Now showing items 1-20 of 56

    • A biased-randomized learnheuristic for solving the team orienteering problem with dynamic rewards 

      Reyes-Rubiano, Lorena Silvana; Juan, Ángel Alejandro; Bayliss, C.; Panadero, J.; Faulín Fajardo, Javier Upna; Copado, P. (Elsevier, 2020)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      In this paper we discuss the team orienteering problem (TOP) with dynamic inputs. In the static version of the TOP, a fixed reward is obtained after visiting each node. Hence, given a limited fleet of vehicles and a threshold ...
    • A strategic multistage tactical two-stage stochastic optimization model for the airline fleet management problem 

      Serrano Hernández, Adrián Upna; Cadarso, Luis; Faulín Fajardo, Javier Upna (Elsevier, 2020)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      This work proposes stochastic optimization for the airline fleet management problem, considering uncertainty in the demand, operational costs, and fares. In particular, a multistage tree is proposed, compounded of strategic ...
    • AC/DC millivoltage sensor by means of ITO-coated optical fibers: towards monitoring of biosignals 

      Aginaga Etxamendi, Concepción Isabel Upna; Socorro Leránoz, Abián Bentor Upna; Fuentes Lorenzo, Omar Upna; Del Villar, Ignacio Upna; Corres Sanz, Jesús María Upna; Matías Maestro, Ignacio Upna (IEEE, 2019)   Contribución a congreso / Biltzarrerako ekarpena
      This contribution shows the monitoring of AC and DC millivoltage signals by means of lossy mode resonances generated by Indium Tin Oxide (ITO) on optical fibers. Sensors were obtained by sputtering ITO thin-films onto 25 ...
    • Hydrogen educational activities developed by APERNA: a renewable-energy student association 

      Berrueta Irigoyen, Alberto Upna; San Martín Biurrun, Idoia Upna; Samanes Pascual, Javier Upna; Pascual Miqueleiz, Julio María Upna; Barrios Rípodas, Ernesto Upna; Parra Laita, Íñigo de la Upna; Urtasun Erburu, Andoni Upna; Sanchis Gúrpide, Pablo Upna; Ursúa Rubio, Alfredo Upna (Asociación Española del Hidrógeno, 2016)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      In this paper, we present APERNA, a recently-created student association at Public University of Navarre (UPNA) with the aim of promotion of renewable energies.
    • DC capacitance reduction in three-phase photovoltaic inverters by using virtual impedance emulation 

      Urtasun Erburu, Andoni Upna; Sanchis Gúrpide, Pablo Upna; Marroyo Palomo, Luis Upna (IEEE, 2019)   Contribución a congreso / Biltzarrerako ekarpena
      DC voltage regulation in grid-connected three-phase PV inverters is a fundamental requirement. In order to reduce the influence of the PV non-linear behavior and ensure stability in the whole operating range, the input ...
    • Single feedback regulation of the AC voltage for high-power inverters under stand-alone operation 

      Erdocia Zabala, Ioseba Upna; Urtasun Erburu, Andoni Upna; Marroyo Palomo, Luis Upna (IEEE, 2019)   Contribución a congreso / Biltzarrerako ekarpena
      Energy-storage inverters under stand-alone operation must control the output voltage. However, existing methods for instantaneous voltage regulation are not suitable for high-power inverters due to their limited sampling ...
    • Comparison of fourth-harmonic and combined doubler/subharmonic mixer with integrated MMIC based local oscillator 

      Pérez Escudero, José Manuel Upna; Quemada Mayoral, Carlos Upna; Gonzalo García, Ramón Upna; Ederra Urzainqui, Íñigo Upna (IEEE, 2019)   Contribución a congreso / Biltzarrerako ekarpena
      In this paper a comparison between a fourth harmonic mixer and a combined doubler/subharmonic mixer based on Schottky diodes working at 300 GHz with MMIC Local Oscillator (LO) integrated in a single enclosing is presented. ...
    • On the requirements of the power converter for second-life lithium-ion batteries 

      Berrueta Irigoyen, Alberto Upna; San Martín Biurrun, Idoia Upna; Pascual Miqueleiz, Julio María Upna; Sanchis Gúrpide, Pablo Upna; Ursúa Rubio, Alfredo Upna (IEEE, 2019)   Contribución a congreso / Biltzarrerako ekarpena
      The use of lithium-ion batteries is increasing year after year, especially in the automotive sector. Given the high requirements of electric vehicles, their energy storage systems are discarded when they still have around ...
    • Active damping based on the capacitor voltage positive-feedback for grid-connected power converters with LCL filter 

      Samanes Pascual, Javier Upna; Gubía Villabona, Eugenio Upna (IEEE, 2019)   Contribución a congreso / Biltzarrerako ekarpena
      The capacitor voltage positive-feedback is a widely extended active damping strategy. It can effectively damp the LCL output filter resonant poles for low ratios of resonance to sampling frequencies. However, the existing ...
    • The generalized bode criterion: application to the dc voltage control of a three-phase photovoltaic grid-tied inverter 

      Lumbreras Magallón, David Upna; Barrios Rípodas, Ernesto Upna; Urtasun Erburu, Andoni Upna; Sanchis Gúrpide, Pablo Upna (IEEE, 2019)   Contribución a congreso / Biltzarrerako ekarpena
      As renewable energies are becoming more important in the electrical generation system, power electronic converters are facing new design issues related not only to their components but also to their control loops. In this ...
    • Do we still need fuzzy classifiers for Small Data in the Era of Big Data? 

