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Covering-Based Soft Rough Sets 被引量:1
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作者 Jian-Guo Tang Kun She Yu-Qi Wang 《Journal of Electronic Science and Technology》 CAS 2011年第2期118-123,共6页
Covering-based rough sets process data organized by a covering of the universe. A soft set is a parameterized family of subsets of the universe. Both theories can deal with the uncertainties of data. Soft sets have no... Covering-based rough sets process data organized by a covering of the universe. A soft set is a parameterized family of subsets of the universe. Both theories can deal with the uncertainties of data. Soft sets have not any restrictions on the approximate description of the object,and they might form a covering of the universe. From this viewpoint,we establish a connection between these two theories. Specifically,we propose a complementary parameter for this purpose. With this parameter,the soft covering approximation space is established and the two theories are bridged. Furthermore,we study some relations between the covering and the soft covering approximation space and obtain some significant results. Finally,we define a notion of combine parameter which can help us to simplify the set of parameters and reduce the storage requirement of a soft covering approximation space. 展开更多
关键词 Complementary parameter covering-based rough sets covering-element soft set
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Study on covering rough sets with topological methods 被引量:1
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作者 Xue Wang Liwen Ma 《CAAI Transactions on Intelligence Technology》 2019年第3期129-134,共6页
The authors study the covering rough sets by topological methods. They combine the covering rough sets and topological spaces by means of defining some new types of spaces called covering rough topological (CRT) space... The authors study the covering rough sets by topological methods. They combine the covering rough sets and topological spaces by means of defining some new types of spaces called covering rough topological (CRT) spaces based on neighbourhoods or complementary neighbourhoods. As the separation axioms play a fundamental role in general topology, they introduce all these axioms into covering rough set theories and thoroughly study the equivalent conditions for every separation axiom in several CRT spaces. They also investigate the relationships between the separation axioms in these special spaces and reveal these relationships through diagrams in different CRT spaces. 展开更多
关键词 STUDY on covering rough sets TOPOLOGICAL methods different CRT SPACES
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Properties and Relations of Several Operators Based on Covering Rough Sets
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作者 夏秀云 田浩 秦克云 《Journal of Southwest Jiaotong University(English Edition)》 2010年第2期182-187,共6页
