Default
| null | null |
null |
{
"abstract": " We propose a general index model for survival data, which generalizes many\ncommonly used semiparametric survival models and belongs to the framework of\ndimension reduction. Using a combination of geometric approach in\nsemiparametrics and martingale treatment in survival data analysis, we devise\nestimation procedures that are feasible and do not require\ncovariate-independent censoring as assumed in many dimension reduction methods\nfor censored survival data. We establish the root-$n$ consistency and\nasymptotic normality of the proposed estimators and derive the most efficient\nestimator in this class for the general index model. Numerical experiments are\ncarried out to demonstrate the empirical performance of the proposed estimators\nand an application to an AIDS data further illustrates the usefulness of the\nwork.\n",
"title": "Efficient Estimation for Dimension Reduction with Censored Data"
}
| null | null | null | null | true | null |
4933
| null |
Default
| null | null |
null |
{
"abstract": " When dealing with the problem of simultaneously testing a large number of\nnull hypotheses, a natural testing strategy is to first reduce the number of\ntested hypotheses by some selection (screening or filtering) process, and then\nto simultaneously test the selected hypotheses. The main advantage of this\nstrategy is to greatly reduce the severe effect of high dimensions. However,\nthe first screening or selection stage must be properly accounted for in order\nto maintain some type of error control. In this paper, we will introduce a\nselection rule based on a selection statistic that is independent of the test\nstatistic when the tested hypothesis is true. Combining this selection rule and\nthe conventional Bonferroni procedure, we can develop a powerful and valid\ntwo-stage procedure. The introduced procedure has several nice properties: (i)\nit completely removes the selection effect; (ii) it reduces the multiplicity\neffect; (iii) it does not \"waste\" data while carrying out both selection and\ntesting. Asymptotic power analysis and simulation studies illustrate that this\nproposed method can provide higher power compared to usual multiple testing\nmethods while controlling the Type 1 error rate. Optimal selection thresholds\nare also derived based on our asymptotic analysis.\n",
"title": "Analysis of error control in large scale two-stage multiple hypothesis testing"
}
| null | null | null | null | true | null |
4934
| null |
Default
| null | null |
null |
{
"abstract": " Probability functions figure prominently in optimization problems of\nengineering. They may be nonsmooth even if all input data are smooth.This fact\nmotivates the consideration of subdifferentials for such typically just\ncontinuous functions. The aim of this paper is to provide subdifferential\nformulae in the case of Gaussian distributions for possibly\ninfinite-dimensional decision variables and nonsmooth (locally Lipschitzian)\ninput data. These formulae are based on the spheric-radial decomposition of\nGaussian random vectors on the one hand and on a cone of directions of moderate\ngrowth on the other. By successively adding additional hypotheses, conditions\nare satisfied under which the probability function is locally Lipschitzian or\neven differentiable.\n",
"title": "Subdifferential characterization of probability functions under Gaussian distribution"
}
| null | null |
[
"Mathematics"
] | null | true | null |
4935
| null |
Validated
| null | null |
null |
{
"abstract": " Predicting the next activity of a running process is an important aspect of\nprocess management. Recently, artificial neural networks, so called\ndeep-learning approaches, have been proposed to address this challenge. This\ndemo paper describes a software application that applies the Tensorflow\ndeep-learning framework to process prediction. The software application reads\nindustry-standard XES files for training and presents the user with an\neasy-to-use graphical user interface for both training and prediction. The\nsystem provides several improvements over earlier work. This demo paper focuses\non the software implementation and describes the architecture and user\ninterface.\n",
"title": "XES Tensorflow - Process Prediction using the Tensorflow Deep-Learning Framework"
}
| null | null |
[
"Computer Science"
] | null | true | null |
4936
| null |
Validated
| null | null |
null |
{
"abstract": " The high availability and scalability of weakly-consistent systems attracts\nsystem designers. Yet, writing correct application code for this type of\nsystems is difficult; even how to specify the intended behavior of such systems\nis still an open question. There has not been established any standard method\nto specify the intended dynamic behavior of a weakly consistent system. There\nexist specifications of various consistency models for distributed and\nconcurrent systems; and the semantics of replicated datatypes like CRDTs have\nbeen specified in axiomatic and operational models based on visibility\nrelations.\nIn this paper, we present a temporal logic, EPTL, that is tailored to specify\nproperties of weakly consistent systems. In contrast to LTL and CTL, EPTL takes\ninto account that operations of weakly consistent systems are in many cases not\nserializable and have to be treated respectively to capture the behavior. We\nembed our temporal logic in Isabelle/HOL and can thereby leverage strong\nsemi-automatic proving capabilities.\n",
"title": "EPTL - A temporal logic for weakly consistent systems"
}
| null | null | null | null | true | null |
4937
| null |
Default
| null | null |
null |
{
"abstract": " We investigate the initial-boundary value problem for the integrable spin-1\nGross-Pitaevskii (GP) equations with a 4x4 Lax pair on the half-line. The\nsolution of this system can be obtained in terms of the solution of a 4x4\nmatrix Riemann-Hilbert (RH) problem formulated in the complex k-plane. The\nrelevant jump matrices of the RH problem can be explicitly found using the two\nspectral functions s(k) and S(k), which can be defined by the initial data, the\nDirichlet-Neumann boundary data at x=0. The global relation is established\nbetween the two dependent spectral functions. The general mappings between\nDirichlet and Neumann boundary values are analyzed in terms of the global\nrelation.\n",
"title": "An initial-boundary value problem for the integrable spin-1 Gross-Pitaevskii equations with a 4x4 Lax pair on the half-line"
}
| null | null | null | null | true | null |
4938
| null |
Default
| null | null |
null |
{
"abstract": " This paper presents two visual trackers from the different paradigms of\nlearning and registration based tracking and evaluates their application in\nimage based visual servoing. They can track object motion with four degrees of\nfreedom (DoF) which, as we will show here, is sufficient for many fine\nmanipulation tasks. One of these trackers is a newly developed learning based\ntracker that relies on learning discriminative correlation filters while the\nother is a refinement of a recent 8 DoF RANSAC based tracker adapted with a new\nappearance model for tracking 4 DoF motion.\nBoth trackers are shown to provide superior performance to several state of\nthe art trackers on an existing dataset for manipulation tasks. Further, a new\ndataset with challenging sequences for fine manipulation tasks captured from\nrobot mounted eye-in-hand (EIH) cameras is also presented. These sequences have\na variety of challenges encountered during real tasks including jittery camera\nmovement, motion blur, drastic scale changes and partial occlusions.\nQuantitative and qualitative results on these sequences are used to show that\nthese two trackers are robust to failures while providing high precision that\nmakes them suitable for such fine manipulation tasks.\n",
"title": "4-DoF Tracking for Robot Fine Manipulation Tasks"
}
| null | null | null | null | true | null |
4939
| null |
Default
| null | null |
null |
{
"abstract": " Digital memcomputing machines (DMMs) are non-linear dynamical systems\ndesigned so that their equilibrium points are solutions of the Boolean problem\nthey solve. In a previous work [Chaos 27, 023107 (2017)] it was argued that\nwhen DMMs support solutions of the associated Boolean problem then strange\nattractors cannot coexist with such equilibria. In this work, we demonstrate\nsuch conjecture. In particular, we show that both topological transitivity and\nthe strongest property of topological mixing are inconsistent with the point\ndissipative property of DMMs when equilibrium points are present. This is true\nfor both the whole phase space and the global attractor. Absence of topological\ntransitivity is enough to imply absence of chaotic behavior. In a similar vein,\nwe prove that if DMMs do not have equilibrium points, the only attractors\npresent are invariant tori/periodic orbits with periods that may possibly\nincrease with system size (quasi-attractors).\n",
"title": "Absence of chaos in Digital Memcomputing Machines with solutions"
}
| null | null | null | null | true | null |
4940
| null |
Default
| null | null |
null |
{
"abstract": " We describe a broadly applicable experimental proposal to search for the\nviolation of local Lorentz invariance (LLI) with atomic systems. The new scheme\nuses dynamic decoupling and can be implemented in current atomic clocks\nexperiments, both with single ions and arrays of neutral atoms. Moreover, the\nscheme can be performed on systems with no optical transitions, and therefore\nit is also applicable to highly charged ions which exhibit particularly high\nsensitivity to Lorentz invariance violation. We show the results of an\nexperiment measuring the expected signal of this proposal using a two-ion\ncrystal of $^{88}$Sr$^+$ ions. We also carry out a systematic study of the\nsensitivity of highly charged ions to LLI to identify the best candidates for\nthe LLI tests.\n",
"title": "New ideas for tests of Lorentz invariance with atomic systems"
}
| null | null |
[
"Physics"
] | null | true | null |
4941
| null |
