Robust scheduling of truck arrivals at a cross-docking platform

Abstract

This paper addresses an important planning operation which is the truck scheduling problem at a cross-docking terminal under full and partial information about the truck arrival times. The problem is subject to a resource-constrained crossdock; comprising the availability of the workforce and the handling equipment. One of the operational measures to control truck arrivals is the use of Appointment System (AS). AS is to establish coordination between cross-dock operator and truckers in order to determine when a truck can enter the cross-dock for loading or unloading operations. In spite of making appointment, the challenge is about the uncertainty factor of the earliness and the tardiness of truck arrivals and of the resource availability which implies the congestion at the platform. A fundamental issue about the congestion is the truck queueing behavior. To solve this issue, it is important to reduce the discipline of the queued trucks and to maintain the cost-efficiency of freight flows. One way of achieving this challenge is by applying the field of Queueing Theory (QT). In this paper, we focus on the question how to plan inbound truck arrivals effectively and what if trucks arrive outside the assigned time window. So, we present an efficient approach to optimize the allocation of arrival time of trucks and to optimize the resource schedules minimizing the total cost in the system. The proposed model is a mathematical formulation in conjunction with simulation that attempts to find a robust solution for cross-dock operator and trucks showing up late or early. Our early experimental results illustrate the working and benefit of our approach.