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模糊理论分析法在水利工程施工期的风险评价应用 被引量:8
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作者 张连凯 《水利规划与设计》 2018年第3期130-132,共3页
基于某河道防洪工程,利用改进的模糊层次法和改进的模糊二元对比分析法对其施工期的风险进行了定性和定量的分析和评价。研究结果表明:分析计算得到因素层和准则层的排序有一定差异,但两种方法对于施工期的风险评价结果具有良好的一致性... 基于某河道防洪工程,利用改进的模糊层次法和改进的模糊二元对比分析法对其施工期的风险进行了定性和定量的分析和评价。研究结果表明:分析计算得到因素层和准则层的排序有一定差异,但两种方法对于施工期的风险评价结果具有良好的一致性,前者计算精度高,计算量大,适用于大中型水利工程,后者计算精度较低,计算相对简便,一般适用于小型项目,并由此提出了水利工程在施工期的风险监督和管理方法。 展开更多
关键词 模糊理论分析 水利工程施工期 风险评价
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模糊理论分析法在水利工程施工期的风险评价应用 被引量:1
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作者 克热木·夏木西丁 《湖南水利水电》 2020年第4期103-105,共3页
文章基于国内某水利工程河道防洪工程,并使用基于模糊层次法以及模糊二元对比分析法的基础上改进而来的新型分析方法,对河道工程施工期可能存在的风险进行分析。通过分析结果可以看到,因素层与准则层的顺序存在不同,但是运用这两种分析... 文章基于国内某水利工程河道防洪工程,并使用基于模糊层次法以及模糊二元对比分析法的基础上改进而来的新型分析方法,对河道工程施工期可能存在的风险进行分析。通过分析结果可以看到,因素层与准则层的顺序存在不同,但是运用这两种分析方法对工程风险进行评价的结果是相同的,两种方法的区别在于模糊层次法的计算结果准确度非常高,而且计算量非常大,比较适合应用在一些较大型的工程之中,而模糊二元对比分析法的计算结果准确度较低,而且计算的方式比较简单,比较适合应用于一些小型项目。根据分析评价的结果文章提出了针对工程施工期风险的监督与管理的方法。 展开更多
关键词 水利工程 施工期 模糊理论分析 风险评价
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电站锅炉主要热工过程参数软测量技术研究进展 被引量:16
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作者 罗嘉 吴乐 《热力发电》 CAS 北大核心 2015年第11期1-9,13,共10页
电站锅炉某些主要热工过程参数难以实现在线实时测量,从而制约了机组的高效、经济运行。为此,本文解析了基于统计分析的主元分析法和偏最小二乘法、基于人工智能的人工神经网络(ANN)法、基于统计学习理论的支持向量机法以及模糊理论法... 电站锅炉某些主要热工过程参数难以实现在线实时测量,从而制约了机组的高效、经济运行。为此,本文解析了基于统计分析的主元分析法和偏最小二乘法、基于人工智能的人工神经网络(ANN)法、基于统计学习理论的支持向量机法以及模糊理论法的建模方法。并以球磨机负荷、煤质、风煤比、烟气含氧量、飞灰含碳量、汽包水位、主蒸汽温度、省煤器积灰、污染物排放量等参数为对象,综述了各种软测量技术的研究现状。结果显示:对于飞灰含碳量等呈非线性特征的变量,基于核主元分析(KPCA)法建立其软测量模型,效果较好;当各变量的线性关联度高时,采用偏最小二乘回归(PLSR)法建立其软测量模型更为有效;对于人工神经网络法,当实际样本空间超出训练样本空间区域时,模型输出误差较大,因此实际工业过程中需定时对基于ANN法建立的模型参数进行校正;对于支持向量机(SVM)法还无成熟的指导方法,基于经验数据则对模型精度的影响较大,最小二乘支持向量机(LS-SVM)法的建模方法与传统SVM法相比,训练时间更短,结果更具确定性,更适合工业在线建模;模糊理论法不需要被测对象的精确数学模型,但模糊系统本身不具有学习功能,如果能够将其与ANN法等人工智能方法相结合,则可提高软测量的性能。因此,软测量技术的引入,使得难以在线测量的热工过程参数监测成为可能。 展开更多
关键词 电站锅炉 热工过程参数 软测量 主元分析 偏最小二乘 神经网络 支持向量机 模糊理论法
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商务网络信息生态链价值协同创造的关键影响因素识别研究 被引量:3
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作者 张海涛 任亮 +1 位作者 刘雅姝 魏明珠 《现代情报》 CSSCI 2019年第6期16-23,58,共9页
[目的/意义]通过对商务网络信息生态链价值协同创造影响机理进行研究,识别出关键影响因素,对商务网站价值增加、顾客满意度提高以及整个生态链的价值增值有重要的参考意义,同时丰富其理论体系。[方法/过程]构建商务网络信息生态链价值... [目的/意义]通过对商务网络信息生态链价值协同创造影响机理进行研究,识别出关键影响因素,对商务网站价值增加、顾客满意度提高以及整个生态链的价值增值有重要的参考意义,同时丰富其理论体系。[方法/过程]构建商务网络信息生态链价值协同创造的过程模型,并据此建立影响因素指标体系,利用专家打分法收集原始数据,运用模糊集理论-DEMATEL法对各项因素的影响程度进行分析。[结果/结论]最终识别出顾客满意度等8项因素作为商务网络信息生态链的关键影响因素。从3个角度提出促进以及优化商务网络信息生态链价值协同创造的建议。 展开更多
关键词 商务网络 信息生态链 模糊理论-DEMATEL 关键影响因素
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电力系统故障诊断中人工智能技术的应用分析 被引量:1
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作者 丁晖 朱宁 任寅平 《通讯世界》 2020年第9期120-122,共3页
基于社会各界高度重视电网供电安全问题,将提高电力系统的运行效率作为当前重要研究课题。基于此,本文简析了人工智能技术的特点和优点,阐述了人工智能技术的应用领域及其在电力系统故障诊断中的应用现状,最后提出人工智能技术在电力系... 基于社会各界高度重视电网供电安全问题,将提高电力系统的运行效率作为当前重要研究课题。基于此,本文简析了人工智能技术的特点和优点,阐述了人工智能技术的应用领域及其在电力系统故障诊断中的应用现状,最后提出人工智能技术在电力系统故障诊断中的具体应用,以期提高电力系统故障诊断效率,确保电网事业在人工智能技术推动下健康长远发展。 展开更多
关键词 电力系统 故障诊断 人工智能技术 模糊理论法
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Multiple vehicle routing problem integrated reverse logistics with fuzzy reverse demands
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作者 李建 达庆利 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期222-227,共6页
A new type of vehicle routing problem (VRP), multiple vehicle routing problem integrated reverse logistics (MVRPRL), is studied. In this problem, there is delivery or pickup (or both) and uncertain features in t... A new type of vehicle routing problem (VRP), multiple vehicle routing problem integrated reverse logistics (MVRPRL), is studied. In this problem, there is delivery or pickup (or both) and uncertain features in the demands of the clients. The deliveries of every client as uncertain parameters are expressed as triangular fuzzy numbers. In order to describe MVRPRL, a multi-objective fuzzy programming model with credibility measure theory is constructed. Then the simulationbased tabu search algorithm combining inter-route and intra-route neighborhoods and embedded restarts are designed to solve it. Computational results show that the tabu search algorithm developed is superior to sweep algorithms and that compared with handling each on separate routes, the transportation costs can be reduced by 43% through combining pickups with deliveries. 展开更多
