Because of the powerful mapping ability, back propagation neural network (BP-NN) has been employed in computer-aided product design (CAPD) to establish the property prediction model. The backward problem in CAPD is to...Because of the powerful mapping ability, back propagation neural network (BP-NN) has been employed in computer-aided product design (CAPD) to establish the property prediction model. The backward problem in CAPD is to search for the appropriate structure or composition of the product with desired property, which is an optimization problem. In this paper, a global optimization method of using the a BB algorithm to solve the backward problem is presented. In particular, a convex lower bounding function is constructed for the objective function formulated with BP-NN model, and the calculation of the key parameter a is implemented by recurring to the interval Hessian matrix of the objective function. Two case studies involving the design of dopamine β-hydroxylase (DβH) inhibitors and linear low density polyethylene (LLDPE) nano composites are investigated using the proposed method.展开更多
The ongoing need for better fuel economy and lower exhaust pollution of vehicles has increased the employment of electric power steering(EPS)in automotives.Optimal design of EPS for a product family reduces the develo...The ongoing need for better fuel economy and lower exhaust pollution of vehicles has increased the employment of electric power steering(EPS)in automotives.Optimal design of EPS for a product family reduces the development and fabrication costs significantly.In this paper,the TOPSIS method along with the NSGA-Ⅱis employed to find an optimum family of EPS for an automotive platform.A multi-objective optimization problem is defined considering road feel,steering portability,RMS of Ackerman error,and product family penalty function(PFPF)as the conflicting objective functions.The results for the single objective optimization problems and the ones for the multi-objective optimization problem,as well as two suggested trade-off design points are presented,compared and discussed.For the two suggested points,performance at one objective function is deteriorated by about 1%,while the commonality is increased by 20%–40%,which shows the effectiveness of the proposed method in first finding the non-dominated design points and then selecting the trade-off among the obtained points.The results indicate that the obtained trade-off points have superior performance within the product family with maximum number of common parts.展开更多
Product design plays a decisive role in material resource consumption in manufacturing systems. So it is significant to study optimal utilization of material resources of manufacturing system from the perspective of p...Product design plays a decisive role in material resource consumption in manufacturing systems. So it is significant to study optimal utilization of material resources of manufacturing system from the perspective of product design. This paper firstly defines concept of product design, then after an analysis of design objectives the author proposes a target system of product design with three subsystems: structural system, functional system, and technical system. Finally, a product design system on Architectural Metal Structure Enterprises is developed and used in light of the great consumption of material resources in Metal Structure Enterprises. The system has got an obvious effect on improving comprehensive optimal using rate of material resources of enterprises, reducing design cycle, improving management of enterprises.展开更多
Virtual dynamic optimization design can avoid the repeated process from de-sign to trial-manufacture and test.The designer can analyze and optimize the productstructures in virtual visualization environment.The design...Virtual dynamic optimization design can avoid the repeated process from de-sign to trial-manufacture and test.The designer can analyze and optimize the productstructures in virtual visualization environment.The design cycle is shortened and the costis reduced.The paper analyzed the peculiarity of virtual optimization design,and put for-wards the thought and flow to implement virtual optimization design.The example to opti-mize the internal grinder was studied via establishing precise finite element model,modi-fying the layout of Stiffened Plates and designing parameters of the worktable,and usingthe technology of modal frequency revision and the technology of multiple tuned damper.The result of optimization design compared the new grinder with the original grinder showsthat the entire machine's first orders natural frequency is enhanced by 17%,and the re-sponse displacement of the grinding-head has dropped by 28% under the first order natu-ral frequency and by 41% under second order natural frequency.Finally,the dynamic per-formance of the internal grinder was optimized.展开更多
Product system design is a mature concept in western developed countries. It has been applied in war industry during the last century. However,up until now,functional combination is still the main method for product s...Product system design is a mature concept in western developed countries. It has been applied in war industry during the last century. However,up until now,functional combination is still the main method for product system de-sign in China. Therefore,in terms of a concept of product generation and product interaction we are in a weak position compared with the requirements of global markets. Today,the idea of serial product design has attracted much attention in the design field and the definition of product generation as well as its parameters has already become the standard in serial product designs. Although the design of a large-scale NC machine tool is complicated,it can be further optimized by the precise exercise of object design by placing the concept of platform establishment firmly into serial product de-sign. The essence of a serial product design has been demonstrated by the design process of a large-scale NC machine tool.展开更多
Complicated mechanical products normally consist of multi-parameter mechanisms.The couplings between two tmechanisms are either strong or weak.The traditional optimal design methods cannot meet the requirements of opt...Complicated mechanical products normally consist of multi-parameter mechanisms.The couplings between two tmechanisms are either strong or weak.The traditional optimal design methods cannot meet the requirements of optimal structural design of the complicated multi-parameter mechanical products.On the basis of analyzing the optimal design methods and the data mining principles,an improved iterative dichotomizer 3(ID3) algorithm is hereby put forth to bring out an optimal design information model integrated with the data mining technology as well as an optimal structural design system of complicated mechanical products based on the data mining principles.The system is demonstrated by the optimal structural design of the mainframe of the full face rock tunnel boring machine(TBM).An example shows that the data mining technology has fully tackled the issues of the optimal structural design of complicated mechanical products.展开更多
After reviewing the literature and methodology-related issues within the field of product family design, a deficiency in the current design and development of product family is pointed out. The concept of hierarchical...After reviewing the literature and methodology-related issues within the field of product family design, a deficiency in the current design and development of product family is pointed out. The concept of hierarchical associated design is proposed in this article, according to the deficiency~ and the methods and models for realizing the notion above are described. A two-dimensional analytical model is constructed based on the composing levels and developing processes of product family. The optimization models to hierarchical associated design problems are grouped into two categories： overall-local and key-subordinate. The algorithms of the models are discussed in this paper展开更多
文摘Because of the powerful mapping ability, back propagation neural network (BP-NN) has been employed in computer-aided product design (CAPD) to establish the property prediction model. The backward problem in CAPD is to search for the appropriate structure or composition of the product with desired property, which is an optimization problem. In this paper, a global optimization method of using the a BB algorithm to solve the backward problem is presented. In particular, a convex lower bounding function is constructed for the objective function formulated with BP-NN model, and the calculation of the key parameter a is implemented by recurring to the interval Hessian matrix of the objective function. Two case studies involving the design of dopamine β-hydroxylase (DβH) inhibitors and linear low density polyethylene (LLDPE) nano composites are investigated using the proposed method.
