text
null | inputs
dict | prediction
null | prediction_agent
null | annotation
list | annotation_agent
null | multi_label
bool 1
class | explanation
null | id
stringlengths 1
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{
"abstract": " In this paper, we calculate the numbers of irreducible ordinary characters\nand irreducible Brauer characters in a block of a finite group $G$, whose\nassociated fusion system over a 2-subgroup $P$ of $G$ (which is a defect group\nof the block) has the hyperfocal subgroup $\\mathbb Z_{2^n}\\times \\mathbb\nZ_{2^n}$ for some $n\\geq 2$, when the block is controlled by the normalizer\n$N_G(P)$ and the hyperfocal subgroup is contained in the center of $P$, or when\nthe block is not controlled by $N_G(P)$ and the hyperfocal subgroup is\ncontained in the center of the unique essential subgroup in the fusion system.\nIn particular, Alperin's weight conjecture holds in the considered cases.\n",
"title": "Blocks with the hyperfocal subgroup $Z_{2^n}\\times Z_{2^n}$"
}
| null | null | null | null | true | null |
10601
| null |
Default
| null | null |
null |
{
"abstract": " This paper investigates asymptotic behaviors of gradient descent algorithms\n(particularly accelerated gradient descent and stochastic gradient descent) in\nthe context of stochastic optimization arose in statistics and machine learning\nwhere objective functions are estimated from available data. We show that these\nalgorithms can be modeled by continuous-time ordinary or stochastic\ndifferential equations, and their asymptotic dynamic evolutions and\ndistributions are governed by some linear ordinary or stochastic differential\nequations, as the data size goes to infinity. We illustrate that our study can\nprovide a novel unified framework for a joint computational and statistical\nasymptotic analysis on dynamic behaviors of these algorithms with the time (or\nthe number of iterations in the algorithms) and large sample behaviors of the\nstatistical decision rules (like estimators and classifiers) that the\nalgorithms are applied to compute, where the statistical decision rules are the\nlimits of the random sequences generated from these iterative algorithms as the\nnumber of iterations goes to infinity. The analysis results may shed light on\nthe empirically observed phenomenon of escaping from saddle points, avoiding\nbad local minimizers, and converging to good local minimizers, which depends on\nlocal geometry, learning rate and batch size, when stochastic gradient descent\nalgorithms are applied to solve non-convex optimization problems.\n",
"title": "Asymptotic Analysis via Stochastic Differential Equations of Gradient Descent Algorithms in Statistical and Computational Paradigms"
}
| null | null | null | null | true | null |
10602
| null |
Default
| null | null |
null |
{
"abstract": " The pigeonhole principle states that if n items are contained in m boxes,\nthen at least one box has no more than n/m items. It is utilized to solve many\ndata management problems, especially for thresholded similarity searches.\nDespite many pigeonhole principle-based solutions proposed in the last few\ndecades, the condition stated by the principle is weak. It only constrains the\nnumber of items in a single box. By organizing the boxes in a ring, we propose\na new principle, called the pigeonring principle, which constrains the number\nof items in multiple boxes and yields stronger conditions.\nTo utilize the new principle, we focus on problems defined in the form of\nidentifying data objects whose similarities or distances to the query is\nconstrained by a threshold. Many solutions to these problems utilize the\npigeonhole principle to find candidates that satisfy a filtering condition. By\nthe new principle, stronger filtering conditions can be established. We show\nthat the pigeonhole principle is a special case of the new principle. This\nsuggests that all the pigeonhole principle-based solutions are possible to be\naccelerated by the new principle. A universal filtering framework is introduced\nto encompass the solutions to these problems based on the new principle.\nBesides, we discuss how to quickly find candidates specified by the new\nprinciple. The implementation requires only minor modifications on top of\nexisting pigeonhole principle-based algorithms. Experimental results on real\ndatasets demonstrate the applicability of the new principle as well as the\nsuperior performance of the algorithms based on the new principle.\n",
"title": "Pigeonring: A Principle for Faster Thresholded Similarity Search"
}
| null | null | null | null | true | null |
10603
| null |
Default
| null | null |
null |
{
"abstract": " Anomaly matching constrains low-energy physics of strongly-coupled field\ntheories, but it is not useful at finite temperature due to contamination from\nhigh-energy states. The known exception is an 't Hooft anomaly involving\none-form symmetries as in pure $SU(N)$ Yang-Mills theory at $\\theta=\\pi$.\nRecent development about large-$N$ volume independence, however, gives us a\ncircumstantial evidence that 't Hooft anomalies can also remain under circle\ncompactifications in some theories without one-form symmetries. We develop a\nsystematic procedure for deriving an 't Hooft anomaly of the\ncircle-compactified theory starting from the anomaly of the original\nuncompactified theory without one-form symmetries, where the twisted boundary\ncondition for the compactified direction plays a pivotal role. As an\napplication, we consider $\\mathbb{Z}_N$-twisted $\\mathbb{C}P^{N-1}$ sigma model\nand massless $\\mathbb{Z}_N$-QCD, and compute their anomalies explicitly.\n",
"title": "Circle compactification and 't Hooft anomaly"
}
| null | null | null | null | true | null |
10604
| null |
Default
| null | null |
null |
{
"abstract": " A high-speed 100 MHz strain monitor using a fiber Bragg grating, an optical\nfilter, and a mode-locked optical fiber laser has been devised, which has a\nresolution of $\\Delta L/L\\sim10^{-4}$. The strain monitor is sufficiently fast\nand robust for the magnetostriction measurements of magnetic materials under\nultrahigh magnetic fields generated with destructive pulse magnets, where the\nsweep rate is in the range of 10-100 T/$\\mu$s. As a working example, the\nmagnetostriction of LaCoO$_{3}$ was measured at room temperature, 115 K, and\n7$\\sim$4.2 K up to a maximum magnetic field of 150 T. The smooth $B^{2}$\ndependence and the first-order transition were observed at 115 K and 7$\\sim$4.2\nK, respectively, reflecting the field-induced spin-state evolution.\n",
"title": "High-speed 100 MHz strain monitor using fiber Bragg grating and optical filter for magnetostriction measurements under ultrahigh magnetic fields"
}
| null | null |
[
"Physics"
] | null | true | null |
10605
| null |
Validated
| null | null |
null |
{
"abstract": " We present a functional form of the Erdös-Renyi law of large numbers for\nLevy processes.\n",
"title": "Functional limit laws for the increments of Lévy processes"
}
| null | null | null | null | true | null |
10606
| null |
Default
| null | null |
null |
{
"abstract": " We present a memristive device based R$ ^3 $PUF construction achieving highly\ndesired PUF properties, which are not offered by most current PUF designs: (1)\nHigh reliability, almost 100\\% that is crucial for PUF-based cryptographic key\ngenerations, significantly reducing, or even eliminating the expensive overhead\nof on-chip error correction logic and the associated helper on-chip data\nstorage or off-chip storage and transfer. (2) Reconfigurability, while current\nPUF designs rarely exhibit such an attractive property. We validate our R$ ^3\n$PUF via extensive Monte-Carlo simulations in Cadence based on parameters of\nreal devices. The R$ ^3 $PUF is simple, cost-effective and easy to manage\ncompared to other PUF constructions exhibiting high reliability or\nreconfigurability. None of previous PUF constructions is able to provide both\ndesired high reliability and reconfigurability concurrently.\n",
"title": "R$^3$PUF: A Highly Reliable Memristive Device based Reconfigurable PUF"
}
| null | null |
[
"Computer Science"
] | null | true | null |
10607
| null |
Validated
| null | null |
null |
{
"abstract": " In this paper, we demonstrate the application of Fuzzy Markup Language (FML)\nto construct an FML-based Dynamic Assessment Agent (FDAA), and we present an\nFML-based Human-Machine Cooperative System (FHMCS) for the game of Go. The\nproposed FDAA comprises an intelligent decision-making and learning mechanism,\nan intelligent game bot, a proximal development agent, and an intelligent\nagent. The intelligent game bot is based on the open-source code of Facebook\nDarkforest, and it features a representational state transfer application\nprogramming interface mechanism. The proximal development agent contains a\ndynamic assessment mechanism, a GoSocket mechanism, and an FML engine with a\nfuzzy knowledge base and rule base. The intelligent agent contains a GoSocket\nengine and a summarization agent that is based on the estimated win rate,\nreal-time simulation number, and matching degree of predicted moves.\nAdditionally, the FML for player performance evaluation and linguistic\ndescriptions for game results commentary are presented. We experimentally\nverify and validate the performance of the FDAA and variants of the FHMCS by\ntesting five games in 2016 and 60 games of Google Master Go, a new version of\nthe AlphaGo program, in January 2017. The experimental results demonstrate that\nthe proposed FDAA can work effectively for Go applications.\n",
"title": "FML-based Dynamic Assessment Agent for Human-Machine Cooperative System on Game of Go"
}
| null | null |
[
"Computer Science"
] | null | true | null |
10608
| null |
Validated
| null | null |
null |
{
"abstract": " We present ALMA detections of the [CI] 1-0, CO J=3-2, and CO J=4-3 emission\nlines, as well as the ALMA band 4 continuum for a compact star-forming galaxy\n(cSFG) at z=2.225, 3D-HST GS30274. As is typical for cSFGs, this galaxy has a\nstellar mass of $1.89 \\pm 0.47\\,\\times 10^{11}\\,\\rm{M}_\\odot$, with a star\nformation rate of $214\\pm44\\,\\rm{M}_\\odot\\,\\rm{yr}^{-1}$ putting it on the\nstar-forming `main-sequence', but with an H-band effective radius of 2.5 kpc,\nmaking it much smaller than the bulk of `main-sequence' star-forming galaxies.\nThe intensity ratio of the line detections yield an ISM density (~ 6 $\\times\n10^{4}\\,\\rm{cm}^{-3}$) and a UV-radiation field ( ~2 $\\times 10^4\\,\\rm{G}_0$),\nsimilar to the values in local starburst and ultra-luminous infrared galaxy\nenvironments. A starburst phase is consistent with the short depletion times\n($t_{\\rm H2, dep} \\leq 140$ Myr) we find using three different proxies for the\nH2 mass ([CI], CO, dust mass). This depletion time is significantly shorter\nthan in more extended SFGs with similar stellar masses and SFRs. Moreover, the\ngas fraction of 3D-HST GS30274 is smaller than typically found in extended\ngalaxies. We measure the CO and [CI] kinematics and find a FWHM line width of\n~$750 \\pm 41 $ km s$^{-1}$. The CO and [CI] FWHM are consistent with a\npreviously measured H$\\alpha$ FWHM for this source. The line widths are\nconsistent with gravitational motions, suggesting we are seeing a compact\nmolecular gas reservoir. A previous merger event, as suggested by the\nasymmetric light profile, may be responsible for the compact distribution of\ngas and has triggered a central starburst event. This event gives rise to the\nstarburst-like ISM properties and short depletion times. The centrally located\nand efficient star formation is quickly building up a dense core of stars,\nresponsible for the compact distribution of stellar light in 3D-HST GS30274.\n",
"title": "ALMA reveals starburst-like interstellar medium conditions in a compact star-forming galaxy at z ~ 2 using [CI] and CO"
}
| null | null |
[
"Physics"
] | null | true | null |
10609
| null |
Validated
| null | null |
null |
{
"abstract": " Finding central nodes is a fundamental problem in network analysis.\nBetweenness centrality is a well-known measure which quantifies the importance\nof a node based on the fraction of shortest paths going though it. Due to the\ndynamic nature of many today's networks, algorithms that quickly update\ncentrality scores have become a necessity. For betweenness, several dynamic\nalgorithms have been proposed over the years, targeting different update types\n(incremental- and decremental-only, fully-dynamic). In this paper we introduce\na new dynamic algorithm for updating betweenness centrality after an edge\ninsertion or an edge weight decrease. Our method is a combination of two\nindependent contributions: a faster algorithm for updating pairwise distances\nas well as number of shortest paths, and a faster algorithm for updating\ndependencies. Whereas the worst-case running time of our algorithm is the same\nas recomputation, our techniques considerably reduce the number of operations\nperformed by existing dynamic betweenness algorithms.\n",
"title": "Faster Betweenness Centrality Updates in Evolving Networks"
}
| null | null |
[
"Computer Science"
] | null | true | null |
10610
| null |
Validated
| null | null |
null |
{
"abstract": " The latest measurements of CMB electron scattering optical depth reported by\nPlanck significantly reduces the allowed space of HI reionization models,\npointing towards a later ending and/or less extended phase transition than\npreviously believed. Reionization impulsively heats the intergalactic medium\n(IGM) to $\\sim10^4$ K, and owing to long cooling and dynamical times in the\ndiffuse gas, comparable to the Hubble time, memory of reionization heating is\nretained. Therefore, a late ending reionization has significant implications\nfor the structure of the $z\\sim5-6$ Lyman-$\\alpha$ (ly$\\alpha$) forest. Using\nstate-of-the-art hydrodynamical simulations that allow us to vary the timing of\nreionization and its associated heat injection, we argue that extant thermal\nsignatures from reionization can be detected via the ly$\\alpha$ forest power\nspectrum at $5< z<6$. This arises because the small-scale cutoff in the power\ndepends not only the the IGMs temperature at these epochs, but is also\nparticularly sensitive to the pressure smoothing scale set by the IGMs full\nthermal history. Comparing our different reionization models with existing\nmeasurements of the ly$\\alpha$ forest flux power spectrum at $z=5.0-5.4$, we\nfind that models satisfying Planck's $\\tau_e$ constraint, favor a moderate\namount of heat injection consistent with galaxies driving reionization, but\ndisfavoring quasar driven scenarios. We explore the impact of different\nreionization histories and heating models on the shape of the power spectrum,\nand find that they can produce similar effects, but argue that this degeneracy\ncan be broken with high enough quality data. We study the feasibility of\nmeasuring the flux power spectrum at $z\\simeq 6$ using mock quasar spectra and\nconclude that a sample of $\\sim10$ high-resolution spectra with attainable S/N\nratio will allow to discriminate between different reionization scenarios.\n",
"title": "Constraining Reionization with the $z \\sim 5-6$ Lyman-$α$ Forest Power Spectrum: the Outlook after Planck"
}
| null | null | null | null | true | null |
10611
| null |
Default
| null | null |
null |
{
