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Elimination of finite eigenvalues of the 2D Roesser model by state feedbacks

Tadeusz Kaczorek (2001)

International Journal of Applied Mathematics and Computer Science

A new problem of decreasing the degree of the closed-loop characteristic polynomial of the 2D Roesser model by a suitable choice of state feedbacks is formulated. Sufficient conditions are established under which it is possible to choose state feedbacks such that the non-zero closed-loop characteristic polynomial has degree zero. A procedure for computation of the feedback gain matrices is presented and illustrated by a numerical example.

Enlarged Asymptotic Compensation in Discrete Distributed Systems

L. Afifi, M. Hakam, M. Bahadi, A. El Jai (2010)

Mathematical Modelling of Natural Phenomena

This work concerns an enlarged analysis of the problem of asymptotic compensation for a class of discrete linear distributed systems. We study the possibility of asymptotic compensation of a disturbance by bringing asymptotically the observation in a given tolerance zone 𝒞. Under convenient hypothesis, we show the existence and the unicity of the optimal control ensuring this compensation and we give its characterization

Equivalent descriptions of a discrete-time fractional-order linear system and its stability domains

Piotr Ostalczyk (2012)

International Journal of Applied Mathematics and Computer Science

Two description forms of a linear fractional-order discrete system are considered. The first one is by a fractional-order difference equation, whereas the second by a fractional-order state-space equation. In relation to the two above-mentioned description forms, stability domains are evaluated. Several simulations of stable, marginally stable and unstable unit step responses of fractional-order systems due to different values of system parameters are presented.

Event monitoring of parallel computations

Alexander M. Gruzlikov, Nikolai V. Kolesov, Marina V. Tolmacheva (2015)

International Journal of Applied Mathematics and Computer Science

The paper considers the monitoring of parallel computations for detection of abnormal events. It is assumed that computations are organized according to an event model, and monitoring is based on specific test sequences.

Existence of different kind of solutions for discrete time equations

Denis Pennequin (2014)

Nonautonomous Dynamical Systems

The aim of this paper is to extend the classical linear condition concerning diagonal dominant bloc matrix to fully nonlinear equations. Even if assumptions are strong, we obtain an explicit condition which exactly extend the one known in linear case, and the setting allows also to consider bicontinuous operator instead of the schift and as particular case, we receive periodic or almost periodic solutions for discrete time equations.

Externally and internally positive singular discrete-time linear systems

Tadeusz Kaczorek (2002)

International Journal of Applied Mathematics and Computer Science

Notions of externally and internally positive singular discrete-time linear systems are introduced. It is shown that a singular discrete-time linear system is externally positive if and only if its impulse response matrix is non-negative. Sufficient conditions are established under which a single-output singular discrete-time system with matrices in canonical forms is internally positive. It is shown that if a singular system is weakly positive (all matrices E, A, B, C are non-negative), then it...

Falseness of the finiteness property of the spectral subradius

Adam Czornik, Piotr Jurgas (2007)

International Journal of Applied Mathematics and Computer Science

We prove that there exist infinitely may values of the real parameter α for which the exact value of the spectral subradius of the set of two matrices (one matrix with ones above and on the diagonal and zeros elsewhere, and one matrix with α below and on the diagonal and zeros elsewhere, both matrices having two rows and two columns) cannot be calculated in a finite number of steps. Our proof uses only elementary facts from the theory of formal languages and from linear algebra, but it is not constructive...

Fault diagnosis and fault tolerant control using set-membership approaches: Application to real case studies

Vicenç Puig (2010)

International Journal of Applied Mathematics and Computer Science

This paper reviews the use of set-membership methods in fault diagnosis (FD) and fault tolerant control (FTC). Setmembership methods use a deterministic unknown-but-bounded description of noise and parametric uncertainty (interval models). These methods aims at checking the consistency between observed and predicted behaviour by using simple sets to approximate the exact set of possible behaviour (in the parameter or the state space). When an inconsistency is detected between the measured and predicted...

Fault diagnosis of networked control systems

Christophe Aubrun, Dominique Sauter, Joseph Yamé (2008)

International Journal of Applied Mathematics and Computer Science

Networked Control Systems (NCSs) deal with feedback control systems with loops closed via data communication networks. Control over a network has many advantages compared with traditionally controlled systems, such as a lower implementation cost, reduced wiring, simpler installation and maintenance and higher reliability. Nevertheless, the networkinduced delay, packet dropout, asynchronous behavior and other specificities of networks will degrade the performance of closed-loop systems. In this context,...

Fault tolerance in networked control systems under intermittent observations

Jean-Philippe Georges, Didier Theilliol, Vincent Cocquempot, Jean-Christophe Ponsart, Christophe Aubrun (2011)

International Journal of Applied Mathematics and Computer Science

This paper presents an approach to fault tolerant control based on the sensor masking principle in the case of wireless networked control systems. With wireless transmission, packet losses act as sensor faults. In the presence of such faults, the faulty measurements corrupt directly the behaviour of closed-loop systems. Since the controller aims at cancelling the error between the measurement and its reference input, the real outputs will, in such a networked control system, deviate from the desired...

Flow control in connection-oriented networks: a time-varying sampling period system case study

Przemysław Ignaciuk, Andrzej Bartoszewicz (2008)

Kybernetika

In this paper congestion control problem in connection-oriented communication network with multiple data sources is addressed. In the considered network the feedback necessary for the flow regulation is provided by means of management units, which are sent by each source once every M data packets. The management units, carrying the information about the current network state, return to their origin round trip time RTT after they were sent. Since the source rate is adjusted only at the instant of...

Fopid Controller Design for Robust Performance Using Particle Swarm Optimization

Zamani, Majid, Karimi-Ghartemani, Masoud, Sadati, Nasser (2007)

Fractional Calculus and Applied Analysis

Mathematics Subject Classification: 26A33; 93C15, 93C55, 93B36, 93B35, 93B51; 03B42; 70Q05; 49N05This paper proposes a novel method to design an H∞ -optimal fractional order PID (FOPID) controller with ability to control the transient, steady-state response and stability margins characteristics. The method uses particle swarm optimization algorithm and operates based on minimizing a general cost function. Minimization of the cost function is carried out subject to the H∞ -norm; this norm is also...

Fractional kalman filter algorithm for the states parameters and order of fractional system estimation

Dominik Sierociuk, Andrzej Dzieliński (2006)

International Journal of Applied Mathematics and Computer Science

This paper presents a generalization of the Kalman filter for linear and nonlinear fractional order discrete state-space systems. Linear and nonlinear discrete fractional order state-space systems are also introduced. The simplified kalman filter for the linear case is called the fractional Kalman filter and its nonlinear extension is named the extended fractional Kalman filter. The background and motivations for using such techniques are given, and some algorithms are discussed. The paper also...

Functional observers design for nonlinear discrete-time systems with interval time-varying delays

Yali Dong, Laijun Chen, Shengwei Mei (2019)

Kybernetika

This paper is concerned with the functional observer design for a class of Multi-Input Multi-Output discrete-time systems with mixed time-varying delays. Firstly, using the Lyapunov-Krasovskii functional approach, we design the parameters of the delay-dependent observer. We establish the sufficient conditions to guarantee the exponential stability of functional observer error system. In addition, for design purposes, delay-dependent sufficient conditions are proposed in terms of matrix inequalities...

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