Now showing items 2-21 of 116

    A census for curves and surfaces with diophantine stability over finite fields 

    Vrioni, Brikena (Date of defense: 2021-10-29)

    An algebraic variety defined over a field is said to have Diophantine stability for an extension of this field if the variety does not acquire new points in the extension. Diophantine stability has a growing interest due ...

    A geometric study of abnormality in optimal control problems for control and mechanical control systems 

    Barbero Liñán, María (Date of defense: 2008-12-19)

    Durant els darrers quaranta anys la geometria diferencial ha estat una eina fonamental per entendre la teoria de control òptim. Habitualment la millor estratègia per resoldre un problema és transformar-lo en un altre ...

    A hesitant fuzzy perceptual-based approach to model linguistic assessments 

    Porro Martorell, Olga (Date of defense: 2021-04-07)

    Multiple-criteria or multiple-attribute group decision-making is a sub-field of operations research that seek to find a common and representative solution given the preferences elicited by a pre-defined group, over a set ...

    A study on structure recovery and the broadcasting problem 

    Velona, Vasiliki (Date of defense: 2021-09-17)

    The thesis contains a study of two problems of combinatorial statistics. The first one is structure learning for partial correlation graphs and the second one is the broadcasting problem on certain families of random ...

    A theoretical and computational study of the active self-organization of nematic patterns in thin cytoskeletal layers and their effect on curvature 

    Mirza, Waleed Ahmad (Date of defense: 2023-02-16)

    (English)The structure and dynamics of important biological systems, ranging from cytoskeletal gels to tissues, are controlled by an interplay between activity, dissipation, nematic order, density, and geometry. In particular, ...

    A theoretical and computational study of the interaction between biomembranes and curved proteins 

    Tozzi, Caterina (Date of defense: 2021-04-30)

    Organelles are the smallest functional parts of eukaryotic cells. Among them, some are membrane-bound such as the nucleus, the endoplasmic reticulum, or the Golgi apparatus, each of them with essential biological functions. ...

    Active superelasticity in three-dimensional epithelia of controlled shape 

    Latorre Ibars, Ernest (Date of defense: 2021-02-19)

    Fundamental processes in development and physiology are determined by the three-dimensional architecture of epithelial sheets. How these sheets deform and fold into complex structures has remained unclear, however, because ...

    Additive structures and randomness in combinatorics 

    Spiegel, Christoph (Date of defense: 2020-07-03)

    Arithmetic Combinatorics, Combinatorial Number Theory, Structural Additive Theory and Additive Number Theory are just some of the terms used to describe the vast field that sits at the intersection of Number Theory and ...

    Advanced cryptographic techniques for building verifiable and transparent electronic voting protocols 

    Escala Ribas, Alex (Date of defense: 2017-07-21)

    Electronic voting presents many challenges due to its multiple security requirements. Some of the challenges are related to guaranteeing voters' privacy and system's transparency, which are hard to satisfy simultaneously. ...

    Algebraic and algorithmic aspects of Zm × Fn : fixed subgroups and quantification of inertia 

    Roy, Mallika (Date of defense: 2020-02-12)

    This work is based on the family of groups Z^m x F_n, namely free-abelian times free groups, direct products of finitely many copies of Z and a finitely generated free group F_n. These are a special type of right-angled ...

    Algebraic and semi-algebraic phylogenetic reconstruction 

    Garrote López, Marina (Date of defense: 2021-07-22)

    Phylogenetics is the study of the evolutionary history and relationships among groups of biological entities (called taxa). The modeling of those evolutionary processes is done by phylogenetic trees whose nodes represent ...

    Algorithms and Methods for Robust Geodetic kinematic Positioning 

    Talaya López, Julià (Date of defense: 2003-06-27)

    El sistema NAVSTAR/GPS ha desenvolupat un paper molt important en les tècniques de posicionament cinemàtic geodèsiques, especialment en la determinació de la trajectòries per a la orientació de sensors aerotransportats ...

    An effective method to study the Hopf-Galois module structure of certain extensions of fields 

    Gil-Muñoz, Daniel (Date of defense: 2021-07-02)

    We develop a method to compute a basis of the associated order in a Hopf Galois structure H of the ring of integers O_L of an extension of number or p-adic fields L/K. We state and prove a necessary and sufficient condition ...

    Anàlisi d'un model de suspensió-amortiment 

    Pellicer Sabadí, Marta (Date of defense: 2004-09-17)

    DE TESI DOCTORAL.<br/>Els sistemes formats per una molla fixa en un extrem i una massa rígida en moviment en l'altre, s'han modelitzat clàssicament mitjançant l'EDO de segon ordre mu''(t) + du'(t) + ku(t) = 0. Però aquest ...

    Aportación al estudio del software necesario para la informatización de los métodos de aprendage de las técnicas de expresión gráfica, y su posterior implementación 

    Castillo Baliarda, Miquel (Date of defense: 1988-05-07)

    ESTUDIO DEL EFECTO DE LA MICROINFORMATICA EN EL PROCESO DE APRENDIZAJE DE LAS TECNICAS DE EXPRESION GRAFICA (T.E.G.). LA MICROINFORMATICA Y LOS PROGRAMAS DE CAD (DISEÑO ASISTIDO POR ORDENADOR) PUEDEN REPRESENTAR UN NUEVO ...

    Arithmetic applications of the Euler systems of Beilinson-Flach elements and diagonal cycles 

    Rivero Salgado, Óscar (Date of defense: 2021-02-12)

    The main objective of this dissertation is the exploration of certain arithmetic applications of the Euler systems of Beilinson--Flach elements and diagonal cycles. Euler systems have been proved to be a very powerful tool ...

    Aspectos geométricos del control disipativo de sistemas mecànicos y sistemas no holónomos 

    Yániz Fernández, Francisco Javier (Date of defense: 2002-11-29)

    El tratamiento intrínseco de cuestiones relacionadas con la Teoría de Control no lineal a través de la aplicación de técnicas propias de la geometría diferencial ha sido en los últimos años un tema de interés para muy ...

    Bernstein-Sato polynomial of plane curves and Yano's conjecture 

    Blanco Fernández, Guillem (Date of defense: 2020-04-16)

    The main aim of this thesis is the study of the Bernstein-Sato polynomial of plane curve singularities. In this context, we prove a conjecture posed by Yano about the generic b-exponents of a plane irreducible curve. In ...

    bm-Symplectic manifolds: symmetries, classification and stability 

    Planas Bahí, Arnau (Date of defense: 2020-09-30)

    This thesis explores classification and perturbation problems for group actions on a class of Poisson manifolds called $b^m$-Poisson manifolds. $b^m$-Poisson manifolds are manifolds which are symplectic away from a ...

    Categories de descens: aplicacions a la teoría K algebraica 

    Rubió Pons, Llorenç (Date of defense: 2008-07-08)

    En el marc de l'estudi de la cohomologia de les varietats algebraiques, i en particular en les aplicacions cohomològiques del teorema de resolució de singularitats d'Hironaka, utilitzem la tècnica de les hiperresolucions ...