Now showing items 1-20 of 101

  • Abundance of attracting, repelling and elliptic periodic orbits in two-dimensional reversible maps 

    Delshams Valdés, Amadeu; Gonchenko, S.V.; Lázaro Ochoa, José Tomás; Stenkin, Oleg (2013-01-01)
    Article
    Open Access
    We study dynamics and bifurcations of two-dimensional reversible maps having non-transversal heteroclinic cycles containing symmetric saddle fixed points. We consider one-parameter families of reversible maps unfolding ...
  • A comparison of high-order time integrators for thermal convection in rotating spherical shells 

    García González, Fernando; Net Marcé, Marta; Garcia-Archilla, Bosco; Sánchez Umbría, Juan (2010-10-01)
    Article
    Open Access
    A numerical study of several time integration methods for solving the threedimensional Boussinesq thermal convection equations in rotating spherical shells is presented. Implicit and semi-implicit time integration ...
  • A geometric mechanism of diffusion: rigorous verification in a priori unstable Hamiltonian systems 

    Delshams Valdés, Amadeu; Huguet Casades, Gemma (2011-03-01)
    Article
    Restricted access - publisher's policy
    In this paper we consider a representative a priori unstable Hamiltonian system with 2 + 1/2 degrees of freedom and we apply the geometric mechanism for diffusion introduced in [A. Delshams, R. de la Llave, T.M. Seara, ...
  • A Hamiltonian study of the stability and bifurcations for the satellite problem 

    Muñoz Lecanda, Miguel Carlos; Rodríguez Olmos, Miguel Andrés; Teixidó Román, Miguel (2015-10-01)
    Article
    Open Access
    We study the dynamics of a rigid body in a central gravitational field modeled as a Hamiltonian system with continuous rotational symmetries following the geometric framework of Wang et al. Novelties of our work are the ...
  • Àlgebra i equacions diferencials 

    Batlle Arnau, Carles; Massana Hugas, Immaculada; Zaragoza Monroig, M. Luisa (Edicions UPC, 2000)
    Book
    Restricted access to the UPC academic community
    Aquesta obra està orientada, de manera general, a les enginyeries tècniques i, d'una manera específica, a l'assignatura Àlgebra i Equacions Diferencials que s'imparteix a diverses titulacions de l'EUPVG. El seu objectiu ...
  • An analytical approach to codimension-2 sliding bifurcations in the dry friction oscillator 

    Martínez-Seara Alonso, M. Teresa; Guàrdia Munarriz, Marcel; Hogan, S. John (2010)
    Article
    Restricted access - publisher's policy
    In this paper, we analytically consider sliding bifurcations of periodic orbits in the dry-friction oscillator. The system depends on two parameters: F, which corresponds to the intensity of the friction, and ω, the ...
  • An efficient iterative method for computing deflections of Bernoulli–Euler–von Karman beams on a nonlinear elastic foundation 

    Ahmad, Fayyaz; Jang, Taek Soo; Carrasco, Juan A.; Shafiq Ur, Rehman; Ali, Zulfiqar; Ali, Nukhaze (2018-10-01)
    Article
    Restricted access - publisher's policy
    An efficient iterative method is developed for the static analysis of large deflections of an infinite beam with variable cross-section resting on a nonlinear foundation. A pseudo spring constant is added and explicit ...
  • A new multisymplectic unified formalism for second order classical field theories 

    Prieto Martínez, Pedro Daniel; Román Roy, Narciso (American Institute of Mathematical Sciences, 2015-06-01)
    Article
    Open Access
    We present a new multisymplectic framework for second-order classical field theories which is based on an extension of the unified LagrangianHamiltonian formalism to these kinds of systems. This model provides a straightforward ...
  • A new subdivision algorithm for the flow propagation using polynomial algebras 

