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dict | prediction
null | prediction_agent
null | annotation
list | annotation_agent
null | multi_label
bool 1
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{
"abstract": " A local existence and uniqueness theorem for ODEs in the special algebra of\ngeneralized functions is established, as well as versions including parameters\nand dependence on initial values in the generalized sense. Finally, a Frobenius\ntheorem is proved. In all these results, composition of generalized functions\nis based on the notion of c-boundedness.\n",
"title": "Ordinary differential equations in algebras of generalized functions"
}
| null | null |
[
"Mathematics"
] | null | true | null |
17601
| null |
Validated
| null | null |
null |
{
"abstract": " The Mapper produces a compact summary of high dimensional data as a\nsimplicial complex. We study the problem of quantifying the interestingness of\nsubpopulations in a Mapper, which appear as long paths, flares, or loops.\nFirst, we create a weighted directed graph G using the 1-skeleton of the\nMapper. We use the average values at the vertices of a target function to\ndirect edges (from low to high). The difference between the average values at\nvertices (high-low) is set as the edge's weight. Covariation of the remaining h\nfunctions (independent variables) is captured by a h-bit binary signature\nassigned to the edge. An interesting path in G is a directed path whose edges\nall have the same signature. We define the interestingness score of such a path\nas a sum of its edge weights multiplied by a nonlinear function of their ranks\nin the path.\nSecond, we study three optimization problems on this graph G. In the problem\nMax-IP, we seek an interesting path in G with the maximum interestingness\nscore. We show that Max-IP is NP-complete. For the special case when G is a\ndirected acyclic graph (DAG), we show that Max-IP can be solved in polynomial\ntime - in O(mnd_i) where d_i is the maximum indegree of a vertex in G.\nIn the more general problem IP, the goal is to find a collection of\nedge-disjoint interesting paths such that the overall sum of their\ninterestingness scores is maximized. We also study a variant of IP termed k-IP,\nwhere the goal is to identify a collection of edge-disjoint interesting paths\neach with k edges, and their total interestingness score is maximized. While\nk-IP can be solved in polynomial time for k <= 2, we show k-IP is NP-complete\nfor k >= 3 even when G is a DAG. We develop polynomial time heuristics for IP\nand k-IP on DAGs.\n",
"title": "Interesting Paths in the Mapper"
}
| null | null | null | null | true | null |
17602
| null |
Default
| null | null |
null |
{
"abstract": " This paper presents a three dimensional collision avoidance approach for\naerial vehicles inspired by coordinated behaviors in biological groups. The\nproposed strategy aims to enable a group of vehicles to converge to a common\ndestination point avoiding collisions with each other and with moving obstacles\nin their environment. The interaction rules lead the agents to adapt their\nvelocity vectors through a modification of the relative bearing angle and the\nrelative elevation. Moreover the model satisfies the limited field of view\nconstraints resulting from individual perception sensitivity. From the proposed\nindividual based model, a mean-field kinetic model is derived. Simulations are\nperformed to show the effectiveness of the proposed model.\n",
"title": "On a three dimensional vision based collision avoidance model"
}
| null | null | null | null | true | null |
17603
| null |
Default
| null | null |
null |
{
"abstract": " In this paper, we consider the problems for covering multiple intervals on a\nline. Given a set $B$ of $m$ line segments (called \"barriers\") on a horizontal\nline $L$ and another set $S$ of $n$ horizontal line segments of the same length\nin the plane, we want to move all segments of $S$ to $L$ so that their union\ncovers all barriers and the maximum movement of all segments of $S$ is\nminimized. Previously, an $O(n^3\\log n)$-time algorithm was given for the case\n$m=1$. In this paper, we propose an $O(n^2\\log n\\log \\log n+nm\\log m)$-time\nalgorithm for a more general setting with any $m\\geq 1$, which also improves\nthe previous work when $m=1$. We then consider a line-constrained version of\nthe problem in which the segments of $S$ are all initially on the line $L$.\nPreviously, an $O(n\\log n)$-time algorithm was known for the case $m=1$. We\npresent an algorithm of $O(m\\log m+n\\log m \\log n)$ time for any $m\\geq 1$.\nThese problems may have applications in mobile sensor barrier coverage in\nwireless sensor networks.\n",
"title": "Algorithms for Covering Multiple Barriers"
}
| null | null |
[
"Computer Science"
] | null | true | null |
17604
| null |
Validated
| null | null |
null |
{
"abstract": " We examine how the institutional context affects the relationship between\ngender and opportunity entrepreneurship. To do this, we develop a multi-level\nmodel that connects feminist theory at the micro-level to institutional theory\nat the macro-level. It is hypothesized that the gender gap in opportunity\nentrepreneurship is more pronounced in low-quality institutional contexts and\nless pronounced in high-quality institutional contexts. Using data from the\nGlobal Entrepreneurship Monitor (GEM) and regulation data from the economic\nfreedom of the world index (EFW), we test our predictions and find evidence in\nsupport of our model. Our findings suggest that, while there is a gender gap in\nentrepreneurship, these disparities are reduced as the quality of the\ninstitutional context improves.\n",
"title": "Shattering the glass ceiling? How the institutional context mitigates the gender gap in entrepreneurship"
}
| null | null | null | null | true | null |
17605
| null |
Default
| null | null |
null |
{
"abstract": " A great variety of text tasks such as topic or spam identification, user\nprofiling, and sentiment analysis can be posed as a supervised learning problem\nand tackle using a text classifier. A text classifier consists of several\nsubprocesses, some of them are general enough to be applied to any supervised\nlearning problem, whereas others are specifically designed to tackle a\nparticular task, using complex and computational expensive processes such as\nlemmatization, syntactic analysis, etc. Contrary to traditional approaches, we\npropose a minimalistic and wide system able to tackle text classification tasks\nindependent of domain and language, namely microTC. It is composed by some easy\nto implement text transformations, text representations, and a supervised\nlearning algorithm. These pieces produce a competitive classifier even in the\ndomain of informally written text. We provide a detailed description of microTC\nalong with an extensive experimental comparison with relevant state-of-the-art\nmethods. mircoTC was compared on 30 different datasets. Regarding accuracy,\nmicroTC obtained the best performance in 20 datasets while achieves competitive\nresults in the remaining 10. The compared datasets include several problems\nlike topic and polarity classification, spam detection, user profiling and\nauthorship attribution. Furthermore, it is important to state that our approach\nallows the usage of the technology even without knowledge of machine learning\nand natural language processing.\n",
"title": "An Automated Text Categorization Framework based on Hyperparameter Optimization"
}
| null | null | null | null | true | null |
17606
| null |
Default
| null | null |
null |
{
"abstract": " Endovascular sealing is a new technique for the repair of abdominal aortic\naneurysms. Commercially available in Europe since~2013, it takes a\nrevolutionary approach to aneurysm repair through minimally invasive\ntechniques. Although aneurysm sealing may be thought as more stable than\nconventional endovascular stent graft repairs, post-implantation movement of\nthe endoprosthesis has been described, potentially leading to late\ncomplications. The paper presents for the first time a model, which explains\nthe nature of forces, in static and dynamic regimes, acting on sealed abdominal\naortic aneurysms, with references to real case studies. It is shown that\nelastic deformation of the aorta and of the endoprosthesis induced by static\nforces and vibrations during daily activities can potentially promote undesired\nmovements of the endovascular sealing structure.\n",
"title": "Abdominal aortic aneurysms and endovascular sealing: deformation and dynamic response"
}
| null | null | null | null | true | null |
17607
| null |
Default
| null | null |
null |
{
"abstract": " MapReduce framework is the de facto standard in Hadoop. Considering the data\nlocality in data centers, the load balancing problem of map tasks is a special\ncase of affinity scheduling problem. There is a huge body of work on affinity\nscheduling, proposing heuristic algorithms which try to increase data locality\nin data centers like Delay Scheduling and Quincy. However, not enough attention\nhas been put on theoretical guarantees on throughput and delay optimality of\nsuch algorithms. In this work, we present and compare different algorithms and\ndiscuss their shortcoming and strengths. To the best of our knowledge, most\ndata centers are using static load balancing algorithms which are not efficient\nin any ways and results in wasting the resources and causing unnecessary delays\nfor users.\n",
"title": "Affinity Scheduling and the Applications on Data Center Scheduling with Data Locality"
}
| null | null | null | null | true | null |
17608
| null |
Default
| null | null |
null |
{
"abstract": " We consider the topic of multivariate regression on manifold-valued output,\nthat is, for a multivariate observation, its output response lies on a\nmanifold. Moreover, we propose a new regression model to deal with the presence\nof grossly corrupted manifold-valued responses, a bottleneck issue commonly\nencountered in practical scenarios. Our model first takes a correction step on\nthe grossly corrupted responses via geodesic curves on the manifold, and then\nperforms multivariate linear regression on the corrected data. This results in\na nonconvex and nonsmooth optimization problem on manifolds. To this end, we\npropose a dedicated approach named PALMR, by utilizing and extending the\nproximal alternating linearized minimization techniques. Theoretically, we\ninvestigate its convergence property, where it is shown to converge to a\ncritical point under mild conditions. Empirically, we test our model on both\nsynthetic and real diffusion tensor imaging data, and show that our model\noutperforms other multivariate regression models when manifold-valued responses\ncontain gross errors, and is effective in identifying gross errors.\n",
"title": "Multivariate Regression with Gross Errors on Manifold-valued Data"
}
| null | null | null | null | true | null |
17609
| null |
Default
| null | null |
null |
{
"abstract": " We study the problem of finding a small subset of items that is\n\\emph{agreeable} to all agents, meaning that all agents value the subset at\nleast as much as its complement. Previous work has shown worst-case bounds,\nover all instances with a given number of agents and items, on the number of\nitems that may need to be included in such a subset. Our goal in this paper is\nto efficiently compute an agreeable subset whose size approximates the size of\nthe smallest agreeable subset for a given instance. We consider three\nwell-known models for representing the preferences of the agents: ordinal\npreferences on single items, the value oracle model, and additive utilities. In\neach of these models, we establish virtually tight bounds on the approximation\nratio that can be obtained by algorithms running in polynomial time.\n",
"title": "Computing an Approximately Optimal Agreeable Set of Items"
}
| null | null | null | null | true | null |
17610
| null |
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| null | null |
null |
{
"abstract": " Sketch-based modeling strives to bring the ease and immediacy of drawing to\nthe 3D world. However, while drawings are easy for humans to create, they are\nvery challenging for computers to interpret due to their sparsity and\nambiguity. We propose a data-driven approach that tackles this challenge by\nlearning to reconstruct 3D shapes from one or more drawings. At the core of our\napproach is a deep convolutional neural network (CNN) that predicts occupancy\nof a voxel grid from a line drawing. This CNN provides us with an initial 3D\nreconstruction as soon as the user completes a single drawing of the desired\nshape. We complement this single-view network with an updater CNN that refines\nan existing prediction given a new drawing of the shape created from a novel\nviewpoint. A key advantage of our approach is that we can apply the updater\niteratively to fuse information from an arbitrary number of viewpoints, without\nrequiring explicit stroke correspondences between the drawings. We train both\nCNNs by rendering synthetic contour drawings from hand-modeled shape\ncollections as well as from procedurally-generated abstract shapes. Finally, we\nintegrate our CNNs in a minimal modeling interface that allows users to\nseamlessly draw an object, rotate it to see its 3D reconstruction, and refine\nit by re-drawing from another vantage point using the 3D reconstruction as\nguidance. The main strengths of our approach are its robustness to freehand\nbitmap drawings, its ability to adapt to different object categories, and the\ncontinuum it offers between single-view and multi-view sketch-based modeling.\n",
"title": "3D Sketching using Multi-View Deep Volumetric Prediction"
}
| null | null | null | null | true | null |
17611
| null |
Default
| null | null |
null |
{
"abstract": " We study the problem of ranking a set of items from nonactively chosen\npairwise preferences where each item has feature information with it. We\npropose and characterize a very broad class of preference matrices giving rise\nto the Feature Low Rank (FLR) model, which subsumes several models ranging from\nthe classic Bradley-Terry-Luce (BTL) (Bradley and Terry 1952) and Thurstone\n(Thurstone 1927) models to the recently proposed blade-chest (Chen and Joachims\n2016) and generic low-rank preference (Rajkumar and Agarwal 2016) models. We\nuse the technique of matrix completion in the presence of side information to\ndevelop the Inductive Pairwise Ranking (IPR) algorithm that provably learns a\ngood ranking under the FLR model, in a sample-efficient manner. In practice,\nthrough systematic synthetic simulations, we confirm our theoretical findings\nregarding improvements in the sample complexity due to the use of feature\ninformation. Moreover, on popular real-world preference learning datasets, with\nas less as 10% sampling of the pairwise comparisons, our method recovers a good\nranking.\n",
"title": "Inductive Pairwise Ranking: Going Beyond the n log(n) Barrier"
}
| null | null | null | null | true | null |
17612
| null |
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| null | null |
null |
{
"abstract": " SAGA is a fast incremental gradient method on the finite sum problem and its\neffectiveness has been tested on a vast of applications. In this paper, we\nanalyze SAGA on a class of non-strongly convex and non-convex statistical\nproblem such as Lasso, group Lasso, Logistic regression with $\\ell_1$\nregularization, linear regression with SCAD regularization and Correct Lasso.\nWe prove that SAGA enjoys the linear convergence rate up to the statistical\nestimation accuracy, under the assumption of restricted strong convexity (RSC).\nIt significantly extends the applicability of SAGA in convex and non-convex\noptimization.\n",
"title": "SAGA and Restricted Strong Convexity"
}
| null | null | null | null | true | null |
17613
| null |
Default
| null | null |
null |
{
"abstract": " The effects of nitridation on the density of traps at SiO$_2$/SiC interfaces\nnear the conduction band edge were qualitatively examined by a simple, newly\ndeveloped characterization method that utilizes Hall effect measurements and\nsplit capacitance-voltage measurements. The results showed a significant\nreduction in the density of interface traps near the conduction band edge by\nnitridation, as well as the high density of interface traps that was not\neliminated by nitridation.\n",
"title": "Characterization of Traps at Nitrided SiO$_2$/SiC Interfaces near the Conduction Band Edge by using Hall Effect Measurements"
}
| null | null | null | null | true | null |
17614
| null |
Default
| null | null |
null |
{
"abstract": " We derive the finite temperature Keldysh response theory for interacting\nfermions in the presence of quenched disorder, as applicable to any of the 10\nAltland-Zirnbauer classes in an Anderson delocalized phase with at least a U(1)\ncontinuous symmetry. In this formulation of the interacting Finkel'stein\nnonlinear sigma model, the statistics of one-body wave functions are encoded by\nthe constrained matrix field, while physical correlations follow from the\nhydrodynamic density or spin response field, which decouples the interactions.\nIntegrating out the matrix field first, we obtain weak (anti)localization and\nAltshuler-Aronov quantum conductance corrections from the hydrodynamic response\nfunction. This procedure automatically incorporates the correct infrared\nphysics, and in particular gives the Altshuler-Aronov-Khmelnitsky (AAK)\nequations for dephasing of weak (anti)localization due to electron-electron\ncollisions. We explicate the method by deriving known quantum corrections in\ntwo dimensions for the symplectic metal class AII, as well as the spin-SU(2)\ninvariant superconductor classes C and CI. We show that conductance corrections\ndue to the special modes at zero energy in nonstandard classes are\nautomatically cut off by temperature, as previously expected, while the\nWigner-Dyson class Cooperon modes that persist to all energies are cut by\ndephasing. We also show that for short-ranged interactions, the standard\nself-consistent solution for the dephasing rate is equivalent to a diagrammatic\nsummation via the self-consistent Born approximation. This should be compared\nto the AAK solution for long-ranged Coulomb interactions, which exploits the\nMarkovian noise correlations induced by thermal fluctuations of the\nelectromagnetic field. We discuss prospects for exploring the many-body\nlocalization transition from the ergodic side as a dephasing catastrophe in\nshort-range interacting models.\n",
"title": "Response theory of the ergodic many-body delocalized phase: Keldysh Finkel'stein sigma models and the 10-fold way"
}
| null | null | null | null | true | null |
17615
| null |
Default
| null | null |
null |
{
"abstract": " This work introduces a tensor-based method to perform supervised\nclassification on spatiotemporal data processed in an echo state network.\nTypically when performing supervised classification tasks on data processed in\nan echo state network, the entire collection of hidden layer node states from\nthe training dataset is shaped into a matrix, allowing one to use standard\nlinear algebra techniques to train the output layer. However, the collection of\nhidden layer states is multidimensional in nature, and representing it as a\nmatrix may lead to undesirable numerical conditions or loss of spatial and\ntemporal correlations in the data.\nThis work proposes a tensor-based supervised classification method on echo\nstate network data that preserves and exploits the multidimensional nature of\nthe hidden layer states. The method, which is based on orthogonal Tucker\ndecompositions of tensors, is compared with the standard linear output weight\napproach in several numerical experiments on both synthetic and natural data.\nThe results show that the tensor-based approach tends to outperform the\nstandard approach in terms of classification accuracy.\n",
"title": "Classification via Tensor Decompositions of Echo State Networks"
}
| null | null | null | null | true | null |
17616
| null |
Default
| null | null |
null |
{
"abstract": " Given a set of baseline assumptions, a breakdown frontier is the boundary\nbetween the set of assumptions which lead to a specific conclusion and those\nwhich do not. In a potential outcomes model with a binary treatment, we\nconsider two conclusions: First, that ATE is at least a specific value (e.g.,\nnonnegative) and second that the proportion of units who benefit from treatment\nis at least a specific value (e.g., at least 50\\%). For these conclusions, we\nderive the breakdown frontier for two kinds of assumptions: one which indexes\nrelaxations of the baseline random assignment of treatment assumption, and one\nwhich indexes relaxations of the baseline rank invariance assumption. These\nclasses of assumptions nest both the point identifying assumptions of random\nassignment and rank invariance and the opposite end of no constraints on\ntreatment selection or the dependence structure between potential outcomes.\nThis frontier provides a quantitative measure of robustness of conclusions to\nrelaxations of the baseline point identifying assumptions. We derive\n$\\sqrt{N}$-consistent sample analog estimators for these frontiers. We then\nprovide two asymptotically valid bootstrap procedures for constructing lower\nuniform confidence bands for the breakdown frontier. As a measure of\nrobustness, estimated breakdown frontiers and their corresponding confidence\nbands can be presented alongside traditional point estimates and confidence\nintervals obtained under point identifying assumptions. We illustrate this\napproach in an empirical application to the effect of child soldiering on\nwages. We find that sufficiently weak conclusions are robust to simultaneous\nfailures of rank invariance and random assignment, while some stronger\nconclusions are fairly robust to failures of rank invariance but not\nnecessarily to relaxations of random assignment.\n",
"title": "Inference on Breakdown Frontiers"
}
| null | null |
[
"Statistics"
] | null | true | null |
17617
| null |
Validated
| null | null |
null |
{
"abstract": " We study detection methods for multivariable signals under dependent noise.\nThe main focus is on three-dimensional signals, i.e. on signals in the\nspace-time domain. Examples for such signals are multifaceted. They include\ngeographic and climatic data as well as image data, that are observed over a\nfixed time horizon. We assume that the signal is observed as a finite block of\nnoisy samples whereby we are interested in detecting changes from a given\nreference signal. Our detector statistic is based on a sequential partial sum\nprocess, related to classical signal decomposition and reconstruction\napproaches applied to the sampled signal. We show that this detector process\nconverges weakly under the no change null hypothesis that the signal coincides\nwith the reference signal, provided that the spatial-temporal partial sum\nprocess associated to the random field of the noise terms disturbing the\nsampled signal con- verges to a Brownian motion. More generally, we also\nestablish the limiting distribution under a wide class of local alternatives\nthat allows for smooth as well as discontinuous changes. Our results also cover\nextensions to the case that the reference signal is unknown. We conclude with\nan extensive simulation study of the detection algorithm.\n",
"title": "Sequential Detection of Three-Dimensional Signals under Dependent Noise"
}
| null | null | null | null | true | null |
17618
| null |
Default
| null | null |
null |
{
"abstract": " Singular limits of 6D F-theory compactifications are often captured by\nT-branes, namely a non-abelian configuration of intersecting 7-branes with a\nnilpotent matrix of normal deformations. The long distance approximation of\nsuch 7-branes is a Hitchin-like system in which simple and irregular poles\nemerge at marked points of the geometry. When multiple matter fields localize\nat the same point in the geometry, the associated Higgs field can exhibit\nirregular behavior, namely poles of order greater than one. This provides a\ngeometric mechanism to engineer wild Higgs bundles. Physical constraints such\nas anomaly cancellation and consistent coupling to gravity also limit the order\nof such poles. Using this geometric formulation, we unify seemingly different\nwild Hitchin systems in a single framework in which orders of poles become\nadjustable parameters dictated by tuning gauge singlet moduli of the F-theory\nmodel.\n",
"title": "T-Branes at the Limits of Geometry"
}
| null | null | null | null | true | null |
17619
| null |
Default
| null | null |
null |
{
"abstract": " Crystal structures and the Bloch theorem play a fundamental role in condensed\nmatter physics. We extend the static crystal to the dynamic \"space-time\"\ncrystal characterized by the general intertwined space-time periodicities in\n$D+1$ dimensions, which include both the static crystal and the Floquet crystal\nas special cases. A new group structure dubbed \"space-time\" group is\nconstructed to describe the discrete symmetries of space-time crystal. Compared\nto space and magnetic groups, space-time group is augmented by \"time-screw\"\nrotations and \"time-glide\" reflections involving fractional translations along\nthe time direction. A complete classification of the 13 space-time groups in\n1+1D is performed. The Kramers-type degeneracy can arise from the glide\ntime-reversal symmetry without the half-integer spinor structure, which\nconstrains the winding number patterns of spectral dispersions. In 2+1D,\nnon-symmorphic space-time symmetries enforce spectral degeneracies, leading to\nprotected Floquet semi-metal states. Our work provides a general framework for\nfurther studying topological properties of the $D+1$ dimensional space-time\ncrystal.\n",
"title": "Space-time crystal and space-time group"
}
| null | null |
[
"Physics"
] | null | true | null |
17620
| null |
Validated
| null | null |
null |
{
"abstract": " We consider a multi-way massive multiple-input multiple-output relay network\nwith zero-forcing processing at the relay. By taking into account the\ntime-division duplex protocol with channel estimation, we derive an analytical\napproximation of the spectral efficiency. This approximation is very tight and\nsimple which enables us to analyze the system performance, as well as, to\ncompare the spectral efficiency with zero-forcing and maximum-ratio processing.\nOur results show that by using a very large number of relay antennas and with\nthe zero-forcing technique, we can simultaneously serve many active users in\nthe same time-frequency resource, each with high spectral efficiency.\n",
"title": "On the Performance of Zero-Forcing Processing in Multi-Way Massive MIMO Relay Networks"
}
| null | null | null | null | true | null |
17621
| null |
Default
| null | null |
null |
{
"abstract": " In this paper we introduce and study motives for rational homotopy types.\n",
"title": "Motivic rational homotopy type"
}
| null | null | null | null | true | null |
17622
| null |
Default
| null | null |
null |
{
"abstract": " This work extends the Elsner & Wandelt (2013) iterative method for efficient,\npreconditioner-free Wiener filtering to cases in which the noise covariance\nmatrix is dense, but can be decomposed into a sum whose parts are sparse in\nconvenient bases. The new method, which uses multiple messenger fields,\nreproduces Wiener filter solutions for test problems, and we apply it to a case\nbeyond the reach of the Elsner & Wandelt (2013) method. We compute the Wiener\nfilter solution for a simulated Cosmic Microwave Background map that contains\nspatially-varying, uncorrelated noise, isotropic $1/f$ noise, and large-scale\nhorizontal stripes (like those caused by the atmospheric noise). We discuss\nsimple extensions that can filter contaminated modes or inverse-noise filter\nthe data. These techniques help to address complications in the noise\nproperties of maps from current and future generations of ground-based\nMicrowave Background experiments, like Advanced ACTPol, Simons Observatory, and\nCMB-S4.\n",
"title": "Preconditioner-free Wiener filtering with a dense noise matrix"
}
| null | null | null | null | true | null |
17623
| null |
Default
| null | null |
null |
{
"abstract": " Self-consistent treatment of cosmological structure formation and expansion\nwithin the context of classical general relativity may lead to \"extra\"\nexpansion above that expected in a structureless universe. We argue that in\ncomparison to an early-epoch, extrapolated Einstein-de Sitter model, about\n10-15% \"extra\" expansion is sufficient at the present to render superfluous the\n\"dark energy\" 68% contribution to the energy density budget, and that this is\nobservationally realistic.\n",
"title": "Order-unity argument for structure-generated \"extra\" expansion"
}
| null | null | null | null | true | null |
17624
| null |
Default
| null | null |
null |
{
"abstract": " Let $K/F$ be a finite extension of number fields of degree $n \\geq 2$. We\nestablish effective field-uniform unconditional upper bounds for the least norm\nof a prime ideal of $F$ which is degree 1 over $\\mathbb{Q}$ and does not ramify\nor split completely in $K$. We improve upon the previous best known general\nestimates due to X. Li when $F = \\mathbb{Q}$ and Murty-Patankar when $K/F$ is\nGalois. Our bounds are the first when $K/F$ is not assumed to be Galois and $F\n\\neq \\mathbb{Q}$.\n",
"title": "The least unramified prime which does not split completely"
}
| null | null | null | null | true | null |
17625
| null |
Default
| null | null |
null |
{
"abstract": " We consider the class of Rudin-Shapiro-like polynomials, whose $L^4$ norms on\nthe complex unit circle were studied by Borwein and Mossinghoff. The polynomial\n$f(z)=f_0+f_1 z + \\cdots + f_d z^d$ is identified with the sequence\n$(f_0,f_1,\\ldots,f_d)$ of its coefficients. From the $L^4$ norm of a\npolynomial, one can easily calculate the autocorrelation merit factor of its\nassociated sequence, and conversely. In this paper, we study the\ncrosscorrelation properties of pairs of sequences associated to\nRudin-Shapiro-like polynomials. We find an explicit formula for the\ncrosscorrelation merit factor. A computer search is then used to find pairs of\nRudin-Shapiro-like polynomials whose autocorrelation and crosscorrelation merit\nfactors are simultaneously high. Pursley and Sarwate proved a bound that limits\nhow good this combined autocorrelation and crosscorrelation performance can be.\nWe find infinite families of polynomials whose performance approaches quite\nclose to this fundamental limit.\n",
