June 2013 arXiv papers — page 21
Showing 2,001–2,100 of 7,155 papers
P. Nalbach, M. Schechter
Tunneling two-level systems are ubiquitous in amorphous solids, and form a major source of noise in systems such as nano-mechanical oscillators, single electron transistors, and superconducting qubits. Occurance of defect tunneling despite their coupling to phonons is viewed as a hallmark of weak defect-phonon coupling. This is since strong coupling to phono
L. Agozzino, P. Castorina, P. Colangelo
The nucleon structure function $F_2^N$ computed in a holographic framework can be used to describe nuclear deep inelastic scattering effects provided that a rescaling of the $Q^2$ momentum and of the IR hard-wall parameter $z_0$ is made. The ratios $R_A=F_2^A/F_2^N$ can be obtained in terms of a single rescaling parameter $λ_A$ for each nucleus. The resultin
Uniqueness in weighted Lebesgue spaces for a class of fractional parabolic and elliptic equations
math.APFabio Punzo, Enrico Valdinoci
We investigate uniqueness, in suitable weighted Lebesgue spaces, of solutions to a class of fractional parabolic and elliptic equations.
Alexey Antonik, Alexandre Berred, Sergey Malov
Motivated by some problems in genome assembling, we investigate properties of spacings from absolutely continuous distributions. Several results on the asymptotic behavior of the maximal uniform and non-uniform $k$-spacings are presented. Applications of these results to the coverage problem for the prediction stage in genome assembling are also provided.
Micro-joule sub-10-fs VUV pulse generation by MW pump pulse using highly efficient chirped-four-wave mixing in hollow-core photonic crystal fibers
physics.opticsSong-Jin Im
We theoretically study chirped four-wave mixing for VUV pulse generation in hollow-core photonic crystal fibers. We predict the generation of sub-10-fs VUV pulses with energy of up to hundreds of microjoule by broad-band chirped idler pulses at 830 nm and MW pump pulses with narrow-band at 277 nm. MW pump could be desirable to reduce the complexity of the la
Dong Xie, An Min Wang
We analytically obtain the precision bounds of frequency measurements in correlated Markovian and non-Markovian environments by using a variational approach. It is verified that in standard Ramsey spectroscopy setup, the metrological equivalence of product and maximally entangled states persists in maximally correlated Markovian and non-Markovian environment
L. Sun, Q. Wang, H. Zhan
The likelihood function is a crucial element of parameter estimation. In analyses of galaxy overdensities and weak lensing shear, one often approximates the likelihood of the power spectrum with a Gaussian distribution. The posterior probability derived from such a likelihood deviates considerably from the exact posterior on the largest scales probed by any
Huan Zhang, Peter M. Dower
Efficient Riccati equation based techniques for the approximate solution of discrete time linear regulator problems are restricted in their application to problems with quadratic terminal payoffs. Where non-quadratic terminal payoffs are required, these techniques fail due to the attendant non-quadratic value functions involved. In order to compute these non
Nahomi Kan, Koichiro Kobayashi, Kiyoshi Shiraishi
We show that the higher order gravity model proposed by Meissner and Olechowski has a graviton mode, a massive spin-two excitation and no scalar mode in a maximally symmetric spacetime; therefore, by choosing the coefficients, we can construct a Lagrangian for `critical gravity' from higher order terms of curvatures in higher dimensions. We also give a c
Masahiro Hotta, Jiro Matsumoto, Ken Funo
The unitary moving mirror model is one of the best quantum systems for checking the reasoning of the original firewall paradox of AMPS in quantum black holes. Though the late-time part of radiations emitted from the mirror is fully entangled with the early-part, no firewall exists with a deadly, huge average energy flux in this model. This is because high-en
Tyler Sanderson, Clayton Scott
This work addresses two classification problems that fall under the heading of domain adaptation, wherein the distributions of training and testing examples differ. The first problem studied is that of class proportion estimation, which is the problem of estimating the class proportions in an unlabeled testing data set given labeled examples of each class. C
Nicolas Raymond, San Vu Ngoc
This paper is devoted to the classical mechanics and spectral analysis of a pure magnetic Hamiltonian in $\R^2$. It is established that both the dynamics and the semiclassical spectral theory can be treated through a Birkhoff normal form and reduced to the study of a family of one dimensional Hamiltonians. As a corollary, recent results by Helffer-Kordyukov
Ben C. Nolting, Travis M. Hinkelman, Chad E. Brassil, Brigitte Tenhumberg
Many foraging animals find food using composite random search strategies, which consist of intensive and extensive search modes. Models of composite search can generate predictions about how optimal foragers should behave in each search mode, and how they should determine when to switch between search modes. Most of these models assume that foragers use reso
Toshihiko Masuda, Reiji Tomatsu
We will study two kinds of actions of a discrete amenable Kac algebra. The first one is an action whose modular part is normal. We will construct a new invariant which generalizes a characteristic invariant for a discrete group action, and we will present a complete classification. The second is a centrally free action. By constructing a Rohlin tower in an a
Nalini Joshi
In this paper, we present new, unstable solutions, which we call quicksilver solutions, of a $q$-difference Painlevé equation in the limit as the independent variable approaches infinity. The specific equation we consider in this paper is a discrete version of the first Painlevé equation ($q\Pon$), whose phase space (space of initial values) is a rational su
