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81.
乔志军 《应用数学》1995,8(2):177-181
本文利用特征值的泛函梯度方法,先给出Tu谱问题的Lenard算子对;尔后通过求解一个关键性的算子方程,得到Tu谱问题的演化方程族之换位表示。  相似文献   
82.
Biot's consolidation theory is extended to a general class of viscoelastic bodies defined by Riemann-Stieltjes integral convolutions. From a new reciprocity theorem, proved for the governing equations including the inertia terms, the basic integral representations of the displacement fields and pore pressure are obtained. It is shown that, in the absence of internal inputs, a formulation of the dynamic problem in terms of the boundary unknown fields only is possible.  相似文献   
83.
We extend the Lévy inversion formula for the recovery of a bounded measure over R from its Fourier-Stieltjes transform to bounded complex-valued, orthogonally scattered Hilbert space-valued, and spectral projection operator-valued measures over any first countable locally compact Abelian group. All our results are direct generalizations of known inversions for R.  相似文献   
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85.
The theory developed in Ref. 1 is applied in a simplified form to a relativistic one-particle universe, and boundary symmetry conditions are imposed. The existence, for the particle, of a series of resonance states and a series of gauge states is derived. For the proton and the electron, a selection of such states accounts for the elementary particles observed to date.Dedicated to L. CesariThis research was sponsored by the United States Army under Contracts Nos. DAAG29-75-C-0024 and DAAG29-80-C-0041.This work was carried out at IMPA while the first author was visiting there in November 1981.  相似文献   
86.
The classical Ehresmann-Bruhat order describes the possible degenerations of a pair of flags in a linear space V under linear transformations of V; or equivalently, it describes the closure of an orbit of GL(V acting diagonally on the product of two flag varieties.We consider the degenerations of a triple consisting of two flags and a line, or equivalently the closure of an orbit of GL(V) acting diagonally on the product of two flag varieties and a projective space. We give a simple rank criterion to decide whether one triple can degenerate to another. We also classify the minimal degenerations, which involve not only reflections (i.e., transpositions) in the Weyl group SVSn = dim(V, but also cycles of arbitrary length. Our proofs use only elementary linear algebra and combinatorics.  相似文献   
87.
By using divided differences, we derive two different ways of representing the Lauricella function of n variables FD(n)(a,b1,b2,...,bn;c;x1,x2,...,xn) as a finite sum, for b1,b2,...,bn positive integers, and a,c both positive integers or both positive rational numbers with ca a positive integer. AMS subject classification 33D45, 40B05, 40C99Jieqing Tan: Research supported by the National Natural Science Foundation of China under Grant No. 10171026 and Anhui Provincial Natural Science Foundation under Grant No. 03046102.Ping Zhou: Corresponding author. Research supported by NSERC of Canada.  相似文献   
88.
The following is an expository paper, containing few and sometimes incomplete proofs, on continuous tensor products of Hilbert spaces and of group representations, and on the irreducibility of the latter; the principal results in the last direction are due to Verchik, Gelfand, and Graiev. The theory of continuous tensor products of Hilbert spaces, based on a fundamental theorem of Araki and Woods, is closely related to that of conditionally positive definite functions; it relies on the technique of symmetric Hilbert spaces, which also can be used to give a new proof of the classical Lévy-Khinchin formula (see A. Guichardet, (1973). J. Multiv.3 249–261.). Another basic tool for what follows is the 1-cohomology of unitary representations of locally compact groups; here, the main results are due to P. Delorme; let us mention, for instance, his results for the case of a group G containing a compact subgroup K such that L1(KβGK) is commutative, using a Lévy-Khinchin's type formula for K-invariant functions due to Gangolli, Faraut, and Harzallah. We add that the results exposed in that paper should have interesting connections with the central limit theorems à la Parthasarathy-Schmidt (see K. Parthasarathy, (1974). J. Multiv. Anal.4 123–149).  相似文献   
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90.
讨论了四对谱问题、相应的保谱方程族以及它们Lax表示的等价住,并利用这种等价关系可导出一些方程的Lax表示.  相似文献   
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