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On the Decomposition of a Bounded Closed Interval of the Real Line into Closed Sets
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作者 Edgar A. Cohen 《Advances in Pure Mathematics》 2013年第4期405-408,共4页
It has been shown by Sierpinski that a compact, Hausdorff, connected topological space (otherwise known as a continuum) cannot be decomposed into either a finite number of two or more disjoint, nonempty, closed sets o... It has been shown by Sierpinski that a compact, Hausdorff, connected topological space (otherwise known as a continuum) cannot be decomposed into either a finite number of two or more disjoint, nonempty, closed sets or a countably infinite family of such sets. In particular, for a closed interval of the real line endowed with the usual topology, we see that we cannot partition it into a countably infinite number of disjoint, nonempty closed sets. On the positive side, however, one can certainly express such an interval as a union of c disjoint closed sets, where c is the cardinality of the real line. For example, a closed interval is surely the union of its points, each set consisting of a single point being closed. Surprisingly enough, except for a set of Lebesgue measure 0, these closed sets can be chosen to be perfect sets, i.e., closed sets every point of which is an accumulation point. They even turn out to be nowhere dense (containing no intervals). Such nowhere dense, perfect sets are sometimes called Cantor sets. 展开更多
关键词 CANTOR sets CARDINALITY DISJOINT closed sets DYADIC Representation INTERLACING DYADIC Expansions Generators of sets Nowhere Dense
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Remarks on (1, 2)^*-Generalized Closed Sets with Respect to an Ideal Bitopological Space
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作者 H. S. Al-Saadi Takashi Noiri 《Journal of Mathematics and System Science》 2012年第6期348-351,共4页
In this paper, the authors introduce and study the concept of (1, 2)^*-generalized closed sets with respect to an ideal in a bitopological space. Also, some characterizations and applications of(1, 2)^*-generali... In this paper, the authors introduce and study the concept of (1, 2)^*-generalized closed sets with respect to an ideal in a bitopological space. Also, some characterizations and applications of(1, 2)^*-generalized closed sets are given. 展开更多
关键词 Bitopological space (1 2)^*-generalized closed set topological ideal.
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Intuitionistic Fuzzy α-Generalized Closed Sets in Terms of Minimal Structure Spaces
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作者 Mani Parimala Sivaraman Murali 《Circuits and Systems》 2016年第8期1486-1491,共6页
In this paper, we introduce the notion of intuitionistic fuzzy α-generalized closed sets in intuitionistic fuzzy minimal structure spaces and investigate some of their properties. Further, we introduce and study the ... In this paper, we introduce the notion of intuitionistic fuzzy α-generalized closed sets in intuitionistic fuzzy minimal structure spaces and investigate some of their properties. Further, we introduce and study the concept of intuitionistic fuzzy α-generalized minimal continuous functions. 展开更多
关键词 Intuitionistic Fuzzy Topology Intuitionistic Fuzzy α-Generalized closed set Intuitionistic Fuzzy α-Generalized Continuous Function Intuitionistic Fuzzy α-Generalized Continuous Mappings
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Finite-time stability with respect to a closed invariant set for a class of discontinuous systems 被引量:3
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作者 程桂芳 慕小武 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第8期1069-1075,共7页
This paper discusses the problem of finite-time stability with respect to a closed, but not necessarily compact, invariant set for a class of nonlinear systems with discontinuous right-hand sides in the sense of the F... This paper discusses the problem of finite-time stability with respect to a closed, but not necessarily compact, invariant set for a class of nonlinear systems with discontinuous right-hand sides in the sense of the Filippov solutions. When the Lyapunov function is Lipschitz continuous and regular, the Lyapunov theorem on finite-time stability with respect to a closed invariant set is presented. 展开更多
关键词 Filippov solution closed invariant set finite-time stability discontinuous system
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Rough similarity degree and rough close degree in rough fuzzy sets and the applications
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作者 Li Jian Xu Xiaojing Shi Kaiquan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第5期945-951,共7页
Based on rough similarity degree of rough sets and close degree of fuzzy sets, the definitions of rough similarity degree and rough close degree of rough fuzzy sets are given, which can be used to measure the similar ... Based on rough similarity degree of rough sets and close degree of fuzzy sets, the definitions of rough similarity degree and rough close degree of rough fuzzy sets are given, which can be used to measure the similar degree between two rough fuzzy sets. The properties and theorems are listed. Using the two new measures, the method of clustering in the rough fuzzy system can be obtained. After clustering, the new fuzzy sample can be recognized by the principle of maximal similarity degree. 展开更多
关键词 rough fuzzy set rough similarity degree rough close degree CLUSTERING recognition of rough pattern maximal similarity degree principle.