"abstract": " Reinforcement learning (RL) makes it possible to train agents capable of\nachiev- ing sophisticated goals in complex and uncertain environments. A key\ndifficulty in reinforcement learning is specifying a reward function for the\nagent to optimize. Traditionally, imitation learning in RL has been used to\novercome this problem. Unfortunately, hitherto imitation learning methods tend\nto require that demonstra- tions are supplied in the first-person: the agent is\nprovided with a sequence of states and a specification of the actions that it\nshould have taken. While powerful, this kind of imitation learning is limited\nby the relatively hard problem of collect- ing first-person demonstrations.\nHumans address this problem by learning from third-person demonstrations: they\nobserve other humans perform tasks, infer the task, and accomplish the same\ntask themselves.\nIn this paper, we present a method for unsupervised third-person imitation\nlearn- ing. Here third-person refers to training an agent to correctly achieve\na simple goal in a simple environment when it is provided a demonstration of a\nteacher achieving the same goal but from a different viewpoint; and\nunsupervised refers to the fact that the agent receives only these third-person\ndemonstrations, and is not provided a correspondence between teacher states and\nstudent states. Our methods primary insight is that recent advances from domain\nconfusion can be utilized to yield domain agnostic features which are crucial\nduring the training process. To validate our approach, we report successful\nexperiments on learning from third-person demonstrations in a pointmass domain,\na reacher domain, and inverted pendulum.\n",
"title": "Third-Person Imitation Learning"
}
| null | null | null | null | true | null |
10612
| null |
Default
| null | null |
null |
{
"abstract": " Drafting strong players is crucial for the team success. We describe a new\ndata-driven interpretable approach for assessing draft prospects in the\nNational Hockey League. Successful previous approaches have built a predictive\nmodel based on player features, or derived performance predictions from the\nobserved performance of comparable players in a cohort. This paper develops\nmodel tree learning, which incorporates strengths of both model-based and\ncohort-based approaches. A model tree partitions the feature space according to\nthe values of discrete features, or learned thresholds for continuous features.\nEach leaf node in the tree defines a group of players, easily described to\nhockey experts, with its own group regression model. Compared to a single\nmodel, the model tree forms an ensemble that increases predictive power.\nCompared to cohort-based approaches, the groups of comparables are discovered\nfrom the data, without requiring a similarity metric. The performance\npredictions of the model tree are competitive with the state-of-the-art\nmethods, which validates our model empirically. We show in case studies that\nthe model tree player ranking can be used to highlight strong and weak points\nof players.\n",
"title": "Model Trees for Identifying Exceptional Players in the NHL Draft"
}
| null | null |
[
"Computer Science"
] | null | true | null |
10613
| null |
Validated
| null | null |
null |
{
"abstract": " The distributions of dark matter and baryons in the Universe are known to be\nvery different: the dark matter resides in extended halos, while a significant\nfraction of the baryons have radiated away much of their initial energy and\nfallen deep into the potential wells. This difference in morphology leads to\nthe widely held conclusion that dark matter cannot cool and collapse on any\nscale. We revisit this assumption, and show that a simple model where dark\nmatter is charged under a \"dark electromagnetism\" can allow dark matter to form\ngravitationally collapsed objects with characteristic mass scales much smaller\nthan that of a Milky Way-type galaxy. Though the majority of the dark matter in\nspiral galaxies would remain in the halo, such a model opens the possibility\nthat galaxies and their associated dark matter play host to a significant\nnumber of collapsed substructures. The observational signatures of such\nstructures are not well explored, but potentially interesting.\n",
"title": "Collapsed Dark Matter Structures"
}
| null | null | null | null | true | null |
10614
| null |
Default
| null | null |
null |
{
"abstract": " Let $(G,\\alpha)$ and $(H,\\beta)$ be locally compact Hausdorff groupoids with\nHaar systems, and let $(X,\\lambda)$ be a topological correspondence from\n$(G,\\alpha)$ to $(H,\\beta)$ which induce the ${C}^*$-correspondence\n$\\mathcal{H}(X)\\colon {C}^*(G,\\alpha)\\to {C}^*(H,\\beta)$. We give sufficient\ntopological conditions which when satisfied the ${C}^*$-correspondence\n$\\mathcal{H}(X)$ is proper, that is, the ${C}^*$-algebra ${C}^*(G,\\alpha)$ acts\non the Hilbert ${C}^*(H,\\beta)$-module ${H}(X)$ via the comapct operators. Thus\na proper topological correspondence produces an element in\n${KK}({C}^*(G,\\alpha),{C}^*(H,\\beta))$.\n",
"title": "Locally free actions of groupoids and proper topological correspondences"
}
| null | null | null | null | true | null |
10615
| null |
Default
| null | null |
null |
{
"abstract": " A key part of implementing high-level languages is providing built-in and\ndefault data structures. Yet selecting good defaults is hard. A mutable data\nstructure's workload is not known in advance, and it may shift over its\nlifetime - e.g., between read-heavy and write-heavy, or from heavy contention\nby multiple threads to single-threaded or low-frequency use. One idea is to\nswitch implementations adaptively, but it is nontrivial to switch the\nimplementation of a concurrent data structure at runtime. Performing the\ntransition requires a concurrent snapshot of data structure contents, which\nnormally demands special engineering in the data structure's design. However,\nin this paper we identify and formalize an relevant property of lock-free\nalgorithms. Namely, lock-freedom is sufficient to guarantee that freezing\nmemory locations in an arbitrary order will result in a valid snapshot. Several\nfunctional languages have data structures that freeze and thaw, transitioning\nbetween mutable and immutable, such as Haskell vectors and Clojure transients,\nbut these enable only single-threaded writers. We generalize this approach to\naugment an arbitrary lock-free data structure with the ability to gradually\nfreeze and optionally transition to a new representation. This augmentation\ndoesn't require changing the algorithm or code for the data structure, only\nreplacing its datatype for mutable references with a freezable variant. In this\npaper, we present an algorithm for lifting plain to adaptive data and prove\nthat the resulting hybrid data structure is itself lock-free, linearizable, and\nsimulates the original. We also perform an empirical case study in the context\nof heating up and cooling down concurrent maps.\n",
"title": "Adaptive Lock-Free Data Structures in Haskell: A General Method for Concurrent Implementation Swapping"
}
| null | null | null | null | true | null |
10616
| null |
Default
| null | null |
null |
{
"abstract": " This paper develops systematically the output feedback exponential\nstabilization for a one-dimensional unstable/anti-stable wave equation where\nthe control boundary suffers from both internal nonlinear uncertainty and\nexternal disturbance. Using only two displacement signals, we propose a\ndisturbance estimator that not only can estimate successfully the disturbance\nin the sense that the error is in $L^2(0,\\infty)$ but also is free high-gain.\nWith the estimated disturbance, we design a state observer that is\nexponentially convergent to the state of original system. An observer-based\noutput feedback stabilizing control law is proposed. The disturbance is then\ncanceled in the feedback loop by its approximated value. The closed-loop system\nis shown to be exponentially stable and it can be guaranteed that all internal\nsignals are uniformly bounded.\n",
"title": "Output feedback exponential stabilization of a nonlinear 1-D wave equation with boundary input"
}
| null | null | null | null | true | null |
10617
| null |
Default
| null | null |
null |
{
"abstract": " One of the essential prerequisites for detection of Earth-like extra-solar\nplanets or direct measurements of the cosmological expansion is the accurate\nand precise wavelength calibration of astronomical spectrometers. It has\nalready been realized that the large number of exactly known optical\nfrequencies provided by laser frequency combs ('astrocombs') can significantly\nsurpass conventionally used hollow-cathode lamps as calibration light sources.\nA remaining challenge, however, is generation of frequency combs with lines\nresolvable by astronomical spectrometers. Here we demonstrate an astrocomb\ngenerated via soliton formation in an on-chip microphotonic resonator\n('microresonator') with a resolvable line spacing of 23.7 GHz. This comb is\nproviding wavelength calibration on the 10 cm/s radial velocity level on the\nGIANO-B high-resolution near-infrared spectrometer. As such, microresonator\nfrequency combs have the potential of providing broadband wavelength\ncalibration for the next-generation of astronomical instruments in\nplanet-hunting and cosmological research.\n",
"title": "A Microphotonic Astrocomb"
}
| null | null | null | null | true | null |
10618
| null |
Default
| null | null |
null |
{
"abstract": " For the past 5 years, the ILSVRC competition and the ImageNet dataset have\nattracted a lot of interest from the Computer Vision community, allowing for\nstate-of-the-art accuracy to grow tremendously. This should be credited to the\nuse of deep artificial neural network designs. As these became more complex,\nthe storage, bandwidth, and compute requirements increased. This means that\nwith a non-distributed approach, even when using the most high-density server\navailable, the training process may take weeks, making it prohibitive.\nFurthermore, as datasets grow, the representation learning potential of deep\nnetworks grows as well by using more complex models. This synchronicity\ntriggers a sharp increase in the computational requirements and motivates us to\nexplore the scaling behaviour on petaflop scale supercomputers. In this paper\nwe will describe the challenges and novel solutions needed in order to train\nResNet-50 in this large scale environment. We demonstrate above 90\\% scaling\nefficiency and a training time of 28 minutes using up to 104K x86 cores. This\nis supported by software tools from Intel's ecosystem. Moreover, we show that\nwith regular 90 - 120 epoch train runs we can achieve a top-1 accuracy as high\nas 77\\% for the unmodified ResNet-50 topology. We also introduce the novel\nCollapsed Ensemble (CE) technique that allows us to obtain a 77.5\\% top-1\naccuracy, similar to that of a ResNet-152, while training a unmodified\nResNet-50 topology for the same fixed training budget. All ResNet-50 models as\nwell as the scripts needed to replicate them will be posted shortly.\n",
"title": "Scale out for large minibatch SGD: Residual network training on ImageNet-1K with improved accuracy and reduced time to train"
}
| null | null | null | null | true | null |
10619
| null |
Default
| null | null |
null |
{
"abstract": " Suffix trees have recently become very successful data structures in handling\nlarge data sequences such as DNA or Protein sequences. Consequently parallel\narchitectures have become ubiquitous. We present a novel alphabet-dependent\nparallel algorithm which attempts to take advantage of the perverseness of the\nmulticore architecture. Microsatellites are important for their biological\nrelevance hence our algorithm is based on time efficient construction for\nidentification of such. We experimentally achieved up to 15x speedup over the\nsequential algorithm on different input sizes of biological sequences.\n",
"title": "Alphabet-dependent Parallel Algorithm for Suffix Tree Construction for Pattern Searching"
}
| null | null | null | null | true | null |
10620
| null |
Default
| null | null |
null |
{
"abstract": " Understanding the interaction between the valves and walls of the heart is\nimportant in assessing and subsequently treating heart dysfunction. With\nadvancements in cardiac imaging, nonlinear mechanics and computational\ntechniques, it is now possible to explore the mechanics of valve-heart\ninteractions using anatomically and physiologically realistic models. This\nstudy presents an integrated model of the mitral valve (MV) coupled to the left\nventricle (LV), with the geometry derived from in vivo clinical magnetic\nresonance images. Numerical simulations using this coupled MV-LV model are\ndeveloped using an immersed boundary/finite element method. The model\nincorporates detailed valvular features, left ventricular contraction,\nnonlinear soft tissue mechanics, and fluid-mediated interactions between the MV\nand LV wall. We use the model to simulate the cardiac function from diastole to\nsystole, and investigate how myocardial active relaxation function affects the\nLV pump function. The results of the new model agree with in vivo measurements,\nand demonstrate that the diastolic filling pressure increases significantly\nwith impaired myocardial active relaxation to maintain the normal cardiac\noutput. The coupled model has the potential to advance fundamental knowledge of\nmechanisms underlying MV-LV interaction, and help in risk stratification and\noptimization of therapies for heart diseases.\n",
"title": "A coupled mitral valve -- left ventricle model with fluid-structure interaction"
}
| null | null |
[
"Computer Science",
"Physics"
] | null | true | null |
10621
| null |
Validated
| null | null |
null |
{
"abstract": " Optimal estimation of signal amplitude, background level, and photocentre\nlocation is crucial to the combined extraction of astrometric and photometric\ninformation from focal plane images, and in particular from the one-dimensional\nmeasurements performed by Gaia on intermediate to faint magnitude stars. Our\ngoal is to define a convenient maximum likelihood framework, suited to\nefficient iterative implementation and to assessment of noise level, bias, and\ncorrelation among variables. The analytical model is investigated numerically\nand verified by simulation over a range of magnitude and background values. The\nestimates are unbiased, with a well-understood correlation between amplitude\nand background, and with a much lower correlation of either of them with\nlocation, further alleviated in case of signal symmetry. Two versions of the\nalgorithm are implemented and tested against each other, respectively, for\nindependent and combined parameter estimation. Both are effective and provide\nconsistent results, but the latter is more efficient because it takes into\naccount the flux-background estimate correlation.\n",
"title": "Performance of an Algorithm for Estimation of Flux, Background and Location on One-Dimensional Signals"
}
| null | null | null | null | true | null |
10622
| null |
Default
| null | null |
null |
{
"abstract": " In deep learning, \\textit{depth}, as well as \\textit{nonlinearity}, create\nnon-convex loss surfaces. Then, does depth alone create bad local minima? In\nthis paper, we prove that without nonlinearity, depth alone does not create bad\nlocal minima, although it induces non-convex loss surface. Using this insight,\nwe greatly simplify a recently proposed proof to show that all of the local\nminima of feedforward deep linear neural networks are global minima. Our\ntheoretical results generalize previous results with fewer assumptions, and\nthis analysis provides a method to show similar results beyond square loss in\ndeep linear models.\n",