    Pérez Palau, Daniel; Gómez Muntané, Gerard; Masdemont Soler, Josep (2018-08-01)
    Article
    Restricted access - publisher's policy
    The Jet Transport method has emerged as a powerful tool for the numerical integration of ordinary differential equations; it uses polynomial expansions to approximate the flow map associated to the differential equation ...
  • A note on the symplectic topology of b-manifolds 

    Miranda Galcerán, Eva; Martinez Torres, David; Frejlich, Pedro (2017)
    Article
    Open Access
    Poisson manifold (M2n; ) is b-symplectic if Vn is transverse to the zero section. In this paper we apply techniques native to Symplectic Topology to address questions pertaining to b-symplectic manifolds. We pro- vide ...
  • A Parameterized multi-step Newton method for solving systems of nonlinear equations 

    Ahmad, Fayyaz; Tohidi, Emran; Carrasco, Juan A. (2016-03-01)
    Article
    Open Access
    We construct a novel multi-step iterative method for solving systems of nonlinear equations by introducing a parameter. to generalize the multi-step Newton method while keeping its order of convergence and computational ...
  • A priori estimates for semistable solutions of semilinear elliptic equations 

    Cabré Vilagut, Xavier; Sanchón Rodellar, Manuel; Spruck, Joel (2016-02-01)
    Article
    Open Access
    We consider positive semistable solutions u of Lu + f(u) = 0 with zero Dirichlet boundary condition, where L is a uniformly elliptic operator and f is an element of C-2 is a positive, nondecreasing, and convex nonlinearity ...
  • Aproximación del problema de Stokes mediante elementos finitos mixtos de tipo cross-grid 

    Blasco Lorente, Jorge; Armentano, María G. (2009)
    Conference lecture
    Restricted access - publisher's policy
    En esta comunicación introducimos una familia de métodos de elementos finitos mixtos para la resolución numérica del problema de Stokes en dimensión 2. En estos métodos, la presión se interpola en una malla de elementos ...
  • A singular initial value problem to construct density-equalizing maps 

    Avinyó Andrés, Albert; Solà-Morales Rubió, Joan de; València Guitart, Marta (2011-05)
    External research report
    Open Access
    The diffusion-based algorithm to produce density-equalizing maps interprets diffusion as an advection process. This algorithm uses the dynamics of a flow that is defined by an initial value problem that turns out to be ...
  • A smooth center manifold theorem which applies to some III-posed partial differential equations with unbounded nonlinearities 

    Llave Canosa, Rafael de la (2009)
    Article
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    We prove the existence of a smooth center manifold for several partial differential equations, including ill posed equations with unbounded nonlinearities. We also prove smooth dependence on parameters with respect to ...
  • A Survey of the hysteretic Duhem model 

    Ikhouane, Fayçal (2018-11-01)
    Article
    Restricted access - publisher's policy
    The Duhem model is a simulacrum of a com- plex and hazy reality: hysteresis. Introduced by Pierre Duhem to provide a mathematical representation of thermodynamical irreversibility, it is used to ...
  • Asymptotic behavior of palais-smale sequences associated with fractional yamabe-type equations 

    Fang, Yi; González Nogueras, María del Mar (2015-12-01)
    Article
    Open Access
    In this paper, we analyze the asymptotic behavior of Palais-Smale sequences associated to fractional Yamabe-type equations on an asymptotically hyperbolic Riemannian manifold. We prove that Palais-Smale sequences can be ...
  • Boundedness of stable solutions to semilinear elliptic equations: A survey 

    Cabré Vilagut, Xavier (2017-05-01)
    Article
    Open Access
    This article is a survey on boundedness results for stable solutions to semilinear elliptic problems. For these solutions, we present the currently known L8 estimates that hold for all nonlinearities. Such estimates are ...
  • Bounded solutions of second order lineal difference equations with periodic coefficients 

    Encinas Bachiller, Andrés Marcos; Jiménez Jiménez, María José (2016)
    Conference report
    Open Access
  • 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
    Restricted access - publisher's policy
    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 ...