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1.
王漱石 《数学研究》2000,33(2):128-134
设Γ为非空集,X为实Banach空间,本研究赋Day范数的c0(Γ,X)的光滑点,强光滑点,暴露点和强暴露点。  相似文献   

2.
本文给出l∞(X)以及L1(l1(X),y),L(X,l∞(Y))和L(X,co(Y))的单位球的有限阶光滑点和强光滑点的充要条件,这是X和Y都是任意的Banach空间,特别地,本文给出这些空间的单位球的光滑点和强光滑点的充要条件。  相似文献   

3.
局部k-一致凸空间的对偶空间   总被引:3,自引:0,他引:3  
本文证明了若Banach空间X是局部k-一致凸的,则对每个x∈S(X),f∈Σ(x)是X*的k-强光滑点,并得到局部k-一致凸空间的几个性质.  相似文献   

4.
本文研究了Banach空间的弱序列紧性.Banach空间X称为有(w)性质,如果X(X的共轭空间)的每个有界序列有弱收敛子列.我们证明了,如果Banach空间X有(w)性质,那么lp(X)(1≤p<+∞)与c0(X)也有(w)性质.  相似文献   

5.
本文引入了Banacj空间X的弱局部Z性质和弱Z性质,得出了:Banach空间X是K-NUC空间的一个充分必要条件和Banach空间X是LK-NUC空间的一个充分条件,并指出弱Z性质蕴含弱Banach-Saks性质.  相似文献   

6.
南朝勋 《数学研究》1994,27(2):82-86
本文讨论强凸性、L-kR,LωR和(G)性质之间的关系,指出强凸性介于LωR和(G)性质之间,证明光滑的有(G)性质的Banach空间是强凸的,此外指出存在一个Banach空间X,它是LωR但对任意自然数k,X不是L-kR.  相似文献   

7.
Banach空间的型与独立Banach空间值随机变量序列的不等式   总被引:3,自引:0,他引:3  
甘师信 《数学学报》1995,38(6):752-758
本文建立了独立B值随机变量序列部分和的极大值函数S*与p方根函数S(p,X)的分布函数不等式与矩不等式,讨论了这些不等式的成立与Banach空间的p型与q余型的关系,同时给出了与Hilbert空间同构的Banach空间的特征。  相似文献   

8.
本文主要研究了Banach空间(1≤p<∞)及其对偶空间的若干结构性质(这里X0是Banach空间X的闭子空间),得到了一些较有意义的结果.  相似文献   

9.
本文引入了Banacj空间X的弱局部Zk性质和弱Zk性质,得出了:Banach空间X是K-NUC空间的一个充分必要条件和Banach空间X是LK-NUC空间的一个充分条件,并指出弱Zk性质蕴含弱Banach-Saks性质.  相似文献   

10.
南朝勋 《数学杂志》1994,14(4):468-474
本文证明渐近赋范性质与(s)性质具有对偶性,并且给出一个Banach空间为HahnBanach光滑的充要条件。  相似文献   

11.
作者给出赋Luxemburg范数Musielak-Orlicz序列空间光滑点的支撑泛函的刻画.进一步,给出赋Orliez范数和赋Luxemburg范数Musielak-Orlicz序列空间的粗性,点态粗的充分必要条件.  相似文献   

12.
《Mathematische Nachrichten》2017,290(11-12):1678-1688
We investigate sufficient and necessary conditions for the space of bounded linear operators between two Banach spaces to be rough or average rough. Our main result is that is δ‐average rough whenever is δ‐average rough and Y is alternatively octahedral. This allows us to give a unified improvement of two theorems by Becerra Guerrero, López‐Pérez, and Rueda Zoca [J. Math. Anal. Appl. 427 (2015)].  相似文献   

