text
null | inputs
dict | prediction
null | prediction_agent
null | annotation
list | annotation_agent
null | multi_label
bool 1
class | explanation
null | id
stringlengths 1
5
| metadata
null | status
stringclasses 2
values | event_timestamp
null | metrics
null |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
null |
{
"abstract": " As technology become more advanced, those who design, use and are otherwise\naffected by it want to know that it will perform correctly, and understand why\nit does what it does, and how to use it appropriately. In essence they want to\nbe able to trust the systems that are being designed. In this survey we present\nassurances that are the method by which users can understand how to trust this\ntechnology. Trust between humans and autonomy is reviewed, and the implications\nfor the design of assurances are highlighted. A survey of research that has\nbeen performed with respect to assurances is presented, and several key ideas\nare extracted in order to refine the definition of assurances. Several\ndirections for future research are identified and discussed.\n",
"title": "\"I can assure you [$\\ldots$] that it's going to be all right\" -- A definition, case for, and survey of algorithmic assurances in human-autonomy trust relationships"
}
| null | null |
[
"Computer Science",
"Statistics"
] | null | true | null |
9801
| null |
Validated
| null | null |
null |
{
"abstract": " The present work deals with the study of structural, ferroelectric,\ndielectric and electro-caloric effects in lead free ferroelectric\npolycrystalline Ba1-xCaxTi0.95Sn0.05O3 (x= 2, 5 and 10 %) i.e., Ca, Sn co-doped\nBaTiO3 (BTO). Phase purity of the samples is confirmed from X-ray data by using\nRietveld refinement. 119Sn Mössbauer reveals homogenous phase as well as\niso-valent substitution of Sn at Ti site. Enhancements in ferroelectric and\ndielectric properties have been observed. Indirect method which is based on\nMaxwell equation has been used to determine the electro-caloric (EC) effect in\nthe studied ferroelectric ceramics and maximum EC coefficient is observed for\nBa0.95Ca0.05Ti0.95Sn0.05O3.\n",
"title": "Study of Electro-Caloric Effect in Ca and Sn co-Doped BaTiO3 Ceramics"
}
| null | null | null | null | true | null |
9802
| null |
Default
| null | null |
null |
{
"abstract": " In this paper we introduce the notion of a $cdp$-functor to a Waldhausen\ncategory. We show that such functors admit extensions that satisfy the excision\nproperty, to which we associate Euler-Poincaré characteristics that send the\nclass of a proper scheme to the class of its image. As an application, we show\nthat the Yoneda embedding gives rise to a monoidal proper-fibred Waldhausen\ncategory over Noetherian schemes of finite Krull dimensions, with canonical\n$cdp$-functors to its fibres.\n",
"title": "Motivic Measures through Waldhausen K-Theories"
}
| null | null | null | null | true | null |
9803
| null |
Default
| null | null |
null |
{
"abstract": " This monograph aims at providing an introduction to key concepts, algorithms,\nand theoretical results in machine learning. The treatment concentrates on\nprobabilistic models for supervised and unsupervised learning problems. It\nintroduces fundamental concepts and algorithms by building on first principles,\nwhile also exposing the reader to more advanced topics with extensive pointers\nto the literature, within a unified notation and mathematical framework. The\nmaterial is organized according to clearly defined categories, such as\ndiscriminative and generative models, frequentist and Bayesian approaches,\nexact and approximate inference, as well as directed and undirected models.\nThis monograph is meant as an entry point for researchers with a background in\nprobability and linear algebra.\n",
"title": "A Brief Introduction to Machine Learning for Engineers"
}
| null | null | null | null | true | null |
9804
| null |
Default
| null | null |
null |
{
"abstract": " D. Jed Harrison is a full professor at the Department of Chemistry at the\nUniversity of Alberta. Here he describes the development of microfluidic\ntechniques in his lab from the initial demonstration of an integrated\nseparation system for samples in liquids to the recent development of methods\nto fabricate crystalline packed beds with very low defect density.\n",
"title": "The Development of Microfluidic Systems within the Harrison Research Team"
}
| null | null | null | null | true | null |
9805
| null |
Default
| null | null |
null |
{
"abstract": " Liquid helium and spin-1/2 cold-atom Fermi gases both exhibit in their\nsuperfluid phase two distinct types of excitations, gapless phonons and gapped\nrotons or fermionic pair-breaking excitations. In the long wavelength limit,\nrevising and extending Landau and Khalatnikov's theory initially developed for\nhelium [ZhETF 19, 637 (1949)], we obtain universal expressions for three- and\nfour-body couplings among these two types of excitations. We calculate the\ncorresponding phonon damping rates at low temperature and compare them to those\nof a pure phononic origin in high-pressure liquid helium and in strongly\ninteracting Fermi gases, paving the way to experimental observations.\n",
"title": "Landau phonon-roton theory revisited for superfluid helium 4 and Fermi gases"
}
| null | null | null | null | true | null |
9806
| null |
Default
| null | null |
null |
{
"abstract": " We present a probabilistic Las Vegas algorithm for computing the local zeta\nfunction of a genus-$g$ hyperelliptic curve defined over $\\mathbb F_q$ with\nexplicit real multiplication (RM) by an order $\\Z[\\eta]$ in a degree-$g$\ntotally real number field.\nIt is based on the approaches by Schoof and Pila in a more favorable case\nwhere we can split the $\\ell$-torsion into $g$ kernels of endomorphisms, as\nintroduced by Gaudry, Kohel, and Smith in genus 2. To deal with these kernels\nin any genus, we adapt a technique that the author, Gaudry, and Spaenlehauer\nintroduced to model the $\\ell$-torsion by structured polynomial systems.\nApplying this technique to the kernels, the systems we obtain are much smaller\nand so is the complexity of solving them.\nOur main result is that there exists a constant $c>0$ such that, for any\nfixed $g$, this algorithm has expected time and space complexity $O((\\log\nq)^{c})$ as $q$ grows and the characteristic is large enough. We prove that\n$c\\le 8$ and we also conjecture that the result still holds for $c=6$.\n",
"title": "Counting points on hyperelliptic curves with explicit real multiplication in arbitrary genus"
}
| null | null | null | null | true | null |
9807
| null |
Default
| null | null |
null |
{
"abstract": " We prove a sharp Schwarz type inequality for the Weierstrass-Enneper\nrepresentation of the minimal surfaces.\n",
"title": "Minimal surfaces and Schwarz lemma"
}
| null | null |
[
"Mathematics"
] | null | true | null |
9808
| null |
Validated
| null | null |
null |
{
"abstract": " Period estimation is one of the central topics in astronomical time series\nanalysis, where data is often unevenly sampled. Especially challenging are\nstudies of stellar magnetic cycles, as there the periods looked for are of the\norder of the same length than the datasets themselves. The datasets often\ncontain trends, the origin of which is either a real long-term cycle or an\ninstrumental effect, but these effects cannot be reliably separated, while they\ncan lead to erroneous period determinations if not properly handled. In this\nstudy we aim at developing a method that can handle the trends properly, and by\nperforming extensive set of testing, we show that this is the optimal procedure\nwhen contrasted with methods that do not include the trend directly to the\nmodel. The effect of the form of the noise (whether constant or\nheteroscedastic) on the results is also investigated. We introduce a Bayesian\nGeneralised Lomb-Scargle Periodogram with Trend (BGLST), which is a\nprobabilistic linear regression model using Gaussian priors for the\ncoefficients and uniform prior for the frequency parameter. We show, using\nsynthetic data, that when there is no prior information on whether and to what\nextent the true model of the data contains a linear trend, the introduced BGLST\nmethod is preferable to the methods which either detrend the data or leave the\ndata untrended before fitting the periodic model. Whether to use noise with\ndifferent than constant variance in the model depends on the density of the\ndata sampling as well as on the true noise type of the process.\n",
"title": "Estimating activity cycles with probabilistic methods I. Bayesian Generalised Lomb-Scargle Periodogram with Trend"
}
| null | null |
[
"Physics",
"Statistics"
] | null | true | null |
9809
| null |
Validated
| null | null |
null |
{
"abstract": " We propose a new algorithm, Mean Actor-Critic (MAC), for discrete-action\ncontinuous-state reinforcement learning. MAC is a policy gradient algorithm\nthat uses the agent's explicit representation of all action values to estimate\nthe gradient of the policy, rather than using only the actions that were\nactually executed. We prove that this approach reduces variance in the policy\ngradient estimate relative to traditional actor-critic methods. We show\nempirical results on two control domains and on six Atari games, where MAC is\ncompetitive with state-of-the-art policy search algorithms.\n",
"title": "Mean Actor Critic"
}
| null | null | null | null | true | null |
9810
| null |
Default
| null | null |
null |
{
"abstract": " Recent measurements of the Geminga and B0656+14 pulsars by the gamma-ray\ntelescope HAWC (along with earlier measurements by Milagro) indicate that these\nobjects generate significant fluxes of very high-energy electrons. In this\npaper, we use the very high-energy gamma-ray intensity and spectrum of these\npulsars to calculate and constrain their expected contributions to the local\ncosmic-ray positron spectrum. Among models that are capable of reproducing the\nobserved characteristics of the gamma-ray emission, we find that pulsars\ninvariably produce a flux of high-energy positrons that is similar in spectrum\nand magnitude to the positron fraction measured by PAMELA and AMS-02. In light\nof this result, we conclude that it is very likely that pulsars provide the\ndominant contribution to the long perplexing cosmic-ray positron excess.\n",
"title": "HAWC Observations Strongly Favor Pulsar Interpretations of the Cosmic-Ray Positron Excess"
}
| null | null | null | null | true | null |
9811
| null |
Default
| null | null |
null |
{
"abstract": " Deep neural networks require a large amount of labeled training data during\nsupervised learning. However, collecting and labeling so much data might be\ninfeasible in many cases. In this paper, we introduce a source-target selective\njoint fine-tuning scheme for improving the performance of deep learning tasks\nwith insufficient training data. In this scheme, a target learning task with\ninsufficient training data is carried out simultaneously with another source\nlearning task with abundant training data. However, the source learning task\ndoes not use all existing training data. Our core idea is to identify and use a\nsubset of training images from the original source learning task whose\nlow-level characteristics are similar to those from the target learning task,\nand jointly fine-tune shared convolutional layers for both tasks. Specifically,\nwe compute descriptors from linear or nonlinear filter bank responses on\ntraining images from both tasks, and use such descriptors to search for a\ndesired subset of training samples for the source learning task.\nExperiments demonstrate that our selective joint fine-tuning scheme achieves\nstate-of-the-art performance on multiple visual classification tasks with\ninsufficient training data for deep learning. Such tasks include Caltech 256,\nMIT Indoor 67, Oxford Flowers 102 and Stanford Dogs 120. In comparison to\nfine-tuning without a source domain, the proposed method can improve the\nclassification accuracy by 2% - 10% using a single model.\n",
"title": "Borrowing Treasures from the Wealthy: Deep Transfer Learning through Selective Joint Fine-tuning"
}
| null | null | null | null | true | null |
9812
| null |
Default
| null | null |
null |
{
"abstract": " With the development of robotics, there are growing needs for real time\nmotion planning. However, due to obstacles in the environment, the planning\nproblem is highly non-convex, which makes it difficult to achieve real time\ncomputation using existing non-convex optimization algorithms. This paper\nintroduces the convex feasible set algorithm (CFS) which is a fast algorithm\nfor non-convex optimization problems that have convex costs and non-convex\nconstraints. The idea is to find a convex feasible set for the original problem\nand iteratively solve a sequence of subproblems using the convex constraints.\nThe feasibility and the convergence of the proposed algorithm are proved in the\npaper. The application of this method on motion planning for mobile robots is\ndiscussed. The simulations demonstrate the effectiveness of the proposed\nalgorithm.\n",
"title": "The Convex Feasible Set Algorithm for Real Time Optimization in Motion Planning"
}
| null | null | null | null | true | null |
9813
| null |
Default
| null | null |
null |
{
"abstract": " Event cameras are bio-inspired vision sensors that output pixel-level\nbrightness changes instead of standard intensity frames. They offer significant\nadvantages over standard cameras, namely a very high dynamic range, no motion\nblur, and a latency in the order of microseconds. However, due to the\nfundamentally different structure of the sensor's output, new algorithms that\nexploit the high temporal resolution and the asynchronous nature of the sensor\nare required. Recent work has shown that a continuous-time representation of\nthe event camera pose can deal with the high temporal resolution and\nasynchronous nature of this sensor in a principled way. In this paper, we\nleverage such a continuous-time representation to perform visual-inertial\nodometry with an event camera. This representation allows direct integration of\nthe asynchronous events with micro-second accuracy and the inertial\nmeasurements at high frequency. The event camera trajectory is approximated by\na smooth curve in the space of rigid-body motions using cubic splines. This\nformulation significantly reduces the number of variables in trajectory\nestimation problems. We evaluate our method on real data from several scenes\nand compare the results against ground truth from a motion-capture system. We\nshow that our method provides improved accuracy over the result of a\nstate-of-the-art visual odometry method for event cameras. We also show that\nboth the map orientation and scale can be recovered accurately by fusing events\nand inertial data. To the best of our knowledge, this is the first work on\nvisual-inertial fusion with event cameras using a continuous-time framework.\n",
