Mathematical Modelling and an Optimisation Approach to Container Terminal Yard Management Operations.

In container terminals, Yard Cranes (YCs) work at the interface between the storage yard and the internal and external trucks. A delay in the operations of the YCs will affect the overall operations of the container port. There is thus need for a good and reliable planning and scheduling of this resource for an effective day to day operation. Commonly, this is dealt with in an ad hoc way because of its complexity. A systematic approach for their planning and deployment is therefore required. The first focus of this thesis is on developing a mathematical model, the solution of which will minimise unfinished work in the yard at the end of a planning period by allocating and changing the YCs movements between yard blocks at different times. We propose two models for the Yard Crane Scheduling Problem (YCSP). In the first model, we introduced additional set of constraints to improve the performance of an existing model. The second model has the objective function of minimising the linear combination of unfinished work and surplus capacity. The problem is formulated as a mixed integer linear programming model, real world instances of which are solved in near-real time. This will help port managers to generate plans for YCs before the start of planning periods. Furthermore, this thesis examines the container reshuffle problem as a refinement of the scheduling problem. Once the YCs have been allocated to a bay, the reshuffle problem is defined and solved. So, the overall efficiency problem is solved in two stages, allocating YCs and scheduling each one of them using reshuffles to deal with the local load at the level of a bay. Four new heuristics referred to as the Least Priority Heuristic, LPH1, LPH2, LPH3 and LPH4 were developed to solve the reshuffle problem for a realistic size problem as they arise in the port for both static and dynamic cases. A compatibility test was proposed to test how well the different heuristics work when they are combined.