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On <i>M</i>-Asymmetric Semi-Open Sets and Semicontinuous Multifunctions in Bitopological Spaces 被引量:2
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作者 Levy K. Matindih Edwin Moyo 《Advances in Pure Mathematics》 2021年第4期218-236,共19页
The purpose of this paper is to introduce the notions of <em>m</em>-asymmetric semiopen sets and <em>M</em>-asymmetric semicontinuous multifunctions defined between asymmetric sets satisfying c... The purpose of this paper is to introduce the notions of <em>m</em>-asymmetric semiopen sets and <em>M</em>-asymmetric semicontinuous multifunctions defined between asymmetric sets satisfying certain minimal conditions in the framework of bitopological spaces. Some new characterizations of <em>m</em>-asymmetric semiopen sets and <em>M</em>-asymmetric semicontinuous multifunctions will be investigated and several fundamental properties will be obtained. 展开更多
关键词 m-Spaces m-Semiasymmetric Open and closed sets Upper and Lower M-Asymmetric Semicontinuous Multifunction
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用变异FP-树改进CLOSET算法
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作者 刘迎意 吴春旭 沈陵峰 《计算机仿真》 CSCD 北大核心 2010年第3期98-101,共4页
频繁闭项集提供了频繁项集的一种完整、最小表示,对频繁闭项集的挖掘是近年来数据挖掘领域研究的热点,研究人员从不同角度对算法改进以提高算法的效率。基于频繁项集中共生项集的性质,提出无须进行子集检查的频繁闭项集挖掘方法,并设计... 频繁闭项集提供了频繁项集的一种完整、最小表示,对频繁闭项集的挖掘是近年来数据挖掘领域研究的热点,研究人员从不同角度对算法改进以提高算法的效率。基于频繁项集中共生项集的性质,提出无须进行子集检查的频繁闭项集挖掘方法,并设计一种变异的FP-树结构,利用FP-树结构来存储结点共生项集信息,以改进CLOSET算法,算法无须遍历结果集进行闭合性检查。实验表明,在支持度阈值减小,结果集变大时,改进算法的时间增长率比原有算法小。 展开更多
关键词 数据挖掘 频繁闭项集 算法改进
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An Implanted Closed-loop Chip System for Heart Rate Control:System Design and Effects in Conscious Rats 被引量:3
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作者 Yuxuan Zhou Yuan Yuan +4 位作者 Juan Gao Ling Yang Feng Zhang Guoqing Zhu Xingya Gao 《The Journal of Biomedical Research》 CAS 2010年第2期107-114,共8页
Objective: To evaluate the efficiency of an implanted chip system for the control of heart rate (HR). Methods: The HR was recorded in six conscious Sprague-Dawley (SD) rats. An implanted chip system was designed... Objective: To evaluate the efficiency of an implanted chip system for the control of heart rate (HR). Methods: The HR was recorded in six conscious Sprague-Dawley (SD) rats. An implanted chip system was designed to regulate the HR by stimulating the right cervical vagus nerve according to the feedback of real time HR. Each rat was subjected to 30-min regulation and 30-min recovery. The change of HR during the regulation period was compared with the control. The ECG was recorded during the experiment for 24 h. Results: The ECG signals were successfully recorded during the experiment. The HR was significantly decreased during the period of regulation compared with control (-79.3 ± 34.5, P 〈 0.01, n = 6) and then recovered to normal after regulation. Conclusion: The described implanted chip system can regulate the HR to a designated set point. 展开更多
关键词 closed-loop regulation implanted chip system set point heart rate vagus nerve stimulation Remote-controlled animal
