We develop and analyze a meshfree discretization method for Darcy’s problem. Our approximation scheme is based upon optimal recovery which leads to a collocation scheme using divergence-free positive definite kernels. Besides producing analytically incompressible flow fields, our method can be of arbitrary order, works in arbitrary space dimension and for arbitrary geometries. After deriving th...

The classical problem of homogenization deals with elliptic operators in periodically oscillating media of small period ε > 0 and the asymptotic behavior of solution u of boundary value problems associated with such operators. In a previous work [5], the authors introduced what is called Bloch approximation which provided energy norm approximation for the solution in R . This paper continues wi...

The paper is devoted to the analysis of two different approaches for numerical simulation gaseous combustion. first one based on a full system Navier-Stokes equations describing dynamics compressible reactive medium, while second utilizes low-Mach number approximation. model realized by traditional low-order scheme and contemporary CABARET method. approach implemented base widely known FDS sche...

Numerical results are presented for the shock-boundary layer interactions in a hypersonic flow over a sharp leading edge compression corner. In this study, a second- order Godunov type scheme based on solving a Generalized Riemann Problem (GRP) at each cell interface is used to solve thin shear layer approximation of laminar Navier-Stokes (N-S) equations. The calculated flow-field shows general...

Bivariate Fréchet (BF) copulas characterize dependence as a mixture of three simple structures: comonotonicity, independence and countermonotonicity. They are easily interpretable but have limitations when used as approximations to general dependence structures. To improve the approximation property of the BF copulas and keep the advantage of easy interpretation, we develop a new copula approxi...

in this paper, we have proposed a numerical method for singularly perturbed  fourth order ordinary differential equations of convection-diffusion type. the numerical method combines boundary value technique, asymptotic expansion approximation, shooting method and  finite difference method. in order to get a numerical solution for the derivative of the solution, the given interval is divided  in...

In order to improve the approximation of spatial derivatives without meshes, a set of meshfree numerical schemes for derivative terms is developed, which is compatible with the coordinates of Cartesian, cylindrical, and spherical. Based on the comparisons between numerical and theoretical solutions, errors and convergences are assessed by a posteriori method, which shows that the approximations...

we consider an approximation scheme using haar wavelets for solving a class of infinite horizon optimal control problems (ocp's) of nonlinear interconnected large-scale dynamic systems. a computational method based on haar wavelets in the time-domain is proposed for solving the optimal control problem. haar wavelets integral operational matrix and direct collocation method are utilized to ...

Lawler [E.L. Lawler, A fully polynomial approximation scheme for the total tardiness problem, Operations Research Letters 1 (1982) 207–208] proposed a fully polynomial approximation scheme for the single-machine total tardiness problem which runs in O n 7 e time (where n is the number of jobs and e is the desired level of approximation). A faster fully polynomial approximation scheme running in...

In this paper, we investigate the performance issue of PNNl routing for ATM networks. A brief introduction to PNNI routing protocol is given. We extend the reduced load approximation algorithm to ATM networks with PNNI routing. A hierarchical reduced load approximation scheme is proposed The scheme includes two steps: the reduced load approximation algorithm is first applied on the aggregated n...