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Progress in models for coupled human and natural systems

Science China Earth Sciences 2024年第11期67卷 3631-3637页

作者： Tianxiang YUE Chenchen WU Wenjiao SHI Yongzhong TIAN Qing WANG Yimin LU Lili ZHANG State Key Laboratory of Resources and Environment Information System Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China School of Geographical Sciences Southwest UniversityChongqing 400715China National Institute of Environmental Health Chinese Center for Disease Control and PreventionBeijing 100021China National Engineering Research Center of Geospatial Information Technology Fuzhou UniversityFuzhou 350108China The Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China

1. Introduction Malthus (1798) was one of the earliest researchers to propose a coupled human-natural system (CHANS) model, particularly in his analysis of the relationship between population growth and food supply. He argued that while population grows geometrically, food supply increases only arithmetically, suggesting that this imbalance could eventually lead to a food crisis due to diminishing per capita food availability (Malthus, 1798).

关键词： Malthus eventually population

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Characteristics of low-speed streaks and vortex structures in drag-reduced turbulent channel flow investigated by stereoscopic PIV

Characteristics of low-speed streaks and vortex structures i...

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2004 ASME International Mechanical engineering Congress and Exposition, IMECE 2004

作者： Li, Feng-Chen Segawa, Takehiko Kawaguchi, Yasuo Hishida, Koichi Turbomachinery Research Group Institute for Energy Utilization National Institute of Advanced Industrial Science and Technology Tsukuba 305-8564 Japan Center for Smart Control of Turbulence Department of System Design Engineering Keio University Yokohama 223-8522 Japan

In the present study, we employed stereoscopic particle image velocimetry (SPIV) to investigate the characteristics of turbulence structures in a drag-reduced turbulent channel flow with addition of surfactant. The tested drag-reducing fluid was a CTAC (cetyltrimethyl ammonium chloride)/NaSal/Water system maintained at 25°C, having a 30-ppm concentration of CTAC. SPIV measurement was performed for a water flow (Re = 1.1×105) and a CTAC solution flow (Re = 1.5×105 with 54% drag reduction) in both the streamwise-spanwise and wall-normal-spanwise planes, respectively. A series of wall-normal vortex cores were found to align with the low-speed streaks with opposite vorticity signals at both sides of the streaks and with the vorticity decreased averagely by about one order in CTAC solution flow compared with water flow;the spanwise spacing between the low-speed streaks in the solution flow is increased by about 42%. The streamwise vorticity of the vortex cores appearing in the wall-normal-spanwise plane was also decreased by the use of additives. Copyright © 2004 by ASME.

关键词： Channel flow

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A Tabu search approach for optimizing server placement in distributed systems

A Tabu search approach for optimizing server placement in di...

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2nd International Conference on Networking and Distributed Computing, ICNDC 2011

作者： Wang, Biyao Wang, Jinlin Liu, Xue Key Lab. of Network Communication System and Control University of Science and Technology of China Chinese Academy of Sciences Hefei China National Network New Media Engineering Research Center Institute of Acoustics Chinese Academy of Sciences Beijing China

ISBN: (纸本)9780769544274

In distributed systems, the server placement problem in which a new server has to compete with existing servers for user requests is important in planning of constructing new business service sites. In addition to minimizing cost, competition-aware server placement also needs to maximize the benefit of building a new server. This paper proposes a Tabu Search approach to optimize the problem in general graphs. Results from the simulation experiments show that it do has a better performance than both of the GreedyAdd and GreedyRemove algorithms. © 2011 IEEE.

关键词： Tabu search

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An online defect classification method for float glass fabrication

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Glass technology: European Journal of Glass Science and technology Part A 2011年第5期52卷 154-160页

作者： Peng, Xiangqian Chen, Youping Liu, Huaiguang Xie, Jingming Gu, Chenlin Engineering Research Center of Numerical Control System School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China College of Mechanical and Electrical Engineering Central South University Changsha Hunan China

In float glass fabrication once defects are detected, recognition of the defect type is important for adjustment of the process conditions. Based on analysis of the float process conditions and float glass defects, this paper outlines an adaptive neural network based classification. Twelve features of the defect are picked out as the inputs for defect classification. The ReliefF method is used to evaluate the features, and the sequence of defect features is decided based on the results of the evaluation. The momentum term and adaptive learning rate is used to address the classification's disadvantage of slow learning speed and easy falling into a local minimum. Experiments and real application proves that the float glass defect classification presented here correctly recognizes defects in real time, and satisfies the requirements of float glass fabrication.

关键词： Defects

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Dynamic Event-Triggered Consensus on Matrix-Weighted Networks: Leadless Case 42

Dynamic Event-Triggered Consensus on Matrix-Weighted Network...

