Envíos recientes

  • Study of optical fiber sensors for cryogenic temperature measurements 

    Miguel Soto, Verónica de; Leandro González, Daniel Upna; López Aldaba, Aitor Upna; Beato López, Juan Jesús; Pérez de Landazábal Berganzo, José Ignacio; Auguste, Jean-Louis; Jamier, Raphael; Roy, Philippe; López-Amo Sáinz, Manuel Upna (MDPI, 2017)   Artículo / Artikulua  OpenAccess
    In this work, the performance of five different fiber optic sensors at cryogenic temperatures has been analyzed. A photonic crystal fiber Fabry-Pérot interferometer, two Sagnac interferometers, a commercial fiber Bragg ...
  • Performance analysis of ZigBee wireless networks for AAL through hybrid ray launching and collaborative filtering 

    López Iturri, Peio Upna; Casino, Fran; Aguirre Gallego, Erik Upna; Azpilicueta Fernández de las Heras, Leyre Upna; Falcone Lanas, Francisco Javier Upna; Solanas, Agusti (Hindawi, 2016)   Artículo / Artikulua  OpenAccess
    This paper presents a novel hybrid simulation method based on the combination of an in-house developed 3D ray launching algorithm and a collaborative filtering (CF) technique, which will be used to analyze the performance ...
  • Temperature sensor using a multiwavelength erbium-doped fiber ring laser 

    Díaz Lucas, Silvia Upna; San Fabián García, Noé; Socorro Leránoz, Abián Bentor Upna; Matías Maestro, Ignacio Upna (Hindawi, 2017)   Artículo / Artikulua  OpenAccess
    A novel temperature sensor is presented based on a multiwavelength erbium-doped fiber ring laser.The laser is comprised of fiber Bragg grating reflectors as the oscillation wavelength selecting filters.The performance of ...
  • Labyrinth metasurface absorber for ultra-high-sensitivity terahertz thin film sensing 

    Jáuregui López, Irati; Rodríguez Ulibarri, Pablo Upna; Urrutia Azcona, Aitor Upna; Kuznetsov, Sergei A.; Beruete Díaz, Miguel Upna (Wiley, 2018)   Artículo / Artikulua
    In this work, a labyrinth metasurface sensor operating at the low‐frequency edge of the THz band is presented. Its intricate shape leads to a high electric field confinement on the surface of the structure, resulting in ...
  • Phase reversal technique applied to fishnet metalenses 

    Pacheco-Peña, Víctor Upna; Minin, Igor V.; Minin, Oleg V.; Beruete Díaz, Miguel Upna (Hindawi, 2018)   Artículo / Artikulua  OpenAccess
    In this work, the fishnet metamaterial is applied to several converging metalenses by combining the zoning, reference phase, and phase reversal techniques. First, the zoning and reference phase techniques are implemented ...
  • Convolution lattices 

    Miguel Turullols, Laura de Upna; Bustince Sola, Humberto Upna; De Baets, Bernard (Elsevier, 2018)   Artículo / Artikulua
    We propose two convolution operations on the set of functions between two bounded lattices and investigate the algebraic structure they constitute, in particular the lattice laws they satisfy. Each of these laws requires ...
  • Multivalued contexts associated with criteria 

    Alcalde, Cristina; Burusco Juandeaburre, Ana Upna (Taylor & Francis, 2018)   Artículo / Artikulua
    We are interested in the study of L-fuzzy contexts taking into account different criteria. These contexts arise when we want to analyze the relationship between objects and attributes from different points of view. ...
  • Linking mathematical morphology and L-fuzzy concepts 

    Alcalde, Cristina; Burusco Juandeaburre, Ana Upna; Bustince Sola, Humberto Upna; Fuentes González, Ramón Upna; Sesma Sara, Mikel Upna (World Scientific, 2017)   Artículo / Artikulua
    In this paper we study the relation between L-fuzzy morphology and L-fuzzy concepts over complete lattices. In particular, we show how the erosion and dilation operators of the former can be understood in terms of the ...
  • Luminescence-based optical sensors fabricated by means of the layer-by-layer nano-assembly technique 

    Acha Morrás, Nerea de Upna; Elosúa Aguado, César Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (MDPI, 2017)   Artículo / Artikulua  OpenAccess
    Luminescence-based sensing applications range from agriculture to biology, including medicine and environmental care, which indicates the importance of this technique as a detection tool. Luminescent optical sensors are ...
  • Sensitivity optimization with cladding-etched long period fiber gratings at the dispersion turning point 

