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Dec 27, 2015
12/15

Dec 27, 2015
by
S. Vantieghem; D. Cébron; J. Noir

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Motivated by understanding the liquid core dynamics of tidally deformed planets and moons, we present a study of incompressible flow driven by latitudinal libration within rigid triaxial ellipsoids. We first derive a laminar solution for the inviscid equations of motion under the assumption of uniform vorticity flow. This solution exhibits a res- onance if the libration frequency matches the frequency of the spin-over inertial mode. Furthermore, we extend our model by introducing a reduced...

Topics: Fluid Dynamics, Physics

Source: http://arxiv.org/abs/1512.08281

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0.0

Dec 27, 2015
12/15

Dec 27, 2015
by
Zihan Chen; Lijun Gou; Jeffrey E. McClintock; James F. Steiner; Jianfeng Wu; Weiwei Xu; Jerome Orosz; Yanmei Xiang

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The bright soft X-ray transient Nova Muscae 1991 was intensively observed during its entire 8-month outburst using the Large Area Counter (LAC) onboard the Ginga satellite. Recently, we obtained accurate estimates of the mass of the black hole primary, the orbital inclination angle of the system, and the distance. Using these crucial input data and Ginga X-ray spectra, we have measured the spin of the black hole using the continuum-fitting method. For four X-ray spectra of extraordinary quality...

Topics: Astrophysics, High Energy Astrophysical Phenomena, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1601.00615

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Dec 26, 2015
12/15

Dec 26, 2015
by
Jianfeng Wu; Jerome A. Orosz; Jeffrey E. McClintock; Imran Hasan; Charles D. Bailyn; Lijun Gou; Zihan Chen

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The optical counterpart of the black-hole soft X-ray transient Nova Muscae 1991 has brightened by $\Delta{V}\approx0.8$ mag since its return to quiescence 23 years ago. We present the first clear evidence that the brightening of soft X-ray transients in quiescence occurs at a nearly linear rate. This discovery, and our precise determination of the disk component of emission obtained using our $simultaneous$ photometric and spectroscopic data, have allowed us to identify and accurately model...

Topics: Astrophysics, High Energy Astrophysical Phenomena, Solar and Stellar Astrophysics

Source: http://arxiv.org/abs/1601.00616

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1.0

Dec 24, 2015
12/15

Dec 24, 2015
by
Amos Korman; Shay Kutten; Toshimitsu Masuzawa

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This paper demonstrates the usefulness of distributed local verification of proofs, as a tool for the design of self-stabilizing algorithms.In particular, it introduces a somewhat generalized notion of distributed local proofs, and utilizes it for improving the time complexity significantly, while maintaining space optimality. As a result, we show that optimizing the memory size carries at most a small cost in terms of time, in the context of Minimum Spanning Tree (MST). That is, we present...

Topics: Computing Research Repository, Distributed, Parallel, and Cluster Computing

Source: http://arxiv.org/abs/1512.07800

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0.0

Dec 11, 2015
12/15

Dec 11, 2015
by
Youngsik Huh; Seungsang Oh

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In 1991, Negami found an upper bound on the stick number $s(K)$ of a nontrivial knot $K$ in terms of the minimal crossing number $c(K)$ of the knot which is $s(K) \leq 2 c(K)$. In this paper we improve this upper bound to $s(K) \leq \frac{3}{2} (c(K)+1)$. Moreover if $K$ is a non-alternating prime knot, then $s(K) \leq \frac{3}{2} c(K)$.

Topics: Mathematics, Geometric Topology

Source: http://arxiv.org/abs/1512.03592

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0.0

Dec 10, 2015
12/15

Dec 10, 2015
by
Elbaz. I. Abouelmagd; S. M Elshaboury; H. H. Selim

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We offer an analytical study on the dynamics of a two-body problem perturbed by small post-Newtonian relativistic term. We prove that, while the angular momentum is not conserved, the motion is planar. We also show that the energy is subject to small changes due to the relativistic effect. We also offer a periodic solution to this problem, obtained by a method based of separation of timescales. We demonstrate that our solution is more general than the method developed in the book by Brumberg...

