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In this article, a robust quadratic-boundedness-based model predictive control (MPC) scheme, for a discrete-time nonlinear Markov jump system (MJS), is extended to the case with persistent bounded disturbance and nonhomogeneous transition probability. By applying the S-procedure, the constraint conditions, the persistent bounded disturbance and the sufficient stability conditions are all derived in term of a few linear matrix inequalities (LMIs), thus the original min-max optimization problem is transformed into a convex optimization problem in LMI paradigm. At each sampling time, the control moves satisfying the control constraint are obtained online and implemented in the nonlinear MJS. Quadratically boundedness and min-max MPC are combined to achieve the closed-loop stochastic stability of the controller with respect to the persistent bounded disturbance. A numerical example is presented to demonstrate the effectiveness of the proposed results.

This paper aims to investigate an efficient numerical scheme for the optimal control of fractional-order dynamic systems. By using the Grünwald–Letnikov approximation for the fractional derivatives and introducing a new transformation in the calculus of variations, the fractional optimal control problem under consideration is converted into a linear programming problem. Then, the internal model principle is employed in order to extend the new scheme for the fractional dynamic systems affected by the external persistent disturbances. Numerical examples and comparative results verify the validity and applicability of the new technique. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop an efficient iterative approach for solving a class of time-delay optimal control problems with time-varying delay and external persistent disturbances. By using the internal model principle, the original time-delay model with disturbance is first converted into an augmented system without any disturbance. Then, we select a quadratic performance index for the augmented system to form an undisturbed time-delay optimal control problem. The necessary optimality conditions are then derived in terms of a two-point boundary value problem involving advance and delay arguments. Finally, a fast iterative algorithm is designed for the latter advance-delay boundary value problem. The convergence of the new iterative technique is also investigated. Numerical simulations verify that the proposed approach is efficient and provides satisfactory results. [ABSTRACT FROM AUTHOR]

This article deals with the leader-following mean-square consensus problem of discrete-time general linear multi-agent systems with Markovian switching topologies and persistent disturbances. Assume that the communication topology is not connected at any time but the union topology is connected. First, the estimators are designed to calculate the states of agents when external disturbance not exists. Based on the error information between the truth-values and estimatedvalues of states, the compensators are proposed to subject to the effect of persistent disturbances. And then, a new mean-square consensus control protocol is proposed for each agent. Second, by using the property of permutation matrix, the original closed-loop system is transferred into an equivalent system. Third, sufficient conditions for meansquare consensus are obtained in the form of matrix inequalities. Finally, numerical simulations are given to illustrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

The exact computational problem of λ -constrained admissible average dwell time (CAADT) contractive set and CAADT invariant set for discrete-time switched systems with and without persistent amplitude-bounded additive disturbance is investigated in this paper. The considered switching signal satisfies average dwell time (ADT) and is discussed in terms of stage which is both length-based and sequence-based for the first time. Two more general criteria are established for checking the existence of the λ -average dwell time (ADT) contractive set and the ADT invariant set of the considered system by assuming the value of stage length is taken from an arbitrary finite set. A detailed discussion is included to identify a proper value for stage length by taking the computational complexity and the conservatism of the designed finite-step computational algorithms of the λ -CAADT contractive set and the CAADT invariant set into consideration. Some characteristics of the admissible λ -CAADT contractive set and CAADT invariant set are derived. An illustrative example illustrates the effectiveness of the developed results. [ABSTRACT FROM AUTHOR]

In this article, we find stability criteria for perturbed differential systems, in terms of two measures. Our main tool is a definition of total stability based on two classes of perturbations.

This paper addresses the problem of bounding the trajectories of nonlinear systems (transient and ultimate bounds) from initial conditions in given sets, when subject to possibly nonvanishing disturbances constrained by some finite-interval integral bounds, with a suitable controller. The so-called robustly-inescapable sets are determined from such initial conditions and disturbance bounds. In order to get numerical results, the approach considers embedding the nonlinear dynamics in a convex combination of polynomials, and solving sum-of-squares (SOS) problems on them, optimising some inescapable-set size parameters. Determination of approximate (locally) optimal solutions usually requires an iterative evaluation of SOS problems, because of products of decision variables. [ABSTRACT FROM AUTHOR]

This study is concerned with robust quasi‐min–max model predictive control (MPC) for a class of discrete‐time singular systems with persistent disturbance and input constrains. To deal with the persistent disturbance, the authors introduce the notion of input‐to‐state stability (ISS) of discrete‐time singular system for the first time. The optimal control can be obtained by solving a quasi‐min–max optimal problem of a finite horizon cost function. On the basis of the proposed dual‐mode MPC approach, it can be proved that the closed‐loop discrete‐time singular system is ISS, regular and causal. Finally, a numerical simulation shows the feasibility and effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In this article, we find stability criteria for perturbed differential systems, in terms of two measures. Our main tool is a definition of total stability based on two classes of perturbations. [ABSTRACT FROM AUTHOR]

This paper considers the problem of persistent bounded disturbance rejection for a class of time-delay systems with parametric uncertainty by Lyapunov function and positively invariant set analysis method. Sufficient conditions for internal stability and L1-performance analysis are given in terms of linear matrix inequalities (LMIs). Based on the results, a simple approach to the design of a linear state-feedback controller is presented to stabilize robustly the uncertain time-delay systems and achieve a desired level of disturbance attenuation. All the obtained conditions are delay dependent. A numerical example is included to illustrate the proposed method. [ABSTRACT FROM AUTHOR]

In this paper the new concepts of restricted total stability and total attractivity is formulated. For this purpose the classical theory of Malkin with suitable changes and the theory of limiting equations, introduced by Sell developed by Artstein and Andreev, are used. Significant examples are presented. [ABSTRACT FROM AUTHOR]