New exact travelling wave solutions of two nonlinear physical models

In this paper, an improved tanh function method is used with a computerized symbolic computation for constructing new exact travelling wave solutions on two nonlinear physical models namely, the quantum Zakharov equations and the (2 + 1)-dimensional Broer-Kaup-Kupershmidt (BKK) system. The main idea of this method is to take full advantage of the Riccati equation which has more new solutions. The exact solutions are obtained which include new soliton-like solutions, trigonometric function solutions and rational solutions. The method is straightforward and concise, and its applications are promising. (c) 2006 Elsevier Ltd. All rights reserved.