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Structure-free containment control for uncertain underactuated multiple Euler-Lagrange systems

Science China(Information Sciences) 2023年第11期66卷 150-168页

作者： Housheng SU Yali WU Liren ZHANG Xia CHEN Key Laboratory of Image Processing and Intelligent Control of Education Ministry of China School of Artificial Intelligence and Automation Huazhong University of Science and Technology State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology

This article studies the problem of structure-free distributed containment control for uncertain underactuated multiple Euler-Lagrange systems(MELSs) considering disturbances by using a layered approach. First, the second layer is the virtual layer constructed artificially for hierarchical control. We move all virtual nodes to the convex hull formed by leaders in the first layer by implementing containment control algorithms on all virtual nodes. Then, the third layer is the following layer, and we propose an adaptive robust tracking controller to ensure that each follower in the third layer tracks the corresponding virtual node in the second layer. So far, the underactuated MELSs can achieve containment control. Furthermore,through the theoretical derivation, sufficient conditions are obtained to achieve the objective of structure-free containment control. Finally, the effectiveness of the proposed stratified structure-free containment control method is verified by a simulation example.

关键词： Euler-Lagrange systems underactuated system containment control adaptive-robust control

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Magnetic, magetostrictive properties, spin reorientation and M(o)ssbauer effect of Tb0.3Dy0.7-xPrx(Fe0.9Al0.1)1.95 alloys

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中国科学G辑(英文版) 2009年第1期52卷 52-57页

作者： ZHENG XiaoPing ZHANG PeiFeng FAN DuoWang LI FaShen Institute of Electronic Information Science and Technology Lanzhou City University Lanzhou 730070 China Key Laboratory of Opto-Electronic Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University Lanzhou 730070 China Key Laboratory of Opto-Electronic Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University Lanzhou 730070 China Key Laboratory for Magnetism and Magnetic Materials Ministry of Education Lanzhou University Lanzhou 730000 Key Laboratory for Magnetism and Magnetic Materials Ministry of Education Lanzhou University Lanzhou 730000 China

The effect of Pr substitution for Dy on the magnetic and magnetostrictive properties, anisotropy, spinreorientation and Mossbauer effect of a series of Tb0.3Dy0.7-xPrx(Fe0.9Al0.1)1.95(x=0, 0.1, 0.20, 0.25, 0.30, 0.35) alloys at room temperature have been investigated. It was found that a small amount of Pr sub-stitution is beneficial to a decrease in the magnetocrystalline anisotropy for the Tb0.3Dy0.7-xPrx(Fe0.9Al0.1)1.95 alloys. The magnetostriction decreases drastically with increasing x and the magnetostrictive effect disappears for x0.2. However, the magnetostriction exhibits a slightly bigger value at x=0.1 than the free alloys and is saturated more easily with the magnetic field H. The saturation magnetization and Curie temperature decrease monotonously, but the spontaneous magnetostriction increases linearly with increasing x, whereas the spin reorientation temperature increases first, then decreases rapidly and reaches the maximum at x=0.1. The analysis of Mossbauer spectra indicated that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry with the Pr concentration x, namely spin reorientation. Compared with AI substitution for Fe, the effect of Pr substitution for Dy on spin reorientation is relatively small. The hyperfine field increases with Pr concentration increasing, and the isomer shifts and the quadrupole splitting (QS) show weak concen-tration dependence.

关键词： magnetostriction anisotropy spin reorientation Mossbauer

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Structure, spin reorientation and M(o)ssbauer effect studies of Tb0.3Dy0.7(Fe1-xAlx)1.95 alloys

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中国科学G辑（英文版） 2006年第2期49卷 149-157页

作者： ZHENG Xiaoping ZHANG Peifeng FAN Duowang LI Fashen HAO Yuan Key Laboratory of Opto-Electronic Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University Lanzhou 730070 China Institute of Electronic Information Science and Technology Lanzhou Teachers College Lanzhou 730070 China State Key Lab. of Advanced Non-Ferrous Materials Gansu Province Lanzhou University of Technology Lanzhou 730050 China Key Laboratory of Opto-Electronic Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University Lanzhou 730070 China Key laboratory for Magnetism and Magnetic Materials Ministry of Education Lanzhou University Lanzhou 730000 China Key Laboratory of Opto-Electronic Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University Lanzhou 730070 China Key laboratory for Magnetism and Magnetic Materials Ministry of Education Lanzhou University Lanzhou 730000 China State Key Lab. of Advanced Non-Ferrous Materials Gansu Province Lanzhou University of Technology Lanzhou 730050 China