The coveting rough sets theory is a generalization of traditional rough set theory, and can also describe information with incompleteness and fuzziness in information systems. In this paper, we first provide the defin... The coveting rough sets theory is a generalization of traditional rough set theory, and can also describe information with incompleteness and fuzziness in information systems. In this paper, we first provide the definitions of several upper and lower covering approximation operators on the covering approximation space. Then, we study the properties of these operators. Finally, we propose the mutual relations between approximation operators and similar relations of the operator ( I ) based on the covering rough sets. 展开更多
关键词 rough sets covering rough sets covering approximation operators
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Numerical Characterizations of Covering Rough Sets Based on Evidence Theory
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作者 CHEN Degang ZHANG Xiao 《浙江海洋学院学报(自然科学版)》 CAS 2010年第5期416-419,共4页
Covering rough sets are improvements of traditional rough sets by considering cover of universe instead of partition.In this paper,we develop several measures based on evidence theory to characterize covering rough se... Covering rough sets are improvements of traditional rough sets by considering cover of universe instead of partition.In this paper,we develop several measures based on evidence theory to characterize covering rough sets.First,we present belief and plausibility functions in covering information systems and study their properties.With these measures we characterize lower and upper approximation operators and attribute reductions in covering information systems and decision systems respectively.With these discussions we propose a basic framework of numerical characterizations of covering rough sets. 展开更多
关键词 covering rough sets Attribute reduction Belief and plausibility functions Evidence theory
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Interval-Valued Intuitionistic Fuzzy-Rough Sets
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作者 WU Yan-hua LI Ke-dian 《浙江海洋学院学报(自然科学版)》 CAS 2010年第5期496-506,共11页
This paper combines interval-valued intuitionistic fuzzy sets and rough sets.It studies rougheness in interval-valued intuitionistic fuzzy sets and proposes one kind of interval-valued intuitionistic fuzzy-rough sets ... This paper combines interval-valued intuitionistic fuzzy sets and rough sets.It studies rougheness in interval-valued intuitionistic fuzzy sets and proposes one kind of interval-valued intuitionistic fuzzy-rough sets models under the equivalence relation in crisp sets.That extends the classical rough set defined by Pawlak. 展开更多
关键词 interval-valued intuitionistic fuzzy sets interval-valued intuitionistic fuzzy rough sets Hamming distance Approximation roughness
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Dualities in Covering Rough Operations 被引量:1
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作者 William Zhu 《南昌工程学院学报》 CAS 2006年第2期56-59,共4页
Rough set theory is a technique of granular computing. In this paper, we study a type of generalized rough sets based on covering. There are several literatures[1,40-43] exploring covering-based rough sets. Our focus ... Rough set theory is a technique of granular computing. In this paper, we study a type of generalized rough sets based on covering. There are several literatures[1,40-43] exploring covering-based rough sets. Our focus of this paper is on the dualities in rough operations. 展开更多
