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Facial expression recognition based on deep residual network

Journal of Computers (Taiwan) 2020年第2期31卷 12-19页

作者： Qu, Junsuo Zhang, Ruijun Zhang, Zhiwei Pan, Jeng-Shyang Xi'an Key Laboratory of Advanced Control and Intelligent Process School of Automation Xi'an University of Posts and Telecommunications Xi'an710061 China Innovation Lab Xi'an University of Posts and Telecommunications Xi'an710061 China School of Information Science and Engineering Fujian University of Technolgy Fuzhou350000 China

Low accuracy of facial expression recognition for traditional methods, a facial expression recognition algorithm is proposed. Using the deep residual network model as the feature extractor, the residual block of the residual network is improved to enhance the information flow in the deep network. During training, apply some pre-processing techniques to extract only expression specific features from a face image and explore the presentation order of the samples and use softmax to classify and identify the extracted feature vectors. The experimental results show that a higher recognition rate is obtained on FER-2013. © 2020 Computer Society of the Republic of China. All rights reserved.

关键词： Face recognition

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A Primal-Dual SGD Algorithm for Distributed Nonconvex Optimization

arXiv

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arXiv 2020年

作者： Yi, Xinlei Zhang, Shengjun Yang, Tao Chai, Tianyou Johansson, Karl H. The Division of Decision and Control Systems School of Electrical Engineering and Computer Science KTH Royal Institute of Technology Stockholm100 44 Sweden The Department of Electrical Engineering University of North Texas DentonTX76203 United States The State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Shenyang110819 China

The distributed nonconvex optimization problem of minimizing a global cost function formed by a sum of n local cost functions by using local information exchange is considered. This problem is an important component of many machine learning techniques with data parallelism, such as deep learning and federated learning. We propose a distributed primal–dual stochastic gradient descent (SGD) algorithm, suitable for arbitrarily connected communication networks and any smooth (possibly nonconvex) cost functions. We show that the proposed algorithm achieves the linear speedup convergence rate O(1/√nT) for general nonconvex cost functions and the linear speedup convergence rate O(1/(nT)) when the global cost function satisfies the Polyak–Lojasiewicz (P–L) condition, where T is the total number of iterations. We also show that the output of the proposed algorithm with constant parameters linearly converges to a neighborhood of a global optimum. We demonstrate through numerical experiments the efficiency of our algorithm in comparison with the baseline centralized SGD and recently proposed distributed SGD algorithms. Copyright © 2020, The Authors. All rights reserved.

关键词： Cost functions

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Oil-water two-phase flow velocity measurement with Continuous wave ultrasonic Doppler 22

Oil-water two-phase flow velocity measurement with Continuou...

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22nd World Congress of the International Measurement Confederation, IMEKO 2018

作者： Liu, Weiling Tan, Chao Dong, Feng Tianjin Key Laboratory of Process Measurement and Control School of Electrical Engineering and Automation Tianjin University Tianjin300072 China

Oil-water two-phase flow exists widely in many industries. Accurate measurement of flow velocity is of significance for quantify the volume or mass flow rate as well as monitor the operation safety. A non-intrusive one-side Continuous Wave Ultrasonic Doppler (CWUD) sensor is presented for measuring the overall superficial velocity of oil-water two-phase flow. The one-side CWUD sensor consists of two-chip transducer with resonant frequency of 1MHz, both of which are installed at the bottom of test pipe, and the sample volume cover the whole radial direction of pipe cross-section. The Doppler shift signal collected by ultrasonic sensor is directly related to the average velocity of dispersed phase within the sample volume of CWUD. The overall superficial flow velocity is derived by a linear correction of measured average velocity, based on the analysis of average Doppler shift properties in different flow conditions, i.e. water continuous flow and oil continuous flow. Dynamic experiments were conducted at a horizontal oil-water two-phase flow loop. It can be found that the average Doppler shift within the sample volume increases with overall superficial flow velocity, however, varies with different continuous phases at the same overall superficial flow velocity. The results show that the mean relative error of overall superficial flow velocity is 3.45%. © 2018 Web Portal IOP. All rights reserved.

