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Distributed Cooperative Current-Sharing Control of Coupled Parallel Charging Systems with Super-Capacitor Loads 36

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Distributed Cooperative Current-Sharing Control of Coupled P...

Analysis of the Dynamic System of Wave Glider with a Towed Body

第36届中国控制会议

作者： Jiangang Liu Zhiqiang zheng School of Mathematics and Statistics Hunan University of Commerce School of Mechatronics Engineering and Automation National University of Defense Technology

ISBN: (纸本)9781538629185

In order to address the output current imbalanced problem of parallel chargers for energy storage type lignt rail vehicles,a distributed cooperative current-sharing scheme is proposed in this *** each charger as an agent,the current-sharing control design can be modeled as the output current consensus-tracking problem of nonlinear and non-identical multi-agent systems with the bounded control *** communication topology between each parallel charger is modeled a directed graph,which only needs a spanning *** order to guarantee the boundedness of the control input,a general saturation function is introduced into the control *** distributed cooperative PID current-sharing controller is designed based on the nearest neighborhood *** system stability and dynamic performance of the proposed cooperative control scheme is evaluated by analyzing the transfer function matrix from the input duty ratio to the output *** the physical parameters and communication topology of the parallel chargers are given in advance,the system stability can be maintained by choosing the proportional,integral and derivative control *** output current of parallel chargers can be balanced by adopting the proposed approach,which is verified by simulating a parallel charging test system.

关键词： Current-Sharing Control Parallel Chargers Multi-Agent Systems Cooperative PID Control

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Journal of Ocean University of China 2020年第3期19卷 519-524页

作者： ZHANG Jiakun CHANG Zongyu LU Guiqiao zheng Zhongqiang ZHANG Zhonglin College of Engineering Ocean University of ChinaQingdao 266100China Key Laboratory of Ocean Engineering of Shandong Province Qingdao 266100China College of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin 150001China

Mobile observation platforms are widely used in oceanographic and marine resource exploration and other applications. Wave Glider is a mobile platform that can transform wave energy into locomotion power and overcome the bottleneck of low energy supply. Wave Glider has recently been applied to tow underwater sensors fulfilling observation tasks. In this paper, the dynamic system of Wave Glider with a towed body is studied by applying multibody mechanics, and the relevant motion conditions of the system are investigated. Dynamic models of Wave Glider with a towed body and tether are first developed individually and then integrated into a whole model. The numerical method is used to obtain the dynamic responses and assess performance of the towed body pulled by the submerged glider of Wave Glider. The effects of sea state, mass of the towed body, and length of the towed cable are investigated on the basis of simulation results. This work can be used for the design and analysis of Wave Glider-towed body systems.

关键词： Wave Glider towed system motion response dynamic analysis

Multi-Topology Hierarchical Collaborative Hybrid Particle Swarm Optimization Algorithm for WSN

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China Communications 2023年第8期20卷 254-275页

作者： Yi Wang Kanqi Wang Maosheng Zhang Hongzhi zheng Hui Zhang School of Information Science&Technology Northwestern UniversityXi’an 710127China Institute of Artificial Intelligence Xiamen UniversityXiamen 361102China Institute of Disaster Prevention and Ecological Restoration Xi’an Jiaotong UniversityXi’an 710054China

Wireless sensor networks(WSN)are widely used in many situations,but the disordered and random deployment mode will waste a lot of sensor *** paper proposes a multi-topology hierarchical collaborative particle swarm optimization(MHCHPSO)to optimize sensor deployment location and improve the coverage of *** divides the population into three types topology:diversity topology for global exploration,fast convergence topology for local development,and collaboration topology for exploration and *** topologies are optimized in parallel to overcome the precocious convergence of *** paper compares with various heuristic algorithms at CEC 2013,CEC 2015,and CEC *** experimental results show that MHCHPSO outperforms the comparison *** addition,MHCHPSO is applied to the WSN localization optimization,and the experimental results confirm the optimization ability of MHCHPSO in practical engineering problems.

