Now showing items 1-20 of 37

    • Robust multisampled capacitor voltage active damping for grid-connected power converters 

      Samanes Pascual, Javier; Urtasun Erburu, Andoni Upna; Gubía Villabona, Eugenio Upna; Petri, Alberto (Elsevier, 2019)   Artículo / Artikulua
      The derivative feedback of the capacitor voltage is one of the most extended active damping strategies, used to eliminate stability problems in grid-connected power converters with an LCL filter. This strategy is equivalent ...
    • Remote access protocols for Desktop-as-a-Service solutions 

      Magaña Lizarrondo, Eduardo Upna; Sesma Gracia, Iris; Morató Osés, Daniel Upna; Izal Azcárate, Mikel Upna (Public Library of Science, 2019)   Artículo / Artikulua  OpenAccess
      The use of remote desktop services on virtualized machines is a general trend to reduce the cost of desktop seats. Instead of assigning a physical machine with its operating system and software to each user, it is considerably ...
    • On the performance of an ENZ-based sensor using transmission line theory and effective medium approach 

      Pacheco-Peña, Víctor Upna; Beruete Díaz, Miguel Upna; Rodríguez Ulibarri, Pablo Upna; Engheta, Nader (IOP Publishing, 2019)   Artículo / Artikulua  OpenAccess
      In this paper we perform an in-depth theoretical studyofa sensing platform based on epsilon-near- zero (ENZ) metamaterials. The structure proposed for sensing is a narrow metallic waveguide channel. An equivalent circuit ...
    • Photonic nanojets with mesoscale high-index dielectric particles 

      Pacheco-Peña, Víctor Upna; Beruete Díaz, Miguel Upna (AIP Publishing, 2019)   Artículo / Artikulua  OpenAccess
      In this work, we demonstrate the ability of high-index dielectric particles immersed in air to generate photonic nanojets with extreme resolution (∼0.06λ0). Both 2D (cylindrical) and 3D (spherical) particles are analyzed, ...
    • Exact inter-discharge interval distribution of motor unit firing patterns with gamma model 

      Navallas Irujo, Javier Upna; Porta Cuéllar, Sonia; Malanda Trigueros, Armando Upna (Springer, 2019)   Artículo / Artikulua  OpenAccess
      Inter-discharge interval distribution modeling of the motor unit firing pattern plays an important role in electromyographic decomposition and the statistical analysis of firing patterns. When modeling firing patterns ...
    • Control of a photovoltaic array interfacing current-mode-controlled boost converter based on virtual impedance emulation 

      Urtasun Erburu, Andoni; Samanes Pascual, Javier; Barrios, Rípodas, Ernesto Upna; Sanchis Gúrpide, Pablo; Marroyo Palomo, Luis Upna (IEEE, 2019)   Artículo / Artikulua  OpenAccess
      Due to the nonlinear characteristics of a photovoltaic (PV) array, its regulation is highly dependent on the operating point. Focusing on a dc-dc boost converter, this paper first shows how the PV voltage and inductor ...
    • On the stability of advanced power electronic converters: the Generalized Bode Criterion 

      Lumbreras Magallón, David; Barrios, Rípodas, Ernesto Upna; Urtasun Erburu, Andoni Upna; Ursúa Rubio, Alfredo Upna; Marroyo Palomo, Luis Upna; Sanchís Gúrpide, Pablo Upna (IEEE, 2019)   Artículo / Artikulua
      A key factor in the design of power electronic converters is the development of control systems and, in particular, the determination of their stability. Due to ease of application, the Bode criteria are currently the most ...
    • Compensation of nonlocal effects induced by the extinction ratio of pump pulses in Brillouin optical time-domain analysis sensors 

      Mariñelarena Ollacarizqueta, Jon Upna; Iribas Pardo, Haritz Upna; Urricelqui Polvorinos, Javier Upna; Loayssa Lara, Alayn Upna (Optical Society of America, 2019)   Artículo / Artikulua  OpenAccess
      We demonstrate a technique to compensate the nonlocal effects that appear in Brillouin optical time-domain analysis sensors when pump pulses with limited extinction ratio are deployed. These recently discovered nonlocal ...
    • Far-field and near-field physics of extraordinary THz transmitting hole-array antennas 

      Camacho, Miguel; Boix, Rafael R.; Kuznetsov, Sergei A.; Beruete Díaz, Miguel Upna; Navarro Cía, Miguel (IEEE, 2019)   Artículo / Artikulua  OpenAccess
      Despite three decades of effort, predicting accurately extraordinary transmission through subwavelength hole arrays has proven challenging. The lack of quantitative design and modeling capability to take into account ...
    • Lossy mode resonance optical sensors based on indium-gallium-zinc oxide thin film 