关键词： Flow velocity

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Dead-Time Compensator for State-delay Stable Systems

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IFAC-PapersOnLine 2018年第18期51卷 672-677页

作者： Albertos, P. García, P. Chen, Q. Luan, X. Department of Systems Engineering Control Instituto de Automática e Informática Industrial Universitat Politècnica deValència Spain Key Laboratory of Advance Process Control for Light Industries Institute of Automation Jiangnan University China

This paper deals with the control of simple process models with state-delays. A pre-compensator is used to cancel the delay. Due to the cancellation of some terms, the process as well as its undelayed part should be stable. Although the approach is general, in order to simplify the notation, second order systems are considered to describe the procedure. The proposed methodology is applied to compensate the delay in a recycled reactor as well as to control a pure state-delayed academic example. © 2018

关键词： process control Delay control systems Recycling control design Dead time compensator Dead time compensation Pre compensator Second order systemss Stable systems State delay Time delay systems

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Retraction Note: Evaluation on diabetic plantar pressure data-set employing auto-segmentation technologies

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Neural Computing and Applications 2024年第24期36卷 15219-15219页

作者： Chen, Hongwei Cao, Luying Li, Zairan Hemanth, D. Jude Wu, Lijun de Albuquerque, Victor Hugo C. Shi, Fuqian Department of Orthopedics Yiwu Central Hospital Wenzhou Medical University Wenzhou People’s Republic of China Institute of Digitized Medicine Wenzhou Medical University Wenzhou People’s Republic of China Tianjin Key Laboratory of Process Measurement and Control School of Electrical Engineering and Automation Tianjin University Tianjin People’s Republic of China Department of ECE Karunya University Coimbatore India Programa de Pós-Graduação Em Informática Aplicada Universidade de Fortaleza Fortaleza Brazil

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Preface——Special Issue on New Directions in Nonlinear and Distributed control

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Journal of Systems Science & Complexity 2018年第1期31卷 1-3页

作者： LIU Tengfei XIN Bin JIANG Zhong-Ping State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Shenyang 110819 China School of Automation State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing Advanced Innovation Center for Intelligent Robots and Systems Beijing Institute of Technology Beijing 100081 China Tandon School of Engineering New York University Brooklyn NY 11201 USA

Nonlinearity is ubiquitous in engineering and natural *** development of nonlinear control can be traced back to decades *** date,the research has reached the stage that emphasizes developing methodologies that can ha... 详细信息

关键词：控制问题非线性分布式工程应用程序电子物理自然系统生产线相互作用

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Stability Analysis and Design of Switched Saturated Systems Based on Antiwindup Technique

Stability Analysis and Design of Switched Saturated Systems ...

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Chinese control Conference (CCC)

作者： Xinquan Zhang Xiaoyin Li Yuzhong Wang Ke Mu School of Information and Control Engineering Liaoning Shihua University Fushun P. R. China School of Foreign Languages Liaoning Shihua University Fushun P. R. China State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Shenyang P. R. China

ISBN: (数字)9789881563903

ISBN: (纸本)9781728165233

The problem of stability analysis and anti-windup design is investigated for a class of switched linear systems subject to actuator saturation by using the common Lyapunov function method. Suppose that a group of dynamic output controllers have been designed and they can stabilize the closed-loop system in the absence of saturation. Then, the anti-windup compensators are designed, which aims for enlarging the domain of attraction of system with saturation. Finally, the anti-windup compensators are calculated by solving an optimization problem with linear matrix inequalities (LMI) constraints. A numerical example is given to show the effectiveness of proposed method.

