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Generalized projective synchronization of the fractional-order chaotic system using adaptive fuzzy sliding mode control 被引量:3
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作者 王立明 唐永光 +1 位作者 柴永泉 吴峰 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期64-70,共7页
An adaptive fuzzy sliding mode strategy is developed for the generalized projective synchronization of a fractional- order chaotic system, where the slave system is not necessarily known in advance. Based on the desig... An adaptive fuzzy sliding mode strategy is developed for the generalized projective synchronization of a fractional- order chaotic system, where the slave system is not necessarily known in advance. Based on the designed adaptive update laws and the linear feedback method, the adaptive fuzzy sliding controllers are proposed via the fuzzy design, and the strength of the designed controllers can he adaptively adjusted according to the external disturbances. Based on the Lya- punov stability theorem, the stability and the robustness of the controlled system are proved theoretically. Numerical simu- lations further support the theoretical results of the paper and demonstrate the efficiency of the proposed method. Moreover, it is revealed that the proposed method allows us to manipulate arbitrarily the response dynamics of the slave system by adjusting the desired scaling factor λi and the desired translating factor ηi, which may be used in a channel-independent chaotic secure communication. 展开更多
关键词 generalized projective chaos synchronization fuzzy sliding mode control fractional order chaoticsystem
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Minimization of Fuzzy Finite Generalized Automata 被引量:2
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作者 莫智文 胡红莉 《Journal of Electronic Science and Technology of China》 CAS 2006年第1期86-88,共3页
Some concepts in Fuzzy Generalized Automata (FGA) are established. Then an important new algorithm which would calculate the minimal FGA is given. The new algorithm is composed of two parts: the first is called E-r... Some concepts in Fuzzy Generalized Automata (FGA) are established. Then an important new algorithm which would calculate the minimal FGA is given. The new algorithm is composed of two parts: the first is called E-reduction which contracts equivalent states, and the second is called RE-reduction which removes retrievable states. Finally an example is given to illuminate the algorithm of minimization. 展开更多
关键词 fuzzy language fuzzy finite state automata fuzzy generalized Automata(FGA) minimal automata
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Category of Generalized Intuitionistic Fuzzy Sets 被引量:1
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作者 YANGWan-cai LIXiao-shen 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第2期192-199,共8页
In this paper, category GIFS of generalized intuitionistic fuzzy sets(GIF) is built up. Topoi properties of category GIFS are studied. Firstly, it is proved that the category GIFS has all topoi properties except that ... In this paper, category GIFS of generalized intuitionistic fuzzy sets(GIF) is built up. Topoi properties of category GIFS are studied. Firstly, it is proved that the category GIFS has all topoi properties except that it has no subobject classifiers, Secondly, it is proved that the category GIFS has middle object and consequently GIFS is a weak topos. Thirdly, by the use of theory of weak topos GIFS, the power object of an object in GIFS is studied. 展开更多
关键词 CATEGORY TOPOS middle object weak topos generalized intuitionistic fuzzy set
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Minimum Cycle of Row Vector of a Generalized Circulant Fuzzy Matrix
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作者 冼国荣 陈卓荣 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第1期104-110, ,共7页
In this paper,we intreduce the concept and discuss the properties of minimum cycle of row vector in a generalized circulant Fuzzy matrix. We present a new expression for circulant Fuzzy matrix,and discuss some propert... In this paper,we intreduce the concept and discuss the properties of minimum cycle of row vector in a generalized circulant Fuzzy matrix. We present a new expression for circulant Fuzzy matrix,and discuss some properties of the idempotent elements of the semigroup of generalized circulant Fuzzy matrixes in connection with minimum cycle of row vector. 展开更多
关键词 generalized circulant fuzzy matrix SEMIGROUP VECTOR CYCLE idempotent element
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Strongly Generalized Convex Fuzzy-Valued Function and Its Application in Fuzzy Optimization
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作者 BAI Yu-juan LIU Kun ZHANG Chen 《Chinese Quarterly Journal of Mathematics》 2020年第4期370-387,共18页
