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An Analysis of the European Union’s Illegal, Unreported and Unregulated Fishing Regulation: Impact of the EC Carding System on the Laws and Practices of Third Countries
No full textThe abstract for this item has not been populated.</p
The quiet voices of French territories in tuna fisheries management
No full textGlobal geopolitics heavily influences international fisheries management. It also influences the engagement of fishing nations within regional fisheries management organisations (RFMOs). This is especially true for participating territories. In this paper, we assess the participation and representation of French Overseas Countries and Territories (OCTs) and Outermost Regions (ORs) within two major tuna RFMOs: the Indian Ocean Tuna Commission (IOTC) and the Western and Central Pacific Fisheries Commission (WCPFC), through an equity lens. The article provides an overview of the legal status of these territories under EU law and their roles in the conservation and management of tuna fisheries, by employing Bennett's equity framework to assess their involvement across various dimensions of ocean equity. By highlighting the strategic importance of these regions for France and the EU, the article underscores the necessity for a more equitable approach in integrating OCTs and ORs in tuna RFMOs, ensuring that their specific needs and contributions are acknowledged and valued in regional fisheries governance.</p
A comprehensive study of multiscale pore structural characteristics in deep-buried coals of different ranks
No full textThe pore structure characteristics of coal significantly influence its gas adsorption and desorption capacity, as well as gas migration, playing a crucial role in the development of coalbed methane and the management of gas-related disasters. To investigate the pore distribution characteristics of coal in-depth, pore data for coal samples with varying degrees of metamorphism were obtained using low-pressure nitrogen adsorption (LPGA-N2), low-pressure CO2 adsorption (LPGA-CO2) methods, and mercury intrusion porosimetry (MIP). Multiscale pore size distributions were constructed for three types of coal samples. By combining Scanning Electron Microscopy (SEM) and the Pore-Crack Analysis System (PCAS), which derived SEM images, pore numbers, pore area, heterogeneity coefficient, curvature coefficient, fractal dimension, and porosity data, a quantitative analysis of the multiscale pore distribution characteristics of the three coal samples was conducted. The results indicate that multiscale pore size distribution diagrams are an effective method for studying the multiscale pore characteristics of coal, allowing for quantitative investigation of pore distribution characteristics at different scales. YW coal exhibited the highest micropore content (0.0723 cm3/g), followed by DLT (0.0333 cm3/g) and JG (0.0205 cm3/g). For mesopores, JG had the highest content (0.0182 cm3/g), and for macropores, DLT had the largest volume (0.627 cm3/g). This comprehensive analysis enhances the understanding of coal’s multiscale pore structure and its intrinsic link to adsorption properties. This research is significant for further understanding the pore structure characteristics of coal and revealing the intrinsic link between coal pore characteristics and adsorption properties. The findings are crucial for developing more effective gas drainage schemes, improving gas management in coal mines, ensuring safe production, and reducing greenhouse gas emissions.</p
An Investigation of Psychosocial Risk Management in Teaching
No full textThere is little doubt that teaching, as a type of work, can be both rewarding and hazardous. However, little has been done to interrogate teachers’ perceptions of work, or to identify the psychosocial hazards that may be inherent in teachers’ work or work system. The question of whether teachers are sufficiently able to recognise a work-related hazard is particularly relevant in relation to schools as workplaces.This thesis employs a mixed method multiphase exploratory approach to investigate teachers’ perceptions of work, hazard, and safety. Three studies were conducted with an industry cohort using interviews, focus groups, and an anonymous online survey. Results indicated that regardless of school sector or location, teachers experience and can recognise relational, organisational and systemic factors that impact on their capacity to carry out their duties. Despite this, teachers do not refer to them as psychosocial hazards without prompting.Similarly, despite the presence of teacher workload studies in the teaching literature, workload, and other psychosocially hazardous aspects of teachers’ work (such as lack of autonomy and time pressures), are rarely characterised as hazardous or framed as hazards. When viewed through a work-related safety lens, the implications for recognising these