Qian Li, Tao Zhou, Linyuan Lv, Duanbing Chen
Identifying influential spreaders is crucial for understanding and controlling spreading processes on social networks. Via assigning degree-dependent weights onto links associated with the ground node, we proposed a variant to a recent ranking algorithm named LeaderRank [L. Lv et al., PLoS ONE 6 (2011) e21202]. According to the simulations on the standard SI
Toshimasa Ishii, Hirotaka Ono, Yushi Uno
Given a graph $G=(V,E)$ of order $n$ and an $n$-dimensional non-negative vector $d=(d(1),d(2),\ldots,d(n))$, called demand vector, the vector domination (resp., total vector domination) is the problem of finding a minimum $S\subseteq V$ such that every vertex $v$ in $V\setminus S$ (resp., in $V$) has at least $d(v)$ neighbors in $S$. The (total) vector domin
J. Choi, H. Ishitsuka, S. Mima, S. Oguri
In the field of radiowave detection, enlarging the receiver aperture to enhance the amount of light detected is essential for greater scientific achievements. One challenge in using radio transmittable apertures is keeping the detectors cool. This is because transparency to thermal radiation above the radio frequency range increases the thermal load. A techn
L. P. Colatto, A. L. A. Penna
In this paper we construct and study a formulation of a chargeless complex vector matter field in a supersymmetric framework. To this aim we combine two no-chiral scalar superfields in order to take the vector component field to build the chargeless complex vector superpartner where the respective field strength transforms as matter fields by a global $U(1)$
Inertia groups of a toric DM stack, fake weighted projective spaces, and labelled sheared simplices
math.SGRebecca Goldin, Megumi Harada, David Johannsen, Derek Krepski
This paper determines the inertia groups (isotropy groups) of the points of a toric Deligne-Mumford stack [Z/G] (considered over the category of smooth manifolds) that is realized from a quotient construction using a stacky fan or stacky polytope. The computation provides an explicit correspondence between certain geometric and combinatorial data. In particu
Tosiaki Kori, Yuto Imai
Let $H$ be the quaternion algebra. Let $g$ be a complex Lie algebra and let $U(g)$ be the enveloping algebra of $g$. We define a Lie algebra structure on the tensor product space of $H$ and $U(g)$, and obtain the quaternification $g^H$ of $g$. Let $S^3g^H$ be the set of $g^H$-valued smooth mappings over $S^3$. The Lie algebra structure on $S^3g^H$ is induced
Inviscid damping and the asymptotic stability of planar shear flows in the 2D Euler equations
math.APJacob Bedrossian, Nader Masmoudi
We prove asymptotic stability of shear flows close to the planar Couette flow in the 2D inviscid Euler equations on $\Torus \times \Real$. That is, given an initial perturbation of the Couette flow small in a suitable regularity class, specifically Gevrey space of class smaller than 2, the velocity converges strongly in L^2 to a shear flow which is also clos
Yair Caro, Adriana Hansberg, Ryan Pepper
The regular independence number, introduced by Albertson and Boutin in 1990, is the size of a largest set of independent vertices with the same degree. Lower bounds were proven for this invariant, in terms of the order, for trees and planar graphs. In this article, we generalize and extend these results to find lower bounds for the regular $k$-independence n
Steven Hurder, Ana Rechtman
In this work, we study the dynamical properties of Krystyna Kuperberg's aperiodic flows on $3$-manifolds. We introduce the notion of a ``zippered lamination'', and with suitable generic hypotheses, show that the unique minimal set for such a flow is an invariant zippered lamination. We obtain a precise description of the topology and dynamical pr
D. M. Asner, P. C. Bhat, S. Henderson, R. Plunkett
Part-3 of "Project X: Accelerator Reference Design, Physics Opportunities, Broader Impacts". The proposed Project X proton accelerator at Fermilab, with multi-MW beam power and highly versatile beam formatting, will be a unique world-class facility to explore particle physics at the intensity frontier. Concurrently, however, it can also facilitate im
Features of adsorbed radioactive chemical elements and their isotopes distribution in iodine air filters AU-1500 at nuclear power plants
physics.ao-phI. M. Neklyudov, A. N. Dovbnya, N. P. Dikiy, O. P. Ledenyov
The main aim of research is to investigate the physical features of spatial distribution of the adsorbed radioactive chemical elements and their isotopes in the granular filtering medium in the iodine air filters of the type of AU1500 in the forced exhaust ventilation systems at the nuclear power plant. The gamma activation analysis method is applied to accu
Christopher G. Jesudason
Optimization methods have been broadly applied to two classes of objects viz. (i) modeling and description of data and (ii) the determination of the stationary points of functions. Here, a theoretical basis is developed that optimizes an arbitrary number of variables for classes (i) and (ii) by the minimization of a function of a single variable. Algorithms
Luigi Santocanale, Friedrich Wehrung
For a closure space (P,f) with f(\emptyset)=\emptyset, the closures of open subsets of P, called the regular closed subsets, form an ortholattice Reg(P,f), extending the poset Clop(P,f) of all clopen subsets. If (P,f) is a finite convex geometry, then Reg(P,f) is pseudocomplemented. The Dedekind-MacNeille completion of the poset of regions of any central hyp
Peter Hornung
We derive the Euler-Lagrange equation corresponding to a variant of non-Euclidean constrained von Karman theories.
