Null controllability of nonlinear infinite neutral system
Null controllability of semilinear degenerate parabolic equations in bounded domains.
Null controllability of some impulsive evolution equation in a Hilbert space.
Null controllability of the complex Ginzburg-Landau equation
Null controllability of the heat equation in unbounded domains by a finite measure control region
Motivated by two recent works of Micu and Zuazua and Cabanillas, De Menezes and Zuazua, we study the null controllability of the heat equation in unbounded domains, typically or . Considering an unbounded and disconnected control region of the form , we prove two null controllability results: under some technical assumption on the control parts , we prove that every initial datum in some weighted space can be controlled to zero by usual control functions, and every initial datum in can...
Null controllability of the heat equation in unbounded domains by a finite measure control region
Motivated by two recent works of Micu and Zuazua and Cabanillas, De Menezes and Zuazua, we study the null controllability of the heat equation in unbounded domains, typically or . Considering an unbounded and disconnected control region of the form , we prove two null controllability results: under some technical assumption on the control parts , we prove that every initial datum in some weighted L2 space can be controlled to zero by usual control functions, and every initial datum in L2(Ω)...
Null controllability of the heat equation with boundary Fourier conditions: the linear case
In this paper, we prove the global null controllability of the linear heat equation completed with linear Fourier boundary conditions of the form . We consider distributed controls with support in a small set and nonregular coefficients . For the proof of null controllability, a crucial tool will be a new Carleman estimate for the weak solutions of the classical heat equation with nonhomogeneous Neumann boundary conditions.
Null controllability of the semilinear heat equation
Null controllability of the semilinear heat equation
This paper is concerned with the null controllability of systems governed by semilinear parabolic equations. The control is exerted either on a small subdomain or on a portion of the boundary. We prove that the system is null controllable when the nonlinear term f(s) grows slower than s . log|s| as |s| → ∞.
Null exact controllability of the parabolic equations with equivalued surface boundary condition.
Null-control and measurable sets
We prove the interior and boundary null-controllability of some parabolic evolutions with controls acting over measurable sets.
Null-controllability of one-dimensional parabolic equations
We prove the interior null-controllability of one-dimensional parabolic equations with time independent measurable coefficients.
Null-controllability of some systems of parabolic type by one control force
We study the null controllability by one control force of some linear systems of parabolic type. We give sufficient conditions for the null controllability property to be true and, in an abstract setting, we prove that it is not always possible to control.
Null-controllability of some systems of parabolic type by one control force
We study the null controllability by one control force of some linear systems of parabolic type. We give sufficient conditions for the null controllability property to be true and, in an abstract setting, we prove that it is not always possible to control.
Numerical algorithm for nonsmooth stabilization of triangular form systems
Numerical analysis and systems theory
The area of numerical analysis interacts with the area of control and systems theory in a number of ways, some of which are widely recognized and some of which are not fully appreciated or understood. This paper will briefly discuss some of these areas of interaction and place the papers in this volume in context.
Numerical controllability of the wave equation through primal methods and Carleman estimates
This paper deals with the numerical computation of boundary null controls for the 1D wave equation with a potential. The goal is to compute approximations of controls that drive the solution from a prescribed initial state to zero at a large enough controllability time. We do not apply in this work the usual duality arguments but explore instead a direct approach in the framework of global Carleman estimates. More precisely, we consider the control that minimizes over the class of admissible null...
Numerical identification of a coefficient in a parabolic quasilinear equation
In the article the following optimal control problem is studied: to determine a certain coefficient in a quasilinear partial differential equation of parabolic type so that the solution of a boundary value problem for this equation would minimise a given integral functional. In addition to the design and analysis of a numerical method the paper contains the solution of the fundamental problems connected with the formulation of the problem in question (existence and uniqueness of the solution of...
Numerical operations among rational matrices: standard techniques and interpolation
Numerical operations on and among rational matrices are traditionally handled by direct manipulation with their scalar entries. A new numerically attractive alternative is proposed here that is based on rational matrix interpolation. The procedure begins with evaluation of rational matrices in several complex points. Then all the required operations are performed consecutively on constant matrices corresponding to each particular point. Finally, the resulting rational matrix is recovered from the...
Numerical studies of parameter estimation techniques for nonlinear evolution equations
We briefly discuss an abstract approximation framework and a convergence theory of parameter estimation for a general class of nonautonomous nonlinear evolution equations. A detailed discussion of the above theory has been given earlier by the authors in another paper. The application of this theory together with numerical results indicating the feasibility of this general least squares approach are presented in the context of quasilinear reaction diffusion equations.