关键词 reverse logistics pickup and delivery credibility measure theory tabu search algorithm fuzzy simulation
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Optimization of mining method in subsea deep gold mines: A case study 被引量:7
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作者 Wei-zhang LIANG Guo-yan ZHAO +1 位作者 Hao WU Ying CHEN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第10期2160-2169,共10页
The mining method optimization in subsea deep gold mines was studied. First, an index system for subsea mining method selection was established based on technical feasibility, security status, economic benefit, and ma... The mining method optimization in subsea deep gold mines was studied. First, an index system for subsea mining method selection was established based on technical feasibility, security status, economic benefit, and management complexity. Next, an evaluation matrix containing crisp numbers and triangular fuzzy numbers(TFNs) was constructed to describe quantitative and qualitative information simultaneously. Then, a hybrid model combining fuzzy theory and the Tomada de Decis?o Interativa Multicritério(TODIM) method was proposed. Finally, the feasibility of the proposed approach was validated by an illustrative example of selecting the optimal mining method in the Sanshandao Gold Mine(China). The robustness of this approach was demonstrated through a sensitivity analysis. The results show that the proposed hybrid TODIM method is reliable and stable for choosing the optimal mining method in subsea deep gold mines and provides references for mining method optimization in other similar undersea mines. 展开更多
关键词 subsea deep mining mining method fuzzy theory hybrid TODIM method
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Composition ship collision risk based on fuzzy theory 被引量:4
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作者 CHEN Shu Rashid Ahmad +1 位作者 Byung-Gil Lee Do Hyeun Kim 《Journal of Central South University》 SCIE EI CAS 2014年第11期4296-4302,共7页
Despite of modern navigation devices, there are problems in navigation of vessels in waterways due to the geographical structures, disturbances in water, dynamic nature, and heavily environmental influenced sea traffi... Despite of modern navigation devices, there are problems in navigation of vessels in waterways due to the geographical structures, disturbances in water, dynamic nature, and heavily environmental influenced sea traffic. Even though all vessels are equipped with modern navigation devices, the accidents are reported caused by various reasons and mainly by human factor according to investigation. We propose an effective and efficient composition collision risk calculation method for finding the collision probability and avoiding the collision between ships in possible collision situations. The proposed composition collision risk calculation method at ship's position using combination of fuzzy and fuzzy comprehensive evaluation methods. The algorithm is straightforward to implement and is shown to be effective in automatic ship handling for ships involved in complex navigation situations. Experiments are carried out with indigenous data and the results show the effectiveness of the proposed approach. 展开更多
关键词 automatic ship navigation collision risk fuzzy theory
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A Fuzzy-based Adaptive Genetic Algorithm and Its Case Study in Chemical Engineering 被引量:5
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作者 杨传鑫 颜学峰 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第2期299-307,共9页
