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A necessary and sufficient condition for decentralized control of discrete event systems via prioritized composition with exclusion (PCX) is provided. PCX was extended from prioritized synchronous composition (PSC) in order to model various Boolean modes of decision fusion by allowing the exclusivity of participation in system interactions [1]. A notion of PCX-coobservability is introduced that captures the nature of PCX-based decision fusion, and a testing algorithm with polynomial complexity in the states of plant and specification is presented. The result is extended for multiple supervisors with multiple exclusivity sets based on an extended PCX definition. [ABSTRACT FROM AUTHOR]

In conservative (or complete) trace-based distributed fault diagnosis it is common to compute, for each component, a preliminary local estimate consisting of all possible traces that can generate the same local symptom (i.e., a collection of sequences of observable events) as the one being received from that component up to a specific time instant. Then communication among local trace estimators can be used to refine those preliminary local estimates. An approach has been proposed by Su and Wonham to perform such refinement in terms of achieving global or local consistency among local estimates. But that approach does not consider timing mismatch and channel distortion in the process of collecting local symptoms, which may result in incorrect estimates in practical applications. In this paper, we will provide a new approach to handle trace estimation under timing mismatch and channel distortion. [ABSTRACT FROM AUTHOR]

This study employs the free-weighting matrix approach to investigate the output feedback control of a linear discrete-time system with an interval time-varying delay. First, the delay-dependent stability is analyzed using a new method of estimating the upper bound on the difference of a Lyapunov function without ignoring any terms; and based on the results, a design criterion for a static output feedback (SOF) controller is derived. Since the conditions thus obtained for the existence of admissible controllers are not expressed strictly in terms of linear matrix inequalities, a modified cone complementarity linearization algorithm is employed to solve the nonconvex feasibility SOF control problem. Furthermore, the problem of designing a dynamic output feedback controller is formulated as one of designing an SOF controller. Numerical examples demonstrate the effectiveness of the method and its advantage over existing methods. [ABSTRACT FROM AUTHOR]

This work proposes a technique for the design of stabilizing dynamic output feedback controllers for discrete-time linear systems with rate and amplitude saturating actuators. The nonlinear effects introduced by the saturations in the closed-loop system are taken into account by using a generalized sector condition, which leads to theoretical conditions for solving the problem directly in the form of linear matrix inequalities. [ABSTRACT FROM AUTHOR]

This paper investigates the stabilizability of uncertain linear time-invariant (LTI) systems via structurally constrained controllers. First, an LTI uncertain system is considered whose state-space matrices depend polynomially on the uncertainty vector, defined over some region. It is shown that if the system is stabilizable by a structurally constrained controller in one point belonging to the region, then it is stabilizable by a controller with the same structure in all points belonging to the region, except for those located on an algebraic variety. Thus, if a system is stabilizable via a constrained controller at the nominal point, then it is almost always stabilizable at any operating point around the nominal model. It is also shown how this algebraic variety (or the dominant subvariety of it) can be computed efficiently. The results obtained in this paper encompass a broad range of the existing results in the literature on robust stability of the LTI systems, in addition to new ones. [ABSTRACT FROM AUTHOR]

This paper describes the computation of reach sets for discrete-time linear control systems with time-varying coefficients and ellipsoidal bounds on the controls and initial conditions. The algorithms construct external and internal ellipsoidal approximations that touch the reach set boundary from outside and from in- side. Recurrence relations describe the time evolution of these approximations. An essential part of the paper deals with singular discrete-time linear systems. [ABSTRACT FROM AUTHOR]

This note deals with the state reconstruction of a class of discrete-time systems with time-varying parameters. While usually, the parameters are assumed to be online available and exactly known, the special and realistic situation when the parameters are known with a finite accuracy is considered. The main objective of the note is to show that, despite of the resulting mismatch between the true system and the model, the state reconstruction error boundedness can be guaranteed and an explicit bound can be derived. The proof is based upon the concept of input-to-state stability. [ABSTRACT FROM AUTHOR]