April 2010 arXiv papers — page 12

Eric V. Linder

One of the great endeavors of the past decade has been the evaluation of different observational techniques for measuring dark energy properties and of theoretical techniques for constraining models of cosmic acceleration given cosmological data. This chapter reviews a few of the key developments, promises, and cautions for revealing dark energy. We also pre

Evgenya L. Shkolnik, Leslie Hebb, Michael C. Liu, I. Neill Reid

As part of our search for young M dwarfs within 25 pc, we acquired high-resolution spectra of 185 low-mass stars compiled by the NStars project that have strong X-ray emission. By cross-correlating these spectra with radial velocity standard stars, we are sensitive to finding multi-lined spectroscopic binaries. We find a low-mass spectroscopic binary fractio

Hernán Piragua, Patricio S. Letelier

The lambda-phi4 kink is linearly and topologically stable. We study how extra energy perturbations are dissipated beyond the linear regime. We found that depending on the width, amplitude and energy of a Gaussian perturbation different scenarios are possible: radiation, oscillons creation, kink anti-kink pairs production and shock waves.

Jerome Gaillard, Dario Martelli, Carlos Nunez, Ioannis Papadimitriou

We discuss a simple transformation that allows to generate SU(3) structure solutions of Type IIB supergravity with RR fluxes, starting from non-Kahler solutions of Type I supergravity. The method may be applied also in the presence of supersymmetric source branes. We apply this transformation to a solution describing fivebranes wrapped on the two-sphere of t

V. Firpo, G. Bosch, G. F. Hägele, N. Morrell

We present new results from our search for Giant H\,{\sc ii} Regions in galaxies visible from the southern hemisphere. In this work we study two galaxies: NGC\,7479 and NGC\,6070. Using high-resolution spectra, obtained with different instruments at Las Campanas Observatory, we are able to resolve the emission-line profile widths and determine the intrinsic

Kyoungchul Kong, Seong Chan Park, Thomas G. Rizzo

Split-UED allows for the possibility that the lowest lying KK excitations of the Standard Model fermions can be much lighter than the corresponding gauge or Higgs KK states. This can happen provided the fermion bulk masses are chosen to be large, in units of the inverse compactification radius, 1/R, and negative. In this setup, all of the other KK states wou

Franco Rigato, Samanta Piano, Michael Foerster, Filippo Giubileo

We have performed point contact spectroscopy measurements on a sample constituted by a metallic ferromagnetic oxide (SrRuO_3) bottom electrode and a tunnel ferrimagnetic (CoFe_2O_4) barrier. Andreev reflection is observed across the tunnel barrier. From the comparison of Andreev reflection in SrRuO3 and across the CoFe_2O_4 barrier we infer that the ferrimag

Jacob Linder, Annica M. Black-Schaffer, Asle Sudbø

We study the interplay between proximity-induced superconductivity and ferromagnetism in graphene by self-consistently solving the Bogoliubov-de Gennes equations on the honeycomb lattice. We find that a strong triplet proximity effect is generated in graphene, leading to odd-frequency pairing correlations. These odd-frequency correlations are clearly manifes

Aaron A. Dutton, Charlie Conroy, Frank C. van den Bosch, Francisco Prada

Using estimates of dark halo masses from satellite kinematics, weak gravitational lensing, and halo abundance matching, combined with the Tully-Fisher and Faber-Jackson relations, we derive the mean relation between the optical, V_opt, and virial, V_200, circular velocities of early- and late-type galaxies at redshift z~0. For late-type galaxies V_opt ~ V_20

Andreas Koch, Patrick Côté

Context: Chemical element abundances for distant Galactic globular clusters (GCs) hold important clues to the origin of the Milky Way halo and its substructures. Aims: We study the chemical composition of red giant stars in Pal 4 - one of the most remote GCs in the Milky Way - and compare our abundance measurements to those for both low surface brightness dw

Akitoshi Kawamura

In answer to Ko's question raised in 1983, we show that an initial value problem given by a polynomial-time computable, Lipschitz continuous function can have a polynomial-space complete solution. The key insight is simple: the Lipschitz condition means that the feedback in the differential equation is weak. We define a class of polynomial-space computat

Johan Sjöström, Johan Mattsson, Rikard Bergman, Erik Johansson

The dielectric relaxation of water in glassy aqueous binary mixtures exhibits an Arrhenius behaviour with a nearly universal activation energy. We here demonstrate that its characteristic relaxation time follows a remarkably general functional dependence on the weight fraction of water for a wide range of molecular systems.

