CREATE THE DIFFERENCE Before you start Please press F5 to run this show.

CREATE THE DIFFERENCE Deterministic OR Techniques What follows is an example of the type of problem that needs solving using the techniques met in this module.

CREATE THE DIFFERENCE Production Scheduling - an example from the Confectionery Industry David Noble Principal Lecturer in Operational Research Faculty of Computing, Engineering and Technology Staffordshire University Stoke-on-Trent

CREATE THE DIFFERENCE Introduction This presentation describes a problem that the author was presented with by the Production Manager of a large confectionery manufacturer. Each Friday, the manager had to schedule production of 10 products for the following week. Two machines were available on which to make the products. Click on this link to see a diagram of the Production ProcessProduction Process Each product had to be demoulded on the same machine on which it was moulded.

CREATE THE DIFFERENCE Other Factors Some products could only be moulded (and therefore demoulded) on one of the two machines. Because each machine had to be cleaned and reset between products, only one product was moulded and one product demoulded each day on each machine (machine cleaning took place overnight). On each machine, demoulding of one product could be taking place at the same time as another was being moulded. One day’s production of one product filled one oven. A total of three ovens were available and any product could be put in any oven. Ovens were emptied and filled overnight. The amount of floor space was not a limiting factor.

CREATE THE DIFFERENCE Working Week The working week consisted of 5 days with the possibility of overtime at the weekend if necessary. Weekend working was necessary if labour was required to work the moulding/demoulding machines. Ovens were on automatic timers so could be set to switch off automatically over the weekend, requiring no labour. Product could remain in the ovens until the Monday. If this happened, their stay time (oven time + floor time) would be unaffected.

CREATE THE DIFFERENCE Products requested by the Sales Department for week 1

CREATE THE DIFFERENCE Products Already in Production

CREATE THE DIFFERENCE Planning horizon 2 week planning horizon Week 1 schedule adhered to - fixes which machine would demould which product in week 2 - some flexibility as to when demoulding would occur in week 2 16 day planning period (3 weekends) The problem was to schedule the production of the new products without using weekend working – if possible. If you want to see the mathematical formulation, click here.click here

CREATE THE DIFFERENCE Schedule produced for week 1

CREATE THE DIFFERENCE Altered schedule for week 1

CREATE THE DIFFERENCE The End Click here to go back to module informationhere