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Generating Type 2 Trapezoidal Fuzzy Membership Function Using Genetic Tuning
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作者 Siti Hajar Khairuddin Mohd Hilmi Hasan +1 位作者 Emilia Akashah P.Akhir Manzoor Ahmed Hashmani 《Computers, Materials & Continua》 SCIE EI 2022年第4期717-734,共18页
Fuzzy inference system(FIS)is a process of fuzzy logic reasoning to produce the output based on fuzzified inputs.The system starts with identifying input from data,applying the fuzziness to input using membership func... Fuzzy inference system(FIS)is a process of fuzzy logic reasoning to produce the output based on fuzzified inputs.The system starts with identifying input from data,applying the fuzziness to input using membership functions(MF),generating fuzzy rules for the fuzzy sets and obtaining the output.There are several types of input MFs which can be introduced in FIS,commonly chosen based on the type of real data,sensitivity of certain rule implied and computational limits.This paper focuses on the construction of interval type 2(IT2)trapezoidal shape MF from fuzzy C Means(FCM)that is used for fuzzification process of mamdani FIS.In the process,upper MF(UMF)and lower MF(LMF)of the MF need to be identified to get the range of the footprint of uncertainty(FOU).This paper proposes Genetic tuning process,which is a part of genetic algorithm(GA),to adjust parameters in order to improve the behavior of existing system,especially to enhance the accuracy of the system model.This novel process is a hybrid approach which produces Genetic Fuzzy System(GFS)that helps to enhance fuzzy classification problems and performance.The approach provides a new method for the construction and tuning process of the IT2 MF,based on the FCM outcomes.The result is compared to Gaussian shape IT2 MF and trapezoid IT2 MF generated by the classic GA method.It is shown that the proposed approach is able to outperform the mentioned benchmarked approaches.The work implies a wider range of IT2 MF types,constructed based on FCM outcomes,and an optimum generation of the FOU so that it can be implemented in practical applications such as prediction,analytics and rule-based solutions. 展开更多
关键词 fuzzy inference system membership function genetic tuning lateral adjustment trapezoidal MF fuzzy C means
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New Approaches to the Prognosis and Diagnosis of Breast Cancer Using Fuzzy Expert Systems
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作者 Elias Ayinbila Apasiya Abdul-Mumin Salifu Peter Awon-Natemi Agbedemnab 《Journal of Computer and Communications》 2024年第5期151-169,共19页
Breast cancer remains a significant global health challenge, necessitating effective early detection and prognosis to enhance patient outcomes. Current diagnostic methods, including mammography and MRI, suffer from li... Breast cancer remains a significant global health challenge, necessitating effective early detection and prognosis to enhance patient outcomes. Current diagnostic methods, including mammography and MRI, suffer from limitations such as uncertainty and imprecise data, leading to late-stage diagnoses. To address this, various expert systems have been developed, but many rely on type-1 fuzzy logic and lack mobile-based applications for data collection and feedback to healthcare practitioners. This research investigates the development of an Enhanced Mobile-based Fuzzy Expert system (EMFES) for breast cancer pre-growth prognosis. The study explores the use of type-2 fuzzy logic to enhance accuracy and model uncertainty effectively. Additionally, it evaluates the advantages of employing the python programming language over java for implementation and considers specific risk factors for data collection. The research aims to dynamically generate fuzzy rules, adapting to evolving breast cancer research and patient data. Key research questions focus on the comparative effectiveness of type-2 fuzzy logic, the handling of uncertainty and imprecise data, the integration of mobile-based features, the choice of programming language, and the creation of dynamic fuzzy rules. Furthermore, the study examines the differences between the Mamdani Inference System and the Sugeno Fuzzy Inference method and explores challenges and opportunities in deploying the EMFES on mobile devices. The research identifies a critical gap in existing breast cancer diagnostic systems, emphasizing the need for a comprehensive, mobile-enabled, and adaptable solution by developing an EMFES that leverages Type-2 fuzzy logic, the Sugeno Inference Algorithm, Python Programming, and dynamic fuzzy rule generation. This study seeks to enhance early breast cancer detection and ultimately reduce breast cancer-related mortality. 展开更多
关键词 EMFES Breast Cancer Type-2 Fl Soft Computing membership functions fuzzy set fuzzy Rules Risk Factors.
