Abstract (EN):
Error Bounds and Discretization Grids in the
Solution of Weakly Singular Integral Equations∗
F. D. d’Almeida†
Universidade do Porto, Portugal
M. Ahues‡
Universit´e de Saint-´Etienne, France
R. Fernandes§
Universidade do Minho, Portugal
In the solution of weakly singular second kind Fredholm integral equations defined on
the space of Lebesgue integrable complex valued functions by projection-type methods such
as Petrov-Galerkin or Kantorovitch methods [1], the choice of the discretization grids is
crucial. We will present the proof of an error bound in terms of the mesh size of the
underlying discretization grid on which no regularity assumptions are made and compare
it wiht other recently proposed error bounds [2]. This allows us to use non regular grids
which is convenient when there are boundary layers or discontinuities in the right hand side
function of the equation. We present some results using a simplified model of the radiative
transfer in stellar atmospheres which illustrates the actual behaviour of the error in terms
of the distribution of the points in the grid.
References
[1] K. Atkinson, The numerical solution of integral equations of the second kind, n. 4 in Cambridge
Monographs on Applied and Computational Mathematics, Cambridge University Press, 1997.
[2] M. Ahues, A. Amosov, A. Largillier, Superconvergence of some projection approximations for
weakly singular integral equations using general grids, SIAM J. Numer. Anal. 47 (2009), no. 1,
646–674
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Language:
English
Type (Professor's evaluation):
Scientific
Contact:
http://www.math.unipd.it/~dwcaa09