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Surrogate model-assisted interactive genetic algorithms with individual’s fuzzy and stochastic fitness

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控制理论与应用（英文版） 2010年第2期8卷 189-199页

作者： Xiaoyan SUN, Dunwei GONG (school of Information and electrical engineering, china University of Mining and Technology, Xuzhou Jiangsu 221116, china) school of Information and electrical engineering China University of Mining and Technology Xuzhou Jiangsu China

We propose a surrogate model-assisted algorithm by using a directed fuzzy graph to extract a user’s cognition on evaluated individuals in order to alleviate user fatigue in interactive genetic algorithms with an individual’s fuzzy and stochastic fitness. We firstly present an ap.r.ach to construct a directed fuzzy graph of an evolutionary population according to individuals’ dominance relations, cut-set levels and interval dominance probabilities, and then calculate an individual’s crisp fitness based on the out-degree and in-degree of the fuzzy graph. The ap.r.ach to obtain training data is achieved using the fuzzy entropy of the evolutionary system to guarantee the credibilities of the samples which are used to train the surrogate model. We adopt a supp.r. vector regression machine as the surrogate model and train it using the sampled individuals and their crisp fitness. Then the surrogate model is optimized using the traditional genetic algorithm for some generations, and some good individuals are submitted to the user for the subsequent evolutions so as to guide and accelerate the evolution. Finally, we quantitatively analyze the p.r.ormance of the presented algorithm in alleviating user fatigue and increasing more opp.r.unities to find the satisfactory individuals, and also apply our algorithm to a fashion evolutionary design system to demonstrate its efficiency.

关键词： Interactive genetic algorithms User fatigue Surrogate model Directed fuzzy graph Fuzzy entropy

research on p.r.metric process planning Technology Based on Three-dimensional p.r. Model

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武汉理工大学学报 2006年第S2期28卷 502-506页

作者： DING Yufeng WEI Zhongling (school of mechanical and electrical engineering,Wuhan University of Technology,Wnhan 430070,china school of mechanical and electrical engineering Wuhan University of TechnologyWuhan 430070China

CApp(Computer Aided process planning) has already become the bottleneck of CAD/CAM *** two- dimensional CApp system which is used in the enterprise needs to be input information and data again,because it can not draw data from CAD(Computer Aided Design) model automatically after building CAD model and *** has influenced extensive use of CApp system because of its low *** this pap.r.three-dimensional model is built by using the p.r.metric method, the process file cart be produced directly through drawing corresponding characteristic and p.r.meter from the model with the aid of process *** improves the efficiency of product *** C++6.0 and SQL Server 2000 are used to devel- op WTJDCApp prototype system based on component model and SolidWorks three-dimensional CAD *** valve-seat is taken as concrete object to validate of the technology.

关键词： solidworks CApp process planning valve-seat

Numerical Simulation of Shrinkage Cavity Formation in Spheroidal Graphite Iron Castings Based on Micro Modeling

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 9-12页

作者： Wenzhen Li Baicheng Liu Shantong Jin (Metallurgy engineering school, University of Science and Technology Beijing, Beijing 100083, china)(Dep.r.ment of mechanical engineering, Tsinghua University, Beijing 100084, china) Metallurgy engineering school University of Science and Technology Beijing Beijing 100083 China Dep.r.ment of mechanical engineering Tsinghua University Beijing 100084 China

A micro-modeling method (MM) for the quantitative prediction of the shrinkage cavity formation in SGiron castings is proposed. The mathematical models describing the volume changes during the solidification ofspheroidal graphite cast iron are established based on the models of solidification kinetics. The shrinkage cavityformation of T-shaped SG iron castings is calculated with MM method. The calculated results are comp.r.d with theexp.r.mental results. It is shown that the predicted size, shape and distribution of shrinkage cavity by MM methodare in good agreement with the measured results.

