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Strong convergence of selections implied by weak

Published online by Cambridge University Press:  17 April 2009

Tadeusz Rzezuchowski
Affiliation:
Institute of Mathematics, Warsaw Technical University, Pl.J.Robotniczej, 100-661 Warsaw, Poland
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Abstract

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In some situations weak convergence in L1, implies strong convergence. Let P, L: TC(ℝd) be measurable multifunctions (C(ℝd) being the set of closed, convex subsets of ℝd) the values L(t) affine sets and W(t) = P(t)L(t) extremal faces of P(t). Let pk be integrable selections of P, the projection of pk,(t) on L(t) and pk(t) on W(t). We prove that if converges weakly to zero then pkk converges to zero in measure. We give also some extensions of this theorem. As applications to differential inclusions we investigate convergence of derivatives of convergent sequences of solutions and we describe solutions which are in some sense isolated. Finally we discuss what can be said about control functions u when the corresponding trajectories of ẋ = f(t, x, u) are convergent to some trajectory.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1989

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