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ON SOME RESULTS RELATED TO SOBER SPACES
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作者 李庆国 金梦洁 +1 位作者 苗化磷 陈思恒 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1477-1490,共14页
This paper investigates sober spaces and their related structures from different perspectives.First,we extend the descriptive set theory of second countable sober spaces to first countable sober spaces.We prove that a... This paper investigates sober spaces and their related structures from different perspectives.First,we extend the descriptive set theory of second countable sober spaces to first countable sober spaces.We prove that a first countable T_(0) space is sober if and only if it does not contain a∏_(2)^(0)-subspace homeomorphic either to S_(D),the natural number set equipped with the Scott topology,or to S_(1),the natural number set equipped with the cofinite topology,and it does not contain any directed closed subset without maximal elements either.Second,we show that if Y is sober,the function space TOP(X,Y)equipped with the Isbell topology(respectively,Scott topology)may be a non-sober space.Furthermore,we provide a uniform construction to d-spaces and well-filtered spaces via irreducible subset systems introduced in[9];we called this an H-well-filtered space.We obtain that,for a T_(0) space X and an H-well-filtered space Y,the function space TOP(X,Y)equipped with the Isbell topology is H-well-filtered.Going beyond the aforementioned work,we solve several open problems concerning strong d-spaces posed by Xu and Zhao in[11]. 展开更多
关键词 sober space descriptive set theory function space strong d-space product space REFLECTION
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A Monotonicity Condition for Strong Convergence of the Mann Iterative Sequence for Demicontractive Maps in Hilbert Spaces
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作者 Akuchu Besheng George Celestin Akwumbuom Nse 《Applied Mathematics》 2014年第15期2195-2198,共4页
Let?be a real Hilbert space and?C?be a nonempty closed convex subset of H. Let T : C?→?C?be a demicontractive map satisfying?〈Tx, x〉?≥?‖x‖2 for all?x?∈ D (T). Then the Mann iterative sequence given by?xn + 1?= ... Let?be a real Hilbert space and?C?be a nonempty closed convex subset of H. Let T : C?→?C?be a demicontractive map satisfying?〈Tx, x〉?≥?‖x‖2 for all?x?∈ D (T). Then the Mann iterative sequence given by?xn + 1?= (1 - an) xn +?anT xn, where an ∈?(0, 1) n?≥?0, converges strongly to an element of F (T):= {x?∈ C : Tx = x}. This strong convergence is obtained without the compactness-type assumptions on C, which many previous results (see e.g. [1]) employed. 展开更多
关键词 Demicontractive Maps MANN Iterative Sequence strong Convergence MONOTONICITY HILBERT spaces
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SOME METRIC AND TOPOLOGICAL PROPERTIES OF NEARLY STRONGLY AND NEARLY VERY CONVEX SPACES
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作者 张子厚 Vicente MONTESINOS 刘春燕 《Acta Mathematica Scientia》 SCIE CSCD 2020年第2期369-378,共10页
We obtain characterizations of nearly strong convexity and nearly very convexity by using the dual concept of S and WS points,related to the so-called Rolewicz’s property(α).We give a characterization of those point... We obtain characterizations of nearly strong convexity and nearly very convexity by using the dual concept of S and WS points,related to the so-called Rolewicz’s property(α).We give a characterization of those points in terms of continuity properties of the identity mapping.The connection between these two geometric properties is established,and finally an application to approximative compactness is given. 展开更多
关键词 Banach spaces nearly strongly convex spaces nearly very convex spaces Kadec property Radon-Riesz property approximative compactness
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SOME PROPERTIES OF STRONGLY MONOTONICALLY T2 SPACES
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作者 Zhao Bin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第4期469-474,共6页
This paper investigates Buck's question about which class of spaces is strongly monotonically T2,and if other properties are combined with strongly monotonically T2,which class of spaces could be got. Based on having... This paper investigates Buck's question about which class of spaces is strongly monotonically T2,and if other properties are combined with strongly monotonically T2,which class of spaces could be got. Based on having a cushioned pair-base space and compact strongly monotonically T2 space,some results (Theorems 1--3) are obtained. 展开更多
关键词 cushioned pair-base compact strongly monotonically T2 operator strongly monotonically T2 space.
