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提出利用符号函数产生3涡卷混沌吸引子的方法,进行基本的混沌动力学分析,给出最大李雅普诺夫指数、功率谱、庞加莱映射,并基于李雅普诺夫稳定性理论,研究了两个3涡卷混沌吸引子的单向耦合同步的问题,给出3涡卷混沌吸引子产生及其同步的数值模拟结果. 相似文献
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基于通用忆阻器模型,设计了一个广义忆阻器并将其引入混沌系统,构建了一个新的四阶忆阻超混沌系统,探究了其动力学特性。首先对新型四阶忆阻超混沌系统的相图、耗散性、李雅普诺夫指数、稳定性等特性进行分析,发现其存在无穷多平衡点集,且比原系统有更高的维度、混沌性以及复杂度。通过进一步分析其动力学现象,发现随着参数和初值的变化,其分岔特性和李雅普诺夫指数反映出多吸引子共存等现象。最后通过数值仿真与模拟电路仿真的相图对比,验证忆阻混沌系统电路的可行性。新系统有着更复杂的非线性行为,因此具有更高的研究价值,同时为忆阻混沌电路的实际应用奠定了基础。 相似文献
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通过对一个注入激光系统的分岔图、李雅普诺夫(Lyapunov)指数谱、功率谱和相轨道的数值计算与分析,得到了系统出现不动点、极限环、混沌、超混沌的参数区间。为进一步研究该系统在混沌和起混沌状态下的统计性质奠定了基础。 相似文献
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当非线性系统的参数发生变化时,可能就会出现混沌.文中首先提出了目前对混沌现象的判别问题,分析了各方法的优缺点.然后提出了一种新的计算李雅普诺夫(Lyapunov)指数的方法来确定动力学系统方程出现的混沌等模式,给出了判别条件.同时讨论了如何通过计算机来实现李雅普诺夫指数的计算并给出了程序框图.研究表明,该方法在理论上可靠,实施容易,克服了已有各种方法的不足,便于做计算机的自动推导辨识,具有重要的实际应用意义和可行性. 相似文献
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该文提出一个新的平方混沌类,计算了混沌类的李雅普诺夫指数,并对混沌类中结构III所表现出的环面破裂产生混沌和倍周期分岔产生混沌的现象进行了初步的研究,在同一个系统中可以观察到环面破裂和倍周期分岔两种不同的通向混沌的路线,这尚属首次报道。 相似文献
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基于对低信噪比下状态空间重构问题的研究,并结合重构信号强度(RSS)方法分析重构窗口,得到了明显改善信噪比的重构状态空间, 低信噪比下,利用改进后的最大李雅普诺夫指数的算法有效地估计Lorenz等模型的最大李雅普诺夫指数,这种方法可能成为识别淹没在噪声中的混珠有效途径。 相似文献
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针对混沌动力学系统建模困难,控制不易实现,存在干扰等特点,在附加动量法的自适应BP网络的基础上,研究了混沌动力学系统的学习控制策略。构建了混沌动力学系统的NN模型和NN控制器,对混沌系统在学习的同时施加控制,仿真实验结果表明,该控制策略具有鲁棒性强,有良好的适应性,网络参数训练时间短等优点。 相似文献
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1 IntroductionSince 1 990 ,chaoticsynchronization[1~ 4] andchaoticcontrolling[5~6] havereceivedagreatdealofattention[7~1 1 ] ,andchaoticsynchronizationisaphenomenonofinterestinfieldsfromelectronicstocommunication[1 2 ] ,andfrombiophysicstoneuro science[1 3] .Ifchaoticsync… 相似文献
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Guo-Ping Jiang Guanrong Chen Wallace Kit-Sang Tang 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2004,51(6):281-288
In this paper, a simple control method is proposed for stabilizing unstable equilibria of two typical classes of chaotic systems. For piecewise-linear chaotic systems, such as Chua's circuit, the control parameters can be selected via the pole placement technique from the linear control theory. For general nonlinear chaotic systems with continuously differentiable nonlinearities, particularly polynomial chaotic systems such as the Ro/spl uml/ssler system, Lorenz system, Chen's system, and the modified Chua's circuit with cubic nonlinearity, the control parameters can be chosen according to the pole placement technique and some additional theories of nonlinear ordinary differential equations. The criteria for the design of the control parameters are also investigated. This method is demonstrated to be highly robust against system parametric variations. To verify the effectiveness of the method, it is applied to both the original and the modified chaotic Chua's circuits, where satisfactory control performance is observed in simulations. 相似文献
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提出了一种基于混沌蚂蚁群算法的控制系统辨识方法,这种方法在给定控制系统数学模型的条件下,将控制系统的参数辨识问题转化为参数的寻优问题,之后利用混沌蚂蚁群算法的全局优化搜索能力对问题进行求解.以典型控制系统为例进行了计算机仿真,实验结果表明,使用混沌蚂蚁群算法可以得到很好的参数估计结果. 相似文献
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基于联合混沌系统的保密通信方法研究 总被引:1,自引:1,他引:0