Validated
| null | null |
null |
{
"abstract": " We investigate 1D exoplanetary distributions using a novel analysis algorithm\nbased on the continuous wavelet transform. The analysis pipeline includes an\nestimation of the wavelet transform of the probability density function\n(p.d.f.) without pre-binning, use of optimized wavelets, a rigorous\nsignificance testing of the patterns revealed in the p.d.f., and an optimized\nminimum-noise reconstruction of the p.d.f. via matching pursuit iterations.\nIn the distribution of orbital periods, $P$, our analysis revealed a narrow\nsubfamily of exoplanets within the broad family of \"warm jupiters\", or massive\ngiants with $P\\gtrsim 300$~d, which are often deemed to be related with the\niceline accumulation in a protoplanetary disk. We detected a p.d.f. pattern\nthat represents an upturn followed by an overshooting peak spanning $P\\sim\n300-600$~d, right beyond the \"period valley\". It is separated from the other\nplanets by p.d.f. concavities from both sides. It has at least two-sigma\nsignificance.\nIn the distribution of planet radii, $R$, and using the California Kepler\nSurvey sample properly cleaned, we confirm the hints of a bimodality with two\npeaks about $R=1.3 R_\\oplus$ and $R=2.4 R_\\oplus$, and the \"evaporation valley\"\nbetween them. However, we obtain just a modest significance for this pattern,\ntwo-sigma only at the best. Besides, our follow-up application of the Hartigan\n& Hartigan dip test for unimodality returns $3$ per cent false alarm\nprobability (merely $2.2$-sigma significance), contrary to $0.14$ per cent (or\n$3.2$-sigma), as claimed by Fulton et al. (2017).\n",
"title": "Fine-resolution analysis of exoplanetary distributions by wavelets: hints of an overshooting iceline accumulation"
}
| null | null | null | null | true | null |
4942
| null |
Default
| null | null |
null |
{
"abstract": " Let $\\widetilde{\\mathcal M}=\\langle \\mathcal M, P\\rangle$ be an expansion of\nan o-minimal structure $\\mathcal M$ by a dense set $P\\subseteq M$, such that\nthree tameness conditions hold. We prove that the induced structure on $P$ by\n$\\mathcal M$ eliminates imaginaries. As a corollary, we obtain that every small\nset $X$ definable in $\\widetilde{\\mathcal M}$ can be definably embedded into\nsome $P^l$, uniformly in parameters, settling a question from [10]. We verify\nthe tameness conditions in three examples: dense pairs of real closed fields,\nexpansions of $\\mathcal M$ by a dense independent set, and expansions by a\ndense divisible multiplicative group with the Mann property. Along the way, we\npoint out a gap in the proof of a relevant elimination of imaginaries result in\nWencel [17]. The above results are in contrast to recent literature, as it is\nknown in general that $\\widetilde{\\mathcal M}$ does not eliminate imaginaries,\nand neither it nor the induced structure on $P$ admits definable Skolem\nfunctions.\n",
"title": "Small sets in dense pairs"
}
| null | null | null | null | true | null |
4943
| null |
Default
| null | null |
null |
{
"abstract": " Effective implementations of sampling-based probabilistic inference often\nrequire manually constructed, model-specific proposals. Inspired by recent\nprogresses in meta-learning for training learning agents that can generalize to\nunseen environments, we propose a meta-learning approach to building effective\nand generalizable MCMC proposals. We parametrize the proposal as a neural\nnetwork to provide fast approximations to block Gibbs conditionals. The learned\nneural proposals generalize to occurrences of common structural motifs across\ndifferent models, allowing for the construction of a library of learned\ninference primitives that can accelerate inference on unseen models with no\nmodel-specific training required. We explore several applications including\nopen-universe Gaussian mixture models, in which our learned proposals\noutperform a hand-tuned sampler, and a real-world named entity recognition\ntask, in which our sampler yields higher final F1 scores than classical\nsingle-site Gibbs sampling.\n",
"title": "Meta-Learning MCMC Proposals"
}
| null | null | null | null | true | null |
4944
| null |
Default
| null | null |
null |
{
"abstract": " Information distribution by electronic messages is a privileged means of\ntransmission for many businesses and individuals, often under the form of\nplain-text tables. As their number grows, it becomes necessary to use an\nalgorithm to extract text and numbers instead of a human. Usual methods are\nfocused on regular expressions or on a strict structure in the data, but are\nnot efficient when we have many variations, fuzzy structure or implicit labels.\nIn this paper we introduce SC2T, a totally self-supervised model for\nconstructing vector representations of tokens in semi-structured messages by\nusing characters and context levels that address these issues. It can then be\nused for an unsupervised labeling of tokens, or be the basis for a\nsemi-supervised information extraction system.\n",
"title": "Putting Self-Supervised Token Embedding on the Tables"
}
| null | null | null | null | true | null |
4945
| null |
Default
| null | null |
null |
{
"abstract": " The correlation between magnetic properties and microscopic structural\naspects in the diluted magnetic semiconductor Ge$_{1-x}$Mn$_{x}$Te is\ninvestigated by x-ray diffraction and magnetization as a function of the Mn\nconcentration $x$. The occurrence of high ferromagnetic-transition temperatures\nin the rhombohedrally distorted phase of slowly-cooled Ge$_{1-x}$Mn$_{x}$Te is\nshown to be directly correlated with the formation and coexistence of\nstrongly-distorted Mn-poor and weakly-distorted Mn-rich regions. It is\ndemonstrated that the weakly-distorted phase fraction is responsible for the\noccurrence of high-transition temperatures in Ge$_{1-x}$Mn$_{x}$Te. When the Mn\nconcentration becomes larger, the Mn-rich regions start to switch into the\nundistorted cubic structure, and the transition temperature is suppressed\nconcurrently. By identifying suitable annealing conditions, we successfully\nincreased the transition temperature to above 200 K for Mn concentrations close\nto the cubic phase. Structural data indicate that the weakly-distorted phase\nfraction can be restored at the expense of the cubic regions upon the\nenhancement of the transition temperature, clearly establishing the direct link\nbetween high-transition temperatures and the weakly-distorted Mn-rich phase\nfraction.\n",
"title": "Enhanced ferromagnetic transition temperature induced by a microscopic structural rearrangement in the diluted magnetic semiconductor Ge$_{1-x}$Mn$_{x}$Te"
}
| null | null | null | null | true | null |
4946
| null |
Default
| null | null |
null |
{
"abstract": " The Decodoku project seeks to let users get hands-on with cutting-edge\nquantum research through a set of simple puzzle games. The design of these\ngames is explicitly based on the problem of decoding qudit variants of surface\ncodes. This problem is presented such that it can be tackled by players with no\nprior knowledge of quantum information theory, or any other high-level physics\nor mathematics. Methods devised by the players to solve the puzzles can then\ndirectly be incorporated into decoding algorithms for quantum computation. In\nthis paper we give a brief overview of the novel decoding methods devised by\nplayers, and provide short postmortem for Decodoku v1.0-v4.1.\n",
"title": "Getting the public involved in Quantum Error Correction"
}
| null | null | null | null | true | null |
4947
| null |
Default
| null | null |
null |
{
"abstract": " Dynamic complexity is concerned with updating the output of a problem when\nthe input is slightly changed. We study the dynamic complexity of model\nchecking a fixed monadic second-order formula over evolving subgraphs of a\nfixed maximal graph having bounded tree-width; here the subgraph evolves by\nlosing or gaining edges (from the maximal graph). We show that this problem is\nin DynFO (with LOGSPACE precomputation), via a reduction to a Dyck reachability\nproblem on an acyclic automaton.\n",
"title": "Courcelle's Theorem Made Dynamic"
}
| null | null | null | null | true | null |
4948
| null |
Default
| null | null |
null |
{
"abstract": " Fractures are ubiquitous in the subsurface and strongly affect flow and\ndeformation. The physical shape of the fractures, they are long and thin\nobjects, puts strong limitations on how the effect of this dynamics can be\nincorporated into standard reservoir simulation tools. This paper reports the\ndevelopment of an open-source software framework, termed PorePy, which is aimed\nat simulation of flow and transport in three-dimensional fractured reservoirs,\nas well as deformation of the reservoir due to shearing along fracture and\nfault planes. Starting from a description of fractures as polygons embedded in\na 3D domain, PorePy provides semi-automatic gridding to construct a\ndiscrete-fracture-matrix model, which forms the basis for subsequent\nsimulations. PorePy allows for flow and transport in all lower-dimensional\nobjects, including planes (2D) representing fractures, and lines (1D) and\npoints (0D), representing fracture intersections. Interaction between processes\nin neighboring domains of different dimension is implemented as a sequence of\ncouplings of objects one dimension apart. This readily allows for handling of\ncomplex fracture geometries compared to capabilities of existing software. In\naddition to flow and transport, PorePy provides models for rock mechanics,\nporo-elasticity and coupling with fracture deformation models. The software is\nfully open, and can serve as a framework for transparency and reproducibility\nof simulations. We describe the design principles of PorePy from a user\nperspective, with focus on possibilities within gridding, covered physical\nprocesses and available discretizations. The power of the framework is\nillustrated with two sets of simulations; involving respectively coupled flow\nand transport in a fractured porous medium, and low-pressure stimulation of a\ngeothermal reservoir.\n",
