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Multi-objective Optimisation for Existing Houses Retrofit Targeting Net Zero Energy: Framework and Application in Victoria, Australia
No full textEnergy efficiency retrofitting of existing buildings, including housing, plays a critical role in enhancing thermal comfort, reducing energy consumption, utility costs, and associated greenhouse gas (GHG) emissions. Despite these benefits, the energy efficiency of existing homes in Australia built before the mid 2000’s remains low, with an average rating of 1.7 stars (on a scale of 0- worst to 10- best) compared to the 7 star-rating required for new homes in states such as Victoria. While there have been attempts by policy makers and some homeowners to increase the level and depth of retrofit being undertaken in Australia, the progress falls short of what is required for a low carbon future and a number of barriers to increasing energy efficiency and adopting low-emission technologies persist. Part of the challenge for scaling up retrofit is the lack of clear information available about how to deliver retrofit across competing priorities such as investment cost and greenhouse gas emissions reduction.Residential buildings account for 8.6% of total energy consumption, 24% of electricity use, and over 10% of emissions in Australia. The majority of Australian homes were constructed before the implementation of minimum energy performance requirements, which means they were designed and built without adequate consideration for climate adaptation and energy efficiency. While recent regulations have introduced and raised minimum energy and performance requirements, existing homes remain exempt from any minimum requirements. Research indicates that retrofitting existing homes is more effective at reducing greenhouse gas emissions than demolition and reconstruction. With the majority of current Australian homes expected to remain in use in 2050, this presents an urgent national challenge requiring immediate attention if wider sustainability goals are to be achieved.Many previous energy retrofit projects have focused on individual measures or “quick” retrofits, which have been difficult to scale up to other retrofit activities or apply to different building archetypes, and few have targeted the ultimate goal of achieving net zero energy outcomes. This study addresses this challenge by developing a comprehensive framework to balance financial constraints with environmental goals with the overarching aim of achieving net zero energy consumption. The main question for this thesis focuses on how multi-objective optimisation can be used to support optimal selection strategies under multiple constraints such as minimising energy demand, investment cost, and greenhouse gas emissions for existing Australian housing.This research presents a 5-step, 3-phase framework that integrates simulation-based multi-objective optimisation using the active archive Non-dominated Sorting Genetic Algorithm II (aNSGA-II) with different decision-making methods to identify optimal residential retrofitting strategies and determine the final trade-off solutions. The framework simultaneously optimises thermal energy demand, investment cost, and greenhouse gas emissions. Developed in Python and coupled with EnergyPlus via the DesignBuilder interface, the framework evaluates a wide range of retrofit options, including building envelope upgrades, heating, ventilation, and air conditioning system improvements, indoor shading, and renewable energy integration. The model was applied to a dominant house type – detached housing – in Australia, testing 24 construction variations in the Melbourne climate zone. Best performance results were found to lift performance from 0 stars to 3.5-4 Star rating. The trade-off results reveal substantial performance gains, with an average 64% improvement in energy efficiency and up to a 78% reduction in greenhouse gas emissions achievable within a retrofit investment of AUD 20,000. The comprehensive multi-objective optimisation-based framework developed in this thesis can be used to evaluate energy demand savings, greenhouse gas emissions reduction potential under investment restrictions across various housing archetypes, as well as in other climate zones. Application of this framework to various housing types can provide policymakers with a robust basis for evaluating the potential for energy improvements and greenhouse gas emissions reduction and serve as a foundation for developing a bottom-up approach to estimate overall retrofit performance. This implication can be applied not only to Australia but also to other countries, contributing to global energy savings and greenhouse gas emissions reduction targets.The