期刊文献+
共找到541篇文章
< 1 2 28 >
每页显示 20 50 100
Brezis-Nirenberg Theorem on Non_compact Sets
1
作者 于淑兰 戚桂杰 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期49-52,共4页
In present paper we prove that on non_compact sets the conclusion in the Brezis_Nirenberg Theorem is also true.
关键词 critical value non compact sets pseudo_gradien t flow
下载PDF
RELATIVELY WEAKLY COMPACT SETS IN THE DENJOY SPACE
2
作者 Bongiorno Benedetto(Department of Mathematics, Via Archirafiy490123 Palermo ITALY) 《数学研究》 CSCD 1994年第1期37-44,共8页
RELATIVELYWEAKLYCOMPACTSETSINTHEDENJOYSPACE¥BongiornoBenedetto(DepartmentofMathematics,ViaArchirafiy490123Pa... RELATIVELYWEAKLYCOMPACTSETSINTHEDENJOYSPACE¥BongiornoBenedetto(DepartmentofMathematics,ViaArchirafiy490123PalermoITALY)Abstra... 展开更多
关键词 Denjoy空间 相关弱紧集 渐进等连续序列 亨斯托克积分函数
下载PDF
Weakly Compact Sets and Riesz Representation Theorem in Musielak Sequence Spaces
3
作者 Wan Zhong GONG Si Yu SHI Zhong Rui SHI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第2期467-484,共18页
In this work,we give some criteria of the weakly compact sets and a representation theorem of Riesz's type in Musielak sequence spaces using the ideas and techniques of sequence spaces and Musielak function.Finall... In this work,we give some criteria of the weakly compact sets and a representation theorem of Riesz's type in Musielak sequence spaces using the ideas and techniques of sequence spaces and Musielak function.Finally,as an immediate consequence of the criteria considered in this paper,the criteria of the weakly compact sets of Orlicz sequence spaces are deduced. 展开更多
关键词 compact set weak topology Banach space dual space Musielak sequence spaces
原文传递
Weakly Compact Sets and Orlicz Spaces
4
作者 石忠锐 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2001年第4期537-542,共6页
In this paper, We give the simple criteria of weakly compact sets in L1 and l1, which perfects Auto's result [1], Also as a corollary, we get Shur's theorem, In view of weak compactness, we give another pro... In this paper, We give the simple criteria of weakly compact sets in L1 and l1, which perfects Auto's result [1], Also as a corollary, we get Shur's theorem, In view of weak compactness, we give another proof of the reflexivity of Orlicz spaces, 展开更多
关键词 compact sets weak topology Orlicz space
下载PDF
Every Weakly Compact Set Can Be Uniformly Embedded into a Reflexive Banach Space 被引量:8
5
作者 Li Xin CHENG Qing Jin CHENG Zheng Hua LUO Wen ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2009年第7期1109-1112,共4页
Based on an application of the Davis-Figiel-Johnson-Pelzyski procedure, this note shows that every weakly compact subset of a Banach space can be uniformly embedded into a reflexive Banach space. As its application, w... Based on an application of the Davis-Figiel-Johnson-Pelzyski procedure, this note shows that every weakly compact subset of a Banach space can be uniformly embedded into a reflexive Banach space. As its application, we present the recent renorming theorems for reflexive spaces of Odell- Schlumprecht and Hajek-Johanis can be extended and localized to weakly compact convex subsets of an arbitrary Banach space. 展开更多
关键词 Banach space weakly compact set RENORMING
原文传递
Relatively Compact Sets on Abstract Wiener Space
6
作者 Xi Cheng ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2005年第4期819-822,共4页
In this note, we obtain a sufficient and necessary condition for a set in an abstract Winner space (X, H, μ) to be relatively compact in L^2(X, μ). Meanwhile, we give a sufficient condition for relative compactn... In this note, we obtain a sufficient and necessary condition for a set in an abstract Winner space (X, H, μ) to be relatively compact in L^2(X, μ). Meanwhile, we give a sufficient condition for relative compactness in L^P(X, μ) for p〉1. We also provide an example of Da Prato-Malliavin Nualart to show the result. 展开更多
关键词 Relatively compact sets Abstract Wiener space Malliavin calculus
原文传递
On the variational principle for the topological pressure for certain non-compact sets 被引量:2