文摘The ongoing need for better fuel economy and lower exhaust pollution of vehicles has increased the employment of electric power steering(EPS)in automotives.Optimal design of EPS for a product family reduces the development and fabrication costs significantly.In this paper,the TOPSIS method along with the NSGA-Ⅱis employed to find an optimum family of EPS for an automotive platform.A multi-objective optimization problem is defined considering road feel,steering portability,RMS of Ackerman error,and product family penalty function(PFPF)as the conflicting objective functions.The results for the single objective optimization problems and the ones for the multi-objective optimization problem,as well as two suggested trade-off design points are presented,compared and discussed.For the two suggested points,performance at one objective function is deteriorated by about 1%,while the commonality is increased by 20%–40%,which shows the effectiveness of the proposed method in first finding the non-dominated design points and then selecting the trade-off among the obtained points.The results indicate that the obtained trade-off points have superior performance within the product family with maximum number of common parts.
基金Foundation item: Funded by China 863 R&D Program(No: 2002AA414080)
文摘Product design plays a decisive role in material resource consumption in manufacturing systems. So it is significant to study optimal utilization of material resources of manufacturing system from the perspective of product design. This paper firstly defines concept of product design, then after an analysis of design objectives the author proposes a target system of product design with three subsystems: structural system, functional system, and technical system. Finally, a product design system on Architectural Metal Structure Enterprises is developed and used in light of the great consumption of material resources in Metal Structure Enterprises. The system has got an obvious effect on improving comprehensive optimal using rate of material resources of enterprises, reducing design cycle, improving management of enterprises.
基金Supported by the National Natural Science Foundation of China(50375026)
文摘Virtual dynamic optimization design can avoid the repeated process from de-sign to trial-manufacture and test.The designer can analyze and optimize the productstructures in virtual visualization environment.The design cycle is shortened and the costis reduced.The paper analyzed the peculiarity of virtual optimization design,and put for-wards the thought and flow to implement virtual optimization design.The example to opti-mize the internal grinder was studied via establishing precise finite element model,modi-fying the layout of Stiffened Plates and designing parameters of the worktable,and usingthe technology of modal frequency revision and the technology of multiple tuned damper.The result of optimization design compared the new grinder with the original grinder showsthat the entire machine's first orders natural frequency is enhanced by 17%,and the re-sponse displacement of the grinding-head has dropped by 28% under the first order natu-ral frequency and by 41% under second order natural frequency.Finally,the dynamic per-formance of the internal grinder was optimized.
文摘Product system design is a mature concept in western developed countries. It has been applied in war industry during the last century. However,up until now,functional combination is still the main method for product system de-sign in China. Therefore,in terms of a concept of product generation and product interaction we are in a weak position compared with the requirements of global markets. Today,the idea of serial product design has attracted much attention in the design field and the definition of product generation as well as its parameters has already become the standard in serial product designs. Although the design of a large-scale NC machine tool is complicated,it can be further optimized by the precise exercise of object design by placing the concept of platform establishment firmly into serial product de-sign. The essence of a serial product design has been demonstrated by the design process of a large-scale NC machine tool.
基金the 10th Five Years National Key Technical Equipment Development Project of China(No. ZZ02-03-03-01)
文摘Complicated mechanical products normally consist of multi-parameter mechanisms.The couplings between two tmechanisms are either strong or weak.The traditional optimal design methods cannot meet the requirements of optimal structural design of the complicated multi-parameter mechanical products.On the basis of analyzing the optimal design methods and the data mining principles,an improved iterative dichotomizer 3(ID3) algorithm is hereby put forth to bring out an optimal design information model integrated with the data mining technology as well as an optimal structural design system of complicated mechanical products based on the data mining principles.The system is demonstrated by the optimal structural design of the mainframe of the full face rock tunnel boring machine(TBM).An example shows that the data mining technology has fully tackled the issues of the optimal structural design of complicated mechanical products.
文摘After reviewing the literature and methodology-related issues within the field of product family design, a deficiency in the current design and development of product family is pointed out. The concept of hierarchical associated design is proposed in this article, according to the deficiency~ and the methods and models for realizing the notion above are described. A two-dimensional analytical model is constructed based on the composing levels and developing processes of product family. The optimization models to hierarchical associated design problems are grouped into two categories： overall-local and key-subordinate. The algorithms of the models are discussed in this paper
