The value of information in stochastic-dynamic RoRo ship cargo handling

This paper addresses the planning of loading and unloading processes, also termed stevedoring, for Roll-on/Roll-off (RoRo) ships. We consider a setting where we sequence operations, assign tugs to handle trailers, and determine the cargo positions on the ship and in the yard. In real-world settings, the outcomes of these decisions are strongly affected by stochastic uncertainty, such as considering the type of cargo to unload or traffic congestion on the ship. To account for this, we formulate the problem as a sequential decision process and describe two feature-based policy function approximations for the decision-making. We propose an effective heuristic for designing policies in an offline learning process. We evaluate this approach in a case study at the Port of Kiel, Germany, simulating the service operations of a three-deck RoRo ship. Compared to industry benchmark policies, the proposed policies reduce the ship’s turnaround time by up to 26 min (8.8%). Additionally, we apply our methodology to illustrate the value of various levels of information availability. The results show that information on process completion times, especially for vehicle entry and exit at both the ship and the yard, has the potential to shave off turnaround time by an additional 8%. Yet, the availability of information on the incoming ship’s stowage plan is an important precondition for tailored policies capable of achieving such reductions, especially when there is a surplus of tug-handled cargo. • Real-world roll-on/roll-off ship terminal operations are affected by stochastic uncertainty. • We present a sequential decision process and feature-based policy function approximations for explainable decision-making. • Compared to benchmark policies, the proposed policies reduce the ship’s turnaround time by 8.8%. • Information on process completion times has the potential to reduce turnaround time by an additional 8%. • Information on the incoming ship’s stowage plan is an important precondition for achieving such reductions.