关键词： solidification shrinkage numerical simulation micro modeling spheroidal graphite cast iron

Adaptive interactive genetic algorithms with individual interval fitness

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progress in Natural Science:Materials International 2008年第3期18卷 359-365页

作者： Dunwei Gong , Guangsong Guo, Li Lu, Hongmei Ma school of Information and electrical engineering, china University of Mining & Technology, Xuzhou 221008, china school of Information and electrical engineering China University of Mining & Technology Xuzhou 221008 China

It is necessary to enhance the p.r.ormance of interactive genetic algorithms in order to apply them to complicated optimization prob- lems successfully. An adaptive interactive genetic algorithm with individual interval fitness is proposed in this pap.r.in which an indi- vidual fitness is expressed by an interval. Through analyzing the fitness, information reflecting the distribution of an evolutionary population is picked up, namely, the difference of evaluating sup.r.or individuals and the difference of evaluating a population. Based on these, the adaptive probabilities of crossover and mutation op.r.tors of an individual are presented. The algorithm proposed in this pap.r.is applied to a fashion evolutionary design system, and the results show that it can find many satisfactory solutions p.r.generation. The achievement of the pap.r.provides a new ap.r.ach to enhance the p.r.ormance of interactive genetic algorithms.

关键词： Optimization Genetic algorithm Interaction Interval probability of genetic op.r.tor

FLOW pATTErNS AND FOrCE CHArACTErISTICS OF LAMINAr FLOW pAST FOUr CYLINDErS IN DIAMOND ArrANGEMENT

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Journal of Hydrodynamics 2011年第1期23卷 55-64页

作者： ZOU Lin LIN Yu-feng LU Hong school of mechanical and Electronic engineering Wuhan University of Technology Wuhan 430070 China Dep.r.ment of mechanical engineering The Hong Kong Polytechnic University Hong Kong China

A three-dimensional numerical investigation of cross-flow past four circular cylinders in a diamond arrangement at reynolds number of 200 is carried *** the spacing ratios（L /D）ranging from 1.2 to 5.0,the flow patterns can be classified into three basic *** critical spacing ratio for the transition from narrow gap flow pattern to vortex impingement flow pattern around the cylinders is found to beL /D=3.0,while a single bluff-body flow pattern is observed atL /D=*** relationship between the three-dimensional flow patterns and force characteristics around the four cylinders shows that the variation of forces and Strouhal numbers againstL /D are generally governed by these three kinds of flow *** is concluded that the spacing ratio has imp.r.ant effects on the development of the free shear layers about the cylinders and hence has significant effects on the force and pressure characteristics of the four cylinders with different spacing ratios.

关键词： four cylinders spacing ratio flow pattern force characteristics

A novel evolving model for power grids

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Science china(Technological Sciences) 2010年第10期53卷 2862-2866页

作者： LIU Xuan, LIU TianQi & LI XingYuan school of electrical engineering and Automation, Sichuan University, Chengdu 610065, china 1. school of electrical engineering and Automation Sichuan University Chengdu 610065 China

In this pap.r.a novel power grid evolving model,which can well describe the evolving prop.r.y of power grids,is presented. Based on the BA model,motivated by the fact that in real power grids,connectivity of node not only depends on its degree,but also is influenced by many uncertain factors,so we introduce the subconnection factor K for each node. Using the mean-field theory,we get the analytical expression of power-law degree distribution with the exponent γ∈ (3,∞ ). Finally,simulation results show that the new model can provide a satisfactory description for emp.r.cal characteristics of power network,and power network falls somewhere in between scale-free network and uncertain network.

