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1.
拓扑遍历与拓扑双重遍历   总被引:24,自引:1,他引:23  
杨润生 《数学学报》2003,46(3):555-560
令X为紧致度量空间,f:X→X为连续映射,U,V为X的任意非空开集,若{n>0|fn(U)∩V≠ )为正上密度集,则称f拓扑遍历.f拓扑双重遍历意味着f×f拓扑遍历.本文在[2]的基础上进一步讨论拓扑遍历与拓扑双重遍历映射的性质.  相似文献   

2.
本文利用模糊滤子的m-收敛概念对模糊拓扑空间的最小Hausdorff拓扑的特征进行了刻画,对模糊网的m-收敛与模糊拓扑空间的m-紧之间的关系以及最小Hausdorff拓扑与m-紧之间的关系进行了研究。  相似文献   

3.
在模糊化拓扑空间基础上,放宽了模糊化拓扑结构的公理体系,引入模糊化弱拓扑和模糊化预拓扑的概念,并且讨论了它们构成的范畴和模糊化拓扑空间范畴的关系.结果表明,模糊化拓扑空间范畴既是模糊化弱拓扑空间范畴的双余反射满子范畴,又是模糊化预拓扑空间范畴的双余反射满子范畴.  相似文献   

4.
拓扑剩余格     
利用剩余格L中滤子系统F={F_i:i∈Λ}诱导的拓扑τ_F,证明了(L,τ_F)是拓扑剩余格,给出拓扑剩余格(L,τ_F)中任意一个非空集合的闭包的表达形式,并且在给定的一些特殊的条件下证明了(L,τ_F)是Hausdorff空间.  相似文献   

5.
最强Orlicz-Pettis拓扑   总被引:4,自引:0,他引:4  
引进了lp(p≥1)空间的子集是本性紧概念,借此给出了抽象对偶系统(E,F)中最强Orlicz-Petits拓扑SOP(E,F)以及产生该拓扑的最大映射集族的表示.利用此结果搞清楚了现有两种Orlicz-Petits拓扑即Dierolf拓扑(M)和Twed-dle拓扑(E,T’)的确切意义以及它们之间的相互关系.指出了的最大性所蕴涵的理论意义和应用价值.证实了σ(F,E)-条件紧集和σ(F,E)-可数紧集都含于中。进而实质性地改进了矢位测度论中的Graves-Rness定理、抽象函数论中的Thomas定理等重要结果.  相似文献   

6.
设E是一个A rch im edean R iesz空间,a∈E,Φ≠A E,则有如下的两个结论:1)由a生成的a-拓扑空间E是一个H ausdorff空间;2)若以下条件之一成立,则由A生成的A-拓扑空间E是一个H ausdorff空间:(a)子集{a:a∈A}有上界;(b)E具有强单位元;(c)若E=C(X),其中X是一个局部紧H ausdorff空间.  相似文献   

7.
拓扑遍历映射   总被引:17,自引:2,他引:15  
杨润生 《数学学报》2001,44(6):1063-106
本文研究紧致度量空间上拓扑遍历自映射的性质、判定及与混沌的关系.  相似文献   

8.
Fuzzy拓扑体   总被引:1,自引:0,他引:1  
引入了 Fuzzy拓扑体的定义 ,研究了它的性质 ,得到了借助于θλ的重域系及开重域基刻画 Fuzz拓扑体的充要条件 ;为 Fuzzy拓扑体理论研究提供了框架和工具 .  相似文献   

9.
双拓扑群     
由J.C.Kelley首创的双拓扑空间理论七十年代中期以来得到迅速发展。在此背景下,本文建立双拓扑群概念,以拓广拓扑群的研究。 定义 设(X,·)为群,(X,)为双拓扑空间。(X,·,)关于为拓扑群系指函数f(x,y)=xy~(-1)视为f:(X,)×(X,)→(X,)是连续的,平行地可定义(X,)关于为拓扑群。若上述两者皆成立,则称(X,·,)为双拓扑群。  相似文献   

10.
1.绪言一般拓扑学中有时会发生这样的问题:给定集合S及S上的一组变换{r_i},i=1,2,…,能不能在S上建立一个拓扑结构(一般不是最弱的(trivial)也不是最强的(discrete)拓扑结构),把S变成一个空间,并且使得所有的r_i都是这个空间的连续变换。特别,D. Ellis证明了的结果是:对于任意的集合S和S上的变换r,能够在S上引进一个拓扑结构,叫做轨道拓扑,把S变成一个T_1空间Sr;使得r只要是有限到  相似文献   

