Machining-features of the workplace are described by using of the object-oriented （O-O） technology. Geometrical machining-features are recognized in the given cut region by using the maximum membership priciple abou...Machining-features of the workplace are described by using of the object-oriented （O-O） technology. Geometrical machining-features are recognized in the given cut region by using the maximum membership priciple about the fuzzy set. Depending on the IF-THEN rule and the fuzzy matching method, the rough information of the machining-process for high-speed milling （HSM） is extracted based on the database of machining-process for HSM. The optimization model of machining-process scheme is established to obtain shorter cut time, lower cost or higher surface quality. It is helpful to form successful cases for HSM. NC programming for HSM is realized according to optimized machining-process data from HSM cases selected by the optimization model and the extracted information of machining-process.展开更多
For thin-walled parts,uniform allowance to each machining surface is allocated by the traditional machining method.Considering the sequence of the adjacent machining features,it may cause poor stiffness for some side ...For thin-walled parts,uniform allowance to each machining surface is allocated by the traditional machining method.Considering the sequence of the adjacent machining features,it may cause poor stiffness for some side walls due to a minor wall thickness,which may cause the deformation of the final formed parts to be large,or deduce machining efficiency for some machining features due to too thick remains.In order to address this issue,a non-uniform allowance allocation method based on interim state stiffness of machining features for the finishing of thin-walled structural parts is proposed in this paper.In this method,the interim state model of machining features is constructed according to the machining sequence of the parts,and the stiffness of the side wall is taken as the evaluation index to allocate reasonable allowance value to the corresponding machining surface to ensure the stiffness requirement of the parts in the machining process.According to the finite element simulation results,the non-uniform allowance allocation method proposed in this paper can effectively improve the stiffness of the parts and reduce the deformation of the parts,when compared with the traditional uniform allowance machining method.展开更多
The NC programming for complex components has lots drawbacks such as excessive repetitious labors,heavy work- load and lack of optimixation,which are especially serious in NC programming for complex components of mari...The NC programming for complex components has lots drawbacks such as excessive repetitious labors,heavy work- load and lack of optimixation,which are especially serious in NC programming for complex components of marine diesel.Based on the key technologies of applying KBE(Knowledge Based Engineering)to NC programming——knowledge representation,general- ized knowledge base,knowledge acquisition and knowledge reasoning,the system of intelligent NC programming for complex com- ponents of marine diesel has been built by means of the knowledge template and the UG/Open.The experiment results indicate that the NC program generated with high efficiency of NC programming by the system is accurate enough to meet the need of NC ma- chining.Consequently,the automatization and intelligentization of NC programming has been presented,and the study is proved to be a successful attempt in the area of applying KBE to NC programming.展开更多
Quadratic 0-1 problems with linear inequality constraints are briefly considered in this paper.Global optimality conditions for these problems,including a necessary condition and some sufficient conditions,are present...Quadratic 0-1 problems with linear inequality constraints are briefly considered in this paper.Global optimality conditions for these problems,including a necessary condition and some sufficient conditions,are presented.The necessary condition is expressed without dual variables.The relations between the global optimal solutions of nonconvex quadratic 0-1 problems and the associated relaxed convex problems are also studied.展开更多
In this paper,quadratic 0-1 programming problem (I) is considered, in terms of its features quadratic 0-1 programming problem is solved by linear approxity heurstic algrothm and a developed tabu search ahgrothm .