"title": "Crosscorrelation of Rudin-Shapiro-Like Polynomials"
}
| null | null |
[
"Computer Science",
"Mathematics"
] | null | true | null |
17626
| null |
Validated
| null | null |
null |
{
"abstract": " We highlight how Rule-based Integration (Rubi) is an enhanced method of\nsymbolic integration which allows for the integration of many difficult\nintegrals not accomplished by other computer algebra systems. Using Rubi, many\nintegration techniques become tractable. Integrals are approached using\nstep-wise simplification, hence distilling an integral (if the solution is\nunknown) into composite integrals which highlight yet undiscovered integration\nrules. The motivating example we use is the derivation of the updated series\nexpansion of the quark mass renormalization group equation (RGE) to five-loop\norder. This series provides the relation between a light quark mass in the\nmodified minimal subtraction ($\\overline{\\text{MS}}$) scheme defined at some\ngiven scale, e.g. at the tau-lepton mass scale, and another chosen energy\nscale, $s$. This relation explicitly depicts the renormalization scheme\ndependence of the running quark mass on the scale parameter, $s$, and is\nimportant in accurately determining a light quark mass at a chosen scale. The\nfive-loop QCD $\\beta(a_s)$ and $\\gamma(a_s)$ functions are used in this\ndetermination.\n",
"title": "An Application of Rubi: Series Expansion of the Quark Mass Renormalization Group Equation"
}
| null | null | null | null | true | null |
17627
| null |
Default
| null | null |
null |
{
"abstract": " In this paper, we analyze the performance of a time-slotted multi-antenna\nwireless powered communication (WPC) system, where a wireless device first\nharvests radio frequency (RF) energy from a power station (PS) in the downlink\nto facilitate information transfer to an information receiving station (IRS) in\nthe uplink. The main goal of this paper is to provide insights and guidelines\nfor the design of practical WPC systems. To this end, we adopt a recently\nproposed parametric non-linear RF energy harvesting (EH) model, which has been\nshown to accurately model the end-to-end non-linearity of practical RF EH\ncircuits. In order to enhance the RF power transfer efficiency, maximum ratio\ntransmission is adopted at the PS to focus the energy signals on the wireless\ndevice. Furthermore, at the IRS, maximum ratio combining is used. We analyze\nthe outage probability and the average throughput of information transfer,\nassuming Nakagami-$m$ fading uplink and downlink channels. Moreover, we study\nthe system performance as a function of the number of PS transmit antennas, the\nnumber of IRS receive antennas, the transmit power of the PS, the fading\nseverity, the transmission rate of the wireless device, and the EH time\nduration. In addition, we obtain a fixed point equation for the optimal\ntransmission rate and the optimal EH time duration that maximize the asymptotic\nthroughput for high PS transmit powers. All analytical results are corroborated\nby simulations.\n",
"title": "On the Performance of Wireless Powered Communication With Non-linear Energy Harvesting"
}
| null | null |
[
"Computer Science"
] | null | true | null |
17628
| null |
Validated
| null | null |
null |
{
"abstract": " We show that polarization states of electromagnetic waves can be manipulated\neasily using a single thin uniaxial crystal plate. By performing a rotational\ntransformation of the coordinates and controlling the thickness of the plate,\nwe can achieve a complete polarization conversion between TE wave and TM wave\nin a spectral band. We show that the off-diagonal element of the permittivity\nis the key for polarization conversion. Our analysis can explain clearly the\nresults found in experiments with metamaterials. Finally, we propose a simple\ndevice to realize unidirectional transmission based on polarization conversion\nand excitation of surface plasmon polaritons.\n",
"title": "Realizing polarization conversion and unidirectional transmission by using a uniaxial crystal plate"
}
| null | null | null | null | true | null |
17629
| null |
Default
| null | null |
null |
{
"abstract": " In empirical work in economics it is common to report standard errors that\naccount for clustering of units. Typically, the motivation given for the\nclustering adjustments is that unobserved components in outcomes for units\nwithin clusters are correlated. However, because correlation may occur across\nmore than one dimension, this motivation makes it difficult to justify why\nresearchers use clustering in some dimensions, such as geographic, but not\nothers, such as age cohorts or gender. It also makes it difficult to explain\nwhy one should not cluster with data from a randomized experiment. In this\npaper, we argue that clustering is in essence a design problem, either a\nsampling design or an experimental design issue. It is a sampling design issue\nif sampling follows a two stage process where in the first stage, a subset of\nclusters were sampled randomly from a population of clusters, while in the\nsecond stage, units were sampled randomly from the sampled clusters. In this\ncase the clustering adjustment is justified by the fact that there are clusters\nin the population that we do not see in the sample. Clustering is an\nexperimental design issue if the assignment is correlated within the clusters.\nWe take the view that this second perspective best fits the typical setting in\neconomics where clustering adjustments are used. This perspective allows us to\nshed new light on three questions: (i) when should one adjust the standard\nerrors for clustering, (ii) when is the conventional adjustment for clustering\nappropriate, and (iii) when does the conventional adjustment of the standard\nerrors matter.\n",
"title": "When Should You Adjust Standard Errors for Clustering?"
}
| null | null | null | null | true | null |
17630
| null |
Default
| null | null |
null |
{
"abstract": " We prove two results concerning an Ulam-type stability problem for\nhomomorphisms between lattices. One of them involves estimates by quite general\nerror functions; the other deals with approximate (join) homomorphisms in terms\nof certain systems of lattice neighborhoods. As a corollary, we obtain a\nstability result for approximately monotone functions.\n",
"title": "Approximate homomorphisms on lattices"
}
| null | null | null | null | true | null |
17631
| null |
Default
| null | null |
null |
{
"abstract": " In this communication, we describe a novel technique for event mining using a\ndecomposition based approach that combines non-parametric change-point\ndetection with LDA. We prove theoretical guarantees about sample-complexity and\nconsistency of the approach. In a companion paper, we will perform a thorough\nevaluation of our approach with detailed experiments.\n",
"title": "Learning Latent Events from Network Message Logs: A Decomposition Based Approach"
}
| null | null | null | null | true | null |
17632
| null |
Default
| null | null |
null |
{
"abstract": " Despite significant advances in artificial intelligence (AI) for computer\nvision, its application in medical imaging has been limited by the burden and\nlimits of expert-generated labels. We used images from optical coherence\ntomography angiography (OCTA), a relatively new imaging modality that measures\nperfusion of the retinal vasculature, to train an AI algorithm to generate\nvasculature maps from standard structural optical coherence tomography (OCT)\nimages of the same retinae, both exceeding the ability and bypassing the need\nfor expert labeling. Deep learning was able to infer perfusion of\nmicrovasculature from structural OCT images with similar fidelity to OCTA and\nsignificantly better than expert clinicians (P < 0.00001). OCTA suffers from\nneed of specialized hardware, laborious acquisition protocols, and motion\nartifacts; whereas our model works directly from standard OCT which are\nubiquitous and quick to obtain, and allows unlocking of large volumes of\npreviously collected standard OCT data both in existing clinical trials and\nclinical practice. This finding demonstrates a novel application of AI to\nmedical imaging, whereby subtle regularities between different modalities are\nused to image the same body part and AI is used to generate detailed and\naccurate inferences of tissue function from structure imaging.\n",
"title": "Generating retinal flow maps from structural optical coherence tomography with artificial intelligence"
}
| null | null | null | null | true | null |
17633
| null |
Default
| null | null |
null |
{
"abstract": " This paper generalises Mori's famous theorem about \"Projective manifolds with\nample tangent bundles\" to normal projective varieties in the following way:\nA normal projective variety over $\\mathbb{C}$ with ample tangent sheaf is\nisomorphic to the complex projective space.\n",
"title": "Varieties with Ample Tangent Sheaves"
}
| null | null | null | null | true | null |
17634
| null |
Default
| null | null |
null |
{
"abstract": " We investigate the dynamics of water confined in soft ionic nano-assemblies,\nan issue critical for a general understanding of the multi-scale\nstructure-function interplay in advanced materials. We focus in particular on\nhydrated perfluoro-sulfonic acid compounds employed as electrolytes in fuel\ncells. These materials form phase-separated morphologies that show outstanding\nproton-conducting properties, directly related to the state and dynamics of the\nabsorbed water. We have quantified water motion and ion transport by combining\nQuasi Elastic Neutron Scattering, Pulsed Field Gradient Nuclear Magnetic\nResonance, and Molecular Dynamics computer simulation. Effective water and ion\ndiffusion coefficients have been determined together with their variation upon\nhydration at the relevant atomic, nanoscopic and macroscopic scales, providing\na complete picture of transport. We demonstrate that confinement at the\nnanoscale and direct interaction with the charged interfaces produce anomalous\nsub-diffusion, due to a heterogeneous space-dependent dynamics within the ionic\nnanochannels. This is irrespective of the details of the chemistry of the\nhydrophobic confining matrix, confirming the statistical significance of our\nconclusions. Our findings turn out to indicate interesting connections and\npossibilities of cross-fertilization with other domains, including biophysics.\nThey also establish fruitful correspondences with advanced topics in\nstatistical mechanics, resulting in new possibilities for the analysis of\nNeutron scattering data.\n",
"title": "Water sub-diffusion in membranes for fuel cells"
}
| null | null | null | null | true | null |
17635
| null |
Default
| null | null |
null |
{
"abstract": " The main objective of this paper is to study the global strong solution of\nthe parabolic-hyperbolic incompressible magnetohydrodynamic (MHD) model in two\ndimensional space. Based on Agmon, Douglis and Nirenberg's estimates for the\nstationary Stokes equation and the Solonnikov's theorem of\n$L^p$-$L^q$-estimates for the evolution Stokes equation, it is shown that the\nmixed-type MHD equations exist a global strong solution.\n",
"title": "Global Strong Solution of a 2D coupled Parabolic-Hyperbolic Magnetohydrodynamic System"
}
| null | null | null | null | true | null |
17636
| null |
Default
| null | null |
null |
{
"abstract": " Planetary cores consist of liquid metals (low Prandtl number $Pr$) that\nconvect as the core cools. Here we study nonlinear convection in a rotating\n(low Ekman number $Ek$) planetary core using a fully 3D direct numerical\nsimulation. Near the critical thermal forcing (Rayleigh number $Ra$),\nconvection onsets as thermal Rossby waves, but as the $Ra$ increases, this\nstate is superceded by one dominated by advection. At moderate rotation, these\nstates (here called the weak branch and strong branch, respectively) are\nsmoothly connected. As the planetary core rotates faster, the smooth transition\nis replaced by hysteresis cycles and subcriticality until the weak branch\ndisappears entirely and the strong branch onsets in a turbulent state at $Ek <\n10^{-6}$. Here the strong branch persists even as the thermal forcing drops\nwell below the linear onset of convection ($Ra=0.7Ra_{crit}$ in this study). We\nhighlight the importance of the Reynolds stress, which is required for\nconvection to subsist below the linear onset. In addition, the Péclet number\nis consistently above 10 in the strong branch. We further note the presence of\na strong zonal flow that is nonetheless unimportant to the convective state.\nOur study suggests that, in the asymptotic regime of rapid rotation relevant\nfor planetary interiors, thermal convection of liquid metals in a sphere onsets\nthrough a subcritical bifurcation.\n",
"title": "Subcritical thermal convection of liquid metals in a rapidly rotating sphere"
}
| null | null | null | null | true | null |
17637
| null |
Default
| null | null |
null |
{
"abstract": " Followership is generally defined as a strategy that evolved to solve social\ncoordination problems, and particularly those involved in group movement.\nFollowership behaviour is particularly interesting in the context of\nroad-crossing behaviour because it involves other principles such as\nrisk-taking and evaluating the value of social information. This study sought\nto identify the cognitive mechanisms underlying decision-making by pedestrians\nwho follow another person across the road at the green or at the red light in\ntwo different countries (France and Japan). We used agent-based modelling to\nsimulate the road-crossing behaviours of pedestrians. This study showed that\nmodelling is a reliable means to test different hypotheses and find the exact\nprocesses underlying decision-making when crossing the road. We found that two\nprocesses suffice to simulate pedestrian behaviours. Importantly, the study\nrevealed differences between the two nationalities and between sexes in the\ndecision to follow and cross at the green and at the red light. Japanese\npedestrians are particularly attentive to the number of already departed\npedestrians and the number of waiting pedestrians at the red light, whilst\ntheir French counterparts only consider the number of pedestrians that have\nalready stepped off the kerb, thus showing the strong conformism of Japanese\npeople. Finally, the simulations are revealed to be similar to observations,\nnot only for the departure latencies but also for the number of crossing\npedestrians and the rates of illegal crossings. The conclusion suggests new\nsolutions for safety in transportation research.\n",
"title": "Decision-making processes underlying pedestrian behaviours at signalised crossings: Part 2. Do pedestrians show cultural herding behaviour ?"
