665 research outputs found
The Knowledge of the Grid: A Grid Ontology
This paper presents a knowledge architecture and set of ontologies that can be used as the foundation to facilitate the matching of abstract resource requests to services and resources, to determine the functional equivalence of Grid middle wares and deployments and to allow the description of ‘hybrid’ compound Grids composed of individual heterogeneous Grids. This is necessary as in all these cases what is required is mediation between different views or descriptions of Grids, which requires a formal reference vocabulary. We present a framework and ontologies for achieving this
Magnetic field dependence of hole levels in self-assembled InAs quantum dots
Recent magneto-transport experiments of holes in InGaAs quantum dots [D.
Reuter, P. Kailuweit, A.D. Wieck, U. Zeitler, O. Wibbelhoff, C. Meier, A.
Lorke, and J.C. Maan, Phys. Rev. Lett. 94, 026808 (2005)] are interpreted by
employing a multi-band kp Hamiltonian, which considers the interaction between
heavy hole and light hole subbands explicitely. No need of invoking an
incomplete energy shell filling is required within this model. The crucial role
we ascribe to the heavy hole-light hole interaction is further supported by
one-band local-spin-density functional calculations, which show that Coulomb
interactions do not induce any incomplete hole shell filling and therefore
cannot account for the experimental magnetic field dispersion.Comment: 5 pages with 3 figures and one table. The paper has been submitted to
Phys.Rev.
Jig-Less Assembly for Aerospace Manufacture
Due to the high level of investment required to compete successively in the global aerospace
and automotive markets, these industries are forced to form partnerships wherever possible
and thereby share their resources appropriately. This in turn has brought about the
requirement to provide a standardized flexible design and manufacturing capability in which
interchangability and compatibility may take place.
Current assembly practices and associated tooling can be traced back to the earliest days of
aircraft production and have become relatively expensive and inflexible in today’s
environment.
The final assembly stage has been recognized to be a key area which has the potential to
offer substantial returns as well as play a major role in any change management process
within the organisation.
Assembly tooling, jigs and fixtures, are required to support and maintain positional
accuracy of components during assembly. Traditional jigs and fixtures make up for the short
comings at the product design and manufacturing phases and add significantly to the final
product costs and reduce flexibility in the production process.
Jig-Less Assembly Concept (JAC) has been defined and researched with the aim to integrate
and optimize various tools and techniques with which to reduce or eliminate the assembly
tooling currently in use.
The outcome of the research presents a comprehensive critique of the processes involved in
and pertaining to the assembly of typical airframe assemblies.
The thesis forms a platform from which to move forward towards the embodiment of the
concept of jig-less assembly. Particular attention is drawn from the research to the need for
appropriate organisational and management strategies as well as technical innovation in the
adoption of a jig-less approach to airframe assembly.
Together with BAe Airbus and Military this collaborative research seeks to define the scope
of JAC by identifying and evaluating the issues and constraints, to enable the development
of supportive techniques in unison with best practice engineering within a robust and
sustainable manufacturing system.
This commercially focused R & D required liaison and working at all levels within a variety
of industrial sites using live case studies at Filton and Chester.MPhi
Review of the Metropolitan Water Plan: Final Report
This report was commissioned by the NSW Cabinet Office to review the Metropolitan Water Plan 2004 (DIPNR, 2004a), and was undertaken by the Institute for Sustainable Futures at the University of Technology, Sydney and ACIL Tasman with technical advice from SMEC Australia. In February 2006, our interim review report (ISF, 2006) showed how the supply-demand balance in 2015 could be met with rain-fed supply and a suite of demand management initiatives, and how Sydneys water needs could be secured against the risk of severe drought by having the capacity to deploy groundwater and desalination
Combining to innovate: A collaborative interprofessional learning approach to delivering Tobacco Use Prevention and Cessation (TUPAC) education for undergraduate oral health students
This paper provides a description of a pilot project in Tobacco Use Prevention and Cessation (TUPAC) in response to a national and international trend to include TUPAC curriculum components in the clinical education of undergraduate oral health students. In order to deliver quality brief intervention strategies for smokers a need to adequately prepare oral health students was identified during student clinical placements. An interprofessional (IP) project team was established with membership from the University of Adelaide’s School of Dentistry, QuitSA, Cancer Council SA, the South Australian Dental Service (SADS) Somerton Park and TAFESA’s Faculty of Dental Studies to streamline the efficient use of resources and most importantly draw on a diverse range of interprofessional health care expertise. On the website for The UK Centre for the Advancement of Interprofessional Education (CAIPE) (2002) it states that “Interprofessional education occurs when two or more professions learn from and about each other to improve collaboration and the quality of care”. Through interprofessional learning (IPL) in classroom and clinical settings, second year Bachelor and Advanced Diploma oral health students were provided with the opportunity to develop an understanding of the respective roles of each health professional responsible for delivering positive health initiatives in the area of TUPAC. With limited national oral health curricula in the area of TUPAC, the project team forged links with the University of Manitoba’s Dental Hygiene Program, and the convenor of the TUPAC in Dental and Dental Hygiene Undergraduate Education European Workshops for curriculum benchmarking against evidence based criteria. Most importantly as the IP concept of health care considers the patient at the centre of the health care team, assessment was designed to encourage a patient centred approach through the review and analysis of a clinical case study. A formal evaluation of this project is currently in progress, however results were not yet available at the time of publication
