摘要:

Group theoretical considerations originating from Wigner are applied to the few group diffusion equation (DE) and to the linear Boltzmann transport equation (TE). The irreducible subspaces invariant under the symmetries of the TE or DE determine specific incoming current patterns. If these patterns are used in the response matrix formulation, the response matrix will be diagonal. A method for obtaining a solution that belongs to a given irreducible subspace is provided. These considerations are utilized in a coarse-mesh program. It is shown that the solution to a boundary condition problem is determined by the irreducible decomposition of the boundary condition and by the solutions belonging to the irreducible boundary conditions. Finally, the solution of the TE in an infinite lattice is investigated and the results are utilized to solve the TE in a finite lattice.

ISSN:0041-1450    

DOI:10.1080/00411458608210452

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

For alinear transport equation it is shown that in the limit of small mean free path, Maxwellian reflexion laws with accommodation coefficient behave as total absorbers of the impulse components tangential to a wall. Without using any regularity properties of the solutions, it is proven that the no-slip condition holds in the diffusion limit.

ISSN:0041-1450    

DOI:10.1080/00411458608210453

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Stability of solutions of abstract half-space problems of the type T ψ'1(x)=-Aψ(x)(0> x > ∞) is established under perturbations of the resolvent of the (unbounded) positive self-adjoint operator A. Applications are given to Sturm-Liouville type diffusion equations.

ISSN:0041-1450    

DOI:10.1080/00411458608210454

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Of central importance in understanding the behavior of fluids is their developnent in time, beginning with initial conditions far from equilibrium. Here, I extend a recent result of Illner and me [5] regarding such flows in all of IR3to flows of the same type over a body. Except for solutions near equilibriun [10, 11], this is the first result I know of this type associated with the Boltzmann equation.

ISSN:0041-1450    

DOI:10.1080/00411458608210455

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The equation of transfer for a homogeneous, linearly anisotropic sphere with internal sources and a specular and diffuse surface is reduced to an integral equation. Homogeneous boundary conditions are directly incorporated in the kernels of the integral equation.

ISSN:0041-1450    

DOI:10.1080/00411458608210456

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

With about 4% of the periodicity and nearly the regularity, of Edmond Halley's celestial namesake, kinetic theorists gather in the Black Forest for a weeklong conference. At least so it has been since 1976, when the first of these meetings was convened under the leadership of Helmut Neunzert and Donald Pack. Each of these meetings has been duly reported on in this Journal, and herewith we continue the practice. (For the 1976 meeting, entitled “Mathematical Methods in Transport Theory,” see [I]; for the 1979 and 1982 meetings, entitled as the present one, see [2, 31.) The present meeting convened in the first week of May, and with the expert guidance of our leaders, as well as tolerable weather, met our high expectations of delightful and informative sessions. Research areas covered extensively included Vlasov theory and linear and nonlinear Boltzmann theory, with a few contributions more nearly described as general numerical methods and applicable operator theory. We describe first the Vlasov results.

ISSN:0041-1450    

DOI:10.1080/00411458608210457

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Approximately forty mathematicians and physicists gathered for this informal workshop in Paris. The workshop was organized by the Institute for Applied Mathematics of the École Normale Supérleure under the supervision of Professor C. Bardos.

ISSN:0041-1450    

DOI:10.1080/00411458608210458

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A Workshop on Operator Theory and its Applications was held at, the Vrije Universiteit in Amsterdam Junc 4–7, 1985, organized by H. Bart (Erasmus University, Rotterdam), I. Gohberg (Tel-Aviv University, Tel-Aviv) and M. A. Kaashoek (Vrije Universiteit). Besides institutional sponsors (Vrije Iniversiteit, Erasmus Universiteit, Koninklijke Nederlandse Akademie van Wetenschappen and Vertrouwenscommissie), corporate sponsors (Control Data B. V., Philips International B.V. and I.B.M. Nederland N.V.) provided financial support; this hclped make arrangements quite comfortable for the participants - but with one unfortunate exception. Bruce Francis suffered an accident and had to spend the period of the conference in the hospital, but now is recovering. There were 30 lectures presented. There was some attempt t o cluster lectures of similar themes; in certain instances this was very effective.

ISSN:0041-1450    

DOI:10.1080/00411458608210459

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

As most readers of this journal know very well, a bi-annual series of transport theory conferences has been held since 1969. The '69, '73, '75, '77 and '83 meetings were organized and held in Blacksburg, Virginia on the campus of Virginia Tech, and although the conference has moved to various other locations (Los Alamos in 1971; Tucson, Arizona in 1979; Lubbock, TX in 1981 and, of course, Montecatini, Italy this year) the meetings still have their roots in Blacksburg and, in fact, the 1989 meeting will return there after still another detour—to UCLA—in 1987.

ISSN:0041-1450    

DOI:10.1080/00411458608210460

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

This conference was organized under the aegis of the University of Joensuu “to review the impact of the E.P.R. argument on the development of quantum theory, to discuss the philosophical implications of recent experimental and theoretical results on the E.P.R. problem, and to survey some other recent trends in the interpretation of quantum mechanics and classical mechanics.” There were approximately fifty lectures (and another fifty offered), two panel discussions, with over one hundred and fifty participants representing twenty five countries, which is remarkable since one physicist reviewing the original proposal for the conference termed E.P.R. as “the problem that is not a problem!”

ISSN:0041-1450    

DOI:10.1080/00411458608210461

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor