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131.
广义拟变分不等式解集的稳定性及本质连通区的存在性 总被引:3,自引:3,他引:0
在赋范线性空间下.讨论广义拟变分不等式解集的稳定性,证明了满足一定连续性和凸性条件的广义拟变分不等式问题构成的空间M中,大多数(在Baire分类意义下)广义拟变分不等式问题的解集是稳定的,并证明了M中每一个广义拟变分不等式的解集至少存在一个本质连通区。 相似文献
132.
133.
该文研究了一个描述原细胞生长的反应扩散方程的自由边界问题.利用非线性分析中的线性化思想和偏微分方程的估计理论,证明了该自由边界问题局部古典解的存在唯一性. 相似文献
134.
We study elliptic systems of strongly nonlinear first-order differential equations in complex form on the plane. For such systems we develop the theory of Hilbert boundary value problems which is very much similar to the well-known theory for a holomorphic vector. Systems of nonlinear elliptic equations describe problems of interaction of several nonlinear stationary processes in the diffusive and convective mass and heat transport by hydrodynamic fluid flows. 相似文献
135.
We construct a model of a shell with piezoelectric elements (patches) that take into account the mutual influence of deformations and electric fields. Coupled problems for the shell with piezoelectric patches and an acoustic field, are studied and results on the existence and the uniqueness are obtained. For this system we consider an optimal control problem on noise attenuation and obtain results on the existence, the uniqueness, necessary and sufficient conditions of optimality. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
136.
The paper outlines a procedure to identify the space-and time-dependent external nonstationary load acting on a closed circular
cylindrical shell of medium thickness. Time-dependent deflections at several points of the shell are used as input data to
solve the inverse problem. Examples of numerical identification of various nonstationary loads, including moving ones are
presented. The relationship between the external load and the stress-strain state of the shell is described by the Volterra
equation of the first kind. The identification problem is solved using Tikhonov's regularization method and Apartsin's h-regularization method
__________
Translated from Prikladnaya Mekhanika, Vol. 44, No. 7, pp. 91–100, July 2008. 相似文献
137.
We investigate the six-dimensional Schrödinger equation for a three-body system with central pair interactions of a more general form than Coulomb interactions. Regular general and special physical solutions of this equation are represented by infinite asymptotic series in integer powers of the distance between two particles and in the sought functions of the other three-body coordinates. Constructing such functions in angular bases composed of spherical and bispherical harmonics or symmetrized Wigner D-functions is reduced to solving simple recursive algebraic equations. For projections of physical solutions on the angular bases functions, we derive boundary conditions at the pair impact point. 相似文献
138.
J. Haslinger T. Kozubek K. Kunisch G. Peichl 《Journal of Mathematical Analysis and Applications》2004,290(2):665-685
This contribution combines a shape optimization approach to free boundary value problems of Bernoulli type with an embedding domain technique. A theoretical framework is developed which allows to prove continuous dependence of the primal and dual variables in the resulting saddle point problems with respect to the domain. This ensures the existence of a solution of a related shape optimization problem in a sufficiently large class of admissible domains. 相似文献
139.
Grundel D. A. Oliveira C. A. S. Pardalos P. M. 《Journal of Optimization Theory and Applications》2004,122(3):487-500
The multidimensional assignment problem (MAP) is a NP-hard combinatorial optimization problem, occurring in many applications, such as data association. In this paper, we prove two conjectures made in Ref. 1 and based on data from computational experiments on MAPs. We show that the mean optimal objective function cost of random instances of the MAP goes to zero as the problem size increases, when assignment costs are independent exponentially or uniformly distributed random variables. We prove also that the mean optimal solution goes to negative infinity when assignment costs are independent normally distributed random variables. 相似文献
140.
A fourth‐order compact finite difference scheme on the nine‐point 2D stencil is formulated for solving the steady‐state Navier–Stokes/Boussinesq equations for two‐dimensional, incompressible fluid flow and heat transfer using the stream function–vorticity formulation. The main feature of the new fourth‐order compact scheme is that it allows point‐successive overrelaxation (SOR) or point‐successive underrelaxation iteration for all Rayleigh numbers Ra of physical interest and all Prandtl numbers Pr attempted. Numerical solutions are obtained for the model problem of natural convection in a square cavity with benchmark solutions and compared with some of the accurate results available in the literature. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献