Ara es mostren els items 40084-40103 de 88187

  • El "fracking" a Catalunya 

    Dorda Fernández, Mariona (Universitat Politècnica de Catalunya, 2016-02-24)
    Treball Final de Grau
    Accés restringit per decisió de l'autor
  • Fractal antennas 

    Puente Baliarda, Carles (Universitat Politècnica de Catalunya, 1997-06-30)
    Tesi
    Accés obert
    Las antenas son dispositivos esencialmente de banda estrecha; es decir, su comportamiento es altamente dependiente de la frecuencia de operación. La relación entre la longitud de onda de trabajo y el tamaño de la antena ...
  • Fractal approach of turbulent dispersion 

    Redondo Apraiz, José Manuel (CNRS, éditeur, 2010)
    Text en actes de congrés
    Accés obert
    There are several techniques suitable for measuring and modelling dispersion from scalar or velocity-field measurements in a turbulent flow. Each of these has peculiar features and sometimes, even different scaling, and a ...
  • Fractal design of multiband and low side-lobe arrays 

    Puente Baliarda, Carles; Pous Andrés, Rafael (1996-05)
    Article
    Accés obert
    Most array factor design techniques are highly dependent on the operating wavelength. In this paper, a novel technique based on fractal structures is described for multiband operation. The analysis is focused in two different ...
  • Fractal dimension analysis of malignant and benign endobronchial ultrasound nodes 

    Fiz Fernández, José Antonio; Monte Moreno, Enrique; Andreo, Felipe; Auteri, Santiago Jose; Sanz Santos, Jose; Serra Coromina, Pere; Bonet, Gloria; Castella, Eva; Ruiz Manzano, Juan (2014-06-12)
    Article
    Accés obert
    Background: Endobronchial ultrasonography (EBUS) has been applied as a routine procedure for the diagnostic of hiliar and mediastinal nodes. The authors assessed the relationship between the echographic appearance of ...
  • Fractal FSS: a novel dual band frequency selective surface 

    Romeu Robert, Jordi; Rahmat-Samii, Yahya (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2000-07-31)
    Article
    Accés obert
    The multiband properties of self-similar fractals can be advantageously exploited to design multiband frequency selective surfaces (FSS). A Sierpinski dipole FSS has been analyzed and measured and the results show an ...
  • Fractal multiband antenna based on the sierpinski gasket 

    Puente Baliarda, Carles; Romeu Robert, Jordi; Pous Andrés, Rafael; García, X; Benítez, F (Institution of Electrical Engineers, 1996-01)
    Article
    Accés obert
    Experimental and computed results show a multiband behaviour over five bands for the new fractal Sierpinski antenna. Such a behaviour is based on the self-similarity properties of the antenna's fractal shape, which might ...
  • Fractal multiband patch antenna 

    Borja, C.; Puente Baliarda, Carles; Romeu Robert, Jordi; Anguera Pros, Jaume (European Space Agency (ESA), 2000)
    Text en actes de congrés
    Accés restringit per política de l'editorial
    The multiband behaviour of the Sierpinski patch antenna is described in this paper. Experimental results show that the self similarity properties of the fractal shape are translated into its electromagnetic behaviour.
  • Fractal negations 

    Mayor Forteza, Gaspar; Calvo Sánchez, Tomasa (Universitat Politècnica de Catalunya. Secció de Matemàtiques i Informàtica, 1994)
    Article
    Accés obert
    From the concept of attractor of a family of contractive affine transformations in the Euclidean plane R², we study the fractality property of the De Rham function and other singular functions wich derive from it. In ...
  • Fractal structure and predictability of distances between consecutive events: an analysis of three seismic aftershock sequences in Southern California 

    Martínez Santafé, Maria Dolors; Lana Pons, Francisco Javier; Monterrubio Velasco, Marisol; Serra de Larrocha, Carina (2015)
    Comunicació de congrés
    Accés obert
  • Fractal structure and predictive strategy of the daily extreme temperature residuals at Fabra Observatory (NE Spain, years 1917-2005) 

    Lana Pons, Francisco Javier; Burgueño, August; Serra de Larrocha, Carina; Martínez Santafé, Maria Dolors (2015-07-01)
    Article
    Accés restringit per decisió de l'autor
    A compilation of daily extreme temperatures recorded at the Fabra Observatory (Catalonia, NE Spain) since 1917 up to 2005 has permitted an exhaustive analysis of the fractal behaviour of the daily extreme temperature ...
  • Fractal-based reconstruction of point-set models of outdoor scenes. 

