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S-粗集和它的一般结构 被引量:174
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作者 史开泉 崔玉泉 《山东大学学报(理学版)》 CAS CSCD 北大核心 2002年第6期471-474,共4页
给出论域U上元素迁移F ,F ,单向奇异集合 ,双向奇异集合的概念 ;利用这些概念 ,提出奇异粗集 ,简称S 粗集 ,给出S 粗集的数学结构 ,S 粗集的存在背景和意义解释 .S 粗集包含两种结构 :单向S 粗集 ,双向S 粗集 ;S 粗集是研究系统动态近... 给出论域U上元素迁移F ,F ,单向奇异集合 ,双向奇异集合的概念 ;利用这些概念 ,提出奇异粗集 ,简称S 粗集 ,给出S 粗集的数学结构 ,S 粗集的存在背景和意义解释 .S 粗集包含两种结构 :单向S 粗集 ,双向S 粗集 ;S 粗集是研究系统动态近似特性 ,知识挖掘 ,知识发现的一个新的理论工具 . 展开更多
关键词 S-集合 S-粗集 S-粗结构 迁移平衡定理 外迁移淹没定理 内迁移淹没定理
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Reduction Algorithms Based on Discernibility Matrix:The Ordered Attributes Method 被引量:130
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作者 王珏 王驹 《Journal of Computer Science & Technology》 SCIE EI CSCD 2001年第6期489-504,共16页
In this paper, we present reduction algorithms based on the principle of Skowron's discernibility matrix - the ordered attributes method. The completeness of the algorithms for Pawlak reduct and the uniqueness for... In this paper, we present reduction algorithms based on the principle of Skowron's discernibility matrix - the ordered attributes method. The completeness of the algorithms for Pawlak reduct and the uniqueness for a given order of the attributes are proved. Since a discernibility matrix requires the size of the memory of U2, U is a universe of objects, it would be impossible to apply these algorithms directly to a massive object set. In order to solve the problem, a so-called quasi-discernibility matrix and two reduction algorithms are proposed. Although the proposed algorithms are incomplete for Pawlak reduct, their opimal paradigms ensure the completeness as long as they satisfy some conditions. Finally we consider the problem on the reduction of distributive object sets. 展开更多
关键词 rough set theory principle of discernibility matrix inductive machine learning
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Extension theory and its application 被引量:131
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作者 CAI WenResearch Institute of Matter-Element Analysis , Guangdong University of Technology , Guangzhou 510090, China 《Chinese Science Bulletin》 SCIE EI CAS 1999年第17期1538-1548,共11页
The article Extension Set and Non-compatible Problems was published in 1983. It proclaimed the birth of extension theory. Its objects of study are contradictory problems in the realistic world; its theoretical pillars... The article Extension Set and Non-compatible Problems was published in 1983. It proclaimed the birth of extension theory. Its objects of study are contradictory problems in the realistic world; its theoretical pillars are matter element theory and extension set theory. Its basic methods are extension methods. Its practical methods are extension engineering methods, 展开更多
关键词 EXTENSION THEORY MATTER ELEMENT EXTENSION set.
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Sugar Input, Metabolism, and Signaling Mediated by Invertase: Roles in Development, Yield Potential, and Response to Drought and Heat 被引量:106
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作者 Yong-Ling Ruan Ye Jin +2 位作者 Yue-Jian Yang Guo-Jing Li John S. Boyer 《Molecular Plant》 SCIE CAS CSCD 2010年第6期942-955,共14页
Invertase (INV) hydrolyzes sucrose into glucose and fructose, thereby playing key roles in primary metabolism and plant development. Based on their pH optima and sub-cellular locations, INVs are categorized into cel... Invertase (INV) hydrolyzes sucrose into glucose and fructose, thereby playing key roles in primary metabolism and plant development. Based on their pH optima and sub-cellular locations, INVs are categorized into cell wall, cytoplasmic, and vacuolar subgroups, abbreviated as CWlN, CIN, and VlN, respectively. The broad importance and implications of INVs in plant development and crop productivity have attracted enormous interest to examine INV function and regulation from multiple perspectives. Here, we review some exciting advances in this area over the last two decades, focusing on (1) new or emerging roles of INV in plant development and regulation at the post-translational level through interaction with inhibitors, (2) cross-talk between INV-mediated sugar signaling and hormonal control of development, and (3) sugar- and INV-mediated responses to drought and heat stresses and their impact on seed and fruit set. Finally, we discuss major questions arising from this new progress and outline future directions for unraveling mechanisms underlying INV-mediated plant development and their potential applications in plant biotechnology and agriculture. 展开更多
关键词 Crop yield DROUGHT heat stress INVERTASE reproductive development seed and fruit set sugar metabolism sugar signaling.
