• openAccess   A Generalized Mazur-Ulam Theorem for Fuzzy Normed Spaces 

      Font, Juan J.; Galindo, Jorge; Macario, Sergio; Sanchis López, Manuel Hindawi Publishing Corporation (2014-06-02)
      We introduce fuzzy norm-preserving maps, which generalize the concept of fuzzy isometry. Based on the ideas from Vogt, 1973, and V¨ais¨al¨a, 2003, we provide the following generalized version of theMazur-Ulam theorem in ...
    • openAccess   Best Approximation Results for Fuzzy-Number-Valued Continuous Functions 

      Font, Juan J.; Macario, Sergio MDPI (2023-02)
      In this paper, we study the best approximation of a fixed fuzzy-number-valued continuous function to a subset of fuzzy-number-valued continuous functions. We also introduce a method to measure the distance between a ...
    • openAccess   Cálculo 

      Font, Juan J.; Hernández, Salvador; Macario, Sergio Universitat Jaume I (2009)
    • openAccess   Constructive approximation of continuous interval- valued functions 

      Font, Juan J.; Macario, Sergio Taylor & Francis (2021-11-28)
      In this paper we present a Stone-Weierstrass type result in the context of continuous interval-valued functions defined on a compact Hausdorff space. We also provide a Jackson type approximation result involving the modulus ...
    • openAccess   Endograph Metric and a Version of the Arzelà–Ascoli Theorem for Fuzzy Sets 

      Font, Juan J.; Macario, Sergio; Sanchis, Manuel MDPI (2023)
      In this paper, we provide several Arzelà–Ascoli-type results on the space of all continuous functions from a Tychonoff space X into the fuzzy sets of Rn , (FUSCB(Rn),Hend) , which are upper semi-continuous and have bounded ...
    • openAccess   Exercicis resolts i comentats de fonaments matemàtics aplicats a l' edificació 

      Macario, Sergio Publicacions de la Universitat Jaume I (2018)
    • openAccess   Gromov–Hausdorff convergence of non-Archimedean fuzzy metric spaces 

      Macario, Sergio; Sanchis López, Manuel Elsevier (2015)
      We introduce the notion of the Gromov–Hausdorff fuzzy distance between two non-Archimedean fuzzy metric spaces (in the sense of Kramosil and Michalek). Basic properties involving convergence and the fuzzy version of the ...
    • openAccess   Jackson-type approximation for fuzzy-valued functions by means of trapezoidal functions 

      Font, Juan J.; Macario, Sergio University of Sistan and Baluchestan (2023-12-15)
      In this paper, we provide new several Jackson-type approximations results for continuous fuzzy-number-valued functions which improve several previous ones. We use alternative techniques adapted from Interval Analysis which ...
    • openAccess   Mazur-Ulam type theorems for fuzzy normed spaces 

      Font, Juan J.; Galindo, Jorge; Macario, Sergio; Sanchis López, Manuel International Scientific Research Publications (ISRP) (2017-08)
      In this paper, we provide Mazur-Ulam type results for (not necessarily surjective) maps preserving equality of fuzzy distance defined between two fuzzy normed spaces. Our main goal is to study the additivity of such ...
    • openAccess   Pseudocompact group topologies with no infinite compact subsets 

      Galindo, Jorge; Macario, Sergio Elsevier (2011)
      We show that every Abelian group satisfying a mild cardinal inequality admits a pseudocompact group topology from which all countable subgroups inherit the maximal totally bounded topology (we say that such a topology satisfies ...
    • closedAccess   Uncountable products of determined groups need not be determined 

      Hernández, Salvador; Macario, Sergio; Trigos, Javier Elsevier (2008)
      If H is a dense subgroup of G, we say that H determines G if their groups of characters are topologically isomorphic when equipped with the compact open topology. If every dense subgroup of G determines G, then we say that ...