Fuzzy拓扑空间中的紧性(Ⅰ)——定义和特征(英文)

本文在引入了一复盖的概念之后,定义了(?)一紧性,得出了关于闭集中心族,F-网与F-滤子的(?)-紧性的特微,以及A1exander子基定理。并进一步定义了S-紧,L-紧,I-紧和F-紧性,讨论了这些概念之间的关系。设A,B∈I~Y为X中的Fuzzy集,我们称有序对〈A,B〉为X中的一个(?)一集。定义1 设(X,F)是一个Fuzzy拓扑空间,〈A,B〉为X中的一个(?)一开集,P∈P_*(X)。如果〈A,B〉是P的邻域,则我们说〈A,B〉覆盖P。一个开(?)一集族(?)={〈A_λ,B_λ〉:λ∈Λ}称为X的一个(?)-覆盖,当且仅当对于任一P∈IP_*(X),存在λ∈Λ,使〈A_λ,B_λ>覆盖P。定义2 Fuzzy拓扑空间(X,F)称为(?)-紧的,当且仅当每个(?)覆盖都有有限子(?)-覆盖。定理1 Fuzzy拓扑空间(X,F)是(?)-紧的,当且仅当每个闭(?)-集构成的有限中心族都是中心族。定理2 Fuzzy拓扑空间(X,F)是(?)-紧的,当且仅当X中的每个F-网或者(?)-滤子都有聚点。定理5 设S为Fuzzy拓扑空间(X,F)的一个子基,若每个(?)覆盖(?)={〈A_λ,B_λ〉:A_λ,B_λ∈S,λ∈Λ}都有有限子覆盖,则(X,F)是(?)-紧的。     

关于Lowen空间指数对象的一点注记

L-拓扑空间(X,△)称为一Lowen空间若△有一组由层特征函数构成的基,即△中形如a∧U,a∈L,U∈X的元素构成△的一组基.若L=[0,1],则(X,△)是一Lowen空间当且仅当(X,△)是一Lowen意义下的fzzy邻域空间.通过在函数空间上引入适当的L-拓扑结构,证明了若0∈L是一素元并且Lowen空间(X,△)的开集格是一连续格,则(X,△)是Lowen空间范畴中一指数对象.特别地,若一fuzzy邻域空间的开集格连续,则它是FNS中一指数对象.     

蕴涵格及其Fuzzy拓扑表现定理

以L－Lindenbaum代数为背景,引入了蕴涵格与正则蕴涵格的概念,讨论了其基本性质,引入了Fuzzy蕴涵空间的概念,为点集拓扑学中零维空间概念的推广．建立了正则蕴涵格的Fuzzy蕴涵空间表现定理,以此为基础可以给出著名的Stone表现定理的另一种证明．     

格L~x上的点式距离函数

本文给出了L-Fuzzy集上的p.q(p.)度量对应的点式距离函数(不同于[2]的点式刻划),其满足的公理不但与分明集的度量公理相协调,而且体现了分子集的有序性,颇有格上度量的特色.文中X和L总表非空集和Fuzzy格,J(L)表全体L的非0既约元所构成之集,β(A)表L的元A对虚的极小集[3](β(0)=φ)、“(?)”表格上的way below关系。若以小写英文字母a表J(L)的元,则a(?)A等价于a∈β(A)。     

内射拓扑分子格

本文证明了任给T_O拓扑分子格(L,η),以下三条等价:(1)(L,η)为正则内射拓扑分子格;(2)L为完备集环且其完备余素元集ht(L)形成一连续格,余拓扑η为该连续格ht(L)上的Scott闭集格;(3)存在T_O内射拓扑空间(X,Τ),(L,η)同胚于(P(X),Τ~c)在拓扑分子格范畴中的Sober化。此外,还给出了正则内射拓扑分子格、(一般)内射拓扑分子格以及正则内射分子格的一般结构。作为应用,重新证明了有指数元的拓扑分子格的结构。     

完全分配格的谱论与拓扑分子格

本文借助于完全分配格的谱理论是首先证明分子格范畴同构于某连续偏序集范畴子范畴,然后利用上述同构,证明分子格上余拓扑同构于其中分子之集上。与分子序密切相关的某分明拓扑,从而就给“重域”“远域”这两个基本概念以合理解释,并证明许多拓扑分子格性质的研究可以化为相应的拓扑空间性质的研究.“重域”概念的引入,使 fuzzy 拓扑学的研究发生了根本变化,导致了有点派的兴起。而“远域”的引入,则导致因更广的拓扑分子格理论的产生,从而把 Fuzzy 拓扑为学纳入了拓扑格的范畴.本文中我们首先建立分子格范畴与连续偏序集范畴某子范畴的同构,从而把二者的研究紧密结合起来,然后借助上述同构把拓扑分子格中的问题的研究化为连续偏序集中问题去考虑,通过这种转化,我们将会看到,“重域”,“远域”等基本概念确为 fuzzy 拓扑学,拓扑分子格中唯一合理的点与集合的邻属关系,而择一原理这条fuzzy 拓扑学中的基本原理成立的原因也就变得很清楚。本文中凡未定义的概念请参看[4].     