"title": "Continuous-Time Visual-Inertial Odometry for Event Cameras"
}
| null | null |
[
"Computer Science"
] | null | true | null |
9814
| null |
Validated
| null | null |
null |
{
"abstract": " We show an analogy at high curvature between a $f(R) = R + aR^{n - 1} + bR^2$\ntheory and the $\\alpha$-Attractors. We calculate the expressions of the\nparameters $a$, $b$ and $n$ as functions of $\\alpha$ and the predictions of the\nmodel $f(R) = R + aR^{n - 1} + bR^2$ on the scalar spectral index $n_{\\rm s}$\nand the tensor-to-scalar ratio $r$. We find that the power law correction $R^{n\n- 1}$ allows for a production of gravitational waves enhanced with respect to\nthe one in the Starobinsky model, while maintaining a viable prediction on\n$n_{\\rm s}$. We numerically reconstruct the full $\\alpha$-Attractors class of\nmodels testing the goodness of our high-energy approximation $f(R) = R + aR^{n\n- 1} + bR^2$. Moreover, we also investigate the case of a single power law\n$f(R) = \\gamma R^{2 - \\delta}$ theory, with $\\gamma$ and $\\delta$ free\nparameters. We calculate analytically the predictions of this model on the\nscalar spectral index $n_{\\rm s}$ and the tensor-to-scalar ratio $r$ and the\nvalues of $\\delta$ which are allowed from the current observational results. We\nfind that $-0.015 < \\delta < 0.016$, confirming once again the excellent\nagreement between the Starobinsky model and observation.\n",
"title": "Reconstructing a $f(R)$ theory from the $α$-Attractors"
}
| null | null | null | null | true | null |
9815
| null |
Default
| null | null |
null |
{
"abstract": " We introduce and solve a new type of quadratic backward stochastic\ndifferential equation systems defined in an infinite time horizon, called\n\\emph{ergodic BSDE systems}. Such systems arise naturally as candidate\nsolutions to characterize forward performance processes and their associated\noptimal trading strategies in a regime switching market. In addition, we\ndevelop a connection between the solution of the ergodic BSDE system and the\nlong-term growth rate of classical utility maximization problems, and use the\nergodic BSDE system to study the large time behavior of PDE systems with\nquadratic growth Hamiltonians.\n",
"title": "Systems of ergodic BSDE arising in regime switching forward performance processes"
}
| null | null |
[
"Quantitative Finance"
] | null | true | null |
9816
| null |
Validated
| null | null |
null |
{
"abstract": " Due to recent advances in technology, the recording and analysis of video\ndata has become an increasingly common component of athlete training\nprogrammes. Today it is incredibly easy and affordable to set up a fixed camera\nand record athletes in a wide range of sports, such as diving, gymnastics,\ngolf, tennis, etc. However, the manual analysis of the obtained footage is a\ntime-consuming task which involves isolating actions of interest and\ncategorizing them using domain-specific knowledge. In order to automate this\nkind of task, three challenging sub-problems are often encountered: 1)\ntemporally cropping events/actions of interest from continuous video; 2)\ntracking the object of interest; and 3) classifying the events/actions of\ninterest.\nMost previous work has focused on solving just one of the above sub-problems\nin isolation. In contrast, this paper provides a complete solution to the\noverall action monitoring task in the context of a challenging real-world\nexemplar. Specifically, we address the problem of diving classification. This\nis a challenging problem since the person (diver) of interest typically\noccupies fewer than 1% of the pixels in each frame. The model is required to\nlearn the temporal boundaries of a dive, even though other divers and\nbystanders may be in view. Finally, the model must be sensitive to subtle\nchanges in body pose over a large number of frames to determine the\nclassification code. We provide effective solutions to each of the sub-problems\nwhich combine to provide a highly functional solution to the task as a whole.\nThe techniques proposed can be easily generalized to video footage recorded\nfrom other sports.\n",
"title": "Extraction and Classification of Diving Clips from Continuous Video Footage"
}
| null | null | null | null | true | null |
9817
| null |
Default
| null | null |
null |
{
"abstract": " We give a parametrization of the simple Bernstein components of inner forms\nof a general linear group over a local field by invariants constructed from\ntype theory, and explicitly describe its behaviour under the Jacquet-Langlands\ncorrespondence. Along the way, we prove a conjecture of Broussous, Sécherre\nand Stevens on preservation of endo-classes.\n",
"title": "The inertial Jacquet-Langlands correspondence"
}
| null | null | null | null | true | null |
9818
| null |
Default
| null | null |
null |
{
"abstract": " As an injury heals, an embryo develops, or a carcinoma spreads, epithelial\ncells systematically change their shape. In each of these processes cell shape\nis studied extensively, whereas variation of shape from cell-to-cell is\ndismissed most often as biological noise. But where do cell shape and variation\nof cell shape come from? Here we report that cell shape and shape variation are\nmutually constrained through a relationship that is purely geometrical. That\nrelationship is shown to govern maturation of the pseudostratified bronchial\nepithelial layer cultured from both non-asthmatic and asthmatic donors as well\nas formation of the ventral furrow in the epithelial monolayer of the\nDrosophila embryo in vivo. Across these and other vastly different epithelial\nsystems, cell shape variation collapses to a family of distributions that is\ncommon to all and potentially universal. That distribution, in turn, is\naccounted for quantitatively by a mechanistic theory of cell-cell interaction\nshowing that cell shape becomes progressively less elongated and less variable\nas the layer becomes progressively more jammed. These findings thus uncover a\nconnection between jamming and geometry that is generic -spanning jammed living\nand inert systems alike- and demonstrate that proximity of the cell layer to\nthe jammed state is the principal determinant of the most primitive features of\nepithelial cell shape and shape variation.\n",
"title": "Universal geometric constraints during epithelial jamming"
}
| null | null | null | null | true | null |
9819
| null |
Default
| null | null |
null |
{
"abstract": " Among Sequential Monte Carlo (SMC) methods,Sampling Importance Resampling\n(SIR) algorithms are based on Importance Sampling (IS) and on some\nresampling-based)rejuvenation algorithm which aims at fighting against weight\ndegeneracy. However %whichever the resampling technique used this mechanism\ntends to be insufficient when applied to informative or high-dimensional\nmodels. In this paper we revisit the rejuvenation mechanism and propose a class\nof parameterized SIR-based solutions which enable to adjust the tradeoff\nbetween computational cost and statistical performances.\n",
"title": "Semi-independent resampling for particle filtering"
}
| null | null | null | null | true | null |
9820
| null |
Default
| null | null |
null |
{
"abstract": " How can we approach the truth in a society? It may depend on various factors.\nIn this paper, using a well-established truth seeking model, we show that the\npersistent free information flow will bring us to the truth. Here the free\ninformation flow is modeled as the environmental random noise that could alter\none's cognition. Without the random noise, the model predicts that the truth\ncan only be captured by the truth seekers who own active perceptive ability of\nthe truth and their believers, while the other individuals may stick to\nfalsehood. But under the influence of the random noise, we strictly prove that\neven there is only one truth seeker in the group, all individuals will finally\napproach the truth.\n",
"title": "Free Information Flow Benefits Truth Seeking"
}
| null | null | null | null | true | null |
9821
| null |
Default
| null | null |
null |
{
"abstract": " Increasing evidence has shown that theory-based health behavior change\ninterventions are more effective than non-theory-based ones. However, only a\nfew segments of relevant studies were theory-based, especially the studies\nconducted by non-psychology researchers. On the other hand, many mobile health\ninterventions, even those based on the behavioral theories, may still fail in\nthe absence of a user-centered design process. The gap between behavioral\ntheories and user-centered design increases the difficulty of designing and\nimplementing mobile health interventions. To bridge this gap, we propose a\nholistic approach to designing theory-based mobile health interventions built\non the existing theories and frameworks of three categories: (1) behavioral\ntheories (e.g., the Social Cognitive Theory, the Theory of Planned Behavior,\nand the Health Action Process Approach), (2) the technological models and\nframeworks (e.g., the Behavior Change Techniques, the Persuasive System Design\nand Behavior Change Support System, and the Just-in-Time Adaptive\nInterventions), and (3) the user-centered systematic approaches (e.g., the\nCeHRes Roadmap, the Wendel's Approach, and the IDEAS Model). This holistic\napproach provides researchers a lens to see the whole picture for developing\nmobile health interventions.\n",
"title": "Towards a Holistic Approach to Designing Theory-based Mobile Health Interventions"
}
| null | null |
[
"Computer Science"
] | null | true | null |
9822
| null |
Validated
| null | null |
null |
{
"abstract": " In a recent publication [Appl. Opt. 55, 2418 (2016)], a method for\ntwo-dimensional phase unwrapping based on the transport of intensity equation\n(TIE) was studied. We wish to show that this approach is associated with the\nstandard least squares phase unwrapping algorithm, but with additional\nnumerical errors.\n",
"title": "Connections between transport of intensity equation and two-dimensional phase unwrapping"
}
| null | null | null | null | true | null |
9823
| null |
Default
| null | null |
null |
{
"abstract": " We derive new approximations for the Value at Risk and the Expected Shortfall\nat high levels of loss distributions with positive skewness and excess\nkurtosis, and we describe their precisions for notable ones such as for\nexponential, Pareto type I, lognormal and compound (Poisson) distributions. Our\napproximations are motivated by extensions of the so-called Normal Power\nApproximation, used for approximating the cumulative distribution function of a\nrandom variable, incorporating not only the skewness but the kurtosis of the\nrandom variable in question as well. We show the performance of our\napproximations in numerical examples and we also give comparisons with some\nknown ones in the literature.\n",
"title": "On approximations of Value at Risk and Expected Shortfall involving kurtosis"
}
| null | null | null | null | true | null |
9824
| null |
Default
| null | null |
null |
{
"abstract": " Computational methods that predict differential gene expression from histone\nmodification signals are highly desirable for understanding how histone\nmodifications control the functional heterogeneity of cells through influencing\ndifferential gene regulation. Recent studies either failed to capture\ncombinatorial effects on differential prediction or primarily only focused on\ncell type-specific analysis. In this paper, we develop a novel attention-based\ndeep learning architecture, DeepDiff, that provides a unified and end-to-end\nsolution to model and to interpret how dependencies among histone modifications\ncontrol the differential patterns of gene regulation. DeepDiff uses a hierarchy\nof multiple Long short-term memory (LSTM) modules to encode the spatial\nstructure of input signals and to model how various histone modifications\ncooperate automatically. We introduce and train two levels of attention jointly\nwith the target prediction, enabling DeepDiff to attend differentially to\nrelevant modifications and to locate important genome positions for each\nmodification. Additionally, DeepDiff introduces a novel deep-learning based\nmulti-task formulation to use the cell-type-specific gene expression\npredictions as auxiliary tasks, encouraging richer feature embeddings in our\nprimary task of differential expression prediction. Using data from Roadmap\nEpigenomics Project (REMC) for ten different pairs of cell types, we show that\nDeepDiff significantly outperforms the state-of-the-art baselines for\ndifferential gene expression prediction. The learned attention weights are\nvalidated by observations from previous studies about how epigenetic mechanisms\nconnect to differential gene expression. Codes and results are available at\n\\url{deepchrome.org}\n",
"title": "DeepDiff: Deep-learning for predicting Differential gene expression from histone modifications"
}
| null | null | null | null | true | null |
9825
| null |
Default
| null | null |
null |
{
"abstract": " Modern datasets and models are notoriously difficult to explore and analyze\ndue to their inherent high dimensionality and massive numbers of samples.\nExisting visualization methods which employ dimensionality reduction to two or\nthree dimensions are often inefficient and/or ineffective for these datasets.\nThis paper introduces t-SNE-CUDA, a GPU-accelerated implementation of\nt-distributed Symmetric Neighbor Embedding (t-SNE) for visualizing datasets and\nmodels. t-SNE-CUDA significantly outperforms current implementations with\n50-700x speedups on the CIFAR-10 and MNIST datasets. These speedups enable, for\nthe first time, visualization of the neural network activations on the entire\nImageNet dataset - a feat that was previously computationally intractable. We\nalso demonstrate visualization performance in the NLP domain by visualizing the\nGloVe embedding vectors. From these visualizations, we can draw interesting\nconclusions about using the L2 metric in these embedding spaces. t-SNE-CUDA is\npublicly available atthis https URL\n",
"title": "t-SNE-CUDA: GPU-Accelerated t-SNE and its Applications to Modern Data"
}
| null | null | null | null | true | null |
9826
| null |
Default
| null | null |
null |
{