关键词 rough set covering granular computing DUALITY
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Synthetic security assessment for incomplete interval-valued information system 被引量:1
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作者 赵亮 Xue Zhi 《High Technology Letters》 EI CAS 2012年第2期160-166,共7页
In order to understand the security conditions of the incomplete interval-valued information system (IllS) and acquire the corresponding solution of security problems, this paper proposes a multi-attribute group dec... In order to understand the security conditions of the incomplete interval-valued information system (IllS) and acquire the corresponding solution of security problems, this paper proposes a multi-attribute group decision- making (MAGDM) security assessment method based on the technique for order performance by similarity to ideal solution (TOPSIS). For IllS with preference information, combining with dominance-based rough set approach (DRSA), the effect of incomplete interval-valued information on decision results is discussed. For the imprecise judgment matrices, the security attribute weight can be obtained using Gibbs sampling. A numerical example shows that the proposed method can acquire some valuable knowledge hidden in the incomplete interval-valued information. The effectiveness of the proposed method in the synthetic security assessment for IIIS is verified. 展开更多
关键词 security assessment incomplete interval-valued information system(IIIS) multi-attribute group decision-making(MAGDM) technique for order performance by similarity to ideal solution(TOPSIS) dominance- based rough set approach(DRSA) Gibbs sampling
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基于Rough集的交叉覆盖算法设计 被引量:2
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作者 吴涛 张铃 《计算机科学》 CSCD 北大核心 2003年第3期57-59,共3页
This paer gives an artificial network(RCSN)combining rough set theory and covering design algorithm,which reduces condition attribute using rough set theory and designs the structure of neural network with covering de... This paer gives an artificial network(RCSN)combining rough set theory and covering design algorithm,which reduces condition attribute using rough set theory and designs the structure of neural network with covering de-sign algorithm. An instance shows this kind of network has the advantages of fast computation and high accuracy ;themethod also can cut down the occupying of memory and the cost of data collecting. 展开更多
关键词 rough 交叉覆盖算法 设计 人工神经网络 粗糙集理论 人工智能
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基于Rough集和构造性学习神经网络的经济预警模型 被引量:3
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作者 朱勇 吴涛 《合肥工业大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第7期836-839,843,共5页
在深入分析人工神经网络(ANN)与粗集(Rough set)理论方法的基础上,将Rough集、构造性神经网络与宏观经济预警研究相结合,尝试建立起基于Rough集-覆盖算法的构造性神经网络宏观经济预警方法体系;结合安徽省经济数据,对该模型预警实证分... 在深入分析人工神经网络(ANN)与粗集(Rough set)理论方法的基础上,将Rough集、构造性神经网络与宏观经济预警研究相结合,尝试建立起基于Rough集-覆盖算法的构造性神经网络宏观经济预警方法体系;结合安徽省经济数据,对该模型预警实证分析。理论和实践证明,基于Rough集-覆盖算法的构造性神经网络预警模型是有效的、可行的,且具有较高的精度,从而为动态经济预警提供一条新的途经。 展开更多
关键词 经济预警 构造性学习 覆盖算法 粗糙集
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覆盖广义Rough集中的隶属关系 被引量:1
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作者 刘邱云 付雪峰 吴根秀 《南昌大学学报(理科版)》 CAS 北大核心 2006年第3期227-229,共3页