Study of the possibility of eliminating the Gibbs paradox within the framework of classical thermodynamics
physics.hist-phV. Ihnatovych
The formulas for the entropy of ideal gases mixture and the entropy change in mixing of ideal gases on the basis of the third law of thermodynamics were obtained. It is shown that when using these formulas, the Gibbs paradox within the framework of classical thermodynamics does not arise.
Modifying the Entity relationship modelling notation: towards high quality relational databases from better notated ER models
cs.DBDhammika Pieris
The entity relationship modelling using the original ER notation has been applauded providing a natural view of data in conceptual modelling of information systems. However, the current ER to relational model transformation algorithm is known to be insufficient in providing a complete and accurate representation of the ER model undertaken for transformation.
First measurement of the small-scale spatial variability of the rain drop size distribution: Results from a crucial experiment and maximum entropy modeling
physics.ao-phRamiro Checa-Garcia
The main challenges of measuring precipitation are related to the spatio-temporal variability of the drop-size distribution, to the uncertainties that condition the modeling of that distribution, and to the instrumental errors present in the in situ estimations. This PhD dissertation proposes advances in all these questions. The relevance of the spatial vari
David Leen, Eric Shea-Brown
The collective dynamics of neural populations are often characterized in terms of correlations in the spike activity of different neurons. Open questions surround the basic nature of these correlations. In particular, what leads to higher-order correlations -- correlations in the population activity that extend beyond those expected from cell pairs? Here, we
Hermano Velten
We discuss bulk viscous cosmological models. Since the bulk viscous pressure is negative, viable viscous cosmological scenarios with late time accelerated expansion can in principle be constructed. After discussing some alternative models based on bulk viscous effects we will focus on a model very similar to the standard $Λ$CDM. We argue that a $Λ${\rm v}CDM
Anton Ibragimov
In this paper, we extend the G-expectation theory to infinite dimensions. Such notions as a covariation set of G-normal distributed random variables, viscosity solution, a stochastic integral driven by G-Brownian motion are introduced and described in the given infinite dimensional case. We also give a probabilistic representation of the unique viscosity sol
A near-infrared variability campaign of TMR-1: New light on the nature of the candidate protoplanet TMR-1C
astro-ph.SRB. Riaz, E. L. Martin, M. G. Petr-Gotzens, J. -L. Monin
(abridged) We present a near-infrared (NIR) photometric variability study of the candidate protoplanet, TMR-1C, located at a separation of about 10" (~1000 AU) from the Class I protobinary TMR-1AB in the Taurus molecular cloud. Our campaign was conducted between October, 2011, and January, 2012. We were able to obtain 44 epochs of observations in each of
F. Pezzoli, F. Isa, G. Isella, C. V. Falub
Germanium and silicon-germanium alloys have found entry into Si technology thanks to their compatibility with Si processing and their ability to tailor electronic properties by strain and band-gap engineering. Germanium's potential to extend Si functionalities, as exemplified by lasing action of strained-Ge on Si substrates, has brought the material back
D. D. Khalyavin, D. T. Adroja, P. Manuel, J. Kawabata
The effect of Ir substitution for Os in CeOs2Al10, with an unusually high Neel temperature of T~28.5K, has been studied by high-resolution neutron diffraction and magnetization measurements. A small amount of Ir (~ 8%) results in a pronounced change of the magnetic structure of the Ce-sublattice. The new magnetic ground state is controlled by the single ion
Christian Staudt, Andrea Schumm, Henning Meyerhenke, Robert Görke
Collaboration networks arise when we map the connections between scientists which are formed through joint publications. These networks thus display the social structure of academia, and also allow conclusions about the structure of scientific knowledge. Using the computer science publication database DBLP, we compile relations between authors and publicatio
P. Tzanavaris, T. Fragos, M. Tremmel, L. Jenkins
We present the largest-scale comparison to date between observed extragalactic X-ray binary (XRB) populations and theoretical models of their production. We construct observational X-ray luminosity functions (oXLFs) using Chandra observations of 12 late-type galaxies from the Spitzer Infrared Nearby Galaxy Survey (SINGS). For each galaxy, we obtain theoretic
Nikolaj Bjorner, Ken McMillan, Andrey Rybalchenko