关键词： Switches Actuators Switched systems Symmetric matrices Lyapunov methods Stability analysis Linear matrix inequalities

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L2-gain Analysis for Switched Saturated Systems Based on Anti-windup Technique

L2-gain Analysis for Switched Saturated Systems Based on Ant...

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Chinese control Conference (CCC)

作者： Xinquan Zhang Xiaoyin Li Jiasheng Shi Shizhong Tong School of Information and Control Engineering Liaoning Shihua University Fushun P. R. China School of Foreign Languages Liaoning Shihua University Fushun P. R. China State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Shenyang P. R. China

ISBN: (数字)9789881563903

ISBN: (纸本)9781728165233

In this paper, the problem on L 2 -gain analysis and anti-windup design is studied for linear switched saturated systems by the common Lyapunov function method. Firstly, the sufficient condition about tolerable disturbances is obtained and under this condition, the state trajectory that starts from the origin will be still on a bounded set. Then, we obtain the upper bound for restricted L 2 -gain. Furthermore, to determine the maximum capability of disturbance tolerance and the minimum upper bound of restricted L 2 -gain, the anti-windup compensators are computed by solving a constraints optimization problem. Finally, a numerical example is given to verify the effectiveness of proposed approach.

关键词： Switches Lyapunov methods Switched systems Actuators Electronic mail Trajectory

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Exact Computation of Delay Margin by PID control: It Suffices to Solve a Unimodal Problem!

Exact Computation of Delay Margin by PID Control: It Suffice...

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第三十八届中国控制会议

作者： Jianqi Chen Dan Ma Yong Xu Jie Chen Department of Electronic Engineering City University of Hong Kong College of Information Science and Engineering State Key Laboratory of Synthetical Automation for Process Industries Northeastern University The School of Automation Guangdong Provincial Key Laboratory of Intelligent Decision and Cooperative Control Guangdong University of Technology

In this paper we study delay robustness of PID controllers in stabilizing systems containing uncertain, variable *** consider second-order unstable systems and seek analytical characterization and exact computation of the PID delay margin,where by PID delay margin we mean the maximal range of delay values within which the system can be robustly stabilized by a PID controller. Our contribution is threefold. First, we show that the delay margin achieved by PID control coincides with that by PD controllers. Second, we show that other than helping stabilize the delay-free part of a plant, the proportional control contributes no action to increase the delay margin. Finally, we show that the PID delay margin can be computed efficiently by solving a unimodal problem, that is, a univariate optimization problem that admits a unique maximum and hence is a convex optimization problem in one variable. This unimodal problem is one of pseudo-concave optimization and hence can be solved using standard convex optimization or gradient-based methods. As such, from a computational perspective, the PID delay margin problem is completely resolved in this paper! The results not only insure that the PID delay margin problem be readily solvable, but also provide fundamental conceptual insights into the PID control of delay systems, and analytical justifications to long-held engineering intuitions and heuristics, thus lending useful guidelines in the tuning and analytical design of PID controllers.

关键词： Delay margin robust stabilization PID controller uncertain time delay nonlinear programming pseudo-concavity

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Delays in Model Reduction of Chemical Reaction Networks

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IFAC-PapersOnLine 2018年第14期51卷 100-105页

作者： Lipták, György Hangos, Katalin M. Process Control Research Group Systems and Control Laboratory Computer and Automation Research Institute Hungarian Academy of Sciences P.O. Box 63 BudapestH-1518 Hungary Department of Electrical Engineering and Information Systems University of Pannonia Veszprém Hungary

A novel engineering model reduction method is proposed in this paper that can be applied to a chemical reaction network (CRN) with chains of linear reactions. The reduced model is a delayed CRN with possibly different delays but with less state variables than the original model. As the first step of the model reduction, a decomposition method is also developed to transform chains with joint reactions into independent chains of linear reactions. The well known example of McKeithan's network is used as a case study to illustrate the basic concepts and the design method. © 2018

关键词： Reduction

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