Based on the ordering of fuzzy numbers proposed by Goetschel and Voxman,the representations and some properties of strongly preinvex fuzzy-valued function are defined and obtained, several new concepts of strongly mon... Based on the ordering of fuzzy numbers proposed by Goetschel and Voxman,the representations and some properties of strongly preinvex fuzzy-valued function are defined and obtained, several new concepts of strongly monotonicities fuzzy functions are introduced, the relationship among the strongly preinvex, strongly invex and monotonicities under some suitable and appropriate conditions is established and a necessary condition for strongly pseudoinvex functions is given. As an application, the conditions of local optimal solution and global optimal solution in the mathematical programming problem are discussed. 展开更多
关键词 fuzzy-number-valued functions Strongly generalized convexity fuzzy optimization
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Algorithm of solutions for generalized nonlinear implicit quasivariational inclusions with fuzzy mappings
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作者 胡学刚 《Journal of Chongqing University》 CAS 2006年第1期36-41,共6页
A class of generalized implicit quasivariational inclusions with fuzzy mappings in Hilbert space is discussed in this paper which proves an existence theorem of the solutions and proposes a new iterative algorithm and... A class of generalized implicit quasivariational inclusions with fuzzy mappings in Hilbert space is discussed in this paper which proves an existence theorem of the solutions and proposes a new iterative algorithm and the convergence of the iterative sequence generated by the new algorithm. These results extend and improve some recent corresponding achievements. 展开更多
关键词 generalized nonlinear implicit quasivariational inclusion with fuzzy mappings existence theorem of solutions ITERATIVE
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Fault Diagnosing System of Steam Generator for Nuclear Power Plant Based on Fuzzy Neural Networks
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作者 Ming-Yu Fu Xin-Qian Bian Ji Shi 《Journal of Marine Science and Application》 2002年第1期41-46,共6页
All kinds of reasons are analysed in theory and a fault repository combined with local expert experiences is establishedaccording to the structure and the operation characteristic of steam generator in this paper. At ... All kinds of reasons are analysed in theory and a fault repository combined with local expert experiences is establishedaccording to the structure and the operation characteristic of steam generator in this paper. At the same time, Kohonen algo-rithm is used for fault diagnoses system based on fuzzy neural networks. Fuzzy arithmetic is inducted into neural networks tosolve uncertain diagnosis induced by uncertain knowledge. According to its self-association in the course of default diagnosis. thesystem is provided with non-supervise, self-organizing, self-learning, and has strong cluster ability and fast cluster velocity. 展开更多
关键词 NEURAL NETWORK STEAM generATOR fuzzy FAULT diagnosing
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A Fuzzy Logical MPPT Control Strategy for PMSG Wind Generation Systems
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作者 Xing-Peng Li Wen-Lu Fu +2 位作者 Qing-Jun Shi Jian-Bing Xu Quan-Yuan Jiang 《Journal of Electronic Science and Technology》 CAS 2013年第1期72-77,共6页
Making full use of wind power is one of the main purposes of the wind turbine generator control. Conventional hill climbing search (HCS) method can realize the maximum power point tracking (MPPT). However, the ste... Making full use of wind power is one of the main purposes of the wind turbine generator control. Conventional hill climbing search (HCS) method can realize the maximum power point tracking (MPPT). However, the step size of HCS method is constant so that it cannot consider both steady-state response and dynamic response. A fuzzy logical control (FLC) algorithm is proposed to solve this problem in this paper, which can track the maximum power point (MPP) quickly and smoothly. To evaluate MPPT algorithms, four performance indices are also proposed in this paper. They are the energy captured by wind turbine, the maximum power-point tracking time when wind speed changes slowly, the fluctuation magnitude of real power during steady state, and the energy captured by wind turbine when wind speed changes fast. Three cases are designed and simulated in MATLAB/Simulink respectively. The comparison of the three MPPT strategies concludes that the proposed fuzzy logical control algorithm is more superior to the conventional HCS algorithms. 展开更多
关键词 fuzzy logical control hill climbing search maximum power point tracking permanent magnet synchronous generator wind generation system.
