The paper deals with both theoretical and application aspects concerning Iterative Feedback Tuning (IFT) algorithms in the design of a class of fuzzy control systems employing Mamdani-type PI-fuzzy controllers. The presentation is focused on twodegree-of-freedom fuzzy control system structures resulting in one design method. The stability analysis approach based on Popov’s hyperstability theory...

In this paper, we introduce $n$-variables mappings which are cubic in each variable. We show that such satisfy a functional equation. The main purpose is to extend the applications of fixed point method establish Hyers-Ulam stability for multi-cubic mappings. As consequence, prove equation can be hyperstable.

This paper relates properties of operators with the well-known concepts of positive realness and passivity properties in dynamic systems and their associate transfer functions. Those concepts together with very close related ones are first examined from a physical point of view. Then, they are related with hyperstability and properties of transfer functions while the hyperstability theorem is r...

The study of stability problems of functional equations was motivated by a question of S.M. Ulam asked in 1940. The first result giving answer to this question is due to D.H. Hyers. Subsequently, his result was extended and generalized in several ways.We prove some hyperstability results for the equation g(ax+by)+g(cx+dy)=Ag(x)+Bg(y)on restricted domain. Namely, we show, under some weak natural...

In this manuscript, we study the properties and equivalence results for different forms of quadratic functional equations. Using Brzdȩk Ciepliński fixed-point approach, investigate generalized Hyers–Ulam–Rassias stability 3-variables equation in setting 2-Banach space. Also, obtain some hyperstability equation. The obtained paper extend several known literature to

In this work, by using some orthogonally fixed point theorem, we prove the stability and hyperstability of C ∗ -ternary Jordan homomorphisms between id="M3"> Banach algebras id="M4"> derivations functional equation on id="M5"> algebras.

Modern aircraft control systems contain the so-called rate limiter elements which are in fact incorporating the saturation function which is a bounded nonlinearity. In certain critical cases the so-called sector rotation a standard procedure in absolute stability leads to the fact that the sector conditions are broken outside a bounded domain. In order to apply standard results of the absolute ...