Discussion summary: Fictitious domain methods

Fictitious Domain methods are constructed in the following manner: Suppose a partial differential equation is to be solved on an open bounded set, Omega, in 2-D or 3-D. Let R be a rectangle domain containing the closure of Omega. The partial differential equation is first solved on R. Using the solution on R, the solution of the equation on Omega is then recovered by some procedure. The advantage of the fictitious domain method is that in many cases the solution of a partial differential equation on a rectangular region is easier to compute than on a nonrectangular region. Fictitious domain methods for solving elliptic PDEs on general regions are also very efficient when used on a parallel computer. The reason is that one can use the many domain decomposition methods that are available for solving the PDE on the fictitious rectangular region. The discussion on fictitious domain methods began with a talk by R. Glowinski in which he gave some examples of a variational approach to ficititious domain methods for solving the Helmholtz and Navier-Stokes equations

Internet Media in Technological Risk Amplification: Plutonium on Board the Cassini-Huygens Spacecraft

The author discusses how the Cassini controversy demonstrates the power of the Internet, particularly listservs and Usenet groups, and how this resource offers political activists an opportunity to affect the agendas of risk management policy decision-makers

Compétitivité canadienne et libre-échange nord-américain : les trois premières années de l’ALÉ

Cet article tente d’établir un bilan de l’évolution des facteurs de compétitivité relative du secteur manufacturier canadien depuis l’entrée en vigueur de l’Accord de libre-échange et évalue les effets structurels qui en ont découlé pour le volume des échanges bilatéraux et multilatéraux.This paper is an attempt to monitor the economic changes that have resulted from changes in Canadian competitiveness as a result of the FTA. The sources of changes in Canadian manufacturing competitiveness and their structural effects on bilateral and multilateral trade flows are identified