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42nd Chinese control Conference, CCC 2023

作者： Dou, Lintao Wei, Haoyu Huang, Jian Pan, Lulu Shao, Haibin Li, Dewei College of Intelligent Science National University of Defense Technology Changsha410003 China Shanghai Jiao Tong University Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai Engineering Research Center of Intelligent Control and Management Department of Automation Shanghai200240 China

ISBN: (纸本)9789887581543

This paper examines the event-triggered consensus of the multi-agent system on matrix-weighted networks, where the interdependencies among higher-dimensional states of neighboring agents are characterized by matrix-weighted edges in the network. Specifically, a novel distributed dynamic event-triggered coordination strategy is proposed for this category of generalized networks, in which an auxiliary system is employed for each agent to dynamically adjust the triggering threshold, which plays an essential role in guaranteeing that the triggering time sequence does not exhibit Zeno behavior. Distributed event-triggered control protocols are proposed to guarantee leaderless consensus for multi-agent systems on matrix-weighted networks, respectively. Remarkably, the spectrum of matrix-valued weights is crucial in event-triggered mechanism design for matrix-weighted networks, generalizing those results only applicable for scalar-weighted networks. The proposed approach allows each agent to broadcast and receive information only at its triggering instants. Finally, simulation examples are provided to demonstrate the theoretical results. © 2023 Technical Committee on control Theory, Chinese Association of Automation.

关键词： Multi agent systems

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Development of a PLCopen-Based controller for Flexible Fatigue Test Applications

Development of a PLCopen-Based Controller for Flexible Fatig...

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International Conference on Mechatronics and Machine Vision in Practice (M2VIP)

作者： Xiaofan Lyu Pingjiang Wang Chaoyang Gao Donglin Zhao Peng Wei Wenbin Luo School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan China National Numerical Control System Engineering Research Center Huazhong University of Science and Technology Wuhan China Quanzhou HUST Research Institute of Intelligent Manufacturing QuanZhou China

ISBN: (数字)9798350391916

ISBN: (纸本)9798350391923

Aiming at the flexibility and reconfigurability needs for fatigue test applications, the demand for a PLCopen-based development framework arises. In this study, we utilize the IEC 61131-3 programmable language and PLCopen specifications to design the controller for electro-hydraulic servo loading system. Firstly, PLCopen group function block diagrams are proposed in accordance with experiments. Multiple groups can manage different experiments simultaneously. Then, PLCopen channel function block diagrams are designed to manage district channels in a group. To correct tracking errors, each channel incorporates a peak-valley phase compensator. Peak-valley phase compensator could potentially be used to adjust for multi-frequency sinusoidal spectrum. Finally, simulation and experiment results verify that tracking error could be kept within a defined neighbourhood region.

关键词： Mechatronics Machine vision Loading Fatigue IEC Standards Servomotors

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Automatic sleep stage classification GUI with a portable EEG device

Automatic sleep stage classification GUI with a portable EEG...

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15th International Conference on Human-Computer Interaction, HCI International 2013

作者： Huang, Chih-Sheng Lin, Chun-Ling Ko, Li-Wei Wang, Yu-Kai Liang, Jyun-Wei Lin, Chin-Teng Brain Research Center University System of Taiwan Hsinchu Taiwan Institute of Electrical Control Engineering National Chiao-Tung University Hsinchu Taiwan Department of Biological Science and Technology National Chiao-Tung University Hsinchu Taiwan Department of Computer Science National Chiao-Tung University Hsinchu Taiwan

ISBN: (纸本)9783642394720

In this study, a developed automatic sleep stage classification system with a portable EEG recording device, (Mindo-4s) is implemented by JAVA-based sleep graphical user interface (GUI) in android platform. First, the parameters of the developed sleep stage classification system, including extracting effective sleep features and a hierarchical classification structure consisting of preliminary wake detection rule, adaptive adjustment scheme, and support vector machine, were trained by our existing sleep database, which collected using polysomnogram (PSG), in MATLAB program. Finally, this classification system would be reedited by JAVA language, and the corresponding JAVA-based sleep GUI software was working in android platform and Mindo-4s. The connection between JAVA-based sleep GUI software and the portable Mindo-4s was through Bluetooth communication. The performance of this JAVA-based sleep GUI can reach 72.43% average accuracy comparing to the result from manual scoring. This JAVA-based sleep GUI can on-line display, record and analyze the forehead EEG signals simultaneously. After sleep, the user can received a complete sleep report, including sleep efficiency, sleep stage distribution, from JAVA-based sleep GUI. Thus, this system can provide a preliminary result in sleep quality estimation, and help the sleep doctor to decide someone needs to have a complete PSG testing in hospital. Using this system is more convenient for long-term and home-based daily caring than traditional PSG measurement. © Springer-Verlag Berlin Heidelberg 2013.

关键词： Graphical user interfaces

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Influence of drag-reducing surfactant additives on vortex structures and turbulent events in a channel flow

Influence of drag-reducing surfactant additives on vortex st...

