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This paper focuses on how to optimally route transfer cranes in a container yard during loading operations of export containers at port terminals. Decision variables are the number of containers that a transfer crane picks up at each yard-bay and the sequence of yard-bays that a transfer crane visits during a loading operation. This routing problem is formulated as a mixed integer program. The objective function of the formulation is to minimize the total container handling time of a transfer crane, which includes setup time at each yard-bay and travel time between yard-bays. Based on the mixed integer program, an optimizing algorithm is developed.

To reduce delay in ship operations in automated container terminals, it is important to make different types of container handling equipment to operate harmoniously during this operation. Delivery operations by automated guided vehicles (AGVs) play an important role for synchronizing operations of container cranes with yard cranes. This study discusses how to dispatch AGVs by utilizing information about locations and times of future delivery tasks. A mixed-integer programming model is provided for assigning optimal delivery tasks to AGVs. A heuristic algorithm is suggested for overcoming the excessive computational time needed for solving the mathematical model. Objective values and computational times of the heuristic algorithm are compared with those of the optimizing method. To test performances of the heuristic algorithm, a simulation study is performed by considering the uncertainties of various operation times and the number of future delivery tasks for looking ahead. Also, the performance of the heuristic algorithm is compared with those of other dispatching rules.