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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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Iterative Approximation with Errors for Generalized Set-Valued Strongly Accretive Mapping in Banach Spaces
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作者 张勇 《Journal of Southwest Jiaotong University(English Edition)》 2007年第1期70-74,共5页
A new concept of generalized set-valued strongly accretive mappings in Banach spaces was given and some strong convergence theorems of Ishikawa and Mann iterative process with errors approximation methods by Huang et ... A new concept of generalized set-valued strongly accretive mappings in Banach spaces was given and some strong convergence theorems of Ishikawa and Mann iterative process with errors approximation methods by Huang et al. was proved. The results presented in this paper improve and extend the earlier results obtained by Huang et al. 展开更多
关键词 Generalized set-valued strongly accretive mappings Ishikawa and Mann iterative processes with errors q-Uniformly Smooth Banach spaces Generalized duality mapping
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CHEBYSHEV CENTERS PROXIMINALITY AND FARTHEST POINTS IN STRONG NORMED ALMOST LINEAR SPACES
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作者 Geetha S. Rao T. L. Bhaskaramurthi 《Analysis in Theory and Applications》 1997年第4期99-111,共13页
Some results from the theory of best (or best simultaneous) approximation in a narmed linear space have been extended to a normed almost linear space [strong normed almost linear space].
关键词 CHEBYSHEV CENTERS PROXIMINALITY AND FARTHEST POINTS IN strong NORMED ALMOST LINEAR spaces
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Iterative Approximation of Fixed Points for Uniformly Continuous and Strongly Pseudocontractive Mappings in Smooth Banach Spaces
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作者 周海云 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第2期42-46, ,共5页
With an inequality and some analysis techniques,iterative approximation of fixed points for uniformly continuous and strongly pseudocontractive mappings in smooth Banach spaces is studied,and the recent corresponding ... With an inequality and some analysis techniques,iterative approximation of fixed points for uniformly continuous and strongly pseudocontractive mappings in smooth Banach spaces is studied,and the recent corresponding results of Chidume are improved. 展开更多
关键词 光滑BANACH空间 一致连续 强伪压缩映射 不动点
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Stable Perturbed Algorithms for a New Class of Generalized Nonlinear Implicit Quasi Variational Inclusions in Banach Spaces 被引量:2
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作者 Salahuddin Salahuddin Mohammad Kalimuddin Ahmad 《Advances in Pure Mathematics》 2012年第3期139-148,共10页
In this work, a new class of variational inclusion involving T-accretive operators in Banach spaces is introduced and studied. New iterative algorithms for stability for their class of variational inclusions and its c... In this work, a new class of variational inclusion involving T-accretive operators in Banach spaces is introduced and studied. New iterative algorithms for stability for their class of variational inclusions and its convergence results are established. 展开更多
关键词 T-Accretive Operators VARIATIONAL INCLUSIONS Iterative Algorithms Stability Conditions Convergence strong Accretivity BANACH spaces
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GENERAL SPLIT FEASIBILITY PROBLEMS FOR TWO FAMILIES OF NONEXPANSIVE MAPPINGS IN HILBERT SPACES 被引量:1
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作者 唐金芳 张石生 刘敏 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期602-613,共12页
The purpose of this article is to introduce a general split feasibility problems for two families of nonexpansive mappings in Hilbert spaces. We prove that the sequence generated by the proposed new algorithm converge... The purpose of this article is to introduce a general split feasibility problems for two families of nonexpansive mappings in Hilbert spaces. We prove that the sequence generated by the proposed new algorithm converges strongly to a solution of the general split feasibility problem. Our results extend and improve some recent known results. 展开更多
关键词 General split feasibility problems nonexpansive mappings Hilbert space strong convergence
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SINGLE PROJECTION ALGORITHM FOR VARIATIONAL INEQUALITIES IN BANACH SPACES WITH APPLICATION TO CONTACT PROBLEM 被引量:3
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作者 Yekini SHEHU 《Acta Mathematica Scientia》 SCIE CSCD 2020年第4期1045-1063,共19页
We study the single projection algorithm of Tseng for solving a variational inequality problem in a 2-uniformly convex Banach space.The underline cost function of the variational inequality is assumed to be monotone a... We study the single projection algorithm of Tseng for solving a variational inequality problem in a 2-uniformly convex Banach space.The underline cost function of the variational inequality is assumed to be monotone and Lipschitz continuous.A weak convergence result is obtained under reasonable assumptions on the variable step-sizes.We also give the strong convergence result for when the underline cost function is strongly monotone and Lipchitz continuous.For this strong convergence case,the proposed method does not require prior knowledge of the modulus of strong monotonicity and the Lipschitz constant of the cost function as input parameters,rather,the variable step-sizes are diminishing and non-summable.The asymptotic estimate of the convergence rate for the strong convergence case is also given.For completeness,we give another strong convergence result using the idea of Halpern iteration when the cost function is monotone and Lipschitz continuous and the variable step-sizes are bounded by the inverse of the Lipschitz constant of the cost function.Finally,we give an example of a contact problem where our proposed method can be applied. 展开更多
关键词 variational inequality 2-uniformly convex Banach space Tseng’s algorithm strong convergence rate of convergence
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Some Topological Properties of Charming Spaces
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作者 Li Xiao-ting Lin Fu-cai Lin Shou 《Communications in Mathematical Research》 CSCD 2017年第2期110-120,共11页
