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  • Prediction of main potato compounds by NIRS 

    López-Maestresalas, Ainara Upna; Pérez Roncal, Claudia Upna; Tierno, Roberto Upna; Arazuri Garín, Silvia Upna; Ruiz de Galarreta, José Ignacio Upna; Jarén Ceballos, Carmen Upna (AIDIC, 2017)   Artículo / Artikulua  OpenAccess
    Potato (Solanum tuberosum, L) compounds are generally determined by analytical methods including gasliquid chromatography (GLC), HPLC and UV-VIS spectrophotometry. These methods require a lot of time and are destructive. ...
  • A multi-year analysis of traffic accidents involving agricultural tractors 

    Arnal Atarés, Pedro Upna; López-Maestresalas, Ainara Upna; Arazuri Garín, Silvia Upna; Mangado, Jesús Upna; Jarén Ceballos, Carmen Upna (AIDIC, 2017)   Artículo / Artikulua  OpenAccess
    The agricultural sector in Spain is responsible for a high rate of accidents every year, and many of them are traffic accidents. Tractors are a relatively rare sight on roads, meaning that the incidence of accidents involving ...
  • Convergent and asymptotic methods for second-order difference equations with a large parameter 

    Ferreira, Chelo; López García, José Luis; Pérez Sinusía, Ester (Springer, 2018)   Artículo / Artikulua
    We consider the second-order linear difference equation y(n+2)−2ay(n+1)−Λ2y(n)=g(n)y(n)+f(n)y(n+1) , where Λ is a large complex parameter, a≥0 and g and f are sequences of complex numbers. Two methods are proposed to find ...
  • The asymptotic expansion of the swallowtail integral in the highly oscillatory region 

    Ferreira, Chelo; López García, José Luis; Pérez Sinusía, Ester (Elsevier, 2018)   Artículo / Artikulua
    The mathematical models of many short wavelength phenomena, specially wave propagation and optical diffraction, contain, as a basic ingredient, oscillatory integrals with several nearly coincident stationary phase or saddle ...
  • Uniform convergent expansions of the Gauss hypergeometric function in terms of elementary functions 

    Ferreira, Chelo; López García, José Luis; Pérez Sinusía, Ester (Taylor & Francis, 2018)   Artículo / Artikulua
    We consider the hypergeometric function 2F1(a, b; c; z) for z ∈ C \ [1,∞). For Ra ≥ 0, we derive a convergent expansion of 2F1(a, b; c; z) in terms of the function (1 − z)−a and of rational functions of z that is uniformly ...
  • Uniform representation of the incomplete beta function in terms of elementary functions 

    Ferreira, Chelo; López García, José Luis; Pérez Sinusía, Ester (Kent State UniversityJohann Radon Institute (RICAM), 2018)   Artículo / Artikulua  OpenAccess
    We consider the incomplete beta function Bz(a, b) in the maximum domain of analyticity of its three variables: a, b, z ∈ C, −a /∈ N, z /∈ [1, ∞). For <b ≤ 1 we derive a convergent expansion of z−aBz(a, b) in terms of the ...
  • Asymptotic and convergent expansions for solutions of third-order linear differential equations with a large parameter 

    Ferreira, Chelo; López García, José Luis; Pérez Sinusía, Ester (Shanghai Normal UniversityWilmington Scientific Publisher, 2018)   Artículo / Artikulua  OpenAccess
    In previous papers [6–8,10], we derived convergent and asymptotic expansions of solutions of second order linear differential equations with a large parameter. In those papers we generalized and developed special cases not ...
  • Convergent expansions of the confluent hypergeometric functions in terms of elementary functions 

    Bujanda Cirauqui, Blanca Upna; López García, José Luis; Pagola Martínez, Pedro Jesús (American Mathematical Society, 2018)   Artículo / Artikulua  OpenAccess
    We consider the confluent hypergeometric function M(a, b; z) for z ∈ C and Rb >Ra > 0, and the confluent hypergeometric function U(a, b; z) for b ∈ C, Ra > 0, and Rz > 0. We derive two convergent expansions of M(a, b; z); ...
  • Convergent expansions of the incomplete gamma functions in terms of elementary functions 

    Bujanda Cirauqui, Blanca Upna; López García, José Luis; Pagola Martínez, Pedro Jesús (World Scientific Publishing, 2017)   Artículo / Artikulua  OpenAccess
    We consider the incomplete gamma function γ(a,z) for Ra>0 and z∈C. We derive several convergent expansions of z−aγ(a,z) in terms of exponentials and rational functions of z that hold uniformly in z with Rz bounded from ...
  • The use of two-point Taylor expansions in singular one-dimensional boundary value problems I 

    Ferreira, Chelo; López García, José Luis; Pérez Sinusía, Ester (Elsevier, 2018)   Artículo / Artikulua
    We consider the second-order linear differential equation (x + 1)y′′ + f(x)y′ + g(x)y = h(x) in the interval (−1, 1) with initial conditions or boundary conditions (Dirichlet, Neumann or mixed Dirichlet-Neumann). The ...
  • A simplification of the stationary phase method: application to the Anger and Weber functions 

    López García, José Luis (Kent State UniversityJohann Radon Institute (RICAM), 2017)   Artículo / Artikulua  OpenAccess
    The main difficulty in the practical use of the stationary phase method in asymptotic expansions of integrals is originated by a change of variables. The coefficients of the asymptotic expansion are the coefficients of the ...
  • Convergent expansions of the Bessel functions in terms of elementary functions 

    López García, José Luis; Pagola Martínez, Pedro Jesús (Springer US, 2018)   Artículo / Artikulua  OpenAccess
    We consider the Bessel functions Jν (z) and Yν (z) for ν > −1/2 and z ≥ 0. We derive a convergent expansion of Jν (z) in terms of the derivatives of (sin z)/z, and a convergent expansion of Yν (z) in terms of derivatives ...
  • Analytic formulas for the evaluation of the Pearcey integral 

    López García, José Luis; Pagola Martínez, Pedro Jesús (American Mathematical Society, 2017)   Artículo / Artikulua  OpenAccess
    We can find in the literature several convergent and/or asymptotic expansions of the Pearcey integral P(x, y) in different regions of the complex variables x and y, but they do not cover the whole complex x and y planes. The ...
  • 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. ...
  • 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 ...
  • 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 ...
  • 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 ...
  • Reconstrucción 3D mediante sensor de infrarrojos para la medición del volumen del brazo en pacientes con linfedema 

    Remírez Moreno, Berta (2018)   Trabajo Fin de Máster/Master Amaierako Lana
    El linfedema del brazo afecta a miles de personas y es necesario controlar el volumen de éste para comprobar que no haya retención de líquidos. Para esto, se compara el volumen del brazo sin operar con el volumen del ...
  • Recubrimiento biopolimérico para dispositivos de estimulación cardiaca 

    Martínez de Cestafe Rodríguez, Nagore (2018)   Trabajo Fin de Máster/Master Amaierako Lana
    En este proyecto fin de master se recoge el trabajo realizado en la empresa i+Med. El objetivo ha sido crear un recubrimiento polimérico biocompatible para los dispositivos de ...

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