1. Scheduling

2. What is scheduling
In a production system, it is the timing and sequencing of the use of specific resources in the system and is the final step in the decision making process of an organization before the actual transformation processes begin.

3. Scheduling Manufacturing Operations
Build A
A Done
Build B
B Done
Build C
C Done
Build D
Ship
JAN
FEB
MAR
APR
MAY
JUN
On time!
High-volume
Intermediate- volume
Low-volume
Service operations

4. High-Volume Systems
Flow system: High-volume system with Standardized equipment and activities
Flow-shop scheduling: Scheduling for high-volume flow system
Work Center #1
Work Center #2
Output

5. High-Volume Success Factors
Process and product design
Preventive maintenance
Rapid repair when breakdown occurs
Optimal product mixes
Minimization of quality problems
Reliability and timing of supplies

6. Intermediate-Volume Systems
Outputs are between standardized high-volume systems and made-to-order job shops
Economic run size:

7. Scheduling Low-Volume Systems
Loading - assignment of jobs to process centers
Sequencing - determining the order in which jobs will be processed

8. Loading
Gantt chart - used as a visual aid for loading and scheduling

9. Assignment Problem Jobs Workers
Assigning jobs to workers. There is a cost associated with a worker completing a certain job. The objective is to finish all the jobs by the workers so that the total cost is minimized.
An optimal solution can be found by the Hungarian Method.

10. Sequencing
Sequencing: Determine the order in which jobs at a work center will be processed.
Workstation: An area where one person works, usually with special equipment, on a specialized job.

11. Sequencing
Priority rules: Simple heuristics used to select the order in which jobs will be processed.
Job time: Time needed for setup and processing of a job.
Everything is #1 Priority

12. Priority Rules FCFS - first come, first served
SPT - shortest processing time
DD - due date
CR - critical ratio
S/O - slack per operation
Rush - emergency
Top Priority

13. Two Work Center Sequencing
Johnson’s Rule: technique for minimizing completion time for a group of jobs to be processed on two machines or at two work centers.
Minimizes total idle time
Several conditions must be satisfied

14. Johnson’s Rule Conditions
Job time must be known and constant
Job times must be independent of sequence
Jobs must follow same two-step sequence
Job priorities cannot be used
All units must be completed at the first work center before moving to second

15. Scheduling Service Operations
Appointment systems
Controls customer arrivals for service
Reservation systems
Estimates demand for service
Scheduling the workforce
Manages capacity for service
Scheduling multiple resources
Coordinates use of more than one resource

16. Service Operation Problems
Cannot store or inventory services
Customer service requests are random
Scheduling service involves
Customers
Workforce
Equipment