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Kernel Generalized Noise Clustering Algorithm
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作者 武小红 周建江 《Journal of Southwest Jiaotong University(English Edition)》 2007年第2期96-101,共6页
To deal with the nonlinear separable problem, the generalized noise clustering (GNC) algorithm is extended to a kernel generalized noise clustering (KGNC) model. Different from the fuzzy c-means (FCM) model and ... To deal with the nonlinear separable problem, the generalized noise clustering (GNC) algorithm is extended to a kernel generalized noise clustering (KGNC) model. Different from the fuzzy c-means (FCM) model and the GNC model which are based on Euclidean distance, the presented model is based on kernel-induced distance by using kernel method. By kernel method the input data are nonlinearly and implicitly mapped into a high-dimensional feature space, where the nonlinear pattern appears linear and the GNC algorithm is performed. It is unnecessary to calculate in high-dimensional feature space because the kernel function can do it just in input space. The effectiveness of the proposed algorithm is verified by experiments on three data sets. It is concluded that the KGNC algorithm has better clustering accuracy than FCM and GNC in clustering data sets containing noisy data. 展开更多
关键词 fuzzy clustering Pattern recognition Kernel methods Noise clustering Kernel generalized noise clustering
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Overlay Generalization of Polygons Based on Fuzzy-Voronoi
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作者 赵学胜 陈军 王金庄 《International Journal of Mining Science and Technology》 SCIE EI 2000年第2期15-20,共6页
The analysis of an overlaid map with different attributes has a very important function in GIS. In an overlaid map, approximately half of the constructed polygons are tiny and only account for less than 5% of the tota... The analysis of an overlaid map with different attributes has a very important function in GIS. In an overlaid map, approximately half of the constructed polygons are tiny and only account for less than 5% of the total area. In subsequent analysis of an overlaid map, a tiny polygon may require the same amount of computing time and memory space as any large one. In addition, in most cases it is meaningless to treat such polygons as distinct analysis units. So eliminating the tiny polygons is useful to improve efficiency. Now we often use the methods of “boundary comparison” and “fuzzy discriminance” to merge tiny polygons. But in the boundary comparison method, a polygon may be merged into a neighbor of quite different attribute values. In the second method, when the fuzzy grades of two boundary lines are almost the same and their lengths are different, this can lead to large error. In this paper, the partition principle of fuzzy Voronoi (F V) is proposed based on the characteristic of fuzzy boundary and the contiguity of Voronoi diagram. The bigger tiny polygons are divided by Voronoi diagram, and then are merged to neighbor polygon according to contiguity. The F V principle and arithmetic are presented in detail. In the end, an experiment is given; the result has proved that error in the F V method, compared with the two other methods, is only about 30%. 展开更多
关键词 fuzzy BOUNDARY fuzzy VORONOI OVERLAY generALIZATION
