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Laboratory chamber experiments simulating in-situ plasma vitrification for geoenvironmental concernsMayer, Kate A. 12 1900 (has links)
No description available.
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Transformation of processed kaolin by plasma magmavicationCeles, Josepha D. 08 1900 (has links)
No description available.
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The Structural and Geomorphic Development of Active Collisional Orogens, from Single Earthquake to Million Year Timescales, Timor Leste and New ZealandDuffy, Brendan Gilbert January 2012 (has links)
The structure and geomorphology of active orogens evolves on time scales ranging from a single earthquake to millions of years of tectonic deformation. Analysis of crustal deformation using new and established remote sensing techniques, and integration of these data with field mapping, geochronology and the sedimentary record, create new opportunities to understand orogenic evolution over these timescales. Timor Leste (East Timor) lies on the northern collisional boundary between continental crust from the Australian Plate and the Banda volcanic arc. GPS studies have indicated that the island of Timor is actively shortening. Field mapping and fault kinematic analysis of an emergent Pliocene marine sequence identifies gentle folding, overprinted by a predominance of NW-SE oriented dextral-normal faults and NE-SW oriented sinistral-normal faults that collectively bound large (5-20km2) bedrock massifs throughout the island. These fault systems intersect at non-Andersonian conjugate angles of approximately 120° and accommodate an estimated 20 km of orogen-parallel extension. Folding of Pliocene rocks in Timor may represent an early episode of contraction but the overall pattern of deformation is one of lateral crustal extrusion sub-parallel to the Banda Arc. Stratigraphic relationships suggest that extrusion began prior to 5.5 Ma, during and after initial uplift of the orogen. Sedimentological, geochemical and Nd isotope data indicate that the island of Timor was emergent and shedding terrigenous sediment into carbonate basins prior to 4.5 Ma. Synorogenic tectonic and sedimentary phases initiated almost synchronously across much of Timor Leste and <2 Myr before similar events in West Timor. An increase in plate coupling along this obliquely converging boundary, due to subduction of an outlying continental plateau at the Banda Trench, is proposed as a mechanism for uplift that accounts for orogen-parallel extension and early uplift of Timor Leste. Rapid bathymetric changes around Timor are likely to have played an important role in evolution of the Indonesian Seaway.
The 2010 Mw 7.1 Darfield (Canterbury) earthquake in New Zealand was complex, involving multiple faults with strike-slip, reverse and normal displacements. Multi-temporal cadastral surveying and airborne light detection and ranging (LiDAR) surveys allowed surface deformation at the junction of three faults to be analyzed in this study in unprecedented detail. A nested, localized restraining stepover with contractional bulging was identified in an area with the overall fault structure of a releasing bend, highlighting the surface complexities that may develop in fault interaction zones during a single earthquake sequence. The earthquake also caused river avulsion and flooding in this area. Geomorphic investigations of these rivers prior to the earthquake identify plausible precursory patterns, including channel migration and narrowing. Comparison of the pre and post-earthquake geomorphology of the fault rupture also suggests that a subtle scarp or groove was present along much of the trace prior to the Darfield earthquake. Hydrogeology and well logs support a hypothesis of extended slip history and suggests that that the Selwyn River fan may be infilling a graben that has accumulated late Quaternary vertical slip of <30 m. Investigating fault behavior, geomorphic and sedimentary responses over a multitude of time-scales and at different study sites provides insights into fault interactions and orogenesis during single earthquakes and over millions of years of plate boundary deformation.