Concave resource allocation problem is an integer programming problem of minimizing a nonincreasing concave function subject to a convex nondecreasing constraint and bounded integer variables. This class of problems a...Concave resource allocation problem is an integer programming problem of minimizing a nonincreasing concave function subject to a convex nondecreasing constraint and bounded integer variables. This class of problems are encountered in optimization models involving economies of scale. In this paper, a new hybrid dynamic programming method was proposed for solving concave resource allocation problems. A convex underestimating function was used to approximate the objective function and the resulting convex subproblem was solved with dynamic programming technique after transforming it into a 0-1 linear knapsack problem. To ensure the convergence, monotonicity and domain cut technique was employed to remove certain integer boxes and partition the revised domain into a union of integer boxes. Computational results were given to show the efficiency of the algorithm.展开更多
The purpose of this research is to implement an IT-based education program in order to promote cervical cancer screenings for women aged 20 - 29 years, as well as to examine the results of said program. This is a long...The purpose of this research is to implement an IT-based education program in order to promote cervical cancer screenings for women aged 20 - 29 years, as well as to examine the results of said program. This is a longitudinal/comparative study of two groups, one for which the program was implemented (the intervention group), and the other for which it was not (the control group). The program consisted of attending a health lecture and encouragement to be screened one month, six months, and one year later sent through IT-based methods. The target was unmarried women aged 20 - 29 who had neither previously given birth nor had been screened for cervical cancer in a period one year prior. They were divided into two groups, the intervention group (n = 142) and control group (n = 145). The effectiveness of the program was assessed via an initial survey and further surveys six months and one year later. Results were based on the Japanese version of the Health Belief Model Scale for Cervical Cancer and the Pap Smear Test (HBMSCCPST), knowledge scores in the categories of Healthy Lifestyles, Cervical Cancer, Cervical Cancer Screening, and screening behavior. A two-way ANOVA of the HBMSCCPST subscales and knowledge scores in the initial, six-month, and one-year surveys was performed, showing interaction in Cervical Cancer (p = 0.00). Main effects were observed in Cervical Cancer Screening (p = 0.00) and Healthy Lifestyles (p = 0.00). Regarding the amount of change from the initial survey, knowledge scores in the Cervical Cancer (p = 0.027) and Cervical Cancer Screening (p = 0.016) categories were significantly higher in the intervention group than in the control group. There was no significant difference in cervical cancer screening rates (p = 0.26) between the two groups. However, a small-degree effect size was observed for Benefits, Seriousness, and Susceptibility subscales in both examinees and non-examinees. Although the educational program of this study was effective in improving the knowledge of women in their twenties, there was little improvement in HBMSCCPST and it did not lead to the promotion of cervical cancer screening. In order to raise interest in cervical cancer screening, it is necessary to consider useful content to guide women to consult with healthcare professionals, a long-term population approach, and organizational structure of consultation.展开更多
In this paper, we consider the socalled k-coloring problem in general case.Firstly, a special quadratic 0-1 programming is constructed to formulate k-coloring problem. Secondly, by use of the equivalence between above...In this paper, we consider the socalled k-coloring problem in general case.Firstly, a special quadratic 0-1 programming is constructed to formulate k-coloring problem. Secondly, by use of the equivalence between above quadratic0-1 programming and its relaxed problem, k-coloring problem is converted intoa class of (continuous) nonconvex quadratic programs, and several theoreticresults are also introduced. Thirdly, linear programming approximate algorithmis quoted and verified for this class of nonconvex quadratic programs. Finally,examining problems which are used to test the algorithm are constructed andsufficient computation experiments are reported.展开更多
To relax convexity assumptions imposed on the functions in theorems on sufficient conditions and duality,new concepts of generalized dI-G-type Ⅰ invexity were introduced for nondifferentiable multiobjective programmi...To relax convexity assumptions imposed on the functions in theorems on sufficient conditions and duality,new concepts of generalized dI-G-type Ⅰ invexity were introduced for nondifferentiable multiobjective programming problems.Based upon these generalized invexity,G-Fritz-John （G-F-J） and G-Karnsh-Kuhn-Tucker （G-K-K-T） types sufficient optimality conditions were established for a feasible solution to be an efficient solution.Moreover,weak and strict duality results were derived for a G-Mond-Weir type dual under various types of generalized dI-G-type Ⅰ invexity assumptions.展开更多
提出了一种基于STEP-NC的数控车削加工仿真系统,该仿真系统能够验证STEP-NC数控程序、模拟实际系统运行。讨论了仿真系统的译码器、基于特征的加工数据库、实体建模以及仿真驱动等组成模块实现的关键技术和方法。介绍了仿真系统的建模工...提出了一种基于STEP-NC的数控车削加工仿真系统,该仿真系统能够验证STEP-NC数控程序、模拟实际系统运行。讨论了仿真系统的译码器、基于特征的加工数据库、实体建模以及仿真驱动等组成模块实现的关键技术和方法。介绍了仿真系统的建模工具V isua l C++和O penGL。最后指出了本文研究对于STEP-NC数控加工研究的意义。展开更多