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Describing Fuzzy Membership Function and Detecting the Outlier by Using Five Number Summary of Data
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作者 Md. Farooq Hasan Md. Abdus Sobhan 《American Journal of Computational Mathematics》 2020年第3期410-424,共15页
One of the most important activities in data science is defining a membership function in fuzzy system. Although there are few ways to describe membership function like artificial neural networks, genetic algorithms e... One of the most important activities in data science is defining a membership function in fuzzy system. Although there are few ways to describe membership function like artificial neural networks, genetic algorithms etc.;they are very complex and time consuming. On the other hand, the presence of outlier in a data set produces deceptive results in the modeling. So it is important to detect and eliminate them to prevent their negative effect on the modeling. This paper describes a new and simple way of constructing fuzzy membership function by using five-number summary of a data set. Five states membership function can be created in this new method. At the same time, if there is any outlier in the data set, it can be detected with the help of this method. Usually box plot is used to identify the outliers of a data set. So along with the new approach, the box plot has also been drawn so that it is understood that the results obtained in the new method are accurate. Several real life examples and their analysis have been discussed with graph to demonstrate the potential of the proposed method. The results obtained show that the proposed method has given good results. In the case of outlier, the proposed method and the box plot method have shown similar results. Primary advantage of this new procedure is that it is not as expensive as neural networks, and genetic algorithms. 展开更多
关键词 fuzzy set membership function Five Number Summary OUTLIERS
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Traffic Flow Data Forecasting Based on Interval Type-2 Fuzzy Sets Theory 被引量:4
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作者 Runmei Li Chaoyang Jiang +1 位作者 Fenghua Zhu Xiaolong Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第2期141-148,共8页
This paper proposes a long-term forecasting scheme and implementation method based on the interval type-2 fuzzy sets theory for traffic flow data. The type-2 fuzzy sets have advantages in modeling uncertainties becaus... This paper proposes a long-term forecasting scheme and implementation method based on the interval type-2 fuzzy sets theory for traffic flow data. The type-2 fuzzy sets have advantages in modeling uncertainties because their membership functions are fuzzy. The scheme includes traffic flow data preprocessing module, type-2 fuzzification operation module and long-term traffic flow data forecasting output module, in which the Interval Approach acts as the core algorithm. The central limit theorem is adopted to convert point data of mass traffic flow in some time range into interval data of the same time range(also called confidence interval data) which is being used as the input of interval approach. The confidence interval data retain the uncertainty and randomness of traffic flow, meanwhile reduce the influence of noise from the detection data. The proposed scheme gets not only the traffic flow forecasting result but also can show the possible range of traffic flow variation with high precision using upper and lower limit forecasting result. The effectiveness of the proposed scheme is verified using the actual sample application. 展开更多
关键词 Interval type-2 fuzzy sets central limit theorem confidence interval long-term prediction
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New Methods of Fitting the Membership Function of Oceanic Water Masses 被引量:2
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作者 LIFengqi XIEJun LIYao 《Journal of Ocean University of China》 SCIE CAS 2004年第1期1-9,共9页
After reviewing the analytical theories of T S curve, some methods of T S relationship, and fuzzy sets for studying water masses, new methods of fitting the membership function of oceanic water masses are presented ba... After reviewing the analytical theories of T S curve, some methods of T S relationship, and fuzzy sets for studying water masses, new methods of fitting the membership function of oceanic water masses are presented based on the characteristics of T S curve family of oceanic water masses. The membership functions of oceanic Subsurface Water Mass with high salinity and Intermediate Water Mass with low salinity are fitted and discussed using the new methods. The proposed methods are useful in analyzing the mixing and modifying processes of these water masses, especially in tracing their sources. The principles and formulae of the new methods and examples are given. 展开更多
