Simulation of Operational Policies for Transhipment in a Container Terminal LAWRENCE HENESEY, PAUL DAVIDSSON, JAN PERSSON Department of Systems and Software Engineering Blekinge Institute of Technology Biblioteksgatan 4, Karlshamn, 374 24 SWEDEN Abstract: - A simulation approach utilizing agent technology is applied to the problem of analysing operational policies for transhipping containers in a port container terminal. The managers involved in transhipment operations, i.e., the terminal manager, the port captain, the stevedores and the ship captains, as well as some of the operators of the physical resources, such as cranes and straddle carriers, are modelled as agents. To illustrate the approach, the simulator, called SimPort, has been configured based on real data from container terminals and used for comparing six transhipment policies in several scenarios. The policies concern the sequencing of ships and berth allocation. The policies are evaluated with respect to a number of aspects, such as, turn-around time for ships, and travelled distance of straddle carriers. Key-Words: - Container Terminals, Decision Support Systems, Multi Agent Based Simulation, Transhipment Operations, Berth Allocation, 1 Introduction The number of Twenty-foot Equivalent Unit containers (TEUs) shipped world-wide has increased from 39 million in 1980 to 356 million in 2004 and growth is still projected at an annual growth rate of 10% till 2020 [1]. Ports and container terminals (CTs) are trying to meet increasing demand by creating additional capacity. According to Drewry consultants, the cost for planning for container terminals in Northern Europe for 2004 is €549 million with total project costs reaching €6081 million [1, 2]. Many of the solutions considered can be classified as either physical expansion or increasing terminal performance. Some types of physical expansion solutions are purchase of new or additional equipment, hiring more labour, development and purchase of IT systems. Solutions that can be classified as increasing terminal performance are optimisation, use of simulation to use resources more efficiently. This paper presents a multi-agent based simulation (MABS) approach to evaluating different ways of increasing terminal performance. A simulator called SimPort has been developed to show the viability of this approach. The agent based approach offers the power of modeling the decision making processes of different actors. An application that may benefit in using an agent based approach is the operations of transhipping containers in a CT. The remainder of the paper is organized in the following way; first a general description of the CT transhipment processes is provided, then the agent- based simulator is presented. The design of the experiments is explained in section 4 which is followed by a description of the results that are analyzed and discussed. Finally, some conclusions are presented together with pointers to future work. 2 Container Terminal Description Container handling activities in CT are shown to be dependent on various related subsystems [3]. The managers involved are generally referred to as terminal managers, ship planners, yard planners, ship line agents, and resource planners. To satisfy the management goals for all the managers is difficult because they often have conflicting interests, i.e. the discharging of containers at a fast rate may lead to sub-optimal conditions for the stacking and positioning of containers in the yard. Ideally, the owners of arriving ships would like to ensure that when their ships arrive to a CT the berths are empty so there are no delays. On the other hand, CT management would like to reduce the capital outlay so that berths are always utilized. Sometimes one ship line can become dominant and its demands can take excessive importance, e.g. one ship requiring preferential service. The management of a CT can be a complex problem for CT managers to Proceedings of the 10th WSEAS International Conference on COMPUTERS, Vouliagmeni, Athens, Greece, July 13-15, 2006 (pp1289-1294)