    Moya Santos, Sergio (Universitat Politècnica de Catalunya, 2011-09-03)
    Projecte Final de Màster Oficial
    Accés obert
    English: In the last few decades a number of methods have been proposed for the acquisition of 3D models from real objects, including 3D scanning, 3D point- based photography and image-based modeling, among others. These ...
  • Fractal-shaped antennas and their application to GSM 900/1800 

    Puente Baliarda, Carles; Anguera Pros, Jaume; Romeu Robert, Jordi; Borja, C.; Navarro, Mónica; Soler, Jordi (2001)
    Article
    Accés restringit per política de l'editorial
  • Els fractals com a recurs didàctic en el desenvolupament curricular de la tecnologia a l’ESO 

    Sánchez Vigil, Antonia (Universitat Politècnica de Catalunya, 2011-06-29)
    Projecte Final de Màster Oficial
    Accés obert
    Encara que objectes amb dimensió fractal estan presents a la Natura des de sempre (núvols, muntanyes, plantes,..), els Fractals i la Dimensió Fractal són conceptes matemàtics relativament recents però que compten ja ...
  • Fractional conformal Laplacians and fractional Yamabe problems 

    González Nogueras, María del Mar; Qing, Jie (2010-12)
    Report de recerca
    Accés obert
    Based on the relations between scattering operators of asymptotically hyperbolic metrics and Dirichlet-to-Neumann operators of uniformly degenerate elliptic boundary value problems observed in [11], we formulate fractional ...
  • Fractional DC-DC converter in solar-powered electrical generation systems 

    Martínez González, Rubén; Bolea Monte, Yolanda; Grau Saldes, Antoni; Martínez García, Herminio (2011)
    Article
    Accés restringit per política de l'editorial
    This paper deals with the fractional modeling of a DC-DC buck-boost converter, suitable in solar-powered electrical generation systems, and the design of a fractional controller for the aforementioned switching converter. ...
  • Fractional DC/DC Converter in Solar-Powered Electrical Generation Systems 

    Martínez González, Rubén; Bolea Monte, Yolanda; Grau Saldes, Antoni; Martínez García, Herminio (IEEE Press. Institute of Electrical and Electronics Engineers, 2009-09)
    Comunicació de congrés
    Accés obert
    This paper deals with the fractional modeling of a DC-DC buck-boost converter, suitable in solar-powered electrical generation systems, and the design of a fractional controller for the aforementioned switching ...
  • Fractional DC/DC converter in solar-powered electrical generation systems 

    Martínez González, Rubén; Bolea Monte, Yolanda; Grau Saldes, Antoni; Martínez García, Herminio (2010)
    Text en actes de congrés
    Accés restringit per política de l'editorial
    This paper deals with the fractional modelling of a DC-DC buck-boost converter, suitable in solarpowered electrical generation systems, and the design of a fractional controller for the aforementioned switching converter. ...
  • Fractional DC/DC converter in solar–powered electrical generation systems 

    Martínez, Rubén; Bolea Monte, Yolanda; Grau Saldes, Antoni; Martínez García, Herminio (2010)
    Article
    Accés restringit per política de l'editorial
    This paper deals with the fractional modeling of a DC-DC buck-boost converter, suitable in solar-powered electrical generation systems, and the design of a fractional controller for the aforementioned switching converter. ...
  • Fractional Laplacian in conformal geometry 

    González Nogueras, María del Mar; Chang, Sun-Yung Alice (2011-01-30)
    Article
    Accés restringit per política de l'editorial
    In this note, we study the connection between the fractional Laplacian operator that appeared in the recent work of Caffarelli and Silvestre and a class of conformally covariant operators in conformal geometry.