March 2012 arXiv papers — page 19

R. Fassbender, R. Suhada, A. Nastasi

Observational constraints on the average radial distribution profile of AGN in distant galaxy clusters can provide important clues on the triggering mechanisms of AGN activity in dense environments and are essential for a completeness evaluation of cluster selection techniques in the X-ray and mm-wavebands. The aim of this work is a statistical study with XM

Raminder Singh Samra, Harvey B. Richer, Jeremy S. Heyl, Ryan Goldsbury

We have used Gemini North together with the NIRI-ALTAIR adaptive optics imager in the H and K bands to explore the core of the Galactic globular cluster M71 (NGC 6838). We obtained proper motions for 217 stars and have resolved its internal proper motion dispersion. Using a 3.8 year baseline, the proper motion dispersion in the core is found to be 179 +/- 17

Xiaolei Zhang, Ronald J. Buta

We have carried out an initial study of a small sample of nearby spiral and barred galaxies with a broad distribution of Hubble types in order to have a first estimate of the magnitude of their secular mass accretion/excretion rates in the context of bulge building and morphological evolution along the Hubble sequence. The stellar surface density maps of the

Robert Cacioppo, Asim Gangopadhyaya

We present two different paradoxes related to the length contraction in special relativity and explain their resolution.

Stefan Wenger

The purpose of this article is to prove existence of mass minimizing integral currents with prescribed possibly non-compact boundary in all dual Banach spaces and furthermore in certain spaces without linear structure, such as injective metric spaces and Hadamard spaces. We furthermore prove a weak$^*$-compactness theorem for integral currents in dual spaces

Dan Avritzer, Flaviana Andrea Ribeiro, Renato Vidal Martins

We study torsion free sheaves on integral projective curves with at most ordinary cusps as singularities. Adjusting Seshadri's structure from the nodal case to this one, we describe these sheaves by means of a triple defined in the normalization of the curve.

Ci Song, Yan Li, Jing-Ling Chen

In this paper, by searching the relation between the radial part of Higgs harmonic oscillator in the two-dimensional curved space and the generalized CRS harmonic oscillator model, we can find a series of quasi-exact models in two-dimensional curved space based on this relation.

Paula Cristina Vaz, David Martins de Matos, Bruno Martins, Pavel Calado

Literary reading is an important activity for individuals and choosing to read a book can be a long time commitment, making book choice an important task for book lovers and public library users. In this paper we present an hybrid recommendation system to help readers decide which book to read next. We study book and author recommendation in an hybrid recomm

Barnaby Martin

We initiate a program of parameterized proof complexity that aims to provide evidence that FPT is different from W[1]. A similar program already exists for the classes W[2] and W[SAT]. We contrast these programs and prove upper and lower bounds for W[1]-parameterized Resolution.

Fábio José Bertoloto

In this work we study the vector-valued Hardy spaces H p (D; F) (1 \leq p \leq \infty) and their relationship with RNP, ARNP and the UMDP properties. By following the approach of Taylor in the scalar-valued case, we prove that, when F and F have the ARNP property, then H p (D; F) and H q (D; F) are canonically topologically isomorphic (for p, q \in (1, \inft

M. Dall'Ora, K. Kinemuchi, V. Ripepi, C. T. Rodgers

We present a B, V color-magnitude diagram (CMD) of the Milky Way dwarf satellite Ursa Major II (UMa II), spanning the magnitude range from V ~ 15 to V ~ 23.5 mag and extending over a 18 {\times} 18 arcmin2 area centered on the galaxy. Our photometry goes down to about 2 magnitudes below the galaxy's main sequence turn-off, that we detected at V ~ 21.5 ma

P. Petreczky

I review our current understanding of the properties of strongly interacting matter at high temperatures, based upon numerical calculations in lattice QCD. I discuss the chiral and deconfining aspects of the QCD transition, the equation of state, fluctuations of conserved charges, color screening, meson correlation functions, and the determination of some tr

Andy Hammerlindl

An Anosov diffeomorphism is topologically conjugate to an infranilmanifold automorphism if and only if it has polynomial Global Product Structure.

