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DAMAGE CLASSIFICATION BY PROBABILISTIC NEURAL NETWORKS BASED ON LATENT COMPONENTS FOR time-varying system

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作者： KIM KwangHo GENG Yanfeng Yue Yaobin College of Information & Control Engineering China University of Petroleum(East China) Automation Engineering Faculty Kimchaek University of TechnologyCAS College of Automation & Electronic Engineering Qingdao University of Science & Technology

ISBN: (数字)9789881563934

ISBN: (纸本)9781538629185

In this paper,we presented the derivation of an adaptive algorithm for time-varying system and verified that it satisfied convergence *** on the concept of distance in parameter space,we proposed a robust identification method which identified the smallest set of discrete transfer functions under the assumption that its parameters were time-varying and described derivation of an adaptive law based on verification and update algorithm of the identified model *** also described that the proposed algorithm satisfied the convergence properties through numerical simulation.

关键词： adaptive algorithm time-varying system parameter estimation robust identification

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Transactions of Nanjing University of Aeronautics and Astronautics 2009年第4期26卷 259-267页

作者：袁健周燕吕欣南京航空航天大学航空宇航学院南京交通职业技术学院汽车工程系

A new approach to damage classification for health monitoring of a time-varylng system is presented. The functional-series time-dependent auto regressive moving average （FS-TARMA） time series model is applied to the vibration signal observed in the time-varying system for estimating the TAR/TMA parameters and the innovation variance. These parameters are the functions of the time, represented by a group of projection coefficients on the certain functional subspace with specific basis functions. The estimated TAR/TMA parameters and the innovation variance are further used to calculate the latent components （LCs） as the more informative data for health monitoring evaluation, based on an eigenvalue decomposition technique. LCs are then combined and reduced to numerical values （NVs） as feature sets, which are input to a probabilistic neural network （PNN） for the damage classification. For the evaluation of the proposed method, numerical simulations of the damage classification for a tlme-varylng system are used, in which different classes of damage are modeled by the mass or stiffness reductions. It is demonstrated that the method can identify the damages in the course of operation and the change of parameters on the time-varying background of the system.

关键词： damage detection time-varying system feature extraction/reduction probabilistic neural networks

New algorithm applied to vibration equations of time-varying system

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New algorithm applied to vibration equations of time-varying...

Input-Output Finite-time Guaranteed Cost Control for time-varying systems Based on an Aperiodic Adaptive Event-Triggered Mechanism

The 9th National Conference on Rheology

作者：陈锐林曾庆元张俊彦 School of Architectural and Civil Engineering Central South University College of Civil Engineering and Mechanics Xiangtan University

＜正＞Vibration equations of time-varying system are transformed to the form which is suitable to precise integration algorithm. Precision analysis and computation efficiency of new algorithm are *** following conclusions can be *** matrixes M,G and K is certainly *** can place left side of nonlinear terms of vibration equations of time-varying system into right side of equations in precise integration *** key of transformation from vibration equations of time-varying system to first order differential equations is to form matrix H,which should be assured to be *** suitable disposal, precision and computation efficiency of precise integration algorithms are greatly larger than those of general methods.

关键词： time-varying system vibration analysis precise integration algorithm

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Journal of systems Science & Complexity 2023年第3期36卷 1070-1088页

作者： CHEN Menghua WANG Yunming WANG Xinping School of Automation and Electrical Engineering Dalian Jiaotong UniversityDalian 116028China

This paper is concerned with the problem of input-output finite-time guaranteed cost control for a kind of time-varying systems(TVSs).To reduce the transmission burden,an aperiodic-sampling-based event-triggered mechanism is proposed with an adaptive *** a time-varying Lyapunov functional involving some time-dependent piecewise matrices is ***-output finite-time stability(IO-FTS)conditions are presented for the closed-loop *** resorting to properties of the matrix polynomial,input-output finite-time stabilization criterions are further derived by recursive linear matrix *** the sampled-data static output feedback controller can be *** addition,the corresponding optimization problem about minimum values of both the guaranteed cost bound and system output norm are ***,a spring-mass-damper system illustrates the effectiveness and superiority.

关键词： Aperiodic-sampling-based adaptive event-triggered mechanism guaranteed cost control input-output finite-time stability time-varying system

Parametric identification of time-varying systems from free vibration using intrinsic chirp component decomposition

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Acta Mechanica Sinica 2020年第1期36卷 188-205页

作者： Sha Wei Shiqian Chen Xingjian Dong Zhike Peng Wenming Zhang School of Mechanics and Engineering Science Shanghai UniversityShanghai200072China Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai200072China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai UniversityShanghai200072China State Key Laboratory of Mechanical system and Vibration Shanghai Jiao Tong UniversityShanghai200240China

time-varying systems are applied extensively in practical applications,and their related parameter identification techniques are of great significance for structural health monitoring of time-varying *** improve the identification accuracy for time-varying systems,this study puts forward a novel parameter identification approach in the time-frequency domain using intrinsic chirp component decomposition(ICCD).ICCD is a powerful tool for signal decomposition and parameter extraction,with good signal reconstruction capability in a high-noise *** maintain good identification effects for the time-varying system in a noisy environment,the proposed method introduces a redundant Fourier model for the non-stationary signal,including instantaneous frequency(IF)and instantaneous amplitude(IA).The accuracy and effectiveness of the proposed approach are demonstrated by a single-degree-of-freedom system with three types of time-varying parameters,as well as an example of a multi-degree-of-freedom *** effects of different levels of measured noise on the identified results are also discussed in *** results show that the proposed method is very effective in tracking the smooth,periodical,and non-smooth variations of time-varying systems over the entire identification time period even when the response signal is contaminated by intense noise.

