Now showing items 17-36 of 42

    • Geometric multigrid methods for Darcy–Forchheimer flow in fractured porous media 

      Arrarás Ventura, Andrés; Gaspar, F. J.; Portero Egea, Laura Upna; Rodrigo, C. (Elsevier, 2019)   Artículo / Artikulua
      In this paper, we present a monolithic multigrid method for the efficient solution of flow problems in fractured porous media. Specifically, we consider a mixed-dimensional model which couples Darcy flow in the porous ...
    • 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 Upna; 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 ...
    • Hyperspectral imaging to assess the presence of powdery mildew (Erysiphe necator) in cv. Carignan Noir grapevine bunches 

      Pérez Roncal, Claudia; López Maestresalas, Ainara Upna; López Molina, Carlos Upna; Jarén Ceballos, Carmen Upna; Urrestarazu Vidart, Jorge Upna; Santesteban García, Gonzaga Upna; Arazuri Garín, Silvia Upna (MDPI, 2020)   Artículo / Artikulua  OpenAccess
      Powdery mildew is a worldwide major fungal disease for grapevine, which adversely affects both crop yield and produce quality. Disease identification is based on visible signs of a pathogen once the plant has already been ...
    • Impact of successful treatment with directacting antiviral agents on health-related quality of life in chronic hepatitis C patients 

      Juanbeltz Zurbano, Regina; Martínez Baz, Iván Upna; San Miguel Elcano, Ramón; Goñi Esarte, Silvia; Cabasés Hita, Juan Manuel Upna; Castilla Catalán, Jesús (Public Library of Science, 2018)   Artículo / Artikulua  OpenAccess
      Background. Direct-acting antivirals (DAA) have demonstrated high efficacy to achieve sustained virological response (SVR) in chronic hepatitis C patients. We aim to assess the change in healthrelated quality of life (HRQoL) ...
    • Improving the performance of fuzzy rule-based classification systems based on a nonaveraging generalization of CC-integrals named C-F1F2-integrals 

      Lucca, Giancarlo; Pereira Dimuro, Graçaliz Upna; Fernández Fernández, Francisco Javier Upna; Bustince Sola, Humberto Upna; Bedregal, Benjamin; Sanz Delgado, José Antonio Upna (IEEE, 2019)   Artículo / Artikulua  OpenAccess
      A key component of fuzzy rule-based classification systems (FRBCS) is the fuzzy reasoning method (FRM) since it infers the class predicted for new examples. A crucial stage in any FRM is the way in which the information ...
    • The interval-valued Choquet integral based on admissible permutations 

      Paternain Dallo, Daniel Upna; Miguel Turullols, Laura de Upna; Ochoa Lezaun, Gustavo Upna; Lizasoain Iriso, María Inmaculada Upna; Mesiar, Radko; Bustince Sola, Humberto Upna (IEEE, 2018)   Artículo / Artikulua
      Aggregation or fusion of interval data is not a trivial task, since the necessity of arranging data arises in many aggregation functions, such as OWA operators or the Choquet integral. Some arranging procedures have been ...
    • The law of O-conditionality for fuzzy implications constructed from overlap and grouping functions 

      Pereira Dimuro, Graçaliz Upna; Bedregal, Benjamin; Fernández Fernández, Francisco Javier Upna; Sesma Sara, Mikel Upna; Pintor Borobia, Jesús María Upna; Bustince Sola, Humberto Upna (Elsevier, 2019)   Artículo / Artikulua
      Overlap and grouping functions are special kinds of non necessarily associative aggregation operators proposed for many applications, mainly when the associativity property is not strongly required. The classes of overlap ...
    • Mixture functions and their monotonicity 

      Špirková, Jana; Beliakov, Gleb Upna; Bustince Sola, Humberto Upna; Fernández Fernández, Francisco Javier Upna (Elsevier, 2019)   Artículo / Artikulua
      We consider mixture functions, which are a type of weighted averages for which the corresponding weights are calculated by means of appropriate continuous functions of their inputs. In general, these mixture function need ...
    • Multimodal fuzzy fusion for enhancing the motor-imagery-based brain computer interface 

      Ko, Li-Wei; Lu, Yi-Chen; Bustince Sola, Humberto Upna; Chang, Yu-Cheng; Chang, Yang; Fernández Fernández, Francisco Javier Upna; Wang, Yu-Kai; Sanz Delgado, José Antonio Upna; Pereira Dimuro, Graçaliz Upna; Lin, Chin-Teng (IEEE, 2019)   Artículo / Artikulua  OpenAccess
      Brain–computer interface technologies, such as steady-state visually evoked potential, P300, and motor imagery are methods of communication between the human brain and the external devices. Motor imagery–based brain–computer ...
    • Multipoint flux mixed finite element methods for slightly compressible flow in porous media 

      Arrarás Ventura, Andrés; Portero Egea, Laura Upna (Elsevier, 2019)   Artículo / Artikulua
      In this paper, we consider multipoint flux mixed finite element discretizations for slightly compressible Darcy flow in porous media. The methods are formulated on general meshes composed of triangles, quadrilaterals, ...
    • Normalization through invariants in n-dimensional Kepler problems 

