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Confined seepage analysis of saturated soils using fuzzy fields
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作者 Nataly A.Manque Kok-Kwang Phoon +2 位作者 Yong Liu Marcos A.Valdebenito Matthias G.R.Faes 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1302-1320,共19页
Seepage refers to the flow of water through porous materials.This phenomenon has a crucial role in dam,slope,excavation,tunnel,and well design.Performing seepage analysis usually is a challenging task,as one must cope... Seepage refers to the flow of water through porous materials.This phenomenon has a crucial role in dam,slope,excavation,tunnel,and well design.Performing seepage analysis usually is a challenging task,as one must cope with the uncertainty associated with the parameters such as the hydraulic conductivity in the horizontal and vertical directions that drive this phenomenon.However,at the same time,the data on horizontal and vertical hydraulic conductivities are typically scarce in spatial resolution.In this context,so-called non-traditional approaches for uncertainty quantification(such as intervals and fuzzy variables)offer an interesting alternative to classical probabilistic methods,since they have been shown to be quite effective when limited information on the governing parameters of a phenomenon is available.Therefore,the main contribution of this study is the development of a framework for conducting seepage analysis in saturated soils,where uncertainty associated with hydraulic conductivity is characterized using fuzzy fields.This method to characterize uncertainty extends interval fields towards the domain of fuzzy numbers.In fact,it is illustrated that fuzzy fields are an effective tool for capturing uncertainties with a spatial component,since they allow one to account for available physical measurements.A case study in confined saturated soil shows that with the proposed framework,it is possible to quantify the uncertainty associated with seepage flow,exit gradient,and uplift force effectively. 展开更多
关键词 fuzzy fields Interval fields Seepage analysis Hydraulic conductivity Spatial uncertainty
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Enhanced BDS four-frequency cycle slip detection and repair using fuzzy clustering analysis
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作者 Jinfeng Yuan Xiaoning Su Yuzhao Li 《Geodesy and Geodynamics》 2025年第4期439-453,共15页
Cycle slip detection and repair is one of the key technologies for GNSS high-precision positioning.We introduce an enhanced methodology for detecting and repairing BDS four-frequency cycle slips,utilizing fuzzy cluste... Cycle slip detection and repair is one of the key technologies for GNSS high-precision positioning.We introduce an enhanced methodology for detecting and repairing BDS four-frequency cycle slips,utilizing fuzzy clustering analysis.Firstly,based on fuzzy clustering analysis,the optimal combinations for the BDS four-frequency,including extra-wide lane(EWL),wide lane(WL),and narrow lane(NL),were selected.Secondly,the feasibility of this method was verified using actual static and dynamic observation data,and different types of cycle slips were simulated for further validation.Meanwhile,the proposed method was compared with the classical Turbo-Edit method through experiments.Finally,cycle slips were repaired using the least squares method.According to the experimental results,the optimal geometry-free phase combinations(-2,2,1,-1),(1,-1,1,-1),(3,2,-2,-3),and the pseudo-range phase combination(-1,1,1,-1),selected based on fuzzy clustering analysis,were used for cycle slip detection.The proposed method accurately detected small,large,and specific cycle slips simulated in the actual data.Compared with the Turbo-Edit method,the proposed methodwas able to detect specific cycle slips that Turbo-Edit could not.It is worth noting that during the repair process,the coefficients of the combined observation values are integers,preserving the integer cycle characteristic of the observation values,which allows cycle slips to be fixed directly,eliminating the need for complex searching procedures.Consequently,by enhancing the precision and reliability of the detection of BDS four-frequency cycle slips,our proposed method provides the support for the high-precision localization of BDS multi-frequency observations. 展开更多
关键词 BDS four-frequency Cycle slip detection and repair fuzzy clustering analysis Geometry-free phase combinations Pseudo-range phase combination
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Application of entropy-based fuzzy matter-element analysis in seepage monitoring of RCC dam
