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Journal of Sy.tems Science & Complexity 2019年第4期32卷 1093-1103页

作者： she Weiqiang MA Mihua Department of Public Teaching Zhangzhou Institute of TechnologyZhangzhou 363000China School of Mathematics and Statistics Minnan Normal UniversityZhangzhou 363000China

An impulsive control scheme is proposed to investigate the tracking sy.chronization of ring and inline networked Lagrangian *** a time-vary.ng target trajectory.some algebraic sy.chronization criteria are derived to make the networked Lagrangian sy.tems sy.chronize to the target trajectory.A distinctive feature of the proposed work is that the impulsive control scheme is used to investigate the highly.nonlinear Lagrangian *** the impulsive control,each agent described by.the Lagrangian sy.tem instantaneously.interacts with its neighbors only.at some discrete ***,the proposed control strategy.requires only.local coupling feedback for global *** a direct application of the obtained theoretical results,the tracking sy.chronization of multiple 3-DOF mobile robots is discussed in detail and *** results verify.the effectiveness of the proposed control strategy.

关键词： Impulsive control mobile robots networked lagrangian sy.tems tracking sy.chronization

A power plant for integrated waste energy.recovery.from liquid air energy.storage and liquefied natural gas

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Chinese Journal of Chemical Engineering 2021年第6期34卷 242-257页

作者： Tongtong Zhang Xiaohui she y.long Ding birmingham Centre for Energy.Storage&School of Chemical Engineering University of BirminghamBirmingham B152TTUK

Liquefied natural gas(LNG)is regarded as one of the cleanest fossil fuel and has experienced significant developments in recent *** liquefaction process of natural gas is energy.intensive,while the regasification of LNG gives out a huge amount of waste energy.since plenty.of high grade cold energy.-160℃)from LNG is released to sea water directly.in most cases,and also sometimes LNG is burned for *** the other hand,liquid air energy.storage(LAES)is an emerging energy.storage technology.for applications such as peak load shifting of power grids,which generates 30%-40%of compression heat(-200℃).Such heat could lead to energy.waste if not recovered and *** recovery.of the compression heat is technically.feasible but requires additional capital investment,which may.not alway. be economically.***,we propose a power plant for recovering the waste cry.genic energy.from LNG regasification and compression heat from the *** challenge for such a power plant is the wide working temperature range between the low-temperature exergy.source(-160℃)and heat source(-200℃).Nitrogen and argon are proposed as the working fluids to address the *** analy.es are carried out and the results show that the power plant could achieve a thermal efficiency.of 27%and 19%and an exergy.efficiency.of 40%and 28%for nitrogen and argon,***,with the nitrogen as working fluid undergoes a complete bray.on Cy.le,while the argon based power plant goes through a combined bray.on and Rankine ***,the economic analy.is shows that the pay.ack period of this proposed sy.tem is only.2.2 y.ars,utilizing the excess heat from a 5 MW/40 MWh LAES *** findings suggest that the waste energy.based power plant could be co-located with the LNG terminal and LAES plant,providing additional power output and reducing energy.waste.

关键词： Waste energy.recovery Power plant Liquid air energy.storage Liquefied natural gas Integration

Sub-ensemble study.of pressure gradient effects on the variation of Karman constant

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Science China(Phy.ics,Mechanics & Astronomy. 2012年第8期55卷 1439-1444页

作者： WANG y.nZhi she ZhenSu State Key.Laboratory.for Turbulence and Complex Sy.tems and Department of Mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China

Using data from direct numerical simulation （DNS） of incompressible and compressible channel flow, we develop a method of sub-ensemble decomposition to investigate the pressure gradient effect on the Karman constant and the additive constant b characterizing the mean velocity.profile （MVP）. The sub-ensemble decomposition is defined according to the magnitude of vertical fluctuation velocity. which mimics coherent motions like ejection and sweep. DNS data analy.is shows that each sub-ensemble display. a distinct Karman constant, with a variation which mimics effects of pressure gradient. The latter is demonstrated by.a relation between sub-ensembles＇ km and bm similar to empirical data under various pressure gradients. A set of global parameters, k0-pg=0.39 ＆ b0-pg=5.5, are then derived for interpreting two constants observed by.Nagib et al.

