The problem of evaluating path marginal cost in system-optimal dynamic traffic assignment (SO-DTA) models was studied. A series of examples showed that path marginal costs are not simple additions of the corresponding link marginal costs unless the flow perturbation travels with the vehicle unit that initiated the perturbation. It is also shown that one can compute efficiently path marginal costs for networks with a special structure (i.e.mono-centric), and an evaluation method is proposed that decomposes path marginal costs to link marginal costs for such networks. The preliminary numerical experiments indicated that this solution scheme can generate numerical solutions close to analytical solutions where they are known. At present the method applies to networks without diverges and the embedded traffic flow models are restricted to those not considering queue spillback. The relaxation of either aspect brings additional challenges in predicting path flow perturbation propagation, hence additional difficulties in the evaluation of path marginal cost. For the covering abstract see ITRD E144727. Reprinted with permission of Elsevier.
Samenvatting