关键词： particle swarm optimizer levy flight multi-topology hierarchical collaborative framework lamarckian learning intuitive fuzzy entropy wireless sensor network

Systemic Governance of Mountains, Rivers, Forests, Farmlands, Lakes and Grasslands: Theoretical Framework and Approaches

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Chinese Journal of Urban and Environmental Studies 2021年第4期9卷 27-47页

作者： zheng Yan ZHUANG Guiyang University of Chinese Academy of Social Sciences Research Institute for Eco-Civilization Chinese Academy of Social Sciences

The life community of mountains, rivers, forests, farmlands, lakes and grasslands(MRFFLG) and its systemic governance are key components to build ecological civilization in China. It comprises diverse connotations in value, scientific and economic dimensions. Epistemologically, it comes from the Chinese traditional philosophy of harmonious coexistence of heaven, earth and man, and conforms to the Western ecological ethics, complex system science and environmental value theory. Methodologically, as a complex socio-ecological system in which man and nature interact and coexist, the life community of the MRFFLG should be governed coordinately from both narrow and broad views. At the policy level, from the perspectives of narrow synergy among ecological subsystems and broad synergy among the complex socio-ecological system, this paper evaluates the performance indicators of 16 pilot projects of the MRFFLG, and points out that the design of most pilot projects well reflects the narrow synergy of multiple ecological elements, but is short of attention to the broad synergy of green development and ecological civilization. There are two practical ways to promote the systemic governance of the MRFFLG. First, it needs to focus on the coordinated governance of watershed and ecological environment restoration against the background of global climate and environmental change. The goal is to restore and improve the service functions of ecological subsystems and enhance their climate adaptability. Second, in the context of new urbanization and green development transition, it requires a collaborative planning focusing on natural capital and green infrastructure investment, which is aimed at cultivating ecological dividends and realizing ecological economy.

关键词： Ecological civilization the life community of mountains, rivers, forests, farmlands, lakes and grasslands systemic governance complex socio-ecological system synergy

Surface water exchanges in the Luzon Strait as inferred from Lagrangian coherent structures

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Acta Oceanologica Sinica 2020年第11期39卷 21-32页

作者： Zhehao zheng Wei Zhuang Jianyu Hu Zelun Wu Changjian Liu State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361102China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China Joint Center for Ocean Remote Sensing University of Delaware-Xiamen UniversityNewarkDE 19716USA South China Sea Marine Survey and Technology Center Ministry of Natural ResourcesGuangzhou 510300China

This study presents a Lagrangian view of upper water exchanges across the Luzon Strait based on the finite-time Lyapunov exponents(FTLE)fields computed from the surface geostrophic *** Lagrangian coherent structures(LCSs)extracted from the FTLE fields well identify the typical flow patterns and eddy activities around the Luzon *** addition,they reveal the intricate transport paths and fluid domains,which are validated by the tracks of satellite-tracked surface drifters and cannot be visually recognized in the velocity *** FTLE fields indicate that there are mainly four types of transport patterns near the Luzon Strait;among them,the Kuroshio northward-flowing"leaping"pattern and the clockwise rotating"looping"pattern occur more frequently than the"leaking"pattern of the direct Kuroshio branch into the SCS and the"outflowing"pattern from the SCS to the *** eddy shedding events of the Kuroshio at the Luzon Strait are further analyzed,and the importance of considering LCSs in estimating transport by eddies is *** anticyclonic eddy(ACE)shedding cases reveal that ACEs mainly originate from the looping paths of Kuroshio and thus could effectively trap the Kuroshio water before eddy *** provide useful information to predict the positions of the upstream waters that finally enter the *** contrast,LCS snapshots indicate that during the formation of cyclonic eddies(CEs),most CEs are not connected with the pathways of Kuroshio ***,the contribution of CEs to the surface water exchanges from the Pacific into the SCS is tiny.

关键词： Lagrangian coherent structures(LCSs) Kuroshio Luzon Strait transport pathways particle tracking

Knowledge Graph-Driven Weather Overview Generation for the Beijing 2022 Winter Olympic Games

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Journal of Meteorological Research 2024年第5期38卷 983-998页

作者： Hanhua QU Jiangping zheng Wei TANG Muhua WANG Tianyue WANG China Meteorological Administration Public Meteorological Service Centre Beijing 100081

Weather Overview is regarded as one of the crucial meteorological services supporting the Beijing 2022 Olympic and Paralympic Winter Games(hereafter as Beijing 2022).As generation of Weather Overview involves multipledata,large-scale weather conditions,and vulnerability to weather changes,there still exist quite some challenges in obtaining Weather *** present,knowledge graph(KG)is believed to be an effective way to describe information and ***,this study focuses on development of a framework to automatically generate Weather Overview using *** first present a three-layer KG model to generate accurate content of Weather Overview:(1)knowledge acquisition of entities and relationships to construct the specific corpora;(2)knowledge representation of the relationships between weather conditions and the events based on ontology;and(3)knowledge application of corpora,variables,and weather conditions to query and reason knowledge with ***,an XML Schema is used to achieve the standardized Weather Overview,which is formed by sentence-paragraph-text *** model is validated for a typical case at the Yanqing National Alpine Skiing Centre in Beijing *** to the manual method,the accuracy and standardization of Weather Overview can be maintained above 90%,and it can be automatically generated within *** method proposed in this study provides a helpful meteorological service solution to other large-scale sports events.

