April 2015 arXiv papers — page 16
Showing 1,501–1,600 of 8,340 papers
Spontaneous Appearance of Low-dimensional Magnetic Electron System on Semiconductor Nanostructures
cond-mat.mtrl-sciKeisuke Sawada, Jun-Ichi Iwata, Atsushi Oshiyama
We find that spin-polarized ground states emerge in nanofacets which are self-organized on SiC (0001) surfaces. Our large-scale density-functional calculations reveal that the nanofacet formed by bunching of single bilayer steps generates peculiar carbon dangling bond states localized at but extended along step edges. The flat-band characteristics of those C
Hiroyuki Ishida
We investigate the possibility of Higgs inflation with an extended standard model by right-handed neutrinos and scalar dark matter. We find that the masses of the dark matter and one of the right-handed neutrinos should stand around TeV and $10^{-14}$ GeV scale respectively even if the magnitude of tensor-to-scalar ratio indicates sufficiently small value.
Alexander Iksanov, Andrey Pilipenko
A particle moves randomly over the integer points of the real line. Jumps of the particle outside the membrane (a fixed "locally perturbating set") are i.i.d., have zero mean and finite variance, whereas jumps of the particle from the membrane have other distributions with finite means which may be different for different points of the membrane; furt
Khitam Aqel, Issam Louhichi
In this paper, we discuss the commutativity of sums of two quasihomogeneous Toeplitz operators on the Bergman space of the unit disc. Our main result goes in the direction of the conjecture in "Bicommutants of Toeplitz operators" (by I. Louhichi and N. V. Rao. Arch. Math. 91, 2008, 256-264)
K. E. Bassler, Wenjia Liu, B. Schmittmann, R. K. P. Zia
In common descriptions of phase transitions, first order transitions are characterized by discontinuous jumps in the order parameter and normal fluctuations, while second order transitions are associated with no jumps and anomalous fluctuations. Outside this paradigm are systems exhibiting `mixed order transitions' displaying a mixture of these character
Rushun Tian, Zhitao Zhang
Consider the following system of double coupled Schrödinger equations arising from Bose-Einstein condensates etc., \begin{equation*} \left\{\begin{array}{l} -Δu + u =μ_1 u^3 + βuv^2- κv, -Δv + v =μ_2 v^3 + βu^2v- κu, u\neq0, v\neq0\ \hbox{and}\ u, v\in H^1(\R^N), \end{array} \right. \end{equation*}where $μ_1, μ_2$ are positive and fixed, $κ$ and $β$ are line
Simple Derivation of the Lifetime and the Distribution of Faces for a Binary Subdivision Model
physics.soc-phYukio Hayashi
The iterative random subdivision of rectangles is used as a generation model of networks in physics, computer science, and urban planning. However, these researches were independent. We consider some relations in them, and derive fundamental properties for the average lifetime depending on birth-time and the balanced distribution of rectangle faces.
Hooi Sin Ng, Yong Haur Tay, Kim Meng Liang, Hamam Mokayed
Automated car license plate recognition systems are developed and applied for purpose of facilitating the surveillance, law enforcement, access control and intelligent transportation monitoring with least human intervention. In this paper, an algorithm based on SIFT feature points clustering and matching is proposed to address the issue of recognizing Malays
Swapnil Kharche, Jagdish patil, Kanchan Gohad, Bharti Ambetkar
SQL injection attacks, a class of injection flaw in which specially crafted input strings leads to illegal queries to databases, are one of the topmost threats to web applications. A Number of research prototypes and commercial products that maintain the queries structure in web applications have been developed. But these techniques either fail to address th
Rajan Gill, Dana Kulić, Christopher Nielsen
Path following controllers make the output of a control system approach and traverse a pre-specified path with no apriori time parametrization. In this paper we present a method for path following control design applicable to framed curves generated by splines in the workspace of kinematically redundant mechanical systems. The class of admissible paths inclu
Loukas Grafakos, Hanh Van Nguyen
We find optimal conditions on $m$-linear Fourier multipliers to give rise to bounded operators from a product of Hardy spaces $H^{p_j}$, $0<p_j\le 1$, to Lebesgue spaces $L^p$. The conditions we obtain are necessary and sufficient for boundedness and are expressed in terms of $L^2$-based Sobolev spaces. Our results extend those obtained in the linear case ($
Fei Jiang, Song Jiang
We investigate the stabilizing effects of the magnetic fields in the linearized magnetic Rayleigh-Taylor (RT) problem of a nonhomogeneous incompressible viscous magnetohydrodynamic fluid of zero resistivity in the presence of a uniform gravitational field in a three-dimensional bounded domain, in which the velocity of the fluid is non-slip on the boundary. B
Electronic stress tensor analysis of molecules in gas phase of CVD process for GeSbTe alloy
physics.chem-phHiroo Nozaki, Yuji Ikeda, Kazuhide Ichikawa, Akitomo Tachibana
We analyze the electronic structure of molecules which may exist in gas phase of chemical vapor deposition process for GeSbTe alloy using the electronic stress tensor, with special focus on the chemical bonds between Ge, Sb and Te atoms. We find that, from the viewpoint of the electronic stress tensor, they have intermediate properties between alkali metals
M. P. Garcia del Moral, J. M. Pena, A. Restuccia
In this note we explicitly show how the generalization of the T-duality symmetry of the supermembrane theory compactified in M9xT2 can be reduced to a parabolic subgroup of SL(2,Z) that acts non-linearly on the moduli parameters and on the KK and winding charges of the supermembrane. This is a first step towards a deeper understanding of the dual relation be
Trinh Khanh Duy, Tomoyuki Shirai
An explicit formula for the mean spectral measure of a random Jacobi matrix is derived. The matrix may be regarded as the limit of Gaussian beta ensemble (G$β$E) matrices as the matrix size $N$ tends to infinity with the constraint that $N β$ is a constant.
