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On Inverse Limits and Direct Limits for Fuzzy Topological Spaces
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作者 A.Behera J.K.Sahu 《模糊系统与数学》 CSCD 北大核心 2010年第1期45-50,共6页
Li has introduced the concepts of inverse system and direct system for fuzzy topological spaces and studied inverse limits and direct limits on such spaces by presenting the explicit constructions of these limits.In t... Li has introduced the concepts of inverse system and direct system for fuzzy topological spaces and studied inverse limits and direct limits on such spaces by presenting the explicit constructions of these limits.In this paper some important concepts of fuzzy topology,such as,product fuzzy topology,quotient fuzzy topology,fuzzy continuity etc.,are used for further study of inverse limits and direct limits for fuzzy topological spaces. 展开更多
关键词 模糊拓扑 逆向极限 方向极限 代数
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ON CONDITIONS FOR THE NON LOCALLY CONVEX LINEAR TOPOLOGICAL SPACE TO HAVE THE H.-B. EXTENSION PROPERTY
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作者 SuLinning 《数学研究》 CSCD 1994年第1期158-162,共5页
ONCONDITIONSFORTHENONLOCALLYCONVEXLINEARTOPOLOGICALSPACETOHAVETHEH.-B.EXTENSIONPROPERTY¥SuLinning(Dept.ofMat... ONCONDITIONSFORTHENONLOCALLYCONVEXLINEARTOPOLOGICALSPACETOHAVETHEH.-B.EXTENSIONPROPERTY¥SuLinning(Dept.ofMath.,NingdeTeacher'... 展开更多
关键词 线性拓扑空间 线性连续函数 展开式性质 共轭独立
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General Topology of the Universe
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作者 Aalok Pandya 《Applied Mathematics》 2014年第16期2442-2446,共5页
General topology of the universe is described. It is concluded that topology of the present universe is greater or stronger than the topology of the universe in the past and topology of the future universe will be str... General topology of the universe is described. It is concluded that topology of the present universe is greater or stronger than the topology of the universe in the past and topology of the future universe will be stronger or greater than the present topology of the universe. Consequently, the universe remains unbounded. The general topological approach comprises of powerful techniques that could prove to be useful to prescribe mathematical constraints on the global character of the universe as well as on the manifold of space-time. 展开更多
关键词 General Topology MANIFOLD Boundary CAUSALITY Euclidean Space DISCRETENESS limit POINTS
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Space Topologies and Their Dual Space Topologies for Conventional Functional Space Topologies
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作者 Mahjoub A. Elamin 《Journal of Applied Mathematics and Physics》 2024年第3期778-804,共27页
In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topo... In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topological vector spaces and it is in this context that we have chosen to present this work. We are interested in the topology of its spaces and in the topologies of their dual spaces. The first part, we presented the fundamental topological properties of topological vector spaces. The second part, we studied Frechet spaces and particularly the space S(R<sup>n</sup>) of functions of class C<sup>∞ </sup>on R<sup>n</sup> which are as well as all their rapidly decreasing partial derivatives. We have also studied its dual S'(Rn</sup>) the space of tempered distributions. The last part aims to define a topological structure on an increasing union of Frechet spaces called inductive limit of Frechet spaces. We study in particular the space D(Ω) of functions of class C<sup>∞</sup> with compact supports on Ω as well as its dual D' (Ω) the space distributions over the open set Ω. 展开更多
关键词 linear Forms Dual spaces Frechet spaces Partial Derivatives DISTRIBUTIONS topological Structure Weak Topology Strong Topology
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On Linearly Topological Structure and Orthogonality of Menger Probabilistic Inner Product Spaces
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作者 肖建中 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2001年第3期355-361,共7页
In this paper the linearly topological structure of Menger Probabilistic inner product space is discussed. In virtue of these, some more general convergence theorems, Pythagorean theorem, and the orthogonal projective... In this paper the linearly topological structure of Menger Probabilistic inner product space is discussed. In virtue of these, some more general convergence theorems, Pythagorean theorem, and the orthogonal projective theorem are established. 展开更多
关键词 Propbabilistic inner product space linear topology CONVERGENCE orthogo- nal projection.
