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Uniqueness results for the Minkowski problem extended to hedgehogs

Yves Martinez-Maure (2012)

Open Mathematics

The classical Minkowski problem has a natural extension to hedgehogs, that is to Minkowski differences of closed convex hypersurfaces. This extended Minkowski problem is much more difficult since it essentially boils down to the question of solutions of certain Monge-Ampère equations of mixed type on the unit sphere 𝕊 n of ℝn+1. In this paper, we mainly consider the uniqueness question and give first results.

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Н.Х. Ибрагимов, Е.В. Мамонтов (1977)

Matematiceskij sbornik

Upper and Lower Solutions Method for Darboux Problem for Fractional Order Implicit Impulsive Partial Hyperbolic Differential Equations

Saïd Abbas, Mouffak Benchohra (2012)

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

In this paper we investigate the existence of solutions for the initial value problems (IVP for short), for a class of implicit impulsive hyperbolic differential equations by using the lower and upper solutions method combined with Schauder’s fixed point theorem.

Upper bounds for a class of energies containing a non-local term

Arkady Poliakovsky (2010)

ESAIM: Control, Optimisation and Calculus of Variations

In this paper we construct upper bounds for families of functionals of the form E ε ( φ ) : = Ω ε | φ | 2 + 1 ε W ( φ ) d x + 1 ε N | H ¯ F ( φ ) | 2 d x where Δ H ¯ u = div { χ Ω u}. Particular cases of such functionals arise in Micromagnetics. We also use our technique to construct upper bounds for functionals that appear in a variational formulation of the method of vanishing viscosity for conservation laws.

Variational Framework for Assessment of the Left Ventricle Motion

J. Garcia-Barnés, D. Gil, S. Pujadas, F. Carreras (2008)

Mathematical Modelling of Natural Phenomena

Impairment of left ventricular contractility due to cardiovascular diseases is reflected in left ventricle (LV) motion patterns. An abnormal change of torsion or long axis shortening LV values can help with the diagnosis and follow-up of LV dysfunction. Tagged Magnetic Resonance (TMR) is a widely spread medical imaging modality that allows estimation of the myocardial tissue local deformation. In this work, we introduce a novel variational framework for extracting the left ventricle dynamics from...

Variational-hemivariational inequalities in nonlinear elasticity. The coercive case

Panagiotis D. Panagiotopoulos (1988)

Aplikace matematiky

Existence of a solution of the problem of nonlinear elasticity with non-classical boundary conditions, when the relationship between the corresponding dual quantities is given in terms of a nonmonotone and generally multivalued relation. The mathematical formulation leads to a problem of non-smooth and nonconvex optimization, and in its weak form to hemivariational inequalities and to the determination of the so called substationary points of the given potential.

Wasserstein gradient flows from large deviations of many-particle limits

Manh Hong Duong, Vaios Laschos, Michiel Renger (2013)

ESAIM: Control, Optimisation and Calculus of Variations

We study the Fokker–Planck equation as the many-particle limit of a stochastic particle system on one hand and as a Wasserstein gradient flow on the other. We write the path-space rate functional, which characterises the large deviations from the expected trajectories, in such a way that the free energy appears explicitly. Next we use this formulation via the contraction principle to prove that the discrete time rate functional is asymptotically equivalent in the Gamma-convergence sense to the functional...

Wave front set for positive operators and for positive elements in non-commutative convolution algebras

Joachim Toft (2007)

Studia Mathematica

Let WF⁎ be the wave front set with respect to C , quasi analyticity or analyticity, and let K be the kernel of a positive operator from C to ’. We prove that if ξ ≠ 0 and (x,x,ξ,-ξ) ∉ WF⁎(K), then (x,y,ξ,-η) ∉ WF⁎(K) and (y,x,η,-ξ) ∉ WF⁎(K) for any y,η. We apply this property to positive elements with respect to the weighted convolution u B φ ( x ) = u ( x - y ) φ ( y ) B ( x , y ) d y , where B C is appropriate, and prove that if ( u B φ , φ ) 0 for every φ C and (0,ξ) ∉ WF⁎(u), then (x,ξ) ∉ WF⁎(u) for any x.

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