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Rough function model and rough membership function 被引量:1
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作者 Wang Yun Guan Yanyong Huang Zhiqin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期522-528,共7页
Two pairs of approximation operators, which are the scale lower and upper approximations as well as the real line lower and upper approximations, are defined. Their properties and antithesis characteristics are analyz... Two pairs of approximation operators, which are the scale lower and upper approximations as well as the real line lower and upper approximations, are defined. Their properties and antithesis characteristics are analyzed. The rough function model is generalized based on rough set theory, and the scheme of rough function theory is made more distinct and complete. Therefore, the transformation of the real function analysis from real line to scale is achieved. A series of basic concepts in rough function model including rough numbers, rough intervals, and rough membership functions are defined in the new scheme of the rough function model. Operating properties of rough intervals similar to rough sets are obtained. The relationship of rough inclusion and rough equality of rough intervals is defined by two kinds of tools, known as the lower (upper) approximation operator in real numbers domain and rough membership functions. Their relative properties are analyzed and proved strictly, which provides necessary theoretical foundation and technical support for the further discussion of properties and practical application of the rough function model. 展开更多
关键词 rough set theory rough function model indiscernibility relation rough membership function roughnumber rough interval.
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Function S-Rough sets and its applications 被引量:25
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作者 Cui Yuquan Shi Kaiquan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期331-338,共8页
Based on S-rough sets(singular rough sets), this paper presents function S-rough sets (function singular rough sets)and its mathematical structures and features. Function S-rough sets has two forms: function one ... Based on S-rough sets(singular rough sets), this paper presents function S-rough sets (function singular rough sets)and its mathematical structures and features. Function S-rough sets has two forms: function one direction S-rough sets (function one direction singular rough sets) and function two direction S-rough sets (function two direction singular rough sets). This paper advances the relationship theorem of function S-rough sets and S-rough sets. Function S-rough sets is the general form of S-rough sets, and S-rough sets is the special ease of function S-rough sets. In this paper, applications of function S-rough sets in rough law mining-discovery of system are given. Function S-rough sets is a new research direction of rough sets and rough system. 展开更多
关键词 function S-rough sets structure of function S-rough sets relationship theorem rough law mining-discovery applications.
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Function S-rough sets and mining-discovery of rough law in systems 被引量:25
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作者 Shi Kaiquan Xia Jiarong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期919-926,共8页
Function S-rough sets (function singular rough sets) is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives... Function S-rough sets (function singular rough sets) is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives rough law generation model of a-function equivalence class, discussion on law mining and law discovery in systems, and application of law mining and law discovery in communication system. Function S-rough sets is a new theory and method in law mining research. 展开更多
关键词 function S-rough sets structure of function S-rough sets relationship theorem rough law mining-discovery applications.
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Rough Integrals Generated by Function Rough Sets 被引量:1
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作者 YU Xiu-qing XU Feng-sheng 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期296-299,共4页
