Now showing items 1-12 of 604

    • Exponentially small splitting of separatrices associated to 3D whiskered tori with cubic frequencies 

      Delshams Valdés, Amadeu; Gonchenko, Marina; Gutiérrez Serrés, Pere (2020-01-01)
      Article
      Open Access
      We study the splitting of invariant manifolds of whiskered (hyperbolic) tori with three frequencies in a nearly-integrable Hamiltonian system, whose hyperbolic part is given by a pendulum. We consider a 3-dimensional torus ...
    • The dynamics of digits: calculating Pi with Galperin's billiards 

      Aretxabaleta, Xabier M.; Gonchenko, Marina; Harshman, Nathan L.; Jackson, Steven Glenn; Olshanii, Maxim; Astrakharchik, Grigori (Multidisciplinary Digital Publishing Institute (MDPI), 2020-04-01)
      Article
      Open Access
      In Galperin billiards, two balls colliding with a hard wall form an analog calculator for the digits of the number p . This classical, one-dimensional three-body system (counting the hard wall) calculates the digits of p ...
    • Exponentially small splitting of separatrices associated to 3D whiskered tori with cubic frequencies 

      Delshams Valdés, Amadeu; Gonchenko, Marina; Gutiérrez Serrés, Pere (2019-06)
      External research report
      Open Access
      We study the splitting of invariant manifolds of whiskered (hyperbolic) tori with three frequencies in a nearly-integrable Hamiltonian system, whose hyperbolic part is given by a pendulum. We consider a 3-dimensional ...
    • On local and global aspects of the 1:4 resonance in the conservative cubic Hénon maps 

      Gonchenko, Marina; Gonchenko, Sergey; Ovsyannikov, Ivan; Vieiro, Arturo (Institute of Physics (IOP), 2018-04-30)
      Article
      Open Access
      We study the 1:4 resonance for the conservative cubic Hénon maps C^± with positive and negative cubic terms. These maps show up different bifurcation structures both for fixed points with eigenvalues¿±i and for 4-periodic ...
    • A numerical method for computing initial conditions of Lagrangian invariant tori using the frequency map 

      Villanueva Castelltort, Jordi; Luque Jiménez, Alejandro (2016-06-15)
      Article
      Open Access
      We present a numerical method for computing initial conditions of Lagrangian quasi-periodic invariant tori of Hamiltonian systems and symplectic maps. Such initial conditions are found by solving, using the Newton method, ...
    • Traveling wave solutions in a half-space for boundary reactions 

      Cabré Vilagut, Xavier; Consul Porras, M. Nieves; Mande Nieto, José Vicente (2015-01-01)
      Article
      Open Access
      We prove the existence and uniqueness of a traveling front and of its speed for the homogeneous heat equation in the half-plane with a Neumann boundary reaction term of unbalanced bistable type or of combustion type. We ...
    • A note on symplectic and Poisson linearization of semisimple Lie algebra actions 

      Miranda Galcerán, Eva (2015-03)
      External research report
      Open Access
      In this note we prove that an analytic symplectic action of a semisimple Lie algebra can be locally linearized in Darboux coordinates. This result yields simultaneous analytic linearization for Hamiltonian vector fields ...
    • Generic bifurcations of low codimension of planar Filippov Systems 

      Martínez-Seara Alonso, M. Teresa; Guàrdia Munarriz, Marcel; Teixeira, Marco Antonio (2011-02)
      Article
      Restricted access - publisher's policy
      In this article some qualitative and geometric aspects of non-smooth dynamical systems theory are discussed. The main aim of this article is to develop a systematic method for studying local(and global) bifurcations in ...
    • A distributed attitude control law for formation flying based on the Cucker-smale model 

      Paita, Fabrizio; Gómez Muntané, Gerard; Masdemont Soler, Josep (2014)
      Conference report
      Open Access
      In this paper we consider the attitude synchronization problem for a swarm of spacecrafts flying in formation. Starting from previous works on consensus dynamics, we construct a distributed attitude control law and derive ...
    • Matrices positivas y aplicaciones 

      García Planas, María Isabel (Maria Isabel Garcia Planas, 2008-09-01)
      Book
      Open Access
    • Credit risk contributions under the Vasicek one-factor model: a fast wavelet expansion approximation 

      Masdemont Soler, Josep; Ortiz-Gracia, Luis (2014-06)
      Article
      Open Access
      To measure the contribution of individual transactions inside the total risk of a credit portfolio is a major issue in financial institutions. VaR Contributions (VaRC) and Expected Shortfall Contributions (ESC) have become ...
    • Com les Varietats Invariants formen Espirals i Anells en Galàxies barrades 

      Romero Gómez, Mercè; Sánchez-Martín, Patricia; Masdemont Soler, Josep (2014)
      Article
      Open Access
      L'espectacularitat de les galàxies barrades consisteix no solament en la presència de la barra, allargada en el centre de la galàxia, sinó també en els braços espirals o anells que es desenvolupen en les parts exteriors. ...