关键词 海洋 水团 模糊系统 南海 盐分
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Modelling spatial vagueness based on type-2 fuzzy set 被引量:1
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作者 杜国宁 朱仲英 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第2期250-256,共7页
The modelling and formal characterization of spatial vagueness plays an increasingly important role in the imple- mentation of Geographic Information System (GIS). The concepts involved in spatial objects of GIS have ... The modelling and formal characterization of spatial vagueness plays an increasingly important role in the imple- mentation of Geographic Information System (GIS). The concepts involved in spatial objects of GIS have been investigated and acknowledged as being vague and ambiguous. Models and methods which describe and handle fuzzy or vague (rather than crisp or determinate) spatial objects, will be more necessary in GIS. This paper proposes a new method for modelling spatial vagueness based on type-2 fuzzy set, which is distinguished from the traditional type-1 fuzzy methods and more suitable for describing and implementing the vague concepts and objects in GIS. 展开更多
关键词 GIS 模糊理论 模糊集 地理信息系统 隶属函数 建模 空间信息
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A NEW UNSUPERVISED CLASSIFICATION ALGORITHM FOR POLARIMETRIC SAR IMAGES BASED ON FUZZY SET THEORY 被引量:2
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作者 Fu Yusheng Xie Yan Pi Yiming Hou Yinming 《Journal of Electronics(China)》 2006年第4期598-601,共4页
In this letter, a new method is proposed for unsupervised classification of terrain types and man-made objects using POLarimetric Synthetic Aperture Radar (POLSAR) data. This technique is a combi-nation of the usage o... In this letter, a new method is proposed for unsupervised classification of terrain types and man-made objects using POLarimetric Synthetic Aperture Radar (POLSAR) data. This technique is a combi-nation of the usage of polarimetric information of SAR images and the unsupervised classification method based on fuzzy set theory. Image quantization and image enhancement are used to preprocess the POLSAR data. Then the polarimetric information and Fuzzy C-Means (FCM) clustering algorithm are used to classify the preprocessed images. The advantages of this algorithm are the automated classification, its high classifica-tion accuracy, fast convergence and high stability. The effectiveness of this algorithm is demonstrated by ex-periments using SIR-C/X-SAR (Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar) data. 展开更多
关键词 雷达偏振测定法 人造孔径雷达 模糊集 图像量子画
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INVESTIGATION ON MAKING MEMBERSHIP FUNCTION OF WATER MASS FROM MIXING MODIFIED PROCESS
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作者 李凤岐 苏育嵩 +1 位作者 喻祖祥 王凤钦 《中国海洋大学学报(自然科学版)》 CAS CSCD 1989年第S1期445-461,共17页
A water mass in the sea area under investigation is defined as a fuzzy subset in the discourse universe. Possible forms of membership function of water masses in the mixing modified process are discussed with the mixi... A water mass in the sea area under investigation is defined as a fuzzy subset in the discourse universe. Possible forms of membership function of water masses in the mixing modified process are discussed with the mixing theory for conservative concentration of sea water. It may provide bases for making membership functions. Results in this paper may be extended and applied to shallow water. Examples and discussion are given in this paper. 展开更多
关键词 water MASS fuzzy setS membership function the measure-value space
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DISCUSSION OF SOME CONCEPTIONS OF A WATER MASS BASED ON THE THEORY OF FUZZY SETS
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作者 李凤岐 苏育嵩 +1 位作者 王凤钦 喻祖祥 《中国海洋大学学报(自然科学版)》 CAS CSCD 1989年第S1期430-444,共15页
