期刊文献+
共找到1,726篇文章
< 1 2 87 >
每页显示 20 50 100
On Fuzzy Regularly Closed Filters in Michálek Fuzzy Topological Space
1
作者 Puthenpurackal Ratnakumar Neethu Bloomy Joseph 《Advances in Pure Mathematics》 2024年第10期779-784,共6页
C.L. Chang’s introduction of fuzzy topology in 1981 opened up new avenues for parallel theories in topology. However, Chang’s work appears to focus more on the topology of fuzzy sets rather than fuzzy topology itsel... C.L. Chang’s introduction of fuzzy topology in 1981 opened up new avenues for parallel theories in topology. However, Chang’s work appears to focus more on the topology of fuzzy sets rather than fuzzy topology itself. In 1975, Michálek presented a functional definition of ordinary topology and later developed fuzzy topology as a distinct extension of this idea, setting it apart from Chang’s approach. While there has been significant research on Chang’s fuzzy topology, Michálek’s version has not received as much attention. This paper introduces the concept of fuzzy regularly closed filters, or FRCM filters, within Michálek’s fuzzy topological space and explores some properties of FRCM ultrafilters. 展开更多
关键词 TOPOLOGY fuzzy Topology Michálek’s fuzzy Topological space fuzzy Closed fuzzy Open FILTERS
下载PDF
Fuzzy c-means text clustering based on topic concept sub-space 被引量:3
2
作者 吉翔华 陈超 +1 位作者 邵正荣 俞能海 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期439-442,共4页
To improve the accuracy of text clustering, fuzzy c-means clustering based on topic concept sub-space (TCS2FCM) is introduced for classifying texts. Five evaluation functions are combined to extract key phrases. Con... To improve the accuracy of text clustering, fuzzy c-means clustering based on topic concept sub-space (TCS2FCM) is introduced for classifying texts. Five evaluation functions are combined to extract key phrases. Concept phrases, as well as the descriptions of final clusters, are presented using WordNet origin from key phrases. Initial centers and membership matrix are the most important factors affecting clustering performance. Orthogonal concept topic sub-spaces are built with the topic concept phrases representing topics of the texts and the initialization of centers and the membership matrix depend on the concept vectors in sub-spaces. The results show that, different from random initialization of traditional fuzzy c-means clustering, the initialization related to text content contributions can improve clustering precision. 展开更多
关键词 TCS2FCM topic concept space fuzzy c-means clustering text clustering
下载PDF
Metamodel-based Global Optimization Using Fuzzy Clustering for Design Space Reduction 被引量:13
3
作者 LI Yulin LIU Li +1 位作者 LONG Teng DONG Weili 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第5期928-939,共12页
High fidelity analysis are utilized in modern engineering design optimization problems which involve expensive black-box models.For computation-intensive engineering design problems,efficient global optimization metho... High fidelity analysis are utilized in modern engineering design optimization problems which involve expensive black-box models.For computation-intensive engineering design problems,efficient global optimization methods must be developed to relieve the computational burden.A new metamodel-based global optimization method using fuzzy clustering for design space reduction(MGO-FCR) is presented.The uniformly distributed initial sample points are generated by Latin hypercube design to construct the radial basis function metamodel,whose accuracy is improved with increasing number of sample points gradually.Fuzzy c-mean method and Gath-Geva clustering method are applied to divide the design space into several small interesting cluster spaces for low and high dimensional problems respectively.Modeling efficiency and accuracy are directly related to the design space,so unconcerned spaces are eliminated by the proposed reduction principle and two pseudo reduction algorithms.The reduction principle is developed to determine whether the current design space should be reduced and which space is eliminated.The first pseudo