factors as potential psychosocial hazards becomes significant. This is because a work-related safety lens recognises hazardous aspects of teachers’ work such as workload, behaviour management, and time pressures as psychosocial hazards and labels them as such. It is argued that doing so reveals the important role played by language and the recognition of psychosocial hazards in the risk management process in schools.Review of WHS priorities in NSW with consideration of the relevance for teaching illustrates how this thesis provides critical evidence to inform the gap between what is known about work, hazardous work, and the teaching profession. Recognising and labelling hazardous aspects of teachers work as hazards underscores the need to evaluate psychosocial risk management strategies used in school settings in future research. It also draws attention to the value of using the language of WHS in school settings.</p
Firms' Strategic Management in the Face of Climate Risk and Catastrophic Natural Disasters
No full textThis thesis consists of three empirical studies in the area of climate finance, examining firms’ strategic management to cope with emerging climate risks.The first study employs catastrophic natural disasters as adverse shocks to firms’ operations to investigate firms’ post-disaster corruption behaviours. On average, catastrophic natural disasters lead to a 47.4 per cent increase in corruption fees paid by affected firms. Such an increase in corruption payments enables affected firms to offset the reduction in government assistance following natural disasters. However, the relationship between natural catastrophes and firm-level corruption is weaker for firms with political connections, a history of high tax avoidance, and located in provinces with strong local governance.The second study explores whether corruption lubricates firms’ access to credit in the aftermath of catastrophic natural disasters. Using a robust stacked difference-in-differences approach centred around natural disaster events, I find that firms engaging in corrupt activities during the post-disaster period tend to face lower credit constraints than their non-corrupt counterparts. Further analysis reveals that politically connected firms have a distinct advantage in securing vital credit resources during catastrophic natural disasters through their engagement in corruption practices.The third study uncovers whether aggressive CEOs reduce corporate carbon emissions in response to the heightened climate regulatory risks associated with the finalisation of State Climate Adaptation Plans (SCAP) across different U.S. states. The findings show that firms led by more aggressive CEOs decrease carbon emissions after the SCAP finalisation, primarily through adopting carbon emission reduction policies. Moreover, the link between CEOs' aggressiveness and corporate carbon emissions is stronger in firms with more powerful CEOs, located in collectivist states, and facing lower SCAP uncertainty. Interestingly, while firms with more aggressive CEOs reduce carbon emissions, their efforts are not reflected in ESG ratings because these CEOs are less likely to make public commitments to emit less. This paradoxical finding suggests that firms led by more aggressive CEOs are less inclined to engage in greenwashing behaviour.</p
Measuring sustainability in social enterprises: Development and validation of a multi-dimensional framework
No full textSocial enterprises (SEs) are instrumental in achieving the Sustainable Development Goals (SDGs) by addressing persistent social, environmental, and economic challenges. However, the lack of validated frameworks to measure SE sustainability limits their ability to measure and strengthen their sustainable performance, which further hinders the capacity to drive transformative change as intended by the SDGs. Hence, this study aims to develop and validate a multidimensional scale for measuring the sustainability performance of SEs, enabling them to realise their potential and enhance their contributions to the SDGs. This study utilized (Churchill, 1979) three-phase methodology to develop and validate sustainability performance measurement scale for SEs. Phase 1 identified sustainability-related items through a literature review and qualitative analysis, finalized by an expert panel. Phase 2 refined these items using exploratory factor analysis (EFA) on 149 SEs (sample 1) data. Phase 3 validated the structure with confirmatory factor analysis (CFA) on data from 435 SEs (sample 2). The final scale included 36 items across five dimensions: social, economic, environmental, political, and governance, subject to the validity and reliability of the newly developed scale. Reliability was confirmed, with Cronbach's alpha exceeding 0.7 for all dimensions. Convergent validity was supported by AVE scores above 50 %, while HTMT ratios below 0.85 established discriminant validity. This research significantly contributes to the literature on SE sustainability by providing a validated performance measurement tool, which enables SEs to optimize their operations, strengthen their impact, and contribute more effectively to the SDGs.</p
