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二级构筑水平上刺五加种群分布格局的研究

吉林林学院学报 1993年第1期9卷 34-39页

作者：臧润国邓守彦樊后保吉林林学院科研处吉林省林业勘察设计院福建林学院林学系

本文研究了刺五加无性系群团在群落中以及无性系小株在无性系内的分布格局,运用聚集强度指数分析了刺五加无性系种群在不同群落中的聚集性程度。

关键词：刺五加种群分布格局聚集强度指数组元构件

Adaptive Control of a Flexible Manipulator With Unknown Hysteresis and Intermittent Actuator Faults

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 148-158页

作者： shouyan Chen Weitian He Zhijia Zhao Yun Feng Zhijie Liu Keum-Shik Hong School of Mechanical and Electrical Engineering Guangzhou University the School of Control Science and Engineering Shandong University IEEE the College of Electrical and Information Engineering Hunan University the National Engineering Research Center for Robot Visual Perception and Control Technology Hunan University the School of Intelligence Science and Technology University of Science and Technology Beijing (USTB) the Institute for Future the School of AutomationQingdao University the School of Mechanical Engineering Pusan National University

In this study, we consider a single-link flexible manipulator in the presence of an unknown Bouc-Wen type of hysteresis and intermittent actuator faults. First, an inverse hysteresis dynamics model is introduced, and then the control input is divided into an expected input and an error compensator. Second,a novel adaptive neural network-based control scheme is proposed to cancel the unknown input hysteresis. Subsequently,by modifying the adaptive laws and local control laws, a fault-tolerant control strategy is applied to address uncertain intermittent actuator faults in a flexible manipulator system. Through the direct Lyapunov theory, the proposed scheme allows the state errors to asymptotically converge to a specified interval. Finally,the effectiveness of the proposed scheme is verified through numerical simulations and experiments.

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Upgrade of the sextupole field for beam instability mitigation in rapid cycling synchrotron of China Spallation Neutron Source

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Radiation Detection Technology and Methods 2023年第4期7卷 550-560页

作者： Liangsheng Huang Yuwen An Changdong deng Yuan Huang shouyan Xu Dongguan Campus Institute of High Energy PhysicsChinese Academy of Sciences(CAS)Dongguan523803China Spallation Neutron Source Science Center Dongguan523803China Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China

Background The China Spallation Neutron Source incorporates a rapid cycling synchrotron(RCS)that operates by accumulating protons at 80 MeV and subsequently accelerating them to 1.6 GeV within a time span of 20 *** beam is guided to striking the tungsten target for neutron *** As a space charge dominated machine,the RCS is subject to space charge effects and momentum spread,hereby influencing the tune *** address this issue,sextupole magnets,powered by two families of DC power supply,were initially employed to decrease the absolute value of chromaticity and to control the tune *** head-tail instability has been observed during the RCS beam *** The beam tests and simulations were conducted,revealing that tuning the chromaticity proved to be an effective mitigation ***,to achieve better control over the tune spread and further suppress the instability,the DC sextupole field has been upgraded to an AC sextupole field,aiming to provide dynamic for controlling the chromaticity over an acceleration *** and conclusion Thanks to the upgraded of AC field,the instability has been fully mitigated with beam power of 100 kW and the transmission in the RCS has been improved by~2%from 96 to 98%.With help of AC sextupole at present,the beam power in the RCS is increased to 140 kW.

关键词： China spallation neutron source Rapid cycling synchrotron Sextupole field Chromaticity Head-tail instability

DELAY-DEPENDENT STABILITY OF LINEAR MULTISTEP METHODS FOR NEUTRAL SYSTEMS WITH DISTRIBUTED DELAYS

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Journal of Computational Mathematics 2022年第3期40卷 484-498页

作者： Yuhao Cong shouyan Wu Shanghai Customs College Shanghai 201204China Department of Mathematics Zhejiang International Studies UniversityHangzhou 310023China Department of Mathematics Shanghai Normal UniversityShanghai 200234China

This paper considers the asymptotic stability of linear multistep(LM)methods for neutral systems with distributed *** particular,several sufficient conditions for delay-dependent stability of numerical solutions are obtained based on the argument *** quadrature formulae are used to compute the *** algorithm is proposed to examine the delay-dependent stability of numerical *** numerical examples are performed to verify the theoretical results.

