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,...

Problem Product Partition differs from the NP-complete problem Partition in that the addition operation is replaced by the multiplication operation. Furthermore it differs from the NP-complete problem Subset Product in that it does not contain the product value B in its input. We prove that...

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 Economic Order Quantity problem is a fundamental problem of inventory management. An optimal solution to this problem in a closed form exists under the assumption that time and the product are continuously divisible and demand occurs at a constant rate [lambda]. We prove that a discrete...