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Efficient Poling Free Second Harmonic Generation in Silicon Nitride Loaded Lithium Niobate on Insulator
No full textThis thesis investigates efficient second harmonic generation in a thin film lithium niobate on insulator (LNOI) integrated photonic platform without the need to etch or domain engineer the lithium niobate. This approach has the potential to greatly simplify fabrication and make second order nonlinear devices routine building blocks for scalable lithium niobate photonic integrated circuits.The efficient second harmonic generation in LNOI waveguides is achieved by developing a comprehensive modelling framework, starting from fundamental one-dimensional slab simulations and progressing to rigorous two-dimensional waveguide simulations. Using this bottom-up design strategy, waveguides with normalized second harmonic generation efficiencies of up to 174% W⁻¹ cm⁻² are theoretically predicted. To further increase the conversion efficiency, the waveguide geometry is carefully engineered for tighter modal confinement and suppression of lateral leakage of the second harmonic light through a bound state in the continuum. This waveguide geometry enabled a predicted second harmonic generation efficiencies of up to 415% W⁻¹ cm⁻² and an experimentally measured normalized second efficiency of 300% W⁻¹ cm⁻². To further boost performance and fabrication tolerance, simulations are performed with a thin silicon dioxide layer introduced between the lithium niobate and silicon nitride thin-film. Simulations show enhancement of the optical confinement, and predict normalized conversion efficiencies as high as 1080% W⁻¹ cm⁻². To reduce the sensitivity of the bound state of the continuum to fabrication tolerances in the waveguide width, a dimple was introduced at the centre of the waveguide. This dimple was shown to improve robustness to fabrication variations. By combining the silicon dioxide layer and dimple design strategies it should be possible to achieve normalized efficiencies of up to 520% W⁻¹ cm⁻² that are less sensitive to fabrication tolerances, offering a waveguide component that could be made longer achieving an overall more efficient second harmonic device. These results establish bound state in the continuum assisted, geometry-engineered waveguides as a promising route for efficient second harmonic generation in photonic integrated circuits, eliminating the need for poling and etching of lithium niobate.</p
Exploring extended immersive simulation-based education to prepare undergraduate nursing students for professional practice: A scoping review
No full textBackground: Extended immersive simulation (EIS), a subset of simulation-based education (SBE), provides prolonged simulation experiences that replicate real-world professional practice. While extensive research exists on SBE, no scoping reviews have mapped EIS-based education’s impact on undergraduate nursing education. Aim: To investigate the literature on EIS related to undergraduates’ learning experiences and engagement. It evaluates teaching modalities and learner-centred approaches in EIS, exploring their impact on student engagement and learning outcomes. Method: Following the Joanna Briggs Institute framework, this review analysed 684 publications from PubMed and ProQuest (2012-2024). Two authors independently screened titles, abstracts, and full texts, using detailed analysis and thematic categorisation. Results: Fifteen papers met the criteria. Thematic analysis revealed three themes: Student-Centred Learning Approaches, Structure of EIS, and Simulation Outcomes in nursing programs. Conclusion: EIS and student-centred approaches improve nursing students’ learning and readiness. Despite limited literature, EIS boosts engagement and prepares students in a controlled environment. More research is needed on student support, facilitator training, and academic guidance. Combining EIS with traditional methods is recommended for optimal development</p
A Numerical Study of Particle Collision Dynamics and Charge Transfer in Microchannel Suspension Flows
No full textThe increasing integration of intermittent renewable energy sources into the market necessitates scalable and fast-responsive energy storage solutions. Traditional low-carbon mechanical and electrical methods like pumped hydro power and Lithium-Ion batteries have limitations in terms of response time, cost, lifespan, parasitic losses and storage capacity. This has led to renewed research into emerging technologies such as slurry electrode Electrochemical Flow Capacitors (EFC) and the Proton Flow Reactor (PFR), whereby electrical charge and hydrogen respectively are captured within flowing conductive particles via particle-particle (p-p) and particle-wall (p-w) collisions. Both systems rely on the pressure driven flow of dense colloidal suspensions confined within a channel geometry, where particle properties, volume fraction, channel geometry, and the mechanism of particle charge transfer play crucial roles in optimising performance. Understanding p-p and p-w interactions is therefore essential for improving these systems.Particle collisions in these flows play a critical role with respect to both bulk rheology and localised jamming events, and provide a critical link between frictional mechanics and hydrodynamics that manifest as intermittent phenomena such as discontinuous shear thickening. As such, we cannot describe these flows using a simple bulk suspension rheology. Particle collisions are also fundamental to the processes of charge transfer, and therefore must be discretely considered. In this study we investigate particle collisions in pressure-driven Stokes flow of dense non-Brownian frictional colloidal suspensions within a square micro-channel.To identify the most suitable method for modelling confined pressure-driven suspension flows such as the EFC and PFR, we reviewed and surveyed several numerical methods. These systems were categorised based on how they consider both the suspension medium and particulate domains. Generally, the suspension medium can be resolved via either a continuum-based method, such as the finite volume method, or by particle-based methods, where fictitious fluid particles are simulated and their interactions resolved to produce fluid characteristics. Methods that did not explicitly capture particle motion were not considered, as they are unable to resolve the necessary p-p interactions giving rise to hydrodynamic and charge transfer phenomena. Ultimately, the CFD-DEM approach, including lubrication interactions captured within the DEM code, was selected for its ability to accurately resolve both long and short-range hydrodynamic and frictional interactions, particle positioning, whilst maintaining efficient scalability. The