Topics: Astrophysics, Astrophysics of Galaxies, Solar and Stellar Astrophysics

Source: http://arxiv.org/abs/1512.03496

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1.0

Nov 19, 2015
11/15

Nov 19, 2015
by
Nathan Fox

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In 1991, Solomon Golomb discovered a quasilinear solution to Hofstadter's Q-recurrence. In this paper, we construct eventual quasipolynomial solutions of all positive degrees to Hofstadter's recurrence.

Topics: Combinatorics, Number Theory, Mathematics

Source: http://arxiv.org/abs/1511.06484

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0.0

Nov 6, 2015
11/15

Nov 6, 2015
by
Ali Akbulut; Vagif Guliyev; Takahiro Noi; Yoshihiro Sawano

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The generalized Morrey space was defined independetly by T. Mizuhara 1991 and E. Nakai in 1994. Generalized Morrey space ${\mathcal M}_{p,\phi}({\mathbb R}^n)$ is equipped with a parameter $0

Topics: Functional Analysis, Mathematics

Source: http://arxiv.org/abs/1511.02020

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Nov 5, 2015
11/15

Nov 5, 2015
by
Luke B. Smith; Montserrat Fuentes; Penny Gordon-Larsen; Brian J. Reich

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Cardiometabolic diseases have substantially increased in China in the past 20 years and blood pressure is a primary modifiable risk factor. Using data from the China Health and Nutrition Survey, we examine blood pressure trends in China from 1991 to 2009, with a concentration on age cohorts and urbanicity. Very large values of blood pressure are of interest, so we model the conditional quantile functions of systolic and diastolic blood pressure. This allows the covariate effects in the middle...

Topics: Statistics, Applications

Source: http://arxiv.org/abs/1511.01641

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Oct 30, 2015
10/15

Oct 30, 2015
by
Jānis Priede; Thomas Arlt; Leo Bühler

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This study is concerned with numerical linear stability analysis of liquid metal flow in a square duct with thin electrically conducting walls subject to a uniform transverse magnetic field. We derive an asymptotic solution for the base flow which is valid not only for high but also moderate magnetic fields. This solution shows that for low wall conductance ratios $c\ll1,$ an extremely strong magnetic field with the Hartmann number $Ha\sim c^{-4}$ is required to attain the asymptotic flow...

Topics: Fluid Dynamics, Physics

Source: http://arxiv.org/abs/1510.09222

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0.0

Oct 26, 2015
10/15

Oct 26, 2015
by
Kai-Lung Sun; Jürgen Schmidt; Frank Spahn

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A kinky and clumpy ringlet shares orbit with the moon Pan in the center of the 320-km wide Encke gap in Saturn's rings (Porco et al., 2005). The ringlet is mainly composed of micron-sized particles (Showalter, 1991, Hedman et al., 2011), implying that these particles may be significantly perturbed by non-gravitational forces, which can limit their lifetimes. We establish a kinetic model considering the birth, evolution, and death of dust in the Encke central ringlet allowing to evaluate the...

Topics: Astrophysics, Earth and Planetary Astrophysics

Source: http://arxiv.org/abs/1510.07730

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0.0

Oct 21, 2015
10/15

Oct 21, 2015
by
Spyridon J. Hatjispyros; Theodoros Nicoleris; Stephen G. Walker

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A density estimation method in a Bayesian nonparametric framework is presented when recorded data are not coming directly from the distribution of interest, but from a length biased version. From a Bayesian perspective, efforts to computationally evaluate posterior quantities conditionally on length biased data were hindered by the inability to circumvent the problem of a normalizing constant. In this paper we present a novel Bayesian nonparametric approach to the length bias sampling problem...

Topics: Statistics Theory, Statistics, Mathematics

Source: http://arxiv.org/abs/1510.06307

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0.0

Oct 13, 2015
10/15

Oct 13, 2015
by
G. A. Leonov; N. V. Kuznetsov

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Nowadays there are a number of surveys and theoretical works devoted to the Lyapunov exponents and Lyapunov dimension, however most of them are devoted to infinite dimensional systems or rely on special ergodic properties of the system. At the same time the provided illustrative examples are often finite dimensional systems and the rigorous proof of their ergodic properties can be a difficult task. Also the Lyapunov exponents and Lyapunov dimension have become so widespread and common that they...