The effect of Al substitution for Fe on crystal structure, magnetostriction and spontaneous magnetostriction, anisotropy and spin reorientation of a series of polycrystalline Tb0.3Dy0.7(Fe1-xAlx)1.95 alloys (x = 0, 0.05, 0.1, 0.15, 0.20, 0.25, 0.30, 0.35) at room temperature and 77 K was investigated systematically. It was found that the primary phase of Tb0.3Dy0.7(Fe1-xAlx)1.95 is the MgCu2-type cubic Laves phase structure when x < 0.4 and the lattice constant a of Tb0.3Dy0.7(Fe1-xAlx)1.95 increases approximately and monotonically with the increase of x. The substitution of Al leads to the fact that the magnetostriction ( inceases slightly in a low magnetic field (H ≤ 40 kA/m), but decreases sharply and is easily close to saturation in a high applied field as x increases, showing that a small amount of Al substitution is beneficial to a decrease in the magnetocrystalline anisotropy. It was also found that the spontaneous magnetostriction (ζ)111 decreases greatly with x increasing. The analysis of the M(o)ssbauer spectra indicated that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry with the changes of composition and temperature, namely spin reorientation. A small amount of non-magnetic phase exists for x = 0.15 in Tb0.3Dy0.7(Fe1-xAlx)1.95 alloys and the alloys become paramagnetic for x > 0.15 at room temperture, but at 77 K the alloys still remain magnetic phase even for x = 0.2. At room temperature and 77 K, the hyperfine field decreases and the isomer shifts increase with Al concentration increasing.

关键词： magnetostriction cubic Laves phase spin reorientation M(o)ssbauer

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An Improved Levenberg-Marquardt Algorithm with Adaptive Learning Rate for RBF Neural Network 35

An Improved Levenberg-Marquardt Algorithm with Adaptive Lear...

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第35届中国控制会议

作者： AN Ru LI Wen Jing Han Hong Gui QIAO Jun Fei College of Electronic and Control Engineering Beijing University of Technology Beijing Key Laboratory of Computational Intelligence and Intelligent System

ISBN: (纸本)9781509009107

In this paper,an improved Levenberg-Marquardt(LM) algorithm with adaptive learning rate is proposed to optimize the learning process of RBF neural ***,an improved LM algorithm is adopted using a quasi-Hessian matrix and gradient vector which are computed *** with the conventional LM algorithm,Jacobian matrix multiplication and storage are not required in the improved LM algorithm,which can reduce computation cost and solve the problem of memory ***,the adaptive learning rate is integrated into the improved LM algorithm in order to accelerate the convergence speed of training algorithm and improve the network performance of nonlinear system ***,several experiments are conducted and the results show that the proposed method has faster convergence speed and better prediction performance.

关键词： Improved LM algorithm RBF neural network adaptive learning rate fast convergence speed

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Design of a Self-organizing Recurrent RBF Neural Network Based on Spiking Mechanism 35

Design of a Self-organizing Recurrent RBF Neural Network Bas...

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第35届中国控制会议

作者： LU Chao HAN Honggui QIAO Junfei YANG Cuili College of Electronic and Control Engineering Beijing University of Technology Beijing Key Laboratory of Computational Intelligence and Intelligent System

ISBN: (纸本)9781509009107

Based on the systemic investigation of recurrent neural network,a self-organizing recurrent radial basis function(SR-RBF) neural network which based on the spiking mechanism and improved Levenberg-Marquardt(LM) algorithm is proposed in this *** hidden neuron in the recurrent radial basis function(RRBF) can be added or pruned by computing the spiking strength of the connections between hidden and output neurons of RRBF neural ***,to ensure the accuracy of SR-RBF neural network,the parameters are trained by improved LM *** SR-RBF neural network is used for approximating the time-series prediction and classical non-linear ***,comparisons with other methods demonstrate that the SR-RBF neural network is more effective in terms of accuracy,generalization,and network structure.

关键词： Self-organizing spiking mechanism recurrent radial basis function time-series prediction

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Design of a High Performance Monolithic Current-Mode Boost DC-DC Converter

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电子学报(英文版) 2006年第4期15卷 599-603页

作者： YU Hua ZOU Xuecheng CHEN Chaoyang ZHANG Jing Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory for Image Processing and Intelligence Control Institute for Pattern Recognition and Artificial Intelligence Huazhong University of Science and Technology Wuhan 430074 China

The work presented in this paper mainly focuses on designing a monolithic current-mode boost DC-DC converter with integrated 22V DMOS FET power switch and control circuits. The boost converter operating at fixed frequency of 1.6MHz has been fabricated with a 1.5μm Bipolar-CMOS-DMOS (BCD) process. The chip with features of wide input voltage range (2.7V to 14V), high efficiency over large load range (1mA to 500mA), low shutdown current, fast transient response and low power, was designed for mobile power management applications. Besides issues such as technology choice, power switch optimization and ramp compensation, the paper also copes with the monolithic switching noise in switching power IC circuits.

关键词： DC-DC转换器变速补偿电流控制脉冲调制

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The influence of the growth temperature on the doping characteristics of P-GaP layers in AlGaInP red LED

The influence of the growth temperature on the doping charac...