"title": "Depth Creates No Bad Local Minima"
}
| null | null | null | null | true | null |
10623
| null |
Default
| null | null |
null |
{
"abstract": " We define a quantity $c_m(n,k)$ as a generalization of the notion of the\ncomposition of the positive integer $n$ into $k$ parts. We proceed to derive\nsome known properties of this quantity. In particular, we relate two partial\nBell polynomials, in which the sequence of the variables of one polynomial is\nthe invert transform of the sequence of the variables of the other. We connect\nthe quantities $c_m(n,k)$ and $c_{m-1}(n,k)$ via Pascal matrices. We then\nrelate $c_m(n,k)$ with the numbers of some restricted words over a finite\nalphabet. We develop a method which transfers some properties of restricted\nwords over an alphabet of $N$ letters to the restricted words over an alphabet\nof $N+1$ letters. Several examples illustrate our findings. Note that all our\nresults depend solely on the initial arithmetic function $f_0$.\n",
"title": "Some Formulas for Numbers of Restricted Words"
}
| null | null |
[
"Mathematics"
] | null | true | null |
10624
| null |
Validated
| null | null |
null |
{
"abstract": " In recent years, bullying and aggression against users on social media have\ngrown significantly, causing serious consequences to victims of all\ndemographics. In particular, cyberbullying affects more than half of young\nsocial media users worldwide, and has also led to teenage suicides, prompted by\nprolonged and/or coordinated digital harassment. Nonetheless, tools and\ntechnologies for understanding and mitigating it are scarce and mostly\nineffective. In this paper, we present a principled and scalable approach to\ndetect bullying and aggressive behavior on Twitter. We propose a robust\nmethodology for extracting text, user, and network-based attributes, studying\nthe properties of cyberbullies and aggressors, and what features distinguish\nthem from regular users. We find that bully users post less, participate in\nfewer online communities, and are less popular than normal users, while\naggressors are quite popular and tend to include more negativity in their\nposts. We evaluate our methodology using a corpus of 1.6M tweets posted over 3\nmonths, and show that machine learning classification algorithms can accurately\ndetect users exhibiting bullying and aggressive behavior, achieving over 90%\nAUC.\n",
"title": "Mean Birds: Detecting Aggression and Bullying on Twitter"
}
| null | null | null | null | true | null |
10625
| null |
Default
| null | null |
null |
{
"abstract": " Robots are typically not created with security as a main concern. Contrasting\nto typical IT systems, cyberphysical systems rely on security to handle safety\naspects. In light of the former, classic scoring methods such as the Common\nVulnerability Scoring System (CVSS) are not able to accurately capture the\nseverity of robot vulnerabilities. The present research work focuses upon\ncreating an open and free to access Robot Vulnerability Scoring System (RVSS)\nthat considers major relevant issues in robotics including a) robot safety\naspects, b) assessment of downstream implications of a given vulnerability, c)\nlibrary and third-party scoring assessments and d) environmental variables,\nsuch as time since vulnerability disclosure or exposure on the web. Finally, an\nexperimental evaluation of RVSS with contrast to CVSS is provided and discussed\nwith focus on the robotics security landscape.\n",
"title": "Towards an open standard for assessing the severity of robot security vulnerabilities, the Robot Vulnerability Scoring System (RVSS)"
}
| null | null | null | null | true | null |
10626
| null |
Default
| null | null |
null |
{
"abstract": " This paper considers a general data-fitting problem over a networked system,\nin which many computing nodes are connected by an undirected graph. This kind\nof problem can find many real-world applications and has been studied\nextensively in the literature. However, existing solutions either need a\ncentral controller for information sharing or requires slot synchronization\namong different nodes, which increases the difficulty of practical\nimplementations, especially for a very large and heterogeneous system.\nAs a contrast, in this paper, we treat the data-fitting problem over the\nnetwork as a stochastic programming problem with many constraints. By adapting\nthe results in a recent paper, we design a fully distributed and asynchronized\nstochastic gradient descent (SGD) algorithm. We show that our algorithm can\nachieve global optimality and consensus asymptotically by only local\ncomputations and communications. Additionally, we provide a sharp lower bound\nfor the convergence speed in the regular graph case. This result fits the\nintuition and provides guidance to design a `good' network topology to speed up\nthe convergence. Also, the merit of our design is validated by experiments on\nboth synthetic and real-world datasets.\n",
"title": "Fully Distributed and Asynchronized Stochastic Gradient Descent for Networked Systems"
}
| null | null | null | null | true | null |
10627
| null |
Default
| null | null |
null |
{
"abstract": " We develop differentially private hypothesis testing methods for the small\nsample regime. Given a sample $\\cal D$ from a categorical distribution $p$ over\nsome domain $\\Sigma$, an explicitly described distribution $q$ over $\\Sigma$,\nsome privacy parameter $\\varepsilon$, accuracy parameter $\\alpha$, and\nrequirements $\\beta_{\\rm I}$ and $\\beta_{\\rm II}$ for the type I and type II\nerrors of our test, the goal is to distinguish between $p=q$ and\n$d_{\\rm{TV}}(p,q) \\geq \\alpha$.\nWe provide theoretical bounds for the sample size $|{\\cal D}|$ so that our\nmethod both satisfies $(\\varepsilon,0)$-differential privacy, and guarantees\n$\\beta_{\\rm I}$ and $\\beta_{\\rm II}$ type I and type II errors. We show that\ndifferential privacy may come for free in some regimes of parameters, and we\nalways beat the sample complexity resulting from running the $\\chi^2$-test with\nnoisy counts, or standard approaches such as repetition for endowing\nnon-private $\\chi^2$-style statistics with differential privacy guarantees. We\nexperimentally compare the sample complexity of our method to that of recently\nproposed methods for private hypothesis testing.\n",
"title": "Priv'IT: Private and Sample Efficient Identity Testing"
}
| null | null |
[
"Computer Science",
"Mathematics",
"Statistics"
] | null | true | null |
10628
| null |
Validated
| null | null |
null |
{
"abstract": " Remote sensing of the atmospheres of distant worlds motivates a firm\nunderstanding of radiative transfer. In this review, we provide a pedagogical\ncookbook that describes the principal ingredients needed to perform a radiative\ntransfer calculation and predict the spectrum of an exoplanet atmosphere,\nincluding solving the radiative transfer equation, calculating opacities (and\nchemistry), iterating for radiative equilibrium (or not), and adapting the\noutput of the calculations to the astronomical observations. A review of the\nstate of the art is performed, focusing on selected milestone papers.\nOutstanding issues, including the need to understand aerosols or clouds and\nelucidating the assumptions and caveats behind inversion methods, are\ndiscussed. A checklist is provided to assist referees/reviewers in their\nscrutiny of works involving radiative transfer. A table summarizing the\nmethodology employed by past studies is provided.\n",
"title": "Radiative Transfer for Exoplanet Atmospheres"
}
| null | null | null | null | true | null |
10629
| null |
Default
| null | null |
null |
{
"abstract": " We provide, to the best of our knowledge, the first computational study of\nextensive-form adversarial team games. These games are sequential, zero-sum\ngames in which a team of players, sharing the same utility function, faces an\nadversary. We define three different scenarios according to the communication\ncapabilities of the team. In the first, the teammates can communicate and\ncorrelate their actions both before and during the play. In the second, they\ncan only communicate before the play. In the third, no communication is\npossible at all. We define the most suitable solution concepts, and we study\nthe inefficiency caused by partial or null communication, showing that the\ninefficiency can be arbitrarily large in the size of the game tree.\nFurthermore, we study the computational complexity of the equilibrium-finding\nproblem in the three scenarios mentioned above, and we provide, for each of the\nthree scenarios, an exact algorithm. Finally, we empirically evaluate the\nscalability of the algorithms in random games and the inefficiency caused by\npartial or null communication.\n",
"title": "Computational Results for Extensive-Form Adversarial Team Games"
}
| null | null | null | null | true | null |
10630
| null |
Default
| null | null |
null |
{
"abstract": " When designing control strategies for differential-drive mobile robots, one\nstandard tool is the consideration of a point at a fixed distance along a line\northogonal to the wheel axis instead of the full pose of the vehicle. This\nabstraction supports replacing the non-holonomic, three-state unicycle model\nwith a much simpler two-state single-integrator model (i.e., a\nvelocity-controlled point). Yet this transformation comes at a performance\ncost, through the robot's precision and maneuverability. This work contains\nderivations for expressions of these precision and maneuverability costs in\nterms of the transformation's parameters. Furthermore, these costs show that\nonly selecting the parameter once over the course of an application may cause\nan undue loss of precision. Model Predictive Control (MPC) represents one such\nmethod to ameliorate this condition. However, MPC typically realizes a control\nsignal, rather than a parameter, so this work also proposes a Parametric Model\nPredictive Control (PMPC) method for parameter and sampling horizon\noptimization. Experimental results are presented that demonstrate the effects\nof the parameterization on the deployment of algorithms developed for the\nsingle-integrator model on actual differential-drive mobile robots.\n",
"title": "A Parametric MPC Approach to Balancing the Cost of Abstraction for Differential-Drive Mobile Robots"
}
| null | null | null | null | true | null |
10631
| null |
Default
| null | null |
null |
{
"abstract": " Although various norms for reciprocity-based cooperation have been suggested\nthat are evolutionarily stable against invasion from free riders, the process\nof alternation of norms and the role of diversified norms remain unclear in the\nevolution of cooperation. We clarify the co-evolutionary dynamics of norms and\ncooperation in indirect reciprocity and also identify the indispensable norms\nfor the evolution of cooperation. Inspired by the gene knockout method, a\ngenetic engineering technique, we developed the norm knockout method and\nclarified the norms necessary for the establishment of cooperation. The results\nof numerical investigations revealed that the majority of norms gradually\ntransitioned to tolerant norms after defectors are eliminated by strict norms.\nFurthermore, no cooperation emerges when specific norms that are intolerant to\ndefectors are knocked out.\n",
"title": "A norm knockout method on indirect reciprocity to reveal indispensable norms"
}
| null | null |
[
"Computer Science",
"Physics"
] | null | true | null |
10632
| null |
Validated
| null | null |
null |
{
"abstract": " In the online multiple testing problem, p-values corresponding to different\nnull hypotheses are observed one by one, and the decision of whether or not to\nreject the current hypothesis must be made immediately, after which the next\np-value is observed. Alpha-investing algorithms to control the false discovery\nrate (FDR), formulated by Foster and Stine, have been generalized and applied\nto many settings, including quality-preserving databases in science and\nmultiple A/B or multi-armed bandit tests for internet commerce. This paper\nimproves the class of generalized alpha-investing algorithms (GAI) in four\nways: (a) we show how to uniformly improve the power of the entire class of\nmonotone GAI procedures by awarding more alpha-wealth for each rejection,\ngiving a win-win resolution to a recent dilemma raised by Javanmard and\nMontanari, (b) we demonstrate how to incorporate prior weights to indicate\ndomain knowledge of which hypotheses are likely to be non-null, (c) we allow\nfor differing penalties for false discoveries to indicate that some hypotheses\nmay be more important than others, (d) we define a new quantity called the\ndecaying memory false discovery rate (mem-FDR) that may be more meaningful for\ntruly temporal applications, and which alleviates problems that we describe and\nrefer to as \"piggybacking\" and \"alpha-death\". Our GAI++ algorithms incorporate\nall four generalizations simultaneously, and reduce to more powerful variants\nof earlier algorithms when the weights and decay are all set to unity. Finally,\nwe also describe a simple method to derive new online FDR rules based on an\nestimated false discovery proportion.\n",
"title": "Online control of the false discovery rate with decaying memory"
}
| null | null | null | null | true | null |
10633
| null |
Default
| null | null |
null |
{
"abstract": " Most of the current game-theoretic demand-side management methods focus\nprimarily on the scheduling of home appliances, and the related numerical\nexperiments are analyzed under various scenarios to achieve the corresponding\nNash-equilibrium (NE) and optimal results. However, not much work is conducted\nfor academic or commercial buildings. The methods for optimizing\nacademic-buildings are distinct from the optimal methods for home appliances.\nIn my study, we address a novel methodology to control the operation of\nheating, ventilation, and air conditioning system (HVAC). With the development\nof Artificial Intelligence and computer technologies, reinforcement learning\n(RL) can be implemented in multiple realistic scenarios and help people to\nsolve thousands of real-world problems. Reinforcement Learning, which is\nconsidered as the art of future AI, builds the bridge between agents and\nenvironments through Markov Decision Chain or Neural Network and has seldom\nbeen used in power system. The art of RL is that once the simulator for a\nspecific environment is built, the algorithm can keep learning from the\nenvironment. Therefore, RL is capable of dealing with constantly changing\nsimulator inputs such as power demand, the condition of power system and\noutdoor temperature, etc. Compared with the existing distribution power system\nplanning mechanisms and the related game theoretical methodologies, our\nproposed algorithm can plan and optimize the hourly energy usage, and have the\nability to corporate with even shorter time window if needed.\n",
"title": "Multi-agent Reinforcement Learning Embedded Game for the Optimization of Building Energy Control and Power System Planning"
}
| null | null | null | null | true | null |
10634
| null |
Default
| null | null |
null |
{
"abstract": " We give the first example of a locally quasi-convex (even countable reflexive\nand $k_\\omega$) abelian group $G$ which does not admit the strongest compatible\nlocally quasi-convex group topology. Our group $G$ is the Graev free abelian\ngroup $A_G(\\mathbf{s})$ over a convergent sequence $\\mathbf{s}$.\n",