Traveling waves in the nonlocal KPP-Fisher equation: different roles of the right and the left interactions
math.CAKarel Hasik, Jana Kopfová, Petra Nábělková, Sergei Trofimchuk
We consider the nonlocal KPP-Fisher equation $u_t(t,x) = u_{xx}(t,x) + u(t,x)(1-(K *u)(t,x))$ which describes the evolution of population density $u(t,x)$ with respect to time $t$ and location $x$. The non-locality is expressed in terms of the convolution of $u(t, \cdot)$ with kernel $K(\cdot) \geq 0,$ $\int_{\mathbb{R}} K(s)ds =1$. The restrictions $K(s), s
Magnetic fluctuations driven insulator-to-metal transition in Ca(Ir$_{1-x}$Ru$_{x}$)O$_{3}$
cond-mat.str-elJ. Gunasekera, L. Harriger, A. Dahal, T. Heitmann
Magnetic fluctuations in transition metal oxides are a subject of intensive research because of the key role they are expected to play in the transition from the Mott insulator to the unconventional metallic phase of these materials, and also as drivers of superconductivity. Despite much effort, a clear link between magnetic fluctuations and the insulator-to
Imaging superatomic molecular orbitals in a ${\bf C_{60}}$ molecule through four 800-nm photons
cond-mat.mtrl-sciG. P. Zhang, H. P. Zhu, Y. H. Bai, J. Bonacum
Superatomic molecular orbitals (SAMO) in C60 are ideal building blocks for functional nanostructures. However, imaging them spatially in the gas phase has been unsuccessful. It is found experimentally that if C60 is excited by an 800-nm laser, the photoelectron casts an anisotropic velocity image, but the image becomes isotropic if excited at a 400-nm wavele
Optimal Robustness Results for Some Bayesian Procedures and the Relationship to Prior-Data Conflict
math.STLuai Al-Labadi, Michael Evans
The robustness to the prior of Bayesian inference procedures based on a measure of statistical evidence are considered. These inferences are shown to have optimal properties with respect to robustness. Furthermore, a connection between robustness and prior-data conflict is established. In particular, the inferences are shown to be effectively robust when the
Linear Spatial Pyramid Matching Using Non-convex and non-negative Sparse Coding for Image Classification
cs.CVChengqiang Bao, Liangtian He, Yilun Wang
Recently sparse coding have been highly successful in image classification mainly due to its capability of incorporating the sparsity of image representation. In this paper, we propose an improved sparse coding model based on linear spatial pyramid matching(SPM) and Scale Invariant Feature Transform (SIFT ) descriptors. The novelty is the simultaneous non-co
Yingzhou Li, Haizhao Yang, Eileen Martin, Kenneth Ho
The paper introduces the butterfly factorization as a data-sparse approximation for the matrices that satisfy a complementary low-rank property. The factorization can be constructed efficiently if either fast algorithms for applying the matrix and its adjoint are available or the entries of the matrix can be sampled individually. For an $N \times N$ matrix,
Stochastic Galerkin finite element method with local conductivity basis for electrical impedance tomography
math.NANuutti Hyvönen, Matti Leinonen
The objective of electrical impedance tomography is to deduce information about the conductivity inside a physical body from electrode measurements of current and voltage at the object boundary. In this work, the unknown conductivity is modeled as a random field parametrized by its values at a set of pixels. The uncertainty in the pixel values is propagated
Simon Maretzke
Phase contrast imaging seeks to reconstruct the complex refractive index of an unknown sample from scattering intensities, measured for example under illumination with coherent X-rays. By incorporating refraction, this method yields improved contrast compared to purely absorption-based radiography but involves a phase retrieval problem which, in general, all
Robert I. McLachlan, Klas Modin, Hans Munthe-Kaas, Olivier Verdier
Butcher series, also called B-series, are a type of expansion, fundamental in the analysis of numerical integration. Numerical methods that can be expanded in B-series are defined in all dimensions, so they correspond to \emph{sequences of maps}---one map for each dimension. A long-standing problem has been to characterise those sequences of maps that arise
Hanlei Wang
