SACM - Australia
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Item Restricted Vortex-Induced Photo-Contact Electrification Synthesis of Func6onal Metal Nanomaterials(Flinders University, 2025-03-13) Alotaibi, Badriah; Raston, ColinMetal nanomaterials with precise control over their shape, morphology, and size (ranging from nanometers to micrometers), have gain significant interest due to the unique chemical, physical, thermal, op5cal, mechanical, and conduc5ve proper5es. These materials hold an immense poten5al for a wide range of applica5ons par5cularly in catalysis. Over the years, various synthesis methods have been developed including boAom-up and top-down. A notable progress has been occurred using these methods, for controlling the synthesis of zero-dimensional (0D), onedimensional (1D) and two-dimensional (2D) nanostructures. However, there are several limita5ons and challenges that s5ll to be address, including the necessity of using high amounts of reagents, long processing 5me, the use of chemical stabilisers, the high cost of the associated complex processing, and scalability issue. This dissertation focuses on creating a paradigm shift in metal nanomaterials synthesis to overcome its limitation, by using the Vortex Fluidic Device (VFD) which is a continuous flow reactor utilizing rotating liquid tubes to generate a dynamic thin film. This can enhance chemical reactions through increased mass transfer, micro-mixing, and shear stress applied to the dynamic thin film of liquid. Thin film microfluidics offer numerous benefits in chemical processing due to their large surface-to-volume ratios, resulting in reduced reaction times, precise control over residence time and temperature, enhanced safety measures, and crucially enable scalability considerations from the initial stages of research. This contribute significantly to the development of environmentally sustainable processes that are also economically feasible. My PhD research aimed at utilizing a cutting-edge VFD to establish an unprecedented method of generating pristine gold (Au), silver (Ag), and rhenium(Re) nanoparticles and gold@graphene oxide (Au@GO) nanocomposite, where the size and morphology of nanoparticles can be controlled in water and in the absence of added reducing agents or other excipients such as surfactants. This involves UV irradiation of an aqueous metal source in a thin film of liquid generated in the VFD within a rapidly rotating quartz tube, resulted in a charge transfer between dielectric surfaces during contact and separation known as Contact Electrification (CE). The CE phenomena occur at the solid (tube surface)-liquid interface, forming reactive oxygen species present, competing with CE reduction of metal on the surface of the tube coupled with the photo-induced oxidation of water. The findings establish a paradigm for VFD processing in water under such UV irradiation involving photo-induced CE, which allows access to different nanoparticles crystallization of 1D, 2D, 3D structures and composite materials beyond what is possible using traditional batch processing strategies, with the surfaces pristine and the overall processing having beneficial green chemistry metrics. These metal nanomaterials show promising potential for catalysis applications along with other possible uses currently under investigation. The VFD offers the advantage of synthesising nanomaterials by employing simple one-step methods that eliminate the use of chemical stabilizers and surfactants, while maintaining scalability.8 0Item Restricted The perspectives of clients and social welfare workers regarding support programs offered by non-profit organisations in Mecca, Saudi Arabia.(The University of Western Australia, 2024-09-12) Alzahrani, Ali Sarhan; Young, Susan; Eltaiba, NadaThis exploratory study aimed to explore the experiences of low-income individuals and social workers with low-income socioeconomic support programs in non-profit organisations in Mecca, Saudi Arabia. A multiple case study approach was used the collection of information from 33 clients and 17 social workers across five different organisations. While all clients participated in individual interviews, 9 social workers participated in individual interviews and 8 preferred to participate in 3focus groups. Social work was a guiding framework for understanding these experiences by considering their alignment with social work principles and theories of empowerment and systems. The results of the present thesis revealed that the organisational practices of non-profit organisations strongly influenced these experiences. Further, at the macro level, results revealed a randomness and overlap in the social care services provided by non-profit organisations. This was caused by a lack of cooperation and networking between non-profit organisations, which prompted duplication between organisations for both services and clients, as well as age gaps in coverage, especially for individuals aged 18–35. At the macro level, non-profit organisations indicated that they suffer from many challenges that limit the efficacy of their organisational practices, such as inefficiency in specialised human resources, a lack of policies and