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作者 Chongshi GU Zhijun ZHANG +1 位作者 Xin CAI Yue HOU 《Frontiers of Structural and Civil Engineering》 SCIE EI 2011年第1期105-111,共7页
Taking account of the fuzzy results of the seepage monitoring analysis of roller compacted concrete(RCC)dam and uncertainties of the individual indicator evaluation,the fuzzy matter-element model of seepage monitoring... Taking account of the fuzzy results of the seepage monitoring analysis of roller compacted concrete(RCC)dam and uncertainties of the individual indicator evaluation,the fuzzy matter-element model of seepage monitoring of RCC dam analysis has been established with the use of the fuzzy matter-element analysis theory and the concept of euclid approach degree.The use of entropy theory can calculate the weighting factor through the disorder utility values of the information reflected by the data itself,which can effectively avoid the problems of weight distribution and uncertainties of subjective judgments of the seepage monitoring analysis of roller compacted concrete dam.And further the example shows that the analysis of entropy-based fuzzy matter-element analysis model of the seepage monitoring of roller compacted concrete dam is in accordance with the actual situation,which verifies the effectiveness of the method. 展开更多
关键词 information entropy fuzzy matter-element roller compacted concrete(RCC)dam seepage analysis
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Assessment of Carboniferous Volcanic Horizontal Wells after Fracturing Based on Gray Correlation,Hierarchical Analysis and Fuzzy Evaluation
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作者 Junwei Han Guohua Li +5 位作者 Wu Zhong Yuchen Yang Maoheng Li Zhiwei Chen Ruichang Ge Lijuan Huang 《Fluid Dynamics & Materials Processing》 EI 2024年第12期2757-2773,共17页
A comprehensive method to evaluate the factors affecting the production capacity of horizontal wells in Carboniferous volcanic rocks after fracturing is investigated.A systematic approach combining gray correlation an... A comprehensive method to evaluate the factors affecting the production capacity of horizontal wells in Carboniferous volcanic rocks after fracturing is investigated.A systematic approach combining gray correlation analysis,hierarchical analysis and fuzzy evaluation is proposed.In particular,first the incidence of reservoir properties and fracturing parameters on production capacity is assessed.These parameters include reservoir base geological parameters(porosity,permeability,oil saturation,waterproof height)as well as engineering parameters(fracture halflength,fracture height,fracture conductivity,fracture distance).Afterwards,a two-by-two comparison judgment matrix of sensitive parameters is constructed by means of hierarchical analysis,and the weighting coefficients of the factors are determined,where oil saturation,fracture conductivity and fracture half-length are weighted higher.Finally,the horizontal wells in the target block are categorized in terms of production capacity based on the fuzzy evaluation method,and split accordingly into high-producing,relatively high-producing,medium-producing and low-producing wells.Such a categorization is intended to provide parametric guidance for reservoir fracturing and modification. 展开更多
关键词 Fracturing parameter horizontal well grey correlation hierarchical analysis fuzzy evaluation productivity evaluation
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Flood Risk Modelling Using the HFPA (Hierarchical Fuzzy Process Analysis) Method: Example of the City of Thies, Senegal
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作者 Seybatou Dieye Mapathé Ndiaye +1 位作者 Diogoye Diouf Makhaly Ba 《International Journal of Geosciences》 2024年第12期1064-1086,共23页
Based on the perception of flood risk factors derived from the lessons learned by the main stakeholders, namely the members of the National Emergency Response Plan (ORSEC) and the people affected by floods in the stud... Based on the perception of flood risk factors derived from the lessons learned by the main stakeholders, namely the members of the National Emergency Response Plan (ORSEC) and the people affected by floods in the study area (Thies, Senegal), this work consists of modelling the flood risk using Hierarchical Process Analysis (HPA). This modelling made it possible to determine the coherence index (CI) and the coherence ratio, which were evaluated respectively at 0.27% and 5% according to the perception of the members of the ORSEC Plan, and at 0.28% and 5% according to the perception of the disaster victims. These results show that the working approach is coherent and acceptable. We then carried out Hierarchical Fuzzy Process Analysis (HFPA), an extension of HFPA, which seeks to minimize the margins of error. FPHA uses fuzzification of perception contributions, interference rules and defuzzification to determine the Net Flood Risk Index (NFRI). Integrated with ArcGIS software, the NFRI is used to generate flood risk maps that reveal a high risk of vulnerability of the main outlets occupied by human settlements. 展开更多