The concepts of the lower approximation integral,the upper approximation integral and rough integrals are given on the basis of function rough sets.Based on these concepts,the relation of the lower approximation integ... The concepts of the lower approximation integral,the upper approximation integral and rough integrals are given on the basis of function rough sets.Based on these concepts,the relation of the lower approximation integrals,the relation of the upper approximation integrals,the relation of rough integrals,and the double median theorem of rough integrals are discussed.Rough integrals have finite contraction characteristic and finite extension characteristic. 展开更多
关键词 function rough sets the lower approximation integral the upper approximation integral rough integrals
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A Method of Gene-Function Annotation Based on Variable Precision Rough Sets 被引量:5
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作者 Zhi-li Pei Xiao-hu Shi +4 位作者 Meng Niu Xu-ning Tang Li-sha Liu Ying Kong Yan-chun Liang 《Journal of Bionic Engineering》 SCIE EI CSCD 2007年第3期177-184,共8页
It is very important in the field of bioinformatics to apply computer to perform the function annotation for new sequenced bio-sequences. Based on GO database and BLAST program, a novel method for the function annotat... It is very important in the field of bioinformatics to apply computer to perform the function annotation for new sequenced bio-sequences. Based on GO database and BLAST program, a novel method for the function annotation of new biological sequences is presented by using the variable-precision rough set theory. The proposed method is applied to the real data in GO database to examine its effectiveness. Numerical results show that the proposed method has better precision, recall-rate and harmonic mean value compared with existing methods. 展开更多
关键词 gene function ANNOTATION variable precision rough set GO BLAST
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On the global L^(1)-boundedness of Fourier integral operators with rough amplitude and phase functions
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作者 Joachim Sindayigaya WU Xiao-mei HUANG Qiang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第4期604-613,共10页
Let T_(ϕ,a)be a Fourier integral operator with amplitude a and phase functions ϕ.In this paper,we study the boundedness of Fourier integral operator of rough amplitude a∈L^(∞)S_(ρ)^(m)and rough phase functionsϕ∈L^... Let T_(ϕ,a)be a Fourier integral operator with amplitude a and phase functions ϕ.In this paper,we study the boundedness of Fourier integral operator of rough amplitude a∈L^(∞)S_(ρ)^(m)and rough phase functionsϕ∈L^(m)ϕ^(2)with some measure condition.We prove the global L^(1)boundedness for T_(ϕ,a),when 1/<ρ≤1 and m<ρ-n+1/2.Our theorem improves some known results. 展开更多
关键词 Fourier integral operators L1-Boundedness rough amplitude rough phase functions
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Research on the acoustic scattering function and coherence properties from rough seafloor based on finite element model
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作者 雷波 杨益新 +1 位作者 马远良 陈东旭 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第12期85-91,共7页
Acoustic scattering from a rough sea bottom is recognized as a main source of reverberation. In this study, scattering properties from a layered bottom were exploited based on the finite element model. The scattering ... Acoustic scattering from a rough sea bottom is recognized as a main source of reverberation. In this study, scattering properties from a layered bottom were exploited based on the finite element model. The scattering strength and loss from the layered rough seabed were investigated by ensembling the realizations of rough interface. They were found to be dependent on the thickness of sediment, and interference was significant in the case of thin sediment. Through verification of the finite element model, the scattering loss could be evaluated using the Eckart model with a proper sound speed in the thick sediment. The multiple scattering effect on the sound field was also exploited. It revealed that the effect depended strongly on the bottom type. 展开更多
关键词 finite element rough seafloor scattering function COHERENCE
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Bidirectional reflectance one-dimensional rough distribution function modeling of surface in the microwave band