"title": "PorePy: An Open-Source Simulation Tool for Flow and Transport in Deformable Fractured Rocks"
}
| null | null |
[
"Computer Science",
"Physics"
] | null | true | null |
4949
| null |
Validated
| null | null |
null |
{
"abstract": " This paper is concerned with the application of finite element methods to\nobtain solutions for steady fully developed second-grade flows in a curved pipe\nof circular cross-section and arbitrary curvature ratio, under a given axial\npressure gradient. The qualitative and quantitative behavior of the secondary\nflows is analyzed with respect to inertia and viscoelasticity.\n",
"title": "Second-grade fluids in curved pipes"
}
| null | null | null | null | true | null |
4950
| null |
Default
| null | null |
null |
{
"abstract": " Many audio signal processing methods are formulated in the time-frequency\n(T-F) domain which is obtained by the short-time Fourier transform (STFT). The\nproperty of STFT is fully characterized by window function, and thus designing\na better window is important for improving the performance of the processing\nespecially when a less redundant T-F representation is desirable. While many\nwindow functions have been proposed in the literature, they are designed to\nhave a good frequency response for analysis, which may not perform well in\nterms of signal processing. The window design must take the effect of the\nreconstruction (from the T-F domain into the time domain) into account for\nimproving the performance. In this paper, an optimization-based design method\nof a nearly tight window is proposed to obtain a window performing well for the\nT-F domain signal processing.\n",
"title": "Designing nearly tight window for improving time-frequency masking"
}
| null | null | null | null | true | null |
4951
| null |
Default
| null | null |
null |
{
"abstract": " Using stochastic gradient search and the optimal filter derivative, it is\npossible to perform recursive (i.e., online) maximum likelihood estimation in a\nnon-linear state-space model. As the optimal filter and its derivative are\nanalytically intractable for such a model, they need to be approximated\nnumerically. In [Poyiadjis, Doucet and Singh, Biometrika 2018], a recursive\nmaximum likelihood algorithm based on a particle approximation to the optimal\nfilter derivative has been proposed and studied through numerical simulations.\nHere, this algorithm and its asymptotic behavior are analyzed theoretically. We\nshow that the algorithm accurately estimates maxima to the underlying (average)\nlog-likelihood when the number of particles is sufficiently large. We also\nderive (relatively) tight bounds on the estimation error. The obtained results\nhold under (relatively) mild conditions and cover several classes of non-linear\nstate-space models met in practice.\n",
"title": "Asymptotic Properties of Recursive Maximum Likelihood Estimation in Non-Linear State-Space Models"
}
| null | null | null | null | true | null |
4952
| null |
Default
| null | null |
null |
{
"abstract": " For safe and efficient planning and control in autonomous driving, we need a\ndriving policy which can achieve desirable driving quality in long-term horizon\nwith guaranteed safety and feasibility. Optimization-based approaches, such as\nModel Predictive Control (MPC), can provide such optimal policies, but their\ncomputational complexity is generally unacceptable for real-time\nimplementation. To address this problem, we propose a fast integrated planning\nand control framework that combines learning- and optimization-based approaches\nin a two-layer hierarchical structure. The first layer, defined as the \"policy\nlayer\", is established by a neural network which learns the long-term optimal\ndriving policy generated by MPC. The second layer, called the \"execution\nlayer\", is a short-term optimization-based controller that tracks the reference\ntrajecotries given by the \"policy layer\" with guaranteed short-term safety and\nfeasibility. Moreover, with efficient and highly-representative features, a\nsmall-size neural network is sufficient in the \"policy layer\" to handle many\ncomplicated driving scenarios. This renders online imitation learning with\nDataset Aggregation (DAgger) so that the performance of the \"policy layer\" can\nbe improved rapidly and continuously online. Several exampled driving scenarios\nare demonstrated to verify the effectiveness and efficiency of the proposed\nframework.\n",
"title": "A Fast Integrated Planning and Control Framework for Autonomous Driving via Imitation Learning"
}
| null | null | null | null | true | null |
4953
| null |
Default
| null | null |
null |
{
"abstract": " Microservices architectures have become largely popular in the last years.\nHowever, we still lack empirical evidence about the use of microservices and\nthe practices followed by practitioners. Thereupon, in this paper, we report\nthe results of a survey with 122 professionals who work with microservices. We\nreport how the industry is using this architectural style and whether the\nperception of practitioners regarding the advantages and challenges of\nmicroservices is according to the literature.\n",
"title": "Microservices in Practice: A Survey Study"
}
| null | null |
[
"Computer Science"
] | null | true | null |
4954
| null |
Validated
| null | null |
null |
{
"abstract": " The application of high pressure can fundamentally modify the crystalline and\nelectronic structures of elements as well as their chemical reactivity, which\ncould lead to the formation of novel materials. Here, we explore the reactivity\nof lithium with sodium under high pressure, using a swarm structure searching\ntechniques combined with first-principles calculations, which identify a\nthermodynamically stable LiNa compound adopting an orthorhombic oP8 phase at\npressure above 355 GPa. The formation of LiNa may be a consequence of strong\nconcentration of electrons transfer from the lithium and the sodium atoms into\nthe interstitial sites, which also leads to opening a relatively wide band gap\nfor LiNa-op8. This is substantially different from the picture that share or\nexchange electrons in common compounds and alloys. In addition, lattice-dynamic\ncalculations indicate that LiNa-op8 remains dynamically stable when pressure\ndecompresses down to 70 GPa.\n",
"title": "Predicted novel insulating electride compound between alkali metals lithium and sodium under high pressure"
}
| null | null |
[
"Physics"
] | null | true | null |
4955
| null |
Validated
| null | null |
null |
{
"abstract": " Zero forcing and power domination are iterative processes on graphs where an\ninitial set of vertices are observed, and additional vertices become observed\nbased on some rules. In both cases, the goal is to eventually observe the\nentire graph using the fewest number of initial vertices. Chang et al.\nintroduced $k$-power domination in [Generalized power domination in graphs,\n{\\it Discrete Applied Math.} 160 (2012) 1691-1698] as a generalization of power\ndomination and standard graph domination. Independently, Amos et al. defined\n$k$-forcing in [Upper bounds on the $k$-forcing number of a graph, {\\it\nDiscrete Applied Math.} 181 (2015) 1-10] to generalize zero forcing. In this\npaper, we combine the study of $k$-forcing and $k$-power domination, providing\na new approach to analyze both processes. We give a relationship between the\n$k$-forcing and the $k$-power domination numbers of a graph that bounds one in\nterms of the other. We also obtain results using the contraction of subgraphs\nthat allow the parallel computation of $k$-forcing and $k$-power dominating\nsets.\n",
"title": "The relationship between $k$-forcing and $k$-power domination"
}
| null | null | null | null | true | null |
4956
| null |
Default
| null | null |
null |
{
"abstract": " We compare two important bases of an irreducible representation of the\nsymmetric group: the web basis and the Specht basis. The web basis has its\nroots in the Temperley-Lieb algebra and knot-theoretic considerations. The\nSpecht basis is a classic algebraic and combinatorial construction of symmetric\ngroup representations which arises in this context through the geometry of\nvarieties called Springer fibers. We describe a graph that encapsulates\ncombinatorial relations between each of these bases, prove that there is a\nunique way (up to scaling) to map the Specht basis into the web representation,\nand use this to recover a result of Garsia-McLarnan that the transition matrix\nbetween the Specht and web bases is upper-triangular with ones along the\ndiagonal. We then strengthen their result to prove vanishing of certain\nadditional entries unless a nesting condition on webs is satisfied. In fact we\nconjecture that the entries of the transition matrix are nonnegative and are\nnonzero precisely when certain directed paths exist in the web graph.\n",
"title": "The transition matrix between the Specht and web bases is unipotent with additional vanishing entries"
}
| null | null | null | null | true | null |
4957
| null |
Default
| null | null |
null |
{
"abstract": " In this chapter, we present a literature survey of an emerging, cutting-edge,\nand multi-disciplinary field of research at the intersection of Robotics and\nWireless Sensor Networks (WSN) which we refer to as Robotic Wireless Sensor\nNetworks (RWSN). We define a RWSN as an autonomous networked multi-robot system\nthat aims to achieve certain sensing goals while meeting and maintaining\ncertain communication performance requirements, through cooperative control,\nlearning and adaptation. While both of the component areas, i.e., Robotics and\nWSN, are very well-known and well-explored, there exist a whole set of new\nopportunities and research directions at the intersection of these two fields\nwhich are relatively or even completely unexplored. One such example would be\nthe use of a set of robotic routers to set up a temporary communication path\nbetween a sender and a receiver that uses the controlled mobility to the\nadvantage of packet routing. We find that there exist only a limited number of\narticles to be directly categorized as RWSN related works whereas there exist a\nrange of articles in the robotics and the WSN literature that are also relevant\nto this new field of research. To connect the dots, we first identify the core\nproblems and research trends related to RWSN such as connectivity,\nlocalization, routing, and robust flow of information. Next, we classify the\nexisting research on RWSN as well as the relevant state-of-the-arts from\nrobotics and WSN community according to the problems and trends identified in\nthe first step. Lastly, we analyze what is missing in the existing literature,\nand identify topics that require more research attention in the future.\n",
