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Novel moderate transformation of fuzzy membership function into basic belief assignment
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作者 Xiaojing FAN Deqiang HAN +1 位作者 Jean DEZERT Yi YANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第1期369-385,共17页
In information fusion,the uncertain information from different sources might be modeled with different theoretical frameworks.When one needs to fuse the uncertain information represented by different uncertainty theor... In information fusion,the uncertain information from different sources might be modeled with different theoretical frameworks.When one needs to fuse the uncertain information represented by different uncertainty theories,constructing the transformation between different frameworks is crucial.Various transformations of a Fuzzy Membership Function(FMF)into a Basic Belief Assignment(BBA)have been proposed,where the transformations based on uncertainty maximization and minimization can determine the BBA without preselecting the focal elements.However,these two transformations that based on uncertainty optimization emphasize the extreme cases of uncertainty.To avoid extreme attitudinal bias,a trade-off or moderate BBA with the uncertainty degree between the minimal and maximal ones is more preferred.In this paper,two moderate transformations of an FMF into a trade-off BBA are proposed.One is the weighted average based transformation and the other is the optimization-based transformation with weighting mechanism,where the weighting factor can be user-specified or determined with some prior information.The rationality and effectiveness of our transformations are verified through numerical examples and classification examples. 展开更多
关键词 Basic belief assignment Belief functions fuzzy membership function Information fusion Moderate transformation
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Insulation and Flame Retardancy Improvement of PBDEs Using 3D-QSAR Model Combined with a Fuzzy Membership Function Method
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作者 ZHANG Shujing XIAO Jiapeng +1 位作者 CHEN Xinyi LI Yu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2021年第3期729-738,共10页
A three-dimensional quantitative structure-activity relationship(3D-QSAR)model based on the fuzzy membership function method was developed in this study,and then the model was applied to the molecular design of the en... A three-dimensional quantitative structure-activity relationship(3D-QSAR)model based on the fuzzy membership function method was developed in this study,and then the model was applied to the molecular design of the enhanced comprehensive activities(insulation/flame retardancy)of polybrominated diphenyl ethers(PBDEs)considering their environmental behavior control,to develop environmental-friendly PBDE derivatives with outstanding functionality.Firstly,a fuzzy membership function method was employed to characterize the evaluation values of comprehensive activities of the functional properties of PBDEs based on the 3D-QSAR model.Secondly,a comprehensive activity 3D-QSAR model(CoMFA)of the functional properties of PBDEs was established,which demonstrated robustness and good predictive ability.Thirdly,a molecular modification scheme was designed to enhance the comprehensive activity of the functional properties of PBDEs considering the PBDE homologs BDE-138,BDE-183,and BDE-209 as target molecules.The resulting information indicated that the four PBDE derivatives with significantly enhanced functional properties,such as passing screening for toxicity,bioconcentration,migration,and biodegradability assessments with environmentally friendly results,were successfully designed(43.57%-82.14%enhancement).Finally,the mechanism analysis indicated that the enhanced functional properties of the modified PBDE derivatives were significantly related to the substitution positions and substitution groups of PBDEs. 展开更多
关键词 Polybrominated diphenyl ether Three-dimensional quantitative structure-activity relationship fuzzy membership function method Insulation/flame retardancy Molecular modification
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Energy Price Forecasting Through Novel Fuzzy Type-1 Membership Functions
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作者 Muhammad Hamza Azam Mohd Hilmi Hasan +2 位作者 Azlinda A Malik Saima Hassan Said Jadid Abdulkadir 《Computers, Materials & Continua》 SCIE EI 2022年第10期1799-1815,共17页
