Uniform stabilization of the quasi-linear Kirchhoff wave equation with a nonlinear boundary feedback

An n-dimensional quasi-linear wave equation defined on bounded domain Omega with Neumann boundary conditions imposed on the boundary Gamma and with a nonlinear boundary feedback acting on a portion of the boundary [Gamma sup 1 is a subset of Gamma] is considered. Global existence, uniqueness and uniform decay rates are established for the model, under the assumption that the H[sup 1](Omega) x L[sub 2](Omega) norms of the initial data are sufficiently small. The result presented in this paper extends these obtained recently in Lasiecka and Ong (1999), where the Dirichlet boundary conditions are imposed on the uncontrolled portion of the boundary Gamma[sub o] = Gamma \ [closure of a set Gamma sub 1], and the two portions of the boundary are assumed disjoint, i.e. [... ]. The goal of this paper is to remove this restriction. This is achieved by considering the "pure" Neumann problem subject to convexity assumption imposed on Gamma[sub o]. \@eng\