The paper analyzes the factors influencing machine tool selection. By using fuzzy mathematics theory, we establish a theorietical model for optimal machine tool selection considering geometric features, clamping size,...The paper analyzes the factors influencing machine tool selection. By using fuzzy mathematics theory, we establish a theorietical model for optimal machine tool selection considering geometric features, clamping size, machining range, machining precision and surface roughness. By means of fuzzy comprehensive evaluation method, the membership degree of machine tool selection and the largest comprehensive evaluation index are determined. Then the reasonably automatic selection of machine tool is realized in the generative computer aided process planning (CAPP) system. Finally, the finite element model based on ABAQUS is established and the cutting process of machine tool is simulated. According to the theoretical and empirical cutting parameters and the curve of surface residual stress, the optimal cutting parameters can be determined.展开更多
A slope stability evaluation method is proposed combining group decision theory,the analytic hierarchy process and fuzzy comprehensive evaluation.The index weight assignment of each evaluation element is determined by...A slope stability evaluation method is proposed combining group decision theory,the analytic hierarchy process and fuzzy comprehensive evaluation.The index weight assignment of each evaluation element is determined by group decision theory and the analytic hierarchy process,and the membership degree of each indicator is determined based on fuzzy set theory.According to the weights and memberships,the membership degrees of the criterion layer are obtained by fuzzy operations to evaluate the slope stability.The results show that(1)the evaluation method comprehensively combines the effects of multiple factors on the slope stability,and the evaluation results are accurate;(2)the evaluation method can fully leverage the experience of the expert group and effectively avoid evaluation errors caused by the subjective bias of a single expert;(3)based on a group decision theory entropy model,this evaluation method can quantitatively evaluate the reliability of expert decisions and effectively improve the efficiency of expert group discussion;and(4)the evaluation method can transform the originally fuzzy and subjective slope stability evaluation into a quantitative evaluation.展开更多
Automatic fixture design is a key link in computer aided process planning. The uncertainty in the selection of fixture design schemes necessitates the use of the fuzzy comprehensive judgment method to automatically se...Automatic fixture design is a key link in computer aided process planning. The uncertainty in the selection of fixture design schemes necessitates the use of the fuzzy comprehensive judgment method to automatically select an optimal fixture design. This paper reports on the development of a computer aided fixture design system for non rotational parts using the fuzzy comprehensive judgment method running in an integrated process planning environment. Several typical non rotational parts with complicated configurations are used to demonstrate the automatic fixture design system.展开更多
基金Shanxi Province Science and Technology Research Project(No.20140321008-03)
文摘The paper analyzes the factors influencing machine tool selection. By using fuzzy mathematics theory, we establish a theorietical model for optimal machine tool selection considering geometric features, clamping size, machining range, machining precision and surface roughness. By means of fuzzy comprehensive evaluation method, the membership degree of machine tool selection and the largest comprehensive evaluation index are determined. Then the reasonably automatic selection of machine tool is realized in the generative computer aided process planning (CAPP) system. Finally, the finite element model based on ABAQUS is established and the cutting process of machine tool is simulated. According to the theoretical and empirical cutting parameters and the curve of surface residual stress, the optimal cutting parameters can be determined.
基金the National Key Research and Development Program of China(No.2017YFC1501302)the National Natural Science Foundation of China(No.41630643)the Fundamental Research Funds for the Central Universities(No.CUGCJ1701)。
文摘A slope stability evaluation method is proposed combining group decision theory,the analytic hierarchy process and fuzzy comprehensive evaluation.The index weight assignment of each evaluation element is determined by group decision theory and the analytic hierarchy process,and the membership degree of each indicator is determined based on fuzzy set theory.According to the weights and memberships,the membership degrees of the criterion layer are obtained by fuzzy operations to evaluate the slope stability.The results show that(1)the evaluation method comprehensively combines the effects of multiple factors on the slope stability,and the evaluation results are accurate;(2)the evaluation method can fully leverage the experience of the expert group and effectively avoid evaluation errors caused by the subjective bias of a single expert;(3)based on a group decision theory entropy model,this evaluation method can quantitatively evaluate the reliability of expert decisions and effectively improve the efficiency of expert group discussion;and(4)the evaluation method can transform the originally fuzzy and subjective slope stability evaluation into a quantitative evaluation.
文摘Automatic fixture design is a key link in computer aided process planning. The uncertainty in the selection of fixture design schemes necessitates the use of the fuzzy comprehensive judgment method to automatically select an optimal fixture design. This paper reports on the development of a computer aided fixture design system for non rotational parts using the fuzzy comprehensive judgment method running in an integrated process planning environment. Several typical non rotational parts with complicated configurations are used to demonstrate the automatic fixture design system.