The effects of gravity stabilization and destabilization on the slow displacement of a wetting fluid by a non-wetting fluid in two-dimensional and three-dimensional porous media have been investigated experimentally. The characteristic features of the resulting displacement patterns can be...

In this paper we present empirical results based on a network model for commuting flows. The model is a modified version of a construction introduced in Thorsen et al. (1999). Journeys-to-work are determined by distance deterrence effects, the effects of intervening opportunities, and the...

In this paper we propose a modified gravity model that takes into account that a population generally consists of heterogeneous groups, and we suggest a new statistical test for heterogeneity. We apply our new model to two real world data sets, and it turns out that this new model fits the data...

In many cases fjords cause disconnections in the road network, calling for the service of ferries. The construction of bridges or subsea tunnels may, however, substitute the ferries, often financed by toll charges. In this paper we use data on commuting flows from a Norwegian region with a high...

We derive general properties of the finite-size scaling of probability density functions and show that when the apparent exponent <InlineEquation ID="Equ1"> <EquationSource Format="TEX">$\tilde{\tau}$</EquationSource> </InlineEquation> of a probability density is less than 1, the associated finite-size scaling ansatz has a scaling exponent τ equal to 1, provided that the fraction...</equationsource></inlineequation>