Considering that the performance of a genetic algorithm (GA) is affected by many factors and their rela-tionships are complex and hard to be described,a novel fuzzy-based adaptive genetic algorithm (FAGA) combined... Considering that the performance of a genetic algorithm (GA) is affected by many factors and their rela-tionships are complex and hard to be described,a novel fuzzy-based adaptive genetic algorithm (FAGA) combined a new artificial immune system with fuzzy system theory is proposed due to the fact fuzzy theory can describe high complex problems.In FAGA,immune theory is used to improve the performance of selection operation.And,crossover probability and mutation probability are adjusted dynamically by fuzzy inferences,which are developed according to the heuristic fuzzy relationship between algorithm performances and control parameters.The experi-ments show that FAGA can efficiently overcome shortcomings of GA,i.e.,premature and slow,and obtain better results than two typical fuzzy GAs.Finally,FAGA was used for the parameters estimation of reaction kinetics model and the satisfactory result was obtained. 展开更多
关键词 fuzzy logic controller genetic algorithm artificial immune system reaction kinetics model
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Research on the fully fuzzy time-cost trade-off based on genetic algorithms 被引量:1
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作者 JIN Chao-guang JI Zhuo-shang +2 位作者 LIN Yan ZHAO Yuan-min HUANG Zhen-dong 《Journal of Marine Science and Application》 2005年第3期18-23,共6页
It is very difficult to estimate exact values of time and cost of an activity in project scheduling process because many uncertain factors, such as weather, productivity level, human factors etc. , dynamically affect ... It is very difficult to estimate exact values of time and cost of an activity in project scheduling process because many uncertain factors, such as weather, productivity level, human factors etc. , dynamically affect them during project implementation process. A GAs-based fully fuzzy optimal time-cost trade-off model is presented based on fuzzy sets and genetic algorithms (GAs). In tihs model all parameters and variables are characteristics by fuzzy numbers. And then GAs is adopted to search for the optimal solution to this model. The method solves the time-cost trade-off problems under an uncertain environment and is proved practicable through a giving example in ship building scheduling. 展开更多
关键词 fuzzy sets ranking fuzzy number genetic algorithms time-cost trade-off
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A model to determining the remaining useful life of rotating equipment,based on a new approach to determining state of degradation 被引量:3
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作者 Saeed RAMEZANI Alireza MOINI +1 位作者 Mohamad RIAHI Adolfo Crespo MARQUEZ 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第8期2291-2310,共20页
Condition assessment is one of the most significant techniques of the equipment’s health management.Also,in PHM methodology cycle,which is a developed form of CBM,condition assessment is the most important step of th... Condition assessment is one of the most significant techniques of the equipment’s health management.Also,in PHM methodology cycle,which is a developed form of CBM,condition assessment is the most important step of this cycle.In this paper,the remaining useful life of the equipment is calculated using the combination of sensor information,determination of degradation state and forecasting the proposed health index.The combination of sensor information has been carried out using a new approach to determining the probabilities in the Dempster-Shafer combination rules and fuzzy c-means clustering method.Using the simulation and forecasting of extracted vibration-based health index by autoregressive Markov regime switching(ARMRS)method,final health state is determined and the remaining useful life(RUL)is estimated.In order to evaluate the model,sensor data provided by FEMTO-ST Institute have been used. 展开更多
关键词 remaining useful life(RUL) prognostics and health management(PHM) autoregressive markov regime switching(ARMRS) health index(HI) Dempster-Shafer theory fuzzy c-means(FCM) Kurtosis-entropy DEGRADATION
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AN ESTIMATION OF FUZZY RELIABILITY OF DISTINCT ELEMENT METHOD IN PREDICTION OF SURFACE SUBSIDENCE DUE TO COAL MINING 被引量:1
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作者 张玉卓 《Journal of Coal Science & Engineering(China)》 1998年第2期7-12,共6页