reduction algorithm improves the speed of clustering,while the second pseudo reduction algorithm ensures the design space to be reduced.Through several numerical benchmark functions,comparative studies with adaptive response surface method,approximated unimodal region elimination method and mode-pursuing sampling are carried out.The optimization results reveal that this method captures the real global optimum for all the numerical benchmark functions.And the number of function evaluations show that the efficiency of this method is favorable especially for high dimensional problems.Based on this global design optimization method,a design optimization of a lifting surface in high speed flow is carried out and this method saves about 10 h compared with genetic algorithms.This method possesses favorable performance on efficiency,robustness and capability of global convergence and gives a new optimization strategy for engineering design optimization problems involving expensive black box models. 展开更多
关键词 global optimization metamodel-based optimization reduction of design space fuzzy clustering
下载PDF
Prime MP-filter Spaces of Fuzzy Implication Algebras 被引量:8
4
作者 LIU Chun-hui XU Luo-shan 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第2期246-253,共8页
In this paper,the topological space(PF_(MP)(X),T) based on prime MP-filters of a lattice FI-algebra X is constructed firstly and we proved that it is a compact T_0-space if X with condition(P).Secondly,we restricted T... In this paper,the topological space(PF_(MP)(X),T) based on prime MP-filters of a lattice FI-algebra X is constructed firstly and we proved that it is a compact T_0-space if X with condition(P).Secondly,we restricted T to the set of all maximal MP-filters MF_(MP)(X) of X and concluded that(PF_(MP)(X),T |_(PF_(MP)(X)) )is a compact T_2 space if X with conditions(P) and(S). 展开更多
关键词 fuzzy implication algebra MP-FILTER prime MP-filter topological space
下载PDF
NL-fuzzy拓扑空间中的N-紧性
5
作者 王小霞 高佳欣 李乔乔 《沈阳大学学报(自然科学版)》 CAS 2024年第4期364-368,共5页
利用α-远域族定义了NL-fuzzy拓扑空间中的N-紧性,借助α-分子网,模糊滤子以及模糊滤子基的概念给出其等价刻画。证明了N-紧性具有拓扑不变性以及有限多个N-紧集的并仍为N-紧集等性质。
关键词 NL-fuzzy拓扑空间 α-远域族 N-紧性 模糊滤子 拓扑不变性
下载PDF
Rough communication of crisp concept in fuzzy approximation spaces 被引量:3
6
作者 Wang Hongkai Guan Yanyong Yu Zhaoxia 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期327-331,共5页
To study the problem of knowledge translation in fuzzy approximation spaces, the concept of rough communication of crisp set in fuzzy approximation spaces is proposed. In a rough communication of crisp set in fuzzy ap... To study the problem of knowledge translation in fuzzy approximation spaces, the concept of rough communication of crisp set in fuzzy approximation spaces is proposed. In a rough communication of crisp set in fuzzy approximation spaces, the problem of uncertainty exists, for each agent has a different language and cannot provide precise communication to each other. By means of some concepts, such as CF rough communication cut, which is a bridge between fuzzy concept and crisp concept, cut analysis of CF rough communication is made, and the relation theorem between CF rough communication and rough communication of crisp concept is obtained. Finally, in order to give an intuitive analysis of the relation between CF rough communication and rough communication of crisp concept, an example is given. 展开更多
关键词 rough sets fuzzy approximation space crisp concept rough communication CF rough communication cut
下载PDF
Common Fixed Point Theorems in Intuitionistic Fuzzy Metric Spaces 被引量:3
7
作者 Saurabh Manro Sanjay Kumar Shivdeep Singh 《Applied Mathematics》 2010年第6期510-514,共5页
In this paper, we introduce the concept of – chainable intuitionistic fuzzy metric space akin to the notion of – chainable fuzzy metric space introduced by Cho, and Jung [1] and prove a common fixed point theorem fo... In this paper, we introduce the concept of – chainable intuitionistic fuzzy metric space akin to the notion of – chainable fuzzy metric space introduced by Cho, and Jung [1] and prove a common fixed point theorem for weakly compatible mappings in this newly defined space. 展开更多
