• Article  

      Classification of noether symmetries for Lagrangians with three degrees of freedom 

      Damianou, Pantelis A.; Sophocleous, Christodoulos (2004)
      The noether symmetries of the Euler-Lagrange equations for a Hamiltonian system with three degrees were classified. All groups were classified that appeared as symmetries of a general Hamiltonians system of n degrees of ...
    • Article  

      A Legendre spectral Galerkin method for the biharmonic Dirichlet problem 

      Bialecki, B.; Karageorghis, Andreas (2001)
      A Legendre spectral Galerkin method is presented for the solution of the biharmonic Dirichlet problem on a square. The solution and its Laplacian are approximated using the set of basis functions suggested by Shen, which ...
    • Article  

      The method of fundamental solutions for the identification of a sound-soft obstacle in inverse acoustic scattering 

      Karageorghis, Andreas; Johansson, B. T.; Lesnic, D. (2012)
      In this paper we propose a simple meshless method of fundamental solutions (MFS) for detecting a sound-soft scatterer embedded in a host acoustic homogeneous medium from the measurement of the far-field pattern of the ...
    • Article  

      Modelling interventions in INGARCH processes 

      Liboschik, T.; Kerschke, P.; Fokianos, Konstantinos; Fried, R. (2016)
      We study different approaches for modelling intervention effects in time series of counts, focusing on the so-called integer-valued GARCH models. A previous study treated a model where an intervention affects the non-observable ...
    • Article  

      Newtonian flow in a triangular duct with slip at the wall 

      Georgiou, Georgios C.; Kaoullas, G. (2013)
      We consider the Newtonian Poiseuille flow in a tube whose cross-section is an equilateral triangle. It is assumed that boundary slip occurs only above a critical value of the wall shear stress, namely the slip yield stress. ...
    • Article  

      Newtonian Poiseuille flows with slip and non-zero slip yield stress 

      Kaoullas, G.; Georgiou, Georgios C. (2013)
      The Newtonian Poiseuille flow is considered for various geometries, under the assumption that wall slip occurs above a critical value of the wall shear stress known as, the slip yield stress. In the axisymmetric and planar ...
    • Article  

      The Toda lattice is super-integrable 

      Agrotis, Maria A.; Damianou, Pantelis A.; Sophocleous, Christodoulos (2006)
      We prove that the classical, non-periodic Toda lattice is super-integrable. In other words, we show that it possesses 2 N - 1 independent constants of motion, where N is the number of degrees of freedom. The main ingredient ...