In this paper, we investigate the visual tracking problem for robotic systems without image-space velocity measurement, simultaneously taking into account the uncertainties of the camera model and the manipulator kinematics and dynamics. We propose a new image-space observer that exploits the image-space velocity information contained in the unknown kinemati
False Positives and Other Statistical Errors in Standard Analyses of Eye Movements in Reading
stat.APTitus von der Malsburg, Bernhard Angele
In research on eye movements in reading, it is common to analyze a number of canonical dependent measures to study how the effects of a manipulation unfold over time. Although this gives rise to the well-known multiple comparisons problem, i.e. an inflated probability that the null hypothesis is incorrectly rejected (Type I error), it is accepted standard pr
Emma Yu Jin
Baryshnikov and Romik derived the combinatorial identities for the numbers of the $m$-strip tableaux. This generalized the classical André's theorem for the number of up-down permutations. They asked for a bijective proof for the enumeration of $3$-strip tableaux. In this paper we will provide such a bijective proof. First we count the $3$-strip tableaux
I. Delgado Gaspar, A. Pérez Martínez, G. Piccinelli, Roberto A. Sussman
We undertake a hydrodynamical study of a mixture of tightly coupled primordial radiation, neutrinos, baryons, electrons and positrons, together with a gas of already decoupled dark matter WIMPS and an already existing "frozen" magnetic field in the infinite conductivity regime. Considering this cosmic fluid as the source of a homogeneous but anisotro
Solar science with the Atacama Large Millimeter/submillimeter Array - A new view of our Sun
astro-ph.SRS. Wedemeyer, T. Bastian, R. Brajsa, H. Hudson
The Atacama Large Millimeter/submillimeter Array (ALMA) is a new powerful tool for observing the Sun at high spatial, temporal, and spectral resolution. These capabilities can address a broad range of fundamental scientific questions in solar physics. The radiation observed by ALMA originates mostly from the chromosphere - a complex and dynamic region betwee
Mahdi Ahmadi Borji
In this paper, we have studied polystyrene (PS) and polyethylene (PE) stiffness by 3-dimensional Langevin Molecular Dynamics simulation. Hard polymers have a very small bending, and thus, their end-to-end distance is more than soft polymers. Quantum dot lasers can be established as colloidal particles dipped in a liquid and grafted by polymer brushes to main
Samah A. M. Ghanem
In this paper, we generalize the fundamental relation between the derivative of the mutual information and the minimum mean squared error (MMSE) to multiuser setups. We prove that the derivative of the mutual information with respect to the signal to noise ratio (SNR) is equal to the MMSE plus a covariance induced due to the interference, quantified by a ter
P. Bhupathi, Peter Groszkowski, M. P. DeFeo, Matthew Ware
We investigate the transient dynamics of a lumped-element oscillator based on a dc superconducting quantum interference device (SQUID). The SQUID is shunted with a capacitor forming a nonlinear oscillator with resonance frequency in the range of several GHz. The resonance frequency is varied by tuning the Josephson inductance of the SQUID with on-chip flux l
Synthesis of anisotropic swirling surface acoustic waves by inverse filter, towards integrated generators of acoustical vortices
physics.ins-detAntoine Riaud, Jean-Louis Thomas, Eric Charron, Adrien Bussonnière
From radio-electronics signal analysis to biological samples actuation, surface acoustic waves (SAW) are involved in a multitude of modern devices. Despite this versatility, SAW transducers developed up to date only authorize the synthesis of the most simple standing or progressive waves such as plane and focused waves. In particular, acoustical integrated s
Dmitry V. Zakablukov
Reversible computation is one of the most promising emerging technologies of the future. The usage of reversible circuits in computing devices can lead to a significantly lower power consumption. In this paper we study reversible logic circuits consisting of NOT, CNOT and 2-CNOT gates. We introduce a set $F(n,q)$ of all transformations $\mathbb Z_2^n \to \ma
Amplitude modes and dynamic coexistence of competing orders in multicomponent superconductors
cond-mat.supr-conMaxim Dzero, Maxim Khodas, Alex Levchenko
