The aim of this paper is to study continuum models for surface diffusion taking into account free adatoms on the surface, which is of particular importance in the (self-assembled) growth of nanostructures. The extended model yields a coupled system of parabolic differential equations for the surface morphology and the adatom density, involving a cross-diffusion structure. We investigate two dif...

We show that it is possible, for every machine universal for Kolmogorov complexity, to enumerate the lexicographically least description of a length n string in O(n) attempts. In contrast to this positive result for strings, we find that, in any Kolmogorov numbering, no enumerator of nontrivial size can generate a list containing the minimal index of a given partial-computable function. One can...

In this paper new methodologies for clustering and dimensionality reduction of large data sets are illustrated using both a least-squares and maximum likelihood approach. The methodologies are described by both real applications and Monte Carlo simulations.

How do we include animals in sociology? Although sociology’s initial avoidance of the nonhuman world may have been necessary to field’s development, recent scholarship – within mainstream sociology, environmental sociology and animal-centred research is helping expand horizons. With a focus on variety, this article reviews four key paths that researchers are taking their research: (1) studying ...

The mobility of chemicals released into the environment governs their bioavailability to organisms and their partitioning between environmental compartments, and thus represents a direct link between environmental pollution and ecotoxicity. The microand mesoscale transport processes involved are related to the properties of the chemicals themselves, but also to environmental compartments. Thus,...