Singlebatch lot streaming in a twostage assembly system

We address a single–batch lot streaming problem for a two–stage assembly system. The first stage consists of m parallel subassembly machines, each devoted to a component type. A single assembly machine at the second stage assembles a unit of a product after all m components (one each from the subassembly machines) are ready. The batch consists of U units. Detached or attached setups are necessary before the start of the first item on each machine. Given a fixed maximal number of sublots, the problem is to determine integer sublot sizes to minimise the makespan. We present a polynomial–time algorithm to obtain an optimal solution.