Multilevel mesh partitioning for optimising aspect ratio

Multilevel algorithms are a successful class of optimisation techniques which address the mesh partitioning problem. They usually combine a graph contraction algorithm together with a local optimisation method which refines the partition at each graph level. To date these algorithms have been used almost exclusively to minimise the cut-edge weight, however it has been shown that for certain classes of solution algorithm, the convergence of the solver is strongly influenced by the subdomain aspect ratio. In this paper therefore, we modify the multilevel algorithms in order to optimise a cost function based on aspect ratio. Several variants of the algorithms are tested and shown to provide excellent results.

The Catford Riddim on the 202

This presentation is about a song, ”Catford Riddim” by the A-Team, a group of grime artists from South London, specifically about how it came to be played, perhaps a bit too loudly, in the back of the 202 bus one January morning on a teenager’s mobile phone. As an illustration of how social networks and technological networks converge, the ”Catford Riddim,” insisting on the music’s own provenance from the SE6 postcode, shows the formation of a local ethnoscape in the global networks of peer-to-peer file sharing and online DIY distribution sites such as MySpace. Contesting the narrative of online social networks as routes to fame, I suggest that on the contrary they illustrate the emergence of local, even insular, ”scenes” of musicians, events and audiences.