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.     

NECESSARY AND SUFFICIENT CONDITION FOR GLOBAL CONTROLLABILITY OF A CLASS OF AFFINE NONLINEAR SYSTEMS

In this paper, we investigate the global controllability of a class of n-dimensional affine nonlinear systems with n- 1 controls and constant control matrix. A necessary and sufficient condition for its global controllability has been obtained by using the methods recently developed. Furthermore, we generalize the above result to a class of affine nonlinear systems with a block-triangular-like structure. Finally, we will give three examples to show the applications of our results.     

二维广义系统Roesser模型局部能达和局部能控性

研究了二维广义系统Roesser模型的性质,推导出了该系统的状态响应公式.给出了其在矩形区域上局部能达和局部能控的充分必要条件.同时,利用二维Z变换理论,给出了二维广义系统Roesser模型局部能达和局部能控的等价定义,并得出该模型相应的局部能达和局部能控的新的充分必要条件.     

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…     

一类线性切换系统的能控性和能观测性的充要条件

循环不变子空间是常用于控制科学和信号处理理论的重要数学工具之一。用循环不变子空间的性质研究了切换系统的能控性和能观测性。先给出了切换系统能控性、能达性和能观测性的概念,并讨论了循环不变子空间的性质。然后用循环不变子空间的性质研究了周期线性切换系统的能控制性、能达性及能观测性,得到线性周期切换系统完全能控和完全能观测的充分必要条件。最后给出一般线性切换系统完全能控和完全能观测的充分条件和必要条件。     

Impulse Controllability and Impulse Observability of Stochastic Singular Systems

This paper discusses the impulse controllability and impulse observability of stochastic singular systems. Firstly, the condition for the existence and uniqueness of the impulse solution to stochastic singular systems is given by Laplace transform. Secondly, the necessary and sufficient conditions for the impulse controllability and impulse observability of systems considered are derived in terms of matrix theory. Finally, an example is given to illustrate the effectiveness of the obtained theoretical results.     

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.

     

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.     

Generating semi-algebraic invariants for non-autonomous polynomial hybrid systems

Hybrid systems are dynamical systems with interacting discrete computation and continuous physical processes, which have become more common, more indispensable, and more complicated in our modern life. Particularly, many of them are safety-critical, and therefore are required to meet a critical safety standard. Invariant generation plays a central role in the verification and synthesis of hybrid systems. In the previous work, the fourth author and his coauthors gave a necessary and sufficient condition for a semi-algebraic set being an invariant of a polynomial autonomous dynamical system, which gave a confirmative answer to the open problem. In addition, based on which a complete algorithm for generating all semi-algebraic invariants of a given polynomial autonomous hybrid system with the given shape was proposed. This paper considers how to extend their work to non-autonomous dynamical and hybrid systems. Non-autonomous dynamical and hybrid systems are with inputs, which are very common in practice; in contrast, autonomous ones are without inputs. Furthermore, the authors present a sound and complete algorithm to verify semi-algebraic invariants for non-autonomous polynomial hybrid systems. Based on which, the authors propose a sound and complete algorithm to generate all invariants with a pre-defined template.     

Impulse observability and impulse controllability of regular degenerate evolution systems

Impulse observability and impulse controllability of regular degenerate evolution systems are discussed by using functional analysis and operator theory in Banach space. Necessary and sufficient conditions for the impulse observability and impulse controllability of the system are obtained. This research is theoretically important for studying the design of the degenerate evolution system.     

长期资产投资组合策略的演化稳定性

利用随机动力系统理论研究了金融市场长期资产投资组合策略财富占有比例的动态演化模型.其中资产价格是内生的, 每期末支付的股息或红利收益只用于消费,在财富不断再投资的过程中, 投资组合的表现由财富的市场占有比例决定.将投资策略和红利收益纳入同一自然状态中考虑其相互影响,分析了固定投资组合策略演化稳定性的充分必要条件,在自然状态服从独立同分布和Markov过程时,给出了唯一的演化稳定投资策略, 得到了一些更加直观具体的结果.进一步,利用中国股市数据,通过计算机进行数值模拟验证了演化稳定投资策略的长期效应.研究结果对证券市场投资策略选择 及探讨市场有效性提供了重要的理论依据.     

