Research Article
A Hybrid Genetic Algorithm to Minimize Total Tardiness for Unrelated Parallel Machine Scheduling with Precedence Constraints
Table 4
Performance of the HGA for small-sized instances.
| No. of group |
| B&B | HGA | | | | Mean CPU time (s) | | Mean CPU time (s) | Gap (%) |
| 1 | 9 | 4 | 39 | 1.5 | 39 | 0.4 | 0 | 2 | 9 | 3 | 72 | 5.5 | 72 | 0.6 | 0 | 3 | 9 | 2 | 61 | 72.7 | 61 | 0.7 | 0 | 4 | 10 | 4 | 68 | 9.3 | 68 | 7.1 | 0 | 5 | 10 | 3 | 63 | 2.9 | 63 | 5.7 | 0 | 6 | 10 | 2 | 64 | 18.7 | 65 | 8.4 | 1.6 | 7 | 11 | 4 | 32 | 86.2 | 32 | 2,3 | 0 | 8 | 11 | 3 | 123 | 2.8 | 124 | 0.6 | 0.8 | 9 | 11 | 2 | 129 | 20.5 | 129 | 1.9 | 0 |
| Average | | | | 24.5 | | 3.1 | 0.3 |
|
|