The fundamental principle for differentiating water masses is a strict consideration of their relative "interior homogeneity" and obvious "exterior differences" with others in characteristics. The ... The fundamental principle for differentiating water masses is a strict consideration of their relative "interior homogeneity" and obvious "exterior differences" with others in characteristics. The conceptions of water type, water mass and water system are dealt with on the basis of the theory of fuzzy sets. A proposal to apply the theory of fuzzy sets to define the water mass and its core, independent area, boundary and mixing area is put forward.As an example, the membership function of the surface water masses in the Yellow Sea and East China Sea in August, 1979, are considered. Their cores, independent areas, boundaries, mixing areas and the approximation degrees between different water masses are calculated respectively. The water masses are ranged according to their fuzzy degrees. 展开更多
关键词 WATER mass fuzzy setS WATER type WATER system membership function the YELLOW SEA the East China SEA
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Research on Method R_w for Discrete Membership Functions
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作者 崔宝灵 黄梯云 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第2期10-12,共3页
In this paper, a number of concepts related to continuous membership function (CMFs) advanced in [2] are extended to discrete membership functions (DMFs) in the light of the characteristics of DMFs so that fuzzy reaso... In this paper, a number of concepts related to continuous membership function (CMFs) advanced in [2] are extended to discrete membership functions (DMFs) in the light of the characteristics of DMFs so that fuzzy reasoning method R. based upon CMFs suits the case of DMFs. 展开更多
关键词 fuzzy setS membership function fuzzy REASONING
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Commonsense Reasoning and Nonmonotonic Aggregation Connectives on Fuzzy Sets
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作者 刘东波 《High Technology Letters》 EI CAS 1995年第2期43-47,共5页
Commonsense representation and manipulation based on fuzzy logic is a new research field which handles the incompleteness, error-tolerability (allow exceptions) and uncertainty associated with commonsense knowledge. I... Commonsense representation and manipulation based on fuzzy logic is a new research field which handles the incompleteness, error-tolerability (allow exceptions) and uncertainty associated with commonsense knowledge. In this paper, we introduce a pair of nonmonotonic aggregation connectives on fuzzy sets-soft intersection and soft union, in the light of Zadeh’s fuzzy set theory. Some important features of the nonmonotonic connectives are also discussed. 展开更多
关键词 cussed. Commonsense knowledge Nonmonotonic REASONING fuzzy sets SOFT INTERSECTION SOFT UNION
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Big Data Audit of Banks Based on Fuzzy Set Theory to Evaluate Risk Level
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作者 Yilin Bi Yuxin Ouyang +3 位作者 Guang Sun Peng Guo Jianjun Zhang Yijun Ai 《Journal on Big Data》 2020年第1期9-18,共10页
The arrival of big data era has brought new opportunities and challenges to the development of various industries in China.The explosive growth of commercial bank data has brought great pressure on internal audit.The ... The arrival of big data era has brought new opportunities and challenges to the development of various industries in China.The explosive growth of commercial bank data has brought great pressure on internal audit.The key audit of key products limited to key business areas can no longer meet the needs.It is difficult to find abnormal and exceptional risks only by sampling analysis and static analysis.Exploring the organic integration and business processing methods between big data and bank internal audit,Internal audit work can protect the stable and sustainable development of banks under the new situation.Therefore,based on fuzzy set theory,this paper determines the membership degree of audit data through membership function,and judges the risk level of audit data,and builds a risk level evaluation system.The main features of this paper are as follows.First,it analyzes the necessity of transformation of the bank auditing in the big data environment.The second is to combine the determination of the membership function in the fuzzy set theory with the bank audit analysis,and use the model to calculate the corresponding parameters,thus establishing a risk level assessment system.The third is to propose audit risk assessment recommendations,hoping to help bank audit risk management in the big data environment.There are some shortcomings in this paper.First,the amount of data acquired is not large enough.Second,due to the lack of author’knowledge,there are still some deficiencies in the analysis of audit risk of commercial banks. 展开更多