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Linear Dynamical System over Finite Distributive Lattice 被引量:1
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作者 DENG Aiping GONG Xiaoyue MA Hongcai 《Journal of Donghua University(English Edition)》 CAS 2021年第3期264-271,共8页
A finite dynamical system(FDS)over a lattice L is a pair(S(L),f),where S(L)is a left-L module and f is a mapping from S into itself.The phase space of(S(L),f)is a digraph whose vertex set is S(L)and there is an arc fr... A finite dynamical system(FDS)over a lattice L is a pair(S(L),f),where S(L)is a left-L module and f is a mapping from S into itself.The phase space of(S(L),f)is a digraph whose vertex set is S(L)and there is an arc from x to y if y=f(x).Let L be a finite distributive lattice,A an n×n matrix over L,and f(x)=Ax.The structure of the phase space of the FDS(Ln,f)is discussed.The number of limit cycles in the phase space of(Ln,f)is described in Möbius function.The phase spaces of some invertible,nilpotent,and idempotent FDS(Ln,f)are characterized explicitly. 展开更多
关键词 finite distributive lattice linear dynamical system phase space limit cycle rooted in-tree
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On Some Questions of Barge and Toledo 被引量:1
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作者 牛应轩 叶向东 《Northeastern Mathematical Journal》 CSCD 2000年第4期439-444,共6页
Barge asked if each homeomorphism of a hereditarily decomposable chainable continuum has zero topological entropy and Toledo asked if a homeomorphism of a chainable continuum can always be induced by square commuting ... Barge asked if each homeomorphism of a hereditarily decomposable chainable continuum has zero topological entropy and Toledo asked if a homeomorphism of a chainable continuum can always be induced by square commuting diagram on inverse systems of finite graphs. We show in this note that if Toledos question has a positive answer then Barges question also has a positive answer. 展开更多
关键词 topological entropy inverse limit space induced map and homeomorphism
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The Uniform Convergence Topology On Multi-valued Mapping Space
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作者 辛玉梅 谢鸿政 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第2期1-5,共5页
Some convergences of topology are discussed. The definitions of almost uniform convergence topology and compatible topology are given. It is shown that the quasiuniform convergence and generalized uniform convergence ... Some convergences of topology are discussed. The definitions of almost uniform convergence topology and compatible topology are given. It is shown that the quasiuniform convergence and generalized uniform convergence have no compatible topology,but the almost uniform convergence has compatible topology. Moreover, the description of all uniform convergence limits and their mutual relation are investigated[1]. 展开更多
关键词 ss: topological SPACE MULTI-VALUED mapping limit-cluster line
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Fuzzifying Topological Linear Spaces Based on Continuous-Valued logic 被引量:9
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作者 张广济 邹开其 张成 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2006年第1期77-88,共12页
In this paper, we introduce the concept of fuzzifying topological linear space and discuss the structures and properties of the balanced neighborhood system of zero element. We also give the algebraic properties and t... In this paper, we introduce the concept of fuzzifying topological linear space and discuss the structures and properties of the balanced neighborhood system of zero element. We also give the algebraic properties and the topological properties of fuzzifying convex set in the fuzzifying topological linear space. 展开更多
关键词 continuous-valued logic fuzzifying topological linear spaces balanced set zero element neighborhood system convex set.
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拓扑空间中的理想收敛
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作者 王武 张舜 《吉林大学学报(理学版)》 CAS 北大核心 2024年第1期13-19,共7页
用理想收敛结构解决定向拓扑的刻画问题,给出理想S极限和理想广义S极限可拓扑化的充要条件.结果表明:T0拓扑空间上的定向拓扑、理想S极限拓扑和理想广义S极限拓扑相同;定向空间中的理想S收敛是拓扑的当且仅当其为c-空间;定向空间中理想... 用理想收敛结构解决定向拓扑的刻画问题,给出理想S极限和理想广义S极限可拓扑化的充要条件.结果表明:T0拓扑空间上的定向拓扑、理想S极限拓扑和理想广义S极限拓扑相同;定向空间中的理想S收敛是拓扑的当且仅当其为c-空间;定向空间中理想广义S收敛是拓扑的当且仅当其为局部强紧空间. 展开更多
关键词 理想S极限 理想广义S极限 c-空间 局部强紧空间 定向拓扑
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拓扑空间中的理想下极限收敛
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作者 王武 张舜 《高校应用数学学报(A辑)》 北大核心 2024年第3期314-320,共7页
为了研究拓扑空间的收敛性质,引入了拓扑空间中网的理想下极限收敛和广义理想下极限收敛的概念,同时研究了这两类极限与C-空间和局部强紧空间之间的关系.特别的,借助交连续空间给出了C-空间的等价刻画.
