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Abstract:The utilisation of accessibility potential models is widespread in geographical studies of transport. A problem emerges, however, when these models are applied in that their interpretations and results may result in some difficulties and ambiguity. In order to eliminate this problem, we have developed a method which is convenient for breaking down the accessibility potentials into four univocal elements. This article analyses the features of these factors and the interrelationships of their spatial development patterns by using the example of the EU NUTS3 regions.

A number of mechanisms are explored for modelling equilibrium values of attractiveness terms in production-constrained spatial-interaction models. They include revenue and facility-size balancing, a differential-equation representation of profit maximisation, and mathematical-programming formulations. The different methods turn out to be closely related but offer different and complementary insights. Some dynamic properties of such equilibrium points are explored, including the identification of circumstances which generate discrete changes for smooth changes in parameters. A number of possible algorithms for calculating the points are described.

In August 2011, several areas of London experienced episodes of large-scale disorder, comprising looting, rioting and violence. Much subsequent discourse has questioned the adequacy of the police response, in terms of the resources available and strategies used. In this article, we present a mathematical model of the spatial development of the disorder, which can be used to examine the effect of varying policing arrangements. The model is capable of simulating the general emergent patterns of the events and focusses on three fundamental aspects: the apparently-contagious nature of participation; the distances travelled to riot locations; and the deterrent effect of policing. We demonstrate that the spatial configuration of London places some areas at naturally higher risk than others, highlighting the importance of spatial considerations when planning for such events. We also investigate the consequences of varying police numbers and reaction time, which has the potential to guide policy in this area.

It is shown that Boltzmann's methods from statistical physics can be applied to a much wider range of systems, and in a variety of disciplines, than has been commonly recognized. A similar argument can be applied to the ecological models of Lotka and Volterra. Furthermore, it is shown that the two methodologies can be applied in combination to generate the Boltzmann, Lotka and Volterra (BLV) models. These techniques enable both spatial interaction and spatial structural evolution to be modelled, and it is argued that they potentially provide a much richer modelling methodology than that currently used in the analysis of 'scale-free' networks.