Dynamic features of the recently introduced extremal optimization heuristic are analyzed. Numerical studies of this evolutionary search heuristic show that it performs optimally at a transition between a jammed and an diffusive state. Using a simple, annealed model, some of the key features of extremal optimization are explained. In particular, it is verified that the dynamics of local search p...

You are going to Paul’s party tonight. You have a long day of work ahead of you before that, but you can’t wait to get there. Your annoying friend comes up to you and says, ‘Hi! Oh, are you going to Paul’s party tonight? I don’t think I’ll go. Unless your going?’ You reply, ‘I have to work.’ There are lies and then there are misleading utterances that are not lies. You did not lie to your frien...

THIS conclusion has led the Royal Commission to recommend doubling the existing numbers of doctors within the next 30 years. This is an expensive proposal that is likely to add many millions of pounds to the annual budget of the nation. It requires careful examination. Estimates of medical manpower requirements are fraught with difficulties and hazards. The proposals of the Willink Committee (1...

Very few information repositories, especially corporate memories, are formal knowledge bases (KBs) since, despite its benefits, formal and scalable knowledge modelling is inherently a difficult and time-consuming exercise that current generic KB systems (KBSs) still do not guide well. Instead, repositories are most often composed of informal documents that are independently created by people (t...

The Levitron TM is a magnetic spinning top which can levitate in the constant eld of a repelling base magnet. An explanation for the stability of the Levitron TM using adiabatic approximation has been given by M.V. Berry. In experiment the top eventually looses stability at a critical spin rate which can not be predicted by Berry's approach. The present work develops an exact theory of the Levi...