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December 2010 arXiv papers — page 38

Showing 3,7013,800 of 6,281 papers

  1. K. Poppenhaeger

    We investigated the coronal activity of planet-hosting stars by means of statistical analysis for a complete sample of stars in the solar neighborhood. We find no observational evidence that Star-Planet Interactions are at work in this sample, at least not at the sensitivity levels of our observations. We additionally test the upsilon Andromedae system, an F

  2. Masumi Kasai

    We present an analytical approximation formula for the growth function in a spatially flat cosmology with dust and a cosmological constant. Our approximate formula is written simply in terms of a rational function. We also show the approximate formula in a dust cosmology without a cosmological constant, directly as a function of the scale factor in terms of

  3. Guillaume Inria Moroz, Fabrice Rouiller, Damien Chablat, Philippe Wenger

    This paper investigates the cuspidal configurations of 3-RPR parallel manipulators that may appear on their singular surfaces in the joint space. Cusp points play an important role in the kinematic behavior of parallel manipulators since they make possible a non-singular change of assembly mode. In previous works, the cusp points were calculated in sections

  4. Damien Chablat

    The aim of this paper is to compute of the generalized aspects, i.e. the maximal singularity-free domains in the Cartesian product of the joint space and workspace, for a planar parallel mechanism in using quadtree model and interval analysis based method. The parallel mechanisms can admit several solutions to the inverses and the direct kinematic models. Th

  5. M. Giroletti, F. Panessa

    Following the high detection rate achieved by EVN observations of the central regions of local Seyfert galaxies (Giroletti & Panessa 2009, ApJL 706, 260), we have targeted a few additional sources from a complete sample. We have detected three more sources (NGC 3982, NGC 3227, and NGC 4138) at both 1.6 and 5 GHz and present preliminary results. Moreover, the

  6. Marcello Giroletti, Z. Paragi, H. Bignall, A. Doi

    The detection of gamma-ray emission by Fermi-LAT from the radio loud Narrow Line Seyfert 1 PMN J0948+0022 (Abdo et al. 2009, ApJ 699, 976) triggered a multi-wavelength campaign between March and July 2009. Given its high compactness (Doi et al. 2006, PASJ 58, 829), inverted spectrum, and 0deg declination, the source was an ideal target to observe at 22 GHz w

  7. Guillaume Inria Moroz, Damien Chablat, Philippe Wenger, Fabrice Rouiller

    This paper investigates the existence conditions of cusp points in the design parameter space of the R\underline{P}R-2P\underline{R}R parallel manipulators. Cusp points make possible non-singular assembly-mode changing motion, which can possibly increase the size of the aspect, i.e. the maximum singularity free workspace. The method used is based on the noti

  8. Maxime Amblard, Alain Lecomte, Christian Retoré

    We first recall some basic notions on minimalist grammars and on categorial grammars. Next we shortly introduce partially commutative linear logic, and our representation of minimalist grammars within this categorial system, the so-called categorial minimalist grammars. Thereafter we briefly present λμ-DRT (Discourse Representation Theory) an extension of λ-

  9. Leonid S. Revin, Andrey L. Pankratov

    We analyze a two-level quantum system, describing the phase qubit, during a single-pulse readout process by a numerical solution of the time-dependent Schroedinger equation. It has been demonstrated that the readout error has a minimum for certain values of the system`s basic parameters. In particular, the optimization of the qubit capacitance and the readou

  10. A. L. Pankratov, S. N. Vdovichev, I. M. Nefedov, I. R. Karetnikova

    The effect of noise on the process of high-speed remagnetization of vortex state of a pentagonal array of five circular magnetic nanoparticles is studied by means of computer simulation of Landau-Lifshits model. The mean switching time and its standard deviation of the reversal between the counterclockwise and clockwise vorticities have been computed. It has

  11. Laurent Bruneau, Stephan De Bievre, Claude-Alain Pillet

    In the single band tight-binding approximation, we consider the transport properties of an electron in a homogeneous static electric field. We show that repeated interactions of the electron with two-level systems in thermal equilibrium suppress the Bloch oscillations and induce a steady current, the statistical properties of which we study.

  12. Laleh Memarzadeh, Stefano Mancini

    We investigate the possibility of chaining qubits by letting pairs of nearest neighbours qubits dissipating into common environments. We then study entanglement dynamics within the chain and show that steady state entanglement can be achieved.

