Integration of scheduling and routing for two-echelon supply chain system

Coordinating activities among supply, production, and delivery is an important issue for production and logistics management. In this study, a single machine scheduling model is developed that incorporated order release and delivery vehicle routing decisions which serves a single customer location. The objective is to minimize the makespan. The problem is NP-hard in the strong sense in general. Two integer programming models are developed to optimally solve this problem. Also, two efficient heuristics are proposed for solving large-sized problems. Computational results of the illustrative example are reported using the two integer programming models and two heuristics to solve the proposed problem.