On Robust Stability of a Class of Uncertain Nonlinear Systems with Time—Varying Delay

The problem of robust stability of a class of uncertain nonlinear dynamical systems with time-delay is considered. Based on the assumption that the nominal system is stable, some sufficient conditions on robust stability of uncertain nonlinear dynamical systems with time-delay are derived. Some analytical methods and a type of Lyapunov functional are used to investigate such sufficient conditions. The results obtained in this paper are applicable to perturbed time-delay systems with unbounded time-varying delay. Some previous results are improved and a numerical example is given to demonstrate the validity of our results.     

线性时变周期系统的能控性与能稳定性问题

线性时变周期系统是一类普遍存在的重要而又研究较少的系统。介绍了线性时变周期系统的几种应用实例,给出了两种判定时变周期系统能控性与能观性的必要条件,该判别条件的优点是不必计算系统的状态转移矩阵,使判别时变周期系统能控性与能观性简单、高效、易于实现。讨论了时变周期系统在状态反馈下的能稳定性问题,得到了类似于线性定常系统能控性与能稳定性关系的时变周期系统相应结论。说明了结论是线性定常系统相应结论的自然拓展。给出了数值算例的MATLAB仿真求解过程。仿真结果验证了结论的有效性。     

Controllability of Singular Distributed Parameter Systems in the Sense of Mild Solution

Necessary and sufficient conditions for the exact controllability and approximate controllability of a singular distributed parameter system are obtained. These general results are used to examine the exact controllability and approximate controllability of the Dzektser equation in the theory of seepage.     

EIGENSTRUCTURE ASSIGNMENT VIA DYNAMIC OUTPUT FEEDBACK

ThisresearchissupportedbytheNationalNaturalScienceFOundationandthePostdoctoralScienceFOundationofChina.feedback,controllability,observability.1.IntroductionEigenstructureassignment,asoneofthemostfundamentalproblemsinmoderncontroltheroy,wasstudiedextensivelyinthepast.Theassignabilityconditionsviastatefeedbackandpracticalalgorithmshavebeengiven[1--41.Inrecentyearsgtheproblemintheoutputfeedbackcasehasbeendiscussed.[51studiedthisproblembyusingtheconceptof(A,B)characteristicsubspace.[6--8]putt…     

Finite-time stability and stabilization of Markovian switching stochastic systems with impulsive effects

Many practical systems in physics,biology,engineering and information science exhibit impulsive dynamical behaviors due to abrupt changes at certain instants during the dynamical processes.The problems of finite-time stability analysis are investigated for a class of Markovian switching stochastic systems,in which exist impulses at the switching instants.Multiple Lyapunov techniques are used to derive sufficient conditions for finite-time stochastic stability of the overall system.Furthermore,a state feedback controller,which stabilizes the closed loop systems in the finite-time sense,is then addressed.Moreover,the controller appears not only in the shift part but also in the diffusion part of the underlying stochastic subsystem.The results are reduced to feasibility problems involving linear matrix inequalities (LMIs).A numerical example is presented to illustrate the proposed methodology.     

CONTROLLABILITY OF EVOLUTION INCLUSIONS WITH NONLOCAL CONDITIONS

In this paper we examine controllability problems of evolution inclusions with nonlocal conditions. Using Kakutani‘s fixed point theorem and Schauder‘s fixed point the-orem, we establish sufficient conditions for the controllability under convex and nonconvex orientor fields respectively.     

Recent progress on controllability/observability for systems governed by partial differential equations

<正> The main purpose of this paper is to overview some recent methods and results on controllability/observability problems for systems governed by partial differential equations.First,the authorsreview the theory for linear partial differential equations,including the iteration method for the nullcontrollability of the time-invariant heat equation and the Rellich-type multiplier method for the exactcontrollability of the time-invariant wave equation,and especially a unified controllability/observabilitytheory for parabolic and hyperbolic equations based on a global Carleman estimate.Then,the authorspresent sharp global controllability results for both semi-linear parabolic and hyperbolic equations,based on linearization approach,sharp observability estimates for the corresponding linearized systemsand the fixed point argument.Finally,the authors survey the local null controllability resultfor a class of quasilinear parabolic equations based on the global Carleman estimate,and the localexact controllability result for general hyperbolic equations based on a new unbounded perturbationtechnique.     

Perturbation and robust controllability of singular distributed parameter control systems in Hilbert space

Perturbation and robust controllability of the singular distributed parameter control system are discussed via functional analysis and the theory of GE-semigroup in Hilbert space.The perturbation principle of GE-semigroup and the sufficient condition concerning the robust controllability of the singular distributed parameter control system are obtained,in which the controllability for singular distributed parameter control system is not destroyed,if we perturb the equation by small bounded linear operator.