关键词 FLOOD HAZARD VULNERABILITY FACTOR Risk Coherence Index Coherence Ratio Hierarchical analysis of fuzzy Processes Thies
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Dynamic Analysis of Customer Demand Based on Intuitionistic Fuzzy Number in Product Planning
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作者 Yongguang Yi Zengqiang Wang 《Proceedings of Business and Economic Studies》 2024年第5期127-131,共5页
To address the fuzziness and variability in determining customer demand importance,a dynamic analysis method based on intuitionistic fuzzy numbers is proposed.First,selected customers use intuitionistic fuzzy numbers ... To address the fuzziness and variability in determining customer demand importance,a dynamic analysis method based on intuitionistic fuzzy numbers is proposed.First,selected customers use intuitionistic fuzzy numbers to represent the importance of each demand.Then,the preference information is aggregated using customer weights and time period weights through the intuitionistic fuzzy ordered weighted average operator,yielding a dynamic vector of the subjective importance of the demand index.Finally,the feasibility of the proposed method is demonstrated through an application example of a vibrating sorting screen. 展开更多
关键词 Quality function deployment Customer demand Intuitionistic fuzzy number Dynamic analysis method
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Evaluation on Urban Land Ecological Security Based on the PSR Model and Matter-Element Analysis: A Case Study of Zhuhai, Guangdong, China 被引量:4
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作者 LI Shuang 《Journal of Landscape Research》 2019年第3期82-88,92,共8页
As one of the Special Economic Zones since the reform and opening up, Zhuhai has developed during the past 30 years. Its economic development, industrial structure and ecological environment have undergone great chang... As one of the Special Economic Zones since the reform and opening up, Zhuhai has developed during the past 30 years. Its economic development, industrial structure and ecological environment have undergone great changes. Research on changes in Zhuhai’s land ecological security is of great significance. Using relevant data from 2007-2012, this study established a land ecological security assessment system based on the PSR conceptual framework model. The system contained 18 indicators from 3 aspects according to the concrete features of Zhuhai. Then we used the matterelement analysis and the improved entropy weight to analyze and evaluate the land ecological security of Zhuhai. The results showed that: from 2007 to 2012, the levels of the land ecological security of Zhuhai were “secure”, and the value increased year by year;as the land ecological security response value increased, Zhuhai was capable of solving land ecosystem problems. However, it should be noted that the structure of land ecosystem in Zhuhai has not formed and that rapid expansion of construction land has caused the shortage of cultivated land and other issues. Measures should be taken to control the construction area, improve land intensive utilization and improve the land ecological security. 展开更多
关键词 Land ECOLOGICAL security PSR model matter-element analysis Improved ENTROPY WEIGHT Zhuhai
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Evaluation of the Strategic Tolerance Human Resource Management Based on Matter-Element Analysis Method 被引量:2
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作者 高宏 《Journal of Donghua University(English Edition)》 EI CAS 2011年第5期533-538,共6页
The main features and connotation of the tolerance human resource management based on strategy are analyzed and summarized. The theory and method of systematic engineering is used to build the evaluation index systems... The main features and connotation of the tolerance human resource management based on strategy are analyzed and summarized. The theory and method of systematic engineering is used to build the evaluation index systems for the tolerance human resource management. On the basis of it, by using the theory of matter-element analysis, the matter-element models are formulated for the evaluation of the tolerance human resource management. Regarding annual tolerance human resource management as the object of matter-dement, the tolerance human resource :management for two years are analyzed and evaluated through using the matter. element models proposed. A ease study is carried out and the satisfactory results are obtained. A new scientific methed is provided for the evaluation of human resource management based on strategy. 展开更多
