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Modelling of Supersonic Combustion using a Filtered Rankine-Hugoniot LES-FDF Method
No full textA new energy consistency scheme using the filtered Rankine-Hugoniot (R-H) relation is tested and validated for a hybrid Eulerian/Lagrangian Large Eddy Simulation Filtered Density Function (LES-FDF) numerical method for modelling compressible high-speed combustion. This involves computing enthalpy redundantly on an Eulerian finite volume scheme, and an ensemble of Lagrangian particles which uses the filtered R-H relation to account for sub-grid effects. The method is tested against a three-dimensional, practical flame case: a turbulent non-premixed shear layer into an oblique shock. This was done
including viscosity, and with a 35-step, 20-species chemistry model. Instantaneous and time-averaged measurements across the whole domain show numerically consistent temperature and enthalpy, validating energy consistency. Species were found to be better resolved in the FDF solver. Also, exclusion of Lagrangian sub-grid kinetic energy relaxation is shown to increase energy consistency error between solvers. Further, LES-FDF
results were validated against DNS data showing low physical error. Overall, these results successfully validate the application of this novel method in practical, three-dimensional flame cases
Type 2 Diabetes and Cognitive Impairment: Prevalence in an Outpatient Clinic and Opportunities for Improvement in Quality Use of Medicines
No full textThere is an association between diabetes and cognitive impairment which may impact diabetes self-care and outcomes both in the community and in hospital. Screening of older people with diabetes for cognitive impairment has been recommended to identify need for additional support and to minimise potential risks,
but this is not routine practice in Australia. The primary aim of this thesis is to contribute to addressing this gap by assessing cognitive function in older people living with type 2 diabetes attending an ambulatory care diabetes clinic at a tertiary referral hospital to identify the scope of the issue locally. The Montreal Cognitive Assessment and Problem Areas in Diabetes questionnaires (Appendices 1 and 2) were completed, n=50. The key finding was that 36/50 (72%) patients were identified with a MoCA score <26, with a mean score
in this group of 22.6 (SD 2.3).
The secondary aim was to identify potential adverse medication impact associated with cognitive impairment in diabetes. A retrospective review of 100 inpatients prescribed a sulphonylurea was conducted to identify episodes of hypoglycaemia. Documented cognitive impairment was more prevalent in the 34 patients identified to have experienced hypoglycaemia (RR 1.64, 95% CI 0.77-3.5).
This thesis identifies the local feasibility and potential significance of cognitive screening in people with type 2 diabetes. This informs future practice to embed cognitive screening to prioritise people who may benefit from focused review of medication. This may minimise risk of medication adverse effects, in the community as well as on admission to hospital, and potentially optimise management of both
diabetes and cognitive impairment
Enhancing Capabilities through Legal Empowerment: Freedom for Women from Intimate Partner Violence?
No full textLargely due to the international human rights law framework, legislation addressing intimate partner violence (referred to in this thesis as Standard IPV Legislation) has been introduced in more than 85% of countries across the globe.
This thesis argues that the implementation of Standard IPV Legislation should be supported by legal empowerment programming designed to help IPV survivors understand and use the law. It advocates for the design of programming by reference to key principles of capability theory in aid-dependent postcolonial contexts in which human rights concepts and discourse remain contested. This thesis argues that well-designed programming can enhance the perceived legitimacy of the law; ameliorate barriers to rights-based programming; and take seriously the perspectives, priorities and lived experiences of the IPV survivors at which it is aimed.
To examine how a capabilities-informed approach to legal empowerment programming might work in practice, and to evaluate the potential of such an approach, this thesis uses the case study of the Family Protection Act 2014 in Solomon Islands. It draws on original qualitative research that demonstrates both the benefits of the international human rights law framework for those seeking the reduction of IPV, and the common ideological and practical barriers that can arise in response to rights-based approaches to IPV reduction.
Ultimately this thesis employs the capability approach to capitalise on the benefits of the international human rights law discourse and framework while ameliorating barriers that come with it. It draws on insights from both the literature and the Solomon Islands case study to explore how the capability approach can be operationalised to enhance the accessibility and effectiveness of Standard IPV Legislation in aid-dependent postcolonial contexts. It provides a concrete example of a capabilities-informed tool that could be used to do so in practice
Grazing Behaviour and the Microbiome of Extensively Managed Australian Alpacas
No full textThe Australian alpaca industry has continued to develop to provide an alternative natural fibre to wool, angora and mohair since their introduction in the 1990’s. The production of alpacas in Australia provides an alternative natural fibre industry along a growing eco-tourism industry as well as meat production. This developing industry has an estimated farm gate value of $13.5 million. However, little is known about the demographic structure of the Australian alpaca industry, as well as baseline veterinary, behavioural, and welfare management extending to the rumen and faecal microbiome. The aims of this thesis were to:
1. Establish the current Australian alpaca industry demographics relating to herd size and production purpose, identifying common management practices and issues;
2. Create a baseline understanding of alpaca herd paddock behaviour in an extensive production system;
3. Trial on-farm monitoring technology, including cameras and real-time tracking tags, as a tool to research and manage animal behaviour and welfare; and
