Discrete Modified Projection Methods for Urysohn Integral Equations with Green's Function Type Kernels

In the present paper we consider discrete versions of the modified projection methods for solving a Urysohn integral equation with a kernel of the type of Green's function. For $r \geq 0,$ a space of piecewise polynomials of degree $\leq r$ with respect to an uniform partition is chosen to be the approximating space. We define a discrete orthogonal projection onto this space and replace the Urysohn integral operator by a Nystr\"{o}m approximation. The order of convergence which we obtain for the discrete version indicates the choice of numerical quadrature which preserves the orders of convergence in the continuous modified projection methods. Numerical results are given for a specific example.Comment: This is the the same paper with the arXiv identifier 1904.07895, but the shortened version. A bit change in the title als

An improvement of the product integration method for a weakly singular Hammerstein equation

We present a new method to solve nonlinear Hammerstein equations with weakly singular kernels. The process to approximate the solution, followed usually, consists in adapting the discretization scheme from the linear case in order to obtain a nonlinear system in a finite dimensional space and solve it by any linearization method. In this paper, we propose to first linearize, via Newton method, the nonlinear operator equation and only then to discretize the obtained linear equations by the product integration method. We prove that the iterates, issued from our method, tends to the exact solution of the nonlinear Hammerstein equation when the number of Newton iterations tends to infinity, whatever the discretization parameter can be. This is not the case when the discretization is done first: in this case, the accuracy of the approximation is limited by the mesh size discretization. A Numerical example is given to confirm the theorical result

Superconvergence of the Iterated Galerkin Methods for Hammerstein Equations

In this paper, the well-known iterated Galerkin method and iterated Galerkin-Kantorovich regularization method for approximating the solution of Fredholm integral equations of the second kind are generalized to Hammerstein equations with smooth and weakly singular kernels. The order of convergence of the Galerkin method and those of superconvergence of the iterated methods are analyzed. Numerical examples are presented to illustrate the superconvergence of the iterated Galerkin approximation for Hammerstein equations with weakly singular kernels. © 1996, Society for Industrial and Applied Mathematic

Approximate Analytical Methods For Solving Fredholm Integral Equations

Persamaan kamiran memainkan peranan penting dalam banyak bidang sains seperti matematik, biologi, kimia, fizik, mekanik dan kejuruteraan. Oleh yang demikian,pelbagai teknik berbeza telah digunakan untuk menyelesaikan persamaan jenis ini. Kajian ini, memfokus kepada analisis secara matematik dan berangka bagi beberapa kes persamaan kamiran Fredholm yang linear dan bukan linear. Kes-kes ini termasuklah persamaan kamiran Fredholm satu dimensi jenis pertama dan kedua, persamaan kamiran Fredholm dua dimensi jenis pertama dan kedua dan sistem persamaan kamiran Fredholm satu dimensi dan dua dimensi. Integral equations play an important role in many branches of sciences such as mathematics, biology, chemistry, physics, mechanics and engineering. Therefore, many different techniques are used to solve these types of equations. This study focuses on the mathematical and numerical analysis of some cases of linear and nonlinear Fredholm integral equations. These cases are one-dimensional Fredholm integral equations of the first kind and second kind, two-dimensional Fredholm integral equations of the first kind and second kind and systems of one and two-dimensional Fredholm integral equations