May 2010 arXiv papers — page 19
Showing 1,801–1,900 of 5,722 papers
A. N. Omara, Sherine M. Abd El-Kader, Hussein S. Eissa, S. El-Ramly
In recent years, WLAN technology has been gaining popularity around the world with its sub standard 802.11b receiving major deployments in many indoor and outdoor environments. In this article we investigate the performance of IEEE 802.11b infrastructure networks in the lossless and lossy environments by means of a simulation study. Also, this study shows ho
Gilbert Phuah Leong Siang, Nor Azman Ismail, Pang Yee Yong
With the rapid development of computer technology, computer music has begun to appear in the laboratory. Many potential utility of computer music is gradually increasing. The purpose of this paper is attempted to analyze the possibility of integrating multimodal interaction such as vision-based hand gesture and speech interaction into musical conducting educ
Sami Halawani, Abdul Waheed Khan
Wireless Sensor Networks are basically used for gathering information needed by smart environments but they are particularly useful in unattended situations where terrain, climate and other environmental constraints may hinder in the deployment of wired/conventional networks. Unlike traditional networks, these sensor networks do not have a continuous power s
Sattar J. Aboud
In this paper, we analyze a knapsack schemes. The one is suggested by Su, which is relied on a new method entitled permutation combination method. We demonstrate that this permutation method is useless to the security of the scheme. Since the special super increasing construction, we can break this scheme employ the algorithm provided by Shamir scheme. Final
E. Jenefa JebaJothi, V. Kavitha, T. Kavitha
Routing the packets efficiently in mobile ad hoc network does not have end to end paths. Multiple copies are forwarded from the source to the destination. To deal with such networks, researches introduced flooding based routing schemes which leads to high probability of delivery. But the flooding based routing schemes suffered with contention and large delay
An Ontology-based Context Aware System for Selective Dissemination of Information in a Digital Library
cs.DLMarisa R. De Giusti, Gonzalo L. Villarreal, Agustín Vosou, Juan P. Martínez
Users of Institutional Repositories and Digital Libraries are known by their needs for very specific information about one or more subjects. To characterize users profiles and offer them new documents and resources is one of the main challenges of today's libraries. In this paper, a Selective Dissemination of Information service is described, which propo
Mustapha Bahich, Mohamed Afifi, Elmostafa Barj
In this paper we present an algorithm for optical phase evaluation based on the wavelet transform technique. The main advantage of this method is that it requires only one fringe pattern. This algorithm is based on the use of a second π/2 phase shifted fringe pattern where it is calculated via the Hilbert transform. To test its validity, the algorithm was us
C. A. Bertulani, M. Ellermann
We study in details the space-time dependence of the production of muonic, pionic, and other exotic atoms by the coherent photon exchange between nuclei at the Large Hadron Collider at CERN. We show that a multipole expansion of the electromagnetic interaction yields an useful insight of the bound-free production mechanism which has not been explored in the
Alexandre J. Chorin, Matthias Morzfeld, Xuemin Tu
Implicit particle filters for data assimilation update the particles by first choosing probabilities and then looking for particle locations that assume them, guiding the particles one by one to the high probability domain. We provide a detailed description of these filters, with illustrative examples, together with new, more general, methods for solving the
N. Paver, Riazuddin
Motivated by recent estimates of the isospin-violating process tau \to eta pi nu_tau, mostly relying on the rho and a_0 dominance of the relevant form factors near threshold, we present an assessment for the branching ratio that accounts for additional, potential, effects from the lowest radial excitations rho(1450) and a_0(1450), respectively, also lying in
R. Balbinot, I. Carusotto, A. Fabbri, A. Recati
Hawking's prediction of thermal radiation by black holes has been shown by Unruh to be expected also in condensed matter systems. We show here that in a black hole-like configuration realised in a BEC this particle creation does indeed take place and can be unambiguously identified via a characteristic pattern in the density-density correlations. This op
GLLH EM Invisible Cloak With Novel Front Branching And Without Exceed Light Speed Violation
physics.gen-phGanquan Xie, Jianhua Li, Lee Xie, Feng Xie
In this paper, we propose new Global and Local (GL) electromagnetic (EM) cloaks with distinctive class material a_{αβ}\log ^α(b_{αβ}/h) h^β(GLLH Cloak) without exceed light speed violation. The refractive index of the GLLH cloak material, $n(r)$, is large than one or equal to one. Our GLLH cloak is created by GL EM modeling and GL EM cloak inversion with sea
Antiferromagnetic Order and Bose-Einstein Condensation in Strongly-Correlated Cold-Atom Systems: Bosonic t-J Model in the Double-CP^1 Representation
cond-mat.quant-gasYuki Nakano, Takumi Ishima, Naohiro Kobayashi, Kazuhiko Sakakibara