"title": "A locally quasi-convex abelian group without Mackey topology"
}
| null | null | null | null | true | null |
10635
| null |
Default
| null | null |
null |
{
"abstract": " Dipole moments are a simple, global measure of the accuracy of the electron\ndensity of a polar molecule. Dipole moments also affect the interactions of a\nmolecule with other molecules as well as electric fields. To directly assess\nthe accuracy of modern density functionals for calculating dipole moments, we\nhave developed a database of 200 benchmark dipole moments, using coupled\ncluster theory through triple excitations, extrapolated to the complete basis\nset limit. This new database is used to assess the performance of 88 popular or\nrecently developed density functionals. The results suggest that double hybrid\nfunctionals perform the best, yielding dipole moments within about 3.6-4.5%\nregularized RMS error versus the reference values---which is not very different\nfrom the 4% regularized RMS error produced by coupled cluster singles and\ndoubles. Many hybrid functionals also perform quite well, generating\nregularized RMS errors in the 5-6% range. Some functionals however exhibit\nlarge outliers and local functionals in general perform less well than hybrids\nor double hybrids.\n",
"title": "How accurate is density functional theory at predicting dipole moments? An assessment using a new database of 200 benchmark values"
}
| null | null | null | null | true | null |
10636
| null |
Default
| null | null |
null |
{
"abstract": " This paper explores an interesting new dimension to the challenging problem\nof predicting long-term scientific impact (LTSI) usually measured by the number\nof citations accumulated by a paper in the long-term. It is well known that\nearly citations (within 1-2 years after publication) acquired by a paper\npositively affects its LTSI. However, there is no work that investigates if the\nset of authors who bring in these early citations to a paper also affect its\nLTSI. In this paper, we demonstrate for the first time, the impact of these\nauthors whom we call early citers (EC) on the LTSI of a paper. Note that this\nstudy of the complex dynamics of EC introduces a brand new paradigm in citation\nbehavior analysis. Using a massive computer science bibliographic dataset we\nidentify two distinct categories of EC - we call those authors who have high\noverall publication/citation count in the dataset as influential and the rest\nof the authors as non-influential. We investigate three characteristic\nproperties of EC and present an extensive analysis of how each category\ncorrelates with LTSI in terms of these properties. In contrast to popular\nperception, we find that influential EC negatively affects LTSI possibly owing\nto attention stealing. To motivate this, we present several representative\nexamples from the dataset. A closer inspection of the collaboration network\nreveals that this stealing effect is more profound if an EC is nearer to the\nauthors of the paper being investigated. As an intuitive use case, we show that\nincorporating EC properties in the state-of-the-art supervised citation\nprediction models leads to high performance margins. At the closing, we present\nan online portal to visualize EC statistics along with the prediction results\nfor a given query paper.\n",
"title": "Understanding the Impact of Early Citers on Long-Term Scientific Impact"
}
| null | null | null | null | true | null |
10637
| null |
Default
| null | null |
null |
{
"abstract": " Estimating the causal effects of an intervention in the presence of\nconfounding is a frequently occurring problem in applications such as medicine.\nThe task is challenging since there may be multiple confounding factors, some\nof which may be missing, and inferences must be made from high-dimensional,\nnoisy measurements. In this paper, we propose a decision-theoretic approach to\nestimate the causal effects of interventions where a subset of the covariates\nis unavailable for some patients during testing. Our approach uses the\ninformation bottleneck principle to perform a discrete, low-dimensional\nsufficient reduction of the covariate data to estimate a distribution over\nconfounders. In doing so, we can estimate the causal effect of an intervention\nwhere only partial covariate information is available. Our results on a causal\ninference benchmark and a real application for treating sepsis show that our\nmethod achieves state-of-the-art performance, without sacrificing\ninterpretability.\n",
"title": "Cause-Effect Deep Information Bottleneck For Incomplete Covariates"
}
| null | null | null | null | true | null |
10638
| null |
Default
| null | null |
null |
{
"abstract": " It is known that when the multicollinearity exists in the logistic regression\nmodel, variance of maximum likelihood estimator is unstable. As a remedy, in\nthe context of biased shrinkage ridge estimation, Chang (2015) introduced an\nalmost unbiased Liu estimator in the logistic regression model. Making use of\nhis approach, when some prior knowledge in the form of linear restrictions are\nalso available, we introduce a restricted almost unbiased Liu estimator in the\nlogistic regression model. Statistical properties of this newly defined\nestimator are derived and some comparison result are also provided in the form\nof theorems. A Monte Carlo simulation study along with a real data example are\ngiven to investigate the performance of this estimator.\n",
"title": "On the restricted almost unbiased Liu estimator in the Logistic regression model"
}
| null | null | null | null | true | null |
10639
| null |
Default
| null | null |
null |
{
"abstract": " The segmentation of animals from camera-trap images is a difficult task. To\nillustrate, there are various challenges due to environmental conditions and\nhardware limitation in these images. We proposed a multi-layer robust principal\ncomponent analysis (multi-layer RPCA) approach for background subtraction. Our\nmethod computes sparse and low-rank images from a weighted sum of descriptors,\nusing color and texture features as case of study for camera-trap images\nsegmentation. The segmentation algorithm is composed of histogram equalization\nor Gaussian filtering as pre-processing, and morphological filters with active\ncontour as post-processing. The parameters of our multi-layer RPCA were\noptimized with an exhaustive search. The database consists of camera-trap\nimages from the Colombian forest taken by the Instituto de Investigación de\nRecursos Biológicos Alexander von Humboldt. We analyzed the performance of\nour method in inherent and therefore challenging situations of camera-trap\nimages. Furthermore, we compared our method with some state-of-the-art\nalgorithms of background subtraction, where our multi-layer RPCA outperformed\nthese other methods. Our multi-layer RPCA reached 76.17 and 69.97% of average\nfine-grained F-measure for color and infrared sequences, respectively. To our\nbest knowledge, this paper is the first work proposing multi-layer RPCA and\nusing it for camera-trap images segmentation.\n",
"title": "Camera-trap images segmentation using multi-layer robust principal component analysis"
}
| null | null | null | null | true | null |
10640
| null |
Default
| null | null |
null |
{
"abstract": " The bi-Lipschitz geometry is one of the main subjects in the modern approach\nof Singularity Theory. However, it rises from works of important mathematicians\nof the last century, especially Zariski. In this work we investigate the\nBi-Lipschitz equisingularity of families of Essentially Isolated Determinantal\nSingularities inspired by the approach of Mostowski and Gaffney.\n",
"title": "The Bi-Lipschitz Equisingularity of Essentially Isolated Determinantal Singularities"
}
| null | null | null | null | true | null |
10641
| null |
Default
| null | null |
null |
{
"abstract": " We define an action of the extended affine d-strand braid group on the open\npositroid stratum in the Grassmannian Gr(k,n), for d the greatest common\ndivisor of k and n. The action is by quasi-automorphisms of the cluster\nstructure on the Grassmannian, determining a homomorphism from the extended\naffine braid group to the cluster modular group. We also define a\nquasi-isomorphism between the Grassmannian Gr(k,rk) and the Fock-Goncharov\nconfiguration space of 2r-tuples of affine flags for SL(k). This identifies the\ncluster variables, clusters, and cluster modular groups, in these two cluster\nstructures.\nFomin and Pylyavskyy proposed a description of the cluster combinatorics for\nGr(3,n) in terms of Kuperberg's basis of non-elliptic webs. As our main\napplication, we prove many of their conjectures for Gr(3,9) and give a\npresentation for its cluster modular group. We establish similar results for\nGr(4,8). These results rely on the fact that both of these Grassmannians have\nfinite mutation type.\n",
"title": "Braid group symmetries of Grassmannian cluster algebras"
}
| null | null | null | null | true | null |
10642
| null |
Default
| null | null |
null |
{
"abstract": " We introduce a new shape-constrained class of distribution functions on R,\nthe bi-$s^*$-concave class. In parallel to results of Dümbgen, Kolesnyk, and\nWilke (2017) for what they called the class of bi-log-concave distribution\nfunctions, we show that every s-concave density f has a bi-$s^*$-concave\ndistribution function $F$ and that every bi-$s^*$-concave distribution function\nsatisfies $\\gamma (F) \\le 1/(1+s)$ where finiteness of $$ \\gamma (F) \\equiv\n\\sup_{x} F(x) (1-F(x)) \\frac{| f' (x)|}{f^2 (x)}, $$ the Csörgő -\nRévész constant of F, plays an important role in the theory of quantile\nprocesses on $R$.\n",
"title": "Bi-$s^*$-concave distributions"
}
| null | null | null | null | true | null |
10643
| null |
Default
| null | null |
null |
{
"abstract": " This article presents a weak law of large numbers and a central limit theorem\nfor the scaled realised covariation of a bivariate Brownian semistationary\nprocess. The novelty of our results lies in the fact that we derive the\nsuitable asymptotic theory both in a multivariate setting and outside the\nclassical semimartingale framework. The proofs rely heavily on recent\ndevelopments in Malliavin calculus.\n",
"title": "A central limit theorem for the realised covariation of a bivariate Brownian semistationary process"
}
| null | null | null | null | true | null |
10644
| null |
Default
| null | null |
null |
{
"abstract": " Based on geometry optimization and magnetic structure investigations within\ndensity functional theory, unique uranium nitride fluoride UNF, isoelectronic\nwith UO2, is shown to present peculiar differentiated physical properties. Such\nspecificities versus the oxide are related with the mixed anionic sublattices\nand the layered-like tetragonal structure characterized by covalent like\n[U2N2]2+motifs interlayered by ionic like [F2]2- ones and illustrated herein\nwith electron localization function graphs. Particularly the ionocovalent\nchemical picture shows, based on overlap population analyses, stronger U-N\nbonding versus N-F and d(U-N) < d(U-F) distances. Based on LDA+U calculations\nthe ground state magnetic structure is insulating antiferromagnet with 2 Bohr\nMagnetons magnetization per magnetic subcell and ~2 eV band gap.\n",
"title": "First principles investigations of electronic, magnetic and bonding peculiarities of uranium nitride-fluoride UNF"
}
| null | null |
[
"Physics"
] | null | true | null |
10645
| null |
Validated
| null | null |
null |
{
"abstract": " Previously, a seven-cluster pattern claiming to be a universal one in\nbacterial genomes has been reported. Keeping in mind the most popular theory of\nchloroplast origin, we checked whether a similar pattern is observed in\nchloroplast genomes. Surprisingly, eight cluster structure has been found, for\nchloroplasts. The pattern observed for chloroplasts differs rather\nsignificantly, from bacterial one, and from that latter observed for\ncyanobacteria. The structure is provided by clustering of the fragments of\nequal length isolated within a genome so that each fragment is converted in\ntriplet frequency dictionary with non-overlapping triplets with no gaps in\nframe tiling. The points in 63-dimensional space were clustered due to elastic\nmap technique. The eight cluster found in chloroplasts comprises the fragments\nof a genome bearing tRNA genes and exhibiting excessively high\n$\\mathsf{GC}$-content, in comparison to the entire genome.\n",
"title": "Eight-cluster structure of chloroplast genomes differs from similar one observed for bacteria"
}
| null | null |
[
"Quantitative Biology"
] | null | true | null |
10646
| null |
Validated
| null | null |
null |
{
"abstract": " We show how any party can encrypt data for an e-passport holder such that\nonly with physical possession of the e-passport decryption is possible. The\nsame is possible for electronic identity cards and driver licenses. We also\nindicate possible applications. Dutch passports allow for 160 bit security,\ntheoretically giving sufficient security beyond the year 2079, exceeding\ncurrent good practice of 128 bit security. We also introduce the notion of RDE\nExtraction PIN which effectively provides the same security as a regular PIN.\nOur results ironically suggest that carrying a passport when traveling abroad\nmight violate export or import laws on strong cryptography.\n",
"title": "Remote Document Encryption - encrypting data for e-passport holders"
}
| null | null | null | null | true | null |
10647
| null |
Default
| null | null |
null |
{
"abstract": " We show how to perform full likelihood inference for max-stable multivariate\ndistributions or processes based on a stochastic Expectation-Maximisation\nalgorithm, which combines statistical and computational efficiency in\nhigh-dimensions. The good performance of this methodology is demonstrated by\nsimulation based on the popular logistic and Brown--Resnick models, and it is\nshown to provide dramatic computational time improvements with respect to a\ndirect computation of the likelihood. Strategies to further reduce the\ncomputational burden are also discussed.\n",
"title": "Full likelihood inference for max-stable data"
}
| null | null |
[
"Statistics"
] | null | true | null |
10648
| null |
Validated
| null | null |
null |
{
"abstract": " We describe nef vector bundles on a projective space with first Chern class\nthree and second Chern class eight over an algebraically closed field of\ncharacteristic zero by giving them a minimal resolution in terms of a full\nstrong exceptional collection of line bundles.\n",
"title": "Nef vector bundles on a projective space with first Chern class 3 and second Chern class 8"
}
| null | null | null | null | true | null |
10649
| null |
Default
| null | null |
null |
{