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作者 郭立新 苟雪银 张连波 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期302-310,共9页
In this study, the bidirectional reflectance distribution function (BRDF) of a one-dimensional conducting rough surface and a dielectric rough surface are calculated with different frequencies and roughness values i... In this study, the bidirectional reflectance distribution function (BRDF) of a one-dimensional conducting rough surface and a dielectric rough surface are calculated with different frequencies and roughness values in the microwave band by using the method of moments, and the relationship between the bistatic scattering coefficient and the BRDF of a rough surface is expressed. From the theory of the parameters of the rough surface BRDF, the parameters of the BRDF are obtained using a genetic algorithm. The BRDF of a rough surface is calculated using the obtained parameter values. Further, the fitting values and theoretical calculations of the BRDF are compared, and the optimization results are in agreement with the theoretical calculation results. Finally, a reference for BRDF modeling of a Gaussian rough surface in the microwave band is provided by the proposed method. 展开更多
关键词 bidirectional reflectance distribution function rough surface genetic algorithm microwave band
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Effect of the Illuminating Point Spread Function and Roughness on the Speckle Correlation Field
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作者 Mohamed Mansour El-Nicklawy Amin Fahim Hassan +2 位作者 Adel Ebrahim Elmahdy Afaf Mahmoud Abd-Rabou Ezzulddin Abdoulsahib Eesee 《Optics and Photonics Journal》 2019年第11期165-177,共13页
Under conditions differing from those subjected for central limit theorem, the spatial autocorrelation function of speckle pattern resulting from illuminated rough surface is investigated. Its dependence on different ... Under conditions differing from those subjected for central limit theorem, the spatial autocorrelation function of speckle pattern resulting from illuminated rough surface is investigated. Its dependence on different illuminating apertures and the average of the roughness heights is presented theoretically and experimentally. The experiments were carried out using a set of circular and square apertures having different sizes. The results indicate that, increasing the size of the illuminating aperture leads to a decrease in the width of the main lobe of the spatial autocorrelation function. 展开更多
关键词 SPECKLE PATTERN AUTOCORRELATION function rough Surface
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Function S-rough sets and two law forecast
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作者 Fu Haiyan Shi Kaiquan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期332-338,共7页
Function S-rough sets has the properties of dynamics, heredity, and memory. Function S-rough sets is penetrated and crossed with the issue of economic law forecast, then a new forecast model based on function S-rough ... Function S-rough sets has the properties of dynamics, heredity, and memory. Function S-rough sets is penetrated and crossed with the issue of economic law forecast, then a new forecast model based on function S-rough sets namely the two law forecast model is proposed, which includes upper law forecast model and lower law forecast model; and its' implement algorithm is given. Finally, the validity of the model is demonstrated by the forecast for region economic development of Hainan Province. 展开更多
关键词 function S-rough sets two law forecast dynamic economic system
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Pseudo-Semi-Overlap Functions-Based Fuzzy Rough Sets Applied to Image Edge Extraction
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作者 Ran Yin Minge Chen +2 位作者 Yu Liu Yafei Zhao Jianwei Li 《Journal of Applied Mathematics and Physics》 2024年第7期2347-2366,共20页
