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991.
本文研究了单位圆周上一类具有本质边界点的拟对称同胚,证明了它的极值拟共形延拓的最大伸缩商等于曲边四边形模之比的上确界. 相似文献
992.
Motivated by a simple optimal control problem with state constraints, we consider an inexact implementation of the primal-dual interior point algorithm of Zhang, Tapia, and Dennis. We show how the control problem can be formulated as a linear program in an infinite dimensional space in two different ways and prove convergence results.The research of this author was supported by an Overseas Research Scholarship of the Ministry of Education, Science and Culture of Japan.The research of this author was supported by National Science Foundation grants #DMS-9024622 and #DMS-9321938, North Atlantic Treaty Organization grant #CRG 920067, and an allocation of computing resources from the North Carolina Supercomputing Program.The research of this author was supported by North Atlantic Treaty Organization grant #CRG 920067. 相似文献
993.
Generalized quasiconvexities,cone saddle points,and minimax theorem for vector-valued functions 总被引:5,自引:0,他引:5
T. Tanaka 《Journal of Optimization Theory and Applications》1994,81(2):355-377
We establish the following theorems: (i) an existence theorem for weak type generalized saddle points; (ii) an existence theorem for strong type generalized saddle points; (iii) a generalized minimax theorem for a vector-valued function. These theorems are generalizations and extensions of the author's recent results. For such extensions, we propose new concepts of convexity and continuity of vector-valued functions, which are weaker than ordinary ones. Some of the proofs are based on a few key observations and also on the Browder coincidence theorem or the Tychonoff fixed-point theorem. Also, the minimax theorem follows from the existence theorem for weak type generalized saddle points. The main spaces with mathematical structures considered are real locally convex spaces and real ordered topological vector spaces.This paper is dedicated to Professor Kensuke Tanaka on his sixtieth birthday.This paper was written when the author was a visitor at the Department of Mathematical Science, Graduate School of Science and Technology, Niigata University, Niigata, Japan. The author is indebted to Prof. K. Tanaka for suggesting this work.The author is very grateful to Prof. P. L. Yu for his useful encouragement and suggestions and to the referees for their valuable suggestions and comments. 相似文献
994.
Structures of an asymmetrically coupled double-well superlattice by double-crystal X-ray diffraction
An asymmetrically coupled (GaAs/AlAs/GaAs/AlAs)/GaAs (001) double-well supperlattice is studied by HRDCD (high resolution
double-crystal X-ray diffractometry). The intensity of satellite peaks is modulated by wave packet of different sublayers.
In the course of simulation, the satellite peaks in the vicinity of the node points of wave packet are very informative for
precise determination of sublayer thickness and for improving accuracy. 相似文献
995.
This paper provides an analysis of the polynomiality of primal-dual interior point algorithms for nonlinear complementarity
problems using a wide neighborhood. A condition for the smoothness of the mapping is used, which is related to Zhu’s scaled
Lipschitz condition, but is also applicable to mappings that are not monotone. We show that a family of primal-dual affine
scaling algorithms generates an approximate solution (given a precision ε) of the nonlinear complementarity problem in a finite
number of iterations whose order is a polynomial ofn, ln(1/ε) and a condition number. If the mapping is linear then the results in this paper coincide with the ones in Jansen
et al., SIAM Journal on Optimization 7 (1997) 126–140.
Research supported in part by Grant-in-Aids for Encouragement of Young Scientists (06750066) from the Ministry of Education,
Science and Culture, Japan.
Research supported by Dutch Organization for Scientific Research (NWO), grant 611-304-028 相似文献
996.
关于区间上的Lorenz映射 总被引:1,自引:0,他引:1
本文引进了变换ζ.首先,用比文[4]简捷的方法证明了Lorenz映射的Sarkovski定理并更正了文[4]中的一个错误,还得到了扩张的Lorenz映射中周期点的存在性与其扩张常数之间的关系.其次,证明了Lorenz映射与其在变换ζ的像具有相等的捏制行列式.此外,给出了广义的Lorenz映射的周期点的存在性适合Sarkovski序关系的一个充分条件 相似文献
997.
Solving deterministic equivalent formulations of two-stage stochastic linear programs using interior point methods may be computationally difficult due to the need to factorize quite dense search direction matrices (e.g., AA
T
). Several methods for improving the algorithmic efficiency of interior point algorithms by reducing the density of these matrices have been proposed in the literature. Reformulating the program decreases the effort required to find a search direction, but at the expense of increased problem size. Using transpose product formulations (e.g., A
T
A) works well but is highly problem dependent. Schur complements may require solutions with potentially near singular matrices. Explicit factorizations of the search direction matrices eliminate these problems while only requiring the solution to several small, independent linear systems. These systems may be distributed across multiple processors. Computational experience with these methods suggests that substantial performance improvements are possible with each method and that, generally, explicit factorizations require the least computational effort. 相似文献
998.
Cyclic cellular automata are two-dimensional cellular automata which generalize lattice versions of the Lorentz gas and certain biochemistry models of artificial life. We show that rotators and time reversibility play a special role in the creation of closed orbits in cyclic cellular automata. We also prove that almost every orbit is closed (periodic) and the absence of diffusion for the flipping rotator model (also known as the ant). 相似文献
999.
光引力限制性三体问题的平动点 总被引:2,自引:1,他引:1
本文研究两个主星体的质量缩减因子q_,q_2∈(-∞,1]的光引力限制性三体问题。文中给出一种平动点的个数估计和位置计算的分析方法。结果表明对于不同的q_1和q_2可有1~7个平动点。作为应用,文末还讨论了太阳系类似彗尾尘埃物质的运动。 相似文献
1000.
Hsien-Chung Wu 《Fuzzy Optimization and Decision Making》2003,2(3):261-273
The fuzzy-valued Lagrangian function of fuzzy optimization problem via the concept of fuzzy scalar (inner) product is proposed. A solution concept of fuzzy optimization problem, which is essentially similar to the notion of Pareto solution in multiobjective optimization problems, is introduced by imposing a partial ordering on the set of all fuzzy numbers. Under these settings, the saddle point optimality conditions along with necessary and sufficient conditions for the absence of a duality gap are elicited. 相似文献