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Continuous Deposition of Carbon Nanotubes in an Arc-reactor and their Application in Field Emission DevicesShastry, Rahul January 2007 (has links)
Carbon nanotubes have become one of the most important building blocks critical to nanotechnology. Carbon nanotubes have attracted the interests of many scientists since their discovery due to their remarkable properties and have been widely used for various applications. However, the bottle neck in nanotube research has been the lack of a cheap, continuous and fast nanotube production method. This study concerns a reactor where nanotubes are continuously deposited on a carbon substrate using arc discharge at atmospheric pressure. This process appears to be the first to employ an arc discharge as the method for continuous mass deposition of nanotubes on a substrate. This nanotube deposition method eliminates the generic multistep process of nanotube deposition on substrates for its use in many applications. The effect of various parameters influencing growth and morphology of nanotubes on the substrate in the arc reactor (inter-electrode gap, atmosphere composition, current density, flushing, substrate type and speed and catalyst) have been systematically explored to optimise nanotube growth. The field emission properties of the nanotube laden substrate are studied for use and applicability as electron emitters. The nanotube samples demonstrated superior emission properties, low turn-on field and excellent current stability when put into applications such as a luminescent tube and an ionisation sensor. Theoretical modelling of the behaviour of a single nanotube during field emission was performed using finite element analysis software (COMSOL 3.2) to understand the effect of nanotube length, diameter, and vacuum gap on an individual nanotube. The results reveal that resistive heating (temperature) limits the maximum current carried by an individual nanotube. Furthermore, a new growth model is introduced to explain the formation of nanotubes from graphene fragments and nanocrystallites, due to polarisation of carbon species near the electrode surface suggesting that carbon vapour is unlikely to be responsible for nanotube growth.
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Studies on arcing phenomena at high current dischargesSchneider, Wolfgang January 2000 (has links)
No description available.
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Novel Designs for Photovoltaic Arrays to Reduce Partial Shading Losses and to Ease Series Arc Fault DetectionShams El-Dein, Mohamed 06 November 2014 (has links)
A mismatch in a photovoltaic array implies differences in the I-V characteristics of the modules forming the array which can lead to significant energy losses known as mismatch losses. The sources of mismatch losses could be easy- or difficult-to-predict sources. This thesis proposes novel designs for photovoltaic arrays to reduce mismatch losses.
The mismatch from easy-to-predict sources and its resulting losses can be reduced by altering the interconnection of the array. Therefore, this thesis proposes an optimal total-cross-tied interconnection, based on a thorough mathematical formulation, which can significantly reduce mismatch losses from easy-to-predict sources. Application examples of the operation of the optimal total-cross-tied interconnection under partial shading are presented.
The effect of partial shading caused by easy- or difficult-to-predict sources can be considerably reduced by photovoltaic array reconfiguration. This thesis proposes a novel mathematical formulation for the optimal reconfiguration of photovoltaic arrays to minimize partial shading losses. The thesis formulates the reconfiguration problem as a mixed integer quadratic programming problem and finds the optimal solution using branch-and-bound algorithm. The proposed formulation can be used for equal or non-equal number of modules per row. Moreover, it can be used for fully reconfigurable or partially-reconfigurable arrays. Application examples of the operation of the reconfigurable photovoltaic array under partial shading are presented.
Finally, the recently updated American National Electric Code requires the presence of a series arc fault detector in any Photovoltaic installation operating at a voltage greater than or equal to 80V. However, the Photovoltaic market nowadays lacks the presence of an accurate series arc fault detector that can detect series arc faults and discriminate between them and partial shading. The work in this thesis proposes an algorithm that can detect series arc faults and discriminate between them and partial shading in total-cross-tied arrays. This algorithm is based on the measurement of instantaneous row voltages.
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Double-Sided Arc Welding of AZ31B Magnesium Alloy SheetShuck, Gerald January 2013 (has links)
Magnesium alloys are of interest to the automotive industry because of their high specific strength and potential to reduce vehicle weight and fuel consumption. In order to incorporate more magnesium components into automotive structures, efficient welding and joining techniques must be developed. Specifically, a method of making butt-joint welds must be found in order to use sheet magnesium alloys in the form of tailor-welded blanks for structural applications. The existing welding processes each have disadvantages when applied to magnesium alloy sheet.
The double-sided arc welding (DSAW) process has been shown to produce high quality welds in aluminum alloy sheet, for tailor-welded blank applications. The DSAW process has not yet been applied to AZ31B magnesium alloy, which has thermo-physical and oxide forming properties similar to those of aluminum alloys. Therefore, this research explores the weldability of AZ31B magnesium alloy, using the DSAW process.
Experimental, butt-joint configuration welds were made in 2 mm thick AZ31B-H42 magnesium alloy sheet. Acceptable welds have been produced using welding speeds ranging from 12 mm/s to 100 mm/s and welding powers from 1.6 kW to 8.7 kW. The influence of these parameters on the appearance, geometry, mechanical properties and microstructure of the resulting welds was investigated.
