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Seasonal Sensitivity Analysis of Ensemble Machine Learning Based Water Quality Predictions to Streamflow Variations: A Case Study of Toowoomba, Queensland, Australia
No full textoai:research.usq.edu.au:1027y4Sustainable surface water quality management requires a thorough understanding of the influence of streamflow fluctuations on water quality across different seasons. The objective of this study is to explore the seasonal sensitivity of previously developed XGBoost-BO ensemble machine learning model to predict Water Quality Index (WQI) using streamflow as the sole input. This study applied Shapley Additive explanations (SHAP) and Partial Dependence
Plots (PDP) to interpret the response of the developed models across four distinct seasons of Australia. The analysis reveals that WQI predictions exhibit varying degrees of sensitivity to streamflow in different seasons indicating critical thresholds during distinct flow events. The novelty of this study lies in its independent contribution of conducting seasonal sensitivity analysis using advanced explainability tools. This study investigates how and why the model responds differently to streamflow variations. The findings reveal season specific threshold, non-linear
behaviors and contrasting flow-response patterns, providing non interpretability insights which are not captured earlier. The findings of the study highlight the significance of season specific interpretation of machine learning models in water quality management particularly under climate variability and provides insight into the perception of hydrological influences on water quality dynamics by the
application of explainable artificial intelligence tools
Potato crop disease prediction in Prince Edward Island using machine learning: A decision support approach for farmers
No full textWhy Was the Official Australian Monsoon Onset Unusually Late in 2024/25?
No full textThe official 2024/25 Australian summer monsoon (ASM) onset occurred on 7 February, more than two weeks later
than the previous record. Defined using Darwin winds, the official ASM typically arrives between mid-December and mid- January. Here, we investigate (1) why the ASM onset was record late, despite La Niña-like conditions, and (2) if the late ASM onset was consistent with other unofficial monsoon and rainy season onset definitions. Our results show earlier onsets when using wind and rainfall-based definitions, mainly due to strong synoptic-to-intraseasonal variability. Two onset definitions were triggered in December 2024 when the Madden–Julian Oscillation (MJO) contributed to deep convection and above-average rain over northern Australia. In late January, a monsoon trough formed over northeast and northwest Australia, but not over Darwin. With the MJO in a suppressed state, the Darwin region experienced record-breaking January temperatures. The ASM eventually arrived in early February, with the reason behind its historically late onset likely a result of weather noise and variability. Another location, ~1200 km east of Darwin, did not experience such a late onset, using similar definitions. Relevant to monsoon systems globally, our study highlights the limitations of local onset or wind-only definitions, which may not necessarily capture the large-scale monsoonal conditions, and be amplified by short- term weather variability
Engaging the disengaged: Investigating the built environment in a secondary FlexiSpace
No full textThe physical space of learning is an essential part of promoting inclusive and supportive learning environments for all students, becoming even more important when students are at risk of educational disengagement and securing future success in life. This article presents findings from a qualitative pilot case study within a Queensland state secondary school in Australia to highlight the teacher voice around elements of the FlexiSpace built environment viewed as valuable in engaging disengaged youth. The interpretivist research approach included teacher reflection journals and semi-structured interviews. Findings illustrate the significance—both positive and negative—of the FlexiSpace built environment on student engagement. Some elements are valued by participants because they facilitate greater flexible, relational, and digital pedagogy—pedagogies positively influencing student engagement. Other elements are not valued—perceived as restricting teaching practice and fostering greater distraction and dysregulation amongst students. The discussion focuses on the impact of flexible configuration and diversity of furniture; the importance of a sense of belonging; and the effectiveness of built elements to catalyse pedagogical flexibility and enhance student-centred learning. Findings from this case study suggest that the physical FlexiSpace built environments alone do not have a positive impact upon student engagement and that school funding in other areas is also crucial. Moreover, investment into education outcomes must be seen as multifaceted including teacher participation within the design process of facilities and collaboration during the initial teaching and learning phase, ensuring pedagogical practice and spatial possibilities match, is critical
