In this paper we develop an alternative method to derive finite difference approximations of derivatives. The purpose is to find schemes which work for a broader range of frequencies than the usual approximations based on polynomial fitting and Taylor’s Theorem to the expense of less accuracy for low frequencies. The numerical schemes are obtained as solutions to constrained optimizations probl...

Compact high-order upwind schemes using reconstruction from cell-averages are derived for application with the compressible three-dimensional Navier-Stokes equations. An adaptive-octree mesh, combined with the Adams-BashforthMoulton family of predictor-corrector schemes, provides a conservative highorder time-integration platform supporting localized h-refinement and timestep sub-cycling. Numer...

Several relaxation approximations to partial differential equations have been recently proposed. Examples include conservation laws, Hamilton-Jacobi equations, convection-diffusion problems, gas dynamics problems. The present paper focuses onto diffusive relaxation schemes for the numerical approximation of nonlinear parabolic equations. These schemes are based on suitable semilinear hyperbolic...

Implicit time integration schemes that inherit the conservation laws of total energy, linear and angular momentum are considered for initial boundary-value problems in ®nite-deformation elastodynamics. Conserving schemes are constructed for general hyperelastic material models, both compressible and incompressible, and are formulated in a way that is independent of spatial discretization. Three...

The time domain solution of the equations of motion of structures subjected to a stochastic wind field is often obtained by a step-by-step integration approach. The loading is described by simulated time histories of the aerodynamic force. Recently, autoregressive and moving average (ARMA) recursive models have been utilized to simulate the time series of wind loads. Based on the system dynamic...

We analyze the behavior of Euler-Maclaurin-based integration schemes with the intention of deriving accurate and economic estimations of the error term.

The dynamic response analysis of structures subjected to a stochastic wind field is carried out in the time domain by a step-by-step integration approach. The loading is represented by simulated time histories of the aerodynamic force. The auto-regressive and moving average (ARMA) recursive models are utilized to simulate time series of wind loads. Depending on the system dynamic characteristic...

there are fragmentations in iran’s health insurance system. multiple health insurance funds exist, without adequate provisions for transfer or redistribution of cross subsidy among them. multiple risk pools, including several private secondary insurance schemes, have resulted in a tiered health insurance system with inequitable benefit packages for different segments of the population. also fra...

† IEEE Network Mag., Mar. 1995, pp. 49–56. ATM is the first switching technology that can support both fixed bandwidth services similar to circuit switching, and highly variable bandwidth services similar to packet switching, in a single integrated environment [1]. Definitions for traffic management for services with a fixed traffic profile were completed by the ATM Forum in their version 3.0 s...

In modern logistics operations, large-scale logistics companies, besides active participation in profit-seeking commercial business, also play an essential role during an emergency relief process by dispatching urgently-required materials to disaster-affected areas. Therefore, an issue has been widely addressed by logistics practitioners and caught researchers' more attention as to how the logi...