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Error-based adaptive optimal tracking control of nonlinear discrete-time systems

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Science China(Information Sciences) 2024年第1期67卷 154-167页

作者： Chun LI Jinliang DING Frank L.LEWIS Tianyou CHAI State Key Laboratory of Synthetical Automation for Process Industries Northeastern University UTA Research Institute The University of Texas at Arlington

In this paper,for the output tracking problem of nonlinear discrete-time systems,a performance index is newly defined using the adaptive dynamic programming(ADP) technique to completely eliminate tracking errors in *** contrast to traditional definitions of performance indices in other ADP-based methods,the proposed performance index is not only designed from the perspective of output tracking errors but also introduced errors of system states and control inputs at adjacent stages,which is suitable for practical situations in many industrial applications,such as the alumina production,the flotation process,and the mineral grinding *** proved that the obtained controller can make the system output fully track the given reference trajectory by applying the iterative criteria of the ADP *** addition,the proposed algorithm was implemented using a data-driven technique and neural networks to avoid analyzing and deducing the complicated dynamics of actual industrial ***,using historical data for a forced-circulation evaporation system in the alumina production process,the effect of the proposed approach was verified through a numerical simulation and compared with that of the proportional-integral controller.

关键词： adaptive dynamic programming iterative criteria performance index tracking errors tracking problem

Different effects of economic and structural performance indexes on model construction of structural topology optimization

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Acta Mechanica Sinica 2015年第5期31卷 777-788页

作者： G.L.Yi Y.K.Sui College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology Department of Mechanical and Aerospace Engineering Seoul National University

The objective and constraint functions related to structural optimization designs are classified into economic and performance indexes in this *** influences of their different roles in model construction of structural topology optimization are also ***,two structural topology optimization models,optimizing a performance index under the limitation of an economic index,represented by the minimum compliance with a volume constraint（MCVC）model,and optimizing an economic index under the limitation of a performance index,represented by the minimum weight with a displacement constraint（MWDC）model,are *** on a comparison of numerical example results,the conclusions can be summarized as follows：（1）under the same external loading and displacement performance conditions,the results of the MWDC model are almost equal to those of the MCVC model;（2）the MWDC model overcomes the difficulties and shortcomings of the MCVC model;this makes the MWDC model more feasible in model construction;（3）constructing a model of minimizing an economic index under the limitations of performance indexes is better at meeting the needs of practical engineering problems and completely satisfies safety and economic requirements in mechanical engineering,which have remained unchanged since the early days of mechanical engineering.

关键词： Economic index performance index Structural topology optimization models MCVC model MWDC model Safety and economy

Dynamic Analysis and Dimensional Synthesis of Easy-to-Protect Large-Load Robot for Extracting Fermented Grains

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Journal of Beijing Institute of Technology 2023年第4期32卷 529-550页

作者： Yubin Zhang Jinzhu Zhang Congming Li Xiaoyan Xiong Hongjie Du College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024China Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

To improve the operation situation of difficulty and low efficiency in the extraction of fermented grains(FG),a high-load and large-workspace reclaiming robot for ceramic cylinder fermentation is designed,and a reclaiming effector is designed according to the operating ***,the kinematics and singularity of the mechanism are analyzed.A multi-domain polar coordinate search method is proposed to obtain the workspace and the volume of the ***,the dynamic modeling is completed and the example simulation is carried ***,the motion-force transmission index of the mechanism is *** based on the global transmissibility and the good-transmission workspace,the dimensional synthesis of the driving mechanism is completed by using the performance atlas-based ***,aiming at the regular workspace size,stiffness and loading capacity,the Pareto optimal solution set of the executive mechanism dimension is obtained by using the multi-objective particle swarm optimization(MOPSO)*** paper can provide a theoretical basis for the optimal design and control of FG reclaiming robot.

关键词： reclaiming robot configuration design performance index dynamic modeling multi-objective optimization

Noisy component extraction with reference

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Frontiers of Computer Science 2013年第1期7卷 135-144页

作者： Yongjian ZHAO Hong HE Jianxun Mi School of Information Engineering Shandong University Weihai 264209 China Bio-Computing Research Center Shenzhen Graduate School Harbin Institute of Technology Shenzhen 518055 China Key Laboratory of Network Oriented Intelligent Computation Shenzhen 518055 China

Blind source extraction （BSE） is particularly at- tractive to solve blind signal mixture problems where only a few source signals are desired. Many existing BSE methods do not take into account the existence of noise and can only work well in noise-free environments. In practice, the desired signal is often contaminated by additional noise. Therefore, we try to tackle the problem of noisy component extraction. The reference signal carries enough prior information to dis- tinguish the desired signal from signal mixtures. According to the useful properties of Gaussian moments, we incorporate the reference signal into a negentropy objective function so as to guide the extraction process and develop an improved BSE method. Extensive computer simulations demonstrate its validity in the process of revealing the underlying desired signal.