Lamia Chaari, Rim Ayadi, Lotfi Kamoun

This paper proposes, a hardware implementation of Wireless Mesh Networks (WMN) medium Access Controller (MAC) layer transmitter. In the literature a lot of works are focused on WMN routing protocol as well as performance analysis and software integration of WMN units, however few works deals with WMN hardware implementation. In this field our contribution is

Ioannis Bouras, Etele Molnár, Harri Niemi, Zhe Xu

To investigate the formation and the propagation of relativistic shock waves in viscous gluon matter we solve the relativistic Riemann problem using a microscopic parton cascade. We demonstrate the transition from ideal to viscous shock waves by varying the shear viscosity to entropy density ratio $η/s$. Furthermore we compare our results with those obtained

Vitthal J. Gond, Aditya Goel

The rapid development of telecommunication networks is driven by user demands for new applications and advances in technologies. The explosive growth of the internet traffic is due to its use for collecting the information, communication, multimedia application, entertainment, etc. These applications are imposing a tremendous demand for bandwidth capacity on

Md. Shamim Reza, Md. Maruf Hossain, Satya Prasad Majumder

This paper presents a new analytical model for calculating burst loss rate (BLR) in a slotted optical burst switched network. The analytical result leads to a framework which provides guidelines for optical burst switched networks. Wavelength converter is used for burst contention resolution. The effect of several design parameters such as burst arrival prob

Heni Kaaniche, Farouk Kamoun

Mobility prediction allows estimating the stability of paths in a mobile wireless Ad Hoc networks. Identifying stable paths helps to improve routing by reducing the overhead and the number of connection interruptions. In this paper, we introduce a neural network based method for mobility prediction in Ad Hoc networks. This method consists of a multi-layer an

Robert Wille, Mehdi Saeedi, Rolf Drechsler

Many synthesis approaches for reversible and quantum logic have been proposed so far. However, most of them generate circuits with respect to simple metrics, i.e. gate count or quantum cost. On the other hand, to physically realize reversible and quantum hardware, additional constraints exist. In this paper, we describe cost metrics beyond gate count and qua

Nader Haghighipour, Steven S. Vogt, R. Paul Butler, Eugenio J. Rivera

Precision radial velocities from Keck/HIRES reveal a Saturn-mass planet orbiting the nearby M4V star HIP 57050. The planet has a minimum mass of 0.3 Jupiter-mass, an orbital period of 41.4 days, and an orbital eccentricity of 0.31. V-band photometry reveals a clear stellar rotation signature of the host star with a period of 98 days, well separated from the

Yuji Kodama

The main purpose of the paper is to provide a survey of our recent studies on soliton solutions of the Kadomtsev-Petviashvili (KP) equation. The classification is based on the far-field patterns of the solutions which consist of a finite number of line-solitons. Each soliton solution is then defined by a point of the totally non-negative Grassmann variety wh

Abdelati Malek Amel, Ben Abdelali Abdessalem, Mtibaa Abdellatif

This paper focus on the study of the motion activity descriptor for shot boundary detection in video sequences. We interest in the validation of this descriptor in the aim of its real time implementation with reasonable high performances in shot boundary detection. The motion activity information is extracted in uncompressed domain based on adaptive rood pat

C. E. M. Batista, J. C. Fabris, M. Hamani Daouda

The Rastall's theory is a modification of the General Relativity theory leading to a different expression for the conservation law in the matter sector compared with the usual one. It has been argued recently that such a theory may have applications to the dark energy problem, since a pressureless fluid may lead to an accelerated universe. In the present

R. Smith, J. I. Davies, A. H. Nelson

A new harassment model is presented that models the complex, and dynamical tidal field of a Virgo like galaxy cluster. The model is applied to small, late-type dwarf disc galaxies (of substantially lower mass than in previous harassment simulations) as they infall into the cluster from the outskirts. These dwarf galaxies are only mildly affected by high spee

Atri Rudra, Steve Uurtamo

Motivated by applications in storage systems and property testing, we study data stream algorithms for local testing and tolerant testing of codes. Ideally, we would like to know whether there exist asymptotically good codes that can be local/tolerant tested with one-pass, poly-log space data stream algorithms. We show that for the error detection problem (a