}
| null | null |
[
"Quantitative Biology"
] | null | true | null |
17638
| null |
Validated
| null | null |
null |
{
"abstract": " We present improved Mars Odyssey Neutron Spectrometer (MONS) maps of\nnear-surface Water-Equivalent Hydrogen (WEH) on Mars that have intriguing\nimplications for the global distribution of \"excess\" ice, which occurs when the\nmass fraction of water ice exceeds the threshold amount needed to saturate the\npore volume in normal soils. We have refined the crossover technique of Feldman\net al. (2011) by using spatial deconvolution and Gaussian weighting to create\nthe first globally self-consistent map of WEH. At low latitudes, our new maps\nindicate that WEH exceeds 15% in several near-equatorial regions, such as\nArabia Terra, which has important implications for the types of hydrated\nminerals present at low latitudes. At high latitudes, we demonstrate that the\ndisparate MONS and Phoenix Robotic Arm (RA) observations of near surface WEH\ncan be reconciled by a three-layer model incorporating dry soil over fully\nsaturated pore ice over pure excess ice: such a three-layer model can also\npotentially explain the strong anticorrelation of subsurface ice content and\nice table depth observed at high latitudes. At moderate latitudes, we show that\nthe distribution of recently formed impact craters is also consistent with our\nlatest MONS results, as both the shallowest ice-exposing crater and deepest\nnon-ice-exposing crater at each impact site are in good agreement with our\npredictions of near-surface WEH. Overall, we find that our new mapping is\nconsistent with the widespread presence at mid-to-high Martian latitudes of\nrecently deposited shallow excess ice reservoirs that are not yet in\nequilibrium with the atmosphere.\n",
"title": "Driven by Excess? Climatic Implications of New Global Mapping of Near-Surface Water-Equivalent Hydrogen on Mars"
}
| null | null | null | null | true | null |
17639
| null |
Default
| null | null |
null |
{
"abstract": " Let $\\varphi:\\mathbb{R}\\rightarrow \\mathbb{R}$ be a continuously\ndifferentiable function on an interval $J\\subset\\mathbb{R}$ and let\n$\\boldsymbol{\\alpha}=(\\alpha_1,\\alpha_2)$ be a point with algebraic conjugate\ninteger coordinates of degree $\\leq n$ and of height $\\leq Q$. Denote by\n$\\tilde{M}^n_\\varphi(Q,\\gamma, J)$ the set of points $\\boldsymbol{\\alpha}$ such\nthat $|\\varphi(\\alpha_1)-\\alpha_2|\\leq c_1 Q^{-\\gamma}$. In this paper we show\nthat for a real $0<\\gamma<1$ and any sufficiently large $Q$ there exist\npositive values $c_2<c_3$, which are independent of $Q$, such that $c_2\\cdot\nQ^{n-\\gamma}<# \\tilde{M}^n_\\varphi(Q,\\gamma, J)< c_3\\cdot Q^{n-\\gamma}$.\n",
"title": "On distribution of points with conjugate algebraic integer coordinates close to planar curves"
}
| null | null | null | null | true | null |
17640
| null |
Default
| null | null |
null |
{
"abstract": " The navigation problem is classically approached in two steps: an exploration\nstep, where map-information about the environment is gathered; and an\nexploitation step, where this information is used to navigate efficiently. Deep\nreinforcement learning (DRL) algorithms, alternatively, approach the problem of\nnavigation in an end-to-end fashion. Inspired by the classical approach, we ask\nwhether DRL algorithms are able to inherently explore, gather and exploit\nmap-information over the course of navigation. We build upon Mirowski et al.\n[2017] work and introduce a systematic suite of experiments that vary three\nparameters: the agent's starting location, the agent's target location, and the\nmaze structure. We choose evaluation metrics that explicitly measure the\nalgorithm's ability to gather and exploit map-information. Our experiments show\nthat when trained and tested on the same maps, the algorithm successfully\ngathers and exploits map-information. However, when trained and tested on\ndifferent sets of maps, the algorithm fails to transfer the ability to gather\nand exploit map-information to unseen maps. Furthermore, we find that when the\ngoal location is randomized and the map is kept static, the algorithm is able\nto gather and exploit map-information but the exploitation is far from optimal.\nWe open-source our experimental suite in the hopes that it serves as a\nframework for the comparison of future algorithms and leads to the discovery of\nrobust alternatives to classical navigation methods.\n",
"title": "A Critical Investigation of Deep Reinforcement Learning for Navigation"
}
| null | null | null | null | true | null |
17641
| null |
Default
| null | null |
null |
{
"abstract": " This paper presents a thorough evaluation of several widely-used 3D\ncorrespondence grouping algorithms, motived by their significance in vision\ntasks relying on correct feature correspondences. A good correspondence\ngrouping algorithm is desired to retrieve as many as inliers from initial\nfeature matches, giving a rise in both precision and recall. Towards this rule,\nwe deploy the experiments on three benchmarks respectively addressing shape\nretrieval, 3D object recognition and point cloud registration scenarios. The\nvariety in application context brings a rich category of nuisances including\nnoise, varying point densities, clutter, occlusion and partial overlaps. It\nalso results to different ratios of inliers and correspondence distributions\nfor comprehensive evaluation. Based on the quantitative outcomes, we give a\nsummarization of the merits/demerits of the evaluated algorithms from both\nperformance and efficiency perspectives.\n",
"title": "Performance Evaluation of 3D Correspondence Grouping Algorithms"
}
| null | null | null | null | true | null |
17642
| null |
Default
| null | null |
null |
{
"abstract": " We present DeepPicar, a low-cost deep neural network based autonomous car\nplatform. DeepPicar is a small scale replication of a real self-driving car\ncalled DAVE-2 by NVIDIA. DAVE-2 uses a deep convolutional neural network (CNN),\nwhich takes images from a front-facing camera as input and produces car\nsteering angles as output. DeepPicar uses the same network architecture---9\nlayers, 27 million connections and 250K parameters---and can drive itself in\nreal-time using a web camera and a Raspberry Pi 3 quad-core platform. Using\nDeepPicar, we analyze the Pi 3's computing capabilities to support end-to-end\ndeep learning based real-time control of autonomous vehicles. We also\nsystematically compare other contemporary embedded computing platforms using\nthe DeepPicar's CNN-based real-time control workload. We find that all tested\nplatforms, including the Pi 3, are capable of supporting the CNN-based\nreal-time control, from 20 Hz up to 100 Hz, depending on hardware platform.\nHowever, we find that shared resource contention remains an important issue\nthat must be considered in applying CNN models on shared memory based embedded\ncomputing platforms; we observe up to 11.6X execution time increase in the CNN\nbased control loop due to shared resource contention. To protect the CNN\nworkload, we also evaluate state-of-the-art cache partitioning and memory\nbandwidth throttling techniques on the Pi 3. We find that cache partitioning is\nineffective, while memory bandwidth throttling is an effective solution.\n",
"title": "DeepPicar: A Low-cost Deep Neural Network-based Autonomous Car"
}
| null | null | null | null | true | null |
17643
| null |
Default
| null | null |
null |
{
"abstract": " Considering structure functions of the streamwise velocity component in a\nframework akin to the extended self-similarity hypothesis (ESS), de Silva\n\\textit{et al.} (\\textit{J. Fluid Mech.}, vol. 823,2017, pp. 498-510) observed\nthat remarkably the \\textit{large-scale} (energy-containing range) statistics\nin canonical wall bounded flows exhibit universal behaviour. In the present\nstudy, we extend this universality, which was seen to encompass also flows at\nmoderate Reynolds number, to Taylor-Couette flow. In doing so, we find that\nalso the transversal structure function of the spanwise velocity component\nexhibits the same universal behaviour across all flow types considered. We\nfurther demonstrate that these observations are consistent with predictions\ndeveloped based on an attached-eddy hypothesis. These considerations also yield\na possible explanation for the efficacy of the ESS framework by showing that it\nrelaxes the self-similarity assumption for the attached eddy contributions. By\ntaking the effect of streamwise alignment into account, the attached eddy model\npredicts different behaviour for structure functions in the streamwise and in\nthe spanwise directions and that this effect cancels in the ESS-framework ---\nboth consistent with the data. Moreover, it is demonstrated here that also the\nadditive constants, which were previously believed to be flow dependent, are\nindeed universal at least in turbulent boundary layers and pipe flow where\nhigh-Reynolds number data are currently available.\n",
"title": "Statistics of turbulence in the energy-containing range of Taylor-Couette compared to canonical wall-bounded flows"
}
| null | null |
[
"Physics"
] | null | true | null |
17644
| null |
Validated
| null | null |
null |
{
"abstract": " Compact modeling of inter-device radiation-induced leakage underneath the\ngateless thick STI oxide is presented and validated taking into account CMOS\ntechnology and hardness parameters, dose-rate and annealing effects, and\ndependence on electric modes under irradiation. It was shown that proposed\napproach can be applied for description of dose dependent static leakage\ncurrents in complex FPGA circuits.\n",
"title": "Physics-Based Modeling of TID Induced Global Static Leakage in Different CMOS Circuits"
}
| null | null | null | null | true | null |
17645
| null |
Default
| null | null |
null |
{
"abstract": " In this note it is shown that the class of all multipliers from the\n$d$-parameter Hardy space $H^1_{\\mathrm{prod}} (\\mathbb{T}^d)$ to $L^2\n(\\mathbb{T}^d)$ is properly contained in the class of all multipliers from $L\n\\log^{d/2} L (\\mathbb{T}^d)$ to $L^2(\\mathbb{T}^d)$.\n",
"title": "A multiplier inclusion theorem on product domains"
}
| null | null | null | null | true | null |
17646
| null |
Default
| null | null |
null |
{
"abstract": " We consider using a battery storage system simultaneously for peak shaving\nand frequency regulation through a joint optimization framework which captures\nbattery degradation, operational constraints and uncertainties in customer load\nand regulation signals. Under this framework, using real data we show the\nelectricity bill of users can be reduced by up to 15\\%. Furthermore, we\ndemonstrate that the saving from joint optimization is often larger than the\nsum of the optimal savings when the battery is used for the two individual\napplications. A simple threshold real-time algorithm is proposed and achieves\nthis super-linear gain. Compared to prior works that focused on using battery\nstorage systems for single applications, our results suggest that batteries can\nachieve much larger economic benefits than previously thought if they jointly\nprovide multiple services.\n",
"title": "Using Battery Storage for Peak Shaving and Frequency Regulation: Joint Optimization for Superlinear Gains"
}
| null | null | null | null | true | null |
17647
| null |
Default
| null | null |
null |
{
"abstract": " The nervous system encodes continuous information from the environment in the\nform of discrete spikes, and then decodes these to produce smooth motor\nactions. Understanding how spikes integrate, represent, and process information\nto produce behavior is one of the greatest challenges in neuroscience.\nInformation theory has the potential to help us address this challenge.\nInformational analyses of deep and feed-forward artificial neural networks\nsolving static input-output tasks, have led to the proposal of the\n\\emph{Information Bottleneck} principle, which states that deeper layers encode\nmore relevant yet minimal information about the inputs. Such an analyses on\nnetworks that are recurrent, spiking, and perform control tasks is relatively\nunexplored. Here, we present results from a Mutual Information analysis of a\nrecurrent spiking neural network that was evolved to perform the classic\npole-balancing task. Our results show that these networks deviate from the\n\\emph{Information Bottleneck} principle prescribed for feed-forward networks.\n",
"title": "Information Bottleneck in Control Tasks with Recurrent Spiking Neural Networks"
}
| null | null | null | null | true | null |
17648
| null |
Default
| null | null |
null |
{
"abstract": " We present an investigation of clumpy galaxies in the Hubble Ultra Deep Field\nat 0.5 $\\leq z \\leq$ 1.5 in the rest-frame far-ultraviolet (FUV) using HST WFC3\nbroadband imaging in F225W, F275W, and F336W. An analysis of 1,404 galaxies\nyields 209 galaxies that host 403 kpc-scale clumps. These host galaxies appear\nto be typical star-forming galaxies, with an average of 2 clumps per galaxy and\nreaching a maximum of 8 clumps. We measure the photometry of the clumps, and\ndetermine the mass, age, and star formation rates (SFR) utilizing the\nSED-fitting code FAST. We find that clumps make an average contribution of 19%\nto the total rest-frame FUV flux of their host galaxy. Individually, clumps\ncontribute a median of 5% to the host galaxy SFR and an average of $\\sim$4% to\nthe host galaxy mass, with total clump contributions to the host galaxy stellar\nmass ranging widely from less than 1% up to 93%. Clumps in the outskirts of\ngalaxies are typically younger, with higher star formation rates, than clumps\nin the inner regions. The results are consistent with clump migration theories\nin which clumps form through violent gravitational instabilities in gas-rich\nturbulent disks, eventually migrate toward the center of the galaxies, and\ncoalesce into the bulge.\n",
"title": "Physical Properties of Sub-galactic Clumps at 0.5 $\\leq z \\leq$ 1.5 in the UVUDF"
}
| null | null | null | null | true | null |
17649
| null |
Default
| null | null |
null |
{
"abstract": " We propose the use of incomplete dot products (IDP) to dynamically adjust the\nnumber of input channels used in each layer of a convolutional neural network\nduring feedforward inference. IDP adds monotonically non-increasing\ncoefficients, referred to as a \"profile\", to the channels during training. The\nprofile orders the contribution of each channel in non-increasing order. At\ninference time, the number of channels used can be dynamically adjusted to\ntrade off accuracy for lowered power consumption and reduced latency by\nselecting only a beginning subset of channels. This approach allows for a\nsingle network to dynamically scale over a computation range, as opposed to\ntraining and deploying multiple networks to support different levels of\ncomputation scaling. Additionally, we extend the notion to multiple profiles,\neach optimized for some specific range of computation scaling. We present\nexperiments on the computation and accuracy trade-offs of IDP for popular image\nclassification models and datasets. We demonstrate that, for MNIST and\nCIFAR-10, IDP reduces computation significantly, e.g., by 75%, without\nsignificantly compromising accuracy. We argue that IDP provides a convenient\nand effective means for devices to lower computation costs dynamically to\nreflect the current computation budget of the system. For example, VGG-16 with\n50% IDP (using only the first 50% of channels) achieves 70% in accuracy on the\nCIFAR-10 dataset compared to the standard network which achieves only 35%\naccuracy when using the reduced channel set.\n",
