“…However, if a non-affine model (for example nonlinear rational model or called total nonlinear model, see Zhu, Wang, Zhao, Li, & Billingse (2015)) or with time-delay is considered, it is still an open and challenging issue for future directions. The problems will be investigated via some novel approaches, e.g., U-block model-based design (Zhu, Zhao, & Zhang, 2016) in our future research.…”