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H_∞ Control of Looper-Tension Control systems Based on a Discrete-Time Model

Journal of Iron and Steel Research International 2013年第10期20卷 28-31页

作者： CHEN Jin-xiang YANG Wei-dong SUN Yan-guang State Key Laboratory of Hybrid Process Industry Automation Systems and Equipment Technology Automation Research and Design Institute of Metallurgical IndustryChina Iron and Steel Research Institute Group School of Automation and Electrical Engineering University of cience and Technology Beijing

High control performances cannot be obtained by most of the existing looper-tension control approaches through only considering controller designs based on continuous time models, which cannot meet the requirements of modern computer control systems with high control accuracy. In order to solve the above problems, a state feedback H∞ control method based on a discrete-time model for looper-tension control systems in hot rolling mills is presen- ted. The considered system is approximated by a discrete-time loope∞tension control system model. Based on a Lya- punov functional method, a state feedback H∞ control law is developed which makes the closed-loop system asymp totically stable with guaranteed H∞ performance. The controller gains are obtained by solving a set of linear matrix inequalities （LMIs）. In contrast to the existing results, the proposed approach can obtain good H∞ performance and effectively reduce external disturbances. The strip tension is also less affected by the change of looper angel, so good control performances can be obtained. Moreover, this control scheme is easy to implement, and can be applied to other linear systems. A simulation example with practical parameters is provided to illustrate the effectiveness of the developed method.

关键词： looper-tension control system H∞ control linear matrix inequality discrete-time system

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New Explorations on Cannon's Contributions and Generalized Solutions for Uniform Linear Motion Blur Identification

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Journal of Computer Science & Technology 2012年第1期27卷 174-186页

作者： Lu Wang Hong-Yan Zhang Si-Long Peng The National Engineering and Technology Research Center for ASIC Design Institute of AutomationChinese Academy of SciencesBeijing 100190China The Key Laboratory of Complex Systems and Intelligence Science Institute of AutomationChinese Academy of Sciences Beijing 100190China Sino-European Institute of Aviation Engineering Civil Aviation University of ChinaTianjin 300300China

Existing frequency-domain-oriented methods of parameter identification for uniform linear motion blur （ULMB） images usually dealt with special scenarios. For example, blur-kernel directions were horizontal or vertical, or degraded images were of foursquare dimension. This excludes those identification methods from being applied to real images, especially to estimate undersized or oversized blur kernels. Pointing against the limitations of blur-kernel identifications, discrete Fourier transform （DFT）-based blur-kernel estimation methods are proposed in this paper. We analyze in depth the Fourier frequency response of generalized ULMB kernels, demonstrate in detail its related phase form and properties thereof, and put forward the concept of quasi-cepstrum. On this basis, methods of estimating ULMB-kernel parameters using amplitude spectrum and quasi-cepstrum are presented, respectively. The quasi-cepstrum-oriented approach increases the identifiable blur-kernel length, up to a maximum of half the diagonal length of the image. Meanwhile, directing toward the image of undersized ULMB, an improved method based on quasi-cepstrum is presented, which ameliorates the identification quality of undersized ULMB kernels. The quasi-cepstrum-oriented approach popularizes and applies the simulation-experiment- focused DFT theory to the estimation of real ULMB images. Compared against the amplitude-spectrum-oriented method, the quasi-cepstrum-oriented approach is more convenient and robust, with lower identification errors and of better noiseimmunity.

关键词： Fourier amplitude spectrum phase perpendicular relation uniform linear motion blur identification quasicepstrum

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MAMOT: Memory-aware mapping optimization tool for MPSoC

MAMOT: Memory-aware mapping optimization tool for MPSoC

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15th Euromicro Conference on Digital System design, DSD 2012

作者： Jovanovic, Olivera Marwedel, Peter Bacivarov, Iuliana Thiele, Lothar Design Automation for Embedded Systems University of Dortmund Germany Computer Engineering and Networks Laboratory ETH Zuerich Switzerland

ISBN: (纸本)9780769547985

Mapping applications onto multiprocessor system-on-chip (MPSoC) devices is a well-known and complex optimization problem, receiving large interest in recent years. Diverse frameworks for mapping optimization have been developed, that typically distribute application tasks to available processors while optimizing one or more objectives such as performance and energy consumption. However, even though the memory subsystem is a resource that contributes drastically to the overall performance and energy consumption of the MPSoC, no mapping optimization framework is considering it so far. This paper addresses this challenge, and investigates the effect of memory hierarchies for MPSoC mapping. A memory-aware mapping optimization tool (that we refer to as MAMOT) has been developed for this purpose. We primarily focus on heterogeneous MPSoCs with heterogeneous memory hierarchies. Our evaluations show that considering memory mapping during MPSoC mapping optimization may reduce the application runtime up to 29.5% and its energy consumption up to 40%. © 2012 IEEE.

