Unearthing the roots of urban sprawl: a critical analysis of form, function and methodology

Urban sprawl is one of the key issues facing cities today. There is a large volume of literature on the topic but despite this there is little agreement as to its characteristics and effects. The paper discusses some of the most contested issues of urban sprawl. It looks at the various definitions of sprawl; examines the effects of sprawl, assessing these in relation to planning and market led approaches; and discusses methodological approaches relating to measures of sprawl in terms of its impacts and forms

Dynamical Multiple-Timestepping Methods for Overcoming the Half-Period Time Step Barrier

Current molecular dynamic simulations of biomolecules using multiple time steps to update the slowingly changing force are hampered by an instability occuring at time step equal to half the period of the fastest vibrating mode. This has became a critical barrier preventing the long time simulation of biomolecular dynamics. Attemps to tame this instability by altering the slowly changing force and efforts to damp out this instability by Langevin dynamics do not address the fundamental cause of this instability. In this work, we trace the instability to the non-analytic character of the underlying spectrum and show that a correct splitting of the Hamiltonian, which render the spectrum analytic, restores stability. The resulting Hamiltonian dictates that in additional to updating the momentum due to the slowly changing force, one must also update the position with a modified mass. Thus multiple-timestepping must be done dynamically.Comment: 10 pages, 2 figures, submitted to J. Chem. Phy

Outdoor recreation resources in the Manawatu : with a preliminary case study of Foxton Beach as a water-based recreation resource

The subject of supply of outdoor recreation resources is discussed in this thesis. The nature of the resources suitable for outdoor recreation and the present use made of them are determined. The extent and use of one type of recreation resource in the Manawatu - the Water-based recreation resource - is extensively reviewed. A preliminary case study is made of Foxton Beach as a water - based recreation environment. The results of the study of the ecological implications of recreation on the beach and the visitor surveys conducted there are presented. Major areas of 'ecological intolerance' are described and the recreation behaviours exhibited by the visitors at the beach are reported. Foxton Beach is reported to be able to attract visitors from within and outside the Manawatu region

High-order Path Integral Monte Carlo methods for solving quantum dot problems

The conventional second-order Path Integral Monte Carlo method is plagued with the sign problem in solving many-fermion systems. This is due to the large number of anti-symmetric free fermion propagators that are needed to extract the ground state wave function at large imaginary time. In this work, we show that optimized fourth-order Path Integral Monte Carlo methods, which use no more than 5 free-fermion propagators, can yield accurate quantum dot energies for up to 20 polarized electrons with the use of the Hamiltonian energy estimator.Comment: 14 pages, 4 figures, submitted to PRE - revised with a new figure and added larger N calculation