Now showing items 1-4 of 4

    • Binary relations coming from solutions of functional equations: orderings and fuzzy subsets 

      Campión Arrastia, María Jesús Upna; Miguel Turullols, Laura de Upna; García Catalán, Olga Raquel Upna; Induráin Eraso, Esteban Upna; Abrísqueta Usaola, Francisco Javier Upna (World Scientific Publishing Company, 2017)   Artículo / Artikulua  OpenAccess
      We analyze the main properties of binary relations, defined on a nonempty set, that arise in a natural way when dealing with real-valued functions that satisfy certain classical functional equations on two variables. We ...
    • Geometrical aggregation of finite fuzzy sets 

      Campión Arrastia, María Jesús Upna; García Catalán, Olga Raquel Upna; Induráin Eraso, Esteban Upna; Lizasoain Iriso, María Inmaculada Upna; Raventós Pujol, Armajac; Valero, Óscar (Elsevier, 2018)   Artículo / Artikulua
      A fuzzy set on a finite universe can be interpreted as a vector in a unit cube. This gives rise to a huge variety of approaches in order to aggregate finite fuzzy sets or to modify a given one. We analyze several geometrical ...
    • New trends on the numerical representability of semiordered structures 

      Abrísqueta Usaola, Francisco Javier Upna; Campión Arrastia, María Jesús Upna; García Catalán, Olga Raquel Upna; Miguel Velasco, Juan Ramón de Upna; Estevan Muguerza, Asier Upna; Induráin Eraso, Esteban Upna; Zudaire Sarobe, Margarita Upna; Agud, L.; Candeal, Juan Carlos; Díaz, S.; Martinetti, D.; Montes, S.; Gutiérrez García, J. (EUSFLAT, 2012)   Artículo / Artikulua  OpenAccess
      We introduce a survey, including the historical background, on di erent techniques that have recently been issued in the search for a characterization of the representability of semiordered structures, in the sense of ...
    • Weightable quasi-metrics related to fuzzy sets 

      Campión Arrastia, María Jesús Upna; García Catalán, Olga Raquel Upna; Induráin Eraso, Esteban Upna; Valero, Óscar (Hacettepe University (Turquía), 2018)   Artículo / Artikulua  OpenAccess
      We show that the definition of a fuzzy set is directly related to the existence of a weightable quasi-metric on a universe. This relationship is also explored in terms of functional equations coming either from the membership ...