多值1—集—压缩不动点的注记

设X是一Banach空间,CK(X)表X的一切非空凸子集的族。P表X内一锥和α表X上的Kuratowski非紧性测度。有关概念、术语和记号,可参见[2,3]。利用[3]内多值凝聚映象的不动点指数理论和类似于[3]的定理3.2证明中的论证方法,     

非紧域上集值映象的重合点与不动点

在赋范线性空间的非空非紧凸集上建立了集值映象对的一个重合点定理,然后用这一定理改进了文献［１］中的集值映象内向集定理与外向集定理,并得到几个集值映象不动点定理．     

集值映象重合点定理的进一步改进和推广

本文是文［１］的继续．在更一般的条件下，研究了完备度量空间中集值映象的重合点和不动点存在性问题     

1—集压缩映射的主零不动点

本文给出了１－集压缩映射的一些新的非零不动定理，它们推广和改进了［１，２，４，５］中的某些重要定理。     

集值映象的不动点定理

本文讨论了定义在仿紧凸集上的集值映象的有关性质,并由此得到了集值映象的平衡点和不动点存在性的若干充分条件,推广了一些已有的结果.     

非扩张映象的重合点与不动点

本文在凸度量空间中讨论了集什扩张映象对的重合和非扩张映象列的公共不动点的存在性，所得结论是单值非扩张映象数情形的推广和发展。．     

半紧1—集压缩映射的不动点定理及固有值...

本文给出了与Ｌｅｒａｙ－Ｓｃｈａｕｄｅｒ边界条件紧密相关的其它五种形式：弱ＬＳ、弹ＢＰ、ＬＳＢ、弱ＣＲ和弱向内条件，并阐述这些条件之间关系。在此基础上，我们得到 了半紧１－集压缩映射的不动点定理及固有值。     

PM-空间中混合压缩的不动点定理与重合点定理

引进了Menger PM-空间中多值情形下的相容映象和弱相容映象概念，并研究了二者之间的联系．在此基础上，获得了Menger PM-空间中若干新的不动点和重合点定理．最后，给出了这一结果在度量空间中的应用．     

H—空间中集值映象的不动点定理

本文在Ｈ－空间的框架下，不依赖于ＫＭＭ技巧，建立了新的集值映象不动点定理，并且这一结果以赋范空间中的Ｆａｎ－Ｇｌｉｃｋｓｂｅｒｇ－Ｋａｋｕｔａｎｉ定理为特例，从而将这一重要定理推至Ｈ－空间。     

生存轨道与集值映象的不动点

基于无穷维空间中的生存定理，我们研究了集值映象的不动点，得到了一个新的不动点定理，推广和改进了[1]和[5]中的相应结果。     

1－集压缩映射的非零不动点

本文给出了１－集压缩映射的一些新的非零不动点定理，它推广和改进了［１，２，４，５］中的某些重要定理．     

Fixed Points for Mean Non-expansive Mappings

For a Banach Space X Garcia-Falset introduced the coefficient R（X） and showed that if R（X） 〈 2 then X has a fixed point. In this paper, we define a mean non-expansive mapping T on X in the sense that ｜｜Tx - TY｜｜ ≤ a｜｜x - y｜｜ ＋ b｜｜x - Ty｜｜ for any x,y E X, where a,b ≥ 0, a ＋ b ≤ 1. We show that if R（X） 〈 1/1＋b then T has a fixed point in X.     

Generic Existence of Fixed Points for Set-Valued Mappings

We first consider a complete metric space of nonexpansive set-valued mappings acting on a closed convex subset of a Banach space with a nonempty interior, and show that a generic mapping in this space has a fixed point. We then establish analogous results for two complete metric spaces of set-valued mappings with convex graphs.     

Approximating Fixed Points of Weakly Contracting Mappings

We consider the problem of approximating fixed points of contractive functions whose contraction factor is close to 1. In a previous paper (1993, K. Sikorski et al., J. Complexity9, 181–200), we proved that for the absolute error criterion, the upper bound on the number of function evaluations to compute ε-approximations is O(n³(ln(1/ε)+ln(1/(1−q))+ln n)) in the worst case, where 0<q<1 is the contraction factor in the Euclidean norm and n is the dimension of the problem. This upper bound is achieved by the circumscribed ellipsoid (CE) algorithm combined with a dimensional deflation process. In this paper we present an inscribed ellipsoid (IE) algorithm that enjoys O(n(ln(1/ε)+ln(1/(1−q)))) bound. For q close to 1, the IE algorithm thus runs in many fewer iterations than the simple iteration method, that requires ⌈ln(1/ε)/ln(1/q)⌉ function evaluations. Our analysis also implies that: (1) The dimensional deflation procedure in the CE algorithm is not necessary and that the resulting “plain” CE algorithm enjoys O(n²(log(1/ε)+log(1/(1−q)))) upper bound on the number of function evaluations. (2) The IE algorithm solves the problem in the residual sense, i.e., computes x such that 6f(x)−x6⩽δ, with O(n ln(1/δ)) function evaluations for every q⩽1.     

空间几何常数与集值非扩张映射的不动点

本文利用凸刻画系数和正规结构系数,詹姆斯型常数和García-Falset系数之间的关系式,得到了空间上集值非扩张映射存在不动点的一些充分条件,这些结论不仅改进了一些文献中的结果,而且也对一些公开问题给出了解答.     

Continuous Approximations of Multivalued Mappings and Fixed Points

In the present paper, we prove a fixed-point theorem for completely continuous multivalued mappings defined on a bounded convex closed subset X of the Hilbert space H which satisfies the tangential condition , where T _X (x) is the cone tangent to the set X at a point x. The proof of this theorem is based on the method of single-valued approximations to multivalued mappings. In this paper, we consider a simple approach for constructing single-valued approximations to multivalued mappings. This approach allows us not only to simplify the proofs of already-known theorems, but also to obtain new statements needed to prove the main theorem in this paper.__________Translated from Matematicheskie Zametki, vol. 78, no. 2, 2005, pp. 212–222.Original Russian Text Copyright © 2005 by B. D. Gel’man.     

Multivalued Homotopy on an Ordered Set,Fixed and Coincidence Points of Mappings,and Applications in Game Theory

Mathematical Notes - The article develops results of the authors’ previous papers on the topic. The notion of the homotopy of a multivalued mapping of an ordered set is introduced. We study...