Jani Sainio

We study the thermalization process in the self-interacting curvaton preheating scenario. We solve the evolution of the system with classical lattice simulations with a recently released symplectic PyCOOL program during the resonance and the early thermalization periods and compare the results to the inflaton preheating. After this we calculate the generated

Peter J. Brown, Kyle S. Dawson, David W. Harris, Matthew Olmstead

We compare early ultraviolet (UV) observations of Type Ia Supernovae (SNe Ia) with theoretical predictions for the brightness of the shock associated with the collision between SN ejecta and a companion star. Our simple method is independent of the intrinsic flux from the SN and treats the flux observed with the Swift/Ultra-Violet Optical Telescope (UVOT) as

D0 Collaboration

We present the first search for supersymmetry (SUSY) in Zgamma final states with large missing transverse energy using data corresponding to an integrated luminosity of 6.2 fb-1 collected with the D0 experiment in ppbar collisions at sqrt(s)=1.96 TeV. This signature is predicted in gauge-mediated SUSY-breaking models, where the lightest neutralino is the nex

Maurice A. de Gosson

A positive definite symmetric matrix σ qualifies as a quantum mechanical covariance matrix if and only if σ+(1/2)i\hbarΩ\geq0 where Ω is the standard symplectic matrix. This well-known condition is a strong version of the uncertainty principle, which can be reinterpreted in terms of the topological notion of symplectic capacity, closely related to Gromov&#39

Sachin Jain, Tarun Sharma

In this note we explore the constraints imposed by the existence of equilibrium partition on parity violating charged fluids in 1+1 dimensions at zero derivative order. We write the equilibrium partition function consistent with 1+1 dimensional CPT invariance and which reproduces the correct anomaly in the charge current. The constraints on constitutive rela

Ji Qiang, Chad Mitchell, Robert D. Ryne

In this paper we report on a high-order fast method to numerically calculate wakefield forces in an electron beam given a wake function model. This method is based on a Newton-Cotes quadrature rule for integral approximation and an FFT method for discrete summation that results in an $O(Nlog(N))$ computational cost, where $N$ is the number of grid points. Us

Florian Zuleger, Sumit Gulwani, Moritz Sinn, Helmut Veith

The size-change abstraction (SCA) is an important program abstraction for termination analysis, which has been successfully implemented in many tools for functional and logic programs. In this paper, we demonstrate that SCA is also a highly effective abstract domain for the bound analysis of imperative programs. We have implemented a bound analysis tool base

Mahendra K. Verma, Anando Chaterjee, Supriyo Paul, Sandeep Reddy

Tarang is a general-purpose pseudospectral parallel code for simulating flows involving fluids, magnetohydrodynamics, and Rayleigh-Bénard convection in turbulence and instability regimes. In this paper we present code validation and benchmarking results of Tarang. We performed our simulations on $1024^3$, $2048^3$, and $4096^3$ grids using the {\em HPC syste

A. Payez

In a series of paper, it has been shown that the distribution of polarisation position angles for visible light from quasars is not random in extremely large regions of the sky. As explained in a recent article, the measurement of vanishing circular polarisation for such quasars is an important problem for a mechanism involving the mixing with axion-like par

Esa Järvenpää, Maarit Järvenpää, Tamás Keleti

We study parametrized families of orthogonal projections for which the dimension of the parameter space is strictly less than that of the Grassmann manifold. We answer the natural question of how much the Hausdorff dimension may decrease by verifying the best possible lower bound for the dimension of almost all projections of a finite measure. We also show t

Andreas Schäfer, Jian Zhou

We reexamine the scale dependence of the ETQS (Efremov-Teryaev-Qiu-Sterman) twist-3 matrix element which has been studied already by the four different groups with conflicting results Ref.[1-4]. We find that we can in fact reproduce the results of Ref.[4] with the method Ref.[4] when we treat some subtleties with greater care, thus easing the mentioned confl

O. Solin, E. Ukkonen, L. Haikala

Data mining techniques must be developed and applied to analyse the large public data bases containing hundreds to thousands of millions entries. The aim of this study is to develop methods for locating previously unknown stellar clusters from the UKIDSS Galactic Plane Survey catalogue data. The cluster candidates are computationally searched from pre-filter

D. V. Khomitsky, L. V. Gulyaev, E. Ya. Sherman

We consider joint effects of tunneling and spin-orbit coupling on driven by electric field spin dynamics in a double quantum dot with a multi-level resonance scenario. We demonstrate that tunneling plays the crucial role in the formation of the Rabi-like spin-flip transitions. In contrast to the linear behavior for weak electric fields, the spin flip rate be