"abstract": " The ATLAS collaboration will replace its tracking detector with new all\nsilicon pixel and strip systems. This will allow to cope with the higher\nradiation and occupancy levels expected after the 5-fold increase in the\nluminosity of the LHC accelerator complex (HL-LHC). In the new tracking\ndetector (ITk) pixel modules with increased granularity will implement to\nmaintain the occupancy with a higher track density. In addition, both sensors\nand read-out chips composing the hybrid modules will be produced employing more\nradiation hard technologies with respect to the present pixel detector. Due to\ntheir outstanding performance in terms of radiation hardness, thin n-in-p\nsensors are promising candidates to instrument a section of the new pixel\nsystem. Recently produced and developed sensors of new designs will be\npresented. To test the sensors before interconnection to chips, a punch-through\nbiasing structure has been implemented. Its design has been optimized to\ndecrease the possible tracking efficiency losses observed. After irradiation,\nthey were caused by the punch-through biasing structure. A sensor compatible\nwith the ATLAS FE-I4 chip with a pixel size of 50x250 $\\mathrm{\\mu}$m$^{2}$,\nsubdivided into smaller pixel implants of 30x30 $\\mathrm{\\mu}$m$^{2}$ size was\ndesigned to investigate the performance of the 50x50 $\\mathrm{\\mu}$m$^{2}$\npixel cells foreseen for the HL-LHC. Results on sensor performance of 50x250\nand 50x50 $\\mathrm{\\mu}$m$^{2}$ pixel cells in terms of efficiency, charge\ncollection and electric field properties are obtained with beam tests and the\nTransient Current Technique.\n",
"title": "Performance of irradiated thin n-in-p planar pixel sensors for the ATLAS Inner Tracker upgrade"
}
| null | null | null | null | true | null |
10650
| null |
Default
| null | null |
null |
{
"abstract": " Given an input sound signal and a target virtual sound source, sound\nspatialisation algorithms manipulate the signal so that a listener perceives it\nas though it were emitted from the target source. There exist several\nestablished spatialisation approaches that deliver satisfactory results when\nloudspeakers are used to playback the manipulated signal. As headphones have a\nnumber of desirable characteristics over loudspeakers, such as portability,\nisolation from the surrounding environment, cost and ease of use, it is\ninteresting to explore how a sense of acoustic space can be conveyed through\nthem. This article first surveys traditional spatialisation approaches intended\nfor loudspeakers, and then reviews them with regard to their adaptability to\nheadphones.\n",
"title": "Assessment of sound spatialisation algorithms for sonic rendering with headsets"
}
| null | null | null | null | true | null |
10651
| null |
Default
| null | null |
null |
{
"abstract": " We present a method for identifying the coherent structures associated with\nindividual Lagrangian flow trajectories even where only sparse particle\ntrajectory data is available. The method, based on techniques in spectral graph\ntheory, uses the Coherent Structure Coloring vector and associated eigenvectors\nto analyze the distance in higher-dimensional eigenspace between a selected\nreference trajectory and other tracer trajectories in the flow. By analyzing\nthis distance metric in a hierarchical clustering, the coherent structure of\nwhich the reference particle is a member can be identified. This algorithm is\nproven successful in identifying coherent structures of varying complexities in\ncanonical unsteady flows. Additionally, the method is able to assess the\nrelative coherence of the associated structure in comparison to the surrounding\nflow. Although the method is demonstrated here in the context of fluid flow\nkinematics, the generality of the approach allows for its potential application\nto other unsupervised clustering problems in dynamical systems such as neuronal\nactivity, gene expression, or social networks.\n",
"title": "Identification of individual coherent sets associated with flow trajectories using Coherent Structure Coloring"
}
| null | null | null | null | true | null |
10652
| null |
Default
| null | null |
null |
{
"abstract": " We present a non-parametric joint estimation method for fMRI task activation\nvalues and the hemodynamic response function (HRF). The HRF is modeled as a\nGaussian process, making continuous evaluation possible for jittered paradigms\nand providing a variance estimate at each point.\n",
"title": "Gaussian Processes for HRF estimation for BOLD fMRI"
}
| null | null | null | null | true | null |
10653
| null |
Default
| null | null |
null |
{
"abstract": " We calculate 3-loop master integrals for heavy quark correlators and the\n3-loop QCD corrections to the $\\rho$-parameter. They obey non-factorizing\ndifferential equations of second order with more than three singularities,\nwhich cannot be factorized in Mellin-$N$ space either. The solution of the\nhomogeneous equations is possible in terms of convergent close integer power\nseries as $_2F_1$ Gau\\ss{} hypergeometric functions at rational argument. In\nsome cases, integrals of this type can be mapped to complete elliptic integrals\nat rational argument. This class of functions appears to be the next one\narising in the calculation of more complicated Feynman integrals following the\nharmonic polylogarithms, generalized polylogarithms, cyclotomic harmonic\npolylogarithms, square-root valued iterated integrals, and combinations\nthereof, which appear in simpler cases. The inhomogeneous solution of the\ncorresponding differential equations can be given in terms of iterative\nintegrals, where the new innermost letter itself is not an iterative integral.\nA new class of iterative integrals is introduced containing letters in which\n(multiple) definite integrals appear as factors. For the elliptic case, we also\nderive the solution in terms of integrals over modular functions and also\nmodular forms, using $q$-product and series representations implied by Jacobi's\n$\\vartheta_i$ functions and Dedekind's $\\eta$-function. The corresponding\nrepresentations can be traced back to polynomials out of Lambert--Eisenstein\nseries, having representations also as elliptic polylogarithms, a $q$-factorial\n$1/\\eta^k(\\tau)$, logarithms and polylogarithms of $q$ and their $q$-integrals.\nDue to the specific form of the physical variable $x(q)$ for different\nprocesses, different representations do usually appear. Numerical results are\nalso presented.\n",
"title": "Iterated Elliptic and Hypergeometric Integrals for Feynman Diagrams"
}
| null | null | null | null | true | null |
10654
| null |
Default
| null | null |
null |
{
"abstract": " We propose a novel distributed inference algorithm for continuous graphical\nmodels, by extending Stein variational gradient descent (SVGD) to leverage the\nMarkov dependency structure of the distribution of interest. Our approach\ncombines SVGD with a set of structured local kernel functions defined on the\nMarkov blanket of each node, which alleviates the curse of high dimensionality\nand simultaneously yields a distributed algorithm for decentralized inference\ntasks. We justify our method with theoretical analysis and show that the use of\nlocal kernels can be viewed as a new type of localized approximation that\nmatches the target distribution on the conditional distributions of each node\nover its Markov blanket. Our empirical results show that our method outperforms\na variety of baselines including standard MCMC and particle message passing\nmethods.\n",
"title": "Stein Variational Message Passing for Continuous Graphical Models"
}
| null | null | null | null | true | null |
10655
| null |
Default
| null | null |
null |
{
"abstract": " PEBPs (PhosphatidylEthanolamine Binding Proteins) form a protein family\nwidely present in the living world since they are encountered in\nmicroorganisms, plants and animals. In all organisms PEBPs appear to regulate\nimportant mechanisms that govern cell cycle, proliferation, differentiation and\nmotility. In humans, three PEBPs have been identified, namely PEBP1, PEBP2 and\nPEBP4. PEBP1 and PEBP4 are the most studied as they are implicated in the\ndevelopment of various cancers. PEBP2 is specific of testes in mammals and was\nessentially studied in rats and mice where it is very abundant. A lot of\ninformation has been gained on PEBP1 also named RKIP (Raf Kinase Inhibitory\nprotein) due to its role as a metastasis suppressor in cancer. PEBP1 was also\ndemonstrated to be implicated in Alzheimers disease, diabetes and\nnephropathies. Furthermore, PEBP1 was described to be involved in many cellular\nprocesses, among them are signal transduction, inflammation, cell cycle,\nproliferation, adhesion, differentiation, apoptosis, autophagy, circadian\nrhythm and mitotic spindle checkpoint. On the molecular level, PEBP1 was shown\nto regulate several signaling pathways such as Raf/MEK/ERK, NFkB,\nPI3K/Akt/mTOR, p38, Notch and Wnt. PEBP1 acts by inhibiting most of the kinases\nof these signaling cascades. Moreover, PEBP1 is able to bind to a variety of\nsmall ligands such as ATP, phospholipids, nucleotides, flavonoids or drugs.\nConsidering PEBP1 is a small cytoplasmic protein (21kDa), its involvement in so\nmany diseases and cellular mechanisms is amazing. The aim of this review is to\nhighlight the molecular systems that are common to all these cellular\nmechanisms in order to decipher the specific role of PEBP1. Recent discoveries\nenable us to propose that PEBP1 is a modulator of molecular interactions that\ncontrol signal transduction during membrane and cytoskeleton reorganization.\n",
"title": "PEBP1/RKIP: from multiple functions to a common role in cellular processes"
}
| null | null | null | null | true | null |
10656
| null |
Default
| null | null |
null |
{
"abstract": " Modal description logics feature modalities that capture dependence of\nknowledge on parameters such as time, place, or the information state of\nagents. E.g., the logic S5-ALC combines the standard description logic ALC with\nan S5-modality that can be understood as an epistemic operator or as\nrepresenting (undirected) change. This logic embeds into a corresponding modal\nfirst-order logic S5-FOL. We prove a modal characterization theorem for this\nembedding, in analogy to results by van Benthem and Rosen relating ALC to\nstandard first-order logic: We show that S5-ALC with only local roles is, both\nover finite and over unrestricted models, precisely the bisimulation invariant\nfragment of S5-FOL, thus giving an exact description of the expressive power of\nS5-ALC with only local roles.\n",
"title": "A Characterization Theorem for a Modal Description Logic"
}
| null | null | null | null | true | null |
10657
| null |
Default
| null | null |
null |
{
"abstract": " The existence of a spin-liquid ground state of the $s=1/2$ Heisenberg kagome\nantiferromagnet (KAFM) is well established. Meanwhile, also for the $s=1$\nHeisenberg KAFM evidence for the absence of magnetic long-range order (LRO) was\nfound. Magnetic LRO in Heisenberg KAFMs can emerge by increasing the spin\nquantum number $s$ to $s>1$ and for $s=1$ by an easy-plane anisotropy. In the\npresent paper we discuss the route to magnetic order in $s=1/2$ KAFMs by\nincluding an isotropic interlayer coupling (ILC) $J_\\perp$ as well as an\neasy-plane anisotropy in the kagome layers by using the coupled-cluster method\nto high orders of approximation. We consider ferro- as well as\nantiferromagnetic $J_\\perp$. To discuss the general question for the crossover\nfrom a purely two-dimensional (2D) to a quasi-2D and finally to a\nthree-dimensional system we consider the simplest model of stacked (unshifted)\nkagome layers. Although the ILC of real kagome compounds is often more\nsophisticated, such a geometry of the ILC can be relevant for barlowite. We\nfind that the spin-liquid ground state present for the strictly 2D $s=1/2$\n$XXZ$ KAFM survives a finite ILC, where the spin-liquid region shrinks\nmonotonously with increasing anisotropy. If the ILC becomes large enough (about\n15\\% of intralayer coupling for the isotropic Heisenberg case and about 4\\% for\nthe $XY$ limit) magnetic LRO can be established, where the $q=0$ symmetry is\nfavorable if $J_\\perp$ is of moderate strength. If the strength of the ILC\nfurther increases, $\\sqrt{3}\\times \\sqrt{3}$ LRO can become favorable against\n$q=0$ LRO.\n",
"title": "Emergence of magnetic long-range order in kagome quantum antiferromagnets"
}
| null | null | null | null | true | null |
10658
| null |
Default
| null | null |
null |
{
"abstract": " This paper is about the moment problem on a finite-dimensional vector space\nof continuous functions. We investigate the structure of the convex cone of\nmoment functionals (supporting hyperplanes, exposed faces, inner points) and\ntreat various important special topics on moment functionals (determinacy, set\nof atoms of representing measures, core variety).\n",
"title": "The multidimensional truncated Moment Problem: Atoms, Determinacy, and Core Variety"
}
| null | null | null | null | true | null |
10659
| null |
Default
| null | null |
null |
{
"abstract": " In this paper, we will describe a concept of a cryptocurrency issuance\nprotocol which supports digital currencies in a Proof-of-Work (< PoW >) like\nmanner. However, the methods assume alternative utilization of assets used for\ncryptocurrency creation (rather than purchasing electricity necessary for <\nmining >).\n",
"title": "PROOF OF VALUE ALIENATION (PoVA) - a concept of a cryptocurrency issuance protocol"
}
| null | null | null | null | true | null |
10660
| null |
Default
| null | null |
null |
{
"abstract": " Pairwise ranking methods are the basis of many widely used discriminative\ntraining approaches for structure prediction problems in natural language\nprocessing(NLP). Decomposing the problem of ranking hypotheses into pairwise\ncomparisons enables simple and efficient solutions. However, neglecting the\nglobal ordering of the hypothesis list may hinder learning. We propose a\nlistwise learning framework for structure prediction problems such as machine\ntranslation. Our framework directly models the entire translation list's\nordering to learn parameters which may better fit the given listwise samples.\nFurthermore, we propose top-rank enhanced loss functions, which are more\nsensitive to ranking errors at higher positions. Experiments on a large-scale\nChinese-English translation task show that both our listwise learning framework\nand top-rank enhanced listwise losses lead to significant improvements in\ntranslation quality.\n",
"title": "Top-Rank Enhanced Listwise Optimization for Statistical Machine Translation"
}
| null | null | null | null | true | null |
10661
| null |
Default
| null | null |
null |
{
"abstract": " The analysis in Part I revealed interesting properties for subgradient\nlearning algorithms in the context of stochastic optimization when gradient\nnoise is present. These algorithms are used when the risk functions are\nnon-smooth and involve non-differentiable components. They have been long\nrecognized as being slow converging methods. However, it was revealed in Part I\nthat the rate of convergence becomes linear for stochastic optimization\nproblems, with the error iterate converging at an exponential rate $\\alpha^i$\nto within an $O(\\mu)-$neighborhood of the optimizer, for some $\\alpha \\in\n(0,1)$ and small step-size $\\mu$. The conclusion was established under weaker\nassumptions than the prior literature and, moreover, several important problems\n(such as LASSO, SVM, and Total Variation) were shown to satisfy these weaker\nassumptions automatically (but not the previously used conditions from the\nliterature). These results revealed that sub-gradient learning methods have\nmore favorable behavior than originally thought when used to enable continuous\nadaptation and learning. The results of Part I were exclusive to single-agent\nadaptation. The purpose of the current Part II is to examine the implications\nof these discoveries when a collection of networked agents employs subgradient\nlearning as their cooperative mechanism. The analysis will show that, despite\nthe coupled dynamics that arises in a networked scenario, the agents are still\nable to attain linear convergence in the stochastic case; they are also able to\nreach agreement within $O(\\mu)$ of the optimizer.\n",
