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981.
Stéfane Fermigier 《Mathematische Annalen》1996,306(1):247-256
Sans résumé
Je remercie Jean-François Mestre, mon directeur de thèse, dont les idées sont à l'origine de ce travail, ainsi que Laurent Clozel, Guy Henniart et Jean-Pierre Labesse qui ont contribué par leur aide précieuse à son bon déroulement 相似文献
982.
Regular and well-posed formulation of the boundary integral method for a singular biharmonic problem
By adequate choice of a fundamental solution, the singular point of the solution is excluded from the integral equations. The use of a special differential operator yields a well-posed formulation of the system of two integral equations. Moreover, the application of the symmetry principle for biharmonic functions improves the efficiency of the method. Finally, the results are used to compute the coefficients of the William's series (stress intensity factors) which is the eigenfunction expansion of the solution around the singular point.The research was supported in part by the Technion VPR Fund-M. R. Saulson Research Fund. 相似文献
983.
Robert J. Finkelstein 《Letters in Mathematical Physics》1995,34(3):275-283
Although there is no empirical motivation for replacing the commutators of dynamically conjugate operators in quantum mechanics byq-commutators, it appears possible to construct a consistent mathematical formulism based on this idea. To examine such a possibility further, we have studied the relation of this proposal to the Schwinger action principle, since the entire quantum mechanical formulism may be inferred from this principle. In particular, we have discussed the quantum transformation theory within this framework.To Julian Schwinger, 1918–1994, one of the creators of quantum field theory, and a giant of twentieth-century physics 相似文献
984.
985.
We report an electron diffraction study of the molecular structure of gaseous cesium and thallium sulphates and cesium molybdate and tungstate. The average structure found for the M2XO4 molecules is described by a model (symmetry D2d) in which the metal atoms bridge two edges of an XO4 tetrahedron to form two 4-membered mutually perpendicular planar MO2X rings.The data lead to conclusions on the complex nature of intramolecular motion. This motion may roughly correspond to great displacements of metal atoms on the surface of an imaginary sphere described near the tetrahedral acid residue. 相似文献
986.
Our aim in this article is to study the existence and regularity of solutions of a quasilinear elliptic-hyperbolic equation. This equation appears in the design of blade cascade profiles. This leads to an inverse problem for designing two-dimensional channels with prescribed velocity distributions along channel walls. The governing equation is obtained by transformation of the physical domain to the plane defined by the streamlines and the potential lines of fluid. We establish an existence and regularity result of solutions for a more general framework which includes our physical problem as a specific example. 相似文献
987.
Let BG be the classifying space for stable spherical fibrations, and let V be a finite dimensional vector subspace of the cohomology algebra H1(BG; 2). We prove that V may be realized by a Poincaré duality space P, which means that if v:P→BG is the Spivak fibration, then v1 maps V isomorphically onto its image in H1(P;2). By construction, P is the product of a certain Grassman manifold and a spherical fiber space over a closed smooth manifold. 相似文献
988.
Every sufficiently large finite setX in [0,1) has a dilationnX mod 1 with small maximal gap and even small discrepancy. We establish a sharp quantitative version of this principle, which puts into a broader perspective some classical results on the distribution of power residues. The proof is based on a second-moment argument which reduces the problem to an estimate on the number of edges in a certain graph. Cycles in this graph correspond to solutions of a simple Diophantine equation: The growth asymptotics of these solutions, which can be determined from properties of lattices in Euclidean space, yield the required estimate.N.A.-Research supported in part by a U.S.A.-Israel BSF grant.Y.P.-Partially supported by a Weizmann Postdoctoral Fellowship. 相似文献
989.
José Felipe Voloch 《Monatshefte für Mathematik》1995,119(4):321-325
We study diophantine approximations to algebraic functions in characteristicp. We improve a theorem of Osgood, and give two classes of examples showing that this result is nearly sharp. One of these classes exhibits a new phenomenon. 相似文献
990.
R/S分析的理论基础:分数布朗运动 总被引:11,自引:0,他引:11
探讨了R/S分析方法的理论基础.指出稳定的Levy分布作为R/S分析的理论基础有重大缺陷。分析了分数布朗运动与R/S分析在含义和逻辑上的紧密联系,提出了分数布朗运动是R/S分析的理论基础的观点,最后,对我国上海股票市场进行了实证分析,其检验结果证实了本文提出的观点。 相似文献