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Adaptive Optimal Output Regulation of Interconnected Singularly Perturbed Systems With Application to Power Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 595-607页

作者： jianguo Zhao Chunyu yang Weinan Gao Linna Zhou Xiaomin Liu the Engineering Research Center of Intelligent Control for Underground Space Ministry of EducationChina University of Mining and TechnologyXuzhou 221116 the School of Information and Control Engineering China University of Mining and TechnologyXuzhou 221116 IEEE the State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China

This article studies the adaptive optimal output regulation problem for a class of interconnected singularly perturbed systems(SPSs) with unknown dynamics based on reinforcement learning(RL).Taking into account the slow and fast characteristics among system states,the interconnected SPS is decomposed into the slow time-scale dynamics and the fast timescale dynamics through singular perturbation *** the fast time-scale dynamics with interconnections,we devise a decentralized optimal control strategy by selecting appropriate weight matrices in the cost *** the slow time-scale dynamics with unknown system parameters,an off-policy RL algorithm with convergence guarantee is given to learn the optimal control strategy in terms of measurement *** combining the slow and fast controllers,we establish the composite decentralized adaptive optimal output regulator,and rigorously analyze the stability and optimality of the closed-loop *** proposed decomposition design not only bypasses the numerical stiffness but also alleviates the *** efficacy of the proposed methodology is validated by a load-frequency control application of a two-area power system.

关键词： Adaptive optimal control decentralized control output regulation reinforcement learning(RL) singularly perturbed systems(SPSs)

A RAISED PANEL METHOD BASED ON NURBS FOR FREE-SURFACE POTENTIAL FLOWS WITH FORWARD SPEED

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Journal of Hydrodynamics 2003年第2期15卷 112-120页

作者： Gao Gao, Ma LingSchool of Transportion, wuhan university of technology, wuhan 430063, china Sch. of Transp. Wuhan Univ. of Technol. Wuhan 430063 China

A raised panel method based on NURBS (Non-Uniform Rational B-Splines) forfree-surface flows with forward speed is presented. In this generalized panel method, NURBS areemployed to represent the body geometry, disturbed free surface, and to express the unknown sourcestrength distribution, on the body surface and above the free surface. Compared with commonhigher-order panel methods, it has no need of adopting local coordinates. NURBS make the geometryrepresentation of the body shape and the wave pattern more precise. Raised panels above the freesurface produce less numerical dispersion error, need less CPU consumption and are helpful andcombined with collocation-point shifting up-stream, can satisfy the radiation condition *** using continuous and discrete Fourier analysis, numerical errors of this method are discussedand a general expression for the errors of numerical damping and dispersion, including the effectsof the vertical distance of singularities to the free surface, the order of singularity distributionrepresented by B-splines in panels, and collocation-point shifting is derived.

关键词： NURBS free-surface flow raised panel method error analysis B-spline

COMPUTER VISION APPLIEDIN THE PRECISION CONTROL SYSTEM

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 87-89页

作者： Zhang Qingying Logistics Engineering Department，wuhan university of technology，wuhan 430063，china Logistics Engineering Departiment Wuhan University of Technology Wuhan 430063

Computer vision and its application in the precision control system arediscussed. In the process of fabricating, the accuracy of the products should be controlledreasonably and completely. The precision should be kept and adjusted according to the information offeedback got from the measurement on-line or out-line in different procedures. Computer vision isone of the useful methods to do this. Computer vision and the image manipulation are presented, andbased on this, a n-dimensional vector to appraise on precision of machining is given.

关键词： Computer vision Measurement Precision Quality of products

Highly active and durable La_(0.6) Ca_(0.4)(CrMnFeCo_(2)Ni)O_(3) high entropy perovskite oxide as electrocatalyst for oxygen evolution reaction in alkaline media

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Journal of Materials Science & technology 2024年第1期168卷 71-78页

作者： Xiaoqiang Ji Fan yang Yunzhu Du Jing Li jianguo Li Qiaodan Hu Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Oxygen evolution reaction(OER)is the imperative reaction for many energy storage and conversion devices such as recharge-able metal-air batteries and electrochemical water splitting[1].OER is a complex 4-electron process with sluggish kinetics and therefore requires electrocatalysts to overcome the high *** oxide(RuO_(2))and iridium oxide(IrO_(2))catalysts can promote the OER process remarkably[2-4],however,their ex-tremely high cost,natural scarcity,and long-term instability con-strain their scale-up application in clean-energy technologies[5,6].It is crucial to develop inexpensive,highly efficient,and durable electrocatalysts for OER.

关键词： entropy alkaline perovskite

STUDY OF HYDRODYNAMIC FORCES OF SHIPS IN NARROW WATERWAY

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维普期刊数据库

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Journal of Hydrodynamics 2003年第4期15卷 113-117页

作者： Zhang Xie-dong, Wu Xiu-heng School of Transportation, wuhan university of technology, wuhan 430063, china Sch. of Transp. Wuhan Univ. of Technol. Wuhan 430063 China

The collision of ships in narrow waterway may occur for a variety of *** hydrodynamic forces between two ships change the maneuvering characteristics of ships *** based on the boundary element method, this paper proposes a calculation method for hydrodynamicinteraction forces between ships under meeting and passing conditions in narrow waterway. Theresults from this method are compared with the existing results obtained from other theoreticalapproaches, and they are in good agreement.

