图像小波域局部统计模型的拟合优度检验

提出了一种图像小波域局部统计模型的拟合优度检验方法, 构造了一个检验的统计量, 其分布为$\chi^2$-分布. 模拟结果表明, 不同分块下的拟合优度检验结果不同, 即从理论上给出了基于小波域局部统计模型的最优分块方法.     

Analysing chaos in fractional-order systems with the harmonic balance method

In this paper, the fractional-order Genesio--Tesi system showing chaotic behaviours is introduced, and the corresponding one in an integer-order form is studied intensively. Based on the harmonic balance principle, which is widely used in the frequency analysis of nonlinear control systems, a theoretical approach is used to investigate the conditions of system parameters under which this fractional-order system can give rise to a chaotic attractor. Finally, the numerical simulation is used to verify the validity of the theoretical results.     

Synchronization in a unified fractional-order chaotic system

In this paper, the synchronization in a unified fractional-order chaotic system is investigated by two methods. One is the frequency-domain method that is analysed by using the Laplace transform theory. The other is the time-domain method that is analysed by using the Lyapunov stability theory. Finally, the numerical simulations are used to illustrate the effectiveness of the proposed synchronization methods.     

Chaotifying a stable linear controllable system by single input state feedback

In this paper, an approach for chaotifying a stable controllable linear system via single input state-feedback is presented. The overflow function of the system states is designed as the feedback controller, which can make the fixed point of the closed-loop system to be a snap-back repeller, thereby yields chaotic dynamics. Based on the Marotto theorem, it proves theoretically that the closed-loop system is chaotic in the sense of Li and Yorke. Finally, the simulation results are used to illustrate the effectiveness of the proposed method.     

混沌模拟退火最短路由算法的事后处理技术

基于混沌模拟退火神经网络的最短路径路由算法，虽然能有效地克服Hopfield神经网络易陷入局部最小值的缺点，但对节点数较多的网络，仍有缺陷。引进了一种事后修正机制，即在结果修正时，结合具体问题，充分考虑解的合法性，根据神经网络的输出矩阵，依次找到该行的最大值，确定与该节点相连的下一个最短路径节点。仿真结果显示既使网络节点数较多，这一算法仍运行良好且能以较大的概率找到全局最优解。