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On the Optimal Control of a Class of Time-Delay System

L. Boudjenah, M.F. Khelfi (2010)

Mathematical Modelling of Natural Phenomena

In this work we study the optimal control problem for a class of nonlinear time-delay systems via paratingent equation with delayed argument. We use an equivalence theorem between solutions of differential inclusions with time-delay and solutions of paratingent equations with delayed argument. We study the problem of optimal control which minimizes a certain cost function. To show the existence of optimal control, we use the main topological properties...

On the optimal control of coefficients in elliptic problems. Application to the optimization of the head slider

Ionel Ciuperca, Mohamed El Alaoui Talibi, Mohammed Jai (2005)

ESAIM: Control, Optimisation and Calculus of Variations

We consider an optimal control problem for a class of non-linear elliptic equations. A result of existence and uniqueness of the state equation is proven under weaker hypotheses than in the literature. We also prove the existence of an optimal control. Applications to some lubrication problems and numerical results are given.

On the optimal control of coefficients in elliptic problems. Application to the optimization of the head slider

Ionel Ciuperca, Mohamed El Alaoui Talibi, Mohammed Jai (2010)

ESAIM: Control, Optimisation and Calculus of Variations

We consider an optimal control problem for a class of non-linear elliptic equations. A result of existence and uniqueness of the state equation is proven under weaker hypotheses than in the literature. We also prove the existence of an optimal control. Applications to some lubrication problems and numerical results are given.

On the optimal control problem governed by the equations of von Kármán. II. Mixed boundary conditions

Igor Bock, Ivan Hlaváček, Ján Lovíšek (1985)

Aplikace matematiky

A control of the system of Kármán's equations for a thin elastic plate is considered. Existence of an optimal transversal load and optimal stress function, respectively, is proven. The set of admissible functions is chosen in a way guaranteeing the unique solvability of the state problem. The differentiability of the state function with respect to the control variable, uniqueness of the optimal control and some necessary conditions of optimality are discussed.

On the optimal control problem governed by the equations of von Kármán. I. The homogeneous Dirichlet boundary conditions

Igor Bock, Ivan Hlaváček, Ján Lovíšek (1984)

Aplikace matematiky

A control of the system of nonlinear Kármán's equations for a thin elastic plate with clamped edge is considered. The transversal loading plays the role of the control variable. The set of admissible controls is chosen in a way guaranteeing the unique solvability of the state function with respect to the control variable is proved. A disscussion of uniqueness of the optimal control and some necessary conditions of optimality are presented.

On the optimal control problem governed by the equations of von Kármán. III. The case of an arbitrary large perpendicular load

Igor Bock, Ivan Hlaváček, Ján Lovíšek (1987)

Aplikace matematiky

We shall deal with an optimal control problem for the deffection of a thin elastic plate. We consider the perpendicular load on the plate as the control variable. In contrast to the papers [1], [2], arbitrarily large loads are edmitted. As the unicity of a solution of the state equation is not guaranteed, we consider the cost functional defined on the set of admissible controls and states, and the state equation plays the role of the constraint. The existence of an optimal couple (i.e., control...

On the points of non-differentiability of convex functions

David Pavlica (2004)

Commentationes Mathematicae Universitatis Carolinae

We characterize sets of non-differentiability points of convex functions on n . This completes (in n ) the result by Zajíček [2] which gives a characterization of the magnitude of these sets.

On the quasiconvex exposed points

Kewei Zhang (2001)

ESAIM: Control, Optimisation and Calculus of Variations

The notion of quasiconvex exposed points is introduced for compact sets of matrices, motivated from the variational approach to material microstructures. We apply the notion to give geometric descriptions of the quasiconvex extreme points for a compact set. A weak version of Straszewicz type density theorem in convex analysis is established for quasiconvex extreme points. Some examples are examined by using known explicit quasiconvex functions.

On the quasiconvex exposed points

Kewei Zhang (2010)

ESAIM: Control, Optimisation and Calculus of Variations

The notion of quasiconvex exposed points is introduced for compact sets of matrices, motivated from the variational approach to material microstructures. We apply the notion to give geometric descriptions of the quasiconvex extreme points for a compact set. A weak version of Straszewicz type density theorem in convex analysis is established for quasiconvex extreme points. Some examples are examined by using known explicit quasiconvex functions.

On the reduction of pairs of bounded closed convex sets

J. Grzybowski, D. Pallaschke, R. Urbański (2008)

Studia Mathematica

Let X be a Hausdorff topological vector space. For nonempty bounded closed convex sets A,B,C,D ⊂ X we denote by A ∔ B the closure of the algebraic sum A + B, and call the pairs (A,B) and (C,D) equivalent if A ∔ D = B ∔ C. We prove two main theorems on reduction of equivalent pairs. The first theorem implies that, in a finite-dimensional space, a pair of nonempty compact convex sets with a piecewise smooth boundary and parallel tangent spaces at some boundary points is not minimal. The second theorem...

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