Matching Supply with Demand: An Introduction to Operations Management Gérard Cachon ChristianTerwiesch All slides in this file are copyrighted by Gerard Cachon and Christian Terwiesch. Any instructor that adopts Matching Supply with Demand: An Introduction to Operations Management as a required text for their course is free to use and modify these slides as desired. All others must obtain explicit written permission from the authors to use these slides.

Figure 2.1: Example of a procedure in an interventional radiology unit

Ideal Scenario for a patient (first patient, no waiting times) Figure 2.2: Gantt chart summarizing the activities for interventional radiology 7:458:008:158:308:459:009:159:30 9:45 10:00 Registration Initial consultation Preparation of room Preparation of patient Procedure Remove equipment Recovery Consultation Activity taking place in angiography suite Time

12:3012:4513:0013:1513:3013:4514:0014:1514:3014:45 15:00 Figure 2.3: Gantt chart summarizing the activities for a patient arriving at 12:30 Registration Initial consultation Preparation of room Preparation of patient Procedure Remove equipment Recovery Consultation Patient waits Activity taking place in angiography suite Time

7:008:009:0010:0011:0012:0013:0014:0015:0016:0017:00 18:00 Figure 2.4: Time patient spent in the interventional radiology unit (for patients treated in main room only), including room preparation time Patient wait Room prepared before patient arrives Patient 9 Patient 8 Patient 6 Patient 5 Patient 4 Patient 1 Activity taking place in angiography suite Time

7:008:009:0010:0011:0012:0013:0014:0015:0016:0017:0018:00 Figure 2.5.: Usage of the main room Patient 1Patient 4Patient 6Patient 8Patient 9 Time

Inputs Outputs Goods Services Resources Labor & Capital Process Goods Services Resources Labor & Capital Figure 2.6: The Process View of an Organization Flow units (raw material, customers)

7:008:009:0010:0011:0012:0013:0014:0015:0016:0017:0018:00 Figure 2.7: Cumulative In-flow and Out-flow Flow Time Inventory Inventory=Cumulative Inflow – Cumulative Outflow Cumulative Inflow Cumulative Outflow Time Patients

Figure 2.8.: Relationship between Inventory Turns and Gross Margins Retailer A Retailer B

Time Cumulative Number of patients 1.5 Patients Figure 2.9: Pipeline Inventory 7:008:009:0010: hours 11:0012:

Time Tons of Beets Inventory Total Beets Received (In 000’s) Total Beets Processed Figure 2.10: Seasonal inventory - Sugar End of Harvest

Inventory Days New shipment arrives Figure 2.11: Cycle Inventory

Job Shop Batch Process Worker-paced line Machine-paced line Continuous process Low Volume (unique) Medium Volume (high variety) High Volume (lower variety) Very high volume (standardized) Utilization of fixed capital generally too low Unit variable costs generally too high Commercial Printer Apparel Production High volume Auto assembly Oil refinery Figure 2.14: Product-Process Matrix (Hayes and Wheelwright) Low volume Auto Assembly