hit-or-miss拓扑上的度量:直接扩充

设E是Hausdorff局部紧第二可数拓扑空间.用F表示由E的所有闭子集构成的超空间,其上赋予hit-or-miss拓扑.本文引入了E上的紧型度量和F上保距扩张的概念,建立了E上度量是紧型的充分必要条件,并且证明了E上任何一个紧型度量度可以直接扩充为F上的保距度量.     

超空间上的连续对应与对应的闭图

本文的目的是在超空间上重新定义上半连续,下半连续和连续对应.改进了Klein在［1］中的定义7.1.1,得到了这些对应和它们的闭图的若干特征和性质,给出了子集网在下半连续对应中的应用.     

拓扑空间子集的最小开集和最大闭集

讨论对于拓扑空间子集A是否存在包含A的最小开集和是否存在包含于A的最大闭集问题,证明了拓扑空间X是一个T1空间之充分且必要条件是,对于X的每一个子集A,X中存在包含A的最小开集（存在包含于A的最大闭集）当且仅当A是X的开集（闭集）,同时给出几个例子说明了定理的条件.     

超空间上的连续对应与对应的闭图

本文的目的是在超空间上重新定义上半连续,下半连续和连续对应．改进了Ｋｌｅｉｎ在［１］中的定义７．１．１,得到了这些对应和它们的闭图的若干特征和性质,给出了子集网在下半连续对应中的应用     

L—fuzzy拓扑空间中近良紧集的刻画

本文在Ｌ－ｆｕｚｚｙ拓扑空间中，针对Ｌ－ｆｕｚｚｙ子集定义子Ｍｒ－复盖及具有有限Ｍｒ交性质的闭集族等概念，并以此刻画了近良紧集的一组特性，证明了近良紧的对正则闭集遗传以及是“Ｌ－ｇｏｏｄ ｅｘｔｅｎｓｉｏｎ”等结论。     

Fell-拓扑的伪紧性（英文）

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。     

L－fuzzy拓扑空间中近良紧集的刻画

本文在Ｌ－ｆｕｚｚｙ拓扑空间中，针对Ｌ－ｆｕｚｚｙ子集定义了Ｍｒ－复盖及具有有限Ｍｒ－交性质的闭集族等概念，并以此刻画了近良紧集的一组特征，证明了近良紧性对正则闭集遗传以及是“Ｌ－ｇｏｏｄｅｘｔｅｎｓｉｏｎ”等结论。     

局部有限超拓扑的局部紧性

本文讨论了赋予局部有限拓扑的非空闲子集超空间的局部紧性.主要结果是:X正则,则其闭子集超空间局部紧当且仅当X可表示成一个紧空间与一个离散空间的拓扑和.     

关于局部紧空间的闭Lindelof映象

本文给出了两类局部紧空间闭Ｌ（Ｌｉｎｄｅｌｏｆ）映象的内部特征,证明了空间Ｘ是仿紧局部紧空间的闭Ｌ映象当且发Ｘ是具有σ－局部有限ｋ系的ｋ空间,由此得到在ｋ′空间类中,偏紧局部紧空间的闭Ｌ映象等价于偏紧局部紧空间的商ＳＬＪ央象,同时不证明了空间Ｘ是局部紧度量空间的闭Ｌ映象当且Ｘ是具有σ－局部有限紧ｋ网的Ｆｒｅｃｈｅｔ空间。     

点是Gδ-集的∑*-空间的构成定理

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.     

COMPACT COMPOSITION OPERATORS ON GENERALIZED LIPSCHITZ SPACES

In this paper, boundedness and compactness of the composition operator on the generalized Lipschitz spaces Λα (α > 1) of holomorphic functions in the unit disk are characterized.     