We study the nonequilibrium dynamics of an electronic model with competing spin-density-wave and unconventional superconductivity in the context of iron pnictides. Focusing on the collisionless regime, we find that magnetic and superconducting order parameters may coexist dynamically after a sudden quench, even though the equilibrium thermodynamic state supp
Total correlations of the diagonal ensemble herald the many-body localization transition
cond-mat.dis-nnJ. Goold, C. Gogolin, S. R. Clark, J. Eisert
The intriguing phenomenon of many-body localization (MBL) has attracted significant interest recently, but a complete characterization is still lacking. In this work, we introduce the total correlations, a concept from quantum information theory capturing multi-partite correlations, to the study of this phenomenon. We demonstrate that the total correlations
Adrian O'Hagan, Arthur White
The Expectation-Maximization (EM) algorithm is a commonly used method for finding the maximum likelihood estimates of the parameters in a mixture model via coordinate ascent. A serious pitfall with the algorithm is that in the case of multimodal likelihood functions, it can get trapped at a local maximum. This problem often occurs when sub-optimal starting v
Brendon Rhoades
Let $W$ be an irreducible real reflection group. Armstrong, Reiner, and the author presented a model for parking functions attached to W and made three increasingly strong conjectures about these objects. The author generalized these objects and conjectures to the Fuss-Catalan level of generality. Even the weakest of these conjectures would imply a collectio
S. D. Odintsov, V. K. Oikonomou
We investigate which Jordan frame $F(R)$ gravity can describe a Type IV singular bouncing cosmological evolution, with special emphasis given near the point at which the Type IV singularity occurs. The cosmological bounce is chosen in such a way so that the bouncing point coincides exactly with Type IV singularity point. The stability of the resulting $F(R)$
Elisabeth Fink
A geodesic $g$ is Morse, for every $L \geq 1, A \geq 0$ there exists a $C=C_g(L,A)$ such that any $(L,A)$-quasi-geodesic connecting two points on $g$ stays $C$-close to $g$. The Morse lemma implies that in a hyperbolic space every geodesic is Morse. Here we prove the converse: If a homogeneous proper geodesic space is such that for every geodesic $g$ and eve
Young-Ho Eom, Michelangelo Puliga, Jasmina Smailović, Igor Mozetič
Large-scale data from social media have a significant potential to describe complex phenomena in real world and to anticipate collective behaviors such as information spreading and social trends. One specific case of study is represented by the collective attention to the action of political parties. Not surprisingly, researchers and stakeholders tried to co
Fernando G. Lobo, Mosab Bazargani
This paper investigates the performance of multistart next ascent hillclimbing and well-known evolutionary algorithms incorporating diversity preservation techniques on instances of the multimodal problem generator. This generator induces a class of problems in the bitstringdomain which is interesting to study from a theoretical perspective in the context of
Andrea Schioppa
For each $β>1$ we construct a family $F_β$ of metric measure spaces which is closed under the operation of taking weak-tangents (i.e.~blow-ups), and such that each element of $F_β$ admits a $(1,P)$-Poincaré inequality if and only if $P>β$.
L. Sriramkumar, Kumar Atmjeet, Rajeev Kumar Jain
We consider the generation of primordial magnetic fields in a class of bouncing models when the electromagnetic action is coupled non-minimally to a scalar field that, say, drives the background evolution. For scale factors that have the power law form at very early times and non-minimal couplings which are simple powers of the scale factor, one can easily s
Philipp Fischer, Alexey Dosovitskiy, Eddy Ilg, Philip Häusser
Convolutional neural networks (CNNs) have recently been very successful in a variety of computer vision tasks, especially on those linked to recognition. Optical flow estimation has not been among the tasks where CNNs were successful. In this paper we construct appropriate CNNs which are capable of solving the optical flow estimation problem as a supervised
Piotr Pokora
In this note we focus on three independent problems on Okounkov bodies for projective varieties. The main goal is to present a geometric version of the classical Fujita Approximation Theorem, a Jow-type theorem and a cardinality formulae for Minkowski bases on a certain class of smooth projective surfaces.
