Table 3.

Comparison of the main relevant previous research studies.

References	Techniques	10-fold CV	Dataset	ACC%
Guo et al., 2010	DWT and line length, ANN	no	{Z}-{S}	100
			{FNOZ}-{S}	97.7
Gandhi et al., 2011	DWT, energy and std, SVM, NN	yes	{FNOZ}-{S}	95.4
Nicolaou and Georgiou, 2012	Permutation entropy, SVM	no	{Z}-{S}	93.5
			{O}-{S}	82.8
			{N}-{S}	88.0
			{F}-{S}	79.94
			{FNOZ}-{S}	86.1
Alam and Bhuiyan, 2013	EMD, higher order moments, ANN	no	{O}-{S}	100
			{F}-{S}	100
			{FN}-{OZ}-{S}	80
Samiee et al., 2015	Rational short time Fourier	no	{Z}-{S}	99.8
			{O}-{S}	99.3
			{N}-{S}	98.5
			{F}-{S}	94.9
			{FNOZ}-{S}	98.1
Swami et al., 2016	DTCWT, energy an std, Shannon entropy features, RNN	yes	{Z}-{S}	100
			{O}-{S}	98.89
			{N}-{S}	98.72
			{F}-{S}	93.3
			{ZO}-{S}	99.1
			{NF}-{S}	95.1
			{FNOZ}-{S}	95.2
Sharma et al., 2017	ATFFWT and FD, LS-SVM	yes	{Z}-{S}	100
			{O}-{S}	100
			{N}-{S}	99
			{F}-{S}	98.5
			{ZO}-{S}	100
			{NF}-{S}	98.6
			{ZO}-{NF}	92.5
			{FNOZ}-{S}	99.2
Yuanfa Wang et al., 2018	DWT, SVM	no	{FN}-{OZ}-{S}	93.9
This work	STFT, mean energy std and PCA, RF and GSO	yes	{Z}-{S}	100
			{O}-{S}	100
			{N}-{S}	98.5
			{F}-{S}	98.1
			{ZO}-{S}	100
			{NF}-{S}	98.2
			{ZO}-{NF}	93.2
			{FNOZ}-{S}	98.5
			{FN}-{OZ}-{S}	96.7