We study the three-dimensional bosonic t-J model, i.e., the t-J model of "bosonic electrons" at finite temperatures. This model describes a system of cold bosonic atoms with two species in an optical lattice. The model is derived from the Hubbard model for very large on-site repulsive interaction between bosons of same species (hard-core nature) and
K. Wünsch, J. Vorberger, G. Gregori, D. O. Gericke
We demonstrate the abilities of elastic x-ray scattering to yield information on dense matter with multiple ion species and on the microscopic mixing in dense materials. Based on partial structure factors from ab initio simulations, a novel approach for the elastic scattering feature is applied to dense hydrogen-beryllium and hydrogen-helium mixtures. The sc
A model of homogeneous semicoherent interphase boundary for heterophase precipitates in substitution alloys under irradiation
cond-mat.mtrl-sciA. Borisenko
The model of homogeneous semicoherent interphase boundary describes the processes of absorption and thermoactivated migration of irradiation-produced inequilibrium point defects at a semicoherent boundary between a heterophase precipitate and a substitution solid solution. Within this model the kinetics of evolution of the sizes of precipitates of constant c
Re-dressing Emperor: Four Dimensional Yang-Mills Theory, Gauge Invariant Mass And Fluctuating Three Branes
hep-thAntti J. Niemi, Sergey Slizovskiy
We consider the coupling between four dimensional Yang-Mills field and a three brane that fluctuates into higher dimensions. For this we interpret the Yang-Mills theory as a higher dimensional bulk gravity theory with dynamics that is governed by the Einstein action, and with a metric tensor constructed from the gauge field in a manner that displays the orig
T. Banerjee, W. G. van der Wiel, R. Jansen
Organic and carbon-based materials are attractive for spintronics because their small spin-orbit coupling and low hyperfine interaction is expected to give rise to large spin-relaxation times. However, the corresponding spin-relaxation length is not necessarily large when transport is via weakly interacting molecular orbitals. Here we use graphite as a model
N. Mohan Kumar, A. P. Rao, G. V. Ravindra
We show that for a smooth hypersurface $X\subset \bbP^n$ of degree at least 2, there exist arithmetically Cohen-Macaulay (ACM) codimension two subvarieties $Y\subset X$ which are not an intersection $X\cap{S}$ for a codimension two subvariety $S\subset\bbP^n$. We also show there exist $Y\subset X$ as above for which the normal bundle sequence for the inclusi
Arithmetically Cohen-Macaulay Bundles on complete intersection varieties of sufficiently high multidegree
math.AGJishnu Biswas, G. V. Ravindra
Recently it has been proved that any arithmetically Cohen-Macaulay (ACM) bundle of rank two on a general, smooth hypersurface of degree at least three and dimension at least four is a sum of line bundles. When the dimension of the hypersurface is three, a similar result is true provided the degree of the hypersurface is at least six. We extend these results
Richard McKinley
This paper explores the connection between two central results in the proof theory of classical logic: Gentzen's cut-elimination for the sequent calculus and Herbrands "fundamental theorem". Starting from Miller's expansion-tree-proofs, a highly structured way presentation of Herbrand's theorem, we define a calculus of weakening-free proo
David A. Adams, Leonard M. Sander, Robert M. Ziff
In many dynamical systems there is a large separation of time scales between typical events and "rare" events which can be the cases of interest. Rare-event rates are quite difficult to compute numerically, but they are of considerable practical importance in many fields: for example transition times in chemical physics and extinction times in epidem
G. V. Ravindra
We prove that any arithmetically Gorenstein curve on a smooth, general hypersurface $X\subset \bbP^{4}$ of degree at least 6, is a complete intersection. This gives a characterisation of complete intersection curves on general type hypersurfaces in $\bbP^4$. We also verify that certain 1-cycles on a general quintic hypersurface are non-trivial elements of th
Alan P. Boss, Sandra A. Keiser
The short-lived radioisotope $^{60}$Fe requires production in a core collapse supernova or AGB star immediately before its incorporation into the earliest solar system solids. Shock waves from a somewhat distant supernova, or a relatively nearby AGB star, have the right speeds to simultaneously trigger the collapse of a dense molecular cloud core and to inje
Barotropic Magnetohydrodynamics as a Four Function Field Theory with Non-Trivial Topology and Aharonov-Bohm Effects
physics.plasm-phAsher Yahalom
Variational principles for magnetohydrodynamics were introduced by previous authors both in Lagrangian and Eulerian form. In previous works [1] Yahalom & Lynden-Bell and later Yahalom [2] introduced a simpler Eulerian variational principle from which all the relevant equations of Magnetohydrodynamics can be derived. The variational principles were given in t
Dzyaloshinsky-Moriya interaction and long life time of the spin state in the Cu$_3$ triangular spin cluster by inelastic neutron scattering measurements
cond-mat.otherKazuki Iida, Yiming Qiu, Taku J Sato
Inelastic neutron scattering (INS) experiments have been performed on the Cu$_3$ triangular molecular nanomagnet using powder samples. In the medium resolution INS spectrum measured, there are two peaks at $\hbarω=0.5$ and 0.6 meV. Comparing the observed $Q$ dependences of these peaks with calculations, these two INS peaks originate from the Cu$_3$ cluster.