Electricity price forecasting is a subset of energy and power forecasting that focuses on projecting commercial electricity market present and future prices.Electricity price forecasting have been a critical input to ... Electricity price forecasting is a subset of energy and power forecasting that focuses on projecting commercial electricity market present and future prices.Electricity price forecasting have been a critical input to energy corporations’strategic decision-making systems over the last 15 years.Many strategies have been utilized for price forecasting in the past,however Artificial Intelligence Techniques(Fuzzy Logic and ANN)have proven to be more efficient than traditional techniques(Regression and Time Series).Fuzzy logic is an approach that uses membership functions(MF)and fuzzy inference model to forecast future electricity prices.Fuzzy c-means(FCM)is one of the popular clustering approach for generating fuzzy membership functions.However,the fuzzy c-means algorithm is limited to producing only one type of MFs,Gaussian MF.The generation of various fuzzy membership functions is critical since it allows for more efficient and optimal problem solutions.As a result,for the best and most improved results for electricity price forecasting,an approach to generate multiple type-1 fuzzy MFs using FCM algorithm is required.Therefore,the objective of this paper is to propose an approach for generating type-1 fuzzy triangular and trapezoidal MFs using FCM algorithm to overcome the limitations of the FCM algorithm.The approach is used to compute and improve forecasting accuracy for electricity prices,where Australian Energy Market Operator(AEMO)data is used.The results show that the proposed approach of using FCM to generate type-1 fuzzy MFs is effective and can be adopted. 展开更多
关键词 fuzzy logic fuzzy C-means type-1 fuzzy membership function electricity price forecasting
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RBF neural network regression model based on fuzzy observations 被引量:1
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作者 朱红霞 沈炯 苏志刚 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期400-406,共7页
A fuzzy observations-based radial basis function neural network (FORBFNN) is presented for modeling nonlinear systems in which the observations of response are imprecise but can be represented as fuzzy membership fu... A fuzzy observations-based radial basis function neural network (FORBFNN) is presented for modeling nonlinear systems in which the observations of response are imprecise but can be represented as fuzzy membership functions. In the FORBFNN model, the weight coefficients of nodes in the hidden layer are identified by using the fuzzy expectation-maximization ( EM ) algorithm, whereas the optimal number of these nodes as well as the centers and widths of radial basis functions are automatically constructed by using a data-driven method. Namely, the method starts with an initial node, and then a new node is added in a hidden layer according to some rules. This procedure is not terminated until the model meets the preset requirements. The method considers both the accuracy and complexity of the model. Numerical simulation results show that the modeling method is effective, and the established model has high prediction accuracy. 展开更多
关键词 radial basis function neural network (RBFNN) fuzzy membership function imprecise observation regression model
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Similarity measure design and similarity computation for discrete fuzzy data 被引量:7
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作者 LEE Sang-Hyuk PARK Wook-Je JUNG Dong-yean 《Journal of Central South University》 SCIE EI CAS 2011年第5期1602-1608,共7页
The similarity computations for fuzzy membership function pairs were carried out.Fuzzy number related knowledge was introduced,and conventional similarity was compared with distance based similarity measure.The useful... The similarity computations for fuzzy membership function pairs were carried out.Fuzzy number related knowledge was introduced,and conventional similarity was compared with distance based similarity measure.The usefulness of the proposed similarity measure was verified.The results show that the proposed similarity measure could be applied to ordinary fuzzy membership functions,though it was not easy to design.Through conventional results on the calculation of similarity for fuzzy membership pair,fuzzy membership-crisp pair and crisp-crisp pair were carried out.The proposed distance based similarity measure represented rational performance with the heuristic point of view.Furthermore,troublesome in fuzzy number based similarity measure for abnormal universe of discourse case was discussed.Finally,the similarity measure computation for various membership function pairs was discussed with other conventional results. 展开更多
关键词 similarity measure fuzzy number DISTANCE similarity evaluation fuzzy membership function
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Fuzzy entropy design for non convex fuzzy set and application to mutual information 被引量:7
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作者 LEE Sang-Hyuk LEE Sang-Min +1 位作者 SOHN Gyo-Yong KIM Jaeh-Yung 《Journal of Central South University》 SCIE EI CAS 2011年第1期184-189,共6页