Topics: Dynamical Systems, Mathematics

Source: http://arxiv.org/abs/1510.03835

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0.0

Oct 9, 2015
10/15

Oct 9, 2015
by
W. Kollatschny; N. Schartel; M. Zetzl; M. Santos-Lleó; P. M. Rodríguez-Pascual; L. Ballo; A. Talavera

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The object PG 0043+039 has been identified as a broad absorption line (BAL) quasar based on its UV spectra. However, this optical luminous quasar has not been detected before in deep X-ray observations, making it the most extreme X-ray weak quasar known today. This study aims to detect PG 0043+039 in a deep X-ray exposure. The question is what causes the extreme X-ray weakness of PG 0043+039? Does PG 0043+039 show other spectral or continuum peculiarities? We took simultaneous deep X-ray...

Topics: Astrophysics, Astrophysics of Galaxies

Source: http://arxiv.org/abs/1510.02681

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2.0

Oct 2, 2015
10/15

Oct 2, 2015
by
Lauri Loiskekoski; Günter M. Ziegler

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We show that by cutting off the vertices and then the edges of neighborly cubical polytopes, one obtains simple 4-dimensional polytopes with n vertices such that all separators of the graph have size at least $\Omega(n/\log^{3/2}n)$. This disproves a conjecture by Kalai from 1991/2004.

Topics: Combinatorics, Metric Geometry, Mathematics

Source: http://arxiv.org/abs/1510.00511

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1.0

Sep 30, 2015
09/15

Sep 30, 2015
by
Deepak Bal; Louis DeBiasio

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Erd\H{o}s, Gy\'arf\'as, and Pyber (1991) conjectured that every $r$-colored complete graph can be partitioned into at most $r-1$ monochromatic components; this is a strengthening of a conjecture of Lov\'asz (1975) in which the components are only required to form a cover. An important partial result of Haxell and Kohayakawa (1995) shows that a partition into $r$ monochromatic components is possible for sufficiently large $r$-colored complete graphs. We start by extending Haxell and Kohayakawa's...

Topics: Combinatorics, Mathematics

Source: http://arxiv.org/abs/1509.09168

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2.0

Sep 22, 2015
09/15

Sep 22, 2015
by
S. Molkov; A. Lutovinov; M. Falanga

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We have investigated the temporal variability of the X-ray flux measured from the high-mass Xray binary LMCX-4 on time scales from several tens of days to tens of years, i.e., exceeding considerably the orbital period (1.408 days). In particular, we have investigated the 30-day cycle of modulation of the X-ray emission from the source (superorbital or precessional variability) and refined the orbital period and its first derivative. We show that the precession period in the time interval...

Topics: High Energy Astrophysical Phenomena, Astrophysics

Source: http://arxiv.org/abs/1509.06739

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2.0

Sep 21, 2015
09/15

Sep 21, 2015
by
T. S. Eaves; C. P. Caulfield

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We identify `minimal seeds' for turbulence, i.e. initial conditions of the smallest possible total perturbation energy density $E_c$ that trigger turbulence from the laminar state, in stably stratified plane Couette flow using the `direct-adjoint-looping' (DAL) method for finding nonlinear optimal perturbations that optimise the time averaged total dissipation of energy in the flow. These minimal seeds are located adjacent to the edge manifold, the manifold in state space that separates...

Topics: Fluid Dynamics, Physics

Source: http://arxiv.org/abs/1509.06334

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Sep 19, 2015
09/15

Sep 19, 2015
by
Marco Cuturi; Alexandre d'Aspremont

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Mean-reverting assets are one of the holy grails of financial markets: if such assets existed, they would provide trivially profitable investment strategies for any investor able to trade them, thanks to the knowledge that such assets oscillate predictably around their long term mean. The modus operandi of cointegration-based trading strategies [Tsay, 2005, {\S}8] is to create first a portfolio of assets whose aggregate value mean-reverts, to exploit that knowledge by selling short or buying...