4. Characterise the faecal microbiome of alpacas raised in south-eastern Australia to create baseline microbiome data.
The work presented in thesis provides new data on the paddock behaviour of Australian alpacas in an extensive environment as well as highlighting practical examples of the use of livestock monitoring technology to improve alpaca monitoring and management with further opportunities for industry development and adoption. Additionally, a baseline characterisation of the faecal microbiome of Australian alpacas establishes a valuable reference point for future alpaca-focused research and veterinary applications. Further development of alternative fibre industries, including the Australian alpaca industry, provides diversification of products for use in textiles for a wide consumer base as well as an alternative livestock production option for varying environments
Introducing Money into the Framework of a General Equilibrium Model
No full textMoney is an important factor in economic activities but in a general equilibrium framework the concept of money seems to be absent. In fact money is often considered only as a ‘veil’ in hiding real economic activities, and therefore it has been ‘lifted’ out of the model so that the underlying ‘real’ activities in an economy can be examined more clearly. However, in practice, money is more than just a ‘veil’. It can provide a platform on which many activities and/or commodities can be conceived, produced and exchanged. Money is also a store of value, not of its own, but of others, and with its purchasing-power money can enable its holder to have access to, and command the usage of, many other commodities and labour (human-time) to achieve certain objectives. Money therefore can be considered as part of the infrastructure of an economy which helps the economy to grow and prosper. In the past, economic theories of money and theories of (labour and commodity) values have looked at these two sides of an economy as though they are governed by different ‘laws’, but in fact, there is only one set of laws which govern both the price of money as well as the values of commodities and labour. Since money can act as a means of exchange, it therefore can also act as a constraint on this exchange. This means conceptually and mathematically, the ‘value of money’ is actually just the Lagrangian shadow price of this monetary constraint, but expressed in terms of the values of commodities and labour (not in terms of the ‘value of money’ itself, otherwise this is circular reasoning). If a ‘real’ economy is considered as though consisting of many different value-chains linking all activities together from producers to consumers, then money can act as the shadow price level of all these activity-chains. In this paper, we examine the interactions between the different value-chains and their shadow prices, in a general equilibrium economic model. Since monetary exchange is actually at the core of almost every economic activity in a modern economy, a study of the nature and ‘values’ of these exchanges is important for a better understanding of the working of a ‘real’ economy, and the theory of general equilibrium is a useful foundation or platform on which to conduct this study
An improved method of capture and immobilisation for medium to large-size macropods
No full textMacropods are very susceptible to stress during capture. Capture methods for macropods
fall into two categories: trapping and darting. Trapping by nets or a triggered trap mechanism is
commonly used for small macropods. Darting is most often used for large macropods that are
more prone to stress and capture myopathy when caught in traps. Aim. To describe a modified
‘nylon drop-net’ technique for safely capturing medium to large macropods; and post-capture
treatments that reduce stress and the potential for myopathy. Methods. We used a drop-net to
capture 40 agile wallabies (Notamacropus agilis) (24 females and 16 males), ranging in weight
from 6 to 24 kg. For immobilisation, a single dose of intramuscular Diazepam (1 mg/kg) and
Richtasol, a multivitamin, was administered to reduce the risk of capture myopathy. The longer-term
effects of capture on animal condition were monitored in 34 radio-collared individuals for 2 months.
Key results. No deaths occurred during or as a result of capture or in the 8 weeks following capture.
Conclusions. Our modified drop-net and handling/treatment regime provides a cost-effective
method for capturing medium and small-sized macropod species with very low risk of mortality or
morbidity. Implications. Our methods improve the welfare and safety of captured medium-sized
macropods
Deep Learning Methods to Improve the Utility and Reliability of dMRI Data
No full textDiffusion MRI (dMRI) is a powerful neuroimaging technique that provides non-invasive insights into brain tissue microstructures by measuring water diffusion. However, due to various acquisition constraints and the inherent low signal-to-noise ratio, dMRI data often suffer from issues related to both utility and reliability. Specifically, clinical dMRI data acquired with limited angular resolution cannot be fully utilized, reducing its applicability (utility issue). Additionally, dMRI data containing insufficiently corrected artifacts can lead to unreliable measures, compromising the validity of subsequent analyses (reliability issue). These two challenges significantly hinder the productivity of dMRI studies and can result in biased clinical or research outcomes. Addressing both the utility and reliability of dMRI data is therefore critical to improving its overall effectiveness.
