48080 research outputs found
Sort by
Re-Thinking Table Tennis as a Team Sport
No full textA new horizon for Table Tennis is presented, with its traditional singles and doubles configurations extended to a real Team Game, with three-player teams facing each other on a round (or quasi-round) table: TRIPLES. This overcomes the limitations in present competitive table tennis TEAM events (Olympics, World Championships), which mostly have 3-player teams who never play each other as teams. The rationale, development history, equipment design and construction, as well as rules for Triples are described, as are other new table tennis game variations spawned by the round table shape. Various photo- and video examples of games in action are included, and a successful 10-year application/competition case study, with up to 8 Triples teams of various standards, is described. It is concluded that Triples is a practically acceptable new version of table tennis, ready for introduction into the serious/international game repertoire. Some suggestions on possible next steps complete the presentation.</p
Australian subtropical vegetation and wetland response to fire, climate and nutrient availability during the Holocene
No full textThe iconic sand dune systems of Minjerribah (North Stradbroke Island), in southeastern Queensland, Australia, host numerous lakes and swamps containing organic-rich sediment deposits that record changes in climate, fire and surrounding vegetation. Palaeoenvironmental reconstructions from individual locations can provide insights into changes in the environment, but determining the regional extent of these changes is seldom possible from a single site. Multi-site compilations help elucidate the geographical nature of environmental changes and determine if they are driven by local or regional forces. Here, a synthesis of palynological records from six Minjerribah wetlands using a muti-tiered Monte Carlo empirical orthogonal function (EOF) analysis allows island-wide patterns of vegetation change to be identified. Coherent changes in vegetation were recorded, with first-order changes (EOF1) indicating a long-term shift in vegetation composition from closed forests towards woodland and heath vegetation. A compilation of macroscopic and microscopic charcoal from the same sites shares coherent patterns of change with a rainfall record from the island, suggesting that regional fire occurrence between 7000 and 2000 cal a bp was driven primarily by long-term variations in rainfall and its influence on biomass. Comparison with fire activity, rainfall, sedimentary carbon, nitrogen and dust records from Minjerribah suggests that regional vegetation changes occur primarily in response to long-term changes in nutrients and increasing rainfall variability. This analysis highlights the multi-millennial connection between vegetation composition, climate, nutrients and fire occurrence across the Holocene in subtropical environments.</p
"I am a British subject – deemed an alien": Marital Nationality and Australia’s Asian Communities
No full textIn the nineteenth and twentieth centuries, nations across the world instituted a system whereby women who married aliens lost their natural-born nationality. Studies on dependent marital nationality in Australia are emerging but there is still much to be uncovered. This thesis examines legal discussions, media articles, and a collection of women’s correspondence with government officials in attempts to have their nationality and accompanying rights restored. It asks why dependent nationality legislation remained law in Australia for so long despite widespread public and political opposition to it and seeks to uncover how dependent nationality affected Australian women married to aliens and their families, including women’s affective and emotional responses to their altered nationality status. As the largest non-white, non-Indigenous group in Australia, Chinese-Australian communities are of particular interest in this study as they negotiated the intersections of dependent nationality and racialised restrictions under the White Australia Policy. This thesis argues that the loss of nationality on marriage affected women in profoundly existential and emotional ways, as well as through tangible disabilities and disadvantages, and that these experiences could be more tragic for Australian women married to Chinese nationals.</p
Comprehensive Review of Wearable Antennas With Flexible Periodic Structures for Body-Effect Mitigation
No full textRecent advancements in wireless technology have prompted the development of wearable antennas, particularly for Wireless Body Area Networks (WBANs) used in sports, military activities, healthcare, and identification systems. Unlike traditional antennas, wearable antennas operate very close to the curved human body. Consequently, their performance metrics such as reflection coefficient, bandwidth, radiation characteristics, efficiency, gain, directivity, and Specific Absorption Rate (SAR) can be significantly affected by interactions with human body tissues. To address these challenges, periodic structures are integrated into wearable antenna designs to mitigate the effects of coupling and absorption by the human body. To date, a limited number of works have surveyed, compared, and categorized the proposed wearable antenna designs integrated with periodic structure based on their operating frequency bands and their interactions with the human body. To this end, this paper contributes to the literature by detailing the selection of materials, highlighting the limitations of wearable antennas, characterizing the periodic structures, elaborate on dielectric properties data of human body models, discussing the influence of periodic structures on antenna performance and their significance in isolating them from the human body. Furthermore, this study provides an in-depth review of 81 papers evaluating the performance of antennas integrated with periodic structures, both in free space and on the human body, across single-band, dual-band, and triple-band designs. The selected papers were chosen based on their publication in reputable journals, the quality of their research, and the comprehensiveness of their data analysis. In addition, it provides a summary of several common flexible materials used in wearable antennas with their electrical properties as well as the dielectric properties of the human body for different frequencies. Moreover, it discusses the challenges and considerations involved in designing appropriate wearable antennas.</p
Wear Resistance of Novel FeCr<sub>2</sub>VW<sub>0.3</sub> Refractory Medium Entropy Alloy