关键词： system identification time-varying system time-frequency domain Intrinsic chirp component decomposition

On the Simultaneous Stabilization of Linear time-varying systems

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Journal of Mathematical Research with Applications 2016年第3期36卷 341-350页

作者： Shuyan SONG Liu LIU Yufeng LU School of Mathematical Science Dalian University of Technology

In this paper, we consider the simultaneous stabilization of discrete linear timevarying systems in an operator-theoretic framework. We give a criterion of simultaneous stabilization on account of one kind of strong r... 详细信息

关键词： strong representation simultaneous stabilization time-varying system nest algebra

Spatiotemporal Input Control:Leveraging Temporal Variation in Network Dynamics

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IEEE/CAA Journal of Automatica Sinica 2022年第4期9卷 635-651页

作者： Yihan Lin Jiawei Sun Guoqi Li Gaoxi Xiao Changyun Wen Lei Deng H.Eugene Stanley the Department of Precision Instrument Tsinghua University the Department of Bio-engineering Stanford University IEEE the Institute of Automation Chinese Academy of Sciences the School of Electrical and Electronic Engineering Nanyang Technological University Department of Physics and Center for Polymer Studies Boston University

The number of available control sources is a limiting factor to many network control tasks.A lack of input sources can result in compromised controllability and/or sub-optimal network performance,as noted in engineering applications such as the smart *** mechanism can be explained by a linear timeinvariant model,where structural controllability sets a lower bound on the number of required *** by the ubiquity of time-varying topologies in the real world,we propose the strategy of spatiotemporal input control to overcome the source-related limit by exploiting temporal variation of the network *** theoretically prove that under this regime,the required number of sources can always be reduced to *** is further shown that the cost of control depends on two hyperparameters,the numbers of sources and intervals,in a trade-off *** a demonstration,we achieve controllability over a complex network resembling the nervous system of Caenorhabditis elegans using as few as 6%of the sources predicted by a static control *** example underlines the potential of utilizing topological variation in complex network control problems.

关键词： Complex network complex system control theory complex system optimization temporal network time-varying system

Pilot time-varying control behavior modeling in refractory period with aircraft failures

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Science China(Technological Sciences) 2023年第7期66卷 2000-2012页

作者： XU ShuTing TAN WenQian WANG WeiJun SUN LiGuo School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Nanchang 330000China

Modeling human pilot control behavior aims to understand and describe how humans control aircrafts and devices,to provide a foundation for the study of the dynamic characteristics of the human-vehicle *** the presence of aircraft failures,the human pilot has a control process of the refractory period,which may cause adverse aircraft-pilot couplings,and even lead to loss-of-control *** refractory period will make the pilot emerge with time-varying and adaptive *** paper investigates how pilot control behavior changes to adapt to the aircraft failure situation and develops a time-varying pilot model during the refractory *** aviation pilots performed a human-in-the-loop simulation experiment on a ground flight simulator to simulate the failure situations for a pitch-tracking *** characterize the pilot’s time-varying response mechanism,a time-frequency-spectrum method was used to analyze the pilot control *** innovations in the proposed model can be embodied in the description of the fuzziness,time-varying,and adaptation of the pilot for the failures in the refractory *** on fuzzy logic theory,the pilot’s judgment and identification of failures are *** adaptation of manual control behavior to time-varying aircraft dynamics is depicted by adaptive model ***-domain and time-frequency-spectrum analysis show that the simulation results of the pilot model are consistent with the human-in-the-loop experimental *** model simulation evaluations are within the range of the experimental evaluation,which shows the rationality of the timevarying behavior model of the human pilot in a failure refractory *** model has practical values for guiding the pilot to deal with abnormal conditions and predicting nonlinear aircraft-pilot couplings.

关键词： time-varying system human pilot model fuzzy control simulation aircraft-pilot couplings

Stability analysis of golden-section adaptive control systems based on the characteristic model

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Science China(Information Sciences) 2017年第9期60卷 253-270页

作者： Duoqing SUN Institute of Mathematics and systems Science Hebei Normal University of Science and Technology Beijing Institute of Control Engineering China Academy of Space Technology

All-coefficient adaptive control theory and method based on characteristic models have already been applied successfully in the fields of astronautics and industry. However, the stability analysis of the characteristic model-based golden-section adaptive control systems is still an open question in both theory and practice. To investigate such stability issues, the author first provides a method for choosing initial parameter values and new performances for a projection algorithm with dead zone for adaptive parameter estimation, and develops some properties of time-varying matrices by utilizing some algebraic techniques. And then a new Lyapunov function with logarithmic form for time-varying discrete systems is constructed. Finally, the author transforms the characteristic models of some multi-input and multi-output(MIMO) controlled systems into their equivalent form, and proves the stability of the closed-loop systems formed by the golden-section adaptive control law based on the characteristic model using mathematical techniques.

关键词： characteristic model golden-section control law stability time-varying system nonlinear system