Transfer Synchronization of Public-Transport Networks

Transfers in public transport, especially in bus operations, are used to create a more efficient network by the reduction of operational costs and the allowance of more flexible route planning. However, because of the stochastic nature of traffic, scheduled transfers do not always occur; this situation increases the total passenger travel time and reduces the attractiveness of the public transport service. The use of selected operational tactics in public transport networks for increasing the actual occurrence of scheduled transfers was analyzed. A model was developed to determine the impact that instructing vehicles to either hold at or skip certain stops had on total passenger travel time and the number of simultaneous transfers. The model consisted of two components. First, a simulation of a public transport network examined the two tactics for maximizing the number of transfers. Second, an ILOG optimization model was used for optimal determination of the combination of the two tactics to achieve the maximum number of simultaneous transfers. A bus network was created as a case study, in Auckland, New Zealand, to verify the impact of the model's application. Results showed that applying online operational tactics dramatically improved the frequency of simultaneous transfers by more than 100%. The concept has great potential for increasing the efficiency and attractiveness of public transport networks that involve scheduled transfers.