Topics: Statistics, Applications, Quantitative Finance, Statistical Finance

Source: http://arxiv.org/abs/1509.05954

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4.0

Sep 11, 2015
09/15

Sep 11, 2015
by
Alice Xiang; Donald B. Rubin

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We examine the possible consequences of a change in law school admissions in the United States from an affirmative action system based on race to one based on socioeconomic class. Using data from the 1991-1996 Law School Admission Council Bar Passage Study, students were reassigned attendance by simulation to law school tiers by transferring the affirmative action advantage for black students to students from low socioeconomic backgrounds. The hypothetical academic outcomes for the students...

Topics: Statistics, Applications

Source: http://arxiv.org/abs/1509.03397

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3.0

Sep 5, 2015
09/15

Sep 5, 2015
by
Roman Kononenko

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This study uses Vector Autoregression (VAR) Methodology as well as Vector Error Correction (VEC) Methodology to examine the existence and direction of causality between economic growth and IMF lending for Ukraine. The paper examines the IMF lending data for the period of 1991-2010. Robust empirical analysis indicates that IMF lending has a negative effect of on Ukraine's economic growth in the short term. Policy implications of this finding are that, despite short-run decline in economic...

Topics: Economics, Quantitative Finance

Source: http://arxiv.org/abs/1509.01741

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4.0

Sep 1, 2015
09/15

Sep 1, 2015
by
T. Mikosch; O. Wintenberger

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In this paper we propagate a large deviations approach for proving limit theory for (generally) multivariate time series with heavy tails. We make this notion precise by introducing regularly varying time series. We provide general large deviation results for functionals acting on a sample path and vanishing in some neighborhood of the origin. We study a variety of such functionals, including large deviations of random walks, their suprema, the ruin functional, and further derive weak limit...

Topics: Statistics, Statistics Theory, Mathematics

Source: http://arxiv.org/abs/1509.00253

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6.0

Aug 29, 2015
08/15

Aug 29, 2015
by
G. A. Leonov; N. V. Kuznetsov; N. A. Korzhemanova; D. V. Kusakin

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The exact Lyapunov dimension formula for the Lorenz system has been analytically obtained first due to G.A.Leonov in 2002 under certain restrictions on parameters, permitting classical values. He used the construction technique of special Lyapunov-type functions developed by him in 1991 year. Later it was shown that the consideration of larger class of Lyapunov-type functions permits proving the validity of this formula for all parameters of the system such that all the equilibria of the system...

Topics: Chaotic Dynamics, Dynamical Systems, Mathematics, Nonlinear Sciences

Source: http://arxiv.org/abs/1508.07498

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1.0

Aug 28, 2015
08/15

Aug 28, 2015
by
A. A. Moiseev; M. Ajello; J. H. Buckley; R. Caputo; E. C. Ferrara; D. H. Hartmann; E. Hays; J. E. McEnery; J. W. Mitchell; R. Ojha; J. S. Perkins; J. L. Racusin; A. W. Smith; D. J. Thompson

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The gamma-ray energy range from a few hundred keV to a few hundred MeV has remained largely unexplored, mainly due to the challenging nature of the measurements, since the pi- oneering, but limited, observations by COMPTEL on the Compton Gamma-Ray Observatory (1991-2000). This energy range is a transition region between thermal and nonthermal processes, and accurate measurements are critical for answering a broad range of astrophysical questions. We are developing a MIDEX-scale wide-aperture...

Topics: High Energy Astrophysical Phenomena, Instrumentation and Methods for Astrophysics, Astrophysics

Source: http://arxiv.org/abs/1508.07349

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3.0

Aug 26, 2015
08/15

Aug 26, 2015
by
Vladimir Lebedev

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We consider the class $C(T)$ of continuous real-valued functions on the circle. For certain classes of functions naturally characterised by the rapidity of decrease of Fourier coefficients we investigate whether it is possible to bring families of functions in $C(T)$ into these classes by a change of variable. This paper was originally published in Matematicheski\v{\i} Sbornik, 181:8 (1990), 1099--1113 (Russian). The English translation, published in Mathematics of the USSR, Sbornik, 70:2...

