Chua电路全局同步的新结果

Some new results on global exponential synchronization and global synchronization for Chua0s circuit are derived by means of Lyapunov functions and some other mathematic methods, which improve the existing results in the literatures. A strict and complete proof of the result is also given as a complement to the relevant literature where the proof was incomplete. The paper offers some new approaches for studying chaos synchronization for Chua0s circuit.     

Exponential synchronization of impulsive complex networks with output coupling

This paper proposes a new impulsive complex delayed dynamical network model with output coupling, which is totally different from some existing network models. Then, by employing impulsive delay differential inequalities, some sufficient conditions are obtained to guarantee the global exponential state synchronization and output synchronization of the impulsive complex delayed dynamical network. Finally, two numerical examples are given to demonstrate the effectiveness of the obtained results.     

Pinning control of a generalized complex dynamical network model

This paper investigates the local and global synchronization of a generalized complex dynamical network model with constant and delayed coupling. Without assuming symmetry of the couplings, we proved that a single controller can pin the generalized complex network to a homogenous solution. Some previous synchronization results are generalized. In this paper, we first discuss how to pin an array of delayed neural networks to the synchronous solution by adding only one controller. Next, by using the Lyapunov functional method, some sufficient conditions are derived for the local and global synchronization of the coupled systems. The obtained results are expressed in terms of LMIs, which can be efficiently checked by the Matlab LMI toolbox. Finally, an example is given to illustrate the theoretical results.     

Some new criteria for lag synchronization of chaotic Lur＇e systems by replacing variables control

Some new criteria for the chaotic lag synchromzation are proposed. At first, lag synchronization scheme for identical master-slave Lur‘e systems by replacing variables control and the relevant error system are given, and the relations between absolute stability of the error system and the chaotic lag synchromzation are described. Then. based on a quadratic Lyapunov function, two new Lur‘e criteria for the above chaotic lag synchronization are proved. Four corresponding frequency domain criteria are further derived by means of Meyer-Kalman-Yacubovia Lemma. These frequency domain criteria are apphed to analyze the lag synchromzation of general master-slave Chua‘s circuits so that some ranges of the parameters in which the master-slave Chua‘s circuits achieve chaotic lag synchronization by replacing single-variable control are attained. Finally, some examples are given to verify the theoretical results.     

Adaptive synchronization of different kinds of chaotic neural networks

The purpose of the paper is to present an adaptive control method for the synchronization of different classes of chaotic neural networks. A new sufficient condition for the global synchronization of two kinds of chaotic neural networks is derived. The proposed control method is efficient for implementing the synchronization when the parameters of the drive system are different from those of the response system. A numerical example is used to demonstrate the validity of the proposed method and the obtained result.     

Application research on the chaos synchro-nization self-maintenance characteristic to secret communication

Chua's circuit, which is improved to integrate conveniently, is presented. A drive-response chaotic synchronization system is constructed, which possesses a certain stability, resisting-disturbance, and so on. By means of research, it can be concluded that the chaotic synchronization system is provided with the character- istic of chaos synchronization self-maintenance. Utilizing the characteristic, the critical problem of how to simultaneously transmit the controlling signal of chaotic synchronization and the secret signal at a channel can be solved, and that a prac- tical experiment validates the method; as a result, the research in the paper pro- vides the foundation of putting chaos into practice application to secret commu- nication.     

New results of study on generating multiple-scroll chaotic attractors

We present a new method for generating multiple-scroll attractors. By constructing a piece-wise-linear odd function as the driving-point characteristic of Chua's diode with multiple breakpoints, and finding a recurrence formula for determining equilibrium point voltages and breakpoint voltages, we can calculate the voltages of all the equilibrium points and breakpoints, and the multiple-scroll chaotic attractors can be obtained. This method is based on Shil'nikov theorem and the cell model of chaotic attractors. The theoretical calculations are in good agreement with computer simulations and hardware experimental results. Compared with the results reported by Suykens, our method has some advantages that much more scrolls can be obtained, the scrolls are uniform in size, and a general recurrence formula for generating attractors with any number of scrolls is given. Furthermore, the observation of attractors with a maximum of 11-21 uniform scrolls obtained by hardware experiment and computer simulation, r     

Two New Strategies for Developing Loop Invariants and Their Applications

The loop invariants take a very important role in the design,proof and derivation of the algorithmic program.We point out the limitations of the taditional standard strategy for developing loop invariants.and propose two new strategies for proving the existing algorithmic program and developing new ones.The strategies ure recurrence as vehicle and integrate some effective methods of designing algorithms,e.g.Dynamic Porgramming,Greedy and Divide-Conquer,into the recurrence relation of problem solving sequence.This lets us get straightforward an approach for solving a variety of complicated problems,and makes the standard proof and formal derivation of their algorithmic programs possible.We show the method and advantages of applying the strategies with several typical nontivial examples.     

