Now showing items 1-20 of 64

    • A characterization of isochronous centres in terms of symmetries 

      Freire, Emilio; Gasull Embid, Armengol; Guillamon Grabolosa, Antoni (2000)
      Article
      Open Access
      We present a description of isochronous centres of planar vector fields $X$ by means of their groups of symmetries. More precisely, given a normalizer $U$ of $X$ (i.e., $[X,U]=\mu X$, where $\mu$ is a scalar function), we ...
    • A note on the periodic orbits and topological entropy of graph maps 

      Alseda Soler, Lluís; Juher, D.; Mumbrú i Rodriguez, Pere (2000)
      Article
      Open Access
      This paper deals with the relationship between the periodic orbits of continuous maps on graphs and the topological entropy of the map. We show that the topological entropy of a graph map can be approximated by the entropy ...
    • A note on the totally transitive graph maps 

      Alseda Soler, Lluís; Río, M.A. del; Rodríguez Méndez, José Ángel (2000)
      Article
      Open Access
    • A pseudo-normal form for planar vector fields 

      Delshams Valdés, Amadeu; Guillamon Grabolosa, Antoni; Lázaro Ochoa, José Tomás (2001)
      Article
      Open Access
    • A study on the generation of chaos due to the presence of smale horseshoes in dynamical systems with a homoclinic orbit 

      Deulofeu Matas, Pol (Universitat Politècnica de Catalunya, 2020-07)
      Master thesis
      Open Access
      One of the fundamental problems in dynamical systems is the detection and characterisation of chaotic behaviours. In this work we will focus on chaos induced by what is called the Smale horseshoe. Smale horseshoes frequently ...
    • An example on Lyapunov stability and linearization 

      Munhoz Rodrigues, Hildebrando; Solà-Morales Rubió, Joan de (2020-01-01)
      Article
      Restricted access - publisher's policy
      The purpose of this paper is to present an example of a (in the Fréchet sense) discrete dynamical system in a infinite-dimensional separable Hilbert space for which the origin is an exponentially asymptotically stable ...
    • An invertible contraction that is not C<sup>1</sup>-linearizable 

      Munhoz Rodrigues, Hildebrando; Solà-Morales Rubió, Joan de (2004)
      Article
      Open Access
      We present an example of a smooth invertible contraction in aninfinite-dimensional Hilbert space that is not locally ${\mathcalC}^{1}$-linearizable near its fixed point.
    • Analysis of a viscoelastic spring-mass model 

      Pellicer Sabadí, Marta; Solà-Morales Rubió, Joan de (2003)
      Article
      Open Access
      In this paper we consider a linear wave equation with strong damping and dynamical boundary conditions as an alternative model for the classical spring-mass-damper ODE. Our purpose is to compare analytically these two ...
    • Analysis of periodic solutions of the system Janus - Epimetheus 

      Huesca Molina, Luis (Universitat Politècnica de Catalunya, 2016-07)
      Bachelor thesis
      Open Access
      Desenvolupament d'un model 2-dimensional per el sistema coorbital de Janus i Epimetheus al voltant de Saturn, afegint l'aplanament del planeta. Demostracio d'un teorema de simetries sobre les equacions de moviment i analisi ...
    • Assessment of the depth of anesthesia based on symbolic dynamics of the EEG 

      Tupaika, Nadine; Vallverdú Ferrer, Montserrat; Jospin, Mathieu; Jensen, Erik Weber; Struys, Michel M. R. F.; Vereecke, Hugo E. M.; Voss, Andreas; Caminal Magrans, Pere (2010)
      Conference lecture
      Open Access
      Methodologies based on symbolic dynamics have successfully demonstrated to reflect the nonlinear behavior of biological signals. In the present study, symbolic dynamics was applied to the electroencephalogram (EEG) in ...
    • Astrophysical parameter determination using chaotic orbital regions 

      Nicolás Álvarez, Jorge (Universitat Politècnica de Catalunya, 2018-02-27)
      Master thesis
      Open Access
      Covenantee:   European Space Research and Technology Centre
      The goal of this thesis is to show that chaotic orbits of a dynamical system are advantageous (compared with regularnes) to determine the characteristic parameters of the system, and to give an estimate about the behaviour ...
    • Asymptotic behaviour of the domain of analyticity of invariant curves of the standard map 

      Martínez-Seara Alonso, M. Teresa; Villanueva Castelltort, Jordi (1999)
      Article
      Open Access
      In this paper we consider the standard map, and we study the invariant curve obtained by analytical continuation, with respect to the perturbative parameter E, of the invariant circle of rotation number the golden mean ...
    • Axiomatic definition of the topological entropy on the interval 

      Alseda Soler, Lluís; Kolyada, Sergi; Llibre Saló, Jaume; Snoha, Lubomír (2000)
      Article
      Open Access
      Summary. The aim of this paper is to give an axiomatic definition of the topological entropy for continuous interval maps and, in such a way, to shed some more light on the importance of the different properties of the ...
    • Coarse-grained probabilistic automata mimicking chaotic systems 

      Falcioni, Massimo; Vulpiani, Angelo; Mantica, Giorgio; Pigolotti, Simone (2003-07-24)
      Article
      Open Access
      Discretization of phase space usually nullifies chaos in dynamical systems. We show that if randomness is associated with discretization dynamical chaos may survive and be indistinguishable from that of the original chaotic ...
    • Communication through coherence in a realistic neuronal model 

      Reyner Parra, David (Universitat Politècnica de Catalunya, 2020-07)
      Master thesis
      Open Access
      The Communication Through Coherence (CTC) theory establishes that neural communication is much effective if the underlying oscillatory activity of both populations are phase locked, that is, the input from the emitting ...
    • Computation of the invariant manifolds of infinity in the restricted circular planar three body problem with the parametrization method 

      Font i Reverter, Jordi (Universitat Politècnica de Catalunya, 2017-05)
      Master thesis
      Open Access
      This work analyses the parabolic stable manifolds of the periodic orbits at infinity for the Restricted Planar Circular Three Body Problem. Using the parametrization method we prove the existence of such manifold and we ...
    • Computer-Assited Proofs in Dynamics 

      Fernández Pinto, Aaron (Universitat Politècnica de Catalunya, 2020-10)
      Master thesis
      Restricted access - author's decision
      Interval analysis is presented as a solution to obtain rigorous results using computers. We present a methodology of computer-assisted proofs which involves the use of interval computations. In this thesis we introduce the ...
    • De la mecànica celeste als sistemes dinàmics: un camí d'anar i tornar 

      Simó, Carles (2006-05-17)
      Audiovisual
      Open Access
      La Mecànica Celeste estudia el moviment dels astres i, en general, tot tema relacionat amb el problema dels N cossos i les seves aplicacions a la ciència espacial. Podem considerar que el seu origen remot és el coneixement ...
    • Differentiable invariant manifolds for partially hyperbolic tori and a lambda lemma 

      Fontich i Julià, Ernest; Martín de la Torre, Pablo (2000)
      Article
      Open Access
      We consider differentiable maps having an invariant torus with normal behavior having a central part. We prove the existence and regularity of pseudostable manifolds and regularity with respect to parameters. Then we ...
    • Dynamics and bifurcation near the transition from stability to complex instability 

      Ollé Torner, Mercè; Pacha Andújar, Juan Ramón; Villanueva Castelltort, Jordi (2001)
      Article
      Open Access