Topics: Mathematics, Classical Analysis and ODEs

Source: http://arxiv.org/abs/1508.06673

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3.0

Aug 22, 2015
08/15

Aug 22, 2015
by
Boris Beranger; Simone A. Padoan

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Extreme values of real phenomena are events that occur with low frequency, but can have a large impact on real life. These are, in many practical problems, high-dimensional by nature (e.g. Tawn, 1990; Coles and Tawn, 1991). To study these events is of fundamental importance. For this purpose, probabilistic models and statistical methods are in high demand. There are several approaches to modelling multivariate extremes as described in Falk et al. (2011), linked to some extent. We describe an...

Topics: Methodology, Statistics

Source: http://arxiv.org/abs/1508.05561

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4.0

Aug 18, 2015
08/15

Aug 18, 2015
by
Sandro Claudio Lera; Didier Sornette

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We study the performance of the euro/Swiss franc exchange rate in the extraordinary period from September 6, 2011 and January 15, 2015 when the Swiss National Bank enforced a minimum exchange rate of 1.20 Swiss francs per euro. Based on the analogy between Brownian motion in finance and physics, the first-order effect of such a steric constraint would enter a priori in the form of a repulsive entropic force associated with the paths crossing the barrier that are forbidden. Non-parametric...

Topics: Quantitative Finance, Statistical Finance

Source: http://arxiv.org/abs/1508.04754

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3.0

Aug 13, 2015
08/15

Aug 13, 2015
by
P. H. Lundow; I. A. Campbell

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Ising spin glasses with bimodal and Gaussian near-neighbor interaction distributions are studied through numerical simulations. The non-self-averaging (normalized inter-sample variance) parameter $U_{22}(T,L)$ for the spin glass susceptibility (and for higher moments $U_{nn}(T,L)$) is reported for dimensions 2, 3, 4, 5 and 7. In each dimension $d$ the non-self-averaging parameters in the paramagnetic regime vary with the sample size L and the correlation length $\xi(T,L)$ as $U_{nn}(\beta,L) =...

Topics: Disordered Systems and Neural Networks, Condensed Matter

Source: http://arxiv.org/abs/1508.03368

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2.0

Jul 29, 2015
07/15

Jul 29, 2015
by
Suyoung Choi; Hanchul Park

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A fundamental idea in toric topology is that classes of manifolds with well-behaved torus actions (simply, toric spaces) are classified by pairs of simplicial complexes and (non-singular) characteristic maps. The authors in their previous paper provided a new way to find all characteristic maps on a simplicial complex $K(J)$ obtainable by a sequence of wedgings from $K$. The main idea was that characteristic maps on $K$ theoretically determine all possible characteristic maps on a wedge of $K$....

Topics: Algebraic Topology, Mathematics

Source: http://arxiv.org/abs/1507.08306

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0.0

Jul 25, 2015
07/15

Jul 25, 2015
by
Basudeb Datta; Soumen Sarkar

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Quasitoric manifolds, introduced by M. Davis and T. Januskiewicz in 1991, are topological generalizations of smooth complex projective spaces. In 1992, Banchoff and K\"uhnel constructed a 10-vertex equilibrium triangulations of $\CP^2$. We generalize this construction for quasitoric manifolds and construct some equilibrium triangulations of $4$-dimensional quasitoric manifolds. In some cases, our constructions give vertex minimal equilibrium triangulations.

Topics: Mathematics, Geometric Topology

Source: http://arxiv.org/abs/1507.07071

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0.0

Jul 15, 2015
07/15

Jul 15, 2015
by
Piotr Borowiecki; Michael Gentner; Christian Löwenstein; Dieter Rautenbach

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The independence number $\alpha(H)$ of a hypergraph $H$ is the maximum cardinality of a set of vertices of $H$ that does not contain an edge of $H$. Generalizing Shearer's classical lower bound on the independence number of triangle-free graphs (J. Comb. Theory, Ser. B 53 (1991) 300-307), and considerably improving recent results of Li and Zang (SIAM J. Discrete Math. 20 (2006) 96-104) and Chishti et al. (Acta Univ. Sapientiae, Informatica 6 (2014) 132-158), we show that $$\alpha(H)\geq...

