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1.
Assume X is a normed space,every x * ∈ S(X*) can reach its norm at some point in B(X),and Y is a β-normed space.If there is a quotient space of Y which is asymptotically isometric to l β,then L(X,Y) contains an asymptotically isometric copy of l β.Some sufficient conditions are given under which L(X,Y) fails to have the fixed point property for nonexpansive mappings on closed bounded β-convex subsets of L(X,Y).  相似文献   

2.
In this note we study the property(ω1),a variant of Weyl's theorem by means of the single valued extension property,and establish for a bounded linear operator defined on a Banach space the necessary and sufficient condition for which property(ω1) holds.As a consequence of the main result,the stability of property(ω1) is discussed.  相似文献   

3.
岳修奎 《数学季刊》2012,(3):344-351
In this paper, we give some new results of the coefficient multiplier of some analytic function spaces, characterize the coefficient multiplier spaces (Hα, p Hβ q) and (Ap,α), Aq,β) with 0 < p ≤ 1, p ≤ q ≤∞, 0 ≤α < β < ∞ and show (Hα∞, Hβ∞) = Hβ-α1 with 0 < α < β < ∞.  相似文献   

4.
主要讨论性质 ( u)从 Banach空间 Xn 到 PXXn 的提升问题 ,它是 lp( Xn)中相应结果的推广 .  相似文献   

5.
In this note we define the property (ω′), a variant of Weyl’s theorem, and establish for a bounded linear operator defined on a Hilbert space the necessary and sufficient conditions for which property (ω′) holds by means of the variant of the essential approximate point spectrum σ1(·) and the spectrum defined in view of the property of consistency in Fredholm and index. In addition, the perturbation of property (ω′) is discussed.  相似文献   

6.
In this note we study the property (ω), a variant of Weyl's theorem introduced by Rakocevic, by means of the new spectrum. We establish for a bounded linear operator defined on a Banach space a necessary and sufficient condition for which both property (ω) and approximate Weyl's theorem hold. As a consequence of the main result, we study the property (ω) and approximate Weyl's theorem for a class of operators which we call the λ-weak-H(p) operators.  相似文献   

7.
In this paper, a new Ky Fan matching theorem is established in noncompact L-convex spaces. As applications, a fixed point theorem and equilibrium existence theorems for systems of general quasiequilibrium problems and systems of quasiequilibrium problems in noncompact L-convex spaces are obtained.  相似文献   

8.
本文系统的给出余弦算子函数的共轭性理论,并引入了余弦函数的θ-自反概念,及给出了一些基本特征  相似文献   

9.
In this paper,we obtain the characterizations on μ for(p,q)-φCarleson measure,and discuss the boundedness(and compactness) of the extended Cesaro operators T g between different weighted Bergman spaces as some application.  相似文献   

10.
(1)X是W-Like空间,则bX是Lindel?f空间;(2)若X,n∈N是W-Like空间,则∏n∈N是Lindel?f空间.  相似文献   

11.
证明了在某种紧性条件下拟桶式空间的强对偶空间值的向量测度的唯一存在性。  相似文献   

12.
主要给出下面结果.即PzXn。具有滴性和弱滴性的充分必要条件是每个Xn具有滴性和弱滴性条件.  相似文献   

13.
无限直和的一些性质   总被引:2,自引:0,他引:2  
王建华 《东北数学》2005,21(3):345-354
In this paper, we study the sequential convergence in .E-direct sums E(X) where X is an Ω-family of Banach spaces and discuss the lifting of the Kadec-Klee property from X to E(X).  相似文献   

14.
Throughout this paper R denotes the set of all real numbers.An extended real valued function j f X-[--oo, +oc] is called lower semicontinuouson X if fOr each real Q, {x' f(x) > o} is open in X. Clearly, f is lower semicontinuous ifand only if, its epigraph eghf = {(x, a) f f(x) 5 cr} is closed in X x R. f is caJ1ed proper ifit is somewhere finite, and its values lie in (--co, +oc]. We denote by LSC(X) the set of ajlproper lower semicontinuous functions.In the sequel, we identify lower se…  相似文献   

15.
张子厚  刘瑞娟 《数学研究》2005,38(3):292-297
证明了(C-K)性质,(S-K)性质,L-KR空间,L-KS空间和CL-KR空间和CL-KS空间的一些充要条件.这些条件表明了(C-K)与(S-K)性质,L-KR与L-KS空间及CL-KR空间与CL-KS空间之间的对偶性质.  相似文献   

16.
本文讨论了选取不同类型权重序列$\{w(t)\}_{t\in \mathbb{Z}}$时,权重$l_2(\mathbb{Z},w)$空间上关联线性时不变算子的性质,同时还讨论了非稳定关联线性时不变卷积算子的可闭性的有关问题,提出了关于线性时不变算子一些新的问题,并指出可在一大类权重$l_2(\mathbb{Z},w)$空间上进行鲁棒设计.  相似文献   

17.
The James-Schreier spaces Vp, where 1?p<∞, were recently introduced by Bird and Laustsen (in press) [5] as an amalgamation of James' quasi-reflexive Banach space on the one hand and Schreier's Banach space giving a counterexample to the Banach-Saks property on the other. The purpose of this note is to answer some questions left open in Bird and Laustsen (in press) [5]. Specifically, we prove that (i) the standard Schauder basis for the first James-Schreier space V1 is shrinking, and (ii) any two Schreier or James-Schreier spaces with distinct indices are non-isomorphic. The former of these results implies that V1 does not have Pe?czyński's property (u) and hence does not embed in any Banach space with an unconditional Schauder basis.  相似文献   

18.
Let $A$ be a general expansive matrix on $\mathbb{R}^n$. The aims of this article are twofold. The first one is to give a survey on the recent developments of anisotropic Hardy-type function spaces on $\mathbb{R}^n$, including anisotropic Hardy–Lorentz spaces, anisotropic variable Hardy spaces and anisotropic variable Hardy–Lorentz spaces as well as anisotropic Musielak–Orlicz Hardy spaces. The second one is to correct some errors and seal some gaps existing in the known articles. Some unsolved problems are also presented.  相似文献   

19.
可数基的Banach空间上的向量值函数的一些性质   总被引:1,自引:0,他引:1  
用初等的方法讨论了取值于具有可数基的Banach空间上的向量值函数的连续、可导、解析、可积及解析的充要条件等性质,得出取值于可数基的Banach空间上的向量值函数解析的两个充要条件.  相似文献   

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