对覆盖广义Rough集中的隶属关系、隶属函数进行了定义,并利用隶属函数定义了集合的Rough包含与Rough相等,得到一些与Paw lak的Rough集不同的性质。
关键词 rough 隶属关系 隶属函数
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Knowledge modeling based on interval-valued fuzzy rough set and similarity inference: prediction of welding distortion 被引量:5
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作者 Zhi-qiang FENG Cun-gen LIU Hu HUANG 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2014年第8期636-650,共15页
Knowledge-based modeling is a trend in complex system modeling technology. To extract the process knowledge from an information system, an approach of knowledge modeling based on interval-valued fuzzy rough set is pre... Knowledge-based modeling is a trend in complex system modeling technology. To extract the process knowledge from an information system, an approach of knowledge modeling based on interval-valued fuzzy rough set is presented in this paper, in which attribute reduction is a key to obtain the simplified knowledge model. Through defining dependency and inclusion functions, algorithms for attribute reduction and rule extraction are obtained. The approximation inference plays an important role in the development of the fuzzy system. To improve the inference mechanism, we provide a method of similaritybased inference in an interval-valued fuzzy environment. Combining the conventional compositional rule of inference with similarity based approximate reasoning, an inference result is deduced via rule translation, similarity matching, relation modification, and projection operation. This approach is applied to the problem of predicting welding distortion in marine structures, and the experimental results validate the effectiveness of the proposed methods of knowledge modeling and similarity-based inference. 展开更多
关键词 Knowledge modeling interval-valued fuzzy rough set Similarity-based inference Welding distortion prediction
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覆盖Rough集及其隶属函数
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作者 邓大勇 黄田耕 刘清 《南昌水专学报》 CAS 2002年第2期7-10,共4页
从覆盖的角度重新定义了Rough集,并用一种新的、从邻域的角度重新定义了隶属函数,得到了与Pawlak与Rough集隶属函数的一些不同的性质,而且隶属函数的意义也与Pawlak的Rough集隶属函数的意义有所不同.
关键词 覆盖 rough 隶属函数
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完备格上的广义Rough集模型
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作者 姚刚 张小红 《宁波大学学报(理工版)》 CAS 2007年第2期197-201,共5页
基于way-below关系和弱way-below关系,在具有逆合对应的完备格上建立了广义Rough上下近似算子,研究了它们的基本性质,并说明本文提出的广义Rough集模型是Pawlak标准粗糙集的推广.同时,在De Morgan代数上建立了广义Rough上下近似算子,给... 基于way-below关系和弱way-below关系,在具有逆合对应的完备格上建立了广义Rough上下近似算子,研究了它们的基本性质,并说明本文提出的广义Rough集模型是Pawlak标准粗糙集的推广.同时,在De Morgan代数上建立了广义Rough上下近似算子,给出了相应的基本性质. 展开更多
关键词 rough WAY-BELOW关系 弱way-below关系 完备格 覆盖 约简
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基于集覆盖理论的覆盖信息系统属性约简方法
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作者 徐晔 许晴媛 李进金 《郑州大学学报(理学版)》 CAS 北大核心 2024年第1期60-67,共8页
针对覆盖信息系统属性约简问题,提出基于集覆盖理论的覆盖信息系统属性约简方法。首先,构造覆盖信息系统的相关矩阵,通过相关矩阵诱导出覆盖信息系统的集覆盖模型,并探讨了覆盖信息系统与其诱导的集覆盖模型之间的联系,发现集覆盖模型... 针对覆盖信息系统属性约简问题,提出基于集覆盖理论的覆盖信息系统属性约简方法。首先,构造覆盖信息系统的相关矩阵,通过相关矩阵诱导出覆盖信息系统的集覆盖模型,并探讨了覆盖信息系统与其诱导的集覆盖模型之间的联系,发现集覆盖模型的一个极小覆盖恰是原覆盖信息系统的一个属性约简集,从而可以将求解覆盖信息系统的属性约简问题转化为求解对应集覆盖模型的极小集覆盖问题。其次,利用集覆盖启发式算法(set covering heuristic algorithm,SCHA)在解决集覆盖问题上具有更高的精度和更好的性能,给出了基于SCHA的覆盖信息系统属性约简的求解步骤及算法。最后,通过实例验证了所提方法的可行性和有效性。 展开更多