关键词 Bank audit fuzzy set theory membership function risk control
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Modeling Multisource-heterogeneous Information Based on Random Set and Fuzzy Set Theory
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作者 文成林 徐晓滨 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期87-92,共6页
This paper presents a new idea, named as modeling multisensor-heterogeneous information, to incorporate the fuzzy logic methodologies with mulitsensor-multitarget system under the framework of random set theory. First... This paper presents a new idea, named as modeling multisensor-heterogeneous information, to incorporate the fuzzy logic methodologies with mulitsensor-multitarget system under the framework of random set theory. Firstly, based on strong random set and weak random set, the unified form to describe both data (unambiguous information) and fuzzy evidence (uncertain information) is introduced. Secondly, according to signatures of fuzzy evidence, two Bayesian-markov nonlinear measurement models are proposed to fuse effectively data and fuzzy evidence. Thirdly, by use of "the models-based signature-matching scheme", the operation of the statistics of fuzzy evidence defined as random set can be translated into that of the membership functions of relative point state variables. These works are the basis to construct qualitative measurement models and to fuse data and fuzzy evidence. 展开更多
关键词 模糊分析法 信息处理 计算机技术 建模方法
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A new approach of fuzzy comprehensive evaluation on rough set
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作者 ZENG Huang-lin CHEN Shun-ling 《通讯和计算机(中英文版)》 2008年第10期33-36,共4页
关键词 模糊综合评价 粗糙集 计算方法 逻辑关系
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Vague集向Fuzzy集转化的方法分析 被引量:4
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作者 范平 戴文华 桂学勤 《计算机工程与应用》 CSCD 北大核心 2010年第24期48-50,共3页
介绍了Vague集与Fuzzy集的特点,结合Vague集理论及投票模型下的解释,对Vague集向Fuzzy集转化的多种方法进行了分析,指出已有方法的不足,根据Vague集的三维特性并结合人的心理变化情况首次直观地提出一种新的有效非线性方法,并通过实例... 介绍了Vague集与Fuzzy集的特点,结合Vague集理论及投票模型下的解释,对Vague集向Fuzzy集转化的多种方法进行了分析,指出已有方法的不足,根据Vague集的三维特性并结合人的心理变化情况首次直观地提出一种新的有效非线性方法,并通过实例说明该方法的正确性和直观性。 展开更多
关键词 VAGUE集 fuzzy 隶属函数 转化方法
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一种Vague集转化为Fuzzy集的方法 被引量:9
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作者 黄志伟 何明瑞 《计算机工程与应用》 CSCD 北大核心 2007年第1期57-60,共4页
已存在的Vague集向Fuzzy集转化的多种模型都存在着一定缺陷。论文从另一种角度探讨了Vague集到Fuzzy集的转化,它把模糊隶属度看成是参数k的函数,这样在计算模糊隶属度时,只需给定满足条件的参数k即可;另一方面,在进行模糊信息处理时,会... 已存在的Vague集向Fuzzy集转化的多种模型都存在着一定缺陷。论文从另一种角度探讨了Vague集到Fuzzy集的转化,它把模糊隶属度看成是参数k的函数,这样在计算模糊隶属度时,只需给定满足条件的参数k即可;另一方面,在进行模糊信息处理时,会遇到一些不确定因素,如果所得到的模糊隶属度与实际结果有些偏差,可根据参数k的数学性质有目的地调整k,而不必去重新建立方法模型,因此,此方法比已存在方法灵活,适用;文章也对已有的转化方法与所提模型进行了比较,说明了所提模型的正确性及有效性。 展开更多
关键词 fuzzy VAGUE集 隶属函数
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一种Vague集向Fuzzy集转化的新方法 被引量:5
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作者 周孟 余建坤 《计算机工程与应用》 CSCD 北大核心 2011年第36期65-67,共3页
基于Vague集理论及投票模型下的解释,介绍了Vague集向Fuzzy集转化的一些方法,并指出了这些方法的不足,在此基础上提出了一种新的转化方法,并证明了该方法的有效性,实例表明该方法比已有的方法更合理。
关键词 VAGUE集 fuzzy 隶属函数
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施工网络计划的Fuzzy方法 被引量:8
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作者 孙林柱 黄蔚 《浙江师大学报(自然科学版)》 CAS 2001年第1期29-33,共5页
采用模糊数学的方法 ,确定了网络图中工序时间的隶属函数 ,利用λ-截集时间参数的计算公式 ,可求得模糊网络各工序λ-截集的时间参数及关键线路的模糊完成期 .此方法可行、实用 ,更接近工程实际 ,优于传统的 PERT法 .
关键词 隶属函数 时间参数 Λ-截集 模糊完成期 施工网络计划 模糊数学方法 模糊网络
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D.C.隶属函数模糊集及其应用(II)——D.C.隶属函数模糊集的万能逼近性 被引量:3
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作者 邱中华 李雷 《模糊系统与数学》 CSCD 北大核心 2006年第2期50-60,共11页
本文是D.C.隶属函数模糊集及其应用系列研究的第二部分。指出在实际问题中普遍选用的三角形、半三角形、梯形、半梯形、高斯型、柯西型、S形、Z形、π形隶属函数模糊集等均为D.C.隶属函数模糊集,建立了D.C.隶属函数模糊集对模糊集的万... 本文是D.C.隶属函数模糊集及其应用系列研究的第二部分。指出在实际问题中普遍选用的三角形、半三角形、梯形、半梯形、高斯型、柯西型、S形、Z形、π形隶属函数模糊集等均为D.C.隶属函数模糊集,建立了D.C.隶属函数模糊集对模糊集的万有逼近性。探讨了D.C.隶属函数模糊集与模糊数之间的关系,给出了用D.C.隶属函数模糊集逼近模糊数的-εC e llina逼近形式,得到模糊数与D.C.函数之间的一个对应算子,指出了用模糊数表示D.C.函数的问题。 展开更多
关键词 d.c.隶属函数模糊集 逼近 模糊数
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基于等量效果的Vague集转化为Fuzzy集的方法 被引量:2
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作者 罗军 钟毓 《计算机应用》 CSCD 北大核心 2011年第1期104-106,共3页
当前Vague集转化为Fuzzy集的方法更多是根据直观,而没能详细阐述所基于的原理。为能更好理解Vague集转化为Fuzzy集的过程,考虑将Vague集转化为Fuzzy集模拟为一个最终无弃权票的多轮投票过程,从而构造了一种效果函数的定义,用以表示支持... 当前Vague集转化为Fuzzy集的方法更多是根据直观,而没能详细阐述所基于的原理。为能更好理解Vague集转化为Fuzzy集的过程,考虑将Vague集转化为Fuzzy集模拟为一个最终无弃权票的多轮投票过程,从而构造了一种效果函数的定义,用以表示支持力度。并结合积分第一中值定理的意义提出了一种新的基于等量效果的转化方法,以保证在转化过程中,所关心的总效果没有发生变化。最后结合实例,严格分析了该方法的良好性质以及合理性。 展开更多
关键词 fuzzy VAGUE集 效果函数 真/假隶属函数 转化方法
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