8,432 research outputs found
Fully submerged composite cryogenic testing
New methods for marine salvage and decommissioning of structures in the open sea are continually being sought in order to improve control and lower operational costs [1]. The concept design of a lightweight, cryogenic, marine, heavy lift, buoyancy system has been investigated [2]. The objective is to be able to raise or lower high mass objects controlled solely from a surface support vessel. The overall design concept and associated system development issues have been discussed previously. A number of the sub-systems in one complete buoyancy system involve considerable design and development, these include: structural design of the buoyancy chamber, mechanical systems to control and connection to the lift device, the cryogenic system itself and overall process control systems. The main area of concern in the design process is the composite cryogenic Dewar. This is required to operate not only at temperatures as low as -196oC but also to withstand pressure differences exceeding 35bar. As such the composite materials have to perform in a very aggressive environment. This work details a method for fully submersed composite cryogenic testing in order to qualify the materials for use in the Dewar of the buoyancy system
The Effect of LHC Jet Data on MSTW PDFs
We consider the effect on LHC jet cross sections on partons distribution
functions (PDFs), in particular the MSTW2008 set of PDFs. We first compare the
published inclusive jet data to the predictions using MSTW2008, finding a very
good description. We also use the parton distribution reweighting procedure to
estimate the impact of these new data on the PDFs, finding that the combined
ATLAS 2.76 TeV and 7 TeV data, and CMS 7 TeV data have some significant impact.
We then also investigate the impact of ATLAS, CMS and D0 dijet data using the
same techniques. In this case we investigate the effect of using different
scale choices for the NLO cross section calculation. We find that the dijet
data is generally not completely compatible with the corresponding inclusive
jet data, often tending to pull PDFs, particularly the gluon distribution, away
from the default values. However, the effect depends on the dijet data set used
as well as the scale choice. We also note that conclusions may be affected by
limiting the pull on the data luminosity chosen by the best fit, which is
sometimes a number of standard deviations. Finally we include the inclusive jet
data in a new PDF fit explicitly. This enables us to check the consistency of
the exact result with that obtained from the reweighting procedure. There is
generally good, but not full quantitative agreement. Hence, the conclusion
remains that MSTW2008 PDFs already fit the published jet data well, but the
central values and uncertainties are altered and improved respectively by
significant, but not dramatic extent by inclusion of these data.Comment: 63 pages, 50 figures. Final version. Some added discussion and
improved figure
Use and abuse of statistics in tobacco industry-funded research on standardised packaging
In this commentary we consider the validity of tobacco industry-funded research on the effects of standardised packaging in Australia. As the first country to introduce standardised packs, Australia is closely watched, and Philip Morris International has recently funded two studies into the impact of the measure on smoking prevalence. Both of these papers are flawed in conception as well as design but have nonetheless been widely publicised as cautionary tales against standardised pack legislation. Specifically, we focus on the low statistical significance of the analytical methods used and the assumption that standardised packaging should have an immediate large impact on smoking prevalence
Decision making processes in people with symptoms of acute myocardial infarction: qualitative study
Objective To identify, the themes that influence decision making processes used by patients with symptoms of acute myocardial infarction. Design Qualitative study using semistructured interviews. Setting Two district hospitals in North Yorkshire. Participants 22 patients admitted to hospital with confirmed second, third, or fourth acute myocardial infarction. Main outcome measure Patients' perceptions of their experience between the onset of symptoms and the decision to seek medical help. Results Six main themes that influence the decision making process were identified: appraisal of In symptoms, perceived risk, previous experience, psychological and emotional factors, use of the NHS, and context of the event. Conclusions Knowledge of symptoms may not be enough to promote prompt action in the event of an acute myocardial infarction. Cognitive and emotional processes, individual beliefs and values, and the influence of the context of the event should also be considered in individual interventions designed to reduce delay in the event of symptoms of acute myocardial infarction
Atom Formation Rates Behind Shock Waves in Hydrogen and the Effect of Added Oxygen, July 1965 - July 1966
Formation rate of atomic hydrogen behind shock waves in hydrogen-argon mixture
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Near infrared spectroscopy of W51 IRS-2
Near-infrared spectra at 2.95-3.5 μm and 3.99-10 μm have been obtained towards W51 IRS-2 and its surroundings, in order to investigate the spatial variations in intensity of the 3.28 μm unidentified feature and the 4.05 μm Brackett-α line. The Br-α and 3.28 μm features occupy a broadly similar spatial zone, which is characterised by an unresolved core responsible for most of the emission, and an extended and considerably weaker halo. Grain properties required to excite the 4.28 microns line, the nature of the 3.28 μm emission, and its relation to the source structure are discussed
Supporting security-oriented, inter-disciplinary research: crossing the social, clinical and geospatial domains
How many people have had a chronic disease for longer than 5-years in Scotland? How has this impacted upon their choices of employment? Are there any geographical clusters in Scotland where a high-incidence of patients with such long-term illness can be found? How does the life expectancy of such individuals compare with the national averages? Such questions are important to understand the health of nations and the best ways in which health care should be delivered and measured for their impact and success. In tackling such research questions, e-Infrastructures need to provide tailored, secure access to an extensible range of distributed resources including primary and secondary e-Health clinical data; social science data, and geospatial data sets amongst numerous others. In this paper we describe the security models underlying these e-Infrastructures and demonstrate their implementation in supporting secure, federated access to a variety of distributed and heterogeneous data sets exploiting the results of a variety of projects at the National e-Science Centre (NeSC) at the University of Glasgow
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