"abstract": " Matching members in the Coma cluster catalogue of ultra-diffuse galaxies\n(UDGs, Yagi et al. 2016) from SUBARU imaging with a very deep radio continuum\nsurvey source catalogue of the cluster (Miller et al. 2009) using the Karl G.\nJansky Very Large Array (VLA) within a rectangular region of ~ 1.19 square\ndegrees centred on the cluster core reveals matches consistent with random. An\noverlapping set of 470 UDGs and 696 VLA radio sources in this rectangular area\nfinds 33 matches within a separation of 25 arcsec; dividing the sample into\nbins with separations bounded by 5 arcsec, 10 arcsec, 20 arcsec and 25 arcsec\nfinds 1, 4, 17 and 11 matches. An analytical model estimate, based on the\nPoisson probability distribution, of the number of randomly expected matches\nwithin these same separation bounds is 1.7, 4.9, 19.4 and 14.2, each\nrespectively consistent with the 95 percent Poisson confidence intervals of the\nobserved values. Dividing the data into five clustercentric annuli of 0.1\ndegree, and into the four separation bins, finds the same result. This random\nmatch of UDGs with VLA sources implies that UDGs are not radio galaxies by the\nstandard definition. Those VLA sources having integrated flux > 1 mJy at 1.4\nGHz in Miller et al. (2009) without SDSS galaxy matches are consistent with the\nknown surface density of background radio sources. We briefly explore the\npossibility that some unresolved VLA sources near UDGs could be young, compact,\nbright, supernova remnants of type Ia events, possibly in the intracluster\nvolume.\n",
"title": "Coma Cluster Ultra-Diffuse Galaxies Are Not Standard Radio Galaxies"
}
| null | null |
[
"Physics"
] | null | true | null |
9827
| null |
Validated
| null | null |
null |
{
"abstract": " In this work we discuss the related challenges and describe an approach\ntowards the fusion of state-of-the-art technologies from the Spoken Dialogue\nSystems (SDS) and the Semantic Web and Information Retrieval domains. We\nenvision a dialogue system named LD-SDS that will support advanced, expressive,\nand engaging user requests, over multiple, complex, rich, and open-domain data\nsources that will leverage the wealth of the available Linked Data.\nSpecifically, we focus on: a) improving the identification, disambiguation and\nlinking of entities occurring in data sources and user input; b) offering\nadvanced query services for exploiting the semantics of the data, with\nreasoning and exploratory capabilities; and c) expanding the typical\ninformation seeking dialogue model (slot filling) to better reflect real-world\nconversational search scenarios.\n",
"title": "LD-SDS: Towards an Expressive Spoken Dialogue System based on Linked-Data"
}
| null | null | null | null | true | null |
9828
| null |
Default
| null | null |
null |
{
"abstract": " Recently, inference about high-dimensional integrated covariance matrices\n(ICVs) based on noisy high-frequency data has emerged as a challenging problem.\nIn the literature, a pre-averaging estimator (PA-RCov) is proposed to deal with\nthe microstructure noise. Using the large-dimensional random matrix theory, it\nhas been established that the eigenvalue distribution of the PA-RCov matrix is\nintimately linked to that of the ICV through the Marcenko-Pastur equation.\nConsequently, the spectrum of the ICV can be inferred from that of the PA-RCov.\nHowever, extensive data analyses demonstrate that the spectrum of the PA-RCov\nis spiked, that is, a few large eigenvalues (spikes) stay away from the others\nwhich form a rather continuous distribution with a density function (bulk).\nTherefore, any inference on the ICVs must take into account this spiked\nstructure. As a methodological contribution, we propose a spiked model for the\nICVs where spikes can be inferred from those of the available PA-RCov matrices.\nThe consistency of the inference procedure is established and is checked by\nextensive simulation studies. In addition, we apply our method to the real data\nfrom the US and Hong Kong markets. It is found that our model clearly\noutperforms the existing one in predicting the existence of spikes and in\nmimicking the empirical PA-RCov matrices.\n",
"title": "On a spiked model for large volatility matrix estimation from noisy high-frequency data"
}
| null | null | null | null | true | null |
9829
| null |
Default
| null | null |
null |
{
"abstract": " While online communities have become increasingly important over the years,\nthe moderation of user-generated content is still performed mostly manually.\nAutomating this task is an important step in reducing the financial cost\nassociated with moderation, but the majority of automated approaches strictly\nbased on message content are highly vulnerable to intentional obfuscation. In\nthis paper, we discuss methods for extracting conversational networks based on\nraw multi-participant chat logs, and we study the contribution of graph\nfeatures to a classification system that aims to determine if a given message\nis abusive. The conversational graph-based system yields unexpectedly high\nperformance , with results comparable to those previously obtained with a\ncontent-based approach.\n",
"title": "Graph-based Features for Automatic Online Abuse Detection"
}
| null | null | null | null | true | null |
9830
| null |
Default
| null | null |
null |
{
"abstract": " We show that all known classical adversary lower bounds on randomized query\ncomplexity are equivalent for total functions, and are equal to the fractional\nblock sensitivity $\\text{fbs}(f)$. That includes the Kolmogorov complexity\nbound of Laplante and Magniez and the earlier relational adversary bound of\nAaronson. This equivalence also implies that for total functions, the\nrelational adversary is equivalent to a simpler lower bound, which we call\nrank-1 relational adversary. For partial functions, we show unbounded\nseparations between $\\text{fbs}(f)$ and other adversary bounds, as well as\nbetween the adversary bounds themselves.\nWe also show that, for partial functions, fractional block sensitivity cannot\ngive lower bounds larger than $\\sqrt{n \\cdot \\text{bs}(f)}$, where $n$ is the\nnumber of variables and $\\text{bs}(f)$ is the block sensitivity. Then we\nexhibit a partial function $f$ that matches this upper bound, $\\text{fbs}(f) =\n\\Omega(\\sqrt{n \\cdot \\text{bs}(f)})$.\n",
"title": "All Classical Adversary Methods are Equivalent for Total Functions"
}
| null | null |
[
"Computer Science"
] | null | true | null |
9831
| null |
Validated
| null | null |
null |
{
"abstract": " The short-spacing problem describes the inherent inability of\nradio-interferometric arrays to measure the integrated flux and structure of\ndiffuse emission associated with extended sources. New interferometric arrays,\nsuch as SKA, require solutions to efficiently combine interferometer and\nsingle-dish data.\nWe present a new and open source approach for merging single-dish and cleaned\ninterferometric data sets requiring a minimum of data manipulation while\noffering a rigid flux determination and full high angular resolution. Our\napproach combines single-dish and cleaned interferometric data in the image\ndomain. This approach is tested for both Galactic and extragalactic HI data\nsets. Furthermore, a quantitative comparison of our results to commonly used\nmethods is provided. Additionally, for the interferometric data sets of NGC4214\nand NGC5055, we study the impact of different imaging parameters as well as\ntheir influence on the combination for NGC4214.\nThe approach does not require the raw data (visibilities) or any additional\nspecial information such as antenna patterns. This is advantageous especially\nin the light of upcoming radio surveys with heterogeneous antenna designs.\n",
"title": "A new approach for short-spacing correction of radio interferometric data sets"
}
| null | null | null | null | true | null |
9832
| null |
Default
| null | null |
null |
{
"abstract": " Estimation of tail quantities, such as expected shortfall or Value at Risk,\nis a difficult problem. We show how the theory of nonlinear expectations, in\nparticular the Data-robust expectation introduced in [5], can assist in the\nquantification of statistical uncertainty for these problems. However, when we\nare in a heavy-tailed context (in particular when our data are described by a\nPareto distribution, as is common in much of extreme value theory), the theory\nof [5] is insufficient, and requires an additional regularization step which we\nintroduce. By asking whether this regularization is possible, we obtain a\nqualitative requirement for reliable estimation of tail quantities and risk\nmeasures, in a Pareto setting.\n",
"title": "Data and uncertainty in extreme risks - a nonlinear expectations approach"
}
| null | null | null | null | true | null |
9833
| null |
Default
| null | null |
null |
{
"abstract": " We derive flow equations for cold atomic gases with one macroscopically\npopulated energy level. The generator is chosen such that the ground state\ndecouples from all other states in the system as the renormalization group flow\nprogresses. We propose a self-consistent truncation scheme for the flow\nequations at the level of three-body operators and show how they can be used to\ncalculate the ground state energy of a general $N$-body system. Moreover, we\nprovide a general method to estimate the truncation error in the calculated\nenergies. Finally, we test our scheme by benchmarking to the exactly solvable\nLieb-Liniger model and find good agreement for weak and moderate interaction\nstrengths.\n",
"title": "Flow equations for cold Bose gases"
}
| null | null | null | null | true | null |
9834
| null |
Default
| null | null |
null |
{
"abstract": " A dynamic self-organized morphology is the hallmark of network-shaped\norganisms like slime moulds and fungi. Organisms continuously re-organize their\nflexible, undifferentiated body plans to forage for food. Among these organisms\nthe slime mould Physarum polycephalum has emerged as a model to investigate how\norganism can self-organize their extensive networks and act as a coordinated\nwhole. Cytoplasmic fluid flows flowing through the tubular networks have been\nidentified as key driver of morphological dynamics. Inquiring how fluid flows\ncan shape living matter from small to large scales opens up many new avenues\nfor research.\n",
"title": "Fluid flows shaping organism morphology"
}
| null | null | null | null | true | null |
9835
| null |
Default
| null | null |
null |
{
"abstract": " In this note we investigate the existence of frames of exponentials for\n$L^2(\\Omega)$ in the setting of LCA groups. Our main result shows that\nsub-multitiling properties of $\\Omega \\subset \\widehat{G}$ with respect to a\nuniform lattice $\\Gamma$ of $\\widehat{G}$ guarantee the existence of a frame of\nexponentials with frequencies in a finite number of translates of the\nannihilator of $\\Gamma$. We also prove the converse of this result and provide\nconditions for the existence of these frames. These conditions extend recent\nresults on Riesz bases of exponentials and multitilings to frames.\n",
"title": "Frames of exponentials and sub-multitiles in LCA groups"
}
| null | null | null | null | true | null |
9836
| null |
Default
| null | null |
null |
{
"abstract": " With the growth of interest in network data across fields, the Exponential\nRandom Graph Model (ERGM) has emerged as the leading approach to the\nstatistical analysis of network data. ERGM parameter estimation requires the\napproximation of an intractable normalizing constant. Simulation methods\nrepresent the state-of-the-art approach to approximating the normalizing\nconstant, leading to estimation by Monte Carlo maximum likelihood (MCMLE).\nMCMLE is accurate when a large sample of networks is used to approximate the\nnormalizing constant. However, MCMLE is computationally expensive, and may be\nprohibitively so if the size of the network is on the order of 1,000 nodes\n(i.e., one million potential ties) or greater. When the network is large, one\noption is maximum pseudolikelihood estimation (MPLE). The standard MPLE is\nsimple and fast, but generally underestimates standard errors. We show that a\nresampling method---the parametric bootstrap---results in accurate coverage\nprobabilities for confidence intervals. We find that bootstrapped MPLE can be\nrun in 1/5th the time of MCMLE. We study the relative performance of MCMLE and\nMPLE with simulation studies, and illustrate the two different approaches by\napplying them to a network of bills introduced in the United State Senate.\n",
"title": "Exponential Random Graph Models with Big Networks: Maximum Pseudolikelihood Estimation and the Parametric Bootstrap"
}
| null | null | null | null | true | null |
9837
| null |
Default
| null | null |
null |
{
"abstract": " In this paper we present our study on the critical behavior of a stochastic\nanisotropic Bak-Sneppen (saBS) model, in which a parameter $\\alpha$ is\nintroduced to describe the interaction strength among nearest species. We\nestimate the threshold fitness $f_c$ and the critical exponent $\\tau_r$ by\nnumerically integrating a master equation for the distribution of avalanche\nspatial sizes. Other critical exponents are then evaluated from previously\nknown scaling relations. The numerical results are in good agreement with the\ncounterparts yielded by the Monte Carlo simulations. Our results indicate that\nall saBS models with nonzero interaction strength exhibit self-organized\ncriticality, and fall into the same universality class, by sharing the\nuniversal critical exponents.\n",
"title": "Critical behavior of a stochastic anisotropic Bak-Sneppen model"
}
| null | null |
[
"Physics"
] | null | true | null |
9838
| null |
Validated
| null | null |
null |
{
"abstract": " The study of covariances (or positive definite functions) on the sphere (the\nEarth, in our motivation) goes back to Bochner and Schoenberg (1940--42) and to\nthe first author (1969, 1973), among others. Extending to the geotemporal case\n(sphere cross line, for position and time) was for a long time an obstacle to\ngeostatistical modelling. The characterisation question here was raised by the\nauthors and Mijatović in 2016, and answered by Berg and Porcu in 2017.\nExtensions to multiple products (of spheres and lines) follows similarly\n(Guella, Menegatto and Peron, 2016). We survey results of this type, and\nrelated applications e.g. in numerical weather prediction.\n",
"title": "Probability, Statistics and Planet Earth, I: Geotemporal covariances"
}
| null | null | null | null | true | null |
9839
| null |
Default
| null | null |
null |
{
