1. Operations Management Operations Scheduling
Manufacturing Execution Systems
Equipment Scheduling
Work Centers
Priority rules
Johnson’s rule
Backward / Forward scheduling
Workforce Scheduling
MBA.782.Operations.Scheduling

2. Work flow is driven by a schedule
Oper. Sched Manufacturing Execution Systems
Work flow = Cash flow
Work flow is driven by a schedule
____ % of time actually working; ____ % of time waiting in queues
Schedule equipment and workforce
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3. Becomes exceedingly complex because....
Oper. Sched Equipment Scheduling
Becomes exceedingly complex because....
Unpredictability of demand for all resources
Variability of throughput times
Tradeoffs among:
Utilization of people and equipment vs. Work in Process vs. ability to meet promised delivery dates
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4. where a particular type of work is done.
Equip. Sched Work Centers
A work center is an area in a business in which productive resources are organized and work is completed.
where a particular type of work is done.
Finite / infinite ____________
backward / forward _____________
machine and/or labor ___________
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5. ___________ for the resource of interest
Equip. Sched Definitions
Queue time
___________ for the resource of interest
Flow time = operation time + queue time
time for a job to _______________ the process
Lateness = ( Flow time - Due date ) +
Completion time (aka, ______________ )
finish time of last job - start time of first job
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6. Meeting ____ ______ of customers or downstream operations.
Equip. Sched Schedule Performance Measures
Meeting ____ ______ of customers or downstream operations.
Minimizing the flow time
the time a job _________ in the process
Minimizing work-in-process inventory.
Minimizing _____ ______ of machines or workers.
Maximize machine utilization
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7. Allocating orders, equipment, and personnel.
Equip. Sched Scheduling Activities
Allocating orders, equipment, and personnel.
Determining the ____________ of order performance.
Schedule jobs as a _________ with process stages back to back.
Re-schedule every day.
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8. Used for n-Jobs on One Machine Local Priority Rules
Equip. Sched Priority Rules and Techniques
Used for n-Jobs on One Machine
Local Priority Rules
schedule jobs according to their effect on the _____________________ workstation
Global Priority Rules
sequence jobs according to their effect on ____________ work requirements
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9. Suppose these four jobs arrive for processing on one machine:
Local Priority Rules First Come, First Serve (FCFS)
Suppose these four jobs arrive for processing on one machine:
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10. The job with the shortest processing time is processed first
Local Priority Rules Shortest Operation Time (SOT)
The job with the shortest processing time is processed first
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11. Schedule job with smallest slack first
Local Priority Rules Slack Time Remaining (STR)
Schedule job with smallest slack first
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12. MBA.782.Operations.Scheduling

13. Sequence: ____ , ____ , ____ , ____
Global Priority Rules Critical Ratio (CR)
Sequence: ____ , ____ , ____ , ____
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14. Sequence: ____ , ____ , ____ , ____
Global Priority Rules. Dynamic Slack / Operation Remaining
Sequence: ____ , ____ , ____ , ____
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15. Job A Job B Job C Jobs (N = 3) Saw Drill
Oper. Sched. Johnson’s Rule
Used to schedule n-jobs through 2 sequential machines
Jobs (N = 3)
Saw
Drill
Job A
Job B
Job C
© 1995 Corel Corp.
© 1995 Corel Corp.
MBA.782.Operations.Scheduling

16. Once a job is scheduled, eliminate it.
Oper. Sched. Johnson’s Rule
All jobs are to be listed, and the time required on each machine is shown.
Select the job with the shortest activity time. If the shortest time lies with the first machine, the job is scheduled first; if with the second machine, the job is scheduled last.
Once a job is scheduled, eliminate it.
Apply steps 2-3 to the remaining jobs, working toward the center of the sequence.
MBA.782.Operations.Scheduling

17. Jobs to be sent through a 2-machine sequence...
Oper. Sched. Johnson’s Rule
Jobs to be sent through a 2-machine sequence...
Job Saw Time Drill Time
A 5 2
B 3 6
C 8 4 D E
MBA.782.Operations.Scheduling

18. schedule the ____________ possible starting time
Oper. Sched. Forward and Backward Scheduling
Forward Scheduling
schedule the ____________ possible starting time
due dates determined by internal scheduler
Backward Scheduling
determine the _____________ possible starting time
for externally set due dates
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19. Oper. Sched. Forward and Backward Scheduling
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20. Oper. Sched. Forward and Backward Scheduling
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21. forecasted staffing levels
Oper. Sched. Workforce Scheduling in Services
Need to know
forecasted staffing levels
specific skills needed during the time-frame
work-hour constraints
Consecutive days-off requirements
methods exist to provide the _____ schedule
Complex scheduling situations
computer programs used to find ______________ schedules, given many constraints
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22. Oper. Sched. Scheduling Consecutive Days Off
Objective
find the schedule that minimizes the number of five-day workers with two consecutive days off, subject to the demands of the daily staffing schedule
Procedure
given the total number of workers needed each day, create a schedule by adding one worker at a time
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23. Oper. Sched. Scheduling Consecutive Days Off
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24. Concepts / Terminology Review Lecture notes Recommended Problems
Topic Title Chapter Wrap-Up
Read Chapter 15
Concepts / Terminology
Review Lecture notes
Recommended Problems
MBA.782.Operations.Scheduling

25. Principles of Work Center Scheduling
1. There is a direct equivalence between work flow and cash flow.
2. The effectiveness of any job shop should be measured by speed of flow through the shop.
3. Schedule jobs as a string, with process steps back-to-back.
4. A job once started should not be interrupted.
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26. Principles of Job Shop Scheduling (Continued)
5. Speed of flow is most efficiently achieved by focusing on bottleneck work centers and jobs.
6. Reschedule every day.
7. Obtain feedback each day on jobs that are not completed at each work center.
8. Match work center input information to what the worker can actually do.
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27. Principles of Job Shop Scheduling (Continued)
9. When seeking improvement in output, look for incompatibility between engineering design and process execution.
10. Certainty of standards, routings, and so forth is not possible in a job shop, but always work towards achieving it.
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