Lamia Chaari, Lotfi Kamoun

Wireless sensors networks performance are strictly related to the medium access mechanism. An effective one, require non-conventional paradigms for protocol design due to several constraints. An adequate equilibrium between communication improvement and data processing capabilities must be accomplished. To achieve low power operation, several MAC protocols a

Gerhard Groessing, Siegfried Fussy, Johannes Mesa Pascasio, Herbert Schwabl

Based on the modelling of quantum systems with the aid of (classical) non-equilibrium thermodynamics, both the emergence and the collapse of the superposition principle are understood within one and the same framework. Both are shown to depend in crucial ways on whether or not an average orthogonality is maintained between reversible Schroedinger dynamics an

G. M. M. Bashir, M. J. Hossain, M. R. Karim

Computer Mediated Courseware (CMC) has been developed so far for individual courses considering single or multiple text books. A group of courseware can be developed by using multiple text books and in this case, it is a requirement to cluster the contents of different books to form a generalized clustered content. No work has been found to develop coursewar

Saeed Tavakoli, Mahdieh Zeinadini, Shahram Mohanna

Determination of design parameters based on electromagnetic simulations of microwave circuits is an iterative and often time-consuming procedure. Space mapping is a powerful technique to optimize such complex models by efficiently substituting accurate but expensive electromagnetic models, fine models, with fast and approximate models, coarse models. In this

Jiuhou Lei, Jeffrey P. Thayer, Wenbin Wang, Robert L. McPherron

The solar minimum of 2008 was exceptionally quiet, with sunspot numbers at their lowest in 75 years. During this unique solar minimum epoch, however, solar wind high - speed streams emanating from near-equatorial coronal holes occurred frequently and were the primary contributor to the recurrent geomagnetic activity at Earth. These conditions enabled the iso

Philip Z. Maymin

Representative investors whose behaviour is modelled by a deterministic finite automaton generate complexity both in the time series of each asset and in the cross-sectional correlation when the rule governing their behaviour is schizophrenic, meaning the investor must hold multiple seemingly contradictory beliefs simultaneously, either by switching between

A. Hubbard, A. Brandenburg

We present the results of simulations of forced turbulence in a slab where the mean kinetic helicity has a maximum near the mid-plane, generating gradients of magnetic helicity of both large and small-scale fields. We also study systems that have poorly conducting buffer zones away from the midplane in order to assess the effects of boundaries. The dynamical

Norrozila Sulaiman, Che Yahaya Yaakub

WiFi is widely implemented in campus wide including administrative, teaching and student's accommodation. Wireless communications are associated with interconnect devices which includes cellular networks, infrared, bluetooth and WiFi enabled devices. It involves mobility and freedom of assessing information anytime and anywhere. A study on WiFi networks

A. Ahmed Jedidi, B. Mohamed Abid

All-Optical Network (AON) is a network where the user-network interface is optical and the data does undergo optical to electrical conversion within the network. AONs are attractive because they promise very high rates, flexible switching and broad application support. There are two technologies for AON: Wavelength Division Multiplexed (WDM) and Optical Time

John J. Matese, Daniel P. Whitmire

We present an updated dynamical and statistical analysis of outer Oort cloud cometary evidence suggesting the sun has a wide-binary Jovian mass companion. The results support a conjecture that there exists a companion of mass ~ 1-4 M_Jup orbiting in the innermost region of the outer Oort cloud. Our most restrictive prediction is that the orientation angles o

Iwan Adhicandra

Due to its large coverage area, low cost of deployment and high speed data rates, WiMAX is a promising technology for providing wireless last-mile connectivity. Physical and MAC layer of this technology refer to the IEEE 802.16e standard, which defines 5 different data delivery service classes that can be used in order to satisfy Quality of Service (QoS) req

Nafiz Imtiaz Bin Hamid, Md. R. H. Khandokar, Taskin Jamal, Md. A. Shoeb

Internet generation is growing accustomed to having broadband access wherever they go and not just at home or in the office, which turns mobile broadband into a reality. This paper aims to look for a suitable mobile broadband solution in the South Asian region through comparative analysis in various perspectives. Both WiMAX and LTE are 4G technologies design

Karmadeva Maharana

In an attempt to facilitate the construction of a quantum theory of gravity, 't Hooft has considered a chiral alternative to the vierbein field in general theory of relativity. These objects, $ f^a{}_{μν}$, behave like the "cube root" of the metric tensor. We try to construct specific representations of these tensors in terms of Dirac $γ$ matrice

Katja Ostermeir, Karen Alim, Erwin Frey

Employing Monte Carlo simulations of semiflexible polymer rings in weak spherical confinement a conformational transition to figure eight shaped, writhed configurations is discovered and quantified.