关键词： blind signal processing reference signal Gaus- sian moments negentropy objective function biomedical signal measure performance index

Optimal design theories of tuned mass dampers with nonlinear viscous damping

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Earthquake Engineering and Engineering Vibration 2009年第4期8卷 547-560页

作者： Lap-Loi Chung Lai-Yun Wu Hsu-Hui Huang Chung-Hsin Chang Kuan-Hua Lien Center for Research on Earthquake Engineering （NCREE） Chinese Taipei Department of Civil Engineering Taiwan University. Chinese Taipei

Optimal design theory for linear tuned mass dampers （TMD） has been thoroughly investigated, but is still under development for nonlinear TMDs. In this paper, optimization procedures in the time domain are proposed for design of a TMD with nonlinear viscous damping. A dynamic analysis of a structure implemented with a nonlinear TMD is conducted first. Optimum design parameters for the nonlinear TMD are searched using an optimization method to minimize the performance index. The feasibility of the proposed optimization method is illustrated numerically by using the Taipei 101 structure implemented with TMD. The sensitivity analysis shows that the performance index is less sensitive to the damping coefficient than to the frequency ratio. Time history analysis is conducted using the Taipei 101 structure implemented with different TMDs under wind excitation. For both linear and nonlinear TMDs, the comfort requirements for building occupants are satisfied as long as the TMD is properly designed. It was found that as the damping exponent increases, the relative displacement of the TMD decreases but the damping force increases.

关键词： optimal design theory tuned mass damper (TMD) nonlinear performance index sensitivity analysis Taipei 101

Analysis and optimum design of rider-bicycle mechanisms:Design of bicycle parameters for a specified rider

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Science China(Technological Sciences) 2011年第11期54卷 3027-3034页

作者： LIU XinJun WANG Jing YU WeiYang WU JinHua State Key Laboratory of Tribology and Institute of Manufacturing Engineering Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

Optimum design of rider-bicycle mechanisms is very important for customizing bicycles and plays a crucial role in the improvement of athletes' performances and in protection of the *** the birth of the first bicycle,people have been keeping optimizing bicycles with respect to physical conditions of *** modern design,the basic structure of a bicycle has been formulized,while many geographic parameters remain *** this paper,the bicycle and the human body are considered as a kinematic mechanism,called rider-bicycle *** optimum design is implemented from the perspective of ***-saving and comfortableness are considered at the same *** corresponding performance charts are drawn and the relationship between the performances and parameters of seat height,crank length and body parameters are *** using these charts,the optimal design method of bicycle's parameters for a specified person is then *** solutions to get suitable seat height and crank length for a person are obtained *** research is of significance for customizing bicycles and design of bicycle robot.

关键词： optimum design rider-bicycle mechanism performance index performance chart

Measuring the social performance of forest management

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Journal of Forestry Research 2021年第5期32卷 1803-1818页

作者： Timo Pukkala University of Eastern Finland P.O.Box 11180101 JoensuuFinland

Forests produce several types of benefits to both forest landowners and *** social benefit of private forestry is equal to private benefit plus positive externalities minus negative *** study developed alternative metrics for the evaluation of the social benefit of forest *** management was assessed in terms of five criteria:economic,socio-cultural,environmental and ecological performance and the resilience of the forest *** criterion was described with three numerical *** performance indices were calculated from the indicator values using methods developed for multi-criteria decision *** was concluded that indices based on the multiplicative Cobb-Douglas utility function might be the most recommendable when forestry should produce a balanced combination of different ecosystem *** the indices were used to compare alternative silvicultural systems in terms of their social performance,continuous cover management was ranked better than even-aged *** performance of even-aged management improved when it aimed at increasing the share of mixed stands and broadleaf *** net present value(NPV) with a 1 % discount rate led to better social performance than maximizing NPV with a 4% discount rate.

关键词： Efficiency analysis Acceptability Sustainable forestry performance index Utility function Multi-criteria analysis Continuous cover forestry Evenaged forestry Resilience

Effect of seismic retrofit of bridges on transportation networks

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Earthquake Engineering and Engineering Vibration 2003年第2期2卷 169-179页

作者： Masanobu Shinozuka Yuko Murachi Michal J.Orlikowski Department of Civil and Environmental Engineering University of CaliforniaIrvineUSA Distinguished Professor and Chair Department of Civil and Environmental Engineering University of CaliforniaIrvineUSA Research Associate Department of Civil and Environmental Engineering Princeton UniversityUSA Undergraduate Student.

The objective of this research is to determine the effect earthquakes have on the performance of transportation network *** do this,bridge fragility curves,expressed as a function of peak ground acceleration(PGA)and peak ground velocity(PGV),were *** damage was evaluated under the 1994 Northridge earthquake and scenario earthquakes.A probabilistic model was developed to determine the effect of repair of bridge damage on the improvement of the network performance as days passed after the *** an example,the system performance degradation measured in terms of an index,'Drivers Delay,'is calculated for the Los Angeles area transportation system,and losses due to Drivers Delay with and without retrofit were estimated.

关键词： fragility curves seismic retrofit probabilistic model bridges transportation networks drivers delay performance index Northridge earthquake.

Intelligent PID Control of Pneumatic Rotary Actuator Angle Servo-System

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Journal of Beijing Institute of Technology 2003年第S1期12卷 16-19页

作者：王鹏彭光正伍清河 Department of Automatic Control School of Information Science and TechnologyBeing Institute of TechnologyBeijing 100081China

In order to solve the problems that make the orientation of pneumatic rotary actuator inaccurate, a newly intelligent PID control algorithm is proposed. Pneumatic rotary actuator angle servo-system uses electropneumatic proportional valve as control device, which changes the pressure of cavity and then pushes the actuator to revolve to the expected position. Using intelligent PID control algorithm, several special methods were put forward to overcome the connatural shortcomings of pneumatic system and make the rotary actuator track the expected value timely and accurately. Experimental results have shown that by using this intelligent algorithm, the performance index of system was improved greatly.

关键词： pneumatic rotary actuator angle control system intelligent arithmetic performance index