    Del Villar, Ignacio Upna; Cruz, José Luis; Socorro Leránoz, Abián Bentor Upna; Corres Sanz, Jesús María Upna; Matías Maestro, Ignacio Upna (Optical Society of America, 2016)   Artículo / Artikulua  OpenAccess
    This work presents a refractive index sensor based on a long period fiber grating (LPFG) made in a reduced cladding fiber whose low order cladding modes have the turning point at large wavelengths. The combination of ...
  • 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 ...
  • Optimization in nanocoated D-shaped optical fiber sensors 

    Del Villar, Ignacio Upna; Zubiate Orzanco, Pablo Upna; Ruiz Zamarreño, Carlos Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (Optical Society of America, 2017)   Artículo / Artikulua  OpenAccess
    Nanocoated D-shaped optical fibers have been proven as effective sensors. Here, we show that the full width at half minimum (FWHM) of lossy mode resonance can be reduced by optimizing the nanocoating width, thickness and ...
  • Increasing the sensitivity of an optic level sensor with a wavelength and phase sensitive single-mode multimode single-mode (SMS) fiber structure 

    Fuentes, Omar; Del Villar, Ignacio Upna; Vento, José R.; Socorro Leránoz, Abián Bentor Upna; Gallego, E.E.; Corres Sanz, Jesús María Upna; Matías Maestro, Ignacio Upna (IEEE, 2017)   Artículo / Artikulua  OpenAccess
    The sensitivity of a liquid level sensor based on a single-mode-multimode-single-mode fiber structure has been increased by hydrofluoric acid etching. The etching process was analyzed and monitored both theoretical and ...
  • Nanofabrication of phase-shifted Bragg gratings on the end facet of multimode fiber towards development of optical filters and sensors 

    Gallego, E.E.; Ascorbe Muruzabal, Joaquín Upna; Del Villar, Ignacio Upna; Corres Sanz, Jesús María Upna; Matías Maestro, Ignacio Upna (Elsevier, 2018)   Artículo / Artikulua
    This work describes the process of nanofabrication of phase-shifted Bragg gratings on the end facet of a multimode optical fiber with a pulsed DC sputtering system based on a single target. Several structures have been ...
  • Optimized strain long-period fiber grating (LPFG) sensors operating at the dispersion turning point 

    Del Villar, Ignacio Upna; Fuentes, Omar; Chiavaioli, Francesco; Corres Sanz, Jesús María Upna; Matías Maestro, Ignacio Upna (IEEE, 2018)   Artículo / Artikulua  OpenAccess
    Two phenomena for enhancing the sensitivity of longperiod fiber gratings are combined toward an increase of the sensitivity to strain of this type of devices: the dispersion turning point (DTP) and the cladding diameter ...
  • Is there a frontier in sensitivity with lossy mode resonance (LMR) based refractometers? 

    Ozcariz Celaya, Aritz Upna; Ruiz Zamarreño, Carlos Upna; Zubiate Orzanco, Pablo Upna; Arregui San Martín, Francisco Javier Upna (Nature Publishing Group, 2017)   Artículo / Artikulua  OpenAccess
    A tin dioxide thin layer has been studied in order to improve the sensitivity of lossy mode resonances (LMR) based sensors. The effects of the thin film thickness and the polarization of light in a SnO2 coated D-shaped ...
  • 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
    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 ...
  • Application of two different methods for extending lattice-valued restricted equivalence functions used for constructing similarity measures on L-fuzzy sets 

    Palmeira, Eduardo S.; Bedregal, Benjamin; Bustince Sola, Humberto Upna; Paternain Dallo, Daniel Upna; Miguel Turullols, Laura de Upna (Elsevier, 2018)   Artículo / Artikulua
    Based on previous investigations, we have proposed two different methods to extend lattice-valued fuzzy connectives (t-norms, t-conorms, negations and implications) and other related operators, considering a generalized ...
  • Ku band low profile asymmetric Bull’s-Eye antenna with reduced side lobes and monopole feeding 

    Beaskoetxea Gartzia, Unai Upna; Torres García, Alicia E. Upna; Beruete Díaz, Miguel Upna (IEEE, 2018)   Artículo / Artikulua  OpenAccess
    In this paper, a linearly polarized low profile and asymmetric Bull’s-Eye leaky wave antenna fed by a monopole operating at 13 GHz is presented. Broadside radiation from the monopole is achieved by surrounding it with an ...
  • Binary relations coming from solutions of functional equations: orderings and fuzzy subsets 

    Campión Arrastia, María Jesús Upna; Miguel Turullols, Laura de Upna; García Catalán, Olga Raquel Upna; Induráin Eraso, Esteban Upna; Abrísqueta Usaola, Francisco Javier Upna (World Scientific Publishing Company, 2017)   Artículo / Artikulua
    We analyze the main properties of binary relations, defined o n a nonempty set, that arise in a natural way when dealing with real-valued functions that satisfy certain classical functional equations on two variables. We ...

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