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1.
李雷  吴从 《数学学报》2001,44(6):1051-106
本文对于取值在Banach空间的几乎下半连续映射引入两个相关的下半连续闭凸集值映射,得到集值映射的连续选择存在性的若干特征,从而将 Deutsch E,和Kenderov P,De Blast F.S.和 Myjak J,Przeslawski K.和 Rybinski L E,Gutev V.等人以及作者自己的关于连续选择存在性的结果作为推论给出.并用这些结论讨论了在开映射定理不成立的。情况下从Banach空间到赋范空间上线性连续算子的齐性右逆存在问题.  相似文献   

2.
关于上半连续集值映象的连续选择问题   总被引:1,自引:0,他引:1  
向淑文 《数学学报》2000,43(2):329-336
本文进一步研究了上半连续集值映象的连续选择问题.首先,用一反例指出Aubin J、 P[1]中一结果不能成立.另外,对上半连续映象的σ-可选择性给出了另一逼近形式的结果.  相似文献   

3.
Using Bressan-Colombo results, concerning the existence of continuous selections of lower semicontinuous multifunctions with decomposable values, we prove a continuous version of Filippov’s theorem for a fractional differential inclusion.  相似文献   

4.
In the present article many theorems about existence of continuous selections for a set-valued mapping into the metrizable spaces are extended to mappings into non-metrizable spaces.  相似文献   

5.
Using Bressan-Colombo results,concerning the existence of continuous selections of lower semicontinuous multifunctions with decomposable values,we prove a continuous version of Filippov’s theorem for a fractional integro-differential inclusion involving Caputo’s fractional derivative.This result allows us to obtain a continuous selection of the solution set of the problem considered.  相似文献   

6.
We discuss several concepts of continuity, weaker than lower semicontinuity, but still implying the existence of a continuous selection for a closed convex valued multifunction from a paracompact Hausdorff topological space into a Banach space. In this way, an extension of Michael's celebrated selection theorem is given. The behavior of -envelop approximations, as well as the localization of continuous selections, is also discussed.  相似文献   

7.
In this paper, a new notion of exceptional family of elements (EFE) for a pair of functions involved in the implicit complementarity problem (ICP) is introduced. Based upon this notion and the Leray–Schauder Alternative, a general alternative is obtained which gives more general existence theorems for the implicit complementarity problem. Finally, via the techniques of continuous selections, these existence theorems are extended to the multi-valued implicit complementarity problems (MIPS).  相似文献   

8.
Problems in set-valued optimization can be solved via set optimization. In this paper optimality conditions are studied for set-valued maps with set optimization. Optimality requirements are established for continuous selections using directional derivatives. Necessary and sufficient conditions for the existence of solutions are shown for set-valued maps under generalized convexity assumptions and with the notion of the contingent derivative.  相似文献   

9.
带随机过程的随机规划问题最优解集的过程特性与稳定性   总被引:1,自引:0,他引:1  
本文证明了带随机过程的随机规划问题最优解集做为集值随机过程的可测性、可测最优解选择过程的存在性。研究了最优解集过程的平稳性、马氏性以及最优值过程的鞅性和最优解集过程的集值鞅性。最后,讨论了在有限维分布意义下最优解集过程对所含随机过程参数的连续性以及最优值过程的稳定性。  相似文献   

10.
We examine the existence of continuous selections for the parametric projection onto weak Chebyshev subspaces. In particular, we show that if is the class of polynomial splines of degree n with the k fixed knots then the parametric projection admits a continuous selection if and only if the number of knots does not exceed the degree of splines plus one. February 15, 1996. Date revised: September 16, 1996.  相似文献   

11.
《Optimization》2012,61(5):535-554
Continuous selections of linear functions play an important role in Morse theory for piecewise C 2-functions. In this article, the topological properties of continuous selections of linear functions are investigated in detail. These are then utilized to provide a complete classification of all continuous selections of five linear functions. This is done by showing that the first four Betti numbers of a simplicial complex induced by such a function fully determine that function up to topological equivalence. The number of different topological types of continuous selections of linear functions has been known only in the case of four or less selection functions so far. The main result of this article now states that there are exactly 26 different topological types of continuous selections of five linear functions.  相似文献   

