Now showing items 12-31 of 75

    • Description of bow-tie nanoantennas excited by localized emitters using conformal transformation 

      Pacheco Peña, Víctor Upna; Beruete Díaz, Miguel Upna; Fernández Domínguez, Antonio I.; Luo, Yu; Navarro Cía, Miguel Upna (American Chemical Society, 2016)   Artículo / Artikulua  OpenAccess
      The unprecedented advance experienced by nano- fabrication techniques and plasmonics research over the past few years has made possible the realization of nanophotonic systems entering into the so-called strong coupling ...
    • Dispersion properties of an elliptical patch with cross shaped aperture for synchronized propagation of transverse magnetic and electric surface waves 

      Tellechea Pereda, Amagoia Upna; Ederra Urzainqui, Íñigo Upna; Gonzalo García, Ramón Upna; Iriarte Galarregui, Juan Carlos Upna (MDPI, 2018)   Artículo / Artikulua  OpenAccess
      This paper presents a novel pixel geometry for the implementation of metasurfaces requiring synchronized phase propagation of transverse magnetic (TM) and transverse electric (TE) modes. The pixel is composed by an elliptical ...
    • Equivalent and efficient optimization models for an industrial discrete event system with alternative structural configurations 

      Latorre Biel, Juan Ignacio; Jiménez Macías, Emilio; Pérez de la Parte, Mercedes (Hindawi / Wiley, 2018)   Artículo / Artikulua  OpenAccess
      Discrete event systems in applications, such as industry and supply chain,may show a very complex behavior. For this reason, their design and operation may be carried out by the application of optimization techniques for ...
    • Evaluation of deployment challenges of wireless sensor networks at signalized intersections 

      Azpilicueta Fernández de las Heras, Leyre Upna; López Iturri, Peio Upna; Aguirre Gallego, Erik Upna; Martínez Carrasco, Carlos; Astrain Escola, José Javier Upna; Villadangos Alonso, Jesús Upna; Falcone Lanas, Francisco Javier Upna (MDPI, 2016)   Artículo / Artikulua  OpenAccess
      With the growing demand of Intelligent Transportation Systems (ITS) for safer and more efficient transportation, research on and development of such vehicular communication systems have increased considerably in the last ...
    • Evolution in time of L-fuzzy context sequences 

      Alcalde, Cristina; Burusco Juandeaburre, Ana Upna; Bustince Sola, Humberto Upna; Jurío Munárriz, Aránzazu Upna; Sanz Delgado, José Antonio Upna (Elsevier, 2016)   Artículo / Artikulua  OpenAccess
      In this work, we consider a complete lattice L and we study L-fuzzy context sequences which represent the evolution in time of an L-fuzzy context. To carry out this study, in the first part of the paper, we consider n-ary ...
    • Experimental and computational study on thermoelectric generators using thermosyphons with phase change as heat exchangers 

      Araiz Vega, Miguel Upna; Martínez Echeverri, Álvaro Upna; Astrain Ulibarrena, David Upna; Aranguren Garacochea, Patricia Upna (Elsevier, 2017)   Artículo / Artikulua  OpenAccess
      An important issue in thermoelectric generators is the thermal design of the heat exchangers since it can improve their performance by increasing the heat absorbed or dissipated by the thermoelectric modules. Due to its ...
    • Experimental realization of an epsilon-near-zero graded-index metalens at terahertz frequencies 

      Pacheco Peña, Víctor Upna; Engheta, Nader; Kuznetsov, Sergei A.; Gentselev, Alexandr; Beruete Díaz, Miguel Upna (American Physical Society, 2017)   Artículo / Artikulua  OpenAccess
      The terahertz band has been historically hindered by the lack of efficient generators and detectors, but a series of recent breakthroughs have helped to effectively close the “terahertz gap.” A rapid development of terahertz ...
    • Experimental validation of a Ku-band dual circularly polarized metasurface antenna 

      Tellechea Pereda, Amagoia Upna; Caminita, Francesco; Martini, Enrica; Ederra Urzainqui, Íñigo Upna; Teniente Vallinas, Jorge Upna; Iriarte, Juan Carlos; Gonzalo, Ramón; Maci, Stefano (IEEE, 2018)   Artículo / Artikulua  OpenAccess
      The experimental validation of a Ku-band dual circularly polarized (CP) broadside-beam metasurface (MTS) antenna is presented. A radially modulated anisotropic single layer MTS has been synthesised employing sub-wavelength ...
    • Extraordinary THz transmission with a small beam spot: the leaky wave mechanism 

      Navarro Cía, Miguel Upna; Pacheco Peña, Víctor Upna; Kuznetsov, Sergei A.; Beruete Díaz, Miguel Upna (Wiley, 2018)   Artículo / Artikulua  OpenAccess
      The discovery of extraordinary optical transmission (EOT) through patterned metallic foils in the late 1990s was decisive for the development of plasmonics and cleared the path to employ small apertures for a variety of ...
    • Fabrication of Bragg gratings on the end facet of standard optical fibers by sputtering the same material 

      Ascorbe Muruzabal, Joaquín Upna; Corres Sanz, Jesús María Upna; del Villar, Ignacio Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (IEEE, 2016)   Artículo / Artikulua  OpenAccess
      A sputtering process has been applied to deposit quarter-wavelength stacks on the end facet of cleaved optical fibers by using only one sputtering target. Standard multimode optical fibers were used as substrates to fabricate ...
    • A framework for radial data comparison and its application to fingerprint analysis 