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Theorems of Helly's Type for Partially-closed Half-spaces
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作者 Liu Jian-Guo Guo Qi 《Communications in Mathematical Research》 CSCD 2018年第2期117-124,共8页
In this article, under quite weaker conditions, theorems of Helly’s type for(not necessarily finite) family of partially closed half-spaces are presented in both analytic and geometric forms. Examples are also provid... In this article, under quite weaker conditions, theorems of Helly’s type for(not necessarily finite) family of partially closed half-spaces are presented in both analytic and geometric forms. Examples are also provided to show that these conditions cannot be omitted in general. 展开更多
关键词 Helly's theorem partially-closed half-space affine function convex set
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非理想条件下基于SAADR-PI的MMC型电力电子变压器CCS-MPC控制策略
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作者 杨浩 周建萍 +1 位作者 黄烈钢 周靖涛 《南方电网技术》 CSCD 北大核心 2024年第9期11-22,共12页
基于模块化多电平换流器(modular multilevel converter,MMC)的电力电子变压器(power electronic transformer,PET)在非理想工况下易发生故障及扰动,严重影响系统电能质量。针对传统控制方法在非理想工况下存在的动稳态性能差等问题,在M... 基于模块化多电平换流器(modular multilevel converter,MMC)的电力电子变压器(power electronic transformer,PET)在非理想工况下易发生故障及扰动,严重影响系统电能质量。针对传统控制方法在非理想工况下存在的动稳态性能差等问题,在MMC-PET整流级提出了基于自适应自抗扰比例积分控制器的连续控制集模型预测控制策略。首先,设计了自适应自抗扰比例积分控制器用于电压外环,解决了电压外环信号跟踪及扰动抑制能力差等问题。其次,电流内环使用连续控制集模型预测控制方法以提高系统的响应速度及稳态性能,引入改进型载波移相调制策略解决桥臂电流畸变问题。最后,在网侧负载突变、网压不平衡、输出级负载投入等非理想工况下对MMC-PET系统进行对比仿真和实验,验证了所提控制策略的优越性。 展开更多
关键词 电力电子变压器 模块化多电平换流器 自适应自抗扰比例积分控制 连续控制集模型预测控制 双闭环控制
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Z-P-S空间中一类非线性算子方程解的研究 被引量:1
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作者 朱传喜 刘建辉 《应用数学》 CSCD 北大核心 2013年第2期424-430,共7页
本文利用Menger PN空间中半闭1-集压缩算子的拓扑度理论研究Z-P-S空间中非线性算子方程Ax=ux解的存在性问题,改进和推广了相关文献中的结果.最后,我们给出主要结果的一个具体应用.
关键词 Z—P—S空间 半闭1-集压缩算子 拓扑度 平衡集
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M-PN空间中u-集压缩算子拓扑度的计算(英文)
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作者 朱传喜 刘建辉 吴照奇 《应用数学》 CSCD 北大核心 2014年第2期420-425,共6页
本文研究M-PN空间中u-集压缩算子0<u<1拓扑度的计算问题,并且利用半闭1-集压缩算子的拓扑度理论研究一类非线性算子方程的解的存在性问题.最后,我们给出定理2.1的一个具体应用.
关键词 M—PN空间 u-集压缩算子 半闭1-集压缩算子 拓扑度
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On Drop and Weak Drop Properties for Bounded Closed Convex Sets*
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作者 张子厚 《Journal of Mathematical Research and Exposition》 CSCD 1999年第4期667-672,共6页
In this paper we prove three equivalent conditions of bounded closed convexset K in Banach space to have the drop and weak drop properties. We also give fourequivalent conditions of Banach space and its dual space to ... In this paper we prove three equivalent conditions of bounded closed convexset K in Banach space to have the drop and weak drop properties. We also give fourequivalent conditions of Banach space and its dual space to have the drop and weak dropproperties. 展开更多
关键词 Bounded closed convex set drop property weak drop property.