open-source CFDEM software package was utilised, allowing for the implementation of custom code for lubrication forces, charge transfer, DLVO theory, and real-time collision tracking. This method was rigorously validated against experimental data and the exact solution of particle motion during short-ranged interactions. With the selected CFD-DEM methodology, we systematically investigate the macroscopic and spatially-resolved particle collision frequency fc, examining the influence of mean particle concentration and roughness . We uncover the mechanisms that govern particle collisions and demonstrate that collision frequency increases with and and also increases with local particle concentration. Local collision frequency maxima are observed within the channel that correspond to shear layers between circulation regions driven by transverse secondary flow. These findings underscore the intricate interplay between local particle concentration and secondary flows in confined flows of complex fluids. Further, particle roughness and the inclusion of lubrication interactions were also noted to strongly influence the total p-p and p-w collisions within the channel. Varied channel geometries were investigated, whereby circular channel geometries posed the highest p-p and p-w collision frequency, although they may be impractical to develop. Low aspect ratio rectangular geometries also demonstrated higher collision frequency results with respect to square channels, indicating their potential as future candidates for testing under charge transfer conditions. Additionally, the impact of electrostatic forces on the particle microstructure and p-p interactions within a fully charged suspension and during the charging of an uncharged suspension was independently examined. By integrating DLVO theory equations into the CFD-DEM model to account for van der Waals and electrostatic double layer forces, the study provided a comprehensive understanding of hydrodynamics, frictional, and electrostatic forces. Electrostatic forces were found to significantly influence particle migration and collision frequency. A smaller double layer length () led to particle migration towards the channel centreline due to van der Waals forces not being effectively screened by double layer forces, creating large clusters and continuously contacting particles. Higher values were observed to significantly reduce particle contacts, and at high charge, wall collisions were diminished to very low values. During the charging of an initially uncharged system, varying charge transfer efficiency (CTEC) values highlighted the variability in charge rate. Higher CTEC values resulted in higher transfer rates and a smoother charge distribution, while lower CTEC values caused particles to migrate away from the wall before receiving significant charge. These results demonstrate both the necessity for accurate information on particle transfer dynamics to ensure an accurate model, and also the requirement when modelling such systems to capture both charge transfer and electrostatic forces in-situ during the simulation.</p
Can Including Cryptocurrencies with Stocks in Portfolios Enhance Returns in Small Economies? An Analysis of Fiji’s Stock Market
No full textThe market for digital assets, and more specifically cryptocurrencies, is growing, although their adoption in small island countries remains absent. This paper explores the potential benefits of integrating cryptocurrencies into portfolios alongside stocks, with a focus on Fiji’s stock market. This is the first study on a small market like Fiji, which emphasizes the role of cryptocurrencies in portfolio management. We analyze the outcomes (returns and risks) of combining cryptocurrencies with stocks using 12 different techniques. We use monthly stock returns data of 18 companies listed on the South Pacific Stock Exchange from Aug-2019 to Jun-2025 (71 months) and nine cryptocurrencies from Sept-2019 to Jun-2025 (70 months). Our main analysis shows that only one cryptocurrency, albeit with a small exposure, consistently appears in the stock-cryptocurrency portfolios in the 12 methods. Using the return-to-risk ratio across methods as a guide, we find that the stocks-cryptocurrencies portfolio based on EQW, MinVar, MaxSharpe, MinSemVar, MaxDiv, MaxDeCorr, MaxRMD, and MaxASR offers better outcomes than the stock-only portfolios. Using high returns as a guide, we find that six out of 12 methods (EQW, MaxSharpe, MaxSort, MaxCEQ, MaxOmega, and MaxUDVol) support the stocks-cryptocurrencies portfolios. Portfolios satisfying both conditions (high return-risk ratio and high return) are supported by the EQW and MaxSharpe portfolios. The consistency of assets in both stock and stock−cryptocurrency portfolios is further confirmed by 24-month out-of-sample forecasts and Monte Carlo simulations, although the latter supports small exposures in two out of the nine cryptocurrencies. Based on the results, we conclude that a small exposure to certain cryptocurrencies can strengthen diversification and improve potential returns.</p
Desegregating Business and Human Rights: Including Due Diligence in the Corporations Act
No full textThe Corporations Act 2001 (Cth) does not currently contribute to legislative efforts to hold companies accountable for human rights harms or to provide remedies for affected individuals. While the United Nations Guiding Principles on Business and Human Rights anticipate a central role for corporate law, international obligations have been implemented outside corporations law. Some jurisdictions – such as France, Germany, and the European Union – have introduced mandatory human rights due diligence (mHREDD) regimes. France embeds these in its corporate code; Germany's regime operates alongside it. However, these reforms remain politically contested, with both the German Act and the EU Corporate Sustainability Due Diligence Directive facing delays. This article considers whether, and in what form, a due diligence obligation could be introduced into Australian corporations law. Drawing on international developments, it proposes a model requiring risk analysis, compliance systems, grievance mechanisms, and remedy access, and considers ASIC's potential role in supervision and enforcement.</p
Engaged journalism in the heartland: understanding regional news audiences
No full textLocal news often serves as the primary source of information about the community and is an essential platform for civic participation. However, the provision of local news in regional Australia is declining, while audience needs are shifting. This report investigates the gap between journalistic norms and audiences’ perception through an empirical investigation of what audiences want from local news and how they might be involved in the production and dissemination of news.