Jennifer R. Galovich

Consider the elements of the group algebra CS_{n} given by R_{j}=Sigma_{i=1}^{j-1}(ij), for 2<=j<=n. Jucys [3 - 5] and Murphy[7] showed that these elements act diagonally on elements of S_{n} and gave explicit formulas for the diagonal entries. As requested by the late S. Kerov, we give a combinatorial proof of this work in case j=n and present several simil

Mingsheng Long, Liangbin Hu, W. LiMing

The spin density wave and its temperature dependence in oxypnictide are studied in a three-band model. The spin susceptibilities with various interactions are calculated in the random phase approximation(PPA). It is found that the spin susceptibility peaks around the M point show a spin density wave(SDW) with momentum (0, $π$) and a clear stripe-like spin co

C. Barbieri, M. Hjorth-Jensen, C. Giusti, F. D. Pacati

We review some applications of self-consistent Green&#39;s function theory to studies of one- and two-nucleon structure in finite nuclei. Large-scale microscopic calculations that employ realistic nuclear forces are now possible. Effects of long-range correlations are seen to play a dominant role in determining the quenching of absolute spectroscopic factors

A. Passamonti, N. Andersson

We study time evolutions of superfluid neutron stars, focussing on the nature of the oscillation spectrum, the effect of mutual friction force on the oscillations and the hydrodynamical spin-up phase of pulsar glitches. We linearise the dynamical equations of a Newtonian two-fluid model for rapidly rotating backgrounds. In the axisymmetric equilibrium config

Deepak Sridharan, Ranojoy Bose, Glenn S. Solomon, Edo Waks

We compare the photoluminescence spectrum of an indium arsenide (InAs) quantum dot (QD) that is strongly coupled to a photonic crystal cavity under above band excitation (ABE) and quasi-resonant excitation (QRE). We show that off-resonant cavity feeding, which manifests itself in a bare cavity emission peak at the strong coupling point, is suppressed by as m

George B. Mertzios, Derek G. Corneil

Given a graph $G$, the longest path problem asks to compute a simple path of $G$ with the largest number of vertices. This problem is the most natural optimization version of the well known and well studied Hamiltonian path problem, and thus it is NP-hard on general graphs. However, in contrast to the Hamiltonian path problem, there are only few restricted g

Supriya Krishnamurthy, John Ardelius, Erik Aurell, Mads Dam

Tree-based protocols are ubiquitous in distributed systems. They are flexible, they perform generally well, and, in static conditions, their analysis is mostly simple. Under churn, however, node joins and failures can have complex global effects on the tree overlays, making analysis surprisingly subtle. To our knowledge, few prior analytic results for perfor

R. J. Jackson, R. D. Jeffries

We report radial velocities (RVs), projected equatorial velocities (v sin i) and CaII triplet (CaT) chromospheric activity indices for 237 late-K to mid-M candidate members of the young open cluster NGC 2516. These stars have rotation periods between 0.1 and 15 days. Intermediate resolution spectra were obtained using the Giraffe spectrograph at the Very Lar

A. Bernand-Mantel, J. S. Seldenthuis, A. Beukman, H. S. J. van der Zant

We report on the observation of Kondo and split Kondo peaks in single-molecule transistors containing a single spin transition molecule with a Fe2+ ion. Coulomb blockade characteristics reveal a double quantum dot behavior in a parallel configuration, making our system a molecular equivalent to a semiconducting double-quantum-dot system. As the gate voltage

Aihong Tang

STAR&#39;s measurements of directed flow ($v_1$) for pions, kaons (charged and $K_s^0$), protons and antiprotons for Au + Au collisions at $\sqrtsNN = 200$ GeV are presented. Negative $v_1(y)$ slope is observed for pions, antiprotons, protons and kaons. The proton $v_1(y)$ slope at midrapidity is found extremely small. Sizable difference is seen between $v_1

Yuming Wang, Hao Cao, Junhong Chen, Tengfei Zhang

In this paper, we present an automated system, which has the capability to catch and track solar limb prominences based on observations from EUV 304 passband. The characteristic parameters and their evolution, including height, position angle, area, length and brightness, are obtained without manual interventions. By applying the system to the STEREO-B/SECCH