11.
Xuxin Mao  Luoshan Xu 《Order》2006,23(4):359-369
In this paper, posets which may not be dcpos are considered. In terms of the Scott topology on posets, the new concept of quasicontinuous posets is introduced. Some properties and characterizations of quasicontinuous posets are examined. The main results are: (1) a poset is quasicontinuous iff the lattice of all Scott open sets is a hypercontinuous lattice; (2) the directed completions of quasicontinuous posets are quasicontinuous domains; (3) A poset is continuous iff it is quasicontinuous and meet continuous, generalizing the relevant result for dcpos. Supported by the NSF of China (10371106, 10410638) and by the Fund (S0667-082) from Nanjing University of Aeronautics and Astronautics.  相似文献   

12.
In this paper, some properties of order topology and bi-Scott topology on a poset are obtained. Order-convergence in posets is further studied. Especially, a sufficient and necessary condition for order-convergence to be topological is given for some kind of posets.  相似文献   

13.
本文给出了连续偏序集的一个刻画定理及相应的代数偏序集刻画定理.进一步得出连续偏序集P关于其Scott拓扑是局部紧的,而且OFilt(P)是一个domain.这推广了关于dcpo的对应结果.  相似文献   

14.
In this paper, the concept of strongly continuous posets (SC-posets, for short) is introduced. A new intrinsic topology—the local Scott topology is defined and used to characterize SC-posets and weak monotone convergence spaces. Four notions of continuity on posets are compared in detail and some subtle counterexamples are constructed. Main results are: (1) A poset is an SC-poset iff its local Scott topology is equal to its Scott topology and is completely distributive iff it is a continuous precup; (2) For precups, PI-continuity, LC-continuity, SC-continuity and the usual continuity are equal, whereas they are mutually different for general posets; (3) A T0-space is an SC-poset equipped with the Scott topology iff the space is a weak monotone convergence space with a completely distributive topology contained in the local Scott topology of the specialization order.  相似文献   

15.
The Hom complex of homomorphisms between two graphs was originally introduced to provide topological lower bounds on the chromatic number. In this paper we introduce new methods for understanding the topology of Hom complexes, mostly in the context of Γ-actions on graphs and posets (for some group Γ). We view the Hom(T, ⊙) and Hom(⊙, G) complexes as functors from graphs to posets, and introduce a functor ()1 from posets to graphs obtained by taking atoms as vertices. Our main structural results establish useful interpretations of the equivariant homotopy type of Hom complexes in terms of spaces of equivariant poset maps and Γ-twisted products of spaces. When P:= F(X) is the face poset of a simplicial complex X, this provides a useful way to control the topology of Hom complexes. These constructions generalize those of the second author from [17] as well as the calculation of the homotopy groups of Hom complexes from [8].  相似文献   

16.
In this paper, some properties of prime elements, pseudoprime elements, irreducible elements and coatoms in posets are investigated. We show that the four kinds of elements are equivalent to each other in finite Boolean posets. Furthermore, we demonstrate that every element of a finite Boolean poset can be represented by one kind of them. The example presented in this paper indicates that this result may not hold in every finite poset, but all the irreducible elements are proved to be contained in each order generating set. Finally, the multiplicative auxiliary relation on posets and the notion of arithmetic poset are introduced, and some properties about them are generalized to posets.  相似文献   

17.
In this paper, posets which may not be dcpos are considered. The concept of embedded bases for posets is introduced. Characterizations of continuity of posets in terms of embedded bases and Scott topology are given. The main results are:
(1)
A poset is continuous iff it is an embedded basis for a dcpo up to an isomorphism;
(2)
A poset is continuous iff its Scott topology is completely distributive;
(3)
A topological T0 space is a continuous poset equipped with the Scott topology in the specialization order iff its topology is completely distributive and coarser than or equal to the Scott topology;
(4)
A topological T1 space is a discrete space iff its topology is completely distributive.
These results generalize the relevant results obtained by J.D. Lawson for dcpos.  相似文献   

18.
谢琳 《数学学报》1999,42(3):505-510
本文讨论了那样一些DCPO(即定向完备偏序集)的刻划问题,它们在赋以Scott开滤子拓扑后,其拓扑空间的开集格是连续格。该问题也是由LawsonJD。与MisloveM.提出的一系列公开问题中的一个[1]。  相似文献   

19.
连续偏序集及其Smyth幂的几个等权定理   总被引:2,自引:1,他引:1  
推广连续D om a in的权的概念到连续偏序集上,探讨连续偏序集的权、相应内蕴拓扑的权、定向完备化的权以及Sm yth幂D om a in的权间的关系。得到了几个等权定理:(1)连续偏序集的权与其上Scott拓扑、L aw son拓扑的权相等;(2)连续偏序集的权与其定向完备化的权相等;(3)无穷连续D om a in的权与其Sm yth幂D om a in的权相等;(4)有限D om a in的权小于或等于它的Sm yth幂D om a in的权。  相似文献   

20.
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