"abstract": " Many cloud applications rely on fast and non-relational storage to aid in the\nprocessing of large amounts of data. Managed runtimes are now widely used to\nsupport the execution of several storage solutions of the NoSQL movement,\nparticularly when dealing with big data key-value store-driven applications.\nThe benefits of these runtimes can however be limited by modern parallel\nthroughput-oriented GC algorithms, where related objects have the potential to\nbe dispersed in memory, either in the same or different generations. In the\nlong run this causes more page faults and degradation of locality on\nsystem-level memory caches.\nWe propose, Gang-CG, an extension to modern heap layouts and to a parallel GC\nalgorithm to promote locality between groups of related objects. This is done\nwithout extensive profiling of the applications and in a way that is\ntransparent to the programmer, without the need to use specialized data\nstructures. The heap layout and algorithmic extensions were implemented over\nthe Parallel Scavenge garbage collector of the HotSpot JVM\\@.\nUsing microbenchmarks that capture the architecture of several key-value\nstores databases, we show negligible overhead in frequent operations such as\nthe allocation of new objects and improvements to the access speed of data,\nsupported by lower misses in system-level memory caches. Overall, we show a 6\\%\nimprovement in the average time of read and update operations and an average\ndecrease of 12.4\\% in page faults.\n",
"title": "Gang-GC: Locality-aware Parallel Data Placement Optimizations for Key-Value Storages"
}
| null | null | null | null | true | null |
9840
| null |
Default
| null | null |
null |
{
"abstract": " A long standing problem in the area of error correcting codes asks whether\nthere exist good cyclic codes. Most of the known results point in the direction\nof a negative answer.\nThe uncertainty principle is a classical result of harmonic analysis\nasserting that given a non-zero function $f$ on some abelian group, either $f$\nor its Fourier transform $\\hat{f}$ has large support.\nIn this note, we observe a connection between these two subjects. We point\nout that even a weak version of the uncertainty principle for fields of\npositive characteristic would imply that good cyclic codes do exist. We also\nprovide some heuristic arguments supporting that this is indeed the case.\n",
"title": "Good cyclic codes and the uncertainty principle"
}
| null | null | null | null | true | null |
9841
| null |
Default
| null | null |
null |
{
"abstract": " Drones, also known as mini-unmanned aerial vehicles, have attracted\nincreasing attention due to their boundless applications in communications,\nphotography, agriculture, surveillance and numerous public services. However,\nthe deployment of amateur drones poses various safety, security and privacy\nthreats. To cope with these challenges, amateur drone surveillance becomes a\nvery important but largely unexplored topic. In this article, we firstly\npresent a brief survey to show the state-of-the-art studies on amateur drone\nsurveillance. Then, we propose a vision, named Dragnet, by tailoring the recent\nemerging cognitive internet of things framework for amateur drone surveillance.\nNext, we discuss the key enabling techniques for Dragnet in details,\naccompanied with the technical challenges and open issues. Furthermore, we\nprovide an exemplary case study on the detection and classification of\nauthorized and unauthorized amateur drones, where, for example, an important\nevent is being held and only authorized drones are allowed to fly over.\n",
"title": "An Amateur Drone Surveillance System Based on Cognitive Internet of Things"
}
| null | null | null | null | true | null |
9842
| null |
Default
| null | null |
null |
{
"abstract": " We investigate the weak excitations of a system made up of two condensates\ntrapped in a Bose-Hubbard ring and coupled by an interspecies repulsive\ninteraction. Our approach, based on the Bogoliubov approximation scheme, shows\nthat one can reduce the problem Hamiltonian to the sum of sub-Hamiltonians\n$\\hat{H}_k$, each one associated to momentum modes $\\pm k$. Each $\\hat{H}_k$ is\nthen recognized to be an element of a dynamical algebra. This uncommon and\nremarkable property allows us to present a straightforward diagonalization\nscheme, to find constants of motion, to highlight the significant microscopic\nprocesses, and to compute their time evolution. The proposed solution scheme is\napplied to a simple but still very interesting closed circuit, the trimer. The\ndynamics of low-energy excitations, corresponding to weakly-populated vortices,\nis investigated considering different choices of the initial conditions, and\nthe angular-momentum transfer between the two condensates is evidenced.\nFinally, the condition for which the spectral collapse and dynamical\ninstability are observed is derived analytically.\n",
"title": "Two-species boson mixture on a ring: A group theoretic approach to the quantum dynamics of low-energy excitations"
}
| null | null | null | null | true | null |
9843
| null |
Default
| null | null |
null |
{
"abstract": " We find plane models for all $X_0(N)$, $N\\geq 2$. We observe a map from the\nmodular curve $X_0(N)$ to the projective plane constructed using modular forms\nof weight $12$ for the group $\\Gamma_0(N)$; the Ramanujan function $\\Delta$,\n$\\Delta(N\\cdot)$ and the third power of Eisestein series of weight $4$,\n$E_4^3$, and prove that this map is birational equivalence for every $N\\geq 2$.\nThe equation of the model is the minimal polynomial of $\\Delta(N\\cdot)/\\Delta$\nover $\\mathbb{C}(j)$.\n",
"title": "On a simple model of X_0(N)"
}
| null | null | null | null | true | null |
9844
| null |
Default
| null | null |
null |
{
"abstract": " Neural networks have shown great potential in many applications like speech\nrecognition, drug discovery, image classification, and object detection. Neural\nnetwork models are inspired by biological neural networks, but they are\noptimized to perform machine learning tasks on digital computers. The proposed\nwork explores the possibilities of using living neural networks in vitro as\nbasic computational elements for machine learning applications. A new\nsupervised STDP-based learning algorithm is proposed in this work, which\nconsiders neuron engineering constrains. A 74.7% accuracy is achieved on the\nMNIST benchmark for handwritten digit recognition.\n",
"title": "A Supervised STDP-based Training Algorithm for Living Neural Networks"
}
| null | null | null | null | true | null |
9845
| null |
Default
| null | null |
null |
{
"abstract": " The transient response of power grids to external disturbances influences\ntheir stable operation. This paper studies the effect of topology in linear\ntime-invariant dynamics of different power grids. For a variety of objective\nfunctions, a unified framework based on $H_2$ norm is presented to analyze the\nrobustness to ambient fluctuations. Such objectives include loss reduction,\nweighted consensus of phase angle deviations, oscillations in nodal frequency,\nand other graphical metrics. The framework is then used to study the problem of\noptimal topology design for robust control goals of different grids. For radial\ngrids, the problem is shown as equivalent to the hard \"optimum communication\nspanning tree\" problem in graph theory and a combinatorial topology\nconstruction is presented with bounded approximation gap. Extended to loopy\n(meshed) grids, a greedy topology design algorithm is discussed. The\nperformance of the topology design algorithms under multiple control objectives\nare presented on both loopy and radial test grids. Overall, this paper analyzes\ntopology design algorithms on a broad class of control problems in power grid\nby exploring their combinatorial and graphical properties.\n",
"title": "Optimal Topology Design for Disturbance Minimization in Power Grids"
}
| null | null | null | null | true | null |
9846
| null |
Default
| null | null |
null |
{
"abstract": " We present a family of mutually orthogonal polynomials on the unit ball with\nrespect to an inner product which includes a mass uniformly distributed on the\nsphere. First, connection formulas relating these multivariate orthogonal\npolynomials and the classical ball polynomials are obtained. Then, using the\nrepresentation formula for these polynomials in terms of spherical harmonics\nanalytic properties will be deduced. Finally, we analyze the asymptotic\nbehaviour of the Christoffel functions.\n",
"title": "Asymptotic behaviour of the Christoffel functions on the Unit Ball in the presence of a Mass on the Sphere"
}
| null | null | null | null | true | null |
9847
| null |
Default
| null | null |
null |
{
"abstract": " Automatic differentiation (AD) is an essential primitive for machine learning\nprogramming systems. Tangent is a new library that performs AD using source\ncode transformation (SCT) in Python. It takes numeric functions written in a\nsyntactic subset of Python and NumPy as input, and generates new Python\nfunctions which calculate a derivative. This approach to automatic\ndifferentiation is different from existing packages popular in machine\nlearning, such as TensorFlow and Autograd. Advantages are that Tangent\ngenerates gradient code in Python which is readable by the user, easy to\nunderstand and debug, and has no runtime overhead. Tangent also introduces\nabstractions for easily injecting logic into the generated gradient code,\nfurther improving usability.\n",
"title": "Tangent: Automatic Differentiation Using Source Code Transformation in Python"
}
| null | null | null | null | true | null |
9848
| null |
Default
| null | null |
null |
{
"abstract": " We describe here a procedure to combine measurements in the 393.37 nm Ca II K\nspectral line taken at different observatories. Measurements from the National\nSolar Observatory (NSO) Integrated Sunlight Spectrometer (ISS) on the Synoptic\nOptical Long-term Investigations of the Sun (SOLIS) telescope, the NSO/Sac Peak\nCa II K-Line Monitoring Program, and Ca II K filtergrams from Kodaikanal Solar\nObservatory (KKL) are merged together to create a pair of composites of the Ca\nII K 1-A emission index. These composites are publicly available from the SOLIS\nwebsite at this http URL.\n",
"title": "Ca II K 1-A Emission Index Composites"
}
| null | null |
[
"Physics"
] | null | true | null |
9849
| null |
Validated
| null | null |
null |
{
"abstract": " Microwave cavities for a Sikivie-type axion search are subject to several\nconstraints. In the fabrication and operation of such cavities, often used at\nfrequencies where the resonator is highly overmoded, it is important to be able\nto reliably identify several properties of the cavity. Those include\nidentifying the symmetry of the mode of interest, confirming its form factor,\nand determining the frequency ranges where mode crossings with intruder levels\ncause unacceptable admixture, thus leading to the loss of purity of the mode of\ninterest. A simple and powerful diagnostic for mapping out the electric field\nof a cavity is the bead perturbation technique. While a standard tool in\naccelerator physics, we have, for the first time, applied this technique to\ncavities used in the axion search. We report initial results from an extensive\nstudy for the initial cavity used in the HAYSTAC experiment. Two effects have\nbeen investigated: the role of rod misalignment in mode localization, and\nmode-mixing at avoided crossings of TM/TE modes. Future work will extend these\nresults by incorporating precision metrology and high-fidelity simulations.\n",
"title": "Application of the Bead Perturbation Technique to a Study of a Tunable 5 GHz Annular Cavity"
}
| null | null | null | null | true | null |
9850
| null |
Default
| null | null |
null |
{
"abstract": " We determine all connected homogeneous Kobayashi-hyperbolic manifolds of\ndimension $n\\ge 2$ whose holomorphic automorphism group has dimension $n^2-2$.\nThis result complements an existing classification for automorphism group\ndimension $n^2-1$ and greater obtained without the homogeneity assumption.\n",
"title": "Homogeneous Kobayashi-hyperbolic manifolds with high-dimensional group of holomorphic automorphisms"
}
| null | null |
[
"Mathematics"
] | null | true | null |
9851
| null |
Validated
| null | null |
null |
{
"abstract": " In this paper we first establish new explicit estimates for Chebyshev's\n$\\vartheta$-function. Applying these new estimates, we derive new upper and\nlower bounds for some functions defined over the prime numbers, for instance\nthe prime counting function $\\pi(x)$, which improve the currently best ones.\nFurthermore, we use the obtained estimates for the prime counting function to\ngive two new results concerning the existence of prime numbers in short\nintervals.\n",
"title": "New estimates for some functions defined over primes"
}
| null | null | null | null | true | null |
9852
| null |
Default
| null | null |
null |
{
"abstract": " While there has been an explosion in the number of experimentally determined,\natomically detailed structures of proteins, how to represent these structures\nin a machine learning context remains an open research question. In this work\nwe demonstrate that representations learned from raw atomic coordinates can\noutperform hand-engineered structural features while displaying a much higher\ndegree of transferrability. To do so, we focus on a central problem in biology:\npredicting how proteins interact with one another--that is, which surfaces of\none protein bind to which surfaces of another protein. We present Siamese\nAtomic Surfacelet Network (SASNet), the first end-to-end learning method for\nprotein interface prediction. Despite using only spatial coordinates and\nidentities of atoms as inputs, SASNet outperforms state-of-the-art methods that\nrely on hand-engineered, high-level features. These results are particularly\nstriking because we train the method entirely on a significantly biased data\nset that does not account for the fact that proteins deform when binding to one\nanother. Demonstrating the first successful application of transfer learning to\natomic-level data, our network maintains high performance, without retraining,\nwhen tested on real cases in which proteins do deform.\n",
"title": "Transferrable End-to-End Learning for Protein Interface Prediction"
}
| null | null | null | null | true | null |
9853
| null |
Default
| null | null |
null |
{
