Peter A. Pinto

Branch and bound and heuristic procedures for assembly line balancing with paralleling of stations

Abstract A critical assumption made in formulating the classical assembly line balancing model is that the line is ‘serial’ with no ‘paralleling’ of stations allowed. A model is proposed here which allows the paralleling of stations, thereby achieving a higher production rate and lower labour costs. The mathematical formulation of the proposed model results in a mixed integer program. A branch and bound and a heuristic solution procedure, derived from the branch and bound method, are presented. An example problem is used for illustration. Some computational experience is also provided.

Joint lot-sizing and scheduling for multi-stage multi-product flow shops

Here we consider a multi-product flow shop under capacity constraints and develop an efficient heuristic procedure to determine joint lot sizes, production sequence and production schedule. We treat setup costs as fixed in the short run and thus independent of the number of setups. Loss of production capacity due to setup times is explicitly accounted for and the transfer of portions of a production lot between stages is permitted. The procedure is based on identifying the bottleneck workcentre and synchronizing production schedules at all other workcentres with the bottleneck workcentre such that product throughput requirements are met with minimal inventory costs. A compact procedure for constructing the Gantt charts is also presented. Conversion of the lot si2es and transfer batches into an information control system with kanbans is also presented.