outcomes of all RBs in this thesis can help policymakers better understand the potential for performance improvement and define new energy codes and standards for existing housing retrofits in Victoria, Australia. The optimised results are better than the outcomes of previous retrofitting projects in Australia, however, the findings in this thesis remain well below the minimum requirement of 7 stars for new houses in Victoria, indicating that if the government aims to retrofit existing houses to an equivalent minimum star level for new houses, more efficient retrofitting measures should be considered. The results also support recommendations to classify different star-rating targets for retrofitted house energy performance according to the pre-retrofit performance of existing houses, rather than applying a one-size-fits-all regulation to all existing houses. Such approaches used in previous projects were found insufficient to improve all existing houses to the same energy performance level whilst original star ratings differed substantially. Given multiple optimal alternatives tailored to the needs of different stakeholders, this framework can provide the flexibility required by the “performance-based” energy code and benefit private homeowners specifically by offering more transparent information and a wider range of retrofitting package options. The outcomes also provide homeowners with clear insights into the value of their investment in retrofitting options. This creates a win–win situation to which environmental benefits align with government targets, while investment considerations address homeowners’ primary concerns. Such flexibility can further encourage the adoption of retrofitting measures in the residential sector.This thesis offers actionable insights for policymakers, and private homeowners, underscoring the economic feasibility and environmental benefits of retrofitting Australia's existing housing stock to support national carbon reduction targets.</p
Enhanced Cardio Care: Explainable Vision Transformer Multimodal Pipeline For Cardiac Abnormalities Detection Using Electrocardiogram Image Reports
No full textDuring disasters, a large volume of messages are posted on social networking services (SNS). Some of these messages contain behavioral facilitation information, which either encourages or discourages specific actions. However, the interpretation of such information depends on the personality traits of the individuals affected. In this study, we hypothesize that victims’ personality traits influence their perception of behavioral facilitation information, and we analyze the characteristics of these differences. Focusing on typhoons, we propose a method for extracting behavioral facilitation information from posts on X (formerly Twitter) during typhoon-related disasters. The extracted information is then classified into four contentbased categories: suggest, inhibition, encouragement, and wish. Furthermore, we categorize individual personality traits into five dimensions (the Big Five), and also take into account their age and sex. We then analyze how the perception of each type of behavioral facilitation information varies according to these traits. Our analysis reveals that, during disasters, the interpretation of behavioral facilitation information exhibits distinct and consistent patterns depending on the personality traits of the victims.</p
Technological Change and Job Quality of Managerial Work: A Labour Process Theory Perspective in the Context of the Australian Transport and Logistics Sector
No full textAdopting a labour process theory (LPT) approach, this research investigates how managers experience the impact of digital technologies on their job quality and which particular technologies impact on job quality of management work. While LPT has traditionally been used to focus on work degradation of labour, studies exploring the same for managers is scarce
(Narayan 2023; Willmott 1997:196). It is idiosyncratic that despite the centrality of managers and managerial discourse (Cunliffe 2014) and the overarching implications of management done ‘badly’ (Korica et al. 2017), the last dedicated reviews into studying managerial work were 30 years back (e.g.Hales 1986; Willmott 1987). During this period, managerial work has been subject to significant changes (Worrall et al. 2016), particularly with the recent emergence of algorithmic management (Jarrahi et al. 2021). Despite these developments, the impact of such technological changes on managerial work remains unclear (Foster et al. 2019). Previous studies relied on quantitative, survey-based analysis which provided useful data, however, studies using qualitative approach have been limited (Hassard and Morris 2022).