关键词： sub-ensemble vertical fluctuation velocity pressure gradient Karman constant

Perturbation solutions of relativistic viscous hy.rody.amics for longitudinally.expanding fireballs

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Chinese Phy.ics C 2020年第8期44卷 164-171页

作者： Ze-Fang Jiang Duan she C.b.y.ng Defu Hou Department of Phy.ics and Electronic-Information Engineering Hubei Engineering UniversityXiaogan 432000China Institute of Particle Phy.ics&Key.Laboratory.of Quark and Lepton Phy.ics MOECentral China Normal UniversityWuhan 430079China Phy.ics Department and Center for Exploration of Energy.and Matter Indiana University2401 N Milo B.Sampson LaneBloomingtonIN 47408USA

The solutions of the relativistic viscous hy.rody.amics for longitudinally.expanding fireballs are investig-ated with the Navier-Stokes theory.and Israel-Stewart *** energy.and the Euler conservation equations for the viscous fluid are derived in Rindler coordinates,by.assuming that the longitudinal expansion effect is *** the perturbation assumption,an analy.ical perturbation solution for the Navier-Stokes approximation and numerical solutions for the Israel-Stewart approximation are *** temperature evolution with both shear viscous ef-fect and longitudinal acceleration effect in the longitudinal expanding framework are *** specific temper-ature profile shows sy.metric Gaussian shape in the Rindler ***,we compare the results from the Israel-Stewart approximation with the results from the bjorken and the Navier-Stokes approximations,in the pres-ence of the longitudinal acceleration expansion *** found that the Israel-Stewart approximation gives a good description of the early.stage evolutions than the Navier-Stokes theory.

关键词： heavy.ion collision longitudinal expanding fireball viscous hy.rody.amics Rindler coordinate

A moment-based stochastic edge-based smoothed finite element method for electromagnetic forming process

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Science China(Technological Sciences) 2020年第9期63卷 1739-1750页

作者： y.NG Qin WANG bing LI she CUI Xiangy.ng State Key.Laboratory.of Advanced Design and Maufacturing for Vehicle body Hunan UniversityChangsha 410082China

In this paper, a novel stochastic method named as the moment-based stochastic edge-based finite element method(MSES-FEM)is proposed to deal with the uncertain electromagnetic problems. First, electromagnetic and mechanical field are formulated by.smoothed Galerkin Weak Form under edge-based smoothed finite element method(ES-FEM) scheme. The moment analy.is is then applied to obtain the first four moments of the responses and to observe the effects of each random variable on electromagnetic field responses. The maximum entropy.theory.is employ.d to calculate the probability.density.functions(PDFs) of the responses. A quasi-static electromagnetic problem and a practical electromagnetic forming problem(EMF) are performed. The proposed method successfully.solves stochastic electromagnetic forming analy.is under the uncertain parameters. Numerical results obtained by.the proposed MSES-FEM are quite satisfactory.with the ones by.the Monte Carlo simulation(MCS).

关键词： MSES-FEM electromagnetic forming problem the moment analy.is the maximum entropy.theory probability.density.function

Development of electric cart for improving walking ability.— application of control theory.to assistive technology

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Science China(Information Sciences) 2017年第12期60卷 262-270页

作者： Jinhua she y.suhiro OHy.MA Min WU Hiroshi HASHIMOTO School of Engineering Tokyo University of Technology School of Automation China University of Geosciences Hubei Key.Laboratory.of Advanced Control and Intelligent Automation for Complex Sy.tems Master Program of Innovation for Design & Engineering Advanced Institute of Industrial Technology

This paper explains the development of an electric cart that helps the elderly.maintain or improve their phy.ical strength. Unlike commercially.available ones, it has a pedal unit that provides some exercise for a user in training his lower limbs. An impedance model describes the feeling of pushing the pedals. The largest pedal load is determined based on a pedaling experiment. An H∞ controller is designed for each of the largest pedal load and virtually.no load. A control law, which is based on the concept of dy.amic parallel distributed compensation, is designed using the rating of perceived exertion of a driver as a criterion to choose a pedal load between the largest and almost zero. Five university.students and twelve elderly.people participated experiments to verify.the sy.tem design and the validity.of the sy.tem.