"abstract": " We test whether advanced galaxy models and analysis techniques of simulations\ncan alleviate the Too Big To Fail problem (TBTF) for late-type galaxies, which\nstates that isolated dwarf galaxy kinematics imply that dwarfs live in\nlower-mass halos than is expected in a {\\Lambda}CDM universe. Furthermore, we\nwant to explain this apparent tension between theory and observations. To do\nthis, we use the MoRIA suite of dwarf galaxy simulations to investigate whether\nobservational effects are involved in TBTF for late-type field dwarf galaxies.\nTo this end, we create synthetic radio data cubes of the simulated MoRIA\ngalaxies and analyse their HI kinematics as if they were real, observed\ngalaxies. We find that for low-mass galaxies, the circular velocity profile\ninferred from the HI kinematics often underestimates the true circular velocity\nprofile, as derived directly from the enclosed mass. Fitting the HI kinematics\nof MoRIA dwarfs with a theoretical halo profile results in a systematic\nunderestimate of the mass of their host halos. We attribute this effect to the\nfact that the interstellar medium of a low-mass late-type dwarf is continuously\nstirred by supernova explosions into a vertically puffed-up, turbulent state to\nthe extent that the rotation velocity of the gas is simply no longer a good\ntracer of the underlying gravitational force field. If this holds true for real\ndwarf galaxies as well, it implies that they inhabit more massive dark matter\nhalos than would be inferred from their kinematics, solving TBTF for late-type\nfield dwarf galaxies.\n",
"title": "A new astrophysical solution to the Too Big To Fail problem - Insights from the MoRIA simulations"
}
| null | null | null | null | true | null |
9854
| null |
Default
| null | null |
null |
{
"abstract": " Friction plays a key role in manipulating objects. Most of what we do with\nour hands, and most of what robots do with their grippers, is based on the\nability to control frictional forces. This paper aims to better understand the\nvariability and predictability of planar friction. In particular, we focus on\nthe analysis of a recent dataset on planar pushing by Yu et al. [1] devised to\ncreate a data-driven footprint of planar friction.\nWe show in this paper how we can explain a significant fraction of the\nobserved unconventional phenomena, e.g., stochasticity and multi-modality, by\ncombining the effects of material non-homogeneity, anisotropy of friction and\nbiases due to data collection dynamics, hinting that the variability is\nexplainable but inevitable in practice.\nWe introduce an anisotropic friction model and conduct simulation experiments\ncomparing with more standard isotropic friction models. The anisotropic\nfriction between object and supporting surface results in convergence of\ninitial condition during the automated data collection. Numerical results\nconfirm that the anisotropic friction model explains the bias in the dataset\nand the apparent stochasticity in the outcome of a push. The fact that the data\ncollection process itself can originate biases in the collected datasets,\nresulting in deterioration of trained models, calls attention to the data\ncollection dynamics.\n",
"title": "Friction Variability in Planar Pushing Data: Anisotropic Friction and Data-collection Bias"
}
| null | null | null | null | true | null |
9855
| null |
Default
| null | null |
null |
{
"abstract": " Turkish Wikipedia Named-Entity Recognition and Text Categorization (TWNERTC)\ndataset is a collection of automatically categorized and annotated sentences\nobtained from Wikipedia. We constructed large-scale gazetteers by using a graph\ncrawler algorithm to extract relevant entity and domain information from a\nsemantic knowledge base, Freebase. The constructed gazetteers contains\napproximately 300K entities with thousands of fine-grained entity types under\n77 different domains. Since automated processes are prone to ambiguity, we also\nintroduce two new content specific noise reduction methodologies. Moreover, we\nmap fine-grained entity types to the equivalent four coarse-grained types:\nperson, loc, org, misc. Eventually, we construct six different dataset versions\nand evaluate the quality of annotations by comparing ground truths from human\nannotators. We make these datasets publicly available to support studies on\nTurkish named-entity recognition (NER) and text categorization (TC).\n",
"title": "Automatically Annotated Turkish Corpus for Named Entity Recognition and Text Categorization using Large-Scale Gazetteers"
}
| null | null | null | null | true | null |
9856
| null |
Default
| null | null |
null |
{
"abstract": " Bi-Intuitionistic Stable Tense Logics (BIST Logics) are tense logics with a\nKripke semantics where worlds in a frame are equipped with a pre-order as well\nas with an accessibility relation which is 'stable' with respect to this\npre-order. BIST logics are extensions of a logic, BiSKt, which arose in the\nsemantic context of hypergraphs, since a special case of the pre-order can\nrepresent the incidence structure of a hypergraph. In this paper we provide,\nfor the first time, a Hilbert-style axiomatisation of BISKt and prove the\nstrong completeness of BiSKt. We go on to prove strong completeness of a class\nof BIST logics obtained by extending BiSKt by formulas of a certain form.\nMoreover we show that the finite model property and the decidability hold for a\nclass of BIST logics.\n",
"title": "Strong Completeness and the Finite Model Property for Bi-Intuitionistic Stable Tense Logics"
}
| null | null | null | null | true | null |
9857
| null |
Default
| null | null |
null |
{
"abstract": " We demonstrate how students' use of modeling can be examined and assessed\nusing student notebooks collected from an upper-division electronics lab\ncourse. The use of models is a ubiquitous practice in undergraduate physics\neducation, but the process of constructing, testing, and refining these models\nis much less common. We focus our attention on a lab course that has been\ntransformed to engage students in this modeling process during lab activities.\nThe design of the lab activities was guided by a framework that captures the\ndifferent components of model-based reasoning, called the Modeling Framework\nfor Experimental Physics. We demonstrate how this framework can be used to\nassess students' written work and to identify how students' model-based\nreasoning differed from activity to activity. Broadly speaking, we were able to\nidentify the different steps of students' model-based reasoning and assess the\ncompleteness of their reasoning. Varying degrees of scaffolding present across\nthe activities had an impact on how thoroughly students would engage in the\nfull modeling process, with more scaffolded activities resulting in more\nthorough engagement with the process. Finally, we identified that the step in\nthe process with which students had the most difficulty was the comparison\nbetween their interpreted data and their model prediction. Students did not use\nsufficiently sophisticated criteria in evaluating such comparisons, which had\nthe effect of halting the modeling process. This may indicate that in order to\nengage students further in using model-based reasoning during lab activities,\nthe instructor needs to provide further scaffolding for how students make these\ntypes of experimental comparisons. This is an important design consideration\nfor other such courses attempting to incorporate modeling as a learning goal.\n",
"title": "Using lab notebooks to examine students' engagement in modeling in an upper-division electronics lab course"
}
| null | null | null | null | true | null |
9858
| null |
Default
| null | null |
null |
{
"abstract": " Despite its numerical challenges, finite element method is used to compute\nviscous fluid flow. A consensus on the cause of numerical problems has been\nreached; however, general algorithms---allowing a robust and accurate\nsimulation for any process---are still missing. Either a very high\ncomputational cost is necessary for a direct numerical solution (DNS) or some\nlimiting procedure is used by adding artificial dissipation to the system.\nThese stabilization methods are useful; however, they are often applied\nrelative to the element size such that a local monotonous convergence is\nchallenging to acquire. We need a computational strategy for solving viscous\nfluid flow using solely the balance equations. In this work, we present a\ngeneral procedure solving fluid mechanics problems without use of any\nstabilization or splitting schemes. Hence, its generalization to multiphysics\napplications is straightforward. We discuss emerging numerical problems and\npresent the methodology rigorously. Implementation is achieved by using\nopen-source packages and the accuracy as well as the robustness is demonstrated\nby comparing results to the closed-form solutions and also by solving\nwell-known benchmarking problems.\n",
"title": "An accurate finite element method for the numerical solution of isothermal and incompressible flow of viscous fluid"
}
| null | null |
[
"Computer Science",
"Physics"
] | null | true | null |
9859
| null |
Validated
| null | null |
null |
{
"abstract": " Progress in machine learning is measured by careful evaluation on problems of\noutstanding common interest. However, the proliferation of benchmark suites and\nenvironments, adversarial attacks, and other complications has diluted the\nbasic evaluation model by overwhelming researchers with choices. Deliberate or\naccidental cherry picking is increasingly likely, and designing well-balanced\nevaluation suites requires increasing effort. In this paper we take a step back\nand propose Nash averaging. The approach builds on a detailed analysis of the\nalgebraic structure of evaluation in two basic scenarios: agent-vs-agent and\nagent-vs-task. The key strength of Nash averaging is that it automatically\nadapts to redundancies in evaluation data, so that results are not biased by\nthe incorporation of easy tasks or weak agents. Nash averaging thus encourages\nmaximally inclusive evaluation -- since there is no harm (computational cost\naside) from including all available tasks and agents.\n",
"title": "Re-evaluating Evaluation"
}
| null | null | null | null | true | null |
9860
| null |
Default
| null | null |
null |
{
"abstract": " Under a Bayesian framework, we formulate the fully sequential sampling and\nselection decision in statistical ranking and selection as a stochastic control\nproblem, and derive the associated Bellman equation. Using value function\napproximation, we derive an approximately optimal allocation policy. We show\nthat this policy is not only computationally efficient but also possesses both\none-step-ahead and asymptotic optimality for independent normal sampling\ndistributions. Moreover, the proposed allocation policy is easily generalizable\nin the approximate dynamic programming paradigm.\n",
"title": "Ranking and Selection as Stochastic Control"
}
| null | null | null | null | true | null |
9861
| null |
Default
| null | null |
null |
{
"abstract": " The concept of a $\\Gamma$-semigroup has been introduced by Mridul Kanti Sen\nin the Int. Symp., New Delhi, 1981. It is well known that the Green's relations\nplay an essential role in studying the structure of semigroups. In the present\npaper we deal with an application of $\\Gamma$-semigroups techniques to the\nGreen's Theorem in an attempt to show the way we pass from semigroups to\n$\\Gamma$-semigroups.\n",
"title": "An application of $Γ$-semigroups techniques to the Green's Theorem"
}
| null | null |
[
"Mathematics"
] | null | true | null |
9862
| null |
Validated
| null | null |
null |
{
"abstract": " We formally deduce closed-form expressions for the transmitted effective\nwavenumber of a material comprising multiple types of inclusions or particles\n(multi-species), dispersed in a uniform background medium. The expressions,\nderived here for the first time, are valid for moderate volume fractions and\nwithout restriction on the frequency. We show that the multi-species effective\nwavenumber is not a straightforward extension of expressions for a single\nspecies. Comparisons are drawn with state-of-the-art models in acoustics by\npresenting numerical results for a concrete and a water-oil emulsion in two\ndimensions. The limit of when one species is much smaller than the other is\nalso discussed and we determine the background medium felt by the larger\nspecies in this limit. Surprisingly, we show that the answer is not the\nintuitive result predicted by self-consistent multiple scattering theories. The\nderivation presented here applies to the scalar wave equation with cylindrical\nor spherical inclusions, with any distribution of sizes, densities, and wave\nspeeds. The reflection coefficient associated with a half-space of\nmulti-species cylindrical inclusions is also formally derived.\n",
"title": "Reflection from a multi-species material and its transmitted effective wavenumber"
}
| null | null | null | null | true | null |
9863
| null |
Default
| null | null |
null |
{
"abstract": " A graph is perfect if the chromatic number of every induced subgraph equals\nthe size of its largest clique, and an algorithm of Grötschel, Lovász, and\nSchrijver from 1988 finds an optimal colouring of a perfect graph in polynomial\ntime. But this algorithm uses the ellipsoid method, and it is a well-known open\nquestion to construct a \"combinatorial\" polynomial-time algorithm that yields\nan optimal colouring of a perfect graph.\nA skew partition in $G$ is a partition $(A,B)$ of $V(G)$ such that $G[A]$ is\nnot connected and $\\bar{G}[B]$ is not connected, where $\\bar{G}$ denotes the\ncomplement graph ; and it is balanced if an additional parity condition of\npaths in $G$ and $\\bar{G}$ is satisfied.\nIn this paper we first give a polynomial-time algorithm that, with input a\nperfect graph, outputs a balanced skew partition if there is one. Then we use\nthis to obtain a combinatorial algorithm that finds an optimal colouring of a\nperfect graph with clique number $k$, in time that is polynomial for fixed $k$.\n",
"title": "Colouring perfect graphs with bounded clique number"
}
| null | null | null | null | true | null |
9864
| null |
Default
| null | null |
null |
{
"abstract": " In this paper, we show synchronization for a group of output passive agents\nthat communicate with each other according to an underlying communication graph\nto achieve a common goal. We propose a distributed event-triggered control\nframework that will guarantee synchronization and considerably decrease the\nrequired communication load on the band-limited network. We define a general\nByzantine attack on the event-triggered multi-agent network system and\ncharacterize its negative effects on synchronization. The Byzantine agents are\ncapable of intelligently falsifying their data and manipulating the underlying\ncommunication graph by altering their respective control feedback weights. We\nintroduce a decentralized detection framework and analyze its steady-state and\ntransient performances. We propose a way of identifying individual Byzantine\nneighbors and a learning-based method of estimating the attack parameters.\nLastly, we propose learning-based control approaches to mitigate the negative\neffects of the adversarial attack.\n",