poor financial resources. They also indicated that important decisions related to their clients and services distribution did not align with the principles of social work—especially justice. At the micro level, clients were dissatisfied with policies that did not account for individual differences and with the low level of professionalism exhibited by social workers who expose clients to discrimination, neglect and abuse. Clients also expressed their fear of general social care policies that limit their benefit from programs such as starting small projects. Concurrently, social workers revealed the challenges they faced due to administrative challenges in their organisations, such as their smaller numbers compared to clients, lack of support and tools, discrimination in wages and insufficient professional development, which made them feel exhausted. The present thesis concludes that reforms must be implemented at all levels to realign the strategies of non-profit organisations with general social welfare policies, as well as to achieve the desired goals of Saudi Vision 2030. The study also contributed to identifying the importance of developing social work in Saudi society in a manner that is appropriate to it by emphasising the importance of increasing organisational performance by applying appropriate organisational practices. These practices should follow the social work framework and focus on justice, empowerment, and equity. This thesis also stresses the importance of respecting the dignity of low-income individuals and prioritising the development of social workers, identifying their capabilities and creating an appropriate work environment that enables them to practice effective professional practices.21 0Item Restricted SNAPLOGIC INTEGRATION AT REECE(RMIT University, 2025) Alotaibi, Abdullah Abdulaziz A; Bindu, Amal Chandrasenan; Trigunarsyah, BambangThis report examines the transformative integration of a century-old leader in the plumbing and bathroom supplies industry in Australia. Faced with the limitations of a legacy ERP system, which resulted in data silos and operational inefficiencies, Reece made a strategic decision to modernize its operations through intelligent integration. By partnering with SnapLogic, a pioneer in AI-driven integration platforms, Reece aimed to enhance its operational efficiency and foster seamless collaboration across its various systems. The report outlines the project's background, detailing how Reece transitioned from a monolithic ERP system to a best-of-breed software approach. This shift was motivated by the need for flexibility, improved customer service, and the ability to respond swiftly to market changes. After a thorough evaluation process, Reece selected SnapLogic for its user-friendly interface, robust capabilities, and alignment with Reece's vision for a scalable and future-proof solution. The implementation was executed using a phased approach, focusing on integrating critical systems such as Workday, Oracle, and Salesforce within an ambitious six-month timeline. Key findings of the report highlight the success of the SnapLogic integration in significantly improving Reece's operational efficiency, enhancing data visibility, and enabling data-driven decision-making. By breaking down data barriers and automating processes, the integration facilitated real-time insights, which enhanced both decision- making and customer service capabilities. Several lessons learned from the Reece- SnapLogic project are identified as critical for other organizations considering similar transformations. These include the importance of stakeholder engagement throughout the decision-making process, the necessity of comprehensive training programs for empowering employees, the effectiveness of a phased implementation strategy to minimize risks, and the value of leveraging data analytics to drive operational effectivenesS24 0Item Restricted Improving Energy Efficiency and Network Lifetime in IoT Systems: A Novel Theoretical Framework and Experimental Validation(La Trobe University, 2024-12-03) Almudayni, Ziyad; Soh, BenThe Internet of Things (IoT) integrates devices, sensors and actuators into a unified network that delivers a range of services to end-users through internet connectivity. Over the past decade, the demand for IoT devices has surged due to their ability to simplify and enhance everyday activities. However, maintaining network stability and optimising performance in IoT systems involves addressing several key factors, such as power consumption, cost, bandwidth, data rate and processing time. Despite significant advancements in IoT research, there is still a notable gap in comprehensive studies on reducing energy consumption across the diverse layers and components of IoT systems. This research addresses the need for an integrated framework to enhance power efficiency in IoT environments by focusing on five critical areas: IoT architecture, communication technologies, IoT application types, IoT application protocols, and overall challenges faced by IoT networks. The thesis presents three innovative approaches designed to improve the energy efficiency and network lifetime of IoT systems. The first approach