Robust decentralized adaptive stabilization for a class of interconnected systems

The robust decentralized adaptive output-feedback stabilization for a class of interconnected systems with static and dynamic interconnections by using the MT-filters and backstepping design method is studied. By introducing a new filtered tramfomnation, the adaptive laws were derived for measurement. Under the assurnption of the nonlinear growth conditions imposed on the nonlinear interconnections and by constructing the error system and using a new proof method, the global stability of the closed-loop system was effectively analyzed, and the exponential convergence of all the signals except for parameter estimates were guaranteed.     

Path Sensitization

For different delay models,the concept of sensitization can be very different.Traditonal concepts of sensitization cannot precisely describe circuit behavior when the input vectors change very fast.Using Boolean process aporoach,this paper presents a new definition of sensitization for arbitrary input waveforms.By this new concept it is found that if the inputs of a combinational circuit can change at any time,and each gate‘s delay varies within an interval (bounded gate delay model),then every path,which is not necessarily a single topological path,is sensitizable.From the experimental results it can be seen that,all nonsensitizable paths for traditional concepts actually can propagate transitions along them for some input waveforms.However,specified time between input transitions(STBIT) and minimum permissible pulse width(ε）are two major factors to make some paths non-sensitizable.     

基于蔡氏电路的混沌同步的研究

该文采用研究混沌连续时间系统的同步方法，基于系统的稳定性准则，分析了蔡氏电路的混沌同步问题，即用同步误差的线性系统的稳定性分析来保证混沌的同步。通过系统的线性项和非线性项的适当分离，使系统的雅可比矩阵的全部特征值为负值，此时响应系统与驱动系统的状态变量之间，存在一个与初值有关的误差，无论初始同步误差多大。都能使同步误差e（t）最终趋于稳定，从而实现新、旧系统的完全同步。运用该方法对蔡氏电路进行计算机仿真实验，得到的仿真结果和分析相符，证明了该方法在研究非线性电路方面是简单有效的，为今后研究类似问题提出了新思路。     

复合系统的混沌同步控制及在半双工保密通信中的应用

在一定条件下,对多个工作站的复合混沌的混沌同步提出了控制设计方法,并把结果应用到半双工保密通信中,仿真实例利用了Ｃｈｕａ‘ｓ电路。     

脉冲同步在数字保密通信中的应用

首先给出了蔡氏混沌电路的脉冲同步方法，同时给出了其同步的渐进稳定条件，最后构造了一个基于脉冲同步的数字保密通信系统，系统实验表明应用脉冲同步具有高保密性和鲁棒性。     

新控制器实现不同Chua系统的同步控制

针对实际中两Chua混沌系统同步可能遇到的问题,即不同混沌状态两相同结构的混沌系统以及不同结构的Chua系统之间的同步问题,提出了一种新的控制器。利用Lya-punov稳定性理论,对新控制器控制两系统同步误差的稳定性进行了分析和证明。最后,利用Matlab进行了大量的计算机数值仿真实验,研究了5涡与3涡,5涡与1涡,5涡与非混沌态及不同结构Chua系统之间的同步。数值仿真实验的结果证实了该控制器的有效性。     

基于鲁棒控制的不确定性混沌系统的同步化

研究了两个不确定性混沌系统的同步化问题．由于受到外界因素的干扰，混沌系统的参数会在一定范围内变化，从而导致其不确定性的产生．以两个相互耦合的不确定性混沌系统为研究模型，基于鲁棒控制，提出了同步方案．采用Lyapunov-Krasovskii稳定性理论和线性矩阵不等式（LMI），严格证明了该方案的有效性．同时，给出了以Chuas电路为例的数值仿真，其结果与理论推导相一致．     

时分复用在混沌保密通信中的应用研究

给出了一种便于集成的改进型Chua电路,构造出一种具有一定鲁棒性、抗干扰等特性的驱动一响应式混沌同步系统,研究发现此混沌同步系统具有自保持特性,并给出研究结果;利用此特性,根据时分复用原理解决了目前如何同时在同一信道中传输混沌同步控制信号和密文信号的关键性问题,实验证明了此方案的可行性,为混沌在保密通信中的实际应用奠定了基础。     

主从Lur’e系统混沌同步的时滞输出反馈控制

该文讨论了主从Lur’e系统之间混沌同步的输出反馈控制问题,利用Lyapunov方法和矩阵不等式技巧,得到了一个依赖于时滞的混沌同步的充分条件,该条件易于用LMI(线性矩阵不等式)方法进行验证,并可对最大允许时滞进行估计,最后结合Chua’s电路进行了数值模拟。