We investigate linear operators between C?-algebras which approximately preserve involution and orthogonality, the latter meaning that for some ?>0 we have ??(x)?(y)????x??y? all positive x,y with xy=0. establish structural properties of such maps concerning approximate Jordan-like equations almost commutation relations. In situations (e.g. when codomain is finite-dimensional), show ? can be ap...

This paper proposes a new perspective in the enhancement of the closed-loop tracking performance by using the first-order hold (FOH) sensing technique. Firstly, the literature review and fundamentals of the FOH are outlined. Secondly, the performance of the most commonly used zero-order hold (ZOH) and that of the FOH are compared. Lastly, the detailed implementation of the FOH on a pendulum tra...