22 resultados para Cure fraction

em Queensland University of Technology - ePrints Archive


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Introduction: 3.0 Tesla MRI offers the potential to quantify the volume fraction and structural texture of cancellous bone, along with quantification of marrow composition, in a single non-invasive examination. This study describes our preliminary investigations to identify parameters which describe cancellous bone structure including the relationships between texture and volume fraction.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The main contribution of this paper is decomposition/separation of the compositie induction motors load from measurement at a system bus. In power system transmission buses load is represented by static and dynamic loads. The induction motor is considered as the main dynamic loads and in the practice for major transmission buses there will be many and various induction motors contributing. Particularly at an industrial bus most of the load is dynamic types. Rather than traing to extract models of many machines this paper seeks to identify three groups of induction motors to represent the dynamic loads. Three groups of induction motors used to characterize the load. These are the small groups (4kw to 11kw), the medium groups (15kw to 180kw) and the large groups (above 630kw). At first these groups with different percentage contribution of each group is composite. After that from the composite models, each motor percentage contribution is decomposed by using the least square algorithms. In power system commercial and the residential buses static loads percentage is higher than the dynamic loads percentage. To apply this theory to other types of buses such as residential and commerical it is good practice to represent the total load as a combination of composite motor loads, constant impedence loads and constant power loads. To validate the theory, the 24hrs of Sydney West data is decomposed according to the three groups of motor models.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Recent studies have detected a dominant accumulation mode (~100 nm) in the Sea Spray Aerosol (SSA) number distribution. There is evidence to suggest that particles in this mode are composed primarily of organics. To investigate this hypothesis we conducted experiments on NaCl, artificial SSA and natural SSA particles with a Volatility-Hygroscopicity-Tandem-Differential-Mobility-Analyser (VH-TDMA). NaCl particles were atomiser generated and a bubble generator was constructed to produce artificial and natural SSA particles. Natural seawater samples for use in the bubble generator were collected from biologically active, terrestrially-affected coastal water in Moreton Bay, Australia. Differences in the VH-TDMA-measured volatility curves of artificial and natural SSA particles were used to investigate and quantify the organic fraction of natural SSA particles. Hygroscopic Growth Factor (HGF) data, also obtained by the VH-TDMA, were used to confirm the conclusions drawn from the volatility data. Both datasets indicated that the organic fraction of our natural SSA particles evaporated in the VH-TDMA over the temperature range 170–200°C. The organic volume fraction for 71–77 nm natural SSA particles was 8±6%. Organic volume fraction did not vary significantly with varying water residence time (40 secs to 24 hrs) in the bubble generator or SSA particle diameter in the range 38–173 nm. At room temperature we measured shape- and Kelvin-corrected HGF at 90% RH of 2.46±0.02 for NaCl, 2.35±0.02 for artifical SSA and 2.26±0.02 for natural SSA particles. Overall, these results suggest that the natural accumulation mode SSA particles produced in these experiments contained only a minor organic fraction, which had little effect on hygroscopic growth. Our measurement of 8±6% is an order of magnitude below two previous measurements of the organic fraction in SSA particles of comparable sizes. We stress that our results were obtained using coastal seawater and they can’t necessarily be applied on a regional or global ocean scale. Nevertheless, considering the order of magnitude discrepancy between this and previous studies, further research with independent measurement techniques and a variety of different seawaters is required to better quantify how much organic material is present in accumulation mode SSA.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Urban stormwater quality is multifaceted and the use of a limited number of factors to represent catchment characteristics may not be adequate to explain the complexity of water quality response to a rainfall event or site-to-site differences in stormwater quality modelling. This paper presents the outcomes of a research study which investigated the adequacy of using land use and impervious area fraction only, to represent catchment characteristics in urban stormwater quality modelling. The research outcomes confirmed the inadequacy of the use of these two parameters alone to represent urban catchment characteristics in stormwater quality prediction. Urban form also needs to be taken into consideration as it was found have an important impact on stormwater quality by influencing pollutant generation, build-up and wash-off. Urban form refers to characteristics related to an urban development such as road layout, spatial distribution of urban areas and urban design features.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This thesis is a problematisation of the development and implementation of professional standards as the mechanism to enhance professionalism and teacher quality in the teaching force within Australia and, more specifically, Queensland. Drawing on tools from Foucauldian archaeological analysis, the dominant discourses of professionalism from the academic literature, Australian federal and state policy documents and narratives from Queensland teachers are examined. These data sets are then cross referenced, analysing the intersections and divergences between the different texts. Findings suggest that through policy, political strategy and derisory statements from various authoritative voices, the managerial discourse of professionalism through professional standards documents has been unduly privileged as a means of regulating teachers, despite the fact that teachers themselves do not share this dominant notion of professionalism. The teachers in this study proffer ‘new classical-practical professionalism’ as a counter discourse, or discourse of resistance, to managerialism. However, an application of Foucault’s theorisations on power-knowledge reveals that their spoken discourses mean they are in fact yielding to the discourse of professional standards as docile bodies.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Although mobile phones are often used in public urban places to interact with one’s geographically dispersed social circle, they can also facilitate interactions with people in the same public urban space. The PlaceTagz study investigates how physical artefacts in public urban places can be utilised and combined with mobile phone technologies to facilitate interactions. Printed on stickers, PlaceTagz are QR codes linking to a digital message board enabling collocated users to interact with each other over time resulting in a place-based digital memory. This exploratory project set out to investigate if and how PlaceTagz are used by urban dwellers in a real world deployment. We present findings from analysing content received through PlaceTagz and interview data from application users. QR codes, which do not contain any contextual information, piqued the curiosity of users wondering about the embedded link’s destination and provoked comments in regards to people, place and technology.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

