“…For the IHR, methods include time-frequency (TF) analyses (Gil et al, 2010; Mullan et al, 2015; Wu et al, 2016), adaptive filtering (Yousefi et al, 2014; Khan et al, 2015; Murthy et al, 2015; Schack et al, 2015; Mashhadi et al, 2016), Kalman filter (Frigo et al, 2015), sparse spectrum reconstruction (Zhang, 2015), blind source separation (Wedekind et al, 2015), a Bayesian approach (D'souza et al, 2015; Sun and Zhang, 2015), correntropy spectral density (CSD) (Garde et al, 2014), empirical mode decomposition (EMD) (Zhang et al, 2015), model fitting (Wadehn et al, 2015), deep learning (Jindal, 2016), fusion approaches (Temko, 2015; Zhu S. et al, 2015), etc. For the IRR, efforts include TF analysis (Chon et al, 2009; Orini et al, 2011; Dehkordi et al, 2015), sparse signal reconstruction (Zong and Jafari, 2015; Zhang and Ding, 2016), neural network (Johansson, 2003), modified multi-scale principal component analysis (Madhav et al, 2013), independent component analysis (Zhou et al, 2006), time-varying autoregressive regression (Lee and Chon, 2010b,a), fusion approaches (Karlen et al, 2013; Cernat et al, 2015), pulse-width variability (Lazaro et al, 2013; Cernat et al, 2014), CSD (Pelaez-Coca et al, 2013; Garde et al, 2014), EMD (Garde et al, 2013), a Bayesian approach (Pimentel et al, 2015; Zhu T. et al, 2015), etc.…”