Microaggressions, Trauma, and Trauma-informed Education in Higher Education
No full textThis chapter explores the pervasive presence and impact of microaggressions in higher education, focussing on how these subtle, often unintentional, discriminatory actions can impact marginalised groups, including individuals of diverse races, genders, sexualities, disabilities, and socio-economic backgrounds. It begins by tracing the historical origins of microaggression research, highlighting the covert and dehumanising messages these interactions convey. Next, this chapter examines the way that microaggressions manifest in educational settings, such as classrooms and campuses, and the detrimental effect they have on students’ academic achievement, mental health, and social interactions. Through a trauma-informed lens, the chapter discusses how repeated exposure to microaggressions can lead to cumulative harm, including hypervigilance, cognitive depletion, and battle fatigue, with long-term implications for victims’ overall well-being. The chapter argues that recognising microaggressions as a form of trauma is essential for understanding their deep impact, and advocates for trauma-informed practices in higher education to mitigate these effects. By implementing policies, fostering cultural competency, and creating inclusive learning environments, educational institutions can address the systemic issues that perpetuate microaggressions, ultimately supporting students. The chapter calls for a shift from focussing solely on identifying microaggressions towards understanding how students in higher education settings are harmed by historical and current microaggressions. We encourage institutions to create safer, more inclusive spaces that will allow all students to succeed academically and socially
Integrating recycled waste materials in cementitious grouts: evaluating mechanical integrity and rheological behaviour
No full textConventional cementitious grouts, widely used for underground reinforcement and structural repair, rely heavily on Portland cement, a material responsible for nearly 7% of global CO₂ emissions and significant resource depletion. Addressing this environmental and material-efficiency challenge, this study develops and evaluates novel sustainable grout formulations that partially replace cement with recycled waste glass (WG), tyre rubber waste (TRW), and construction and demolition waste (CDW). By systematically linking mechanical, rheological, and microstructural performance, the research bridges a key gap between sustainability-driven material substitution and the performance requirements of practical grouting applications. Grout mixtures incorporating 0–20% WG, 0–3% TRW, and 0–10% CDW were evaluated for rheological behaviour and unconfined compressive strength (UCS). All modified grouts maintained shear-thinning properties but exhibited significantly reduced viscosity, enabling lower water demand. Notably, WG-enhanced grouts preserved or even improved UCS. For example, 2.5–5% WG substitution resulted in minimal strength loss, yielding up to 97% of the 70.5 MPa control strength. When adjusted for reduced water content, these mixes achieved a 10.6% UCS increase. TRW grouts peaked at 55.2 MPa with 0.75% inclusion, while CDW caused only minor strength drops at 2.5–5%. Enhanced flowability (lower viscosity/yield stress) compensated for some strength reductions. Microstructural analysis revealed that WG improved matrix density via pozzolanic activity and filler effect, while TRW and CDW influenced pore structure. Beyond their laboratory performance, these findings underscore the practical potential of recycled waste-based grouts to reduce cement consumption, lower embodied carbon, and divert waste streams from landfills. Such formulations retain pumpability and mechanical performance while offering viable alternatives for ground reinforcement, structural repair, and sustainable construction applications. Overall, the integration of WG, TRW, and CDW demonstrates a promising pathway toward lower-impact cementitious grouts that meet both engineering and environmental demands
B-site Cu-doped PrBa0.5Sr0.5Co2O5+δ as novel low temperature-solid oxide fuel cells cathodes with reduced thermal expansion coefficient and enhanced oxygen-ion diffusion