      Elkano Ilintxeta, Mikel Upna; Bustince Sola, Humberto Upna; Galar Idoate, Mikel Upna (IEEE, 2019)   Contribución a congreso / Biltzarrerako ekarpena
      The Era of Big Data has forced researchers to explore new distributed solutions for building fuzzy classifiers, which often introduce approximation errors or make strong assumptions to reduce computational and memory ...
    • Super-resolution for Sentinel-2 images 

      Galar Idoate, Mikel Upna; Sesma Redín, Rubén; Ayala, C.; Aranda, C. (International Society for Photogrammetry and Remote Sensing, 2019)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      Obtaining Sentinel-2 imagery of higher spatial resolution than the native bands while ensuring that output imagery preserves the original radiometry has become a key issue since the deployment of Sentinel-2 satellites. ...
    • MIMO based decoupling strategy for grid connected power converters controlled in the synchronous reference frame 

      Samanes Pascual, Javier Upna; Gubía Villabona, Eugenio Upna; López Taberna, Jesús (IEEE, 2018)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      Power converters are frequently connected to the grid through a LCL filter, controlling its power transfer through a current control loop in the synchronous reference frame. In this reference frame, cross coupling terms ...
    • Multisampled-capacitor-voltage active damping for parallel interleaved grid connected voltage source converters with LCL filter 

      Samanes Pascual, Javier Upna; Gubía Villabona, Eugenio Upna (IEEE, 2017)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      Parallel interleaved converters for high power renewable energy systems present stability issues at the LCL resonance frequency. A multisampled measurement and filtering strategy is proposed to stabilize the system based ...
    • On the limits of the capacitor-voltage active damping for grid-connected power converters with LCL filter 

      Samanes Pascual, Javier Upna; Gubía Villabona, Eugenio Upna (IEEE, 2018)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      Active damping strategies are widely extended to avoid stability issues at the LCL filter resonant poles in grid-connected voltage source converters. The capacitor voltage derivative active damping effectively damps the ...
    • Sensorless active damping strategy for parallel interleaved voltage source power converters with LCL filter 

      Samanes Pascual, Javier Upna; Gubía Villabona, Eugenio Upna (IEEE, 2017)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      Grid-connected pulse-width modulation converters with LCL filters are widely extended as an interface for renewable energy generating systems. Those filters arise stability issues due to the filter resonance, which, must ...
    • On the influence of admissible orders in IVOVO 

      Uriz Martín, Mikel Xabier Upna; Paternain Dallo, Daniel Upna; Bustince Sola, Humberto Upna; Galar Idoate, Mikel Upna (Springer, 2019)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      It is known that when dealing with interval-valued data, there exist problems associated with the non-existence of a total order. In this work we investigate a reformulation of an interval-valued decomposition strategy for ...
    • Image feature extraction using OD-monotone functions 

      Marco Detchart, Cedric Upna; López Molina, Carlos Upna; Fernández Fernández, Francisco Javier Upna; Pagola Barrio, Miguel Upna; Bustince Sola, Humberto Upna (Springer, 2018)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      Edge detection is a basic technique used as a preliminary step for, e.g., object extraction and recognition in image processing. Many of the methods for edge detection can be fit in the breakdown structure by Bezdek, ...
    • Description and properties of curve-based monotone functions 

      Sesma Sara, Mikel Upna; Miguel Turullols, Laura de Upna; Roldán López de Hierro, Antonio F.; Špirková, Jana; Mesiar, Radko; Bustince Sola, Humberto Upna (Springer, 2019)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      Curve-based monotonicity is one of the lately introduced relaxations of monotonicity. As directional monotonicity regards monotonicity along fixed rays, which are given by real vectors, curve-based monotonicity studies the ...
    • Design of a groove gap waveguide to microstrip inline transition 

      Pérez Escudero, José Manuel Upna; Torres García, Alicia E. Upna; Gonzalo García, Ramón Upna; Ederra Urzainqui, Íñigo Upna (IEEE, 2019)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      In this paper the design of an inline transition between microstrip and groove gap waveguide operating at Wband is presented. The transition consists of two sections: a tapered microstrip line and a Chebyshev transformer. ...