An operational tanker scheduling optimization system: model implementation, results and possible extensions

In a previous article by the same authors, we described the operational, short term tanker scheduling problem, focusing on the Chevron Shipping Company case study. We developed a model for the scheduling situation and described an integer programming formulation for schedule optimization. In this paper, we describe the scheduling system implementation on the University of Michigan IBM 3090-600E computer. The system generates feasible schedules for each vessel and then uses integer programming to attempt to solve for the optimal overall schedule. Use of the system and the potential for cost savings is demonstrated with a realistic scheduling situation based on Chevron Shipping Company information.