关键词 Chainable Intuitionistic fuzzy METRIC space WEAKLY Compatible MAPS
下载PDF
Fixed Point Results by Altering Distances in Fuzzy Metric Spaces 被引量:2
8
作者 Ibtisam Masmali Sumitra Dalal Nasir Rehman 《Advances in Pure Mathematics》 2015年第6期377-382,共6页
We establish fixed point theorems in complete fuzzy metric space by using notion of altering distance, initiated by Khan et al. [Bull. Austral. Math. Soc. 30 (1984), 1-9]. Also, we find an affirmative answer in fuzzy ... We establish fixed point theorems in complete fuzzy metric space by using notion of altering distance, initiated by Khan et al. [Bull. Austral. Math. Soc. 30 (1984), 1-9]. Also, we find an affirmative answer in fuzzy metric space to the problem of Sastry [TamkangJ. Math., 31(3) (2000), 243-250]. 展开更多
关键词 Fixed POINTS fuzzy METRIC spaceS Altering Distance Fixed Point RESULTS
下载PDF
T_2 Separation Subsets and T_2 Separateness in L-fuzzy Topological Spaces 被引量:3
9
作者 孟广武 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第2期11-18, ,共8页
The concept of α-CT2 separation L-fuzzy subsets in L-fuzzy topological spaces is presented by taking the stratiform structure of L-fuzzy subsets as the point of departure,and its basic characterizations and some topo... The concept of α-CT2 separation L-fuzzy subsets in L-fuzzy topological spaces is presented by taking the stratiform structure of L-fuzzy subsets as the point of departure,and its basic characterizations and some topological properties are discussed,and the relation between it and other separateness is exposed,and the action is studied of α-CT2 separateness in N-compact spaces and N-paracompact spaces. 展开更多
关键词 fuzzy topological space α-CT_2 separation subset fuzzy lattice stratiform structure
下载PDF
Common Fixed Points of Single and Multivalued Maps in Fuzzy Metric Spaces 被引量:1
10
作者 Palaniappan Vijayaraju Zahurullah Mohamed Ibrahim Sajath 《Applied Mathematics》 2011年第5期595-599,共5页
In this paper we introduce the notion of common property (EA) in fuzzy metric spaces. Further we prove some common fixed points theorems for hybrid pair of single and multivalued maps under hybrid contractive conditio... In this paper we introduce the notion of common property (EA) in fuzzy metric spaces. Further we prove some common fixed points theorems for hybrid pair of single and multivalued maps under hybrid contractive conditions. Our results extend previous ones in fuzzy metric spaces. 展开更多
关键词 fuzzy METRIC space COMMON Fixed POINT COINCIDENCE Point.
下载PDF
Common Fixed Point Theorems for Weakly Compatible Mappings in Fuzzy Metric Spaces Using (JCLR) Property 被引量:1
11
作者 Sunny Chauhan Wutiphol Sintunavarat Poom Kumam 《Applied Mathematics》 2012年第9期976-982,共7页
In this paper, we prove a common fixed point theorem for a pair of weakly compatible mappings in fuzzy metric space using the joint common limit in the range property of mappings called (JCLR) property. An example is ... In this paper, we prove a common fixed point theorem for a pair of weakly compatible mappings in fuzzy metric space using the joint common limit in the range property of mappings called (JCLR) property. An example is also furnished which demonstrates the validity of main result. We also extend our main result to two finite families of self mappings. Our results improve and generalize results of Cho et al. [Y. J. Cho, S. Sedghi and N. Shobe, “Generalized fixed point theorems for compatible mappings with some types in fuzzy metric spaces,” Chaos, Solitons & Fractals, Vol. 39, No. 5, 2009, pp. 2233-2244.] and several known results existing in the literature. 展开更多
关键词 fuzzy Metric space WEAKLY Compatible MAPPINGS (E.A) PROPERTY (CLR) PROPERTY (JCLR) PROPERTY
下载PDF
Some New Fixed Point Theorems for Fuzzy Iterated Contraction Maps in Fuzzy Metric Spaces 被引量:1
12
作者 Lei Xia Yuehan Tang 《Journal of Applied Mathematics and Physics》 2018年第1期228-231,共4页
The purpose of this paper is to introduce the notion of fuzzy iterated contraction maps in fuzzy metric spaces and establish some new fixed point theorems for fuzzy iterated contraction maps in fuzzy metric spaces.