Measurable \u3csup\u3e14\u3c/sup\u3eC in Fossilized Organic Materials: Confirming the Young Earth Creation-Flood Model
Given the short 14C half-life of 5730 years, organic materials purportedly older than 250,000 years, corresponding to 43.6 half-lives, should contain absolutely no detectable 14C. (One gram of modern carbon contains about 6 x 1010 14C atoms, and 43.6 half-lives should reduce that number by a factor of 7.3 x 10-14.) An astonishing discovery made over the past twenty years is that, almost without exception, when tested by highly sensitive accelerator mass spectrometer (AMS) methods, organic samples from every portion of the Phanerozoic record show detectable amounts of 14C! 14C/C ratios from all but the youngest Phanerozoic samples appear to be clustered in the range 0.1-0.5 pmc (percent modern carbon), regardless of geological ‘age.’ A straightforward conclusion that can be drawn from these observations is that all but the very youngest Phanerozoic organic material was buried contemporaneously much less than 250,000 years ago. This is consistent with the Biblical account of a global Flood that destroyed most of the air-breathing life on the planet in a single brief cataclysm only a few thousand years ago
Helium Diffusion Rates Support Accelerated Nuclear Decay
Two decades ago, Robert Gentry and his colleagues at Oak Ridge National Laboratory reported surprisingly high amounts of nuclear-decay-generated helium in tiny radioactive zircons recovered from Precambrian crystalline rock, the Jemez Granodiorite on the west flank of the volcanic Valles Caldera near Los Alamos, New Mexico [9]. Up to 58% of the helium (that radioactivity would have generated during the alleged 1.5 billion year age of the granodiorite) was still in the zircons. Yet the zircons were so small that they should not have retained the helium for even a tiny fraction of that time. The high helium retention levels suggested to us and many other creationists that the helium simply had not had enough time to diffuse out of the zircons, and that recent accelerated nuclear decay had produced over a billion years worth of helium within only the last few thousand years, during Creation and/or the Flood. Such acceleration would reduce the radioisotopic time scale from megayears down to months.
However, until a few years ago nobody had done the experimental and theoretical studies necessary to confirm this conclusion quantitatively. There was only one (ambiguously reported) measurement of helium diffusion through zircon [18]. There were no measurements of helium diffusion through biotite, the black mica surrounding the zircons. In 2000 the RATE project [14] began experiments to measure the diffusion rates of helium in zircon and biotite specifically from the Jemez Granodiorite. The data, reported here, are consistent with data for a mica related to biotite [17], with recently reported data for zircon [19] and with a reasonable interpretation of the earlier zircon data [18]. We show that these data limit the age of these rocks to between 4,000 and 14,000 years. These results support our hypothesis of accelerated nuclear decay and represent strong scientific evidence for the young world of Scripture
Spin polarization and magneto-luminescence of confined electron-hole systems
A BCS-like variational wave-function, which is exact in the infinite field
limit, is used to study the interplay among Zeeman energies, lateral
confinement and particle correlations induced by the Coulomb interactions in
strongly pumped neutral quantum dots. Band mixing effects are partially
incorporated by means of field-dependent masses and g-factors. The spin
polarization and the magneto-luminescence are computed as functions of the
number of electron-hole pairs present in the dot and the applied magnetic
field.Comment: To appear in Phys. Rev.
Enhancement of luminescence by pulse laser annealing of ion-implanted europium in sapphire and silica
Sapphire (Al2O3) and silica samples have been implanted with 400 keV europium ions at fluences between 5×1014 and 1×1016 ions cm-2. As-implanted, samples show luminescence at 622 nm, and although the intensity may be increased by furnace anneals up to 1000°C, higher temperatures, to 1200°C, result in less emission, as the impurity ions form precipitate clusters. This problem can be avoided by the use of pulsed laser anneals which dissociate the clusters and quench in atomically dispersed ions. The luminescence intensity has been increased by factors of 95 and 85 for sapphire and silica, respectively, relative to the initial implanted signal. On comparing with furnace anneals at 1200°C, the pulsed laser annealing is more effective, by factors of up to 45 times. Data for pulsed excimer and CO2 lasers are compared. Both types of laser appear to remove the ion-implanted radiation damage, but in the case of silica, higher luminescence performance was obtained with the excimer anneals. There was no evidence for diffusion of the implanted europium, as assessed by Rutherford backscattering spectrometry. © 1995 American Institute of Physics.We thank Barry Farmery for his help with the RBS work, and both the University of Ege in Turkey and the Science and Engineering Research Council for their financial assistance. We appreciate the use of a Lumonics (Hull Op- erations) Ltd. TEA CO, laser.Peer Reviewe
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