Multi-frequency image reconstruction for radio interferometry. A regularized inverse problem approach
astro-ph.IMAndré Ferrari, Jérémy Deguignet, Chiara Ferrari, David Mary
We describe a "spatio-spectral" deconvolution algorithm for wide-band imaging in radio interferometry. In contrast with the existing multi-frequency reconstruction algorithms, the proposed method does not rely on a model of the sky-brightness spectral distribution. This non-parametric approach can be of particular interest for the new generation of l
Ashraf A. Shahin
Assigning virtual network resources to physical network components, called Virtual Network Embedding, is a major challenge in cloud computing platforms. In this paper, we propose a memetic elitist pareto evolutionary algorithm for virtual network embedding problem, which is called MEPE-VNE. MEPE-VNE applies a non-dominated sorting-based multi-objective evolu
Jiang-Hua Lu, Victor Mouquin
We introduce and study some mixed product Poisson structures on product manifolds associated to Poisson Lie groups and Lie bialgebras. For quasitriangular Lie bialgebras, our construction is equivalent to that of fusion products of quasi-Poisson G-manifolds introduced by Alekseev, Kosmann- Schwarzbach, and Meinrenken. Our primary examples include four series
Manifestation of nematic degrees of freedom in the Raman response function of iron pnictides
cond-mat.str-elUna Karahasanovic, Florian Kretzschmar, Thomas Boehm, Rudi Hackl
We establish a relation between the Raman response function in the $B_{1g}$ channel and the electronic contribution to the nematic susceptibility within the spin-driven approach to electron nematicity of the iron based superconductors. The spin-driven nematic phase, characterized by the broken $C_4$ symmetry, but unbroken $O(3$) spin-rotational symmetry, is
Masanao Ozawa
The notion of equality between two observables will play many important roles in foundations of quantum theory. However, the standard probabilistic interpretation based on the conventional Born formula does not give the probability of equality between two arbitrary observables, since the Born formula gives the probability distribution only for a commuting fa
Marc Claesen, Jesse Davis, Frank De Smet, Bart De Moor
Assessing the performance of a learned model is a crucial part of machine learning. However, in some domains only positive and unlabeled examples are available, which prohibits the use of most standard evaluation metrics. We propose an approach to estimate any metric based on contingency tables, including ROC and PR curves, using only positive and unlabeled
Jesús A. Álvarez López, Ramón Barral Lijó
The main theorem states that any complete connected Riemannian manifold of bounded geometry can be isometrically realized as a leaf with trivial holonomy in a compact Riemannian foliated space.
Bahram Rangipour, Serkan Sütlü
A natural extension of the Hopf-cyclic cohomology, with coefficients, is introduced to encompass topological Hopf algebras. The topological theory allows to work with infinite dimensional Lie algebras. Furthermore, the category of coefficients (AYD modules) over a topological Lie algebra and those over its universal enveloping (Hopf) algebra are isomorphic.
Vadim Gorin, Grigori Olshanski
The present work stemmed from the study of the problem of harmonic analysis on the infinite-dimensional unitary group U(\infty). That problem consisted in the decomposition of a certain 4-parameter family of unitary representations, which replace the nonexisting two-sided regular representation (Olshanski, J. Funct. Anal., 2003, arXiv:0109193). The required
Hengyu Zhou
Self-shrinkers are important geometric objects in the study of mean curvature flows, while the Bernstein Theorem is one of the most profound results in minimal surface theory. We prove a Bernstein type result for graphical self-shrinker surfaces with codimension two in $\mathbb{R}^4$. Namely, under certain natural conditions on the Jacobian of any smooth map
Global Existence of Weak Solutions to the Barotropic Compressible Navier-Stokes Flows with Degenerate Viscosities
math.APJing Li, Zhouping Xin
This paper concerns the existence of global weak solutions to the barotropic compressible Navier-Stokes equations with degenerate viscosity coefficients. We construct suitable approximate system which has smooth solutions satisfying the energy inequality, the BD entropy one, and the Mellet-Vasseur type estimate. Then, after adapting the compactness results d
S. Aalto, S. Martin F. Costagliola, E. Gonzalez-Alfonso, S. Muller
We present high resolution (0."4) IRAM PdBI and ALMA mm and submm observations of the (ultra) luminous infrared galaxies ((U)LIRGs) IRAS17208-0014, Arp220, IC860 and Zw049.057 that reveal intense line emission from vibrationally excited ($ν_2$=1) J=3-2 and 4-3 HCN. The emission is emerging from buried, compact (r<17-70 pc) nuclei that have very high impl
Naoki Kubota
We consider the simple random walk in i.i.d. nonnegative potentials on the multidimensional cubic lattice. Our goal is to investigate the cost paid by the simple random walk for traveling from the origin to a remote location in a landscape of potentials. In particular, we obtain concentration inequalities for the travel cost in unbounded nonnegative potentia
Marcel de Jeu, Frejanne Ruoff