We report on work in progress on automatic procedures for proving properties of programs written in higher-order functional languages. Our approach encodes higher-order programs directly as first-order SMT problems over Horn clauses. It is straight-forward to reduce Hoare-style verification of first-order programs into satisfiability of Horn clauses. The pre
Discriminative Training: Learning to Describe Video with Sentences, from Video Described with Sentences
cs.CVHaonan Yu, Jeffrey Mark Siskind
We present a method for learning word meanings from complex and realistic video clips by discriminatively training (DT) positive sentential labels against negative ones, and then use the trained word models to generate sentential descriptions for new video. This new work is inspired by recent work which adopts a maximum likelihood (ML) framework to address t
Multiscale Topological Properties Of Functional Brain Networks During Motor Imagery After Stroke
q-bio.NCFabrizio De Vico Fallani, Floriana Pichiorri, Giovanni Morone, Marco Molinari
In recent years, network analyses have been used to evaluate brain reorganization following stroke. However, many studies have often focused on single topological scales, leading to an incomplete model of how focal brain lesions affect multiple network properties simultaneously and how changes on smaller scales influence those on larger scales. In an EEG-bas
L. Amati, J. -L. Atteia, L. Balazs, S. Basa
Gamma-Ray Bursts (GRBs) are the most powerful cosmic explosions since the Big Bang, and thus act as signposts throughout the distant Universe. Over the last 2 decades, these ultra-luminous cosmological explosions have been transformed from a mere curiosity to essential tools for the study of high-redshift stars and galaxies, early structure formation and the
Fuzzy games with a countable space of actions and applications to systems of generalized quasi-variational inequalities
math.OCMonica Patriche
In this paper, we introduce an abstract fuzzy economy (generalized fuzzy game) model with a countable space of actions and we study the existence of the fuzzy equilibrium. As applications, two types of results are obtained. The first ones concern the existence of the solutions for systems of generalized quasi-variational inequalities with random fuzzy mappin
Edward Barbeau, Samer Seraj
Inspired by the fact that the sum of the cubes of the first $n$ naturals is equal to the square of their sum, we explore, for each $n$, the Diophantine equation representing all non-trivial sets of $n$ integers with this property. We find definite answers to the standard question of infinitude of the solutions as well as several other surprising results.
Local Ionization Dynamics Traced by Photoassisted Scanning Tunneling Microscopy: A Theoretical Approach
cond-mat.mes-hallM. Schueler, Y. Pavlyukh, J. Berakdar
For tracing the spatiotemporal evolution of electronic systems, we suggest and analyze theoretically a setup that exploits the excellent spatial resolution based on scanning tunneling microscopy techniques combined with the temporal resolution of femtosecond pump-probe photoelectron spectroscopy. As an example, we consider the laser-induced, local vibrationa
A determination of the space density and birth rate of hydrogen-line (DA) white dwarfs in the Galactic Plane, based on the UVEX survey
astro-ph.SRKars Verbeek, Paul J. Groot, Gijs Nelemans, Simone Scaringi
We present a determination of the average space density and birth rate of hydrogen-line (DA) white dwarfs within a radius of 1 kpc around the Sun, based on an observational sample of 360 candidate white dwarfs with g<19.5 and (g-r)<0.4, selected from the UV-excess Survey of the Northern Galactic Plane (UVEX), in combination with a theoretical white dwarf pop
Rafael de la Madrid
We present a theoretical analysis of quantum decay in which the survival probability is replaced by a decay rate that is equal to the absolute value squared of the wave function in the time representation. The wave function in the time representation is simply the Fourier transform of the wave function in the energy representation, and it is also the probabi
Peter Kinnaird
As technologies are developed and constructed, designers may or may not be aware that they are embedding politics and values into their artifacts. Computer scientists operate and advance their field by building layers of abstraction into software and hardware to reduce the complexity of interfaces, making the artifacts they create zuhanden for others in part
Duncan Forbes, Vincenzo Pota, Christopher Usher, Jay Strader
It is not understood whether long-lived star clusters possess a continuous range of sizes and masses (and hence densities), or if rather, they should be considered as distinct types with different origins. Utilizing the Hubble Space Telescope (HST) to measure sizes, and long exposures on the Keck 10m telescope to obtain distances, we have discovered the firs