关键词 集覆盖 覆盖信息系统 集覆盖启发式算法 属性约简 粗糙集
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基于覆盖的粗糙模糊集模型研究 被引量:31
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作者 魏莱 苗夺谦 +1 位作者 徐菲菲 夏富春 《计算机研究与发展》 EI CSCD 北大核心 2006年第10期1719-1723,共5页
在研究覆盖粗糙集模型中,发现对覆盖粗糙集上近似的定义并不一致.简述了各个模型的区别,并在一个较合理的覆盖粗糙集上近似定义上,结合覆盖约简理论,重新定义了基于覆盖的粗糙集模型,讨论了它的一些性质.另外,将模型进行推广,定义了基... 在研究覆盖粗糙集模型中,发现对覆盖粗糙集上近似的定义并不一致.简述了各个模型的区别,并在一个较合理的覆盖粗糙集上近似定义上,结合覆盖约简理论,重新定义了基于覆盖的粗糙集模型,讨论了它的一些性质.另外,将模型进行推广,定义了基于覆盖的粗糙模糊集模型,证明了它具有一些较好的性质. 展开更多
关键词 覆盖 覆盖约简 粗糙集 粗糙模糊集
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一种覆盖粗糙模糊集模型 被引量:39
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作者 胡军 王国胤 张清华 《软件学报》 EI CSCD 北大核心 2010年第5期968-977,共10页
粗糙集扩展模型的研究是粗糙集理论研究的一个重要问题.其中,基于覆盖的粗糙集模型扩展是粗糙集扩展模型中的重要一类.覆盖近似空间中的概念近似是从覆盖近似空间中获取知识的关键.目前,研究者对覆盖近似空间中经典集合的近似进行了较... 粗糙集扩展模型的研究是粗糙集理论研究的一个重要问题.其中,基于覆盖的粗糙集模型扩展是粗糙集扩展模型中的重要一类.覆盖近似空间中的概念近似是从覆盖近似空间中获取知识的关键.目前,研究者对覆盖近似空间中经典集合的近似进行了较多的研究.针对覆盖近似空间中模糊集合的近似,虽然不同的覆盖粗糙模糊集模型被提了出来,但它们都存在不合理性.从规则的置信度出发,提出了一种新的覆盖粗糙模糊集模型.该模型修正了已有模型中存在对象在下近似中不确定可分和上近似中不近似可分的问题.分析了具有偏序关系的两个覆盖近似空间中上、下近似之间的关系,发现两个不同覆盖生成相同覆盖粗糙模糊集的充要条件是这两个覆盖的约简恒等.分析了新模型与Wei模型、Xu模型之间的关系,发现这两种模型是新模型的两种极端情况,且其应用前提是覆盖为一元覆盖.这些结论将为覆盖粗糙模糊集模型应用于决策为模糊的情形提供理论基础. 展开更多
关键词 覆盖近似空间 粗糙集 模糊集 粗糙模糊集 置信度
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基于覆盖的粗糙模糊集的粗糙熵 被引量:13
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作者 徐菲菲 苗夺谦 +1 位作者 李道国 魏莱 《计算机科学》 CSCD 北大核心 2006年第10期179-181,共3页
覆盖约简是研究覆盖去冗余问题的一种有效方法。本文在基于最简覆盖的粗糙集模型的基础上,将粗糙度和粗糙熵的概念引入基于最简覆盖的粗糙模糊集,用来度量其不确定性程度;讨论了它们的一些性质,并通过实例说明粗糙熵比粗糙度更能精确地... 覆盖约简是研究覆盖去冗余问题的一种有效方法。本文在基于最简覆盖的粗糙集模型的基础上,将粗糙度和粗糙熵的概念引入基于最简覆盖的粗糙模糊集,用来度量其不确定性程度;讨论了它们的一些性质,并通过实例说明粗糙熵比粗糙度更能精确地反映基于最简覆盖的粗糙模糊集的不确定性程度。 展开更多
关键词 粗糙模糊集 最简覆盖 粗糙度 粗糙熵
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覆盖粗糙集的公理化 被引量:21
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作者 杨勇 朱晓钟 李廉 《计算机科学》 CSCD 北大核心 2009年第5期181-182,共2页
粗糙集的公理系统是粗糙集理论与应用的基础。覆盖粗糙集是粗糙集理论的自然的有意义的推广。基于Xu等提出的新的覆盖粗糙集模型,研究了新模型的公理系统,用4条简洁且相互独立的公理刻画了覆盖粗糙集。这些研究有助于覆盖粗糙集理论研... 粗糙集的公理系统是粗糙集理论与应用的基础。覆盖粗糙集是粗糙集理论的自然的有意义的推广。基于Xu等提出的新的覆盖粗糙集模型,研究了新模型的公理系统,用4条简洁且相互独立的公理刻画了覆盖粗糙集。这些研究有助于覆盖粗糙集理论研究的深入和完善。 展开更多
关键词 粗集 覆盖粗集 公理
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变精度覆盖粗糙集 被引量:17
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作者 刘瑞新 孙士保 秦克云 《计算机工程与应用》 CSCD 北大核心 2008年第12期47-50,共4页
介绍了Ziarko变精度粗糙集模型和覆盖粗糙集模型;定义了多数包含关系;借助引入的误差参数β(0≤β<0.5),给出了基于对象邻域的变精度覆盖粗糙集模型中β上近似、β下近似、β边界和β负域的定义以及β近似质量和β粗糙性测度定义;详... 介绍了Ziarko变精度粗糙集模型和覆盖粗糙集模型;定义了多数包含关系;借助引入的误差参数β(0≤β<0.5),给出了基于对象邻域的变精度覆盖粗糙集模型中β上近似、β下近似、β边界和β负域的定义以及β近似质量和β粗糙性测度定义;详细讨论了β上、下近似算子的性质、集合的相对可辨别性、该模型与Ziarko变精度粗糙集模型和覆盖粗糙集模型的关系;最后探讨了变精度覆盖粗糙集模型中的约简问题并在所给模型的基础上举例说明了它们在信息处理中的应用。 展开更多
关键词 覆盖 近似空间 邻域 变精度覆盖粗糙集模型
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覆盖广义粗糙集的模糊性 被引量:19
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作者 徐伟华 张文修 《模糊系统与数学》 CSCD 北大核心 2006年第6期115-121,共7页
在研究覆盖广义粗糙集的基础上,利用两个距离函数Hamming和Euclidean距离函数,结合模糊集的最近寻常集,引入了覆盖广义粗糙集模糊度的概念,给出了一种模糊度计算方法,并证明了该模糊度的一些重要性质。这些结果在覆盖广义粗糙集的理论... 在研究覆盖广义粗糙集的基础上,利用两个距离函数Hamming和Euclidean距离函数,结合模糊集的最近寻常集,引入了覆盖广义粗糙集模糊度的概念,给出了一种模糊度计算方法,并证明了该模糊度的一些重要性质。这些结果在覆盖广义粗糙集的理论研究和应用都发挥着一定作用。 展开更多
关键词 模糊集 最近寻常集 模糊性指数 粗糙集 覆盖广义粗糙集 覆盖广义粗糙集的模糊性
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