Batch scheduling in customer-centric supply chains

Supply chain scheduling is a new emerging area of research. We study batch arrival scheduling problems at the manufacturer in a multi-level customer-centric supply chain, where promised job due dates are considered constraints which must be satisfied. We analyze the tradeoff between inventory holding costs and batch delivery costs. We show that the problems are closely related to batch scheduling problems on a single machine with flow-time related objectives. We prove that minimizing the sum of total weighted flow time and delivery costs is strongly NP-hard. For the unweighted version of the problem, we present efficient solution algorithms both for single machine and assembly systems. We also develop a dynamic programming solution for minimizing the sum of maximum flow time and delivery costs.