关键词： Neutral systems with distributed delays Linear multistep methods Delaydependent stability Argument principle

In vivo optical bioimaging by using Nd-doped LaF3 luminescent nanorods in the second near-infrared window

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Journal of Rare Earths 2019年第9期37卷 931-936,I0002页

作者： shouyan Cheng Liu Liu Qiuhua Yang Youbin Li Songjun Zeng Synergetic Innovation Center for Quantum Effects and Application Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of EducationSchool of Physics and ElectronicsHunan Normal University

Fluorescent imaging in the second near-infrared(NIR-Ⅱ,1000-1700 nm)region has attracted enormous research interest due to its advantages of unprecedentedly improved imaging sensitivity and spatial ***,high quality NIR-Ⅱemissive LaF3:Nd3+nanorods(NRs)with hexagonal phase structure and controlled size were synthesized by a hydrothermal *** the Nd^3+doping induced NIRⅡluminescent intensity evolution was studied,In vivo NIR-Ⅱbioimaging and real-time tracking reveal that these LaF3:Nd^3+NRs are mainly accumulated in liver and ***,in vivo toxicity assessment demonstrates that LaF3:Nd^3+NRs feature low biotoxicity and good biocompatibility in living ***,the NIR-Ⅱemitting hexagonal phase LaF3 NRs with controlled size are promising probes for optical bioimaging.

关键词： NIR-Ⅱimaging Real-time tracking Downshifting luminescence Rare earths

A review of persulfate-based advanced oxidation system for decontaminating organic wastewater via non-radical regime

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Frontiers of Environmental Science & Engineering 2024年第11期18卷 39-52页

作者： Yunxin Huang shouyan Zhao Keyu Chen Baocheng Huang Rencun Jin School of Life and Environmental Sciences Hangzhou Normal UniversityHangzhou 310018China School of Engineering Hangzhou Normal UniversityHangzhou 310018China

The large amount of refractory organic wastewater produced from industry and agriculture sectors poses a significant threat to both water ecosystems and human health,necessitating the exploration of cost-efficient and efficacious removal ***,when activated by various catalysts,can produce oxidative species,demonstrating promising potential in remediating organic *** recent years,numerous studies have unveiled that persulfate can be readily decomposed into nonradicals,which exhibits high selectivity toward pollutants and robust performance in complex wastewater ***,the challenges in identifying non-radicals and the unclear catalytic mechanism hinder its further *** paper critically reviews the research progress on non-radical oxidation in persulfate-based heterogeneous catalytic *** main advancements and existing challenges in three non-radical oxidation pathways,i.e.,singlet oxygen,electron transfer,and high-valent metal oxides,are summarized,and the key factors influencing the production of nonradicals are *** engineering aspects of non-radical oxidation system are further discussed,and the future prospects of this technology in wastewater treatment are *** review aims to bridge the knowledge gaps between current research and future requirements.

关键词： Non-radicals Heterogeneous Peroxymonosulfate Peroxydisulfate Wastewater treatment Engineering application

Neural-Network-Based Adaptive Finite-Time Control for a Two-Degree-of-Freedom Helicopter System With an Event-Triggering Mechanism

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IEEE/CAA Journal of Automatica Sinica 2023年第8期10卷 1754-1765页

作者： Zhijia Zhao Jian Zhang shouyan Chen Wei He Keum-Shik Hong IEEE the School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhou 510006China the School of Intelligence Science and Technology the Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China the School of Mechanical Engineering Pusan National UniversityBusan 46241South Korea the Institute for Future School of AutomationQingdao UniversityQingdao 266071China

Helicopter systems present numerous benefits over fixed-wing aircraft in several fields of *** control schemes for improving the tracking accuracy of such systems is *** paper proposes a neural-network(NN)-based adaptive finite-time control for a two-degree-of-freedom helicopter *** particular,a radial basis function NN is adopted to solve uncertainty in the helicopter ***,an event-triggering mechanism(ETM)with a switching threshold is proposed to alleviate the communication burden on the *** proposing an adaptive parameter,a bounded estimation,and a smooth function approach,the effect of network measurement errors is effectively compensated for while simultaneously avoiding the Zeno ***,the developed adaptive finite-time control technique based on an NN guarantees finitetime convergence of the tracking error,thus enhancing the control accuracy of the *** addition,the Lyapunov direct method demonstrates that the closed-loop system is semiglobally finite-time ***,simulation and experimental results show the effectiveness of the control strategy.