C. Thanassoulas, V. Klenvas, G. Verveniotis, N. Zymaris

The time of occurrence of the large EQ that occurred recently in Mexico (March 20th, 2012, Mw = 7.4) is compared to the peak amplitude occurrence time of the local M1 and K1 tidal components. It is shown that the specific EQ occurred one (-1) day before the next following peak of the M1 tidal component, and was delayed for only +20 minutes after the correspo

Y. -c. Ghim, A. R. Field, S. Zoletnik, D. Dunai

The Beam Emission Spectroscopy (BES) turbulence diagnostic on MAST is to be upgraded in June 2010 from a 1D trial system to a 2D imaging system (8 radial \times 4 poloidal channels) based on a newly developed APD array camera. The spatial resolution of the new system is calculated in terms of the point spread function (PSF) to account for the effects of fiel

Gregory D. Saxton, Chao Guo, I-Hsuan Chiu, Bo Feng

In this study, we examine the social networking practices of the 100 largest nonprofit organizations in the United States. More specifically, we develop a comprehensive classification scheme to delineate these organizations' use of Facebook as a stakeholder engagement tool. We find that there are 5 primary categories of Facebook "statuses", which

Lukas Bogunovic, Ralf Eichhorn, Jan Regtmeier, Dario Anselmetti

We theoretically predict and experimentally demonstrate that several different particle species can be separated from each other by means of a ratchet device, consisting of periodically arranged triangular (ratchet) shaped obstacles. We propose an explicit algorithm for suitably tailoring the externally applied, time-dependent voltage protocol so that one or

C. Praetorius, A. Koehl, B. Muenzing, H. Bardenhagen

We use x-ray absorption and magnetic circular dichroism to study electronic configuration and local susceptibility of CePt5/Pt(111) surface alloys from well above to well below the impurity Kondo temperature. The anisotropic paramagnetic response is governed by the hexagonal crystal field and ferromagnetic correlations, with modified parameters for Ce moment

The YETI Collaboration, W. P. Chen, S. C. -L. Hu, R. Errmann

GM Cep in the young (~4 Myr) open cluster Trumpler 37 has been known to be an abrupt variable and to have a circumstellar disk with very active accretion. Our monitoring observations in 2009-2011 revealed the star to show sporadic flare events, each with brightening of < 0.5 mag lasting for days. These brightening events, associated with a color change towar

N. G. Guseva, Y. I. Izotov, K. J. Fricke, C. Henkel

(abridged) Strongly star-forming galaxies of subsolar metallicities are typical of the high-redshift universe. Here we therefore provide accurate data for two low-z analogs, the well-known low-metallicity emission-line galaxies Haro 11 and ESO 338-IG 004. On the basis of Very Large Telescope/X-shooter spectroscopic observations in the wavelength range 3000-2

Mehdi Moussaid, Elsa G. Guillot, Mathieu Moreau, Jerome Fehrenbach

In human crowds as well as in many animal societies, local interactions among individuals often give rise to self-organized collective organizations that offer functional benefits to the group. For instance, flows of pedestrians moving in opposite directions spontaneously segregate into lanes of uniform walking directions. This phenomenon is often referred t

Mahendra K. Verma

Experiments and numerical simulations reveal that in the forward cascade regime, the energy spectrum of two-dimensional turbulence with Ekman friction deviates from Kraichnan&#39;s prediction of $k^{-3}$ power spectrum. In this letter we explain this observation using an analytic model based on variable enstrophy flux arising due to Ekman friction. We derive

J. G. Rodrigo, V. Crespo, H. Suderow, S. Vieira

Superconductors with an odd number of bands crossing the Fermi energy have topologically protected Andreev states at interfaces, including Majorana states in one dimensional geometries. Superconductivity, a low number of 1D channels, large spin orbit coupling, and a sizeable Zeeman energy, are present in lead nanowires produced by nanoindentation of a Pb tip

G. Mazzeo, E. Prati, M. Belli, G. Leti

We study the charge transfer dynamics between a silicon quantum dot and an individual phosphorous donor using the conduction through the quantum dot as a probe for the donor ionization state. We use a silicon n-MOSFET (metal oxide field effect transistor) biased near threshold in the SET regime with two side gates to control both the device conductance and t

François Guenard

In courses on integration theory, Chasles property is usually considered as elementary and so &#34;natural&#34; that this is sometimes left to the reader. When the functions take their values in finite dimensional spaces, the property is always verified, but it no more true in infinite dimensional spaces. We first give an easy-to-understand example of a func

