• On a modifcation of Olver's method: a special case 

      Ferreira, Chelo; López García, José Luis; Pérez Sinusía, Ester (Springer US, 2016)   Artículo / Artikulua  OpenAccess
      We consider the asymptotic method designed by Olver (Asymptotics and special functions. Academic Press, New York, 1974) for linear differential equations of the second order containing a large (asymptotic) parameter : xm ...
    • Orthogonal basis with a conicoid first mode for shape specification of optical surfaces 

      Ferreira, Chelo; López García, José Luis; Navarro, Rafael; Pérez Sinusía, Ester (Optical Society of America, 2016)   Artículo / Artikulua  OpenAccess
      A rigorous and powerful theoretical framework is proposed to obtain systems of orthogonal functions (or shape modes) to represent optical surfaces. The method is general so it can be applied to different initial shapes and ...
    • The Pearcey integral in the highly oscillatory region 

      López García, José Luis; Pagola Martínez, Pedro Jesús (Elsevier, 2016)   Artículo / Artikulua  OpenAccess
      We consider the Pearcey integral P(x, y) for large values of |y| and bounded values of |x|. The integrand of the Pearcey integral oscillates wildly in this region and the asymptotic saddle point analysis is complicated. ...
    • Characterization of wireless channel impact on wireless sensor network performance in public transportation buses 

      Azpilicueta Fernández de las Heras, Leyre Upna; López Iturri, Peio Upna; Aguirre Gallego, Erik Upna; Astrain Escola, José Javier Upna; Villadangos Alonso, Jesús Upna; Zubiri Segura, Cristóbal; Falcone Lanas, Francisco Javier Upna (IEEE, 2015)   Artículo / Artikulua  OpenAccess
      Wireless communications systems are growing rapidly during the last two decades and they are gaining a significant role for multiple communication tasks within public transportation buses. In this work, the impact of ...
    • Holographic acoustic elements for manipulation of levitated objects 

      Marzo Pérez, Asier Upna; Seah, Sue Ann; Drinkwater, Bruce W.; Sahoo, Deepak Ranjan; Long, Benjamin; Subramanian, Sriram (Nature Publishing Group, 2015)   Artículo / Artikulua  OpenAccess
      Sound can levitate objects of different sizes and materials through air, water and tissue. This allows us to manipulate cells, liquids, compounds or living things without touching or contaminating them. However, acoustic ...
    • Analysis of wireless sensor network topology and estimation of optimal network deployment by deterministic radio channel characterization 

      Aguirre Gallego, Erik Upna; López Iturri, Peio Upna; Azpilicueta Fernández de las Heras, Leyre Upna; Astrain Escola, José Javier Upna; Villadangos Alonso, Jesús Upna; Falcone Lanas, Francisco Javier Upna (MDPI, 2015)   Artículo / Artikulua  OpenAccess
      One of the main challenges in the implementation and design of context-aware scenarios is the adequate deployment strategy for Wireless Sensor Networks (WSNs), mainly due to the strong dependence of the radiofrequency ...
    • Zernike-like systems in polygons and polygonal facets 

      Ferreira, Chelo; López García, José Luis; Navarro, Rafael; Pérez Sinusía, Ester (Optical Society of America, 2015)   Artículo / Artikulua  OpenAccess
      Zernike polynomials are commonly used to represent the wavefront phase on circular optical apertures, since they form a complete and orthonormal basis on the unit disk. In [Diaz et all, 2014] we introduced a new Zernike ...
    • Convergent and asymptotic expansions of the Pearcey integral 

      López García, José Luis; Pagola Martínez, Pedro Jesús (Elsevier, 2015)   Artículo / Artikulua  OpenAccess
      We consider the Pearcey integral P(x; y) for large values of |x|, x, y ∈ C. We can find in the literature several convergent or asymptotic expansions in terms of elementary and special functions, with different levels of ...
    • Optimized strong stability preserving IMEX Runge-Kutta methods 