关键词： aging borg’s scale dy.amic parallel distributed compensation electrical cart H_∞ control Karvonen formula lower limbs pedaling rating of perceived exertion

Estimation and compensation of periodic disturbance using internal-model-based equivalent-input-disturbance approach

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Science China(Information Sciences) 2022年第8期65卷 150-163页

作者： Qicheng MEI Jinhua she Zhentao LIU Min WU School of Automation China University of Geosciences Hubei Key.Laboratory.of Advanced Control and Intelligent Automation for Complex Sy.tems School of Engineering Tokyo University of Technology

This paper presents an improved equivalent-input-disturbance(EID) approach to deal with periodic disturbances. The approach has two degrees of freedom. One is an improved EID compensator, in which a repetitive controller is inserted in this study. The other is a conventional servo sy.tem for a reference *** improved EID compensator estimates and compensates for periodic disturbances without steady.state error, and the servo sy.tem ensures a satisfactory.tracking performance. The improved EID compensator is designed using the linear-matrix-inequality.LMI) method. Three parameters in an LMI are selected using the particle-swarm-optimization(PSO) algorithm. The state-feedback gain of the conventional servo sy.tem is designed using the linear-quadratic-regulator(LQR) method. Simulation results of a rotational control sy.tem demonstrate the validity.of the approach and its advantage over others.

关键词： equivalent input disturbance (EID) linear matrix inequality.(LMI) linear quadratic regulator (LQR) particle swarm optimization (PSO) periodic disturbance repetitive control

Discrete wavelet structure and discrete energy.of classical plane light waves

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Chinese Phy.ics b 2021年第4期30卷 139-143页

作者： Xing-Chu Zhang Wei-Long she Department of Phy.ics and Information Engineering Guangdong University of EducationGuangzhou 510303China School of Phy.ics Sun Yat-Sen UniversityGuangzhou 510275China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

We find by.the wavelet transform that the classical plane light wave of linear polarization can be decomposed into a series of discrete Morlet *** the theoretical frame,the energy.of the classical light wave becomes discrete;interestingly.the discretization is consistent with the energy.division of P portions in Planck radiation theory.where P is an *** is shown that the changeable energy.of a basic plane light wave packet or wave train is H_(0k)=nP0 kω(n=1,2,3,...;k=|k|),with discrete wavelet structure parameter n,wave vector k and idler frequency.ω,and a constant p0 *** wave-particle duality.from the Mach-Zehnder interference of single photons is simulated by.using random basic plane light wave packets.

关键词： classic plane light wave discrete wavelet structure discrete energy

Design of a Discrete-time Output-feedback based Repetitive-control Sy.tem

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International Journal of Automation and computing 2013年第4期10卷 343-349页

作者： Lan Zhou Jin-Hua she Min Wu School of Information and Electrical Engineering Hunan University of Science and Technology School of Computer Science Tokyo University of Technology School of Information Science and Engineering Central South University

This paper deals with the problem of designing a robust discrete output-feedback based repetitive-control sy.tem for a class of linear plants with periodic uncertainties. The periodicity.of the repetitive-control sy.tem is exploited to establish a two-dimensional （2D） model that converts the design problem into a robust stabilization problem for a discrete 2D sy.tem. by.employ.ng Ly.punov stability.theory.and the singular-value decomposition of the output matrix, a linear-matrix-inequality.（LMI） based stability.condition is derived. The condition can be used directly.to design the gains of the repetitive controller. Two tuning parameters in the LMI enable the preferential adjustment of control and learning. A numerical example illustrates the design procedure and demonstrates the validity.of the method.

关键词： Repetitive control discrete two-dimensional sy.tem singular-value decomposition output feedback linear matrix in- equality.(LMI).