Note: For these problems, to simplify data handling to include the receipt of orders that have actually been placed in previous periods, the following six-level scheme can be used. (A number of different techniques are used in practice, but the important issue is to keep track of what is on hand, what is expected to arrive, what is needed, and what size orders should be placed.) One way to calculate the numbers is as follows:
One unit of A is composed of two units of B and three units of C. Each B is composed of one unit of F. C is made of one unit of D, one unit of E, and two units of F. Items A, B, C, and D have 20, 50, 60, and 25 units of on-hand inventory, respectively. Items A, B, and C use lot-for-lot (L4L) as their lot-sizing technique, while D, E, and F require multiples of 50, 100, and 100, respectively, to be purchased. B has scheduled receipts of 30 units in Period 1. No other scheduled receipts exist. Lead times are one period for Items A, B, and D, and two periods for Items C, E, and F. Gross requirements for A are 20 units in Period 1, 20 units in Period 2, 60 units in Period 6, and 50 units in Period 8. Find the planned order releases for all items.