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IEEE/cAA Journal of Automatica Sinica 2024年第3期11卷 649-660页

作者： Meilin Li Yue Long Tieshan Li Hongjing Liang c.L.Philip chen the School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China IEEE the Yangtze Delta Region Institute University of Electronic Science and Technology of ChinaHuzhou 313000 the Laboratory of Electromagnetic Space cognition and Intelligent control Beijing 100089China the School of computer Science and Engineering South China University of TechnologyGuangzhou 510006

This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).consider the MASs with small-scale networks where a centralized dynamic ETM with global information of the MASs is first designed.Then,a distributed dynamic ETM which only uses local information is developed for the MASs with large-scale networks.It is shown that the semi-global consensus of the MASs can be achieved by the designed bounded control protocol where the Zeno phenomenon is eliminated by a designable minimum inter-event time.In addition,it is easier to find a trade-off between the convergence rate and the minimum inter-event time by an adjustable parameter.Furthermore,the results are extended to regional consensus of the MASs with the bounded control protocol.Numerical simulations show the effectiveness of the proposed approach.

关键词： constrained input designable minimum inter-event time directed communication topology dynamic event-triggered mechanism MASs consensus control

Adaptive neural network control of a 2-DOF helicopter system considering input constraints and global prescribed performance

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Science china(Information Sciences) 2024年第7期67卷 224-239页

作者： Zhijia ZHAO Jiale WU Zhijie LIU We HE c.L.Philip chen School of Mechanical and Electrical Engineering Guangzhou University School of Intelligence Science and Technology and Key Laboratory of Intelligent Bionic Unmanned Systems of Ministry of Education University of Science and Technology Beijing School of computer Science and Engineering South China University of Technology Pazhou Lab

In this study, an adaptive neural network(NN) control is proposed for nonlinear two-degree-offreedom(2-DOF) helicopter systems considering the input constraints and global prescribed performance.First, radial basis function NN(RBFNN) is employed to estimate the unknown dynamics of the helicopter system. Second, a smooth nonaffine function is exploited to approximate and address nonlinear constraint functions. Subsequently, a new prescribed function is proposed, and an original constrained error is transformed into an equivalent unconstrained error using the error transformation and barrier function transformation methods. The analysis of the established Lyapunov function proves that the controlled system is globally uniformly bounded. Finally, the simulation and experimental results on a constructed Quanser's test platform verify the rationality and feasibility of the proposed control.

关键词： adaptive NN control 2-DOF helicopter global prescribed performance input constraints

Liquefaction susceptibility and deformation characteristics of saturated coral sandy soils subjected to cyclic loadings-a critical review

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 261-296页

作者： chen Guoxing Qin You Ma Weijia Liang Ke Wu Qi c.Hsein Juang Institute of Geotechnical Engineering Nanjing Tech UniversityNanjing 210009China civil Engineering and Earthquake Disaster Prevention center of Jiangsu Province Nanjing 210009China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China college of civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 210016China Glenn Department of civil Engineering Clemson UniversityClemsonSC 29634USA

coral sandy soils widely exist in coral island reefs and seashores in tropical and subtropical regions.Due to the unique marine depositional environment of coral sandy soils,the engineering characteristics and responses of these soils subjected to monotonic and cyclic loadings have been a subject of intense interest among the geotechnical and earthquake engineering communities.This paper critically reviews the progress of experimental investigations on the undrained behavior of coral sandy soils under monotonic and cyclic loadings over the last three decades.The focus of coverage includes the contractive-dilative behavior,the pattern of excess pore-water pressure(EPWP)generation and the liquefaction mechanism and liquefaction resistance,the small-strain shear modulus and strain-dependent shear modulus and damping,the cyclic softening feature,and the anisotropic characteristics of undrained responses of saturated coral sandy soils.In particular,the advances made in the past decades are reviewed from the following aspects:(1)the characterization of factors that impact the mechanism and patterns of EPWP build-up;(2)the identification of liquefaction triggering in terms of the apparent viscosity and the average flow coefficient;(3)the establishment of the invariable form of strain-based,stress-based,or energy-based EPWP ratio formulas and the unique relationship between the new proxy of liquefaction resistance and the number of cycles required to reach liquefaction;(4)the establishment of the invariable form of the predictive formulas of small strain modulus and strain-dependent shear modulus;and(5)the investigation on the effects of stress-induced anisotropy on liquefaction susceptibility and dynamic deformation characteristics.Insights gained through the critical review of these advances in the past decades offer a perspective for future research to further resolve the fundamental issues concerning the liquefaction mechanism and responses of coral sandy sites subjected to cyclic loadings associated with seismic eve

关键词： liquefaction susceptibility dynamic deformation characteristics coral sandy soil cyclic loading review and prospect

