Subnetwork origin-destination matrix estimation considering network topology

To design and evaluate the local transportation road network, the subnetwork origin-destination (OD) demand is estimated using the method of topology analysis. The nodes on the boundary of the subnetwork and inside the subnetwork are analyzed based on the subnetwork topology structure. The nodes on the boundary of the subnetwork, which connect with the outside of the subnetwork, generate or attract traffic flows; and the demands of the nodes inside the subnetwork are the same as those in the original full network. Then, the subnetwork OD matrix estimation model considering the subnetwork topology is established. This new model considers the maximum entropy and elasticity of OD demands in the objective function, and uses the OD demands as the constraints. The original problem is divided into solving the OD demand and road impedance, respectively. The heuristic iterative algorithm is designed to solve the established model, and the convex combination algorithm is developed to calculate the OD demand. The Sioux Falls network is used to illustrate the essential idea of the proposed model and the applicability of the proposed solution algorithm. The results show that the proposed model with elastic demand is superior to the OD estimation model with fixed demand in the terms of reliability and computational accuracy. The designed algorithm can rapidly convergence to the required accuracy, and the proposed model is an effective approach for simplifying the full network. © 2017, Editorial Department of Journal of Southeast University. All right reserved.