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11.
In the present paper we use a control function to define a generalized contraction in Menger spaces and obtain a unique fixed point theorem. The work is in line with the research for developing probabilistic contractions with the help of control functions and related fixed point results. We have given an example to which our theorem is applicable. Some corollaries are also discussed.  相似文献   
12.
We study M-separability as well as some other combinatorial versions of separability. In particular, we show that the set-theoretic hypothesis b=d implies that the class of selectively separable spaces is not closed under finite products, even for the spaces of continuous functions with the topology of pointwise convergence. We also show that there exists no maximal M-separable countable space in the model of Frankiewicz, Shelah, and Zbierski in which all closed P-subspaces of ω* admit an uncountable family of nonempty open mutually disjoint subsets. This answers several questions of Bella, Bonanzinga, Matveev, and Tkachuk.  相似文献   
13.
Let be the -dimensional universal Menger compactum, a -set in and a metrizable zero-dimensional compact group with the unit. It is proved that there exists a semi-free -action on such that is the fixed point set of every . As a corollary, it follows that each compactum with can be embedded in as the fixed point set of some semi-free -action on .

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14.
Using the idea of Atanassov, we define the notion of intuitionistic Menger spaces as a netural generalizations of Menger spaces due to Menger. We also obtain a new generalized contraction mapping and utilize this contraction mapping to prove the existance theorems of solutions to differential equations in intuitionistic Menger spaces.  相似文献   
15.
I.IntroductionandPreliminariesInl976,CaristiprovedtheCaristi'sfixedpointtheoreminIll.Becausethistheoremdoesnotrequirethecontinuityofthemapping.ittindsapplicationsinmanyfields.Inl99l,S.S.Changetal.l'l,broughtforwardCaristi'sfixedpointtheoremandEkeland'svar…  相似文献   
16.
Let G be a graph. The connectivity of G, κ(G), is the maximum integer k such that there exists a k-container between any two different vertices. A k-container of G between u and v, Ck(u,v), is a set of k-internally-disjoint paths between u and v. A spanning container is a container that spans V(G). A graph G is k-connected if there exists a spanning k-container between any two different vertices. The spanning connectivity of G, κ(G), is the maximum integer k such that G is w-connected for 1≤wk if G is 1-connected.Let x be a vertex in G and let U={y1,y2,…,yk} be a subset of V(G) where x is not in U. A spanningk−(x,U)-fan, Fk(x,U), is a set of internally-disjoint paths {P1,P2,…,Pk} such that Pi is a path connecting x to yi for 1≤ik and . A graph G is k-fan-connected (or -connected) if there exists a spanning Fk(x,U)-fan for every choice of x and U with |U|=k and xU. The spanning fan-connectivity of a graph G, , is defined as the largest integer k such that G is -connected for 1≤wk if G is -connected.In this paper, some relationship between κ(G), κ(G), and are discussed. Moreover, some sufficient conditions for a graph to be -connected are presented. Furthermore, we introduce the concept of a spanning pipeline-connectivity and discuss some sufficient conditions for a graph to be k-pipeline-connected.  相似文献   
17.
Abstract characterizations of relations of nonempty intersection, inclusion end equality of domains for partial n-place functions are presented. Representations of Menger (2, n)-semigroups by partial n-place functions closed with respect to these relations are investigated.  相似文献   
18.
两个完备Menger PM-空间上复合映射的公共不动点定理   总被引:1,自引:1,他引:0  
概率度量空间中映射不动点问题的研究是非线性算子问题研究的重要组成部分。主要讨论两个不同的完备M enger PM-空间上复合映射的公共不动点存在性及唯一性,并讨论了迭代收敛问题,给出了几个相关定理和推论。  相似文献   
19.
Menger PM-空间中,引入广义β-可容许映射的概念。在不要求两映射可交换的情况下,利用迭代法,建立了广义β-可容许映射的二元重合点定理。获得了一些新的结果,推广和改进了相关文献中的不动点定理和二元重合点定理。最后,给出了主要结果的一个应用。  相似文献   
20.
By the use of recursion relations and analytic techniques we deduce general analytic results pertaining to the electrostatic potential, moments, and Fourier transform of exactly self-similar fractal and multifractal charge distributions. Three specific examples are given: the binomial distribution on the middle-third Cantor set, which is a multifractal distribution, the uniform distribution on the Menger sponge, which illustrates the added complication of higher dimensionality, and the uniform distribution on the von Koch snowflake, which illustrates the effect of rotations in the defining transformations.  相似文献   
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