High Gain Antennas for Communication between CubeSat and Ground Station
No full textCubeSatellites, often referred to simply as CubeSats, have become game-changers in satellite technology, typically shaped like a cube with each side measuring 10 centimeters (i.e., 1U). CubeSats are a cost-effective and easy-to-use way to engage students in hands-on space projects. Their compact size, and standardized form factors (1U, 2U, 3U, etc.) quickly attracted the attention of the global aerospace industry, researchers, universities and governments. CubeSats have since become platforms for a wide range of scientific, commercial, and educational missions, providing a cost-effective and rapid path to space for a variety of purposes. They are proposed for a variety of applications, such as scientific research, Earth observation, telecommunications and technology demonstrations. Additionally, CubeSats can communicate with each other and form a swarm to perform a wide area measurements and sensing. In order to support all aforementioned capabilities, CubeSats requires high gain, wideband and small antennas for establishing the communication links with each other and with the ground station. However, the limited available space and weight of CubeSats poses significant challenges for any antenna design. These antenna designs need to be small, lightweight while providing good radiation performance (i.e., high gain, and wide bandwidth).This thesis, therefore, provides the first comprehensive and extensive study of all existing antenna designs that are proposed for CubeSat applications, focusing on proposed and used approaches and techniques to achieve wide bandwidth, high gain, circular polarization and small size. The study focuses on different antenna types with different operating frequency bands. It reviews 49 antenna designs, which include 18 patch antennas, 5 slot antennas, 4 dipole and monopole antennas, 3 reflector antennas, 3 reflectarray antennas, 6 helical antennas, 2 metasurface antennas and 3 millimeter and sub-millimeter wave antennas, 1 inflatable reflector antenna, 1 horn antenna, 2 Yagi-Uda antennas and 1 meanderline antenna. The current CubeSat antenna design challenges and design techniques to address these challenges are discussed. These antennas are classified according to their operating frequency bands, e.g., VHF, UHF, L, S, C, X, Ku, K/Ka, W and mm/sub-mm wave bands and an extensive qualitative comparison is provided. Moreover, the suitability of different antenna types for different applications as well as the future trends for CubeSat antennas are also presented. It was found that microstrip patch, and slot antennas are good candidates for CubeSats as they are cheap, have a low profile, are lightweight, and are easy to fabricate. However, their main limitations are low gain and narrow bandwidth.Henceforth, this thesis proposes a wideband metal-only F-shaped patch antenna for CubeSats. The proposed antenna consists of an upper patch, a folded ramp-shaped patch and shorting pins connecting the radiating element with the ground plane. The key idea of using the folded patch technique is to generate the second resonant frequency and hence achieve a wide impedance bandwidth. The −10 dB bandwidth is increased. Moreover, three shorting pins are placed between the upper patch and the ground plane to achieve miniaturization and to improve the total gain of the proposed patch antenna. The use of air as substrate leads to very high efficiency. The measured results show that the fabricated prototype achieves a −10 dB bandwidth of 44.9% (1.6–2.7 GHz), a small reflection coefficient of −24.4 dB and a high efficiency, i.e., 85% at 2.45 GHz. The radiation performance of the proposed antenna is measured, showing a peak realized gain of 8.5 dBi with cross polarization level less than −20 dB at 2.45 GHz and a 3 dB gain bandwidth of 61.22%.This thesis also presents two slot antenna designs: a dual band slot antenna with F-shaped slits for C-band and X-band applications, and a high gain slot antenna with reflector for 2U CubeSat. In the first antenna design, the symmetrical F-shaped slits were embedded to generate an extra resonant frequency and hence improve the antenna bandwidth. The proposed antenna achieved an impedance bandwidth of 500 MHz and a total gain of 5.9 at 5.1 GHz. For the second slot antenna designs, a metallic part of 2U CubeSat’s surface was used as a reflector below the proposed antenna to redirect the back radiation forward. This leads to a substantial suppression of back lobe radiation and hence significant increase of the antenna total gain. The proposed antenna achieved a superior measured gain of 9.1 dBi at 2.7 GHz, reflection coefficient of -21 dB, and an impedance bandwidth of 310 MHz (2.63-2.94 GHz).Finally, this thesis presents the design and measurement of a compact wide-band Circularly Polarized (CP) monopole antenna for CubeSat applications operating in the X-band.To achieve miniaturization and enhance the radiation performance, the proposed antenna is backed with an Artificial Magnetic Conductor (AMC) Metasurface. It provides a wide -10-dB Impedance Bandwidth (IBW) of 55.12% (6.57–10.98 GHz), and a 3dB Axial Ratio Bandwidth (ARBW) of 23.25% (7.62–9.48 GHz) with a compact size of 0.5λ0×0.5λ0×0.1λ0 at the operating frequency of 8 GHz.</p
