“…In addition, critical damping (Adhikari, 2005;Lázaro, 2019aLázaro, , 2019b, closed-form solution for free vibration (García-Barruetabeña et al, 2012), and other dynamic characteristics of the non-viscous damping linear (Adhikari, 2008) and non-linear (Sieber et al, 2008) system are analyzed by researchers in recent years. Some researchers proposed identification methods such as linear least square method (Adhikari and Woodhouse, 2001), parameter iterative method (Pan and Wang, 2015), and Kalamn filtering method (Reggio et al, 2013) for non-viscous damping system in frequency domain (Su et al, 2019) and in time domain (Shen et al, 2020).…”