Scheduling of discrete event transport systems

Computing a schedule for discrete transport system is a crucial way of determining operations and operations-related figures, for transport systems. This can relate for instance, to decide which containers should be unloaded from a ship , which train should go first, whether a train should wait for a delayed container, or whether entire transport systems would work as planned.

For instance, the Inter Terminal Transport problem is being analyzed within the project “Inter-terminal transport on Maasvlakte 1 and 2 in 2030 - Towards a multidisciplinary and innovative approach on future inter-terminal transport options”. The goal of the project is to develop innovative, non-conventional concepts for the transport of containers within the terminals at the Maasvlakte area, at the port of Rotterdam.

In fact, a dedicated Inter Terminal Transport (ITT) system must be able to efficiently transport containers inside the port area over a separate road preventing congestion on the ports entry roads, bundling incoming and outgoing container demand, and increasing competitiveness of the port.

The main question to be answered is:  how many vehicles would be necessary to achieve a given performance? Where by far the most important performance indicators relate to hoe many containers are delivered in time and how much too late they have been delivered. This  is quite relevant for the planning of the all area by Port of Rotterdam Authority. The answer is found by means of a combinatorial problem, namely a deterministic minimum cost flow model with time expanded graphs.

The current findings include the importance of speed of vehicles: when vehicles with conventional speeds are used the required number of vehicles is significantly increased, up to a point that congestion might become an issue.

This research is supported by the Port Research Center project “Innovative Concepts for Inter Terminal Transport on Maasvlakte 1 and 2 at the Port of Rotterdam”.

For more information please contact Dr Rudy Negenborn; Dr. Francesco Corman, Ir. Mark Duinkerken