A. Zúñiga-Segundo, J. M. Vargas-Martínez, R. Juárez-Amaro, H. Moya-Cessa
We show that in the trapped ion-laser interaction all the regimes may be considered analytically. We may solve not only for different laser intensities, but also away from resonance and from the Lamb-Dicke regime. It is found a dispersive Hamiltonian for the high intensity regime, that, being diagonal, its evolution operator may be easily calculated.
The su(1,1) Dynamical Algebra for the Generalized MICZ-Kepler Problem from the Schrödinger Factorization
quant-phM. Salazar-Ramirez, D. Martinez, V. D. Granados R. D. Mota
We apply the Schrödinger factorization to construct the generators of the dynamical algebra $su(1,1)$ for the radial equation of the generalized MICZ-Kepler problem.
C. Wetterich
Non-commutative quantum physics at the atom scale can arise from coarse graining of a classical statistical ensemble at the Planck scale. Position and momentum of an isolated particle are classical observables which remain computable in terms of the coarse grained information. However, the commuting classical product of position and momentum observables is n
The su(1,1) dynamical algebra from the Schrödinger ladder operators for N-dimensional systems: hydrogen atom, Mie-type potential, harmonic oscillator and pseudo-harmonic oscillator
quant-phD. Martinez, J. C. Flores-Urbina, R. D. Mota, V. D. Granados
We apply the Schrödinger factorization to construct the ladder operators for hydrogen atom, Mie-type potential, harmonic oscillator and pseudo-harmonic oscillator in arbitrary dimensions. By generalizing these operators we show that the dynamical algebra for these problems is the $su(1,1)$ Lie algebra.
J. A. Scarpaci, M. Fallot, D. Lacroix, M. Assie
In this Letter, we report on alpha particle emission through the nuclear break-up in the reaction 40Ca on a 40Ca target at 50A MeV. It is observed that, similarly to nucleons, alpha particles can be emitted to the continuum with very specific angular distribution during the reaction. The alpha particle properties can be understood as resulting from an alpha
H. J. van Eerten, Z. Meliani, R. A. M. J. Wijers, R. Keppens
The conventional derivation of the gamma-ray burst afterglow jet break time uses only the blast wave fluid Lorentz factor and therefore leads to an achromatic break. We show that in general gamma-ray burst afterglow jet breaks are chromatic across the self-absorption break. Depending on circumstances, the radio jet break may be postponed significantly. Using
Intergrain effects in the AC susceptibility of polycrystalline LaFeAsO_{0.94}F_{0.06}: comparison with cuprate superconductors
cond-mat.supr-conG. Bonsignore, A. Agliolo Gallitto M. Li Vigni, J. L. Luo, G. F. Chen
The AC susceptibility at zero DC magnetic field of a polycrystalline sample of LaFeAsO_{0.94}F_{0.06} (T_c = 24 K) has been investigated as a function of the temperature, the amplitude of the AC magnetic field (in the range Hac = 0.003 - 4 Oe) and the frequency (in the range f = 10 kHz - 100 kHz). The temperature dependence of the AC susceptibility exhibits
G. Kleine Büning, J. Will, W. Ertmer, C. Klempt
We report on a slow guided atom laser beam outcoupled from a Bose-Einstein condensate of 87Rb atoms in a hybrid trap. The acceleration of the atom laser beam can be controlled by compensating the gravitational acceleration and we reach residual accelerations as low as 0.0027 g. The outcoupling mechanism allows for the production of a constant flux of 4.5x10^
Benoit Daniel, William H. Meeks, Harold Rosenberg
We prove some half-space theorems for minimal surfaces in the Heisenberg group Nil_3 and the Lie group Sol_3 endowed with their left-invariant Riemannian metrics. If S is a properly immersed minimal surface in Nil_3 that lies on one side of some entire minimal graph G, then S is the image of G by a vertical translation. If S is a properly immersed minimal su
Tulasi Ram Reddy A
Rotor Router models were first introduced by James Propp in 2002. A recurrent Rotor configuration is the one in which every state is visited infinitely often. In this project we investigated whether there is a recurrent Rotor configuration in Z^d (d>2).
