Exploring mathematical approximation for the time spans of transfer operations in parcel transshipment terminals

The parcel delivery industry (PDI) is a very labor intensive industry, from the drivers of the pickup and delivery vans, to the unloaders, sorters, and loaders in the transshipment terminals. The labor efficiency is a key performance measure in the PDI. In this study, the focus is on developing a framework for improving labor efficiencies in a parcel transshipment terminal. The objective is to minimize the time required to transfer parcels from inbound trailers to outbound trailers. This paper is an exploratory study to developing a framework for a solution approach to solve large‐scale parcel hub scheduling problems (PHSP). A binary integer programming (BIP) model is proposed along with a branch and bound (BaB) algorithm with lower and upper bounds. The computational study shows that the BaB algorithm is able to generate solutions for small‐size problems. The proposed BIP model sets the ground work for developing solution approaches to much larger size problems.