"title": "Resilient Learning-Based Control for Synchronization of Passive Multi-Agent Systems under Attack"
}
| null | null | null | null | true | null |
9865
| null |
Default
| null | null |
null |
{
"abstract": " We present a method for EMG-driven teleoperation of non-anthropomorphic robot\nhands. EMG sensors are appealing as a wearable, inexpensive and unobtrusive way\nto gather information about the teleoperator's hand pose. However, mapping from\nEMG signals to the pose space of a non-anthropomorphic hand presents multiple\nchallenges. We present a method that first projects from forearm EMG into a\nsubspace relevant to teleoperation. To increase robustness, we use a model\nwhich combines continuous and discrete predictors along different dimensions of\nthis subspace. We then project from the teleoperation subspace into the pose\nspace of the robot hand. We show that our method is effective and intuitive, as\nit enables novice users to teleoperate pick and place tasks faster and more\nrobustly than state-of-the-art EMG teleoperation methods when applied to a\nnon-anthropomorphic, multi-DOF robot hand.\n",
"title": "EMG-Controlled Hand Teleoperation Using a Continuous Teleoperation Subspace"
}
| null | null | null | null | true | null |
9866
| null |
Default
| null | null |
null |
{
"abstract": " We introduce a novel numerical method to integrate partial differential\nequations representing the Hamiltonian dynamics of field theories. It is a\nmulti-symplectic integrator that locally conserves the stress-energy tensor\nwith an excellent precision over very long periods. Its major advantage is that\nit is extremely simple (it is basically a centered box scheme) while remaining\nlocally well defined. We put it to the test in the case of the non-linear wave\nequation (with quartic potential) in one spatial dimension, and we explain how\nto implement it in higher dimensions. A formal geometric presentation of the\nmulti-symplectic structure is also given as well as a technical trick allowing\nto solve the degeneracy problem that potentially accompanies the\nmulti-symplectic structure.\n",
"title": "Numerical solutions of Hamiltonian PDEs: a multi-symplectic integrator in light-cone coordinates"
}
| null | null | null | null | true | null |
9867
| null |
Default
| null | null |
null |
{
"abstract": " X-ray magnetic circular dichroism (XMCD) measurements of iron nano-islands\ngrown on graphene and covered with a Au film for passivation reveal that the\noxidation through defects in the Au film spontaneously leads to the formation\nof magnetite nano-particles (i.e, $Fe_3$$O_4$). The Fe nano-islands (20 and 75\nmonolayers; MLs) are grown on epitaxial graphene formed by thermally annealing\n6H-SiC(0001) and subsequently covered, in the growth chamber, with nominal 20\nlayers of Au. Our X-ray absorption spectroscopy and XMCD measurements at\napplied magnetic fields show that the thin film (20 ML) is totally converted to\nmagnetite whereas the thicker film (75 ML) exhibits properties of magnetite but\nalso those of pure metallic iron. Temperature dependence of the XMCD signal (of\nboth samples) shows a clear transition at $T_{\\rm V}\\approx 120$ K consistent\nwith the Verwey transition of bulk magnetite. These results have implications\non the synthesis of magnetite nano-crystals and also on their regular\narrangements on functional substrates such as graphene.\n",
"title": "Magnetite nano-islands on silicon-carbide with graphene"
}
| null | null | null | null | true | null |
9868
| null |
Default
| null | null |
null |
{
"abstract": " Many activation functions have been proposed in the past, but selecting an\nadequate one requires trial and error. We propose a new methodology of\ndesigning activation functions within a neural network at each layer. We call\nthis technique an \"activation ensemble\" because it allows the use of multiple\nactivation functions at each layer. This is done by introducing additional\nvariables, $\\alpha$, at each activation layer of a network to allow for\nmultiple activation functions to be active at each neuron. By design,\nactivations with larger $\\alpha$ values at a neuron is equivalent to having the\nlargest magnitude. Hence, those higher magnitude activations are \"chosen\" by\nthe network. We implement the activation ensembles on a variety of datasets\nusing an array of Feed Forward and Convolutional Neural Networks. By using the\nactivation ensemble, we achieve superior results compared to traditional\ntechniques. In addition, because of the flexibility of this methodology, we\nmore deeply explore activation functions and the features that they capture.\n",
"title": "Activation Ensembles for Deep Neural Networks"
}
| null | null | null | null | true | null |
9869
| null |
Default
| null | null |
null |
{
"abstract": " Traditionally social sciences are interested in structuring people in\nmultiple groups based on their individual preferences. This pa- per suggests an\napproach to this problem in the framework of a non- cooperative game theory.\nDefinition of a suggested finite game includes a family of nested simultaneous\nnon-cooperative finite games with intra- and inter-coalition externalities. In\nthis family, games differ by the size of maximum coalition, partitions and by\ncoalition structure formation rules. A result of every game consists of\npartition of players into coalitions and a payoff? profiles for every player.\nEvery game in the family has an equilibrium in mixed strategies with possibly\nmore than one coalition. The results of the game differ from those\nconventionally discussed in cooperative game theory, e.g. the Shapley value,\nstrong Nash, coalition-proof equilibrium, core, kernel, nucleolus. We discuss\nthe following applications of the new game: cooperation as an allocation in one\ncoalition, Bayesian games, stochastic games and construction of a\nnon-cooperative criterion of coalition structure stability for studying focal\npoints.\n",
"title": "Formation of coalition structures as a non-cooperative game"
}
| null | null |
[
"Computer Science",
"Mathematics"
] | null | true | null |
9870
| null |
Validated
| null | null |
null |
{
"abstract": " Entropic regularization is quickly emerging as a new standard in optimal\ntransport (OT). It enables to cast the OT computation as a differentiable and\nunconstrained convex optimization problem, which can be efficiently solved\nusing the Sinkhorn algorithm. However, entropy keeps the transportation plan\nstrictly positive and therefore completely dense, unlike unregularized OT. This\nlack of sparsity can be problematic in applications where the transportation\nplan itself is of interest. In this paper, we explore regularizing the primal\nand dual OT formulations with a strongly convex term, which corresponds to\nrelaxing the dual and primal constraints with smooth approximations. We show\nhow to incorporate squared $2$-norm and group lasso regularizations within that\nframework, leading to sparse and group-sparse transportation plans. On the\ntheoretical side, we bound the approximation error introduced by regularizing\nthe primal and dual formulations. Our results suggest that, for the regularized\nprimal, the approximation error can often be smaller with squared $2$-norm than\nwith entropic regularization. We showcase our proposed framework on the task of\ncolor transfer.\n",
"title": "Smooth and Sparse Optimal Transport"
}
| null | null |
[
"Computer Science",
"Statistics"
] | null | true | null |
9871
| null |
Validated
| null | null |
null |
{
"abstract": " The eigenvalue of the hermitic Hamiltonian is real undoubtedly. Actually, The\nreality can also be guaranteed by the $PT$-symmetry. The hermiticity and the\n$PT$-symmetric quantum theory both have requirements regarding the boundary\ncondition. There exists a reverse strategy to investigate the quantum problem.\nNamely, define the eigenvalue as real first, and, meanwhile, open the boundary\ncondition. Then the behaviors of the wave function at the boundary become rich\nin meaning. This eigenfunction is generally divergent, and the extent and\ndirection of divergence are closely linked to the energy. It was noted that\nthese divergent behaviors can be well described by their energy-space\nuncertainty relation which is not trivial anymore. The divergent state is\nunstable and will certainly exchange energy with the outside. The mechanism of\nenergy exchange is just in the energy-space uncertainty relation, which will\nbenefit dynamic simulation, the many-body problem, and so on. There is no\ndistinct dividing line between this kind of divergent unstable state and the\nconvergent stable state. Their relationship is like that of the rational and\nirrational numbers. In practice, there are distinct advantages of speed and\naccuracy for the methods based on the laws of divergence.\n",
"title": "The stability and energy exchange mechanism of divergent states with real energy"
}
| null | null | null | null | true | null |
9872
| null |
Default
| null | null |
null |
{
"abstract": " Let $X$ be a finite collection of sets (or \"clusters\"). We consider the\nproblem of counting the number of ways a cluster $A \\in X$ can be partitioned\ninto two disjoint clusters $A_1, A_2 \\in X$, thus $A = A_1 \\uplus A_2$ is the\ndisjoint union of $A_1$ and $A_2$; this problem arises in the run time analysis\nof the ASTRAL algorithm in phylogenetic reconstruction. We obtain the bound $$\n| \\{ (A_1,A_2,A) \\in X \\times X \\times X: A = A_1 \\uplus A_2 \\} | \\leq\n|X|^{3/p} $$ where $|X|$ denotes the cardinality of $X$, and $p := \\log_3\n\\frac{27}{4} = 1.73814\\dots$, so that $\\frac{3}{p} = 1.72598\\dots$.\nFurthermore, the exponent $p$ cannot be replaced by any larger quantity. This\nimproves upon the trivial bound of $|X|^2$. The argument relies on establishing\na one-dimensional convolution inequality that can be established by elementary\ncalculus combined with some numerical verification.\nIn a similar vein, we show that for any subset $A$ of a discrete cube\n$\\{0,1\\}^n$, the additive energy of $A$ (the number of quadruples\n$(a_1,a_2,a_3,a_4)$ in $A^4$ with $a_1+a_2=a_3+a_4$) is at most $|A|^{\\log_2\n6}$, and that this exponent is best possible.\n",
"title": "A bound on partitioning clusters"
}
| null | null | null | null | true | null |
9873
| null |
Default
| null | null |
null |
{
"abstract": " Every observation of astrophysical objects involving a spectrum requires\natomic data for the interpretation of line fluxes, line ratios and ionization\nstate of the emitting plasma. One of the processes which determines it is\ncollisional ionization. In this study an update of the direct ionization (DI)\nand excitation-autoionization (EA) processes is discussed for the H to Zn-like\nisoelectronic sequences. In the last years new laboratory measurements and\ntheoretical calculations of ionization cross sections have become available. We\nprovide an extension and update of previous published reviews in the\nliterature. We include the most recent experimental measurements and fit the\ncross sections of all individual shells of all ions from H to Zn. These data\nare described using an extension of Younger's and Mewe's formula, suitable for\nintegration over a Maxwellian velocity distribution to derive the subshell\nionization rate coefficients. These ionization rate coefficients are\nincorporated in the high-resolution plasma code and spectral fitting tool SPEX\nV3.0.\n",
"title": "X-ray emission from thin plasmas. Collisional ionization for atoms and ions of H to Zn"
}
| null | null | null | null | true | null |
9874
| null |
Default
| null | null |
null |
{
"abstract": " We generalize a support vector machine to a support spinor machine by using\nthe mathematical structure of wedge product over vector machine in order to\nextend field from vector field to spinor field. The separated hyperplane is\nextended to Kolmogorov space in time series data which allow us to extend a\nstructure of support vector machine to a support tensor machine and a support\ntensor machine moduli space. Our performance test on support spinor machine is\ndone over one class classification of end point in physiology state of time\nseries data after empirical mode analysis and compared with support vector\nmachine test. We implement algorithm of support spinor machine by using\nHolo-Hilbert amplitude modulation for fully nonlinear and nonstationary time\nseries data analysis.\n",
"title": "Support Spinor Machine"
}
| null | null |
[
"Computer Science",
"Statistics"
] | null | true | null |
9875
| null |
Validated
| null | null |
null |
{
"abstract": " Recall that the group $PSL(2,\\mathbb R)$ is isomorphic to $PSp(2,\\mathbb R),\\\nSO_0(1,2)$ and $PU(1,1).$ The goal of this paper is to examine the various ways\nin which Fuchsian representations of the fundamental group of a closed surface\nof genus $g$ into $PSL(2,\\mathbb R)$ and their associated Higgs bundles\ngeneralize to the higher rank groups $PSL(n,\\mathbb R),\\ PSp(2n,\\mathbb R),\\\nSO_0(2,n),\\ SO_0(n,n+1)$ and $PU(n,n)$. For the $SO_0(n,n+1)$-character\nvariety, we parameterize $n(2g-2)$ new connected components as the total space\nof vector bundles over appropriate symmetric powers of the surface and study\nhow these components deform in the $SO_0(n,n+2)$-character variety. This\ngeneralizes results of Hitchin for $PSL(2,\\mathbb R)$.\n",
"title": "Various generalizations and deformations of $PSL(2,\\mathbb{R})$ surface group representations and their Higgs bundles"
}
| null | null |
[
"Mathematics"
] | null | true | null |
9876
| null |
Validated
| null | null |
null |
{
"abstract": " This paper proposes a signature-based approach for solving redundancy\nallocation problems when component lifetimes are not only heterogeneous but\nalso dependent. The two common schemes for allocations, that is active and\nstandby redundancies, are considered. If the component lifetimes are\nindependent, the proposed approach leads to simple manipulations. Various\nillustrative examples are also analysed. This method can be implemented for\npractical complex engineering systems.\n",
"title": "Redundancy schemes for engineering coherent systems via a signature-based approach"
}
| null | null | null | null | true | null |