关键词： collision of ships narrow waterway hydro-dynamic interaction boundaryelement method

NUMERICAL INVESTIGATIONS INTO THE FRICTION REDUCTION BY MICROBUBBLES FOR FLAT PLATES

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Journal of Hydrodynamics 2003年第3期15卷 82-88页

作者： Zhan De-xin, Wang Jia-mei, Lin Li-ming School of Transportation, wuhan university of technology, wuhan 430063, china, Sch. of Transp. Wuhan Univ. of Technol. Wuhan 430063 China

The two-dimensional flow on the flat plate with injected microbubbles issimulated using the software, PHOENICS (V3. 2), usually used in the CFD (Computational FluidDynamics). A set of formulas for K-ε turbulence model modified with the presence of microbubbles,is employed. With considering the effect of gravity, interfacial lift, inter-phase friction, virtualmass force and interfacial pressure on the flow with microbubbles, numerical calculations for theinfluence of variable air volume fracton as well as distribution, injecting speed, microbubblediameter and position of introducing microbubbles on the friction reduction are presented. Resultsshow that the friction reduction increases with increasing volume fraction and microbubble diameterwithin the range of 100μm, and that the velocity in the boundary layer with microbubbles is greaterthan that without microbubbles. The order of magnitude and trends of the experimental skin-frictionare reproduced well. The uniform free-stream speed in all cases is 4m/s, giving Reynolds number ofup to 20 million.

关键词： flat plate friction reduction by microbubbles modified K-ε turbulencemodel numerical simulation

A Heuristic Algorithm for QoS Multicast Routing

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Journal of Systems Engineering and Electronics 2002年第4期13卷 73-78页

作者： Li Layuan & Li Chunlin Department of Computer Science, wuhan university of technology, wuhan 430063, P. R. china Department of Computer Science Wuhan University of Technology Wuhan 430063 P. R. China

In recent years, QoS multicast routing has continued to be a very important research topic in the areas of networks. This paper presents a heuristic algorithm for the QoS multicast routing (HAQMR). This heuristic algorithm deals with delay and bandwidth constraints and has low cost. The HAQMR attempts to significantly reduce the overhead for constructing a multicast tree, the proof for correctness of the HAQMR is given, and the performance of the HAQMR is evaluated by simulations. The study shows that HAQMR provides an available approach to QoS multicast routing.

关键词： Heuristic QoS Multicast QoS constraints QoS routing.

Investigating the effect of volatility on the hygroscopicities of acetate nanoparticle aerosols by surface plasmon resonance microscopy

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Journal of Environmental Sciences 2024年第4期138卷 167-178页

作者： Bo yang Zhibo Xie jianguo Liu Huaqiao Gui Jiaoshi Zhang Xiuli Wei Zetao Fan Douguo Zhang Key Laboratory of Environmental Optics and technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China university of Science and technology of china Hefei 230026China CAS Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Advanced Laser technology Laboratory of Anhui Province Department of Optics and Optical EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Under high relative humidity(RH)conditions,the release of volatile components(such as acetate)has a significant impact on the aerosol *** this work,one surface plasmon resonance microscopy(SPRM)measurement system was introduced to determine the hygroscopic growth factors(GFs)of three acetate aerosols separately or mixed with glucose at different *** Ca(CH_(3)COO)_(2) or Mg(CH_(3)COO)_(2) aerosols,the hygroscopic growth trend of each time was lower than that of the previous time in three cyclic humidification from 70% RH to 90% RH,which may be due to the volatility of acetic acid leading to the formation of insoluble hydroxide(Ca(OH)_(2) or Mg(OH)_(2))under high RH *** the third calculated GF(using the Zdanovskii-Stokes-Robinson method)for Ca(CH_(3)COO)_(2) or Mg(CH_(3)COO)_(2) in bicomponent aerosols with 1:1 mass ratio were 3.20% or 5.33% lower than that of the first calculated GF at 90% *** calculated results also showed that the hygroscopicity change of bicomponent aerosol was negatively correlated with glucose content,especially when the mass ratio of Mg(CH_(3)COO)_(2) to glucose was 1:2,the GF at 90% RH only decreased by4.67% after three cyclic *** coupled plasma atomic emission spectrum(ICP-AES)based measurements also indicated that the changes of Mg^(2+)concentration in bicomponent was lower than that of the *** results of this study reveal thatduring the efflorescence transitions of atmospheric nanoparticles,the organic acids diffusion rate may be inhibited by the coating effect of neutral organic components,and the particles aging cycle will be prolonged.

关键词： Hygroscopic growth Volatility Acetate aerosols Nanoparticle aerosol Surface plasmon resonance

A Structured Methodology for Local Network Design Engineering

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Journal of Systems Engineering and Electronics 1992年第1期3卷 64-72页

作者： Li Layuanwuhan university of Water Transportation Engineering, wuhan 430063, china wuhan university of Water Transportation Engineering Wuhan 430063 China

This paper presents a structured methodology for local network design engineering (SMLNDE). A complex and fuzzy project for local network design can be decomposed into a set of simple and particular activities using the SMLNDE. The SMLNDE allows rigorous requirements definition and permits the exhaustive consideration of the large number of factors influencing local network design engineering. The complete and clear design documentations and an optimal design can also be provided by the methodology. The SMLNDE has been implemented using the structured analysis and design technique. The study shows that the SMLNDE is an effective design methodology for the large and complex local networks.

关键词： Local network Design engineering Structured methodology.