Simplified Hough Transform (HT) and Adaptive Including Box (AIB) approach are proposed. The size of AIB is controlled according to the precision requirement of machining. The image data of part contour is turned into ...Simplified Hough Transform (HT) and Adaptive Including Box (AIB) approach are proposed. The size of AIB is controlled according to the precision requirement of machining. The image data of part contour is turned into a set of line segments and then NC program for machining the contour is generated .展开更多
文摘Machining-features of the workplace are described by using of the object-oriented （O-O） technology. Geometrical machining-features are recognized in the given cut region by using the maximum membership priciple about the fuzzy set. Depending on the IF-THEN rule and the fuzzy matching method, the rough information of the machining-process for high-speed milling （HSM） is extracted based on the database of machining-process for HSM. The optimization model of machining-process scheme is established to obtain shorter cut time, lower cost or higher surface quality. It is helpful to form successful cases for HSM. NC programming for HSM is realized according to optimized machining-process data from HSM cases selected by the optimization model and the extracted information of machining-process.
基金supported by the National Science and Technology Major Project of the Ministry of Science and Technology of China(No.2015ZX04001002).
文摘For thin-walled parts,uniform allowance to each machining surface is allocated by the traditional machining method.Considering the sequence of the adjacent machining features,it may cause poor stiffness for some side walls due to a minor wall thickness,which may cause the deformation of the final formed parts to be large,or deduce machining efficiency for some machining features due to too thick remains.In order to address this issue,a non-uniform allowance allocation method based on interim state stiffness of machining features for the finishing of thin-walled structural parts is proposed in this paper.In this method,the interim state model of machining features is constructed according to the machining sequence of the parts,and the stiffness of the side wall is taken as the evaluation index to allocate reasonable allowance value to the corresponding machining surface to ensure the stiffness requirement of the parts in the machining process.According to the finite element simulation results,the non-uniform allowance allocation method proposed in this paper can effectively improve the stiffness of the parts and reduce the deformation of the parts,when compared with the traditional uniform allowance machining method.
基金Funded by University natural science fund of Jiangsu(Grant No.2005JD016J),Open fund of shipping advanced manufacturing key laboratory of Jiangsu province.
文摘The NC programming for complex components has lots drawbacks such as excessive repetitious labors,heavy work- load and lack of optimixation,which are especially serious in NC programming for complex components of marine diesel.Based on the key technologies of applying KBE(Knowledge Based Engineering)to NC programming——knowledge representation,general- ized knowledge base,knowledge acquisition and knowledge reasoning,the system of intelligent NC programming for complex com- ponents of marine diesel has been built by means of the knowledge template and the UG/Open.The experiment results indicate that the NC program generated with high efficiency of NC programming by the system is accurate enough to meet the need of NC ma- chining.Consequently,the automatization and intelligentization of NC programming has been presented,and the study is proved to be a successful attempt in the area of applying KBE to NC programming.
文摘Quadratic 0-1 problems with linear inequality constraints are briefly considered in this paper.Global optimality conditions for these problems,including a necessary condition and some sufficient conditions,are presented.The necessary condition is expressed without dual variables.The relations between the global optimal solutions of nonconvex quadratic 0-1 problems and the associated relaxed convex problems are also studied.
文摘In this paper,quadratic 0-1 programming problem (I) is considered, in terms of its features quadratic 0-1 programming problem is solved by linear approxity heurstic algrothm and a developed tabu search ahgrothm .
基金Project supported by the National Natural Science Foundation oChina (Grant os.79970107 and 10271073)
文摘Concave resource allocation problem is an integer programming problem of minimizing a nonincreasing concave function subject to a convex nondecreasing constraint and bounded integer variables. This class of problems are encountered in optimization models involving economies of scale. In this paper, a new hybrid dynamic programming method was proposed for solving concave resource allocation problems. A convex underestimating function was used to approximate the objective function and the resulting convex subproblem was solved with dynamic programming technique after transforming it into a 0-1 linear knapsack problem. To ensure the convergence, monotonicity and domain cut technique was employed to remove certain integer boxes and partition the revised domain into a union of integer boxes. Computational results were given to show the efficiency of the algorithm.
