The Performance Analysis of Priority Systems

This report summarizes the research conducted at The University of Texas at Austin on the performance analysis of priority systems for containers. The performance analysis focused on a selected group of possible priority systems that differ in the extent in which service by priority is implemented. The systems analyzed are: (a) base case, i.e., no service differentiation; (b) "hot hatch programs; (c) service differentiation at the storage yard; (d) service differentiation at the yard gate; and (e) combinations of systems (b), (c) and (d). The performance analysis was conducted using a simulation system specially designed to simulate priority systems. The performance of these systems is assessed for different combinations of the relevant experimental factors, namely: (a) operational scheme, (b) proportion of high priority containers, and (c) number of incoming containers. Using the resulting performance measures, the impacts on the different segments of users are assessed for each of the systems. Finally, the policy implications are analyzed and conclusions are drawn.