12.
We prove an existence result of approximate selections for multi-valued maps defined on finite dimensional metric spaces. We impose to our applications to be upper semi continuous and to have a values having contractible small neighborhoods. To cite this article: Y. Askoura, C. R. Acad. Sci. Paris, Ser. I 339 (2004).  相似文献   

13.
Using Bressan–Colombo results concerning the existence of continuous selections of lower semicontinuous multifunctions with decomposable values, we prove that the set of derivatives of solutions of a class of nonlinear integrodifferential inclusions is retract of L1 loc([0, ∞), Rn). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

14.
The present paper improves a result of Gutev [V. Gutev, Approaching points by continuous selections, J. Math. Soc. Japan (4) (2006) 1203–1210] by characterizing the countably-approachable points in sense of [V. Gutev, Approaching points by continuous selections, J. Math. Soc. Japan (4) (2006) 1203–1210] by a natural extreme-like condition in the spirit of [V. Gutev, T. Nogura, Vietoris continuous selections and disconnectedness-like properties, Proc. Amer. Math. Soc. 129 (2001) 2809–2815; V. Gutev, T. Nogura, Selection pointwise-maximal spaces, Topology Appl. 146–147 (2005) 397–408]. This demonstrates the natural relationship between different extreme-like points with respect to continuous selections for the Vietoris hyperspace of nonempty closed subsets.  相似文献   

15.
Given a strictly positive measure, we characterize inner semicontinuous solid convex-valued mappings for which continuous functions which are selections almost everywhere are selections. This class contains continuous mappings as well as fully lower semicontinuous closed convex-valued mappings that arise in variational analysis and optimization of integral functionals. The characterization allows for extending existing results on convex conjugates of integral functionals on continuous functions. We also give an application to integral functionals on left continuous functions of bounded variation.  相似文献   

16.
It is shown that the construction of needle variations can be carried out for almost lower semicontinuous differential inclusions rather than for the case of ordinary single-valued continuously differentiable vector fields usually considered in the literature. The construction leads to needle variations whose flows are in general set-valued but still have good differentiability properties. The variations are constructed by using single-valued selections that are not necessarily continuous with respect to the state variable, but have instead a much weaker 'integral continuity' property, somewhat more general that the 'directional continuity' considered in previous work by A. Cambini and S. Querci, A. Pucci, and A. Bressan. The existence of many such selections is proved by slightly adapting an argument due to Bressan, extending it from the lower semicontinuous to the almost lower semicontinuous case, and strengthening it to yield not only directional continuity at all points but also full continuity at a specified point.  相似文献   

17.
In a series of papers the last two authors have obtained a complete characterization of those finite-dimensional subspaces G of C[a,b] for which there exists a continuous selection for the metric projection onto G. By showing that all continuous selections constructed there are even pointwise-Lipschitz-continuous and quasi-linear, we get a complete characterization concerning selections for the metric projection with this stronger property.  相似文献   

18.
给出了-些从仿紧拓扑空间到FC-空间的新的连续选择;也给出了-些从仿紧拓扑空间到局部FC-一致空间的新的邻近选择.这些结果改进且推广了-些近来的结论.  相似文献   

19.
The paper deals with affine selections of affine (both convex and concave) multifunctions acting between finite-dimensional real normed spaces. It is proved that each affine multifunction with compact values possesses an exhaustive family of affine selections and, consequently, can be represented by its affine selections. Moreover, a convex multifunction with compact values possesses an exhaustive family of affine selections if and only if it is affine. Thus the existence of an exhaustive family of affine selections is the characteristic feature of affine multifunctions which differs them from other convex multifunctions with compact values. Besides a necessary and sufficient condition for a concave multifunction to be affine on a given convex subset is also proved. Finally it is shown that each affine multifunction with compact values can be represented as the closed convex hull of its exposed affine selections and as the convex hull of its extreme affine selections. These statements extend the Straszewicz theorem and the Krein–Milman theorem to affine multifunctions. Dedicated to Boris Mordukhovich in honour of his 60th birthday.  相似文献   

20.
For certain classes of locally Lipschitzian functions (continuous selections, componentwise maximum functions of Cfc-mappings) we compute bounds on the entropy dimension of the set of generalized, critical values. This yields a measure of metric complexity to compare these classes. For vector valued functions we also compare different concepts of derivatives from this metric point of view. For continuous selections of differentiable functions even explicit bounds on the e-entropy of the nearly critical values of f are provided.  相似文献   

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