simulation of operating procedures and infrastructure changes in the upper mississippi navigation system
We use discrete-event simulation to investigate the effects of proposed operational policies and infrastructure changes for a series of locks that create a seasonal bottleneck for commercial barge operations. Traffic scheduling rules derived from a nonlinear integer programming model are tested over highly time-varying traffic mixes and traffic intensities in the shipping season. With the simulation model, we show the impact of alternative priority shifting rules and identify traffic levels at which major infrastructural improvements are required. We identify self-regulating behavior of the system when it is under stress and see how stochastic phenomena mute the benefits of scheduling strategies inferred from deterministic optimizing models. Finally, we compare the benefits derived from infrastructure investments with highly different capital costs. The results are relevant to other transportation or service systems involving series of separated servers with bi-directional traffic flows, several classes of user or customer, random itineraries, and random transit time between servers.
optimal scheduling inland waterway operations des transportation infrastructure