In this study, a numerical solution of singular nonlinear differential equations, stemming from biology and physiology problems, is proposed. The methodology is based on the shifted Chebyshev polynomials operational matrix of derivative and collocation. To assess the accuracy of the method, five numerical problems, such as the human head, Oxygen diffusion and Bessel differential equation, were ...

For diffraction gratings with layered refractive index profiles, the Fourier modal method is widely used. However, it is quite expensive to calculate the eigenmodes for each layer, especially when the structure involves absorptive media. We develop an efficient method that avoids the eigenvalue problems based on the so-called Dirichlet-to-Neumann (DtN) map. For each layer, the DtN map is an ope...

When one approximates elliptic equations by the spectral collocation method on the Chebyshev-Gauss-Lobatto (CGL) grid, the resulting coefficient matrix is dense and illconditioned. It is known that a good preconditioner, in the sense that the preconditioned system becomes well conditioned, can be constructed with finite difference on the CGL grid. However, there is a lack of an efficient solver...

If the solution of an integral equation can be expanded in the form of a Chebyshev series, the equation can be transformed into an infinite set of algebraic equations in which the unknowns are the coefficients of the Chebyshev series. The algebraic equations are solved by standard iterative procedures, in which it is not necessary to determine beforehand how many coefficients are significant. T...

and Applied Analysis 3 nonlinear term is treated with the Chebyshev collocation method. The time discretization is a classical Crank-Nicholson-leap-frog scheme. Yuan and Wu 43 extended the Legendre dual-Petrov-Galerkin method proposed by Shen 44 , further developed by Yuan et al. 45 to general fifth-order KdV-type equations with various nonlinear terms. The main aim of this paper is to propose ...

In this paper, we will solve the Logistic and Riccati di¤erential equations using VIM, shifted Chebyshev-spectral fourth kind methods and Hermite collocation method. Where we can from the numerical results we obtained to conclude that the solution using these three approaches converge to the exact solution is excellent. We note that we can apply the proposed methods to solve other problems in e...

Abstract The new rational a -polynomials are used to solve the Falkner-Skan equation. These polynomials equipped with an auxiliary parameter. approximated solution equation is obtained by unknown coefficients. To find coefficients and parameter contained in polynomials, collocation method Chebyshev-Gauss points used. numerical examples show efficiency of this method.