      Meyer, Kenneth Ray; Palacián Subiela, Jesús Francisco Upna; Yanguas Sayas, Patricia Upna (Pleiades Publishing, 2018)   Artículo / Artikulua  OpenAccess
      We present a procedure for the normalization of perturbed Keplerian problems in n dimensions based on Moser regularization of the Kepler problem and the invariants associated to the reduction process. The approach allows ...
    • The null space of fuzzy inclusion measures 

      Couso, Inés; Bustince Sola, Humberto Upna; Fernández Fernández, Francisco Javier Upna; Sánchez, Luciano (IEEE, 2019)   Artículo / Artikulua
      Some formal relationships between the different axiomatic definitions of inclusion measure are analysed. In particular, the links between the different proposals about the null-space (the collection of pairs associated ...
    • On a particular class of Meijer's G functions appearing in fractional calculus 

      Karp, D. B.; López García, José Luis Upna (Academic Publications, 2018)   Artículo / Artikulua  OpenAccess
      In this paper we investigate the Meijer G-function G p+1,p+1 p,1 which, for certain parameter values, represents the Riemann-Liouville fractional integral of the Meijer-Nørlund function G p,p. p,0 The properties of this ...
    • On co-orbital quasi-periodic motion in the three-body problem 

      Cors, Josep Maria; Palacián Subiela, Jesús Francisco Upna; Yanguas Sayas, Patricia Upna (Society for Industrial and Applied Mathematics (SIAM), 2019)   Artículo / Artikulua  OpenAccess
      Within the framework of the planar three-body problem we establish the existence of quasi-periodic motions and KAM 4-tori related to the co-orbital motion of two small moons about a large planet where the moons move in ...
    • On fixed point theory in partially ordered sets and an application to asymptotic complexity of algorithms 

      Estevan Muguerza, Asier Upna; Miñana, Juan José; Valero, Óscar (Springer, 2019)   Artículo / Artikulua
      The celebrated Kleene fixed point theorem is crucial in the mathematical modelling of recursive specifications in Denotational Semantics. In this paper we discuss whether the hypothesis of the aforementioned result can be ...
    • Online relative risks/rates estimation in spatial and spatio-temporal disease mapping 

      Adin Urtasun, Aritz Upna; Goicoa Mangado, Tomás Upna; Ugarte Martínez, María Dolores Upna (Elsevier, 2019)   Artículo / Artikulua
      Background and objective: Spatial and spatio-temporal analyses of count data are crucial in epidemiology and other fields to unveil spatial and spatio-temporal patterns of incidence and/or mortality risks. However, fitting ...
    • Orness measurements for lattice m-dimensional interval-valued OWA operators 

      Miguel Turullols, Laura de Upna; Paternain Dallo, Daniel Upna; Lizasoain Iriso, María Inmaculada Upna; Ochoa Lezaun, Gustavo Upna; Bustince Sola, Humberto Upna (Elsevier, 2018)   Artículo / Artikulua
      Ordered weighted average (OWA) operators are commonly used to aggregate information in multiple situations, such as decision making problems or image processing tasks. The great variety of weights that can be chosen to ...
    • Periodic solutions, KAM tori and bifurcations in a cosmology-inspired potential 

      Palacián Subiela, Jesús Francisco Upna; Vidal Díaz, Claudio; Vidarte, Jhon; Yanguas Sayas, Patricia Upna (IOP Publishing, 2019)   Artículo / Artikulua
      A family of perturbed Hamiltonians H = 1/2 (x^2 + X^2) − 1/2 (y^2 + Y^2)+1/2 (z^2 + Z^2) + 2[ (x^4 + y^4 + z^4) + (x^2 y^2 + x^2 z^2 + y^2 z^2)] in 1: −1:1 resonance depending on two real parameters is considered. We ...
    • Short- and mid-term evaluation of the use of electric vehicles in urban freight transport collaborative networks: a case study 

      Muñoz Villamizar, Andrés; Quintero Araújo, Carlos L.; Montoya Torres, Jairo R.; Faulín Fajardo, Javier Upna (Taylor & Francis, 2019)   Artículo / Artikulua  OpenAccess
      Despite its negative impacts, freight transportation is a primary component of all supply chains. Decision makers have considered diverse strategies, such as Horizontal Collaboration (HC) and the usage of alternative types ...
    • Strengthened ordered directionally monotone functions. Links between the different notions of monotonicity 

      Sesma Sara, Mikel Upna; Lafuente López, Julio Upna; Roldán, Antonio; Mesiar, Radko; Bustince Sola, Humberto Upna (Elsevier, 2019)   Artículo / Artikulua
      In this work, we propose a new notion of monotonicity: strengthened ordered directional monotonicity. This generalization of monotonicity is based on directional monotonicity and ordered directional monotonicity, two recent ...