In this paper, we mainly discuss the class of charming spaces. First, we show that there exists a charming space such that the Tychonoff product is not a charming space. Then we discuss some properties of charming spa... In this paper, we mainly discuss the class of charming spaces. First, we show that there exists a charming space such that the Tychonoff product is not a charming space. Then we discuss some properties of charming spaces and give some characterizations of some class of charming spaces. Finally, we show that the Suslin number of an arbitrary charming rectifiable space is countable. 展开更多
关键词 charming space (i j)-structured space lindelf Σ-space Suslin number rectifiable space
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Far-field analysis of effects of unilateral rupturing fault on the space correlation of strong ground motion
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作者 金星 陈超 +1 位作者 张明宇 高孟潭 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2000年第5期544-551,共8页
On the assumption that seismic source is simplified as linear rupture fault with finite length, this paper qualitatively studies the seismic source effects on space correlation of strong ground motion. Based on expand... On the assumption that seismic source is simplified as linear rupture fault with finite length, this paper qualitatively studies the seismic source effects on space correlation of strong ground motion. Based on expanding expression of Fourier spectrum of strong ground motion with space coordinate variables, this paper also gives a expression of describing correlation of strong ground motion field. According to far-field condition, the theoretical formula of the expression can be obtained. Furthermore, this paper presents a theoretical formula of estimation the radius of strong ground motion field, which depends on expansion condition of Fourier spectrum of strong ground motion, with space variables. At last, taking one earthquake as an example, this paper gives three-dimension patterns of radius of the field with epicenter distance and azimuth as well as frequency. 展开更多
关键词 one-direction rupture fault strong ground motion space correlation FAR-FIELD
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Common Fixed Point Iterations of Generalized Asymptotically Quasi-Nonexpansive Mappings in Hyperbolic Spaces
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作者 A. R. Khan H. Fukhar-ud-din 《Journal of Applied Mathematics and Physics》 2014年第5期170-175,共6页
We introduce a general iterative method for a finite family of generalized asymptotically quasi- nonexpansive mappings in a hyperbolic space and study its strong convergence. The new iterative method includes multi-st... We introduce a general iterative method for a finite family of generalized asymptotically quasi- nonexpansive mappings in a hyperbolic space and study its strong convergence. The new iterative method includes multi-step iterative method of Khan et al. [1] as a special case. Our results are new in hyperbolic spaces and generalize many known results in Banach spaces and CAT(0) spaces, simultaneously. 展开更多
关键词 HYPERBOLIC space General ITERATIVE Method Generalized ASYMPTOTICALLY Quasi-Nonexpansive Mapping Common Fixed Point strong Convergence
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A system of general nonlinear variational inclusions in Banach spaces
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作者 Xieping DING SALAHUDDIN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第12期1663-1672,共10页
A new system of general nonlinear variational inclusions is introduced and studied in Banach spaces. An iterative algorithm is developed and analyzed by use of the resolvent operator techniques to find the approximate... A new system of general nonlinear variational inclusions is introduced and studied in Banach spaces. An iterative algorithm is developed and analyzed by use of the resolvent operator techniques to find the approximate solutions of the system of general nonlinear variational inclusions involving different nonlinear operators in uniformly smooth Banach spaces. 展开更多
关键词 system of general nonlinear variational inclusions strongly accretive mapping relaxed accretive mapping resolvent operator uniformly smooth Banach space
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INTERACTION OF STRONG AND WEAK SINGULARITIES FOR HYPERBOLIC SYSTEM OF CONSERVATION LAWS IN MULTIDIMENSIONAL SPACE
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作者 陈恕行 《Acta Mathematica Scientia》 SCIE CSCD 1990年第3期298-302,共5页
In this paper we study the interaction of strong and weak singularities for hyperbolic system of conservation laws in multidimensional space. Under the assumption of transversal intersect of the shock front with the b... In this paper we study the interaction of strong and weak singularities for hyperbolic system of conservation laws in multidimensional space. Under the assumption of transversal intersect of the shock front with the bicharacteristics bearing weak singularities we proved a theorem on regularity propagation across the shock front. 展开更多
关键词 INTERACTION OF strong AND WEAK SINGULARITIES FOR HYPERBOLIC SYSTEM OF CONSERVATION LAWS IN MULTIDIMENSIONAL space
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Study of Nonlinear Earthquake Flow Functions and Their Application to the Space Increased Probability of Strong Earthquake (SIP)
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作者 Wang Xiaoqing and Huang DeyuCenter for Analysis and Prediction, CSB, Beijing 100036, China 《Earthquake Research in China》 1998年第3期37-47,共11页
The definition and abnormality discriminatory criteria of earthquake flow function are introduced in this paper based on the algorithm of Space Increased Probability (SIP). Nine earthquake flow functions were defined ... The definition and abnormality discriminatory criteria of earthquake flow function are introduced in this paper based on the algorithm of Space Increased Probability (SIP). Nine earthquake flow functions were defined by the method. The retrospect test that applied the SIP algorithm with the nonlinear earthquake flow function to 7 earthquakes, which occurred from 1975 to 1989 in Eastern China, with a magnitude of 6 or greater depicted that 6 of the 7 strong earthquakes (86%) were located in the SIP areas, and the SIP covers about 32% of the total research time-space domain. These suggest that the R-value, an effective scale for earthquake forecast, is 54% and may imply that the nonlinear earthquake flow function introduced in this paper can be applied to the intermediate-term earthquake forecast research. 展开更多
关键词 NONLINEAR EARTHQUAKE flow function space INCREASED PROBABILITY of strong earthquake.
