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Control Theory and Technology 2015年第1期13卷 29-36页

作者： BAJARANGBALI Somanath MAJHI Department of Electronics and Electrical Engineering Indian Institute of Technology Guwahati

This paper presents identification of second order plus dead time （SOPDT） integrating and critically damped systems based on relay feedback testing. Relay with hysteresis is applied to the unknown system to get the sustained oscillations also called as limit cycle. The limit cycle parameters are utilized in mathematical expressions which are derived using state space technique so that exact process model parameters are estimated. As the relay with hysteresis helps in generating sustained oscillations and also reduces effect of measurement noise which is an important issue in system identification. Different types of processes in the form of transfer function models are considered to show the efficacy of the proposed method and results are compared with available methods in the literature with and without noise effect.

关键词： System identification time delay systems relay with hysteresis

Optimal Sliding Mode Control for Uncertain systems with time delay

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Optimal Sliding Mode Control for Uncertain Systems with Time...

Parametric Identification of Input-delay systems with Unknown time delay

2010 Chinese Control and Decision Conference

作者： Rui Dong~1,Gongyou Tang~2,Yunrui Guo~1 1.Department of Mathematics,Henan Institute of Science and Technology,Xinxiang 453003,China 2.College of Information Science and Engineering,Ocean University of China,Qingdao 266071

＜正＞This paper considers the sliding mode control for linear systems with time-delay affected by *** using the successive approximation approach,a novel time-varying sliding surface is designed in an optimal fashion. The stability of the sliding mode is *** switching manifold assures that the state trajectories of the closed-loop system converge to *** convergence speed of every state trajectory on the ideal sliding surface can be adjusted through choosing the parameters of the quadratic performance index.A disturbance observer is constructed to make the control input physically realizable.A numerical simulation is given to show the effectiveness of the proposed design approach.

关键词： time delay systems Optimal Control Stability Switching Functions

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Parametric Identification of Input-delay Systems with Unknow...

Stochastic Resonance in a time-delayed Bistable System Driven by Square-Wave Signal

第二十六届中国控制会议

作者： Najafi Majd aldin Kamali Marzieh Askari Javad Electrical & Computer engineering Department Isfahan University of Technology

In this paper,a method is presented for on-line identification of systems with unknown time *** method is based on two parametric models of system that one of them is defined for transfer function parameters estimation and the other one is defined for delay value *** algorithm is used for estimating transfer function parameters and a new algorithm is suggested for estimating delay *** effectiveness of this method has been demonstrated through simu- *** this method has been used for identifying laboratory CNC system *** delay in this system is due to signal transmission between the CNC and the network.

关键词： Identification time delay systems Gradient algorithm.

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Chinese Physics Letters 2010年第9期27卷 57-60页

作者：郭锋周玉荣张宇 School of Information Engineering Southwest University of Science and Technology Mianyang 621010 School of Information and Electric Engineering Panzhihua University Panzhihua 617000 College of Economics and Management Southwest University of Science and Technology Mianyang 621010

Stochastic resonance in a time-delayed bistable system subject to asymmetric dichotomous noise and multiplicarive and additive white noise is investigated. Using small time delay approximation, we obtain the expression of the signal-to-noise ratio （SNR）. It is found that the SNR is a non-monotonic function of the delayed times, of the amplitude of the input square-wave signal, as well as of the asymmetry of the dichotomous noise. In addition, the SNR varies non-monotonously with the system parameters, with the intensities of the multiplicative and additive noise, as well as with the correlate rate of the dichotomous noise.

关键词： STOCHASTIC processes time delay systems SQUARE waves APPROXIMATION theory SIGNAL-to-noise ratio WHITE noise theory MONOTONIC functions

Effect of time-delay in the Logistic Growth Model Driven by Weak Signal and White Noise

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Chinese Physics Letters 2010年第8期27卷 31-34页

作者：周玉荣 School of Information and Electric Engineering Panzhihua University Panzhihua 617000

Effect of delayed time in the logistic growth model subject to weak periodic signal and correlated multiplicative and additive white noise is investigated. Using small time delay approximation, we obtain the expression of the signal-to-noise ratio （SNR）. It is found that the SNR is non-monotonic functions of the delayed times, the system parameters, the intensities of the multiplicative and additive noise, as well as the correlation strength of the two noises.

