E.K. Gibson, Jr., S.J. Clemett, K.L. Thomas-Keprta, D.S. McKay, S.J. Wentworth, F. Robert, A.B. Verchovsky, I.P. Wright, C.T.Pillinger, T. Rice and B. Van Leer; KR, ARES, NASA-JSC, Houston, TX 77058; ESCG, Mail Code JE23, Johnson Space Center, Houston, TX 77058; LEME, CNRS-Museum D’Histoire Naturelle, Paris, France; PSSRI, The Open University, Milton Keynes, MK7 6AA, UK, FEI Company, Hillsboro,...

In this paper we demonstrate the performance of a slope limiting procedure combined with a discontinuous Galerkin (DG) finite element solver for 2D compressible Euler equations. The slope limiter can be categorized into van Albada type and is differentiable. This slope limiter is modified from a similar limiter used in finite volume solvers to suit the needs of the DG solver. The gradient in an...

The Harten–Lax–van Leer scheme is popularly used in the CFD community. However, oscillations are observed from shock tube problems for stiffened gases when the adiabatic index is greater than 3. To understand this phenomenon, the dissipation effect of the scheme is evaluated quantitatively in terms of dissipation matrices. We have proven and numerically demonstrated that lack of positive defini...

Hierdie artikel bespreek die agtergrond van opvoedkundige tegnologie en die trefkrag daarvan op alle fasette van die onderwys. Daar word definisies gegee van “ opvoedkundige tegnologie” in die ruim ste sin van die woord en ook van opvoedkundige tegnoloé. B loom se taksonom ie van opvoedkundige doelstellings op die kognitiew e en affektiew e terreine word met betrekking tot die ontwikkeling van ...