Now showing items 21-40 of 44

    Boundedness of the Hilbert Transform on Weighted Lorentz Spaces 

    Agora, Elona (Date of defense: 2012-07-13)

    The main goal of this thesis is to characterize the weak-type (resp. strong-type) boundedness of the Hilbert transform H on weighted Lorentz spaces Λpu(w). The characterization is given in terms of some geometric ...

    Detection and Alignment of Vascular Structures in Intravascular Ultrasound using Pattern Recognition Techniques 

    Alberti, Marina (Date of defense: 2013-02-21)

    In this thesis, several methods for the automatic analysis of Intravascular Ultrasound (IVUS) sequences are presented, aimed at assisting physicians in the diagnosis, the assessment of the intervention and the monitoring ...

    Capacitary function spaces and applications 

    Silvestre Albero, María Pilar (Date of defense: 2012-02-08)

    The first part of the thesis is devoted to the analysis on a capacity space, with capacities as substitutes of measures in the study of function spaces. The goal is to extend to the associated function lattices some aspects ...

    Connectivity of Julia sets of transcendental meromorphic functions 

    Taixés i Ventosa, Jordi (Date of defense: 2011-09-22)

    Newton's method associated to a complex holomorphic function f is defined by the dynamical system Nf(z) = z – f(z) / f'(z). As a root-finding algorithm, a natural question is to understand the dynamics of Nf about its fixed ...

    Por qué la difusión de Arnold aparece genéricamente en los sistemas hamiltonianos con más de dos grados de libertad. 

    Delshams, Amadeu (Date of defense: 1984-01-01)

    El teorema de Kolmogorov-Arnold-Moser no asegura la estabilidad cerca de los toros m-dimensionales que se conservan para hamiltonianos casi integrables con "m" grados de libertad. Puede aparecer una difusión de trayectorias ...

    Morfismos diferenciables topológicamente lisos. Caracterizaciones y aplicaciones 

    Ortega Aramburu, Joaquín Mª (Date of defense: 1972-01-01)

    Esta memoria recoge algunos de los puntos fundamentales e inéditos que han aparecido al iniciar un estudio sobre los métodos espectrales en Análisis y, en particular, sobre los anillos y estructuras diferenciables. Dicho ...

    Real analysis in non-euclidean spaces: trees and spaces of homogeneous type 

    Garcia Domingo, Josep Lluís (Date of defense: 2003-01-01)

    DE LA TESIS:<br/><br/>El contenido de esta tesis se enmarca dentro del Análisis Real. En particular, trata del estudio de ciertos problemas de la teoría de pesos, (una referencia clásica sobre esta teoría es el libro de ...

    On Quasiperiodic Perturbations of Ordinary Differential Equations 

    Jorba i Monte, Àngel (Date of defense: 1991-10-11)

    In this work we study several topics concerning quasi-periodic time-dependent perturbations of ordinary differential equations. This kind of equations appear as models in many applied problems of Celestial Mechanics, and ...

    The Role and Usage of Libration Point Orbits in the Earth - Moon System 

    Alessi, Elisa Maria (Date of defense: 2010-10-04)

    In this dissertation, we show the effectiveness of the exploitation of the Circular Restricted Three - Body Problem (CR3BP) in the Earth - Moon framework. We study the motion of a massless particle under the gravitational ...

    Mesura del trencament de separatrius en famílies de difeomorfismes amb punts hiperbòlics 

    Fontich Julià, Ernest (Date of defense: 1985-12-05)

    Se consideran familias de difeomorfismos con un punto fijo parabólico para el valor cero del parámetro y un punto fijo hiperbólico para valores mayores que cero que tengan en este caso puntos homoclínicos asociados a ...

    Contribució a l'estudi del problema restringit de 3 cossos per a valors petits del paràmetre de masses 

    Benseny Ardiaca, Antoni (Date of defense: 1984-09-03)

    El problema de 3 cossos i, en particular, el problema restringit de 3 cossos, ha estat i és, com diu Wintner, la pedra de toc per als matemàtics de les successives generacions de Newton fins ara. Cada generació ha emprat ...

    Transference theory between quasi-Banach function spaces with applications to the restriction of Fourier multipliers. 

    Rodríguez López, Salvador (Date of defense: 2008-04-07)

    In the early 1970 fs, R. Coifman and G. Weiss, generalizing the techniques introduced by A. Calderon, developed a method for transferring abstract convolution type operators, defined on general topological groups, and their ...

    Design and evaluation of navigation and control algorithms for spacecraft formation flying missions 

    Perea Virgili, Laura (Date of defense: 2010-05-21)

    Formation flying offers space-dependent disciplines such as astrophysics, astrodynamics, and geodesy, to name a few, the possibility of creating large spaceborne sensors from an array of small spacecraft flying in formation. ...

    Mesures i probabilitats en estructures ordenades 

    Congost Iglesias, Maria Assumpta (Date of defense: 1981-01-01)

    En una primera part s'estudien els conjunts de mesures que prenen valors en un grup reticualt, per a les quals la T-aditivitat es defineix a partir de l'estructura ordenada. L'estudi realitzat a partir de les propietats ...

    The Primitive Function of an Exact Symplectomorphism. Variational principles, Converse KAM Theory and the problems of determination and interpolation 

    Haro, Àlex (Date of defense: 1998-10-02)

    We have divided this thesis in four parts:<br/><br/>a) PART I: Exact symplectic geometry (introduction of the problems). This part contains the basic tools of symplectic geometry and outlines the four subjects that we have ...

    Estudi de sistemes dinàmics mitjançant la reducció de la seva dimensió 

    Bosch Gual, Miquel (Date of defense: 1992-09-30)

    L'objectiu del treball és mostrar que alguns aspectes de certs sistemes dinàmics discrets bidimensionals poden ser estudiats mitjançant sistemes de dimensió 1 que corresponen a casos particulars o simplificacions. Els tres ...

    Invariant manifolds and bifurcations for one-dimensional and two-dimensional dissipative maps 

    Tatjer i Montaña, Joan Carles (Date of defense: 1990-03-01)

    It is known that for the study of continuous dynamical systems the discret case plays an important role because, with it we can study the continuous one by using the Poincaré return map. In the discret case we can distinguish ...

    Interpolación compleja de operadores lineales 

    Carro Rossell, María Jesús (Date of defense: 1988-01-30)

    El primer resultado de interpolación de operadores data del año 1911 y es debido a I. Schur. Dos años más tarde, Young prueba un resultado del mismo tipo referente a espacios Lp y a un operador L La extensión de estos ...

    Qualitative analysis of the anisotropic Kepler problem 

    Casasayas i Mas, Josefa (Date of defense: 1984-01-01)

    The anisotropic Kepler problem was introduced by Gutzwiller as a classical mechanical system which approximates the following quantum mechanical system: the study of bound states of an electron near a donor impurity of a ...

    On the Meromorphic Non-Integrability of Some Problems in Celestial Mechanics 

    Simon i Estrada, Sergi (Date of defense: 2007-07-09)

    In this thesis, we present a proof of the meromorphic non-integrability for some problems arising from Celestial Mechanics, as well as a new necessary condition for partial integrability in a wider Hamiltonian setting. ...