Markus Bier, Rene van Roij, Marjolein Dijkstra
Phase diagrams of binary mixtures of oppositely charged colloids are calculated theoretically. The proposed mean-field-like formalism interpolates between the limits of a hard-sphere system at high temperatures and the colloidal crystals which minimize Madelung-like energy sums at low temperatures. Comparison with computer simulations of an equimolar mixture
Christoph Bergbauer
I review various aspects of Feynman integrals, regularization and renormalization. Following Bloch, I focus on a linear algebraic approach to the Feynman rules, and I try to bring together several renormalization methods found in the literature from a unifying point of view, using resolutions of singularities. In the second part of the paper, I briefly sketc
Conor A. Nixon, Richard K. Achterberg, Paul N. Romani, Mark Allen
The flybys of Jupiter by the Voyager spacecraft in 1979, and over two decades later by Cassini in 2000, have provided us with unique datasets from two different epochs, allowing the investigation of seasonal change in the atmosphere. In this paper we model zonal averages of thermal infrared spectra from the two instruments, Voyager 1 IRIS and Cassini CIRS, t
S. G. Parsons, T. R. Marsh, C. M. Copperwheat, V. S. Dhillon
We present high speed ULTRACAM photometry of the eclipsing post common envelope binaries DE CVn, GK Vir, NN Ser, QS Vir, RR Cae, RX J2130.6+4710, SDSS 0110+1326 and SDSS 0303+0054 and use these data to measure precise mid-eclipse times in order to detect any period variations. We detect a large (~ 250 sec) departure from linearity in the eclipse times of QS
Tadahiro Oh, Jeremy Quastel, Benedek Valko
We consider the family of interpolation measures of Gibbs measures and white noise given by $$dQ_{0,\b}^{(p)} = Z_\b^{-1} \ind_{{\int_{\T} u^2\le K\b^{-1/2}\}} e^{-\int_{\T} u^2 +\b \int u^p} dP_{0,\b}$$ where $P_{0, \b}$ is the Wiener measure on the circle, with variance $β^{-1}$, conditioned to have mean zero. It is shown that as $β\to 0$, $Q_0^β$ converge
Baojun Bian, Sheng Miao, Harry Zheng
In this paper we prove that there exists a smooth classical solution to the HJB equation for a large class of constrained problems with utility functions that are not necessarily differentiable or strictly concave. The value function is smooth if admissible controls satisfy an integrability condition or if it is continuous on the closure of its domain. The k
Keith A. Olive
Four lectures on Big Bang cosmology, including microwave background radiation, Big Bang nucleosynthesis, dark matter, inflation, and baryogenesis.
M. Klasen
We present the first NLO QCD analysis of single-diffractive dijet production in proton-antiproton collisions. By comparing the ratio of single- and non-diffractive cross sections to data from the Tevatron, the rapidity-gap survival probability is determined as a function of the momentum fraction of the parton in the antiproton. Assuming Regge factorization,
Marijan Ribarič, Luka Šušteršič
For the first time a method is devised for non-iterative modeling of motion of a radiating, electrified pointlike mass that has an internal structure. New, supplementary kinetic constants of accelerated charged particles are defined, that can be assessed by analysis of their trajectories in an accelerator.
The non-polynomial conservation laws and integrability analysis of generalized Riemann type hydrodynamical equations
nlin.SIZiemowit Popowicz, Anatoliy K. Prykarpatsky
Based on the gradient-holonomic algorithm we analyze the integrability property of the generalized hydrodynamical Riemann type equation $%D_{t}^{N}u=0$ for arbitrary $N\in \mathbb{Z}_{+}.$ The infinite hierarchies of polynomial and non-polynomial conservation laws, both dispersive and dispersionless are constructed. Special attention is paid to the cases $%N
R. Getko
The sunspot area fluctuations for the northern and the southern hemispheres of the Sun over the epoch of 12 cycles (12-23) are investigated. Because of the asymmetry of their probability distributions, the positive and the negative fluctuations are considered separately. The auto-correlation analysis of them shows three quasi-periodicities at 10, 17 and 23 s
A. Kawka, S. Vennes, T. R. Vaccaro
We show that the extremely low-mass white dwarf NLTT 11748 (0.17 M_sun) is in a close binary with a fainter companion. We obtained a series of radial velocity measurements of the low-mass white dwarf using the Halpha core and determined an orbital period of 5.64 hours. The velocity semi-amplitude (K=274.8 km/s) and orbital period imply that it is a degenerat
Nazim I. Mahmudov
his paper deals with approximating properties of the newly defined $q$-generalization of the Szász operators in the case $q>1$. Quantitative estimates of the convergence in the polynomial weighted spaces and the Voronovskaja's theorem are given. In particular, it is proved that the rate of approximation by the $q$-Szász operators ($q>1$) is of order $q^{
Arabinda Haldar, K. G. Suresh, A. K. Nigam
For the first time, we find that the dynamic antiferromagnetic phase present in CeFe2 gets stabilized with Ga and Si substitutions. We find that phenomena such as strain-induced first order jumps in the magnetization curves, asymmetry between the M-H curves during the increasing and decreasing field cycles, the envelope curve being inside the virgin curve, o
S. Castiñeira-Ibáñez, V. Romero-García, J. V. Sánchez-Pérez, L. M. Garcia-Raffi
Research into properties of heterogeneous artificial materials, consisting of arrangements of rigid scatterers embedded in a medium with different elastic properties, has been intense throughout last two decades. The capability to prevent the transmission of waves in predetermined bands of frequencies -called bandgaps- becomes one of the most interesting pro
Arabinda Haldar, Niraj K. Singh, Ya. Mudryk, Ajaya K. Nayak
The magnetic and magnetostructural properties of the polycrystalline Ce(Fe0.975Ga0.025)2 have been investigated as a function of temperature and magnetic field. In Ce(Fe0.975Ga0.025)2 the magnetic transition from antiferromagnetic (AFM) to ferromagnetic state (FM) is accompanied by a structural transformation from rhombohedral to cubic structure. Phase coexi
