Search results for "Fuzzy set"
showing 10 items of 197 documents
Experimental Comparison of Type-1 and Type-2 Fuzzy Logic Controllers for the Control of Level and Temperature in a Vessel
2011
Abstract The objective of this experimental study is to compare the performance of type-1 and type-2 fuzzy logic controllers on a real system where the control of liquid level and temperature are considered. By the use of genetic algorithms it is possible to optimize the fuzzy sets of each fuzzy controller assuring high control performance. The experimental results show that a better control in terms of robustness can be achieved by type-2 fuzzy logic controllers.
A Fuzzy Approach to the Role of Symmetry in Shape Formation: The Illusion of the Scalene Triangle
2009
The main purposes of this work are to demonstrate the role of directional symmetry as a second order principle that polarizes the perception of the shape and to show how this preference can be easily encoded in an algorithm using a fuzzy operator for symmetry detection. The role of grouping in influencing shape perception and the role of directional symmetry was demonstrated through small triangles that create a large triangle. The specific questions answered in the psychophysical experiments were the following: Can the grouping by similarity influence both the pointing and the shape of the small and the large isosceles triangles? Conversely, can the shape of the large triangle influence th…
Obtaining the Compatibility between Musicians Using Soft Computing
2010
Modeling the musical notes as fuzzy sets provides a flexible framework which better explains musicians’ daily practices. Taking into account one of the characteristics of the sound: the pitch (the frequency of a sound as perceived by human ear), a similarity relation between two notes can be defined. We call this relation compatibility. In the present work, we propose a method to asses the compatibility between musicians based on the compatibility of their interpretations of a given composition. In order to aggregate the compatibilities between the notes offered and then obtain the compatibility between musicians, we make use of an OWA operator. We illustrate our approach with a numerical e…
Fuzziness and social life: Informal notions, formal definitions
2012
A clear bidirectional path exists between everyday social and cultural life and the formal notions of uncertainty. If in recent times there has been a resurgence of the contribution of the formal notions of fuzziness and vagueness to disciplines such as aesthetics, medicine and more generally humanities, it is also true that concepts and phenomena from everyday reality are continually and usefully reused in order to build formal definitions that are more akin to the essence of things. In this paper, some notions connected with the handling of uncertainty, and particularly with FST, are outlined with the aim of benefitting the spontaneous emergence of new paths toward an unified theory of un…
Soft computing-based aggregation methods for human resource management
2008
Abstract We are interested in the personnel selection problem. We have developed a flexible decision support system to help managers in their decision-making functions. This DSS simulates experts’ evaluations using ordered weighted average (OWA) aggregation operators, which assign different weights to different selection criteria. Moreover, we show an aggregation model based on efficiency analysis to put the candidates into an order.
Artificial Vision and Soft Computing
1999
The term soft-computing has been introduced by Zadeh in 1994. Soft-computing provides an appropriate paradigm to program malleable and smooth concepts. For example, it can be used to introduce flexibility in artificial systems to improve their Intelligent Quotient. The aim of this paper is to describe the applicability of soft-computing to artificial vision problems. Good performance of this approach is assured by the fact that digital images are examples of fuzzy entities, where shapes are not always describable by exact equations and their approximation can be very complex.
Some reflections on Fuzzy Set Theory as an Experimental Science
2014
The aim of this paper is to open a critical discussion on the claim, recently presented in the community and especially heralded by Enric Trillas, that fuzzy logic should be seen as an “experimental science”. The first interesting aspect of such remark is whether and in which way such position has consequences on the real development of the research, or if it is simply a (different) way of looking at the same phenomenon. As a consequence, we investigate the possible connection to Zadeh’s distiction between Fuzzy logic in a restricted sense and in a general sense. We shall argue that Trillas’s claim not only strongly supports the necessity for such a distinction, but provides a path of inves…
Concepts, Theories, and Applications: The Role of “Experimentation” (and “Context”) for Formalizing New Ideas along Innovative Avenues
2012
The main aim of this paper is to present a few general ideas preliminary to an assessment of the role that a correct interchange between the elaboration of new theories and an open minded experimentation can have in the development of new fields of investigation. Although many of the reflections and remarks that follow will be of a very broad type, the reference background of all the paper will be, in general, the composite field of information sciences and, more specifically, the innovative concepts and approaches introduced by fuzzy sets theory. Abe Mamdani’s work can certainly be considered as an outstanding example of the way in which these innovations arose and, subsequently, flourishe…
Applying Cathegorical Metrics on Fuzzy Systems
2007
This work analyzes the categorical metrics usage on a very specific subset of Intelligent Systems: Fuzzy Systems. Several characteristics for such systems must be carefully evaluated when metrics and indicators are defined, in order to consider the fuzzy essence as part of the evaluation result. A set of metrics and indicators are defined and applied to the classical inverted pendulum problem. The paper does not intend to provide an exhaustive analysis of the quality evaluation on soft computing problem. It just presents a way to start the study of quality measure in that area.
On Some “family resemblances” of Fuzzy Set Theory and Human Sciences
2011
The aim of this paper is to underline the importance of detecting similarities or at least, ‘family resemblances’ among different fields of investigation. As a matter of fact, the attention will be focused mainly on fuzzy sets and a few features of human sciences; however, I hope that the arguments provided and the general context outlined will show that the problem of picking up (dis)similarities among different disciplines is of a more general interest. Usually strong dichotomies guide out attempts at understanding the paths along which scientific research proceed; i.e., soft versus hard sciences, humanities versus the sciences of nature, Naturwissenschaften versus Geisteswissenschaften, …