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991.
Random walks on lattices. IV. Continuous-time walks and influence of absorbing boundaries 总被引:1,自引:0,他引:1
The general study of random walks on a lattice is developed further with emphasis on continuous-time walks with an asymmetric bias. Continuous time walks are characterized by random pauses between jumps, with a common pausing time distribution(t). An analytic solution in the form of an inverse Laplace transform for P(l, t), the probability of a walker being atl at timet if it started atl
o att=0, is obtained in the presence of completely absorbing boundaries. Numerical results for P(l, t) are presented for characteristically different (t), including one which leads to a non-Gaussian behavior for P(l, t) even for larget. Asymptotic results are obtained for the number of surviving walkers and the mean l showing the effect of the absorption at the boundary.This study was partially supported by ARPA and monitored by ONR(N00014-17-0308). 相似文献
992.
A. M. W. Verhagen 《Journal of statistical physics》1976,15(3):219-231
An anisotropic triangular Ising model in which the first- and second-order parameters and the field parameters are functionally related is solved exactly by representing the distribution of the atom patterns in terms of a suitably constructed Markov process. The probabilities of patterns, defined as the probabilities generated by this process, are a mathematically tractable alternative to the classical representation of these probabilities in terms of the partition function. The interaction and field parameters of this Ising model, its magnetization, free energy, and its nearest neighbor correlation functions, are expressed in terms of the parameters of this Markov process. Special cases are worked out in detail and numerical examples are given. 相似文献
993.
A survey of previous studies on vacuum deposited metal films shows that in high frequency measurements, explicit reference
to the effect of air-exposure is not made. The present work on bismuth films (in-situ and air-exposed) at dc and rf frequencies, carried out mainly to study the air-exposure effect, shows that in-situ
dc and rf and exposed rf all show nearly the same resistivity for thick continuous films. But air-exposed dc film resistances, when compared to in-situ
dc resistances, show that the grain boundary reflection coefficient, R
gin Mayadas-Shatzkes model changes from 0·2 to 0·6. This is shown to be due to the grain boundary oxidation. The result is
substantiated by rf measurements. 相似文献
994.
995.
E. Olusegun George Govind S. Mudholkar 《Annals of the Institute of Statistical Mathematics》1981,33(1):125-129
Summary A functional form of the characteristic function of the sample median of three variates is shown to characterize the logistic
distribution. A consequence of this is a characterization of the logistic in terms of the Laplace distribution.
Research sponsored in part by the Air Force Office of Scientific Research, Air Force Systems Command, USAF under Grant No.
AFOSR-77-3360. The United States Govenment is authorized to reproduce and distribute reprints for governmental purposes notwith-standing
any copyright notation hereon. 相似文献
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