Youssef Bassil, Paul Semaan

At the present time, computers are employed to solve complex tasks and problems ranging from simple calculations to intensive digital image processing and intricate algorithmic optimization problems to computationally-demanding weather forecasting problems. ASR short for Automatic Speech Recognition is yet another type of computational problem whose purpose

Marjorie Batchelor, Polly Brownlee, William Woods

This paper studies a covering map phi from the upper half plane to the complex plane with a triangular lattice excised. This map is interesting as it factorises Klein&#39;s J invariant. Its derivative has properties which are a slight generalisation of modular functions, and (phi&#39;)^6 is a modular function of weight 12. There is a homomorphism from the mo

Michael M. White, Stephen C. Creagh

An analysis is provided of the degradation that arises in the quality factor of a whispering gallery mode when a circular or spherical dielectric cavity is deformed. The large quality factors of such resonators are important to their use in applications such as sensors, wavelength filters or lasers. Yet a straightforward analysis of the effect of shape defor

Youssef Bassil, Paul Semaan

With the advances in computational technologies over the last decade, large organizations have been investing in Information Technology to automate their internal processes to cut costs and efficiently support their business projects. However, this comes to a price. Business requirements always change. Likewise, IT systems constantly evolves as developers ma

F. Fontani, Aina Palau, G. Busquet, A. Isella

The intermediate- to high-mass star-forming region IRAS 20343+4129 is an excellent laboratory to study the influence of high- and intermediate-mass young stellar objects on nearby starless dense cores, and investigate for possible implications in the clustered star formation process. We present 3 mm observations of continuum and rotational transitions of sev

Joana Ascenso, Marco Lombardi, Charles J. Lada, João Alves

Context. The properties of dust grains, in particular their size distribution, are expected to differ from the interstellar medium to the high-density regions within molecular clouds. Since the extinction at near-infrared wavelengths is caused by dust, the extinction law in cores should depart from that found in low-density environments if the dust grains ha

Youssef Bassil, Mohammad Alwani

ASR short for Automatic Speech Recognition is the process of converting a spoken speech into text that can be manipulated by a computer. Although ASR has several applications, it is still erroneous and imprecise especially if used in a harsh surrounding wherein the input speech is of low quality. This paper proposes a post-editing ASR error correction method

Hao Fang, Mijia Lai

We study the convergence behavior of the general inverse $σ_k$-flow on Kähler manifolds with initial metrics satisfying the Calabi Ansatz. The limiting metrics can be either smooth or singular. In the latter case, interesting conic singularities along negatively self-intersected sub-varieties are formed as a result of partial blow-up.

Xuepeng Chen, Hector G. Arce, Michael M. Dunham, Qizhou Zhang

We present high angular resolution SMA and Spitzer observations toward the Bok globule CB17. SMA 1.3mm dust continuum images reveal within CB17 two sources with an angular separation of about 21&#34; (about 5250 AU at a distance of 250 pc). The northwestern continuum source, referred to as CB17 IRS, dominates the infrared emission in the Spitzer images, driv

C. A. Giuppone, M. H. M. Morais, G. Boué, A. C. M. Correia

The HD\,196885 system is composed of a binary star and a planet orbiting the primary. The orbit of the binary is fully constrained by astrometry, but for the planet the inclination with respect to the plane of the sky and the longitude of the node are unknown. Here we perform a full analysis of the HD\,196885 system by exploring the two free parameters of th

Vincent Marin, Benoît Revenu

We present a microscopic computation of the radio emission from air showers initiated by ultra-high energy cosmic rays in the atmosphere. The strategy adopted is to compute each secondary particle contribution of the electromagnetic component and to construct the total signal at any location. SELFAS2 is a code which doesn&#39;t rely on air shower generators

J. Tomaschko, S. Scharinger, V. Leca, J. Nagel

Even after 25 years of research the pairing mechanism and - at least for electron doped compounds - also the order parameter symmetry of the high transition temperature (high-Tc) cuprate superconductors is still under debate. One of the reasons is the complex crystal structure of most of these materials. An exception are the infinite layer (IL) compounds con

B. G. Carlsson, J. Toivanen, A. Pastore

An iterative method we previously proposed to compute nuclear strength functions is developed to allow it to accurately calculate properties of individual nuclear states. The approach is based on the quasi-particle-random-phase approximation (QRPA) and uses an iterative non-hermitian Arnoldi diagonalization method where the QRPA matrix does not have to be ex