关键词： Adaptive neural-network control event-triggering mechanism(ETM) finite time two-degree-of-freedom helicopter

Evaluation of 1,4-naphthoquinone derivatives as antibacterial agents:activity and mechanistic studies

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Frontiers of Environmental Science & Engineering 2023年第3期17卷 49-61页

作者： Zhizhuo Liu Zhemin Shen shouyan Xiang Yang sun Jiahua Cui Jinping Jia School of Environmental Science&Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The diverse and large-scale application of disinfectants posed potential health risks and caused ecological damage during the 2019-nCoV pandemic,thereby increasing the demands for the development of disinfectants based on natural products,with low health risks and low aquatic *** the present study,a few natural naphthoquinones and their derivatives bearing the 1,4-naphthoquinone skeleton were synthesized,and their antibacterial activity against selected bacterial strains was *** vitro antibacterial activities of the compounds were investigated against Escherichia coli and Staphylococcus *** the minimum inhibitory concentration(MIC)of≤0.125μmol/L for juglone(1a),5,8-dimethoxy-1,4-naphthoquinone(1f),and 7-methyl-5-acetoxy-1,4-naphthoquinone(3),a strong antibacterial activity against *** was *** 1,4-naphthoquinone derivatives exhibited a strong antibacterial activity,with MIC values ranging between 15.625 and 500μmol/Land ECso values rangingbetween10.56 and248.42μmol/*** of the synthesized compounds exhibited strong antibacterial activities against *** these compounds,juglone(la)showed the strongest antibacterial *** results from mechanistic investigations indicated that juglone,a natural naphthoquinone,caused cell death by inducing reactive oxygen species production in bacterial cells,leading to DNA *** addition,juglone could reduce the self-repair ability of bacterial DNA by inhibiting RecA *** addition to having a potent antibacterial activity,juglone exhibited low cytotoxicity in cell-based *** conclusion,juglone is a strong antibacterial agent with low toxicity,indicating that its application as a bactericidal agent may be associated with low health risks and aquatic toxicity.

关键词： 1,4-naphthoquinone derivatives Antibacterial Actionmechanism RecA

Residual orbit of BC bump for CSNS/RCS

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Radiation Detection Technology and Methods 2019年第3期3卷 262-267页

作者： Ming-Yang Huang Sheng Wang shouyan Xu Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Dongguan Institute of Neutron Science Dongguan 523808China

Background In a beam cycle,there is a chicane bump(BC bump)in the injection region of the China Spallation Neutron Source(CSNS).It is a core part of the injection system and the important guarantee that the Linac beam injecting into the rapid cycling synchrotron(RCS).During the beam commissioning,the residual orbit of BC bump,i.e.,the closed-orbit distortion(COD)due to the imperfect BC bump,was an important problem which can affect the orbit correction and beam loss control of the *** The purpose is to develop a suitable method to judge and correct the residual orbit of BC *** According to the physics design,there is no residual orbit of BC bump in ***,if the residual orbit of BC bump exists in the actual operation,the circular beam orbit outside the injection region would be *** comparing the circular beam orbit outside the BC bump region in theory and that is measured in the actual operation,whether the residual orbit of BC bump exists can be *** using the three auxiliary windings of BC magnets,the residual orbit of BC bump can be *** The numerical simulation results showed that the measurement and correction methods had worked well and they can be applied to the beam commissioning of CSNS/*** measurement results in the machine study showed that the residual orbit of BC bump is not large and can be reduced by the three auxiliary windings of BC *** The methods to judge and correct the residual orbit of BC bump worked well and had been applied to the beam commissioning of CSNS/RCS.

关键词： CSNS Injection system BC bump Residual orbit