Rebecca G. Martin, Mario Livio
We examine the evolution of the snow line in a protoplanetary disc that contains a dead zone (a region of zero or low turbulence). The snow line is within a self-gravitating part of the dead zone, and we obtain a fully analytic solution for its radius. Our formula could prove useful for future observational attempts to characterise the demographics of planet
Rebecca G. Martin, Philip J. Armitage, Richard D. Alexander
Circumbinary planets have been observed at orbital radii where binary perturbations may have significant effects on the gas disk structure, on planetesimal velocity dispersion, and on the coupling between turbulence and planetesimals. Here, we note that the impact of all of these effects on planet formation is qualitatively altered if the circumbinary disk s
Galaxy halo truncation and Giant Arc Surface Brightness Reconstruction in the Cluster MACSJ1206.2-0847
astro-ph.COThomas Eichner, Stella Seitz, Sherry H. Suyu, Aleksi Halkola
In this work we analyze the mass distribution of MACSJ1206.2-0847, especially focusing on the halo properties of its cluster members. The cluster appears relaxed in its X-ray emission, but has significant amounts of intracluster light which is not centrally concentrated, suggesting that galaxy-scale interactions are still ongoing despite the overall relaxed
Lauren Corlies, Kathryn V. Johnston, Jason Tumlinson, Greg Bryan
Recent observations suggest that abundance pattern differences exist between low metallicity stars in the Milky Way stellar halo and those in the dwarf satellite galaxies. This paper takes a first look at what role the early environment for pre-galactic star formation might have played in shaping these stellar populations. In particular, we consider whether
Hsin-Yi Shih, Alan Stockton, Lisa Kewley
Massive outflows are known to exist, in the form of extended emission-line regions (EELRs), around about one-third of powerful FR II radio sources. We investigate the origin of these EELRs by studying the emission-line regions around compact-steep-spectrum (CSS) radio galaxies that are younger (10$^3$ to 10$^5$ years old) versions of the FR II radio galaxies
How can one detect the rotation of the Earth "around the Moon"? Part 3. With a simple pendulum
physics.class-phMarcel Betrisey, Bertrand M. Roehner
The attraction of the Moon on objects at the surface of the Earth gives rise to a so-called tidal force which is of the order of 1/10,000,000 times the gravitational force of the Earth. For instance, when the Moon is located between the Earth and the Sun (new moon) the distance from a given terrestrial location to the Moon is shorter at noon than at midnight
M. Sich, F. Fras, J. K. Chana, M. S. Skolnick
We report on the spin properties of bright polariton solitons supported by an external pump to compensate losses. We observe robust circularly polarised solitons when a circularly polarised pump is applied, a result attributed to phase synchronisation between nondegenerate TE and TM polarised polariton modes at high momenta. For the case of a linearly polari
F. Manghi
We present an extension of Cluster Perturbation Theory to include many body correlations associated to local e-e repulsion in real materials. We show that this approach can describe the physics of complex correlated materials where different atomic species and different orbitals coexist. The prototypical case of MnO is considered.
Local Electron Beam Excitation and Substrate Effect on the Plasmonic Response of Single Gold Nanostars
cond-mat.mes-hallPabitra Das, Abhitosh Kedia, Pandian Senthil Kumar, Nicolas Large
We performed Cathodoluminescence (CL) spectroscopy and imaging in a high resolution scanning electron microscope to locally and selectively excite and investigate the plasmonic property of a multibranched gold nanostar on silicon substrate. This method allows us to map the local density of optical states from the nanostar with a spatial resolution down to a
Shuang Tian, Yonghui Li, Mahyar Shirvanimoghaddam, Branka Vucetic
In this paper, we propose a physical-layer rateless code for wireless channels. A novel rateless encoding scheme is developed to overcome the high error floor problem caused by the low-density generator matrix (LDGM)-like encoding scheme in conventional rateless codes. This is achieved by providing each symbol with approximately equal protection in the encod
Thiago Castilho de Mello, Lucio Centrone
The algebra of $n\times n$ matrices over a field $F$ has a natural $\mathbb{Z}_n$-grading. Its graded identities have been described by Vasilovsky who extended a previous work of Di Vincenzo for the algebra of $2\times 2$ matrices. In this paper we study the graded identities of block-triangular matrices with the grading inherited by the grading of $M_n(F)$.
