Journal of Operational Research and Its Applications ( Applied Mathematics ) - Lahijan Azad University

Transportation problems are usually considered in large-scale networks, where finding the optimal solution of these problems is so time-consuming and costly. Therefore, a useful method to solve the large-scale network problems is dividing them into some smaller sub-problems. In this paper, for the first time, the origin-destination (o-d) matrix estimation problem is considered through a mixed planar approach wherein the travel demands between o-d pairs are estimated in a large-scale network. A decomposition method is proposed in three phases. In each phase, the solution of some smaller problems in compared with the original one, are estimated. In the first phase, the travel demands between main nodes are estimated while in the second one, the flow pattern in all inner networks corresponding to main nodes is determined. In last phase, the travel demands between primary o-d pairs are estimated by using the obtained information from steps one and two.