Obtain Algorithm

An origin-based solution algorithm, named OBTAIN (origin-based traffic assignment for infrastructure networks), was recently developed for solving the traffic assignment problems (Bar-Gera and Boyce, 2003). This algorithm defines the solution variables in an intermediate way between links and routes, and has been proven to be superior to the link-based Frank-Wolfe method in both computational time for and accurate level of the solution for a large network. To address its usefulness, the OBTAIN algorithm is elaborated in a tutorial manner, especially in its two major steps for updating the restricting subnetworks and origin-based approach proportions, and then applied to a small supply chain network equilibrium problem. The obtained results comply with the sufficient conditions for restricted user equilibrium. Future research includes a real application of large networks and a comparison of the OBTAIN algorithm with the route-based gradient projection (GP) algorithm in terms of computational efficiency.