A Multiple Criteria Decision Modelling approach to selection of estimation techniques for fitting extreme floods

The problem of fitting a probability distribution, here log-Pearson Type III distribution, to extreme floods is considered from the point of view of two numerical and three non-numerical criteria. The six techniques of fitting considered include classical techniques (maximum likelihood, moments of logarithms of flows) and new methods such as mixed moments and the generalized method of moments developed by two of the co-authors. The latter method consists of fitting the distribution using moments of different order, in particular the SAM method (Sundry Averages Method) uses the moments of order 0 (geometric mean), 1 (arithmetic mean), –1 (harmonic mean) and leads to a smaller variance of the parameters. The criteria used to select the method of parameter estimation are:

Sounding the dark cosmos

Bruce Bassett, Bob Nichol and Daniel J Eisenstein explain why the Wide-Field Multi-Object Spectrograph will need to look so far into the universe, over such a wide area, in order to map sound waves from the dawn of time.     

Cultural political economy: On making the cultural turn without falling into soft economic sociology

This article explores the implications of making the cultural turn in the engagement of economic and political geography with issues of political economy. It seeks to steer a path between a fetishistic, reified economics that naturalizes economic categories and a soft economic sociology that focuses on the similarities between economic and other socio-cultural activities at the expense of the specificity of the economic. We show how combining critical semiotic analysis with an evolutionary and institutional approach to political economy offers one interesting way to achieve this goal. An evolutionary and institutional approach to semiosis enables us to recognize the semiotic dimensions of political economy at the same time as establishing how and why only some economic imaginaries among the many that circulate actually come to be selected and institutionalized; and Marxian political economy enables us to identify the contradictions and conflicts that make capital accumulation inherently improbable and crisis-prone, creating the space for economic imaginaries to play a role in stabilizing accumulation in specific spatio-temporal fixes and/or pointing the way forward from recurrent crises. The paper illustrates these arguments with a case study on the Flemish ‘anchoring strategy’ as a specific regional economic development strategy. It concludes with a set of guidelines for the further development of cultural political economy.     

Aligned olivine in the Springwater pallasite

The mechanism by which olivine grains became embedded within iron‐nickel alloy in pallasite meteorites continues to be a matter of scientific debate. Geochemical and textural observations have failed to fully elucidate the origin and history of the olivine crystals; however, little research attention has been devoted to their crystallographic orientations within the metal matrix. Using electron backscatter diffraction, we have collected crystallographic orientation data for 296 crystals within ～65 cm² sample surface from Springwater. Though no global crystallographic preferred orientation exists, very low misorientations are observed among [100] axes of olivine crystals within specific texturally defined domains. Combined with a thorough characterization of large‐scale Springwater textures, the definitively nonrandom spatial distribution of olivine orientations provides clues regarding the nature of the olivine's initial formation environment as well as the sequence of events subsequent to metal incorporation.     

Australian conservation organisations' perspectives on tourism in national parks: a critique

Australia's conservation and parks organisations have become actively involved in the debate over tourism use of national parks and their associated wilderness areas. To date, at least seven organisations have produced at least ten formal policy statements and submissions. This paper presents an analysis of these policy statements.The policies reviewed use a narrow definition of tourism, based on the presence or absence of commercial, private sector activity. If commercial activity exists, then tourism exists; if not, then it is considered to be recreation. This distinction reflects the widely held opinion among many environmentalists that non-commercial use of national parks is acceptable, but that commercial use is essentially unacceptable, even though the groups may be participating in the same activity. The author argues that while making a number of valuable suggestions, these policies suffer from major conceptual flaws that minimise their contribution to the debate on acceptable human uses of parks.The author concludes by making a number of recommendations to rectify the conceptual flaws inherent in the policies.     

Rural women and technology in South Africa: Case studies from KwaZulu-Natal Province

This article contributes to a greater understanding of the linkages between women's roles, responsibilities and their use of technology in poor rural communities. The ways in which poor rural women conceptualize technology is examined. Furthermore, how they use their knowledge and skills to develop, modify and adapt the techniques and technical processes in which they are involved are also explored. Additionally, the links between indigenous and modern technologies in relation to gender considerations in poor rural contexts are examined. This article draws from findings of primary research undertaken in two marginalized rural communities in Kwazulu-Natal, South Africa. The study reveals that the use of technologies are highly gendered and differentiated among women. Poor rural women utilize a range of technologies in both productive and reproductive activities which are central to their livelihood strategies, especially at the household level. Furthermore, although women are adapting and innovating technologies their expertise remains largely unrecognized. A range of problems and constraints exist which limit women's access to and use of technologies. A key tension identified in the study is that between the use of locally-based, indigenous technologies and modern, external technologies. This revised version was published online in July 2006 with corrections to the Cover Date.     

Aggregate settling velocity of combined sewage overflow

In order to better model the fate and transport of material in a combined sewer overflow (CSO), hydrologic and geochemical measurements were made during a storm event in Flushing Bay, NY, USA. Particle size, total suspended solids concentrations, and CSO solid density are used to calculate the settling velocity of aggregates of the CSO material. Roughly half of the material that is discharged from the outfall sinks rapidly to the bottom, while the other half forms a turbid surface plume in fresher water. The dry solid density of the CSO material was 1589 kg m(-3) and the volume fraction of solid material to total aggregate volume ranged from 0.1 to 1.0. The settling velocity estimates of aggregated material in the surface plume ranged from about 0.5 to 9.0 mm s(-1) with a median settling velocity of 2.9 mm s(-1). A strong inverse relationship between the size of the aggregates and the aggregate density resulted in a fractal dimension of the aggregates of 2.3.     

Relativistic charged particle precipitation into Jupiter's sub-auroral atmosphere

Longitudinal variations of energetic charged particle precipitation into the jovian sub-auroral atmosphere are modeled based on weak diffusion scattering and variations in the local loss-cone size associated with asymmetries in the VIP-4 magnetic field model. Our scattering model solutions suggest that low latitude observations of enhanced H₃⁺ and X-ray emissions are at least partially due to precipitating energetic particles. The correlation between model results and observations is best in the northern hemisphere at low L (1.5), where the surface magnetic field variation is largest and observations have the highest resolution. Weaker correlations in the southern hemisphere and at higher latitudes, particularly for H₃⁺ emissions, are likely due to the presence of other energy sources, lack of resolution in the observations and limitations in the sub-auroral surface magnetic field model.     

Retrospective multivariate Bayesian change-point analysis: A simultaneous single change in the mean of several hydrological sequences

Although hydrological time series for different sites in a given region are usually correlated and that climate changes should have a regional impact on water resources, very little has appeared in the literature about multivariate change-point analysis. This paper generalizes the univariate Bayesian approach for the detection of a single shift in the mean level to study a change in the mean-vector of a sequence of multivariate normal vectors. Two different problems are considered: the first one is the estimation of the unknown regional change-point under the hypothesis that a shift occurred, while the second one is the overall assessment of change versus no change. This method is illustrated by an application to streamflow data series for six rivers situated in the Northern Québec Labrador region.