Bang Ye Wu, Jun-Lin Guo, Yue-Li Wang

For two vertices $s$ and $t$ in a graph $G=(V,E)$, the next-to-shortest path is an $st$-path which length is minimum amongst all $st$-paths strictly longer than the shortest path length. In this paper we show that, when the graph is undirected and all edge lengths are nonnegative, the problem can be solved in linear time if the distances from $s$ and $t$ to

G. Datta, M. Ghosh

The need for small area estimates is increasingly felt in both the public and private sectors in order to formulate their strategic plans. It is now widely recognized that direct small area survey estimates are highly unreliable owing to large standard errors and coefficients of variation. The reason behind this is that a survey is usually designed to achiev

P. I. Pápics, M. Briquet, A. Baglin, E. Poretti

Context. OB stars are important building blocks of the Universe, but we have only a limited sample of them well understood enough from an asteroseismological point of view to provide feedback on the current evolutionary models. Our study adds one special case to this sample, with more observational constraints than for most of these stars. Aims. Our goal is

Ilya Selyuzhenkov

We report on the measurement of two and three particle azimuthal correlations in Pb-Pb collisions at sqrt(s_NN) = 2.76 TeV recorded with ALICE at the LHC. While two particle azimuthal correlations mainly provide an important information on possible background correlations, the three particle correlator probes the charge separation of hadrons with respect to

Michael Loewenstein, Alexander Kusenko

We report the results of a search for an emission line from radiatively decaying dark matter in the ultra-faint dwarf spheroidal galaxy Willman 1 based on analysis of spectra extracted from XMM-Newton X-ray Observatory data. The observation follows up our analysis of Chandra data of Willman 1 that resulted in line flux upper limits over the Chandra bandpass

Kay Magaard, Robert Wilson

We present a new algorithm for constructing a Chevalley basis for any Chevalley Lie algebra over a finite field. This is a necessary component for some constructive recognition algorithms of exceptional quasisimple groups of Lie type. When applied to a simple Chevalley Lie algebra in characteristic at least 5, our algorithm has complexity involving the 7th p

H. J. Weber

Prime number multiplet classifications and patterns are extended to negative integers. The extension from prime numbers to single prime powers is also studied. Prime number septets at equal distance are given. It is also shown that each class of generalized twin primes of the classification contains a positive fraction of all prime pairs.

J. Ziroff, S. Hame, M. Kochler, A. Bendounan

Using high-resolution photoemission spectroscopy we demonstrate that the electronic structure of several organic monolayer systems, in particular 1,4,5,8-naphthalene tetracarboxylic dianhydride and Copper-phtalocyanine on Ag(111), is characterized by a peculiar excitation feature right at the Fermi level. This feature displays a strong temperature dependence

H. Djapo, N. Paar

Background: Inelastic neutrino-nucleus scattering through the weak neutral-current plays important role in stellar environment where transport of neutrinos determine the rate of cooling. Since there are no direct experimental data on neutral-current neutrino-nucleus cross sections available, only the modeling of these reactions provides the relevant input fo

Robert J. Mokken

In the analysis of social networks many relatively loose and heuristic definitions of &#39;community&#39; abound. In this paper the concept of closely knit communities is studied as defined by the property that every pair of its members are neighbors or has at least one common neighbor, where the neighboring relationship is based on some more or less durable

Stephan Herminghaus

The wetting properties of solid substrates with macroscopic random roughness are considered as a function of the microscopic contact angle of the wetting liquid and its partial pressure in the surrounding gas phase. It is shown that Wenzel prewetting, which has been recently predicted for a rather wide class of roughness profiles derived from Gaussian random

C. Wetterich

In models of emergent gravity the metric arises as the expectation value of some collective field. Usually, many different collective fields with appropriate tensor properties are candidates for a metric. Which collective field describes the &#34;physical geometry&#34;? We resolve this &#34;metric ambiguity&#34; by an investigation of the most general form o

Lihua Bai, Jostein Paulsen

In Bai and Paulsen (SIAM J. Control optim. 48, 2010) the optimal dividend problem under transaction costs was analyzed for a rather general class of diffusion processes. It was divided into several subclasses, and for the majority of subclasses the optimal policy is a simple barrier policy; whenever the process hits an upper barrier $\bar{u}^*$, reduce it to

Paolo Cascini, De-Qi Zhang

We describe a bound on the degree of the generators for some adjoint rings on surfaces and threefolds.