"title": "Robotic Wireless Sensor Networks"
}
| null | null | null | null | true | null |
4958
| null |
Default
| null | null |
null |
{
"abstract": " Mode connectivity is a recently introduced frame- work that empirically\nestablishes the connected- ness of minima by finding a high accuracy curve\nbetween two independently trained models. To investigate the limits of this\nsetup, we examine the efficacy of this technique in extreme cases where the\ninput models are trained or initialized differently. We find that the procedure\nis resilient to such changes. Given this finding, we propose using the\nframework for analyzing loss surfaces and training trajectories more generally,\nand in this direction, study SGD with cosine annealing and restarts (SGDR). We\nreport that while SGDR moves over barriers in its trajectory, propositions\nclaiming that it converges to and escapes from multiple local minima are not\nsubstantiated by our empirical results.\n",
"title": "Using Mode Connectivity for Loss Landscape Analysis"
}
| null | null | null | null | true | null |
4959
| null |
Default
| null | null |
null |
{
"abstract": " Lifelong learning is the problem of learning multiple consecutive tasks in a\nsequential manner where knowledge gained from previous tasks is retained and\nused for future learning. It is essential towards the development of\nintelligent machines that can adapt to their surroundings. In this work we\nfocus on a lifelong learning approach to generative modeling where we\ncontinuously incorporate newly observed distributions into our learnt model. We\ndo so through a student-teacher Variational Autoencoder architecture which\nallows us to learn and preserve all the distributions seen so far without the\nneed to retain the past data nor the past models. Through the introduction of a\nnovel cross-model regularizer, inspired by a Bayesian update rule, the student\nmodel leverages the information learnt by the teacher, which acts as a summary\nof everything seen till now. The regularizer has the additional benefit of\nreducing the effect of catastrophic interference that appears when we learn\nover sequences of distributions. We demonstrate its efficacy in learning\nsequentially observed distributions as well as its ability to learn a common\nlatent representation across a complex transfer learning scenario.\n",
"title": "Lifelong Generative Modeling"
}
| null | null | null | null | true | null |
4960
| null |
Default
| null | null |
null |
{
"abstract": " Floating-point arithmetic plays a central role in science, engineering, and\nfinance by enabling developers to approximate real arithmetic. To address\nnumerical issues in large floating-point applications, developers must identify\nroot causes, which is difficult because floating-point errors are generally\nnon-local, non-compositional, and non-uniform.\nThis paper presents Herbgrind, a tool to help developers identify and address\nroot causes in numerical code written in low-level C/C++ and Fortran. Herbgrind\ndynamically tracks dependencies between operations and program outputs to avoid\nfalse positives and abstracts erroneous computations to a simplified program\nfragment whose improvement can reduce output error. We perform several case\nstudies applying Herbgrind to large, expert-crafted numerical programs and show\nthat it scales to applications spanning hundreds of thousands of lines,\ncorrectly handling the low-level details of modern floating point hardware and\nmathematical libraries, and tracking error across function boundaries and\nthrough the heap.\n",
"title": "Finding Root Causes of Floating Point Error with Herbgrind"
}
| null | null | null | null | true | null |
4961
| null |
Default
| null | null |
null |
{
"abstract": " We have compiled a catalog of 903 candidates for type 1 quasars at redshifts\n3<z<5.5 selected among the X-ray sources of the serendipitous XMM-Newton survey\npresented in the 3XMM-DR4 catalog (the median X-ray flux is 5x10^{-15}\nerg/s/cm^2 the 0.5-2 keV energy band) and located at high Galactic latitudes\n>20 deg in Sloan Digital Sky Survey (SDSS) fields with a total area of about\n300 deg^2. Photometric SDSS data as well infrared 2MASS and WISE data were used\nto select the objects. We selected the point sources from the photometric SDSS\ncatalog with a magnitude error Delta z<0.2 and a color i-z<0.6 (to first\neliminate the M-type stars). For the selected sources, we have calculated the\ndependences chi^2(z) for various spectral templates from the library that we\ncompiled for these purposes using the EAZY software. Based on these data, we\nhave rejected the objects whose spectral energy distributions are better\ndescribed by the templates of stars at z=0 and obtained a sample of quasars\nwith photometric redshift estimates 2.75<zphot<5.5. The selection completeness\nof known quasars at z>3 in the investigated fields is shown to be about 80%.\nThe normalized median absolute deviation is 0.07, while the outlier fraction is\neta= 9. The number of objects per unit area in our sample exceeds the number of\nquasars in the spectroscopic SDSS sample at the same redshifts approximately by\na factor of 1.5. The subsequent spectroscopic testing of the redshifts of our\nselected candidates for quasars at 3<z<5.5 will allow the purity of this sample\nto be estimated more accurately.\n",
"title": "Catalog of Candidates for Quasars at 3 < z < 5.5 Selected among X-Ray Sources from the 3XMM-DR4 Survey of the XMM-Newton Observatory"
}
| null | null | null | null | true | null |
4962
| null |
Default
| null | null |
null |
{
"abstract": " We introduce a generalization of the celebrated Lovász theta number of a\ngraph to simplicial complexes of arbitrary dimension. Our generalization takes\nadvantage of real simplicial cohomology theory, in particular combinatorial\nLaplacians, and provides a semidefinite programming upper bound of the\nindependence number of a simplicial complex. We consider properties of the\ngraph theta number such as the relationship to Hoffman's ratio bound and to the\nchromatic number and study how they extend to higher dimensions. Like in the\ncase of graphs, the higher dimensional theta number can be extended to a\nhierarchy of semidefinite programming upper bounds reaching the independence\nnumber. We analyze the value of the theta number and of the hierarchy for dense\nrandom simplicial complexes.\n",
"title": "The Theta Number of Simplicial Complexes"
}
| null | null | null | null | true | null |
4963
| null |
Default
| null | null |
null |
{
"abstract": " Most multi-class classifiers make their prediction for a test sample by\nscoring the classes and selecting the one with the highest score. Analyzing\nthese prediction scores is useful to understand the classifier behavior and to\nassess its reliability. We present an interactive visualization that\nfacilitates per-class analysis of these scores. Our system, called Classilist,\nenables relating these scores to the classification correctness and to the\nunderlying samples and their features. We illustrate how such analysis reveals\nvarying behavior of different classifiers. Classilist is available for use\nonline, along with source code, video tutorials, and plugins for R, RapidMiner,\nand KNIME at this https URL.\n",
"title": "Prediction Scores as a Window into Classifier Behavior"
}
| null | null | null | null | true | null |
4964
| null |
Default
| null | null |
null |
{
"abstract": " We propose a new approach to the spectral theory of perturbed linear\noperators , in the case of a simple isolated eigenvalue. We obtain two kind of\nresults: \"radius bounds\" which ensure perturbation theory applies for\nperturbations up to an explicit size, and \"regularity bounds\" which control the\nvariations of eigendata to any order. Our method is based on the Implicit\nFunction Theorem and proceeds by establishing differential inequalities on two\nnatural quantities: the norm of the projection to the eigendirection, and the\nnorm of the reduced resolvent. We obtain completely explicit results without\nany assumption on the underlying Banach space. In companion articles, on the\none hand we apply the regularity bounds to Markov chains, obtaining\nnon-asymptotic concentration and Berry-Ess{é}en inequalities with explicit\nconstants, and on the other hand we apply the radius bounds to transfer\noperator of intermittent maps, obtaining explicit high-temperature regimes\nwhere a spectral gap occurs.\n",
"title": "Effective perturbation theory for linear operators"
}
| null | null |
[
"Mathematics"
] | null | true | null |
4965
| null |
Validated
| null | null |
null |
{
"abstract": " Consider random linear estimation with Gaussian measurement matrices and\nnoise. One can compute infinitesimal variations of the mutual information under\ninfinitesimal variations of the signal-to-noise ratio or of the measurement\nrate. We discuss how each variation is related to the minimum mean-square error\nand deduce that the two variations are directly connected through a very simple\nidentity. The main technical ingredient is a new interpolation method called\n\"sub-extensive interpolation method\". We use it to provide a new proof of an\nI-MMSE relation recently found by Reeves and Pfister [1] when the measurement\nrate is varied. Our proof makes it clear that this relation is intimately\nrelated to another I-MMSE relation also recently proved in [2]. One can\ndirectly verify that the identity relating the two types of variation of mutual\ninformation is indeed consistent with the one letter replica symmetric formula\nfor the mutual information, first derived by Tanaka [3] for binary signals, and\nrecently proved in more generality in [1,2,4,5] (by independent methods).\nHowever our proof is independent of any knowledge of Tanaka's formula.\n",
