Now showing items 1-20 of 21

    • Effects of a soft-core coulomb potential on the dynamics of a hydrogen atom near a metal surface 

      Iñarrea, Manuel; Lanchares, Víctor; Palacián Subiela, Jesús Francisco Upna; Pascual, Ana Isabel; Salas, José Pablo; Yanguas Sayas, Patricia Upna (Elsevier, 2019)   Artículo / Artikulua
      The goal of this paper is to investigate the effects that the replacement of the Coulomb potential by a soft-core Coulomb potential produces in the classical dynamics of a perturbed Rydberg hydrogen atom. As example, we ...
    • 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 ...
    • Strong stability preserving properties of composition Runge-Kutta schemes 

      Higueras Sanz, Inmaculada Upna; Roldán Marrodán, Teodoro Upna (Springer, 2019)   Artículo / Artikulua
      In this paper Strong Stability Preserving (SSP) properties of Runge Kutta methods obtained by com- posing k different schemes with different step sizes are studied. The SSP coefficient of the composition method is obtained ...
    • Efficient SSP low-storage Runge-Kutta methods 

      Roldán Marrodán, Teodoro Upna; Higueras Sanz, Inmaculada Upna (2019)   Artículo / Artikulua  OpenAccess
      In this paper we study the efficiency of Strong Stability Preserving (SSP) Runge-Kutta methods that can be implemented with a low number of registers using their Shu-Osher representation. SSP methods have been studied ...
    • Corrigendum to “Oscillatory motions in restricted N-body problems” [J. Differential Equations 265 (2018) 779–803] 

      Alvarez-Ramírez, Martha; García, Antonio Upna; Palacián Subiela, Jesús Francisco Upna; Yanguas Sayas, Patricia Upna (Elsevier, 2019)   Artículo / Artikulua
      At the beginning of paper [1] there is an error that spreads along the rest of the work and the conclusions are not correct in their present form. Precisely, in Section 2, page 783, there is a contradiction related to the ...
    • 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 (IEEE, 2019)   Artículo / Artikulua
      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 ...
    • 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 ...
    • Conditional quasi-greedy bases in non-superreflexive Banach spaces 

      Albiac Alesanco, Fernando José Upna; Ansorena, José L.; Wojtaszczyk, Przemyslaw (Springer, 2019)   Artículo / Artikulua  OpenAccess
      For a conditional quasi-greedy basis B in a Banach space, the associated conditionality constants km[B] verify the estimate km[B]=O(logm). Answering a question raised by Temlyakov, Yang, and Ye, several authors have studied ...
    • Effect of thermal stress on tissue ultrastructure and metabolite profiles during initiation of Radiata pine somatic embryogenesis 

      Castander Olarieta, Ander; Montalbán, Itziar A.; Oliveira, Eliana de Medeiros; Dell'Aversana, Emilia; D'Amelia, Luisa; Carillo, Petronia; Steiner, Neusa; Fraga, Hugo Pacheco de Freitas; Guerra, Miguel Pedro; Goicoa Mangado, Tomás Upna; Ugarte Martínez, María Dolores Upna (Frontiers Media, 2019)   Artículo / Artikulua  OpenAccess
      Climate change will inevitably lead to environmental variations, thus plant drought tolerance will be a determinant factor in the success of plantations and natural forestry recovery. Some metabolites, such as soluble ...
    • 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 ...
    • 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 ...
    • Tailoring the structural and magnetic properties of Co-Zn nanosized ferrites for hyperthermia applications 

      Gómez Polo, Cristina; Recarte Callado, Vicente Upna; Cervera Gabalda, Laura María; Beato López, Juan Jesús; López García, Javier; Rodríguez Velamazán, José Alberto; Ugarte Martínez, María Dolores Upna; Mendonça, E. C.; Duque, J. G. S. (Elsevier, 2018)   Artículo / Artikulua
      A comparative study of the magnetic properties (magnetic moment, magnetocrystalline anisotropy) and hyperthermia response in Co-Zn spinel nanoparticles is presented. The CoxZn1-xFe2O4 nanoparticles (x = 1, 0.5, 0.4, 0.3, ...
    • Automatic contactless injection, transportation, merging, and ejection of droplets with a multifocal point acoustic levitator 

      Andrade, Marco Aurélio Brizzotti; Camargo, Thales S. A.; Marzo Pérez, Asier (AIP Publishing, 2018)   Artículo / Artikulua
      We present an acoustic levitation system that automatically injects, transports, merges and ejects liquid droplets in mid-air. The system consists of a phased array operating at 40 kHz on top of a plane reflector. The phase ...
    • Temperature and water availability during maturation affect the cytokinins and auxins profile of radiata pine somatic embryos 

      Moncaleán, Paloma; García Mendiguren, Olatz; Novák, Ondrej; Strnad,Miroslav; Goicoa Mangado, Tomás Upna; Ugarte Martínez, María Dolores Upna; Montalbán, Itziar A. (Frontiers Media, 2018)   Artículo / Artikulua  OpenAccess
      Somatic embryogenesis (SE) provides us a potent biotechnological tool to manipulate the physical and chemical conditions (water availability) along the process and to study their effect in the final success in terms of ...
    • Convergent expansions of the confluent hypergeometric functions in terms of elementary functions 

      Bujanda Cirauqui, Blanca Upna; López García, José Luis; Pagola Martínez, Pedro Jesús (American Mathematical Society, 2018)   Artículo / Artikulua  OpenAccess
      We consider the confluent hypergeometric function M(a, b; z) for z ∈ C and Rb >Ra > 0, and the confluent hypergeometric function U(a, b; z) for b ∈ C, Ra > 0, and Rz > 0. We derive two convergent expansions of M(a, b; z); ...
    • Dynamics in the charged restricted circular three-body problem 

      Palacián Subiela, Jesús Francisco Upna; Vidal Díaz, Claudio; Vidarte, Jhon; Yanguas Sayas, Patricia Upna (Springer US, 2018)   Artículo / Artikulua  OpenAccess
      The existence and stability of periodic solutions for different types of perturbations associated to the Charged Restricted Circular Three Body Problem (shortly, CHRCTBP) is tackled using reduction and averaging theories ...
    • 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; 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) ...
    • Características y métodos estadísticos empleados en los artículos originales publicados en las revistas de salud pública en España 

      Martínez Baz, Iván; Delfrade Osinaga, J. Upna; Etxeberria Andueza, Jaione Upna (Gobierno de Navarra, 2018)   Artículo / Artikulua  OpenAccess
      Background. To describe the characteristics and statistical methods used in the original articles published in Gaceta Sanitaria, Revista Española de Salud Pública y Anales del Sistema Sanitario de Navarra, the Spanish ...
    • 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 ...
    • Geometrical aggregation of finite fuzzy sets 

      Campión Arrastia, María Jesús Upna; García Catalán, Olga Raquel Upna; Indurain Eraso, Esteban; 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 ...