Brillouin amplification in phase coherent transfer of optical frequencies over 480 km fiber
physics.opticsO. Terra, G. Grosche, H. Schnatz
We describe the use of fiber Brillouin amplification (FBA) for the coherent transmission of optical frequencies over a 480 km long optical fiber link. FBA uses the transmission fiber itself for efficient, bi-directional coherent amplification of weak signals with pump powers around 30 mW. In a test setup we measured the gain and the achievable signal-to-nois
The Herschel view of star formation in the Rosette molecular cloud under the influence of NGC 2244
astro-ph.GAN. Schneider, F. Motte, S. Bontemps, M. Hennemann
The Rosette molecular cloud is promoted as the archetype of a triggered star-formation site. This is mainly due to its morphology, because the central OB cluster NGC 2244 has blown a circular-shaped cavity into the cloud and the expanding HII-region now interacts with the cloud. Studying the spatial distribution of the different evolutionary states of all st
Elements of mathematical foundations for a numerical approach for weakly random homogenization problems
math.APArnaud Anantharaman, Claude Le Bris
This work is a follow-up to our previous work "A numerical approach related to defect-type theories for some weakly random problems in homogenization" (preprint available on this archive). It extends and complements, both theoretically and experimentally, the results presented there. Under consideration is the homogenization of a model of a weakly ra
R. Getko
I study the sunspot area fluctuations over the epoch of 12 solar cycles (12-23). Lately, I found three significant quasi-periodicities at 10, 17 and 23 solar rotations, but two longer periods could be treated as subharmonics of the 10-rotation period. Thus, I search this period during the low- and the high-activity periods of each solar cycles. Because of th
Insights on the Milky Way bulge formation from the correlations between kinematics and metallicity
astro-ph.GAC. Babusiaux, A. Gomez, V. Hill, F. Royer
Two main scenarios for the formation of the Galactic bulge are invoked, the first one through gravitational collapse or hierarchical merging of subclumps, the second through secular evolution of the Galactic disc. We aim to constrain the formation of the Galactic bulge through studies of the correlation between kinematics and metallicities in Baade's Win
Benjamin Depardon, Eddy Caron, Frédéric Desprez, Jérémy Blaizot
The work presented in this paper aims at restricting the input parameter values of the semi-analytical model used in GALICS and MOMAF, so as to derive which parameters influence the most the results, e.g., star formation, feedback and halo recycling efficiencies, etc. Our approach is to proceed empirically: we run lots of simulations and derive the correct r
Instabilities in associative memory model with synaptic depression and switching phenomena among attractors
cond-mat.dis-nnYosuke Otsubo, Kenji Nagata, Masafumi Oizumi, Masato Okada
We investigated how the stability of macroscopic states in the associative memory model is affected by synaptic depression. To this model, we applied the dynamical mean-field theory, which has recently been developed in stochastic neural network models with synaptic depression. By introducing a sublattice method, we derived macroscopic equations for firing s
B. Vandenbussche, B. Sibthorpe, B. Acke, E. Pantin
We obtained Herschel PACS and SPIRE images of the thermal emission of the debris disk around the A5V star β Pic. The disk is well resolved in the PACS filters at 70, 100, and 160 μm. The surface brightness profiles between 70 and 160 μm show no significant asymmetries along the disk, and are compatible with 90% of the emission between 70 and 160 μm originati
Horia D. Cornean, Celine Gianesello, Valentin Zagrebnov
We construct a non-equilibrium steady state and calculate the corresponding current for a mesoscopic Fermi system in the partition-free setting. To this end we study a small sample coupled to a finite number of semi-infinite leads. Initially, the whole system of quasi-free fermions is in a grand canonical equilibrium state. At t = 0 we turn on a potential bi
Bulat N. Khabibullin
A conjecture concerning some pairs of interfering estimates for some integrals is formulated in three equivalent versions. Its importance for the the Paley problem for plurisubharmonic functions and for certain classes of extremal problems for entire functions of several variables is declared.
Well-localized edge states in two-dimensional topological insulators: ultrathin Bi films
cond-mat.mtrl-sciM. Wada, S. Murakami, F. Freimuth, G. Bihlmayer
We theoretically study the generic behavior of the penetration depth of the edge states in two-dimensional quantum spin Hall systems. We found that the momentum-space width of the edge-state dispersion scales with the inverse of the penetration depth. As an example of well-localized edge states, we take the Bi(111) ultrathin film. Its edge states are found t
G. J. Qiao, R. X. Xu, Y. J. Du
Anomalous X-ray Pulsars and Soft Gamma-Ray Repeaters have been generally recognized as neutron stars with super strong magnetic fields, namely "magnetars". The "magnetars" manifest that the luminosity in X-ray band are larger than the rotational energy loss rate, i.e. $L_{X}>\dot {E}_{\rm rot}$, and then the radiation energy is coming from th
A numerical approach related to defect-type theories for some weakly random problems in homogenization
math.APArnaud Anantharaman, Claude Le Bris
We present in this paper an approach for computing the homogenized behavior of a medium that is a small random perturbation of a periodic reference material. The random perturbation we consider is, in a sense made precise in our work, a rare event at the microscopic level. It however affects the macroscopic properties of the material, and we indeed provide a
Patrick Cattiaux, Arnaud Guillin, Liming Wu
We give here a simple proof of weighted logarithmic Sobolev inequality, for example for Cauchy type measures, with optimal weight, sharpening results of Bobkov-Ledoux. Some consequences are also discussed.
