An overview of Lagrangian relaxation techniques to truck scheduling problems in cross-docking distribution centres

Cross-docking terminals are distribution centres where products coming from suppli- ers are unloaded from the inbound trucks, grouped into full-load truck shipments, and directly loaded into the outbound trucks, to be delivered to the customers. This zero- inventory distribution policy requires a high degree of synchronization between trucks, so as to avoid congestion inside the terminal and guarantee short lead times to cus- tomers. In this talk we deal with the truck scheduling problem. We will show how Lagrangian Relaxation techniques can be successfully applied to this class of problems, under different setting, and how from the mathematical properties of the relaxed prob- lem effective Lagrangian heuristic algorithms can be designed.