The quantitative evaluation of errors involved in a particular numerical modelling is of prime importance for the effectiveness and reliability of the method. Errors in Distinct Element Modelling are generated mainly ... The quantitative evaluation of errors involved in a particular numerical modelling is of prime importance for the effectiveness and reliability of the method. Errors in Distinct Element Modelling are generated mainly through three resources as simplification of physical model, determination of parameters and boundary conditions. A measure of errors which represent the degree of numerical solution 'close to true value' is proposed through fuzzy probability in this paper. The main objective of this paper is to estimate the reliability of Distinct Element Method in rock engineering practice by varying the parameters and boundary conditions. The accumulation laws of standard errors induced by improper determination of parameters and boundary conditions are discussed in delails. Furthermore, numerical experiments are given to illustrate the estimation of fuzzy reliability. Example shows that fuzzy reliability falls between 75%-98% when the relative standard errors of input data is under 10 %. 展开更多
关键词 RELIABILITY fuzzy sets ERRORS Distinct Element Method BALL
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Optimal design of structural parameters for shield cutterhead based on fuzzy mathematics and multi-objective genetic algorithm 被引量:12
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作者 夏毅敏 唐露 +2 位作者 暨智勇 程永亮 卞章括 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期937-945,共9页
In order to improve the strength and stiffness of shield cutterhead, the method of fuzzy mathematics theory in combination with the finite element analysis is adopted. An optimal design model of structural parameters ... In order to improve the strength and stiffness of shield cutterhead, the method of fuzzy mathematics theory in combination with the finite element analysis is adopted. An optimal design model of structural parameters for shield cutterhead is formulated,based on the complex engineering technical requirements. In the model, as the objective function of the model is a composite function of the strength and stiffness, the response surface method is applied to formulate the approximate function of objective function in order to reduce the solution scale of optimal problem. A multi-objective genetic algorithm is used to solve the cutterhead structure design problem and the change rule of the stress-strain with various structural parameters as well as their optimal values were researched under specific geological conditions. The results show that compared with original cutterhead structure scheme, the obtained optimal scheme of the cutterhead structure can greatly improve the strength and stiffness of the cutterhead, which can be seen from the reduction of its maximum equivalent stress by 21.2%, that of its maximum deformation by 0.75%, and that of its mass by 1.04%. 展开更多
关键词 shield tunneling machine cutterhead structural parameters fuzzy mathematics finite element optimization
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Generating Fuzzy Rule-based Systems from Examples Based on Robust Support Vector Machine
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作者 贾泂 张浩然 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期144-147,共4页
This paper firstly proposes a new support vector machine regression (SVR) with a robust loss function, and designs a gradient based algorithm for implementation of the SVR, then uses the SVR to extract fuzzy rules and... This paper firstly proposes a new support vector machine regression (SVR) with a robust loss function, and designs a gradient based algorithm for implementation of the SVR, then uses the SVR to extract fuzzy rules and designs fuzzy rule-based system. Simulations show that fuzzy rule-based system technique based on robust SVR achieves superior performance to the conventional fuzzy inference method, the proposed method provides satisfactory performance with excellent approximation and generalization property than the existing algorithm. 展开更多
关键词 support vector machine fuzzy rules rule-based system generalization.