关键词： Multiobjective optimization

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Parameter identification of Bouc-Wen model applied to piezoelectric actuator modeling based on adaptive genetic algorithm

Parameter identification of Bouc-Wen model applied to piezoe...

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16th International Conference on Mechatronics Technology, ICMT 2012

作者： Liu, Xiang-Dong Cai, Chun-Xia Dong, Ning Qu, Yan Key Laboratory for Intelligent Control and Decision of Complex Systems Beijing Institute of Technology Beijing China School of Automation Beijing Institute of Technology Beijing China Wu Zhou Engineering and Design Institute Beijing China

ISBN: (纸本)9787900769428

In this paper, the Bouc-Wen model widely used in describing hysteretic systems is applied to piezoelectric actuator (PEA) modelling and real-coded adaptive genetic algorithm (GA) is adopted to identify the model parameters simultaneously. By dynamically adjusting the crossover probability and mutation probability, adaptive genetic algorithm improves the performance of local convergence and premature convergence and enhances search speed and precision of the simple genetic algorithm. Then some experiments are conducted to verify the efficiency of the identification method with satisfactory parameter identification results.

关键词： Piezoelectric actuators

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MAMOT: Memory-Aware Mapping Optimization Tool for MPSoC

MAMOT: Memory-Aware Mapping Optimization Tool for MPSoC

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Euromicro Symposium on Digital System design

作者： Olivera Jovanovic Peter Marwedel Iuliana Bacivarov Lothar Thiele Design Automation for Embedded Systems University of Dortmund Germany Computer Engineering and Networks Laboratory ETH Zurich Switzerland

关键词： Instruction sets Optimization Runtime Memory management Energy consumption Evolutionary computation

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Tracking control of an electrostatic torsional micromirror beyond the pull-in limit with enhanced performance

Tracking control of an electrostatic torsional micromirror b...

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International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO)

作者： Weijie Sun John T. W. Yeow Zhendong Sun College of Automation Science and Engineering South China University of Technology Guangzhou China Advanced Micro/Nano Devices Laboratory Systems Design Engineering University of Waterloo Waterloo ONT Canada

In this paper, we will study the output-error-constrained tracking control problem of an electrostatic torsional micromirror beyond the pull-in limit. We will first show that this problem can be formulated as a robust output regulation problem and it further boils down to a robust regulation problem with output-constrained by adaptive internal model design, the solution of which would in turn lead to the solution of the original problem. Then we design a regulation controller for such a regulation problem by using the barrier Lyapunov function technique. Our adaptive control law ensures the electrostatic torsional micromirror with a enhanced tracking performance in the sense that the moveable micromirror can achieve the sinusoidal wave scanning of any frequency up to a full gap operation without contacts of the fixed bottom electrode, and furthermore, the estimated sinusoidal wave frequency converges to its real value.

关键词： Micromirrors Electrostatics Robustness Lyapunov methods Electrodes Frequency control Frequency estimation

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Optimal control over unreliable networks with uncertain loss rates

Optimal control over unreliable networks with uncertain loss...

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作者： Kögel, Markus J. Blind, Rainer Allgöwer, Frank Institute for Systems Theory and Automatic Control University of Stuttgart Stuttgart Germany Laboratory for Systems Theory and Automatic Control Institute for Automation Engineering Otto-von-Guericke University Magdeburg Magdeburg Germany Design and Optimization in Chemical and Biochemical Process Engineering International Max Planck Research School for Analysis Magdeburg Germany

ISBN: (纸本)9781424474264

In this work, we consider an optimal control problem for Networked Control systems (NCS), where the loop is closed via an unreliable network. In order to inform the controller about the fates of the control packets, the actuator sends acknowledgements to the controller. In this work, different types of acknowledgements are considered. Since all packets are send over a network, we consequently assume, that all packets can get lost, i.e. the measurement packets, the control packets as well as the acknowledgement packets. The loss of these packets is modeled by independent and identically distributed (iid) Bernoulli processes. Finally, we assume that the parameters of these loss processes are not known exactly. Using this setup, we derive bounds for the uncertainty in the loss rates. Moreover, we present an algorithm to design a sub-optimal controller which can tolerate a given amount of network uncertainties. © 2010 AACC.

关键词： Networked control systems

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Analytical and experimental frequency response analysis of microcantilevers subject to tip-sample interaction

Analytical and experimental frequency response analysis of m...