Martin Nöllenburg, Roman Prutkin
Greedy embedding (or drawing) is a simple and efficient strategy to route messages in wireless sensor networks. For each source-destination pair of nodes s, t in a greedy embedding there is always a neighbor u of s that is closer to t according to some distance metric. The existence of greedy embeddings in the Euclidean plane R^2 is known for certain graph c
G. Li, Z. Xiang, F. Yu, T. Asaba
In Kondo insulator samarium hexaboride SmB$_6$, strong correlation and band hybridization lead to an insulating gap and a diverging resistance at low temperature. The resistance divergence ends at about 5 Kelvin, a behavior recently demonstrated to arise from the surface conductance. However, questions remain whether and where a topological surface state exi
Jinfeng Liao
A number of recent progresses in the study of strong field effects in heavy ion collisions are discussed here: 1) the Chiral Magnetic Wave (CMW) and its experimental manifestation via splitting of positive/negative pions' elliptic flow; 2) the event-by-event azimuthal fluctuations of strong EM fields and its correlations with matter geometry; 3) a new me
Modification to Darcy model for high pressure and high velocity applications and associated mixed finite element formulations
math.NAJ. Chang, K. B. Nakshatrala
The Darcy model is based on a plethora of assumptions. One of the most important assumptions is that the Darcy model assumes the drag coefficient to be constant. However, there is irrefutable experimental evidence that viscosities of organic liquids and carbon-dioxide depend on the pressure. Experiments have also shown that the drag varies nonlinearly with r
Andreas Tolk, Saikou Y. Diallo, Jose J. Padilla, Ross Gore
Epistemology is the branch of philosophy that deals with gaining knowledge. It is closely related to ontology. The branch that deals with questions like "What is real?" and "What do we know?" as it provides these components. When using modeling and simulation, we usually imply that we are doing so to either apply knowledge, in particular when
Brynmor Haskell, Danai Antonopoulou
Pulsar glitches are sudden increases in the spin frequency of an otherwise steadily spinning down neutron star. These events are thought to represent a direct probe of the dynamics of the superfluid interior of the star. However glitches can differ significantly from one another, not only in size and frequency, but also in the post-glitch response of the sta
Implications of Charge Ordering in the High Tc Cuprate Superconductors in the Far-infrared Spectroscopy
cond-mat.supr-conY. H. Kim, P. H. Hor
We addressed the issue of the absence of the far-infrared signatures pertaining to charge ordering in the published far-infrared reflectivity data of La2-xSrxCuO4 single crystals while other experimental probes unravel that charge ordering is a hallmark of the superconducting cuprates. Through direct comparison of the far-infrared data reported by various gr
Contradictory entropic joint uncertainty relations for complementary observables in two-level systems
quant-phAlfredo Luis
We show that different entropic measures of fluctuations lead to contradictory uncertainty relations for two complementary observables. We apply Tsallis and Rényi entropies to the joint distribution emerging from a noisy simultaneous measurement of both observables as well as to the product of their individual statistics, either intrinsic or of operational o
Gurpreet Singh Saini, Priyanka Dubey, Md Tanzilur Rahman
Wireless Networks are most appealing in terms of deployment over a wide range of applications. The key areas are disaster management, industrial unit automation and battlefield surveillance. The paper presents a study over inter-operability of MANET (Mobile Ad-Hoc Network) protocols i.e DSDV, OLSR, ZRP, AODV over WSN (Wireless Sensor Network) [10]. The revie
Eugenio Bianchi, Hal M. Haggard, Carlo Rovelli
We show that Oeckl's boundary formalism incorporates quantum statistical mechanics naturally, and we formulate general-covariant quantum statistical mechanics in this language. We illustrate the formalism by showing how it accounts for the Unruh effect. We observe that the distinction between pure and mixed states weakens in the general covariant context
Daniel Uken, Alessandro Sergi, Francesco Petruccione
We study a number of filtering schemes for the reduction of the statistical error in non-adiabatic calculations by means of the quantum-classical Liouville equation. In particular, we focus on a scheme based on setting a threshold value on the sampling weights, so that when the threshold is overcome the value of the weight is reset, and on another approach w
Is the Sample Good Enough? Comparing Data from Twitter's Streaming API with Twitter's Firehose
cs.SIFred Morstatter, Jürgen Pfeffer, Huan Liu, Kathleen M. Carley
Twitter is a social media giant famous for the exchange of short, 140-character messages called "tweets". In the scientific community, the microblogging site is known for openness in sharing its data. It provides a glance into its millions of users and billions of tweets through a "Streaming API" which provides a sample of all tweets matching
Edward B. Baskerville, Trevor Bedford, Robert C. Reiner, Mercedes Pascual
We describe an approach for identifying groups of dynamically similar locations in spatial time-series data based on a simple Markov transition model. We give maximum-likelihood, empirical Bayes, and fully Bayesian formulations of the model, and describe exhaustive, greedy, and MCMC-based inference methods. The approach has been employed successfully in seve
Y. Baryshnikov, V. Blumen, K. Kim, V. Zharnitsky
A system of two masses connected with a weightless rod (called dumbbell in this paper) interacting with a flat boundary is considered. The sharp bound on the number of collisions with the boundary is found using billiard techniques. In case, the ratio of masses is large and the dumbbell rotates fast, an adiabatic invariant is obtained.
