Research on Recognition of Quiet Period of Sandstone Acoustic Emission Based on Four Machine Learning Algorithms

Table 4

Energy ratio of each subband.

Subband (kHz)	0~62.5	62.5~125	187.5~250	125~187.5	375~437.5	437.5~500	312.5~375	250~312.5
Ratio (%)	1	8.9	25.5	21.5	0.1	0.61	29.7	10.4