关键词 matter-element analysis strategy tolerance human resource management EVALUATION FAIR SHARE
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Integrated Evaluation of Air Traffic Controller Workload Based on Matter-Element Analysis 被引量:1
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作者 张明 韩松臣 《Journal of Southwest Jiaotong University(English Edition)》 2008年第2期164-169,共6页
A model for evaluating the controller workload was presented based on matter-element analysis, particularly from a mansystem engineering perspective. On the basis of a questionnaire survey, 18 kinds of indexes which i... A model for evaluating the controller workload was presented based on matter-element analysis, particularly from a mansystem engineering perspective. On the basis of a questionnaire survey, 18 kinds of indexes which influence the controller workload were determined. By establishing the classical field and node field of the controller workload, the correlation function of the controller workload grade was obtained; then the correlation degree and estimated grade of controller workload were given. A case study verifies the feasibility of the proposed evaluation method. 展开更多
关键词 Air traffic control Controller workload matter-element analysis EXTENICS CORRELATION
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Expert Anti-Evaluation Model Based on Matter-Element Analysis in Fund Project Peer-Review System
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作者 Haifeng Li Yanzhong Dang 《Intelligent Information Management》 2010年第3期227-231,共5页
The article analyses several key issues which restrict the effectiveness of fund project peer review work. It analyses the evaluating theory and matter-element theory to access the expert anti-evaluation model, and al... The article analyses several key issues which restrict the effectiveness of fund project peer review work. It analyses the evaluating theory and matter-element theory to access the expert anti-evaluation model, and also studies the expert anti-evaluation index system to support the anti-evaluation method. The practical basis is the true score data of the experts which is collected from the actual anti-evaluation in Liaoning province science and technology fund project peer review system. With the practical experience of the actual project, we prove that the expert index system anti-evaluation model and expert anti-evaluation method can improve the fund project peer review work and play a positive role for the peer review work and also make the review work more scientific and more rational. 展开更多
关键词 Anti-Evaluation Model matter-element analysis Index SYSTEM Comprehensive Evaluation PEER Review
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ESTIMATION METHOD FOR AIRCRAFT SIMILARITY BASED ON FUZZY THEORY AND GREY INCIDENCE ANALYSIS 被引量:4
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作者 李永平 陈闵叶 刘明 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第3期194-198,共5页
An estimation method for aircraft similarity based on fuzzy theory and grey incidence analysis is presented. This estimation method is made up of the triangular fuzzy transforming model of linguistic variables and the... An estimation method for aircraft similarity based on fuzzy theory and grey incidence analysis is presented. This estimation method is made up of the triangular fuzzy transforming model of linguistic variables and the method of grey incidence analysis. Nine feature attributes of aircraft are selected to estimate the similarity between the new aircraft and the existing aircraft. A new aircraft X and other six existing aircrafts are taken as examples. Analyses show that similarity estimation results obtained from the method are in accordance with practice. 展开更多
关键词 aircraft similarity fuzzy theory grey incidence analysis
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FUZZY WITHIN-CLASS MATRIX PRINCIPAL COMPONENT ANALYSIS AND ITS APPLICATION TO FACE RECOGNITION 被引量:3
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作者 朱玉莲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第2期141-147,共7页
