We consider the problem of scheduling multi-operation jobs on a singe machine to minimize the total completion time. Each job consists of several operations that belong to different families. In a schedule each family of job operations may be processed as batches with each batch incurring a...

The single-item capacitated economic lot-sizing (CELS) problem is a fundamental problem of production and inventory management. The first fully polynomial approximation scheme (FPTAS) for this problem with concave cost functions was developed by Van Hoesel and Wagelmans [C.P.M. Van Hoesel,...