Browsing Τμήμα Μαθηματικών και Στατιστικής / Department of Mathematics and Statistics by Title

Now showing items 626-645 of 1633

    • Article  

      K-sample subsampling in general spaces: The case of independent time series 

      Politis, Dimitris Nicolas; Romano, J. P. (2010)
      The problem of subsampling in two-sample and K-sample settings is addressed where both the data and the statistics of interest take values in general spaces. We focus on the case where each sample is a stationary time ...
    • Article  

      Kansa RBF method for nonlinear problems 

      Jankowska, Małgorzata; Karageorghis, Andreas; Chen, CS (2018)
      We apply the Kansa–radial basis function (RBF) collocation method to two– dimensional nonlinear boundary value problems. The system of nonlinear equations resulting from the Kansa–RBF discretization is solved by directly ...
    • Article  

      A Kansa-Radial Basis Function Method for Elliptic Boundary Value Problems in Annular Domains 

      Liu, X. -Y; Karageorghis, Andreas; Chen, C. S. (2015)
      We employ a Kansa-radial basis function (RBF) method for the numerical solution of elliptic boundary value problems in annular domains. This discretization leads, with an appropriate selection of collocation points and for ...
    • Article  

      Kansa-RBF algorithms for elliptic problems in axisymmetric domains 

      Karageorghis, Andreas; Chen, C. S.; Liu, X. -Y (2016)
      We employ a Kansa-radial basis function method for the numerical solution of elliptic boundary value problems in three-dimensional axisymmetric domains. We consider problems governed by the Poisson equation, the inhomogeneous ...
    • Article  

      Kansa-RBF algorithms for elliptic problems in regular polygonal domains 

      Karageorghis, Andreas; Jankowska, Malgorzata A.; Chen, C. S. (2018)
      We propose matrix decomposition algorithms for the efficient solution of the linear systems arising from Kansa radial basis function discretizations of elliptic boundary value problems in regular polygonal domains. These ...
    • Conference Object  

      A Kansa-RBF method for Poisson problems in annular domains 

      Karageorghis, Andreas; Chen, C. S. (WITPress, 2014)
      We employ a Kansa-radial basis function (RBF) method for Poisson boundary value problems in annular domains. This discretization leads, for any choice of RBF, to linear system matrices possessing block circulant structures. ...
    • Article  

      Kernel estimates of nonparametric functional autoregression models and their bootstrap approximation 

      Zhu, T.; Politis, Dimitris Nicolas (2017)
      This paper considers a nonparametric functional autoregression model of order one. Existing contributions addressing the problem of functional time series prediction have focused on the linear model and literatures are ...
    • Article  

      A Kolmogorov inequality for U-statistics based on Bernoulli kernels 

      Christofides, Tasos C. (1994)
      A Kolmogorov inequality for the class of U-statistics based on kernels which are Bernoulli random variables is presented. This class of statistics contains the sample average of i.i.d. Bernoulli random variables as a special ...
    • Article  

      L1-Adaptive control: Stability, robustness, and interpretations 

      Ioannou, Petros A.; Annaswamy, A. M.; Narendra, K. S.; Jafari, S.; Rudd, L.; Ortega, R.; Boskovic, J. (2014)
      An adaptive control design approach that involves the insertion of a strictly proper stable filter at the input of standard Model Reference Adaptive Control (MRAC) schemes has been proposed in the recent years. This approach ...
    • Article  

      L2-approximations of power and logarithmic functions with applications to numerical conformal mapping 

      Maymeskul, V. V.; Saff, E. B.; Stylianopoulos, Nikos S. (2002)
      For a bounded Jordan domain G with quasiconformal boundary L, two-sided estimates are obtained for the error in best L2(G) polynomial approximation to functions of the form (z - τ)β, β > -1, and (z - τ)m logl(z - τ), m > ...
    • Article  

      Laminar axisymmetric flow of a weakly compressible viscoelastic fluid 

      Housiadas, Kostas D.; Georgiou, Georgios C.; Mamoutos, Ioannis G. (2012)
      The combined effects of weak compressibility and viscoelasticity in steady, isothermal, laminar axisymmetric Poiseuille flow are investigated. Viscoelasticity is taken into account by employing the Oldroyd-B constitutive ...
    • Article  

      Laminar jets of Bingham-plastic liquids 

      Ellwood, K. R. J.; Georgiou, Georgios C.; Papanastasiou, T. C.; Wilkes, J. O. (1990)
      The steady and transient behavior of jets generated by circular and slit nozzles are analyzed by the Galerkin finite-element method with free-surface parametrization and Newton iteration. A novel constitutive equation is ...
    • Article  

      Laminar Newtonian jets at high Reynolds number and high surface tension 

      Georgiou, Georgios C.; Papanastasiou, T. C.; Wilkes, J. O. (1988)
    • Conference Object  

      Lane change guidance for freeway incident management 

      Wang, Y.; Chang, H.; Ioannou, Petros A. (2009)
      This study proposes a design and evaluation method of lane change guidance system for freeway incident management. Microscopic simulator VISSIM is used to facilitate the design and evaluation. Sixteen incident scenarios ...
    • Article  

      The Laplace equation with discontinuous boundary data: Convergence of the spectral element discretization 

      Bernardi, C.; Karageorghis, Andreas (1997)
      We prove an existence result for the Laplace equation in a disk with discontinuous Dirichlet boundary conditions: 0 on part of the boundary and 1 on its complement. The problem is discretized by the mortar spectral element ...
    • Article  

      Laplace type invariants for variable coefficient mKdV equations 

      Tsaousi, Christina; Tracinà, Rita; Sophocleous, Christodoulos (2015)
      We consider a class of variable-coefficient mKdV equations. We derive the equivalence transformations in the infinitesimal form and we employ them to construct differential invariants of the respective equivalence algebra. ...
    • Article  

      Laplace type invariants for variable coefficient mKdV equations[ONLINE] 

      Tsaousi, Christina; Tracinà, Rita; Sophocleous, Christodoulos (2015)
    • Article  

      Large sample theory for statistics of stable moving averages 

      McElroy, T.; Politis, Dimitris Nicolas (2004)
      We study the limit behavior of the partial sums, sample variance, and periodogram of the stable moving average process x(t)= ∫ ψ(t + x)double struck M sign (dx) explored in Resnick, S., Samorodnitsky, G., and Xue, F. (1999). ...
    • Article  

      Large-sample inference in the general AR(1) model 

      Paparoditis Efstathios, E.; Politis, Dimitris Nicolas (2000)
      The situation where the available data arise from a general AR(1) model is discussed, and two new avenues for constructing confidence intervals for the unknown autoregressive root are proposed, one based on a Central Limit ...
    • Article  

      Large-sample inference in the general AR(1) modelAAA 

      Paparoditis Efstathios, E.; Politis, Dimitris Nicolas (2000)
      The situation where the available data arise from a general AR(1) model is discussed, and two new avenues for constructing confidence intervals for the unknown autoregressive root are proposed, one based on a Central Limit ...