We introduce the notion of a positive spectral measure on a $σ$-algebra, taking values in the positive projections on a Banach lattice. Such a measure generates a bounded positive representation of the bounded measurable functions. If $X$ is a locally compact Hausdorff space, and $π$ is a positive representation of $C_0(X)$ on a KB-space, then $π$ is the res
Igor O. Slieptsov, Igor N. Karnaukhov
Abnormal electronic properties of complex systems require new ideas concerning explanation of their behavior and possibility of realization. In this acticle we show that a colossal magnetoresistance is realized in the state of the topological Kondo insulator, that is similar to the Kondo insulator state in the Kondo lattice. The mechanism of the phenomenon i
Guoqing Wang
Let $\mathcal{S}$ be a commutative semigroup, and let $T$ be a sequence of terms from the semigroup $\mathcal{S}$. We call $T$ an (additively) {\sl irreducible} sequence provided that no sum of its some terms vanishes. Given any element $a$ of $\mathcal{S}$, let ${\rm D}_a(\mathcal{S})$ be the largest length of the irreducible sequence such that the sum of a
Lijun Zhang, Tianbao Yang, Rong Jin, Zhi-Hua Zhou
In this paper, we develop a relative error bound for nuclear norm regularized matrix completion, with the focus on the completion of full-rank matrices. Under the assumption that the top eigenspaces of the target matrix are incoherent, we derive a relative upper bound for recovering the best low-rank approximation of the unknown matrix. Although multiple wor
W. Till Kranz, Anatolij Gelimson, Kun Zhao, Gerard C. L. Wong
Like ants, some microorganisms are known to leave trails on surfaces to communicate. We explore how trail-mediated self-interaction could affect the behavior of individual microorganisms when diffusive spreading of the trail is negligible on the timescale of the microorganism using a simple phenomenological model for an actively moving particle and a finite-
Leonardo Militano, Antonino Orsino, Giuseppe Araniti, Antonella Molinaro
In the future standardization of the 5G networks, in Long Term Evolution (LTE) Release 13 and beyond, Device-to-Device communications (D2D) is recognized as one of the key technologies that will support the 5G architecture. In fact, D2D can be exploited for different proximity-based services (ProSe) where the users discover their neighbors and benefit form d
Giuseppe Araniti, Massimo Condoluci, Antonino Orsino, Antonio Iera
This paper addresses a multi-criteria decision method properly designed to effectively evaluate the most performing strategy for multicast content delivery in Long Term Evolution (LTE) and beyond systems. We compared the legacy conservative-based approach with other promising strategies in literature, i.e., opportunistic multicasting and subgroup-based polic
Lior Bary-Soroker, Yotam Smilansky, Adva Wolf
This paper deals with function field analogues of the famous theorem of Landau which gives the asymptotic density of sums of two squares in $\mathbb{Z}$. We define the analogue of a sum of two squares in $\mathbb{F}_q[T]$ and estimate the number $B_q(n)$ of such polynomials of degree $n$ in two cases. The first case is when $q$ is large and $n$ fixed and the
Aldo de Luca, Luca Q. Zamboni
Given a finite coloring (or finite partition) of the free semigroup $A^+$ over a set $A$, we consider various types of monochromatic factorizations of right sided infinite words $x\in A^ω$. Some stronger versions of the usual notion of monochromatic factorization are introduced. A factorization is called sequentially monochromatic when concatenations of cons
Yohsuke Matsuzawa
Luna's etale slice theorem is a useful theorem for the local study of quotients by reductive algebraic groups. In this article, we show that the slice theorem can also be used to study local structures of invariant Hilbert schemes. By using this method, we show some results on smoothness of invariant Hilbert schemes at closed orbits.
Mikkel Thorup
These notes describe the most efficient hash functions currently known for hashing integers and strings. These modern hash functions are often an order of magnitude faster than those presented in standard text books. They are also simpler to implement, and hence a clear win in practice, but their analysis is harder. Some of the most practical hash functions
Sheng Zhang
A geometrical conclusion: Sierpinski gasket, two Sierpinski gaskets in a line, three Sierpinski gaskets in a line, and four Sierpinski gaskets in a line are self-similar, but five Sierpinski gaskets in a line is not, which is proved in this paper.
More about Neutron Majorana mass from Exotic Instantons: an alternative mechanism in Low-Scale String theory
hep-phAndrea Addazi
We discuss an alternative for Baryon-violating six quarks transitions, in the contest of low scale string theory. In particular, with $M_{S}=10÷10^{3}\rm TeV$, such a transition can be mediated by two color-triplets,through a quartic coupling with down-quarks,generated by exotic instantons, in a calculable and controllable way. We show how FCNCs limits on co
Mark Kozdoba, Shie Mannor
We present a new algorithm for community detection. The algorithm uses random walks to embed the graph in a space of measures, after which a modification of $k$-means in that space is applied. The algorithm is therefore fast and easily parallelizable. We evaluate the algorithm on standard random graph benchmarks, including some overlapping community benchmar
Rami Mochaourab, Rasmus Brandt, Hadi Ghauch, Mats Bengtsson