  13. Christian Gérard, Fumio Hiroshima, Annalisa Panati, A. Suzuki

    We consider the Nelson model on some static space-times and investigate the problem of absence of a ground state. Nelson models with variable coefficients arise when one replaces in the usual Nelson model the flat Minkowski metric by a static metric, allowing also the boson mass to depend on position. We investigate the absence of a ground state of the Hamil

  14. Shunichi Tatematsu, Erika Satomi, Yoshiaki Kobayashi, Masatoshi Sato

    Results of transport, magnetic, thermal, and 75As-NMR measurements are presented for superconducting Sr2VFeAsO3 with an alternating stack of FeAs and perovskite-like block layers. Although apparent anomalies in magnetic and thermal properties have been observed at ~150 K, no anomaly in transport behaviors has been observed at around the same temperature. The

  15. B. F. L. Ward, S. A. Yost

    The new IR-improved Dokshitzer-Gribov-Lipatov-Altarelli-Parisi-Callan-Symanzik (DGLAP-CS) kernels recently developed by one of us is implemented in the HERWIG6.5 environment to generate a new MC, HERWIRI1.0(31), for hadron-hadron scattering at high energies. The comparison between the parton shower generated by the standard DGLAP-CS kernels and that generate

  16. Francis Bernardeau, Cyril Pitrou, Jean-Philippe Uzan

    This article constructs flat-sky approximations in a controlled way in the context of the cosmic microwave background observations for the computation of both spectra and bispectra. For angular spectra, it is explicitly shown that there exists a whole family of flat-sky approximations of similar accuracy for which the expression and amplitude of next to lead

  17. J. Libby

    Measurements of D0 meson strong-phase parameters in quantum-correlated psi(3770) -> D0 D0bar decays by the CLEO collaboration are presented. These measurements play an important role in the determination of the unitarity triangle angle gamma/phi3 from B-meson decays. Measurements of the strong-phase parameters for D0->K0 pi+ pi-, D0 -> K0 K+ K-, D0 -> K- pi+

  18. E. Rigliaco, A. Natta, S. Randich, L. Testi

    We present the first observations of a probable brown dwarf, obtained with the new spectrograph X-shooter mounted on the UT2@VLT. The target (2MASS J053825.4-024241) is a 0.06 Msun object in the star-formation region sigma Orionis. The X-shooter spectrum covers simultaneously the whole range from UV to NIR (300-2500 nm). The J053825.4-024241 spectrum is rich

  19. S. Abiteboul, G. Gottlob, M. Manna

    A distributed XML document is an XML document that spans several machines. We assume that a distribution design of the document tree is given, consisting of an XML kernel-document T[f1,...,fn] where some leaves are "docking points" for external resources providing XML subtrees (f1,...,fn, standing, e.g., for Web services or peers at remote locations)

  20. Chia-Min Lin

    In this talk, I will explain how to reduce the spectral index to be n_s=0.96 for supernatural inflation. I will also show the constraint to the reheating temperature from Big Bang Nucleosynthesis of both thermal and non-thermal gravitino production.

  21. Seokcheon Lee

    In spite of their original discrepancy, both dark energy and modified theory of gravity can be parameterized by the effective equation of state (EOS) $ω$ for the expansion history of the Universe. A useful model independent approach to the EOS of them can be given by so-called Chevallier-Polarski-Linder (CPL) parametrization where two parameters of it ($ω_{0

  22. Takashi Kaneko

    Disconnected diagrams give crucial contributions to the physics of flavor singlet hadrons and to scalar form factors of non-singlet hadrons. Naive lattice calculation of the disconnected diagrams, however, requires a huge number of fermion matrix inversions and hence a prohibitively large computational cost. In this article, we present recent studies of the

  23. Stephane Vennes, Adela Kawka, Peter Nemeth

    We present an analysis of high-dispersion and high signal-to-noise ratio spectra of the DAZ white dwarf GALEX J1931+0117. The spectra obtained with the VLT-Kueyen/UV-Visual Echelle Spectrograph show several well-resolved Si II spectral lines enabling a study of pressure effects on line profiles. We observed large Stark shifts in silicon lines in agreement wi

  24. Simon J. Murphy, Warrick A. Lawson, Michael S. Bessell

    We have identified several lithium-rich low-mass (0.08<M<0.3 Msun). stars within 5.5 deg of the young open cluster Eta Chamaeleontis, nearly four times the radius of previous search efforts. We propose 4 new probable cluster members and 3 possible members requiring further investigation. Candidates were selected on the basis of DENIS and 2MASS photometry, NO

  25. Philippos K. Tsourkas, Wanli Liu, Somkanya C Das, Susan K. Pierce

    B cells receptor (BCR) signaling in response to membrane-bound antigen increases with antigen affinity, a process known as affinity discrimination. We use computational modeling to show that B cell affinity discrimination requires that kinetic proofreading predominate over serial engagement. We find that if BCR molecules become signaling-capable immediately