"title": "I-MMSE relations in random linear estimation and a sub-extensive interpolation method"
}
| null | null |
[
"Computer Science",
"Physics"
] | null | true | null |
4966
| null |
Validated
| null | null |
null |
{
"abstract": " We develop a class of algorithms, as variants of the stochastically\ncontrolled stochastic gradient (SCSG) methods (Lei and Jordan, 2016), for the\nsmooth non-convex finite-sum optimization problem. Assuming the smoothness of\neach component, the complexity of SCSG to reach a stationary point with\n$\\mathbb{E} \\|\\nabla f(x)\\|^{2}\\le \\epsilon$ is $O\\left (\\min\\{\\epsilon^{-5/3},\n\\epsilon^{-1}n^{2/3}\\}\\right)$, which strictly outperforms the stochastic\ngradient descent. Moreover, SCSG is never worse than the state-of-the-art\nmethods based on variance reduction and it significantly outperforms them when\nthe target accuracy is low. A similar acceleration is also achieved when the\nfunctions satisfy the Polyak-Lojasiewicz condition. Empirical experiments\ndemonstrate that SCSG outperforms stochastic gradient methods on training\nmulti-layers neural networks in terms of both training and validation loss.\n",
"title": "Non-convex Finite-Sum Optimization Via SCSG Methods"
}
| null | null | null | null | true | null |
4967
| null |
Default
| null | null |
null |
{
"abstract": " The hole diffusion length in n-InGaAs is extracted for two samples of\ndifferent doping concentrations using a set of long and thin diffused junction\ndiodes separated by various distances on the order of the diffusion length. The\nmethodology is described, including the ensuing analysis which yields diffusion\nlengths between 70 - 85 um at room temperature for doping concentrations in the\nrange of 5 - 9 x 10^15 cm-3. The analysis also provides insight into the\nminority carrier mobility which is a parameter not commonly reported in the\nliterature. Hole mobilities on the order of 500 - 750 cm2/Vs are reported for\nthe aforementioned doping range, which are comparable albeit longer than the\nmajority hole mobility for the same doping magnitude in p-InGaAs. A radiative\nrecombination coefficient of (0.5-0.2)x10^-10 cm^-3s^-1 is also extracted from\nthe ensuing analysis for an InGaAs thickness of 2.7 um. Preliminary evidence is\nalso given for both heavy and light hole diffusion. The dark current of\nInP/InGaAs p-i-n photodetectors with 25 and 15 um pitches are then calibrated\nto device simulations and correlated to the extracted diffusion lengths and\ndoping concentrations. An effective Shockley-Read-Hall lifetime of between\n90-200 us provides the best fit to the dark current of these structures.\n",
"title": "Minority carrier diffusion lengths and mobilities in low-doped n-InGaAs for focal plane array applications"
}
| null | null | null | null | true | null |
4968
| null |
Default
| null | null |
null |
{
"abstract": " Layered semi-convection is a possible candidate to explain Saturn's\nluminosity excess and the abnormally large radius of some hot Jupiters. In\ngiant planet interiors, it could lead to the creation of density staircases,\nwhich are convective layers separated by thin stably stratified interfaces. We\nstudy the propagation of internal waves in a region of layered semi-convection,\nwith the aim to predict energy transport by internal waves incident upon a\ndensity staircase. The goal is then to understand the resulting tidal\ndissipation when these waves are excited by other bodies such as moons in giant\nplanets systems. We use a local Cartesian analytical model, taking into account\nthe complete Coriolis acceleration at any latitude, thus generalizing previous\nworks. We find transmission of incident internal waves to be strongly affected\nby the presence of a density staircase, even if these waves are initially pure\ninertial waves (which are restored by the Coriolis acceleration). In\nparticular, low-frequency waves of all wavelengths are perfectly transmitted\nnear the critical latitude. Otherwise, short-wavelength waves are only\nefficiently transmitted if they are resonant with a free mode (interfacial\ngravity wave or short-wavelength inertial mode) of the staircase. In all other\ncases, waves are primarily reflected unless their wavelengths are longer than\nthe vertical extent of the entire staircase (not just a single step). We expect\nincident internal waves to be strongly affected by the presence of a density\nstaircase in a frequency-, latitude- and wavelength-dependent manner. First,\nthis could lead to new criteria to probe the interior of giant planets by\nseismology; and second, this may have important consequences for tidal\ndissipation and our understanding of the evolution of giant planet systems.\n",
"title": "Layered semi-convection and tides in giant planet interiors - I. Propagation of internal waves"
}
| null | null | null | null | true | null |
4969
| null |
Default
| null | null |
null |
{
"abstract": " We derive solvability conditions and closed-form solution for the Weber type\nintegral equation, related to the familiar Weber-Orr integral transforms and\nthe old Weber-Titchmarsh problem (posed in Proc. Lond. Math. Soc. 22 (2)\n(1924), pp.15, 16), recently solved by the author. Our method involves\nproperties of the inverse Mellin transform of integrable functions. The\nMellin-Parseval equality and some integrals, involving the Gauss hypergeometric\nfunction are used.\n",
"title": "A new Weber type integral equation related to the Weber-Titchmarsh problem"
}
| null | null | null | null | true | null |
4970
| null |
Default
| null | null |
null |
{
"abstract": " In this paper, we analyze the convergence of several discretize-then-optimize\nalgorithms, based on either a second-order or a fourth-order finite difference\ndiscretization, for solving elliptic PDE-constrained optimization or optimal\ncontrol problems. To ensure the convergence of a discretize-then-optimize\nalgorithm, one well-accepted criterion is to choose or redesign the\ndiscretization scheme such that the resultant discretize-then-optimize\nalgorithm commutes with the corresponding optimize-then-discretize algorithm.\nIn other words, both types of algorithms would give rise to exactly the same\ndiscrete optimality system. However, such an approach is not trivial. In this\nwork, by investigating a simple distributed elliptic optimal control problem,\nwe first show that enforcing such a stringent condition of commutative property\nis only sufficient but not necessary for achieving the desired convergence. We\nthen propose to add some suitable $H_1$ semi-norm penalty/regularization terms\nto recover the lost convergence due to the inconsistency caused by the loss of\ncommutativity. Numerical experiments are carried out to verify our theoretical\nanalysis and also validate the effectiveness of our proposed regularization\ntechniques.\n",
"title": "Non-commutative Discretize-then-Optimize Algorithms for Elliptic PDE-Constrained Optimal Control Problems"
}
| null | null | null | null | true | null |
4971
| null |
Default
| null | null |
null |
{
"abstract": " The paper evaluates three variants of the Gated Recurrent Unit (GRU) in\nrecurrent neural networks (RNN) by reducing parameters in the update and reset\ngates. We evaluate the three variant GRU models on MNIST and IMDB datasets and\nshow that these GRU-RNN variant models perform as well as the original GRU RNN\nmodel while reducing the computational expense.\n",
"title": "Gate-Variants of Gated Recurrent Unit (GRU) Neural Networks"
}
| null | null |
[
"Computer Science",
"Statistics"
] | null | true | null |
4972
| null |
Validated
| null | null |
null |
{
"abstract": " Let $(R, \\frak m)$ be a local ring and $M$ a finitely generated $R$-module.\nIt is shown that if $M$ is relative Cohen-Macaulay with respect to an ideal\n$\\frak a$ of $R$, then $\\text{Ann}_R(H_{\\mathfrak{a}}^{\\text{cd}(\\mathfrak{a},\nM)}(M))=\\text{Ann}_RM/L=\\text{Ann}_RM$ and\n$\\text{Ass}_R(R/\\text{Ann}_RM)\\subseteq \\{\\mathfrak{p} \\in \\text{Ass}_R\nM|\\,{\\rm cd}(\\mathfrak{a}, R/\\mathfrak{p})=\\text{cd}(\\mathfrak{a}, M)\\},$ where\n$L$ is the largest submodule of $M$ such that ${\\rm cd}(\\mathfrak{a}, L)< {\\rm\ncd}(\\mathfrak{a}, M)$. We also show that if $H^{\\dim M}_{\\mathfrak{a}}(M)=0$,\nthen $\\text{Att}_R(H^{\\dim M-1}_{\\mathfrak{a}}(M))= \\{\\mathfrak{p} \\in\n\\text{Supp} (M)|\\,{\\rm cd}(\\mathfrak{a}, R/\\mathfrak{p})=\\dim M-1\\},$ and so\nthe attached primes of $H^{\\dim M-1}_{\\mathfrak{a}}(M)$ depends only on\n$\\text{Supp} (M)$. Finally, we prove that if $M$ is an arbitrary module (not\nnecessarily finitely generated) over a Noetherian ring $R$ with ${\\rm\ncd}(\\mathfrak{a}, M)={\\rm cd}(\\mathfrak{a}, R/\\text{Ann}_RM)$, then\n$\\text{Att}_R(H^{{\\rm cd}(\\mathfrak{a},\nM)}_{\\mathfrak{a}}(M))\\subseteq\\{\\mathfrak{p} \\in V(\\text{Ann}_RM)|\\,{\\rm\ncd}(\\mathfrak{a}, R/\\mathfrak{p})={\\rm cd}(\\mathfrak{a}, M)\\}.$\nAs a consequence of this it is shown that if $\\dim M=\\dim R$, then\n$\\text{Att}_R(H^{\\dim M}_{\\mathfrak{a}}(M))\\subseteq\\{\\mathfrak{p} \\in\n\\text{Ass}_R M|\\,{\\rm cd}(\\mathfrak{a}, R/\\mathfrak{p})=\\dim M\\}.$\n",
"title": "Some results on the annihilators and attached primes of local cohomology modules"
}
| null | null |
[
"Mathematics"
] | null | true | null |
4973
| null |
Validated
| null | null |
null |
{