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Deduction Theorem and Hypothetical Syllogism Rule on Fuzzy Logic System
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作者 YANGXiao-bin DENGShu-xian 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第2期206-213,共8页
Cancelled the first axiom L1) or the third axiom L3) of the classical formal logic system we established two kinds of quasi-formal deductive system, LG-R^* and LG^* respectively. In LG-R^* we proved that neither the d... Cancelled the first axiom L1) or the third axiom L3) of the classical formal logic system we established two kinds of quasi-formal deductive system, LG-R^* and LG^* respectively. In LG-R^* we proved that neither the deduction theorem nor the hypothetical syllogism (HS) rule held but a deduction theorem and an HS rule are obtained in a weak sense. We also proved that both the deduction theorem and the hypothetical syllogism(HS) rule hold in LG^*. 展开更多
关键词 fuzzy logic system deduction theorem hypothetical syllogism(HS) rule weak HS rule
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Agents and Lattice-valued Logic
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作者 Germanno Resconi 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期113-116,共4页
In fuzzy set theory, instead of the underlying membership set being a two-valued set it is a multi-valued set that generally has the structure of a lattice L with a minimal element O and the maximal element I. Further... In fuzzy set theory, instead of the underlying membership set being a two-valued set it is a multi-valued set that generally has the structure of a lattice L with a minimal element O and the maximal element I. Furthermore if ∧, ∨, → and ┐ are defined in the set L, then we can use these operations to define, as in the ordinary set theory, operations on fuzzy subsets. In this paper we give a model of the Lattice-Valued Logic with set of agents. Any agents know the logic value of a sentence p. The logic value is compatible with all of the accessible conceptual models or worlds of p inside the agent. Agent can be rational or irrational in the use of the logic operation. Every agent of n agents can have the same set of conceptual models for p and know the same logic for p in this case the agents form a consistent group of agents. When agents have different conceptual models for p, different subgroup of agents know different logic value for p. In this case the n agents are inconsistent in the expression of the logic value for p. The valuation structure of set of agents can be used as a semantic model for the Lattice-valued Logic and fuzzy logic. 展开更多
关键词 AGENT Lattice-valued Log fuzzy.
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Memory Chain in a Chaotic Autoassociative Neural Network
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作者 范宏 王直杰 张珏 《Journal of Donghua University(English Edition)》 EI CAS 2005年第1期113-115,共3页
Memory chain is observed in a chaotic autoassociative neural network. The network recalls first stored pattern from a fragment of a memory, stays at this pattern for a while, transits to the second stored pattern that... Memory chain is observed in a chaotic autoassociative neural network. The network recalls first stored pattern from a fragment of a memory, stays at this pattern for a while, transits to the second stored pattern that overlaps with the first recalled pattern.Then it stays at the second recalled pattern for a while, transits to the third stored pattern that overlaps with the second recalled pattern, and so on. Thus a memory chain is generated. The memory chain ends with the pattern that overlaps no other stored patten. This phenomenon is similar to the way of recalling process of human beings in some respects. 展开更多
关键词 CHAOS neural network associative memory.