Dion Gijswijt, Guus Regts

A polyhedron P has the Integer Caratheodory Property if the following holds. For any positive integer k and any integer vector w in kP, there exist affinely independent integer vectors x_1,...,x_t in P and positive integers n_1,...,n_t such that n_1+...+n_t=k and w=n_1x_1+...+n_tx_t. In this paper we prove that if P is a (poly)matroid base polytope or if P i

A. Collier Cameron, E. Guenther, B. Smalley, I. McDonald

Most of our knowledge of extrasolar planets rests on precise radial-velocity measurements, either for direct detection or for confirmation of the planetary origin of photometric transit signals. This has limited our exploration of the parameter space of exoplanet hosts to solar- and later-type, sharp-lined stars. Here we extend the realm of stars with known

Xin Wu, Yi Xie

The phase space of a Hamiltonian system is symplectic. However, the post-Newtonian Hamiltonian formulation of spinning compact binaries in existing publications does not have this property, when position, momentum and spin variables $[X, P, S_1, S_2]$ compose its phase space. This may give a convenient application of perturbation theory to the derivation of

Francesco Biscani

In this paper we present two algorithms for the multiplication of sparse Laurent polynomials and Poisson series (the latter being algebraic structures commonly arising in Celestial Mechanics from the application of perturbation theories). Both algorithms first employ the Kronecker substitution technique to reduce multivariate multiplication to univariate mul

F. Fabrizi, H. C. Walker, L. Paolasini, F. de Bergevin

The magnetic structure of multiferroic Ni$_3$V$_2$O$_8$ has been investigated using non-resonant X-ray magnetic scattering. Incident circularly polarized X-rays combined with full polarization analysis of the scattered beam is shown to yield high sensitivity to the components of the cycloidal magnetic order, including their relative phases. New information o

C. Maraston, J. Pforr, A. Renzini, E. Daddi

Fitting synthetic spectral energy distributions (SED) to the multi-band photometry of galaxies to derive their star formation rates (SFR), stellar masses, ages, etc. requires making a priori assumptions about their star formation histories (SFH). A widely adopted parameterization of the SFH, the so-called tau-models where SFR goes as e^{-t/tau) is shown to l

H. C. Spruit

Some established views of the solar magnetic cycle are discussed critically, with focus on two aspects at the core of most models: the role of convective turbulence, and the role of the `tachocline&#39; at the base of the convection zone. The standard view which treats the solar cycle as a manifestation of the interaction between convection and magnetic fiel

B. R. Barrett, B. G. Giraud

The spin density matrix (SDM) used in atomic and molecular physics is revisited for nuclear physics, in the context of the radial density functional theory. The vector part of the SDM defines a &#34;hedgehog&#34; situation, which exists only if nuclear states contain some amount of parity violation.

Marek Ruciński, Dario Izzo, Francesco Biscani

Parallel Global Optimization Algorithms (PGOA) provide an efficient way of dealing with hard optimization problems. One method of parallelization of GOAs that is frequently applied and commonly found in the contemporary literature is the so-called Island Model (IM). In this paper we analyze the impact of the migration topology on the performance of a PGOA wh

Xiao-Wu Chen

This paper consists of three results on Frobenius categories: (1) we give sufficient conditions on when a factor category of a Frobenius category is still a Frobenius category; (2) we show that any Frobenius category is equivalent to an extension-closed exact subcategory of the Frobenius category formed by Cohen-Macaulay modules over some additive category;

Chit Hong Yam, Dario Izzo, Francesco Biscani

We build upon some new ideas in direct transcription methods developed within the Advanced Concepts Team to introduce two improvements to the Sims-Flanagan transcription for low-thrust trajectories. The obtained new algorithm is able to produce an operational trajectory accounting for the real spacecraft dynamics and adapting the segment duration on-line imp

P. Padovani

I highlight the synergies of the Wide Field X-ray Telescope (WFXT) with the next generation radio surveys, including those to be obtained with the Australian Square Kilometre Array Pathfinder and the Square Kilometre Array, and discuss the overlap between the X-ray and radio source populations. WFXT will benefit greatly from the availability of deep radio ca

Pujals Gregory, Cossu Carlo, Depardon Sebastien

Large scale coherent streaks are artificially forced in a well developed turbulent boundary layer at $\Redstar \approx 1000$ using an array of cylindrical roughness elements. Measures of the velocity field with particle image velocimetry reveal the presence of well reproducible, streamwise oriented, steady coherent streaks. We show that the amplitude of thes

Lorenzo Isella, Yannis Drossinos

Nanoparticle agglomeration in a quiescent fluid is simulated by solving the Langevin equations of motion of a set of interacting monomers in the continuum regime. Monomers interact via a radial, rapidly decaying intermonomer potential. The morphology of generated clusters is analyzed through their fractal dimension $d_f$ and the cluster coordination number.

