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S -次仿紧空间
引用本文:何兆容,石鹏飞,孙文.S -次仿紧空间[J].佳木斯工学院学报,2014(6):947-949.
作者姓名:何兆容  石鹏飞  孙文
作者单位:成都理工大学管理科学学院,四川成都610059
基金项目:安徽省高等学校省级优秀青年人才基金项目(2010SQRL158).
摘    要:针对一些广义仿紧空间以及拓扑空间中半开集和半闭集的性质,本文将次仿紧空间的一些结论推广到半闭集的条件下,新定义并研究S -次仿紧空间的基本性质。首先给出一些基本的定义和定理,然后在此基础上定义S-次仿紧空间,最后得出一些主要结果:(1)空间X是S-次仿紧空间,则X的每一开覆盖U,存在半开加细覆盖序列{Vn}n∈N使对每一x∈X,存在n∈N,使ord(x,Vn)=1,这里(ord(x,Vn)=|{V:V∈Vn,x∈V}|);(2)空间X是S-次仿紧空间,则X的每一开覆盖具有σ垫状加细覆盖;(3)如果(X,Fa)是S-次仿紧空间,则(X,F)也是S-次仿紧空间,并给出相应的证明。

关 键 词:S-次仿紧  S-仿紧  半开覆盖  半闭覆盖  垫状

S-subparacompact Spaces
Authors:HE Zhao-rong  SHI Peng-fei  SUN Wen
Affiliation:( College of Management Science, Chengdu University of Tedmology, Chengdu 610059, China)
Abstract:Based on a series of generalized paracompact spaces and the properties of semi -open and semi-closed sets in topological spaces , some conclusions of sub -paracompact spaces were spread to semi -closed sets.The definition of S -subparacomact space was given and its basic properties was studied .Some basic defi-nitions and theorems in topological spaces were given first , and then the definition of S -subparacompact space was introduced .Some main results were obtained as follows: ( 1 ) Let X be a S-subparacompact space , then each open cover U of X has a semi-open n∈N refinements{Vn}n∈N and for every x∈X , there exists a positive integrity such that only belongs to one set of Vn ,i.e.ord( x,Vn ) =1 .(2) If X is a S-subparacompact space . Then each open cover U of X has a refinement which isσ-cushioned in the family U .(3) Suppose (X,Tα) is a S-subparacompact space.Then the space (X,T) is S-subparacompact.At same time, their corresponding proofs are presented .
Keywords:S - paracompact  S - subparacompact  semi - open refinement  semi - closed refinement  be cushioned in
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