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2010 OSA-IEEE-COS Advances in optoelectronics and Micro/Nano-Optics, AOM 2010

作者： Luo, Shaojun Deng, Jun Li, Jianjun Gao, Linchun Chen, Rui Han, Jun College of Electronic Information and Control Engineering Key Laboratory of Opto-electronics Technology Beijing University of Technology Beijing China

ISBN: (纸本)9781424483938

The doping characteristics of P-GaP layer in AlGaInP red LED has been studied, by changing the low pressure metal organic chemical vapor deposition (LP-MOCVD) system's growth temperature. Several epitaxial samples, which grown at different temperatures of LP-MOCVD, have been tested by ECV *** results have been shown,that the doping density and the suface of GaP layer and the characteristics of the LED changed with the growth temperature of GaP layers. This experience can be used for the fabrication of high-performance AlGaInP red LED.

关键词： III-V semiconductors

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Breakdown Voltage Research of Penning Gas Mixture in Plasma Display Panel

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Plasma Science and technology 2005年第6期7卷 3127-3131页

作者：郭滨刚刘纯亮宋忠孝范玉锋夏星刘柳范多旺 Key Laboratory for Physical Electronics and Devices under Ministry of Education Xi'an Jiaotong UniversityXi'an 710049 China Key Laboratory of Opto-Electronic Technology and Intelligent Control under Ministry of Education Lanzhou Jiaotong UniversityLanzhou 730070 China

Paschen law and equations, which ignore the influence of the Penning ionization on the electron ionization coefficient （α）, are always used as the approximation of the breakdown voltage criterion of the Penning gas mixture in current researches of discharge characteristics of the plasma display panel （PDP）. It is doubtful that whether their results match the facts. Based on the Townsend gas self-sustaining discharge condition and the chemical kinetics analysis of the Penning gas mixture discharging in PDP, the empirical equation to describe the breakdown of the Penning gas mixture is given. It is used to calculate the breakdown voltage curves of Ne-Xe/MgO and Ne-Ar/MgO in a testing macroscopic discharge cell of AC-PDP. The effective secondary electron emission coefficients （γeff） of the MgO protective layers are derived by comparing the breakdown voltage curves obtained from the empirical equation with the experimental data of breakdown voltages. In comparison with the results calculated by the Paschen law and the equation which ignore the influence of the Penning ionization on α , the results calculated by the empirical equation have better conformity with experimental data. The empirical equation characterizes the breakdown of the Penning gas mixture in PDP effectively, and gives a convenient way to study its breakdown characteristics and the secondary electron emission behaviors.

关键词： plasma display panel (PDP) Penning gas mixture breakdown voltage the effective secondary electron emission coefficient

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Study of double closed-loop fuzzy control base on parallel-type inverted pendulum

Study of double closed-loop fuzzy control base on parallel-t...

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2010 IEEE International Conference on Intelligent Computing and Intelligent Systems, ICIS 2010

作者： Hou, Tao Fan, Duo-Wang Key Laboratory Opto-Electronic Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University Lanzhou China

ISBN: (纸本)9781424465835

The main purpose of this paper is to demonstrate a double closed-loop fuzzy control approach base on Bang-Bang control for the parallel-type inverted pendulum system with multi-variable and nonlinear characteristic. In this approach, firstly, judge the initial state of system and according to the judgment switch the state to make control system enter a controlled state. Then, the position of the small car and the angle of the double swing pendulum are controlled by the double closed-loop fuzzy control. The digital simulation results are in line with the theory analysis and it can be seen that this method is feasible. Thus it should be of interest to control theory. ©2010 IEEE.

关键词： Inverted pendulum

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Multi-objective Design of the Water Distribution Systems Using SPEA2 35

Multi-objective Design of the Water Distribution Systems Usi...

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第35届中国控制会议

作者： MENG Qinchao QIAO Junfei YANG Cuili College of Electronic Information and Control Engineering Beijing University of Technology Beijing Key Laboratory of Computational Intelligence and Intelligent System

ISBN: (纸本)9781509009107

As a complicated and combinatorial optimization problem, the design of Water distribution systems(WDSs) is difficult to be solved. In this paper, in order to design WDSs better, three objectives are considered, including the initial construction cost, the sum of node surplus head and the variance of node surplus head. The consideration of the variance of node surplus head can reflect the distribution of the node surplus head in WDSs. This problem is solved by the strength pareto evolutionary algorithm(SPEA2). Finally, the model is applied into two well-known benchmark case studies, the two-loop network and the New York Tunnels network. By comparing with some algorithms, such as Tabu search algorithm and non-dominated sorting genetiv algorithm(NSGA2), the performance of SPEA2 shows the effectiveness in terms of reliability, convergence, as well as diversity.

关键词： Multi-objective optimization Water distribution systems SPEA2

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