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Journal of Iron and Steel Research International 2016年第12期23卷 1268-1276页

作者： Wei-gang LI Chao LIU Ning FENG Xi CHEN Xiang-hua LIU College of Information Science and Engineering Wuhan University of Science and Technology Research Institute of Science and Technology Northeastern University

A mathematical model of friction coefficient was proposed for the roll force calculation of hot-rolled strips. The online numerical solving method of the roll force calculation formula based on the proposed friction model was developed and illustrated by the practical calculation case. Then, the friction coefficient during hot strip rolling was estimated from the measured roll force by force model inversion. And then, the expression of friction model was pro posed by analyzing the calculation process of stress state coefficient, and the model parameters were determined by the shared parameter multi-model nonlinear optimization method. Finally, the industrial experiments demonstrated the feasibility and effectiveness of the related models. The accuracy of the new roll force model based on the built friction model was much higher than that of the traditional Sims model, and it could be applied in the online hot rolling process control.

关键词： hot rolling roll force friction coefficient soft measurement multi objective optimization

Influence of yaw damper layouts on locomotive lateral dynamics performance:Pareto optimization and parameter analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第5期24卷 450-464页

作者： Guang LI Yuan YAO Longjiang SHEN Xiaoxing DENG Wensheng ZHONG State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China Bogie R&D Department of CRRC Zhuzhou Electric Locomotive Co. Ltd.Zhuzhou 412001China

High-speed locomotives are prone to carbody or bogie hunting when the wheel-rail contact conicity is excessively low or *** can cause negative impacts on vehicle dynamics *** study presents four types of typical yaw damper layouts for a high-speed locomotive(Bo-Bo)and compares,by using the multi-objective optimization method,the influences of those layouts on the lateral dynamics performance of the locomotive;the linear stability indexes under lowconicity and high-conicity conditions are selected as optimization ***,the radial basis function-based highdimensional model representation(RBF-HDMR)method is used to conduct a global sensitivity analysis(GSA)between key suspension parameters and the lateral dynamics performance of the locomotive,including the lateral ride comfort on straight tracks under the low-conicity condition,and also the operational safety on curved *** is concluded that the layout of yaw dampers has a considerable impact on low-conicity stability and lateral ride comfort but has little influence on curving *** is also an important finding that only when the locomotive adopts the layout with opening outward,the difference in lateral ride comfort between the front and rear ends of the carbody can be eliminated by adjusting the lateral installation angle of the yaw ***,force analysis and modal analysis methods are adopted to explain the influence mechanism of yaw damper layouts on the lateral stability and differences in lateral ride comfort between the front and rear ends of the carbody.

关键词： High-speed locomotive Yaw damper layout Lateral stability Lateral ride comfort multi objective optimization Global sensitivity analysis(GSA)

ON CONE D.C. optimization AND CONJUGATE DUALITY

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Chinese Annals of Mathematics,Series B 2003年第4期24卷 521-528页

作者： M.SEMU Institut fut Statistik und Mathematische Wirtschaftstheorie Universitat Karlsruhe76128 KarlsruheGermany.

This paper derives first order necessary and sufficient conditions for unconstrained coned.c. Programming problems where the underlined space is partially ordered with respect to acone. These conditions are given in terms of directional derivatives and subdifferentials of thecomponent functions. Moreover, conjugate duality for cone d.c. optimization is discussed andweak duality theorem is proved in a more general partially ordered linear topological vectorspace (generalizing the results in [11]).

关键词： multi objective optimization Cone d.c. programming Optimality conditions Conjugate duality

Research on Comprehensive Control of Power Quality of Port Distribution Network Considering Large-Scale Access of Shore Power Load

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Energy Engineering 2023年第5期120卷 1185-1201页

作者： Yuqian Qi Mingshui Li Yu Lu Baitong Li Tianjin University Tianjin300110China

In view of the problem of power quality degradation of port distribution network after the large-scale application of shore power load,a method of power quality management of port distribution network is *** on the objective function of the best power quality management effect and the smallest investment cost of the management device,the optimization model of power quality management in the distribution network after the large-scale application of large-capacity shore power is *** on the balance between the economic demand of distribution network resources optimization and power quality management capability,the power quality of distribution network is considered *** proposed optimization algorithm for power quality management based on Matlab and OpenDSS is proposed and analyzed for port distribution *** simulation results show that the proposed optimizationmethod can maximize the power qualitymanagement capability of the port distribution network,and the proposed optimization algorithm has good convergence and global optimization finding capability.

关键词： Shore power harmonic control multi objective optimization particle swarm optimization algorithm

optimization approach hydroforming car beam billets based grey system theory

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Journal of Beijing Institute of Technology 2011年第1期20卷 48-53页

作者：吴耀金薛勇段江年 National Key Laboratory of Science and Technology on Electronic Test and Measurement School of Material Science and Engineering North University of China School of Mechanical Engineering and Automation Beijing University of Aeronautics and Astronautics

Perfect combination of structural size parameters of the hydroforming billets is essential to obtain even wall thicknesses of the car beam. Finite element （ FE ） analysis on hydroforming car beam was carried out, and the results were optimized according to multiple quality objectives by the grey system theory. With bending angle, bending radius and hight difference along the axis direction as variables, orthogonal FE analyses were conducted and the minimum and maximum wall thicknes ses of the billets with different sizes were obtained. Taking the minimum and maximum wall thick nesses as two references, the correlation coefficient between the data for reference and those for comparison by the grey system theory reduced multi objectives to a single quality objective, and the average correlation level of every billet facilitated the optimization of size parameters for hydroform ing car beam. The trial production showed that the optimization approach satisfied the need of hy droforming car beams.