C. Beck, R. Rezaei, K. G. Puschmann
We estimate the formation height range contributing to broad-band and narrow-band filter imaging data in Ca II H to investigate whether spicules can be detected in such observations at the centre of the solar disc. We apply spectral filters of FWHMs from 0.03 nm to 1 nm to observed Ca line profiles to simulate Ca imaging data. We estimate the relative intens
Magnetic ordering in GdNi2B2C revisited by resonant x-ray scattering: evidence for the double-q model
cond-mat.mtrl-sciP. S. Normile, M. Rotter, C. Detlefs, J. Jensen
Recent theoretical efforts aimed at understanding the nature of antiferromagnetic ordering in GdNi2B2C predicted double-q ordering. Here we employ resonant elastic x-ray scattering to test this theory against the formerly proposed, single-q ordering scenario. Our study reveals a satellite reflection associated with a mixed-order component propagation wave ve
Caroline E. Alexander, Robert W. Walsh, Stephane Regnier, Jonathan Cirtain
Plasma flows within prominences/filaments have been observed for many years and hold valuable clues concerning the mass and energy balance within these structures. Previous observations of these flows primarily come from H-alpha and cool EUV lines (e.g., 304A) where estimates of the size of the prominence threads has been limited by the resolution of the ava
Charles H. Conley, Jeannette M. Larsen
Consider the spaces of pseudodifferential operators between tensor density modules over the line as modules of the Lie algebra of vector fields on the line. We compute the equivalence classes of various subquotients of these modules. There is a 2-parameter family of subquotients with any given Jordan-Holder composition series. In the critical case of subquot
M. Otulakowska-Hypka, J. Mikołajewska, P. A. Whitelock
We present new estimates of the basic stellar parameters of the non-eruptive, eclipsing symbiotic system, RW Hydrae. A set of photometric and spectroscopic data was used to model this object simultaneously from the light and radial velocity curves. With new spectroscopic data we were able to improve previous results known from the literature and derive physi
Exchange interactions and frustrated magnetism in single-side hydrogenated and fluorinated graphene
cond-mat.mes-hallA. N. Rudenko, F. J. Keil, M. I. Katsnelson, A. I. Lichtenstein
Magnetism in single-side hydrogenated (C$_2$H) and fluorinated (C$_2$F) graphene is analyzed in terms of the Heisenberg model with parameters determined from first principles. We predict a frustrated ground state for both systems, which means the instability of collinear spin structures and sheds light on the absence of a conventional magnetic ordering in de
M. Otulakowska-Hypka, A. Olech
We present observational evidence that supercycle lengths of the most active SU UMa-type stars are increasing during the past decades. We analysed a large number of photometric measurements from available archives and found that this effect is generic for this class of stars, independently of their evolutionary status. This finding is in agreement with previ
E. Lhotel, V. Simonet, J. Ortloff, B. Canals
We report on the magnetic properties of four isomorphous compounds of a family of quinternary oxalates down to 60 mK. In all these materials, the magnetic FeII ions with a strong magneto-crystalline anisotropy form a distorted kagome lattice, topologically equivalent to a perfect kagome one if nearest-neighbor interactions only are considered. All the compou
Hot-spot model for accretion disc variability as random process - II. Mathematics of the power-spectrum break frequency
astro-ph.HETomas Pechacek, Rene W. Goosmann, Vladimir Karas, Bozena Czerny
We study some general properties of accretion disc variability in the context of stationary random processes. In particular, we are interested in mathematical constraints that can be imposed on the functional form of the Fourier power-spectrum density (PSD) that exhibits a multiply broken shape and several local maxima. We develop a methodology for determini
Bertrand M. Roehner
The accounts of medical trials provide very detailed information about the patients' health conditions. In contrast, only minimal data are usually given about demographic factors. Yet, some of these factors can have a notable impact on the overall death rate, thereby changing the outcome and conclusions of the trial. This paper focuses on two of these va
P. Fraundorf
A small number of (perhaps only 6) broken-symmetries, marked by the edges of a hierarchical series of physical {\em subsystem-types}, underlie the delicate correlation-based complexity of life on our planet's surface. Order-parameters associated with these broken symmetries might in the future help us broaden our definitions of community health. For inst
Crystal, magnetic, and electronic structures, and properties of new BaMnPnF (Pn = As, Sb, Bi)
cond-mat.str-elBayrammurad Saparov, David J. Singh, V. Ovidiu Garlea, Athena S. Sefat