文摘The purpose of this research is to implement an IT-based education program in order to promote cervical cancer screenings for women aged 20 - 29 years, as well as to examine the results of said program. This is a longitudinal/comparative study of two groups, one for which the program was implemented (the intervention group), and the other for which it was not (the control group). The program consisted of attending a health lecture and encouragement to be screened one month, six months, and one year later sent through IT-based methods. The target was unmarried women aged 20 - 29 who had neither previously given birth nor had been screened for cervical cancer in a period one year prior. They were divided into two groups, the intervention group (n = 142) and control group (n = 145). The effectiveness of the program was assessed via an initial survey and further surveys six months and one year later. Results were based on the Japanese version of the Health Belief Model Scale for Cervical Cancer and the Pap Smear Test (HBMSCCPST), knowledge scores in the categories of Healthy Lifestyles, Cervical Cancer, Cervical Cancer Screening, and screening behavior. A two-way ANOVA of the HBMSCCPST subscales and knowledge scores in the initial, six-month, and one-year surveys was performed, showing interaction in Cervical Cancer (p = 0.00). Main effects were observed in Cervical Cancer Screening (p = 0.00) and Healthy Lifestyles (p = 0.00). Regarding the amount of change from the initial survey, knowledge scores in the Cervical Cancer (p = 0.027) and Cervical Cancer Screening (p = 0.016) categories were significantly higher in the intervention group than in the control group. There was no significant difference in cervical cancer screening rates (p = 0.26) between the two groups. However, a small-degree effect size was observed for Benefits, Seriousness, and Susceptibility subscales in both examinees and non-examinees. Although the educational program of this study was effective in improving the knowledge of women in their twenties, there was little improvement in HBMSCCPST and it did not lead to the promotion of cervical cancer screening. In order to raise interest in cervical cancer screening, it is necessary to consider useful content to guide women to consult with healthcare professionals, a long-term population approach, and organizational structure of consultation.
文摘In this paper, we consider the socalled k-coloring problem in general case.Firstly, a special quadratic 0-1 programming is constructed to formulate k-coloring problem. Secondly, by use of the equivalence between above quadratic0-1 programming and its relaxed problem, k-coloring problem is converted intoa class of (continuous) nonconvex quadratic programs, and several theoreticresults are also introduced. Thirdly, linear programming approximate algorithmis quoted and verified for this class of nonconvex quadratic programs. Finally,examining problems which are used to test the algorithm are constructed andsufficient computation experiments are reported.
基金National Natural Science Foundation of China(No.11071110)
文摘To relax convexity assumptions imposed on the functions in theorems on sufficient conditions and duality,new concepts of generalized dI-G-type Ⅰ invexity were introduced for nondifferentiable multiobjective programming problems.Based upon these generalized invexity,G-Fritz-John （G-F-J） and G-Karnsh-Kuhn-Tucker （G-K-K-T） types sufficient optimality conditions were established for a feasible solution to be an efficient solution.Moreover,weak and strict duality results were derived for a G-Mond-Weir type dual under various types of generalized dI-G-type Ⅰ invexity assumptions.
文摘提出了一种基于STEP-NC的数控车削加工仿真系统,该仿真系统能够验证STEP-NC数控程序、模拟实际系统运行。讨论了仿真系统的译码器、基于特征的加工数据库、实体建模以及仿真驱动等组成模块实现的关键技术和方法。介绍了仿真系统的建模工具V isua l C++和O penGL。最后指出了本文研究对于STEP-NC数控加工研究的意义。
基金This project is supported by the Science & Technology Development Foundation of Ministry of Machinery Industry
文摘Simplified Hough Transform (HT) and Adaptive Including Box (AIB) approach are proposed. The size of AIB is controlled according to the precision requirement of machining. The image data of part contour is turned into a set of line segments and then NC program for machining the contour is generated .