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分段随机抽选法在智能组卷中的研究与应用 被引量:41
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作者 金汉均 郑世珏 吴明武 《计算机应用研究》 CSCD 北大核心 2003年第9期102-103,126,共3页
在智能组卷方案中,提出一种新的"分段随机抽选法",并用该算法与传统的组卷算法在生成试卷的效率上进行了比较,同时针对由本算法所引起的修改操作困难提出了解决方法。该系统是在Win dows环境下,使用BorlandDelphi6.0,采用ADO... 在智能组卷方案中,提出一种新的"分段随机抽选法",并用该算法与传统的组卷算法在生成试卷的效率上进行了比较,同时针对由本算法所引起的修改操作困难提出了解决方法。该系统是在Win dows环境下,使用BorlandDelphi6.0,采用ADO数据存取技术访问MicrosoftAccess数据库实现的。 展开更多
关键词 分段随机抽选法 智能组卷 候选码 集合 ADO
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资产价格波动与宏观经济政策困境 被引量:51
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作者 瞿强 《管理世界》 CSSCI 北大核心 2007年第10期139-149,共11页
本文系统评述目前宏观经济政策如何应对资产价格波动的有关研究,介绍这一领域中存在的主要争论,讨论未来的研究方向。论文首先在物价稳定与金融体系稳定的矛盾冲突中,引入有关资产价格波动与货币政策目标之间的一些争论;然后比较关于货... 本文系统评述目前宏观经济政策如何应对资产价格波动的有关研究,介绍这一领域中存在的主要争论,讨论未来的研究方向。论文首先在物价稳定与金融体系稳定的矛盾冲突中,引入有关资产价格波动与货币政策目标之间的一些争论;然后比较关于货币政策是否需要干预资产价格的两种不同的看法;接着进一步从货币政策目标、传导机制、资产价格的实际后果等方面分析上述政策争论背后的若干理论观点与实际困难;最后着重从金融监管的角度总结目前政策与学术界较为一致的看法,以及若干值得深入研究的问题。 展开更多
关键词 资产价格(As set PRICE s) 泡沫(Bubbles) 宏观经济政策(Macroeconomic Policies)
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Analysis on Attribute Reduction Strategies of Rough Set 被引量:47
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作者 王珏 苗夺谦 《Journal of Computer Science & Technology》 SCIE EI CSCD 1998年第2期189-192,F003,共5页
Several strategies for the minimal attribute reduction with polynomial time complexity (O(nk)) have been developed in rough set theory. Are they complete? While investigating the attribute reduction strategy based on ... Several strategies for the minimal attribute reduction with polynomial time complexity (O(nk)) have been developed in rough set theory. Are they complete? While investigating the attribute reduction strategy based on the discernibility matrix (DM),a counterexample is constructed theoretically, which demonstrates that these strategies are all incomplete with respect to the minimal reduction. 展开更多
关键词 Rough set minimal attribute reduction
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A new approach to water resources system assessment——set pair analysis method 被引量:44
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作者 WANG WenSheng JIN JuLiang +1 位作者 DING Jing LI YueQing 《Science China(Technological Sciences)》 SCIE EI CAS 2009年第10期3017-3023,共7页
Most traditional assessment methods, which have complicated mathematic formulas, are difficult for calculation and application in water resources system assessment. A new approach to water resources system assessment,... Most traditional assessment methods, which have complicated mathematic formulas, are difficult for calculation and application in water resources system assessment. A new approach to water resources system assessment, the set pair analysis method (SPAM), has been proposed based on the principle of set pair analysis (SPA). The basic ideals and steps of SPAM are discussed. The proposed method can take fuzzy property of threshold values for grade standards into full account and avoid determining the discrepancy uncertainty coefficient i or i1, i2, i3, … in SPA. The presented method is simple in concept, convenient to calculate and feasible for application. Two case studies of water resources assessment have been made. The results show that the proposed method is satisfactory. 展开更多
关键词 water RESOURCES ASSESSMENT set PAIR analysis CONNECTION DEGREE
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Multi-attribute decision making method for air target threat evaluation based on intuitionistic fuzzy sets 被引量:43
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作者 Yongjie XU YongchunWang Xudong Miu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第6期891-897,共7页
The function of the air target threat evaluation (TE) is the foundation for weapons allocation and senor resources management within the surface air defense. The multi-attribute evaluation methodology is utilized to... The function of the air target threat evaluation (TE) is the foundation for weapons allocation and senor resources management within the surface air defense. The multi-attribute evaluation methodology is utilized to address the issue of the TE in which the tactic features of the detected target are treated as evaluation attributes. Meanwhile, the intuitionistic fuzzy set (IFS) is employed to deal with information uncertainty in the TE process. Furthermore, on the basis of the entropy weight and inclusion-comparison probability, a hybrid TE method is developed. In order to accommodate the demands of naturalistic decision making, the proposed method allows air defense commanders to express their intuitive opinions besides incorporating into the threat features of the detected target. An illustrative example is provided to indicate the feasibility and advantage of the proposed method. 展开更多
关键词 threat evaluation (TE) intuitionistic fuzzy set (IFS) multi-attribute evaluation intuitive opinions entropy weight inclusion-comparison probability (ICP).
