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1.
g—可度量空间的完备逆象   总被引:2,自引:0,他引:2  
林寿  陈焕然 《数学进展》1995,24(4):338-341
本文的主要目的是建立g-可度量空间的两个映射定理:(1)g-可度量空间是度量空间的商紧映象;(2)g-可度量空间的完备逆象若具有Gδ-对角线,那么它是g-可度量空间。  相似文献   

2.
李进金  李克典 《数学杂志》2005,25(6):637-640
本文利用序列覆盖分层强紧映射,建立了( )-空间,g-可度量空间与特定的度量空间的关系,这是对Alexandroff的部分问题的肯定回答。  相似文献   

3.
林寿 《东北数学》1995,11(3):343-348
  相似文献   

4.
完备和紧度量空间中的不动点   总被引:4,自引:1,他引:3  
利用实函数性质,建立了两类度量空间中的几个不动点定理,推广了Fisher的有关定理。  相似文献   

5.
In this paper,the metric space(A, ρ) induced by finite measure space(X,A,μ) is introduced completeness and researched.  相似文献   

6.
本文将给出k-半分层空间的若干度量化定理以及分层空间和σ-空间的度量化定理.  相似文献   

7.
夏大峰  符美芬  江波 《数学进展》2007,36(4):415-420
本文给出了具有对称的集合上两个自映射有唯一共同不动点的充要条件.同时,还给出了完备度量空间上两个自映射有共同唯一不动点的条件.  相似文献   

8.
本文通过构造特殊的映射和函数,利用压缩定理,研究完备序度量空间中耦合公共点的存在性和唯一性,改进了最近的一些结果.  相似文献   

9.
距离空间X上,以M(X)记定义在X的Borel域上的具有有界支撑的概度测度全体,R(X)记M(X)中所有Radon测度,M(X),R(X)均赋予Hutchison度量,本文得到:R(X)完备当且仅当X完备且有界,若X可分,则:M(X)完备当且仅当X完备且有界。  相似文献   

10.
11.
Perfect Preimages of Some Spaces   总被引:2,自引:0,他引:2  
PerfectPreimagesofSomeSpaces¥(林寿)LinSnou(DepartmentofMathematics,NingdeTeachers'College,Ningle,Fujina,352100)Abstract:InthisP...  相似文献   

12.
ImagesandPreimagesofD_0Spaces¥DaiMumin;ChenHaiyan(DepartmentofMath.andInformationScience,UniversityofGuangxi)Abstract:Thispep?..  相似文献   

13.
It is proved that if X is a normal space which admits a closed fiberwise strongly zero-dimensional continuous map onto a stratifiable space Y in a certain class (an S-space), then IndX = dimX. This equality also holds if Y is a paracompact σ-space and ind Y = 0. It is shown that any closed network of a closed interval or the real line is an S-network. A simple proof of the Kateˇ tov–Morita inequality for paracompact σ-spaces (and, hence, for stratifiable spaces) is given.  相似文献   

14.
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16.
关于完全仿紧空间的一些刻画   总被引:3,自引:0,他引:3  
朱培勇 《数学进展》2000,19(4):301-306
本文在T1正则的条件下得到了完全仿紧空间的一些等价刻画,并利用所得到的刻画证明了这类空间的一个可数乘积定理。  相似文献   

17.
This paper deals with a new class of perfect Frèchet spaces which can be obtained by interpolation of echelon spaces: lp,q[am,n]. We determine the reflexive, Montel, Schwartz, totally reflexive, totally Montel and nuclear spaces lp,q[am,n]. We also derive results on closed subspaces on the spaces (lp,q)(N).  相似文献   

18.
设a_γ=(a,γ)和b_δ=(b,δ)是两个原像,且b■a.通过集运算,得到a_γ和b_δ关于occlusion运算能交换的充要条件,特别得到在δ■γ的情形下aγ和bδ能交换的充要条件,并给出正反两方面的例子.  相似文献   

19.
We point out that the product of two fuzzy closed sets of smooth fuzzy topological spaces need not be fuzzy closed with respect to the the existing notion of product smooth fuzzy topology. To get this property, we introduce a new suitable product smooth fuzzy topology. We investigate whether F1×F2 and (F,H) are weakly smooth fuzzy continuity whenever F1, F2, F and H are weakly smooth fuzzy continuous. Using this new product smooth fuzzy topology, we define smooth fuzzy perfect mapping and prove that composition of two smooth fuzzy perfect mappings is smooth fuzzy perfect under some additional conditions. We also introduce two new notions of compactness called Q-compactness and Q-α-compactness; and discuss the compactness of the image of a Q-compact set (Q-α-compact set) under a weakly smooth fuzzy continuous function ((α,β)-weakly smooth fuzzy continuous function).  相似文献   

20.
We compute the minimal number of roots of the equation $f(x) = c$ for a map $f$ belonging to a given homotopy class of maps between closed (not necessarily oriented) surfaces.  相似文献   

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