Jungyeon Cho, A. Lazarian, P. Timbie

One of the main challenges for future 21 cm observations is to remove foregrounds which are several orders of magnitude more intense than the HI signal. We propose a new technique for removing foregrounds of the redshifted 21 cm observations. We consider multi-frequency interferometer observations. We assume that the 21 cm signals in different frequency chan

Rajkumar Buyya, Suraj Pandey, Christian Vecchiola

Cloud computing has penetrated the Information Technology industry deep enough to influence major companies to adopt it into their mainstream business. A strong thrust on the use of virtualization technology to realize Infrastructure-as-a-Service (IaaS) has led enterprises to leverage subscription-oriented computing capabilities of public Clouds for hosting

François-Régis Jasnot, Louis-Anne De Vaulchier, Yves Guldner, Gérald Bastard

A strong magnetic field applied along the growth direction of a semiconductor quantum well gives rise to a spectrum of discrete energy states, the Landau levels. By combining quantum engineering of a quantum cascade structure with a static magnetic field, we can selectively inject electrons into the excited Landau level of a quantum well and realize a tunabl

M. Wittkowski, P. H. Hauschildt, B. Arroyo Torres, J. M. Marcaide

We investigate the atmospheric structure and fundamental properties of the red supergiant VY CMa. We obtained near-infrared spectro-interferometric observations of VY CMa with spectral resolutions of 35 and 1500 using the AMBER instrument at the VLTI. The visibility data indicate the presence of molecular layers of water vapor and CO in the extended atmosphe

Xiaoping Zhang

We present phi-meson transverse momentum distribution as well as its elliptic flow (v_{2}) measurements in Au + Au collisions at center-of-mass energy per nucleon pair \sqrt{s_{NN}} = 7.7, 11.5 and 39 GeV with the data taken from STAR experiment at RHIC in the year 2010. We discuss the energy dependence of phi-meson elliptic flow (v_{2}) and central-to-perip

Ferenc Moricz

Let the function $f: \bar{\R}^2_+ \to \C$ be such that $f\in L^1_{\loc} (\bar{\R}^2_+)$. We investigate the convergence behavior of the double integral $$\int^A_0 \int^B_0 f(u,v) du dv \quad {\rm as} \quad A,B \to \infty,\leqno(*)$$ where $A$ and $B$ tend to infinity independently of one another; while using two notions of convergence: that in Pringsheim&#39

Vincent Calvez, Pierre Gabriel

We analyse an optimal control with the following features: the dynamical system is linear, and the dependence upon the control parameter is affine. More precisely we consider $\dot x_α(t) = (G + α(t) F)x_α(t)$, where $G$ and $F$ are $3\times 3$ matrices with some prescribed structure. In the case of constant control $α(t)\equiv α$, we show the existence of a

Stefan Henß, Martin Monperrus, Mira Mezini

Frequently asked questions (FAQs) are a popular way to document software development knowledge. As creating such documents is expensive, this paper presents an approach for automatically extracting FAQs from sources of software development discussion, such as mailing lists and Internet forums, by combining techniques of text mining and natural language proce

Franck Sueur

In this paper we investigate the issue of the inviscid limit for the compressible Navier-Stokes system in an impermeable fixed bounded domain. We consider two kinds of boundary conditions. The first one is the no-slip condition. In this case we extend the famous conditional result obtained by Kato in the homogeneous incompressible case. Kato proved that if t

Yue Guan, Jianfeng Hou, Yingyuan Yang

Proper edge coloring of a graph $G$ is called acyclic if there is no bichromatic cycle in $G$. The acyclic chromatic index of $G$, denoted by $χ&#39;_a(G)$, is the least number of colors $k$ such that $G$ has an acyclic edge $k$-coloring. Basavaraju et al. [Acyclic edge-coloring of planar graphs, SIAM J. Discrete Math. 25 (2) (2011), 463--478] showed that $χ

Jean-Philippe Georget, Baptiste Labrousse

This paper is about an experiment with the goal of testing a primary teacher&#39;s resource. This is the next part of a research presented at EMF2009. This resource must help a teacher to practice a research and proof activity between peers with her pupils even she had never done this before. The paper presents the problems given by this project and describe

