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Effective use of data in waste strategy planning in the UK
Effective waste strategy planning for sustainable and integrated waste management is predicated on high-quality information. However a review of recent local authority waste strategies in England, part of a research project into effective use of data and analysis in waste strategy planning carried out by researchers at the Open University, showed little evidence of being based on thorough analysis. Lack of good data on many aspects of performance restricts what can be achieved in planning better integrated, more sustainable waste management provision. This paper draws from the results of that project and illustrates improvements that could be achieved by using better quality data and analysis to inform decision making. The research explored the use of various types of information and analysis including compositional analysis and establishing diversion rates; scenario building; applications of geographical information systems; understanding and measuring public participation; the use of trials to collect relevant data; and understanding of the effects of recycling schemes on residual waste composition. The general principals and methodologies of each approach are illustrated by examples derived from the authors’ analysis and interpretation of local authority data provided by case study partners, and show how local data can provide relevant and effective local answers
Observations of clustering inside oceanic bubble clouds and the effect on short-range acoustic propagation
It has recently been shown [Weber, T. C. et al. (Year: 2007). “Acoustic propagation through clustered bubble clouds,” IEEE J. Ocean. Eng.32, 513–523] that gas bubble clustering plays a role in determining the acoustic field characteristics of bubbly fluids. In particular, it has been shown that clustering changes the bubble-induced attenuation as well as the ping-to-ping variability in the acoustic field. The degree to which bubble clustering exists in nature, however, is unknown. This paper describes a method for quantifying bubble clustering using a high frequency (400kHz) multibeam sonar, and reports on observations of near-surface bubbleclustering during a storm ( 14.6m∕s wind speed) in the Gulf of Maine. The multibeam sonardata are analyzed to estimate the pair correlation function, a measure of bubble clustering. In order to account for clustering in the mean acoustic field, a modification to the effective mediumwave number is made. With this modification, the multibeam sonar observations are used to predict the effect of clustering on the attenuation of the mean field for short-range propagation (1 m) at frequencies between 10 and 350kHz . Results for this specific case show that clusteringcan cause the attenuation to change by 20%–80% over this frequency range
A revision of Pediacus Shuckard (Coleoptera: Cucujidae) for America north of Mexico : with notes on other species
The genus Pediacus Shuckard is revised for America north of Mexico. Seven species are recorded: P. andrewsi Thomas, n. sp.; P. fuscus Erichson; P. gracilis Thomas, n. sp.; P. hesperoglaber Thomas, n. sp.; P. ommatodon Thomas, n. sp.; P. stephani Thomas, n. sp.; and P. subglaber LeConte, new status. The species are described and illustrated, and a key is presented for their identification. The described European and Neotropical species are reviewed and illustrated
On Gaussian Random Supergravity
We study the distribution of metastable vacua and the likelihood of slow roll
inflation in high dimensional random landscapes. We consider two examples of
landscapes: a Gaussian random potential and an effective supergravity potential
defined via a Gaussian random superpotential and a trivial K\"ahler potential.
To examine these landscapes we introduce a random matrix model that describes
the correlations between various derivatives and we propose an efficient
algorithm that allows for a numerical study of high dimensional random fields.
Using these novel tools, we find that the vast majority of metastable critical
points in dimensional random supergravities are either approximately
supersymmetric with or supersymmetric. Such
approximately supersymmetric points are dynamical attractors in the landscape
and the probability that a randomly chosen critical point is metastable scales
as . We argue that random supergravities lead to potentially
interesting inflationary dynamics.Comment: 36 pages, 9 figure
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