Asymptotic analysis for the strip problem related to a parabolic third - order operator

Aim of this paper is the qualitative analysis of a boundary value problem for a third order non linear parabolic equation which describes several dissipative models. When the source term is linear, the problem is explictly solved by means of a Fourier series with properties of rapid convergence. In the non linear case, appropriate estimates of this series allow to deduce the asymptotic behaviour of the solution.