Bloch空间上紧的乘积算子

本文研究了Bloch函数空间上紧乘积算子，引入了消失α-Caleson测度，利用它给出Bloch空间和小Bloch空间上的乘积算子Mφf=φf紧性的一个充分条件。     

COMPACT COMPOSITION OPERATORS ON WEIGHTED BERGMAN SPACES ON BOUNDED SYMMETRIC DOMAINS

In this article, we borrow the idea of using Schur’s test to characterize the compactness of composition operators on the weighted Bergman spaces in a bounded symmetric domain Ω, and verify that Cφ is compact on L q a (Ω, dv β ) if and only if K ( φ ( z ) ,φ ( z )) K ( z,z ) → 0 as z →φΩ under a mild condition, where K(z, w) is the Bergman kernel.     

INEQUALITY OF KORN‘S TYPE ON COMPACT SURFACES WITHOUT BOUNDARY

Inequalities of Korn's type on a surface with boundary have been proved in many papers using different techniques (see e.g. [4, 5, 11]). The author proves here an inequality of Korn's type on a compact surface without boundary. The idea is to use a finite number of maps for defining the surface and the inequality of Korn's type without boundary conditions for every map and to recast these in a general functional analysis setting about quotient spaces.     

STABILITY OF SOME POSITIVE LINEAR OPERATORS ON COMPACT DISK

Recently,Popa and Rasa[27,28]have shown the(in)stability of some classical operators defined on[0,1]and found best constant when the positive linear operators are stable in the sense of Hyers-Ulam.In this paper we show Hyers-Ulam(in)stability of complex Bernstein-Schurer operators,complex Kantrovich-Schurer operators and Lorentz operators on compact disk.In the case when the operator is stable in the sense of Hyers and Ulam,we find the infimum of Hyers-Ulam stability constants for respective operators.     

NOTE ON SOME CHARACTERISATIONS OF UNBOUNDED WEAKLY COMPACT OPERATORS

Abstract

Some well known properties of bounded weakly compact operators in Banach spaces are shown to be valid for arbitrary operators in normed spaces.     

AN EIGENSPACE CHARACTERIZATION OF LORENTZ-IMPROVING MEASURES ON COMPACT GROUPS

Abstract

A measure μ on a compact group is called Lorentz-improving if for some 1 > p > ∞ and 1 → q ₁ > q ₂ ∞ μ *L (p, q ₂) ? L(p, q ₁). Let T _μ denote the operator on L ² defined by T _μ(f) = μ * f. Lorentz-improving measures are characterized in terms of the eigenspaces of T _μ, if T _μ is a normal operator, and in terms of the eigenspaces of |T _μ| otherwise. This result generalizes our recent characterization of Lorentz-improving measures on compact abelian groups and is modelled after Hare's characterization of L ^p -improving measures on compact groups.     

HYPOELLIPTICITY OF NONSINGULAR CLOSED 1-FORMS ON COMPACT MANIFOLDS

ABSTRACT

Hypoellipticity of nonsingular closed 1-forms on compact manifolds is characterized by a diophantine condition on the generators of the group of periods of the form.     

加权Bergman空间上的Toeplitz算子和Hankel算子

西方给出了Ｃ＾ｎ中单位球上的带权的Ｂｅｒｇｍａｎ空间上具一般符号的Ｔｏｅｐｌｉｔｚ算子和Ｈａｎｋｅｌ算子为紧的充要条件。     

THE SPECTRUM OF THE LAPLACE OPERATION ON COMPACT SUBMANIFOLDS

1IntroductionLetiM.g)beac0mpactn-dimensi0nd1Riemannianmanffold.ByAwedenotetheLaplacianartingonpf0rnaonM.Thenwehavethespectrumforeachp:Oneoftlieprob1emonspectraisasf0110ws:Let(M,g)and(M,g)becompactoritabieRicmannianmanif01dswithSpecp(M.g)=Specp{M-g),thenis(M,g)isometricto(M-j)?Thisprob1emisprovedtobewrongbyJ.Milnorin1964.Butwhen(M,g)and(M.g)aresonlespecialffiemannianmanifolds.undercertainconditi0ns.wecanprovethat(M.g)'sisometricto{M.j).Foran-din1ensi0nsubmanitbldMinSN,wedenotetheleng…