9877
| null |
Default
| null | null |
null |
{
"abstract": " We study the $f(R)$ theory of gravity in an anisotropic metric and its effect\non the baryon number to entropy ratio. The mechanism of gravitational\nbaryogenesis based on the CPT-violating gravitational interaction between\nderivative of the Ricci scalar curvature and the baryon-number current is\ninvestigated in the context of the $f(R)$ gravity. The gravitational\nbaryogenesis in the Bianchi type I universe is examined. We survey the effect\nof anisotropy of the universe on the baryon asymmetry from point of view the\n$f(R)$-theories of gravity and its effect on $n_{b}/s$ for radiation dominant\nregime.\n",
"title": "Anisotropy effects on Baryogenesis in $f(R)$-Theories of Gravity"
}
| null | null | null | null | true | null |
9878
| null |
Default
| null | null |
null |
{
"abstract": " Visual tracking is a fundamental problem in computer vision. Recently, some\ndeep-learning-based tracking algorithms have been achieving record-breaking\nperformances. However, due to the high complexity of deep learning, most deep\ntrackers suffer from low tracking speed, and thus are impractical in many\nreal-world applications. Some new deep trackers with smaller network structure\nachieve high efficiency while at the cost of significant decrease on precision.\nIn this paper, we propose to transfer the feature for image classification to\nthe visual tracking domain via convolutional channel reductions. The channel\nreduction could be simply viewed as an additional convolutional layer with the\nspecific task. It not only extracts useful information for object tracking but\nalso significantly increases the tracking speed. To better accommodate the\nuseful feature of the target in different scales, the adaptation filters are\ndesigned with different sizes. The yielded visual tracker is real-time and also\nillustrates the state-of-the-art accuracies in the experiment involving two\nwell-adopted benchmarks with more than 100 test videos.\n",
"title": "Robust and Real-time Deep Tracking Via Multi-Scale Domain Adaptation"
}
| null | null | null | null | true | null |
9879
| null |
Default
| null | null |
null |
{
"abstract": " We design a deterministic polynomial time $c^n$ approximation algorithm for\nthe permanent of positive semidefinite matrices where $c=e^{\\gamma+1}\\simeq\n4.84$. We write a natural convex relaxation and show that its optimum solution\ngives a $c^n$ approximation of the permanent. We further show that this factor\nis asymptotically tight by constructing a family of positive semidefinite\nmatrices.\n",
"title": "Simply Exponential Approximation of the Permanent of Positive Semidefinite Matrices"
}
| null | null | null | null | true | null |
9880
| null |
Default
| null | null |
null |
{
"abstract": " Recent advances in policy gradient methods and deep learning have\ndemonstrated their applicability for complex reinforcement learning problems.\nHowever, the variance of the performance gradient estimates obtained from the\nsimulation is often excessive, leading to poor sample efficiency. In this\npaper, we apply the stochastic variance reduced gradient descent (SVRG) to\nmodel-free policy gradient to significantly improve the sample-efficiency. The\nSVRG estimation is incorporated into a trust-region Newton conjugate gradient\nframework for the policy optimization. On several Mujoco tasks, our method\nachieves significantly better performance compared to the state-of-the-art\nmodel-free policy gradient methods in robotic continuous control such as trust\nregion policy optimization (TRPO)\n",
"title": "Stochastic Variance Reduction for Policy Gradient Estimation"
}
| null | null |
[
"Computer Science",
"Statistics"
] | null | true | null |
9881
| null |
Validated
| null | null |
null |
{
"abstract": " We primarily study a special a weighted low-rank approximation of matrices\nand then apply it to solve the background modeling problem. We propose two\nalgorithms for this purpose: one operates in the batch mode on the entire data\nand the other one operates in the batch-incremental mode on the data and\nnaturally captures more background variations and computationally more\neffective. Moreover, we propose a robust technique that learns the background\nframe indices from the data and does not require any training frames. We\ndemonstrate through extensive experiments that by inserting a simple weight in\nthe Frobenius norm, it can be made robust to the outliers similar to the\n$\\ell_1$ norm. Our methods match or outperform several state-of-the-art online\nand batch background modeling methods in virtually all quantitative and\nqualitative measures.\n",
"title": "Weighted Low-Rank Approximation of Matrices and Background Modeling"
}
| null | null | null | null | true | null |
9882
| null |
Default
| null | null |
null |
{
"abstract": " We derive the Markov process equivalent to She-Leveque scaling in homogeneous\nand isotropic turbulence. The Markov process is a jump process for velocity\nincrements $u(r)$ in scale $r$ in which the jumps occur randomly but with\ndeterministic width in $u$. From its master equation we establish a\nprescription to simulate the She-Leveque process and compare it with Kolmogorov\nscaling. To put the She-Leveque process into the context of other established\nturbulence models on the Markov level, we derive a diffusion process for $u(r)$\nfrom two properties of the Navier-Stokes equation. This diffusion process\nalready includes Kolmogorov scaling, extended self-similarity and a class of\nrandom cascade models. The fluctuation theorem of this Markov process implies a\n\"second law\" that puts a loose bound on the multipliers of the random cascade\nmodels. This bound explicitly allows for inverse cascades, which are necessary\nto satisfy the fluctuation theorem. By adding a jump process to the diffusion\nprocess, we go beyond Kolmogorov scaling and formulate the most general scaling\nlaw for the class of Markov processes having both diffusion and jump parts.\nThis Markov scaling law includes She-Leveque scaling and a scaling law derived\nby Yakhot.\n",
"title": "Master equation for She-Leveque scaling and its classification in terms of other Markov models of developed turbulence"
}
| null | null | null | null | true | null |
9883
| null |
Default
| null | null |
null |
{
"abstract": " The dynamic Mott insulator-to-metal transition (DMT) is key to many\nintriguing phenomena in condensed matter physics yet it remains nearly\nunexplored. The cleanest way to observe DMT, without the interference from\ndisorder and other effects inherent to electronic and atomic systems, is to\nemploy the vortex Mott states formed by superconducting vortices in a regular\narray of pinning sites. The applied electric current delocalizes vortices and\ndrives the dynamic vortex Mott transition. Here we report the critical behavior\nof the vortex system as it crosses the DMT line, driven by either current or\ntemperature. We find universal scaling with respect to both, expressed by the\nsame scaling function and characterized by a single critical exponent\ncoinciding with the exponent for the thermodynamic Mott transition. We develop\na theory for the DMT based on the parity reflection-time reversal (PT) symmetry\nbreaking formalism and find that the nonequilibrium-induced Mott transition has\nthe same critical behavior as thermal Mott transition. Our findings demonstrate\nthe existence of physical systems in which the effect of nonequilibrium drive\nis to generate effective temperature and hence the transition belonging in the\nthermal universality class. We establish PT symmetry-breaking as a universal\nmechanism for out-of-equilibrium phase transitions.\n",
"title": "Scaling Universality at the Dynamic Vortex Mott Transition"
}
| null | null | null | null | true | null |
9884
| null |
Default
| null | null |
null |
{
"abstract": " Although compelling assessments have been examined in recent years, more\nstudies are required to yield a better understanding of the several methods\nwhere assessment techniques significantly affect student learning process. Most\nof the educational research in this area does not consider demographics data,\ndiffering methodologies, and notable sample size. To address these drawbacks,\nthe objective of our study is to analyse student learning outcomes of multiple\nassessment formats for a web-facilitated in-class section with an asynchronous\nonline class of a core data communications course in the Undergraduate IT\nprogram of the Information Sciences and Technology (IST) Department at George\nMason University (GMU). In this study, students were evaluated based on course\nassessments such as home and lab assignments, skill-based assessments, and\ntraditional midterm and final exams across all four sections of the course. All\nsections have equivalent content, assessments, and teaching methodologies.\nStudent demographics such as exam type and location preferences are considered\nin our study to determine whether they have any impact on their learning\napproach. Large amount of data from the learning management system (LMS),\nBlackboard (BB) Learn, had to be examined to compare the results of several\nassessment outcomes for all students within their respective section and\namongst students of other sections. To investigate the effect of dissimilar\nassessment formats on student performance, we had to correlate individual\nquestion formats with the overall course grade. The results show that\ncollective assessment formats allow students to be effective in demonstrating\ntheir knowledge.\n",
"title": "Assessment Formats and Student Learning Performance: What is the Relation?"
}
| null | null | null | null | true | null |
9885
| null |
Default
| null | null |
null |
{
"abstract": " Decoding human brain activities via functional magnetic resonance imaging\n(fMRI) has gained increasing attention in recent years. While encouraging\nresults have been reported in brain states classification tasks, reconstructing\nthe details of human visual experience still remains difficult. Two main\nchallenges that hinder the development of effective models are the perplexing\nfMRI measurement noise and the high dimensionality of limited data instances.\nExisting methods generally suffer from one or both of these issues and yield\ndissatisfactory results. In this paper, we tackle this problem by casting the\nreconstruction of visual stimulus as the Bayesian inference of missing view in\na multiview latent variable model. Sharing a common latent representation, our\njoint generative model of external stimulus and brain response is not only\n\"deep\" in extracting nonlinear features from visual images, but also powerful\nin capturing correlations among voxel activities of fMRI recordings. The\nnonlinearity and deep structure endow our model with strong representation\nability, while the correlations of voxel activities are critical for\nsuppressing noise and improving prediction. We devise an efficient variational\nBayesian method to infer the latent variables and the model parameters. To\nfurther improve the reconstruction accuracy, the latent representations of\ntesting instances are enforced to be close to that of their neighbours from the\ntraining set via posterior regularization. Experiments on three fMRI recording\ndatasets demonstrate that our approach can more accurately reconstruct visual\nstimuli.\n",
"title": "Sharing deep generative representation for perceived image reconstruction from human brain activity"
}
| null | null | null | null | true | null |
9886
| null |
Default
| null | null |
null |
{
"abstract": " Neural networks with equal excitatory and inhibitory feedback show high\ncomputational performance. They operate close to a critical point characterized\nby the joint activation of large populations of neurons. Yet, in macaque motor\ncortex we observe very different dynamics with weak fluctuations on the\npopulation level. This suggests that motor cortex operates in a sub-optimal\nregime. Here we show the opposite: the large dispersion of correlations across\nneurons is a signature of a rich dynamical repertoire, hidden from macroscopic\nbrain signals, but essential for high performance in such concepts as reservoir\ncomputing. Our findings suggest a refinement of the view on criticality in\nneural systems: network topology and heterogeneity endow the brain with two\ncomplementary substrates for critical dynamics of largely different\ncomplexities.\n",
"title": "Two types of criticality in the brain"
}
| null | null |
[
"Physics"
] | null | true | null |
9887
| null |
Validated
| null | null |
null |
{
"abstract": " Efficient communication between qubits relies on robust networks which allow\nfor fast and coherent transfer of quantum information. It seems natural to\nharvest the remarkable properties of systems characterized by topological\ninvariants to perform this task. Here we show that a linear network of coupled\nbosonic degrees of freedom, characterized by topological bands, can be employed\nfor the efficient exchange of quantum information over large distances.\nImportant features of our setup are that it is robust against quenched\ndisorder, all relevant operations can be performed by global variations of\nparameters, and the time required for communication between distant qubits\napproaches linear scaling with their distance. We demonstrate that our concept\ncan be extended to an ensemble of qubits embedded in a two-dimensional network\nto allow for communication between all of them.\n",
"title": "Topological networks for quantum communication between distant qubits"
}
| null | null | null | null | true | null |
9888
| null |
Default
| null | null |
null |
{
"abstract": " Whereas the relationship between criticality of gene regulatory networks\n(GRNs) and dynamics of GRNs at a single cell level has been vigorously studied,\nthe relationship between the criticality of GRNs and system properties at a\nhigher level has remained unexplored. Here we aim at revealing a potential role\nof criticality of GRNs at a multicellular level which are hard to uncover\nthrough the single-cell-level studies, especially from an evolutionary\nviewpoint. Our model simulated the growth of a cell population from a single\nseed cell. All the cells were assumed to have identical GRNs. We induced\ngenetic perturbations to the GRN of the seed cell by adding, deleting, or\nswitching a regulatory link between a pair of genes. From numerical\nsimulations, we found that the criticality of GRNs facilitated the formation of\nnontrivial morphologies when the GRNs were critical in the presence of the\nevolutionary perturbations. Moreover, the criticality of GRNs produced\ntopologically homogenous cell clusters by adjusting the spatial arrangements of\ncells, which led to the formation of nontrivial morphogenetic patterns. Our\nfindings corresponded to an epigenetic viewpoint that heterogeneous and complex\nfeatures emerge from homogeneous and less complex components through the\ninteractions among them. Thus, our results imply that highly structured tissues\nor organs in morphogenesis of multicellular organisms might stem from the\ncriticality of GRNs.\n",