      Ozcariz Celaya, Aritz Upna; Dominik, Magdalena; Smietana, Mateusz; Ruiz Zamarreño, Carlos Upna; Del Villar, Ignacio Upna; Arregui San Martín, Francisco javier Upna (Elsevier, 2019)   Artículo / Artikulua
      This work discusses an application of electrically conductive and optically transparent indium-gallium-zinc oxide (IGZO) thin films for fabrication of lossy mode resonance (LMR) based optical fiber refractometers. The films ...
    • Supercapacitors: electrical characteristics, modelling, applications and future trends 

      Berrueta Irigoyen, Alberto; Ursúa Rubio, Alfredo Upna; San Martín Biurrun, Idoia Upna; Eftekhari, Ali; Sanchís Gúrpide, Pablo Upna (IEEE, 2019)   Artículo / Artikulua  OpenAccess
      Energy storage systems are playing an increasingly important role in a variety of applications, such as electric vehicles or grid-connected systems. In this context, supercapacitors (SCs) are gaining ground due to their ...
    • General synthesis of tapered matching sections for single mode operation using the coupled-mode theory 

      Percaz Ciriza, Jon Mikel Upna; Arnedo Gil, Israel Upna; Arregui Padilla, Iván Upna; Teberio Berdún, Fernando Upna; Martín Iglesias, Petronilo; Gómez Laso, Miguel Ángel Upna; Lopetegui Beregaña, José María Upna (IEEE, 2019)   Artículo / Artikulua
      In this paper, a novel and general method to synthetize microwave waveguide tapers intended for single mode operation is proposed. The technique is based on the use of an exact series solution of the inverse scattering ...
    • Aluminum doped zinc oxide (AZO) coated optical fiber LMR refractometers—An experimental demonstration 

      Ozcariz Celaya, Aritz Upna; Piña-Azamar, Dafne A.; Ruiz Zamarreño, Carlos Upna; Dominguez, René; Arregui San Martín, Francisco Javier Upna (Elsevier, 2019)   Artículo / Artikulua
      This work presents the experimental demonstration of lossy mode resonance generation by means of aluminum doped zinc oxide thin-films. The use of such material may allow to optimize the performance of LMR-based sensors, ...
    • Robust and accurate 2D-tracking-based 3D positioning method: application to head pose estimation 

      Ariz Galilea, Mikel; Villanueva Larre, Arantxa Upna; Cabeza Laguna, Rafael Upna (Elsevier, 2019)   Artículo / Artikulua  OpenAccess
      Head pose estimation (HPE) is currently a growing research field, mainly because of the proliferation of human–computer interfaces (HCI) in the last decade. It offers a wide variety of applications, including human behavior ...
    • A water content continuous monitoring of grapevine xylem tissue using a portable low-power cost-effective FMCW radar 

      Quemada Mayoral, Carlos; García González, Cebrián; Iriarte Galarregui, Juan Carlos Upna; Marín Ederra, Diana; Gastón Beraza, Diego; Miranda Jiménez, Carlos Upna; Gonzalo García, Ramón Upna; Maestrojuán Biurrun, Itziar Upna; Santesteban García, Gonzaga Upna; Ederra Urzainqui, Íñigo Upna (IEEE, 2019)   Artículo / Artikulua
      This paper presents the real-time monitoring of a grapevine’s water content that flows up through the xylem tissue by means of a frequency-modulated continuous-wave (FMCW) radar. The application of an optimization process, ...
    • Grating lobes in higher-order correlation functions of arrays of quantum emitters: directional photon bunching 

      Liberal Olleta, Íñigo Upna; Ederra Urzainqui, Íñigo Upna; Ziolkowski, 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 ...
    • Labyrinth metasurface for biosensing applications: numerical study on the new paradigm of metageometries 

      Jáuregui López, Irati; Rodríguez Ulibarri, Pablo Upna; Kuznetsov, Sergei A.; Quemada Mayoral, Carlos; Beruete Díaz, Miguel Upna (MDPI, 2019)   Artículo / Artikulua  OpenAccess
      The use of metasurfaces operating in the terahertz regime as biosensor devices has attracted increased interest in recent years due to their enhanced sensitivity and more accurate detection capability. Typical designs are ...
    • Steering surface plasmons with a graded index dielectric medium 

      Beruete Díaz, Miguel Upna; Pacheco-Peña, Víctor Upna (IOP Publishing, 2018)   Artículo / Artikulua  OpenAccess
      The arbitrary control of surface plasmon (SP) propagation has become an intense research topic for several decades. This is due to the fact that they can be used in a variety of fields such as optical trapping, nanoantennas ...
    • 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  OpenAccess
      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 ...
    • Ransomware early detection by the analysis of file sharing traffic 

      Morató Osés, Daniel Upna; Berrueta Irigoyen, Eduardo; Magaña Lizarrondo, Eduardo Upna; Izal Azcárate, Mikel Upna (Elsevier, 2018)   Artículo / Artikulua  OpenAccess
      Crypto ransomware is a type of malware that locks access to user files by encrypting them and demands a ransom in order to obtain the decryption key. This type of malware has become a serious threat for most enterprises. ...