Objective Climate Model Predictions Using Jeffreys' Prior: the General Multivariate Normal Case
physics.ao-phStephen Jewson, Dan Rowlands, Myles Allen
Objective probabilistic forecasts of future climate that include parameter uncertainty can be made by using the Bayesian prediction integral with the prior set to Jeffreys' Prior. The calculations involved in determining the prior can then be simplified by making parametric assumptions about the distribution of the output from the climate model. The most
Daciberg Lima Gonçalves, John Guaschi
We determine the lower central and derived series of the n-string braid groups B_n(RP^2) of the real projective plane. We are motivated in part by the study of Fadell-Neuwirth short exact sequences, but the problem is interesting in its own right. For n=1,2, B_n(RP^2) is finite and its lower central and derived series are known. If n>2 (resp. n>4), we show t
I. M. Khaymovich, M. A. Silaev
We investigate a magnetic susceptibility of vortices in the B phase of multicomponent triplet superfluid $^3$He focusing on a contribution of bound fermionic states localized within vortex cores. Several order parameter configurations relevant to different types of quantized vortices in $^3$He B are considered. It is shown quite generally that an ac magnetic
W. Wang, S. L. Zhang, Z. X. Tian, W. Xiao
Using first-principles density functional theory method, we have investigated the distribution and magnetism of doped Mn atoms in the vicinity of the 3 (112) grain boundary in Ge. We find that at low concentration, the substitutional sites are energetically favorable over the interstitial ones for Mn. The binding energy of Mn varies with lattice sites in the
Nicolas Perry, Richard J. B. Stein, Robert Vergnieux, Cabot Laurent
This study is based on Roman wooden force pumps. It appears that they were used in small numbers to raise water from wells, and more commonly as portable pumps to fight fires. The force pump is attributed to Ctesibius of Alexandria (fl. c.270 B.C.). The earlier examples were made in bronze, but the original design was cleverly re-engineered in Roman times to
Nabil Hathout
This paper describes in details the first version of Morphonette, a new French morphological resource and a new radically lexeme-based method of morphological analysis. This research is grounded in a paradigmatic conception of derivational morphology where the morphological structure is a structure of the entire lexicon and not one of the individual words it
P. Venkatakrishnan, Sanjiv Kumar Tiwari
The equilibrium structure of sunspots depends critically on its magnetic topology and is dominated by magnetic forces. Tension force is one component of the Lorentz force which balances the gradient of magnetic pressure in force-free configurations. We employ the tension term of the Lorentz force to clarify the structure of sunspot features like penumbral fi
L. Turban
We study a one-dimensional random walk with memory in which the step lengths to the left and to the right evolve at each step in order to reduce the wandering of the walker. The feedback is quite efficient and lead to a non-diffusive walk. The time evolution of the displacement is given by an equivalent Markovian dynamical process. The probability density fo
The perturbative invariants of rational homology 3-spheres can be recovered from the LMO invariant
math.GTTakahito Kuriya, Thang T. Q. Le, Tomotada Ohtsuki
We show that the perturbative ${\frak g}$ invariant of rational homology 3-spheres can be recovered from the LMO invariant for any simple Lie algebra ${\frak g}$, i.e, the LMO invariant is universal among the perturbative invariants. This universality was conjectured in [25]. Since the perturbative invariants dominate the quantum invariants of integral homol
Sparsh Navin
The PYTHIA program can be used to generate high-energy-physics 'events' with sets of outgoing particles produced in the interactions between two incoming particles. The objective is to provide a representation, as accurate as possible, of event properties in a wide range of reactions. One such reaction, that is not well understood is Diffraction. Amo
Kay Kinoshita
The B-factories have successfully exploited the unique advantages of the Upsilon(4S) resonance to study many aspects of Bd and Bu mesons. The Upsilon(10860) (aka Upsilon(5S)) resonance, which is above mass threshold for the Bs and shares many of the same advantages, has been relatively unexplored. The Belle experiment has collected more than 120 fb-1 at the
Yu-Lin Lin
In this work, we give a perturbation theorem for strong polynomial solutions to the zero surface tension Hele-Shaw equation driven by injection or suction, so called the Polubarinova-Galin equation. This theorem enables us to explore properties of solutions with initial functions close to but are not polynomial. Applications of this theorem are given in the
Effect of Heterogeneous Mixing and Vaccination on the Dynamics of Anthelmintic Resistance: A Nested Model
q-bio.PELorenzo Sabatelli