  26. Adela Kawka, Stephane Vennes, Frantisek Dinnbier, Helena Cibulkova

    We present an abundance analysis of a sample of 33 hydrogen-rich (DA) white dwarfs. We have used archival high-resolution spectra to measure abundances of calcium, magnesium and iron in a set of 30 objects. In addition, we present preliminary calcium abundances in three new white dwarfs based on low-dispersion spectra. We investigate some abundance ratios (M

  27. C. P. Burgess, L. van Nierop

    Extra-dimensional models can involve bulk pseudo-Goldstone bosons (pGBs) whose shift symmetry is explicitly broken only by physics localized on branes. Reliable calculation of their low-energy potential is often difficult because it requires details of the stabilization of the extra dimensions. In rugby ball solutions, for which two compact extra dimensions

  28. Youhei Yamaji, Masatoshi Imada

    We study roles of electron correlations on topological insulators on the honeycomb lattice with the spin-orbit interaction. Accurate variational Monte Carlo calculations show that the increasing on-site Coulomb interactions cause a strong suppression of the charge Drude weight in the helical-edge metallic states leading to a presumable Mott transition from a

  29. Kefeng Liu, Pan Peng

    Based on the proof of Labastida-Mari{ñ}o-Ooguri-Vafa conjecture \cite{lmov}, we derive an infinite product formula for Chern-Simons partition functions, the generating function of quantum $\fsl_N$ invariants. Some symmetry properties of the infinite product will also be discussed.

  30. Kefeng Liu, Pan Peng

    We outline a proof of a remarkable conjecture of Labastida-Mari{ñ}o-Ooguri-Vafa about certain new algebraic structures of quantum link invariants and the integrality of infinite family of new topological invariants. Our method is based on the cut-and-join analysis and a special rational ring characterizing the structure of the Chern-Simons partition function

  31. Chengze Liu, Eric W. Peng, Andres Jordan, Laura Ferrarese

    We use the largest homogeneous sample of globular clusters (GCs), drawn from the ACSVCS and ACSFCS, to investigate the color gradients of GC systems in 76 early-type galaxies. We find that most GC systems possess an obvious negative gradient in g-z color (bluer outwards). For GC systems displaying color bimodality, both metal-rich and metal-poor GC subpopula

  32. Vishal Gupta, Ashutosh Saxena

    Data Management portfolio within an organization has seen an upsurge in initiatives for compliance, security, repurposing and storage within and outside the organization. When such initiatives are being put to practice care must be taken while granting access to data repositories for analysis and mining activities. Also, initiatives such as Master Data Manag

  33. Jongyook Park, Jack H. Koolen, Greg Markowsky

    In this paper, we show that for given positive integer C, there are only finitely many distance-regular graphs with valency k at least three, diameter D at least six and k2/k<=C. This extends a conjecture of Bannai and Ito.

  34. Badri N. Vellambi, Nima Torabkhani, Faramarz Fekri

    This work investigates the effect of finite buffer sizes on the throughput capacity and packet delay of line networks with packet erasure links that have perfect feedback. These performance measures are shown to be linked to the stationary distribution of an underlying irreducible Markov chain that models the system exactly. Using simple strategies, bounds o

  35. R. Manohar, A. Mukherjee, D. Chakrabarti

    We investigate the generalized parton distributions (GPDs) for u and d quarks in a proton in transverse and longitudinal position space using a recent phenomenological parametrization. We take nonzero skewness ζand consider the region x> ζ. Impact parameter space representation of the GPD E is found to depend sharply on the parameters used within the model,

  36. E. D. Kuhnle, S. Hoinka, P. Dyke, H. Hu

    The contact ${\cal I}$, introduced by Tan, has emerged as a key parameter characterizing universal properties of strongly interacting Fermi gases. For ultracold Fermi gases near a Feshbach resonance, the contact depends upon two quantities: the interaction parameter $1/(k_F a)$, where $k_F$ is the Fermi wave-vector and $a$ is the $s$-wave scattering length,

  37. Chung-Lin Shan

    We reexamine the model-independent data analysis methods for extracting properties of Weakly Interacting Massive Particles (WIMPs) by using data (measured recoil energies) from direct Dark Matter detection experiments directly and, as a more realistic study, consider a small fraction of residue background events, which pass all discrimination criteria and th

  38. Alice Guionnet, Ofer Zeitouni

    We study the eigenvalues of non-normal square matrices of the form A_n=U_nT_nV_n with U_n,V_n independent Haar distributed on the unitary group and T_n real diagonal. We show that when the empirical measure of the eigenvalues of T_n converges, and T_n satisfies some technical conditions, all these eigenvalues lie in a single ring.