Xianglei Zhu

We report on the measurements of Ks, Lambda and Xi spectra at mid-rapidity (|y|<0.5) in the most central (0-5%) Au+Au collisions at \sqrt{s_NN} = 7.7, 11.5 and 39 GeV from the STAR experiment. The extracted yields and the corresponding data from Pb+Pb collisions measured by the NA49 and CERES experiments at SPS are consistent. The Lambda, Anti-Lambda, Xi- an

Xianglei Zhu

We report on the pT dependence of nuclear modification factors ($R_{CP}$) for Ks, Lambda, Xi and the Anti-Lambda/Ks ratios at mid-rapidity from Au+Au collisions at \sqrt{s_{NN}} = 39, 11.5 and 7.7 GeV. At \sqrt{s_{NN}} = 39 GeV, the $R_{CP}$ data shows a baryon/meson separation at intermediate pT and a suppression for Ks for pT up to 4.5 GeV/$c$; the Anti-La

Frank Nielsen

We describe $k$-MLE, a fast and efficient local search algorithm for learning finite statistical mixtures of exponential families such as Gaussian mixture models. Mixture models are traditionally learned using the expectation-maximization (EM) soft clustering technique that monotonically increases the incomplete (expected complete) likelihood. Given prescrib

Bao-Ji Wang, San-Huang Ke

The collective electronic excitation in planar sodium clusters is studied by time-dependent density functional theory calculations. The formation and development of the resonances in photoabsorption spectra are investigated in terms of the shape and size of the 2-dimensional (2-D) systems. The nature of these resonances is revealed by the frequency-resolved

Gabriela Araujo-Pardo, Isabel Hubard, Deborah Oliveros, Egon Schulte

The paper investigates connections between abstract polytopes and properly edge colored graphs. Given any finite n-edge-colored n-regular graph G, we associate to G a simple abstract polytope P_G of rank n, called the colorful polytope of G, with 1-skeleton isomorphic to G. We investigate the interplay between the geometric, combinatorial, or algebraic prope

Xin-Ying Zhu, Xi-Zhen Zhang, Hong-Bo Zhang, De-Qing Kong

Ground-based observation of Interplanetary Scintillation(IPS) is an important approach of monitoring solar wind. A ground-based IPS observation system is newly implemented on 50m radio telescope, Miyun station, National Astronomical Observatories, Chinese Academy of Sciences(NAOC). This observation system is constructed for purpose of observing the solar win

Sayipjamal Dulat, Kai Ma

We reexamine the topological and nonlocal natures of the Aharonov-Casher and scalar Aharonov-Bohm phase effects. The underlying U(1) gauge structure is exhibited explicitly. And the conditions for developing topological Aharonov-Casher and scalar Aharonov-Bohm phases are clarified. We analyse the arguments of M. Peshkin and H. J. Lipkin (Phys. Rev. Lett. 74,

Ali Kebarighotbi, Christos G. Cassandras

We extend the definition of a Stochastic Hybrid Automaton (SHA) to overcome limitations that make it difficult to use for on-line control. Since guard sets do not specify the exact event causing a transition, we introduce a clock structure (borrowed from timed automata), timer states, and guard functions that disambiguate how transitions occur. In the modifi

S. Seo, V. A. Sidorov, H. Lee, D. Jang

The f-electron compound CeAuSb2, which crystallizes in the ZrCuSi2-type tetragonal structure, orders antiferromagnetically between 5 and 6.8 K, where the antiferromagnetic transition temperature T_N depends on the occupancy of the Au site. Here we report the electrical resistivity and heat capacity of a high-quality crystal CeAuSb2 with T_N of 6.8 K, the hig

W. J. Zhang, S. K. He, H. Xiao, G. M. Xue

Superconducting triangular Nb wire networks with high normal-state resistance are fabricated by using a negative tone hydrogen silsesquioxane (HSQ) resist. Robust magnetoresistance oscillations are observed up to high magnetic fields and maintained at low temperatures, due to the eective reduction of wire dimensions. Well-defined dips appear at integral and

Li Huang, Liang Du, Xi Dai

Motivated by the unexplored complexity of the phase diagrams for multi-orbital Hubbard models, a three-band Hubbard model at integer fillings (N=4) with orbital degeneracy lifted partially by crystal field splitting is analyzed systematically in this work. By using single site dynamical mean-field theory and rotationally invariant Gutzwiller approximation, w