关键词： power grid evolving model scale-free

research on the Long Time Swelling prop.r.ies of poly (vinyl alcohol)/Hydroxylapatite Composite Hydrogel

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Journal of Bionic engineering 2009年第1期6卷 22-28页

作者： De-kun Zhang~(1,3), Da-gang Wang~2, Jun-jie Duan~(1,3), Shi-rong Ge~(2,3)1. school of Materials Science and engineering, china University of Mining and Technology, Xuzhou 221116, p. r. china2. school of mechanical and electrical engineering, china University of Mining and Technology, Xuzhou 221116, p. r. china3. Biotribology Center, National Key Laboratory of Tribology, Tsinghua University, Beijing 100083, p. r. china [a]school of Materials Science and engineering China University of Mining and Technology Xuzhou 221116 P. R. China [b]School of Mechanical and Electrical Engineering China University of Mining and Technology Xuzhou 221116 P. R. China [c]Biotribology Center National Key Laboratory of Tribology Tsinghua University Beijing 100083 P. R. China

poly(vinyl alcohol)/hydroxylapatite(pVA/HA)composite hydrogel was prep.r.d by repeated freezing and *** water loss prop.r.ies of the resultant hydrogel were investigated by using optical *** time immersion tests of pVA/HA composite hydrogel were carried out in the diluted calf serum solution to study the change laws of swelling prop.r.ies with the freezing-thawing cycles and HA *** micro-morphologies of pVA/HA composite hydrogel after long time immersion were observed by means of the high-accuracy 3D *** results show that the swelling process of pVA/HA composite hydrogel is the converse process of its water *** time swelling ratio curves of pVA/HA composite hydrogel in the calf serum solution are manifested as four stages of quick increase,decrease,slow decrease and stable balance,and its equilibrium swelling ratio decreases with the increase of freezing-thawing cycles and HA *** is revealed that the network structure of the composite hydrogel immersed for a long p.r.od is significantly improved with the increase of HA content. p.r.ect network structures of pVA/HA composite hydrogel as well as full and equilibrium tissues after swelling equilibrium are obtained when the HA content is 3% and the number of freezing-thawing cycles is 7.

关键词： poly (vinyl alcohol) hydroxyapatite composite hydrogel swelling prop.r.y morphology

Friction compensation design based on state observer and adaptive law for high-accuracy positioning system

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progress in Natural Science:Materials International 2006年第2期16卷 147-152页

作者： WANG Ying, XIONG Zhenhua and DING Han (school of mechanical engineering, Shanghai Jiao Tong University, Shanghai 200030, china) [a]school of mechanical engineering Shanghai Jiao Tong University Shangai China

Friction is one of the main factors that affect the positioning accuracy of motion system. Friction compensation based on friction model is usually adopted to eliminate the nonlinear effect of friction. This pap.r.presents a prop.r.ional-plus-derivative (pD) feedback controller with a friction compensator based on LuGre friction model. We also design a state observer to observe the unknown state of LuGre friction model, and adopt a p.r.meter adaptive law and off-line ap.r.ximation to estimate the p.r.meters of LuGre friction model. Comp.r.tive exp.r.ments are carried out among our proposed controller, pD controller with friction compensation based on classical friction model, and pD controller without friction compensation. Exp.r.mental results demonstrate that our proposed controller can achieve better p.r.ormance, especially higher positioning accuracy.

关键词： friction compensation state observer adaptive law linear motor motion control.

STUDY ON SINGULAr CONFIGUrATIONS AND COMpUTEr SIMULATION OF 6r rOBOT

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Chinese Journal of mechanical engineering 2004年第2期17卷 177-180页

作者： Zhang Kai Hu Dejin Liu Chengliang school of mechanical engineering,Shanghai Jiaotong University,Shanghai 200030, china school of mechanical engineering Shanghai Jiaotong University 上海 200030

When robot is at singular configuration, the limited hand velocity wouldrequire some joints with infeasible speeds so as to lead unsafely of the system. A method of solvingthe ap.r.ximate velocity of joint near singular configuration point by adding damped vector isproposed and a modified algorithm is provided. With the analysis of J^(-1) the singularconfigurations of 6r robot are divided into structure boundary singularity , boundary singularity ,inner singularity and wrist singularity. The conditions of singularities of the robot have beenascertained. The computer simulations of the singularities of the robot are developed, which havemany advantages over previous description methods of the singular configurations of robot. With thehelp of boundary singularity analysis, a application in welding trajectory planning checking of therobot has been carried out and the simulation result proved visualized and useful.

关键词： robot Singular configuration Computer simulation