It has long been known that a simple rigid pendulum can be stabilized against small disturbances in its upside-down state by rapid vertical oscillations of its pivot. Over part of the parameter range for which this happens we find that there is a second, quite different way in which the pendulum can avoid falling over, namely by getting trapped in a limit cycle oscillation about the upward vert...

Biological motion observation has been recognized to produce dynamic change in sensorimotor activation according to the observed kinematics. Physical plausibility of the spatial-kinematic relationship of human movement may play a major role in the top-down processing of human motion recognition. Here, we investigated the time course of scalp activation during observation of human gait in order ...

Abstract—Local irregular topography has a great impact on earthquake ground motion. For scarp topography, using numerical simulation method, the influence extent and scope of the scarp terrain on scarp's upside and downside ground motion are discussed in case of different vertical incident SV waves. The results show that: (1) The amplification factor of scarp's upside region is greater than tha...

Over the recent years, several proposals were made to enhance database systems with automated reasoning. In this article we analyze two such enhancements based on meta-interpretation. We consider on the one hand the theorem prover Satchmo, on the other hand the Alexander and Magic Set methods. Although they achieve different goals and are based on distinct reasoning paradigms, Satchmo and the A...

Abstract Knaster-Tarski’s theorem, characterising the greatest fix- point of a monotone function over complete lattice as largest post-fixpoint, naturally leads to so-called coinduction proof principle for showing that some element is below fixpoint (e.g., providing bisimilarity witnesses). The dual principle, used an above least fixpoint, related inductive invariants. In this paper we provide ...

Are slackers a drag on the rest of us? It makes sense because those who produce (‘‘co-operators’’) benefit everyone, whereas those who don’t produce (‘‘cheats’’) get a free ride. In yeast, for instance, most strains are co-operators, secreting an enzyme called invertase that converts sucrose into the more efficiently metabolized glucose. However, about a tenth of strains are cheats that do not ...