This study adopted a qualitative research methodology where data was collected from 30 semi structured interviews with transport and logistics managers. The findings reveal paradoxical experiences. On the one hand, managers elaborated how technology had exacerbated characteristics typically associated with ‘bad jobs’ (Adamson and Roper 2019; Clarke 2015; Pocock and Skinner 2012; Warhurst et al. 2017) such as rising work intensification and extensification, reduced autonomy as well as technical and conceptual deskilling. Conversely, they also expounded how technology had simplified work for themselves, provided greater flexibility and control of work, and created opportunities for upskilling and enhanced job security, all characteristics associated with ‘good jobs’ (Osterman and Shulman 2011). Findings also highlight smartphones; smartphone-enabled work apps and team collaboration apps such as MS Teams as the dominant technologies impacting on job quality of managerial work. Yet another emergent and implicit finding is that subsectors within the transport and logistics sector have no significant impact on the experience of managerial job quality. The study suggests that the conceptualisation of job quality of managerial work within the context of technological change is incomplete without considering the aspect of managing the team. The study contributes to wider debates on the impact of new and emerging technologies on the future of work and specifically on its impact on job quality. The study also contributes as one of the few studies within the LPT tradition exploring the experience of managerial job quality as a
consequence of technological change.</p
Queer Generations: LGBTQ Growing Up, Belonging and Sexual Citizenship
No full textQueer Generations offers a groundbreaking study of sexual citizenship, based on the coming of age narratives of two social generations of LGBTQ people in Australia.The open access book's assembly and analysis of narrative accounts demonstrates the differences contained in people's experiences of LGBTQ youth sexual citizenship. It is the first book to provide a robust empirical account of the diverse ways in which sexual citizenship is experienced and understood by different social generations of LGBTQ people growing up. By so doing, Queer Generations offers a unique analysis of ongoing contestations over the place of sexual and gender diversity in relation to citizenship.</p
An Entropy Measure of Knowledge Evolution
No full textThis paper proposes Conceptual Knowledge Entropy, a network-based metric for quantifying the
convergence of conceptual relationships in scholarly literature. Grounded in the entropy literature,
Conceptual Knowledge Entropy assesses the probability distribution of relationship paths to a
dependent concept, with higher values indicating greater theoretical agreement. We also introduce
Conceptual Knowledge Entropy Sensitivity to examine the influence of individual publications and
antecedents on conceptual convergence. We demonstrate the application of this measure using the MISQ Curation dataset. This study contributes to the development of quantitative measures for evaluating scholarly knowledge. We discuss and outline future research directions to refine and extend the application of this measure.</p
Re-using co-design in initial teacher education: A scoping study to inform school-university partnerships
No full textCo-design as an effective tool in supporting partnerships is experiencing a renaissance in contemporary Initial Teacher Education (ITE) policy reform. While not a new construct, the current re-use of co-design represents a contemporary shift in collaboration, emphasising inclusivity and adaptability by integrating critical thinking and problem-solving with content and pedagogy. Despite its growing popularity, co-design's potential in supporting diverse partnerships remains largely unexplored. This study delves into the complexities, opportunities, and challenges of co-design as a tool in reshaping ITE. The scoping study follows a five-stage process: identifying the research question, identifying relevant studies, study selection, data charting, and summarising results. The process culminated by highlighting five papers that illustrate co-design's importance, including collaboration, trust, shared values, dialogue, power dynamics, and open communication, in ITE. The discussion highlights key considerations in co-design within ITE. These include the scarcity of literature on co-design, the necessity for terminology consensus, the importance of genuine collaboration, and the learner-focused improvement potential of co-design. This research has implications for partnership policy and proposes that significant changes are needed to accommodate innovations in ITE co-design.</p
Development and Validation of Chronic Epilepsy Models using Zebrafish as an Alternative to Rodents
