Positive-Controllability,Positive-Near-Controllability,and Canonical Forms of Driftless Discrete-Time Bilinear Systems

Controllable canonical forms play important roles in the analysis and design of control systems. In this paper, a fundamental class of discrete-time bilinear systems are considered. Such systems are of interest since, on one hand, they have the most complete controllability theory. On the other hand, they can be nearly-controllable even if controllability fails. Firstly, controllability of the systems with positive control inputs is studied and necessary and sufficient algebraic criteria for positive-controllability and positive-near-controllability are derived. Then, controllable canonical forms and nearly-controllable canonical forms of the systems are presented, respectively, where the corresponding transformation matrices are also explicitly constructed. Examples are given to demonstrate the effectiveness of the derived controllability criteria and controllable canonical forms.

     

Leader selection for strong structural controllability of single-integrator multi-agent systems

This paper addresses the leader selection problem for strong structural controllability (SSC) of multi-agent systems (MASs). For a path-bud graph, it is proved that only one leader is required to guarantee the SSC of MASs. For a special type of topologies, based on the partition of the topology into disjoint pathes and path-buds, it is proved that the MASs is strongly structurally controllable if the root nodes of the pathes are selected as leaders. For general topologies, an algorithm is provided to determine the agents that can behave as leaders. For some special topologies, the minimum number of leaders guaranteeing the robust strong structural controllability (RSSC) of MASs is also obtained. Two examples are given to verify the effectiveness of the results.     

Application of Sturm Theorem in the Global Controllability of a Class of High Dimensional Polynomial Systems

In this paper, the global controllability for a class of high dimensional polynomial systems has been investigated and a constructive algebraic criterion algorithm for their global controllability has been obtained. By the criterion algorithm, the global controllability can be determined in finite steps of arithmetic operations. The algorithm is imposed on the coefficients of the polynomials only and the analysis technique is based on Sturm Theorem in real algebraic geometry and its modern progress.Finally, the authors will give some examples to show the application of our results.     

Research on controllability for a class of fractional-orderlinear control systems

1.INTRODUCTION Therealobjectsaregenerallyfractional[1],however,thecontrolsystemsusedsofarareallconsideredas integer ordersystems.Thereasonisthecomplexity andtheabsenceofadequatemathematicaltoolsfor fractional ordersystems.Fractionalcalculusisanatu ralextensionoftheclassicalmathematics.Thefrac tionalcalculustheorywasdevelopedbyalotofmath ematicians[2,3]andtheapplicationdomainsoffrac tionalcalculushaveincreasedsignificantly.Lasttwo decadestheknowledgewasappliedincontroltheory,whichconcerned…     

Reachability/controllability of high order mix-valued logical networks

This paper addresses the reachability/controllability of high order mix-valued logical control networks by using the semi-tensor product method, and presents some necessary and sufficient conditions for the reachability/controllability. The high order mix-valued logical network is converted into an algebraic form first, based on which the reachability/controllability of the system is then investigated, and several necessary and sufficient conditions are established. The study of several illustrative examples shows that our new method is very effective in dealing with the reachability/controllability of high order mix-valued logical control networks.     

Controllability and observability of networked control systems with time-varying delays

The controllability and observability of networked control systems are studied. Aiming at the networked control system with time-varying delay, the sufficient and necessary conditions for complete controllability and complete observability of the system are presented, respectively. Because of Markov characteristic of the network-induced delay, in terms of stochastic theory, a sufficient and necessary condition for completely mean value controllability of networked control systems is obtained. Further, the conditions that the controllability and observability of networked control systems are equivalent to the initial time-invariant system are given. Controllability and observability realization indexes are also discussed, respectively. The numerical example demonstrates the effectiveness of the proposed theory.     

On controllability for stochastic control systems when the coefficient is time-variant

<正> This paper investigates the controllability problem of time-variant linear stochastic controlsystems.A sufficient and necessary condition is established for stochastic exact controllability,whichprovides a useful algebraic criterion for stochastic control systems.Furthermore,when the stochasticsystems degenerate to deterministic systems,the algebraic criterion becomes the counterpart for thecomplete controllability of deterministic control systems.     

一类动力系统的时滞脉冲控制

针对脉冲控制中,时滞在脉冲采样时刻客观存在这样一种现象,研究了一类动力系统的时滞脉冲控制问题。给出了在时滞脉冲控制下,这类动力系统的原点是全局渐近稳定的一个充分条件,该条件反映了系统参数,脉冲区间和延迟时间之间的相关关系。利用所得的结论,也实现了这类系统的时滞脉冲同步。最后,以典型的分段线性系统Chua电路和非线性的混沌Chen系统为例,分别通过数值仿真实验验证了理论结论的有效性。     

Optimal Output Feedback Control and Stabilization for NCSs with Packet Dropout and Delay: TCP Case

This paper considers the output feedback control and stabilization problems for network control systems (NCSs) with packet dropout and input delay, and the TCP (transmission control protocol) case is mainly investigated. Specifically, whether the control signal is lost can be acknowledged by the receiver in the NCSs. The main contributions are: 1) For the finite horizon case, the “optimal” output feedback control is derived by using the dynamic programming approach, and it is noted that the separation principle holds for the considered situation; 2) For the infinite horizon case, for the first time, the necessary and sufficient stabilization conditions are derived for NCSs with packet dropout and delay.     

Stability of impulsive linear hybrid systems with time delay

<正> This paper investigates the stability of impulsive linear hybrid systems with time delay.And a number of delay-independent/delay-dependent stability criteria are obtained by using Lyapunovfunctions or Lyapunov functionals.Two examples are also presented to illustrate the effectiveness ofthe obtained results or to compare with the existing results.     