Fuzzy entropy was designed for non convex fuzzy membership function using well known Hamming distance measure.The proposed fuzzy entropy had the same structure as that of convex fuzzy membership case.Design procedure ... Fuzzy entropy was designed for non convex fuzzy membership function using well known Hamming distance measure.The proposed fuzzy entropy had the same structure as that of convex fuzzy membership case.Design procedure of fuzzy entropy was proposed by considering fuzzy membership through distance measure,and the obtained results contained more flexibility than the general fuzzy membership function.Furthermore,characteristic analyses for non convex function were also illustrated.Analyses on the mutual information were carried out through the proposed fuzzy entropy and similarity measure,which was also dual structure of fuzzy entropy.By the illustrative example,mutual information was discussed. 展开更多
关键词 fuzzy entropy non convex fuzzy membership function distance measure similarity measure mutual information
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FEW-NNN: A Fuzzy Entropy Weighted Natural Nearest Neighbor Method for Flow-Based Network Traffic Attack Detection 被引量:7
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作者 Liangchen Chen Shu Gao +2 位作者 Baoxu Liu Zhigang Lu Zhengwei Jiang 《China Communications》 SCIE CSCD 2020年第5期151-167,共17页
Attacks such as APT usually hide communication data in massive legitimate network traffic, and mining structurally complex and latent relationships among flow-based network traffic to detect attacks has become the foc... Attacks such as APT usually hide communication data in massive legitimate network traffic, and mining structurally complex and latent relationships among flow-based network traffic to detect attacks has become the focus of many initiatives. Effectively analyzing massive network security data with high dimensions for suspicious flow diagnosis is a huge challenge. In addition, the uneven distribution of network traffic does not fully reflect the differences of class sample features, resulting in the low accuracy of attack detection. To solve these problems, a novel approach called the fuzzy entropy weighted natural nearest neighbor(FEW-NNN) method is proposed to enhance the accuracy and efficiency of flowbased network traffic attack detection. First, the FEW-NNN method uses the Fisher score and deep graph feature learning algorithm to remove unimportant features and reduce the data dimension. Then, according to the proposed natural nearest neighbor searching algorithm(NNN_Searching), the density of data points, each class center and the smallest enclosing sphere radius are determined correspondingly. Finally, a fuzzy entropy weighted KNN classification method based on affinity is proposed, which mainly includes the following three steps: 1、 the feature weights of samples are calculated based on fuzzy entropy values, 2、 the fuzzy memberships of samples are determined based on affinity among samples, and 3、 K-neighbors are selected according to the class-conditional weighted Euclidean distance, the fuzzy membership value of the testing sample is calculated based on the membership of k-neighbors, and then all testing samples are classified according to the fuzzy membership value of the samples belonging to each class;that is, the attack type is determined. The method has been applied to the problem of attack detection and validated based on the famous KDD99 and CICIDS-2017 datasets. From the experimental results shown in this paper, it is observed that the FEW-NNN method improves the accuracy and efficiency of flow-based network traffic attack detection. 展开更多
关键词 fuzzy entropy weighted KNN network attack detection fuzzy membership natural nearest neighbor network security intrusion detection system
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Fuzzy smooth support vector machine with different smooth functions 被引量:5
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作者 Chuandong Qin Sanyang Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第3期460-466,共7页
Smooth support vector machine (SSVM) changs the normal support vector machine (SVM) into the unconstrained op- timization by using the smooth sigmoid function. The method can be solved under the Broyden-Fletcher-G... Smooth support vector machine (SSVM) changs the normal support vector machine (SVM) into the unconstrained op- timization by using the smooth sigmoid function. The method can be solved under the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm and the Newdon-Armijio (NA) algorithm easily, however the accuracy of sigmoid function is not as good as that of polyno- mial smooth function. Furthermore, the method cannot reduce the influence of outliers or noise in dataset. A fuzzy smooth support vector machine (FSSVM) with fuzzy membership and polynomial smooth functions is introduced into the SVM. The fuzzy member- ship considers the contribution rate of each sample to the optimal separating hyperplane and makes the optimization problem more accurate at the inflection point. Those changes play a positive role on trials. The results of the experiments show that those FSSVMs can obtain a better accuracy and consume the shorter time than SSVM and lagrange support vector machine (LSVM). 展开更多
关键词 smooth support vector machine (SSVM) fuzzy sig- moid function polynomial smooth function fuzzy membership Broyden-Fletcher-Gddfarb-Shanno (BFGS).