"title": "Incomplete Dot Products for Dynamic Computation Scaling in Neural Network Inference"
}
| null | null | null | null | true | null |
17650
| null |
Default
| null | null |
null |
{
"abstract": " Let $A$ be a commutative Noetherian ring containing a field $K$ of\ncharacteristic zero and let $R= A[X_1, \\ldots, X_m]$. Consider $R$ as standard\ngraded with $°A=0$ and $°X_i=1$ for all $i$. We present a few results\nabout the behavior of the graded components of local cohomology modules\n$H_I^i(R)$ where $I$ is an arbitrary homogeneous ideal in $R$. We mostly\nrestrict our attention to the Vanishing, Tameness and Rigidity problems.\n",
"title": "Graded components of Local cohomology modules II"
}
| null | null | null | null | true | null |
17651
| null |
Default
| null | null |
null |
{
"abstract": " This is the last part of a series of three papers entitled \"Four-dimensional\nPainlevé-type equations associated with ramified linear equations\". In this\nseries of papers we aim to construct the complete degeneration scheme of\nfour-dimensional Painlevé-type equations. In the present paper, we consider\nthe degeneration of the Garnier system in two variables and the Fuji-Suzuki\nsystem.\n",
"title": "Four-Dimensional Painlevé-Type Equations Associated with Ramified Linear Equations III: Garnier Systems and Fuji-Suzuki Systems"
}
| null | null | null | null | true | null |
17652
| null |
Default
| null | null |
null |
{
"abstract": " In the cost per click (CPC) pricing model, an advertiser pays an ad network\nonly when a user clicks on an ad; in turn, the ad network gives a share of that\nrevenue to the publisher where the ad was impressed. Still, advertisers may be\nunsatisfied with ad networks charging them for \"valueless\" clicks, or so-called\naccidental clicks. [...] Charging advertisers for such clicks is detrimental in\nthe long term as the advertiser may decide to run their campaigns on other ad\nnetworks. In addition, machine-learned click models trained to predict which ad\nwill bring the highest revenue may overestimate an ad click-through rate, and\nas a consequence negatively impacting revenue for both the ad network and the\npublisher. In this work, we propose a data-driven method to detect accidental\nclicks from the perspective of the ad network. We collect observations of time\nspent by users on a large set of ad landing pages - i.e., dwell time. We notice\nthat the majority of per-ad distributions of dwell time fit to a mixture of\ndistributions, where each component may correspond to a particular type of\nclicks, the first one being accidental. We then estimate dwell time thresholds\nof accidental clicks from that component. Using our method to identify\naccidental clicks, we then propose a technique that smoothly discounts the\nadvertiser's cost of accidental clicks at billing time. Experiments conducted\non a large dataset of ads served on Yahoo mobile apps confirm that our\nthresholds are stable over time, and revenue loss in the short term is\nmarginal. We also compare the performance of an existing machine-learned click\nmodel trained on all ad clicks with that of the same model trained only on\nnon-accidental clicks. There, we observe an increase in both ad click-through\nrate (+3.9%) and revenue (+0.2%) on ads served by the Yahoo Gemini network when\nusing the latter. [...]\n",
"title": "You Must Have Clicked on this Ad by Mistake! Data-Driven Identification of Accidental Clicks on Mobile Ads with Applications to Advertiser Cost Discounting and Click-Through Rate Prediction"
}
| null | null | null | null | true | null |
17653
| null |
Default
| null | null |
null |
{
"abstract": " An important task for many if not all the scientific domains is efficient\nknowledge integration, testing and codification. It is often solved with model\nconstruction in a controllable computational environment. In spite of that, the\nthroughput of in-silico simulation-based observations become similarly\nintractable for thorough analysis. This is especially the case in molecular\nbiology, which served as a subject for this study. In this project, we aimed to\ntest some approaches developed to deal with the curse of dimensionality. Among\nthese we found dimension reduction techniques especially appealing. They can be\nused to identify irrelevant variability and help to understand critical\nprocesses underlying high-dimensional datasets. Additionally, we subjected our\ndata sets to nonlinear time series analysis, as those are well established\nmethods for results comparison. To investigate the usefulness of dimension\nreduction methods, we decided to base our study on a concrete sample set. The\nexample was taken from the domain of systems biology concerning dynamic\nevolution of sub-cellular signaling. Particularly, the dataset relates to the\nyeast pheromone pathway and is studied in-silico with a stochastic model. The\nmodel reconstructs signal propagation stimulated by a mating pheromone. In the\npaper, we elaborate on the reason of multidimensional analysis problem in the\ncontext of molecular signaling, and next, we introduce the model of choice,\nsimulation details and obtained time series dynamics. A description of used\nmethods followed by a discussion of results and their biological interpretation\nfinalize the paper.\n",
"title": "Building Models for Biopathway Dynamics Using Intrinsic Dimensionality Analysis"
}
| null | null | null | null | true | null |
17654
| null |
Default
| null | null |
null |
{
"abstract": " The planar linear restricted four-body problem is used in order to determine\nthe Newton-Raphson basins of convergence associated with the equilibrium\npoints. The parametric variation of the position as well as of the stability of\nthe libration points is monitored when the values of the mass parameter $b$ as\nwell as of the angular velocity $\\omega$ vary in predefined intervals. The\nregions on the configuration $(x,y)$ plane occupied by the basins of attraction\nare revealed using the multivariate version of the Newton-Raphson iterative\nscheme. The correlations between the attracting domains of the equilibrium\npoints and the corresponding number of iterations needed for obtaining the\ndesired accuracy are also illustrated. We perform a thorough and systematic\nnumerical investigation by demonstrating how the parameters $b$ and $\\omega$\ninfluence the shape, the geometry and of course the fractality of the\nconverging regions. Our numerical outcomes strongly indicate that these two\nparameters are indeed two of the most influential factors in this dynamical\nsystem.\n",
"title": "Equilibrium points and basins of convergence in the linear restricted four-body problem with angular velocity"
}
| null | null | null | null | true | null |
17655
| null |
Default
| null | null |
null |
{
"abstract": " We investigate the mechanical properties of amorphous polymers by means of\ncoarse-grained simulations and nonaffine lattice dynamics theory. A small\nincrease of polymer chain bending stiffness leads first to softening of the\nmaterial, while hardening happens only upon further strengthening of the\nbackbones. This nonmonotonic variation of the storage modulus $G'$ with bending\nstiffness is caused by a competition between additional resistance to\ndeformation offered by stiffer backbones and decreased density of the material\ndue to a necessary decrease in monomer-monomer coordination. This\ncounter-intuitive finding suggests that the strength of polymer glasses may in\nsome circumstances be enhanced by softening the bending of constituent chains.\n",
"title": "Nonmonotonic dependence of polymer glass mechanical response on chain bending stiffness"
}
| null | null | null | null | true | null |
17656
| null |
Default
| null | null |
null |
{
"abstract": " Skin cancer is a major public health problem, as is the most common type of\ncancer and represents more than half of cancer diagnoses worldwide. Early\ndetection influences the outcome of the disease and motivates our work. We\ninvestigate the composition of CNN committees and data augmentation for the the\nISBI 2017 Melanoma Classification Challenge (named Skin Lesion Analysis towards\nMelanoma Detection) facing the peculiarities of dealing with such a small,\nunbalanced, biological database. For that, we explore committees of\nConvolutional Neural Networks trained over the ISBI challenge training dataset\nartificially augmented by both classical image processing transforms and image\nwarping guided by specialist knowledge about the lesion axis and improve the\nfinal classifier invariance to common melanoma variations.\n",
"title": "Convolutional Neural Network Committees for Melanoma Classification with Classical And Expert Knowledge Based Image Transforms Data Augmentation"
}
| null | null |
[
"Computer Science"
] | null | true | null |
17657
| null |
Validated
| null | null |
null |
{
"abstract": " This article introduces the notion of arbitrage for a situation involving a\ncollection of investments and a payoff matrix describing the return to an\ninvestor of each investment under each of a set of possible scenarios. We\nexplain the Arbitrage Theorem, discuss its geometric meaning, and show its\nequivalence to Farkas' Lemma. We then ask a seemingly innocent question: given\na random payoff matrix, what is the probability of an arbitrage opportunity?\nThis question leads to some interesting geometry involving hyperplane\narrangements and related topics.\n",
"title": "Arbitrage and Geometry"
}
| null | null | null | null | true | null |
17658
| null |
Default
| null | null |
null |
{
"abstract": " We define a class of surfaces and surface pairs corresponding to the ADE root\nlattices and construct compactifications of their moduli spaces, generalizing\nLosev-Manin spaces of curves.\n",
"title": "ADE surfaces and their moduli"
}
| null | null | null | null | true | null |
17659
| null |
Default
| null | null |
null |
{
"abstract": " An efficient descriptor model for fast screening of potential materials for\nsolar cell applications is presented. It works for both excitonic and\nnon-excitonic solar cells materials, and in addition to the energy gap it\nincludes the absorption spectrum ($\\alpha(E)$) of the material. The charge\ntransport properties of the explored materials are modeled using the\ncharacteristic diffusion length ($L_{d}$) determined for the respective family\nof compounds. The presented model surpasses the widely used Scharber model\ndeveloped for bulk-heterojunction solar cells [Scharber \\textit{et al.,\nAdvanced Materials}, 2006, Vol. 18, 789]. Using published experimental data, we\nshow that the presented model is more accurate in predicting the achievable\nefficiencies. Although the focus of this work is on organic photovoltaics\n(OPV), for which the original Scharber model was developed, the model presented\nhere is applicable also to other solar cell technologies. To model both\nexcitonic and non-excitonic systems, two different sets of parameters are used\nto account for the different modes of operation. The analysis of the presented\ndescriptor model clearly shows the benefit of including $\\alpha(E)$ and $L_{d}$\nin view of improved screening results.\n",
"title": "An Efficient Descriptor Model for Designing Materials for Solar Cells"
}
| null | null | null | null | true | null |
17660
| null |
Default
| null | null |
null |
{
"abstract": " We prove, combinatorially, that the product of a Schubert polynomial by a\nStanley symmetric polynomial is a truncated Schubert polynomial. Using Monk's\nrule, we derive a nonnegative combinatorial formula for the Schubert polynomial\nexpansion of a truncated Schubert polynomial. Combining these results, we give\na nonnegative combinatorial rule for the product of a Schubert and a Schur\npolynomial in the Schubert basis.\n",
"title": "Multiplication of a Schubert polynomial by a Stanley symmetric polynomial"
}
| null | null | null | null | true | null |
17661
| null |
Default
| null | null |
null |
{
"abstract": " Topological nodal line (DNL) semimetals, formed by a closed loop of the\ninverted bands in the bulk, result in the nearly flat drumhead-like surface\nstates with a high electronic density near the Fermi level. The high catalytic\nactive sites associated with the high electronic densities, the good carrier\nmobility, and the proper thermodynamic stabilities with $\\Delta\nG_{H^*}$$\\approx$0 are currently the prerequisites to seek the alternative\ncandidates to precious platinum for catalyzing electrochemical hydrogen (HER)\nproduction from water. Within this context, it is natural to consider whether\nor not the DNLs are a good candidate for the HER because its non-trivial\nsurface states provide a robust platform to activate possibly chemical\nreactions. Here, through first-principles calculations we reported on a new DNL\nTiSi-type family with a closed Dirac nodal line consisting of the linear band\ncrossings in the $k_y$ = 0 plane. The hydrogen adsorption on the (010) and\n(110) surfaces yields the $\\Delta G_{H^*}$ to be almost zero. The topological\ncharge carries have been revealed to participate in this HER. The results are\nhighlighting that TiSi not only is a promising catalyst for the HER but also\npaves a new routine to design topological quantum catalyst utilizing the\ntopological DNL-induced surface bands as active sites, rather than edge sites-,\nvacancy-, dopant-, strain-, or heterostructure-created active sites.\n",
"title": "Topological nodal line states and a potential catalyst of hydrogen evolution in the TiSi family"
}
| null | null | null | null | true | null |
17662
| null |
Default
| null | null |
null |
{
"abstract": " Variational inference is a popular technique to approximate a possibly\nintractable Bayesian posterior with a more tractable one. Recently, boosting\nvariational inference has been proposed as a new paradigm to approximate the\nposterior by a mixture of densities by greedily adding components to the\nmixture. However, as is the case with many other variational inference\nalgorithms, its theoretical properties have not been studied. In the present\nwork, we study the convergence properties of this approach from a modern\noptimization viewpoint by establishing connections to the classic Frank-Wolfe\nalgorithm. Our analyses yields novel theoretical insights regarding the\nsufficient conditions for convergence, explicit rates, and algorithmic\nsimplifications. Since a lot of focus in previous works for variational\ninference has been on tractability, our work is especially important as a much\nneeded attempt to bridge the gap between probabilistic models and their\ncorresponding theoretical properties.\n",
"title": "Boosting Variational Inference: an Optimization Perspective"
}
| null | null | null | null | true | null |
17663
| null |
Default
| null | null |
null |
{
