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991.
X. Y. Zheng X. M. Yang K. L. Teo 《Journal of Optimization Theory and Applications》2007,133(2):275-288
We study efficient point sets in terms of extreme points, positive support points and strongly positive exposed points. In
the case when the ordering cone has a bounded base, we prove that the efficient point set of a weakly compact convex set is
contained in the closed convex hull of its strongly positive exposed points, thereby extending the Phelps theorem. We study
also the density of positive proper efficient point sets.
This research was supported by a Central Research Grant of Hong Kong Polytechnic University, Grant G-T 507. Research of the
first author was also supported by the National Natural Science Foundation of P.R. China, Grant 10361008, and the Natural
Science Foundation of Yunnan Province, China, Grant 2003A002M. Research of the second author was also supported by the Natural
Science Foundation of Chongqing. Research of the third author was supported by a research grant from Australian Research Counsil. 相似文献
992.
复杂通信网络的结构分解法及其在可靠性分析中的应用 总被引:2,自引:0,他引:2
对复杂通信网络拓扑结构的恰当描述与刻画是研究其可靠性及确定信号流在其中有效的传输方式的前提。通过引进适当的数据结构并采用递归分解的技巧,本给出了将任意复杂通信网络分解为环、弦、链等基本网络结构的某种组合与连接的结构分解法,并由此得到了研究网络可靠性的新的两阶段法,即先分析各基本结构的可靠性,再由此给出原网络可靠性的估计。 相似文献
993.
We give some structure to the Brown–Peterson cohomology (or its p-completion) of a wide class of spaces. The class of spaces are those with Morava K-theory even-dimensional. We can say that the Brown–Peterson cohomology is even-dimensional (concentrated in even degrees) and is flat as a BP*-module for the category of finitely presented BP*(BP)-modules. At first glance this would seem to be a very restricted class of spaces but the world abounds with naturally occurring examples: Eilenberg-Mac Lane spaces, loops of finite Postnikov systems, classifying spaces of most finite groups whose Morava K-theory is known (including the symmetric groups), QS2n, BO(n), MO(n), BO, Im J, etc. We finish with an explicit algebraic construction of the Brown–Peterson cohomology of a product of Eilenberg–Mac Lane spaces and a general Künneth isomorphism applicable to our situation. 相似文献
994.
L. Kuntz 《Journal of Optimization Theory and Applications》1995,86(1):263-270
A new implicit function theorem for a class of nonsmooth functions is proved. It is used to improve the directional implicit function theorem of Demidova and Demyanov (Ref. 1). 相似文献
995.
996.
Jean B. Lasserre 《Proceedings of the American Mathematical Society》1998,126(1):189-194
We consider a linear sytem in a Banach lattice and provide a simple theorem of the alternative (or Farkas lemma) without the usual closure condition.
997.
998.
Pietro Aiena Maria Luisa Colasante Manuel Gonzá lez 《Proceedings of the American Mathematical Society》2002,130(9):2701-2710
We find several conditions for the quasi-nilpotent part of a bounded operator acting on a Banach space to be closed. Most of these conditions are established for semi-Fredholm operators or, more generally, for operators which admit a generalized Kato decomposition. For these operators the property of having a closed quasi-nilpotent part is related to the so-called single valued extension property.
999.
GAN DANYAN 《数学年刊B辑(英文版)》1994,15(1):123-127
ON THE SHEAF OF GENERALIZED FUNDAMENTAL GROUP AND COVERING SPACE¥GANDANYANAbstract:Theauthorconstructsthesheafofgeneralizedfu... 相似文献
1000.