关键词 拓扑空间 理想下极限 C-空间
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多工况下空间框架结构最小柔顺度拓扑优化
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作者 俞燎宏 曾文武 张水香 《宜春学院学报》 2024年第9期34-39,共6页
针对多工况作用下以柔顺度最小化为目标和体积为约束的空间框架结构拓扑优化问题,设计了一种新的优化思路。首先,利用Hypermesh软件和基结构法构建空间框架结构基础模型。其次,选用空心圆柱形梁单元,并以梁单元横截面外直径的平方为设... 针对多工况作用下以柔顺度最小化为目标和体积为约束的空间框架结构拓扑优化问题,设计了一种新的优化思路。首先,利用Hypermesh软件和基结构法构建空间框架结构基础模型。其次,选用空心圆柱形梁单元,并以梁单元横截面外直径的平方为设计变量;采用加权和方法处理多工况作用下的结构柔顺度,构建以体积为约束的拓扑优化初始模型,运用变体积约束限措施将初始模型进行等效近似转换。然后,对结构柔顺度和体积进行灵敏度分析,并采用移动渐近线法(MMA)进行优化求解。最后,通过两个优化算例验证了所提方法是正确可行且有效的,为空间框架结构的优化设计提供参考。 展开更多
关键词 空间框架结构 多工况 变体积约束限 结构柔顺度 拓扑优化
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Inverse limits in the category of locales 被引量:1
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作者 贺伟 刘应明 《Science China Mathematics》 SCIE 1998年第5期476-482,共7页
An explicit description of the construction of inverse limits of locales is given, and some properties of inverse limits of locales are shown by introducing a new type of limits\|collectionwise pullback. Specifically,... An explicit description of the construction of inverse limits of locales is given, and some properties of inverse limits of locales are shown by introducing a new type of limits\|collectionwise pullback. Specifically, a localic version of Steenrod theorem is proved without the axiom of choice and it is shown that an inverse limit of compact spatial loales is in general not spatial. As an application, the classic result by Steenrod is generalized. 展开更多
关键词 CATEGORY of locales inverse limit AXIOM of CHOICE CATEGORY of topological spaces.
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THE FUNCTIONAL DIMENSION OF SOME CLASSES OF SPACES
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作者 LIUSHANGPING LIBINGREN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2005年第1期67-74,共8页
The functional dimension of countable Hilbert spaces has been discussed by some authors. They showed that every countable Hilbert space with finite functional dimension is nuclear. In this paper the authors do further... The functional dimension of countable Hilbert spaces has been discussed by some authors. They showed that every countable Hilbert space with finite functional dimension is nuclear. In this paper the authors do further research on the functional dimension, and obtain the following results: (1) They construct a countable Hilbert space, which is nuclear, but its functional dimension is infinite. (2) The functional dimension of a Banach space is finite if and only if this space is finite dimensional. (3)Let B be a Banach space, B* be its dual, and denote the weak * topology of B* by σ(B*, B). Then the functional dimension of (B*, σ(B*, B)) is 1. By the third result, a class of topological linear spaces with finite functional dimension is presented. 展开更多