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Curvature Estimates for Strongly Stable Domains on Surfaces with Constant Mean Curvature in Space Forms
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作者 王治国 吴志勤 孙敏 《Chinese Quarterly Journal of Mathematics》 CSCD 1994年第3期49-52,共4页
CurvatureEstimatesforStronglyStableDomainsonSurfaceswithConstantMeanCurvatureinSpaceForms(WangZhiguo);(王治国)(... CurvatureEstimatesforStronglyStableDomainsonSurfaceswithConstantMeanCurvatureinSpaceForms(WangZhiguo);(王治国)(WuZhiqing);(吴志勤)(... 展开更多
关键词 CURVATURE estheate strongLY STABLE surface CONSTANT mean CURVATURE space form
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能量选择电磁防护方法理论与应用
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作者 刘培国 虎宁 《电波科学学报》 CSCD 北大核心 2024年第3期385-394,431,共11页
随着信息技术的发展,电磁空间逐渐成为国家重大公共基础设施及信息网络的基石。近年来,强电磁源生成技术加速发展,对电磁空间安全形成严重威胁,开展强电磁防护技术研究具有迫切的现实需求。能量选择防护方法是一种新型自适应强电磁防护... 随着信息技术的发展,电磁空间逐渐成为国家重大公共基础设施及信息网络的基石。近年来,强电磁源生成技术加速发展,对电磁空间安全形成严重威胁,开展强电磁防护技术研究具有迫切的现实需求。能量选择防护方法是一种新型自适应强电磁防护方法,突破了电子设备前门防护“能防”和“兼容”的难题,为强电磁防护提供了新的技术思路。本文对能量选择防护方法进行了系统综述,首先详细介绍了能量选择防护的内涵和相关概念;其次以能量选择表面为例阐述了其工作原理与实现方式,在此基础上对能量选择防护方法的研究现状和最新成果进行介绍,梳理了能量选择防护方法的发展脉络;最后,对能量选择防护方法的未来研究方向进行了展望。 展开更多
关键词 电磁安全 强电磁防护 前门防护 能量选择 自适应响应
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FT-粗糙集模型的一些性质
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作者 张纪平 周缪娟 李进金 《泉州师范学院学报》 2024年第2期1-9,共9页
T-粗糙集是Pawlak粗糙集理论发展过程中的一个重要模型,已成功应用于数据挖掘等诸多领域.FT-粗糙集模型能够在保持数据的完整性下处理连续型数据,是对仅能处理离散型数据的T-粗糙集模型上的发展.文章引入模糊近似空间(X,Y,T)一对模糊集... T-粗糙集是Pawlak粗糙集理论发展过程中的一个重要模型,已成功应用于数据挖掘等诸多领域.FT-粗糙集模型能够在保持数据的完整性下处理连续型数据,是对仅能处理离散型数据的T-粗糙集模型上的发展.文章引入模糊近似空间(X,Y,T)一对模糊集的弱逆和强逆定义,用量化方法研究FT-粗糙集的一些性质,得到模糊技能映射在析取模型、合取模型下分别生成的知识结构;用量化方法与矩阵表示探究FT-粗糙集模糊集值映射在并、交运算下的性质. 展开更多
关键词 FT-粗糙集 模糊近似空间 下逆和上逆 弱逆和强逆
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