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synchronization of Coupled Neurons Controlled by a Pacemaker

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Chinese Physics Letters 2011年第1期28卷 43-46页

作者： LI Mei-Sheng ZHANG Hong-Hui ZHAO Yong SHI Xia LMIB and School of Mathematics and System Sciences Beihang University Beijing 100191 Department of Dynamics and Control Beihang University Beijing 100191 School of Science Beijing University of Posts and Telecommunications Beijing 100876

We investigate synchronization of Hindmarsh Ftose neurons with gap junctions under the control of a pacemaker. In a ring Hindmarsh-Rose neuronal network, the coupled neurons with the pacemaker can occur in synchronization more easily than those without the pacemaker. Furthermore, the pacemaker can induce phase synchronization or nearly-complete synchronization of nonidentical neurons. This synchronization can occur more easily when time delay is considered. Theses results can be helpful to understand the activities of the real neuronal system.

关键词： Rosa synchronization

Fast frequency relocking for synchronization enhanced resonant accelerometer

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Microsystems & Nanoengineering 2022年第5期8卷 53-60页

作者： Liu Xu Yonghong Qi Zhuangde Jiang Xueyong Wei State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong UniversityXi’anShaanxi 710049China

synchronization,as a unique phenomenon,has been extensively studied in biology,chaotic systems,nonlinear dynamics,quantum information,and other fields.Benefiting from the characteristics of frequency amplification,noise suppression,and stability improvement,synchronization has been gradually applied in sensing,communication,time keeping,and other applications.In the sensing field,synchronization provides a new strategy to improve the performance of sensors.However,the performance improvement is only effective within the synchronization range,and the narrow synchronization range has become a great challenge for the wide application of synchronizationenhanced sensing mechanism.Here,we propose a frequency automatic tracking system(FATS)to widen the synchronization range and track the periodic acceleration signals by adjusting the frequency of the readout oscillator in real time.In addition,a high-precision frequency measurement system and fast response control system based on FPGA(Field Programmable Gate Array)are built,and the tracking performance of the FATS for static and dynamic external signals is analyzed to obtain the optimal control parameters.Experimental results show that the proposed automatic tracking system is capable of static acceleration measurement,the synchronization range can be expanded to 975 Hz,and the relocking time is shortened to 93.4 ms at best.By selecting the optimal PID parameters,we achieve a faster relocking time to meet the requirements of low-frequency vibration measurements,such as seismic detection and tidal monitoring.

关键词： synchronization locking acceleration

synchronization dynamics of phase oscillators with generic adaptive coupling

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Communications in Theoretical Physics 2023年第4期75卷 114-122页

作者： Xin Jin Yong-Gang Wu Hua-Ping Lü Can Xu School of Physics and Electronic Engineering Jiangsu Normal UniversityXuzhou 221116China School of Mathematical Sciences Huaqiao UniversityQuanzhou 362021China Institute of Systems Science and College of Information Science and Engineering Huaqiao UniversityXiamen 361021China

Adaptive coupling schemes among interacting elements are ubiquitous in real systems ranging from physics and chemistry to neuroscience and have attracted much attention in recent years.Here,we extend the Kuramoto model by considering a particular adaptive scheme in a system of globally coupled oscillators.The homogeneous coupling is correlated with the global coherence of the population that is weighted by the generic nonlinear feedback function of the amplitude of the order parameter.The studied model is analytically tractable that generalizes the theory of Kuramoto for synchronization transition.We develop a mean-field theory by establishing the self-consistent equation describing the stationary dynamics in the thermodynamic limit.Importantly,the Landau damping effect,which turns out to be far more generic,is revealed in the framework of the linear stability analysis of the resonant pole theory.Furthermore,the relaxation rate of the order parameter in the subcritical region is obtained from a universal formula.Our study can deepen the understanding of synchronization transitions and other related collective dynamics in networked oscillators with adaptive interaction schemes.