  39. Xiang Xiong, Xiao-Chun Chen, Mu Wang, Ru-Wen Peng

    We report here the designing of optically-nonactive metamaterial by assembling metallic helices with different chirality. With linearly polarized incident light, pure electric or magnetic resonance can be selectively realized, which leads to negative permittivity or negative permeability accordingly. Further, we show that pure electric or magnetic resonance

  40. Nima Torabkhani, Badri N. Vellambi, Faramarz Fekri

    Exact queueing analysis of erasure networks with network coding in a finite buffer regime is an extremely hard problem due to the large number of states in the network. In such networks, packets are lost due to either link erasures or due to blocking due to full buffers. In this paper, a block-by-block random linear network coding scheme with feedback on the

  41. Nima Torabkhani, Badri N. Vellambi, Faramarz Fekri

    The exact Markov modeling analysis of erasure networks with finite buffers is an extremely hard problem due to the large number of states in the system. In such networks, packets are lost due to either link erasures or blocking by the full buffers. In this paper, we propose a novel method that iteratively estimates the performance parameters of the network a

  42. V. M. Ishchuk, V. L. Sobolev

    Results of detailed investigations of stability of phases in substances with the small difference in the energies of the ferroelectric and the antiferroelectric types of dipole ordering are presented. It is shown that interaction of locally separated domains of the ferroelectric and antiferroelectric phases stabilizes a nonuniform state of the samples. The a

  43. Lijuan Ruan

    The di-electron analysis for 200 GeV p+p collisions is presented in this article. The cocktail simulations of di-eletrons from light flavor meson decays and heavy flavor decays are reported and compared with data. The perspectives for di-lepton measurements in Au+Au collisions are discussed.

  44. Stefano Bellucci, Bhupendra Nath Tiwari

    We present the scalar moduli stabilization from the perspective of the real intrinsic geometry. In this paper, we describe the physical nature of the vacuum moduli fluctuations of an arbitrary Fayet configuration. For finitely many abelian scalar fields, we show that the framework of the real intrinsic geometry investigates the mixing between the marginal an

  45. Shyam Chikatamarla, Ilya Karlin

    It is shown both analytically and numerically that the suggested lattice Boltzmann model on rectangular grids leads to anisotropic dissipation of fluid momentum and thus it does not recover Navier-Stokes equations. Hence, it cannot be used for the simulation of hydrodynamics.

  46. Gao-Chan Yong

    Based on the isospin-dependent Boltzmann-Uehling-Uhlenbeck transport model and the scaling model according to nucleon effective mass, effects of elastic and inelastic NN scattering cross sections on pion-/pion+ in the neutron-rich reaction of Ca48+Ca48 at a beam energy of 400 MeV/nucleon are studied. It is found that cross-section effects of both NN elastic

  47. Gregory E. Fasshauer, Fred J. Hickernell, Henryk Woźniakowski

    This article studies the problem of approximating functions belonging to a Hilbert space $H_d$ with an isotropic or anisotropic Gaussian reproducing kernel, $$ K_d(\bx,\bt) = \exp\left(-\sum_{\ell=1}^dγ_\ell^2(x_\ell-t_\ell)^2\right) \ \ \ \mbox{for all}\ \ \bx,\bt\in\reals^d. $$ The isotropic case corresponds to using the same shape parameters for all coord

  48. M. Unger

    NA61/SHINE is a fixed-target experiment to study hadron production in hadron-nucleus and nucleus-nucleus collisions at the CERN SPS. Due to the very good acceptance and particle identification in forward direction, NA61/SHINE is well suited for measuring particle production to improve the reliability of air shower simulations. Data with proton and pion beams

  49. Pierre de Buyl, David Mukamel, Stefano Ruffo

    Long-lived quasistationary states, associated with stationary stable solutions of the Vlasov equation, are found in systems with long-range interactions. Studies of the relaxation time in a model of $N$ globally coupled particles moving on a ring, the Hamiltonian Mean Field model (HMF), have shown that it diverges as $N^γ$ for large $N$, with $γ\simeq 1.7$ f

  50. Christine Nattrass

    Previous studies have indicated that the near-side peak of high-pT triggered di-hadron correlations can be decomposed into two parts, a jet-like correlation and the ridge. We present data from Cu+Cu and Au+Au collisions at sqrt(sNN)=62 and 200 GeV, which should allow more robust tests of models. The jet-like correlation is narrow in both azimuth and pseudora