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Proceedings of the ASME Heat Transfer/Fluids engineering Summer Conference 2004, HT/FED 2004

作者： Li, Feng-Chen Segawa, Takehiko Kawaguchi, Yasuo Hishida, Koichi Turbomachinery Research Group Institute for Energy Utilization National Institute of Advanced Industrial Science and Technology Tsukuba 305-8564 Japan Center for Smart Control of Turbulence Japan Department of System Design Engineering Keio University Yokohama 223-8522 Japan

The characteristics of vortex structures and turbulent events of drag-reducing surfactant (CTAC) solution flows in a two-dimensional channel have been studied using particle image velocimetry (PIV) to measure the instantaneous velocity fields in a streamwise-wall-normal plane. Through visualizing the instantaneous velocity field, contour maps of the swirling strength and instantaneous value of uv, the characteristic angle of vortex packets was quantified, and it was shown that the drag-reducing CTAC additive reduced both the strength and frequency of turbulent bursts near the wall, and that the characteristics of vortex structures and bursts were not only dependent on drag-reduction level but also on concentration of additive. Based on the quantified parameters characterizing turbulent events in a wall-bounded turbulent flow, a model of turbulent contribution to the friction factor, f T, was proposed. It was obtained that fT was linearly proportional to the product of frequency and strength of turbulent events. Copyright © 2004 by ASME.

关键词： Additives

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Printed circuit board inspection system PI/1 2

Printed circuit board inspection system PI/1

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Automated Inspection and High-Speed Vision Architectures II 1988

作者： Yu, Shiaw-Shian Cheng, Wen-Chin Chiang, Chris S. C. Advanced Technology Center Electronics Research and Service Organization Industrial Technology Research Institute Chutung Hsinchu31015 Taiwan Control System Department Electronics Research and Service Organization Industrial Technology Research Institute Chutung Hsinchu31015 Taiwan Institute of Computer Science and Information Engineering National Chiao Tung University Hsinchu30049 Taiwan AITech International Corporation United States

An automatic printed circuit board (PCB) inspection system called PI/l, is described in this paper. The system can inspect PCB artwork and inner layers to find trace faults such as open circuits, short circuits, pin holes, fine lines and narrow line spaces. PI/1 uses a line scan camera with 1024 pixels resolution to take images. The whole image can be obtained by the help of a scanning mechanism in the X and the Y directions. Continuous pictures can be taken without blurring, and the resolution is between 1/2 to 2 mils. The inspection method used in PI/1 is a type of design rule checking. It does not require a reference image and can tolerate changes in the inspection environment due to illumination and PCB positioning. The inspection algorithm has been implemented into a special hardware and the inspection speed is about 4 x 106 pixels/sec. © 1989 SPIE. All rights reserved.

关键词： Printed circuit boards

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Dissecting the contributions of organic nitrogen aerosols to global atmospheric nitrogen deposition and implications for ecosystems

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national Science Review 2023年第12期10卷 124-136页

作者： Yumin Li Tzung-May Fu Jian Zhen Yu Xu Yu Qi Chen Ruqian Miao Yang Zhou Aoxing Zhang Jianhuai Ye Xin Yang Shu Tao Hongbin Liu Weiqi Yao Shenzhen Key Laboratory of Precision Measurement and Early Warning Technology for Urban Environmental Health Risks School of Environmental Science and Engineering Southern University of Science and Technology Guangdong Provincial Observation and Research Station for Coastal Atmosphere and Climate of the Greater Bay Area Southern University of Science and Technology Division of Environment and Sustainability Hong Kong University of Science and Technology National Center for Applied Mathematics Shenzhen Department of Chemistry Hong Kong University of Science and Technology State Key Joint Laboratory of Environmental Simulation and Pollution Control International Joint Laboratory for Regional Pollution Control College of Environmental Sciences and Engineering Peking University Frontier Science Center for Deep Ocean Multispheres and Earth System and Physical Oceanography Laboratory Ocean University of China College of Oceanic and Atmospheric Sciences Ocean University of China Department of Ocean Science Hong Kong University of Science and Technology Department of Ocean Science and Engineering Southern University of Science and Technology

Atmospheric deposition of particulate organic nitrogen（ONp） is a significant process in the global nitrogen cycle and may be pivotally important for N-limited ***,past models largely overlo oked the spatial and chemical inhomogeneity of atmospheric ONpand were thus deficient in assessing global *** constructed a comprehensive global model of atmospheric gaseous and particulate organic nitrogen（ON）,including the latest knowledge on emissions and secondary *** this model,we simulated global atmospheric ONpabundances consistent with *** estimated global atmospheric ON deposition was 26 Tg N yr-1,predominantly in the form of ONp(23 Tg N yr-1)and mostly from wildfires（37%）,oceans（22%） and aqueous productions（17%）.Globally,ONpcontributed as much as 40% to 80% of the total N deposition downwind of biomass-burning *** ONpdeposition thus constituted the dominant external N supply to the N-limited boreal forests,tundras and the Arctic Ocean,and its importance maybe amplified in a future warming climate.

关键词： organic nitrogen aerosol secondary organic nitrogen biomass burning

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