Input Data (Demand) Input Data (Costs etc.)
Month Routers Switches Item Router Switch
January 1,800 1,600 Materials cost/unit
February 1,600 1,400 Inventory holding cost/unit/month 3.0 1.0
March 2,600 1,500 Marginal cost of stockout/unit/month
April 2,500 2,000 Hiring and training cost/worker
May 800 1,500 Layoff cost/worker
June 1,800 900 Labor hours required/unit 0.3333 0.1667
July 1,200 700 Regular time cost/hour 10.0
August 1,400 800 Over time cost/hour 15.0
September 2,500 1,400 Marginal subcontracting cost/unit
October 2,800 1,700
November 1,000 800 Initial Workforce size 6300
December 1,000 900 Maximum overtime per worker per month 20
Starting inventory (‘000s) 100 50
Ending inventory (‘000s) 100 50
Aggregate Plan Decision Variables (demand, inventory, production in ‘000s) Constraints
Ht Lt Wt Ot Router Switch Router Switch Router Router Switch Router Switch
Period # Hired # Laid off # Workforce Overtime Inventory Inventory Stockout Stockout Subcontract Production Production Demand Demand
Router
Inventory
Switch
Inventory
Overtime Production
0 0 0 6,300 0100 50 0 0
1 0 0 6,300 0.0 0.0 0.0 0 0 0 0 1,700 1,550 1,800 1,600 0 0 126000 183000.0
20 0 6,300 0.0 0.0 1448.0 0 0 0 0 1,600 2,848 1,600 1,400 0 0 126000 0.0
3 0 0 6,300 0.0 0.0 796.0 0 0 0 0 2,600 848 2,600 1,500 0 0 126000 0.0
40 0 6,300 26000.0 0.0 0.0 0 0 0 0 2,500 1,204 2,500 2,000 0 0 100000 0.0
5 0 0 6,300 0.0 0.0 0.0 0 0 0 0 800 1,500 800 1,500 0 0 126000 491333.3
60 0 6,300 0.0 0.0 0.0 0 0 0 0 1,800 900 1,800 900 0 0 126000 258000.0
7 0 0 6,300 0.0 0.0 0.0 0 0 0 0 1,200 700 1,200 700 0 0 126000 491333.3
80 0 6,300 0.0 0.0 1604.0 0 0 0 0 1,400 2,404 1,400 800 0 0 126000 140666.7
9 0 0 6,300 0.0 0.0 1252.0 0 0 0 0 2,500 1,048 2,500 1,400 0 0 126000 0.0
10 0 0 6,300 0.0 0.0 0.0 0 0 0 0 2,800 448 2,800 1,700 0 0 126000 0.0
11 0 0 6,300 0.0 0.0 0.0 0 0 0 0 1,000 800 1,000 800 0 0 126000 541333.3
12 0 0 6,300 0.0 100.0 50.0 0 0 0 0 1,100 950 1,000 900 0 0 126000 483000.0
Costs
Period Hiring Lay off Regular Time Overtime Inventory Stockout Subcontract
1 0 0 10,080,000 0 0 0 0
20 0 10,080,000 01,448,000 0 0
3 0 0 10,080,000 0796,000 0 0
40 0 10,080,000 390,000 0 0 0
5 0 0 10,080,000 0 0 0 0
60 0 10,080,000 0 0 0 0
7 0 0 10,080,000 0 0 0 0
80 0 10,080,000 01,604,000 0 0
9 0 0 10,080,000 01,252,000 0 0
10 0 0 10,080,000 0 0 0 0
11 0 0 10,080,000 0 0 0 0
12 0 0 10,080,000 0350,000 0 0
Total Cost =
126,800,000$
Switch
Subcontract