Displaying 881 – 900 of 2827

Showing per page

Extremal selections of multifunctions generating a continuous flow

Alberto Bressan, Graziano Crasta (1994)

Annales Polonici Mathematici

Let F : [ 0 , T ] × n 2 n be a continuous multifunction with compact, not necessarily convex values. In this paper, we prove that, if F satisfies the following Lipschitz Selection Property: (LSP) For every t,x, every y ∈ c̅o̅F(t,x) and ε > 0, there exists a Lipschitz selection ϕ of c̅o̅F, defined on a neighborhood of (t,x), with |ϕ(t,x)-y| < ε, then there exists a measurable selection f of ext F such that, for every x₀, the Cauchy problem ẋ(t) = f(t,x(t)), x(0) = x₀, has a unique Carathéodory solution, depending...

Extremal solutions and relaxation for second order vector differential inclusions

Evgenios P. Avgerinos, Nikolaos S. Papageorgiou (1998)

Archivum Mathematicum

In this paper we consider periodic and Dirichlet problems for second order vector differential inclusions. First we show the existence of extremal solutions of the periodic problem (i.e. solutions moving through the extreme points of the multifunction). Then for the Dirichlet problem we show that the extremal solutions are dense in the C 1 ( T , R N ) -norm in the set of solutions of the “convex” problem (relaxation theorem).

Factorisation d'opérateurs différentiels à coefficients dans une extension liouvillienne d'un corps valué

Magali Bouffet (2002)

Annales de l’institut Fourier

On démontre ici un lemme de Hensel pour les opérateurs différentiels. On en déduit un théorème de factorisation pour des opérateurs différentiels à coefficients dans une extension liouvillienne transcendante d’un corps valué. On obtient en particulier un théorème de factorisation pour des opérateurs différentiels à coefficients dans une extension de ( ( z ) ) par un nombre fini d’exponentielles et de logarithmes algébriquement indépendants sur ( ( z ) ) .

Filippov Lemma for certain second order differential inclusions

Grzegorz Bartuzel, Andrzej Fryszkowski (2012)

Open Mathematics

In the paper we give an analogue of the Filippov Lemma for the second order differential inclusions with the initial conditions y(0) = 0, y′(0) = 0, where the matrix A ∈ ℝd×d and multifunction is Lipschitz continuous in y with a t-independent constant l. The main result is the following: Assume that F is measurable in t and integrably bounded. Let y 0 ∈ W 2,1 be an arbitrary function fulfilling the above initial conditions and such that where p 0 ∈ L 1[0, 1]. Then there exists a solution y ∈ W 2,1...

Filippov Lemma for matrix fourth order differential inclusions

Grzegorz Bartuzel, Andrzej Fryszkowski (2014)

Banach Center Publications

In the paper we give an analogue of the Filippov Lemma for the fourth order differential inclusions y = y”” - (A² + B²)y” + A²B²y ∈ F(t,y), (*) with the initial conditions y(0) = y’(0) = y”(0) = y”’(0) = 0, (**) where the matrices A , B d × d are commutative and the multifunction F : [ 0 , 1 ] × d c l ( d ) is Lipschitz continuous in y with a t-independent constant l < ||A||²||B||². Main theorem. Assume that F : [ 0 , 1 ] × d c l ( d ) i s m e a s u r a b l e i n t a n d i n t e g r a b l y b o u n d e d . L e t y₀ ∈ W4,1 b e a n a r b i t r a r y f u n c t i o n s a t i s f y i n g ( * * ) a n d s u c h t h a t ...

Currently displaying 881 – 900 of 2827