URBAN ROAD NETWORK MODELING PROBLEM : FORMULATION AND ALGORITHMS

Planners of urban traffic or transportation systems treat with their own network models of urban road Abstract networks constructed based on their objectives. Usually, those models seem to be determined empirically, and it may not be clear if the planners' objectives are reflected on them or not. This paper presents (i) a formulation of a network modeling problem for urban road networks as a combinatorial optimization problem, (ii) its solution algorithm based on implicit enumeration, (iii) its extensions for some restricted conditions, (iv) some suboptimal techniques for large-scale networks, and (v) some practical examples from vehicle traffic network planning of Tokyo and Nagoya city areas. By the presented algorithm, the planners can obtain network models of appropriate size which are "optimal" in the sense that they reflect best the planners' objectives. From the results of examples, it is verified that the presented algorithm, its extensions and suboptimal techniques provide an effective procedure for network modeling problems, which is applicable for practical use.