No full textEpilepsy is a chronic neurological disorder marked by recurrent seizures and significant comorbidities including cognitive impairment, anxiety, and depression, which collectively reduce the quality of life in affected individuals. Despite decades of research and the development of numerous antiepileptic drugs (AEDs), approximately 25% of patients remain unresponsive to current therapies. The limitations of existing AEDs are often attributed to the lack of robust preclinical models that closely mimic the complex pathophysiology of chronic epilepsy observed in humans. Traditional acute seizure models such as pentylenetetrazole (PTZ) and maximal electroshock seizure (MES) tests in rodents, while useful for initial drug screening, fail to replicate the chronic progressive nature of epilepsy and its associated comorbidities. Additionally, the high cost and limited genetic manipulability of rodent models pose challenges for large-scale therapeutic screening. These gaps highlight the urgent need for alternative models that are cost-effective, genetically tractable, and suitable for studying both seizures and comorbid conditions.In recent years, zebrafish (Danio rerio) have emerged as a promising vertebrate model in neuroscience research including epilepsy. Zebrafish offer several advantages like small size, low maintenance costs, high reproductive rate, transparent embryos, conserved brain structure, neurotransmitter systems and the ability to perform high-throughput pharmacological screening. Both larval and adult zebrafish exhibit seizure-like behaviors and electrographic activity in response to various chemoconvulsants, making them suitable for modeling epilepsy. However, most zebrafish studies have focused on acute seizure paradigms, and the development of validated chronic epilepsy models remains limited. Furthermore, epilepsy is not only characterized by seizures but also involves a spectrum of comorbidities that must be addressed for effective clinical management. Yet, few preclinical models integrate seizure activity with behavioral and cognitive impairments.This thesis aimed to develop and validate chronic epilepsy models in zebrafish, assess associated behavioral and cognitive comorbidities, and design & validate scalable tools for neurobehavioral screening. The study focused on both adult and larval stages of zebrafish to provide a comprehensive and translational model for epilepsy research. Initially, efforts were made to establish a chronic seizure model in 7 days post-fertilization (dpf) zebrafish larvae using repeated PTZ exposure. However, the use of 1-phenyl 2-thiourea (PTU) for depigmentation significantly reduced seizure-like activity and locomotor responses in larvae, indicating potential anticonvulsant properties of PTU. This finding emphasized the importance of carefully controlling depigmentation protocols in larval behavioral studies. Due to these limitations, the chronic seizure model was subsequently developed in adult zebrafish.Among the chemoconvulsants evaluated, pilocarpine was associated with high mortality and immediate increase in seizure score upon administration, making it unsuitable for chronic modeling. In contrast, repeated exposure to a subconvulsive dose of PTZ (1.25 mM) for 22 consecutive days successfully induced a chronic kindling state in 66.66% of adult zebrafish without causing mortality. This model exhibited stable and reproducible seizure behavior and was pharmacologically validated using valproic acid (VPA). VPA, when administered as a pre-treatment, effectively prevented the development of kindling and significantly reduced seizure severity when given post-kindling. Molecular validation further supported the model’s reliability. The gene expression analysis revealed elevated levels of immediate early gene c-fos and transcriptional coactivators crebbpa and crebbpb along with a disrupted glutamate to GABA ratio, all of which were reversed by VPA treatment.The validated PTZ-kindling model was then used to study epilepsy-associated cognitive and behavioral comorbidities. In a T-maze task, kindled fish displayed significant deficits in learning and memory, whereas social memory appeared largely preserved. However, kindled fish showed reduced exploratory behavior and increased social disengagement. Neurochemical analysis demonstrated abnormally elevated levels of dopamine and serotonin in the brains of kindled fish. In parallel, key genes related to dopaminergic and cholinergic signaling (npy, drd1b, drd2b, th, and chrna5) were downregulated, suggesting a link between altered neurotransmission and cognitive dysfunction.Therafter, behavioral comobidities were assessed using the novel tank test (NTT) and light-dark preference test (LDPT). PTZ-kindled fish spent more time in the upper zone of the NTT and preferred the dark zone in the LDPT, indicating impaired habituation and heightened anxiety. Social preference assays further revealed reduced social preference towards shoal by the kindled fish. At the molecular level, genes related to neuroplasticity and mitochondrial function (bdnf, ppp3r1a, vdac3, and prohibitin2) were downregulated while slc25a5 was upregulated. Western blot analysis showed significantly elevated pCREB levels with unchanged total CREB expression, indicating enhanced CREB phosphorylation and altered gene transcription. These findings demonstrate that the PTZ-kindled zebrafish model exhibits not only chronic seizures but also significant behavioral and molecular alterations associated with epilepsy comorbidities.To extend neurobehavioral assessments to early developmental stages, a custom-designed behavioral apparatus was developed for zebrafish larvae. Using laser cutting and thermal bonding techniques, a low-cost and flexible multi-well PMMA plate was fabricated for high-throughput behavioral assays. Two protocols, tapping and top blue light flash, were optimized and validated for assessing seizure-related and anxiety-like responses in 7 dpf larvae. Larvae exposed to 5 mM PTZ from 5 to 7 dpf showed significantly reduced total distance moved and increased freezing responses, confirming the apparatus’s sensitivity and reliability in detecting seizure-induced behavioral impairments.In conclusion, this thesis establishes robust and reproducible zebrafish model for chronic epilepsy and its associated cognitive and behavioral comorbidities. The PTZ-kindling model in adults provides a reliable platform for antiepileptic and antiepileptogenic drug screening, while the newly developed larval behavioral system enables scalable testing in early developmental stages. Together, these tools offer translational relevance and address key limitations of traditional rodent models, supporting broader adoption of zebrafish in epilepsy research, neurobehavioral studies, and drug discovery.</p
