“…This technique, which is based on the chaos theory, uses delay coordinate theorem to represent chaotic signals such as electrocardiogram (ECG), electroencephalogram (EEG), and the speech signal (Sharma and Pachori, 2015;Zhou et al, 2015;Koulaouzidis et al, 2015;Lee et al, 2014;Al-Fahoum and Qasaimeh, 2013;Thasleema et al, 2012;Nejadgholi et al, 2011;Johnson et al, 2005). Researchers have successfully implemented RPS-based feature extraction approaches in verity of speech applications (e.g., speech recognition, phoneme classification, pitch mark detection and speech enhancement) (Sun Contents , 2007Povinelli et al, 2006;Hagmüller and Kubin, 2006).…”