"abstract": " Spherical Gauss-Laguerre (SGL) basis functions, i.e., normalized functions of\nthe type $L_{n-l-1}^{(l + 1/2)}(r^2) r^{l} Y_{lm}(\\vartheta,\\varphi)$, $|m|\n\\leq l < n \\in \\mathbb{N}$, constitute an orthonormal polynomial basis of the\nspace $L^{2}$ on $\\mathbb{R}^{3}$ with radial Gaussian weight $\\exp(-r^{2})$.\nWe have recently described reliable fast Fourier transforms for the SGL basis\nfunctions. The main application of the SGL basis functions and our fast\nalgorithms is in solving certain three-dimensional rigid matching problems,\nwhere the center is prioritized over the periphery. For this purpose, so-called\nSGL translation matrix elements are required, which describe the spectral\nbehavior of the SGL basis functions under translations. In this paper, we\nderive a closed-form expression of these translation matrix elements, allowing\nfor a direct computation of these quantities in practice.\n",
"title": "Translation matrix elements for spherical Gauss-Laguerre basis functions"
}
| null | null |
[
"Mathematics"
] | null | true | null |
4974
| null |
Validated
| null | null |
null |
{
"abstract": " Inspired by the recent developments in the research of atom-photon quantum\ninterface and energy-time entanglement between single photon pulses, we propose\nto establish the concept of a special energy-time entanglement between a single\nphoton pulse and internal states of a single atom, which is analogous to the\nfrequency-bin entanglement between single photon pulses. We show that this type\nof entanglement arises naturally in the interaction between frequency-bin\nentangled single photon pulse pair and a single atom, via straightforward\natom-photon phase gate operations. We also discuss the properties of this type\nof entanglement and show a preliminary example of its potential application in\nquantum networking. Moreover, a quantum entanglement witness is constructed to\ndetect such entanglement from a reasonably large set of separable states.\n",
"title": "A theoretical analysis of extending frequency-bin entanglement from photon-photon to atom-photon hybrid systems"
}
| null | null | null | null | true | null |
4975
| null |
Default
| null | null |
null |
{
"abstract": " In this manuscript a method for developing novel filtering algorithms through\nthe parallel concatenation of two Bayesian filters is illustrated. Our\ndescription of this method, called turbo filtering, is based on a new graphical\nmodel; this allows us to efficiently describe both the processing accomplished\ninside each of the constituent filter and the interactions between them. This\nmodel is exploited to develop two new filtering algorithms for conditionally\nlinear Gaussian systems. Numerical results for a specific dynamic system\nevidence that such filters can achieve a better complexity-accuracy tradeoff\nthan marginalized particle filtering.\n",
"title": "Parallel Concatenation of Bayesian Filters: Turbo Filtering"
}
| null | null | null | null | true | null |
4976
| null |
Default
| null | null |
null |
{
"abstract": " Quantum phase slips (QPS) may produce non-equilibrium voltage fluctuations in\ncurrent-biased superconducting nanowires. Making use of the Keldysh technique\nand employing the phase-charge duality arguments we investigate such\nfluctuations within the four-point measurement scheme and demonstrate that shot\nnoise of the voltage detected in such nanowires may essentially depend on the\nparticular measurement setup. In long wires the shot noise power decreases with\nincreasing frequency $\\Omega$ and vanishes beyond a threshold value of $\\Omega$\nat $T \\to 0$\n",
"title": "Shot noise in ultrathin superconducting wires"
}
| null | null |
[
"Physics"
] | null | true | null |
4977
| null |
Validated
| null | null |
null |
{
"abstract": " We study different concepts of stability for modules over a finite\ndimensional algebra: linear stability, given by a \"central charge\", and\nnonlinear stability given by the wall-crossing sequence of a \"green path\". Two\nother concepts, finite Harder-Narasimhan stratification of the module category\nand maximal forward hom-orthogonal sequences of Schurian modules, which are\nalways equivalent to each other, are shown to be equivalent to nonlinear\nstability and to a maximal green sequence, defined using Fomin-Zelevinsky\nquiver mutation, in the case the algebra is hereditary.\nThis is the first of a series of three papers whose purpose is to determine\nall maximal green sequences of maximal length for quivers of affine type\n$\\tilde A$ and determine which are linear. The complete answer will be given in\nthe final paper [1].\n",
"title": "Linearity of stability conditions"
}
| null | null |
[
"Mathematics"
] | null | true | null |
4978
| null |
Validated
| null | null |
null |
{
"abstract": " In this paper, we show how using publicly available data streams and machine\nlearning algorithms one can develop practical data driven services with no\ninput from domain experts as a form of prior knowledge. We report the initial\nsteps toward development of a real estate portal in Switzerland. Based on\ncontinuous web crawling of publicly available real estate advertisements and\nusing building data from Open Street Map, we developed a system, where we\nroughly estimate the rental and sale price indexes of 1.7 million buildings\nacross the country. In addition to these rough estimates, we developed a web\nbased API for accurate automated valuation of rental prices of individual\nproperties and spatial sensitivity analysis of rental market. We tested several\nestablished function approximation methods against the test data to check the\nquality of the rental price estimations and based on our experiments, Random\nForest gives very reasonable results with the median absolute relative error of\n6.57 percent, which is comparable with the state of the art in the industry. We\nargue that while recently there have been successful cases of real estate\nportals, which are based on Big Data, majority of the existing solutions are\nexpensive, limited to certain users and mostly with non-transparent underlying\nsystems. As an alternative we discuss, how using the crawled data sets and\nother open data sets provided from different institutes it is easily possible\nto develop data driven services for spatial and temporal sensitivity analysis\nin the real estate market to be used for different stakeholders. We believe\nthat this kind of digital literacy can disrupt many other existing business\nconcepts across many domains.\n",
"title": "Urban Data Streams and Machine Learning: A Case of Swiss Real Estate Market"
}
| null | null | null | null | true | null |
4979
| null |
Default
| null | null |
null |
{
"abstract": " Enforcing open source licenses such as the GNU General Public License (GPL),\nanalyzing a binary for possible vulnerabilities, and code maintenance are all\nsituations where it is useful to be able to determine the source code\nprovenance of a binary. While previous work has either focused on computing\nbinary-to-binary similarity or source-to-source similarity, BinPro is the first\nwork we are aware of to tackle the problem of source-to-binary similarity.\nBinPro can match binaries with their source code even without knowing which\ncompiler was used to produce the binary, or what optimization level was used\nwith the compiler. To do this, BinPro utilizes machine learning to compute\noptimal code features for determining binary-to-source similarity and a static\nanalysis pipeline to extract and compute similarity based on those features.\nOur experiments show that on average BinPro computes a similarity of 81% for\nmatching binaries and source code of the same applications, and an average\nsimilarity of 25% for binaries and source code of similar but different\napplications. This shows that BinPro's similarity score is useful for\ndetermining if a binary was derived from a particular source code.\n",
"title": "BinPro: A Tool for Binary Source Code Provenance"
}
| null | null | null | null | true | null |
4980
| null |
Default
| null | null |
null |
{
"abstract": " The minimization of the length of syntactic dependencies is a\nwell-established principle of word order and the basis of a mathematical theory\nof word order. Here we complete that theory from the perspective of information\ntheory, adding a competing word order principle: the maximization of\npredictability of a target element. These two principles are in conflict: to\nmaximize the predictability of the head, the head should appear last, which\nmaximizes the costs with respect to dependency length minimization. The\nimplications of such a broad theoretical framework to understand the\noptimality, diversity and evolution of the six possible orderings of subject,\nobject and verb are reviewed.\n",
"title": "The placement of the head that maximizes predictability. An information theoretic approach"
}
| null | null |
[
"Computer Science",
"Physics"
] | null | true | null |
4981
| null |
Validated
| null | null |
null |
{
"abstract": " Consider the multivariate nonparametric regression model. It is shown that\nestimators based on sparsely connected deep neural networks with ReLU\nactivation function and properly chosen network architecture achieve the\nminimax rates of convergence (up to log n-factors) under a general composition\nassumption on the regression function. The framework includes many well-studied\nstructural constraints such as (generalized) additive models. While there is a\nlot of flexibility in the network architecture, the tuning parameter is the\nsparsity of the network. Specifically, we consider large networks with number\nof potential network parameters exceeding the sample size. The analysis gives\nsome insights why multilayer feedforward neural networks perform well in\npractice. Interestingly, the depth (number of layers) of the neural network\narchitectures plays an important role and our theory suggests that for\nnonparametric regression scaling the network depth with the logarithm of the\nsample size is natural. It is also shown that under the composition assumption\nwavelet estimators can only achieve suboptimal rates.\n",
"title": "Nonparametric regression using deep neural networks with ReLU activation function"
}
| null | null |
[
"Computer Science",
"Mathematics",
"Statistics"
] | null | true | null |
4982
| null |
Validated
| null | null |
null |
{