Matrix principal component analysis (MatPCA), as an effective feature extraction method, can deal with the matrix pattern and the vector pattern. However, like PCA, MatPCA does not use the class information of sampl... Matrix principal component analysis (MatPCA), as an effective feature extraction method, can deal with the matrix pattern and the vector pattern. However, like PCA, MatPCA does not use the class information of samples. As a result, the extracted features cannot provide enough useful information for distinguishing pat- tern from one another, and further resulting in degradation of classification performance. To fullly use class in- formation of samples, a novel method, called the fuzzy within-class MatPCA (F-WMatPCA)is proposed. F-WMatPCA utilizes the fuzzy K-nearest neighbor method(FKNN) to fuzzify the class membership degrees of a training sample and then performs fuzzy MatPCA within these patterns having the same class label. Due to more class information is used in feature extraction, F-WMatPCA can intuitively improve the classification perfor- mance. Experimental results in face databases and some benchmark datasets show that F-WMatPCA is effective and competitive than MatPCA. The experimental analysis on face image databases indicates that F-WMatPCA im- proves the recognition accuracy and is more stable and robust in performing classification than the existing method of fuzzy-based F-Fisherfaces. 展开更多
关键词 face recognition principal component analysis (PCA) matrix pattern PCA(MatPCA) fuzzy K-nearest neighbor(FKNN) fuzzy within-class MatPCA(F-WMatPCA)
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Stability analysis for affine fuzzy system based on fuzzy Lyapunov functions
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作者 柳善建 沈炯 +1 位作者 刘西陲 李益国 《Journal of Southeast University(English Edition)》 EI CAS 2011年第3期295-299,共5页
An analysis method based on the fuzzy Lyapunov functions is presented to analyze the stability of the continuous affine fuzzy systems. First, a method is introduced to deal with the consequent part of the fuzzy local ... An analysis method based on the fuzzy Lyapunov functions is presented to analyze the stability of the continuous affine fuzzy systems. First, a method is introduced to deal with the consequent part of the fuzzy local model. Thus, the stability analysis method of the homogeneous fuzzy system can be used for reference. Stability conditions are derived in terms of linear matrix inequalities based on the fuzzy Lyapunov functions and the modified common Lyapunov functions, respectively. The results demonstrate that the stability result based on the fuzzy Lyapunov functions is less conservative than that based on the modified common Lyapunov functions via numerical examples. Compared with the method which does not expand the consequent part, the proposed method is simpler but its feasible region is reduced. Finally, in order to expand the application of the fuzzy Lyapunov functions, the piecewise fuzzy Lyapunov function is proposed, which can be used to analyze the stability for triangular or trapezoidal membership functions and obtain the stability conditions. A numerical example validates the effectiveness of the proposed approach. 展开更多
关键词 affine fuzzy system stability analysis linear matrix inequalities fuzzy Lyapunov function
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基于Fuzzy Matter-Element模型的电力上市公司财务核心竞争能力评价
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作者 张艳 陈兆江 杨宏伟 《中国管理信息化》 2010年第14期31-33,共3页
鉴于电力上市公司财务核心竞争能力评价的复杂性以及单项指标评价结果的不相容性,本文在模糊物元分析的基础上,将熵权的理论方法与海明贴近度的概念相结合,建立了电力上市公司财务核心竞争能力评价的模糊物元模型。把不同电力企业作为... 鉴于电力上市公司财务核心竞争能力评价的复杂性以及单项指标评价结果的不相容性,本文在模糊物元分析的基础上,将熵权的理论方法与海明贴近度的概念相结合,建立了电力上市公司财务核心竞争能力评价的模糊物元模型。把不同电力企业作为物元的事物,以它们的各项评价指标及相应的模糊量值构造模糊物元,通过计算与理想模糊物元之间的海明贴近度,实现对上市电力公司财务核心竞争能力的综合评价。 展开更多
关键词 财务核心竞争能力 模糊物元(fuzzy matter-element) 熵权(Entropy weight) 海明贴近度(Hamming ap-proach degree)
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Assessment of gas and dust explosion in coal mines by means of fuzzy fault tree analysis 被引量:13
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作者 Shulei Shi Bingyou Jiang Xiangrui Meng 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第6期991-998,共8页
