Table 4.
Parameters tuned by the GA for each SAE structure that is considered for each domain of analysis for the vibration signals used in the stacked AE; all technology materials.
| Material | Feature Domain | Hyperparameters | ||
|---|---|---|---|---|
|
L2 Regularization |
Sparsity Regularizatio |
Sparsity Proportion |
||
| Metallic | Time (T1 group) | 1.31 × 10−5 | 7.384 × 10−5 | 0.664 |
| Frequency (F1 group) | 1.616 × 10−5 | 5.761 × 10−5 | 0.655 | |
| Time–Frequency (TF1 group) | 3.250 × 10−5 | 7.164 × 10−5 | 0.779 | |
| Ceramic | Time (T1 group) | 2.090 × 10−5 | 8.037 × 10−5 | 0.132 |
| Frequency (F1 group) | 2.879 × 10−5 | 1.407 × 10−5 | 0.479 | |
| Time–Frequency (TF1 group) | 2.213 × 10−5 | 5.277 × 10−5 | 0.854 | |
| Hybrid | Time (T1 group) | 2.212 × 10−5 | 7.785 × 10−5 | 0.176 |
| Frequency (F1 group) | 1.276 × 10−5 | 2.406 × 10−5 | 0.560 | |
| Time–Frequency (TF1 group) | 1.064 × 10−5 | 4.435 × 10−5 | 0.240 | |