7
作者 PEI Yu 1 & CHEN ErCai 1,2,1 Department of Mathematics,Nanjing Normal University,Nanjing 210097,China 2 Center for Nonlinear Science,Nanjing University,Nanjing 210093,China 《Science China Mathematics》 SCIE 2010年第4期1117-1128,共12页
Let (X,d,T) be a dynamical system,where (X,d) is a compact metric space and T:X → X is a continuous map.We assume that the dynamical system satisfies g-almost product property and the uniform separation property.We c... Let (X,d,T) be a dynamical system,where (X,d) is a compact metric space and T:X → X is a continuous map.We assume that the dynamical system satisfies g-almost product property and the uniform separation property.We compute the topological pressure of saturated sets under these two conditions.If the uniform separation property does not hold,we compute the topological pressure of the set of generic points.We give an application of these results to multifractal analysis and finally get a conditional variational principle. 展开更多
关键词 uniform separation PROPERTY g-almost product PROPERTY topological pressure of non-compact sets VARIATIONAL principle BS-dinmension
原文传递
Fixed Point Theorems for Increasing Operators of None-continuity and None-compactness Conditions
8
作者 张庆政 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第4期54-56, ,共3页
In this paper, the fixed point theorems of composite set-valued increasing operators are given. As a corollary, the fixed point theorem for increasing operator of none-continuity and nonecompactness conditions is also... In this paper, the fixed point theorems of composite set-valued increasing operators are given. As a corollary, the fixed point theorem for increasing operator of none-continuity and nonecompactness conditions is also given. Some relevant results are improved and generalized. 展开更多
关键词 semiordered topological spaces upper half-closed set relative compact set set-valuedincreasing operators fixed point
下载PDF
基于Level Set方法的人脸轮廓提取
9
作者 柳长青 田振夫 《计算机工程与设计》 CSCD 北大核心 2008年第12期3179-3181,3184,共4页
人脸轮廓提取在诸如安全检查、保安管理、交通电子监控、机器人研究等方面有着十分重要的应用价值。先利用图像背景差分法快速检测出人脸的初始矩形轮廓线,然后采用LevelSet方法对视频图像进行人脸轮廓提取,Level Set演化函数空间方向... 人脸轮廓提取在诸如安全检查、保安管理、交通电子监控、机器人研究等方面有着十分重要的应用价值。先利用图像背景差分法快速检测出人脸的初始矩形轮廓线,然后采用LevelSet方法对视频图像进行人脸轮廓提取,Level Set演化函数空间方向上采用四阶紧致差分逼近式离散,计算过程中加入了窄带算法和全局优化方法。数值实验结果表明,该算法在不增加计算时间的基础上,可以检测出模糊或离散的边界,并得到精确的人脸轮廓线。 展开更多
关键词 Levelset方法 轮廓提取 紧致差分 计算机视觉 图像处理
下载PDF
A Characteristic of Cantor Sets 被引量:1
10
作者 麦结华 《柳州师专学报》 2013年第1期108-110,共3页
It is well known that a totally disconnected compact metric space without isolated points is a Cantor set.In this note me give a simple proof of this theorem.
关键词 摘要 编辑部 编辑工作 读者
下载PDF
基于Level Set方法的西夏字轮廓提取 被引量:2
11
作者 柳长青 《中文信息学报》 CSCD 北大核心 2009年第4期71-76,共6页
随着国内外对西夏研究的不断深入,收藏于世界各地的大批西夏古籍文献通过影印方式陆续出版。如何将这些西夏古籍文献进行数字化、文本化则有着极其重要的意义。首先利用平滑和细化算法对西夏影印文献进行了预处理,然后利用Level set方... 随着国内外对西夏研究的不断深入,收藏于世界各地的大批西夏古籍文献通过影印方式陆续出版。如何将这些西夏古籍文献进行数字化、文本化则有着极其重要的意义。首先利用平滑和细化算法对西夏影印文献进行了预处理,然后利用Level set方法对影印文献中的西夏字进行了轮廓提取。Level Set演化函数在空间方向上采用了四阶紧致差分逼近式离散,计算过程中加入了窄带算法及全局优化方法。实验表明,算法在不增加计算时间的基础上可以得到较精确的西夏字轮廓。 展开更多
关键词 人工智能 模式识别 西夏文信息处理 LEVEL set方法 西夏字 轮廓提取 紧致差分
下载PDF
Degree of Compactness in I-fuzzy Topological Spaces 被引量:1
12
作者 李宏艳 《Northeastern Mathematical Journal》 CSCD 2008年第6期485-491,共7页
In this paper, the concept of degree of compactness is introduced in the general framework of I-fuzzy topological spaces, and its property is discussed. All good compactness are generalized to I-fuzzy topological spac... In this paper, the concept of degree of compactness is introduced in the general framework of I-fuzzy topological spaces, and its property is discussed. All good compactness are generalized to I-fuzzy topological spaces accordingly. 展开更多
关键词 I-fuzzy topology value set of compactness degrees of compactness
下载PDF
函数空间C_k(X)上的T-Tightness和Set-Tightness
13
作者 杨春梅 李祖泉 《杭州师范大学学报(自然科学版)》 CAS 2011年第2期124-126,132,共4页
讨论了函数空间Ck(X)在赋予紧开拓扑下的T-tightness和set-tightness性质,利用开k覆盖获得了Ck(X)是T-tightness空间和set-tightness空间的两个对偶定理,将点态收敛拓扑函数空间Cp(X)的相关结论推广到紧开拓扑函数空间Ck(X)上.