"abstract": " Monolayers of transition metal dichalcogenides (TMDCs) exhibit excellent\nelectronic and optical properties. However, the performance of these\ntwo-dimensional (2D) devices are often limited by the large resistance offered\nby the metal contact interface. Till date, the carrier injection mechanism from\nmetal to 2D TMDC layers remains unclear, with widely varying reports of\nSchottky barrier height (SBH) and contact resistance (Rc), particularly in the\nmonolayer limit. In this work, we use a combination of theory and experiments\nin Au and Ni contacted monolayer MoS2 device to conclude the following points:\n(i) the carriers are injected at the source contact through a cascade of two\npotential barriers - the barrier heights being determined by the degree of\ninteraction between the metal and the TMDC layer; (ii) the conventional\nRichardson equation becomes invalid due to the multi-dimensional nature of the\ninjection barriers, and using Bardeen-Tersoff theory, we derive the appropriate\nform of the Richardson equation that describes such composite barrier; (iii) we\npropose a novel transfer length method (TLM) based SBH extraction methodology,\nto reliably extract SBH by eliminating any confounding effect of temperature\ndependent channel resistance variation; (iv) we derive the Landauer limit of\nthe contact resistance achievable in such devices. A comparison of the limits\nwith the experimentally achieved contact resistance reveals plenty of room for\ntechnological improvements.\n",
"title": "Nature of carrier injection in metal/2D semiconductor interface and its implications to the limits of contact resistance"
}
| null | null | null | null | true | null |
17664
| null |
Default
| null | null |
null |
{
"abstract": " Exact solutions for laminar stratified flows of Newtonian/non-Newtonian\nshear-thinning fluids in horizontal and inclined channels are presented. An\niterative algorithm is proposed to compute the laminar solution for the general\ncase of a Carreau non-Newtonian fluid. The exact solution is used to study the\neffect of the rheology of the shear-thinning liquid on two-phase flow\ncharacteristics considering both gas/liquid and liquid/liquid systems.\nConcurrent and counter-current inclined systems are investigated, including the\nmapping of multiple solution boundaries. Aspects relevant to practical\napplications are discussed, such as the insitu hold-up, or lubrication effects\nachieved by adding a less viscous phase. A characteristic of this family of\nsystems is that, even if the liquid has a complex rheology (Carreau fluid), the\ntwo-phase stratified flow can behave like the liquid is Newtonian for a wide\nrange of operational conditions. The capability of the two-fluid model to yield\nsatisfactory predictions in the presence of shear-thinning liquids is tested,\nand an algorithm is proposed to a priori predict if the Newtonian (zero shear\nrate viscosity) behaviour arises for a given operational conditions in order to\navoid large errors in the predictions of flow characteristics when the\npower-law is considered for modelling the shear-thinning behaviour. Two-fluid\nmodel closures implied by the exact solution and the effect of a turbulent gas\nlayer are also addressed.\n",
"title": "Characteristics of stratified flows of Newtonian/non-Newtonian shear-thinning fluids"
}
| null | null | null | null | true | null |
17665
| null |
Default
| null | null |
null |
{
"abstract": " A large class of machine learning techniques requires the solution of\noptimization problems involving spectral functions of parametric matrices, e.g.\nlog-determinant and nuclear norm. Unfortunately, computing the gradient of a\nspectral function is generally of cubic complexity, as such gradient descent\nmethods are rather expensive for optimizing objectives involving the spectral\nfunction. Thus, one naturally turns to stochastic gradient methods in hope that\nthey will provide a way to reduce or altogether avoid the computation of full\ngradients. However, here a new challenge appears: there is no straightforward\nway to compute unbiased stochastic gradients for spectral functions. In this\npaper, we develop unbiased stochastic gradients for spectral-sums, an important\nsubclass of spectral functions. Our unbiased stochastic gradients are based on\ncombining randomized trace estimators with stochastic truncation of the\nChebyshev expansions. A careful design of the truncation distribution allows us\nto offer distributions that are variance-optimal, which is crucial for fast and\nstable convergence of stochastic gradient methods. We further leverage our\nproposed stochastic gradients to devise stochastic methods for objective\nfunctions involving spectral-sums, and rigorously analyze their convergence\nrate. The utility of our methods is demonstrated in numerical experiments.\n",
"title": "Stochastic Chebyshev Gradient Descent for Spectral Optimization"
}
| null | null | null | null | true | null |
17666
| null |
Default
| null | null |
null |
{
"abstract": " The covariant canonical formalism is a covariant extension of the traditional\ncanonical formalism of fields. In contrast to the traditional canonical theory,\nit has a remarkable feature that canonical equations of gauge theories or\ngravity are not only manifestly Lorentz covariant but also gauge covariant or\ndiffeomorphism covariant. A mathematical peculiarity of the covariant canonical\nformalism is that its canonical coordinates are differential forms on a\nmanifold. In the present paper, we find a natural Poisson bracket of this new\ncanonical theory, and study symplectic structure behind it. The phase space of\nthe theory is identified with a ringed space with the structure sheaf of the\ngraded algebra of \"differentiable\" differential forms on the manifold. The\nPoisson and the symplectic structure we found can be even or odd, depending on\nthe dimension of the manifold. Our Poisson structure is an example of physical\napplication of Poisson structure defined on the graded algebra of differential\nforms.\n",
"title": "Poisson Bracket and Symplectic Structure of Covariant Canonical Formalism of Fields"
}
| null | null | null | null | true | null |
17667
| null |
Default
| null | null |
null |
{
"abstract": " We study cascading failures in a system comprising interdependent\nnetworks/systems, in which nodes rely on other nodes both in the same system\nand in other systems to perform their function. The (inter-)dependence among\nnodes is modeled using a dependence graph, where the degree vector of a node\ndetermines the number of other nodes it can potentially cause to fail in each\nsystem through aforementioned dependency. In particular, we examine the impact\nof the variability and dependence properties of node degrees on the probability\nof cascading failures. We show that larger variability in node degrees hampers\nwidespread failures in the system, starting with random failures. Similarly,\npositive correlations in node degrees make it harder to set off an epidemic of\nfailures, thereby rendering the system more robust against random failures.\n",
"title": "Cascading Failures in Interdependent Systems: Impact of Degree Variability and Dependence"
}
| null | null | null | null | true | null |
17668
| null |
Default
| null | null |
null |
{
"abstract": " For any geodesic current we associated a quasi-metric space. For a subclass\nof geodesic currents, called filling, it defines a metric and we study the\ncritical exponent associated to this space. We show that is is equal to the\nexponential growth rate of the intersection function for closed curves.\n",
"title": "Critical exponent for geodesic currents"
}
| null | null |
[
"Mathematics"
] | null | true | null |
17669
| null |
Validated
| null | null |
null |
{
"abstract": " Trivial events are ubiquitous in human to human conversations, e.g., cough,\nlaugh and sniff. Compared to regular speech, these trivial events are usually\nshort and unclear, thus generally regarded as not speaker discriminative and so\nare largely ignored by present speaker recognition research. However, these\ntrivial events are highly valuable in some particular circumstances such as\nforensic examination, as they are less subjected to intentional change, so can\nbe used to discover the genuine speaker from disguised speech. In this paper,\nwe collect a trivial event speech database that involves 75 speakers and 6\ntypes of events, and report preliminary speaker recognition results on this\ndatabase, by both human listeners and machines. Particularly, the deep feature\nlearning technique recently proposed by our group is utilized to analyze and\nrecognize the trivial events, which leads to acceptable equal error rates\n(EERs) despite the extremely short durations (0.2-0.5 seconds) of these events.\nComparing different types of events, 'hmm' seems more speaker discriminative.\n",
"title": "Human and Machine Speaker Recognition Based on Short Trivial Events"
}
| null | null | null | null | true | null |
17670
| null |
Default
| null | null |
null |
{
"abstract": " In this paper, we investigate the Casacore Table Data System (CTDS) used in\nthe casacore and CASA libraries, and methods to parallelize it. CTDS provides a\nstorage manager plugin mechanism for third-party devel- opers to design and\nimplement their own CTDS storage managers. Hav- ing this in mind, we looked\ninto various storage backend techniques that can possibly enable parallel I/O\nfor CTDS by implementing new storage managers. After carrying on benchmarks\nshowing the excellent parallel I/O throughput of the Adaptive IO System\n(ADIOS), we implemented an ADIOS based parallel CTDS storage manager. We then\napplied the CASA MSTransform frequency split task to verify the ADIOS Storage\nManager. We also ran a series of performance tests to examine the I/O\nthroughput in a massively parallel scenario.\n",
"title": "AdiosStMan: Parallelizing Casacore Table Data System Using Adaptive IO System"
}
| null | null |
[
"Computer Science",
"Physics"
] | null | true | null |
17671
| null |
Validated
| null | null |
null |
{
"abstract": " We report the experimental observation of the filamentation effect in gas\ndevices designed for X-ray Free-electron Lasers. The measurements were carried\nout at the Linac Coherent Light Source on the X-ray Correlation Spectroscopy\n(XCS) instrument using a Two-bunch FEL beam at 6.5 keV with 122.5 ns separation\npassing through an Argon gas cell. The relative intensities of the two pulses\nof the Two-bunch beam were measured, after and before the gas cell, from the\nX-ray scattering off thin targets by using fast diodes with sufficient temporal\nresolution. It was found that the after-to-before ratio of the intensities of\nthe second pulse was consistently higher than that of the first pulse,\nrevealing lower effective attenuation of the gas cell due to the heating and\nsubsequent gas density reduction in the beam path by the first pulse. This\nmeasurement is important in guiding the design and/or mitigating the adverse\neffect in gas devices for high repetition-rate FELs such as the LCLS-II and the\nEuropean XFEL or other future high repetition-rate upgrade to existing FEL\nfacilities\n",
"title": "Direct Experimental Observation of the Gas Filamentation Effect using a Two-bunch X-ray FEL Beam"
}
| null | null | null | null | true | null |
17672
| null |
Default
| null | null |
null |
{
"abstract": " In absence of a lens to form an image, incoherent or partially coherent light\nscattering off an obstructive or reflective object forms a broad intensity\ndistribution in the far field with only feeble spatial features. We show here\nthat measuring the complex spatial coherence function can help in the\nidentification of the size and location of a one-dimensional object placed in\nthe path of a partially coherent light source. The complex coherence function\nis measured in the far field through wavefront sampling, which is performed via\ndynamically reconfigurable slits implemented on a digital micromirror device\n(DMD). The impact of an object -- parameterized by size and location -- that\neither intercepts or reflects incoherent light is studied. The experimental\nresults show that measuring the spatial coherence function as a function of the\nseparation between two slits located symmetrically around the optical axis can\nidentify the object transverse location and angle subtended from the detection\nplane (the ratio of the object width to the axial distance from the detector).\nThe measurements are in good agreement with numerical simulations of a forward\nmodel based on Fresnel propagators. The rapid refresh rate of DMDs may enable\nreal-time operation of such a lensless coherency imaging scheme.\n",
"title": "Coherence measurements of scattered incoherent light for lensless identification of an object's location and size"
}
| null | null | null | null | true | null |
17673
| null |
Default
| null | null |
null |
{
"abstract": " Multiview video supports observing a scene from different viewpoints. The\nJoint Video Team (JVT) developed H.264/MVC to enhance the compression\nefficiency for multiview video, however, MVC encoded multiview video (MVC\nvideo) still requires high bitrates for transmission. This paper investigates\nlive MVC video streaming over Peer-to-Peer (P2P) networks. The goal is to\nminimize the server bandwidth costs whist ensuring high streaming quality to\npeers. MVC employs intra-view and inter-view prediction structures, which leads\nto a complicated layer dependency relationship. As the peers' outbound\nbandwidth is shared while supplying all the MVC video layers, the bandwidth\nallocation to one MVC layer affects the available outbound bandwidth of the\nother layers. To optimise the utilisation of the peers' outbound bandwidth for\nproviding video layers, a maximum flow based model is proposed which considers\nthe MVC video layer dependency and the layer supplying relationship between\npeers. Based on the model, a layer dependency aware live MVC video streaming\nmethod over a BitTorrent-like P2P network is proposed, named MVP2P. The key\ncomponents of MVP2P include a chunk scheduling strategy and a peer selection\nstrategy for receiving peers, and a bandwidth scheduling algorithm for\nsupplying peers. To evaluate the efficiency of the proposed solution, MVP2P is\ncompared with existing methods considering the constraints of peer bandwidth,\npeer numbers, view switching rates, and peer churns. The test results show that\nMVP2P significantly outperforms the existing methods.\n",
"title": "MVP2P: Layer-Dependency-Aware Live MVC Video Streaming over Peer-to-Peer Networks"
}
| null | null | null | null | true | null |
17674
| null |
Default
| null | null |
null |
{
"abstract": " The objective of the present work is to construct a sound mathematical,\nnumerical and computational framework relevant to blood flow simulations and to\nassess it through a careful validation against experimental data. We perform\nsimulations of a benchmark proposed by the FDA for fluid flow in an idealized\nmedical device, under different flow regimes. The results are evaluated using\nmetrics proposed in the literature and the findings are in very good agreement\nwith the validation experiment.\n",
"title": "High order finite element simulations for fluid dynamics validated by experimental data from the fda benchmark nozzle model"
}
| null | null | null | null | true | null |
17675
| null |
Default
| null | null |
null |
{
"abstract": " We propose a simple technique for encouraging generative RNNs to plan ahead.\nWe train a \"backward\" recurrent network to generate a given sequence in reverse\norder, and we encourage states of the forward model to predict cotemporal\nstates of the backward model. The backward network is used only during\ntraining, and plays no role during sampling or inference. We hypothesize that\nour approach eases modeling of long-term dependencies by implicitly forcing the\nforward states to hold information about the longer-term future (as contained\nin the backward states). We show empirically that our approach achieves 9%\nrelative improvement for a speech recognition task, and achieves significant\nimprovement on a COCO caption generation task.\n",
