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Distributed control for multistate modified Navier-Stokes equations

Nadir Arada (2013)

ESAIM: Control, Optimisation and Calculus of Variations

The aim of this paper is to establish necessary optimality conditions for optimal control problems governed by steady, incompressible Navier-Stokes equations with shear-dependent viscosity. The main difficulty derives from the fact that equations of this type may exhibit non-uniqueness of weak solutions, and is overcome by introducing a family of approximate control problems governed by well posed generalized Stokes systems and by passing to the limit in the corresponding optimality conditions.

Div-curl Young measures and optimal design in any dimension.

Pablo Pedregal (2007)

Revista Matemática Complutense

We explicitly introduce and exploit div-curl Young measures to examine optimal design problems governed by a linear state law in divergence form. The cost is allowed to depend explicitly on the gradient of the state. By means of this family of measures, we can formulate a suitable relaxed version of the problem, and, in a subsequent step, put it in a similar form as the original optimal design problem with an appropriate set of designs and generalized state law. Many of the issues involved has been...

Domain optimization in 3 D -axisymmetric elliptic problems by dual finite element method

Ivan Hlaváček (1990)

Aplikace matematiky

An axisymmetric second order elliptic problem with mixed boundary conditions is considered. The shape of the domain has to be found so as to minimize a cost functional, which is given in terms of the cogradient of the solution. A new dual finite element method is used for approximate solutions. The existence of an optimal domain is proven and a convergence analysis presented.

Domaine de victoire et stratégies viables chez les pêcheurs décrits par l'anthropologue Fredrik Barth

Noël Bonneuil, Patrick Saint-Pierre (1998)

Mathématiques et Sciences Humaines

L'anthropologue Fredrik Barth a analysé l'émergence des formes sociales chez les pêcheurs norvégiens. Sa perspective est bien modélisée par les outils mathématiques de la théorie de la viabilité, grâce auxquels on peut calculer l'ensemble des états à partir desquels la survie du système est encore possible, ainsi que la bonne décision à prendre à chaque instant, entre explorer ou suivre les autres bateaux. En outre, il se trouve que, techniquement, la condition de compacité des images de la correspondance...

Doubles limites ordonnées et théorèmes de minimax

Marc De Wilde (1974)

Annales de l'institut Fourier

On introduit une variante des “doubles limites interchangeables” de Grothendieck, les “doubles limites ordonnées” et on en déduit un théorème de maximinimax. En introduisant des conditions de convexité convenables, on transforme celui-ci en un théorème de minimax. Ces résultats permettant de retrouver de façon simple un théorème de maximinimax de Simons.

Double-stepped adaptive control for hybrid systems with unknown Markov jumps and stochastic noises

Shuping Tan, Ji-Feng Zhang (2009)

ESAIM: Control, Optimisation and Calculus of Variations

This paper is concerned with the sampled-data based adaptive linear quadratic (LQ) control of hybrid systems with both unmeasurable Markov jump processes and stochastic noises. By the least matching error estimation algorithm, parameter estimates are presented. By a double-step (DS) sampling approach and the certainty equivalence principle, a sampled-data based adaptive LQ control is designed. The DS-approach is characterized by a comparatively large estimation step for parameter estimation and...

Double-stepped adaptive control for hybrid systems with unknown Markov jumps and stochastic noises

Shuping Tan, Ji-Feng Zhang (2008)

ESAIM: Control, Optimisation and Calculus of Variations

This paper is concerned with the sampled-data based adaptive linear quadratic (LQ) control of hybrid systems with both unmeasurable Markov jump processes and stochastic noises. By the least matching error estimation algorithm, parameter estimates are presented. By a double-step (DS) sampling approach and the certainty equivalence principle, a sampled-data based adaptive LQ control is designed. The DS-approach is characterized by a comparatively large estimation step for parameter estimation and...

Doubly reflected BSDEs with call protection and their approximation

Jean-François Chassagneux, Stéphane Crépey (2014)

ESAIM: Probability and Statistics

We study the numerical approximation of doubly reflected backward stochastic differential equations with intermittent upper barrier (RIBSDEs). These denote reflected BSDEs in which the upper barrier is only active on certain random time intervals. From the point of view of financial interpretation, RIBSDEs arise as pricing equations of game options with constrained callability. In a Markovian set-up we prove a convergence rate for a time-discretization scheme by simulation to an RIBSDE. We also...

Dualidad de Haar y problemas de momentos.

Miguel Angel Goberna Torrent (1986)

Trabajos de Investigación Operativa

En la primera parte de este trabajo damos una versión simplificada de la conocida relación entre la dualidad en Programación Semi-Infinita y cierta clase de problemas de momentos, basándonos en las propiedades de los sistemas de Farkas-Minkowski. Planteamos a continuación otra clase de problemas de momentos para cuyo análisis resulta de utilidad una generalización del Lema de Farkas.

Dualidad en la programación lineal en subconjuntos difusos.

José Llena Sitjes (1988)

Trabajos de Investigación Operativa

La programación lineal sobre subconjuntos difusos, definida por Zimmermann, se desarrolla en estrecha relación con la definición de las funciones pertinentes funciones de pertenencia. Se estudia la dualidad difusa, ligada a la dualidad en los problemas de programación lineal con multicriterios.

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