In operation,risk arising from power transformer faults is of much uncertainty and complicacy.To timely and objectively control the risks,a transformer risk assessment method based on fuzzy analytic hierarchy process(...In operation,risk arising from power transformer faults is of much uncertainty and complicacy.To timely and objectively control the risks,a transformer risk assessment method based on fuzzy analytic hierarchy process(FAHP) and artificial neural network(ANN) from the perspective of accuracy and quickness is proposed.An analytic hierarchy process model for the transformer risk assessment is built by analysis of the risk factors affecting the transformer risk level and the weight relation of each risk factor in transformer risk calculation is analyzed by application of fuzzy consistency judgment matrix;with utilization of adaptive ability and nonlinear mapping ability of the ANN,the risk factors with large weights are used as input of neutral network,and thus intelligent quantitative assessment of transformer risk is realized.The simulation result shows that the proposed method increases the speed and accuracy of the risk assessment and can provide feasible decision basis for the transformer risk management and maintenance decisions.展开更多
针对风力发电机组频发的火灾事故,首先从人-机-环-管角度出发,通过统计分析近20年来全球81起风力发电机组火灾事故案例,得到了21项风力发电机组火灾事故的影响因素;然后通过事故树分析(fault tree analysis,FTA)法演绎推理得到了风力发...针对风力发电机组频发的火灾事故,首先从人-机-环-管角度出发,通过统计分析近20年来全球81起风力发电机组火灾事故案例,得到了21项风力发电机组火灾事故的影响因素;然后通过事故树分析(fault tree analysis,FTA)法演绎推理得到了风力发电机组火灾事故各基本事件的逻辑关系,并根据结构重要度进行了火灾事故致因的定性分析;接着采用模糊层次分析(fuzzy analytic hierarchy process,FAHP)法,将事故树的基本事件从人、机、环、管4个方面整合,构建出风力发电机组火灾事故致因评价指标体系,并以结构重要度系数的顺序为模糊判断矩阵的赋值依据,进行了火灾事故致因的定量分析;最后,根据综合分析结果提出了风力发电机组火灾事故的对策措施。结果表明:机和环境的不安全因素是引发火灾事故的主要致因;电气设备故障和雷击是最主要因素。该研究成果可为风力发电机组的火灾防治提供理论参考。展开更多
In the conceptual design stage of complex products, CBR(Case-Based Reasoning) tool is useful to offer a feasible set of schemes. Then the most adaptive scheme can be generated through a procedure of comparison and e...In the conceptual design stage of complex products, CBR(Case-Based Reasoning) tool is useful to offer a feasible set of schemes. Then the most adaptive scheme can be generated through a procedure of comparison and evaluation. The procedure is essentially a multiple criteria decision-making problem. The traditional multiple criteria programming is not flexible enough in executing the system evaluation algorithm due to both the limited experimental data and the lack of human experiences. To make the CBR tool to be more efficient, a new method for the best choice among the feasible schemes based on the Fuzzy AHP using Fuzzy numbers (FFAHP) is proposed. Since the final results become a problem of ranking the mean of fuzzy numbers by the optimism of decision-maker using the FFAHP, its execution is much more intuitive and effective than with the traditional method.展开更多
为保证汽车行车安全,前舱盖需满足刚度、模态和行人保护等要求。针对汽车前舱盖的轻量化设计需求,建立了铸铝一体化前舱盖有限元模型,分析了前舱盖的刚度、模态和行人保护性能,构建了RBF-Kriging混合近似模型并联合存档微遗传算法(archi...为保证汽车行车安全,前舱盖需满足刚度、模态和行人保护等要求。针对汽车前舱盖的轻量化设计需求,建立了铸铝一体化前舱盖有限元模型,分析了前舱盖的刚度、模态和行人保护性能,构建了RBF-Kriging混合近似模型并联合存档微遗传算法(archive based micro genetic algorithm,AMGA)对前舱盖进行多目标优化。针对多目标优化产生的Pareto解集,提出一种基于模糊层次分析-逼近理想解排序(fuzzy analytic hierarchy process-technique for order preference by similarity to ideal solution,FAHP-TOPSIS)法对Pareto非劣解进行综合性能排名,主客观相结合地选择出最优方案。结果表明,在满足性能要求的前提下,最优一体化前舱盖质量降低了32.14%,轻量化效果显著。展开更多
基金Project(50977003) supported by the National Natural Science Foundation of China
文摘In operation,risk arising from power transformer faults is of much uncertainty and complicacy.To timely and objectively control the risks,a transformer risk assessment method based on fuzzy analytic hierarchy process(FAHP) and artificial neural network(ANN) from the perspective of accuracy and quickness is proposed.An analytic hierarchy process model for the transformer risk assessment is built by analysis of the risk factors affecting the transformer risk level and the weight relation of each risk factor in transformer risk calculation is analyzed by application of fuzzy consistency judgment matrix;with utilization of adaptive ability and nonlinear mapping ability of the ANN,the risk factors with large weights are used as input of neutral network,and thus intelligent quantitative assessment of transformer risk is realized.The simulation result shows that the proposed method increases the speed and accuracy of the risk assessment and can provide feasible decision basis for the transformer risk management and maintenance decisions.
基金This project was partly supported bythe Key Programof the National Natural Science Foundation of China (79990580) .
文摘In the conceptual design stage of complex products, CBR(Case-Based Reasoning) tool is useful to offer a feasible set of schemes. Then the most adaptive scheme can be generated through a procedure of comparison and evaluation. The procedure is essentially a multiple criteria decision-making problem. The traditional multiple criteria programming is not flexible enough in executing the system evaluation algorithm due to both the limited experimental data and the lack of human experiences. To make the CBR tool to be more efficient, a new method for the best choice among the feasible schemes based on the Fuzzy AHP using Fuzzy numbers (FFAHP) is proposed. Since the final results become a problem of ranking the mean of fuzzy numbers by the optimism of decision-maker using the FFAHP, its execution is much more intuitive and effective than with the traditional method.
文摘为保证汽车行车安全,前舱盖需满足刚度、模态和行人保护等要求。针对汽车前舱盖的轻量化设计需求,建立了铸铝一体化前舱盖有限元模型,分析了前舱盖的刚度、模态和行人保护性能,构建了RBF-Kriging混合近似模型并联合存档微遗传算法(archive based micro genetic algorithm,AMGA)对前舱盖进行多目标优化。针对多目标优化产生的Pareto解集,提出一种基于模糊层次分析-逼近理想解排序(fuzzy analytic hierarchy process-technique for order preference by similarity to ideal solution,FAHP-TOPSIS)法对Pareto非劣解进行综合性能排名,主客观相结合地选择出最优方案。结果表明,在满足性能要求的前提下,最优一体化前舱盖质量降低了32.14%,轻量化效果显著。