"title": "How Criticality of Gene Regulatory Networks Affects the Resulting Morphogenesis under Genetic Perturbations"
}
| null | null | null | null | true | null |
9889
| null |
Default
| null | null |
null |
{
"abstract": " Feed-forward convolutional neural networks (CNNs) are currently\nstate-of-the-art for object classification tasks such as ImageNet. Further,\nthey are quantitatively accurate models of temporally-averaged responses of\nneurons in the primate brain's visual system. However, biological visual\nsystems have two ubiquitous architectural features not shared with typical\nCNNs: local recurrence within cortical areas, and long-range feedback from\ndownstream areas to upstream areas. Here we explored the role of recurrence in\nimproving classification performance. We found that standard forms of\nrecurrence (vanilla RNNs and LSTMs) do not perform well within deep CNNs on the\nImageNet task. In contrast, novel cells that incorporated two structural\nfeatures, bypassing and gating, were able to boost task accuracy substantially.\nWe extended these design principles in an automated search over thousands of\nmodel architectures, which identified novel local recurrent cells and\nlong-range feedback connections useful for object recognition. Moreover, these\ntask-optimized ConvRNNs matched the dynamics of neural activity in the primate\nvisual system better than feedforward networks, suggesting a role for the\nbrain's recurrent connections in performing difficult visual behaviors.\n",
"title": "Task-Driven Convolutional Recurrent Models of the Visual System"
}
| null | null | null | null | true | null |
9890
| null |
Default
| null | null |
null |
{
"abstract": " Dynamic patterning of specific proteins is essential for the spatiotemporal\nregulation of many important intracellular processes in procaryotes,\neucaryotes, and multicellular organisms. The emergence of patterns generated by\ninteractions of diffusing proteins is a paradigmatic example for\nself-organization. In this article we review quantitative models for\nintracellular Min protein patterns in E. coli, Cdc42 polarization in S.\ncerevisiae, and the bipolar PAR protein patterns found in C. elegans. By\nanalyzing the molecular processes driving these systems we derive a theoretical\nperspective on general principles underlying self-organized pattern formation.\nWe argue that intracellular pattern formation is not captured by concepts such\nas \"activators\"', \"inhibitors\", or \"substrate-depletion\". Instead,\nintracellular pattern formation is based on the redistribution of proteins by\ncytosolic diffusion, and the cycling of proteins between distinct\nconformational states. Therefore, mass-conserving reaction-diffusion equations\nprovide the most appropriate framework to study intracellular pattern\nformation. We conclude that directed transport, e.g. cytosolic diffusion along\nan actively maintained cytosolic gradient, is the key process underlying\npattern formation. Thus the basic principle of self-organization is the\nestablishment and maintenance of directed transport by intracellular protein\ndynamics.\n",
"title": "Self-organization principles of intracellular pattern formation"
}
| null | null | null | null | true | null |
9891
| null |
Default
| null | null |
null |
{
"abstract": " If we pick $n$ random points uniformly in $[0,1]^d$ and connect each point to\nits $k-$nearest neighbors, then it is well known that there exists a giant\nconnected component with high probability. We prove that in $[0,1]^d$ it\nsuffices to connect every point to $ c_{d,1} \\log{\\log{n}}$ points chosen\nrandomly among its $ c_{d,2} \\log{n}-$nearest neighbors to ensure a giant\ncomponent of size $n - o(n)$ with high probability. This construction yields a\nmuch sparser random graph with $\\sim n \\log\\log{n}$ instead of $\\sim n \\log{n}$\nedges that has comparable connectivity properties. This result has nontrivial\nimplications for problems in data science where an affinity matrix is\nconstructed: instead of picking the $k-$nearest neighbors, one can often pick\n$k' \\ll k$ random points out of the $k-$nearest neighbors without sacrificing\nefficiency. This can massively simplify and accelerate computation, we\nillustrate this with several numerical examples.\n",
"title": "Randomized Near Neighbor Graphs, Giant Components, and Applications in Data Science"
}
| null | null | null | null | true | null |
9892
| null |
Default
| null | null |
null |
{
"abstract": " The formation of self-organized patterns is key to the morphogenesis of\nmulticellular organisms, although a comprehensive theory of biological pattern\nformation is still lacking. Here, we propose a minimal model combining tissue\nmechanics to morphogen turnover and transport in order to explore new routes to\npatterning. Our active description couples morphogen reaction-diffusion, which\nimpact on cell differentiation and tissue mechanics, to a two-phase poroelastic\nrheology, where one tissue phase consists of a poroelastic cell network and the\nother of a permeating extracellular fluid, which provides a feedback by\nactively transporting morphogens. While this model encompasses previous\ntheories approximating tissues to inert monophasic media, such as Turing's\nreaction-diffusion model, it overcomes some of their key limitations permitting\npattern formation via any two-species biochemical kinetics thanks to\nmechanically induced cross-diffusion flows. Moreover, we describe a\nqualitatively different advection-driven Keller-Segel instability which allows\nfor the formation of patterns with a single morphogen, and whose fundamental\nmode pattern robustly scales with tissue size. We discuss the potential\nrelevance of these findings for tissue morphogenesis.\n",
"title": "Theory of mechano-chemical patterning in biphasic biological tissues"
}
| null | null | null | null | true | null |
9893
| null |
Default
| null | null |
null |
{
"abstract": " Biophysical modelling of diffusion MRI is necessary to provide specific\nmicrostructural tissue properties. However, estimating model parameters from\ndata with limited diffusion gradient strength, such as clinical scanners, has\nproven unreliable due to a shallow optimization landscape. On the other hand,\nestimation of diffusion kurtosis (DKI) parameters is more robust as the\nclinical acquisitions typically probe a regime in which the associated 4th\norder cumulant expansion is adequate; however, its parameters are not\nmicrostructurally specific a priori. Given an appropriate biophysical model,\nits parameters may be connected to DKI parameters, but it was previously shown\nthat at the DKI level, it still does not provide sufficient information to\nuniquely determine all model parameters. Earlier work has shown that by\nneglecting axonal dispersion, this parameter degeneracy reduces to the question\nof whether intra-axonal diffusivity is larger than or smaller than extra-axonal\ndiffusivity. Here we develop a model of diffusion in spinal cord white matter\nincluding axonal dispersion and demonstrate stable estimation of all model\nparameters from DKI. By employing the recently developed fast axisymmetric DKI,\nwe use stimulated echo acquisition mode to collect data over an unprecedented\ndiffusion time range with very narrow diffusion gradient pulses, enabling\nfinely resolved measurements of diffusion time dependence of both net diffusion\nand kurtosis metrics, as well as model intra- and extra-axonal diffusivities,\nand axonal dispersion. Our results demonstrate substantial time dependence of\nall parameters except volume fractions, and the additional time dimension\nprovides support for intra-axonal diffusivity to be larger than extra-axonal\ndiffusivity in spinal cord white matter, although not unambiguously. We compare\nour findings to predictions from effective medium theory.\n",
"title": "Diffusion time dependence of microstructural parameters in fixed spinal cord"
}
| null | null | null | null | true | null |
9894
| null |
Default
| null | null |
null |
{
"abstract": " This paper shows that conditional independence reasoning can be applied to\noptimize epistemic model checking, in which one verifies that a model for a\nnumber of agents operating with imperfect information satisfies a formula\nexpressed in a modal multi-agent logic of knowledge. The optimization has been\nimplemented in the epistemic model checker MCK. The paper reports experimental\nresults demonstrating that it can yield multiple orders of magnitude\nperformance improvements.\n",
"title": "Optimizing Epistemic Model Checking Using Conditional Independence (Extended Abstract)"
}
| null | null |
[
"Computer Science"
] | null | true | null |
9895
| null |
Validated
| null | null |
null |
{
"abstract": " Agile localization of anomalous events plays a pivotal role in enhancing the\noverall reliability of the grid and avoiding cascading failures. This is\nespecially of paramount significance in the large-scale grids due to their\ngeographical expansions and the large volume of data generated. This paper\nproposes a stochastic graphical framework, by leveraging which it aims to\nlocalize the anomalies with the minimum amount of data. This framework\ncapitalizes on the strong correlation structures observed among the\nmeasurements collected from different buses. The proposed approach, at its\ncore, collects the measurements sequentially and progressively updates its\ndecision about the location of the anomaly. The process resumes until the\nlocation of the anomaly can be identified with desired reliability. We provide\na general theory for the quickest anomaly localization and also investigate its\napplication for quickest line outage localization. Simulations in the IEEE\n118-bus model are provided to establish the gains of the proposed approach.\n",
"title": "Quickest Localization of Anomalies in Power Grids: A Stochastic Graphical Framework"
}
| null | null | null | null | true | null |
9896
| null |
Default
| null | null |
null |
{
"abstract": " The tensor train decomposition decomposes a tensor into a \"train\" of 3-way\ntensors that are interconnected through the summation of auxiliary indices. The\ndecomposition is stable, has a well-defined notion of rank and enables the user\nto perform various linear algebra operations on vectors and matrices of\nexponential size in a computationally efficient manner. The tensor ring\ndecomposition replaces the train by a ring through the introduction of one\nadditional auxiliary variable. This article discusses a major issue with the\ntensor ring decomposition: its inability to compute an exact minimal-rank\ndecomposition from a decomposition with sub-optimal ranks. Both the contraction\noperation and Hadamard product are motivated from applications and it is shown\nthrough simple examples how the tensor ring-rounding procedure fails to\nretrieve minimal-rank decompositions with these operations. These observations,\ntogether with the already known issue of not being able to find a best low-rank\ntensor ring approximation to a given tensor indicate that the applicability of\ntensor rings is severely limited.\n",
"title": "The trouble with tensor ring decompositions"
}
| null | null | null | null | true | null |
9897
| null |
Default
| null | null |
null |
{
"abstract": " Understanding the thermally activated escape from a metastable state is at\nthe heart of important phenomena such as the folding dynamics of proteins, the\nkinetics of chemical reactions or the stability of mechanical systems. In 1940\nKramers calculated escape rates both in the high damping and the low damping\nregime and suggested that the rate must have a maximum for intermediate\ndamping. This phenomenon, today known as the Kramers turnover, has triggered\nimportant theoretical and numerical studies. However, to date there is no\ndirect and quantitative experimental verification of this turnover. Using a\nnanoparticle trapped in a bi-stable optical potential we experimentally measure\nthe nanoparticle's transition rates for variable damping and directly resolve\nthe Kramers turnover. Our measurements are in agreement with an analytical\nmodel that is free of adjustable parameters.\n",
"title": "Direct Measurement of Kramers Turnover with a Levitated Nanoparticle"
}
| null | null | null | null | true | null |
9898
| null |
Default
| null | null |
null |
{
"abstract": " Sparse exchangeable graphs resolve some pathologies in traditional random\ngraph models, notably, providing models that are both projective and allow\nsparsity. In a recent paper, Caron and Rousseau (2017) show that for a large\nclass of sparse exchangeable models, the sparsity behaviour is governed by a\nsingle parameter: the tail-index of the function (the graphon) that\nparameterizes the model. We propose an estimator for this parameter and\nquantify its risk. Our estimator is a simple, explicit function of the degrees\nof the observed graph. In many situations of practical interest, the risk\ndecays polynomially in the size of the observed graph. Accordingly, the\nestimator is practically useful for estimation of sparse exchangeable models.\nWe also derive the analogous results for the bipartite sparse exchangeable\ncase.\n",
"title": "An estimator for the tail-index of graphex processes"
}
| null | null |
[
"Mathematics",
"Statistics"
] | null | true | null |
9899
| null |
Validated
| null | null |
null |
{
"abstract": " Tête-à-tête graphs and relative tête-à-tête graphs were\nintroduced by N. A'Campo in 2010 to model monodromies of isolated plane curves.\nBy recent workof Fdez de Bobadilla, Pe Pereira and the author, they provide a\nway of modeling the periodic mapping classes that leave some boundary component\ninvariant. In this work we introduce the notion of general tête-à-tête\ngraph and prove that they model all periodic mapping classes. We also describe\nalgorithms that take a Seifert manifold and a horizontal surface and return a\ntête-à-tête graph and vice versa.\n",
"title": "General tête-à-tête graphs and Seifert manifolds"
}
| null | null | null | null | true | null |
9900
| null |
Default
| null | null |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.