Real-time schedule recovery in liner shipping service with regular uncertainties and disruption events

- We study how a vessel can adjust its speed to handle uncertainties.
- We differentiate regular uncertainties and unexpected disruptions in modeling.
- We formally formulate the problem by a stochastic optimal control model.
- We analytically derive a number of properties of the optimal policies.
- We conduct extensive computational studies to validate our model and analysis.

This paper studies real-time schedule recovery policies for liner shipping under various regular uncertainties and the emerging disruption event that may delay a vessel from its planned schedule. The aim is to recover the affected schedule in the most efficient way. One important contribution of this work is to explicitly distinguish two types of uncertainties in liner shipping, and propose different strategies to handle them. The problem can be formulated as a multi-stage stochastic control problem that minimizes the total expected fuel cost and delay penalty. For regular uncertainties that can be characterized by appropriate probabilistic models, we develop the properties of the optimal control policy; then we show how an emerging disruption may change the control policies. Numerical studies demonstrate the advantages of real-time schedule recovery policies against some typical alternatives.