杨忠道定理和樊畿定理在广义拓扑分子格中的推广

1979年,作者建立了拓扑分子格理论,它以一般拓扑学和不分明拓扑学为特例。最近,作者又把这一理论推广到广义拓扑分子格,从而扩大了它的应用范围。在本文中,我们把关于导集的杨忠道定理及关于连通性的樊畿定理推广到广义拓扑分子格中。在本文中,L恒表示具有最小元0,最大元1及一个逆序对合对应的完全分配格。     

L-值随机变量

研究L-值随机变量(其中L是闭集格或分子生成格与格上拓扑学有关)。受到已有文献中研究L-拓扑空间的思想、方法和技巧的启发,定义FLc(Rn)={A∈LRn对每个余素元,α{x∈Rn A(x)≥α}是Rn中的非空紧集}上一个分明拓扑TFLc以及L-子集族上的三种度量。在此基础上定义几种L-值随机变量并讨论了它们的初步性质。     

Fuzzy集论中邻属关系的分析

重域系构造在不分明拓扑的研究中已取得相当的成功,在文献[6]中我们给出了几组互相等价的公理系,从拓扑学与Fuzzy集论角度刻划了重域系构造,因为不分明拓扑空间中邻近构造是由不分明点与不分明集之间的邻属关系决定的,本文就从Fuzzy集论角度分析这个邻属关系。我们给出了直观且比较明显的四条原则并证明满足这些原则的唯一的邻属关系就是相重关系,这个相重关系在不分明拓扑学中相应于重域系构造。     

拓扑分子格范畴的乘积与上积

本文在樊太和关于分子格范畴的积运算的基础上,研究了以拓扑分子格(TML)为对象,连续的广义序同态(CGOH)为态射的范畴中的乘积与上积,它们是一般拓扑学、Fuzzy拓扑学中积(和)空间概念的推广。     

On separation axioms in fuzzy topological spaces,fuzzy neighborhood spaces,and fuzzy uniform spaces

A certain number of separation axioms for fuzzy topological spaces are provided, all of which are good extensions of the topological (T₀), (T₁), or (T₂). All valid implications between the different axioms are studied and counterexamples are given for the nonvalid ones.     

Separation and Epimorphisms in Quasi-Uniform Spaces

We study some categorical aspects of quasi-uniform spaces (mainly separation and epimorphisms) via closure operators in the sense of Dikranjan, Giuli, and Tholen. In order to exploit better the corresponding properties known for topological spaces we describe the behaviour of closure operators under the lifting along the forgetful functor T from quasi-uniform spaces to topological spaces. By means of appropriate closure operators we compute the epimorphisms of many categories of quasi-uniform spaces defined by means of separation axioms and study the preservation (reflection) of epimorphisms under the functor T.     

S-Regular and S-Normal Spaces

In this paper s-regular and s-normal spaces are characterized using semi-T₀-identification spaces, topological sums of s-regular and s-normal spaces are examined, and the relationships between s-regular, s-normal, and other separation axioms are further examined.     

Some localized separation axioms and their implications

In a topological spaceX, a T₂-distinct pointx means that for anyyX xy, there exist disjoint open neighbourhoods ofx andy. Similarly, T₀-distinct points and T₁distinct points are defined. In a T_i-distinct point-setA, we assume that eachxA is a T _i -distinct point (i=0, 1, 2). In the present paper some implications of these notions which localize the T _i -separation axioms (i=0, 1, 2) requirement, are studied. Suitable variants of regularity and normality in terms of T₂-distinct points are shown hold in a paracompact space (without the assumption of any separation axioms). Later T₀-distinct points are used to give two characterizations of the R _D -axiom.¹ In the end, some simple results are presented including a condition under which an almost compact set is closed and a result regarding two continuous functions from a topological space into a Hausdorff space is sharpened. A result which relates a limit pointv to an -limit point is stated.     

Bitopological and topological ordered k-spaces

Domain theory, in theoretical computer science, needs to be able to handle function spaces easily. It also requires asymmetric spaces, and these are necessarily not T₁. At the same time, techniques used with the higher separation axioms are useful there (see [Topology Appl. 199 (2002) 241]). In order to handle all these requirements, we develop a theory of k-bispaces using bitopological spaces, which results in a Cartesian closed category. The other well-known way to combine asymmetry and separation is ordered topological spaces [Nachbin, Topology and Order, Van Nostrand, 1965]; we define the category of ordered k-spaces, which is isomorphic to that found among bitopological spaces.     

Fell topology on the space of functions with closed graph

LetX andY beT ₁ topological spaces andG(X, Y) the space of all functions with closed graph. Conditions under which the Fell topology and the weak Fell topology coincide onG(X,Y) are given. Relations between the convergence in the Fell topologyτF, Kuratowski and continuous convergence are studied too. Characterizations of a topological spaceX by separation axioms of (G(X, R), τF) and topological properties of (G(X, R), τF) are investigated.     

Certain properties of bitopological spaces

Some connections and interrelations between T_i-separation axioms (i=1,2,3) for bitopological spaces are considered. In particular, four different versions of the definition of the pairwise Hausdorff separation axion are discussed. Bibliography: 3 titles. Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 231, 1995, pp. 135–140. Translated by O. A. Ivanov.     

Separation properties at p for the topological category of Cauchy spaces

An explicit characterization of each of the separation properties?T _i , i=0,1, $\mathop {\mathrm {Pre}}\nolimits T_{2}$ , and T ₂ at a point p is given in the topological category of Cauchy spaces. Moreover, specific relationships that arise among the various?T _i , i=0,1, $\mathop {\mathrm {Pre}}\nolimits T_{2}$ , and T ₂ structures at p are examined in this category. Finally, we investigate the relationships between generalized separation properties and separation properties at a point p in this category.     

The Algebraic K-Theory of Operator Algebras

We the study the algebraic K-theory of C *-algebras, forgetting the topology. The main results include a proof that commutative C*-algebras are K-regular in all degrees (that is, all theirN ^T K _iand extensions of the Fischer-Prasolov Theorem comparing algebraic and topological K-theory with finite coefficients.