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Simultaneous Perturbation Stochastic Approximation Algorithm Combined with Neural Network and Fuzzy Simulation
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作者 宁玉富 唐万生 郭长友 《Transactions of Tianjin University》 EI CAS 2008年第1期43-49,共7页
In order to solve three kinds of fuzzy programm model, fuzzy chance-constrained programming mode ng models, i.e. fuzzy expected value and fuzzy dependent-chance programming model, a simultaneous perturbation stochast... In order to solve three kinds of fuzzy programm model, fuzzy chance-constrained programming mode ng models, i.e. fuzzy expected value and fuzzy dependent-chance programming model, a simultaneous perturbation stochastic approximation algorithm is proposed by integrating neural network with fuzzy simulation. At first, fuzzy simulation is used to generate a set of input-output data. Then a neural network is trained according to the set. Finally, the trained neural network is embedded in simultaneous perturbation stochastic approximation algorithm. Simultaneous perturbation stochastic approximation algorithm is used to search the optimal solution. Two numerical examples are presented to illustrate the effectiveness of the proposed algorithm. 展开更多
关键词 fuzzy variable fuzzy programming fuzzy simulation neural network approximation theory perturbation techniques computer simulation simultaneous perturbation stochasticapproximation algorithm
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Supply Chain Production-distribution Cost Optimization under Grey Fuzzy Uncertainty
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作者 刘东波 陈玉娟 +1 位作者 黄道 添玉 《Journal of Donghua University(English Edition)》 EI CAS 2008年第1期41-47,共7页
Most supply chain programming problems are restricted to the deterministic situations or stochastic environmcnts. Considering twofold uncertainty combining grey and fuzzy factors, this paper proposes a hybrid uncertai... Most supply chain programming problems are restricted to the deterministic situations or stochastic environmcnts. Considering twofold uncertainty combining grey and fuzzy factors, this paper proposes a hybrid uncertain programming model to optimize the supply chain production-distribution cost. The programming parameters of the material suppliers, manufacturer, distribution centers, and the customers are integrated into the presented model. On the basis of the chance measure and the credibility of grey fuzzy variable, the grey fuzzy simulation methodology was proposed to generate input-output data for the uncertain functions. The designed neural network can expedite the simulation process after trained from the generated input-output data. The improved Particle Swarm Optimization (PSO) algorithm based on the Differential Evolution (DE) algorithm can optimize the uncertain programming problems. A numerical example was presented to highlight the significance of the uncertain model and the feasibility of the solution strategy. 展开更多
关键词 supply chain optimization grey fuzzy uncertainty neural netwok particle swarm optimization algorithm differential evolution algorithm
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基于灰色模糊评价法的污水厂建设分析
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作者 丁德高 《明日风尚》 2017年第10期326-327,共2页
随着城市化和工业化进程的加快,城市污水产生量不断增大,使得水环境污染日益严重。城市污水处理的严重滞后,已经影响我国区域水污染防治目标的实现,并且严重制约了城市社会经济的可持续发展。因此建设城市污水处理设施成为推动现代化城... 随着城市化和工业化进程的加快,城市污水产生量不断增大,使得水环境污染日益严重。城市污水处理的严重滞后,已经影响我国区域水污染防治目标的实现,并且严重制约了城市社会经济的可持续发展。因此建设城市污水处理设施成为推动现代化城市发展的一项重要工作,这促使我们深入地研究分析污水厂项目建设的影响因素,进一步提升建设项目的管理水平。本文以A、B、C三个污水厂为例,通过优化无量纲化后的灰色理论模糊综合评价法对污水厂建设项目进行深入细致的分析与评价,得到污水厂建设项目的主要影响因素。希望通过重点管理控制这主要影响因素,从而提高污水厂项目的建设水平以及效率。 展开更多
关键词 污水厂建设 灰色理论模糊综合评价 无量纲化
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