Anthelmintic resistance is a major threat to current measures for helminth control in humans and animals. The introduction of anthelmintic vaccines, as a complement to or replacement for drug treatments, has been advocated as a preventive measure. Here, a computer-based simulation, tracking the dynamics of hosts, parasites and parasite-genes, shows that, dep
Modeling Multi-Wavelength Stellar Astrometry. I. SIM Lite Observations of Interacting Binaries
astro-ph.SRJeffrey L. Coughlin, Dawn M. Gelino, Thomas E. Harrison, D. W. Hoard
Interacting binaries consist of a secondary star which fills or is very close to filling its Roche lobe, resulting in accretion onto the primary star, which is often, but not always, a compact object. In many cases, the primary star, secondary star, and the accretion disk can all be significant sources of luminosity. SIM Lite will only measure the photocente
Completeness II: A signal-to-noise approach for completeness estimators applied to galaxy magnitude-redshift surveys
astro-ph.COLuis Teodoro, Russell Johnston, Martin Hendry
This is the second paper in our completeness series which addresses some of the issues raised in the previous article by Johnston, Teodoro & Hendry (2007) in which we developed statistical tests for assessing the completeness in apparent magnitude of magnitude-redshift surveys defined by two flux limits. The statistics, Tc and Tv, associated with these tests
The electronic structure and dipole moment of charybdotoxin, a scorpion venom peptide with K+ channel blocking activity
q-bio.BMFabio Pichierri
The electronic structure of charybdotoxin (ChTX), a scorpion venom peptide that is known to act as a potassium channel blocker, is investigated with the aid of quantum mechanical calculations. The dipole moment vector (145 D) of ChTX can be stirred by the full length KcsA potassium channel's macrodipole (403 D) thereby assuming the proper orientation bef
Sukanta Deb, Harinder P. Singh, T. R. Seshadri, Ranjan Gupta
We present a CCD photometric study of the star with ASAS ID 134738 + 0410.1 using V band observations obtained from the $IUCAA$ Girawali Observatory (IGO) 2-metre telescope, India. The star was selected from the $δ$ Scuti database of All Sky Automated Survey (ASAS) (Pojmanski 2002). Our analysis reveals that the star is not a $δ$ Scuti variable but is in fac
Markus Hegland, Bernd Hofmann
Based on the variable Hilbert scale interpolation inequality bounds for the error of regularisation methods are derived under range inclusions. In this context, new formulae for the modulus of continuity of the inverse of bounded operators with non-closed range are given. Even if one can show the equivalence of this approach to the version used previously in
John Andersson, Henrik Shahgholian, Georg S. Weiss
In this paper we are concerned with singular points of solutions to the {\it unstable} free boundary problem $$ Δu = - χ_{\{u>0\}} \qquad \hbox{in} B_1. $$ The problem arises in applications such as solid combustion, composite membranes, climatology and fluid dynamics. It is known that solutions to the above problem may exhibit singularities - that is points
Alexander Punnoose
Renormalization group equations in a two-valley system with valley-splitting and intervalley scattering are derived in the presence of spin-splitting induced by a parallel magnetic field. The relevant amplitudes in different regimes set by the relative strengths of the spin and valley splittings and the intervalley scattering rate are identified. The range o
Anomalous structure in the single particle spectrum of the fractional quantum Hall effect
cond-mat.mes-hallO. E. Dial, R. C. Ashoori, L. N. Pfeiffer, K. W. West
The two-dimensional electron system (2DES) is a unique laboratory for the physics of interacting particles. Application of a large magnetic field produces massively degenerate quantum levels known as Landau levels. Within a Landau level the kinetic energy of the electrons is suppressed, and electron-electron interactions set the only energy scale. Coulomb in
Runliang Lin, Hua Peng, Manuel Manas
Based on the eigenfunction symmetry constraint of the q-deformed modified KP hierarchy, a q-deformed mKP hierarchy with self-consistent sources ($q$-mKPHSCSs) is constructed. The q-mKPHSCSs contains two types of q-deformed mKP equation with self-consistent sources. By combination of the dressing method and the method of variation of constants, a generalized
Enrique Torres-Giese
We consider ordered tuples in finite groups generating nilpotent subgroups. Given an integer $q$ we consider the poset of nilpotent subgroups of class less than $q$ and its corresponding coset poset. These posets give rise to a family of finite Dirichlet series parametrized by the nilpotency class of the subgroups, which in turn reflect probabilistic and top
Naor Movshovitz, Peter Bodenheimer, Morris Podolak, Jack J. Lissauer
Numerical simulations, based on the core-nucleated accretion model, are presented for the formation of Jupiter at 5.2 AU in 3 primordial disks with three different assumed values of the surface density of solid particles. The grain opacities in the envelope of the protoplanet are computed using a detailed model that includes settling and coagulation of grain
