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arXiv 2019年

作者： Ren, Hai-Peng Zhou, Zi-Xuan Grebogi, Celso Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi’an University of Technology Xi’anShaanxi710048 China North Minzu University Library Yinchuan Ningxia750021 China Institute for Complex System and Mathematical Biology University of Aberdeen AB24 3UE United Kingdom

Silicon crystal puller (SCP) is a key equipment in silicon wafer manufacture, which is, in turn, the base material for the most currently used integrated circuit (IC) chips. With the development of the techniques, the demand for longer mono-silicon crystal rod with larger diameter is continuously increasing in order to reduce the manufacture time and the price of the wafer. This demand calls for larger SCP with increasing height, however, it causes serious swing phenomenon of the crystal seed. The strong swing of the seed causes difficulty in the solidification and increases the risk of mono-silicon growth *** main aim of this paper is to analyze the nonlinear dynamics in the FSRL system of the SCP. A mathematical model for the swing motion of the FSRL system is derived. The influence of relevant parameters, such as system damping, excitation amplitude and rotation speed, on the stability and the responses of the system are analyzed. The stability of the equilibrium, bifurcation and chaotic motion are demonstrated, which are often observed in practical situations. Melnikov method is used to derive the possible parameter region that leads to chaotic motion. Three routes to chaos are identified in the FSRL system, including period doubling, symmetry-breaking bifurcation and interior crisis. The work in this paper explains the complex dynamics in the FSRL system of the SCP, which will be helpful for the SCP designers in order to avoid the swing phenomenon in the SCP. Copyright © 2019, The Authors. All rights reserved.

关键词： Silicon wafers

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Assessment and prediction of leakage degree of expansion joints in underground network heating pipe network based on LS-SVM and ARIMA model 13

Assessment and prediction of leakage degree of expansion joi...

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13th IEEE Conference on Industrial Electronics and Applications, ICIEA 2018

作者： Shang-Bin, Jiao Le, Fan Peng-Yue, Wu Lei, Qiao Yong-Ze, Jin Qian-Kun, Shen Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi'an University of Technology Xi'an710048 China Xi'an Thermal Power Research Institute Co. Ltd Xi'an710054 China

ISBN: (纸本)9781538637579

The study shows that the leakage of the expansion joints in the underground heating primary pipe network will lead to the fluctuation of soil temperature and conductivity around the leakage point. Based on the online monitoring of changes of physical quantities around the expansion joint, this paper established the assessment model of temperature and conductivity as the input parameters and the degree of expansion joints leakage as the output parameters, which took the radial basis function as kernel function and made use of PSO algorithm to achieve the optimization of the kernel function parameters. Then, the temperature and conductivity were predicted based on the ARIMA model, and the LS-SVM assessment of expansion joint leakage was realized according to the prediction results. Both simulation and field experiments show that the prediction model based on ARIMA has higher accuracy, which has identified the foundation for on-line prediction and accurate assessment of the expansion joint leakage in the underground heating primary pipe network. © 2018 IEEE.

关键词： Particle swarm optimization (PSO)

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Multiple residual dense networks for reconfigurable intelligent surfaces cascaded channel estimation

arXiv

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arXiv 2021年

作者： Jin, Yu Zhang, Jiayi Huang, Chongwen Yang, Liang Xiao, Huahua Ai, Bo Wang, Zhiqin The School of Electronic and Information Engineering Beijing Jiaotong University Beijing100044 China The Frontiers Science Center for Smart High-speed Railway System Beijing Jiaotong University Beijing100044 China Zhejiang Provincial Key Lab of Information Processing Communication and Networking Zhejiang University Hangzhou310007 China College of Computer Science and Electronic Engineering Hunan University Changsha410082 China ZTE Corporation State Key Laboratory of Mobile Network Mobile Multimedia Technology Shenzhen518057 China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing100044 China Henan Joint International Research Laboratory of Intelligent Networking and Data Analysis Zhengzhou University Zhengzhou450001 China Research Center of Networks and Communications Peng Cheng Laboratory Shenzhen518055 China China Academy of Information and Communications Technology Beijing100191 China

