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1.
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   

2.
给出了随机变量 X1,X2 ,X3 ,X4 每三个相互独立 ,但 X1±X2 与 X3 ± X4 不相互独立的例子 ,以及 X1,X2 ,X3 每两个相互独立 ,但 X1± X2 与 X3 不相互独立的例子 .  相似文献   

3.
弱拓扑和强可容许拓扑之间的一个关系   总被引:2,自引:0,他引:2  
孙立民 《数学杂志》2003,23(2):141-145
本文对局部凸空间X及其对偶X′,建立了弱拓扑σ(X,X′)和强拓扑β(X,X′)之间的一个新关系,改进了有关(X,X′)--可容许拓扑全体上的不变性结果。  相似文献   

4.
侯吉成 《数学进展》2002,31(3):271-274
设X是拓扑空间,CL(X)表示X的所有非空闭子集的族,本文得到了下述结果:在CL(X)上的Fell-拓扑是伪肾的当且仅当X是feebly-紧或者非局部紧或者非σ-紧,由此得到了对于伪紧性不是闭遗传的两类新的拓扑空间。  相似文献   

5.
本文给出具有散子代数的BCI代数的条件,讨论了L(X)为X的理想的BCI代数,完全刻划了每个子代数都是理想的BCI代数。  相似文献   

6.
一类广义变换半群的格林关系   总被引:1,自引:0,他引:1  
设X是一个全序集,E是X上的一个凸等价关系.令 OE(X)={f∈TE(X):Ax,y∈X,x≤y→f(x)≤f(y)), 其中TE(X)是E-保持变换半群.对于取定的θ∈OE(X),在OE(X)上定义运算fog=fθg,使OE(X)成为广义半群OE(X;θ).对于有限全序集X上的凸等价关系E,本文刻画了广义半群OE(X;θ)的正则元,描述了这个半群的格林关系.  相似文献   

7.
假设S(X)是Banach空间X的单位球面,作引进了四个新的几何参数:Jε(X)=sup{βε(x),x∈S(X)},jε(X)=inf{βε(x),x∈S(X)},Gε(X)=sup{αε(x),x∈S(X)},gε(X)=inf{αε(x),x∈S(S)},其中≤ε≤1,βε(x)=sup{min{‖x εy‖,‖x-εy‖,y∈S(X)}},αε(x)=inf{max{‖x εy‖,‖x-εy‖,y∈S(X)}},讨论了这些参数的性质,本主要结果是:如果主要结果是:如果有一个ε,0≤ε≤1,使得Jε(X)<1 ε/2或gε(X)>1 ε/3,那末X有一至正规结构。  相似文献   

8.
正规六边形和更广泛具有正规结构的Banach 空间   总被引:1,自引:1,他引:0  
高继 《数学杂志》2000,20(3):241-248
假设X是一个实Banach空间,S(X)是单位球面。作者引进了一个新的几何参数(H(X),讨论了H(X)和Neumann-Jordan常数CNJ(X)R 性质以及H(X)和其他几何常数的关系,本文主要结果是:H(X)〈2或CNJ(X)〈4/5一致正规结构。  相似文献   

9.
LI Yi-jun 《数学季刊》2006,21(2):196-201
To obtain a better Vinogradov's bound, assistant function with two or three zeros and all Dirichlet's characters has been evaluated. Assistant function g(X1,X2,X3,X4)with four zeros and all nonprincipal characters but X1X2X3X4 is constructed and evaluated in the paper. And the constant obtained is 8.395 511 841 994.  相似文献   

10.
AnExampleonOperatorIdealsZhongHuaijie(钟怀杰)(DepartmentofMathematics,FujianNormalUniversity,Fuzhou,350007)Abstract:LetX=l1+l2.D...  相似文献   

11.
侯吉成 《数学研究》2001,34(1):32-42
刻画了Fell-拓扑的某些性质以及Fell-拓扑和拓扑收敛的关系。  相似文献   

12.
Siberian Mathematical Journal - Let X be a Banach space and let T: X → X be a linear power bounded operator. Put X 0 = {x ∈ X | T n x → 0}. We prove that if X 0 ≠ X then...  相似文献   

13.
设X为一个集合,■_X为X上的全变换半群.设E是X上的一个等价关系,定义T_E(X)={f∈■_X:■(x,y)∈E,(f(x),f(y))∈E},则T_E(X)是由等价关系E所确定的■_X的子半群.本文中,所考虑的集合X是一个有限全序集,同时E是非平凡的且所有的E-类都是凸集.显然■_E(X)={f∈T_E(X):■_x,y∈X,x≤y蕴涵f(x)≤f(y)}是T_E(X)的一个子半群.我们赋予■_E(X)自然偏序并讨论何时■_E(X)中的两个元素是关于这个偏序是相关的,然后确定■_E(X)中那些关于≤是相容的元素.此外,还描述了极大(极小)元和覆盖元.  相似文献   

