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131.
拉单晶问题数学模型弱解的存在性和唯一性 总被引:2,自引:0,他引:2
朱宁 《高校应用数学学报(A辑)》1995,(3):235-244
本文考虑楔形区域G0T上的二相自由边界问题:其中a,b,b1,νp,h2为正常数。本文在适当的假设之下,证明了上述定解问题弱解的存在性和唯一性。 相似文献
132.
The concept of multitasking mathematical programs is discussed, and an application of multitasking to the multiple-cost-row linear programming problem is considered. Based on this, an algorithm for solving the Linear Complementarity Problem (LCP) in parallel is presented. A variety of computational results are presented using this multitasking approach on the CRAY X-MP/48. These results were obtained for randomly generated LCP's where thenxn dense matrixM has no special properties (hence, the problem is NP-hard). based on these results, an average time performance ofO(n
4) is observed. 相似文献
133.
Michael J. Todd 《Mathematical Programming》1982,24(1):216-224
We show that piecewise-linear homotopy algorithms may take a number of steps that grows exponentially with the dimension when solving a system of linear equations whose solution lies close to the starting point. Our examples are based on an example of Murty exhibiting exponential growth for Lemke's algorithm for the linear complementarity problem.This research was supported in part by NSF grant ECS-7921279 and by a Guggenheim Fellowship. 相似文献
134.
Jeremy F. Shapiro 《Mathematical Programming》1984,29(1):113-119
Node aggregation methods have been previously studied as a means for approximating large scale transportation problems. In
this paper, we show how the approximations inherent in Benders' decomposition method can be combined with node aggregation
in optimizing large scale capacitated plant location problems.
This research was supported by the National Science Foundation under Grant No. ECS-8117105. 相似文献
135.
David J. Unger 《Journal of Elasticity》2002,66(1):93-97
The two-dimensional point load problem on a linear elastic half plane is solved using a one-parameter group transformation of the biharmonic equation. This solution technique allows the incorporation of the singular load directly through use of the Dirac delta function. The resulting fourth-order ordinary differential equation, while formidable in appearance, is exact and is readily solved through simple integration. 相似文献
136.
Given a graph and a length function defined on its edge-set, the Traveling Salesman Problem can be described as the problem of finding a family of edges (an edge may be chosen several times) which forms a spanning Eulerian subgraph of minimum length. In this paper we characterize those graphs for which the convex hull of all solutions is given by the nonnegativity constraints and the classical cut constraints. This characterization is given in terms of excluded minors. A constructive characterization is also given which uses a small number of basic graphs. 相似文献
137.
The molecular conformation problem is discussed, and a concave quadratic global minimization approach for solving it is described. This approach is based on a quadratic assignment formulation of a discrete approximation to the original problem. 相似文献
138.
本文研究n阶非线性过值问题(NB)的奇异摄动。在较一般的条件下,应用高阶微分不等式理论证明了摄动解的存在性,并给出了摄动解直到n阶导函数的一致有效渐近展开式,推广和改进了已有的结果。 相似文献
139.
In this paper, the eigenvalue problem of a multilayer dielectric waveguide consisting of arbitrary number of layers is solved by the microwave network method. A general program with the function of computer graphics has been developed for analyzing the dispersion characteristics and the electromagnetic field distributions of an N layer dielectric waveguide. As examples of practical applications of the program, first, the dispersions and field patterns for the planar waveguides with refractive index of parabolic and exponential profiles are analyzed. Secondly, the procedure of mode conversion and mode separation in dielectric branching waveguides is vividly demonstrated through analyzing the field distributions of asymmetric multilayer dielectric structures and the general rules of mode conversion are discussed. The examples show that the present method possesses the advantages of versatility, rapidity, simplicity and accuracy. 相似文献
140.
Gianfranco d'Atri 《Mathematical Programming》1980,19(1):111-114
We introduce subclasses of the traveling salesman problem (TSP) and analyze the behaviour of heuristics on them. We derive bounds for the performance of the algorithms. 相似文献