      Marco Detchart, Cedric Upna; Cerrón González, Juan Upna; Miguel Turullols, Laura de Upna; López Molina, Carlos Upna; Bustince Sola, Humberto Upna; Galar Idoate, Mikel Upna (Elsevier, 2016)   Artículo / Artikulua  OpenAccess
      This work tackles the comparison of radial data, and proposes comparison measures that are further applied to fingerprint analysis. First, we study the similarity of scalar and non-scalar radial data, elaborated on previous ...
    • Fuzzy rule-based classification systems for multi-class problems using binary decomposition strategies: on the influence of n-dimensional overlap functions in the fuzzy reasoning method 

      Elkano Ilintxeta, Mikel Upna; Galar Idoate, Mikel Upna; Sanz Delgado, José Antonio Upna; Bustince Sola, Humberto Upna (Elsevier, 2016)   Artículo / Artikulua  OpenAccess
      Multi-class classification problems appear in a broad variety of real-world problems, e.g., medicine, genomics, bioinformatics, or computer vision. In this context, decomposition strategies are useful to increase the ...
    • Giant sensitivity of optical fiber sensors by means of lossy moderesonance 

      Arregui San Martín, Francisco Javier Upna; Del Villar, Ignacio Upna; Ruiz Zamarreño, Carlos Upna; Zubiate Orzanco, Pablo Upna; Matías Maestro, Ignacio Upna (Elsevier, 2016)   Artículo / Artikulua  OpenAccess
      Here we show an optical refractometer with a giant sensitivity of 304,360 nm per refractive index unit(nm/RIU). This sensitivity corresponds to a resolution of 3.28 × 10−9RIU if a standard optical spectrumanalyzer with a ...
    • Grating lobes in higher-order correlation functions of arrays of quantum emitters: directional photon bunching 

      Liberal Olleta, Íñigo Upna; Ederra Urzainqui, Íñigo Upna; Ziolkowsky, Richard W. (MDPI, 2019)   Artículo / Artikulua  OpenAccess
      Recent advances in nanofabrication and optical manipulation techniques are making it possible to build arrays of quantum emitters with accurate control over the locations of their individual elements. In analogy with ...
    • Heat pipes thermal performance for a reversible thermoelectric cooler-heat pump for a nZEB 

      Aranguren Garacochea, Patricia Upna; Díaz de Garayo, Sergio; Martínez Echeverri, Álvaro Upna; Araiz Vega, Miguel Upna; Astrain Ulibarrena, David Upna (Elsevier, 2019)   Artículo / Artikulua
      The nZEB standards reduce the energy demand of these buildings to a minimum, obtaining this little energy from renewable resources. Taking these aspect into consideration, a thermoelectric cooler-heat pump is proposed to ...
    • High aperture efficiency wide corrugations bull’s-eye antenna working at 60 GHz 

      Beaskoetxea Gartzia, Unai Upna; Beruete Díaz, Miguel Upna (IEEE, 2017)   Artículo / Artikulua  OpenAccess
      A full metallic Bull’s-Eye (BE) antenna operating at 60 GHz is numerically and experimentally analyzed. The antenna presents wide grooves, rather than narrow ones, which support higher order resonances that lead to a large ...
    • High sensitivity humidity sensor based on cladding-etched optical fiber and lossy mode resonances 

      Ascorbe Muruzabal, Joaquín Upna; Corres Sanz, Jesús María Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (Elsevier, 2016)   Artículo / Artikulua  OpenAccess
      In this work a high sensitivity optical fiber humidity sensor (OFHS) is presented. The configuration chosen for this purpose is a cladding-etched single mode optical fiber (CE-SMF) coated with a thin film of tin oxide ...
    • Humidity sensor based on Bragg gratings developed on the end facet of an optical fiber by sputtering of one single material 

      Ascorbe Muruzabal, Joaquín Upna; Corres Sanz, Jesús María Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (MDPI, 2017)   Artículo / Artikulua  OpenAccess
      The refractive index of sputtered indium oxide nanocoatings has been altered just by changing the sputtering parameters, such as pressure. These induced changes have been exploited for the generation of a grating on the ...
    • Implementation and analysis of ISM 2.4 GHz wireless sensor network systems in judo training venues 

      López Iturri, Peio Upna; Aguirre Gallego, Erik Upna; Azpilicueta Fernández de las Heras, Leyre Upna; Astrain Escola, José Javier Upna; Villadangos Alonso, Jesús Upna; Falcone Lanas, Francisco Javier Upna (MDPI, 2016)   Artículo / Artikulua  OpenAccess
      In this work, the performance of ISM 2.4 GHz Wireless Sensor Networks (WSNs) deployed in judo training venues is analyzed. Judo is a very popular martial art, which is practiced by thousands of people not only at the ...
    • Implementation and operational analysis of an interactive intensive care unit within a smart health context 

      López Iturri, Peio Upna; Aguirre Gallego, Erik Upna; Trigo Vilaseca, Jesús Daniel; Astrain Escola, José Javier Upna; Azpilicueta Fernández de las Heras, Leyre Upna; Serrano Arriezu, Luis Javier Upna; Villadangos Alonso, Jesús Upna; Falcone Lanas, Francisco Javier Upna (MDPI, 2018)   Artículo / Artikulua  OpenAccess
      In the context of hospital management and operation, Intensive Care Units (ICU) are one of the most challenging in terms of time responsiveness and criticality, in which adequate resource management and signal processing ...