  51. Nikita Alexeev, Friedrich Götze, Alexander Tikhomirov

    We consider products of independent large random rectangular matrices with independent entries. The limit distribution of the expected empirical distribution of singular values of such products is computed. The distribution function is described by its Stieltjes transform, which satisfies some algebraic equation. In the particular case of square matrices we

  52. Stewart Wilcox

    We first consider the rational Cherednik algebra corresponding to the action of a finite group on a complex variety, as defined by Etingof. We define a category of representations of this algebra which is analogous to &#34;category O&#34; for the rational Cherednik algebra of a vector space. We generalise to this setting Bezrukavnikov and Etingof&#39;s resul

  53. Keivan G. Stassun, Leslie Hebb, Kevin Covey, Andrew A. West

    The difference in stellar structure above and below spectral type ~M4 is expected to be a very important one, connected directly or indirectly to a variety of observational phenomena in cool stars---such as rotation, activity, magnetic field generation and topology, timescales for evolution of these, and even the basic mass-radius relationship. In this Cool

  54. L. R. Churchill, M. V. DePalatis, M. S. Chapman

    We have measured the reaction rates of trapped, buffer gas cooled Th$^{3+}$ and various gases and have analyzed the reaction products using trapped ion mass spectrometry techniques. Ion trap lifetimes are usually limited by reactions with background molecules, and the high electron affinity of multiply charged ions such as Th$^{3+}$ make them more prone to l

  55. Jesse Leo Kass

    A basic technique for studying a family of Jacobian varieties is to extend the family by adding degenerate fibers. Constructing an extension requires a choice of fibers, and one typically chooses to include either degenerate group varieties or degenerate moduli spaces of sheaves. Here we relate these two different approaches when the base of the family is a

  56. Duane A. Dicus, Shao-Feng Ge, Wayne W. Repko

    We explore the consequences of the neutrino mass matrix having a hidden $\mathcal{Z}_2$ symmetry and one zero eigenvalue. When implemented, these two conditions give relations among the mixing angles. In addition, fitting these relations to the existing oscillation data allows limits to be placed on the parameter of the symmetry.

  57. D. S. Kaparulin, S. L. Lyakhovich, A. A. Sharapov

    Any local field theory can be equivalently reformulated in the so-called unfolded form. General unfolded equations are non-Lagrangian even though the original theory is Lagrangian. Using the theory of a scalar field as a basic example, the concept of Lagrange anchor is applied to perform a consistent path-integral quantization of unfolded dynamics. It is sho

  58. P. Maniadis, B. S. Alexandrov, A. R. Bishop, K. Ø. Rasmussen

    We demonstrate that period-doubled discrete breathers appear from the anti-continuum limit of the driven Peyrard-Bishop-Dauxois model of DNA. These novel breathers result from a stability overlap between sub-harmonic solutions of the driven Morse oscillator. Sub-harmonic breathers exist whenever a stability overlap is present within the Feigenbaum cascade to

  59. V. Cherepanov, S. Eidelman

    We use experimental data on $e^{+}e^{-} \rightarrow ηπ^{+}π^{-}$ and $τ^{-} \to ηπ^{-}π^{0}ν_τ$ to test conservation of vector current (CVC) by comparing the predicted hadronic spectrum and branching fraction with the $τ$ decay data. Based on the corresponding $e^+e^-$ data and CVC, we also calculate the branching fraction of $τ^{-} \to η^\primeπ^{-}π^{0}ν_τ

  60. Bin Liu, Yun-Chuan Dai, Xian-Ru Hu, Jian-Bo Deng

    The non-local Machian model is regarded as an alternative theory of gravitation which states that all particles in the Universe as a &#39;gravitationally entangled&#39; statistical ensemble. It is shown that the Klein-Gordon equation can be derived within this Machian model of the universe. The crucial point of the derivation is the activity of the Machian e

  61. F. Colomo, V. Noferini, A. G. Pronko

    The arctic curve, i.e. the spatial curve separating ordered (or `frozen&#39;) and disordered (or `temperate) regions, of the six-vertex model with domain wall boundary conditions is discussed for the root-of-unity vertex weights. In these cases the curve is described by algebraic equations which can be worked out explicitly from the parametric solution for t

  62. A. Imaanpur, M. Naghdi

    We introduce two ansatzs for the 3-form potential of Euclidean 11d supergravity on skew-whiffed AdS_4 X S^7 background which results in two scalar modes with m^2=-2 on AdS_4. Being conformally coupled with a quartic interaction it is possible to find the exact solutions of the scalar equation on this background. These modes turn out to be invariant under SU(