基于LMIs方法-不确定性随机分布型时滞Markov跳变系统的鲁棒镇定

研究了一类具有不确定性Markov跳变参数的线性分布型时滞系统.考虑了具不确定性、Markov跳变参数、及分布型时滞系统的鲁棒均方稳定性问题.设计了系统的鲁棒状态反馈镇定控制器.采用了Grownwall Bellman不等式,基于线性矩阵不等式(LMIs)方法,给出了鲁棒稳定性的LMI时滞依赖的代数判据,从而降低了判据的保守性.同时得到了相应的离散时滞情形下的结果.     

一种基于样本的综合评价方法及其在FSA中的应用研究

给出了一种基于多个样本单元或给定标准的多目标、多准则综合评价方法 ,并讨论了它的相关性质 .同时 ,还给出了一种依据样本前沿面移动划分可行集的算法 ( MSF) .根据划分的各区域特征 ,可以对决策单元的性状进行比较或排序 .在此基础上 ,给出了 n维空间中最大可接受风险曲面的概念 ,推广了传统的 F-N曲线分析方法 .并将 MSF应用于多风险区域分划以及同类单元综合风险评估 ( FSA)等问题中 .     

The Stability of Nonlinear Time-Delay Discrete Systems

1IntroductionSincethe1950s,thediscretesystemsmodel(thedifferenceequatioll)hasbeenaveryimportantalldusefulmathematicalmodelforengineersofalldisciplilles,physicists,biologists,economists,andsocialscientistsgiventheapplicationofdigitalcomputerstoengilleeringandsicence.Thereforetheinvestigationofthediscretesystemsmodelhasbecomeillcrea.singlyimportant.Fromthe1950stothepresent,mostworkhasbeendoneonsample-datasystenasbymeansoftheZ-transform.Inrecentdecades,thestudyofthediscretesystemsmodelhasdevelop…     

具有变时滞的线性系统的时滞相关稳定性

具有时滞的控制系统是工程实践中经常遇到的一类重要的非线性控制系统。根据微分方程理论和矩阵指数特性，提出了具有不确定性的时滞控制系统与时滞相关和与时滞无关稳定的充分性判据，并给出系统衰减速率的估计方法。该方法仅需假定时滞有界，因而其结论适用于变时滞的系统。同时还给出了应用实例，并与相关成果进行了比较，计算结果表明了该方法的有效性。     

Improved delay-dependent stability criteria for systems with interval delay

This paper deals with the problem of stability for systems with delay varying in an interval.A new Lyapunov functional,which makes use of the information of both the lower and upper bounds of the interval time-varying delay,is proposed to derive some new stability criteria.Furthermore,the relationship of the time-varying delay and its lower bound and upper bound is taken into account.As a result,some less conservative delay-dependent stability criteria are obtained without ignoring any useful information in the derivative of Lyapunov functional,which are established in the forms of linear matrix inequalities.Numerical examples are provided to show that the obtained results are better than existing ones.     

Optimal Output Tracking Control and Stabilization of Networked Control Systems with Packet Losses

This paper studies the optimal output tracking control and stabilization for networked control systems with packet losses via output feedback control. Both finite-horizon and infinite-horizon cases are considered. For the finite-horizon case, the authors introduce an augmented system according to the state variable and the reference trajectory for the first time. Based on a set of difference Riccati equations, an optimal output feedback tracking controller is proposed by applying the stochastic maximum principle. And an optimal estimator is presented. For the infinite-horizon case, a necessary and sufficient condition for the stabilization of the system is provided. And an optimal output feedback stabilizing tracking controller is obtained by establishing a set of algebraic Riccati equations. Finally,numerical examples are given to verify the proposed results.     

Event-Triggered Adaptive Fuzzy Finite Time Control of Fractional-Order Non-Strict Feedback Nonlinear Systems

In this article, the problem of event-triggered adaptive fuzzy finite time control of non-strict feedback fractional order nonlinear systems is investigated. By using the property of fuzzy basis function, the obstacle caused by algebraic loop problems is successfully circumvented. Moreover, a new adaptive event-triggered scheme is designed under the unified framework of backstepping control method, which can largely reduce the amount of communications. The stability of the closed-loop system is ensured through fractional Lyapunov stability analysis. Finally, the effectiveness of the proposed scheme is verified by simulation examples.

     

时延网络控制系统的区域极点配置设计

针对存在时变有界时延的网络控制系统,在一定假设条件下,基于分离原理讨论了状态观测器和状态反馈控制器的设计方法。状态观测器通过在开环预测和闭环预测间切换以补偿时延的影响,同时考虑时延的时变性以及回路中长时延的存在,闭环预测也是在多个模型间切换,从而将状态观测器建模成具有多个子系统的离散切换系统。在此基础上,利用预测状态作为控制器的输入,设计了具有圆盘区域极点约束的状态反馈控制器。最后以线性矩阵不等式可行解的方式分别给出了控制器和观测器的构造方法,仿真结果说明了所提出方法的有效性。     

Study on Robust Uniform Asymptotical Stability for Uncertain Linear Impulsive Delay Systems

In the area of control theory the time-delay systems have been investigated. It's well known that delays often result in instability, therefore, stability analysis of time-delay systems is an important subject in control theory. As a result, many criteria for testing the stability of linear time-delay systems have been proposed. Significant progress has been made in the theory of impulsive systems and impulsive delay systems in recent years. However, the corresponding theory