A Parameter Sensitivity Analysis of Two-Body Wave Energy Converters Using the Monte Carlo Parametric Simulations Through Efficient Hydrodynamic Analytical Model
No full textThis paper introduces a novel approach by employing a Monte Carlo simulation to investigate the impact of various design parameters on the performance of two-body wave energy converters. The study uses a simplified analytical model that eliminates the need for complex simulations such as boundary elements or computational fluid dynamics methods. Instead, this model offers an efficient means of predicting and calculating converter performance output. Rigorous validation has been conducted through ANSYS AQWA simulations, affirming the accuracy of the proposed analytical model. The parametric investigation reveals new insights into design optimization. These findings serve as a valuable guide for optimizing the design of two-body point absorbers based on specific performance requirements and prevailing sea state conditions. The results show that in the early design stages, device dimensions and hydrodynamics affect performance more than the PTO’s stiffness and damping. Furthermore, for lower frequencies, adjustments to the buoy’s height emerge as a favorable strategy, whereas augmenting the buoy radius proves more advantageous for enhancing performance at higher frequencies.</p
Metal organic framework derived In2O3/ZrO2 heterojunctions with interfacial oxygen vacancies for highly selective CO2-to-methanol hydrogenation
No full textThe hydrogenation of CO2 to methanol is a promising route for carbon capture and utilization, however achieving high selectivity and productivity remains a challenge. This study presents a novel catalyst synthesized by pyrolyzing a zirconium-based metal-organic framework impregnated with indium, yielding ultrafine In2O3 nanoparticles uniformly embedded within a ZrO2 and carbon matrix. The resulting In2O3/ZrO2 heterojunction exhibited abundant oxygen vacancies at the interface, which is crucial for enhancing the catalytic performance. Under gas-phase conditions, the catalyst achieves an exceptional methanol selectivity of 81% with a record-high productivity of 2.64 gMeOH·gcat⁻¹·h⁻¹ at mild reaction conditions, while in liquid-phase hydrogenation, methanol selectivity reaches 96%. Comprehensive structural characterizations confirmed that oxygen vacancies and the heterointerface served as active sites, facilitating CO2 activation and methanol stabilization. Mechanistic insights from in-situ DRIFTS and ATR-IR spectroscopy revealed that methanol formation proceeds via the formate pathway, further supported by in-situ ambient-pressure X-ray photoelectron spectroscopy, demonstrating electronic structural modulation and an increased concentration of oxygen vacancies. These findings underscore the critical role of defect engineering in optimizing CO2 hydrogenation catalysts and provide a pathway for designing highly efficient systems for sustainable methanol production.</p
Increasing airflow ventilation in a nasal maxillary ostium using optimised shape and pulsating flows
No full textVentilation of the maxillary sinus is essential for regulating pressure, preventing infection and providing mucous to the nasal anatomy. During infection, the pathway between the sinus and the nasal airway (ostia) can become inflamed and restrict ventilation. Surgery is often required to restore airflow. The current surgical standard involves the widening of the ostium. Although this restores fluid flow, it has been linked to post-surgical sequelae. This study examined the effects of pulsating flow and geometric modifications on airflow distribution in a T-junction model analogous to a nasal maxillary ostium. A circular T-junction with variable anterior and posterior radius of curvature (Rc) was used to simulate airflow through the nasal maxillary ostium, investigating flow behaviour under oscillatory inlet velocities at frequencies of 30, 45, 60, and 75 Hz. Computational fluid dynamics (CFD) simulations assessed how flow distribution through the nasal cavity and maxillary ostium (represented by the x- and y-branches) is affected by curvature and oscillatory frequency, focusing on implications for respiratory airflow, particle delivery and inhalation toxicology. Results indicated that increasing the anterior Rc enhanced airflow into the y-branch (analogous to the maxillary ostium), while posterior curvature had minimal impact. Higher oscillatory frequencies increased reverse flow, which may improve ventilation but could interfere with consistent drug delivery. These insights are valuable for optimising respiratory therapies and inhalation toxicology.</p