introduces the constrained application protocol 45 (CoAP45), an enhanced protocol that minimises CPU usage by optimising server update mechanisms and thus reducing energy consumption for resource-constrained IoT nodes. The second approach, the mist fuzzy healthcare system (MFHS), leverages mist computing and fuzzy logic to reduce processing time and energy consumption by pre-allocating resources based on real-time data categorisation, significantly improving healthcare IoT applications. The third approach, the IoT-mist bat algorithm (IMBA), uses bio-inspired optimisation techniques to dynamically allocate resources in complex IoT environments, enhancing load distribution, task completion rate and energy efficiency. Extensive experimental evaluations demonstrate that these three approaches successfully extend the operational lifetime of IoT networks while reducing power consumption and processing delays. The results indicate that CoAP45, MFHS and IMBA provide viable solutions for addressing the limitations of existing protocols and frameworks, thereby contributing to more sustainable and effective IoT systems. This research offers a novel theoretical and practical framework for future studies aiming to optimise energy efficiency in IoT networks, with potential applications in healthcare, industrial automation, and smart city environments.56 0Item Restricted Corporate Greenwashing, Environmental Disclosure Regulation, and Cost of Bank Loans: International Evidence(University of Newcastle, 2024) Al Sharmah, Saleh; Shamsuddin, Abul; Duong,Huu; Li, JialongA primary objective of mandatory corporate environmental disclosure rules is to provide investors with material information on firms’ environmental performance and ensure corporate accountability for any environmental wrongdoings. However, corporate greenwashing, in which firms disseminate relatively benign environmental impacts while concealing more environmentally damaging ones, can severely compromise this objective. To investigate this issue, the first empirical study examines how the staggered introduction of corporate environmental disclosure mandates affects corporate greenwashing engagement worldwide . The primary finding shows that affected firms by these mandates significantly reduced their greenwashing by genuinely improving their overall environmental practices. This reduction is more pronounced among larger firms, those with greater analysts’ coverage, those less financially constrained, and affected firms in countries with greater environmental awareness norms. Further analysis reveals that through the green commitment channel, affected firms boosted green investments, implemented environmental reduction initiatives and adjusted operations, leading to a greenwashing reduction. Subsequently, affected firms experienced reduced financial performance. These findings highlight the effectiveness of environmental disclosure mandates in promoting substantive and transparent corporate environmental practices and disclosures and their negative consequences on corporate financial performance. The second empirical study argues that greenwashing borrowers, who selectively disseminate only favourable environmental information while withholding information on the most environmentally damaging actions, expose banks to higher informational and credit risks. Therefore, banks will likely charge greenwashing borrowers higher loan rates on their lent loans to compensate for enduring these two risks. To test this argument, this study uses data from 38 countries between 2005 and 2019 to examine the impact of firm-level greenwashing on bank loan costs. The findings show that banks charged higher rates to corporate greenwashers, but this effect is found only after the enforcement of the Paris Agreement in 2016. Further, this effect is more pronounced in countries with higher climate vulnerability, fewer Environmental Non-Governmental Organizations (ENGOs), and among borrowing firms with fewer analysts following them. Overall, the results highlight the negative impacts of corporate greenwashing engagement on corporate borrowing costs.14 0Item Restricted Discrete Choice Experiments: Constructions and Properties(RMIT University, 2025-01-06) Alamri, Abdulrahman Sultan S; Georgiou, SteliosThis thesis explores the construction, optimisation, and evaluation of discrete choice experiments (DCEs), a powerful method for understanding individual decision-making across various fields such as healthcare, marketing, transportation, and policy-making. By closely replicating real-world scenarios, DCEs provide critical insights into preferences, allowing researchers, manufacturers, and policymakers to make informed decisions about the features of products and services based on perceived utility. The purpose of this study is to enhance the efficiency and practicality of DCEs by addressing the gaps in their design and proposing novel methodologies that reduce complexity while maintaining robust statistical properties. The research is guided by four key questions: (1) evaluate current approaches for constructing efficient DCEs, (2) improve existing designs to enhance efficiency, (3) propose novel construction methods, and (4) compare