  63. Jean Bernard Lasserre

    We provide convergent hierarchies for the cone C of copositive matrices and its dual, the cone of completely positive matrices. In both cases the corresponding hierarchy consists of nested spectrahedra and provide outer (resp. inner) approximations for C (resp. for its dual), thus complementing previous inner (resp. outer) approximations for C (for the dual)

  64. Louigi Addario-Berry, Kevin Ford

    We determine, to within O(1), the expected minimal position at level n in certain branching random walks. The walks under consideration have displacement vector (v_1,v_2,...), where each v_j is the sum of j independent Exponential(1) random variables and the different v_i need not be independent. In particular, our analysis applies to the Poisson-Dirichlet b

  65. Sahinur Reja, Sudhakar Yarlagadda, Peter B. Littlewood

    We derive an effective Hamiltonian for the one-dimensional Hubbard-Holstein model, valid in a regime of both strong electron-electron (e-e) and electron-phonon (e-ph) interactions and in the non-adiabatic limit ($t/ω_0 \leq 1$), by using a non-perturbative approach. We obtain the phase diagram at quarter-filling by employing a modified Lanczos method and stu

  66. Fatima Cheniour, Najib Mahdou

    This paper deals with well-known notion of $PF$-rings, that is, rings in which principal ideals are flat. We give a new characterization of $PF$-rings. Also, we provide a necessary and sufficient condition for $R\bowtie I$ (resp., $R/I$ when $R$ is a Dedekind domain or $I$ is a primary ideal) to be $PF$-ring. The article includes a brief discussion of the sc

  67. M. R. Khellat

    We make an extensive use of BLM approach to study details of predicting higher order corrections based on the approach. This way we are able to test two procedures to improve the prediction process. Beside the main line of the two procedures it is found out that overall normalization could change BLM patterns effectively. Finally we try to find out whether a

  68. Jaydip Sen

    The purpose of a wireless sensor network (WSN) is to provide the users with access to the information of interest from data gathered by spatially distributed sensors. Generally the users require only certain aggregate functions of this distributed data. Computation of this aggregate data under the end-to-end information flow paradigm by communicating all the

  69. Nicolaos Matsakis

    In this survey we investigate the application of the Adleman-Lipton model on Rural Postman problem, which given an undirected graph $G=(V,E)$ with positive integer lengths on each of its edges and a subset $E^{&#39;}\subseteq E$, asks whether there exists a hamiltonian circuit that includes each edge of $E^{&#39;}$ and has total cost (sum of edge lengths) le

  70. Jaydip Sen, Munir Sayyad, Basavaraj Hooli

    The communications sector is undergoing significant changes, with the emergence of a number of platforms available to provide a different range of services. Some of these platforms are complementary to each other, while others are competitive, or can provide a valid substitute for some of the services provided. Up till now, the most important communications

  71. Andreas Holmstrom, Jakob Scholbach

    This paper introduces a new cohomology theory for schemes of finite type over an arithmetic ring. The main motivation for this Arakelov-theoretic version of motivic cohomology is the conjecture on special values of $L$-functions and zeta functions formulated by the second author. Taking advantage of the six functors formalism in motivic stable homotopy theor

  72. Taras Banakh, Volodymyr Mykhaylyuk, Lyubomyr Zdomskyy

    For a non-isolated point $x$ of a topological space $X$ the network character $nw_χ(x)$ is the smallest cardinality of a family of infinite subsets of $X$ such that each neighborhood $O(x)$ of $x$ contains a set from the family. We prove that (1) each infinite compact Hausdorff space $X$ contains a non-isolated point $x$ with $nw_χ(x)=\aleph_0$; (2) for each

  73. Jaydip Sen

    Wireless mesh networks (WMNs) are evolving as a key technology for next-generation wireless networks showing raid progress and numerous applications. These networks have the potential to provide robust and high-throughput data delivery to wireless users. In a WMN, high speed routers equipped with advanced antennas, communicate with each other in a multi-hop

  74. Jaydip Sen

    In a multi-hop mobile ad hoc network (MANET), mobile nodes cooperate to form a network without using any infrastructure such as access points or base stations. The mobility of the nodes and the fundamentally limited capacity of the wireless medium, together with wireless transmission effects such as attenuation, multi-path propagation, and interference combi

  75. Jaydip Sen

    Wireless sensor networks (WSNs) have recently attracted a lot of interest in the research community due their wide range of applications. Unfortunately, these networks are vulnerable to numerous security threats that can adversely affect their proper functioning. This problem is more critical if the network is deployed for some mission-critical applications

