Transcript Class-6a
Operations Management & Performance Modeling 1 Operations Strategy 2 Process Analysis 3 Lean Operations 4 Supply Chain Management – Class 5a: Inventories & Economies of Scale – Class 5b: Dealing with Uncertainty & role of Centralization – Class 6a: Supply Chain Design » Multi-product Pooling: Postponement & Commonalities » Benetton » Accurate Response 5 Capacity Management in Services 6 Total Quality Management 7 Business Process Reengineering OM&PM/Class 6a 1 Postponement & Commonality: HP Laserjet Generic Power Production Unique Power Production Transportation Europe Process I: Unique Power Supply N. America Europe Process II: Universal Power Supply Make-to-Stock OM&PM/Class 6a N. America Push-Pull Boundary Make-to-Order 2 HP LaserJet: European DC Safety Stocks (2 month Lead time) European Options A Monthly Mean 42.3 Monthly SD Safety Stock 32.4 92 AA 420.2 203.9 577 AB 15830.1 5624.6 15909 AQ 2301.2 1168.5 3305 AU 4208.0 2204.6 6236 AY 306.8 103.1 292 OM&PM/Class 6a 3 HP LaserJet: The Effect of Aggregation Total European safety stock with 2 month lead time = 26,409 units. Total European safety stock with 2 month lead time on aggregation = 17,661 units. Reduction OM&PM/Class 6a = 8,749 units (33%). 4 United Colors of Benetton Production Process OM&PM/Class 6a 6 Benetton Extra Cost of Postponement factory shipments woolen items – $311M x 60% = $186.6M Labor and O/H costs woolen items – 6.6% + 21.8% (assuming half of O/H from Exh. 1) = 28.4% – $186.6M x 28.4% = $53.0M If 10% of items are dyed to order at 10% extra cost – $53.0M x 10% x 10% = $0.53M OM&PM/Class 6a 7 Benetton Inventory Benefits of its Strategy Benetton Sales $305,000 Margins 37% COGS $192,150 Avg. Store Inv. $40,000 Inv. Turns 4.80 Cost of Woolen Items $186.6m Avg. Inv. $38.875m European Store $150,000 45% $82,500 $30,000 2.75 $186.6m $67.9m Inv. Turns = Avg. Throughput (COGS)/Avg. Inventory Inventory Reduction = ($67.9-$38.875)M = $29.025M Savings in inventory carrying costs (@25%) = $7.256M OM&PM/Class 6a 8 Benetton Profitability of Agents Commissions (FY 81) (4% on shipments) – $311M * 4% / 70 agents = $178K / agent Earnings on Shop Sales (10% ownership) – Sales = $311M * 180% (markup) * 37/44 (realized markup) = $471M – NIBT = $471M*19% = $89M – 10% ownership = $8.9M/70 agents = $128K / agent Total = $306K / agent OM&PM/Class 6a 9 Benetton Profitability of Retailers/Franchisees (FY 81) Store Sales = $305K NIBT = 19% * $305K = $58K Less agent’s share ($5.8K) = $52K OM&PM/Class 6a 10 Postponement and Re-assortment: The Advantage to Forecasting Actual total sales 4000 4000 4000 3500 3500 3500 3000 3000 3000 2500 2500 2500 2000 2000 2000 1500 1500 1500 1000 1000 1000 500 500 500 0 0 0 0 500 1000 1500 2000 2500 3000 3500 4000 Initial Forecast 0 500 1000 1500 2000 2500 3000 3500 4000 0 Updated Forecast after observing 20% of sales 500 1000 1500 2000 2500 3000 3500 4000 after 80% Each data point represents the forecast and the actual season sales for a particular item (at the style-color level). OM&PM/Class 6a 11 Take-Away’s: Benetton is an example of how to manage an entire supply chain and make it profitable for all entities in the chain (suppliers, Benetton, agents, retailers) by tailoring its operational response very carefully: – Step 1. Reduce S, L, variability: » the basics: implement everywhere in supply chain: highest pay-back – Step 2. Centralization » intermediate: trick is in the implementation: medium pay-back – Step 3. Partial postponement flexibility » last step: need this on only a small set of products & processes and OM&PM/Class 6a meshing it with financial and marketing response. 12 Accurate Response to Demand Uncertainty when you can order only once: L.L. Bean L.L. Bean is planning the order size for winter parkas. Each parka costs the company $70 and sells for $140. Any unsold parkas at the end of the season are disposed off by a sale at $40. Using historical data and a feel for the market, L.L. Bean forecasts the winter season demand: Demand: 21 Probability: 3% 22 4% 23 5% 24 8% 25 10% 26 15% 27 12% 28 10% Demand: Probability: 29 9% 30 6% 31 5% 32 4% 33 4% 34 3% 35 2% How many parkas should L.L. Bean plan (make/order)? OM&PM/Class 6a 13 Accurate Response: Find optimal order level Q with Excel Order size Q 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 Purchase price = Retail Price = Sale price = OM&PM/Class 6a Probability Demand = Q 0.03 0.04 0.05 0.08 0.10 0.15 0.12 0.10 0.09 0.06 0.05 0.04 0.04 0.03 0.02 Cumulative P (Demand < Q ) 0.03 0.07 0.12 0.20 0.30 0.45 0.57 0.67 0.76 0.82 0.87 0.91 0.95 0.98 1.00 $ $ $ Expected Payoff 1470.0 1537.0 1600.0 1658.0 1708.0 1748.0 1773.0 1786.0 1789.0 1783.0 1771.0 1754.0 1733.0 1708.0 1680.0 70.00 140.00 40.00 14 Accurate response: Find optimal Q from formula Cost of overstocking by one unit = Co – the out-of-pocket cost per unit stocked but not demanded – “Say demand is one unit below my stock level. How much did the one unit overstocking cost me?” E.g.: purchase price - salvage price. Cost of understocking by one unit = Cu – The opportunity cost per unit demanded in excess of the stock level provided – “Say demand is one unit above my stock level. How much could I have saved (or gained) if I had stocked one unit more?” E.g.: retail price - purchase price. Given an order quantity Q, increase it by one unit if and only if the expected benefit of being able to sell it exceeds the expected cost of having that unit left over. At optimal Q, do not order more if Prob( Demand > Q ) < Co /(Co + Cu ). OM&PM/Class 6a 15 Wal-Mart – Provide customers access to quality good, when and where needed at competitive prices Operations strategy – Short cycle times – Low inventory levels Logistics structure Strategic goals Logistics strategy – Accurate information availability – Rapid transportation OM&PM/Class 6a – – – – – – Electronic data interchange Communication between retail stores Bar coding Cross docking Fast responsive transportation system Long lead time items » Stored at DC and shipped as needed – Stable demand items » Continuous replenishment programs – Short lead time items » Made to order and cross-docked at DC 16 Class 6a: Learning Objectives Pooling of stock reduces the amount of inventory – physical – information Single product – specialization – substitution – commonality/postponement Multi product Benetton: Tailored response (e.g., partial postponement) can be used to better match supply and demand Accurate Response in one-shot inventory management under uncertainty – trade-off cost of over and understocking OM&PM/Class 6a 17