The periodic nature of the positive solutions of a nonlinear fuzzy max-difference equation

We investigate the periodic nature of the positive solutions of the fuzzy difference equation , where k, m are positive integers, A₀, A₁, are positive fuzzy numbers and the initial values x_i, i = −d, −d + 1, … , −1, d = max{k, m}, are positive fuzzy numbers. In addition, we give conditions so that the solutions of this equation are unbounded.     

Limitations of nonlinear discrete periodic control for disturbance attenuation and robust stabilization

This paper presents a performance analysis of nonlinear periodically time-varying discrete controllers acting upon a linear time-invariant discrete plant. Time-invariant controllers are distinguished from strictly periodically time-varying controllers. For a given nonlinear periodic controller, a time-invariant controller is constructed. Necessary and sufficient conditions are given under which the time-invariant controller gives strictly better control performance than the time-invariant controller from which it was obtained, for the attenuation of l_p exogenous disturbances and the robust stabilization of l_p unstructured perturbations, for all p[1,∞].     

超混沌系统自周期轨道链接式控制

基于混沌同步和周期轨道理论提出一种超混沌系统自周期轨道链接式控制法。从超混沌系统状态变量的时间序列中提取周期轨道并用于对系统的实时控制,可使混沌系统稳定运行于某一周期轨道。将提周期轨道经链接组合后用于系统控制,可得到大量的大周期轨道。对4阶蔡氏电路进行数字仿真实验,获得了满意的结果。     

具有重置时间切换服务系统的动态稳定性

由一个Server和多个Buffers组成的考虑重置时间的切换服务系统可建模为连续 流切换系统.当采用优先权调度策略时,证明了切换服务系统的连续状态轨迹能一致收敛于 惟一的周期轨道,指出周期轨道与初始状态无关,并给出收敛速度估计.     

周期环境下的最优的脉冲控制策略

研究了周期环境影响下具有脉冲控制的捕食与被捕食模型的全局动态行为,通过Floqnet理论和微分方程比较定理,得到了捕食系统害虫根除周期解的全局稳定性的临界值,进一步数值模拟分析了系统参数如何影响害虫综合控制,得到了最优的脉冲控制策略．     

Periodic and solitary wave solutions of the attractive and repulsive nonlinear Schrödinger equation

By means of symbolic computation, the first integral method is presented to obtain novel exact solutions of the nonlinear evolution equation. The obtained results include periodic and solitary wave solutions. The power of this manageable method is confirmed and the availability of symbolic computation is demonstrated.     

基于仿真方法的任务集可调度性判定工具

针对含有纯周期任务的任务集可调度性判定问题,提出一种基于仿真方法的任务集可调度性判定工具。通过设定时钟变量,模拟任务调度过程中的系统时钟,在时钟变量值增长的过程中,根据任务优先级从高到低的顺序,分析各个任务的截止时间限,判定任务集的可调度性。实例分析证明了该工具的可调度性判定结果正确。     

特殊周期序列K-错线性复杂度的快速算法

给出一个特殊周期序列GF（3）上周期为3pm的序列的K-错线性复杂度的快速算法,并讨论了它的正确性.其中p为素数,而且3是模p2的本原根.     

Prüfer method for periodic and semi-periodic sturm-liouville eigenvalue problems ∗

In reference [19], the authors developed a shooting algorithm for Sturm-Liouville eigenvalue problems associated with periodic and semi-periodic boundary conditions. The technique is based on the application of the Floquet theory, and it has proven to be efficient for computing eigenvalues. However, the performance of this technique depends upon the choice of the starting eigenvalues. In the present paper, we continue our study and employ the Prüfer method. An attractive property of this method is that eigenvalues can usually be accurately computed even when no information on the eigenvalue distribution is provided. Sufficient conditions for convergence, error bounds and a procedure to improve the stability are discussed. Some numerical examples are given to illustrate the effectiveness of the proposed method.     

四阶泛函微分方程周期解的存在性和全局吸引性

研究四阶泛函微分方程x^（4）（t）＋a1x^′′′（t）＋a2x^′′（t）＋a3x^′（t）＋a4x（t）＋g（t,x（t—τ））=p（t）的周期解问题．首先将该方程转变为四维的拟线性微分方程（组）,得到该方程存在唯一周期解的充分条件;然后通过选取适当的李雅普诺夫函数,推导方程任一解的全局吸引性,并进一步得到方程周期解的全局吸引性．最后,通过实例证实了本文结果的正确性．