  76. Xian-Hui Ge, Kwanghyun Jo, Sang-Jin Sin

    We consider the AdS$_4$ RN black hole and work out the momentum dependent hydrodynamic analysis for the vector modes. We also perform the spectral function calculation of the dual field theory. As an application, we consider the permittivity and permeability and find that for low frequency regime, the index of refraction is found to be negative, supporting t

  77. Jaydip Sen, P. Balamuralidhar, M. Girish Chandra, Harihara S. G.

    In a dynamic heterogeneous environment, such as pervasive and ubiquitous computing, context-aware adaptation is a key concept to meet the varying requirements of different users. Connectivity is an important context source that can be utilized for optimal management of diverse networking resources. Application QoS (Quality of service) is another important is

  78. Akiko Fukuhara, Fumitoshi Kaneko, Naohisa Ogawa

    The green house effect is caused by the gases which absorb infrared ray (IR) emitted by the earth. It is worthwhile if we can adjudicate on which gas causes the greenhouse effect in our class. For this purpose, one of our authors, Kaneko has designed an educational tool for testing greenhouse effect \cite{Kaneko}. This system (hereafter abbreviated PAS) is c

  79. Hong Li, Jie Liu, Jun-Qing Xia, Yi-Fu Cai

    In this paper we present the constraints on cold dark matter (CDM) isocurvature contributions to the cosmological perturbations. By employing Markov Chain Monte Carlo method (MCMC), we perform a global analysis for cosmological parameters using the latest astronomical data, such as 7-year Wilkinson Microwave Anisotropy Probe (WMAP7) observations, matter powe

  80. Jiapu Zhang, Jie Sun, Changzhi Wu

    X-ray crystallography is a powerful tool to determine the protein 3D structure. However, it is time-consuming and expensive, and not all proteins can be successfully crystallized, particularly for membrane proteins. Although nuclear magnetic resonance (NMR) spectroscopy is indeed a very powerful tool in determining the 3D structures of membrane proteins, it

  81. Chenguang Lu

    A symmetrical model of color vision, the decoding model as a new version of zone model, was introduced. The model adopts new continuous-valued logic and works in a way very similar to the way a 3-8 decoder in a numerical circuit works. By the decoding model, Young and Helmholtz&#39;s tri-pigment theory and Hering&#39;s opponent theory are unified more natura

  82. Paul S. Wesson

    Campbell&#39;s theorem enables the embedding of 4D anti-deSitter space in 5D canonical space, so a particle becomes a wave in the extra dimension, running through spacetime. This model of wave-particle duality provides a new approach to particle mass.

  83. Hanxi Li, Chunhua Shen, Qinfeng Shi

    The $\ell_1$ tracker obtains robustness by seeking a sparse representation of the tracking object via $\ell_1$ norm minimization \cite{Xue_ICCV_09_Track}. However, the high computational complexity involved in the $ \ell_1 $ tracker restricts its further applications in real time processing scenario. Hence we propose a Real Time Compressed Sensing Tracking (

  84. David Cook, Uwe Nagel

    The weak and strong Lefschetz properties are two basic properties that Artinian algebras may have. Both Lefschetz properties may vary under small perturbations or changes of the characteristic. We study these subtleties by proposing a systematic way of deforming a monomial ideal failing the weak Lefschetz property to an ideal with the same Hilbert function a

  85. Joao Caetano

    Typically, the exact ground state energy of integrable models at finite volume can be computed using two main methods: the thermodynamic Bethe ansatz approach and the lattice discretization technique. For quantum sigma models (with non-ultra local Poisson structures) the bridge between these two approaches has only been done through numerical methods. We bri

  86. Eric Brochu, Vlad M. Cora, Nando de Freitas

    We present a tutorial on Bayesian optimization, a method of finding the maximum of expensive cost functions. Bayesian optimization employs the Bayesian technique of setting a prior over the objective function and combining it with evidence to get a posterior function. This permits a utility-based selection of the next observation to make on the objective fun

  87. Ferkan Yilmaz, Mohamed-Slim Alouini

    In this paper, we introduce a generalized composite fading distribution (termed extended generalized-K (EGK)) to model the envelope and the power of the received signal in millimeter wave (60 GHz or above) and free-space optical channels. We obtain the first and the second-order statistics of the received signal envelope characterized by the EGK composite fa

