Ara es mostren els items 32-41 de 41

    • Reduction and reconstruction of multisymplectic Lie systems 

      de Lucas Araujo, Javier; Gràcia Sabaté, Francesc Xavier; Ribas León, Xavier; Román Roy, Narciso; Vilariño Fernández, Silvia (Institute of Physics (IOP), 2022-07-22)
      Article
      Accés obert
      A Lie system is a non-autonomous system of first-order ordinary differential equations describing the integral curves of a non-autonomous vector field taking values in a finite-dimensional real Lie algebra of vector fields, ...
    • Skinner–Rusk formalism for k-contact systems 

      Gràcia Sabaté, Francesc Xavier; Rivas Guijarro, Xavier; Román Roy, Narciso (2022-02-01)
      Article
      Accés obert
      In previous papers, a geometric framework has been developed to describe non-conservative field theories as a kind of modified Lagrangian and Hamiltonian field theories. This approach is that of k-contact Hamiltonian ...
    • Structural aspects of Hamilton–Jacobi theory 

      Cariñena Marzo, José F.; Gràcia Sabaté, Francesc Xavier; Marmo, Giuseppe; Martínez Fernandez, Eduardo; Muñoz Lecanda, Miguel Carlos; Román Roy, Narciso (2016-02-01)
      Article
      Accés obert
      In our previous papers [11, 13] we showed that the Hamilton–Jacobi problem can be regarded as a way to describe a given dynamics on a phase space manifold in terms of a family of dynamics on a lower-dimensional manifold. ...
    • The wave equation for stiff strings and piano tuning 

      Gràcia Sabaté, Francesc Xavier; Sanz Perela, Tomás (2017)
      Article
      Accés obert
      We study the wave equation for a string with stiffness. We solve the equation and provide a uniqueness theorem with suitable boundary conditions. For a pinned string we compute the spectrum, which is slightly inharmonic. ...
    • Time-dependent contact mechanics 

      de León Rodríguez, Manuel; Gaset Rifà, Jordi; Gràcia Sabaté, Francesc Xavier; Muñoz Lecanda, Miguel Carlos; Rivas Guijarro, Xavier (2022-09-16)
      Article
      Accés obert
      Contact geometry allows us to describe some thermodynamic and dissipative systems. In this paper we introduce a new geometric structure in order to describe time-dependent contact systems: cocontact manifolds. Within this ...
    • VARIETATS DIFERENCIABLES 

      Gràcia Sabaté, Francesc Xavier (Universitat Politècnica de Catalunya, 2017-01-10)
      Examen
      Accés restringit a la comunitat UPC
    • VARIETATS DIFERENCIABLES 

      Gràcia Sabaté, Francesc Xavier (Universitat Politècnica de Catalunya, 2015-01-16)
      Examen
      Accés restringit a la comunitat UPC
    • VARIETATS DIFERENCIABLES 

      Gràcia Sabaté, Francesc Xavier (Universitat Politècnica de Catalunya, 2021-01-21)
      Examen
      Accés restringit a la comunitat UPC
    • VARIETATS DIFERENCIABLES 

      Gràcia Sabaté, Francesc Xavier (Universitat Politècnica de Catalunya, 2019-01-15)
      Examen
      Accés restringit a la comunitat UPC
    • VARIETATS DIFERENCIABLES - FINAL 

      Gràcia Sabaté, Francesc Xavier (Universitat Politècnica de Catalunya, 2023-01-13)
      Examen
      Accés restringit a la comunitat UPC