Operations Research present state and future trends are analyzed from the Fuzzy-Sets-based methodologies point of view. Then, in a more particular perspective, some speciic topics of Fuzzy-Sets-based models in Operations Research, such as fuzzy optimization, preference modelling, linguistic modelling and decision models, as well as some other well known Operations Research speciic topics, are a...

This paper gives a short introduction into Fuzzy Set Theory, presents an overview on fuzzy controllers, and discusses possible combinations between fuzzy controllers and neural networks. Fuzzy Sets suggested by L.A. Zadeh 32] ooer a possibility to formally describe linguistic expressions like tall, fast, medium, etc., and to operate on them. Fuzzy controllers use fuzzy sets to represent linguis...

A fuzzy multipurpose decision making problem, where the information about the alternatives provided by the experts can be presented by means of diierent preference representation structures, is studied. Assuming that the information can be represented by means of preference orderings, utility functions and fuzzy preference relations, a general multipurpose decision making model is managed to co...

In [14] Yager and Filev introduced the Induced Ordered Weighted Averaging (IOWA) operator. In this paper, we provide some IOWA operators to aggregate fuzzy preference relations in group decision making problems. In particular, we present the Importance IOWA (I-IOWA) operator, the Consistency IOWA (C-IOWA) operator and the Preference IOWA (P-IOWA) operator. We also provide a procedure to deal wi...

Interval fuzzy preference relations can be useful to express decision makers' preferences in group decision-making problems. Usually, we apply a selection process and a consensus process to solve a group decision situation. In this paper, we present a consensus model for group decisionmaking problems with interval fuzzy preference relations. This model is based on two consensus criteria, a cons...

A visual consensus feedback mechanism for group decision making (GDM) problems with complementary linguistic preference relations is presented. Linguistic preferences are modelled using triangular fuzzy membership functions, and the concepts of similarity degree (SD) between two experts as well as the proximity degree (PD) between an expert and the rest of experts in the group are defined and u...

  Multiple criteria decision making (MCDM) problem is one of the famous different kinds of decision making problems. In more cases in real situations, determining the exact values for MCDM problems is difficult or impossible. So, the values of alternatives with respect to the criteria or / and the values of criteria weights, are considered as fuzzy values (fuzzy numbers). In such conditions, th...

An important issue to bear in mind in Group Decision Making situations is that of consistency. However, the expression of consistent preferences is often a very difficult task for the decision makers, specially in decision problems with a high number of alternatives and when decision makers use fuzzy preference relations to provide their opinions. It leads to situations where a decision maker m...