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21.
This paper contains a fixed point theorem for six self maps in Menger space. Our result generalizes and extends many known results in Menger spaces and metric spaces.  相似文献   
22.
A well‐known conjecture of Erd?s states that given an infinite graph G and sets A, ? V(G), there exists a family of disjoint A ? B paths ?? together with an A ? B separator X consisting of a choice of one vertex from each path in ??. There is a natural extension of this conjecture in which A, B, and X may contain ends as well as vertices. We prove this extension by reducing it to the vertex version, which was recently proved by Aharoni and Berger. © 2005 Wiley Periodicals, Inc. J Graph Theory 50: 199–211, 2005  相似文献   
23.

We prove that every finitely generated group acts effectively on the universal Menger curve.

  相似文献   

24.
A functional Menger system is a set of n-place functions containing n projections and closed under the so-called Menger's composition of n-place functions. We give the abstract characterization for subsets of these functional systems which contain functions having one common fixed point.  相似文献   
25.
An abstract characterization of sets of some partial functions from An to A closed with respect to the Menger's and Mann's superpositions and a quasicomplementation is presented.  相似文献   
26.
本文在Menger概率度量空间中引进Caristi型混合不动点概念,得到两个混合不动点定理和两个集值映象序列的公共混合不动点定理,我们的定理改进和推广了Caristi不动点定理及相关的近期重要结果.  相似文献   
27.
A new contraction principle in menger spaces   总被引:2,自引:0,他引:2  
In the present work we introduce a new type of contraction mapping by using a specific function and obtain certain fixed point results in Menger spaces. The work is in line with the research for generalizing the Banach's contraction principle. We extend the notion of altering distance function to Menger Spaces and obtain fixed point results.  相似文献   
28.
PM-空间中混合压缩的不动点定理与重合点定理   总被引:2,自引:2,他引:0  
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.  相似文献   
29.
朱传喜  罗雷 《应用数学》2012,25(1):47-53
在半序概率度量空间中,引入φ-μ-混合单调算子的概念.同时,构建一些新的条件,并采用半序技巧和分布函数的性质获得了φ-μ-混合单调算子方程组的解.  相似文献   
30.
董锡杰  胡一帆  吴玉莹 《中国物理 B》2010,19(1):13601-013601
Depth profiled positronium (Ps) annihilation lifetime spectroscopy (PALS) is an extremely useful probe of the pore characteristics in nanoporous low-dielectric (low-k) constant thin films. PALS has also been considered as a potential probe to investigate diffusion barrier integrity and the structural changes of porous low-k films during their integration with Cu. Hence, it is essential to understand the diffusion behaviour of positronium/Cu atoms in the films. In this work, based on the fact that porous materials possess characteristics of statistical self-similarity, a fractal model, the Menger sponge model, has been applied to simulate the structure of a promising dielectric, porous methylsilsesquioxane (MSQ) films. The diffusion behaviour of Ps out of the fractal model and into the surrounding vacuum is studied by means of the diffusion equation and traditional advective-diffusive theory. Predictive results from our model show good agreement with measurement data.  相似文献   
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