Numerical simulation of a single shear scenario in fibreglass rock bolts
No full textThis study describes developing and validating a numerical model for a single shear test on 20-tonne fibreglass rock bolts using FLAC3D. For this, some pure single-shearing tests were conducted using a metal guillotine single-shearing apparatus. Following this, a conceptual model, including two rectangular blocks with a width and depth of 100 mm and a height of 200 mm, was created to assess the performance of a single-shear fibreglass rock bolt. The conceptual model was then uploaded to FLAC3D. The numerical model incorporates critical parameters such as block dimensions, grid numbers and node spacing to ensure simulation accuracy. The FLAC3D model closely matched the experimental test results in predicting the bolt's properties, including the elastic transition trough, peak shear force, peak displacement and post-failure response. However, the model failed to predict shear forces at lower displacements. This discrepancy may be due to assuming a near-perfect scenario with minimal system imperfections, leading to higher shear forces at lower displacements due to the absence of imperfections to dampen the shear force transfer. As expected, with the increase in shear forces, the model aligned well with data from the experimental tests.</p
Sustainability in underground mining and geotechnical practices
No full textThis research investigates the incorporation of recycled waste materials, specifically tyre rubber powder (TRP) into cementitious grouts used in underground mining. By evaluating the impact of waste materials on the grout's mechanical properties, microstructure, and flow behaviour, this research investigates the feasibility of enhancing the sustainability of mining operations. While the inclusion of waste materials generally leads to a slight decrease in the grout's strength, it also improves its flow characteristics, enabling a reduction in water content. This research aligns with the growing emphasis on sustainability within the mining industry, demonstrating a pathway towards more environmentally responsible practices by minimising waste, reducing reliance on virgin materials, and enhancing the long-term environmental stability of mining operations. This research provides valuable insights for the mining industry, highlighting the potential of utilising recycled materials to improve the environmental performance of underground mining projects without compromising operational efficiency.</p
Methane gas detectors accuracy and response times under varying gas flow and sensor occlusion conditions
No full textAccurate and timely detection of methane gas levels in underground coal mines is crucial in the prevention of gas explosions. Yet, the nature of the mine environment with its high humidity and dust can cause the gas detectors to become occluded with a buildup of dust over time. These occlusions have the potential to compromise the accuracy and/or response time of gas readings in real time.The accuracy and response times of fixed gas detectors are validated in typical mining operations with known gas mixtures and gas flow rates during commissioning, and at regular maintenance intervals. Original Equipment Manufacturer (OEM) calibration cups are used to allow the calibration gas to flow into the detector while minimising environmental disturbances.Simtars has undertaken a comprehensive series of tests to evaluate the effects of occlusion on the accuracy and response times of real time methane detectors. Tests were conducted using both OEM calibration cups and purpose-built Simtars test calibration cups. The influence of various levels of occlusion on the gas detector accuracy and response time was assessed.This paper presents the outcomes of this study, comparing the accuracy and response times of seven methane gas detectors currently in use in Australian mines. Simulated occlusions were carried out with occlusion percentages of 65 %, 80 %, 90 % and 95 % using three methane concentrations of 0.5 %, 1.5 % and 2.5 % for each occlusion percentage.The results demonstrated significant variability under varying test conditions. Recommendations to improve gas detector validation, calibration, and performance assessment based on the test outcomes are presented.</p