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61.
We investigate transverse electromagnetic waves propagating in a plasma influenced by the gravitational field of the Reissner–Nordström black hole. Applying 3+1 spacetime split we reformulate the relativistic two-fluid equations to take account of gravitational effects due to the event horizon and describe the set of simultaneous linear equations for the perturbations. Using a local approximation we investigate the one-dimensional radial propagation of Alfvén and high frequency electromagnetic waves. We derive the dispersion relation for these waves and solve it for the wave number k numerically. 相似文献
62.
F. Ta?k?n 《International Journal of Theoretical Physics》2009,48(4):1142-1149
The bound-state solutions of the Dirac equation for the Manning-Rosen potential are presented approximately for arbitrary
spin-orbit quantum number κ. The energy eigenvalues and corresponding two-component spinors of the two Dirac particles are obtained in the closed form
by using the framework of the spin symmetry and pseudospin symmetry concept. Two special cases κ=±1 and the Hulthén potential are briefly investigated. 相似文献
63.
研究了杨辉三角中的D av id星恒等式,给出了n阶星恒等式的定义,证明了n(n 3)阶星恒等式的存在性,并且给出了构造n阶星恒等式的方法. 相似文献
64.
We investigate transverse electromagnetic waves propagating in a plasma influenced by the gravitational field of the Schwarzschild-de
Sitter black hole. Applying 3+1 spacetime split we derive the relativistic two-fluid equations to take account of gravitational
effects due to the event horizon and describe the set of simultaneous linear equations for the perturbations. We use a local
approximation to investigate the one-dimensional radial propagation of Alfvén and high frequency electromagnetic waves. We
derive the dispersion relation for these waves and solve it for the wave number k numerically. 相似文献
65.
We introduce the notion of -pair of a proper subgroup of a finite group and give necessary and sufficient conditions for supersolvability and nilpotence of a finite group. As application, we give a proof to a recent open problem of Skiba in the unsolved problems in group theory. 相似文献
66.
I. Hellmann G.S. Zakharova C. Täschner B. Büchner 《Journal of magnetism and magnetic materials》2010,322(7):878-881
V3O7·H2O nanobelts were prepared by a hydrothermal method at 190 °C using V2O5·nH2O gel and H2C2O4·2H2O as starting agents. The obtained nanobelts have diameters ranging from 40 to 70 nm with lengths up to several micrometers. Measurements of the static magnetic susceptibility and the specific heat show a discontinuous phase transition at around T=145 K, which separates two regions of paramagnetic behavior. 相似文献
67.
Increasingly large volumes of space–time data are collected everywhere by mobile computing applications, and in many of these cases, temporal data are obtained by registering events, for example, telecommunication or Web traffic data. Having both the spatial and temporal dimensions adds substantial complexity to data analysis and inference tasks. The computational complexity increases rapidly for fitting Bayesian hierarchical models, as such a task involves repeated inversion of large matrices. The primary focus of this paper is on developing space–time autoregressive models under the hierarchical Bayesian setup. To handle large data sets, a recently developed Gaussian predictive process approximation method is extended to include autoregressive terms of latent space–time processes. Specifically, a space–time autoregressive process, supported on a set of a smaller number of knot locations, is spatially interpolated to approximate the original space–time process. The resulting model is specified within a hierarchical Bayesian framework, and Markov chain Monte Carlo techniques are used to make inference. The proposed model is applied for analysing the daily maximum 8‐h average ground level ozone concentration data from 1997 to 2006 from a large study region in the Eastern United States. The developed methods allow accurate spatial prediction of a temporally aggregated ozone summary, known as the primary ozone standard, along with its uncertainty, at any unmonitored location during the study period. Trends in spatial patterns of many features of the posterior predictive distribution of the primary standard, such as the probability of noncompliance with respect to the standard, are obtained and illustrated. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
68.
Manju Pruthi 《Proceedings Mathematical Sciences》2001,111(4):371-379
In this paper explicit expressions ofm + 1 idempotents in the ring
are given. Cyclic codes of length 2
m
over the finite fieldF
q, of odd characteristic, are defined in terms of their generator polynomials. The exact minimum distance and the dimension
of the codes are obtained. 相似文献
69.
70.
The Turán number is the maximum number of edges in any -vertex graph that does not contain a subgraph isomorphic to . A wheel is a graph on vertices obtained from a by adding one vertex and making adjacent to all vertices of the . We obtain two exact values for small wheels: Given that is already known, this paper completes the spectrum for all wheels up to 7 vertices. In addition, we present the construction which gives us the lower bound in general case. 相似文献