Topics: Combinatorics, Mathematics

Source: http://arxiv.org/abs/1507.04323

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2.0

Jul 14, 2015
07/15

Jul 14, 2015
by
Qian Lin; Zhigen Zhao; Jun S. Liu

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We provide here a framework to analyze the phase transition phenomenon of slice inverse regression (SIR), a supervised dimension reduction technique introduced by \cite{Li:1991}. Under mild conditions, the asymptotic ratio $\rho= \lim p/n$ is the phase transition parameter and the SIR estimator is consistent if and only if $\rho= 0$. When dimension $p$ is greater than $n$, we propose a diagonal thresholding screening SIR (DT-SIR) algorithm. This method provides us with an estimate of the...

Topics: Statistics, Statistics Theory, Mathematics

Source: http://arxiv.org/abs/1507.03895

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4.0

Jul 10, 2015
07/15

Jul 10, 2015
by
Mrinmoy Datta; Sudhir R. Ghorpade

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We consider the problem of determining the maximum number of common zeros in a projective space over a finite field for a system of linearly independent multivariate homogeneous polynomials defined over that field. There is an elaborate conjecture of Tsfasman and Boguslavsky that predicts the maximum value when the homogeneous polynomials have the same degree that is not too large in comparison to the size of the finite field. We show that this conjecture holds in the affirmative if the number...

Topics: Mathematics, Algebraic Geometry

Source: http://arxiv.org/abs/1507.03029

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1.0

Jul 7, 2015
07/15

Jul 7, 2015
by
P. H. Lundow; I. A. Campbell

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The critical behaviors of the bimodal and Gaussian Ising spin glass (ISG) models in dimension four are studied through extensive numerical simulations, and from an analysis of high temperature series expansion (HTSE) data of Klein {\it et al.} (1991). The simulations include standard finite size scaling measurements, thermodynamic limit regime measurements, and analyses which provide estimates of critical exponents without any consideration of the critical temperature. The higher order HTSE...

Topics: Disordered Systems and Neural Networks, Condensed Matter

Source: http://arxiv.org/abs/1507.01965

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2.0

Jun 29, 2015
06/15

Jun 29, 2015
by
Pierre Charbit; Irena Penev; Stéphan Thomassé; Nicolas Trotignon

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We prove that there exist perfect graphs of arbitrarily large clique-chromatic number. These graphs can be obtained from cobipartite graphs by repeatedly gluing along cliques. This negatively answers a question raised by Duffus, Sands, Sauer, and Woodrow in [Two-coloring all two-element maximal antichains, J. Combinatorial Theory, Ser. A, 57 (1991), 109-116].

Topics: Combinatorics, Mathematics

Source: http://arxiv.org/abs/1506.08628

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2.0

Jun 22, 2015
06/15

Jun 22, 2015
by
Krishna Kumar Sabapathy

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We introduce a quantum-optical notion of nonclassicality that we call as the process output nonclassicality for multimode quantum channels. The motivation comes from an information-theoretic point of view and the emphasis is on the output states of a channel. We deem a channel to be `classical' if its outputs are always classical irrespective of the input, i.e., if the channel is nonclassicality breaking, and nonclassical otherwise. Our condition is stronger than the one considered by...

Topics: Quantum Physics, Optics, Physics

Source: http://arxiv.org/abs/1506.06706

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1.0

Jun 19, 2015
06/15

Jun 19, 2015
by
T. Szücs; D. Bemmerer; A. Caciolli; Zs. Fülöp; R. Massarczyk; C. Michelagnoli; T. P. Reinhardt; R. Schwengner; M. P. Takács; C. A. Ur; A. Wagner; L. Wagner

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The stable nucleus $^{15}$N is the mirror of $^{15}$O, the bottleneck in the hydrogen burning CNO cycle. Most of the $^{15}$N level widths below the proton emission threshold are known from just one nuclear resonance fluorescence (NRF) measurement, with limited precision in some cases. A recent experiment with the AGATA demonstrator array determined level lifetimes using the Doppler Shift Attenuation Method (DSAM) in $^{15}$O. As a reference and for testing the method, level lifetimes in...