关键词 函数空间 紧开拓扑 T—tightness set—tightness k覆盖
下载PDF
A NOTE IN APPROXIMATIVE COMPACTNESS AND MIDPOINT LOCALLY K-UNIFORM ROTUNDITY IN BANACH SPACES 被引量:4
14
作者 刘春燕 张子厚 周宇 《Acta Mathematica Scientia》 SCIE CSCD 2018年第2期643-650,共8页
In this article, we prove the following results: (1) A Banach space X is weak midpoint locally k-uniformly rotund if and only if every closed ball of X is an approximatively weakly compact k-Chebyshev set; (2) A ... In this article, we prove the following results: (1) A Banach space X is weak midpoint locally k-uniformly rotund if and only if every closed ball of X is an approximatively weakly compact k-Chebyshev set; (2) A Banach space X is midpoint locally k-uniformly rotund if and only if every closed ball of X is an approximatively compact k-Chebyshev set. 展开更多
关键词 k-Chebyshev set approximatively weak compactness approximative compactness weak midpoint locally k-uniform rotundity midpoint locally k-uniform rotundity k-strict rotundity
下载PDF
Distributed Nash Equilibrium Seeking on Compact Action Sets over Jointly Strongly Connected Switching Networks
15
作者 HE Xiongnan HUANG Jie 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2024年第1期63-81,共19页
This paper studies the distributed Nash equilibrium seeking(DNES)problem for games whose action sets are compact and whose network graph is switching satisfying the jointly strongly connected condition.To keep the act... This paper studies the distributed Nash equilibrium seeking(DNES)problem for games whose action sets are compact and whose network graph is switching satisfying the jointly strongly connected condition.To keep the actions of all players in their action sets all the time,one has to resort to the projected gradient-based method.Under the assumption that the unique Nash equilibrium is the unique equilibrium of the pseudogradient system,an algorithm is proposed that is able to exponentially find the Nash equilibrium.Further,the authors also consider the distributed Nash equilibrium seeking problem for games whose actions are governed by high-order integrator dynamics and belong to some compact sets.Two examples are used to illustrate the proposed approach. 展开更多
关键词 compact action sets jointly strongly connected switching graphs Nash equilibrium seeking projected gradient-based algorithm.
原文传递
一类不连续系统的解集的性质
16
作者 马学敏 《甘肃高师学报》 2024年第2期7-11,共5页
利用比Lebesgue积分更为广泛的Henstock-Kurzweil积分,得出一类不连续系统的解集在Banach空间中是紧且连通的.
关键词 不连续系统 Henstock-Kurzweil积分 解集 紧且连通性
下载PDF
τ-CHEBYSHEV AND τ-COCHEBYSHEV SUBPSACES OF BANACH SPACES
17
作者 H.Mazaheri 《Analysis in Theory and Applications》 2006年第2期141-145,共5页
The concepts of quasi-Chebyshev and weakly-Chebyshev and σ-Chebyshev were defined [3 - 7], andas a counterpart to best approximation in normed linear spaces, best coapprozimation was introduced by Franchetti and Furi... The concepts of quasi-Chebyshev and weakly-Chebyshev and σ-Chebyshev were defined [3 - 7], andas a counterpart to best approximation in normed linear spaces, best coapprozimation was introduced by Franchetti and Furi^[1]. In this research, we shall define τ-Chebyshev subspaces and τ-cochebyshev subspaces of a Banach space, in which the property τ is compact or weakly-compact, respectively. A set of necessary and sufficient theorems under which a subspace is τ-Chebyshev is defined. 展开更多
关键词 best approximation best coapproximation τ-Chebyshev subspace τ-cochebyshev subspace compact set weakly compact set
下载PDF
L-拓扑空间中的p-良紧性 被引量:9
18
作者 马保国 王延军 姜金平 《重庆师范大学学报(自然科学版)》 CAS 2006年第4期10-14,共5页
首先讨论了L-拓扑空间中的预开集、预半开集等概念,然后利用这些概念在L-拓扑空间中提出了p-(ps-)良紧集的概念,研究了它们的基本特征,讨论了它们的一些基本性质。
关键词 L-拓扑空间 预开集 预半开集 p-(ps-)良紧集 α-p(α-ps)远域族
下载PDF
LF闭包空间的层紧性 被引量:6
19
作者 尤飞 李洪兴 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2003年第3期316-319,共4页
在LF闭包空间中 ,引入层紧集概念 ,进一步 ,定义了层紧空间概念 .并用α渗透 ,M可达的等概念刻画了层紧集的性质 .给出了层紧集的几个等价刻画 .
关键词 LF闭包空间 层紧性 层紧集 层紧空间 a-渗透 M-可达 弱同胚不变性质 弱拓扑不变性质
下载PDF
LF闭包空间的紧性 被引量:10
20
作者 尤飞 李洪兴 《内蒙古大学学报(自然科学版)》 CAS CSCD 北大核心 2003年第2期142-145,共4页
在LF闭包空间中,引入包域、α-包域族等概念并以这些概念为基础定义了紧集和紧空间的概念.给出了紧集的等价刻画;证明了承载集有限的集是紧集;紧性是弱同胚不变性质等.特别是定义了分明闭包空间的紧性,并证明了这样定义的紧性是L-好的推广.
关键词 LF闭包空间 包域 紧集 L-好的推广
下载PDF
上一页 1 2 28 下一页 到第
使用帮助 返回顶部