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On the lower semicontinuity of supremal functionals

Michele Gori, Francesco Maggi (2003)

ESAIM: Control, Optimisation and Calculus of Variations

In this paper we study the lower semicontinuity problem for a supremal functional of the form F ( u , Ω ) = ess sup x Ω f ( x , u ( x ) , D u ( x ) ) with respect to the strong convergence in L ( Ω ) , furnishing a comparison with the analogous theory developed by Serrin for integrals. A sort of Mazur’s lemma for gradients of uniformly converging sequences is proved.

On the Lower Semicontinuity of Supremal Functionals

Michele Gori, Francesco Maggi (2010)

ESAIM: Control, Optimisation and Calculus of Variations

In this paper we study the lower semicontinuity problem for a supremal functional of the form F ( u , Ω ) = ess sup x Ω f ( x , u ( x ) , D u ( x ) ) with respect to the strong convergence in L∞(Ω), furnishing a comparison with the analogous theory developed by Serrin for integrals. A sort of Mazur's lemma for gradients of uniformly converging sequences is proved.

On the lower semicontinuous quasiconvex envelope for unbounded integrands (I)

Marcus Wagner (2009)

ESAIM: Control, Optimisation and Calculus of Variations

Motivated by the study of multidimensional control problems of Dieudonné-Rashevsky type, we raise the question how to understand to notion of quasiconvexity for a continuous function f with a convex body K n m instead of the whole space n m as the range of definition. In the present paper, we trace the consequences of an infinite extension of f outside K, and thus study quasiconvex functions which are allowed to take the value +∞. As an appropriate envelope, we introduce and investigate the lower semicontinuous...

On the Łojasiewicz exponent at infinity of real polynomials

Ha Huy Vui, Pham Tien Son (2008)

Annales Polonici Mathematici

Let f: ℝⁿ → ℝ be a nonconstant polynomial function. Using the information from the "curve of tangency" of f, we provide a method to determine the Łojasiewicz exponent at infinity of f. As a corollary, we give a computational criterion to decide if the Łojasiewicz exponent at infinity is finite or not. Then we obtain a formula to calculate the set of points at which the polynomial f is not proper. Moreover, a relation between the Łojasiewicz exponent at infinity of f and the problem of computing...

On the minimum of the work of interaction forces between a pseudoplate and a rigid obstacle

Igor Bock, Ján Lovíšek (2001)

Mathematica Bohemica

An optimization problem for the unilateral contact between a pseudoplate and a rigid obstacle is considered. The variable thickness of the pseudoplate plays the role of a control variable. The cost functional is a regular functional only in the smooth case. The existence of an optimal thickness is verified. The penalized optimal control problem is considered in the general case.

On the Newton partially flat minimal resistance body type problems

M. Comte, Jesus Ildefonso Díaz (2005)

Journal of the European Mathematical Society

We study the flat region of stationary points of the functional Ω F ( | u ( x ) | ) d x under the constraint u M , where Ω is a bounded domain in 2 . Here F ( s ) is a function which is concave for s small and convex for s large, and M > 0 is a given constant. The problem generalizes the classical minimal resistance body problems considered by Newton. We construct a family of partially flat radial solutions to the associated stationary problem when Ω is a ball. We also analyze some other qualitative properties. Moreover, we show the...

On the notion of Jacobi fields in constrained calculus of variations

Enrico Massa, Enrico Pagani (2016)

Communications in Mathematics

In variational calculus, the minimality of a given functional under arbitrary deformations with fixed end-points is established through an analysis of the so called second variation. In this paper, the argument is examined in the context of constrained variational calculus, assuming piecewise differentiable extremals, commonly referred to as extremaloids. The approach relies on the existence of a fully covariant representation of the second variation of the action functional, based on a family of...

On the numerical modeling of deformations of pressurized martensitic thin films

Pavel Bělík, Timothy Brule, Mitchell Luskin (2001)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

We propose, analyze, and compare several numerical methods for the computation of the deformation of a pressurized martensitic thin film. Numerical results have been obtained for the hysteresis of the deformation as the film transforms reversibly from austenite to martensite.

On the Numerical Modeling of Deformations of Pressurized Martensitic Thin Films

Pavel Bělík, Timothy Brule, Mitchell Luskin (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

We propose, analyze, and compare several numerical methods for the computation of the deformation of a pressurized martensitic thin film. Numerical results have been obtained for the hysteresis of the deformation as the film transforms reversibly from austenite to martensite.

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