A Prototype Problem We will illustrate the various techniques for solving aggregate planning problems with the following example Densepack is to plan workforce and production levels for the six-month period January to June. The firm produces a line of disk drives for mainframe computers that are plug compatible with several computers produced by major manufacturers. Forecast demands over the next six months for a particular line of drives produced in the Milpitas, California, plant are 1,280, 640, 900, 1,200, 2,000, and 1,400. There are currently end of December) 300 workers employed in the Milpitas plant. Ending inventory in December is expected to be 500 units, and the firm would like to have 600 units on hand at the end of June. There are several ways to incorporate the starting and the ending inventory constraints into the formulation. The most convenient is simply to modify the values of the predicted demand Deline net predicted demand in period 1 as the predicted demand minus initial inventory. If there is a minimum ending inventory constraint, then this amount should be added to the demand in period T. Minimum buffer inventories also can be handled by modifying the predicted demand If there is a minimum buffer inventory in every period, this amount should be added to the first period's demand. If there is a minimum buffer inventory in only one period, this amount should be added to that period's demand and subtracted from the next period's demand. Actual ending inventories should be computed using the original demand pattern, however