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Geometrical aspects of exact boundary controllability for the wave equation - a numerical study

M. Asch, G. Lebeau (2010)

ESAIM: Control, Optimisation and Calculus of Variations

This essentially numerical study, sets out to investigate various geometrical properties of exact boundary controllability of the wave equation when the control is applied on a part of the boundary. Relationships between the geometry of the domain, the geometry of the controlled boundary, the time needed to control and the energy of the control are dealt with. A new norm of the control and an energetic cost factor are introduced. These quantities enable a detailed appraisal of the numerical solutions...

Geometrical characterization of observability in Interpreted Petri Nets

Israel Rivera-Rangel, Antonio Ramírez-Treviño, Luis I. Aguirre-Salas, Javier Ruiz (2005)

Kybernetika

This work is concerned with observability in Discrete Event Systems (DES) modeled by Interpreted Petri Nets (IPN). Three major contributions are presented. First, a novel geometric characterization of observability based on input-output equivalence relations on the marking sequences sets is presented. Later, to show that this characterization is well posed, it is applied to linear continuous systems, leading to classical characterizations of observability for continuous systems. Finally, this paper...

Global Carleman estimate for stochastic parabolic equations, and its application

Xu Liu (2014)

ESAIM: Control, Optimisation and Calculus of Variations

This paper is addressed to proving a new Carleman estimate for stochastic parabolic equations. Compared to the existing Carleman estimate in this respect (see [S. Tang and X. Zhang, SIAM J. Control Optim. 48 (2009) 2191–2216.], Thm. 5.2), one extra gradient term involving in that estimate is eliminated. Also, our improved Carleman estimate is established by virtue of the known Carleman estimate for deterministic parabolic equations. As its application, we prove the existence of insensitizing controls...

Global controllability and stabilization for the nonlinear Schrödinger equation on an interval

Camille Laurent (2010)

ESAIM: Control, Optimisation and Calculus of Variations

We prove global internal controllability in large time for the nonlinear Schrödinger equation on a bounded interval with periodic, Dirichlet or Neumann conditions. Our strategy combines stabilization and local controllability near 0. We use Bourgain spaces to prove this result on L2. We also get a regularity result about the control if the data are assumed smoother.

Global controllability properties for the semilinear heat equation with superlinear term.

A. Y. Khapalov (1999)

Revista Matemática Complutense

We discuss several global approximate controllability properties for the semilinear heat equation with superlinear reaction-convection term, governed in a bounded domain by locally distributed controls. First, based on the asymptotic analysis in vanishing time, we study the steering of the projections of its solution on any finite dimensional space spanned by the eigenfunctions for the truncated linear part. We show that, if the control-supporting area is properly chosen, then they can approximately...

Global finite-time observers for a class of nonlinear systems

Yunyan Li, Yanjun Shen, Xiao Hua Xia (2013)

Kybernetika

Global finite-time observers are designed for a class of nonlinear systems with bounded varying rational powers imposed on the increments of the nonlinearities whose solutions exist and are unique for all positive time. The global finite-time observers designed in this paper are with two homogeneous terms. The global finite-time convergence of the observation error system is achieved by combining global asymptotic stability and local finite-time stability.

Global linearization of nonlinear systems - A survey

Sergej Čelikovský (1995)

Banach Center Publications

A survey of the global linearization problem is presented. Known results are divided into two groups: results for general affine nonlinear systems and for bilinear systems. In the latter case stronger results are available. A comparision of various linearizing transformations is performed. Numerous illustrative examples are included.

Global non-negative controllability of the semilinear parabolic equation governed by bilinear control

Alexander Y. Khapalov (2002)

ESAIM: Control, Optimisation and Calculus of Variations

We study the global approximate controllability of the one dimensional semilinear convection-diffusion-reaction equation governed in a bounded domain via the coefficient (bilinear control) in the additive reaction term. Clearly, even in the linear case, due to the maximum principle, such system is not globally or locally controllable in any reasonable linear space. It is also well known that for the superlinear terms admitting a power growth at infinity the global approximate controllability by...

Global non-negative controllability of the semilinear parabolic equation governed by bilinear control

Alexander Y. Khapalov (2010)

ESAIM: Control, Optimisation and Calculus of Variations

We study the global approximate controllability of the one dimensional semilinear convection-diffusion-reaction equation governed in a bounded domain via the coefficient (bilinear control) in the additive reaction term. Clearly, even in the linear case, due to the maximum principle, such system is not globally or locally controllable in any reasonable linear space. It is also well known that for the superlinear terms admitting a power growth at infinity the global approximate controllability by...

Global stability of linearizing control with a new robust nonlinear observer of the induction motor

Mohammed Chenafa, Abdellah Mansouri, Abderrahmane Bouhenna, Eric Etien, Abdelkader Belaidi, Mouloud Denai (2005)

International Journal of Applied Mathematics and Computer Science

This paper mainly deals with the design of an advanced control law with an observer for a special class of nonlinear systems. We design an observer with a gain as a function of speed. We study the solution to the output feedback torque and rotor flux-tracking problem for an induction motor model given in the natural frame. We propose a new robust nonlinear observer and prove the global stability of the interlaced controller-observer system. The control algorithm is studied through simulations and...

Globality in semisimple Lie groups

Karl-Hermann Neeb (1990)

Annales de l'institut Fourier

In the first section of this paper we give a characterization of those closed convex cones (wedges) W in the Lie algebra s l ( 2 , R ) n which are invariant under the maximal compact subgroup of the adjoint group and which are controllable in the associated simply connected Lie group S l ( 2 , R ) n , i.e., for which the subsemigroup S = ( exp W ) generated by the exponential image of W agrees with the whole group G (Theorem 13). In Section 2 we develop some algebraic tools concerning real root decompositions with respect to compactly...

Gradient observability for diffusion systems

El Hassane Zerrik, Hamid Bourray (2003)

International Journal of Applied Mathematics and Computer Science

The aim of this paper is to study regional gradient observability for a diffusion system and the reconstruction of the state gradient without the knowledge of the state. First, we give definitions and characterizations of these new concepts and establish necessary conditions for the sensor structure in order to obtain regional gradient observability. We also explore an approach which allows for a regional gradient reconstruction. The developed method is original and leads to a numerical algorithm...

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