We consider a MIMO interference channel in which the transmitters and receivers operate in frequency-division duplex mode. In this setting, interference management through coordinated transceiver design necessitates channel state information at the transmitters (CSI-T). The acquisition of CSI-T is done through feedback from the receivers, which entitles a lo
Alexander von Felbert
In this paper we offer a novel type of network model which can capture the precise structure of a financial market based, for example, on empirical findings. With the attached stochastic framework it is further possible to study how an arbitrary network structure and its expected counterparty credit risk are analytically related to each other. This allows us
Dan Liu, Zilong Li, Yifan Cheng, Cosimo Bambi
It is thought that the spacetime geometry around black hole candidates is described by the Kerr solution, but an observational confirmation is still missing. Today, the continuum-fitting method and the analysis of the iron K$α$ line cannot unambiguously test the Kerr paradigm because of the degeneracy among the parameters of the system, in the sense that it
Chongxuan Li, Jun Zhu, Tianlin Shi, Bo Zhang
Deep generative models (DGMs) are effective on learning multilayered representations of complex data and performing inference of input data by exploring the generative ability. However, little work has been done on examining or empowering the discriminative ability of DGMs on making accurate predictions. This paper presents max-margin deep generative models
Hossein Ziaei Nafchi, Rachid Hedjam, Atena Shahkolaei, Mohamed Cheriet
The state-of-the-art pooling strategies for perceptual image quality assessment (IQA) are based on the mean and the weighted mean. They are robust pooling strategies which usually provide a moderate to high performance for different IQAs. Recently, standard deviation (SD) pooling was also proposed. Although, this deviation pooling provides a very high perfor
Ju Sun, Qing Qu, John Wright
We consider the problem of recovering a complete (i.e., square and invertible) matrix $\mathbf A_0$, from $\mathbf Y \in \mathbb R^{n \times p}$ with $\mathbf Y = \mathbf A_0 \mathbf X_0$, provided $\mathbf X_0$ is sufficiently sparse. This recovery problem is central to the theoretical understanding of dictionary learning, which seeks a sparse representatio
An Approximately Optimal Algorithm for Scheduling Phasor Data Transmissions in Smart Grid Networks
cs.ITK. G. Nagananda, P. P. Khargonekar
In this paper, we devise a scheduling algorithm for ordering transmission of synchrophasor data from the substation to the control center in as short a time frame as possible, within the realtime hierarchical communications infrastructure in the electric grid. The problem is cast in the framework of the classic job scheduling with precedence constraints. The
Zhi-Dan Zhao, Ya-Chun Gao, Shi-Min Cai, Tao Zhou
A mass of traces of human activities show rich dynamic patterns. In this article, we comprehensively investigate the dynamic patterns of 50 thousands of researchers' activities in Sciencenet, the largest multi-disciplinary academic community in China. Through statistical analyses, we found that (i) there exists a power-law scaling between the frequency o
Qing Gao, Daoyi Dong, Ian R. Petersen
This paper aims to determine the fault tolerant quantum filter and fault detection equation for a class of open quantum systems coupled to a laser field that is subject to stochastic faults. In order to analyze this class of open quantum systems, we propose a quantum-classical Bayesian inference method based on the definition of a so-called quantum-classical
Emerson Lopes Machado, Cristiano Jacques Miosso, Ricardo von Borries, Murilo Coutinho
We present a theoretical analysis and empirical evaluations of a novel set of techniques for computational cost reduction of classifiers that are based on learned transform and soft-threshold. By modifying optimization procedures for dictionary and classifier training, as well as the resulting dictionary entries, our techniques allow to reduce the bit precis
Navdeep Kaur, Prabhsimran Singh
Looking at the last decade, progress in technology has made a huge impact on our lifestyles. Enhanced use of mobile phones has provided a technological breakthrough, with the latest smartphones capturing the market. The word smartphone is enough for everyone to understand the tremendous potential it brought to the market in terms of economics as well as usab
A. Javadi, I. Söllner, M. Arcari, S. L. Hansen
Strong nonlinear interactions between photons enable logic operations for both classical and quantum-information technology. Unfortunately, nonlinear interactions are usually feeble and therefore all-optical logic gates tend to be inefficient. A quantum emitter deterministically coupled to a propagating mode fundamentally changes the situation, since each ph
Two Trends in Mobile Security: Financial Motives and Transitioning from Static to Dynamic Analysis
cs.CREmre Erturk
The goal of this paper is to analyze the behavior and intent of recent types of privacy invasive Android adware. There are two recent trends in this area: more financial motives instead of ego motives, and the development of more dynamic analysis tools. This paper starts with a review of Android mobile operating system security, and also addresses the pros a
Frédéric Mynard, Mikhail Tkachenko
We examine sufficient conditions for the dual of a topological group to be metrizable and locally compact.