"title": "Performance Limits of Stochastic Sub-Gradient Learning, Part II: Multi-Agent Case"
}
| null | null | null | null | true | null |
10662
| null |
Default
| null | null |
null |
{
"abstract": " In this paper, we explore how we should aggregate the degrees of belief of of\na group of agents to give a single coherent set of degrees of belief, when at\nleast some of those agents might be probabilistically incoherent. There are a\nnumber of way of aggregating degrees of belief, and there are a number of ways\nof fixing incoherent degrees of belief. When we have picked one of each, should\nwe aggregate first and then fix, or fix first and then aggregate? Or should we\ntry to do both at once? And when do these different procedures agree with one\nanother? In this paper, we focus particularly on the final question.\n",
"title": "Aggregating incoherent agents who disagree"
}
| null | null |
[
"Computer Science",
"Statistics"
] | null | true | null |
10663
| null |
Validated
| null | null |
null |
{
"abstract": " We consider the problems of robust PAC learning from distributed and\nstreaming data, which may contain malicious errors and outliers, and analyze\ntheir fundamental complexity questions. In particular, we establish lower\nbounds on the communication complexity for distributed robust learning\nperformed on multiple machines, and on the space complexity for robust learning\nfrom streaming data on a single machine. These results demonstrate that gaining\nrobustness of learning algorithms is usually at the expense of increased\ncomplexities. As far as we know, this work gives the first complexity results\nfor distributed and online robust PAC learning.\n",
"title": "On Fundamental Limits of Robust Learning"
}
| null | null |
[
"Computer Science",
"Statistics"
] | null | true | null |
10664
| null |
Validated
| null | null |
null |
{
"abstract": " In this paper, we present a real-time robust multi-view pedestrian detection\nand tracking system for video surveillance using neural networks which can be\nused in dynamic environments. The proposed system consists of two phases:\nmulti-view pedestrian detection and tracking. First, pedestrian detection\nutilizes background subtraction to segment the foreground blob. An adaptive\nbackground subtraction method where each of the pixel of input image models as\na mixture of Gaussians and uses an on-line approximation to update the model\napplies to extract the foreground region. The Gaussian distributions are then\nevaluated to determine which are most likely to result from a background\nprocess. This method produces a steady, real-time tracker in outdoor\nenvironment that consistently deals with changes of lighting condition, and\nlong-term scene change. Second, the Tracking is performed at two phases:\npedestrian classification and tracking the individual subject. A sliding window\nis applied on foreground binary image to select an input window which is used\nfor selecting the input image patches from actually input frame. The neural\nnetworks is used for classification with PHOG features. Finally, a Kalman\nfilter is applied to calculate the subsequent step for tracking that aims at\nfinding the exact position of pedestrians in an input image. The experimental\nresult shows that the proposed approach yields promising performance on\nmulti-view pedestrian detection and tracking on different benchmark datasets.\n",
"title": "Robust Multi-view Pedestrian Tracking Using Neural Networks"
}
| null | null |
[
"Computer Science"
] | null | true | null |
10665
| null |
Validated
| null | null |
null |
{
"abstract": " Ongoing and future surveys with repeat imaging in multiple bands are\nproducing (or will produce) time-spaced measurements of brightness, resulting\nin the identification of large numbers of variable sources in the sky. A large\nfraction of these are periodic variables: compilations of these are of\nscientific interest for a variety of purposes. Unavoidably, the data-sets from\nmany such surveys not only have sparse sampling, but also have embedded\nfrequencies in the observing cadence that beat against the natural\nperiodicities of any object under investigation. Such limitations can make\nperiod determination ambiguous and uncertain. For multi-band data sets with\nasynchronous measurements in multiple pass-bands, we want to maximally utilize\nthe information on periodicity in a manner that is agnostic of differences in\nthe light curve shapes across the different channels. Given large volumes of\ndata, computational efficiency is also at a premium. This paper develops and\npresents a computationally economic method for determining periodicity which\ncombines the results from two different classes of period determination\nalgorithms. The underlying principles are illustrated through examples. The\neffectiveness of this approach for combining asynchronously sampled\nmeasurements in multiple observables that share an underlying fundamental\nfrequency is also demonstrated.\n",
"title": "A Hybrid Algorithm for Period Analysis from Multi-band Data with Sparse and Irregular Sampling for Arbitrary Light Curve Shapes"
}
| null | null | null | null | true | null |
10666
| null |
Default
| null | null |
null |
{
"abstract": " Shafer's belief functions were introduced in the seventies of the previous\ncentury as a mathematical tool in order to model epistemic probability. One of\nthe reasons that they were not picked up by mainstream probability was the lack\nof a behavioral interpretation. In this paper we provide such a behavioral\ninterpretation, and re-derive Shafer's belief functions via a betting\ninterpretation reminiscent of the classical Dutch Book Theorem for probability\ndistributions. We relate our betting interpretation of belief functions to the\nexisting literature.\n",
"title": "A behavioral interpretation of belief functions"
}
| null | null | null | null | true | null |
10667
| null |
Default
| null | null |
null |
{
"abstract": " Photonics sensing has long been valued for its tolerance to harsh\nenvironments where traditional sensing technologies fail. As photonic\ncomponents continue to evolve and find new applications, their tolerance to\nradiation is emerging as an important line of inquiry. Here we report on our\ninvestigation of the impact of gamma-ray exposure on the temperature response\nof fiber Bragg gratings. At 25 degrees C, exposures leading to an accumulated\ndose of up to 600 kGy result in complex dose-dependent drift in Bragg\nwavelength, significantly increasing the uncertainty in temperature\nmeasurements obtained if appreciable dose is delivered over the measurement\ninterval. We note that temperature sensitivity is not severely impacted by the\nintegrated dose, suggesting such devices could be used to measure relative\nchanges in temperature.\n",
"title": "Radiation Hardness of Fiber Bragg Grating Thermometers"
}
| null | null | null | null | true | null |
10668
| null |
Default
| null | null |
null |
{
"abstract": " Inductive inference is the process of extracting general rules from specific\nobservations. This problem also arises in the analysis of biological networks,\nsuch as genetic regulatory networks, where the interactions are complex and the\nobservations are incomplete. A typical task in these problems is to extract\ngeneral interaction rules as combinations of Boolean covariates, that explain a\nmeasured response variable. The inductive inference process can be considered\nas an incompletely specified Boolean function synthesis problem. This\nincompleteness of the problem will also generate spurious inferences, which are\na serious threat to valid inductive inference rules. Using random Boolean data\nas a null model, here we attempt to measure the competition between valid and\nspurious inductive inference rules from a given data set. We formulate two\ngreedy search algorithms, which synthesize a given Boolean response variable in\na sparse disjunct normal form, and respectively a sparse generalized algebraic\nnormal form of the variables from the observation data, and we evaluate\nnumerically their performance.\n",
"title": "On the inherent competition between valid and spurious inductive inferences in Boolean data"
}
| null | null |
[
"Quantitative Biology"
] | null | true | null |
10669
| null |
Validated
| null | null |
null |
{
"abstract": " We present a method for computing stable models of normal logic programs,\ni.e., logic programs extended with negation, in the presence of predicates with\narbitrary terms. Such programs need not have a finite grounding, so traditional\nmethods do not apply. Our method relies on the use of a non-Herbrand universe,\nas well as coinduction, constructive negation and a number of other novel\ntechniques. Using our method, a normal logic program with predicates can be\nexecuted directly under the stable model semantics without requiring it to be\ngrounded either before or during execution and without requiring that its\nvariables range over a finite domain. As a result, our method is quite general\nand supports the use of terms as arguments, including lists and complex data\nstructures. A prototype implementation and non-trivial applications have been\ndeveloped to demonstrate the feasibility of our method.\n",
"title": "Computing Stable Models of Normal Logic Programs Without Grounding"
}
| null | null | null | null | true | null |
10670
| null |
Default
| null | null |
null |
{
"abstract": " This paper presents a comprehensive survey of existing authentication and\nprivacy-preserving schemes for 4G and 5G cellular networks. We start by\nproviding an overview of existing surveys that deal with 4G and 5G\ncommunications, applications, standardization, and security. Then, we give a\nclassification of threat models in 4G and 5G cellular networks in four\ncategories, including, attacks against privacy, attacks against integrity,\nattacks against availability, and attacks against authentication. We also\nprovide a classification of countermeasures into three types of categories,\nincluding, cryptography methods, humans factors, and intrusion detection\nmethods. The countermeasures and informal and formal security analysis\ntechniques used by the authentication and privacy preserving schemes are\nsummarized in form of tables. Based on the categorization of the authentication\nand privacy models, we classify these schemes in seven types, including,\nhandover authentication with privacy, mutual authentication with privacy, RFID\nauthentication with privacy, deniable authentication with privacy,\nauthentication with mutual anonymity, authentication and key agreement with\nprivacy, and three-factor authentication with privacy. In addition, we provide\na taxonomy and comparison of authentication and privacy-preserving schemes for\n4G and 5G cellular networks in form of tables. Based on the current survey,\nseveral recommendations for further research are discussed at the end of this\npaper.\n",
"title": "Security for 4G and 5G Cellular Networks: A Survey of Existing Authentication and Privacy-preserving Schemes"
}
| null | null |
[
"Computer Science"
] | null | true | null |
10671
| null |
Validated
| null | null |
null |
{
"abstract": " Analysis of an organization's computer network activity is a key component of\nearly detection and mitigation of insider threat, a growing concern for many\norganizations. Raw system logs are a prototypical example of streaming data\nthat can quickly scale beyond the cognitive power of a human analyst. As a\nprospective filter for the human analyst, we present an online unsupervised\ndeep learning approach to detect anomalous network activity from system logs in\nreal time. Our models decompose anomaly scores into the contributions of\nindividual user behavior features for increased interpretability to aid\nanalysts reviewing potential cases of insider threat. Using the CERT Insider\nThreat Dataset v6.2 and threat detection recall as our performance metric, our\nnovel deep and recurrent neural network models outperform Principal Component\nAnalysis, Support Vector Machine and Isolation Forest based anomaly detection\nbaselines. For our best model, the events labeled as insider threat activity in\nour dataset had an average anomaly score in the 95.53 percentile, demonstrating\nour approach's potential to greatly reduce analyst workloads.\n",
"title": "Deep Learning for Unsupervised Insider Threat Detection in Structured Cybersecurity Data Streams"
}
| null | null | null | null | true | null |
10672
| null |
Default
| null | null |
null |
{
"abstract": " Consider a dihedral cover $f: Y\\to X$ with $X$ and $Y$ four-manifolds and $f$\nbranched along an oriented surface embedded in $X$ with isolated cone\nsingularities. We prove that only a slice knot can arise as the unique\nsingularity on an irregular dihedral cover $f: Y\\to S^4$ if $Y$ is homotopy\nequivalent to $\\mathbb{CP}^2$ and construct an explicit infinite family of such\ncovers with $Y$ diffeomorphic to $\\mathbb{CP}^2$. An obstruction to a knot\nbeing homotopically ribbon arises in this setting, and we describe a class of\npotential counter-examples to the Slice-Ribbon Conjecture.\nOur tools include lifting a trisection of a singularly embedded surface in a\nfour-manifold $X$ to obtain a trisection of the corresponding irregular\ndihedral branched cover of $X$, when such a cover exists. We also develop a\ncombinatorial procedure to compute, using a formula by the second author, the\ncontribution to the signature of the covering manifold which results from the\npresence of a singularity on the branching set.\n",
"title": "Singular branched covers of four-manifolds"
}
| null | null | null | null | true | null |
10673
| null |
Default
| null | null |
null |
{
"abstract": " We introduce a new sample complexity measure, which we refer to as\nsplit-sample growth rate. For any hypothesis $H$ and for any sample $S$ of size\n$m$, the split-sample growth rate $\\hat{\\tau}_H(m)$ counts how many different\nhypotheses can empirical risk minimization output on any sub-sample of $S$ of\nsize $m/2$. We show that the expected generalization error is upper bounded by\n$O\\left(\\sqrt{\\frac{\\log(\\hat{\\tau}_H(2m))}{m}}\\right)$. Our result is enabled\nby a strengthening of the Rademacher complexity analysis of the expected\ngeneralization error. We show that this sample complexity measure, greatly\nsimplifies the analysis of the sample complexity of optimal auction design, for\nmany auction classes studied in the literature. Their sample complexity can be\nderived solely by noticing that in these auction classes, ERM on any sample or\nsub-sample will pick parameters that are equal to one of the points in the\nsample.\n",
"title": "A Sample Complexity Measure with Applications to Learning Optimal Auctions"
}
| null | null | null | null | true | null |
10674
| null |
Default
| null | null |
null |
{
