各向异性的群集行为分析

探究欧氏空间中一类具有吸引/排斥函数的各向异性群集系统的集结属性,将个体间的耦合矩阵进行了一定的推广.该模型的耦合矩阵更具普遍意义.结果表明:在耦合权值满足一定平衡条件的情况下,群集成员将在有限时间内聚集并形成一个以群集的加权中心为球心的紧凑的有界群体.仿真实例进一步表明了群集个体最终进入并驻留在群集加权中心的有界区域内.     

0-1背包问题的蜂群优化算法

在项目决策与规划、资源分配、货物装载、预算控制等工作中,提出了0-1背包问题.0-1背包问题是组合优化中的典型NP难题,根据群集智能原理,给出一种基于蜂群寻优思想的新算法—蜂群算法,并针对0-1背包问题进行求解.经实验仿真并与蚁群算法计算结果作对比,验证了算法在0-1背包问题求解上的有效性和更快的收敛速度.     

Lyapunov-Razumikhin定理应用于多自主体系统的编队问题

在群集中编队是很普遍的.研究了没有"leader"的群集编队问题.考虑输入端带有扰动和时滞.所考察的多智主体系统具有固定和切换拓扑两种情况.应用Lyapunov-Razumikhin定理到输入有时滞影响的编队问题中.解决了输入端有时滞和扰动以及主体是单"integrators"情形的编队问题.     

图拉普拉斯矩阵引出的对角稳定矩阵的讨论（英文）

如果有向图G含有生成树,并且M由G的闭强连通分支外节点构成拓扑所对应的L的一个子矩阵,其中L是图G的拉普拉斯矩阵,那么矩阵M是对角稳定的.在多智能体系统协同一致算法的设计中,常常需要寻找正定对角矩阵E,使得-EM-M~TE0.结合前期研究成果,文章旨在给出一种新的分布式算法来构造矩阵E,该算法只需要关于多智能体系统网络拓扑图G的局部结构信息.     

带有不稳定模态的非线性切换系统镇定方法综述

非线性切换系统的分析和综合是近年来控制领域的研究热点,具有重要的理论价值和实际意义.文章总结了带有不稳定模态非线性切换系统镇定的最新研究成果,分别讨论了带有部分不稳定模态和带有全部不稳定模态两种情况,并介绍了理论成果的若干实际应用方向,如容错控制,多智能体协同控制,网络化控制等,最后对该研究方向进行了展望.     

事件触发下多智能体系统规定时间二分一致性

针对线性合作竞争多智能体系统(MAS),考虑到可能受到的外部干扰,研究了系统基于事件触发机制的规定时间二分一致性控制问题.首先,设计干扰观测器估计系统受到的外部干扰,且针对每个智能体给出了事件触发条件,以减少智能体间的通信频率,节省有限的通信网络资源,同时证明避免了Zeno现象,其次,为了明确地预先分配稳定时间,结合干扰观测器的估计值,设计了一种合作和竞争并存拓扑结构的规定时间事件触发控制协议,以保证所有智能体在受到外部干扰的情况下仍然达到二分一致.最后,利用仿真实例验证了所提出方法的可行性和有效性.     

自回归条件异方差模型在我国沪市的应用研究

应用自回归条件异方差(ARCH)模型对上海股市2000年—2004年4月上证指数收益率进行建模分析;实证结果反映上证指数收益率具有明显的群集聚集性、波动性、尖峰厚尾的特征,并且ARCH模型的预测能力较强.     

聚集数据多元线性模型参数的多元聚集综合岭估计的相对效率

对于聚集数据的多元线性模型,提出了参数的多元聚集综合岭估计的概念,给出了多元聚集综合岭估计相对于最小二乘估计及最佳线性无偏估计的两种相对效率,并得到了这两种相对效率的上界.应用Monte Carlo模拟,验证了有关结论是合理的.     

多元智能理论在数学教学中的运用

1　多元智能理论——时代的需要“多元智能”理论是在 1983年 ,由美国哈佛大学加德纳教授提出来的 .该理论对传统的智力定义和测量手段提出了挑战 ,拓展了对人的智能的研究领域 ,特别对教育、教学方法和教育评价产生了很大的冲击 .“多元智能”认为每个人除了语言智能和逻辑——数学智能外 ,至少还有其他 7种智能——“空间智能”、“音乐智能”、“人际关系智能”、“自我认识智能”、“身体运动智能”、“自然观察者智能”、“存在智能”.它关注的问题是 :“你的智能类型是什么 ?”学生的智能无高低之分 ,只有智能倾向的不同和强弱的差别 …     

聚集数据线性模型广义聚集双参数估计的相对效率

对于聚集数据的线性模型,提出了广义聚集双参数估计的概念,给出了广义聚集双参数估计的两种相对效率,并得到了这两种相对效率的上界.     

