12,789 research outputs found
Factorization properties of genus-two bosonic and fermionic string partition functions
The genus-two bosonic and fermionic string partition functions factorize, in the separating pinching limit, into genus-one partition functions after integrating out the supermoduli with super-Beltrami support on the puncture points in the fermionic and heterotic case
Wind and solar powered turbine
A power generating station having a generator driven by solar heat assisted ambient wind is described. A first plurality of radially extendng air passages direct ambient wind to a radial flow wind turbine disposed in a centrally located opening in a substantially disc-shaped structure. A solar radiation collecting surface having black bodies is disposed above the fist plurality of air passages and in communication with a second plurality of radial air passages. A cover plate enclosing the second plurality of radial air passages is transparent so as to permit solar radiation to effectively reach the black bodies. The second plurality of air passages direct ambient wind and thermal updrafts generated by the black bodies to an axial flow turbine. The rotating shaft of the turbines drive the generator. The solar and wind drien power generating system operates in electrical cogeneration mode with a fuel powered prime mover
Road user charging and implications for transport policy: Findings from the CURACAO project
This paper reports on the outcomes of a European project, CURACAO, designed to support the implementation of urban road user charging (URUC) as a demand management tool in urban areas. The project did this through engagement with a User Group of cities interested in pursuing URUC to identify the barriers preventing them from doing so.
The project reviewed the complete process of setting up a URUC scheme from the setting of objectives, through to scheme design, predicting impacts, achieving acceptability and the implementation process and presented its findings in a State of the Art Report and a Case Studies Report. The State of the Art Report provides evidence collated from research and practice to address a series of 14 themes identified by the User Group, including objectives; scheme design; technology; business systems; prediction; traffic, environmental, economic and equity impacts; appraisal; acceptability; transferability; implementation; and evaluation. The Case Study Report reviewed 16 proposed or implemented schemes in Europe, focusing on pricing objectives, scheme design, the implementation process and scheme results. On this basis, the CURACAO Consortium developed a list of policy recommendations aimed at cities and regional authorities, national governments, and the European Commission.
The paper summarises the main findings of the State of the Art Report and the case studies. On this basis, it outlines the policy recommendations which were drawn, and identifies future research needs
Occupational health for an ageing workforce: Do we need a geriatric perspective?
10.1186/1745-6673-1-8Journal of Occupational Medicine and Toxicology11
Evaluation of the utility of sediment data in NASQAN (National Stream Quality Accounting Network)
Monthly suspended sediment discharge measurements, made by the USGS as part of the National Stream Quality Accounting Network (NASQAN), are analysed to assess the adequacy in terms of spatial coverage, temporal sampling frequency, accuracy of measurements, as well as in determining the sediment yield in the nation's rivers.
It is concluded that the spatial distribution of NASQAN stations is reasonable but necessarily judgemental. The temporal variations of sediment data contain much higher frequencies than monthly. Sampling error is found to be minor when compared with other causes of data scatter which can be substantial. The usefulness of the monthly measurements of sediment transport is enhanced when combined with the daily measurements of water discharge. Increasing the sampling frequency moderately would not materially improve the accuracy of sediment yield determinations
Chain configurations in light nuclei
The model of nuclear matter built from alpha-particles is proposed. The
strong deformed shape for doubly even N=Z nuclides from carbon to magnesium has
been determined according to this model. In this paper we undertake very simple
approach, which assumes the existence of low lying chain configurations.Comment: 6 pages, 5 figure
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