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991.
Evolutionary stability, the central solution concept in evolutionary game theory, is closely related to local asymptotic stability in a certain nonlinear dynamical system operating on the state space, the so-called "replicator dynamics". However, a purely dynamical characterization of evolutionary stability is not available in an elementary manner. This characterization can be achieved by investigating so-called "derived games" which consist of mixed strategies corresponding to successful states in the original game. Using well-known facts, several characterization results are obtained within this context. These also may shed light on the extremality properties of evolutionary stability. 相似文献
992.
基于粗糙集与层次分析法的组合预测方法 总被引:3,自引:0,他引:3
本文在改进的属性约简启发式算法 ,即应用加权平均的属性重要度对属性进行约简的基础上 ,将粗糙集理论和层次分析相结合 ,给出了一种全新的组合预测方法 . 相似文献
993.
Cantor尘的Hausdorff测度的初等证明 总被引:5,自引:1,他引:5
本文从自相似集的几何性质出发 ,用初等的方法得到了 Cantor尘的 Hausdorff测度 . 相似文献
994.
R. Henrion 《Journal of Optimization Theory and Applications》1992,72(1):187-197
The linear independence constraint qualification (LICQ) and the weaker Mangasarian-Fromovitz constraint qualification (MFCQ) are well-known concepts in nonlinear optimization. A theorem is proved suggesting that the set of feasible points for which MFCQ essentially differs from LICQ is small in a specified sense. As an auxiliary result, it is shown that, under MFCQ, the constraint set (even in semi-infinite optimization) is locally representable in epigraph form.The author wishes to thank Professor H. T. Jongen for valuable advice. 相似文献
995.
§ 1 IntroductionIn the last few years,invariant sets and attractors of (functional) differentialequations have been extensively discussed and various interesting results on the invariantsets and attractors,and estimates on the basin of attraction have been reported(see,forinstance,[1 ,2 ,4,6,1 0 ,1 3 ,1 5,1 8] ) .However,not much hasbeen developed in the directionof giving criteria on the existence of invariant sets and attractors for the functionaldifferential equations even though there ar… 相似文献
996.
区间值模糊集和区间值模糊推理 总被引:14,自引:3,他引:14
本文在单位区间的一切子区间集Ⅰ[0,1]上引入t-范、t-余范、交(∩)、并(∪)等概念,在此基础上定义了区间值模糊集中的新的交并运算和区间值模糊关系的新的合成运算,得出若干有趣的性质,并将其应用于区间值模糊推理的合成规则上。 相似文献
997.
We classify several classes of the subspaces of Banach spaces X for which there is a bounded linear operator from a Hilbert space onto a dense subset in X. Dually, we provide optimal affine homeomorphisms from weak star dual unit balls onto weakly compact sets in Hilbert spaces or in c0(Γ) spaces in their weak topology. The existence of such embeddings is characterized by the existence of certain uniformly Gâteaux smooth norms. 相似文献
998.
Ziba Eslami 《组合设计杂志》2003,11(5):312-316
In this article, we employ trades to construct an instance of an LS[7](3,5,11) which is the smallest unresolved LS[7](3,k,v) [ 9 ]. © 2003 Wiley Periodicals, Inc. J Combin Designs 11: 312–316, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jcd.10021 相似文献
999.
A. Barkhudaryan 《Applied Categorical Structures》2003,11(6):507-520
Functors uniquely determined by their object map are called DVO functors. In this paper, we continue the research into DVO endofunctors of the category Set of all sets and maps as started by V. Trnková, R. El Bashir and A. Barkhudaryan. Two families of connected DVO functors containing an isomorphic copy of the identity functor Id are described. 相似文献
1000.
Alon Noga; Bollobas Bela; Kim Jeong Han; Vu Van H. 《Proceedings London Mathematical Society》2003,86(2):273-301
A cover of a hypergraph is a collection of edges whose unioncontains all vertices. Let H = (V, E) be a k-uniform, D-regularhypergraph on n vertices, in which no two vertices are containedin more than o(D/e2k log D) edges as D tends to infinity. Ourresults include the fact that if k = o(log D), then there isa cover of (1 + o(1))n/k edges, extending the known result thatthis holds for fixed k. On the other hand, if k 4 log D thenthere are k-uniform, D-regular hypergraphs on n vertices inwhich no two vertices are contained in more than one edge, andyet the smallest cover has at least (nk) log (k log D)) edges.Several extensions and variants are also obtained, as well asthe following geometric application. The minimum number of linesrequired to separate n random points in the unit square is,almost surely, (n2/3 / (log n)1/3). 2000 Mathematical SubjectClassification: 05C65, 05D15, 60D05. 相似文献