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Strong-weak Stackelberg Problems in Finite Dimensional Spaces

Aboussoror, Abdelmalek, Loridan, Pierre (1995)

Serdica Mathematical Journal

We are concerned with two-level optimization problems called strongweak Stackelberg problems, generalizing the class of Stackelberg problems in the strong and weak sense. In order to handle the fact that the considered two-level optimization problems may fail to have a solution under mild assumptions, we consider a regularization involving ε-approximate optimal solutions in the lower level problems. We prove the existence of optimal solutions for such regularized problems and present some approximation...

Structural discontinuities to approximate some optimization problems with a nonmonotone impulsive character

Aldo Bressan, Monica Motta (1995)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

In some preceding works we consider a class O P of Boltz optimization problems for Lagrangian mechanical systems, where it is relevant a line l = l γ ( ) , regarded as determined by its (variable) curvature function γ ( ) of domain s 0 , s 1 . Assume that the problem P ~ O P is regular but has an impulsive monotone character in the sense that near each of some points δ 1 to δ ν γ ( ) is monotone and | γ ( ) | is very large. In [10] we propose a procedure belonging to the theory of impulsive controls, in order to simplify P ~ into a structurally...

Structural Properties of Solutions to Total Variation Regularization Problems

Wolfgang Ring (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

In dimension one it is proved that the solution to a total variation-regularized least-squares problem is always a function which is "constant almost everywhere" , provided that the data are in a certain sense outside the range of the operator to be inverted. A similar, but weaker result is derived in dimension two.

Structure of stable solutions of a one-dimensional variational problem

Nung Kwan Yip (2006)

ESAIM: Control, Optimisation and Calculus of Variations

We prove the periodicity of all H2-local minimizers with low energy for a one-dimensional higher order variational problem. The results extend and complement an earlier work of Stefan Müller which concerns the structure of global minimizer. The energy functional studied in this work is motivated by the investigation of coherent solid phase transformations and the competition between the effects from regularization and formation of small scale structures. With a special choice of a bilinear double...

Study of a contact problem with normal compliance and nonlocal friction

Arezki Touzaline (2012)

Applicationes Mathematicae

We consider a static frictional contact between a nonlinear elastic body and a foundation. The contact is modelled by a normal compliance condition such that the penetration is restricted with unilateral constraint and associated to the nonlocal friction law. We derive a variational formulation and prove its unique weak solvability if the friction coefficient is sufficiently small. Moreover, we prove the continuous dependence of the solution on the contact conditions. Also we study the finite element...

Study of a viscoelastic frictional contact problem with adhesion

Arezki Touzaline (2011)

Commentationes Mathematicae Universitatis Carolinae

We consider a quasistatic frictional contact problem between a viscoelastic body with long memory and a deformable foundation. The contact is modelled with normal compliance in such a way that the penetration is limited and restricted to unilateral constraint. The adhesion between contact surfaces is taken into account and the evolution of the bonding field is described by a first order differential equation. We derive a variational formulation and prove the existence and uniqueness result of the...

Su alcune proprietà delle funzioni convesse

Luigi Ambrosio (1992)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

In questo lavoro riassumiamo alcuni risultati di una ricerca riguardante le singolarità (punti di non differenziabilità) delle funzioni convesse. Questa ricerca copre vari aspetti, che vanno dalla stima della dimensione di Hausdorff di certi tipi di singolarità fino allo studio della loro propagazione. Studiamo anche problemi di semicontinuità e rilassamento collegati all'area del grafico del gradiente di una funzione convessa e l'esistenza dei determinanti, in senso debole, dei minori della matrice...

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