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Fuzzy Support Vector Regression Model of 4-CBA Concentration for Industrial PTA Oxidation Process 被引量:3
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作者 张英 苏宏业 +1 位作者 刘瑞兰 褚健 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第5期642-648,共7页
In the past few years, support vector machines (SVMs) have been applied to many fields, such as pattern recognition and data mining, etc. However there still exist some problems to be solved. One of them is that the S... In the past few years, support vector machines (SVMs) have been applied to many fields, such as pattern recognition and data mining, etc. However there still exist some problems to be solved. One of them is that the SVM is very sensitive to outliers or noises because of over-fitting problem. In this paper, a fuzzy support vector regression (FSVR) method is presented to deal with this problem. Strategies based on k nearest neighbor (kNN) and support vector data description (SVDD) are adopted to set the fuzzy membership values of data points in FSVR.The proposed FSVR soft sensor models based on kNN and SVDD are employed to predict the concentration of 4-carboxy-benzaldehyde (4-CBA) in purified terephthalic acid (PTA) oxidation process. Simulation results indicate that the proposed method indeed reduces the effect of outliers and yields higher accuracy. 展开更多
关键词 purified terephthalic acid 4-carboxy-benzaldehyde support vector machines soft sensor fuzzy membership
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Fuzzy Comprehensive Evaluation for Decision Making of Water Saving Irrigation System 被引量:3
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作者 Luo Jin\|yao, Qiu Yuan\|feng College of Water Resources and Hydropower Engineering , Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03A期837-841,共5页
A model of fuzzy comprehensive evaluation for water saving irrigation system (WSIS) decision making is proposed based on establishing an index system affected by six kinds of basic factors including qualitative and qu... A model of fuzzy comprehensive evaluation for water saving irrigation system (WSIS) decision making is proposed based on establishing an index system affected by six kinds of basic factors including qualitative and quantitative indexes. The object function of WSIS is set up by using the concept of fuzzy membership degree, it is to transform characteristic vector matrix into unify membership matrix and extending the least square method to the least of weighted distance square. The optimum weighted membership degree and the inferior weighted membership degree are used to solve the object function. This method effective solves the problem of classify for fuzzy attributive indexes and the problem of optimum for the set of different attributive indexes. A case study shows that the fuzzy comprehensive evaluation model is reasonable and effective in decision making for water saving irrigation system planning. 展开更多
关键词 water saving irrigation system (WSIS) decision making fuzzy comprehensive evaluation (FCE) index system fuzzy membership degree
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AN IMPROVED ALGORITHM FOR SUPERVISED FUZZY C-MEANS CLUSTERING OF REMOTELY SENSED DATA 被引量:1
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作者 ZHANG Jingxiong Roger P Kirby 《Geo-Spatial Information Science》 2000年第1期39-44,共6页
This paper describes an improved algorithm for fuzzy c-means clustering of remotely sensed data, by which the degree of fuzziness of the resultant classification is de- creased as comparing with that by a conventional... This paper describes an improved algorithm for fuzzy c-means clustering of remotely sensed data, by which the degree of fuzziness of the resultant classification is de- creased as comparing with that by a conventional algorithm: that is, the classification accura- cy is increased. This is achieved by incorporating covariance matrices at the level of individual classes rather than assuming a global one. Empirical results from a fuzzy classification of an Edinburgh suburban land cover confirmed the improved performance of the new algorithm for fuzzy c-means clustering, in particular when fuzziness is also accommodated in the assumed reference data. 展开更多