关键词： synchronization complex system coupled oscillators phase transition

synchronization of Robot Manipulators Actuated By Induction Motors with Velocity Estimator

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Computer Modeling in Engineering & Sciences 2019年第11期121卷 609-630页

作者： Felipe J.Torres Gerardo V.Guerrero Carlos D.García Ricardo Zavala-Yoe Mario A.García Adolfo R.López University of Guanajuato Division of Engineering Campus Irapuato-SalamancaCarretera Salamanca-Valle de Santiago km 3.5+1.8GuanajuatoSalamanca36885México National Technological of Mexico/National Center of Research and Technological Development Av.Palmira S/N colonia PalmiraMorelosCuernavaca62490México School of Engineering and Sciences Monterrey TechnologicalPuente 222 Ejidos de HuipulcoCiudad de México14380México Superior Technological Institute of Irapuato Carretera Irapuato-Silao km 12.5GuanajuatoIrapuato36821México

A complete modeling(including the actuator dynamics)of a robot manipulator that uses three-phase induction motors is presented in this paper.A control scheme is designed to synchronize robot manipulators actuated by induction motors under a masterslave scheme in the case where the joint velocity of the slave robots is estimated.All of the research on the synchronization of robot manipulators assumes the use of ideal actuators to drive the joints;for that reason,in this work,a three-phase induction motor is considered to be a direct-drive actuator for each joint.An entire model of the mated system is obtained by a combination of the dynamics of the induction motor and robot manipulator.Thus,the synchronization control algorithm for a master-slave scheme in both the joint space and workspace of robot manipulators driven by induction motors is developed.An observer based on the entire model is proposed to estimate the joint velocity of the slave robot manipulators.Through the Lyapunov criterion,a stability analysis of the synchronization control with a velocity estimator is detailed.The analytical results show the synchronization and estimation errors are globally,uniformly,and ultimately bounded.Simulations with multiple robots demonstrate the performance of the proposed control algorithm.

关键词： synchronization robot manipulator induction motor Lyapunov stability observer based on the model

synchronization of Radar Observations with Multi-Scale Storm Tracking

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Advances in Atmospheric Sciences 2009年第1期26卷 78-86页

作者：杨洪平 Jian ZHANG Carrie LANGSTON Wuhan Institute of Heavy Rain China Meteorological Administration Wuhan 430074 Cooperative Institute for Mesoscale Meteorological Studies The University of Oklahoma and NOAA/OAR National Severe Storms Laboratory Norman O.K. U.S.A

The 3-D radar reflectivity data has become increasingly important for use in data assimilation towards convective scale numerical weather prediction as well as next generation precipitation estimation. Typically, reflectivity data from multiple radars are objectively analyzed and mosaiced onto a regional 3-D Cartesian grid prior to being assimilated into the models. One multi-radar observations is the synchronization of all of the scientific issues associated with the mosaic of the observations. Since radar data is usually rapidly updated （-every 5-10 min）, it is common in current multi-radar mosaic techniques to combine multiple radar＇ observations within a time window by assunfing that the storms are steady within the window. The assumption holds well for slow evolving precipitation systems, but for fast evolving convective storms, this assumption may be violated and the mosaic of radar observations at different times may result in inaccurate storm structure depictions. This study investigates the impact of synchronization on storm structures in multiple radar data analyses using a multi-scale storm tracking algorithm.

关键词： synchronization radar multi-scale storm tracking

synchronization Transition of Time Delayed Complex Dynamical Networks with Discontinuous Coupling

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Communications in Theoretical Physics 2017年第1期67卷 54-60页

作者：孙永征李望赵东华 School of Mathematics China University of Mining and TechnologyXuzhou School of Mathematical Sciences Fudan University

This paper investigates the synchronization of time delayed complex dynamical networks with periodical on-off coupling. Both the theoretical and numerical results show that, in spite of time delays and on-off coupling, two networks may synchronize if the coupling strength and the on-off rate are large enough. It is shown that, for undirected and strongly connected networks, the upper bound of time delays for synchronization is a decreasing function of the absolute value of the minimum eigenvalue of the adjacency matrix. The theoretical analysis confirms the numerical results and provides a better understanding of the influence of time delays and on-off coupling on the synchronization transition. The influence of random delays on the synchronization is also discussed.