Topic: Nuclear Experiment

Source: http://arxiv.org/abs/1506.06027

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3.0

Jun 10, 2015
06/15

Jun 10, 2015
by
Eric Janofsky

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This thesis studies high-dimensional, continuous-valued pairwise Markov Random Fields. We are particularly interested in approximating pairwise densities whose logarithm belongs to a Sobolev space. For this problem we propose the method of exponential series [Crain, 1974; Barron and Sheu, 1991], which approximates the log density by a finite- dimensional exponential family with the number of sufficient statistics increasing with the sample size. We consider two approaches to estimating these...

Topics: Statistics, Statistics Theory, Mathematics

Source: http://arxiv.org/abs/1506.03537

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6.0

Jun 5, 2015
06/15

Jun 5, 2015
by
Margherita Disertori; Franz Merkl; Silke W. W. Rolles

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We study the nonlinear supersymmetric hyperbolic sigma model introduced by Zirnbauer in 1991. This model can be related to the mixing measure of a vertex- reinforced jump process. We prove that the two-point correlation function has a probabilistic interpretation in terms of connectivity in rooted random spanning forests. Using this interpretation, we dominate the two-point correlation function for general pinning, e.g. for uniform pinning, with the corresponding correlation function with...

Topics: Mathematics, Probability

Source: http://arxiv.org/abs/1506.01852

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5.0

May 27, 2015
05/15

May 27, 2015
by
Yuki Susa

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We investigate the weak measurement experiment demonstrated by Ritchie et al. [N. W. M. Ritchie, J. G. Story, and R. G. Hulet, Phys. Rev. Lett. 66, 1107 (1991)] from the viewpoint of the statistical hypothesis testing for the weak-value amplification proposed by Susa and Tanaka [Y. Susa and S. Tanaka, Phys. Rev. A 92, 012112 (2015)]. We conclude that the weak-value amplification is a better method to determine whether the crystal used in the experiment is birefringent than the measurement...

Topic: Quantum Physics

Source: http://arxiv.org/abs/1505.07199

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3.0

May 26, 2015
05/15

May 26, 2015
by
R. B. Paris

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In 1991, Ursell gave a strong form of Watson's lemma for the Laplace integral \[\int_0^\infty e^{-xt}f(t)\,dt\qquad (x\rightarrow+\infty) \] in which the amplitude function $f(t)$ is regular at the origin and possesses a Maclaurin expansion valid in $0\leq t\leq R$. He showed that if the asymptotic series for the integral as $x\rightarrow+\infty$ is truncated after $rx$ terms, where $0

Topics: Mathematics, Classical Analysis and ODEs

Source: http://arxiv.org/abs/1505.06905

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4.0

May 25, 2015
05/15

May 25, 2015
by
Tomer Kotek; Helmut Veith; Florian Zuleger

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The finite satisfiability problem of monadic second order logic is decidable only on classes of structures of bounded tree-width by the classic result of Seese (1991). We prove the following problem is decidable: Input: (i) A monadic second order logic sentence $\alpha$, and (ii) a sentence $\beta$ in the two-variable fragment of first order logic extended with counting quantifiers. The vocabularies of $\alpha$ and $\beta$ may intersect. Output: Is there a finite structure which satisfies...

Topics: Logic in Computer Science, Computing Research Repository

Source: http://arxiv.org/abs/1505.06622

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2.0

May 22, 2015
05/15

May 22, 2015
by
Artur Czumaj; Peter Davies

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We present two optimal randomized leader election algorithms for multi-hop radio networks, which run in expected time asymptotically equal to the time required to broadcast one message to the entire network. We first observe that, under certain assumptions, a simulation approach of Bar-Yehuda, Golreich and Itai (1991) can be used to obtain an algorithm that for directed and undirected networks elects a leader in $O(D \log\frac{n}{D} + \log^2 n)$ expected time, where $n$ is the number of the...

Topics: Distributed, Parallel, and Cluster Computing, Computing Research Repository

Source: http://arxiv.org/abs/1505.06149

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2.0

May 7, 2015
05/15

May 7, 2015
by
Y. Suhov; S. Yasaei Sekeh; I. Stuhl

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We produce a series of results extending information-theoretical inequalities (discussed by Dembo--Cover--Thomas in 1989-1991) to a weighted version of entropy. The resulting inequalities involve the Gaussian weighted entropy; they imply a number of new relations for determinants of positive-definite matrices.