  88. Giacomo Mauro D&#39;Ariano

    The experience from Quantum Information has lead us to look at Quantum Theory (QT) and the whole Physics from a different angle. The information-theoretical paradigm---&#34;It from Bit&#39;---prophesied by John Archibald Wheeler is relentlessly advancing. Recently it has been shown that QT is derivable from pure informational principles. The possibility that

  89. Ferkan Yilmaz, Mohamed-Slim Alouini

    Unified exact average capacity results for L-branch coherent diversity receivers including equal-gain combining (EGC) and maximal-ratio combining (MRC) are not known. This paper develops a novel generic framework for the capacity analysis of $L$-branch EGC/MRC over generalized fading channels. The framework is used to derive new results for the Gamma shadowe

  90. David Foster

    The Skyrme-Faddeev model is a (3+1)-dimensional model which has knotted, string-like, soliton solutions. In this paper we investigate a Skyrme-Faddeev model with an SO(3) symmetry breaking potential. We then rescale this model and take the mass to infinity. This infinite mass model is found to have compact knotted solutions. In all of the investigated massiv

  91. Katrin Gelfert, Feliks Przytycki, Michal Rams, Juan Rivera-Letelier

    We study the dimension spectrum for Lyapunov exponents for rational maps acting on the Riemann sphere and characterize it by means of the Legendre-Fenchel transform of the hidden variational pressure. This pressure is defined by means of the variational principle with respect to non-atomic invariant probability measures and is associated to certain $σ$-finit

  92. Adriano Moura, Fernanda Pereira

    We obtain a graded character formula for certain graded modules for the current algebra over a simple Lie algebra of type E6. For certain values of their highest weight, these modules were conjectured to be isomorphic to the classical limit of the corresponding minimal affinizations of the associated quantum group. We prove that this is the case under furthe

  93. Guillermo A. Lemarchand, Ernst Mayr, Carl Sagan

    During the Second Iberoamerican Graduate School on Astrobiology interesting debates, between the experts from the biological and physical backgrounds, arose about the probability of the existence of extraterrestrial intelligent beings in the universe. For this reason, it is appropriate to reproduce -for the first time in Spanish- the debate on the subject co

  94. Guillermo A. Lemarchand

    The work is divided into three sections: the first one describes the historical evolution of the main arguments presented about the plurality of inhabited worlds, from the presocratics to the birth of modern science. The second section analyzes the race to define the search for life beyond Earth as a scientific activity under a specific name. Finally, the th

  95. D. M. Gitman, A. G. Smirnov, I. V. Tyutin, B. L. Voronov

    We develop a general technique for finding self-adjoint extensions of a symmetric operator that respect a given set of its symmetries. Problems of this type naturally arise when considering two- and three-dimensional Schrödinger operators with singular potentials. The approach is based on constructing a unitary transformation diagonalizing the symmetries and

  96. Guillermo A. Lemarchand

    In this article an analysis of the fundamentals used to search for extraterrestrial artificial signals in the galaxy, which have been developing for more than five decades, is presented. It is shown that the key factor for the success of these research projects is given by the technological civilizations lifetimes. Assuming the Principle of Mediocrity, estim

  97. Han-Lin Li, Fu-Ming Liu, Guo-Liang Ma, Xin-Nian Wang

    Jet propagation is shown to produce Mach-cone-like medium excitation inside a quark-gluon plasma. However, only deflection of such medium excitation and jet shower partons by radial flow leads to double-peaked dihadron correlation in high-energy heavy-ion collisions. Dihadron correlations from harmonic flow, hot spots and dijets are studied separately within

  98. Mark Andrea A. de Cataldo, Tamas Hausel, Luca Migliorini

    We show that a natural isomorphism between the rational cohomology groups of the two zero-dimensional Hilbert schemes of $n$-points of two surfaces, the affine plane minus the axes and the cotangent bundle of an elliptic curve, exchanges the weight filtration on the first set of cohomology groups with the perverse Leray filtration associated with a natural f

  99. Tai-Lung Wu, Luisa Whittaker, Sarbajit Banerjee, G. Sambandamurthy

    Results from transport measurements in individual $W_{x}V_{1-x}O_{2}$ nanowires with varying extents of $W$ doping are presented. An abrupt thermally driven metal-insulator transition (MIT) is observed in these wires and the transition temperature decreases with increasing $W$ content at a pronounced rate of - (48-56) K/$at.%W$, suggesting a significant alte

  100. Magdalena Kobylanski

    We establish a Large Deviations Principle for stochastic processes with Lipschitz continuous oblique reflections on regular domains. The rate functional is given as the value function of a control problem and is proved to be good. The proof is based on an original viscosity solution approach. The idea consists in interpreting the probabilities as the solutio