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Indirect stabilization of locally coupled wave-type systems

Fatiha Alabau-Boussouira, Matthieu Léautaud (2012)

ESAIM: Control, Optimisation and Calculus of Variations

We study in an abstract setting the indirect stabilization of systems of two wave-like equations coupled by a localized zero order term. Only one of the two equations is directly damped. The main novelty in this paper is that the coupling operator is not assumed to be coercive in the underlying space. We show that the energy of smooth solutions of these systems decays polynomially at infinity, whereas it is known that exponential stability does not...

Indirect stabilization of locally coupled wave-type systems

Fatiha Alabau-Boussouira, Matthieu Léautaud (2012)

ESAIM: Control, Optimisation and Calculus of Variations

We study in an abstract setting the indirect stabilization of systems of two wave-like equations coupled by a localized zero order term. Only one of the two equations is directly damped. The main novelty in this paper is that the coupling operator is not assumed to be coercive in the underlying space. We show that the energy of smooth solutions of these systems decays polynomially at infinity, whereas it is known that exponential stability does not...

Infinite time regular synthesis

B. Piccoli (2010)

ESAIM: Control, Optimisation and Calculus of Variations

In this paper we provide a new sufficiency theorem for regular syntheses. The concept of regular synthesis is discussed in [12], where a sufficiency theorem for finite time syntheses is proved. There are interesting examples of optimal syntheses that are very regular, but whose trajectories have time domains not necessarily bounded. The regularity assumptions of the main theorem in [12] are verified by every piecewise smooth feedback control generating extremal trajectories that reach the target...

Infinite-dimensional LMI approach to analysis and synthesis for linear time-delay systems

Kojiro Ikeda, Takehito Azuma, Kenko Uchida (2001)

Kybernetika

This paper considers an analysis and synthesis problem of controllers for linear time-delay systems in the form of delay-dependent memory state feedback, and develops an Linear Matrix Inequality (LMI) approach. First, we present an existence condition and an explicit formula of controllers, which guarantee a prescribed level of L 2 gain of closed loop systems, in terms of infinite-dimensional LMIs. This result is rather general in the sense that it covers, as special cases, some known results for...

Infinite-dimensional Sylvester equations: Basic theory and application to observer design

Zbigniew Emirsajłow (2012)

International Journal of Applied Mathematics and Computer Science

This paper develops a mathematical framework for the infinite-dimensional Sylvester equation both in the differential and the algebraic form. It uses the implemented semigroup concept as the main mathematical tool. This concept may be found in the literature on evolution equations occurring in mathematics and physics and is rather unknown in systems and control theories. But it is just systems and control theory where Sylvester equations widely appear, and for this reason we intend to give a mathematically...

Ingham-type inequalities and Riesz bases of divided differences

Sergei Avdonin, William Moran (2001)

International Journal of Applied Mathematics and Computer Science

We study linear combinations of exponentials e^{iλ_nt} , λ_n ∈ Λ in the case where the distance between some points λ_n tends to zero. We suppose that the sequence Λ is a finite union of uniformly discrete sequences. In (Avdonin and Ivanov, 2001), necessary and sufficient conditions were given for the family of divided differences of exponentials to form a Riesz basis in space L^2 (0,T). Here we prove that if the upper uniform density of Λ is less than T/(2π), the family of divided differences can...

Input constraints handling in an MPC/feedback linearization scheme

Jiamei Deng, Victor M. Becerra, Richard Stobart (2009)

International Journal of Applied Mathematics and Computer Science

The combination of model predictive control based on linear models (MPC) with feedback linearization (FL) has attracted interest for a number of years, giving rise to MPC+FL control schemes. An important advantage of such schemes is that feedback linearizable plants can be controlled with a linear predictive controller with a fixed model. Handling input constraints within such schemes is difficult since simple bound contraints on the input become state dependent because of the nonlinear transformation...

Input reconstruction by means of system inversion: A geometric approach to fault detection and isolation in nonlinear systems

András Edelmayer, József Bokor, Zoltán Szabó, Ferenc Szigeti (2004)

International Journal of Applied Mathematics and Computer Science

In this paper the classical detection filter design problem is considered as an input reconstruction problem. Input reconstruction is viewed as a dynamic inversion problem. This approach is based on the existence of the left inverse and arrives at detector architectures whose outputs are the fault signals while the inputs are the measured system inputs and outputs and possibly their time derivatives. The paper gives a brief summary of the properties and existence of the inverse for linear and nonlinear...

Input to state stability properties of nonlinear systems and applications to bounded feedback stabilization using saturation

J. Tsinias (2010)

ESAIM: Control, Optimisation and Calculus of Variations

The concepts of stability, attractivity and asymptotic stability for systems subject to restrictions of the input values are introduced and analyzed in terms of Lyapunov functions. A comparison with the well known input-to-state stability property introduced by Sontag is provided. We use these concepts in order to derive sufficient conditions for global stabilization for triangular and feedforward systems by means of saturated bounded feedback controllers and also recover some recent results...

Input-output decoupling of nonlinear recursive systems

Ülle Kotta (2000)

Kybernetika

The input-output decoupling problem is studied for a class of recursive nonlinear systems (RNSs), i. e. for systems, modelled by higher order nonlinear difference equations, relating the input, the output and a finite number of their time shifts. The solution of the problem via regular static feedback known for discrete-time nonlinear systems in state space form, is extended to RNSs. Necessary and sufficient conditions for local solvability of the problem are proposed. This is the alternative to...

Integral control of infinite-dimensional systems in the presence of hysteresis: an input-output approach

Hartmut Logemann, Eugene P. Ryan, Ilya Shvartsman (2007)

ESAIM: Control, Optimisation and Calculus of Variations

This paper is concerned with integral control of systems with hysteresis. Using an input-output approach, it is shown that application of integral control to the series interconnection of either (a) a hysteretic input nonlinearity, an L2-stable, time-invariant linear system and a non-decreasing globally Lipschitz static output nonlinearity, or (b) an L2-stable, time-invariant linear system and a hysteretic output nonlinearity, guarantees, under certain assumptions, tracking of constant reference...

Integral equations and time varying linear systems.

Lucas Jódar (1986)

Stochastica

In this paper we study the resolution problem of an integral equation with operator valued kernel. We prove the equivalence between this equation and certain time varying linear operator system. Sufficient conditions for solving the problem and explicit expressions of the solutions are given.

Integrated Design of an Active Flow Control System Using a Time-Dependent Adjoint Method

E.J. Nielsen, W.T. Jones (2011)

Mathematical Modelling of Natural Phenomena

An exploratory study is performed to investigate the use of a time-dependent discrete adjoint methodology for design optimization of a high-lift wing configuration augmented with an active flow control system. The location and blowing parameters associated with a series of jet actuation orifices are used as design variables. In addition, a geometric parameterization scheme is developed to provide a compact set of design variables describing the wing...

Integrated design of observer based fault detection for a class of uncertain nonlinear systems

Wei Chen, Abdul Q. Khan, Muhammmad Abid, Steven X. Ding (2011)

International Journal of Applied Mathematics and Computer Science

Integrated design of observer based Fault Detection (FD) for a class of uncertain nonlinear systems with Lipschitz nonlinearities is studied. In the context of norm based residual evaluation, the residual generator and evaluator are designed together in an integrated form, and, based on it, a trade-off FD system is finally achieved in the sense that, for a given Fault Detection Rate (FDR), the False Alarm Rate (FAR) is minimized. A numerical example is given to illustrate the effectiveness of the...

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