11,512 research outputs found
Tackling barriers to take-up of fuel poverty alleviation measures
Although there has been much work around the take-up of fuel poverty alleviation programmes carried out this has generally focussed on evidence from frontline managers and other stakeholders. Any investigation with end users has been minimal. Funded by Eaga Partnership Charitable Trust, Sustainable Cities Research Institute carried out a community-based investigation into barriers and possible solutions to the uptake of fuel poverty alleviation programmes. A combination of desk-based research with frontline staff and Participatory Appraisal (PA) techniques with communities were used to carry out this research. 362 people took part in the PA and 17 frontline staff returned detailed questionnaires. 4 areas were studied: 3 with poor and one with good take-up. Additionally vulnerable groups of consumers were identified; elderly, Black and Minority Ethnic (BME) groups and rural consumers. Each of the 3 areas with poor take-up has a good concentration of one of the identified vulnerable groups
Many-body approach to infinite non-periodic systems: application to the surface of semi-infinite jellium
A method to implement the many-body Green function formalism in the GW
approximation for infinite non periodic systems is presented. It is suitable to
treat systems of known ``asymptotic'' properties which enter as boundary
conditions, while the effects of the lower symmetry are restricted to regions
of finite volume. For example, it can be applied to surfaces or localized
impurities. We illustrate the method with a study of the surface of
semi-infinite jellium. We report the dielectric function, the effective
potential and the electronic self-energy discussing the effects produced by the
screening and by the charge density profile near the surface.Comment: 11 pages, 4 figure
Changes of partitioning and increased root lengths of spruce and beech exposed to ambient pollution concentrations in southern England
International audienc
Compensating for Missing Data from Longitudinal Studies Using WinBUGS
Missing data is a common problem in survey based research. There are many packages that compensate for missing data but few can easily compensate for missing longitudinal data. WinBUGS compensates for missing data using multiple imputation, and is able to incorporate longitudinal structure using random effects. We demonstrate the superiority of longitudinal imputation over cross-sectional imputation using WinBUGS. We use example data from the Australian Longitudinal Study on Women's Health. We give a SAS macro that uses WinBUGS to analyze longitudinal models with missing covariate date, and demonstrate its use in a longitudinal study of terminal cancer patients and their carers.
Kohn-Sham Exchange Potential for a Metallic Surface
The behavior of the surface barrier that forms at the metal-vacuum interface
is important for several fields of surface science. Within the Density
Functional Theory framework, this surface barrier has two non-trivial
components: exchange and correlation. Exact results are provided for the
exchange component, for a jellium metal-vacuum interface, in a slab geometry.
The Kohn-Sham exact-exchange potential has been generated by using
the Optimized Effective Potential method, through an accurate numerical
solution, imposing the correct boundary condition. It has been proved
analytically, and confirmed numerically, that ; this conclusion is not affected by the inclusion of correlation
effects. Also, the exact-exchange potential develops a shoulder-like structure
close to the interface, on the vacuum side. The issue of the classical image
potential is discussed.Comment: Phys. Rev. Lett. (to appear
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