"title": "Twin Networks: Matching the Future for Sequence Generation"
}
| null | null | null | null | true | null |
17676
| null |
Default
| null | null |
null |
{
"abstract": " Loosely speaking, the Shannon entropy rate is used to gauge a stochastic\nprocess' intrinsic randomness; the statistical complexity gives the cost of\npredicting the process. We calculate, for the first time, the entropy rate and\nstatistical complexity of stochastic processes generated by finite unifilar\nhidden semi-Markov models---memoryful, state-dependent versions of renewal\nprocesses. Calculating these quantities requires introducing novel mathematical\nobjects ({\\epsilon}-machines of hidden semi-Markov processes) and new\ninformation-theoretic methods to stochastic processes.\n",
"title": "Structure and Randomness of Continuous-Time Discrete-Event Processes"
}
| null | null | null | null | true | null |
17677
| null |
Default
| null | null |
null |
{
"abstract": " Aspects of the preparation process and performance degradation are two major\nproblems of photocathodes. The lack of a means for dynamic quantum efficiency\nmeasurements results in the inability to observe the inhomogeneity of the\ncathode surface by fine structural analysis and in real time.Here we present a\nsimple and scalable technique for in situ real-time quantum efficiency\ndiagnosis. An incoherent light source provides uniform illumination on the\ncathode surface, and solenoid magnets are used as lens for focusing and imaging\nthe emitted electron beam on a downstream scintillator screen, which converts\nthe quantum efficiency information into fluorescence intensity distribution.\nThe microscopic discontinuity and the dynamic changes of the quantum efficiency\nof a gallium arsenide photocathode are observed at a resolution of a few\nmicrons. An unexpected uneven decrease of the quantum efficiency is also\nrecorded. The work demonstrates a new observation method for photoemission\nmaterials research.\n",
"title": "In situ high resolution real-time quantum efficiency imaging for photocathodes"
}
| null | null | null | null | true | null |
17678
| null |
Default
| null | null |
null |
{
"abstract": " A mixed manna contains goods (that everyone likes), bads (that everyone\ndislikes), as well as items that are goods to some agents, but bads or satiated\nto others.\nIf all items are goods and utility functions are homothetic, concave (and\nmonotone), the Competitive Equilibrium with Equal Incomes maximizes the Nash\nproduct of utilities: hence it is welfarist (determined utility-wise by the\nfeasible set of profiles), single-valued and easy to compute.\nWe generalize the Gale-Eisenberg Theorem to a mixed manna. The Competitive\ndivision is still welfarist and related to the product of utilities or\ndisutilities. If the zero utility profile (before any manna) is Pareto\ndominated, the competitive profile is unique and still maximizes the product of\nutilities. If the zero profile is unfeasible, the competitive profiles are the\ncritical points of the product of disutilities on the efficiency frontier, and\nmultiplicity is pervasive. In particular the task of dividing a mixed manna is\neither good news for everyone, or bad news for everyone.\nWe refine our results in the practically important case of linear\npreferences, where the axiomatic comparison between the division of goods and\nthat of bads is especially sharp. When we divide goods and the manna improves,\neveryone weakly benefits under the competitive rule; but no reasonable rule to\ndivide bads can be similarly Resource Monotonic. Also, the much larger set of\nNon Envious and Efficient divisions of bads can be disconnected so that it will\nadmit no continuous selection.\n",
"title": "Competitive division of a mixed manna"
}
| null | null | null | null | true | null |
17679
| null |
Default
| null | null |
null |
{
"abstract": " How can we explain the predictions of a black-box model? In this paper, we\nuse influence functions -- a classic technique from robust statistics -- to\ntrace a model's prediction through the learning algorithm and back to its\ntraining data, thereby identifying training points most responsible for a given\nprediction. To scale up influence functions to modern machine learning\nsettings, we develop a simple, efficient implementation that requires only\noracle access to gradients and Hessian-vector products. We show that even on\nnon-convex and non-differentiable models where the theory breaks down,\napproximations to influence functions can still provide valuable information.\nOn linear models and convolutional neural networks, we demonstrate that\ninfluence functions are useful for multiple purposes: understanding model\nbehavior, debugging models, detecting dataset errors, and even creating\nvisually-indistinguishable training-set attacks.\n",
"title": "Understanding Black-box Predictions via Influence Functions"
}
| null | null | null | null | true | null |
17680
| null |
Default
| null | null |
null |
{
"abstract": " We study analytically and numerically the optical analogue of the\nJackiw-Rebbi states in quantum field theory. These solutions exist at the\ninterface of two binary waveguide arrays which are described by two Dirac\nequations with opposite sign masses. We show that these special states are\ntopologically robust not only in the linear regime, but also in nonlinear\nregimes (with both focusing and de-focusing nonlinearity). We also reveal that\none can generate the Jackiw-Rebbi states starting from Dirac solitons.\n",
"title": "Linear and nonlinear photonic Jackiw-Rebbi states in waveguide arrays"
}
| null | null | null | null | true | null |
17681
| null |
Default
| null | null |
null |
{
"abstract": " Progress in science has advanced the development of human society across\nhistory, with dramatic revolutions shaped by information theory, genetic\ncloning, and artificial intelligence, among the many scientific achievements\nproduced in the 20th century. However, the way that science advances itself is\nmuch less well-understood. In this work, we study the evolution of scientific\ndevelopment over the past century by presenting an anatomy of 89 million\ndigitalized papers published between 1900 and 2015. We find that science has\nbenefited from the shift from individual work to collaborative effort, with\nover 90% of the world-leading innovations generated by collaborations in this\ncentury, nearly four times higher than they were in the 1900s. We discover that\nrather than the frequent myopic- and self-referencing that was common in the\nearly 20th century, modern scientists instead tend to look for literature\nfurther back and farther around. Finally, we also observe the globalization of\nscientific development from 1900 to 2015, including 25-fold and 7-fold\nincreases in international collaborations and citations, respectively, as well\nas a dramatic decline in the dominant accumulation of citations by the US, the\nUK, and Germany, from ~95% to ~50% over the same period. Our discoveries are\nmeant to serve as a starter for exploring the visionary ways in which science\nhas developed throughout the past century, generating insight into and an\nimpact upon the current scientific innovations and funding policies.\n",
"title": "A Century of Science: Globalization of Scientific Collaborations, Citations, and Innovations"
}
| null | null | null | null | true | null |
17682
| null |
Default
| null | null |
null |
{
"abstract": " Each family $\\mathcal{M}$ of means has a natural, partial order (point-wise\norder), that is $M \\le N$ iff $M(x) \\le N(x)$ for all admissible $x$.\nIn this setting we can introduce the notion of interval-type set (a subset\n$\\mathcal{I} \\subset \\mathcal{M}$ such that whenever $M \\le P \\le N$ for some\n$M,\\,N \\in \\mathcal{I}$ and $P \\in \\mathcal{M}$ then $P \\in \\mathcal{I}$). For\nexample, in the case of power means there exists a natural isomorphism between\ninterval-type sets and intervals contained in real numbers. Nevertheless there\nappear a number of interesting objects for a families which cannot be linearly\nordered.\nIn the present paper we consider this property for Gini means and Hardy\nmeans. Moreover some results concerning $L^\\infty$ metric among (abstract)\nmeans will be obtained.\n",
"title": "Interval-type theorems concerning means"
}
| null | null | null | null | true | null |
17683
| null |
Default
| null | null |
null |
{
"abstract": " We propose a fully distributed actor-critic algorithm approximated by deep\nneural networks, named \\textit{Diff-DAC}, with application to single-task and\nto average multitask reinforcement learning (MRL). Each agent has access to\ndata from its local task only, but it aims to learn a policy that performs well\non average for the whole set of tasks. During the learning process, agents\ncommunicate their value-policy parameters to their neighbors, diffusing the\ninformation across the network, so that they converge to a common policy, with\nno need for a central node. The method is scalable, since the computational and\ncommunication costs per agent grow with its number of neighbors. We derive\nDiff-DAC's from duality theory and provide novel insights into the standard\nactor-critic framework, showing that it is actually an instance of the dual\nascent method that approximates the solution of a linear program. Experiments\nsuggest that Diff-DAC can outperform the single previous distributed MRL\napproach (i.e., Dist-MTLPS) and even the centralized architecture.\n",
"title": "Diff-DAC: Distributed Actor-Critic for Average Multitask Deep Reinforcement Learning"
}
| null | null |
[
"Computer Science",
"Statistics"
] | null | true | null |
17684
| null |
Validated
| null | null |
null |
{
"abstract": " We describe the structure of Hausdorff locally compact semitopological\n$0$-bisimple inverse $\\omega$-semigroups with compact maximal subgroups. In\nparticular, we show that a Hausdorff locally compact semitopological\n$0$-bisimple inverse $\\omega$-semigroup with a compact maximal subgroup is\neither compact or topologically isomorphic to the topological sum of its\n$\\mathscr{H}$-classes. We describe the structure of Hausdorff locally compact\nsemitopological $0$-bisimple inverse $\\omega$-semigroups with a monothetic\nmaximal subgroups. In particular we prove the dichotomy for $T_1$ locally\ncompact semitopological Reilly semigroup\n$\\left(\\textbf{B}(\\mathbb{Z}_{+},\\theta)^0,\\tau\\right)$ with adjoined zero and\nwith a non-annihilating homomorphism $\\theta\\colon \\mathbb{Z}_{+}\\to\n\\mathbb{Z}_{+}$: $\\left(\\textbf{B}(\\mathbb{Z}_{+},\\theta)^0,\\tau\\right)$ is\neither compact or discrete. At the end we discuss on the remainder under the\nclosure of the discrete Reilly semigroup $\\textbf{B}(\\mathbb{Z}_{+},\\theta)^0$\nin a semitopological semigroup.\n",
"title": "On locally compact semitopological $0$-bisimple inverse $ω$-semigroups"
}
| null | null | null | null | true | null |
17685
| null |
Default
| null | null |
null |
{
"abstract": " Electrons that are confined to a single Landau level in a two dimensional\nelectron gas realize the effects of strong electron-electron repulsion in its\npurest form. The kinetic energy of individual electrons is completely quenched\nand all physical properties are dictated solely by many-body effects. A\nremarkable consequence is the emergence of new quasiparticles with fractional\ncharge and exotic quantum statistics of which the most exciting ones are\nnon-Abelian quasiparticles. A non-integer quantized thermal Hall conductance\n$\\kappa_{xy}$ (in units of temperature times the universal constant $\\pi^2\nk_B^2 /3 h$; $h$ is the Planck constant and $k_B$ the Boltzmann constant)\nnecessitates the existence of such quasiparticles. It has been predicted, and\nverified numerically, that such states are realized in the clean half-filled\nfirst Landau level of electrons with Coulomb repulsion, with $\\kappa_{xy}$\nbeing either $3/2$ or $7/2$. Excitingly, a recent experiment has indeed\nobserved a half-integer value, which was measured, however, to be\n$\\kappa_{xy}=5/2$. We resolve this contradiction within a picture where smooth\ndisorder results in the formation of mesoscopic puddles with locally\n$\\kappa_{xy}=3/2$ or $7/2$. Interactions between these puddles generate a\ncoherent macroscopic state, which is reflected in an extended plateau with\nquantized $\\kappa_{xy}=5/2$. The topological properties of quasiparticles at\nlarge distances are determined by the macroscopic phase, and not by the\nmicroscopic puddle where they reside. In principle, the same mechanism might\nalso allow non-Abelian quasiparticles to emerge from a system comprised of\nmicroscopic Abelian puddles.\n",
"title": "Theory of Disorder-Induced Half-Integer Thermal Hall Conductance"
}
| null | null | null | null | true | null |
17686
| null |
Default
| null | null |
null |
{
"abstract": " Over the last decades, numerous security and privacy issues in all three\nactive mobile network generations have been revealed that threaten users as\nwell as network providers. In view of the newest generation (5G) currently\nunder development, we now have the unique opportunity to identify research\ndirections for the next generation based on existing security and privacy\nissues as well as already proposed defenses. This paper aims to unify security\nknowledge on mobile phone networks into a comprehensive overview and to derive\npressing open research questions. To achieve this systematically, we develop a\nmethodology that categorizes known attacks by their aim, proposed defenses,\nunderlying causes, and root causes. Further, we assess the impact and the\nefficacy of each attack and defense. We then apply this methodology to existing\nliterature on attacks and defenses in all three network generations. By doing\nso, we identify ten causes and four root causes of attacks. Mapping the attacks\nto proposed defenses and suggestions for the 5G specification enables us to\nuncover open research questions and challenges for the development of\nnext-generation mobile networks. The problems of unsecured pre-authentication\ntraffic and jamming attacks exist across all three mobile generations. They\nshould be addressed in the future, in particular, to wipe out the class of\ndowngrade attacks and, thereby, strengthen the users' privacy. Further advances\nare needed in the areas of inter-operator protocols as well as secure baseband\nimplementations. Additionally, mitigations against denial-of-service attacks by\nsmart protocol design represent an open research question.\n",
"title": "On Security Research Towards Future Mobile Network Generations"
}
| null | null | null | null | true | null |
17687
| null |
Default
| null | null |
null |
{
"abstract": " In this review we discuss how channel simulation can be used to simplify the\nmost general protocols of quantum parameter estimation, where unlimited\nentanglement and adaptive joint operations may be employed. Whenever the\nunknown parameter encoded in a quantum channel is completely transferred in an\nenvironmental program state simulating the channel, the optimal adaptive\nestimation cannot beat the standard quantum limit. In this setting, we\nelucidate the crucial role of quantum teleportation as a primitive operation\nwhich allows one to completely reduce adaptive protocols over suitable\nteleportation-covariant channels and derive matching upper and lower bounds for\nparameter estimation. For these channels, we may express the quantum Cramér\nRao bound directly in terms of their Choi matrices. Our review considers both\ndiscrete- and continuous-variable systems, also presenting some new results for\nbosonic Gaussian channels using an alternative sub-optimal simulation. It is an\nopen problem to design simulations for quantum channels that achieve the\nHeisenberg limit.\n",
