Ara es mostren els items 17-36 de 72

    • Càlcul numèric 

      Bonet Revés, Carles; Jorba Monte, Angel; Martínez-Seara Alonso, M. Teresa; Masdemont Soler, Josep; Ollé Torner, Mercè; Susín Sánchez, Antonio; València Guitart, Marta (Edicions UPC, 1994)
      Llibre
      Accés restringit a la comunitat UPC
      El llibre Càlcul numèric conté les eines i bases fonamentals dels algotimes de computació. La seva presentació, exempta de formalismes excessivament teòrics, el fa molt adequat per al lector que, sense voler aprofundir ...
    • Cálculos numéricos de la Hopf zero 

      Larreal Barreto, Oswaldo José; Martínez-Seara Alonso, M. Teresa (2009)
      Comunicació de congrés
      Accés obert
      Consideramos la siguiente familia de campos X en R3 :  dx dt = − xz − y( + c z) + p+1f( x, y, z, ) dy dt = − yz + x( + c z) + p+1g( x, y, z, ) dz dt = (−1 + b(x2 + y2) + z2) + p+1h( x, y, z, ...
    • 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)
      Comunicació de congrés
      Accés obert
      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 ...
    • 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)
      Capítol de llibre
      Accés obert
      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, ...
    • Critical velocity in kink-defect interaction models: rigorous results 

      Martínez-Seara Alonso, M. Teresa; Guàrdia Munarriz, Marcel; Gomide, Otávio M.L. (2020-01-01)
      Article
      Accés obert
      In this work we study a model of interaction of kinks of the sine-Gordon equation with a weak defect. We obtain rigorous results concerning the so-called critical velocity derived in [7] by a geometric approach. More ...
    • Exponentially and non-exponentially small splitting of separatrices for the pendulum with a fast meromorphic perturbation 

      Guàrdia Munarriz, Marcel; Martínez-Seara Alonso, M. Teresa (2011-07)
      Report de recerca
      Accés obert
      In this paper we study the splitting of separatrices phenomenon which arises when one considers a Hamiltonian System of one degree of freedom with a fast periodic or quasiperiodic and meromorphic in the state variables ...
    • Exponentially Small Heteroclinic Breakdown in the Generic Hopf-Zero Singularity 

      Baldomá Barraca, Inmaculada; Castejón i Company, Oriol; Martínez-Seara Alonso, M. Teresa (2013)
      Article
      Accés restringit per política de l'editorial
      In this paper we prove the breakdown of a heteroclinic connection in the analytic versal unfoldings of the generic Hopf-zero singularity in an open set of the parameter space. This heteroclinic orbit appears at any order ...
    • Exponentially small splitting for the pendulum: a classical problem revisited 

      Martínez-Seara Alonso, M. Teresa; Guàrdia Munarriz, Marcel; Olivé, Carme (2010)
      Article
      Accés restringit per política de l'editorial
      In this paper, we study the classical problem of the exponentially small splitting of separatrices of the rapidly forced pendulum. Firstly, we give an asymptotic formula for the distance between the perturbed invariant ...
    • Exponentially small splitting for whiskered tori in Hamiltonian systems: Flow-box coordinates and upper bounds 

      Delshams Valdés, Amadeu; Gutiérrez Serrés, Pere; Martínez-Seara Alonso, M. Teresa (2003)
      Article
      Accés obert
      We consider a singular or weakly hyperbolic Hamiltonian, with $n+1$ degrees of freedom, as a model for the behaviour of a nearly-integrable Hamiltonian near a simple resonance. The model consists of an integrable Hamiltonian ...
    • Exponentially small splitting of separatrices beyond Melnikov analysis: rigorous results 

      Baldomá Barraca, Inmaculada; Fontich, Ernest; Guàrdia Munarriz, Marcel; Martínez-Seara Alonso, M. Teresa (2011)
      Report de recerca
      Accés obert
      In this paper we study the problem of exponentially small splitting of separatrices of one degree of freedom classical Hamiltonian systems with a non-autonomous perturbation which is fast and periodic in time. We provide ...
    • Exponentially small splitting of separatrices in the perturbed McMillan map 