提出了利用离散混沌系统联合加密来实现保密通信的方法。引用著名的Henon和Lorenz混沌系统作为仿真实验证明了其可行性,混沌系统均采用backstepping和dead-beat同步设计方案,以快速达到同步,理论分析证明,此种方法不仅是可行的,且与非联合混沌系数相比,加强了保密性。混沌屏蔽技术仿真结果也证明,该系统不仅实现简单,容易控制,而且增强了整个系统的保密性能。 相似文献
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利用非线性函数控制的混沌异结构同步 总被引:1,自引:1,他引:0
万志超 《微电子学与计算机》2008,25(4):52-55
研究了利用非线性函数控制的混沌异结构同步问题.基于Lyapunov稳定性理论,设计了非线性控制函数,使得同步误差系统的Lyapunov函数的形式为V(e)=eTPe(P为正定矩阵),根据数学公式推导,理论证明了该方法可以实现不同混沌系统之间的异结构同步.数值模拟进一步验证了所提出方案的有效性. 相似文献
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In this paper, it is proposed a method for controlling chaotic systems; where the main goal is to obtain a periodic behaviour for a chaotic system. In our approach, the system to control is considered as a black-box, and therefore it is not necessary to know a mathematical model of the system, only experimental measurements are used. Our method employs pulses with adjustable amplitude and width, and it is implemented in discrete time. In order to generate pulses control, a variable Poincaré section is used; which is computed on-line using a moving average sampling signal. Measurement noise is considered too, by means of an additional controller parameter (hold-off time), resulting that controller tuning is made using four parameters: proportional gain, sampling time, pulse width and hold-off time. In order to test the proposed method, computer simulations with several representative chaotic systems (Lorenz, Chua, Chen, Colpitts and others) are carried out and satisfactory results are obtained. 相似文献
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In recent years, various chaotic systems have been introduced in literature to be used in different branches of science. In the field of secure chaotic communication, more complex chaotic systems are proposed, such as high dimensional (4D, 5D), multi-scroll, surface equilibrium point, to enhance communication security level. In this study, a chaotic system owning logic element is used for increasing the level of security of chaotic communication system, which has not been previously implemented for this purpose in the literature. The used chaotic system includes signum functions, maximum function and absolute operation term. Also, there are analog devices and digital device in the electronic circuit of this chaotic system. These properties increase the complexity of the chaotic system and the security level. Sliding mode control method is preferred for the synchronization part of the secure communication. In this regard, numerical analysis and electronic circuit design of the secure chaotic communication system by using the chaotic system owning logic element have been performed successfully. 相似文献
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Department of Electronic Information Zhejiang Ocean University Zhoushan ChinaLIU Yu-liang ZHU Jie DING Da-wei Department of Electronic Engineering Shanghai Jiaotong University Shanghai China 《中国邮电高校学报(英文版)》2007,14(2):103-105
By the control method independent of system parameters, synchronization of two Chen chaotic systems with identical, but uncertain parameters is discussed in this article. Based on Lyapunov’s theorem, an adaptive controller and the parameters estimate update law are derived to make the solution of the error dynamical equation converge at the point E(0, 0, 0) with a quick speed, that is, the states of two Chen chaotic systems can be asymptotically synchronized. Numerical simulations verify the effectiveness and the adaptivity to the variation of Chen system parameters. 相似文献