Chapter 16 & 9

1. Chapter 16 & 9 Scheduling Work & Employees

2. SchedulingOutline What needs to be scheduled? • doctor’s office, restaurant, mfg. plant, hospital • employees vs. products Gantt charts Dispatching (sequencing) rules for scheduling work Scheduling employees

3. Shop floor control includes: • assigning a priority to each order • issuing dispatching lists to each work center (what and when to produce) • keeping WIP inventory updated • providing input-output control for all work centers • monitoring efficiency, utilization, and productivity of workers and machines

4. Scheduling (Dispatching/Sequencing) Rules FCFS – First Come, First Served SPT – Shortest Processing Time EDD – Earliest Due Date Least Slack (LS) slack = (time until due date) – (remaining lead time)  process job with smallest slack first Critical Ratio (CR) CR = (time until due date) / (remaining lead time)  process job with smallest CR first

5. Scheduling Rules Example currently day 50; 5 jobs at a machine

6. Gantt Chart weeks of processing time work order #mach. Amach. Bmach. Ctotal 34 4 2 1 35 1 3 1 36 2 2 2 37 1 1 2

7. 34 36 37 A 35 15 weeks B 34 35 36 37 C 34 35 36 37 Gantt ChartFCFS: 34, 35, 36, 37

8. 35 37 36 34 A 11 weeks B 37 35 36 34 C 37 35 36 34 Gantt ChartSPT: 37, 35, 36, 34

9. Work-Shift Scheduling Rule(work 5 days, 2 consecutive days off) Minimum # of employees needed

10. Work-Shift Scheduling Rule(work 5 days, any 2 days off) Minimum # of employees needed

11. Work-Shift Scheduling Rule(work 4 days, 3 consecutive days off) Minimum # of employees needed