the performance of new and existing designs under various criteria. The first research question examines optimal (orthogonal) methods for constructing DCEs. These approaches are assessed for their ability to minimise the number of choice sets while preserving essential design properties such as orthogonality and level balance. A detailed review, as published in Heliyon (Alamri, Georgiou, & Stylianou, 2023), highlights the relative strengths and limitations of these methods, offering a practical reference for researchers. This work provides insights into sample sizes needed for reliable experimentation and identifies techniques that achieve high efficiency under specific experimental conditions. The second research question focuses on improving D-optimal paired choice designs, particularly for main effects models. This work, published in Humanities and Social Sciences Communications (Alamri, Georgiou, & Stylianou, 2023), introduces a novel approach to address cases where the number of attributes equals the number of runs, as well as scenarios that involve attributes with varying levels. The proposed designs achieve up to a 37.5% reduction in the number of choice pairs at the cost of a maximum 10% loss in D-efficiency relative to an optimal design. These methodologies are further extended to accommodate higher-level attributes (l > 2), showcasing their versatility and practical applicability. Simulation studies confirm the robustness of the proposed designs, emphasising their potential to improve experimental precision while reducing respondent burden. By significantly reducing the complexity of experiments without compromising efficiency, these contributions provide practitioners with robust and scalable solutions. The third research question explores the development of novel three-level choice designs using the Box-Behnken approach. This methodology is applied to estimate both main effects and partial second-order interactions under the utility-neutral multinomial logit model. The introduction of this design offers a significant reduction in the size of the choice sets required, preserving the precision of the experimental results. These designs address a critical gap in the literature by providing compact yet highly efficient frameworks for multi-level attribute studies. Simulation studies confirm the robustness of the proposed designs, emphasising their potential to improve experimental precision while reducing respondent burden. This thesis advances the field of discrete choice experiments by proposing innovative methods that address long-standing challenges in design efficiency, scalability, and practicality. The contributions offer a systematic framework for researchers to construct efficient and accessible experiments across a wide range of applications. By integrating theoretical insights with practical solutions, this work establishes a robust foundation for future research, enabling the continued evolution of DCE methodologies to meet the demands of modern experimental research.22 0Item Restricted AI Conversational Agents in Healthcare for Type-2 Diabetes(University of Technology Sydney, 2024-09-12) Sawad, Abdullah Bin; Kocaballi, Baki; Prasad, Mukesh; Narayan, Bhuva; Lin, ShanshanType 2 diabetes (T2D) is a global health crisis with significant impacts on individuals and healthcare systems. This thesis develops AI conversational agents (CAs) to promote physical activity and lifestyle changes for those at risk of T2D through a multi-phase study, including a systematic review, a design framework, and empirical testing. The systematic review identified gaps in digital interventions, particularly the limited use of CAs in T2D prevention. A standardised framework was then developed, focusing on personalisation, user engagement, and proactive health management. This framework guided the iterative design and refinement of a CA prototype, tested across diverse populations in Sydney and Jeddah. The thesis integrated real-time activity tracking via Fitbit and enhanced conversational capabilities using large language models. Findings demonstrated that AI-driven, personalised interactions significantly encouraged physical activity, a key factor in preventing T2D progression. This thesis contributes to health informatics by demonstrating AI’s role in preventive healthcare. It highlights the importance of a user-centred design approach, ensuring that digital health tools are effective and align with the users’ needs and preferences. Future research should focus on long-term engagement strategies and integrating conversational agents with broader healthcare systems to enhance their effectiveness and reach.13 0Item Restricted EXAMINING THE PSYCHOSOCIAL AFFORDANCES OF ONLINE LEARNING: PERCEPTIONS OF GIFTED ADOLESCENTS AND THEIR TEACHERS(University of Wollongong, 2024) Alqahtani, Yasmin Saif s; Vialle, WilmaThis thesis investigated the psychosocial affordances of online learning as perceived by gifted adolescents, teachers, and counsellors across six gifted high schools in Saudi Arabia. Research on educational technology for gifted students is limited, especially in fostering psychosocial development through online learning. Gifted adolescents, diverse