No full textPrBa0.5Sr0.5Co2O5+δ (PBSC) has attracted considerable attention as a layered perovskite cathode for solid oxide fuel cells (SOFCs) due to its favorable electrochemical properties, while also holds significant potential for modification into an efficient low-temperature cathode. However, its high thermal expansion coefficient and sluggish oxygen-ion diffusion remain critical challenges for achieving stable operation of SOFCs at reduced temperatures (below 650 °C). To overcome these limitations, we employe first-principles calculations to screen the suitable B-site dopants (M = Fe, Ni, Cu) for PBSC, aiming to optimize its structural and electrochemical characteristics. Guided by these theoretical insights, a series of PrBa0.5Sr0.5Co2-xCuxO5+δ (x = 0, 0.5, 1.0) cathode materials were synthesized and systematically investigated with respect to their phase structure, elemental valence states, thermogravimetric properties, and microstructure. Among the tested dopants, Cu substitution proves to be the most effective in enhancing the electrochemical performance of PBSCCx cathodes, owing to the rigid Cu-O coordination and suppressed Co redox that limit lattice expansion, progressive lattice contraction upon Cu incorporation, and enriched oxygen vacancies that facilitate oxygen ion transport. Consequently, the PBSCC1.0 cathode manifests a more than 24 % reduction in thermal expansion coefficient, a 29 % decrease in polarization resistance, and an 8 % drop in activation energy compared to undoped PBSC, highlighting the effectiveness of Cu doping in optimizing cathode properties. Furthermore, the single cell employing PBSCC1.0 cathode could achieve a peak power density of 0.222
Mapping the Transition to Automotive Circularity: A Systematic Review of Reverse Supply Chain Implementation
Full text linkThe automotive industry’s shift to a Circular Economy for global sustainability is vital, but it faces challenges when establishing efficient Reverse Supply Chains. Reverse Supply
Chain implementation is dependent on multiple barriers and enablers, including economic, managerial, technological, regulatory, and social domains, thus making single-factor solutions ineffective. The purpose of this review is to conduct a systematic literature review to understand how these interconnected barriers and enablers can collectively shape Reverse Supply Chain implementation and performance, specifically within the automotive sector, which remains little known. The PRISMA framework was utilised, which resulted in 129 peer-reviewed articles being selected for review. Findings showed that the literature focuses primarily on Electric Vehicle batteries within developing economies, particularly China. Reverse Supply Chain implementation is governed not only by isolated barriers but by complex systemic interdependencies between enablers as well. This complex interrelationship between barriers and enablers can be categorised into five key dimensions: economic and financial; managerial and organisational; technological and infrastructural; policy and regulatory; and market and social. The study reveals two systemic patterns driving the transition: technology–policy interdependence and the conflicting relationship between large-scale production and value extraction. Our findings also presented a research agenda focusing on strategic value creation through material streams of automotive electronics, plastic, and composites with high potential value, and further insights are needed in regions such as the Middle East, Oceania, and the Americas. Organisations should consider Reverse Supply Chain as a strategic approach for securing critical material supplies, while policymakers could leverage the use of digital tools as the foundational infrastructure for subsidies allocation and prevent fraud
Navigating the complexities of healthcare costs in Bangladesh: A closer look at environmental quality, economic growth, energy use, industrialization, urbanization, and forest area
No full textBangladesh is grappling with the challenge of balancing public health with pollution reduction. The current research seeks to analyze the relationships between ecological indicators and health expenditure and to provide policy suggestions to enhance environmental conditions and minimize healthcare costs. The investigation explored various elements, such as carbon dioxide (CO2) emissions, gross domestic product (GDP), the use of fossil fuels and renewable energy sources, industrialization, urbanization, and forest areas. The dynamic ordinary least squares (DOLS) approach was used to explore time series data from 2000 to 2022, and the results revealed that every 1 % increase in CO2, GDP, industrialization, urbanization, and consumption of fossil fuels increased long-term health expenditures by 1.45 %, 0.38 %, 1.39 %, 0.91 %, and 1.04 %, respectively. Instead, a 1 % expansion in forest area and renewable energy use would reduce health expenditures by 1.91 % and 0.48 %, respectively. To test the robustness of the model, canonical cointegrating regression (CCR) and fully modified ordinary least squares (FMOLS) estimation techniques were incorporated. The findings offer policy recommendations for Bangladesh to reduce pollution and ensure the sustainability of the environment and healthcare facilities. These outcomes are valuable for generating a preventive health plan to combat the growing health effects of environmental pollution in Bangladesh