关键词： time delay systems FUNCTIONS (Mathematics) MATHEMATICAL models SIGNAL processing WHITE noise theory APPROXIMATION theory SIGNAL-to-noise ratio CORRELATION (Statistics)

A New Quantum Key Distribution Scheme Based on Frequency and time Coding

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Chinese Physics Letters 2010年第9期27卷 12-15页

作者：朱畅华裴昌幸权东晓高晶亮陈南易运晖 State Key Laboratory of Integrated Services Networks Xidian University Xi'an 710071

A new scheme of quantum key distribution （QKD） using frequency and time coding is proposed, in which the security is based on the frequency-time uncertainty relation. In this scheme, the binary information sequence is encoded randomly on either the centrM frequency or the time delay of the optical pulse at the sender. The central frequency of the single photon pulse is set as w1 for bit 0 and set as w2 for bit 1 when frequency coding is selected. However, the single photon pulse is not delayed for bit 0 and is delayed in τ for 1 when time coding is selected. At the receiver, either the frequency or the time delay of the pulse is measured randomly, and the final key is obtained after basis comparison, data reconciliation and privacy amplification. With the proposed method, the effect of the noise in the fiber channel and environment on the QKD system can be reduced effectively.

关键词： QUANTUM theory DISTRIBUTION (Probability theory) CODING theory UNCERTAINTY (Information theory) BINARY system (Mathematics) time delay systems FIBRE Channel (Standard)

Topology Identification of General Dynamical Network with Distributed time delays

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Chinese Physics Letters 2009年第7期26卷 1-4页

作者：吴召艳傅新楚 Department of Mathematics Shanghai University Shanghai 200444

Genera/dynamical networks with distributed time delays are studied. The topology of the networks are viewed as unknown parameters, which need to be identified. Some auxiliary systems （also called the network estimators） are designed to achieve this goal. Both linear feedback control and adaptive strategy are applied in designing these network estimators. Based on linear matrix inequalities and the Lyapunov function method, the sufficient condition for the achievement of topology identification is obtained. This method can also better monitor the switching topology of dynamical networks. Illustrative examples are provided to show the effectiveness of this method.

关键词： SYSTEM identification TOPOLOGY time delay systems FEEDBACK control systems MATRIX inequalities LYAPUNOV functions

time-delay Enhanced Coherence Resonance in a Discrete Neuron with Noises

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Chinese Physics Letters 2014年第8期31卷 8-11页

作者：王参军杨科利屈世显 InstituteofTheoreticalandComputationalPhysics SchoolofPhysicsandInformationTechnologyShaanxiNormalUniversityXi'an710062 NonlinearResearchInstitute BaojiUniversityofArtsandSciencesBaoji721016

Coherence resonance in a discrete excitable neuronal model with noises and time delays is investigated. The effects of the time delays on coherence resonance are revealed in two cases： Gaussian white and Gaussian color noises, respectively. The coefficient of variation of interspike intervals is calculated by numerical simulation. The results show that the coherence resonance is enhanced with the time delay increasing in the weak noises intensity cases, while there is no effect in the large noise intensity. Moreover, the coherence resonance can be held back by the self-correlation time, when the system is driven by a color noise.

关键词： STOCHASTIC resonance RESEARCH time delay systems RESONANCE RANDOM noise theory ADDITIVE white Gaussian noise channels

Range-Gated Laser Stroboscopic Imaging for Night Remote Surveillance

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Chinese Physics Letters 2010年第9期27卷 94-97页

作者：王新伟周燕范松涛何军刘育梁 Optoelectronic System Laboratory Institute of Semiconductors Chinese Academy of Sciences Beijing 100083

For night remote surveillance, we present a method, the range-gated laser stroboscopic imaging（RGLSI）, which uses a new kind of time delay integration mode to integrate target signals so that night remote surveillance can be realized by a low-energy illuminated laser. The time delay integration in this method has no influence on the video frame rate. Compared with the traditional range-gated laser imaging, RGLSI can reduce scintillation and target speckle effects and significantly improve the image signal-to-noise ratio analyzed. Even under low light level and low visibility conditions, the RGLSI system can effectively work. In a preliminary experiment, we have detected and recognized a railway bridge one kilometer away under a visibility of six kilometers, when the effective illuminated energy is 29.5μl.

关键词： STROBOSCOPES time delay systems DIGITAL image processing SIGNAL-to-noise ratio IMAGING systems REMOTE sensing