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61.
具有可变到达率的多重休假Geo~(λ_1,λ_2)/G/1排队分析 总被引:1,自引:0,他引:1
本文考虑顾客到达与服务员休假相关的多重休假离散时间排队系统,用更新过程及u-变换分析了系统的队长性质.分别得到系统在三种时点(n~-,n~+,n)处的队长分布的递推解,进而揭示了在不同到达率条件下系统队长分布不再具有随机分解特性,得到了系统在四种时点(n~-,n~+,n,离去时点D_n)处稳态队长分布的重要关系(不同于连续时间排队系统). 相似文献
62.
A lattice random walk model based on particles scattering on discrete lattice of homogenous space is introduced. The discrete Green's function (DFG) for two-dimensional and three-dimensional lattice random walk of photon is found and proved by mathematical induction. The convolution theorem of photon lattice random walk is presented. They can be used with the method of images to calculate the photon density distribution in semi-infinite and finite slab homogenous turbid media such as tissue. 相似文献
63.
REN Hongwu FANG Zhujie 《Chinese Journal of Lasers》1999,8(6):525-530
1 Introduction Opticaltomographyprovidesanalternativetechnologytoprobebreastcancerandmonitorhumantissue’sfunctionalparameternoninvasively[1,2].Photonmigrationintissueplaysakeyroleinopticaltomography.Recently,alatticerandomwalkmodel[3,4]isemployedtod… 相似文献
64.
Milton Rosenberg 《Journal of multivariate analysis》1978,8(2):295-316
Let p, q be arbitrary parameter sets, and let be a Hilbert space. We say that x = (xi)i?q, xi ? , is a bounded operator-forming vector (?Fq) if the Gram matrix 〈x, x〉 = [(xi, xj)]i?q,j?q is the matrix of a bounded (necessarily ≥ 0) operator on , the Hilbert space of square-summable complex-valued functions on q. Let A be p × q, i.e., let A be a linear operator from to . Then exists a linear operator ǎ from (the Banach space) Fq to Fp on (A) = {x:x ? Fq, is p × q bounded on } such that y = ǎx satisfies yj?σ(x) = {space spanned by the xi}, 〈y, x〉 = A〈x, x〉 and . This is a generalization of our earlier [J. Multivariate Anal.4 (1974), 166–209; 6 (1976), 538–571] results for the case of a spectral measure concentrated on one point. We apply these tools to investigate q-variate wide-sense Markov processes. 相似文献
65.
A. López-Ortega 《General Relativity and Gravitation》2006,38(5):743-771
We extensively study the exact solutions of the massless Dirac equation in 3D de Sitter spacetime that we published recently. Using the Newman-Penrose formalism, we find exact solutions of the equations of motion for the massless classical fields of spin s= 12,1,2 and to the massive Dirac equation in 4D de Sitter metric. Employing these solutions, we analyze the absorption by the cosmological horizon and de Sitter quasinormal modes. We also comment on the results given by other authors. 相似文献
66.
F. F. Gong F. X. Gong F. Y. Gong 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,49(3):267-268
Open dynamic behaviour of financial markets with internal
interactions between agents and with external “fields” from other systems
are investigated using the approach of Grossman and Stiglitz for inefficient
markets, and Keynes for interference of the market using physics of finance
(referred to hereafter as phynance). The simulation results indicate that
the NYSE data analyzed in Plerou, V. et al., Nature 421, 130 (2003) can be fitted
by an equation of order parameter Φ and local deviation R of type:
-(R+0.03) Φ+ 0.6 Φ3 + 0.02 = 0, which is shown to be in
remarkable agreement with Plerou's data. 相似文献
67.
68.
Based on the neutron induced fission fragment mass distribution data up to neutron energy 20 MeV measured with the double kinetic energy method (KEM) and the radio active method (RAM), the systematics of fission fragment mass distribution was investigated by using 5 Gaussian model and the systematics parameters were obtained by fitting the experimental data. With the systematics, the yields of any mass A and at any energy in the region from 0 to 20 MeV of neutron energy can be calculated. The calculated results could well reproduce the experimental data measured with KEM, but show some systematical deviation from the data measured by RAM, which reflects some systematical deviations between the two kinds of measured data.The error of systematics yield was calculated in an exact error transformation way, including from the error of the experimental yield data to the error of the discrete parameters, then to the systematics parameters,and at last to the yield calculated with systematics. 相似文献
69.
Synchronization of stochastically hybrid coupled neural networks with coupling discrete and distributed time-varying delays 下载免费PDF全文
A general model of linearly stochastically coupled identical connected neural networks with hybrid coupling is proposed, which is composed of constant coupling, coupling discrete time-varying delay and coupling distributed timevarying delay. All the coupling terms are subjected to stochastic disturbances described in terms of Brownian motion, which reflects a more realistic dynamical behaviour of coupled systems in practice. Based on a simple adaptive feedback controller and stochastic stability theory, several sufficient criteria are presented to ensure the synchronization of linearly stochastically coupled complex networks with coupling mixed time-varying delays. Finally, numerical simulations illustrated by scale-free complex networks verify the effectiveness of the proposed controllers. 相似文献
70.