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Information granules and entropy theory in information systems 被引量:41
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作者 LIANG JiYe & QIAN YuHua Key Laboratory of Computational Intelligence and Chinese Information Processing,Ministry of Education School of Computer & Information Technology,Shanxi University,Taiyuan 030006,China 《Science in China(Series F)》 2008年第10期1427-1444,共18页
Information granulation and entropy theory are two main approaches to research uncertainty of an information system, which have been widely applied in many practical issues. In this paper, the characterizations and re... Information granulation and entropy theory are two main approaches to research uncertainty of an information system, which have been widely applied in many practical issues. In this paper, the characterizations and representations of information granules under various binary relations are investigated in information systems, an axiom definition of information granulation is presented, and some existing definitions of information granulation become its special forms. Entropy theory in information systems is further developed and the granulation monotonicity of each of them is proved. Moreover, the complement relationship between information granulation and entropy is established. This investigation unifies the results of measures for uncertainties in complete information systems and incomplete information systems. 展开更多
关键词 information systems information granule information granulation ENTROPY rough set
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电子商务中在线支付的安全保障 被引量:20
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作者 刘卫宁 宋伟 《计算机应用》 CSCD 1999年第7期3-6,共4页
本文详细分析和比较了保障在线支付安全的主流协议:SSL协议和SET协议。
关键词 在线支付 安全 SSL set 电子商务 INTERNET网
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A new algorithm of edge detection for color image: Generalized fuzzy operator 被引量:29
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作者 陈武凡 鲁贤庆 +1 位作者 陈建军 吴国雄 《Science China Mathematics》 SCIE 1995年第10期1272-1280,共9页
The definition of the generalized fuzzy set is presented for the first time, and a generalized fuzzy operator is proposed to transform a generalized fuzzy set into a normal fuzzy set. The algorithm theory of the opera... The definition of the generalized fuzzy set is presented for the first time, and a generalized fuzzy operator is proposed to transform a generalized fuzzy set into a normal fuzzy set. The algorithm theory of the operator, as the newest method of the edge detection of a 2-D image, is successfully established. Many experiments haw proved that the algorithm is simpler, more rapid and more precise in location than other edge detection methods. And a schedule of the concrete performance has been given additionally about the edge detection of color images. 展开更多
关键词 COLOR image edge detection GENERALIZED fuzzy OPERATOR GENERALIZED property set.
