Table 6 Quantitative feature retention vs. Compression ratio.

From: Fault prediction of aircraft engine based on adaptive hybrid sampling and BiLSTM

CR

Time-Domain Similarity (Cross-Corr.)

Spectral Energy Retained (%)

Detectable Fault Types

0.1

0.92

95%

All (incl. micro-cracks < 0.2 ms)

0.2

0.88

90%

Bearing spalls, gear tooth fractures

0.3

0.81

83%

Macro-faults (> 1 ms duration)

0.4

0.75

72%

Severe imbalances (low-frequency)

0.5

0.68

60%

Only gross malfunctions