Now showing items 1-20 of 101

    • A Decomposition Theorem for T-Indistinguishability Operators : the Continuous Strict Archimedean Case 

      Boixader Ibáñez, Dionís; Recasens Ferrés, Jorge (2012)
      Conference report
      Open Access
    • A map characterizing the fuzzy points and columns of a T-indistinguishability operator 

      Boixader Ibáñez, Dionís; Recasens Ferrés, Jorge (2005-10)
      Article
      Open Access
      A new map (ΛE) between fuzzy subsets of a universe X endowed with a T-indistinguishability operator E is introduced. The main feature of ΛE is that it has the columns of E as fixed points, and thus it provides us with a ...
    • A model for CAGD using fuzzy logic 

      Jacas Moral, Juan; Monreal Pujadas, Amadeo; Recasens Ferrés, Jorge (1997-01)
      Article
      Restricted access - publisher's policy
      This paper presents a first approach to a system based on fuzzy logic for the design of curves and surfaces in the context of computer aided geometric design. Bézier curves and surfaces can be seen as particular cases of ...
    • A reformulation of entropy in the presence of indistinguishability operators 

      Recasens Ferrés, Jorge; Hernández, E (2002-06)
      Article
      Restricted access - publisher's policy
      This paper deals with the measurement of entropy when an indistinguishability relation on the set of events has been defined. Our approach states that entropy could be measured in terms of the observed distinguishability ...
    • Acciones de grupos borrosas 

      Boixader Ibáñez, Dionís; Recasens Ferrés, Jorge (2016)
      Conference report
      Open Access
      Este trabajo generaliza (fuzzifica) las acciones de un grupo sobre un conjunto para tratar situaciones donde hay imprecisión e incertidumbre. Las acciones borrosas pueden tratar la granularidad de un conjunto o incluso ...
    • Aggregating fuzzy subgroups and T-vague groups 

      Boixader Ibáñez, Dionís; Mayor, Gaspar; Recasens Ferrés, Jorge (Springer, 2018-01-01)
      Article
      Open Access
      Fuzzy subgroups and T-vague groups are interesting fuzzy algebraic structures that have been widely studied. While fuzzy subgroups fuzzify the concept of crisp subgroup, T-vague groups can be identified with quotient groups ...
    • Aggregating Fuzzy Subgroups and T-vague subgroups 

      Boixader Ibáñez, Dionís; Mayor, Gaspar; Recasens Ferrés, Jorge (Springer, 2017)
      Conference report
      Open Access
    • Aggregating T-equivalence relations 

      Mayor, Gaspar; Recasens Ferrés, Jorge (2016)
      Conference report
      Open Access
      This contribution deals with the problem of aggregating Tequivalence relations, in the sense that we are looking for functions that preserve reflexivity, symmetry, and transitivity with respect to a given t-norm T. We ...
    • Aggregation of T-transitive Relations 

      Jacas Moral, Juan; Recasens Ferrés, Jorge (Wiley InterScience, 2003-12)
      Article
      Restricted access - publisher's policy
      This article studies the aggregation of transitive fuzzy relations. We first find operators that preserve transitivity and then extend the results to aggregating operators. As special cases, means and some kind of suitable ...
    • Aggregation operators and lipschitzian conditions 

      Recasens Ferrés, Jorge (Universitat Politècnica de Catalunya. Secció de Matemàtiques i Informàtica, 2008)
      Article
      Open Access
      Lipschitzian aggregation operators with respect to the natural T - indistin- guishability operator Et and their powers, and with respect to the residuation ! T with respect to a t-norm T and its powers are studied. A ...
    • Aggregation operators and quadric hypersurfaces 

      Recasens Ferrés, Jorge (Springer, 2013)
      Article
      Open Access
      Aggregation operators that are quadric hypersurfaces are studied. The interest lays in the fact that the most popular aggregation operators are indeed quadric hypersurfaces.
    • Aggregation operators and ruled surfaces 

      Recasens Ferrés, Jorge (IOS Press, 2008)
      Conference report
      Open Access
    • Aggregation operators and the Lipschitzian condition 

      Jacas Moral, Juan; Recasens Ferrés, Jorge (IEEE Comp. Int. Soc., 2007)
      Conference report
      Open Access
      Lipschitzian and kernel aggregation operators with respect to the natural T-indistinguishability operator ET and their powers are studied. A t-norm T is proved to be ETLipschitzian, and is interpreted as a fuzzy point and ...
    • Aggregation Operators Based on Indistinguishability Operators 

      Jacas Moral, Juan; Recasens Ferrés, Jorge (Wiley InterScience, 2006-08)
      Article
      Restricted access - publisher's policy
      This article gives a new approach to aggregating assuming that there is an indistinguishability operator or similarity defined on the universe of discourse. The very simple idea is that when we want to aggregate two values ...
    • An algorithm to compute the transitive closure, a transitive approximation and a transitive opening of a fuzzy proximity 

      Garmendia Salvador, Luis; González del Campo, Ramón; López, Victoria; Recasens Ferrés, Jorge (2009-11)
      Article
      Open Access
      A method to compute the transitive closure, a transitive opening and a transitive approximation of a reflexive and symmetric fuzzy relation is given. Other previous methods in literature compute just the transitive closure, ...
    • An algorithm to compute the transitive closure, a transitive approximation and a transitive opening of a proximity 

      Garmendia Salvador, Luis; González, Ramón; Recasens Ferrés, Jorge (2008)
      Conference report
      Open Access
      A method to get the transitive closure, a transitive opening and a transitive approximation of a reflexive and symmetric fuzzy relation is presented. The method builds at the same time a binary partition tree for the output ...
    • Approximate fuzzy preorders and equivalences 

      Boixader Ibáñez, Dionís; Recasens Ferrés, Jorge (2009)
      Conference report
      Restricted access - publisher's policy
      Although Fuzzy Preorders and Fuzzy Equivalences are well established types of fuzzy relations, they are defined in terms of properties to be fulfilled in a crisp way. In this paper we relax those requirements by making ...
    • Approximating arbitrary fuzzy subsets by extensional ones 

      Mattioli Aramburu, Gabriel; Recasens Ferrés, Jorge (2015-06-01)
      Article
      Open Access
      An interesting problem within the theory of indistinguishability operators is how to approximate an arbitrary fuzzy subset by a similar extensional one. In this paper, we aim to solve this question and provide three methods ...
    • Approximating fuzzy preorders and equivalences. A similarity based approach 

      Boixader Ibáñez, Dionís; Recasens Ferrés, Jorge (IEEE Computer Society Publications, 2010)
      Conference report
      Open Access
    • Approximating proximities by similarities 

      Garmendia Salvador, Luis; Recasens Ferrés, Jorge (Univ. Malaga, 2008)
      Conference report
      Open Access
      In this paper an algorithm to find a similarity close to a proximity or tolerance relation R is given. The obtained similarity is closer to R than its transitive closure or any transitive opening of R.