J. Brauchart, J. Dick

In this paper we study reproducing kernel Hilbert spaces of arbitrary smoothness on the sphere $\mathbb{S}^d \subset \mathbb{R}^{d+1}$. The reproducing kernel is given by an integral representation using the truncated power function $(\boldsymbol{x} \cdot \boldsymbol{z} - t)_+^{β-1}$ defined on spherical caps centered at $\boldsymbol{z}$ of height $t$, which

Kee-Hoon Kim, Hyun-Bae Jeon, Jong-Seon No, Dong-Joon Shin

In this paper, a new peak-to-average power ratio (PAPR) reduction scheme for orthogonal frequency division multiplexing (OFDM) is proposed based on the selected mapping (SLM) scheme. The proposed SLM scheme generates alternative OFDM signal sequences by cyclically shifting the connections in each subblock at an intermediate stage of inverse fast Fourier tran

Vasilis Syrgkanis

We consider a general class of Bayesian Games where each players utility depends on his type (possibly multidimensional) and on the strategy profile and where players&#39; types are distributed independently. We show that if their full information version for any fixed instance of the type profile is a smooth game then the Price of Anarchy bound implied by t

L. J. S. Sousa, W. T. Cruz, C. A. S. Almeida

This work is devoted to the study of tensor gauge fields on a string-like defect in six dimensions. This model is very successful in localizing fields of various spins only by gravitational interaction. Due to problems of field localization in membrane models we are motivated to investigate if a string-like defect localizes the Kalb-Ramond field. In contrast

Jianke Yang

Bifurcations of solitary waves are classified for the generalized nonlinear Schrödinger equations with arbitrary nonlinearities and external potentials in arbitrary spatial dimensions. Analytical conditions are derived for three major types of solitary wave bifurcations, namely saddle-node bifurcations, pitchfork bifurcations and transcritical bifurcations.

Thorsten Hohage, Frank Werner

We study Newton type methods for inverse problems described by nonlinear operator equations $F(u)=g$ in Banach spaces where the Newton equations $F&#39;(u_n;u_{n+1}-u_n) = g-F(u_n)$ are regularized variationally using a general data misfit functional and a convex regularization term. This generalizes the well-known iteratively regularized Gauss-Newton method

Lawrence C. Andrews, Herbert J. Bernstein

Correct identification of the Bravais lattice of a crystal is an important step in structure solution. Niggli reduction is a commonly used technique. We investigate the boundary polytopes of the Niggli-reduced cone in the six-dimensional space G6 by algebraic analysis and organized random probing of regions near 1- through 8-fold boundary polytope intersecti

Nigel P. Byott, Mark Holland, Yiwei Zhang

We consider the effect on the mixing properties of a piecewise smooth interval map $f$ when its domain is divided into $N$ equal subintervals and $f$ is composed with a permutation of these. The case of the stretch-and-fold map $f(x)=mx \bmod 1$ for integers $m \geq 2$ is examined in detail. We give a combinatorial description of those permutations $σ$ for w

Axel Cortés Cubero, Peter Orland

We examine the effect of quantum longitudinal rescaling of coordinates, on the action of quantum chromodynamics (with quarks) to one loop. We use an aspherical Wilsonian integration (previously applied to the pure Yang-Mills theory and to quantum electrodynamics). Quantum fluctuations produce anomalous powers of the rescaling parameter in the coefficients of

Francisco M. Fernández

We obtain accurate eigenvalues for two recently derived SUSY partner Hamiltonians. We improve the Rayleigh-Ritz variational method proposed by the authors and show how to apply the Riccati-Padé method to those particular partner potentials.

M. Laufer, P. Orland

We find coordinates, the metric tensor, the inverse metric tensor and the Laplace-Beltrami operator for the orbit space of Hamiltonian SU(2) gauge theory on a finite, rectangular lattice. This is done using a complete axial gauge fixing. The Gribov problem can be completely solved, with no remaining gauge ambiguities.

Amrik Sen, Pablo D. Mininni, Duane Rosenberg, Annick pouquet

Rapidly rotating turbulent flow is characterized by the emergence of columnar structures that are representative of quasi-two dimensional behavior of the flow. It is known that when energy is injected into the fluid at an intermediate scale $L_f$, it cascades towards smaller as well as larger scales. In this paper we analyze the flow in the \textit{inverse c

David Renfrew, Alexander Soshnikov

We study the distribution of the outliers in the spectrum of finite rank deformations of Wigner random matrices. We assume that the matrix entries have finite fourth moment and extend the results by Capitaine, Donati-Martin, and Féral for perturbations whose eigenvectors are delocalized.