关键词 remotely sensed data (images) CLASSIFICATION fuzzyc-means clustering fuzzy membership values (FMVs) Mahalanobis distances covariance matrix
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Fuzzy-GA based algorithm for optimal placement and sizing of distribution static compensator (DSTATCOM) for loss reduction of distribution network considering reconfiguration 被引量:1
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作者 Mohammad Mohammadi Mahyar Abasi A.Mohammadi Rozbahani 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期245-258,共14页
This work presents a fuzzy based methodology for distribution system feeder reconfiguration considering DSTATCOM with an objective of minimizing real power loss and operating cost. Installation costs of DSTATCOM devic... This work presents a fuzzy based methodology for distribution system feeder reconfiguration considering DSTATCOM with an objective of minimizing real power loss and operating cost. Installation costs of DSTATCOM devices and the cost of system operation, namely, energy loss cost due to both reconfiguration and DSTATCOM placement, are combined to form the objective function to be minimized. The distribution system tie switches, DSTATCOM location and size have been optimally determined to obtain an appropriate operational condition. In the proposed approach, the fuzzy membership function of loss sensitivity is used for the selection of weak nodes in the power system for the placement of DSTATCOM and the optimal parameter settings of the DFACTS device along with optimal selection of tie switches in reconfiguration process are governed by genetic algorithm(GA). Simulation results on IEEE 33-bus and IEEE 69-bus test systems concluded that the combinatorial method using DSTATCOM and reconfiguration is preferable to reduce power losses to 34.44% for 33-bus system and to 45.43% for 69-bus system. 展开更多
关键词 distribution FACTS (DFACTS) distribution static compensator (DSTATCOM) network reconfiguration genetic algorithm fuzzy membership function power loss reduction
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Research on trend prediction of component stock in fuzzy time series based on deep forest 被引量:1
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作者 Peng Li Hengwen Gu +1 位作者 Lili Yin Benling Li 《CAAI Transactions on Intelligence Technology》 SCIE EI 2022年第4期617-626,共10页
With the continuous development of machine learning and the increasing complexity of financial data analysis,it is more popular to use models in the field of machine learning to solve the hot and difficult problems in... With the continuous development of machine learning and the increasing complexity of financial data analysis,it is more popular to use models in the field of machine learning to solve the hot and difficult problems in the financial industry.To improve the effectiveness of stock trend prediction and solve the problems in time series data processing,this paper combines the fuzzy affiliation function with stock-related technical indicators to obtain nominal data that can widely reflect the constituent stocks in the case of time series changes by analysing the S&P 500 index.Meanwhile,in order to optimise the current machine learning algorithm in which the setting and adjustment of hyperparameters rely too much on empirical knowledge,this paper combines the deep forest model to train the stock data separately.The experimental results show that(1)the accuracy of the extreme random forest and the accuracy of the multi-grain cascade forest are both higher than that of the gated recurrent unit(GRU)model when the un-fuzzy index-adjusted dataset is used as features for input,(2)the accuracy of the extreme random forest and the accuracy of the multigranular cascade forest are improved by using the fuzzy index-adjusted dataset as features for input,(3)the accuracy of the fuzzy index-adjusted dataset as features for inputting the extreme random forest is improved by 18.89% compared to that of the un-fuzzy index-adjusted dataset as features for inputting the extreme random forest and(4)the average accuracy of the fuzzy index-adjusted dataset as features for inputting multi-grain cascade forest increased by 5.67%. 展开更多