关键词 Fixed Point ITERATED CONTRACTION Map fuzzy METRIC space
下载PDF
The Fuzzy Neural Network Control Scheme With H∞ Tracking Characteristic of Space Robot System With Dual-arm After Capturing a Spin Spacecraft 被引量:1
13
作者 Jing Cheng Li Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第5期1417-1424,共8页
In this paper,the dynamic evolution for a dualarm space robot capturing a spacecraft is studied,the impact effect and the coordinated stabilization control problem for postimpact closed chain system are discussed.At f... In this paper,the dynamic evolution for a dualarm space robot capturing a spacecraft is studied,the impact effect and the coordinated stabilization control problem for postimpact closed chain system are discussed.At first,the pre-impact dynamic equations of open chain dual-arm space robot are established by Lagrangian approach,and the dynamic equations of a spacecraft are obtained by Newton-Euler method.Based on the results,with the process of integral and simplify,the response of the dual-arm space robot impacted by the spacecraft is analyzed by momentum conservation law and force transfer law.The closed chain system is formed in the post-impact phase.Closed chain constraint equations are obtained by the constraints of closed-loop geometry and kinematics.With the closed chain constraint equations,the composite system dynamic equations are derived.Secondly,the recurrent fuzzy neural network control scheme is designed for calm motion of unstable closed chain system with uncertain system parameter.In order to overcome the effects of uncertain system inertial parameters,the recurrent fuzzy neural network is used to approximate the unknown part,the control method with H∞tracking characteristic.According to the Lyapunov theory,the global stability is demonstrated.Meanwhile,the weighted minimum-norm theory is introduced to distribute torques guarantee that cooperative operation between manipulators.At last,numerical examples simulate the response of the collision,and the efficiency of the control scheme is verified by the simulation results. 展开更多
关键词 Capturing operation calm motion control closed chain system dual-arm space robot recurrent fuzzy neural network H∞tracking characteristic
下载PDF
The Application of Fuzzy Evaluation based on GIS in Tianjin Urban Underground Space Resource Appraisal
14
作者 Fang Xu~(1,2),Jian Shen~1 1.Department of City Geology,Tianjin Institute of Geological Survey,Tianjin 300191,China. 2.Faculty of Resource and Safety Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期186-186,共1页
The exploitation and utilization of the city underground space resource is the important approach of building tri-dimensional and ecological cities, solving the environment,resource,and population crisis and continuin... The exploitation and utilization of the city underground space resource is the important approach of building tri-dimensional and ecological cities, solving the environment,resource,and population crisis and continuing cities development.This article, based on the introduction in detail the overview of regional geology,hydrogeologic condition,engineering geology,environmental geology,etc.in center city of Tianjin,establishes evaluating model of urban underground space resource based on GIS 展开更多
关键词 GEOLOGY information system fuzzy evaluation UNDERGROUND space RESOURCE APPRAISAL TIANJIN
下载PDF
Normality and Its Variants on Fuzzy Isotone Spaces
15
作者 Stephen M. Gathigi Moses N. Gichuki +1 位作者 Paul A. Otieno Hezron S. Were 《Advances in Pure Mathematics》 2013年第7期639-642,共4页
The study of fuzzy sets is specifically designed to mathematically represent uncertainty and vagueness by assigning values of membership to objects that belong to a particular set. This notion has been broadly extende... The study of fuzzy sets is specifically designed to mathematically represent uncertainty and vagueness by assigning values of membership to objects that belong to a particular set. This notion has been broadly extended to other areas of topology where various topological concepts have been shown to hold on fuzzy topology. Some notions naturally extend to closure spaces without requiring a lot of modification of the underlying topological ideas. This work investigates the variants of normality on fuzzy isotone spaces. 展开更多
关键词 fuzzy Sets fuzzy CLOSURE space fuzzy Isotone space fuzzy NORMALITY
下载PDF
Almost Fuzzy Compactness in L-fuzzy Topological Spaces
16