Hector A. Cardenas, Chester Holtz, Maria Janczak, Philip Meyers
In this work, we critique two papers, "A Polynomial-Time Solution to the Clique Problem" by Tamta, Pande, and Dhami, and "A Polynomial-Time Algorithm For Solving Clique Problems" by LaPlante. We summarize and analyze both papers, noting that the algorithms presented in both papers are flawed. We conclude that neither author has successfully e
3D PET image reconstruction based on Maximum Likelihood Estimation Method (MLEM) algorithm
physics.med-phArtur Słomski, Zbigniew Rudy, Tomasz Bednarski, Piotr Białas
Positron emission tomographs (PET) do not measure an image directly. Instead, they measure at the boundary of the field-of-view (FOV) of PET tomograph a sinogram that consists of measurements of the sums of all the counts along the lines connecting two detectors. As there is a multitude of detectors build-in typical PET tomograph structure, there are many po
First measurement of the forward-backward asymmetry in bottom-quark pair production at high mass
hep-exCDF Collaboration, T. Aaltonen, S. Amerio, D. Amidei
We measure the particle-level forward-backward production asymmetry in $b\bar{b}$ pairs with masses $m(b\bar{b})$ larger than 150 GeV/$c^2$, using events with hadronic jets and employing jet charge to distinguish $b$ from $\bar{b}$. The measurement uses 9.5/fb of ppbar collisions at a center of mass energy of 1.96 TeV recorded by the CDF II detector. The asy
Plastic scintillators for positron emission tomography obtained by the bulk polymerization method
physics.ins-detŁukasz Kapłon, Andrzej Kochanowski, Marcin Molenda, Paweł Moskal
This paper describes three methods regarding the production of plastic scintillators. One method appears to be suitable for the manufacturing of plastic scintillator, revealing properties which fulfill the requirements of novel positron emission tomography scanners based on plastic scintillators. The key parameters of the manufacturing process are determined
Searching for Modified Gravity: Scale and Redshift Dependent Constraints from Galaxy Peculiar Velocities
astro-ph.COAndrew Johnson, Chris Blake, Jason Dossett, Jun Koda
We present measurements of both scale- and time-dependent deviations from the standard gravitational field equations. These late-time modifications are introduced separately for relativistic and non-relativistic particles, by way of the parameters $G_{\rm matter}(k,z)$ and $G_{\rm light}(k,z)$ using two bins in both scale and time, with transition wavenumber
Relative entropy for compressible Navier-Stokes equations with density dependent viscosities and applications
math.APDidier Bresch, Pascal Noble, Jean-Paul Vila
Recently, A. Vasseur and C. Yu have proved the existence of global entropy-weak solutions to the compressible Navier-Stokes equations with viscosities $ν(\varrho)=μ\varrho$ and $λ(\varrho)=0$ and a pressure law under the form $p(\varrho)=a\varrho^γ$ with $a>0$ and $γ>1$ constants. In this note, we propose a non-trivial relative entropy for such system in a p
Spectroscopic detection of CIV in a galaxy at z=7.045: Implications for the ionizing spectra of reionization-era galaxies
astro-ph.GADaniel P. Stark, Gregory Walth, Stephane Charlot, Benjamin Clement
We present Keck/MOSFIRE observations of UV metal lines in four bright gravitationally-lensed z~6-8 galaxies behind the cluster Abell 1703. The spectrum of A1703-zd6, a highly-magnified star forming galaxy with a Lyman-alpha redshift of z=7.045, reveals a confident detection of the nebular CIV emission line (unresolved with FWHM < 125 km/s). UV metal lines ar
An analysis of transient impulsive noise in a Poisson field of interferers for wireless channel in substation environments
stat.MEMinh Au, Basile L. Agba, François Gagnon
In substations, the presence of random transient impulsive interference sources makes noise highly non-Gaussian. In this paper, the primary interest is to provide a general model for wireless channel in presence of these transient impulsive noise for space-time signal processing problems. We assume a superposition of independent interference sources randomly
Nikolaos Bekiaris-Liberis, Claudio Roncoli, Markos Papageorgiou
A macroscopic model-based approach for estimation of the traffic state, specifically of the (total) density and flow of vehicles, is developed for the case of "mixed" traffic, i.e., traffic comprising both ordinary and connected vehicles. The development relies on the following realistic assumptions: (i) The density and flow of connected vehicles are
Giulio Bottegal, Gianluigi Pillonetto, Håkan Hjalmarsson
In this paper we introduce a novel method for linear system identification with quantized output data. We model the impulse response as a zero-mean Gaussian process whose covariance (kernel) is given by the recently proposed stable spline kernel, which encodes information on regularity and exponential stability. This serves as a starting point to cast our sy
Ioannis Dalianis, Fotis Farakos
In this article we motivate and review the embedding of the gravitationally enhanced friction mechanism in supergravity. The very interesting feature is that inflationary models which utilize this mechanism drive inflation for a wider range of parameter values and predict lower values for the tensor-to-scalar ratio.
Romain Veltz
The use of stochastic models, in effect piecewise deterministic Markov processes (PDMP), has become increasingly popular especially for the modeling of chemical reactions and cell biophysics. Yet, exact simulation methods, for the simulation of these models in evolving environments, are limited by the need to find the next jumping time at each recursion of t
Grazieli L. C. Carosio, Thomas D. Humphries, Ronald D. Haynes, Colin G. Farquharson
Energy demand has increased considerably with the growth of world population, increasing the interest in the hydrocarbon reservoir management problem. Companies are concerned with maximizing oil recovery while minimizing capital investment and operational costs. A first step in solving this problem is to consider optimal well placement. In this work, we inve