Carmona-Cervelló, N. (Neus)

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    Aging of ECG characteristics over a five year period
    (IEEE, 2013) Carmona-Cervelló, N. (Neus); Elorza-Barbajero, J. (Jorge); Palacios-Estremera, M.C. (Maria Carmen); Bragard, J. (Jean); Rua-Seoane, J.C. (Juan Carlos); Saenz-de-Pipaon, E. (Edurne)
    The aim of this work was to find evidence of aging of ECG indicators in a population of young adults (52 subjects of age 19 ± 0.6 in 2002). For this purpose, an application which analyzes ECG signals was designed and implemented. The data consist in four different series for each subject of the studied population. Two ECG signals of 5 minute duration (one at rest and one after a mild effort) were taken in 2002 and the exact same procedure was repeated for each subject five years later in 2007. All these electrocardiographic signals were examined by computational techniques in order to extract the RR and QT intervals and the energy content of the T-wave. Next, we have compared all the data using first return maps and measured the data dispersion by evaluating the covariance ellipses. Relations between each of the four data series were studied. The analysis also included the gender and the categorical aspect “practicing sport”.
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    Some illustrative examples of permutability of fuzzy operators and fuzzy relations
    (Universidad de Zaragoza, 2014) Carmona-Cervelló, N. (Neus); Recasens-Ferres, J. (Jorge); Elorza-Barbajero, J. (Jorge); Bragard, J. (Jean)
    Composition of fuzzy operators often appears and it is natural to ask when the order of composition does not change the result. In previous papers, we characterized permutability in the case of fuzzy consequence operators and fuzzy interior operators. We also showed the connection between the permutability of the fuzzy relations and the permutability of their induced fuzzy operators. In this work we present some examples of permutability and non permutability of fuzzy operators and fuzzy relations in order to illustrate these results.
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    Permutability of fuzzy consequence and interior operators and their connection with fuzzy relations
    (Servicio de Publicaciones de la Universidad de Navarra, 2014) Carmona-Cervelló, N. (Neus); Elorza-Barbajero, J. (Jorge)
    This work is structured as follows. In Chapter 1 we brief y introduce some background and we recall the main definitions and results that will be needed. In Chapter 2 we collect several results that show connections between fuzzy relations and fuzzy operators. We also extend some of the known definitions to a more general ones. Chapter 3 is devoted to the analysis of permutability. We start analyzing certain cases of fuzzy relations and fuzzy operators. In particular, fuzzy preorders and indistinguishabilities and fuzzy consequence and interior operators. Then, we relate permutability of fuzzy relations with permutability of the operators that they induce using the different processes defined in Chapter 2. We focus in the cases of fuzzy operators induced by fuzzy preorders and similarities. Finally, we present the conclusions and the possible future work.