9. Pure Strategies Hiring cost = $100 per worker Firing cost = $500 per worker Regular production cost per pound = $2.00 Inventory carrying cost = $0.50 pound per quarter Production per employee = 1,000 pounds per quarter Beginning work force = 100 workers Example: QUARTER SALES FORECAST (LB) Spring 80,000 Summer 50,000 Fall 120,000 Winter 150,000
10. Level Production Strategy Level production = 100,000 pounds (50,000 + 120,000 + 150,000 + 80,000) 4 Spring 80,000 100,000 20,000 Summer 50,000 100,000 70,000 Fall 120,000 100,000 50,000 Winter 150,000 100,000 0 400,000 140,000 Cost of Level Production Strategy (400,000 X $2.00) + (140,00 X $.50) = $870,000 SALES PRODUCTION QUARTER FORECAST PLAN INVENTORY
11. Chase Demand Strategy Spring 80,000 80,000 80 0 20 Summer 50,000 50,000 50 0 30 Fall 120,000 120,000 120 70 0 Winter 150,000 150,000 150 30 0 100 50 SALES PRODUCTION WORKERS WORKERS WORKERS QUARTER FORECAST PLAN NEEDED HIRED FIRED Cost of Chase Demand Strategy (400,000 X $2.00) + (100 x $100) + (50 x $500) = $835,000
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14. LP MODEL Minimize Z = $100 ( H 1 + H 2 + H 3 + H 4 ) + $500 ( F 1 + F 2 + F 3 + F 4 ) + $0.50 ( I 1 + I 2 + I 3 + I 4 ) Subject to P 1 - I 1 = 80,000 (1) Demand I 1 + P 2 - I 2 = 50,000 (2) constraints I 2 + P 3 - I 3 = 120,000 (3) I 3 + P 4 - I 4 = 150,000 (4) Production 1000 W 1 = P 1 (5) constraints 1000 W 2 = P 2 (6) 1000 W 3 = P 3 (7) 1000 W 4 = P 4 (8) 100 + H 1 - F 1 = W 1 (9) Work force W 1 + H 2 - F 2 = W 2 (10) constraints W 2 + H 3 - F 3 = W 3 (11) W 3 + H 4 - F 4 = W 4 (12)
15. Transportation Method 1 900 1000 100 500 2 1500 1200 150 500 3 1600 1300 200 500 4 3000 1300 200 500 Regular production cost per unit $20 Overtime production cost per unit $25 Subcontracting cost per unit $28 Inventory holding cost per unit per period $3 Beginning inventory 300 units EXPECTED REGULAR OVERTIME SUBCONTRACT QUARTER DEMAND CAPACITY CAPACITY CAPACITY
17. Burruss’ Production Plan 1 900 1000 100 0 500 2 1500 1200 150 250 600 3 1600 1300 200 500 1000 4 3000 1300 200 500 0 Total 7000 4800 650 1250 2100 REGULAR SUB- ENDING PERIOD DEMAND PRODUCTION OVERTIME CONTRACT INVENTORY
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19. Hierarchical Nature of Planning Items Product lines or families Individual products Components Manufacturing operations Resource Level Plants Individual machines Critical work centers Production Planning Capacity Planning Resource requirements plan Rough-cut capacity plan Capacity requirements plan Input/ output control Aggregate production plan Master production schedule Material requirements plan Shop floor schedule All work centers
23. ATP: Example (cont.) ATP in April = (10+100) – 70 = 40 ATP in May = 100 – 110 = -10 ATP in June = 100 – 50 = 50 Take excess units from April = 30 = 0
24. Rule Based ATP Product Request Is the product available at this location? Is an alternative product available at an alternate location? Is an alternative product available at this location? Is this product available at a different location? Available-to-promise Allocate inventory Capable-to-promise date Is the customer willing to wait for the product? Available-to-promise Allocate inventory Revise master schedule Trigger production Lose sale Yes No Yes No Yes No Yes No Yes No
28. Yield Management: Example Hotel should be overbooked by two rooms NO-SHOWS PROBABILITY P ( N < X ) 0 .15 .00 1 .25 .15 2 .30 .40 3 .30 .70 Optimal probability of no-shows P( n < x ) = = .517 C u C u + C o 75 75 + 70 .517