Ali Rahmani - PhD Student, University of California, USA

This paper takes as its basis an E-commerce distribution center with a fixed number of inbound and outbound bays. Inside the center operations are mainly processed via an automatic sorting system. As a result, workforce limitations can be ignored. All inbound trucks arrive at the distribution center yard at their scheduled time, and each outbound truck must wait until all orders are loaded but still has a suggested departure time. All cargos carried by inbound trucks have an appointed destination according to the E-commerce orders placed by customers. The required operation time for each inbound and outbound truck is also known in advance. In our model, there is a one-to-one correspondence between the recombination task j and the outbound truck.The complete operation process in the distribution center includes receiving, sorting, consolidating, and loading the recombined cargos for shipping. In our model we divide the whole process into two stages. The first stage refers to unloading cargos from inbound trucks and sending them to the sorting system. The second stage is recombining cargos according to customer orders and loading them on the specified outbound trucks for shipping. This division is based upon our recognition of the fact that the distribution center operation synchronization (DCOS) problem can be modelled as a two stage machine scheduling problem, about which there is already an abundant literature .

synchronization model, commerce logistics, operation