Production Scheduling Nahmias, Chapter 8 ( D t lj l i ) (sv ...

A Sequencing Example (III)
• Use a Greedy Approach:
– Consider all pairwise interchanges
– Ch Choose one that th t reduces d average tardiness t di by b maximum i
amount
– Continue until no further improvement is possible
A Sequencing Example (IV)
• First Interchange: Exchange jobs 4 and 5.
Job Due Completion
Number Family Date Time Lateness
1 1 500 5.00 500 5.00 000 0.00
2 1 6.00 6.00 0.00
3 1 10.00 7.00 -3.00
5 1 15.00 8.00 -7.00
4 2 13.00 13.00 0.00
6 2 15.00 14.00 -1.00
7 1 22.00 19.00 -3.00
8 2 22.00 24.00 2.00
9 1 23.00 29.00 6.00
10 3 29.00 34.00 5.00
11 2 30 30.00 00 39 39.00 00 900 9.00
12 2 31.00 40.00 9.00
13 3 32.00 45.00 13.00
14 3 32.00 46.00 14.00
15 3 33.00 47.00 14.00
16 3 40.00 48.00 8.00
• Average Tardiness: 5.0 (reduction of 5.375!)
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20
10