Mike E. Davies, Yonina C. Eldar

In this paper we revisit the sparse multiple measurement vector (MMV) problem where the aim is to recover a set of jointly sparse multichannel vectors from incomplete measurements. This problem has received increasing interest as an extension of the single channel sparse recovery problem which lies at the heart of the emerging field of compressed sensing. Ho

Giovanni Alessandrini

We prove that solutions to elliptic equations in two variables in divergence form, possibly non-selfadjoint and with lower order terms, satisfy the strong unique continuation property.

Mats Brodén, Magnus Wiktorsson

Discrete time hedging in a complete diffusion market is considered. The hedge portfolio is rebalanced when the absolute difference between delta of the hedge portfolio and the derivative contract reaches a threshold level. The rate of convergence of the expected squared hedging error as the threshold level approaches zero is analyzed. The results hinge to a

Gabriela Barenboim, Grigoris Panotopoulos

The viability of a possible cosmological scenario is investigated. The theoretical framework is the constrained next-to-minimal supersymmetric standard model (cNMSSM), with a gravitino playing the role of the lightest supersymmetric particle (LSP) and a neutralino acting as the next-to-lightest supersymmetric particle (NLSP). All the necessary constraints fr

A. M. Shuvaev, S. Engelbrecht, M. Wunderlich, A. Schneider

Magnetoelectric susceptibility of a metamaterial built from split ring resonators have been investigated both experimentally and within an equivalent circuit model. The absolute values have been shown to exceed by two orders of magnitude that of classical magnetoelectric materials. The metamaterial investigated reaches the theoretically predicted value of th

Tim Netzer, Murray Marshall

We look for algebraic certificates of positivity for functions which are not necessarily polynomial functions. Similar questions were examined earlier by Lasserre and Putinar and by Putinar. We explain how these results can be understood as results on hidden positivity: The required positivity of the functions implies their positivity when considered as poly

Marco Baldi, Marco Bianchi, Franco Chiaraluce

This paper is a first study on the topic of achieving physical layer security by exploiting non-systematic channel codes. The chance of implementing transmission security at the physical layer is known since many years in information theory, but it is now gaining an increasing interest due to its many possible applications. It has been shown that channel cod

Alexander S. Pirozhkov, Masaki Kando, Timur Zh. Esirkepov, Eugene N. Ragozin

X-ray devices are far superior to optical ones for providing nanometre spatial and attosecond temporal resolutions. Such resolution is indispensable in biology, medicine, physics, material sciences, and their applications. A bright ultrafast coherent X-ray source is highly desirable, for example, for the diffractive imaging of individual large molecules, vir

D. Alfe`, M. J. Gillan

We show how the path-integral formulation of quantum statistical mechanics can be used to construct practical {\em ab initio} techniques for computing the chemical potential of molecules adsorbed on surfaces, with full inclusion of quantum nuclear effects. The techniques we describe are based on the computation of the potential of mean force on a chosen mole

Hermund André Torkildsen

We use a geometric description of $m$-cluster categories of Dynkin type $A$ to count the the number of coloured quivers in the $m$-mutation class of quivers of Dynkin type $A$. This is related to angulations of polygons and the cell-growth problem.

M. Avlund, C. Ellegaard, M. Oxborrow, T. Guhr

We measure elastomechanical spectra for a family of thin shells. We show that these spectra can be described by a &#34;semiclassical&#34; trace formula comprising periodic orbits on geodesics, with the periods of these orbits consistent with those extracted from experiment. The influence of periodic orbits on spectra in the case of two-dimensional curved geo

N. Ramakrishnan, P. B. Sunil Kumar, John H. Ipsen

We present a method for simulating fluid vesicles with in-plane orientational ordering. The method involves computation of local curvature tensor and parallel transport of the orientational field on a randomly triangulated surface. It is shown that the model reproduces the known equilibrium conformation of fluid membranes and work well for a large range of b