作者 Li Hong-yan Cui Wei Lei Feng-chun 《Communications in Mathematical Research》 CSCD 2015年第3期267-273,共7页
In this paper, the notion of almost fuzzy compactness is dened in L-fuzzy topological spaces by means of inequality, where L is a completely distributiveDeMorgan algebra. Its properties are discussed and many characte... In this paper, the notion of almost fuzzy compactness is dened in L-fuzzy topological spaces by means of inequality, where L is a completely distributiveDeMorgan algebra. Its properties are discussed and many characterizations of it arepresented. 展开更多
关键词 L-fuzzy topological space L-fuzzy almost compactness L-fuzzy compactness almost fuzzy compactness
下载PDF
General Type-2 Fuzzy Topological Spaces
17
作者 Munir Abdul Khalik AL-Khafaji Mohammed Salih Mahdy Hussan 《Advances in Pure Mathematics》 2018年第9期771-781,共11页
In this paper, a presented definition of type-2 fuzzy sets and type-2 fuzzy set operation on it was given. The aim of this work was to introduce the concept of general topological spaces were extended in type-2 fuzzy ... In this paper, a presented definition of type-2 fuzzy sets and type-2 fuzzy set operation on it was given. The aim of this work was to introduce the concept of general topological spaces were extended in type-2 fuzzy sets with the structural properties such as open sets, closed sets, interior, closure and neighborhoods in topological spaces were extended to general type-2 fuzzy topological spaces and many related theorems are proved. 展开更多
关键词 Type-2 fuzzy SET Interval Type-2 fuzzy TOPOLOGICAL space GENERAL Type-2 fuzzy TOPOLOGICAL spaces Type-2 fuzzy Open SETS Type-2 fuzzy Closed SETS Type-2 fuzzy Interior Type-2 fuzzy Closure Neighborhood of a Type-2 fuzzy SET
下载PDF
Unique Solution of Integral Equations via Intuitionistic Extended Fuzzy b-Metric-Like Spaces
18
作者 Naeem Saleem Khalil Javed +4 位作者 Fahim Uddin Umar Ishtiaq Khalil Ahmed Thabet Abdeljawad Manar A.Alqudah 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期109-131,共23页
In this manuscript,our goal is to introduce the notion of intuitionistic extended fuzzy b-metric-like spaces.We establish some fixed point theorems in this setting.Also,we plot some graphs of an example of obtained re... In this manuscript,our goal is to introduce the notion of intuitionistic extended fuzzy b-metric-like spaces.We establish some fixed point theorems in this setting.Also,we plot some graphs of an example of obtained result for better understanding.We use the concepts of continuous triangular norms and continuous triangular conorms in an intuitionistic fuzzy metric-like space.Triangular norms are used to generalize with the probability distribution of triangle inequality in metric space conditions.Triangular conorms are known as dual operations of triangular norms.The obtained results boost the approaches of existing ones in the literature and are supported by some examples and applications. 展开更多
关键词 Fixed point extended fuzzy b-metric like space intuitionistic extended fuzzy b-metric-like space integral equation
下载PDF
Fuzzy optimization of space frame
19
作者 ZaigenMu ZheWu 《Journal of University of Science and Technology Beijing》 CSCD 2002年第2期145-148,共4页
Fuzzy concepts are introduced into structural optimization to solve fuzzyoptimization problems with a crisp objective function and fuzzy constraints, also a non-membershipfunction is used to convert fuzzy constrains i... Fuzzy concepts are introduced into structural optimization to solve fuzzyoptimization problems with a crisp objective function and fuzzy constraints, also a non-membershipfunction is used to convert fuzzy constrains into crisp constrains. Two models are discussed wherethe objective function considered is the volume of space frame and the fuzzy constrains are designlimits by the axial strength, slenderness, deflection, thickness and diameter of space frame member. 展开更多
关键词 space frame fuzzy optimization geometric non-linearity
下载PDF
Common Fixed Point Theorem in Intuitionistic Fuzzy Metric Space Using <i>R</i>-Weakly Commuting Mappings
20
作者 Saurabh Manro Satwinder Singh Bhatia Sanjay Kumar 《Applied Mathematics》 2012年第3期225-230,共6页
In this paper, we prove a common fixed point theorem in Intuitionistic fuzzy metric space by using pointwise R-weak commutativity and reciprocal continuity of mappings satisfying contractive conditions.
关键词 Intuitionistic fuzzy Metric space Reciprocal Continuity R-Weakly COMMUTING Mappings Common Fixed Point THEOREM
下载PDF
上一页 1 2 87 下一页 到第
使用帮助 返回顶部