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M-PN空间中半闭1-集压缩算子方程解的存在性定理及其应用
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作者 朱传喜 徐文清 魏哲 《应用数学》 CSCD 北大核心 2015年第3期501-506,共6页
本文利用M-PN空间中的拓扑度性质以及一些不等式,建立半闭1-集压缩算子方程Ax=u(x+x0-y0)解的存在性定理,所得结果,推广了Leray-Schauder定理和最近相关文献中的结果.最后,给出主要结果的一些应用.
关键词 半闭1-集压缩算子 M-pN空间 不等式 拓扑度
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REMARKS OF DIFFERENTIAL EQUATIONS ON CLOSED SUBSETS IN A BANACH SPACE
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作者 范进军 庄万 《Annals of Differential Equations》 1997年第1期53-61,共9页
We give some extensions of Monch-Harton inequalities with respect to measures of noncompactness. As an example of the application, we obtain two existencetheorems of solutions for Cauchy problems of differential equat... We give some extensions of Monch-Harton inequalities with respect to measures of noncompactness. As an example of the application, we obtain two existencetheorems of solutions for Cauchy problems of differential equations on closed setsunder weaker compactness conditions. 展开更多
关键词 differential equations in Banach spaces solutions on closed sets noncompactness measure.
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Z-P-S空间中k-集压缩算子的固有值与固有元
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作者 朱传喜 刘建辉 《南昌大学学报(理科版)》 CAS 北大核心 2013年第6期511-513,522,共4页
首先在Menger PN空间中定义了k-集压缩算子的固有值与固有元这个新概念,然后利用Menger PN空间中半闭1-集压缩算子的拓扑度理论建立了Z-P-S空间中k-集压缩算子具有大于k的固有值λ和在D上存在对应于λ的固有元的若干充分条件。
关键词 Z-p-S空间 半闭1-集压缩算子 拓扑度
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Z-P-S空间中非线性算子方程Ax=μx的可解性
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作者 李娟 朱传喜 《南昌大学学报(理科版)》 CAS 北大核心 2015年第1期8-12,共5页
利用Menger概率线性赋范空间中半闭1-集压缩算子的拓扑度理论研究Z-P-S空间中非线性算子方程Ax=μx的可解性问题,所得结果推广了相关文献中的主要结果,并得到一些新的结果。最后,给出主要结果的一个具体应用。
关键词 Z-p-S空间 半闭1-集压缩算子 拓扑度 同伦不变性
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Lω-空间ω-p连通性的樊畿定理
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作者 徐小玲 马保国 《教育教学论坛》 2018年第19期196-197,共2页
在Lω-空间中借助ω-p闭集引入了ω-p远域,并借助ω-p远域给出了ω-p连通性的樊畿定理。
关键词 LΩ-空间 ω-p闭集 ω-p连通性 樊畿定理
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Z-P-S空间中半闭1-集压缩算子的固有值与固有元问题
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作者 罗婷 朱传喜 《应用泛函分析学报》 CSCD 2014年第3期227-232,共6页
利用拓扑度方法,本文在Z-P-S空间中研究了半闭1-集压缩算子的固有值与固有元问题,改进和推广了相关文献中的结果.
关键词 Z-p-S空间 半闭1-集压缩算子 MENGER PN空间 拓扑度.
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On the Equation n1n2= n3n4 Restricted to Factor Closed Sets
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作者 San Ying SHI Michel WEBER 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2018年第10期1517-1530,共14页
We study the number of solutions N(B,F) of the diophantine equation n1n2 = n3n4,where 1 ≤ n1≤B, 1≤ n3 ≤B, n2, n4 ∈ F and F C [1, B] is a factor closed set. We study more particularly the case when F = {m = p1^... We study the number of solutions N(B,F) of the diophantine equation n1n2 = n3n4,where 1 ≤ n1≤B, 1≤ n3 ≤B, n2, n4 ∈ F and F C [1, B] is a factor closed set. We study more particularly the case when F = {m = p1^ε1…pk^εk ,εj∈ {0, 1}, 1≤ j ≤ k}, p1,… ,pk being distinct prime numbers. 展开更多
关键词 Diophantine equation arithmetical functions factor closed set
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