Ships’ response strategies to port disruptions caused by hurricanes

This paper studies ships' operational proactive strategies during the entire process of port disruptions due to environmental factors such as hurricanes. For the first time, the incompleteness and uncertainty of information, and the characteristics of port disruptions are considered. The problem is modeled as a nonhomogeneous Markov decision process (MDP), where different operational actions, such as sailing speed adjustment, handling rate adjustment, and port sequence adjustment are considered. The rolling horizon decision-making approach and a PSO-GA-based hybrid evolutionary algorithm are combined to solve the model. The results show that compared to the strategy without planned schedule adjustments, cost-saving up to 78.34% can be achieved by simultaneously adjusting the sailing speed, cargo handling rate, and port sequence. Counter-intuitively, we find that observing more complete hurricane information or having accurate forecasts does not always conducive to better decision-making. We also find the integration of multiple response strategies yields synergistic benefits. These findings will deepen our understanding of the impact of port disruptions and provide theoretical support for the decision-making of ship's response strategies.