During the past decade, coal dust and gas explosions have been the most two serious types of disasters in China, threatening the lives of miners and causing significant losses in terms of national property. In this pa... During the past decade, coal dust and gas explosions have been the most two serious types of disasters in China, threatening the lives of miners and causing significant losses in terms of national property. In this paper, an evaluation model of coal dust and gas explosions was constructed based on a fuzzy fault tree by taking the Xingli Coal Mine as a research site to identify the risk factors of coal dust and gas explosions.Furthermore, the hazards associated with such explosions were evaluated for this particular coal mine.After completing an on-site investigation, the fuzzy probabilities of basic events were obtained through expert scoring, and these expert opinions were then aggregated as trapezoidal fuzzy numbers to calculate the degrees of importance of all basic events. Finally, these degrees of importance were sorted. According to the resulting order, the basic events with higher probabilities were determined to identify key hazards in the daily safety management of this particular coal mine. Moreover, effective measures for preventing gas and coal dust explosions were derived. The fuzzy fault tree analysis method is of high significance in the analysis of accidental coal mine explosions and provides theoretical guidance for improving the efficiency of coal mine safety management in a scientific and feasible manner. 展开更多
关键词 Coal DUST explosion Gas explosion fuzzy FAULT TREE analysis(FFTA) Trapezoidal fuzzy NUMBERS
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Water quality evaluation based on improved fuzzy matter-element method 被引量:23
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作者 Dongjun Liu Zhihong Zou 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第7期1210-1216,共7页
For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. Th... For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. The coefficient of variation of each indicator is used to determine the weight instead of traditional calculating superscales method. On the other hand, fuzzy matter-elements are constructed, and normal membership degrees are used instead of traditional trapezoidal ones. The composite fuzzy matter-elements with associated coefficient are constructed through associated transformation. The levels of natural water quality are determined according to the principle of maximum correlation. The improved fuzzy matter-element evaluation method is applied to evaluate water quality of the Luokou mainstream estuary at the first ten weeks in 2011 with the coefficient of variatiola method determining the weights. Water quality of Luokou mainstream estuary is dropping from level I to level II. The results of the improved evaluation method are basically the same as the official water quality. The variation coefficient method can reduce the workload, and overcome the adverse effects from abnormal values, compared with the traditional calculating superscales method. The results of improved fuzzy matter- element evaluation method are more credible than the ones of the traditional evaluation method. The improved evaluation method can use information of monitoring data more scientifically and comprehensively, and broaden a new evaluation method for water quality assessment. 展开更多
关键词 water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership Key words: water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership
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Fuzzy data envelopment analysis approach based on sample decision making units 被引量:11
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作者 Muren Zhanxin Ma Wei Cui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第3期399-407,共9页
The conventional data envelopment analysis (DEA) measures the relative efficiencies of a set of decision making units with exact values of inputs and outputs. In real-world prob- lems, however, inputs and outputs ty... The conventional data envelopment analysis (DEA) measures the relative efficiencies of a set of decision making units with exact values of inputs and outputs. In real-world prob- lems, however, inputs and outputs typically have some levels of fuzziness. To analyze a decision making unit (DMU) with fuzzy input/output data, previous studies provided the fuzzy DEA model and proposed an associated evaluating approach. Nonetheless, numerous deficiencies must still be improved, including the α- cut approaches, types of fuzzy numbers, and ranking techniques. Moreover, a fuzzy sample DMU still cannot be evaluated for the Fuzzy DEA model. Therefore, this paper proposes a fuzzy DEA model based on sample decision making unit (FSDEA). Five eval- uation approaches and the related algorithm and ranking methods are provided to test the fuzzy sample DMU of the FSDEA model. A numerical experiment is used to demonstrate and compare the results with those obtained using alternative approaches. 展开更多
关键词 fuzzy mathematical programming sample decision making unit fuzzy data envelopment analysis EFFICIENCY α-cut.
