Designing robust liner shipping schedules: Optimizing recovery actions and buffer times

Maritime transport is an important mode of transport in international trade. It is important for liner shipping companies to maintain cost efficient and robust liner shipping networks. Regularly, they set up pro-forma schedules, yet it is difficult to stay on time and we consider the problem to manage the delays. Therefore, we need to determine an optimal recovery policy and buffer time distribution of the ship route in order to minimize the total costs associated to delays and recovery actions, such as increasing sailing speed. We will introduce a mixed integer programming formulation and two heuristical methods to solve this problem. We found a cost decrease of 14.8% after optimizing the buffer time distribution based on an existing liner shipping route compared to the cost of the current route schedule.