In this work we study a relation between a fuzzy semigroups and fuzzy dynamical systems. Some concepts about stability are introduced to evaluate a fuzzy semigroups. Several examples are given to illustrate the obtained results.

This study focuses on the problem of stability (with respect to changes of centres of fuzzy parameters) of the solution in Fuzzy Linear Programming (FLP) problems with symmetrical triangular fuzzy numbers and extended operations and inequalities.

In this paper, we define the notion of (dual) multi-fuzzy normedspaces and describe some properties of them. We then investigate Ulam-Hyers stability of Jensen's functional equation for mappings from linear spaces into  multi-fuzzy normed spaces. We establish an asymptotic behavior of the Jensen equation in the framework of multi-fuzzy normed spaces.

Stability of a fuzzy control system is closely related to the analytical structure of the fuzzy controller, which is determined by its components such as input and output fuzzy sets and fuzzy rules. We first characterize the mathematical input–output structure of fuzzy controllers and then utilize the structure characteristics to advance stability analysis. We study how the components of a gene...

In this paper fuzzy bi-directional associative memory (BAM) neural networks with constant delays are considered. Some sufficient conditions for existence and global exponential stability of unique equilibrium point are established by using fixed point theorem and differential inequality techniques. The results obtained are easily checked to guarantee existence, uniqueness and global exponential...

This study develops fuzzy control that is designed with sliding modes to achieve stability of the fuzzy controller. Fuzzy control is formulated in the form of variable structure system (VSS) control. In contrast to previous works in which Lyapunov functions are used to examine the stability, the current study investigates the stability of fuzzy control from the viewpoints of differential geomet...

Power system transient stability is one of the most challenging technical areas in electric power industry. Thyristorcontrolled series compensation (TCSC) is expected to improve transient stability and damp power oscillations. TCSC control in power system transients is a nonlinear control problem. This paper presents a T–S-model-based fuzzy control scheme and a systematic design method for the ...

Introduction A classical question in the theory of functional equations is “when is it true that a mapping, which approximately satisfies a functional equation, must be somehow close to an exact solution of the equation?”. Such a problem, called a stability problem of the functional equation, was formulated by Ulam [1] in 1940. In the next year, Hyers [2] gave a partial solution of Ulam’s probl...

We investigate local robust stability of fuzzy neural networks FNNs with time-varying and S-type distributed delays. We derive some sufficient conditions for local robust stability of equilibrium points and estimate attracting domains of equilibrium points except unstable equilibrium points. Our results not only show local robust stability of equilibrium points but also allow much broader appli...

The global exponential stability of the neural networks is investigated for a new fuzzy cellular neural networks with time-varying delays. A novel delay-dependent stability criterion is derived based on Lyapunov stability theory and the linear matrix inequality. By transforming the fuzzy logic terms with time-delay, our criteria are less conservative than existing results. Two examples are prov...