Coordinating Aggregate and Detailed Scheduling Decisions in the One-Machine Job Shop: Part I. Theory

This paper presents a formal model of the one-machine job-shop scheduling problem with variable capacity. Its primary interest focuses on the trade-off between overtime and detailed scheduling costs. The scheduling problem considered is minimizing the sum of weighted tardiness and weighted flow-time costs for a given capacity plan (i.e., a given overtime plan). The paper generalizes sequence-theory results to this case where possible, analyzes various lower-bounding structures for the problem, outlines a preliminary branch-and-bound algorithm, and illustrates several interesting features of the algorithm and bounding structures by an example. Extensions of the results to more complex environments are discussed.