New fluoropnictides BaMnPnF with Pn = As, Sb, Bi, are synthesized by stoichiometric reaction of elements with BaF\_2. The compounds crystallize in the tetragonal P4/nmm (No. 129, Z = 2) space group, with the ZrCuSiAs-type structure, as indicated by single crystal and powder X-ray diffraction results. Electrical resistivity results indicate that Pn = As, Sb,
Jonathan B. Balewski, Alexander T. Krupp, Anita Gaj, David Peter
The coupling of electrons to matter is at the heart of our understanding of material properties such as electrical conductivity. One of the most intriguing effects is that electron-phonon coupling can lead to the formation of a Cooper pair out of two repelling electrons, the basis for BCS superconductivity. Here we study the interaction of a single localized
Lei Wang, Yijuan Xu, Zengru Di, Bertrand M. Roehner
Biologists have found that the death rate of cells in culture depends upon their spatial density. Permanent "Stay alive" signals from their neighbours seem to prevent them from dying. In a previous paper (Wang et al. 2013) we gave evidence for a density effect for ants. In this paper we examine whether there is a similar effect in human demography. W
Julianne I. Moses, Michael R. Line, Channon Visscher, Molly R. Richardson
Neptune-sized extrasolar planets that orbit relatively close to their host stars -- often called "hot Neptunes" -- are common within the known population of exoplanets and planetary candidates. Similar to our own Uranus and Neptune, inefficient accretion of nebular gas is expected produce hot Neptunes whose masses are dominated by elements heavier th
Martin Stynes
Convection-diffusion problems arise in the modelling of many physical processes. Their typical solutions exhibit boundary and/or interior layers. Despite the linear nature of the differential operator, these problems pose still-unanswered questions to the numerical analyst. This talk will give a selective overview of numerical methods for the solution of con
Wafaa Tawfik Abdel-moneim, Mohamed Hashem Abdel-Aziz, Mohamed Monier Hassan
The Clinical E-Science Framework (CLEF) project was used to extract important information from medical texts by building a system for the purpose of clinical research, evidence-based healthcare and genotype-meets-phenotype informatics. The system is divided into two parts, one part concerns with the identification of relationships between clinically importan
A. Zabrodin
Under certain reality conditions, a general solution to the dispersionless Toda lattice hierarchy describes deformations of simply-connected plane domains with a smooth boundary. The solution depends on an arbitrary (real positive) function of two variables which plays the role of a density or a conformal metric in the plane. We consider in detail the import
Peter Hegarty, Anders Martinsson, Dmitry Zhelezov
The classical multi-agent rendezvous problem asks for a deterministic algorithm by which $n$ points scattered in a plane can move about at constant speed and merge at a single point, assuming each point can use only the locations of the others it sees when making decisions and that the visibility graph as a whole is connected. In time complexity analyses of
P. Astone, M. Bassan, E. Coccia, S. D'Antonio
The gravitational wave resonant detectors can be used as detectors of quark nuggets, like nuclearites (nuclear matter with a strange quark). This search has been carried out using data from two 2350 Kg, 2 K cooled, aluminum bar detectors: NAUTILUS, located in Frascati (Italy), and EXPLORER, that was located in CERN Geneva (CH). Both antennas are equipped wit
Robert C. Forrey
Astrophysical models of primordial star formation require rate constants for three-body recombination as input. The current status of these rates for H2 due to collisions with H is far from satisfactory, with published rate constants showing orders of magnitude disagreement at the temperatures relevant for H2 formation in primordial gas. This letter presents
Cristina C. Popescu
This is one chapter of the summary paper of the IAU Special Session SpS8 "Calibration of star-formation rate measurements across the electromagnetic spectrum", Beijing, China, August 2012.
Galina Sherman, David Menachof, Peer-Olaf Siebers, Uwe Aickelin
We introduce a simulation model of the port of Calais with a focus on the operation of immigration controls. Our aim is to compare the cost and benefits of different screening policies. Methodologically, we are trying to understand the limits of discrete event simulation of rare events. When will they become 'too rare' for simulation to give meaningf
Georges Habib, Luigi Vezzoni
We study Riemannian foliations whose transverse Levi-Civita connection $\nabla$ has special holonomy. In particular, we focus on the case where $Hol(\nabla)$ is contained either in SU(n) or in Sp(n). We prove a Weitzenbock formula involving complex basic forms on Kähler foliations and we apply this formula for pointing out some properties of transverse Calab