A scalable strategy for the parallelization of multiphysics unstructured mesh-iterative codes on distributed-memory systems

Realizing scalable performance on high performance computing systems is not straightforward for single-phenomenon codes (such as computational fluid dynamics [CFD]). This task is magnified considerably when the target software involves the interactions of a range of phenomena that have distinctive solution procedures involving different discretization methods. The problems of addressing the key issues of retaining data integrity and the ordering of the calculation procedures are significant. A strategy for parallelizing this multiphysics family of codes is described for software exploiting finite-volume discretization methods on unstructured meshes using iterative solution procedures. A mesh partitioning-based SPMD approach is used. However, since different variables use distinct discretization schemes, this means that distinct partitions are required; techniques for addressing this issue are described using the mesh-partitioning tool, JOSTLE. In this contribution, the strategy is tested for a variety of test cases under a wide range of conditions (e.g., problem size, number of processors, asynchronous / synchronous communications, etc.) using a variety of strategies for mapping the mesh partition onto the processor topology.

[Conference report] Magic and mathematics: The life and work of John Dee. National Maritime Museum, Greenwich, 13-14 June 2003

Tony Mann provides a report of a two-day meeting "Magic and mathematics: The life and work of John Dee" held from 13-14 June 2003 at the National Maritime Museum, Greenwich.

[Recording review] William Herschel, Symphonies Nos. 2, 8, 12, 13, 14, 17

Tony Mann provides a review of the recording: William Herschel, Symphonies Nos. 2, 8, 12, 13, 14, 17, soloists, London Mozart Players / Matthias Bamert, Chandos 10048, 2003, (68 mins). [CD]

Colloidal microgel in removal of water from biodiesel

A series of poly(N-isopropylacrylamide) [pNIPAM]-based homo-polymer and co-polymer microgel particles were prepared by surfactant-free emulsion polymerisation. The co-monomers were acrylic acid. 4-vinylpyridine. butyl acrylate, 4-vinylbiphenyl and vinyl laurate. Co-monomers were added at a concentration of 10% (w/w) relative to the base monomer pNIPAM for the preparation of each co-polymer microgel. The co-monomers chosen vary by their organic chain length, polarity and pH sensitivity, as these should influence how the particles behave in aqueous and non-aqueous solvents. The effect of adding different types of co-monomer into the microgel structure was investigated with respect to their dispersibility in different solvents. These microgel particles have shown useful application in the removal of water from biodiesel prepared from rape seed. Karl Fischer experiments showed that microgel particles can be used to reduce the water content in biodiesel to an acceptable level for incorporation into internal combustion engines. (C) 2008 Elsevier B.V. All rights reserved.

A new 14+: vocational diplomas and the future of schools, colleges and universities. An educational and campaigning pamphlet

Written in an accessible and campaigning style, this pamphlet affords a valuable context to the introduction of the first group of specialist diplomas for 14 year olds in September 2008. The diplomas are the latest in a line of failed initiatives that have sought to provide vocational ‘alternatives’ for those young people staying in full-time education and not considered ‘academic’. Rather than developing any useful employment skills, Allen and Ainley argue that their introduction reflects the changing significance of education in the division and social control of learners that now extends from school to college and on to university. Those who are opposed to the current post-14 agenda, must not only put forward radical alternatives to the current curriculum offer but also, the authors argue, address issues of democracy and accountability. To do this, teacher trade unionists must make new types of alliances with local communities and also with their students.