"abstract": " This paper presents an unsupervised method to learn a neural network, namely\nan explainer, to interpret a pre-trained convolutional neural network (CNN),\ni.e., the explainer uses interpretable visual concepts to explain features in\nmiddle conv-layers of a CNN. Given feature maps of a conv-layer of the CNN, the\nexplainer performs like an auto-encoder, which decomposes the feature maps into\nobject-part features. The object-part features are learned to reconstruct CNN\nfeatures without much loss of information. We can consider the disentangled\nrepresentations of object parts a paraphrase of CNN features, which help people\nunderstand the knowledge encoded by the CNN. More crucially, we learn the\nexplainer via knowledge distillation without using any annotations of object\nparts or textures for supervision. In experiments, our method was widely used\nto interpret features of different benchmark CNNs, and explainers significantly\nboosted the feature interpretability without hurting the discrimination power\nof the CNNs.\n",
"title": "Unsupervised Learning of Neural Networks to Explain Neural Networks (extended abstract)"
}
| null | null |
[
"Computer Science",
"Statistics"
] | null | true | null |
4983
| null |
Validated
| null | null |
null |
{
"abstract": " As virtual reality (VR) emerges as a mainstream platform, designers have\nstarted to experiment new interaction techniques to enhance the user\nexperience. This is a challenging task because designers not only strive to\nprovide designs with good performance but also carefully ensure not to disrupt\nusers' immersive experience. There is a dire need for a new evaluation tool\nthat extends beyond traditional quantitative measurements to assist designers\nin the design process. We propose an EEG-based experiment framework that\nevaluates interaction techniques in VR by measuring intentionally elicited\ncognitive conflict. Through the analysis of the feedback-related negativity\n(FRN) as well as other quantitative measurements, this framework allows\ndesigners to evaluate the effect of the variables of interest. We studied the\nframework by applying it to the fundamental task of 3D object selection using\ndirect 3D input, i.e. tracked hand in VR. The cognitive conflict is\nintentionally elicited by manipulating the selection radius of the target\nobject. Our first behavior experiment validated the framework in line with the\nfindings of conflict-induced behavior adjustments like those reported in other\nclassical psychology experiment paradigms. Our second EEG-based experiment\nexamines the effect of the appearance of virtual hands. We found that the\namplitude of FRN correlates with the level of realism of the virtual hands,\nwhich concurs with the Uncanny Valley theory.\n",
"title": "Measuring Cognitive Conflict in Virtual Reality with Feedback-Related Negativity"
}
| null | null |
[
"Computer Science"
] | null | true | null |
4984
| null |
Validated
| null | null |
null |
{
"abstract": " Extreme deformations of the DNA double helix attracted a lot of attention\nduring the past decades. Particularly, the determination of the persistence\nlength of DNA with extreme local disruptions, or kinks, has become a crucial\nproblem in the studies of many important biological processes. In this paper we\nreview an approach to calculate the persistence length of the double helix by\ntaking into account the formation of kinks of arbitrary configuration. The\nreviewed approach improves the Kratky--Porod model to determine the type and\nnature of kinks that occur in the double helix, by measuring a reduction of the\npersistence length of the kinkable DNA.\n",
"title": "Strong deformations of DNA: Effect on the persistence length"
}
| null | null |
[
"Quantitative Biology"
] | null | true | null |
4985
| null |
Validated
| null | null |
null |
{
"abstract": " Many real-world objects are designed by smooth curves, especially in the\ndomain of aerospace and ship, where aerodynamic shapes (e.g., airfoils) and\nhydrodynamic shapes (e.g., hulls) are designed. To facilitate the design\nprocess of those objects, we propose a deep learning based generative model\nthat can synthesize smooth curves. The model maps a low-dimensional latent\nrepresentation to a sequence of discrete points sampled from a rational\nBézier curve. We demonstrate the performance of our method in completing both\nsynthetic and real-world generative tasks. Results show that our method can\ngenerate diverse and realistic curves, while preserving consistent shape\nvariation in the latent space, which is favorable for latent space design\noptimization or design space exploration.\n",
"title": "BézierGAN: Automatic Generation of Smooth Curves from Interpretable Low-Dimensional Parameters"
}
| null | null | null | null | true | null |
4986
| null |
Default
| null | null |
null |
{
"abstract": " We use inelastic light scattering to study Sr$_{1-x}$Na$_x$Fe$_2$As$_2$\n($x\\approx0.34$), which exhibits a robust tetragonal magnetic phase that\nrestores the four-fold rotation symmetry inside the orthorhombic magnetic\nphase. With cooling, we observe splitting and recombination of an $E_g$ phonon\npeak upon entering the orthorhombic and tetragonal magnetic phases,\nrespectively, consistent with the reentrant phase behavior. Our electronic\nRaman data reveal a pronounced feature that is clearly associated with the\ntetragonal magnetic phase, suggesting the opening of an electronic gap. No\nphonon back-folding behavior can be detected above the noise level, which\nimplies that any lattice translation symmetry breaking in the tetragonal\nmagnetic phase must be very weak.\n",
"title": "Raman scattering study of tetragonal magnetic phase in Sr$_{1-x}$Na$_x$Fe$_2$As$_2$: structural symmetry and electronic gap"
}
| null | null | null | null | true | null |
4987
| null |
Default
| null | null |
null |
{
"abstract": " In this paper, we study the problem of learning a mixture of Gaussians with\nstreaming data: given a stream of $N$ points in $d$ dimensions generated by an\nunknown mixture of $k$ spherical Gaussians, the goal is to estimate the model\nparameters using a single pass over the data stream. We analyze a streaming\nversion of the popular Lloyd's heuristic and show that the algorithm estimates\nall the unknown centers of the component Gaussians accurately if they are\nsufficiently separated. Assuming each pair of centers are $C\\sigma$ distant\nwith $C=\\Omega((k\\log k)^{1/4}\\sigma)$ and where $\\sigma^2$ is the maximum\nvariance of any Gaussian component, we show that asymptotically the algorithm\nestimates the centers optimally (up to constants); our center separation\nrequirement matches the best known result for spherical Gaussians\n\\citep{vempalawang}. For finite samples, we show that a bias term based on the\ninitial estimate decreases at $O(1/{\\rm poly}(N))$ rate while variance\ndecreases at nearly optimal rate of $\\sigma^2 d/N$.\nOur analysis requires seeding the algorithm with a good initial estimate of\nthe true cluster centers for which we provide an online PCA based clustering\nalgorithm. Indeed, the asymptotic per-step time complexity of our algorithm is\nthe optimal $d\\cdot k$ while space complexity of our algorithm is $O(dk\\log\nk)$.\nIn addition to the bias and variance terms which tend to $0$, the\nhard-thresholding based updates of streaming Lloyd's algorithm is agnostic to\nthe data distribution and hence incurs an approximation error that cannot be\navoided. However, by using a streaming version of the classical\n(soft-thresholding-based) EM method that exploits the Gaussian distribution\nexplicitly, we show that for a mixture of two Gaussians the true means can be\nestimated consistently, with estimation error decreasing at nearly optimal\nrate, and tending to $0$ for $N\\rightarrow \\infty$.\n",
"title": "Learning Mixture of Gaussians with Streaming Data"
}
| null | null | null | null | true | null |
4988
| null |
Default
| null | null |
null |
{
"abstract": " We report on the detailed analysis of a gravitationally-lensed Y-band\ndropout, A2744_YD4, selected from deep Hubble Space Telescope imaging in the\nFrontier Field cluster Abell 2744. Band 7 observations with the Atacama Large\nMillimeter Array (ALMA) indicate the proximate detection of a significant 1mm\ncontinuum flux suggesting the presence of dust for a star-forming galaxy with a\nphotometric redshift of $z\\simeq8$. Deep X-SHOOTER spectra confirms the high\nredshift identity of A2744_YD4 via the detection of Lyman $\\alpha$ emission at\na redshift $z$=8.38. The association with the ALMA detection is confirmed by\nthe presence of [OIII] 88$\\mu$m emission at the same redshift. Although both\nemission features are only significant at the 4 $\\sigma$ level, we argue their\njoint detection and the positional coincidence with a high redshift dropout in\nthe HST images confirms the physical association. Analysis of the available\nphotometric data and the modest gravitational magnification ($\\mu\\simeq2$)\nindicates A2744_YD4 has a stellar mass of $\\sim$ 2$\\times$10$^9$ M$_{\\odot}$, a\nstar formation rate of $\\sim20$ M$_{\\odot}$/yr and a dust mass of\n$\\sim$6$\\times$10$^{6}$ M$_{\\odot}$. We discuss the implications of the\nformation of such a dust mass only $\\simeq$200 Myr after the onset of cosmic\nreionisation.\n",
"title": "Dust in the reionization era: ALMA observations of a $z$=8.38 Galaxy"
}
| null | null |
[
"Physics"
] | null | true | null |
4989
| null |
Validated
| null | null |
null |
{
"abstract": " In this paper, we present a novel method for rapid high-resolution range\nsensing using green-blue stripe pattern. We use green and blue for designing\nhigh-frequency stripe projection pattern. For accurate and reliable range\nrecovery, we identify the stripe patterns by our color-stripe segmentation and\nunwrapping algorithms. The experimental result for a naked human face shows the\neffectiveness of our method.\n",
"title": "Green-Blue Stripe Pattern for Range Sensing from a Single Image"
}
| null | null | null | null | true | null |
4990
| null |
Default
| null | null |
null |
{