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中介真值程度的度量及其应用(Ⅱ) 被引量:33
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作者 洪龙 肖奚安 朱梧槚 《计算机学报》 EI CSCD 北大核心 2007年第9期1551-1558,共8页
结合中介逻辑中的模糊否定词和真值程度词的语义,论述了研究中介真值程度的度量对于应用的必要性;在对个体研究的基础之上,从离散型和连续型两个方面讨论了集合的真值程度的度量;在建立中介标准度后,提出模糊程度概念,提出中介熵定义,... 结合中介逻辑中的模糊否定词和真值程度词的语义,论述了研究中介真值程度的度量对于应用的必要性;在对个体研究的基础之上,从离散型和连续型两个方面讨论了集合的真值程度的度量;在建立中介标准度后,提出模糊程度概念,提出中介熵定义,并讨论了中介熵的最大值.针对反对对立强调两个概念之间存在"最大的差异",提出弱化"两极",突出"过渡"的观点.在对过渡与对立进行了一般性讨论后,建立了标准数值化映射和广义数值化映射概念,构造性地证明了过渡情形能转换为反对对立情形的充分条件.这表明在处理工程实践和科学研究中的模糊现象时,可以把所有存在过渡的情形作为反对对立处理,从而使中介真值程度的度量可以在更加广阔的领域得到应用. 展开更多
关键词 真值程度 集合 度量 模糊程度 中介熵 过渡
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木材变定的产生、回复及其永久固定 被引量:27
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作者 王洁瑛 赵广杰 《北京林业大学学报》 CAS CSCD 北大核心 1999年第3期71-77,共7页
在分子水平上解释木材变定的产生、回复及永久固定的机理对于丰富和完善木材流变学理论,开发新的木材加工技术等具有重要意义.该文较详细地归纳了关于木材变定的产生、回复以及永久固定的几个主要观点,为进一步弄清楚木材变定的永久... 在分子水平上解释木材变定的产生、回复及永久固定的机理对于丰富和完善木材流变学理论,开发新的木材加工技术等具有重要意义.该文较详细地归纳了关于木材变定的产生、回复以及永久固定的几个主要观点,为进一步弄清楚木材变定的永久固定机理提出了作者的几点看法. 展开更多
关键词 木材 变定 回复 永久固定
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竹节纱工艺设计及产品开发 被引量:24
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作者 顾宪祥 周秀玲 《棉纺织技术》 CAS CSCD 北大核心 2003年第4期35-37,共3页
在FA5 0 6型和FA5 0 2型细纱机上分别加装国产ZJ型和YTC83型竹节纱装置 ,开发生产了C 2 7 8tex、C 18tex、R/C 14 5tex及Modal 13tex竹节纱等品种 ,供喷气、剑杆织机织竹节布用。通过合理设计竹节周期、捻度、竹节长度、粗度和竹节密... 在FA5 0 6型和FA5 0 2型细纱机上分别加装国产ZJ型和YTC83型竹节纱装置 ,开发生产了C 2 7 8tex、C 18tex、R/C 14 5tex及Modal 13tex竹节纱等品种 ,供喷气、剑杆织机织竹节布用。通过合理设计竹节周期、捻度、竹节长度、粗度和竹节密度等工艺 ,使布面风格多样化。该项改造节约了设备投资 ,提高了产品的市场竞争力。 展开更多
关键词 竹节纱装置 工艺设计 产品开发 细纱机 改造 竹节花式纱
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太极拳运动对心率的影响 被引量:24
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作者 王玉林 周红萍 《中国体育科技》 北大核心 2000年第2期42-44,共3页
本人根据受试者在练习太极拳中的心率变化特点 ,以及测试其学练太极拳 5个月前后、两次安静状态下的相关心脏功能指标的变化 ,得出以下结论 :1 )现在普及推广的太极拳套路 ,其每套动作的完成时间最好在 5 min~ 6m in3 0 s;2 )每次至少... 本人根据受试者在练习太极拳中的心率变化特点 ,以及测试其学练太极拳 5个月前后、两次安静状态下的相关心脏功能指标的变化 ,得出以下结论 :1 )现在普及推广的太极拳套路 ,其每套动作的完成时间最好在 5 min~ 6m in3 0 s;2 )每次至少持续地重复 3遍套路练习 ,时间不少于 2 0 min;3 )练习者运动时的心率值最好在 1 2 0~ 1 3 0次 / m 展开更多
关键词 太极拳 套路 心率 健身 效果 运动时间 运动量
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On similarity measures of interval-valued intuitionistic fuzzy sets and their application to pattern recognitions 被引量:28
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作者 徐泽水 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期139-143,共5页
The concept of the degree of similarity between interval-valued intuitionistic fuzzy sets (IVIFSs) is introduced, and some distance measures between IVIFSs are defined based on the Hamming distance, the normalized H... The concept of the degree of similarity between interval-valued intuitionistic fuzzy sets (IVIFSs) is introduced, and some distance measures between IVIFSs are defined based on the Hamming distance, the normalized Hamming distance, the weighted Hamming distance, the Euclidean distance, the normalized Euclidean distance, and the weighted Euclidean distance, etc. Then, by combining the Hausdorff metric with the Hamming distance, the Euclidean distance and their weighted versions, two other similarity measures between IVIFSs, i. e., the weighted Hamming distance based on the Hausdorff metric and the weighted Euclidean distance based on the Hausdorff metric, are defined, and then some of their properties are studied. Finally, based on these distance measures, some similarity measures between IVIFSs are defined, and the similarity measures are applied to pattern recognitions with interval-valued intuitionistic fuzzy information. 展开更多
关键词 interval-valued intuitionistic fuzzy set SIMILARITY pattern recognition
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Some dimensional results for homogeneous Moran sets 被引量:24
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作者 丰德军 文志英 吴军 《Science China Mathematics》 SCIE 1997年第5期475-482,共8页
