“…Many subsequent studies considered this detection problem as a classification problem and focused on the extraction of various features and the design of classifiers. These features include entropy [9][10][11][12][13], mean and/or median (with or without normalization), root mean square and/or variance [14][15][16], quantiles [16,17], median absolute deviation [10,16,17], coefficients of wavelet transformation [12,13], Markov score [18] of RRI and/or ΔRRI, or a combination of several features [10,11,16,19,20]. In recent studies, deep learning algorithms such as long short-term memory (LSTM) [21,22], and others [20,[23][24][25] have been used to process original signals without feature extraction.…”