in social competence and psychosocial needs, often struggle with poor self-concept and social adjustment during adolescence. Drawing on Erikson’s (1963) Theory of Psychosocial Development and Gibson’s (1966, 1977, 1979) Affordance Theory as a framework, this study attempted to fill this gap by examining how online learning environments address the psychosocial needs of gifted students and evaluated their impact on psychosocial development. The study employed dataset triangulation, using quantitative analysis of strength-based survey results and qualitative assessment of participant attitudes, opinions, and behaviours, organising survey and interview data into thematic clusters. Data collected from 300 gifted students, ten gifted teachers, and six school counsellors revealed that online learning enhanced creativity and academic quality for gifted students. Technology was viewed as essential for self-directed learning and career readiness. However, opinions varied regarding its efficacy in addressing psychological needs and building community. Teachers prioritised learner-centred approaches and recognised their evolving role as facilitators in online environments yet exhibited varying levels of digital expertise. Educators expressed a favourable attitude towards digital tools for academic purposes, highlighting their potential to optimise the learning experience and address students’ psychological well-being. Qualitative data highlighted educators’ multifaceted role in fostering effective communication, creating positive learning environments, and supporting academic skill development. Overall, this study informs stakeholders about the value of psychosocial affordances in online learning environments.24 0Item Restricted Pulp response of hypomineralised first permanent molars: an in vitro study(The University of Western Australia, 2024-11-10) Almelhi, Nabil A; Anthonappa, Robert PBackground: Dentine hypersensitivity is common among children with MIH. The weaker and porous enamel in hypomineralised first permanent molars results in post-eruptive breakdown that can lead to pain and infection at a rapid rate. This can have a negative effect on children’s quality of life. The understanding behind dentine hypersensitivity remains unclear. More research is required detailing the pulp response of hypomineralised first permanent molars. Aims: This in vitro study sought to i. explore a new standardised protocol for histological study on sound teeth and its feasibility on hypomineralised first permanent molars. ii. investigate the pulp response of hypomineralised first permanent molars with respect to defect severity. Methodology: Mild and severe hypomineralised first permanent molars (n=17) were fixated in 4% formaldehyde solution, demineralisation used 17% EDTA for 8 weeks and processed for histological study following a standardised approach. Samples were cut at 4 μm thickness and stained with H&E. Microscopic imaging was obtained for each slide. Three different areas of interest were identified for qualitative analysis. Two classification systems were used to identify the pulp response. The first classification system identified inflamed from healthy pulp. The following classification categorised the pulp response as reversible or irreversible. Results: H&E staining revealed evidence of reactive tertiary dentine deposition, degenerative odontoblast cells, accumulation of inflammatory cells, and an increase in nerve fibres within the dentine-pulp complex of mild and severe hypomineralised first permanent molars indicating an inflammatory pulp response. Conclusions: An inflammatory response was evident in the dentine-pulp complex of mild and severe hypomineralised molars. The hard and soft tissue changes may help further explain the hypersensitivity seen in some children with MIH.4 0Item Restricted A Review Of The State Of The Arts And Progress In Separating Minerals Using Air Dense Medium Fluidisation With Two Other Enhancement Techniques; Vibration And Magnetic Field(The University of Newcastle, 2022) Alhussin, Mohammed; Moreno-Atanasio, Roberto; Kennedy, EricIn general, the valuable minerals are recovered mostly by wet separations in industrial practices, including froth flotation, cyclone, wet jigging for fine particulate ore. However, these techniques require large amounts of water. In addition, they are unsuitable for some minerals, such as some types of coals in cold regions that tend to form slime in a wet separation process. Therefore, several scientists and engineers have been investigating and developing dry separation techniques to replace the commonly used wet separations (Tang, 2017). In this research, the published literature has been reviewed to understand the state of the art of gas fluidisation in mineral separation using air dense medium fluidisation (ADMFB), vibrated dense medium fluidised beds (VDMFB) and magnetically stabilised fluidised beds (MSFB). It was found that ADMFB separators are most suitable for large particles, VDMFBs separators are best for medium size rang, and MSFB separators can handle fine coal particles. In addition, the lowest separation limit of fine coal particles using those mentioned above was one millimetre.31 0