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71.
Summary  The following mixed boundary-value problem for a transversely isotropic elastic half-space is considered. Arbitrary tangential displacements are prescribed at the exterior of a circle, while the interior of the circle is free of tangential stress, and the normal stress vanishes all over the boundary. The governing integral equation is solved exactly, in closed form, and in terms of elementary functions. The method of continuation of solutions previously published by the author has been used here. Several examples are considered. No similar results has been reported before, even in the case of an isotropic body. Received 8 May 2000; accepted for publication 20 July 2000  相似文献   
72.
In this article,the authors obtain an integral representation for the relaxation of the functional
F(x,u,Ω):={∫^f(x,u(x),εu(x))dx Ω if u∈W^1,1(Ω,R^N), +∞ otherwise, in the space of functions of bounded deformation,with respect to L^1-convergence.Here Eu represents the absolutely continuous part of the symmetrized distributional derivative Eu.f(x,p,ξ)satisfying weak convexity assumption.  相似文献   
73.
We compute the Casson invariant for some integral homology 3-spheres. We also show that for every integer n, there exists an integral homology 3-sphere of Mazur type with the Casson invariant 2n.  相似文献   
74.
Modification of a peptide-αthioester with a sequence of six arginines on the thioester leaving group can render soluble all peptides derived from a polytopic integral membrane protein. This strategy greatly simplifies the synthesis of peptide-αthioester building blocks for the total chemical synthesis of integral membrane proteins by native chemical ligation.  相似文献   
75.
This paper is concerned with the solvability and waveform relaxation methods of linear variable-coefficient differential-algebraic equations (DAEs). Most of the previous works have been focused on linear variable-coefficient DAEs with smooth coefficients and data, yet no results related to the convergence rate of the corresponding waveform relaxation methods has been obtained. In this paper, we develope the solvability theory for the linear variable-coefficient DAEs on Legesgue square-integrable function space in both traditional and least squares senses, and determine the convergence rate of the waveform relaxation methods for solving linear variable-coefficient DAEs.  相似文献   
76.
77.
In this paper, a class of impulsive Caputo fractional functional differential systems with variable impulsive perturbations is investigated. Sufficient conditions for the existence of integral manifolds are obtained. The main results are proved by means of piecewise continuous Lyapunov functions and the fractional comparison principle. The demonstrated techniques can be applied in studying properties of many applied problems of diverse interest.  相似文献   
78.
设Fq是q元有限域,这里q是任意一个素数p的方幂。本文利用Fq上奇异辛几何给出当A,B分别是阶n秩2v和m秩2s的一般交错矩阵时,Fq上适合方程XAX‘=B的秩k的解X和解X的个数的明显公式,并用q超几何级数简化表达公式。  相似文献   
79.
The uniqueness theorem for generalized solutions of initial-boundary problems for the Marguerre—Vlasov vibrations of shallow shells with clamped boundary conditions is proved. A unique method developed by the author, based upon a nonstandard treatment of smoothing operators, is applied instead of using an enclosure theorem at the critical values of indices. Accepted 10 November 1997  相似文献   
80.
An integral approach for large deflection cantilever beams   总被引:1,自引:0,他引:1  
A new integral approach is proposed to solve the large deflection cantilever beam problems. By using the moment integral treatment, this approach can be applied to problems of complex load and varying beam properties. This versatile approach generally requires only simple numerical techniques thus is easy for application. Treatment for typical loading and beam property conditions are presented to demonstrate the capability of this approach.  相似文献   
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