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Convex approximation of an inhomogeneous anisotropic functional

Giovanni Bellettini, Maurizio Paolini (1994)

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

The numerical minimization of the functional F u = Ω ϕ x , ν u D u + Ω μ u d H n - 1 - Ω κ u d x , u B V Ω ; - 1 , 1 is addressed. The function ϕ is continuous, has linear growth, and is convex and positively homogeneous of degree one in the second variable. We prove that F can be equivalently minimized on the convex set B V Ω ; - 1 , 1 and then regularized with a sequence F ϵ u ϵ , of stricdy convex functionals defined on B V Ω ; - 1 , 1 . Then both F and F ϵ , can be discretized by continuous linear finite elements. The convexity property of the functionals on B V Ω ; - 1 , 1 is useful in the numerical minimization...

Convex approximations of functionals with curvature

Giovanni Bellettini, Maurizio Paolini, Claudio Verdi (1991)

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

We address the numerical minimization of the functional F v = Ω D v + Ω μ v d H n - 1 - Ω x v d x , for v B V Ω ; - 1 , 1 . We note that F can be equivalently minimized on the larger, convex, set B V Ω ; - 1 , 1 and that, on that space, F may be regularized with a sequence { F ϵ ( v ) = Ω ϵ 2 + D v 2 + Ω μ v d H n - 1 - Ω x v d x } ϵ of regular functionals. Then both F and F ϵ can be discretized by continuous linear finite elements. The convexity of the functionals in B V Ω ; - 1 , 1 is useful for the numerical minimization of F . We prove the Γ - L 1 Ω -convergence of the discrete functionals to F and present a few numerical examples.

Convex Hull Property and Exclosure Theorems for H-Minimal Hypersurfaces in Carnot Groups

Francescopaolo Montefalcone (2016)

Analysis and Geometry in Metric Spaces

In this paper, we generalize to sub-Riemannian Carnot groups some classical results in the theory of minimal submanifolds. Our main results are for step 2 Carnot groups. In this case, we will prove the convex hull property and some “exclosure theorems” for H-minimal hypersurfaces of class C2 satisfying a Hörmander-type condition.

Convex integration and the L p theory of elliptic equations

Kari Astala, Daniel Faraco, László Székelyhidi Jr. (2008)

Annali della Scuola Normale Superiore di Pisa - Classe di Scienze

This paper deals with the L p theory of linear elliptic partial differential equations with bounded measurable coefficients. We construct in two dimensions examples of weak and so-called very weak solutions, with critical integrability properties, both to isotropic equations and to equations in non-divergence form. These examples show that the general L p theory, developed in [1, 24] and [2], cannot be extended under any restriction on the essential range of the coefficients. Our constructions are based...

Cooperative driving at isolated intersections based on the optimal minimization of the maximum exit time

Jia Wu, Abdeljalil Abbas-Turki, Florent Perronnet (2013)

International Journal of Applied Mathematics and Computer Science

Traditional traffic control systems based on traffic light have achieved a great success in reducing the average delay of vehicles or in improving the traffic capacity. The main idea of these systems is based on the optimization of the cycle time, the phase sequence, and the phase duration. The right-of-ways are assigned to vehicles of one or several movements for a specific time. With the emergence of cooperative driving, an innovative traffic control concept, Autonomous Intersection Management...

Coplanar control of a satellite around the earth

Jean-Baptiste Caillau, Joseph Noailles (2001)

ESAIM: Control, Optimisation and Calculus of Variations

We investigate the minimum time transfer of a satellite around the Earth. Using an optimal control model, we study the controllability of the system and propose a geometrical analysis of the optimal command structure. Furthermore, in order to solve the problem numerically, a new parametric technique is introduced for which convergence properties are established.

Coplanar control of a satellite around the Earth

Jean-Baptiste Caillau, Joseph Noailles (2010)

ESAIM: Control, Optimisation and Calculus of Variations

We investigate the minimum time transfer of a satellite around the Earth. Using an optimal control model, we study the controllability of the system and propose a geometrical analysis of the optimal command structure. Furthermore, in order to solve the problem numerically, a new parametric technique is introduced for which convergence properties are established.

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