"title": "Channel Simulation in Quantum Metrology"
}
| null | null | null | null | true | null |
17688
| null |
Default
| null | null |
null |
{
"abstract": " A non-parametric method for ranking stock indices according to their mutual\ncausal influences is presented. Under the assumption that indices reflect the\nunderlying economy of a country, such a ranking indicates which countries exert\nthe most economic influence in an examined subset of the global economy. The\nproposed method represents the indices as nodes in a directed graph, where the\nedges' weights are estimates of the pair-wise causal influences, quantified\nusing the directed information functional. This method facilitates using a\nrelatively small number of samples from each index. The indices are then ranked\naccording to their net-flow in the estimated graph (sum of the incoming weights\nsubtracted from the sum of outgoing weights). Daily and minute-by-minute data\nfrom nine indices (three from Asia, three from Europe and three from the US)\nwere analyzed. The analysis of daily data indicates that the US indices are the\nmost influential, which is consistent with intuition that the indices\nrepresenting larger economies usually exert more influence. Yet, it is also\nshown that an index representing a small economy can strongly influence an\nindex representing a large economy if the smaller economy is indicative of a\nlarger phenomenon. Finally, it is shown that while inter-region interactions\ncan be captured using daily data, intra-region interactions require more\nfrequent samples.\n",
"title": "Ranking Causal Influence of Financial Markets via Directed Information Graphs"
}
| null | null | null | null | true | null |
17689
| null |
Default
| null | null |
null |
{
"abstract": " Plastic deformation of metallic glasses performed well below the glass\ntransition temperature leads to the formation of shear bands as a result of\nshear localization. It is believed that shear banding originates from\nindividual stress concentrators having quadrupolar symmetry. To elucidate the\nunderlying mechanisms of shear band formation, microstructural investigations\nwere carried out on sheared zones using transmission electron microscopy. Here\nwe show evidence of a characteristic signature present in shear bands\nmanifested in the form of sinusoidal density variations. We present an\nanalytical solution for the observed post-deformation state derived from\ncontinuum mechanics using an alignment of quadrupolar stress field\nperturbations for the plastic events. Since we observe qualitatively similar\nfeatures for three different types of metallic glasses that span the entire\nrange of characteristic properties of metallic glasses, we conclude that the\nreported deformation behavior is generic for all metallic glasses, and thus has\nfar-reaching consequences for the deformation behavior of amorphous solids in\ngeneral.\n",
"title": "Shear banding in metallic glasses described by alignments of Eshelby quadrupoles"
}
| null | null | null | null | true | null |
17690
| null |
Default
| null | null |
null |
{
"abstract": " This work is closely related to the theories of set estimation and manifold\nestimation.\nOur object of interest is a, possibly lower-dimensional, compact set $S\n\\subset {\\mathbb R}^d$.\nThe general aim is to identify (via stochastic procedures) some qualitative\nor quantitative features of $S$, of geometric or topological character. The\navailable information is just a random sample of points drawn on $S$.\nThe term \"to identify\" means here to achieve a correct answer almost surely\n(a.s.) when the sample size tends to infinity. More specifically the paper aims\nat giving some partial answers to the following questions: is $S$ full\ndimensional? Is $S$ \"close to a lower dimensional set\" $\\mathcal{M}$? If so,\ncan we estimate $\\mathcal{M}$ or some functionals of $\\mathcal{M}$ (in\nparticular, the Minkowski content of $\\mathcal{M}$)? As an important auxiliary\ntool in the answers of these questions, a denoising procedure is proposed in\norder to partially remove the noise in the original data. The theoretical\nresults are complemented with some simulations and graphical illustrations.\n",
"title": "Detection of low dimensionality and data denoising via set estimation techniques"
}
| null | null | null | null | true | null |
17691
| null |
Default
| null | null |
null |
{
"abstract": " Detection of cell nuclei in microscopic images is a challenging research\ntopic, because of limitations in cellular image quality and diversity of\nnuclear morphology, i.e. varying nuclei shapes, sizes, and overlaps between\nmultiple cell nuclei. This has been a topic of enduring interest with promising\nrecent success shown by deep learning methods. These methods train for example\nconvolutional neural networks (CNNs) with a training set of input images and\nknown, labeled nuclei locations. Many of these methods are supplemented by\nspatial or morphological processing. We develop a new approach that we call\nShape Priors with Convolutional Neural Networks (SP-CNN) to perform\nsignificantly enhanced nuclei detection. A set of canonical shapes is prepared\nwith the help of a domain expert. Subsequently, we present a new network\nstructure that can incorporate `expected behavior' of nucleus shapes via two\ncomponents: {\\em learnable} layers that perform the nucleus detection and a\n{\\em fixed} processing part that guides the learning with prior information.\nAnalytically, we formulate a new regularization term that is targeted at\npenalizing false positives while simultaneously encouraging detection inside\ncell nucleus boundary. Experimental results on a challenging dataset reveal\nthat SP-CNN is competitive with or outperforms several state-of-the-art\nmethods.\n",
"title": "Deep Networks with Shape Priors for Nucleus Detection"
}
| null | null | null | null | true | null |
17692
| null |
Default
| null | null |
null |
{
"abstract": " Given a Heegaard splitting of a three-manifold Y, we consider the SL(2,C)\ncharacter variety of the Heegaard surface, and two complex Lagrangians\nassociated to the handlebodies. We focus on the smooth open subset\ncorresponding to irreducible representations. On that subset, the intersection\nof the Lagrangians is an oriented d-critical locus in the sense of Joyce. Bussi\nassociates to such an intersection a perverse sheaf of vanishing cycles. We\nprove that in our setting, the perverse sheaf is an invariant of Y, i.e., it is\nindependent of the Heegaard splitting. The hypercohomology of this sheaf can be\nviewed as a model for (the dual of) SL(2,C) instanton Floer homology. We also\npresent a framed version of this construction, which takes into account\nreducible representations. We give explicit computations for lens spaces and\nBrieskorn spheres, and discuss the connection to the Kapustin-Witten equations\nand Khovanov homology.\n",
"title": "A sheaf-theoretic model for SL(2,C) Floer homology"
}
| null | null | null | null | true | null |
17693
| null |
Default
| null | null |
null |
{
"abstract": " Modeling network traffic is gaining importance in order to counter modern\nthreats of ever increasing sophistication. It is though surprisingly difficult\nand costly to construct reliable classifiers on top of telemetry data due to\nthe variety and complexity of signals that no human can manage to interpret in\nfull. Obtaining training data with sufficiently large and variable body of\nlabels can thus be seen as prohibitive problem. The goal of this work is to\ndetect infected computers by observing their HTTP(S) traffic collected from\nnetwork sensors, which are typically proxy servers or network firewalls, while\nrelying on only minimal human input in model training phase. We propose a\ndiscriminative model that makes decisions based on all computer's traffic\nobserved during predefined time window (5 minutes in our case). The model is\ntrained on collected traffic samples over equally sized time window per large\nnumber of computers, where the only labels needed are human verdicts about the\ncomputer as a whole (presumed infected vs. presumed clean). As part of training\nthe model itself recognizes discriminative patterns in traffic targeted to\nindividual servers and constructs the final high-level classifier on top of\nthem. We show the classifier to perform with very high precision, while the\nlearned traffic patterns can be interpreted as Indicators of Compromise. In the\nfollowing we implement the discriminative model as a neural network with\nspecial structure reflecting two stacked multi-instance problems. The main\nadvantages of the proposed configuration include not only improved accuracy and\nability to learn from gross labels, but also automatic learning of server types\n(together with their detectors) which are typically visited by infected\ncomputers.\n",
"title": "Discriminative models for multi-instance problems with tree-structure"
}
| null | null | null | null | true | null |
17694
| null |
Default
| null | null |
null |
{
"abstract": " Quantum coherence phenomena driven by electronic-vibrational (vibronic)\ninteractions, are being reported in many pulse (e.g. laser) driven chemical and\nbiophysical systems. But what systems-level advantage(s) do such many-body\ncoherences offer to future technologies? We address this question for pulsed\nsystems of general size N, akin to the LHCII aggregates found in green plants.\nWe show that external pulses generate vibronic states containing particular\nmultipartite entanglements, and that such collective vibronic states increase\nthe excitonic transfer efficiency. The strength of these many-body coherences\nand their robustness to decoherence, increase with aggregate size N and do not\nrequire strong electronic-vibrational coupling. The implications for energy and\ninformation transport are discussed.\n",
"title": "Functional advantages offered by many-body coherences in biochemical systems"
}
| null | null |
[
"Physics"
] | null | true | null |
17695
| null |
Validated
| null | null |
null |
{
"abstract": " Recently, a wide range of smart devices are deployed in a variety of\nenvironments to improve the quality of human life. One of the important\nIoT-based applications is smart homes for healthcare, especially for elders.\nIoT-based smart homes enable elders' health to be properly monitored and taken\ncare of. However, elders' privacy might be disclosed from smart homes due to\nnon-fully protected network communication or other reasons. To demonstrate how\nserious this issue is, we introduce in this paper a Privacy Mining Approach\n(PMA) to mine privacy from smart homes by conducting a series of deductions and\nanalyses on sensor datasets generated by smart homes. The experimental results\ndemonstrate that PMA is able to deduce a global sensor topology for a smart\nhome and disclose elders' privacy in terms of their house layouts.\n",
"title": "Privacy Mining from IoT-based Smart Homes"
}
| null | null |
[
"Statistics"
] | null | true | null |
17696
| null |
Validated
| null | null |
null |
{
"abstract": " An element e of an ordered semigroup $(S,\\cdot,\\leq)$ is called an ordered\nidempotent if $e\\leq e^2$. We call an ordered semigroup $S$ idempotent ordered\nsemigroup if every element of $S$ is an ordered idempotent. Every idempotent\nsemigroup is a complete semilattice of rectangular idempotent semigroups and in\nthis way we arrive to many other important classes of idempotent ordered\nsemigroups.\n",
"title": "Idempotent ordered semigroup"
}
| null | null | null | null | true | null |
17697
| null |
Default
| null | null |
null |
{
"abstract": " Let $\\pi$ be a Hecke-Maass cusp form for $SL(3,\\mathbb{Z})$ and\n$\\chi=\\chi_1\\chi_2$ a Dirichlet character with $\\chi_i$ primitive modulo $M_i$.\nSuppose that $M_1$, $M_2$ are primes such that\n$\\max\\{(M|t|)^{1/3+2\\delta/3},M^{2/5}|t|^{-9/20},\nM^{1/2+2\\delta}|t|^{-3/4+2\\delta}\\}(M|t|)^{\\varepsilon}<M_1< \\min\\{\n(M|t|)^{2/5},(M|t|)^{1/2-8\\delta}\\}(M|t|)^{-\\varepsilon}$ for any\n$\\varepsilon>0$, where $M=M_1M_2$, $|t|\\geq 1$ and $0<\\delta< 1/52$. Then we\nhave $$ L\\left(\\frac{1}{2}+it,\\pi\\otimes \\chi\\right)\\ll_{\\pi,\\varepsilon}\n(M|t|)^{3/4-\\delta+\\varepsilon}. $$\n",
"title": "Hybrid bounds for twists of $GL(3)$ $L$-functions"
}
| null | null | null | null | true | null |
17698
| null |
Default
| null | null |
null |
{
"abstract": " It is known that the implied volatility skew of FX options demonstrates a\nstochastic behavior which is called stochastic skew. In this paper we create\nstochastic skew by assuming the spot/instantaneous variance correlation to be\nstochastic. Accordingly, we consider a class of SLV models with stochastic\ncorrelation where all drivers - the spot, instantaneous variance and their\ncorrelation are modeled by Levy processes. We assume all diffusion components\nto be fully correlated as well as all jump components. A new fully implicit\nsplitting finite-difference scheme is proposed for solving forward PIDE which\nis used when calibrating the model to market prices of the FX options with\ndifferent strikes and maturities. The scheme is unconditionally stable, of\nsecond order of approximation in time and space, and achieves a linear\ncomplexity in each spatial direction. The results of simulation obtained by\nusing this model demonstrate capacity of the presented approach in modeling\nstochastic skew.\n",
"title": "Modeling stochastic skew of FX options using SLV models with stochastic spot/vol correlation and correlated jumps"
}
| null | null | null | null | true | null |
17699
| null |
Default
| null | null |
null |
{
"abstract": " We calculate the amplitude-to-phase (AM-to-PM) noise conversion in a modified\nunitraveling carrier (MUTC) photodetector. We obtained two nulls as measured in\nthe experiments, and we explain their origin. The nulls appear due to the\ntransit time variation when the average photocurrent varies, and the transit\ntime variation is due to the change of electron velocity when the average\nphotocurrent varies. We also show that the AM-to-PM conversion coefficient\ndepends only on the pulse energy and is independent of the pulse duration when\nthe duration is less than 500 fs. When the pulse duration is larger than 500\nfs, the nulls of the AM-to-PM conversion coefficient shift to larger average\nphotocurrents. This shift occurs because the increase in that pulse duration\nleads to a decrease in the peak photocurrent. The AM-to-PM noise conversion\ncoefficient changes as the repetition rate varies. However, the repetition rate\ndoes not change the AM-to-PM conversion coefficient as a function of input\noptical pulse energy. The repetition rate changes the average photocurrent. We\npropose a design that would in theory improve the performance of the device.\n",
"title": "Computational Study of Amplitude-to-Phase Conversion in a Modified Uni-Traveling Carrier (MUTC) Photodetector"
}
| null | null | null | null | true | null |
17700
| null |
Default
| null | null |
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