Results 11 to 20 of about 113,433 (127)
A Higher-Order Energy Expansion to Two-Dimensional Singularly Neumann Problems [PDF]
, 2005 Of concern is the following singularly perturbed semilinear elliptic problem \begin{equation*} \left\{ \begin{array}{c} \mbox{${\epsilon}^2\Delta u -u+u^p =0$ in $\Omega$}\\ \mbox{$u>0$ in $\Omega$ and $
Yeung, W-K, Winter, M, Wei, J
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Maximum norm a posteriori error estimate for a 2d singularly perturbed semilinear reaction-diffusion problem [PDF]
, 2008 A singularly perturbed semilinear reaction-diffusion equation, posed in the unit square, is discretized on arbitrary nonuniform tensor-product meshes. We establish a second-order maximum norm a posteriori error estimate that holds true uniformly in the ...
Kopteva, Natalia
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Maximum norm a posteriori error estimation for parabolic problems using elliptic reconstructions [PDF]
, 2013 A semilinear second-order parabolic equation is considered in a regular and a singularly perturbed regime. For this equation, we give computable a posteriori error estimates in the maximum norm.
Linss, Torsten, Kopteva, Natalia
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Time delays and pollution in an open‐access fishery
Natural Resource Modeling, Volume 36, Issue 2, May 2023., 2023 Abstract We analyze the impacts of pollution on fishery sector using a dynamical system approach. The proposed model presupposes that the economic development causes emissions that either remediate or accumulate in the oceans. The model possesses a block structure where the solutions of the rate equations for the pollutant and the economic activity act
Harald Bergland +4 more
wiley +1 more source
International Journal of Intelligent Systems, Volume 2023, Issue 1, 2023., 2023 The proposed research utilizes a computational approach to attain a numerical solution for the singularly perturbed delay differential equation (SPDDE) problem arising in the neuronal variability model through artificial neural networks (ANNs) with different solvers. The log‐sigmoid function is used to construct the fitness function. The implementation
Iftikhar Ahmad +6 more
wiley +1 more source
Mathematical Problems in Engineering, Volume 2023, Issue 1, 2023., 2023 This study deals with the numerical solution of parabolic convection‐diffusion problems involving two small positive parameters and arising in modeling of hydrodynamics. To approximate the solution, the backward Euler method for time stepping and fitted trigonometric‐spline scheme for spatial discretization are considered on uniform meshes.
Tariku Birabasa Mekonnen +2 more
wiley +1 more source
Parameter‐uniform numerical methods for singularly perturbed linear transport problems
Mathematical Methods in the Applied Sciences, Volume 45, Issue 17, Page 11224-11245, 30 November 2022., 2022 Pointwise accurate numerical methods are constructed and analysed for three classes of singularly perturbed first order transport problems. The methods involve piecewise‐uniform Shishkin meshes and the numerical approximations are shown to be parameter‐uniformly convergent in the maximum norm.
José Luis Gracia +2 more
wiley +1 more source
Advances in Mathematical Physics, Volume 2022, Issue 1, 2022., 2022 In this study, an efficient analytical method called the Sumudu Iterative Method (SIM) is introduced to obtain the solutions for the nonlinear delay differential equation (NDDE). This technique is a mixture of the Sumudu transform method and the new iterative method.
Asfaw Tsegaye Moltot +2 more
wiley +1 more source
Journal of Mathematics, Volume 2022, Issue 1, 2022., 2022 This work analyze singularly perturbed convection‐diffusion‐reaction (CDR) models with two parameters and variable coefficients by developing a mesh‐free scheme based on local radial basis function‐finite difference (LRBF‐FD) approximation. In the evolvement of the scheme, time derivative is discretized by forward finite difference. After that, LRBF‐FD
Ram Jiwari +3 more
wiley +1 more source
A singularly perturbed semilinear reaction-diffusion problem in a polygonal domain [PDF]
, 2010 The semilinear reaction-di®usion equation ¡"24u+b(x; u) = 0 with Dirichlet bound-ary conditions is considered in a convex polygonal domain. The singular perturbation parameter ε is arbitrarily small, and the “reduced equation” b(x, u0 (x)) = 0 may have ...
Kellogg, R. Bruce, Kopteva, Natalia
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