Topics: Information Theory, Computing Research Repository, Mathematics

Source: http://arxiv.org/abs/1505.01753

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1.0

Apr 27, 2015
04/15

Apr 27, 2015
by
Jakub Šístek; Jan Březina; Bedřich Sousedík

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We extend the Balancing Domain Decomposition by Constraints (BDDC) method to flows in porous media discretised by mixed-hybrid finite elements with combined mesh dimensions. Such discretisations appear when major geological fractures are modelled by 1D or 2D elements inside three-dimensional domains. In this set-up, the global problem as well as the substructure problems have a symmetric saddle-point structure, containing a `penalty' block due to the combination of meshes. We show that the...

Topics: Numerical Analysis, Mathematics

Source: http://arxiv.org/abs/1504.07085

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3.0

Apr 24, 2015
04/15

Apr 24, 2015
by
Michele Rossi; Lea Terracini

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The present paper is devoted to generalizing, inside the class of projective toric varieties, the classification \cite{Batyrev91}, performed by Batyrev in 1991 for smooth complete toric varieties, to the singular $\Q$--factorial case. Moreover, in the first part of the paper the Kleinschmidt classification of smooth complete toric varieties of Picard number 2 \cite{Kleinschmidt} is revised.

Topics: Algebraic Geometry, Mathematics

Source: http://arxiv.org/abs/1504.06515

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Apr 15, 2015
04/15

Apr 15, 2015
by
Hong Zhu; Zhi-Qiang Jiang; Sai-Ping Li; Wei-Xing Zhou

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Although technical trading rules have been widely used by practitioners in financial markets, their profitability still remains controversial. We here investigate the profitability of moving average (MA) and trading range break (TRB) rules by using the Shanghai Stock Exchange Composite Index (SHCI) from May 21, 1992 through December 31, 2013 and Shenzhen Stock Exchange Composite Index (SZCI) from April 3, 1991 through December 31, 2013. The $t$-test is adopted to check whether the mean returns...

Topics: Quantitative Finance, Trading and Market Microstructure, Statistical Finance

Source: http://arxiv.org/abs/1504.04254

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3.0

Apr 13, 2015
04/15

Apr 13, 2015
by
Ricardo A. Maronna; Victor J. Yohai

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We deal with the equivariant estimation of scatter and location for p-dimensional data, giving emphasis to scatter. It it important that the estimators possess both a high efficiency for normal data and a high resistance to outliers, that is, a low bias under contamination. The most frequently employed estimators are not quite satisfactory in this respect. The Minimum Volume Ellipsoid (MVE) and Minimum Covariance Determinant (MCD) estimators are known to have a very low efficiency. S-Estimators...

Topics: Statistics, Mathematics, Statistics Theory

Source: http://arxiv.org/abs/1504.03389

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Apr 9, 2015
04/15

Apr 9, 2015
by
Sarita Rosenstock; James Owen Weatherall

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A classic result in the foundations of Yang-Mills theory, due to J. W. Barrett ["Holonomy and Path Structures in General Relativity and Yang-Mills Theory." Int. J. Th. Phys. 30(9), (1991)], establishes that given a "generalized" holonomy map from the space of piece-wise smooth, closed curves based at some point of a manifold to a Lie group, there exists a principal bundle with that group as structure group and a principal connection on that bundle such that the holonomy map...

Topics: Physics, High Energy Physics - Theory, Mathematics, History and Philosophy of Physics, Mathematical...

Source: http://arxiv.org/abs/1504.02401

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9.0

Mar 31, 2015
03/15

Mar 31, 2015
by
Vladimir Derkach; Mark Malamud

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Let $A$ be a densely defined symmetric operator with equal deficiency indices in a Hilbert space. We introduce the notion of a Weyl function $M(z)$ of $A$ corresponding to an ordinary boundary triplet of the operator $A^*$ and then investigate its basic properties. In particular, a connection with Krein-Langer Q-functions and Krein's type formula for resolvents is discovered. Using this new connection, we show that the resolvent comparability of two proper extensions is equivalent to that of...

Topics: Spectral Theory, Mathematics

Source: http://arxiv.org/abs/1503.08956