Layer Hall effect induced by hidden Berry curvature in antiferromagnetic insulators

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National Science Review 2024年第2期11卷 15-23页

作者： Rui chen Hai-Peng Sun Mingqiang Gu chun-Bo Hua Qihang Liu Hai-Zhou Lu X.c.Xie Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology(SUSTech) International Quantum Academy Institute for Theoretical Physics and Astrophysics University of Würzburg School of Electronic and Information Engineering Hubei University of Science and Technology Guangdong Provincial Key Laboratory of computational Science and Material Design Southern University of Science and Technology Shenzhen Key Laboratory of Quantum Science and Engineering International center for Quantum Materials School of PhysicsPeking University collaborative Innovation center of Quantum Matter cAS center for Excellence in Topological Quantum computation University of Chinese Academy of Sciences

The layer Hall effect describes electrons spontaneously deflected to opposite sides at different layers, which has been experimentally reported in the MnBi2Te4thin films under perpendicular electric fields. Here, we reveal a universal origin of the layer Hall effect in terms of the so-called hidden Berry curvature, as well as material design principles. Hence, it gives rise to zero Berry curvature in momentum space but non-zero layer-locked hidden Berry curvature in real space. We show that, compared to that of a trivial insulator, the layer Hall effect is significantly enhanced in antiferromagnetic topological insulators. Our universal picture provides a paradigm for revealing the hidden physics as a result of the interplay between the global and local symmetries, and can be generalized in various scenarios.

关键词： layerHall effect hidden Berry curvature antiferromagnetic insulator axion insulator, quantum transport

专业精神与行业竞争力:以香港为例谈如何确立风景园林行业之专业地位

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中国园林 2009年第1期25卷 10-14页

作者：陈弘志张安美国康奈尔大学香港大学建筑学院园境建筑学部香港园境师学会

自20世纪末以来,我国内地的风景园林行业正在经历着快速和深远的专业化变革。试图探讨在风景园林行业和风景园林教育的专业化进程中如何逐步确立行业的专业地位和专业精神,制订专业操守和行为准则,并保证专业教育中的课程设置和教学模... 详细信息

自20世纪末以来,我国内地的风景园林行业正在经历着快速和深远的专业化变革。试图探讨在风景园林行业和风景园林教育的专业化进程中如何逐步确立行业的专业地位和专业精神,制订专业操守和行为准则,并保证专业教育中的课程设置和教学模式既务实,又能实现风景园林学科在学术和知识体系上的进步。以香港为例,说明了行业竞争力和专业精神之间的关系,以及如何通过制订园境师专业操守、教学评估制度和园境师注册考试制度,加强行业规范,提升行业的国际竞争力。

关键词：风景园林专业精神专业教育竞争力

A refined representation method of the particle size distribution curve based on grading entropy

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Particuology 2024年第5期88卷 302-311页

作者： Xing Li Qun chen Zhaozhao Liu cheng Zhou chen Wang chen chen State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China

The particle size distribution(PSD)curve is an important expression of the basic properties of the soil.The characteristic parameters such as median particle size D 50,effective particle size D 10,and some combinations of characteristic parameters can only represent some points of the PSD curve,failing to represent all information of the PSD curve.In this paper,a fraction characteristic parameter F that could reflect the fraction size variation of the PSD curve was introduced based on grading entropy.And a new presentation method of the A-B-F three parameters was proposed for a refined representation of the PSD curve.It was found that the newly constructed model not only better represents the differences in the width of PSD curves but also has a higher sensitivity than the A-B two-parameter model proposed by Lőrincz.For PSD curves with similar distributions,the new presentation method has a higher degree of discrimination than that of the D 50-c u-c c three-parameter or the four-parameter combination G c proposed by Arshad.Finally,the application of this new method in describing the spatial nonuniformity distribution of depositions and predicting the soil hydraulic conductivity was discussed.The research results can provide a reference for the refined representation of PSD curves.

关键词： Grading entropy Particle size distribution curve Refined representation

Theoretical and experimental study of a bi-stable piezoelectric energy harvester under hybrid galloping and band-limited random excitations

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 461-478页

作者： Haitao LI Tianyu ZHENG Weiyang QIN Ruilan TIAN Hu DING J.c.JI Liqun chen Department of Engineering Mechanics North University of ChinaTaiyuan 030051China Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechnoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mechanical and Mechatronic Engineering University of Technology SydneyNew South Wales 2007Australia

