Now showing items 21-40 of 159

    • Breakdown of a 2D heteroclinic connection in the hopf-zero singularity (I) 

      Baldomá Barraca, Inmaculada; Castejón Company, Oriol; Martínez-Seara Alonso, M. Teresa (2018-10-01)
      Article
      Open Access
      In this paper we study a beyond all orders phenomenon which appears in the analytic unfoldings of the Hopf-zero singularity. It consists in the breakdown of a two-dimensional heteroclinic surface which exists in the truncated ...
    • Breakdown of a 2D heteroclinic connection in the Hopf-zero singularity (II): The generic case 

      Baldomá Barraca, Inmaculada; Castejón Company, Oriol; Martínez-Seara Alonso, M. Teresa (2018-04-17)
      Article
      Open Access
      In this paper, we prove the breakdown of the two-dimensional stable and unstable manifolds associated to two saddle-focus points which appear in the unfoldings of the Hopf-zero singularity. The method consists in obtaining ...
    • Chaos in the hysteretic grazing-sliding codimension-one saddle-node bifurcation of piecewise dynamical systems 

      Bonet Revés, Carles; Martínez-Seara Alonso, M. Teresa (UP4, Institute of Sciences, S.L., 2017)
      Conference lecture
      Open Access
      We present two ways of regularizing a parameter family of piecewise smooth dynamical systems undergoing a grazing- sliding bifurcation. We use the Sotomayor-Teixeira regularization and prove that the bifurcation is a ...
    • Chaotic advection, transport and patchiness in clouds of pollution in an estuarine flow 

      Stirling, James Robert (American Institute of Mathematical Sciences, 2001)
      Article
      Open Access
      We present an application of the transport theory developed for area preserving dynamical systems, to the problem of pollution and in particular patchiness in clouds of pollution in partially stratified estuaries. We ...
    • Chaotic dynamics of the Kepler problem with variable gravitational coefficient 

      Giralt Miron, Mar (Universitat Politècnica de Catalunya, 2017-07)
      Master thesis
      Open Access
      On this work we prove the presence of chaotic dynamics for the classical two-body Kepler problem with a time-periodic variable gravitational coefficient using two different methods, the stretching along the path (SAP) ...
    • Closed Geodesics and Billiards on Quadrics related to elliptic KdV solutions 

      Abenda, Simonetta; Fedorov, Yuri (2004)
      Article
      Open Access
      We consider algebraic geometrical properties of the integrable billiard on a quadric Q with elastic impacts along another quadric confocal to Q. These properties are in sharp contrast with those of the ellipsoidal Birkho® ...
    • Codimension-3 bifurcation for continuous saddle bimodal linear dynamical systems 

      Ferrer Llop, Josep; Peña Carrera, Marta; Susín Sánchez, Antonio (2018-02-01)
      Article
      Open Access
      We continue the study of the structural stability and the bifurcations of planar continuous bimodal linear dynamical systems (that is, systems consisting of two linear dynamics acting on each side of a straight line, ...
    • 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 invariant curves in the analysis of periodically forced neural oscillators 

      Pérez Cervera, Alberto; Huguet Casades, Gemma; Martínez-Seara Alonso, M. Teresa (Springer, 2018)
      Part of book or chapter of book
      Open Access
      Background oscillations, reflecting the excitability of neurons, are ubiq- uitous in the brain. Some studies have conjectured that when spikes sent by one population reach the other population in the peaks of excitability, ...
    • Computation of periodic orbits and their invariant manifolds in the RTBP 

      Martínez García, Miguel (Universitat Politècnica de Catalunya, 2014-07)
      Master thesis
      Open Access
      This project is a study of the RTBP, in particular of a modification of this problem devised to study orbits of the Moon. Some parts of the project are done analytically while others numerically. The analytical part focuses ...
    • 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, Aarón (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 ...
    • Continua of periodic points for planar integrable rational maps 

      Gasull Embid, Armengol; Llorens, Mireia; Mañosa Fernández, Víctor (Research India Publications, 2016-09)
      Article
      Open Access
      We present three alternative methodologies to find continua of periodic points with a prescribed period for rational maps having rational first integrals. The first two have been already used by other authors and apply ...
    • Continua of periodic points for planar integrable rational maps. 

      Gasull Embid, Armengol; Llorens, Mireia; Mañosa Fernández, Víctor (2015-11-30)
      Research report
      Open Access
      We present three alternative methodologies to find continua of periodic points with a prescribed period for rational maps having rational first integrals. The first two have been already used for other authors and apply ...
    • Coupling-mediated ghost resonance in mutually injected lasers 

      Martín Buldu, Javier; Martínez González, Cristina; Trull Silvestre, José Francisco; Torrent Serra, Maria del Carmen; García Ojalvo, Jordi (2005-03)
      Article
      Restricted access - publisher's policy
    • Critical velocity in kink solutions of the sine-Gordon equation 

      Sanchis Ramírez, Guillem (Universitat Politècnica de Catalunya, 2017-07)
      Master thesis
      Open Access
      The goal of this work is to present a way to deduce the value of the critical velocity observed in soliton-like solutions of a perturbed version of the sine-Gordon equation. To do so, an ODE system is obtained from the ...
    • Darboux integrability and invariant algebraic curves for planar polynomial systems 

      Christopher, C.; Llibre Saló, Jaume; Pantazi, Chara; Zhang, Xiang (2004)
      Article
      Open Access
      In this paper we study the normal forms of polynomial systems having a set of given generic invariant algebraic curves.
    • Detection of Lagrangian Coherent Structures in oceanic flows 

      Bruera, Renzo (Universitat Politècnica de Catalunya, 2021-07)
      Master thesis
      Open Access
      The Atlantic Meridional Overturning Circulation (AMOC) is a complex system of shallow and deep currents in the Atlantic Ocean which plays a crucial role in the regulation of the Earth's climate. Lagrangian Coherent Structures ...
    • Different approaches to the global periodicity problem 

      Cima Mollet, Anna; Gasull Embid, Armengol; Mañosa Fernández, Víctor; Mañosas, Francesc (2013-07-25)
      Research report
      Open Access
      t Let F be a real or complex n-dimensional map. It is said that F is globally periodic if there exists some p ∈ N + such that Fp(x) = x for all x, where F k = F ◦ F k−1, k ≥ 2. The minimal p satisfying this property is ...
    • Discrete nonholonomic LL systems on Lie groups 

      Fedorov, Yuri; Zenkov, Dmitry (2003)
      Article
      Open Access
      This paper applies the recently developed theory of discrete nonholonomic mechanics to the study of discrete nonholonomic left-invariant dynamics on Lie groups. The theory is illustrated with the discrete versions of two ...