Reconfigurable intelligent surface (RIS) constitutes an essential and promising paradigm that relies programmable wireless environment and provides capability for space-intensive communications, due to the use of low-cost massive reflecting elements over the entire surfaces of man-made structures. However, accurate channel estimation is a fundamental technical prerequisite to achieve the huge performance gains from RIS. By leveraging the low rank structure of RIS channels, three practical residual neural networks, named convolutional blind denoising network, convolutional denoising generative adversarial networks and multiple residual dense network, are proposed to obtain accurate channel state information, which can reflect the impact of different methods on the estimation performance. Simulation results reveal the evolution direction of these three methods and reveal their superior performance compared with existing benchmark schemes. Copyright © 2021, The Authors. All rights reserved.

关键词： Channel estimation

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Cooperative Pursuit with Multi-Pursuer and One Faster Free-moving Evader

arXiv

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arXiv 2020年

作者： Fang, Xu Wang, Chen Xie, Lihua Chen, Jie School of Electrical and Electronic Engineering Nanyang Technological University Singapore639798 Singapore Robotics Institute Carnegie Mellon University PittsburghPA15213 United States School of Electronics and Information Engineering Tongji University Shanghai200092 China Key Laboratory of Intelligent Control and Decision of Complex System Beijing Institute of Technology Beijing100081 China

—This paper addresses a multi-pursuer single-evader pursuit-evasion game where the free-moving evader moves faster than the pursuers. Most of the existing works impose constraints on the faster evader such as limited moving area and moving direction. When the faster evader is allowed to move freely without any constraint, the main issues are how to form an encirclement to trap the evader into the capture domain, how to balance between forming an encirclement and approaching the faster evader, and what conditions make the capture possible. In this paper, a distributed pursuit algorithm is proposed to enable pursuers to form an encirclement and approach the faster evader. An algorithm that balances between forming an encirclement and approaching the faster evader is proposed. Moreover, sufficient capture conditions are derived based on the initial spatial distribution and the speed ratios of the pursuers and the evader. Simulation and experimental results on ground robots validate the effectiveness and practicability of the proposed method. Copyright © 2020, The Authors. All rights reserved.

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An Improved Switching controller for Boost Converter Based on Hybrid Automata Model

An Improved Switching Controller for Boost Converter Based o...

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Chinese Automation Congress (CAC)

作者： Yi-Juan Ning Hai-Peng Ren Jie Li Shaanxi Key Laboratory of CoTplex System Control and Intelligent Information Processing Xi’an University of Technology Xi’an China Department of Electrical Engineering Xi’an University of Technology Xi’an China

Power electronic converters play an important role in the energy conversion. Power electronic converters, exhibiting different system dynamical characteristics according to the onoff state of the switch, are typical switching (nonlinear) systems. The traditional model of power electronic converter is the small signal average model and the converter controller is designed using the linear system theory. This kind of method is effective only within the vicinity of the predefined operating point. When the system parameter varies in a large scale, the converter control performance will degrade. The hybrid system model reflects the essential switching characteristics of the converter, and the controllers designed based on the hybrid model are suitable for converter control when the system states or parameters vary in a large scale. However, the parameter uncertainty is still a problem in conventional switching control method. In this paper, the inductor current compensation control is proposed to deal with the uncertainties of the circuit parameters and working point variation. The effectiveness of the proposed method is verified by both simulation and experiment.

关键词： Switches Voltage control Resistance Inductance Matrix converters

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Research on High Precision control of Joint Position Servo system for Hydraulic Quadruped Robot

Research on High Precision Control of Joint Position Servo S...