      Martínez-Seara Alonso, M. Teresa; Martín de la Torre, Pablo; Sauzin, D. (2009-12)
      Report de recerca
      Accés obert
      The McMillan map is a one-parameter family of integrable symplectic maps of the plane, for which the origin is a hyperbolic fixed point with a homoclinic loop, with small Lyapunov exponent when the parameter is small. ...
    • Exponentially small splitting of separatrices in the perturbed McMillan map 

      Martín, Pau; Sauzin, D.; Martínez-Seara Alonso, M. Teresa (2011-10)
      Article
      Accés obert
      The McMillan map is a one-parameter family of integrable symplectic maps of the plane, for which the origin is a hyperbolic xed point with a homoclinic loop, with small Lyapunov exponent when the parameter is small. ...
    • Exponentially small splitting of separatrices under fast quasiperiodic forcing 

      Delshams Valdés, Amadeu; Gelfreich, Vassili; Jorba, Angel; Martínez-Seara Alonso, M. Teresa (1997)
      Article
      Accés obert
      We consider fast quasiperiodic perturbations with two frequencies $(1/\varepsilon,\gamma/\varepsilon)$ of a pendulum, where $\gamma$ is the golden mean number. The complete system has a two-dimensional invariant ...
    • Generalized analytical results on n-ejection–collision orbits in the RTBP: analysis of bifurcations 

      Martínez-Seara Alonso, M. Teresa; Ollé Torner, Mercè; Rodríguez del Río, Óscar; Soler Villanueva, Jaume (Springer Nature, 2023-02-01)
      Article
      Accés obert
      In the planar circular restricted three-body problem and for any value of the mass parameter µ¿(0,1) and n=1 , we prove the existence of four families of n-ejection–collision (n-EC) orbits, that is, orbits where the particle ...
    • Generic bifurcations of low codimension of planar Filippov Systems 

      Martínez-Seara Alonso, M. Teresa; Guàrdia Munarriz, Marcel; Teixeira, Marco Antonio (2011-02)
      Article
      Accés restringit per política de l'editorial
      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 ...
    • Generic bifurcations of low codimension of planar Filippov Systems 

      Guàrdia Munarriz, Marcel; Martínez-Seara Alonso, M. Teresa; Teixeira, Marco Antonio (2009-10)
      Report de recerca
      Accés obert
      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 ...
    • Global phase-amplitude description of oscillatory dynamics via the parameterization method 

      Pérez Cervera, Alberto; Martínez-Seara Alonso, M. Teresa; Huguet Casades, Gemma (Institute of Physics (IOP), 2020-08-01)
      Article
      Accés obert
      In this paper, we use the parameterization method to provide a complete description of the dynamics of an n-dimensional oscillator beyond the classical phase reduction. The parameterization method allows us, via efficient ...
    • Hopf-Zero singularities truly unfold chaos 

      Baldomá Barraca, Inmaculada; Ibáñez Mesa, Santiago; Martínez-Seara Alonso, M. Teresa (2020-05-01)
      Article
      Accés obert
      We provide conditions to guarantee the occurrence of Shilnikov bifurcations in analytic unfoldings of some Hopf-Zero singularities through a beyond all order phenomenon: the exponentially small breakdown of invariant ...
    • Instability of high dimensional Hamiltonian systems: Multiple resonances do not impede diffusion 

      Delshams Valdés, Amadeu; Llave Canosa, Rafael de la; Martínez-Seara Alonso, M. Teresa (2016-05-14)
      Article
      Accés obert
      We consider models given by Hamiltonians of the form View the MathML sourceH(I,f,p,q,t;e)=h(I)+¿j=1n±(12pj2+Vj(qj))+eQ(I,f,p,q,t;e) Turn MathJax on where I¿I¿Rd,f¿TdI¿I¿Rd,f¿Td, p,q¿Rnp,q¿Rn, t¿T1t¿T1. These are higher ...
    • Instability of high dimensional Hamiltonian systems: Multiple resonances do not impede diffusion 

      Delshams Valdés, Amadeu; de la Llave, Rafael; Martínez-Seara Alonso, M. Teresa (2013-06)
      Report de recerca
      Accés obert
      Abstract. We consider models given by Hamiltonians of the form H ( I;';p;q;t ; " ) = h ( I )+ n X j =1 1 2 p 2 j + V j ( q j ) + "Q ( I;';p;q;t ; " ) where I 2I R d ;' 2 T d ...