"abstract": " The inability to interpret the model prediction in semantically and visually\nmeaningful ways is a well-known shortcoming of most existing computer-aided\ndiagnosis methods. In this paper, we propose MDNet to establish a direct\nmultimodal mapping between medical images and diagnostic reports that can read\nimages, generate diagnostic reports, retrieve images by symptom descriptions,\nand visualize attention, to provide justifications of the network diagnosis\nprocess. MDNet includes an image model and a language model. The image model is\nproposed to enhance multi-scale feature ensembles and utilization efficiency.\nThe language model, integrated with our improved attention mechanism, aims to\nread and explore discriminative image feature descriptions from reports to\nlearn a direct mapping from sentence words to image pixels. The overall network\nis trained end-to-end by using our developed optimization strategy. Based on a\npathology bladder cancer images and its diagnostic reports (BCIDR) dataset, we\nconduct sufficient experiments to demonstrate that MDNet outperforms\ncomparative baselines. The proposed image model obtains state-of-the-art\nperformance on two CIFAR datasets as well.\n",
"title": "MDNet: A Semantically and Visually Interpretable Medical Image Diagnosis Network"
}
| null | null |
[
"Computer Science"
] | null | true | null |
10675
| null |
Validated
| null | null |
null |
{
"abstract": " Just a survey on I0: The basics, some things known but never published, some\nthings published but not known.\n",
"title": "I0 and rank-into-rank axioms"
}
| null | null |
[
"Mathematics"
] | null | true | null |
10676
| null |
Validated
| null | null |
null |
{
"abstract": " Given the potential X-ray radiation risk to the patient, low-dose CT has\nattracted a considerable interest in the medical imaging field. The current\nmain stream low-dose CT methods include vendor-specific sinogram domain\nfiltration and iterative reconstruction, but they need to access original raw\ndata whose formats are not transparent to most users. Due to the difficulty of\nmodeling the statistical characteristics in the image domain, the existing\nmethods for directly processing reconstructed images cannot eliminate image\nnoise very well while keeping structural details. Inspired by the idea of deep\nlearning, here we combine the autoencoder, the deconvolution network, and\nshortcut connections into the residual encoder-decoder convolutional neural\nnetwork (RED-CNN) for low-dose CT imaging. After patch-based training, the\nproposed RED-CNN achieves a competitive performance relative to\nthe-state-of-art methods in both simulated and clinical cases. Especially, our\nmethod has been favorably evaluated in terms of noise suppression, structural\npreservation and lesion detection.\n",
"title": "Low-Dose CT with a Residual Encoder-Decoder Convolutional Neural Network (RED-CNN)"
}
| null | null | null | null | true | null |
10677
| null |
Default
| null | null |
null |
{
"abstract": " Let $x\\geq 1$ be a large number, and let $1 \\leq a <q $ be integers such that\n$\\gcd(a,q)=1$ and $q=O(\\log^c)$ with $c>0$ constant. This note proves that the\ncounting function for the number of primes $p \\in \\{p=qn+a: n \\geq1 \\}$ with a\nfixed primitive root $u\\ne \\pm 1, v^2$ has the asymptotic formula\n$\\pi_u(x,q,a)=\\delta(u,q,a)x/ \\log x +O(x/\\log^b x),$ where $\\delta(u,q,a)>0$\nis the density, and $b>c+1$ is a constant.\n",
"title": "Primes In Arithmetic Progressions And Primitive Roots"
}
| null | null | null | null | true | null |
10678
| null |
Default
| null | null |
null |
{
"abstract": " The need to analyze the available large synoptic multi-band surveys drives\nthe development of new data-analysis methods. Photometric redshift estimation\nis one field of application where such new methods improved the results,\nsubstantially. Up to now, the vast majority of applied redshift estimation\nmethods have utilized photometric features. We aim to develop a method to\nderive probabilistic photometric redshift directly from multi-band imaging\ndata, rendering pre-classification of objects and feature extraction obsolete.\nA modified version of a deep convolutional network was combined with a mixture\ndensity network. The estimates are expressed as Gaussian mixture models\nrepresenting the probability density functions (PDFs) in the redshift space. In\naddition to the traditional scores, the continuous ranked probability score\n(CRPS) and the probability integral transform (PIT) were applied as performance\ncriteria. We have adopted a feature based random forest and a plain mixture\ndensity network to compare performances on experiments with data from SDSS\n(DR9). We show that the proposed method is able to predict redshift PDFs\nindependently from the type of source, for example galaxies, quasars or stars.\nThereby the prediction performance is better than both presented reference\nmethods and is comparable to results from the literature. The presented method\nis extremely general and allows us to solve of any kind of probabilistic\nregression problems based on imaging data, for example estimating metallicity\nor star formation rate of galaxies. This kind of methodology is tremendously\nimportant for the next generation of surveys.\n",
"title": "Photometric redshift estimation via deep learning"
}
| null | null | null | null | true | null |
10679
| null |
Default
| null | null |
null |
{
"abstract": " Schizophrenia, a mental disorder that is characterized by abnormal social\nbehavior and failure to distinguish one's own thoughts and ideas from reality,\nhas been associated with structural abnormalities in the architecture of\nfunctional brain networks. Using various methods from network analysis, we\nexamine the effect of two classical therapeutic antipsychotics --- Aripiprazole\nand Sulpiride --- on the structure of functional brain networks of healthy\ncontrols and patients who have been diagnosed with schizophrenia. We compare\nthe community structures of functional brain networks of different individuals\nusing mesoscopic response functions, which measure how community structure\nchanges across different scales of a network. We are able to do a reasonably\ngood job of distinguishing patients from controls, and we are most successful\nat this task on people who have been treated with Aripiprazole. We demonstrate\nthat this increased separation between patients and controls is related only to\na change in the control group, as the functional brain networks of the patient\ngroup appear to be predominantly unaffected by this drug. This suggests that\nAripiprazole has a significant and measurable effect on community structure in\nhealthy individuals but not in individuals who are diagnosed with\nschizophrenia. In contrast, we find for individuals are given the drug\nSulpiride that it is more difficult to separate the networks of patients from\nthose of controls. Overall, we observe differences in the effects of the drugs\n(and a placebo) on community structure in patients and controls and also that\nthis effect differs across groups. We thereby demonstrate that different types\nof antipsychotic drugs selectively affect mesoscale structures of brain\nnetworks, providing support that mesoscale structures such as communities are\nmeaningful functional units in the brain.\n",
"title": "Effect of antipsychotics on community structure in functional brain networks"
}
| null | null | null | null | true | null |
10680
| null |
Default
| null | null |
null |
{
"abstract": " Gaussian Mixture Models are one of the most studied and mature models in\nunsupervised learning. However, outliers are often present in the data and\ncould influence the cluster estimation. In this paper, we study a new model\nthat assumes that data comes from a mixture of a number of Gaussians as well as\na uniform \"background\" component assumed to contain outliers and other\nnon-interesting observations. We develop a novel method based on robust loss\nminimization that performs well in clustering such GMM with a uniform\nbackground. We give theoretical guarantees for our clustering algorithm to\nobtain best clustering results with high probability. Besides, we show that the\nresult of our algorithm does not depend on initialization or local optima, and\nthe parameter tuning is an easy task. By numeric simulations, we demonstrate\nthat our algorithm enjoys high accuracy and achieves the best clustering\nresults given a large enough sample size. Finally, experimental comparisons\nwith typical clustering methods on real datasets witness the potential of our\nalgorithm in real applications.\n",
"title": "Unsupervised Learning of Mixture Models with a Uniform Background Component"
}
| null | null | null | null | true | null |
10681
| null |
Default
| null | null |
null |
{
"abstract": " It is argued based on the results of both numerical modelling and the\nexperiments performed on an artificial substitute of a meadow that the sound\nemitted by animals living in a dense surrounding such as a meadow or shrubs can\nbe used as a tool for detection of motion. Some characteristics of the sound\nemitted by these animals, e.g. its frequency, seem to be adjusted to the meadow\ndensity to optimize the effectiveness of this skill. This kind of sensing the\nenvironment could be used as a useful tool improving detection of mates or\npredators. A study thereof would be important both from the basic-knowledge and\necological points of view (unnatural environmental changes like increasing of a\nnoise or changes in plants species composition can make this sensing\nineffective).\n",
"title": "Sound emitted by some grassland animals as an indicator of motion in the surroundings"
}
| null | null | null | null | true | null |
10682
| null |
Default
| null | null |
null |
{
"abstract": " Investigation of coherent Smith-Purcell Radiation (SPR) spectral\ncharacteristics was performed both experimentally and by numerical simulation.\nThe measurement of SPR spectral line shapes of different diffraction orders was\ncarried out at KEK LUCX facility. A pair of room-temperature Schottky barrier\ndiode (SBD) detectors with sensitivity bands of $60-90$~GHz and $320-460$~GHz\nwas used in the measurements. Reasonable agreement of experimental results and\nsimulations performed with CST Studio Suite justifies the use of different\nnarrow-band SBD detectors to investigate different SPR diffraction orders. It\nwas shown that monochromaticity of the SPR spectral lines increases with\ndiffraction order. The comparison of coherent transition radiation and coherent\nSPR intensities in sub-THz frequency range showed that the brightnesses of both\nradiation mechanisms were comparable. A fine tuning feasibility of the SPR\nspectral lines is discussed.\n",
"title": "Monochromaticity of coherent Smith-Purcell radiation from finite size grating"
}
| null | null | null | null | true | null |
10683
| null |
Default
| null | null |
null |
{
"abstract": " Ground-based telescopes equipped with state-of-the-art spectrographs are able\nto obtain high-resolution transmission and emission spectra of exoplanets that\nprobe the structure and composition of their atmospheres. Various atomic and\nmolecular species, such as Na, CO, H2O have been already detected. Molecular\nspecies have been observed only in the near-infrared while atomic species have\nbeen observed in the visible. In particular, the detection and abundance\ndetermination of water vapor bring important constraints to the planet\nformation process. We search for water vapor in the atmosphere of the exoplanet\nHD189733b using a high-resolution transmission spectrum in the visible obtained\nwith HARPS. We use Molecfit to correct for telluric absorption features. Then\nwe compute the high-resolution transmission spectrum of the planet using 3\ntransit datasets. We finally search for water vapor absorption using a\ncross-correlation technique that combines the signal of 800 individual lines.\nTelluric features are corrected to the noise level. We place a 5-sigma upper\nlimit of 100 ppm on the strength of the 6500 A water vapor band. The 1-sigma\nprecision of 20 ppm on the transmission spectrum demonstrates that space-like\nsensitivity can be achieved from the ground. This approach opens new\nperspectives to detect various atomic and molecular species with future\ninstruments such as ESPRESSO at the VLT. Extrapolating from our results, we\nshow that only 1 transit with ESPRESSO would be sufficient to detect water\nvapor on HD189733b-like hot Jupiter with a cloud-free atmosphere. Upcoming\nnear-IR spectrographs will be even more efficient and sensitive to a wider\nrange of molecular species. Moreover, the detection of the same molecular\nspecies in different bands (e.g. visible and IR) is key to constrain the\nstructure and composition of the atmosphere, such as the presence of Rayleigh\nscattering or aerosols.\n",
"title": "Search for water vapor in the high-resolution transmission spectrum of HD189733b in the visible"
}
| null | null |
[
"Physics"
] | null | true | null |
10684
| null |
Validated
| null | null |
null |
{
"abstract": " K. Borsuk in 1979, in the Topological Conference in Moscow, introduced the\nconcept of the capacity of a compactum. In this paper, we compute the capacity\nof the product of two spheres of the same or different dimensions and the\ncapacity of lense spaces. Also, we present an upper bound for the capacity of a\n$\\mathbb{Z}_n$-complex, i.e., a connected finite 2-dimensional CW-complex with\nfinite cyclic fundamental group $\\mathbb{Z}_n$.\n",
"title": "The Capacity of Some Classes of Polyhedra"
}
| null | null | null | null | true | null |
10685
| null |
Default
| null | null |
null |
{
"abstract": " This paper focuses on a new task, i.e., transplanting a\ncategory-and-task-specific neural network to a generic, modular network without\nstrong supervision. We design a functionally interpretable structure for the\ngeneric network. Like building LEGO blocks, we teach the generic network a new\ncategory by directly transplanting the module corresponding to the category\nfrom a pre-trained network with a few or even without sample annotations. Our\nmethod incrementally adds new categories to the generic network but does not\naffect representations of existing categories. In this way, our method breaks\nthe typical bottleneck of learning a net for massive tasks and categories,\ni.e., the requirement of collecting samples for all tasks and categories at the\nsame time before the learning begins. Thus, we use a new distillation\nalgorithm, namely back-distillation, to overcome specific challenges of network\ntransplanting. Our method without training samples even outperformed the\nbaseline with 100 training samples.\n",
"title": "Network Transplanting (extended abstract)"
}
| null | null | null | null | true | null |
10686
| null |
Default
| null | null |
null |
{
"abstract": " Build systems are an essential part of modern software engineering projects.\nAs software projects change continuously, it is crucial to understand how the\nbuild system changes because neglecting its maintenance can lead to expensive\nbuild breakage. Recent studies have investigated the (co-)evolution of build\nconfigurations and reasons for build breakage, but they did this only on a\ncoarse grained level. In this paper, we present BUILDDIFF, an approach to\nextract detailed build changes from MAVEN build files and classify them into 95\nchange types. In a manual evaluation of 400 build changing commits, we show\nthat BUILDDIFF can extract and classify build changes with an average precision\nand recall of 0.96 and 0.98, respectively. We then present two studies using\nthe build changes extracted from 30 open source Java projects to study the\nfrequency and time of build changes. The results show that the top 10 most\nfrequent change types account for 73% of the build changes. Among them, changes\nto version numbers and changes to dependencies of the projects occur most\nfrequently. Furthermore, our results show that build changes occur frequently\naround releases. With these results, we provide the basis for further research,\nsuch as for analyzing the (co-)evolution of build files with other artifacts or\nimproving effort estimation approaches. Furthermore, our detailed change\ninformation enables improvements of refactoring approaches for build\nconfigurations and improvements of models to identify error-prone build files.\n",