Let M({nk}k≥1,{ck}k≥1) be the collection of homogeneous Moran sets determined by {nk}k≥1and {ck}k≥1, where {nk}k≥1 is a sequence of positive integers and {ck}k≥1 a sequence of positive numbers. Then the maximal ... Let M({nk}k≥1,{ck}k≥1) be the collection of homogeneous Moran sets determined by {nk}k≥1and {ck}k≥1, where {nk}k≥1 is a sequence of positive integers and {ck}k≥1 a sequence of positive numbers. Then the maximal and minimal values of Hausdorff dimensions for elements in M are determined. The result is proved that for any value s between the maximal and minimal values, there exists an element in M{nk}k≥1, {ck}k≥1) such that its Hausdorff dimension is equal to s. The same results hold for packing dimension. In the meantime, some other properties of homogeneous Moran sets are discussed. 展开更多
关键词 HOMOGENEOUS MORAN set HOMOGENEOUS CANTOR set partial HOMOGENEOUS CANTOR set HAUSDORFF di-mension packing dimension.
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The necessary and sufficient conditions for returns to scale properties in generalized data envelopment analysis model 被引量:21
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作者 魏权龄 于刚 陆剑受 《Science China(Technological Sciences)》 SCIE EI CAS 2002年第5期503-517,共15页
We give definitions on increasing, constant and decreasing returns to scale under the generalized data envelopment analysis (GDEA) model. The GDEA model prossesses cone structures for describing evaluators’ preferenc... We give definitions on increasing, constant and decreasing returns to scale under the generalized data envelopment analysis (GDEA) model. The GDEA model prossesses cone structures for describing evaluators’ preferences toward different decision making units (DMU) and toward different input / output categories. The GDEA model contains many important DEA models as its subclasses. Based upon the definition, we discuss and rigorously prove the necessary and sufficient conditions for a DMU to have increasing, constant and decreasing returns to scale under a GDEA model, and discuss and clarify the differences and relationships of these conditions under different subclasses of the GDEA model. Furthermore, we describe a method based on a two-stage linear program to test returns to scale properties. 展开更多
关键词 data envelopment analysis efficient frontier multiple input/output DECISION making production POSSIBILITY set returns to scale.
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On the new results of global attractive set and positive invariant set of the Lorenz chaotic system and the applications to chaos control and synchronization 被引量:23
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作者 LIAO Xiaoxin 1, 2, 3 , FU Yuli 4 & XIE Shengli 4 1. Department of Control Science & Control Engineering, Huazhong University of Science & Technology, Wuhan 430074, China 2. School of Automation, Wuhan University of Science & Technology, Wuhan 430070, China +1 位作者 3. School of Information, Central South University of Economy, Politics and Law, Wuhan 430064, China 4. School of Electronics & Information Engineering, South China University of Technology, Guangzhou 510640, China Correspondence should be addressed to Liao Xiaoxin (email: xiaoxin_liao@hotmail.com) 《Science in China(Series F)》 2005年第3期304-321,共18页
Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies ... Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies the complex proofs of the two famous estimations presented by the Russian scholar Leonov. Our uniform formula can derive a series of the new estimations. Employing the idea of intersection in set theory, we extract a new Leonov formula-like estimation from the family of the estimations. With our method and the new estimation, one can confirm that there are no equilibrium, periodic solutions, almost periodic motions, wandering motions or other chaotic attractors outside the global attractive set. The Lorenz butterfly-like singular attractors are located in the global attractive set only. This result is applied to the chaos control and chaos synchronization. Some feedback control laws are obtained to guarantee that all the trajectories of the Lorenz systems track a periodic solution, or globally stabilize an unstable (or locally stable but not globally asymptotically stable) equilibrium. Further, some new global exponential chaos synchronization results are presented. Our new method and the new results are expected to be applied in real secure communication systems. 展开更多
关键词 Lorenz chaotic system global attractive set positive invariant set globally exponential tracking globally exponential synchronization.
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