Labour flexibility and assignment policies in a job shop having incommensurable objectives

This study evaluates operating policies for offering a near-perfect delivery performance for vital customers in dual resource-constrained (DRC) job shop environments. Prior studies have considered this problem in machine-limited settings, and shown that dispatching rules that help realise a near-perfect delivery performance for vital customers necessarily deteriorate delivery performance for other customers served by the shop. This study extends prior work, and considers additional tools that can be used by managers in DRC shops such as labour flexibility, and assignment rules that incorporate customer-based information to deploy workers to departments containing high-priority jobs. Results show that labour flexibility in conjunction with appropriate decision rules allows for enhanced delivery performance for both vital and normal priority customers. These results hold even under conditions where 80% of the shop's workload is composed of high-priority orders.