关键词： car beam hydroforming billet grey system theory multi objective optimization

optimization with Genetic Algorithms of PVT System Global Efficiency

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Journal of Energy and Power Engineering 2012年第7期6卷 1035-1041页

作者： Giampietro Fabbri Matteo Greppi Marco Lorenzini Department of Energy Nuclear and Environmental Protection Bologna University Bologna 40136 Italy Faculty of Engineering Bologna University Forli 47100 Italy

PV （photovoltaic） solar panels generally produce electricity in the 6% to 12% efficiency range, the rest is being dissipated in thermal losses. To recover this amount, hybrid photovoltaic thermal systems （PV/T） have been devised. These are devices that simultaneously convert solar energy into electricity and heat. It is thus interesting to study the PV/T system as part of a closed loop single phase water CDU （coolant distribution unit） in laminar forced convection. In particular, the analysis was conducted on the optimal cooling performance of the thermal part, testing polynomial channel profiles of varying order （from zero to fourth） for channels of a real industrial module heat sink, under the following conditions： ideal flux of 1,000 W/m2 on one side, insulation on the opposite side, periodic conditions on the remaining sides, fully developed thermal and velocity profile in laminar flow of water. Through the use of a genetic algorithm, we have optimized the shape of the channel＇s sidewalls in terms of heat transfer maximization. In terms of Nusselt number, results show that fourth order profiles are the most efficient. When limits to allowable pressure loss and module weight are introduced, these bring generally to a lower efficiency of the system than the unconstrained case.

关键词： Fins genetic alghoritms multi objective optimization cooling PVT systems.

Application of Grade Algorithm Based Approach along with PV Analysis for Enhancement of Power System Performance

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Circuits and Systems 2016年第10期7卷 3354-3370页

作者： G. Kannan D. Padma Subramaniam Solai Manokar Department of Electrical and Electronics Engineering Amet University Chennai India Sri Muthukumaran Institute of Technology Chennai India Department of Electrical and Electronics Engineering Anand Institute of Higher Technology Chennai India

This paper presents an application of GRADE Algorithm based approach along with PV analysis to solve multi objective optimization problem of minimizing real power losses, improving the voltage profile and hence enhancing the performance of power system. GRADE Algorithm is a hybrid technique combining genetic and differential evolution algorithms. Control variables considered are Generator bus voltages, MVAR at capacitor banks, transformer tap settings and reactive power generation at generator buses. The optimal values of the control variables are obtained by solving the multi objective optimization problem using GRADE Algorithm programmed using M coding in MATLAB platform. With the optimal setting for the control variables, Newton Raphson based power flow is performed for two test systems, viz, IEEE 30 bus system and IEEE 57 bus system for three loading conditions. Minimization of Real power loss and improvement of voltage profile obtained are compared with the results obtained using firefly and particle swarm optimization (PSO) techniques. Improvement of Loadability margin is established through PV curve plotted using continuation power flow with the real power load at the most affected bus as the bifurcation parameter. The simulated output shows improved results when compared to that of firefly and PSO techniques, in term of convergence time, reduction of real power loss, improvement of voltage profile and enhancement of loadability margin.

关键词： multi objective optimization GRADE Algorithm Loadability Margin PV Curve Real Power Loss Minimization Voltage Profile Improvement

Lightweight optimization for Engine Hood Based on Forward Design

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Lightweight Optimization for Engine Hood Based on Forward De...

multi-objective Firefly Algorithm for Test Data Generation with Surrogate Model

2019中国汽车工程学会年会

作者： Wang Chuanqing Zhang Liling Tian Lei Jia Cunli Baic Motor Corporation Ltd.Research and Design Center

The load path and main section is constructed based on forward *** hood inner plate is set as weight reduction *** main load path is obtained by topology *** the finite element model is reset based on topology optimized *** the parametric hood is established based on the reset finite element *** main sections of strengthening rib and frame are set as design *** are10 design variables in the engine hood *** samples are generated by Optimal Latin hypercube design（Opt LHD）.The surrogate model is constructed by Radial Basis Function（RBF）.The optimized solution is obtained by Non-Dominated Sorting Genetic Algorithm（NSGA-Ⅱ）.Forward design could obtain the reasonable load path and main section ***,the optimization solution has better lightweight *** forward design,the mass of engine hood inner plate reduce0.585 kg,the lightweight rate as high as 9.16%.The bend stiffness,torsion stiffness,lateral stiffness and corner stiffness of optimized engine hood satisfy objectives.

关键词： engine hood lightweight multi objective optimization parametric model

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国际计算机前沿大会会议论文集 2021年第1期 283-299页

作者： Wenning Zhang Qinglei Zhou Chongyang Jiao Ting Xu State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou 450000China Zhongyuan University of Technology Zhengzhou 450000China Zhengzhou University Zhengzhou 450000China

To solve the emerging complex optimization problems, multi objectiveoptimization algorithms are needed. By introducing the surrogate model forapproximate fitness calculation, the multi objective firefly algorithm with surrogatemodel (MOFA-SM) is proposed in this paper. Firstly, the population wasinitialized according to the chaotic mapping. Secondly, the external archive wasconstructed based on the preference sorting, with the lightweight clustering pruningstrategy. In the process of evolution, the elite solutions selected from archivewere used to guide the movement to search optimal solutions. Simulation resultsshow that the proposed algorithm can achieve better performance in terms ofconvergence iteration and stability.

关键词： Firefly algorithm multi objective optimization Surrogate model Test data generation