A constraint programming based method for stockyard management problem

Abstract

The stockyard management problem in a cargo assembly terminal mainly focuses on finding an efficient allocation of limited resources such as stockyard space, stacking and reclaiming machines to stockpiles such that the waiting time of a vessel fleet at port can be minimized. This highly complex problem involves scheduling with resource constraints in a dynamic environment and is a typical NP-hard problem in general. In this study, we present a constraint programming (CP) based approach to address the problem with utilizing the strength of CP in its flexibility in formulating various complex and nonlinear constraints for industrial applications. In addition, we explore the ability of the CP solver with trying different combinations of constraint propagation and constructive search strategies and report our best findings from an extensive computational study.