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Adaptive control of a class of nonlinear time-varying systems with multiple models

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Control Theory and Technology 2016年第4期14卷 323-334页

作者： Koshy GEORGE Karpagavalli SUBRAMANIAN PES Centre for Intelligent systems department of telecommunication Engineering PES Institute of Technology Bangalore India PES Centre for Intelligent systems department of Electronics and Communication Engineering PES University Bangalore India

The adaptive control of nonlinear systems that are linear in the unknown but time-varying parameters are treated in this paper. Since satisfactory transient performance is an important factor, multiple models are required as these parameters change abruptly in the parameter space. In this paper we consider both the multiple models with switching and tuning methodology as well as multiple models with second level adaptation for this class of systems. We demonstrate that the latter approach is better than the former.

关键词： Nonlinear time-varying systems adaptive control multiple models

Introducing robustness in model predictive control with multiple models and switching

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Control Theory and Technology 2014年第3期12卷 284-303页

作者： Sachin PRABHU Koshy GEORG department of telecommunication Engineering PES Institute of Technology Bangalore 560085 India PES Centre for Intelligent systems Bangalore 560085 IndiaE

Model predictive control is model-based. Therefore, the procedure is inherently not robust to modelling uncertainties. Further, a crucial design parameter is the prediction horizon. Only offline procedures to estimate an upper bound of the optimal value of this parameter are available. These procedures are computationally intensive and model-based. Besides, a single choice of this horizon is perhaps not the best option at all time instants. This is especially true when the control objective is to track desired trajectories. In this paper, we resolve the issue by a time-varying horizon achieved by switching between multiple model-predictive controllers. The stability of the overall system is discussed. In addition, an introduction of multiple models to handle modelling uncertainties makes the overall system robust. The improvement in performance is demonstrated through several examples.

关键词： Receding horizon control Time-varying horizon Multiple models Switching Tracking Robustness

Molecular dynamic simulation of the thermodynamic and kinetic properties of nucleotide base pair

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Chinese Physics B 2017年第12期26卷 1-6页

作者：王宇杰王珍王晏莉张文炳 department of Physics Wuhan University department of Physics and telecommunication Engineering Zhoukou Normal University

A nucleotide base pair is the basic unit of RNA structures. Understanding the thermodynamic and kinetic properties of the closing and opening of a base pair is vital for quantitative understanding the biological functions of many RNA molecules. Due to the fast transition rate, it is difficult to directly observe opening and closing of single nucleic acid base pair in experiments. This review will provide a brief summary of the studies about the thermodynamic and kinetic properties of a base pair opening and closing by using molecular dynamic simulation methods.

关键词： thermodynamics kinetics molecular dynamic simulation

Adaptive Three-phase Estimation of Sequence Components and Frequency Using H∞ Filter Based on Sparse Model

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Journal of Modern Power systems and Clean Energy 2020年第5期8卷 981-990页

作者： Umamani Subudhi Harish Kumar Sahoo Sanjeev Kumar Mishra department of Electronics and telecommunication Engineering Indian Institute of Information Technology(IIIT)BhubaneshwarIndia department of Electronics and telecommunication Engineering Veer Surendra Sai University of Tecnology(Burla)SambalpurIndia

The estimation of sequence or symmetrical components and frequency in three-phase unbalanced power system is of great importance for protection and *** paper proposes a new H∞filter based on sparse model to track the sequence components and the frequency of three-phase unbalanced power *** inclusion of sparsity improves the error convergence behavior of estimation model and hence short-duration non-stationary PQ events can easily be tracked in the time *** proposed model is developed using l1 norm penalty in the cost function of H∞filter,which is quite suitable for estimation across all the three phases of an unbalanced *** model uses real state space modeling across three phases to estimate amplitude and phase parameters of sequence ***,frequency estimation uses complex state space modeling and Clarke transformation generates a complex measurement signal from the unbalanced three-phase *** state vector used for frequency estimation consists of two state *** proposed sparse model is tested using distorted three-phase signals from IEEE-1159-PQE database and the data generated from experimental laboratory *** analysis of absolute and mean square error is presented to validate the performance of the proposed model.

关键词： Sequence component Clarke transformation H∞filter state space model

A Novel Quarter-Circular Arc Multi-Direction Piezoelectric VEH and Its Theoretical Model

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Chinese Journal of Electronics 2021年第1期30卷 185-191页

作者： ZHU Yucheng HU Jiayang BAI Yunshan ZHAO Jiang JI Xincun WANG Debo Nanjing University of Posts and telecommunication department of Physics Army Logistics University of PLA

A quarter-circular arc piezoelectric Vibration energy harvester(VEH) based on nonlinear geometry is proposed with both bending moment and torque deformation mode, so it can effectively absorb multi-directional vibration at the same resonance frequency. The theoretical model of quarter-circular arc piezoelectric VEH is established to study the resonance frequency and the output voltage. In order to demonstrate multi-directional performance of the quarter-circular arc VEH, the stress distribution is compared with that of the traditional piezoelectric VEH in multi-direction vibration, and the output voltage of the circular arc piezoelectric VEH are relatively increased 267.26% in X-direction, 463.18% in Ydirection, and 17.24% in Z-direction. The external load is equipped in circuit to measure output power, whose matching resistance is around 21 k?, and the maximum output powers are 7.57 m W in X-direction, 2.39 m W in Y-direction, and 9.93 m W in Z-direction.