The report pays special attention to visual news given that smartphones are an important part of the local news landscape, both in its production and consumption. To better understand how audience participation can strengthen the relationship with local news media, the concept of engaged journalism was applied.
The study confirms a void in the provision of local news as news organisations struggle to find optimal business models to serve the local community. It also finds that the shift to digital in regional news has enabled a unique news ecosystem where audiences are actively engaged in the generation of news through digital platforms, especially using visual formats.
The report includes key recommendations for the local news industry and stakeholders.</p
Navigating the AI Hype: Chinese Journalists’ Algorithmic Imaginaries and Role Perceptions in Reporting Emerging Technologies
No full textThis study explores how Chinese journalists perceive, use, and report on artificial intelligence (AI) amid the global discourse of AI hype. Drawing on qualitative analysis of 18 in-depth interviews with journalists from a range of Chinese news organisations, this research examines (1) journalists’ algorithmic imaginaries and their role in shaping AI narratives, (2) perceptions of AI hype and strategies for responsible reporting, and (3) the journalistic roles reflected. The findings show that journalists predominantly frame AI as a pragmatic tool for enhancing newsroom efficiency, while also acknowledging its broader societal significance. Although aware of speculative discourses, they reject the label of “media hype,” portraying their coverage as balanced, event-driven, and aligned with public interest. Situated within China’s distinctive political and media environment, this study highlights the complexities of journalistic practice in the algorithmic age and calls for a contextualised theorisation of media hype and AI’s discursive construction in non-Western settings.</p
‘Hurry Up and Get Me out of Here’: The Experience of People Under 65 Years (Still) Stuck in Aged Care
No full textFollowing the Royal Commission into Aged Care Quality and Safety, the Australian Government set a target for no-one under 65 years of age to be living in residential aged care (RAC) by 2025. The numbers of young people in residential aged care (YPIRAC) have significantly declined since the start of the targets. However, most of the reduction can be attributed to death and people turning 65 rather than to people moving into better housing. This qualitative study informed by grounded theory methodology explores the intersection between the housing needs, preferences, and the experience of securing adequate funding, housing, and support to transition out of RAC for nine people with disabilities and six close others. Findings showed that despite having access to funding under Australia's National Disability Insurance Scheme (NDIS), the transition out of RAC was impacted by difficulty securing the right category and amount of funding, unmet housing preferences and inadequate housing and support. The cumulative impact was frustrating, exhausting, limiting, dislocating and ultimately restricting. Policy implications include the need for a skilled workforce to navigate the transition, a responsive approach to housing that considers diverse needs and preferences, and systematic data collection to better inform housing options and supports.</p
An Innovative and Universal Teaching Model in Engineering Education to Foster Industry 5.0 Skills—EPIC Principles
No full textIn light of Industry 5.0’s emphasis on human-centric approaches, future engineering education should prioritise the development of soft skills to complement students’ digital and technological competencies. This paper investigates the in-demand skills for Industry 5.0 and explores pedagogical approaches to foster these skills in engineering students. The identified skill categories include digital and technological proficiency, analytical and critical thinking, creativity and innovation, and communication and interpersonal skills. However, to date, no universal teaching model exists that holistically imparts all these skills. To address this gap, the paper introduces a new universal pedagogical model: the EPIC framework, which integrates Experiential, Paired, Inquiry-based, and Collective learning principles and provides examples of how this framework can be incorporated into engineering curricula to simultaneously cultivate all Industry 5.0 skills. Successfully implemented in engineering courses spanning different academic levels (Year 1 to Year 4), EPIC offers a promising framework for equipping students with the skills essential for thriving in the Industry 5.0 era.</p
Tree removal modelling results - detailed
No full textData and visualisations associated with Landscape and Urban Planning Publication titled "Defining ‘adequate’ tree protection: meeting urban canopy targets requires careful retention of mature trees" by Croeser et al., 2025. </p