C. Quesne

The family of Tremblay-Turbiner-Winternitz Hamiltonians $H_k$ on a plane, corresponding to any positive real value of $k$, is shown to admit a ${\cal N} = 2$ supersymmetric extension of the same kind as that introduced by Freedman and Mende for the Calogero problem and based on an ${\rm osp}(2/2, \R) \sim {\rm su}(1,1/1)$ superalgebra. The irreducible repres

Xi Chen, Qing-Rong Zheng, Gang Su

The spin transfer effect in ferromagnet-quantum dot (insulator)-ferromagnet Aharonov-Bohm (AB) ring system with Rashba spin-orbit (SO) interactions is investigated by means of Keldysh nonequilibrium Green function method. It is found that both the magnitude and direction of the spin transfer torque (STT) acting on the right ferromagnet electrode can be effec

A. -M. Broomhall, W. J. Chaplin, Y. Elsworth, T. Appourchaux

We describe and use two different statistical approaches to try and detect low-frequency solar oscillations in Sun-as-a-star data: a frequentist approach and a Bayesian approach. We have used frequentist statistics to search contemporaneous Sun-as-a-star data for coincident, statistically-prominent features. However, we find that this approach leads to numer

Yu. I. Belchenko, E. A. Gilev, Z. K. Silagadze

The textbook contains the problems in mechanics and special relativity for physics departments of universities. Many original problems were proposed by active scientists from the institutes of the Siberian Branch of Russian Academy of Science, while teaching at the Novosibirsk State University. The problems have been used in seminars, students&#39; homework

Mathis Plapp

Three different topics in phase-field modelling of solidification are discussed, with particular emphasis on the limitations of the currently available modelling approaches. First, thin-interface limits of two-sided phase-field models are examined, and it is shown that the antitrapping current is in general not sufficient to remove all thin-interface effects

Enzo Orlandini, Attilio L. Stella, Carlo Vanderzande

We study knotted polymers in equilibrium with an array of obstacles which models confinement in a gel or immersion in a melt. We find a crossover in both the geometrical and the topological behavior of the polymer. When the polymers&#39; radius of gyration, $R_G$, and that of the region containing the knot, $R_{G,k}$, are small compared to the distance b bet

M. Leijnse, M. R. Wegewijs, K. Flensberg

We present a detailed study of the non-linear thermoelectric properties of a molecular junction, represented by a dissipative Anderson-Holstein model. A single orbital level with strong Coulomb interaction is coupled to a localized vibrational mode and we account for both electron and phonon exchange with both electrodes, investigating how these contribute t

Soumen Mandal

The angle dependent magnetoresistance study on [001] and [110] La$_{2 / 3}$Sr$_{1 / 3}$MnO$_{3}$ thin films show that the anisotropy energy of [110] films is higher when compared with a [001] oriented La$_{2 / 3}$Sr$_{1 / 3}$MnO$_{3}$ film of similar thickness. The data has been analyzed in the light of multidomain model and it is seen that this model correc

Karine Demyk, S. Bottinelli, Emmanuel Caux, Charlotte Vastel

High deuterium fractionation is observed in various types of environment such as prestellar cores, hot cores and hot corinos. It has proven to be an efficient probe to study the physical and chemical conditions of these environments. The study of the deuteration of different molecules helps us to understand their formation. This is especially interesting for

Laurent Labonté, Dominique Pagnoux, Philippe Roy, Bahloul Faouzi

Careful numerical computations show that very slight geometrical imperfections of the cross-section of actual large air-fraction holey fibres (d/Λ > 0.6) may induce surprisingly high birefringence, corresponding to beat lengths as short as few millimeters. The spectral variations of this birefringence obeys laws similar to those of elliptical core Hi-Bi hole

Guillermo F. Hagele, Yago Ascasibar, Anita M. S. Richards, Monica V. Cardaci

We report sub-arcsecond scale radio continuum observations of a field of 35 by 22 arcmin centred in NGC3351 obtained with the Multi-Element Radio Linked Interferometer Network (MERLIN). We found 23 radio sources in this field, 6 of which are projected within the D$_{25}$ isophote of the galaxy, and 3 are located inside the central 100 arcsec in radius. Two o

Dean Rickles

The dominance of string theory in the research landscape of quantum gravity physics (despite any direct experimental evidence) can, I think, be justified in a variety of ways. Here I focus on an argument from mathematical fertility, broadly similar to Hilary Putnam&#39;s &#39;no miracles argument&#39; that, I argue, many string theorists in fact espouse. Str

