High-order finite difference methods are efficient, easy to program, scale well in multiple dimensions and can be modified locally for various reasons (such as shock treatment for example). The main drawback has been the complicated and sometimes even mysterious stability treatment at boundaries and interfaces required for a stable scheme. The research on summation-byparts operators and weak bo...

and Applied Analysis 3 The grid function y(x, t) is a function defined at the grid points of g. we denote the nodal values of a grid function y(x, t) between time levels t 0 and t 0 as y (x, t) = y (x 1 , x 2 , t l,j i ) = y l,j n1 ,n2 , (11) for x ∈ ω i , i > 0, j = 0, . . . , m i . For x ∈ ω 0 we define y (x, t) = y (x 1 , x 2 , t l+1 0 ) = y l+1 n1 ,n2 . (12) δ x1 , δ x1 and δ x2 , δ x2 are ...

In this paper, we propose and study a diffusive HIV infection model with infected cells delay, virus mature abstract function incidence rate diffusion term. By introducing the reproductive numbers for viral R0 CTL immune response number R1, show that R1 act as threshold parameter existence stability of equilibria. If R0≤1, infection-free equilibrium E0 is globally asymptotically stable, viruses...

The stability and convergence properties of the mimetic finite difference method for diffusion-type problems on polyhedral meshes are analyzed. The optimal convergence rates for the scalar and vector variables in the mixed formulation of the problem are proved.

The error generated by the classical upwind finite difference method on a uniform mesh, when applied to a class of singularly perturbed model ordinary differential equations with a singularly perturbed Neumann boundary condition, tends to infinity as the singular perturbation parameter tends to zero. Note that the exact solution is uniformly bounded with respect to the perturbation parameter. F...

It is important to simulate a groundwater transport process, e.g., pollutant migration, through the vadose zone and subsequent mixing within the saturated zone to assess potential impacts of contaminants in the subsurface in preliminary stages. It is challenging to simulate heterogeneous soil characteristics and non-uniform initial contaminant concentration. This paper proposes a vertically het...

The results of computations with eight explicit finite difference schemes on a suite of one-dimensional and two-dimensional test problems for the Euler equations are presented in various formats. Both dimensionally split and two-dimensional schemes are represented, as are central and upwind-biased methods, and all are at least second-order accurate.

A finite difference method is developed for solving symmetric positive differential equations in the sense of Friedrichs. The method is applicable to partial differential equations of mixed type with more general boundary conditions. The method is shown to have a convergence rate of 0(hxl2), h being the size of mesh grid. Some numerical results are presented for a model problem of forward-backw...