关键词： Weather Overview automatic generation knowledge graph(KG) XML Schema the Beijing 2022 Winter Olympic Games

Syn-mineralization Uplifting and Exhumation of Porphyry Systems in China:Evidence from Fluid Inclusion Data

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Acta Geologica Sinica(English Edition) 2022年第1期96卷 240-247页

作者： ZHOU Aorigele zheng Ming TANG Juxing HE Wen CHEN Hongjin MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China

In order to understand how the metallogenic process of porphyry deposit specifically and directly respond to regional uplifting and exhumation,we compiled previous fluid inclusion data of 32 porphyry deposits in China by recalculating the fluid trapping depths and trapping depth reduction magnitude from early to late mineralization stage *** data reveal that the average trapping pressure ratio(Ave TP_(E)/TP_(L))between early-and late-stage veins of the these deposits are 1.2-18.4,mainly in the range of 1.35-5.83,with average trapping pressure reduction(1-Ave TP_(L)/TP_(E))from early-to late-stage veins are 17%-95%,and mainly in the range of 25%-83%.The fluid trapping pressure based mineralization depths most of the porphyry deposits in China had decreased from early to late vein stages by at least 450 m(900-5800 m predominant),or greater than 950 m when take the average depth reduction value,which is greater than the current gap between early-and late-stage veins of each *** propose that the apparently greater mineralization depth reduction magnitude than the current elevation gaps between early and late veins are likely a consequence of synmineralization uplifting and exhumation process that often occurs in porphyry systems.

关键词： fluid inclusion syn-mineralization uplifting exhumation porphyry deposit

Spatial distributions of sunspot oscillation modes at different temperatures

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Research in Astronomy and Astrophysics 2020年第1期20卷 43-48页

作者： zheng-Kai Wang Song Feng Lin-Hua Deng Yao Meng Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500China Yunnan Observatories Chinese Academy of SciencesKunming 650216China College of Science China Three Gorges UniversityYichang 443002China Chongqing University of Arts and Sciences Chongqing 402160China

Three-and five-minute sunspot oscillations have different spatial distributions in the solar atmospheric *** spatial distributions are crucial for revealing the physical origin of sunspot oscillations and to investigate their *** this study,six sunspots observed by Solar Dynamics Observatory/Atmospheric Imaging Assembly were used to obtain the spatial distributions of three-and five-minute *** fast Fourier transform method is applied to represent the power spectra of oscillation *** find that,from the temperature minimum to the lower corona,the powers of the fiveminute oscillation exhibit a circle-shape distribution around its umbra,and the shapes gradually expand with temperature ***,the circle-shape disappears and the powers of the oscillations appear to be very disordered in the higher *** indicates that the five-minute oscillation can be suppressed in the high-temperature *** the three-minute oscillations,from the temperature minimum to the high corona,their powers mostly distribute within an umbra,and part of them are located at the coronal fan loop ***,those relative higher powers are mostly concentrated in the position of coronal loop footpoints.

关键词： Sun:atmosphere Sun:sunspots Sun:oscillations

Stability analysis of robotic longitudinal-torsional composite ultrasonic milling

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Chinese Journal of Aeronautics 2022年第8期35卷 249-264页

作者： Lianjun SUN Wenhe LIAO Kan zheng Wei TIAN Jinshan LIU Jindan FENG School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China China Academy of Space Technology Beijing 100094China

Currently,industrial robots are considered as an alternative towards traditional machine *** for the large-scale parts milling,robotic flexibility and low cost make it possess the ***,the milling chatter caused by its weak rigidity hampers robotic application and promotion severely in aviation *** ultrasonic milling(RUM)technology with one-dimensional axial vibration has been proven and approved on avoiding robotic *** on this,the research of project team demonstrates that longitudinal-torsional composite ultrasonic milling(CUM-LT)involving separation characteristic has a greater advantage than RUM in terms of chatter ***,the CUM-LT as a new means is applied to avoid processing vibration of robotic milling *** its influence mechanism on stability improvement of weak stiffness processing system is ***,the approaches to strengthen separation effect are provided ***,a new analysis method of robotic CUM-LT(RCUM-LT)stability is proposed on the basis of ultrasonic function *** simulation and experimental results indicate that compared with robotic RUM(RRUM),stability regions of separated RCUM-LT(SRCUM-LT)and unseparated RCUM-LT(URCUM-LT)are improved by 124.42%and39.20%,*** addition of torsional ultrasonic energy has a wonderful effect on the milling chatter suppression of low stiffness robots.

关键词： Chatter suppression Industrial robots Longitudinal-torsional composite Rotary ultrasonic milling Stability analysis