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排序方式: 共有494条查询结果,搜索用时 15 毫秒
81.
We further study the projective synchronization of a new hyperchaotic system. Different from the most existing methods, intermittent control is applied to chaotic synchronization in the present paper. We formulate the intermittent control system that governs the dynamics of the projective synchronization error, then derive the sufficient conditions for the exponential stability of intermittent control system by using Lyapunov stability theory, and finally establish the periodically intermittent controller according to the stability criterion by which the projective synchronization is expected to be achieved. The analytical results are also demonstrated by several numerical simulations. 相似文献
82.
This paper further investigates the lag synchronization of coupled delayed systems with parameter mismatch. Different from the most existing results, we formulate the intermittent control system that governs the dynamics of the synchronization error. As a result of parameter mismatch, complete lag synchronization cannot be achieved. In this paper, a lag quasisynchronization scheme is proposed to ensure that coupled systems are in a state of lag synchronization with an error level. We estimate the error bound of lag synchronization by rigorously theoretical analysis. Numerical simulations are presented to verify the theoretical results. 相似文献
83.
84.
利用一维固-流结构矩形掺杂声子晶体中弹性波横向受限的条件,推导出弹性波在一维固-流结构矩形掺杂声子晶体中各个模式满足的关系式.研究弹性波各模式的缺陷模随模式量子数和杂质厚度的变化规律.利用缺陷模随模式量子数的变化规律可以实现多通道滤波,利用缺陷模随杂质厚度的变化规律可以实现调谐滤波. 相似文献
85.
以Ce3+为中心离子,N,N-二甲基甲酰胺(DMF)为有机配体,通过温度调节,合成系列形貌和电化学信号不同的铈配合物(Ce-COPs)。筛选出电化学信号最强的多面体状Ce-COP为信号探针。通过凝血酶(TB)与TB适体链之间的特异性识别作用,设计了一种简单通用的TB适体传感器。最优实验条件下,该传感器对TB的线性响应范围为1.0 fmol·L-1~1.0 nmol·L-1,检测限为0.94 fmol·L-1。此外,本方案方法与商品人凝血酶(TM) ELISA试剂盒检测结果相近。结果表明,我们构建的TB适体传感器具有良好的灵敏度、特异性、选择性和稳定性。 相似文献
86.
固-液结构圆柱声子晶体中弹性波的模式和带隙 总被引:3,自引:1,他引:2
利用一维固-液结构圆柱声子晶体中弹性波横向受限的条件,推导弹性波在一维固-液结构圆柱声子晶体中各个模式满足的关系式,研究各个模式弹性波的特征.并用色散函数计算各模式弹性波的带隙随模式量子数和圆柱半径的变化规律.得出一维固-液结构圆柱声子晶体的带隙由模式量子数和圆柱半径确定. 相似文献
87.
固-流结构声子晶体中弹性波能带的色散研究 总被引:6,自引:1,他引:5
推导出弹性波斜入射固-流结构声子晶体的转移矩阵和色散公式.利用色散公式研究了弹性波在固-流结构声子晶体中的能带特性.结果表明,介质厚度固定时,弹性波中会出现多级禁带,禁带的频率中心随入射角的增加而向高频方向移动,入射角增加到一定值后会分裂出新的禁带,分裂出的禁带频率宽度随级数的增加而增大.入射角固定时,禁带的频率宽度随介质厚度近似成反比变化,分裂出的禁带频率宽度随介质厚度的增加而减小. 相似文献
88.
ZENG Xiao-Xiong HAN Yi-Wen YANG Shu-Zheng 《理论物理通讯》2009,51(1):187-189
Based on the covariant anomaly cancellation method, which is believed to be more refined than the initial approach of Robinson and Wilczek, we discuss Hawking radiation from the plane symmetric black hole. The result shows that Hawking radiation from the non-spherical symmetric black holes also can be derived from the viewpoint of anomaly. 相似文献
89.
The paper is concerned with the state estimation problem for a class of neural networks with Markovian jumping parameters.
The neural networks have a finite number of modes and the modes may jump from one to another according to a Markov chain.
The main purpose is to estimate the neuron states, through available output measurements such that for all admissible time-delays,
the dynamics of the estimation error are globally stable in the mean square. A new type of Markovian jumping matrix P
i
is introduced in this paper. The discrete delay is assumed to be time-varying and belong to a given interval, which means
that the lower and upper bounds of interval time-varying delays are available. Based on the new Lyapunov–Krasovskii functional,
delay-interval dependent stability criteria are obtained in terms of linear matrix inequalities (LMIs). Finally, numerical
examples are provided to demonstrate the less conservatism and effectiveness of the proposed LMI conditions. 相似文献
90.
QIN Mao-Chang MEI Feng-Xiang FAN Gui-Hong 《理论物理通讯》2006,46(1):21-22
This paper introduces an effective method for seeking local conservation laws of general partial differential equations (PDEs). The well-known variational principle does not involve in this method. Alternatively, the conservation laws can be derived from symmetries, which include t/he symmetries of t/he associated linearized equation of t/he PDEs, and the adjoint symmetries of the adjoint eqUation of the PDEs. 相似文献