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第三十八届中国控制会议

作者： CHEN Zhihua WANG Shoukun XU Kang WANG Junzheng ZHAO Jiangbo NIU Shanshuai Key Laboratory of Intelligent Control and Decision of Complex Systems School of Automation Beijing Institute of Technology Key Laboratory of Servo Motion System Drive and Control Ministry of Industry and Information Technology School of Automation Beijing Institute of Technology

Electro-hydraulic servo valve-controlled cylinder(EHSVCC) is a highly integrated and high-performance electrohydraulic servo driving unit(EHSDU), which is the basic driving unit of the leg joint for hydraulic quadruped robot. The robot impedance control mostly adopts control methods based on position inner loop and impedance outer loop, the high precision control of position inner loop is the key to improve impedance control. Therefore, it is of great significance to study a high precision position control method. Firstly, the electro-hydraulic servo drive unit of the foot robot is taken as the research object. The model of the nonlinear system is established, and the feedback linearization of the system is carried out. Secondly, in order to improve the tracking performance and anti-jamming ability of the position inner loop input/output a sliding mode variable structure robust controller(SMVSRC) with switching function, variable structure control rate and improved boundary layer function is designed. Finally, the electro-hydraulic servo drive unit(EHSDU) and the hydraulic foot robot test platform are tested, the influence of the two control algorithms on the position response and tracking error for EHSDU is analyzed and compared under the control of sinusoidal signals with different amplitudes and frequencies and diagonal gait signals. The experimental results show that the improved SMVSRC algorithm is feasible and effective, which provides a theoretical basis for the later study of impedance control based on position inner loop.

关键词： Hydraulic quadruped robot Position control Feedback linearization Sliding mode controller

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Modeling and simulation of temperature distribution for planar cross-flow solid oxide fuel cell

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Energy Procedia 2019年 158卷 1585-1590页

作者： Yuan-wu Xu Xiao-long Wu Hang You Tao Xue Dong-qi Zhao Jian-hua Jiang Zhong-hua Deng Xiao-wei Fu Li Xi School of Automation Key Laboratory of Education Ministry for Image Processing and Intelligent Control Huazhong University of Science and Technology Wuhan 430074 China Hubei Province Key Laboratory of Intelligent Information Processing and Real-time Industrial System Wuhan University of Science and Technology Wuhan 430065 China Research Institute of Huazhong University of Science & Technology in Shenzhen Shenzhen 518057 China

Solid oxide fuel cell is a device that can convert chemical energy directly into electricity. Its advantages, such as high efficiency, low emission, quiet operation, fuel flexibility, bring about the broad application prospect. However, it is difficult to obtain the temperature distribution in the existing planar cross flow solid oxide fuel cell through the experiment. In this paper, a control orient two-dimensional differential equation model is established for a planar cross flow solid oxide fuel cell based on the finite node method, and an iterative algorithm for calculating the real time voltage of the fuel cell is proposed for the model. Based on the model, the temperature distribution of the fuel cell in the test and system configuration is simulated. The simulation results show that the model can reflect the thermoelectric characteristics of the planar cross flow solid oxide fuel cell, especially the temperature distribution of the fuel cell. The SOFC temperature distribution modeling in this paper is helpful for the development of temperature distribution observers and design related control methods in later studies.

关键词： modeling simulation temperature distribution planar cross flow solid oxide fuel cell

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Standby and Shutdown Cycles Modeling of SOFC Lifetime Prediction

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Energy Procedia 2019年 158卷 1573-1578页

作者： Wu Xiao-long Xu Yuanwu Xue Tao Zhao Dongqi Jiang Jianhua Deng Zhonghua Fu Xiaowei Li Xi School of Automation Key Laboratory of Education Ministry for Image Processing and Intelligent Control Huazhong University of Science and Technology Wuhan 430074 China Hubei Province Key Laboratory of Intelligent Information Processing and Real-time Industrial System Wuhan University of Science and Technology Wuhan 430065 China Shenzhen Huazhong University of Science and Technology Research Institute Shenzhen 518057 China

In order to more accurately predict the impact of solid oxide fuel cells to stack life on standby and shutdown, this paper proposes a modeling method based on experimental data. Which is based on Elman neural network(NN). At the same time, a main factor is considered in the modeling process which is the effect of cooling rate on the stack. In the process of modeling, the most obvious cooling rate is used to modeling. There are two different influencing factors on classify, the training set and the verification set respectively. After the reliability of the model, the Solid Oxide Fuel cell (SOFC) stack life prediction is carried out. From the predict results and the experimental results, it is found that the prediction results are good and the high precision.