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基于模糊层次分析的致密气储层广义平面阻流带识别
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作者 赖枫鹏 李彬册 +1 位作者 任广磊 张伟 《中国海上油气》 北大核心 2025年第1期129-138,共10页
致密气储层具有物性条件差、非均质性强、含水饱和度高等特点,储层中存在流体渗流受限区域,使得气井产量和控制储量受到影响。一般意义上的阻流带强调的是沉积、成岩作用,以及砂体边界发育等静态地质因素对生产的影响,缺少气水两相渗流... 致密气储层具有物性条件差、非均质性强、含水饱和度高等特点,储层中存在流体渗流受限区域,使得气井产量和控制储量受到影响。一般意义上的阻流带强调的是沉积、成岩作用,以及砂体边界发育等静态地质因素对生产的影响,缺少气水两相渗流过程中不同因素产生的动态阻流表征。首先明确了致密气储层广义平面阻流带的内涵,提出了从生产特征、储层特征和两相共渗特征三个方面进行分析。基于模糊层次分析法,建立了广义平面阻流带层次结构模型和综合评价指标(GI),以鄂尔多斯盆地某致密气藏井区为例,计算了不同因素的影响权重值,得到GI数值,通过插值绘制了研究区广义平面阻流带发育图。进一步对比研究了高产、中产、低产三类井无量纲产气量和无量纲产量递减率与GI数值的关系,结果表明:无量纲产气量与GI值呈负相关关系,无量纲产量递减率与GI值呈正相关关系。利用广义平面阻流带发育图可以为后续气井工作制度的优化调整提供科学支撑。 展开更多
关键词 致密气 广义平面阻流带 评价指标 识别方法 模糊层次分析 权重计算
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NEW METHOD FOR MEASURING FUZZINESS IN ROUGH SETS 被引量:4
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作者 何亚群 胡寿松 魏崇辉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期31-35,共5页
A method with the fuzzy entropy for measuring fuzziness to fuzzy problem in rough sets is proposed. A new sort of the fuzzy entropy is given. The calculating formula and the equivalent expression method with the fuzzy... A method with the fuzzy entropy for measuring fuzziness to fuzzy problem in rough sets is proposed. A new sort of the fuzzy entropy is given. The calculating formula and the equivalent expression method with the fuzzy entropy in rough sets based on equivalence relation are provided, and the properties of the fuzzy entropy are proved. The fuzzy entropy based on equivalent relation is extended to generalize the fuzzy entropy based on general binary relation, and the calculating formula and the equivalent expression of the generalized fuzzy entropy are also given. Finally, an example illustrates the way for getting the fuzzy entropy. Results show that the fuzzy entropy can conveniently measure the fuzziness in rough sets. 展开更多
关键词 rough sets FUZZINESS fuzzy entropy generalized fuzzy entropy
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关于(λ,μ)-广义Fuzzy子环 被引量:19
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作者 廖祖华 李雪绫 +2 位作者 盛慧卿 黄昱 顾慧 《江南大学学报(自然科学版)》 CAS 2004年第6期622-624,共3页
在(λ,μ) 广义Fuzzy环的概念的基础上,进一步讨论它们的一些代数性质,得到了环的Fuzzy子集是(λ,μ) 广义Fuzzy子环的充分条件.
关键词 模糊代数 模糊子环 μ)-广义模糊子环
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广义Fuzzy子群的广义Fuzzy正规子群 被引量:2
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作者 曹姝 廖祖华 +1 位作者 刘春芝 胡淼菡 《江南大学学报(自然科学版)》 CAS 2010年第5期608-611,共4页
给出了广义模糊子群的广义模糊正规子群的定义,得到了它的一些等价条件和性质;另外,还获得了它的同态像与原像的相关性质。
关键词 模糊群 广义模糊子群 广义模糊正规子群 广义模糊子群的广义模糊正规子群
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诊断汽轮发电机组振动故障的一种Fuzzy聚类分析模型 被引量:7
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作者 陈孝国 张晓光 《煤炭技术》 CAS 2007年第4期9-11,共3页
首先运用基于传递闭包的模糊等价矩阵法对原始数据进行初始分类,得到了标准故障样本,然后将标准故障样本与待检样本一起作为分类样本,再用模糊ISODATA法求出最优分类矩阵和聚类中心,并依此来判断待检验样本的故障类型。实践证明,这种方... 首先运用基于传递闭包的模糊等价矩阵法对原始数据进行初始分类,得到了标准故障样本,然后将标准故障样本与待检样本一起作为分类样本,再用模糊ISODATA法求出最优分类矩阵和聚类中心,并依此来判断待检验样本的故障类型。实践证明,这种方法能够有效地诊断发电机组的振动故障。 展开更多
关键词 汽轮发电机组 故障诊断 模糊聚类分析
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L-Fuzzy集上(G)Fuzzy积分特性 被引量:2
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作者 宋士吉 哈明虎 吴从 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 1994年第3期1-6,共6页
给出TL-fuzzy集上(G)fuzzy积分的定义.讨论了这类广义fuzzy积分的基本特性,得到了积分转化定理及可积性充要条件,最后指出(G)fuzzy积分的两个收敛定理.
