In this paper we classify fuzzy subgroups of the dihedral group $D_{pqrs}$  for distinct primes  $p$, $q$, $r$ and $s$. This follows similar work we have done on distinct fuzzy subgroups of some dihedral groups.We present formulae for the number of (i) distinct maximal chains of subgroups, (ii) distinct fuzzy subgroups and (iii) non-isomorphic classes of fuzzy subgroups under our chosen equival...

In this paper, the fuzzy systems with multiple non-commensurate time delays are considered. First, the observer-based state feedback fuzzy controllers are proposed. Based on the delay-dependent Lyapunov functional approach, the delay-dependent control design method is derived under which the parallel-distributed fuzzy control can stabilize the whole fuzzy time-delay system asymptotically. Final...

We formulate a stopping problem for dynamic fuzzy systems concerning with fuzzy decision environment. It could be regarded as a natural fuzzification of non-fuzzy stopping problem with a deterministic dynamic system. The validity of the approach by α-cuts of fuzzy sets will be discussed in constructing One-step Look Ahead policy of an optimal fuzzy stopping time. A numerical example is given to...

Keeping in the view the non-probabilistic nature of experiment, we introduced some new generalized exponential fuzzy entropy involving one or more real parameters and to check their authenticity, the essential properties of these measures have been studied. Introduced fuzzy entropies contain several other existing parametric and non-parametric measures of fuzzy entropies defined by De Luca and ...

This paper presents a string matching experience using deformed fuzzy automata for the recognition of imperfect strings. We propose an algorithm based on a deformed fuzzy automaton that calculates a similarity value between strings having a non-limited number of edition errors. Different selections of the fuzzy operators for computing the deformed fuzzy automaton transitions allows to obtain di...

If all we know about normalized fuzzy sets is which set is a subset of which, will we be able to detect crisp sets? It is known that we can do it if we allow all possible fuzzy sets, including non-normalized ones. In this paper, we show that a similar detection is possible if we only allow normalized fuzzy sets. We also show that we can detect type-1 fuzzy sets based on the subsethood ordering ...

In this paper, a new method is proposed to find the fuzzy optimal solution of fully fuzzy linear programming (abbreviated to FFLP) problems. Also, we employ linear programming (LP) with equality constraints to find a non-negative fuzzy number vector x̃ which satisfies Ãx̃ = b̃, where à is a fuzzy number matrix. Then we investigate the existence of a positive solution of fully fuzzy linear system (...

This paper describes the stepper motor position control implemented using a novel nonsingleton type-1 fuzzy logic system to update the gains of the professional proportional-integral-derivative controller running on ATMEGA 2560 microcontroller. In this work, three controllers are compared: a) the professional proportional-integral-derivative controller, b) the type-1 singleton fuzzy logic syste...

Different types of controlling methods are used in switched mode dc-dc converters and the controller which is simple and of low cost is always in demand. The different controllers used are PI controller, PID controller and Fuzzy logic controller. PI and PID controllers do not give good performance in non linear conditions. Fuzzy logic controller is a non linear controller which do not need exac...

The main objective of this paper is to deal with some properties of interest in two types of fuzzy ordered proximal contractions of cyclic self-mappings T integrated in a pair (g, T) of mappings. In particular, g is a non-contractive fuzzy self-mapping, in the framework of non-Archimedean ordered fuzzy complete metric spaces and T is a p-cyclic proximal contraction. Two types of such contractio...