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991.
We present some multifield variational principles for complex elastic solids characterized by any material microstructure. Some general constitutive arguments in the context of multifield hyperelasticity are also discussed. 相似文献
992.
In this paper, we derive an explicit group-invariant formula for the Euler–Lagrange equations associated with an invariant variational problem. The method relies on a group-invariant version of the variational bicomplex induced by a general equivariant moving frame construction, and is of independent interest. 相似文献
993.
J. B. Chilton 《Journal of Optimization Theory and Applications》1991,69(2):343-350
A sufficiency theorem is provided for the optimal control of systems with continuous leads wherein the motion of today's state is governed by the future trajectory of the control and the state. An application to the economics of dynamic limit pricing is given.This research had its origin in the doctoral dissertation of the author. The comments of H. Ryder are gratefully acknowledged. 相似文献
994.
n阶RFDE边值问题解的存在性和唯一性 总被引:2,自引:0,他引:2
利用不动点原理研究n阶RFDE边值问题解的存在性和唯一性,得到了一些新的结果. 相似文献
995.
W. Bian 《Journal of Optimization Theory and Applications》2006,129(2):277-292
Sufficient conditions are given for a mapping to be γ-G inverse differentiable. Constrained implicit function theorems for
γ-G inverse differentiable mappings are obtained, where the constraint is taken to be either a closed convex cone or a closed
subset. A theorem without assuming the γ-G inverse differentiability in a finite-dimensional space is also presented.
Communicated by F. A. Potra
The author thanks the referees for valuable suggestions concerning the presentation of this paper. He also thanks Professor
J. R. L. Webb and Dr. M. French for help. 相似文献
996.
Abdellah Bnouhachem Muhammad Aslam Noor 《Journal of Mathematical Analysis and Applications》2006,324(2):1195-1212
In this paper, we suggest and analyze a new inexact proximal point method for solving general variational inequalities, which can be considered as an implicit predictor-corrector method. An easily measurable error term is proposed with further relaxed error bound and an optimal step length is obtained by maximizing the profit-function and is dependent on the previous points. Our results include several known and new techniques for solving variational inequalities and related optimization problems. Results obtained in this paper can be viewed as an important improvement and refinement of the previously known results. Preliminary numerical experiments are included to illustrate the advantage and efficiency of the proposed method. 相似文献
997.
Christian G. Simader 《Mathematische Nachrichten》2006,279(4):415-430
For boundary data ? ∈ W 1,2(G ) (where G ? ?N is a bounded domain) it is an easy exercise to prove the existence of weak L 2‐solutions to the Dirichlet problem “Δu = 0 in G, u |?G = ? |?G ”. By means of Weyl's Lemma it is readily seen that there is ? ∈ C ∞(G ), Δ? = 0 and ? = u a.e. in G . On the contrary it seems to be a complicated task even for this simple equation to prove continuity of ? up to the boundary in a suitable domain if ? ∈ W 1,2(G ) ∩ C 0( ). The purpose of this paper is to present an elementary proof of that fact in (classical) Dirichlet domains. Here the method of weak solutions (resp. Dirichlet's principle) is equivalent to the classical approaches (Poincaré's “sweeping‐out method”, Perron's method). (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
998.
A transit equilibrium assignment problem assigns the passenger flows on to a congested transit (public transportation) network with asymmetric cost functions and a fixed origin-destination matrix. This problem which may be formulated in the space of hyperpath flows, is transformed into an equivalent problem in the space of total arc flows and an auxiliary variable. A simplicial decomposition algorithm is developed and its convergence is proved under the usual assumptions on the cost functions. The algorithm requires relatively little memory and its efficiency is demonstrated with computational results. 相似文献
999.
In this paper, the p-version hybrid/mixed finite element formulation using the Hu–Washizu principle is presented. The shape functions are assumed to be hierarchical for the displacement variables. The stresses and the strains are interpolated using Legendre polynomials so that the computation of the stiffness matrix will be simplified. For 2-D problems, the higher-order hierarchical shape functions start following the 8-node, quadrilateral shape functions. The geometry mapping of each element is also performed using an 8-node parametric mapping. Numerical examples for a plate with a circular hole and circular inclusion are included. 相似文献
1000.
Shen Yu-Liang 《Proceedings of the American Mathematical Society》1996,124(6):1879-1882
We will discuss the geometry of the unit sphere in the Banach space of integrable holomorphic quadratic differentials on a Riemann surface and answer some questions posed by L.R. Goldberg (Proc. Amer. Math. Soc. 118 (1993), 1179--1185).