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A precise tidal prediction mechanism based on the combination of harmonic analysis and adaptive network-based fuzzy inference system model 被引量:6
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作者 ZHANG Zeguo YIN Jianchuan +2 位作者 WANG Nini HU Jiangqiang WANG Ning 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第11期94-105,共12页
An efficient and accurate prediction of a precise tidal level in estuaries and coastal areas is indispensable for the management and decision-making of human activity in the field wok of marine engineering. The variat... An efficient and accurate prediction of a precise tidal level in estuaries and coastal areas is indispensable for the management and decision-making of human activity in the field wok of marine engineering. The variation of the tidal level is a time-varying process. The time-varying factors including interference from the external environment that cause the change of tides are fairly complicated. Furthermore, tidal variations are affected not only by periodic movement of celestial bodies but also by time-varying interference from the external environment. Consequently, for the efficient and precise tidal level prediction, a neuro-fuzzy hybrid technology based on the combination of harmonic analysis and adaptive network-based fuzzy inference system(ANFIS)model is utilized to construct a precise tidal level prediction system, which takes both advantages of the harmonic analysis method and the ANFIS network. The proposed prediction model is composed of two modules: the astronomical tide module caused by celestial bodies’ movement and the non-astronomical tide module caused by various meteorological and other environmental factors. To generate a fuzzy inference system(FIS) structure,three approaches which include grid partition(GP), fuzzy c-means(FCM) and sub-clustering(SC) are used in the ANFIS network constructing process. Furthermore, to obtain the optimal ANFIS based prediction model, large numbers of simulation experiments are implemented for each FIS generating approach. In this tidal prediction study, the optimal ANFIS model is used to predict the non-astronomical tide module, while the conventional harmonic analysis model is used to predict the astronomical tide module. The final prediction result is performed by combining the estimation outputs of the harmonious analysis model and the optimal ANFIS model. To demonstrate the applicability and capability of the proposed novel prediction model, measured tidal level samples of Fort Pulaski tidal station are selected as the testing database. Simulation and experimental results confirm that the proposed prediction approach can achieve precise predictions for the tidal level with high accuracy, satisfactory convergence and stability. 展开更多
关键词 tidal level prediction harmonious analysis method adaptive network-based fuzzy inference system correlation analysis
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Risk analysis of extended reach wells in the Liuhua Oilfield,South China Sea,based on comprehensive fuzzy evaluation method 被引量:6
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作者 Zhang Hui Gao Deli Hao Zhiwei 《Petroleum Science》 SCIE CAS CSCD 2009年第2期172-175,共4页
Drilling engineering has great uncertainty and it always involves huge investment and high risk. Risk analysis of extended reach drilling (ERD) is very important to prevent complex failures and to improve drilling e... Drilling engineering has great uncertainty and it always involves huge investment and high risk. Risk analysis of extended reach drilling (ERD) is very important to prevent complex failures and to improve drilling efficiency. Nowadays there are few reports on how to analyze quantitatively the drilling risk for extended reach wells (ERWs). Based on the fuzzy set theory, a comprehensive fuzzy evaluation model for analyzing risks of ERD is proposed in this paper. Well B6ERW07 is a planned 8,000-meter ERW with a high ratio of horizontal displacement (HD) to vertical depth (VD) in the Liuhua Oilfield, the South China Sea, China. On the basis of the evaluation model developed in this study, the risk for drilling Well B6ERW07 was evaluated before drilling. The evaluation result shows that the success rate of drilling this well is predicted to be 51.9%, providing important rational and scientific information for the decisionmakers. 展开更多
关键词 Extended reach well risk analysis comprehensive fuzzy evaluation weight value
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Fuzzy Risk Analysis of Harbour Engineering Investment by Hierarchy System Approach 被引量:6
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作者 Lin Shaopei and Zhang Zhongming Professor, Civil and Architectural Engineering Dept., Shanghai Jiao Tong University, Shanghai Lecturer, Civil and Architectural Engineering Dept., Shanghai Jiao Tong University, Shanghai 《China Ocean Engineering》 SCIE EI 1992年第1期87-94,共8页
The present risk analysis model of engineering investment is built by fuzzy hierarchy approach under the assumption of maximizing the revenues of the project during its whole life cycle of operation. It can reasonably... The present risk analysis model of engineering investment is built by fuzzy hierarchy approach under the assumption of maximizing the revenues of the project during its whole life cycle of operation. It can reasonably be expressed by a system evaluation analysis. As a matter of fact, the system, aimed by its system goal can be modelled by a set of factors, constitutively structured by certain links between them, to form a factorial network chart, which represents the essentials of the system behaviours, the nodes of which represent the factors concerned. The weight distribution between factors located at the same level can be determined by the eigen-value problem of a 'pair comparison' relation matrix. The weight distribution of factors at each level is successively manipulated until the fuzzy synthetic risk assessment. As an example of risk analysis of engineering investment, a harbour construction project is presented for illustration. 展开更多
关键词 risk analysis engineering economic fuzzy mathematics analytic hierarchy process
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