Improved OMP Approach to Sparse Multi-path Channel Estimation via Adaptive Inter-atom Interference Mitigation
cs.ITRuiming Yang, Qun Wan, Yipeng Liu, Wanlin Yang
Since most components of sparse multi-path channel (SMPC) are zero, impulse response of SMPC can be recovered from a short training sequence. Though the ordinary orthogonal matching pursuit (OMP) algorithm provides a very fast implementation of SMPC estimation, it suffers from inter-atom interference (IAI), especially in the case of SMPC with a large delay s
Yanwu Xie, Christopher Bell, Takeaki Yajima, Yasuyuki Hikita
Biased conducting-tip atomic force microscopy (AFM) has been shown to write and erase nanoscale metallic lines at the LaAlO3/SrTiO3 interface. Using various AFM modes, we show the mechanism of conductivity switching is the writing of surface charge. These charges are stably deposited on a wide range of LaAlO3 thicknesses, including bulk crystals. A strong as
Chantal David, Jie Wu
Let $E$ be an elliptic curve over $\F_p$ without complex multiplication, and for each prime $p$ of good reduction, let $n_E(p) = | E(\F_p) |$. Let $Q_{E,b}(x)$ be the number of primes $p \leq x$ such that $b^{n_E(p)} \equiv b\,({\rm mod}\,n_E(p))$, and $π_{E, b}^{\rm pseu}(x)$ be the number of {\it compositive} $n_E(p)$ such that $b^{n_E(p)} \equiv b\,({\rm
Comment on "Quantum Criticality and Nodal Superconductivity in the FeAs-Based Superconductor KFe$_2$As$_2$"
cond-mat.supr-conTaichi Terashima, Motoi Kimata, Nobuyuki Kurita, Hidetaka Satsukawa
In a recent Letter [J. K. Dong et al., Phys. Rev. Lett. 104, 087005 (2010)], Dong \textit{et al}. have observed a $T^{1.5}$ dependence of resistivity $ρ$ in KFe$_2$As$_2$ at the upper critical field $B_{c2}$ = 5 T parallel to the c axis and have suggested the existence of a field-induced quantum critical point (QCP) at $B_{c2}$. In this comment, we argue tha
Highly anisotropic resistivities in the double-exchange model for strained manganites
cond-mat.str-elShuai Dong, Seiji Yunoki, Xiaotian Zhang, Cengiz Sen
The highly anisotropic resistivities in strained manganites are theoretically studied using the two-orbital double-exchange model. At the nanoscale, the anisotropic double-exchange and Jahn-Teller distortions are found to be responsible for the robust anisotropic resistivities observed here via Monte Carlo simulations. An unbalanced in the population of orbi
G. S. Mathews, W. R. F. Dent, J. P. Williams, C. D. Howard
Context - Circumstellar discs are ubiquitous around young stars, but rapidly dissipate their gas and dust on timescales of a few Myr. The Herschel space observatory allows for the study of the warm disc atmosphere, using far-infrared spectroscopy to measure gas content and excitation conditions, and far-IR photometry to constrain the dust distribution. Aims
A renormalization group study of the three-color Ashkin-Teller model on a Wheatstone hierarchical lattice
cond-mat.stat-mechR. Teodoro, C. G. Bezerra, A. M. Mariz, F. A. da Costa
We have investigated the three-color Ashkin-Teller model (3AT), on the Wheatstone bridge hierarchical lattice, by means of a Migdal-Kadanoff renormalization group approach. We have obtained the exact recursion relations for the renormalized couplings, which have been used to investigate the phase diagram and to study the corresponding critical points. The ph
Michael Doebeli, Iaroslav Ispolatov
Evolutionary branching points are a paradigmatic feature of adaptive dynamics, because they are potential starting points for adaptive diversification. The antithesis to evolutionary branching points are Continuously stable strategies (CSS's), which are convergent stable and evolutionarily stable equilibrium points of the adaptive dynamics and hence are
Marco Astorino
The expectation value of Wilson loop operators in three-dimensional SO(N) Chern-Simons gauge theory gives a known knot invariant: the Kauffman polynomial. Here this result is derived, at the first order, via a simple variational method. With the same procedure the skein relation for Sp(N) are also obtained. Jones polynomial arises as special cases: Sp(2), SO
Valeriu Moldoveanu, Andrei Manolescu, Vidar Gudmundsson
Time-dependent transport through two capacitively coupled quantum dots is studied in the framework of the generalized master equation. The Coulomb interaction is included within the exact diagonalization method. Each dot is connected to two leads at different times, such that a steady state is established in one dot before the coupling of the other dot to it
Runge-Kutta methods for third order weak approximation of SDEs with multidimensional additive noise
math.NAKristian Debrabant
A new class of third order Runge-Kutta methods for stochastic differential equations with additive noise is introduced. In contrast to Platen's method, which to the knowledge of the author has been up to now the only known third order Runge-Kutta scheme for weak approximation, the new class of methods affords less random variable evaluations and is also