Table 2.

Recognition rates of single feature.

Entropy	Ship–① (%)	Ship–② (%)	Ship–③ (%)	Ship–④ (%)	Average (%)
PE	97.33	82	98.67	71.56	87.39
DE	35.11	100	52	94.89	70.5
FDE	37.33	99.78	53.78	93.11	71
RDE	34.89	100	56.44	96.22	71.89
SlEn	88.44	99.78	97.11	97.56	95.72