Analytical and numerical methods for the stability analysis of linear fractional delay differential equations

In this paper, several analytical and numerical approaches are presented for the stability analysis of linear fractional-order delay differential equations. The main focus of interest is asymptotic stability, but bounded-input bounded-output (BIBO) stability is also discussed. The applicability of the Laplace transform method for stability analysis is first investigated, jointly with the corresponding characteristic equation, which is broadly used in BIBO stability analysis. Moreover, it is shown that a different characteristic equation, involving the one-parameter Mittag-Leffler function, may be obtained using the well-known method of steps, which provides a necessary condition for asymptotic stability. Stability criteria based on the Argument Principle are also obtained. The stability regions obtained using the two methods are evaluated numerically and comparison results are presented. Several key problems are highlighted.     

Stability conditions for a pipeline polling scheme in satellite communications

This paper considers the unknown stability conditions of a pipeline polling scheme proposed for satellite communications. This scheme is modelled as a cyclic-service system with limited service and reservation. The walk times and the maximum number of services to be performed during each polling are dependent on the queue lengths of the stations. The main result is the derivation of the necessary and sufficient stability conditions of the system. Our approach is to map the multi-dimensional stability problem into many 1-dimensional stability problems through the concept of the least stable queue. The least stable queue is one that will become unstablefirst when the system load increases in some parameter region. The stability of the least stable queue thus implies stability of the system. The stability region for the whole system is then the union of the queue stability regions of all the least stable queues that are obtained through dominant systems and Loynes' theorem. We also propose a computable sufficient condition that is tighter than the existing result and present some numerical results.     

Delay-Dependent Criteria for Robust Stabilization of Markovian Switching Networks with Time-Varying Delay

Abstract

A problem of feedback stabilization of hybrid systems with time-varying delay and Markovian switching is considered. Delay-dependent sufficient conditions for stability based on linear matrix inequalities (LMI's) for stochastic asymptotic stability is obtained. The stability result depended on the mode of the system and of delay-dependent. The robustness results of such stability concept against all admissible uncertainties are also investigated. This new delay-dependent stability criteria is less conservative than the existing delay-independent stability conditions. An example is given to demonstrate the obtained results.     

$n$-维中立型多时滞微分方程的稳定性分析

This paper is mainly concerned with stability analysis of neutral differential equations with multiple delays. Some criteria on instability, stability, asymptotic stability and exponential stability are obtained. The criterion on asymptotic stability is necessary and sufficient. Two examples are provided to illustrate the applications of our results. Some previous results are extended.     

The stability and stabilization of the motion of non-conservative mechanical systems

Two stability problems are solved. In the first, the stability of mechanical systems, on which dissipative, gyroscopic, potential and positional non-conservative forces (systems of general form) act, is investigated. The stability is considered in the case when the potential energy has a maximum at equilibrium. The condition for asymptotic stability is obtained by constructing Lyapunov's function. In the second problem, the possibility of stabilizing a gyroscopic system with two degrees of freedom up to asymptotic stability using non-linear dissipative and positional non-conservative forces is investigated. Stability of the gyroscopic system is achieved by gyroscopic stabilization. The stability conditions are obtained in terms of the system parameters. Cases when the gyroscopic stabilization is disrupted by these non-linear forces are indicated.     

The effect of density-dependent dispersal on the stability of populations

The nonlinear stability of two populations diffusing in a common bounded domain with nonlinear density-dependent dispersal of a general type is studied, under Robin boundary conditions. The stability and instability of the positive equilibrium are studied by the linear eigenvalues method. The nonlinear stability is studied with the Lyapunov direct method. In a particular case, global stability has been obtained.     

假设检验的相对稳定性

郑祖康^[1]提出了数理统计学中一个有意义的新问题－假设检验的稳定性。但是,由于稳定性定义的条件太强,从而通常检验统计量的稳定性并不好。本文根据假设检验的实际意义,定义了假设检验的相对稳定性,讨论了一类常用检验统计量的相对稳定性的一些性质,作为特例,得到似然比检验的相对稳定性的性质。     

Global asymptotic stability of stochastic fuzzy cellular neural networks with multiple discrete and distributed time-varying delays

In this paper, the Takagi–Sugeno (T–S) fuzzy model representation is extended to the stability analysis for stochastic cellular neural networks with multiple discrete and distributed time varying delays. A novel linear matrix inequality (LMI) based stability criterion is derived to guarantee the asymptotic stability of stochastic cellular neural networks with multiple discrete and distributed time varying delays which are represented by T–S fuzzy models. The derived delay-dependent stability conditions are based on free-weighting matrices method, Lyapunov stability theory and LMI technique. In fact, these techniques lead to generalized and less conservative stability condition that guarantee the wide stability region. The delay-dependent stability condition is formulated, in which the restriction of the derivative of the time-varying delay is removed. Our results can be specialized to several cases including those studied extensively in the literature. Finally, numerical examples are given to demonstrate the effectiveness and conservativeness of our results.     

On the mean square stability of linear difference equations

The mean square asymptotic stability of linear stochastic difference equations is studied. The Liapunov method of stability analysis is extended to stochastic difference equations, and several criteria for the mean square stability of the equilibrium state are established. Two examples of the application of the stability theorems are also considered.