In the practical environment,it is very common for the simultaneous occurrence of base excitation and crosswind.Scavenging the combined energy of vibration and wind with a single energy harvesting structure is fascinating.For this purpose,the effects of the wind speed and random excitation level are investigated with the stochastic averaging method(SAM)based on the energy envelope.The results of the analytical prediction are verified with the Monte-carlo method(McM).The numerical simulation shows that the introduction of wind can reduce the critical excitation level for triggering an inter-well jump and make a bi-stable energy harvester(BEH)realize the performance enhancement for a weak base excitation.However,as the strength of the wind increases to a particular level,the influence of the random base excitation on the dynamic responses is weakened,and the system exhibits a periodic galloping response.A comparison between a BEH and a linear energy harvester(LEH)indicates that the BEH demonstrates inferior performance for high-speed wind.Relevant experiments are conducted to investigate the validity of the theoretical prediction and numerical simulation.The experimental findings also show that strong random excitation is favorable for the BEH in the range of low wind speeds.However,as the speed of the incoming wind is up to a particular level,the disadvantage of the BEH becomes clear and evident.

关键词： bi-stability inter-well response galloping band-limited random

SP3111,A NOVEL SPERMATID-EXPRESSING PROTEIN INVOLVED IN SPERM-OOcYTE INTERAcTION

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SP3111,A NOVEL SPERMATID-EXPRESSING PROTEIN INVOLVED IN SPER...

Design of an on‑chip wavelength conversion device assisted by an erbium‑ytterbium co‑doped waveguide amplifier

The 5th Annual conference of the Asian Reproductive Biotechnology Society

作者： Michelle SANTOS ching-Ling c.chen Professional Postgraduate Services Knowledge Point 360 GroupLLC.SecaucusNJ 070942304. Professional Postgraduate Services Knowledge Point360 GroupLLC.SecaucusNJ 070942304.

＜正＞Successful sperm-oocyte interactions are necessary for fertilization.Each of these process is mediated by the sperm head,probably through proteins both on the sperm surface and within the acrosome.In this study,... 详细信息

关键词： testis sperm sperm-oocyte interaction in vitro fertilization

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Frontiers of Optoelectronics 2024年第2期17卷 51-60页

作者： chen Zhou Xiwen He Mingyue Xiao Deyue Ma Weibiao chen Zhiping Zhou School of Physical Sciences University of Science and Technology of ChinaHefei 230026China Aerospace Laser Technology and System Department Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Hangzhou Aijie Optoelectronic Technology co.Ltd. Hangzhou 311400China

In current documented studies,it has been observed that wavelength converters utilizing AlGaAsOI waveguides exhibit suboptimal on-chip wavelength conversion efficiency from the c-band to the 2μm band,generally falling below−20.0 dB.To address this issue,we present a novel wavelength conversion device assisted by a waveguide amplifier,incorporating both AlGaAs wavelength converter and erbium-ytterbium co-doped waveguide amplifier,thereby achieving a notable conversion efficiency exceeding 0 dB.The noteworthy enhancement in efficiency can be attributed to the specific dispersion design of the AlGaAs wavelength converter,which enables an upsurge in conversion efficiency to−15.54 dB under 100 mW of pump power.Furthermore,the integration of an erbium-ytterbium co-doped waveguide amplifier facilitates a loss compensation of over 15 dB.Avoiding the use of external optical amplifiers,this device enables efficient and high-bandwidth wavelength conversion,showing promising applications in various fields,such as optical communication,sensing,imaging,and beyond.

关键词： Silicon-based optoelectronics Wavelength conversion Waveguide amplifier 2μm band

controllable chemical redox reactions to couple microbial degradation for organic contaminated sites remediation:A review

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Journal of Environmental Sciences 2024年第5期139卷 428-445页

作者： Bin chen Jiang Xu Lizhong Zhu college of Environmental and Resource Sciences Zhejiang UniversityHangzhou 310058China Zhejiang Provincial Key Laboratory of Organic Pollution Process and control Zhejiang UniversityHangzhou 310058China Zhejiang Agriculture&Forest University Lin'an 311300China

Global environmental concern over organic contaminated sites has been progressively conspicuous during the process of urbanization and industrial restructuring.While traditional physical or chemical remediation technologies may significantly destroy the soil structure and function,coupling moderate chemical degradation with microbial remediation becomes a potential way for the green,economic,and efficient remediation of contaminated sites.Hence,this work systematically elucidates why and how to couple chemical technology with microbial remediation,mainly focused on the controllable redox reactions of organic contaminants.The rational design of materials structure,selective generation of reactive oxygen species,and estimation of degradation pathway are described for chemical oxidation.Meanwhile,current progress on efficient and selective reductions of organic contaminants(i.e.,dechlorination,defluorination,-NO_(2) reduction)is introduced.combined with the microbial remediation of contaminated sites,several consideration factors of how to couple chemical and microbial remediation are proposed based on both fundamental and practical points of view.This review will advance the understanding and development of chemical-microbial coupled remediation for organic contaminated sites.

关键词： Soil remediation Groundwater remediation Rational design Reactive species Environmental nanotechnology