CI chondrites are used pervasively in the meteorite literature as a cosmochemical reference point for bulk compositions[1], isotope analyses[2] and, within certain models of meteorite evolution, as an important component of an alteration sequence within the carbonaceous chondrite subset[3]. More recently, the chemical variablity of CI chondrite matrices (which comprise >80% of the meteorite), has been cited in discussions about the "chondritic" nature of spectroscopic data from P/comet Halley missions[4] and of chemical data from related materials such as interplanetary dust particles[5]. Most CI chondrites have been studied as bulk samples(e.g. major and trace element abundances)and considerable effort has also been focussed on accessory phases such as magnetites, olivine, sulphates and carbonates [6-8]. A number of early studies showed that the primary constituents of CI matrices are layer silicates and the most definitive structural study on powdered samples identified two minerals: montmorillonite and serpentine[9]. In many cases, as with the study by Bass[9],the relative scarcity of most CI chondrites restricts such bulk analyses to the Orgueil meteorite. The electron microprobe/SEM has been used on petrographic sections to more precisely define the "bulk" composition of at least four CI matrices[3], and as recently summarised by McSween[3], these data define a compositional trend quite different to that obtained for CM chondrite matrices. These "defocussed-beam" microprobe analyses average major element compositions over matrix regions ~lOOµm in diameter and provide only an approximation to silicate mineral composition(s) because their grain sizes are much less than the diameter of the beam. In order to (a) more precisely define the major element compositions of individual mineral grains within CI matrices, and (b)complement previous TEM studies [11,12], we have undertaken an analytical electron microscopy (AEM) study of Alais and Orgueil matrices.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Addresses often unanswered questions about the costs and benefits of resource-based development The first book to offer a suitably comprehensive critique of Western Australia's development path Provides a multi-facetted perspective thanks to its truly cross-disciplinary and cross-institutional authorship Globalisation and rapid social and environmental change in recent decades have brought into sharper focus not only the benefits but also the costs of economic development. The once assumed link between economic development and societal well-being is being increasingly questioned in the face of growing social and environmental problems and unfulfilled expectations concerning political and commercial decision-makers. The orthodox development dogma is being tested in particular in resource-based economies such as Western Australia, where globalisation pressures and the concomitant rise in the demand for natural resources highlight the difficulties of effectively balancing broader societal interests with those of industry and the state. This book provides a critical review of the socio-political, environmental and cultural state of play in Western Australia, offering an analysis of how resource-based developments are shaping the state and its people.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The use of the curse or cure dichotomy to frame a discussion around the impacts of mining is an oversimplification, not least in the emphasis on one or the other (as opposed to curse and cure). It is, however, a potent trope for engaging critically with the consequences of mining not only in narrow economic terms but also in regard to political, social and environmental costs and benefits. Further, as Goodman and Worth (2008: 201) point out, to engage with the resource curse or cure question is to also engage more broadly with “the internal contradictions of capitalist development” as evident, for example, in divisions “between those who benefit from and those who bear the costs of accumulation” and the many conflicts—political, social, economic, environmental—attending resource extraction. It is in this sense that this volume mobilises the ‘resource curse or cure?’ motif.