摘要:

We study the collision operator of the Boltzmann equation for a semiconductor under the assumption of electron-phonon scattering processes. We assume the transition probability to be proportional to the distribution δ(ε (k′)−ε (k) ±hω), where ε(k) is the single-particle energy and ω the polar optical phonon frequency. We prove the existence of a numerable set of collision invariants and obtain an “H—theorem”. Moreover we analyze the initial value problem for spatially homogeneous distribution functions and we obtain an existence and uniqueness theorem. Our results can be applied to several situations and easily generalized.

ISSN:0041-1450    

DOI:10.1080/00411459108203906

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

In this paper, the time dependent linear transport equation with an isotropic, energy dependent, non-uniform bounded convex media and specular reflection boundary condition is considered. The existence, uniqueness and stability of its solution for initial value are proved. The spectral properties of the time independent linear transport operator are studied.

ISSN:0041-1450    

DOI:10.1080/00411459108203907

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Three different numerical algorithms for the solution of Cauchy type singular integral equations are compared by studying four test problems representing a variety of solutions expected. Numerical experiments show that Galerkin and collocation methods are comparable in accuracy either when the solution has no singularities at the end points or when these are present they are taken care by suitably chosen trial functions. Further, the dual quadrature collocation method introduced by Ioakimidis is seen to be equivalent to the conventional collocation scheme.

ISSN:0041-1450    

DOI:10.1080/00411459108203908

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

The Cabannesmodel with 14 velocities and 2 speeds is the simplest three-dimensional discrete Boltzmann model with a nontrivial temperature. We construct one family of one dimensional infinite-Mach-number shock wave solutions. We study the temperature and local entropy overshoots across the shock which represent two different physical effects. A general explanation of the local entropy overshoot is given.

ISSN:0041-1450    

DOI:10.1080/00411459108203909

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

The criticality factorchas been calculated for one—speed neutrons in spheres, infinite slabs and cylinders. The scattering is assumed to be a combination of linearly an isotropic scattering and strongly forward (Inönü) scattering. The earlier observed non—monotonic variation of the criticality factor with the degree of forward scattering has been shown to exist in this case, too, for slabs and cylinders. However, for such systems below a certain size the variation is monotonic. To facilitate these studies a simple criterion has been derived.

ISSN:0041-1450    

DOI:10.1080/00411459108203910

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor