eng Science and Education Publishing American Journal of Numerical Analysis 2372-2126 2016-04-14 4 1 8 10 10.12691/ajna-4-1-2 AJNA2016412 article Arash Ghahraman arash.ghgood@gmail.com 1 Department of Physics, Faculty of Basic Science, Chabahar Maritime University, Chabahar, Iran This paper studies nonlinear waves in the presence of weak external perturbation. Dynamical behavior of kink is examined. Adomian decomposition method is employed to study the kink-impurity interaction. As a result, an analytical approximate solution is derived. Then some of the first terms of the series solution are considered to show the kink behavior in the presence of impurity. http://pubs.sciepub.com/ajna/4/1/2/ajna-4-1-2.pdf Soliton phi4 Kinks Delta function Adomian Decomposition method