关键词 Functional dimension Countable Hilbert space topological linear space
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拓扑链遍历映射 被引量:3
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作者 孟鑫 关志强 刘国清 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2008年第3期475-477,共3页
通过引进链遍历的概念以及链遍历与拓扑遍历的关系,证明了拓扑遍历蕴涵链遍历但反之不然,指出对于满足伪轨跟踪性质的映射两种性质是等价的,并给出了动力系统序列与其生成的逆极限系统之间链遍历的相互蕴涵性,推广了拓扑遍历性已有的相... 通过引进链遍历的概念以及链遍历与拓扑遍历的关系,证明了拓扑遍历蕴涵链遍历但反之不然,指出对于满足伪轨跟踪性质的映射两种性质是等价的,并给出了动力系统序列与其生成的逆极限系统之间链遍历的相互蕴涵性,推广了拓扑遍历性已有的相应结果. 展开更多
关键词 链遍历 拓扑遍历 逆极限空间
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大口径深空探测天线的抗风干扰伺服系统 被引量:15
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作者 孙明玮 邱德敏 +1 位作者 王永坤 陈增强 《光学精密工程》 EI CAS CSCD 北大核心 2013年第6期1568-1575,共8页
为了改善风载荷干扰对深空探测天线跟踪精度和寿命的影响,设计了位置环线性自抗扰控制器。由于扰动观测器可以改善系统性能,本文基于电机动力学机理,将电流与速度的反馈与负载的影响作为总扰动的一部分,通过静态增益对前向通道的惯性环... 为了改善风载荷干扰对深空探测天线跟踪精度和寿命的影响,设计了位置环线性自抗扰控制器。由于扰动观测器可以改善系统性能,本文基于电机动力学机理,将电流与速度的反馈与负载的影响作为总扰动的一部分,通过静态增益对前向通道的惯性环节进行近似,极大地降低了扩张状态观测器的阶次;采用在线估计和补偿策略,抑制了风载荷干扰对控制系统的不利影响;利用描述函数法分析了包含摩擦特性的非线性系统闭环特性,说明这种控制策略可以避免极限环的产生。最后,开展了数学仿真和现场试验。在一深空探测系统上的应用结果显示,提出的控制策略超调比原产品减少了34%,抗击阵风干扰能力提高了60%,跟踪精度提高显著。得到的结果表明设计的控制策略提高了系统抗风干扰的能力。 展开更多
关键词 深空探测天线 线性自抗扰控制 扩张状态观测器 描述函数法 极限环 随机风干扰
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序列伪轨跟踪性与拓扑可迁 被引量:11
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作者 李明军 曾凡平 《广西大学学报(自然科学版)》 CAS CSCD 2000年第2期137-140,共4页
给出序列伪轨跟踪性的定义 ,得到拓扑可迁的一个充分条件 .并证明 ,若 f是同胚 ,则 f具有序列伪轨跟踪性当且仅当其逆极限空间上的移位映射σf
关键词 序列伪轨跟踪性 拓扑可迁 逆极限空间 动力系统
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关于线性空间的超平面 被引量:2
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作者 林鸿钊 张云南 《福建师范大学学报(自然科学版)》 CAS CSCD 2004年第2期8-14,共7页
主要讨论了超平面在线性空间、拓扑线性空间中的情形,阐述超平面在描写赋范线性空间中闭凸集的作用,并给出同构于其所有闭超平面的Banach空间的例子.
关键词 超平面 线性空间 拓扑线性空间 巴拿赫空间 H.I.空间
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半拓扑线性空间的子空间、乘积空间和商空间 被引量:2
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作者 吴大勇 康正华 苏雅拉图 《内蒙古师范大学学报(自然科学汉文版)》 CAS 2010年第4期346-350,共5页
在半拓扑线性空间的基础上,定义了半拓扑线性子空间、商半拓扑线性空间,讨论了它们的一些性质,给出在一定条件下乘积空间成为半拓扑线性空间的条件.
关键词 半开集 半拓扑线性空间 半拓扑线性子空间 乘积空间 商半拓扑线性空间
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拓扑空间上半连续函数的等价条件 被引量:2
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作者 卢天秀 朱培勇 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第5期50-53,共4页
首先给出了拓扑空间上网的上(下)极限和函数的上(下)极限的定义,以及一般拓扑空间到线性序拓扑空间的半连续函数的定义,然后得到了拓扑空间上函数连续和函数半连续的关系,最后证明了拓扑空间上函数半连续的几个等价条件.
关键词 半连续函数 上极限 下极限 线性序拓扑空间
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