As an extension of overlap functions, pseudo-semi-overlap functions are a crucial class of aggregation functions. Therefore, (I, PSO)-fuzzy rough sets are introduced, utilizing pseudo-semi-overlap functions, and furth... As an extension of overlap functions, pseudo-semi-overlap functions are a crucial class of aggregation functions. Therefore, (I, PSO)-fuzzy rough sets are introduced, utilizing pseudo-semi-overlap functions, and further extended for applications in image edge extraction. Firstly, a new clustering function, the pseudo-semi-overlap function, is introduced by eliminating the symmetry and right continuity present in the overlap function. The relaxed nature of this function enhances its applicability in image edge extraction. Secondly, the definitions of (I, PSO)-fuzzy rough sets are provided, using (I, PSO)-fuzzy rough sets, a pair of new fuzzy mathematical morphological operators (IPSOFMM operators) is proposed. Finally, by combining the fuzzy C-means algorithm and IPSOFMM operators, a novel image edge extraction algorithm (FCM-IPSO algorithm) is proposed and implemented. Compared to existing algorithms, the FCM-IPSO algorithm exhibits more image edges and a 73.81% decrease in the noise introduction rate. The outstanding performance of (I, PSO)-fuzzy rough sets in image edge extraction demonstrates their practical application value. 展开更多
关键词 Pseudo-Semi-Overlap functions Fuzzy rough Set Fuzzy Mathematical Morphology Image Edge Extraction
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Rough集理论:现状与前景 被引量:34
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作者 刘清 黄兆华 姚力文 《计算机科学》 CSCD 北大核心 1997年第4期1-5,共5页
经典逻辑中只有真、假二值,但实际上有大盆含糊现象存在于宾和假二值之间,因此,长以来许多逻辑学家和哲学家就致力于研究含糊概念。早在1904年谓词逻辑的创始人G.
关键词 rough集理论 计算机理论 人工智能
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Rough函数依赖及其推理机制 被引量:7
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作者 安秋生 沈钧毅 王国胤 《小型微型计算机系统》 CSCD 北大核心 2004年第4期638-641,共4页
在引入 Rough函数依赖的基础上 ,提出了先行上、下冗余因子及结果上、下冗余因子的概念 ,研究了 Rough函数依赖的性质和推理规则 ,最后分析了 Rough函数依赖与函数依赖。
关键词 Fuzzy函数依赖 rough函数依赖 rough冗余 冗余因子
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一种基于Rough Set的启发式属性约简算法 被引量:4
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作者 王天江 晏伟峰 漆志旺 《计算机工程与科学》 CSCD 2007年第2期86-88,共3页
属性约简的目的在于减少条件属性中不必要属性的数目,是知识发现中的关键问题之一。本文提出了一种改进的基于Rough集的启发式算法(IMSA),定义了新的启发函数(WSH)。这个函数考虑了所有隐藏规则集的质量,并且考虑了相关规则集的权重。... 属性约简的目的在于减少条件属性中不必要属性的数目,是知识发现中的关键问题之一。本文提出了一种改进的基于Rough集的启发式算法(IMSA),定义了新的启发函数(WSH)。这个函数考虑了所有隐藏规则集的质量,并且考虑了相关规则集的权重。在算法本身的时间复杂度没有增加的前提下,能够解决MSA算法遇到多个相同MSH值时无法处理的情况。实验分析表明,该算法是有效的。 展开更多
关键词 粗糙集 属性约简 启发函数
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变精度Rough隶属函数及其性质 被引量:1
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作者 司红颖 阙凤珍 梁俊奇 《模糊系统与数学》 CSCD 北大核心 2014年第3期157-159,共3页
简要介绍变精度粗糙集模型和Rough隶属函数及其性质,并给出了Rough隶属函数及其性质的证明。
关键词 变精度粗糙集 隶属函数 性质
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基于Rough集理论的模糊神经网络构造方法 被引量:4
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作者 黄显明 易继锴 《中国工程科学》 2004年第4期44-50,共7页
提出了在模糊神经网络中使用Rough集理论进行网络结构设计的方法。由于Rough集理论有强大的数值分析能力 ,而模糊神经网络具有准确的逼近收敛能力和较高的精度 ,所以通过两者的结合 ,可以得到一种可理解性好、计算简单、收敛速度快的神... 提出了在模糊神经网络中使用Rough集理论进行网络结构设计的方法。由于Rough集理论有强大的数值分析能力 ,而模糊神经网络具有准确的逼近收敛能力和较高的精度 ,所以通过两者的结合 ,可以得到一种可理解性好、计算简单、收敛速度快的神经网络模型。这种网络构造方法的主要过程为 :首先 ,利用Rough集理论对给定数据集进行规则获取 ;然后 ,根据这些规则构造模糊神经网络各层的神经元个数及相关参数初始值 ;最后 ,用BP算法迭代求出网络的各种参数 ,完成网络的设计。给出了一个二维非线性函数拟合的实例 。 展开更多
关键词 模糊神经网络 rough 规则获取 函数拟合
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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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基于Rough集理论的知识约简与规则挖掘方法 被引量:6
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作者 周庆敏 李永生 +1 位作者 殷晨波 陆金桂 《南京工业大学学报(自然科学版)》 CAS 2003年第4期33-36,共4页
提出了利用可辨识矩阵和分辨函数自动获取规则的算法,该算法从已知决策系统出发,通过决策系统的可辨识矩阵和分辨函数计算核和所有的约简集,以约简集为初始节点,建立层状节点网络模型,对于各节点,提取符合可信度要求的规则写入规则集中... 提出了利用可辨识矩阵和分辨函数自动获取规则的算法,该算法从已知决策系统出发,通过决策系统的可辨识矩阵和分辨函数计算核和所有的约简集,以约简集为初始节点,建立层状节点网络模型,对于各节点,提取符合可信度要求的规则写入规则集中。应用实例表明,文章提供的算法是确实可行的。 展开更多
关键词 rough 可辨识矩阵 分辨函数 约简集 决策系统 模糊性 不确定性
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若干Rough函数及其性质
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作者 梁俊奇 阙凤珍 《商丘师范学院学报》 CAS 2014年第12期15-17,共3页
简要介绍Rough函数的基本概念,给出并证明它们的性质,即定理1,2,3.
关键词 粗糙集 rough函数 性质
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基于Rough Sets理论的证据获取与合成方法 被引量:12
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作者 杨善林 刘业政 李亚飞 《管理科学学报》 CSSCI 北大核心 2005年第5期69-75,共7页
证据理论是处理不确定性问题的有力工具,它处理的证据来源于专家.专家的知识经验是有限的,获取较困难,且可能存在一定的主观性.针对上述问题,提出了一种基于粗糙集理论的证据获取的新方法,并对证据合成和应用进行了研究.首先研究了大型... 证据理论是处理不确定性问题的有力工具,它处理的证据来源于专家.专家的知识经验是有限的,获取较困难,且可能存在一定的主观性.针对上述问题,提出了一种基于粗糙集理论的证据获取的新方法,并对证据合成和应用进行了研究.首先研究了大型决策表分解问题.利用粗糙集理论分析条件属性间的依赖关系,对条件属性集进行聚类,形成多个条件属性集相对独立的子决策表;其次对各子决策表进行分析,利用粗糙集的分类思想和隶属度概念,计算证据的基本可信度分配;最后文章对证据的合成及其在决策分析中的应用进行了研究,提出了相应的解决方法. 展开更多
关键词 证据理论 粗糙集 依赖度 基本可信度分配 信度函数
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