13.
Axiomatics for fuzzy rough sets   总被引:42,自引:0,他引:42  
A fuzzy T-rough set consists of a set X and a T-similarity relation R on X, where T is a lower semi-continuous triangular norm. We generalize the Farinas-Prade definition for the upper approximation operator of a fuzzy T-rough set (X, R); given originally for the special case T = Min, to the case of arbitrary T. We propose a new definition for the lower approximation operator of (X,R). Our definition satisfies the two important identities and , as well as a number of other interesting properties. We provide axiomatics to fully characterize those upper and lower approximations.  相似文献   

14.
对于(p,q)算子范数,我们考虑由Goldberg定义的常数c(称为Goldberg常数)的确定问题.该问题(即求常数c的精确值或它的一个可以达到的最小上界问题)由Moshe Goldberg于1986年提出,且至今仍未能彻底解决.本文给出了常数c的一个上界,改进了Goldberg在1986年所得出的结果.  相似文献   

15.
讨论了四元数中的真半范数,并给出了它的一般形式,它适合核维数分别为1,2,3的情形,推广了复数域中的真半范数的一般形式,给出了一个较好的结果.  相似文献   

16.
《Optimization》2012,61(5):603-611
Classical mathematics is usually crisp while most real-life problems are not; therefore, classical mathematics is usually not suitable for dealing with real-life problems. In this article, we present a systematic and focused study of the application of rough sets (Z. Pawlak, Rough sets, In. J. Comput. Informa. Sci. 11 (1982), pp. 341–356.) to a basic area of decision theory, namely ‘mathematical programming’. This new framework concerns mathematical programming in a rough environment and is called ‘rough programming’ (L. Baoding, Theory and Practice of Uncertain Programming, 1st ed., Physica-Verlag, Heidelberg, 2002; E.A. Youness, Characterizing solutions of rough programming problems, Eut. J. Oper. Res. 168 (2006), pp. 1019–1029). It implies the existence of the roughness in any part of the problem as a result of the leakage, uncertainty and vagueness in the available information. We classify rough programming problems into three classes according to the place of the roughness. In rough programming, wherever roughness exists, new concepts like rough feasibility and rough optimality come to the front of our interest. The study of convexity for rough programming problems plays a key role in understanding global optimality in a rough environment. For this, a theoretical framework of convexity in rough programming and conceptualization of the solution is created on the lines of their crisp counterparts.  相似文献   

17.
We prove that any composition operator with maximal norm on one of the weighted Bergman spaces (in particular, on the space ) is induced by a disk automorphism or a map that fixes the origin. This result demonstrates a major difference between the weighted Bergman spaces and the Hardy space , where every inner function induces a composition operator with maximal norm.

  相似文献   


18.
1 引言 [1]中,讨论了C~(m×n)上的矩阵A的L_p范数/A/_p=(∑/a_(ij)/~p)和l_p算子范数‖A‖_p= max/AX/_p1』之间的关系,得到了下面的不等式: ‖A‖_p≤μ_p(n)/A/_p, ‖A‖_p≤μ_q(m)/A/_p, (1.1) 这里  相似文献   

19.
令 L~(p(x))(Ω)为变指数 Lebesgue空间,其中 p:Ω→[1,∞].‖·‖_(p(x))和‖·‖_(p(x))~o 分别表示 L~(p(x))(Ω)中的 Luxemburg 范数和共轭 Orlicz 范数.本文证明成立最佳不等式‖·‖_(p(x))≤‖·‖_(p(x))~o ≤ d_(p-,p )‖·‖_(p(x)),其中 d_(p-,p )是一个依赖于 p-=essinf_Ωp(x)和 p =esssup_Ωp(x)的常数.当1<p-<p <∞时, (?) 当 p-=1或 p =∞时,d(p-,p )是相应的极限形式.  相似文献   

20.
Abstract

In various normed spaces we answer the question of when a given isometry is a square of some isometry. In particular, we consider (real and complex) matrix spaces equipped with unitarily invariant norms and unitary congruence invariant norms, as well as some infinite dimensional spaces illustrating the difference between finite and infinite dimensions.  相似文献   

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