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A thermally stable tension meter for atmospheric soundings using kites
Kites offer considerable potential as wind speed sensorsāa role distinct from their traditional use
as instrument-carrying platforms. In the sensor role, wind speed is measured by kite-line tension. A
kite tether line tension meter is described here, using strain gauges mounted on an aluminum ring
in a Wheatstone bridge electronic circuit. It exhibits a linear response to tension 19.5 mV Nā1
with good thermal stability mean drift of ā0.18 N Ā°Cā1 over 5ā45 Ā°C temperature range and a
rapid time response 0.2 s or better. Field comparisons of tether line tension for a Rokkaku kite with
a fixed tower sonic anemometer show an approximately linear tension-wind speed relationship over
the range 1ā6 msā1. Ā© 2010 American Institute of Physics. doi:10.1063/1.346556
Assessment of the environmental toxicity and carcinogenicity of tungsten-based shot.
The toxicity of elemental tungsten released from discharged shot was assessed against previous studies that established a 1% toxic threshold for soil organisms. Extremely heavy theoretical shot loadings of 69,000 shot/ha were used to generate estimated environmental concentrations (EEC) for two brands of tungsten-based shot containing 51% and 95% tungsten. The corresponding tungsten EEC values were 6.5ā13.5 mg W/kg soil, far below the 1% toxic threshold. The same shot loading in water produced tungsten EEC values of 2.1ā4.4 mg W/L, levels that are not toxic under experimental conditions. Pure tungsten has not been shown to exhibit carcinogenic properties when ingested or embedded in animal tissues, but nickel, with which it is often alloyed, has known carcinogenicity. Given the large number of waterfowl that carry shot embedded in their body, it is advisable to screen lead shot substitutes for their carcinogenic potential through intra-muscular implantation
Clear air turbulence
Research on forecasting, detection, and incidents of clear air turbulenc
Science requirements for a global change technology architecture trade study
Science requirements for a global change technology initiative (GCTI) Architecture Trade Study were established by reviewing and synthesizing results from recent studies. A scientific rationale was adopted and used to identify a comprehensive set of measureables and their priorities. Spatial and temporal requirements for a number of measurement parameters were evaluated based on results from several working group studies. Science requirements were defined using these study results in conjunction with the guidelines for investigating global changes over a time scale of decades to centuries. Requirements are given separately for global studies and regional process studies. For global studies, temporal requirements are for sampling every 1 to 12 hours for atmospheric and radiation parameters and 1 day or more for most earth surface measurements. Therefore, the atmospheric measureables provide the most critical drivers for temporal sampling. Spatial sampling requirements vary from 1 km for land and ocean surface characteristics to 50 km for some atmospheric parameters. Thus, the land and ocean surface parameters have the more significant spatial variations and provide the most challenging spatial sampling requirements
Particle-in-cell simulations of collisionless magnetic reconnection with a non-uniform guide field
Results are presented of a first study of collisionless magnetic reconnection starting from a recently found exact nonlinear force-free VlasovāMaxwell equilibrium. The initial state has a Harris sheet magnetic field profile in one direction and a non-uniform guide field in a second direction, resulting in a spatially constant magnetic field strength as well as a constant initial plasma density and plasma pressure. It is found that the reconnection process initially resembles guide field reconnection, but that a gradual transition to anti-parallel reconnection happens as the system evolves. The time evolution of a number of plasma parameters is investigated, and the results are compared with simulations starting from a Harris sheet equilibrium and a Harris sheet plus constant guide field equilibrium
Different intra- and inter-molecular hydrogen-bonding patterns in (3S,4aS,8aS)-2-[(2R,3S)-3-(2,5-X2-benzamido)-2-(2,5-X2-benzo-yloxy)-4-phenyl-butyl]-N-tert-butyldeca-hydro-iso-quinoline-3-carboxamides (X = H or Cl) : compounds with moderate aspartyl protease inhibition activity
We thank the EPSRC National Crystallography Service (University of Southampton) for the X-ray data collections.Peer reviewedPublisher PD
Some remarks on one-dimensional force-free Vlasov-Maxwell equilibria
The conditions for the existence of force-free non-relativistic
translationally invariant one-dimensional (1D) Vlasov-Maxwell (VM) equilibria
are investigated using general properties of the 1D VM equilibrium problem. As
has been shown before, the 1D VM equilibrium equations are equivalent to the
motion of a pseudo-particle in a conservative pseudo-potential, with the
pseudo-potential being proportional to one of the diagonal components of the
plasma pressure tensor. The basic equations are here derived in a different way
to previous work. Based on this theoretical framework, a necessary condition on
the pseudo-potential (plasma pressure) to allow for force-free 1D VM equilibria
is formulated. It is shown that linear force-free 1D VM solutions, which so far
are the only force-free 1D VM solutions known, correspond to the case where the
pseudo-potential is an attractive central potential. A general class of
distribution functions leading to central pseudo-potentials is discussed.Comment: Physics of Plasmas, accepte
Exploring the Expectations of Transport Professionals Concerning the Future Automobility System: Visions, challenges and transitions
A mixture of potentially significant changes in technology, commercial structures and social practices are currently entering the automobility system. These changes have the potential to combine together and lead to a substantial shift in the manner in which society fuels, owns and makes use of its cars. This paper reports a research project which made use of focus groups to examine the narratives of British transport professionals concerning forthcoming developments in the automobility system. Specific attention was given to what the expectations for future change in automobility are, if these changes will likely lead to a transition towards a more sustainable system and the manner in which a transition of this nature could be facilitated. The oral testimony offered during the focus groups has been assessed qualitatively using thematic analysis. The results suggest that there is a commonly held view that the automobility system is entering a stage of flux which may lead to considerable changes in system configuration. However, the attainment of a sustainable transition for the system will likely be inhibited by a series of institutional, societal and physical barriers which may restrict system developments
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