A GRASP for Supply Chain Optimization with Financial Constraints per Production Unit

Abstract

This paper deals with supply chain optimization using the job-shop model where extra flow constraints are included modelizing cash flow exchanges between different supply chain partners including suppliers, retailers and manufacturers. The problem under study called job-shop with financial constraint is defined as a job-shop problem with simultaneous consideration of machine specific resource requirements and financial constraints. Tackling financial considerations permits to consider a proper coordination of production units when optimizing the supply chain planning and cash flows. The main goal is to obtain the smallest duration of a given supply chain operational planning that respects the budget limit of each production unit. We use a disjunctive graph formulation to model both the job-shop problem and cash flow constraints. We also propose a powerful and efficient GRASPxELS procedure as a solution method. The developed approach for supply chain modeling is novel in the sense that the model encompasses specific financial resource per machine i.e. per plant. The method efficiency is evaluated on a set of instances coming from the Laurence’s job-shop instances.