In this paper novel reflectarray antenna elements are proposed using aperture-coupled dielectric resonator antenna structures. Using these new structures, wide phase range and wide frequency bandwidth (up to 28.5%) with parallel and linear phase curves are obtained. In each case, an array consisting of 289 elements was simulated using the finite integration technique (FIT). The arrays exhibit 3...

In the given paper, we confront three finite difference approximations to the Navier–Stokes equations for the two-dimensional viscous incomressible fluid flows. Two of these approximations were generated by the computer algebra assisted method proposed based on the finite volume method, numerical integration, and difference elimination. The third approximation was derived by the standard replac...

Most of our work was implemented using Python scripts; we used CrankNicolson finite difference schemes, second order accurate in space, first order in the time-like sense. The velocity field within the test apparatus was produced by D'Arcy et al using the commercial CFD code Fluent. LPA and Verlet integration schemes were used to calculate the motion of a particle through the USP velocity field...

A new resistance simulator for extraction of the parasitic parameters from VLSI layout is presented. The calculation of resistor network is based on the boundary element method (BEM). The computational results indicate that the BEM has an advantage over the finite difference method (FDM) and the finite element method (FEM). Since only discretized equations on the boundary of solved domain need ...

We consider the numerical integration of the Degasperis–Procesi equation, which was recently introduced as a completely integrable shallow water equation. For the equation, we propose nonlinear and linear finite difference schemes that preserve two invariants associated with the bi-Hamiltonian form of the equation at a same time. We also prove the unique solvability of the schemes, and show som...

Two new finite difference schemes based on the method of characteristics are presented for convection-diffusion problems. Both of the schemes are of second order in time, and the matrices of the derived systems of linear equations are symmetric. No numerical integration is required for them. The one is of first order in space and the other is of second order. For the former scheme, an optimal e...

• Table S6: Harmonic vibrational frequencies at the ωB97X-D/aug-cc-pVTZ level using SG-2 and SG-3. In this case, analytic Hessians are available in QChem so we compare these analytic results to frequencies computed via finite difference of analytic gradients. Results show that there is very little difference between the two approaches, which validates other finite-difference frequencies reporte...

the bem is applied to the solution of the torsion problem of non-homogeneous anisotropic non-circular prismatic bars. the problem is formulated in terms of the warping function. this formulation leads to a second order partial differential equation with variable coefficients, subjected to a generalized neumann type boundary condition. the problem is solved using the analog equation method (aem)...