      Higueras Sanz, Inmaculada Upna; Happenhofer, Natalie; Koch, Othmar; Kupka, Friedrich (2014)   Artículo / Artikulua  OpenAccess
      We construct and analyze robust strong stability preserving IMplicit-EXplicit Runge-Kutta (IMEX RK) methods for models of flow with diffusion as they appear in astrophysics and in many other fields where equations with ...
    • Radio characterization for ISM 2.4 GHz wireless sensor networks for judo monitoring applications 

      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, 2014)   Artículo / Artikulua  OpenAccess
      In this work, the characterization of the radio channel for ISM 2.4GHz Wireless Sensor Networks (WSNs) for judo applications is presented. The environments where judo activity is held are usually complex indoor scenarios ...
    • Generalization of Zernike polynomials for regular portions of circles and ellipses 

      Navarro, Rafael; López García, José Luis; Díaz, José A.; Pérez Sinusía, Ester (Optical Society of America, 2014)   Artículo / Artikulua  OpenAccess
      Zernike polynomials are commonly used to represent the wavefront phase on circular optical apertures, since they form a complete and orthonormal basis on the unit circle. Here, we present a generalization of this Zernike ...
    • Analysis of radio wave propagation for ISM 2.4 GHz wireless sensor networks in inhomogeneous vegetation environments 

      Azpilicueta Fernández de las Heras, Leyre Upna; López Iturri, Peio Upna; Aguirre Gallego, Erik Upna; Mateo Zozaya, Ignacio; Astrain Escola, José Javier Upna; Villadangos Alonso, Jesús Upna; Falcone Lanas, Francisco Javier Upna (MDPI, 2014)   Artículo / Artikulua  OpenAccess
      The use of wireless networks has experienced exponential growth due to the improvements in terms of battery life and low consumption of the devices. However, it is compulsory to conduct previous radio propagation analysis ...
    • IVAN: Intelligent van for the distribution of pharmaceutical drugs 

      Moreno, Asier; Angulo Martínez, Ignacio; Perallos Ruiz, Asier; Landaluce, Hugo; García Zuazola, Ignacio Julio; Azpilicueta Fernández de las Heras, Leyre Upna; Astrain Escola, José Javier Upna; Falcone Lanas, Francisco Javier Upna; Villadangos Alonso, Jesús Upna (MDPI, 2012)   Artículo / Artikulua  OpenAccess
      This paper describes a telematic system based on an intelligent van which is capable of tracing pharmaceutical drugs over delivery routes from a warehouse to pharmacies, without altering carriers' daily conventional tasks. ...
    • Hill problem analytical theory to the order four: application to the computation of frozen orbits around planetary satellites 

      Lara, Martín; Palacián Subiela, Jesús Francisco Upna (Hindawi Publishing Corporation, 2009)   Artículo / Artikulua  OpenAccess
      Frozen orbits of the Hill problem are determined in the double-averaged problem, where short and long-period terms are removed by means of Lie transforms. Due to the perturbation method we use, the initial conditions ...
    • Formulas for the amplitude of the van der Pol limit cycle through the homotopy analysis method 

      López García, José Luis; Abbasbandy, S.; López Ruiz, R. (Hindawi / Wiley, 2009)   Artículo / Artikulua  OpenAccess
      The limit cycle of the van der Pol oscillator, x¨+ε(x2−1)x˙+x=0, is studied in the plane (x,x˙) by applying the homotopy analysis method. A recursive set of formulas that approximate the amplitude and form of this limit ...
    • A mixed-FEM and BEM coupling for the approximation of the scattering of thermal waves in locally non-homogeneous media 

      Rapún Araiz, María Luisa; Sayas, Francisco Javier (EDP Sciences, 2006)   Artículo / Artikulua  OpenAccess
      This paper proposes and analyzes a BEM-FEM scheme to approximate a time-harmonic diffusion problem in the plane with non-constant coefficients in a bounded area. The model is set as a Helmholtz transmission problem with ...