No full textHigh/Medium entropy materials are increasingly recognized for their potential in high-temperature applications. To enhance high temperature wear resistance, a novel medium entropy alloy, FeCr2VW0.3, was developed and synthesized using arc melting in an argon atmosphere. The resultant microstructure of the sintered composite exhibited a dual-phase composition of body-centered cubic (BCC) phases, with the BCC1 phase predominantly containing tungsten and the BCC2 phase enriched with vanadium. The BCC1 phase was the matrix and the BCC2 phase was distributed along the grain boundaries of the BCC1 phase. The BCC2 phase also had a much higher hardness than the BCC1 phase.This study investigated the dry sliding behavior of the medium entropy alloy, FeCr2VW0.3, against a silicon nitride ceramic ball under various loads (5N, 10N, 15N, 20N, and 50N) at room temperature for a duration of 20 minutes. The wear behavior of the alloy was further evaluated at room temperature, 450°C, 550°C and 650°C, under a constant load of 20N for 20 minutes. The findings demonstrate that the medium entropy alloy exhibits superior wear resistance against the silicon nitride ceramic, attributed mainly to the high hardness of the alloy. Notably, the wear rate decreased as the temperature increased.The primary wear mechanisms identified for FeCr2VW0.3 were adhesive wear at all tested temperatures, and oxidative wear at high temperatures. Plastic deformation induced grain refinement was also observed for the grains beneath the sliding track. The formation of multiple elements oxides and the presence of the hard BCC2 phase were crucial in minimizing the volume loss of FeCr2VW0.3 during high-temperature wear tests. The formation of metal oxides might have created a thin lubricious tribo-layer, which reduced the wear rate when testing at high temperature.</p
The application of emerging technologies to improve CMM pre-drainage and reduce emissions
No full textResearch is ongoing to quantify the effectiveness and benefits of emerging technologies to improve coal pre-drainage and reduce emissions for Metallurgical Coal (MC) mines. Firstly, this paper describes the application of Diagnostic Fracture Injection Test (DFIT) methods to identify Pressure-Dependant Permeability (PDP) behaviour and reservoir parameters and to acquire multi-well interference data in low-permeability environments. Next, this paper summarises the benefits of indirect hydraulic fracturing implantation in improving pre-drainage before gate road developments in a Bowen Basin underground mine. Further, using new commercially available micro-proppants with hydraulic fracturing or standalone treatments can improve drainage from coals exhibiting PDP behaviour. Finally, the potential benefits of reintroducing the former CRC Mining Tight-Radius Drilling (TRD) technology are proposed to improve CMM pre-drainage, reduce emissions, and enhance other non-coal mining applications.Next, previous research has quantified the economic benefits of implementing subterranean barriers in underground mining based on the former Australian Emissions Trading Scheme with parameters not significantly different from current conditions (i.e., the Safeguard Mechanisms). Subterranean barrier technologies with surface-to-inseam (SIS) well pre-drainage have recently been modelled to reduce emissions from open-cut mines by as much as 46% (0.45 Mt CO2-e) on a per km2 drainage area. Ongoing recommendations for further research in barrier implementation technology will also be discussed.The proposed technologies have either been field applied, laboratory tested under representative conditions in actual coal samples or modelled and peer-reviewed using representative Bowen Basin data. These technologies are applicable for pre-drainage or reducing emissions for all coal mine applications.</p
Stress and strain measurement for large physical models based on 3D-DIC
No full textPhysical modelling has long been used in the study of underground mining to, inter alia, understand strata movement, surface subsidence, and top coal caving. This paper explores the extended application of three-dimensional digital image correlation (3D-DIC) in the physical modelling of underground coal structures. By precise measurements of stress and strain around mining layouts subjected to varying loads, this study demonstrates the application of 3D-DIC to enhance the understanding of pillar and roadway behaviour under deep mining conditions. Measurements using LVDT and 3D-DIC were conducted during uniaxial compression tests on cylindrical synthetic samples to be able to compare the stress-strain relationships obtained by both methods. Large-scale benchmark tests of EPS (Expanded Polystyrene) foam were further performed to demonstrate the capability of 3D-DIC for localised stress and strain measurement of mining layouts within the physical models. The results demonstrate 3D-DIC as a reliable and precise technique for monitoring stress distribution within coal structures in complex geo-stress environments, providing deeper insights into the dynamic processes of pillar instability, rib bursts, roof movement, and floor heave.</p
Multisectoral aspirations for food systems governance and the enduring dominance of agriculture
No full textTransforming food systems to be healthier, more sustainable and more equitable will require coordinated efforts across diverse sectors. The agricultural sector typically dominates food system governance, potentially risking imbalance in the food systems space and sustaining an emphasis on food availability and agricultural production over more integrated solutions to food system challenges. We examine contemporary food systems governance, with a focus on the UN Food Systems Summit (UNFSS) and on the Pacific and East and Southeast Asian regions. We reflect on the implications of agricultural dominance in the food system space and identify opportunities to support multisectoral food system governance to facilitate positive food system change.</p
Metro moss: integrating ecology and physiology to understand how urbanisation impacts species diversity, microclimate and stress response
No full textThe abstract for this item has not been populated.</p
Voting under Social Network Environments: A Comprehensive Study of Strategic Voting and Campaigning via Social Influence
No full textIn an era marked by the omnipresence of online social networks, this thesis explores the effects of social network environments on voting. Voting aggregates community preferences into collective decisions. Social networks determine how information flows and how influence diffuses within a community, potentially swaying individual preferences and voting outcomes. It is challenging to obtain a thorough comprehension of the dynamic effects of social network environments on voting due to three challenging issues: (1) strategic voting (not reporting sincere preferences), (2) complex social network structures, and (3) social influence.</p