关键词 L模糊集 模糊积分 模糊数学
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关于Fuzzy正规子群的一个注记 被引量:2
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作者 刘龙章 杨志辉 《科技通报》 北大核心 2003年第3期215-216,共2页
深入地研究了Fuzzy正规子群和生成Fuzzy正规子群的若干性质,从而推广了文献[3,5]中的相应结果.
关键词 代数学 fuzzy正规子群 生成fuzzy子群
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模糊(Fuzzy)映象的广义补余问题 被引量:1
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作者 张石生 黄南京 《应用数学和力学》 EI CSCD 北大核心 1992年第8期667-675,共9页
本文引入一类关于模糊(Fuzzy)映象的新的广义补余问题,构造出一类新的迭代算法.我们讨论这类广义补余问题解的存在性及迭代序列的收敛性.
关键词 算法 广义补余问题 模糊映象
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基于fuzzy-PI双模控制的光伏发电系统最大功率点跟踪仿真研究 被引量:13
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作者 程启明 程尹曼 +1 位作者 倪仁杰 汪明媚 《太阳能学报》 EI CAS CSCD 北大核心 2011年第5期704-709,共6页
为了提高太阳电池阵列的工作效率和整个光伏发电系统的稳定性,在光伏发电系统中需要对光伏电池的最大功率点进行跟踪。为了消除常规模糊跟踪算法在最大功率点附近出现的振荡问题,在分析光伏电池伏安特性的基础上,提出了fuzzy-PI双模控... 为了提高太阳电池阵列的工作效率和整个光伏发电系统的稳定性,在光伏发电系统中需要对光伏电池的最大功率点进行跟踪。为了消除常规模糊跟踪算法在最大功率点附近出现的振荡问题,在分析光伏电池伏安特性的基础上,提出了fuzzy-PI双模控制策略,分析了该控制算法的原理,并对控制系统做了设计。Matlab/Simulink仿真表明fuzzy-PI双模控制能够快速、准确地跟踪最大功率点,避免了最大功率点处的振荡,提高了系统稳定性和能量转换效率,从而使整个双模控制兼有了MPPT精确性与快速性。 展开更多
关键词 最大功率点跟踪 光伏发电 占空比扰动法 fuzzy-PI双模控制 光伏阵列
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PID-Fuzzy分段式控制方法在太阳跟踪系统中的应用 被引量:1
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作者 卢秀和 李亚杰 王鹤 《江南大学学报(自然科学版)》 CAS 2010年第4期476-480,共5页
基于自动跟踪光伏发电系统,对太阳位置的检测和光电池云台跟踪控制的问题进行了深入的分析,并提出了PID-Fuzzy分段式跟踪控制方法。通过对太阳方位角的分析计算和电池板方位角的检测,设计了以太阳方位角为输入量、电池板方位角为反馈量... 基于自动跟踪光伏发电系统,对太阳位置的检测和光电池云台跟踪控制的问题进行了深入的分析,并提出了PID-Fuzzy分段式跟踪控制方法。通过对太阳方位角的分析计算和电池板方位角的检测,设计了以太阳方位角为输入量、电池板方位角为反馈量的PID-Fuzzy控制器。该控制器可以依据角度的偏差大小来自动切换控制规律,较好地解决了系统快速性和跟踪精度的问题。并且通过Matlab仿真和实验数据对该控制器性能进行了分析。结果表明,该方法不仅降低了调节时间,而且使控制跟踪精度在原有精度基础上提高了2%,有效地提高了光电转换效率,为同类跟踪系统提供了可行性方案。 展开更多
关键词 光伏发电 位置跟踪 方位角 PID-fuzzy控制 跟踪精度
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