"abstract": " We present a new autoencoder-type architecture that is trainable in an\nunsupervised mode, sustains both generation and inference, and has the quality\nof conditional and unconditional samples boosted by adversarial learning.\nUnlike previous hybrids of autoencoders and adversarial networks, the\nadversarial game in our approach is set up directly between the encoder and the\ngenerator, and no external mappings are trained in the process of learning. The\ngame objective compares the divergences of each of the real and the generated\ndata distributions with the prior distribution in the latent space. We show\nthat direct generator-vs-encoder game leads to a tight coupling of the two\ncomponents, resulting in samples and reconstructions of a comparable quality to\nsome recently-proposed more complex architectures.\n",
"title": "It Takes (Only) Two: Adversarial Generator-Encoder Networks"
}
| null | null |
[
"Computer Science",
"Statistics"
] | null | true | null |
4991
| null |
Validated
| null | null |
null |
{
"abstract": " Boundary plasma physics plays an important role in tokamak confinement, but\nis difficult to simulate in a gyrokinetic code due to the scale-inseparable\nnonlocal multi-physics in magnetic separatrix and open magnetic field geometry.\nNeutral particles are also an important part of the boundary plasma physics. In\nthe present paper, noble electrostatic gyrokinetic techniques to simulate the\nflux-driven, low-beta electrostatic boundary plasma is reported. Gyrokinetic\nions and drift-kinetic electrons are utilized without scale-separation between\nthe neoclassical and turbulence dynamics. It is found that the nonlinear\nintermittent turbulence is a natural gyrokinetic phenomenon in the boundary\nplasma in the vicinity of the magnetic separatrix surface and in the scrape-off\nlayer.\n",
"title": "Electrostatic gyrokinetic simulation of global tokamak boundary plasma and the generation of nonlinear intermittent turbulence"
}
| null | null | null | null | true | null |
4992
| null |
Default
| null | null |
null |
{
"abstract": " Hyperbolic systems of PDEs can be solved to arbitrary orders of accuracy by\nusing the ADER Finite Volume method. These PDE systems may be non-conservative\nand non-homogeneous, and contain stiff source terms. ADER-FV requires a\nspatio-temporal polynomial reconstruction of the data in each spacetime cell,\nat each time step. This reconstruction is obtained as the root of a nonlinear\nsystem, resulting from the use of a Galerkin method. It was proved in Jackson\n[7] that for traditional choices of basis polynomials, the eigenvalues of\ncertain matrices appearing in these nonlinear systems are always 0, regardless\nof the number of spatial dimensions of the PDEs or the chosen order of accuracy\nof the ADER-FV method. This guarantees fast convergence to the Galerkin root\nfor certain classes of PDEs.\nIn Montecinos and Balsara [9] a new, more efficient class of basis\npolynomials for the one-dimensional ADER-FV method was presented. This new\nclass of basis polynomials, originally presented for conservative systems, is\nextended to multidimensional, non-conservative systems here, and the\ncorresponding property regarding the eigenvalues of the Galerkin matrices is\nproved.\n",
"title": "The Montecinos-Balsara ADER-FV Polynomial Basis: Convergence Properties & Extension to Non-Conservative Multidimensional Systems"
}
| null | null | null | null | true | null |
4993
| null |
Default
| null | null |
null |
{
"abstract": " We prove a reducibility result for a quantum harmonic oscillator in arbitrary\ndimensions with arbitrary frequencies perturbed by a linear operator which is a\npolynomial of degree two in $x_j$, $-i \\partial_j$ with coefficients which\ndepend quasiperiodically on time.\n",
"title": "Reducibility of the Quantum Harmonic Oscillator in $d$-dimensions with Polynomial Time Dependent Perturbation"
}
| null | null | null | null | true | null |
4994
| null |
Default
| null | null |
null |
{
"abstract": " The adaptive classification of the interference covariance matrix structure\nfor radar signal processing applications is addressed in this paper. This\nrepresents a key issue because many detection architectures are synthesized\nassuming a specific covariance structure which may not necessarily coincide\nwith the actual one due to the joint action of the system and environment\nuncertainties. The considered classification problem is cast in terms of a\nmultiple hypotheses test with some nested alternatives and the theory of Model\nOrder Selection (MOS) is exploited to devise suitable decision rules. Several\nMOS techniques, such as the Akaike, Takeuchi, and Bayesian information criteria\nare adopted and the corresponding merits and drawbacks are discussed. At the\nanalysis stage, illustrating examples for the probability of correct model\nselection are presented showing the effectiveness of the proposed rules.\n",
"title": "Model Order Selection Rules For Covariance Structure Classification"
}
| null | null | null | null | true | null |
4995
| null |
Default
| null | null |
null |
{
"abstract": " The lack of interpretability often makes black-box models difficult to be\napplied to many practical domains. For this reason, the current work, from the\nblack-box model input port, proposes to incorporate data-based prior\ninformation into the black-box soft-margin SVM model to enhance its\ninterpretability. The concept and incorporation mechanism of data-based prior\ninformation are successively developed, based on which the interpretable or\npartly interpretable SVM optimization model is designed and then solved through\nhandily rewriting the optimization problem as a nonlinear quadratic programming\nproblem. An algorithm for mining data-based linear prior information from data\nset is also proposed, which generates a linear expression with respect to two\nappropriate inputs identified from all inputs of system. At last, the proposed\ninterpretability enhancement strategy is applied to eight benchmark examples\nfor effectiveness exhibition.\n",
"title": "Enhancing Interpretability of Black-box Soft-margin SVM by Integrating Data-based Priors"
}
| null | null | null | null | true | null |
4996
| null |
Default
| null | null |
null |
{
"abstract": " In many applications requiring multiple inputs to obtain a desired output, if\nany of the input data is missing, it often introduces large amounts of bias.\nAlthough many techniques have been developed for imputing missing data, the\nimage imputation is still difficult due to complicated nature of natural\nimages. To address this problem, here we proposed a novel framework for missing\nimage data imputation, called Collaborative Generative Adversarial Network\n(CollaGAN). CollaGAN converts an image imputation problem to a multi-domain\nimages-to-image translation task so that a single generator and discriminator\nnetwork can successfully estimate the missing data using the remaining clean\ndata set. We demonstrate that CollaGAN produces the images with a higher visual\nquality compared to the existing competing approaches in various image\nimputation tasks.\n",
"title": "CollaGAN : Collaborative GAN for Missing Image Data Imputation"
}
| null | null | null | null | true | null |
4997
| null |
Default
| null | null |
null |
{
"abstract": " In topos theory it is well-known that any nucleus j gives rise to a\ntranslation of intuitionistic logic into itself in a way which generalises the\nGoedel-Gentzen negative translation. Here we show that there exists a similar\nj-translation which is more in the spirit of Kuroda's negative translation. The\nkey is to apply the nucleus not only to the entire formula and universally\nquantified subformulas, but to conclusions of implications as well. The\ndevelopment is entirely syntactic and no knowledge of topos theory is required\nto read this small note.\n",
"title": "A Kuroda-style j-translation"
}
| null | null | null | null | true | null |
4998
| null |
Default
| null | null |
null |
{
"abstract": " Modulating the amplitude and phase of light is at the heart of many\napplications such as wavefront shaping, transformation optics, phased arrays,\nmodulators and sensors. Performing this task with high efficiency and small\nfootprint is a formidable challenge. Metasurfaces and plasmonics are promising\n, but metals exhibit weak electro-optic effects. Two-dimensional materials,\nsuch as graphene, have shown great performance as modulators with small drive\nvoltages. Here we show a graphene plasmonic phase modulator which is capable of\ntuning the phase between 0 and 2{\\pi} in situ. With a footprint of 350nm it is\nmore than 30 times smaller than the 10.6$\\mu$m free space wavelength. The\nmodulation is achieved by spatially controlling the plasmon phase velocity in a\ndevice where the spatial carrier density profile is tunable. We provide a\nscattering theory for plasmons propagating through spatial density profiles.\nThis work constitutes a first step towards two-dimensional transformation\noptics for ultra-compact modulators and biosensing.\n",
"title": "Electrical 2π phase control of infrared light in a 350nm footprint using graphene plasmons"
}
| null | null |
[
"Physics"
] | null | true | null |
4999
| null |
Validated
| null | null |
null |
{
"abstract": " We show that on any translation surface, if a regular point is contained in a\nsimple closed geodesic, then it is contained in infinitely many simple closed\ngeodesics, whose directions are dense in the unit circle. Moreover, the set of\npoints that are not contained in any simple closed geodesic is finite. We also\nconstruct explicit examples showing that such points exist. For a surface in\nany hyperelliptic component, we show that this finite exceptional set is\nactually empty. The proofs of our results use Apisa's classifications of\nperiodic points and of $\\GL(2,\\R)$ orbit closures in hyperelliptic components,\nas well as a recent result of Eskin-Filip-Wright.\n",
"title": "Existence of closed geodesics through a regular point on translation surfaces"
}
| null | null |
[
"Mathematics"
] | null | true | null |
5000
| null |
Validated
| null | null |
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