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2009 ASME International design engineering Technical Conferences and Computers and Information in engineering Conference, DETC2009

作者： Delnavaz, Aidin Nima Mahmoodi, S. Jalili, Nader Zohoor, Hassan Center of Excellence in Design Robotics and Automation School of Mechanical Engineering Sharif University of Technology Tehran Iran Center for Vehicle Systems and Safety Virginia Tech Blacksburg VA 24061 United States Smart Structures and NEMS Laboratory Clemson University Clemson SC 29634 United States

ISBN: (纸本)9780791849033

Improvement of microcantilever-based sensors and actuators chiefly depends on how comprehensively they are modeled and precisely formulated. Atomic Force Microscopy (AFM) is the most widespread application of microcantilever beam as a sensor, which is usually influenced by the tip-sample interaction force. For this, vibration of AFM microcantilever probe is analyzed in this paper, along with analytical, numerical and experimental investigation of the influence of the sample interaction force on the microcantilever vibration. Nonlinear integro-partial equation of microcantilever vibration subject to the tip-sample interaction is then derived and numerically simulated. Moreover, multiple time scales method is utilized to estimate the tip amplitude while it is vibrating near the sample. An experimental setup is developed using. Copyright © 2009 by ASME.

关键词： Atomic force microscopy

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Qualitative study of nanoassembly process: 2-D molecular dynamics simulations

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Scientia Iranica 2010年第1 F期17卷 1-11页

作者： Mahboobi, S.H. Meghdari, A. Jalili, N. Amiri, F. Institute for Nanoscience and Nanotechnology Sharif University of Technology P.O. Box: 14588-89694 Tehran Iran Piezoactive Systems Laboratory Department of Mechanical and Industrial Engineering Northeastern University Boston MA 02115 United States Center of Excellence in Design Robotics and Automation School of Mechanical Engineering Sharif University of Technology P.O. Box 11155-9567 Tehran Iran

Precise positioning of nanoclusters through manipulation in the presence of other clusters is one of the main challenging tasks in nanoclusters assembly. Currently, the size of clusters which are used as building blocks is decreasing to a few nanometers. As a result, the particle nature of the matter has a crucial role in manipulator/cluster/substrate interactions. In order to understand and predict the behavior of nanoclusters during the positioning process, it is, therefore, essential to have a deep insight into the aforementioned nanoscale interactions, in this research, 2-D molecular dynamics simulations are used to investigate such behaviors. Performing the planar simulations can provide a rather satisfactory qualitative instrument for our aim while the computation time is considerably decreased in comparison with 3-D simulations. The system considered here is made up of a tip, two clusters and a substrate. The main focus here is on metallic nanoclusters. In order to study the behavior of the above system which is made up of different transition metals, Nose-Hoover dynamics and Sutton-Chen interatomic potential are used. Furthermore, the effect of the material characteristics, tip form and manipulation scheme on the success of the process are examined. Such qualitative simulation studies can pave the pathway towards certain nanopositioning scenarios when considering different working conditions before consuming largescale computation time or high experimental expenses. © Sharif University of Technology, June 2010.

关键词： Molecular dynamics

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Quantitative analysis of neural plasticity in motorcortex during functional recovery post spinal cord injury

Quantitative analysis of neural plasticity in motorcortex du...

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Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Yan Huo Ping Li Chaolin Ma Hang Zhang Bin Lv Jiping He Center of Neural Interface Design Arizona State University Tempe AZ USA School of Mechatronic Engineering Beijing Institute of Technology Beijing China Key Laboratory of Complex Systems and Intelligent Science Institute of Automation Chinese Academy and Sciences Beijing China Huazhong University of Science and Technology Wuhan China

The impact of spinal cord injury (SCI) on potential functional reorganization in neuronal populations in motor cortical areas remains unknown, though its influence on functional recovery may be significant. The cortical neuronal data was recorded from a monkey while it was trained to walk bipedally on a treadmill both before and after spinal cord injury. By using the correlation coefficients between different neurons, we constructed graphs for multiple steps in different sessions. The global efficiency of the graph was then calculated to investigate the effect of SCI on the neuronal activity patterns and how the correlation between the neurons changes as the functional recovery continued. Our results indicate that the observed significant changes in neuronal activity patterns in the motor cortex, although preliminary, suggest that the patterns of functional reorganization (neural plasticity) in motor areas of the cortex correlate and contribute to the functional recovery.

关键词： Neurons Correlation Synchronization Surgery Spinal cord injury Legged locomotion Leg

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