关键词 deep forest fuzzy membership function price pattern time series trend forecast
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Delayed recognition:recent developments and a proposal to study this phenomenon as a fuzzy concept 被引量:1
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作者 Ronald Rousseau 《Journal of Data and Information Science》 CSCD 2018年第3期1-13,共13页
Purpose:New developments in the study of delayed recognition are discussed.Design/methodology/approach:Based on these new developments a method is proposed to characterize delayed recognition as a fuzzy concept.Findin... Purpose:New developments in the study of delayed recognition are discussed.Design/methodology/approach:Based on these new developments a method is proposed to characterize delayed recognition as a fuzzy concept.Findings:A benchmark value of 0.333 corresponding with linear growth is obtained.Moreover,a case is discovered in which an expert found delayed recognition several years before citation analysis could discover this phenomenon.Research limitations:As all citation studies also this one is database dependent.Practical implications:Delayed recognition is turned into a fuzzy concept.Originality/value:The article presents a new way of studying delayed recognition. 展开更多
关键词 Delayed recognition Sleeping beauty Hibernators fuzzy membership function
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Fuzzy Multi-Objective Decision Model of Supplier Selection with Preference Information 被引量:1
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作者 Chen Zhixiang School of Management, Zhongshan University, Guangzhou 510275, P. R. China Ma Shihua & Chen Rongqiu School of Management, Huazhong University of Science & Technology, Wuhan 430074, R R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第1期34-41,共8页
Supplier selection is a multi-objective decision problem, which must be considered many objectives, some objectives are qualitative, and others are quantitative. Meanwhile, manufacturer has preference for different su... Supplier selection is a multi-objective decision problem, which must be considered many objectives, some objectives are qualitative, and others are quantitative. Meanwhile, manufacturer has preference for different suppliers. In this paper, a new multi-objective decision model with preference information of supplier is established. A practical example of supplier selection problem utilizing this model is studied. The result demonstrates the feasibility and effectiveness of the methods proposed in the paper. 展开更多
关键词 MULTI-OBJECTIVE Supplier selection fuzzy membership degree.
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A Fuzzy Cluster and Retinex Theory-based Variation Model for Inhomogenous Image Segmentation
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作者 SUN Meng-xuan LUO Qun-nv +1 位作者 MIN Li-hua FENG Can 《火力与指挥控制》 CSCD 北大核心 2021年第10期39-46,53,共9页
A variational inhomogeneous image segmentation model based on fuzzy membership functions and Retinex theory is proposed by introducing the fuzzy membership function.The existence of the solution of the proposed model ... A variational inhomogeneous image segmentation model based on fuzzy membership functions and Retinex theory is proposed by introducing the fuzzy membership function.The existence of the solution of the proposed model is proved theoretically.A valid algorithm is designed to make numerical solution of the model under the framework of alternating minimization.The last experimental results show that the model can make segmentation of the real image with intensity inhomogeneity effectively. 展开更多
关键词 image segmentation intensity inhomogeneity fuzzy membership Retinex theory alter-nating minimization
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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 random set theory DATA fuzzy evidence fuzzy membership functions qualitative measurement model.
