“…In the literature, different forms have been proposed to approximate the feasible parameter set of integer models, such as ellipsoids (Belforte et al, 1990; Deller et al, 1994; Fogel and Huang, 1982), orthotopes (Cerone et al, 2011; Messaoud and Favier, 1993; Milanese and Belforte, 1982), zonotopes (Blesa et al, 2011; Bravo et al, 2006; Mo and Norton, 1990) and orthonormal basis functions (Casini et al, 2003). For fractional models, few studies have treated set-membership parameter estimation using an ellipsoidal approximation (Amairi, 2016) or a parallelotope approximation (Amairi et al, 2012). To improve the estimation algorithms of uncertain fractional systems for efficient applications in control (Saidi et al, 2015; Yakoub et al, 2017) and diagnosis, a new orthotopic approach has been developed recently (Hamdi et al, 2016).…”