Nonlinear self-adjointness of a generalized fifth-order KdV equation

Abstract

The new concepts of self-adjoint equations formulated by Ibragimov and Gandarias are applied to a class of fifth-order evolution equations. Then, from Ibragimov's theorem on conservation laws, conservation laws for the generalized Kawahara equation, simplified Kahawara equation and modified simplified Kawahara equation are established.