14.
设随机变量 X具有概率密度函数 f (x) ,X1,… ,Xn为 f (x)的样本 ,基于 X1,… ,Xn定义一类 f (x)的估计 fn(x) .本文在 X1,… ,Xn为 α——混合、ρ——混合样本时 ,得到了 fn(x)的渐近正态性  相似文献   

15.
在林寿与我最近合作的一篇文章中指出了∑*-空间的构成定理需重新考虑.本文就是要证明在空间X的每个点是Gδ-集的条件下该构成定理是成立的,所得的结论是:X是T1且每个点是Gδ-集的∑*-空间,如果f:X→Y是闭的满连续映射,则在Y中有一σ-闭离散子空间Z,使得对每个y∈Y\Z,f-1(y)是X的w1-紧子空间.为得到该主要结果,本文证明了若空间X是每个点是Gδ-集的次亚紧空间.则X中的每个闭离散子集是X中的Gδ-集.  相似文献   

16.
This paper characterizes ideal structure of the uniform Roe algebra B*(X) over simple cores X. A necessary and sufficient condition for a principal ideal of B*(X) to be spatial is given and an example of non-spatial ideal of B*(X) is constructed. By establishing an one-one correspondence between the ideals of B* (X) and the ω-filters on X, the maximal ideals of B*(X) are completely described by the corona of the Stone-Cech compactification of X.  相似文献   

17.
We prove that a locally compact ANR-space X is a Q-manifold if and only if it has the Disjoint Disk Property (DDP), all points of X are homological Z∞-points and X has the countable-dimensional approximation property (cd-AP), which means that each map f:K→X of a compact polyhedron can be approximated by a map with the countable-dimensional image. As an application we prove that a space X with DDP and cd-AP is a Q-manifold if some finite power of X is a Q-manifold. If some finite power of a space X with cd-AP is a Q-manifold, then X2 and X×[0,1] are Q-manifolds as well. We construct a countable familyχof spaces with DDP and cd-AP such that no space X∈χis homeomorphic to the Hilbert cube Q whereas the product X×Y of any different spaces X, Y∈χis homeomorphic to Q. We also show that no uncountable familyχwith such properties exists.  相似文献   

18.
Let L be a continuous semilattice. We use USC(X, L) to denote the family of all lower closed sets including X × {0} in the product space X × AL and ↓1 C(X,L) the one of the regions below of all continuous maps from X to AL. USC(X, L) with the Vietoris topology is a topological space and ↓C(X, L) is its subspace. It will be proved that, if X is an infinite locally connected compactum and AL is an AR, then USC(X, L) is homeomorphic to [-1,1]ω. Furthermore, if L is the product of countably many intervals, then ↓ C(X, L) is homotopy dense in USC(X,L), that is, there exists a homotopy h : USC(X,L) × [0,1] →USC(X,L) such that h0 = idUSC(X,L) and ht(USC(X,L)) C↓C(X,L) for any t > 0. But ↓C(X, L) is not completely metrizable.  相似文献   

19.
设x是简单无向图,G是Aut(X)的一个于群,X称为G-对称的,如果G在x的1-孤(即两相邻顶点构成的有序偶)集合上的作用是传递的;x称为对称图,如果X是Aut(x)-对称的;x称为可解对称的,如果Aut(X)包含可解子群G,使X是G-对称的.本文给出了具有6P个顶点的可解对称图的一个分类,这里p≥5是素数.  相似文献   

20.
Let Y be a subset of X and T(X, Y) the set of all functions from X into Y. Then, under the operation of composition, T(X, Y) is a subsemigroup of the full transformation semigroup T(X). Let E be an equivalence on X. Define a subsemigroup $$T_E(X,Y)$$ of T(X, Y) by $$\begin{aligned} T_E(X,Y)=\{\alpha \in T(X,Y):\forall (x,y)\in E, (x\alpha ,y\alpha )\in E\}. \end{aligned}$$Then $$T_E(X,Y)$$ is the semigroup of all continuous self-maps of the topological space X for which all E-classes form a basis carrying X into a subspace Y. In this paper, we give a necessary and sufficient condition for $$T_E(X,Y)$$ to be regular and characterize Green’s relations on $$T_E(X,Y)$$. Our work extends previous results found in the literature.  相似文献   

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