"title": "Extracting Build Changes with BUILDDIFF"
}
| null | null |
[
"Computer Science"
] | null | true | null |
10687
| null |
Validated
| null | null |
null |
{
"abstract": " An essential issue that a freight transportation system faced is how to\ndeliver shipments (OD pairs) on a capacitated physical network optimally; that\nis, to determine the best physical path for each OD pair and assign each OD\npair into the most reasonable freight train service sequence. Instead of\npre-specifying or pre-solving the railcar routing beforehand and optimizing the\ntrain formation plan subsequently, which is a standard practice in China\nrailway system and a widely used method in existing literature to reduce the\nproblem complexity, this paper proposes a non-linear binary programming model\nto address the integrated railcar itinerary and train formation plan\noptimization problem. The model comprehensively considers various operational\nrequirements and a set of capacity constraints, including link capacity, yard\nreclassification capacity and the maximal number of blocks a yard can be\nformed, while trying to minimize the total costs of accumulation,\nreclassification and transportation. An efficient simulated annealing based\nheuristic solution approach is developed to solve the mathematical model. To\ntackle the difficult capacity constraints, we use a penalty function method.\nFurthermore, a customized heuristics for satisfying the operational\nrequirements is designed as well.\n",
"title": "Integrating car path optimization with train formation plan: a non-linear binary programming model and simulated annealing based heuristics"
}
| null | null | null | null | true | null |
10688
| null |
Default
| null | null |
null |
{
"abstract": " Experiments on optical and STM injection of carriers in layered\n$\\mathrm{MX_2}$ materials revealed the formation of nanoscale patterns with\nnetworks and globules of domain walls. This is thought to be responsible for\nthe metallization transition of the Mott insulator and for stabilization of a\n\"hidden\" state. In response, here we present studies of the classical charged\nlattice gas model emulating the superlattice of polarons ubiquitous to the\nmaterial of choice $1T-\\mathrm{TaS_2}$. The injection pulse was simulated by\nintroducing a small random concentration of voids which subsequent evolution\nwas followed by means of Monte Carlo cooling. Below the detected phase\ntransition, the voids gradually coalesce into domain walls forming locally\nconnected globules and then the global network leading to a mosaic\nfragmentation into domains with different degenerate ground states. The\nobtained patterns closely resemble the experimental STM visualizations. The\nsurprising aggregation of charged voids is understood by fractionalization of\ntheir charges across the walls' lines.\n",
"title": "Modeling of networks and globules of charged domain walls observed in pump and pulse induced states"
}
| null | null |
[
"Physics"
] | null | true | null |
10689
| null |
Validated
| null | null |
null |
{
"abstract": " The Japanese comic format known as Manga is popular all over the world. It is\ntraditionally produced in black and white, and colorization is time consuming\nand costly. Automatic colorization methods generally rely on greyscale values,\nwhich are not present in manga. Furthermore, due to copyright protection,\ncolorized manga available for training is scarce. We propose a manga\ncolorization method based on conditional Generative Adversarial Networks\n(cGAN). Unlike previous cGAN approaches that use many hundreds or thousands of\ntraining images, our method requires only a single colorized reference image\nfor training, avoiding the need of a large dataset. Colorizing manga using\ncGANs can produce blurry results with artifacts, and the resolution is limited.\nWe therefore also propose a method of segmentation and color-correction to\nmitigate these issues. The final results are sharp, clear, and in high\nresolution, and stay true to the character's original color scheme.\n",
"title": "cGAN-based Manga Colorization Using a Single Training Image"
}
| null | null |
[
"Computer Science"
] | null | true | null |
10690
| null |
Validated
| null | null |
null |
{
"abstract": " The optical spectrum of liquid water is analyzed by subsystem time-dependent\ndensity functional theory. We provide simple explanations for several important\n(and so far elusive) features. Due to the disordered environment surrounding\neach water molecule, the joint density of states of the liquid is much broader\nthan that of the vapor. This results in a red shifted Urbach tail. Confinement\neffects provided by the first solvation shell are responsible for the blue\nshift of the first absorption peak compared to the vapor. In addition, we also\ncharacterize many-body excitonic effects. These dramatically affect the\nspectral weights at low frequencies, contributing to the refractive index by a\nsmall but significant amount.\n",
"title": "Cooperation and Environment Characterize the Low-Lying Optical Spectrum of Liquid Water"
}
| null | null | null | null | true | null |
10691
| null |
Default
| null | null |
null |
{
"abstract": " Type II Weyl semimetal, a three dimensional gapless topological phase, has\ndrawn enormous interest recently. These topological semimetals enjoy overtilted\ndispersion and Weyl nodes that separate the particle and hole pocket. Using\nperturbation renormalization group, we identify possible renormalization of the\ninteraction vertices, which show a tendency toward instability. We further\nadopt a self-consistent mean-field approach to study possible instability of\nthe type II Weyl semimetals under short-range electron-electron interaction. It\nis found that the instabilities are much easier to form in type II Weyl\nsemimetals than the type I case. Eight different mean-field orders are\nidentified, among which we further show that the polar charge density wave\n(CDW) phase exhibits the lowest energy. This CDW order is originated from the\nnesting of the Fermi surfaces and could be a possible ground state in\ninteracting type II Weyl semimetals.\n",
"title": "Possible particle-hole instabilities in interacting type-II Weyl semimetals"
}
| null | null | null | null | true | null |
10692
| null |
Default
| null | null |
null |
{
"abstract": " We present a simple model for the development of shear layers between\nparallel flows in confining channels. Such flows are important across a wide\nrange of topics from diffusers, nozzles and ducts to urban air flow and\ngeophysical fluid dynamics. The model approximates the flow in the shear layer\nas a linear profile separating uniform-velocity streams. Both the channel\ngeometry and wall drag affect the development of the flow. The model shows good\nagreement with both particle-image-velocimetry experiments and computational\nturbulence modelling. The low computational cost of the model allows it to be\nused for design purposes, which we demonstrate by investigating optimal\npressure recovery in diffusers with non-uniform inflow.\n",
"title": "Turbulent shear layers in confining channels"
}
| null | null | null | null | true | null |
10693
| null |
Default
| null | null |
null |
{
"abstract": " Materials composed of two dimensional layers bonded to one another through\nweak van der Waals interactions often exhibit strongly anisotropic behaviors\nand can be cleaved into very thin specimens and sometimes into monolayer\ncrystals. Interest in such materials is driven by the study of low dimensional\nphysics and the design of functional heterostructures. Binary compounds with\nthe compositions MX2 and MX3 where M is a metal cation and X is a halogen anion\noften form such structures. Magnetism can be incorporated by choosing a\ntransition metal with a partially filled d-shell for M, enabling ferroic\nresponses for enhanced functionality. Here a brief overview of binary\ntransition metal dihalides and trihalides is given, summarizing their\ncrystallographic properties and long-range-ordered magnetic structures,\nfocusing on those materials with layered crystal structures and partially\nfilled d-shells required for combining low dimensionality and cleavability with\nmagnetism.\n",
"title": "Crystal and Magnetic Structures in Layered, Transition Metal Dihalides and Trihalides"
}
| null | null | null | null | true | null |
10694
| null |
Default
| null | null |
null |
{
"abstract": " We prove that for any choice of parameters $k,t,\\lambda$ the class of all\nfinite ordered designs with parameters $k,t,\\lambda$ is a Ramsey class.\n",
"title": "Ramsey theorem for designs"
}
| null | null | null | null | true | null |
10695
| null |
Default
| null | null |
null |
{
"abstract": " This paper is a survey of recent results on the adaptive robust non\nparametric methods for the continuous time regression model with the semi -\nmartingale noises with jumps. The noises are modeled by the Lévy processes,\nthe Ornstein -- Uhlenbeck processes and semi-Markov processes. We represent the\ngeneral model selection method and the sharp oracle inequalities methods which\nprovide the robust efficient estimation in the adaptive setting. Moreover, we\npresent the recent results on the improved model selection methods for the\nnonparametric estimation problems.\n",
"title": "Oracle inequalities for the stochastic differential equations"
}
| null | null |
[
"Mathematics"
] | null | true | null |
10696
| null |
Validated
| null | null |
null |
{
"abstract": " We consider the statistical inverse problem to recover $f$ from noisy\nmeasurements $Y = Tf + \\sigma \\xi$ where $\\xi$ is Gaussian white noise and $T$\na compact operator between Hilbert spaces. Considering general reconstruction\nmethods of the form $\\hat f_\\alpha = q_\\alpha \\left(T^*T\\right)T^*Y$ with an\nordered filter $q_\\alpha$, we investigate the choice of the regularization\nparameter $\\alpha$ by minimizing an unbiased estimate of the predictive risk\n$\\mathbb E\\left[\\Vert Tf - T\\hat f_\\alpha\\Vert^2\\right]$. The corresponding\nparameter $\\alpha_{\\mathrm{pred}}$ and its usage are well-known in the\nliterature, but oracle inequalities and optimality results in this general\nsetting are unknown. We prove a (generalized) oracle inequality, which relates\nthe direct risk $\\mathbb E\\left[\\Vert f - \\hat\nf_{\\alpha_{\\mathrm{pred}}}\\Vert^2\\right]$ with the oracle prediction risk\n$\\inf_{\\alpha>0}\\mathbb E\\left[\\Vert Tf - T\\hat f_{\\alpha}\\Vert^2\\right]$. From\nthis oracle inequality we are then able to conclude that the investigated\nparameter choice rule is of optimal order.\nFinally we also present numerical simulations, which support the order\noptimality of the method and the quality of the parameter choice in finite\nsample situations.\n",
"title": "Empirical Risk Minimization as Parameter Choice Rule for General Linear Regularization Methods"
}
| null | null |
[
"Mathematics",
"Statistics"
] | null | true | null |
10697
| null |
Validated
| null | null |
null |
{
"abstract": " We consider a system of linear hyperbolic PDEs where the state at one of the\nboundary points is controlled using the measurements of another boundary point.\nBecause of the disturbances in the measurement, the problem of designing\ndynamic controllers is considered so that the closed-loop system is robust with\nrespect to measurement errors. Assuming that the disturbance is a locally\nessentially bounded measurable function of time, we derive a\ndisturbance-to-state estimate which provides an upper bound on the maximum norm\nof the state (with respect to the spatial variable) at each time in terms of\n$\\mathcal{L}^\\infty$-norm of the disturbance up to that time. The analysis is\nbased on constructing a Lyapunov function for the closed-loop system, which\nleads to controller synthesis and the conditions on system dynamics required\nfor stability. As an application of this stability notion, the problem of\nquantized control for hyperbolic PDEs is considered where the measurements sent\nto the controller are communicated using a quantizer of finite length. The\npresence of quantizer yields practical stability only, and the ultimate bounds\non the norm of the state trajectory are also derived.\n",
"title": "Disturbance-to-State Stabilization and Quantized Control for Linear Hyperbolic Systems"
}
| null | null | null | null | true | null |
10698
| null |
Default
| null | null |
null |
{
"abstract": " The stereodynamics of the Ne($^3$P$_2$)+Ar Penning and Associative ionization\nreactions have been studied using a crossed molecular beam apparatus. The\nexperiment uses a curved magnetic hexapole to polarise the Ne($^3$P$_2$) which\nis then oriented with a shaped magnetic field in the region where it intersects\nwith a beam of Ar($^1$S). The ratios of Penning to associative ionization were\nrecorded over a range of collision energies from 320 cm$^{-1}$ to 500 cm$^{-1}$\nand the data was used to obtain $\\Omega$ state dependent reactivities for the\ntwo reaction channels. These reactivities were found to compare favourably to\nthose predicted in the theoretical work of Brumer et al.\n",
"title": "Energy dependent stereodynamics of the Ne($^3$P$_2$)+Ar reaction"
}
| null | null | null | null | true | null |
10699
| null |
Default
| null | null |
null |
{
"abstract": " We consider tunneling of spinless electrons from a single-channel emitter\ninto an empty collector through an interacting resonant level of the quantum\ndot. When all Coulomb screening of sudden charge variations of the dot during\nthe tunneling is realized by the emitter channel, the system is described with\nan exactly solvable model of a dissipative qubit. To study manifestations of\nthe coherent qubit dynamics in the collector $\\it{a.c.}$ response we derive\nsolution to the corresponding Bloch equation for the model quantum evolution in\nthe presence of the oscillating voltage of frequency $% \\omega$ and calculate\nperturbatively the $\\it{a.c.}$ response in the voltage amplitude. We have shown\nthat in a wide range of the model parameters the coherent qubit dynamics\nresults in the non-zero frequencies resonances in the amplitudes dependence of\nthe $\\it{a.c.}$ harmonics and in the jumps of the harmonics phase shifts across\nthe resonances. In the first order the $\\it{a.c.}$ response is directly related\nto the spectral decomposition of the corresponding transient current and\ncontains only the first $\\omega$ harmonic, whose amplitude exhibits resonance\nat $\\omega =\\omega_I $, where $\\omega_I$ is the qubit oscillation frequency. In\nthe second order we have obtained the $2 \\omega$ harmonic of the $\\it{a.c.}$\nresponse with resonances in the frequency dependence of its amplitude at\n$\\omega_I$, $\\omega_I/2$ and zero frequency and also have found the frequency\ndependent shift of the average steady current.\n",
"title": "Qubit dynamics at tunneling Fermi-edge singularity in $\\it{a.c.}$ response"
}
| null | null | null | null | true | null |
10700
| null |
Default
| null | null |
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