关键词： complex dynamical network synchronization time delay on-off coupling

synchronization of MIMO OFDM systems by perfect complete generalized complementary orthogonal loosely synchronous code groups

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 1-7页

作者： WANG Jian YANG Xun LI Dao-ben School of Information Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China School of Information Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This article proposes a time/frequency synchronization algorithm in the multiple input multiple output （MIMO） systems, in which the perfect complete generalized complementary orthogonal loosely synchronous code groups are used as the synchronization sequence. The synchronization algorithm is divided into four stages： 1） synchronization in time domain by signal autocorrelation; 2） synchronization in frequency domain by fast Fourier transform （FFT）; 3） multipath dissociation using coherent detection and fine time synchronization; 4） fine frequency offset estimation by phase rotation. As per the perfect complete generalized complementary orthogonal loosely synchronous code groups, the cross-correlation and out-of-phase auto-correlation for any relative shift between any two codes is always zero. This ideal property makes the time/frequency synchronization algorithm simple and efficient. The simulation results show that even in the multipath fast fading channel with low signal noise ratio （SNR）, the MIMO system can get synchronized both in the time domain and frequency domain with high stability and reliability.

关键词： MIMO OFDM synchronization complementary orthogonal code loosely synchronous （LS） code

synchronization OF SINGULAR MARKOVIAN JUMPING NEUTRAL COMPLEX DYNAMICAL NETWORKS WITH TIME-VARYING DELAYS VIA PINNING CONTROL

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Acta Mathematica Scientia 2020年第3期40卷 863-886页

作者： K.S.ANAND J.YOGAMBIGAI G.A.HARISH BABU M.SYED ALI S.PADMANABHAN APS College of Engineering Bangalore 560082India MMES College of Arts and Science MelvisharamTamilnaduIndia Reva Institute of Technology and Management Bengaluru-560064 Department of Mathematics Thiruvalluvar UniversityVelloreTamilnadu 632115India RNS Institute of Technology ChannasandraBangalore 560098India

This article discusses the synchronization problem of singular neutral complex dynamical networks(SNCDN)with distributed delay and Markovian jump parameters via pinning control.Pinning control strategies are designed to make the singular neutral complex networks synchronized.Some delay-dependent synchronization criteria are derived in the form of linear matrix inequalities based on a modified Lyapunov-Krasovskii functional approach.By applying the Lyapunov stability theory,Jensen's inequality,Schur complement,and linear matrix inequality technique,some new delay-dependent conditions are derived to guarantee the stability of the system.Finally,numerical examples are presented to illustrate the effectiveness of the obtained results.

关键词： Singular complex networks synchronization Lyapunov-krasovski method markovian jump pinning control linear matrix inequality

synchronization-Oriented Placement and Retrieval Strategies for Delay-Sensitive Media Streams

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Journal of Computer Science & Technology 1996年第2期11卷 150-160页

作者：赵彧何志钧石教英 StateKeyLaboratoryofCAD＆CG ArtificialIntelligenceInstituteZhejiangUniversity Hangzhou310027

Multimedia data include text, image, audio and video, etc. Recent deve-lopments and advances in the areas of mass storage technology and high speed networks make it feasible for multimedia computing systems to offer services such as multimedia e-mail, teleconferencing and various vivid games. The stor-age and retrieval of multimedia data are two of the most important technologies in the future multimedia systems. This paper analyzes the synchronization re-quirements of the delay-sensitive media streams, classifies the synchronization hierarchically and proposes several effective strategies for the intra-media and inter-media data placement problems.

关键词： Multimedia computing system synchronization storage retrieval