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Fuzzy stochastic damage mechanics(FSDM) based on fuzzy auto-adaptive control theory
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作者 Ya-jun WANG Wo-hua ZHANG +1 位作者 Chu-han ZHANG Feng JIN 《Water Science and Engineering》 EI CAS 2012年第2期230-242,共13页
In order to fully interpret and describe damage mechanics, the origin and development of fuzzy stochastic damage mechanics were introduced based on the analysis of the harmony of damage, probability, and fuzzy members... In order to fully interpret and describe damage mechanics, the origin and development of fuzzy stochastic damage mechanics were introduced based on the analysis of the harmony of damage, probability, and fuzzy membership in the interval of [0,1]. In a complete normed linear space, it was proven that a generalized damage field can be simulated through β probability distribution. Three kinds of fuzzy behaviors of damage variables were formulated and explained through analysis of the generalized uncertainty of damage variables and the establishment of a fuzzy functional expression. Corresponding fuzzy mapping distributions, namely, the half-depressed distribution, swing distribution, and combined swing distribution, which can simulate varying fuzzy evolution in diverse stochastic damage situations, were set up. Furthermore, through demonstration of the generalized probabilistic characteristics of damage variables, the cumulative distribution function and probability density function of fuzzy stochastic damage variables, which show β probability distribution, were modified according to the expansion principle. The three-dimensional fuzzy stochastic damage mechanical behaviors of the Longtan rolled-concrete dam were examined with the self-developed fuzzy stochastic damage finite element program. The statistical correlation and non-normality of random field parameters were considered comprehensively in the fuzzy stochastic damage model described in this paper. The results show that an initial damage field based on the comprehensive statistical evaluation helps to avoid many difficulties in the establishment of experiments and numerical algorithms for damage mechanics analysis. 展开更多
关键词 β probability distribution fuzzy membership of damage variable fuzzy auto-adaptive theory fuzzy stochastic finite element method fuzzy stochastic damage
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Assessment of drought hazard,vulnerability and risk in Iran using GIS techniques 被引量:1
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作者 Esmail HEYDARI ALAMDARLOO Hassan KHOSRAVI +1 位作者 Sahar NASABPOUR Ahmad GHOLAMI 《Journal of Arid Land》 SCIE CSCD 2020年第6期984-1000,共17页
The drought has enormous adverse effects on agriculture,water resources and environment,and causes damages around the world.Drought risk assessment and prioritization of drought management can help decision makers and... The drought has enormous adverse effects on agriculture,water resources and environment,and causes damages around the world.Drought risk assessment and prioritization of drought management can help decision makers and planners to manage the adverse effects of drought.This paper aims to determine the risk of drought in Iran.At the first stage,standardized precipitation index(SPI)was calculated for the period 1981–2016.Then the probability map of different drought classes or drought hazard probability map were prepared.After that the indicator-based vulnerability assessment method was used to determine the drought vulnerability index.Five indices including climate,topography,waterway density,land use and groundwater resources were chosen as the most critical factors of drought in Iran and followed by the analytical hierarchy process questionnaire,the weights of each index were obtained based on expert opinions.Fuzzy membership maps of each index and sub-index were prepared using ArcGIS software.The drought vulnerability map of Iran was plotted using these weights and maps of each indicator.Finally,the drought risk map of Iran was provided by multiplying drought hazard and vulnerability maps.According to the 43-completed questionnaires by experts,climate index has the highest vulnerability to drought.Climate does not have an important role in drought hazard index,but it is the most crucial factor to classified drought vulnerability index.The results showed that central,northeast,southeast and west parts of Iran are at high risks of drought.There are regions with different risks in Iran due to unusual weather and climatic conditions.We realized that the climate and the groundwater situation is almost the same in the central,east and south parts of Iran,because the land use plays a crucial role in the drought vulnerability and risk in these areas.The drought risk decreases from the center of Iran to the southwest and northwest. 展开更多
关键词 climate map standardized precipitation index analytical hierarchy process fuzzy membership WEIGHT
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A Support Vector Machine-based Evaluation Model of Customer Satisfaction Degree in Logistics
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作者 孙华丽 谢剑英 《Journal of Donghua University(English Edition)》 EI CAS 2007年第4期519-522,528,共5页
This paper presents a novel evaluation model of the customer satisfaction degree (CSD) in logistics based on support vector machine (SVM). Firstly, the relation between the suppliers and the customers is analyzed.... This paper presents a novel evaluation model of the customer satisfaction degree (CSD) in logistics based on support vector machine (SVM). Firstly, the relation between the suppliers and the customers is analyzed. Seondly, the evaluation index system and fuzzy quantitative methods are provided. Thirdly, the CSD evaluation system including eight indexes and three ranks based on one-against-one mode of SVM is built, last simulation experint is presented to illustrate the theoretical results. 展开更多
关键词 LOGISTICS Evaluation model fuzzy membership function Pairuise comparison Support vector machine Customer satisfaction degree
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