“…In this area, the literature is very rich. Characterization results on the notions of weak and exact controllability and observability, as well as strategic actuators and sensors, are established (Afifi and El Jai, 1994;Afifi et al, 2002a;2002b;2008a;Berrahmoune, 1984;Curtain and Pritchard, 1978;Curtain and Zwart, 1995;El Jai and Pritchard, 1987;Jacob and Zwart, 2001;Lions, 1968;1988;Qarai et al, 2008;Uciński and Korbicz, 1990;Zerrik, 1993;Zerrik et al, 2007). But in almost all these works, the problems considered are focused on the possibility to reach a desired state or reconstruct the state of the examined system, i.e., on studying if a system is (or not) controllable or observable, but without comparison between the input or output parameters themselves.…”