The effect of some environmental factors on rapid mass movement in the Hunua Ranges, New Zealand

This paper describes some of the relationships between rapid mass movement and environmental factors in the Hunua Ranges. Extreme climatic events appear to be important in triggering mass movement, while vegetation has a marked effect on mass movement processes and resulting landforms. The main effects of lithology and soils are connected with their influence on site conditions of mass movement. Drainage basin morphometry is affected by the addition of channels produced by mass movement

Benford's law and complex atomic spectra

We found that in transition arrays of complex atomic spectra, the strengths of electric-dipolar lines obey Benford's law, which means that their significant digits follow a logarithmic distribution favoring the smallest values. This indicates that atomic processes result from the superposition of uncorrelated probability laws and that the occurrence of digits reflects the constraints induced by the selection rules. Furthermore, Benford's law can be a useful test of theoretical spectroscopic models. Its applicability to the statistics of electric-dipolar lines can be understood in the framework of random matrix theory and is consistent with the Porter-Thomas law.Comment: 7 pages, 2 figures. submitted to Physical Review

Resistivity in warm dense plasmas beyond the average-atom model

The exploration of atomic properties of strongly coupled partially degenerate plasmas, also referred to as warm dense matter, is important in astrophysics, since this thermodynamic regime is encountered for instance in Jovian planets' interior. One of the most important issues is the need for accurate equations of state and transport coefficients. The Ziman formula has been widely used for the computation of the static (DC) electrical resistivity. Usually, the calculations are based on the continuum wavefunctions computed in the temperature and density-dependent self-consistent potential of a fictive atom, representing the average ionization state of the plasma (average-atom model). We present calculations of the electrical resistivity of a plasma based on the superconfiguration (SC) formalism. In this modeling, the contributions of all the electronic configurations are taken into account. It is possible to obtain all the situations between the two limiting cases: detailed configurations (a super-orbital is a single orbital) and detailed ions (all orbitals are gathered in the same super-orbital). The ingredients necessary for the calculation are computed in a self-consistent manner for each SC, using a density-functional description of the electrons. Electron exchange-correlation is handled in the local-density approximation. The momentum transfer cross-sections are calculated by using the phase shifts of the continuum electron wavefunctions computed, in the potential of each SC, by the Schroedinger equation with relativistic corrections (Pauli approximation). Comparisons with experimental data are also presented.Comment: submitted to "Contributions to Plasma Physics

A Fairytale Ending Or The Same Old Story? The New Economy and Economic Growth in the United States.

This paper uses a production function approach to put the recent contribution of the New Economy to US economic growth into perspective by undertaking an analysis of the sources of technical progress in the business sector over the post-war period. We model jointly a pair of factor demand equations derived consistently from an underlying CES production technology, and explicitly endogenise technical progress. Knowledge accumulation via R&D and education are found to be the main sources of technical progress, but there is evidence of significant structural change after 1995 which can be removed by allowing for externalities from investment in information processing equipment and software. Labour augmenting technical progress is estimated to be over 2 per cent per annum faster since 1995 than can otherwise be explained.