TY - EJOU AU - Wang, Xuechuan AU - Atluri, Satya N. TI - A Unification of the Concepts of the Variational Iteration, Adomian Decomposition and Picard Iteration Methods; and a Local Variational Iteration Method T2 - Computer Modeling in Engineering \& Sciences PY - 2016 VL - 111 IS - 6 SN - 1526-1506 AB - This paper compares the variational iteration method (VIM), the Adomian decomposition method (ADM) and the Picard iteration method (PIM) for solving a system of first order nonlinear ordinary differential equations (ODEs). A unification of the concepts underlying these three methods is attempted by considering a very general iterative algorithm for VIM. It is found that all the three methods can be regarded as special cases of using a very general matrix of Lagrange multipliers in the iterative algorithm of VIM. The global variational iteration method is briefly reviewed, and further recast into a Local VIM, which is much more convenient and capable of predicting long term complex dynamic responses of nonlinear systems even if they are chaotic. KW - Variational iteration method KW - Adomian decomposition method KW - Picard iteration method KW - asymptotic technique KW - nonlinear dynamical system DO - 10.3970/cmes.2016.111.567