关键词： Solid Oxide Fuel Cell(SOFC) Stack useful lifetime predict Cooling speed Gas composition Cycle standby shutdown

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A Human-Robot Skill Transfer Framework of Mobile Medical Robots for Autonomous Motion with Teaching by Demonstration

A Human-Robot Skill Transfer Framework of Mobile Medical Rob...

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International Conference on Advanced Robotics and Mechatronics (ICARM)

作者： Jiehao Li Junzheng Wang Shoukun Wang Hui Peng Qi Wen Longbin Zhang Meina Lin Politecnico di Milano Milan Italy State Key Laboratory of Complex System Intelligent Control and Decision Beijing Institute of Technology Beijing China College of Intelligence Science and Technology National University of Defense Technology Changsha China BioMEx Center KTH Mechanics KTH Royal Institute of Technology Stockholm Sweden Guangdong Key Laboratory of IoT Information Technology Guangdong University of Technology Guangzhou China

ISBN: (数字)9781728164793

ISBN: (纸本)9781728164809

The accuracy of autonomous motion is the main challenge for mobile medical robots, especially running in narrow space conditions to transport the casualties in the hospital. This article mainly centers on the human-robot transmission of the mobile medical robot for narrow space autonomous motion. In order to enable mobile medical robots to autonomously and smoothly transport hospital casualties through narrow aisles, in this paper, we present a robot skill transfer technology, namely a human-robot skill transfer framework of mobile medical robots for autonomous motion with teaching by demonstration, which is that a smooth optimal path is planned through the human motion, and then the Kinect sensor is used to detect human bone movement to learn its motion trajectory so as to achieve trajectory tracking control. Meanwhile, using the Remote Center of Motion (RCM) constraint to minimize the error between the actual trajectory of the medical robot and the tracking reference path to control the motion trajectory accurately, human-computer interactive mobile medical robots can smoothly pass through narrow channels. Through research and analysis, it is demonstrated that the mobile medical robot proposed in this paper has great feasibility, which is of great reference value in the field of medical rescue.

关键词： Medical robotics Education Trajectory Mobile robots Tracking Hospitals

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Infrared Dim and Small Target Detection and Tracking Based on Single Multi-Frame Algorithm under Sea Clutter Background

Infrared Dim and Small Target Detection and Tracking Based o...

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第三十八届中国控制会议

作者： Ting Zhao Taoshen Wang Yaoxin Cao Yunze Cai Key Laboratory of System Control and Information Processing Ministry of Education Department of Automation Shanghai Jiao Tong University Key Laboratory of Marine Intelligent Equipment and System of Ministry of Education Department of Automation Shanghai Jiao Tong University Shanghai Institute of Spaceflight Control Technology

Infrared dim and small target detection and track under sea clutter is significant and crucial in the infrared image process. It is a difficult task because of the disturbing clutter, the changing scenario and weak targets. In this paper, a complete process to detect and track dim small targets is proposed. Firstly, we use Mean and 3 D Filtering with Block-Matching(M3 DBM)algorithm to denoise infrared images. Inspired by the well-known BM3 D algorithm and NLM algorithm, M3 DBM can keep small targets from impair while denoising. Then, we use Butterworth high-pass filter and morphological filter to extract possible targets from single frame image. Finally, an optimal pipeline filtering algorithm(OPF) based on target position prediction and multi-target stable track is proposed. Optimal means that choose the best pipe for target and vice versa. OPF can track targets stably and accurately. The experimental results show that the proposed algorithm achieves good results in both accuracy and efficiency.

关键词： Infrared dim and small targets Sea clutter background M3DBM denoising Butterworth high-pass morphological Optimal pipeline filtering

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