Optimal appearance, geometric profile and mechanical properties were obtained at the lowest welding speeds and powers. Under these conditions, mechanical properties of the weld metal were equivalent to those of the fully annealed (0-temper) base metal. However, progressive deterioration in appearance, geometry and mechanical properties occurred at higher welding speeds.
The deterioration in mechanical properties was associated with 2 microstructural defects that were observed at higher welding speeds: 1) the formation of larger amounts of Mg17Al12 -phase particles, at the grain boundaries, and 2) the formation of solidification shrinkage micro-porosity at these same inter-granular locations.
This research demonstrates that the DSAW process is capable of producing acceptable quality, butt-joint welds in AZ31B magnesium alloy sheet at welding speeds up to 100 mm/s. However, in order to achieve the highest quality welds, low welding power, and, low welding speed, should be used. The highest quality welds were produced at welding speeds of 12 mm/s.
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Recent volcanic and tectonic evolution of the Southern Mariana arcBecker, Nathan C January 2005 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 150-166). / Also available by subscription via World Wide Web / xv, 166 leaves, bound col. ill., col. maps (1 fold.) 29 cm
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The plot against character : Towards a character-centred model of screenwritingMullins, Anthony January 2004 (has links)
Summary of exegesis A review and critique of some of the most popular screenwriting concepts as well as a proposal for a screenplay model that seeks to conceptually synthesise character with structure. Summary of Screenplay When Andrew's infamous punk band is forced to earn extra money playing part-time as a children's act they unexpectedly discover a potentially lucrative market for their music. Unfortunately, playing to screaming three year olds is not the rock and roll lifestyle Andrew was hoping for as he approaches his thirtieth birthday. Tensions within the band grow and the old friends are forced to decide not only the future of their music, but also rest of their lives.
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Research Grant Funding and Peer Review in Australian Research CouncilsMow, Karen Estelle, n/a January 2009 (has links)
This thesis considers the effects of research funding process design in the
Australian Research Council (ARC) and the National Health and Medical
Research Council (NHMRC). The program delivery mechanisms that the
ARC and NHMRC use differ in detail and each council claims to be using
the best selection model possible. Neither council provides evidence that
peer review is the best possible way of delivering government funding for
research and neither can produce empirical evidence that they use the
best possible peer review model to determine excellence.
Data used in this thesis were gathered over several years, forming a
comparative case study of the Australian Research Council and the
National Health and Medical Research Council, with illustrative data from
comparable international organizations in the UK and USA. The data
collection included: a survey of applicants, semi-structured interviews
with experienced panel members and former staff, observation of selection
meetings, and examination of publications by and about the research
councils.
Researchers firmly believe in peer review and their confidence enables the
system to function. However, the mechanisms of grant selection are not
well understood and not well supported by applicants, who criticize the
processes used to assess their work, while supporting the concept of peer
selection.
The notion of excellence is problematic; judgements of excellence are made
within frameworks set by the research councils and vary across
disciplines. Allocation of research funding depends on peer review
assessment to determine quality, but there is no single peer review
mechanism, rather, there exist a variety of processes.
Process constraints are examined from the perspectives of panel members,
peer reviewers, council staff and applicants. Views from outside and inside
the black box of selection reveal the impacts of process design on
judgements of excellence and decision-making capacity. Peer reviewers in
selection panels are found to use a range of differentiating strategies to
separate applications, with variance evident across disciplines and
research councils. One dominant criterion emerges in both the ARC and
NHMRC processes, track record of the applicants.
Program delivery mechanisms enable and constrain selection but every
peer panel member has to make selection decisions by defining discipline
standards and negotiating understandings within the panel. The extent to
which peers can do this depends on the number of applications assigned
to them, the size of the applicant field, and the processes they have to
follow. Fine details of process design, panel rules and interactions are the
tools that shape funding outcomes.
Research councils believe they are selecting the best, most meritorious
proposed research. However, I show in this thesis that the dominant
discriminator between applicants in Australian selection processes is
track record of the applicant. This effect is the result of several factors
operating singly or in concert. Researcher track record, largely determined
by quality and number of journal publications, is considered to be the
responsibility of universities but support for this capacity building has not
been systematically provided in Australian universities.
Reliance on track record to determine the outcomes of all but the very best
applications is very like awarding prizes for past work and is significantly
different from the models of grant selection that operate in comparable
international research councils.
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