Ronit Bustin, Miquel Payaró, Daniel P. Palomar, Shlomo Shamai

This paper extends the &#34;single crossing point&#34; property of the scalar MMSE function, derived by Guo, Shamai and Verdú (first presented in ISIT 2008), to the parallel degraded MIMO scenario. It is shown that the matrix Q(t), which is the difference between the MMSE assuming a Gaussian input and the MMSE assuming an arbitrary input, has, at most, a sin

Djoerd Hiemstra, Claudia Hauff

We propose to use MapReduce to quickly test new retrieval approaches on a cluster of machines by sequentially scanning all documents. We present a small case study in which we use a cluster of 15 low cost ma- chines to search a web crawl of 0.5 billion pages showing that sequential scanning is a viable approach to running large-scale information retrieval ex

Felix Effenberger, Daniel Weiskopf

We present a novel approach to finding critical points in cell-wise barycentrically or bilinearly interpolated vector fields on surfaces. The Poincar\e index of the critical points is determined by investigating the qualitative behavior of 0-level sets of the interpolants of the vector field components in parameter space using precomputed combinatorial resul

Viresh Patel

In this paper, we show that for an $n$-vertex graph $G$ of genus $g$, the edge expansion of $G$ can be determined in time $n^{O(g^2)}$. We show that the same is true for various other similar measures of edge connectivity.

A. Yu. Isupov

The ngdp framework advanced topics are described. Namely we consider work with CAMAC hardware, &#34;selfflow&#34; nodes for the data acquisition systems with the As-Soon-As-Possible policy, ng_mm(4) as alternative to ng_socket(4), the control subsystem, user context utilities, events representation for the ROOT package, test and debug nodes, possible advance

Ravinder Yadav, Rinkle Rani Aggarwal

The main issue in the optical transmission is switching speed. The optical packet switching faces many significant challenges in processing and buffering. The generalized multilevel protocol switching seeks to eliminate the asynchronous transfer mode and synchronous optical network layer, hence the implementation of IP over WDM (wave length division multiple

S. Ramakrishnan, S. Venugopalan, A. Ebenezer Jeyakumar

In resent years ANN is widely reported for modeling in different areas of science including electro chemistry. This includes modeling of different technological batteries such as lead acid battery, Nickel cadmium batteries etc. Lithium ion batteries are advance battery technology which satisfy most of the space mission requirements. Low earth orbit (LEO)spac

Anuj Mehra, Anupam Shukla, Mahender Kumawat, Rajiv Ranjan

Biometric authentication techniques are more consistent and efficient than conventional authentication techniques and can be used in monitoring, transaction authentication, information retrieval, access control, forensics, etc. In this paper, we have presented a detailed comparative analysis between Principle Component Analysis (PCA) and Independent Componen

P. Kamakshi, A. Vinaya Babu

The main objective of data mining is to extract previously unknown patterns from large collection of data. With the rapid growth in hardware, software and networking technology there is outstanding growth in the amount data collection. Organizations collect huge volumes of data from heterogeneous databases which also contain sensitive and private information

A. Yu. Isupov

The ngdp framework is intended to provide a base for the data acquisition (DAQ) system software. The ngdp&#39;s design key features are: high modularity and scalability; usage of the kernel context (particularly kernel threads) of the operating systems (OS), which allows to avoid preemptive scheduling and unnecessary memory--to--memory copying between contex

A. Piñeiro, A. S. Botana, V. Pardo, D. Baldomir

Electronic structure calculations were performed on the compound CoS$_2$, an itinerant ferromagnet whose magnetic properties can be understood in terms of spin fluctuation theory. We have identified nesting features in the Fermi surface of the compound, active for long wavelength spin fluctuations. The electronic structure of the material is close to a half-

N. Tsoneva, H. Lenske

Systematic studies of dipole and other multipole excitations in stable and exotic nuclei are discussed theoretically. Exploring the relation of the strengths of low-energy dipole and quadrupole pygmy resonances to the thickness of the neutron (proton) skin a close connection between static and dynamic properties of the nucleus is observed. The fine structure

Khawar Hameed, Kamran Ahsan, Weijun Yang

Mobile commerce is enabling the development of additional revenue streams for organizations through the delivery of chargeable mobile services. According to the European Information Technology Observatory, the total amount of revenue generated by mobile commerce was reported to be less than £9 million in the United Kingdom in 2001. By 2005 this had, at least