关键词： multidirectional vibration quarter-circular arc piezoelectric VEH multidirection vibration bending moment vibrations quarter-circular arc VEH power 7.57 mW piezoelectric VEH resonance frequency nonlinear equations quarter-circular arc multidirection piezoelectric VEH quarter-circular arc piezoelectric vibration energy harvester power 9.93 mW nonlinear geometry torque deformation mode piezoelectric transducers energy harvesting multidirectional performance power 2.39 mW

Gait Recognition by Cross Wavelet Transform and Graph Model

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IEEE/CAA Journal of Automatica Sinica 2018年第3期5卷 718-726页

作者： Sagar Arun More Pramod Jagan Deore department of Electronics and telecommunication Engineering R.C.Patel Institute of Technology

In this paper, a multi-view gait based human recognition system using the fusion of two kinds of features is *** use cross wavelet transform to extract dynamic feature and bipartite graph model to extract static feature which are coefficients of quadrature mirror filter(QMF)-graph wavelet filter bank. Feature fusion is done after normalization. For normalization of features, min-max rule is used and mean-variance method is used to find weights for normalized features. Euclidean distance between each feature vector and center of the cluster which is obtained by k-means clustering is used as similarity measure in Bayesian framework. Experiments performed on widely used CASIA B gait database show that, the fusion of these two feature sets preserve discriminant information. We report 99.90 % average recognition rate.

关键词： Binary sequences feature extraction identification of persons linear discriminant analysis(LDA)

SEQUENCES WITH CONTROLLABLE LINEAR COMPLEXITY PROFILE

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Chinese Science Bulletin 1990年第10期35卷 867-869页

作者：林须端蔡长年 department of telecommunication Engineering Beijing University of Post and Telecommunication Beijing 100088 PRC

Ⅰ. INTRODUCTIONLet s=（S0, s1, s2,…） be an infinite sequence on GF（q）, sn=(s0, s1,…,sn-1). The linear complexity of the sequence sn is defined to be Ln（s）=min{1: sj=-sum from i=1 to l(CiSj-1), j=1, 1+1,…, n-1, c1,c2,…,c1∈GF（q）}, i.e. Ln（s）is the smallest nonnegative integer L such that there exist the constants c1, c2,…,c1 for

关键词： pseudorandom sequence stream cipher information theory.

Dynamics of super-quantum discord and direct control with weak measurement in open quantum system

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Chinese Physics B 2015年第12期24卷 209-214页

作者：嵇英华 department of Physics Jiangxi Normal University Key Laboratory of Photoelectronics and telecommunication of Jiangxi Province

Super-quantum discord（SQD） with weak measurement is regarded as a kind of quantum correlation in quantum information processing. We compare and analyze the dynamical evolutions of SQD, quantum discord（QD）, and quantum entanglement（QE） between two qubits in the correlated dephasing environmental model. The results indicate that（i） owing to the much smaller influence of weak measurement on the coherence of the system than that of von Neumann projection measurement, SQD with weak measurement is larger than QD, and（ii） dynamical evolution of QD or QE monotonically goes to zero with time, while SQD monotonically tends to a stable value and a freezing phenomenon occurs. The stable value after freezing mainly depends on the measurement strength and the purity of the initial quantum state.

关键词： super-quantum discord(SQD) weak measurement control

Image enhancement via MMSE estimation of Gaussian scale mixture with Maxwell density in AWGN

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Journal of Innovative Optical Health Sciences 2016年第2期9卷 86-93页

作者： Pichid Kittisuwan Faculty of Engineering department of telecommunication Engineering Rajamangala University of Technology(Ratanakosin)Nakhonpathom Thailand

In optical techniques,noise signal is a classical problem in medical image ***,there has been considerable interest in using the wavelet transform with Bayesian estimation as a powerful tool for recovering image from noisy *** wavelet domain,if Bayesian estimator is used for denoising problem,the solution requires a prior knowledge about the distribution of wavelet ***,wavelet coeffcients might be better modeled by super Gaussian *** super Gaussian density can be generated by Gaussian scale mixture(GSM).So,we present new minimum mean square error(MMSE)estimator for spherically-contoured GSM with Maxwell distribution in additive white Gaussian noise(AWGN).We compare our proposed method to current state-of-the-art method applied on standard test image and we quantify achieved performance improvement.

关键词： Gaussian scale mixture minimum mean square error estimation image denoising wavelet transforms