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排序方式: 共有3058条查询结果,搜索用时 31 毫秒
41.
42.
Given n samples(viewed as an n-tuple) of a γ-regular discrete distribution π,in this article the authors concern with the weighted and unweighted graphs induced by the n samples. They first prove a series of SLLN results(of Dvoretzky-Erd¨os’ type). Then they show that the vertex weights of the graphs under investigation obey asymptotically power law distributions with exponent 1 + γ. They also give a conjecture that the degrees of unweighted graphs would exhibit asymptotically power law distribu... 相似文献
43.
In this paper we establish the existence of the minimal large positive solution for a general class of nonlinear cooperative systems including the simplest prototype of García-Melián et al. (2016). Precisely, based on the existence of a large positive supersolution, we can infer the existence of the minimal large positive solution. Moreover, we also give some sufficient easily computable conditions for the existence of a large positive supersolution. Our results generalize, very substantially, some of the findings of García-Melián et al. (2016) adopting a rather novel methodology. 相似文献
44.
A. Račkauskas 《Acta Appl Math》1995,38(1):109-129
Let(X
i
) be a martingale difference sequence. LetY be a standard normal random variable. We investigate the rate of uniform convergence
相似文献
45.
A. Puhalskii 《Queueing Systems》1995,21(1-2):5-66
We establish the large deviation principle (LDP) for the virtual waiting time and queue length processes in the GI/GI/1 queue. The rate functions are found explicitly. As an application, we obtain the logarithmic asymptotics of the probabilities that the virtual waiting time and queue length exceed high levels at large times. Additional new results deal with the LDP for renewal processes and with the derivation of large8216.gif" alt="lsquo" align="BASELINE" BORDER="0">unconditionallarge8217.gif" alt="rsquo" align="BASELINE" BORDER="0"> LDPs for large8216.gif" alt="lsquo" align="BASELINE" BORDER="0">conditional oneslarge8217.gif" alt="rsquo" align="BASELINE" BORDER="0">. Our approach applies in large deviations ideas and methods of weak convergence theory.This work was supported in part by AT&T Bell Labs. 相似文献
46.
Vladimir Dobrić 《Journal of Theoretical Probability》1994,7(1):129-134
IfB is a weakly compactly generated Banach space andf: (S,S, large956.gif" alt="mgr" align="MIDDLE" BORDER="0">) satisfies the strong law of large numbers, thenf=f
1+f
2, wheref
1 is Bochner large956.gif" alt="mgr" align="MIDDLE" BORDER="0">-integrable andf
2 is Pettis large956.gif" alt="mgr" align="MIDDLE" BORDER="0">-integrable with Pettis norm 0. The decomposition is unique. 相似文献
47.
F. den Hollander 《Journal of statistical physics》1994,75(5-6):891-918
Some fifteen years ago, Shuler formulated three conjectures relating to the large-time asymptotic properties of a nearest-neighbor random walk on large8484.gif" alt="Zopf" align="BASELINE" BORDER="0">2 that is allowed to make horizontal steps everywhere but vertical steps only on a random fraction of the columns. We give a proof of his conjectures for the situation where the column distribution is stationary and satisfies a certain mixing codition. We also prove a strong form of scaling to anisotropic Brownian motion as well as a local limit theorem. The main ingredient of the proofs is a large-deviation estimate for the number of visits to a random set made by a simple random walk on large8484.gif" alt="Zopf" align="BASELINE" BORDER="0">. We briefly discuss extensions to higher dimension and to other types of random walk.Dedicated to Prof. K. E. Shuler on the occasion of his 70th birthday, celebrated at a Symposium in his honor on July 13, 1992, at the University of California at San Diego, La Jolla, California. 相似文献
48.
F. Cesi G. Guadagni F. Martinelli R. H. Schonmann 《Journal of statistical physics》1996,85(1-2):55-102
We consider the two-dimensional stochastic Ising model in finite square large923.gif" alt="Lambda" align="BASELINE" BORDER="0"> with free boundary conditions, at inverse temperature large946.gif" alt="beta" align="MIDDLE" BORDER="0">>large946.gif" alt="beta" align="MIDDLE" BORDER="0">0 and zero external field. Using duality and recent results of Ioffe on the Wulff construction close to the critical temperature, we extend some of the results obtained by Martinelli in the low-temperature regime to any temperature below the critical one. In particular we show that the gap in the spectrum of the generator of the dynamics goes to zero in the thermodynamic limit as an exponential of the side length of large923.gif" alt="Lambda" align="BASELINE" BORDER="0">, with a rate constant determined by the surface tension along one of the coordinate axes. We also extend to the same range of temperatures the result due to Shlosman on the equilibrium large deviations of the magnetization with free boundary conditions. 相似文献
49.
刘文 《应用数学学报(英文版)》1996,12(3):328-331
ASTRONGLIMITTHEOREMFORGENERALIZEDCANTOR-LIKE RANDOM SEQUENCESLIUWEN(刘文)(DepartmentofMathematicsandPhysics,HebeiUniversityofTe... 相似文献
50.
Nahid Emad 《Numerical Algorithms》1996,11(1):159-179
We make use of the Padé approximants and the Krylov sequencex, Ax,,...,A
m–1
x in the projection methods to compute a few Ritz values of a large hermitian matrixA of ordern. This process consists in approaching the poles ofR
x(large955.gif" alt="lambda" align="BASELINE" BORDER="0">)=((I–large955.gif" alt="lambda" align="BASELINE" BORDER="0">A)–1
x,x), the mean value of the resolvant ofA, by those of [m–1/m]Rx(large955.gif" alt="lambda" align="BASELINE" BORDER="0">), where [m–1/m]Rx(large955.gif" alt="lambda" align="BASELINE" BORDER="0">) is the Padé approximant of orderm of the functionR
x(large955.gif" alt="lambda" align="BASELINE" BORDER="0">). This is equivalent to approaching some eigenvalues ofA by the roots of the polynomial of degreem of the denominator of [m–1/m]Rx(large955.gif" alt="lambda" align="BASELINE" BORDER="0">). This projection method, called the Padé-Rayleigh-Ritz (PRR) method, provides a simple way to determine the minimum polynomial ofx in the Krylov subspace methods for the symmetrical case. The numerical stability of the PRR method can be ensured if the projection subspacem is large8220.gif" alt="ldquo" align="MIDDLE" BORDER="0">sufficientlylarge8221.gif" alt="rdquo" align="MIDDLE" BORDER="0"> small. The mainly expensive portion of this method is its projection phase, which is composed of the matrix-vector multiplications and, consequently, is well suited for parallel computing. This is also true when the matrices are sparse, as recently demonstrated, especially on massively parallel machines. This paper points out a relationship between the PRR and Lanczos methods and presents a theoretical comparison between them with regard to stability and parallelism. We then try to justify the use of this method under some assumptions. 相似文献
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