In this thesis, we propose two deep learning methods to tackle these issues. The first method, DirGeo-DTI, leverages diffusion gradient information to generate angular resolution-enhanced DTI from a minimal set of diffusion-weighted images, thereby significantly improving the utility of dMRI data. The second method, UdAD-AC, is an unsupervised deep learning framework designed to detect artifacts in dMRI data without requiring annotated training data, thus enhancing the reliability of the data.
Extensive experiments on public datasets demonstrate the effectiveness of both proposed methods, with each achieving superior performance in their respective tasks. Furthermore, evaluations highlight the clinical impact of these methods, demonstrating their feasibility for integration into clinical practice and their potential to significantly improve the quality of dMRI-based research and outcomes
Teaching and Learning English from a Global Englishes Perspective in an Indonesian University: Perception and Practice
No full textThis study explores teaching and learning English from the perspective of Global Englishes (GE) as
perceived by Indonesian tertiary EFL teachers, focusing on their views and practices within the
university context. Guided by Bronfenbrenner's Nested Ecological Framework (NEF), it examines the
interconnected systems shaping language learning, including how GE influences teaching
approaches and its integration into Task-Based Language Teaching (TBLT) through classroom
materials and practices.
The NEF as a theoretical construct and TBLT under Global Englishes Language Teaching (GELT)
perspective are used to develop a writing program in an Indonesian university. By combining the
NEF, TBLT, and GELT perspectives, the study aimed to develop a writing program that was not only
effective but also relevant and culturally appropriate for Indonesian university students. Underpinned
by this theoretical framework, a qualitative paradigm was adopted in an Indonesian university
involving teachers from the English Education Department. Research data was gathered from
various sources including surveys, classroom observations, teacher reflections, interviews, and
classroom materials.
The results of this study demonstrated that GELT offers a more inclusive and equitable approach to
English language teaching by valuing linguistic diversity and promoting effective communication.
While challenges such as developing a shared lingua franca and equitable assessment must be
addressed, the potential benefits of GELT for students and teachers are significant. By embracing
multilingualism and leveraging students' language skills, educators can create more engaging,
effective, and empowering learning environments. Multilingualism provides a solid foundation for
language learning, while GELT values linguistic diversity and promotes culturally sensitive instruction.
By incorporating these elements, educators can foster inclusive and effective language learning
experiences
Soil Moisture daily data for the Llara Landscape Rehydration Project
No full textLandscape rehydration is a method that aims to regenerate the agricultural landsacpe while remaining productive. This dataset consists of data from uncalibrated soil moisture probes installed at Llara in Narrabri on the landscape rehydration project. The data is collected from 32 soil moisture probes in two 40 ha experimental pasture fields down to 1m20 and 1m60 depth and summarised to daily values. The two fields called Weir West and Weir East consist of one half "control" and one half "treatment" where landscape rehydration practices have been implemented. The data covers 2022 - 2024, but will be updated over time
Exploring evolutionary rates and patterns of diversification across the Tree of Life
No full textMy thesis provides substantial insight into evolutionary processes across the Tree of Life. I have
analysed the geological record as well as phenotypic traits and genomes from extant organisms to
better understand the processes of diversification and change. I begin by challenging the notion that
the diversification of flowering plants was intimately linked to a contemporaneous diversification of
pollinating insects. This evolutionary event, which propelled flowering plants to dominate terrestrial
landscapes, may instead have been bolstered by unique environmental factors, and by insect
pollinators that were primed by previous interaction with seed plants. I then examine the tempo of
evolution for many diverse taxa by inferring evolutionary rates. I first validate and assess five
methods for detecting evolutionary rate correlations between molecular sequences and
morphological traits, using a comprehensive simulation study with thousands of replicate data sets.
After determining the most statistically accurate and powerful methods, I apply these methods to
diverse taxa from the eukaryote Tree of Life. This spans groups including, but not limited to, worms,
tetrapods, fish, insects, plants, and parasites. In doing so, I uncover powerful evidence for decoupled
evolutionary rates of molecules and morphology across all groups tested, demonstrating the
disparate mechanisms that govern the evolution of morphology, which is under the constraint of
natural selection, and molecules, which exhibit more stochastic evolution. Finally, I analyse
evolutionary rates in land plant genomes, testing the link between rates in the three genomic
compartments of land plants (nucleus, chloroplast, and mitochondrion). In this chapter I demonstrate
that there is a shared evolutionary rate between the genomic compartments in land plants –
effectively extending the hypothesis of 'mitonuclear covariation' from animals to plants