999 resultados para light rail


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This paper discusses major obstacles for the adoption of low cost level crossing warning devices (LCLCWDs) in Australia and reviews those trialed in Australia and internationally. The argument for the use of LCLCWDs is that for a given investment, more passive level crossings can be treated, therefore increasing safety benefits across the rail network. This approach, in theory, reduces risk across the network by utilizing a combination of low-cost and conventional level crossing interventions, similar to what is done in the road environment. This paper concludes that in order to determine if this approach can produce better safety outcomes than the current approach, involving the incremental upgrade of level crossings with conventional interventions, it is necessary to perform rigorous risk assessments and cost-benefit analyses of LCLCWDs. Further research is also needed to determine how best to differentiate less reliable LCCLWDs from conventional warning devices through the use of different warning signs and signals. This paper presents a strategy for progressing research and development of LCLCWDs and details how the Cooperative Research Centre (CRC) for Rail Innovation is fulfilling this strategy through the current and future affordable level crossing projects.

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This paper presents a study on estimating the latent demand for rail transit in Australian context. Based on travel mode-choice modelling, a two-stage analysis approach is proposed, namely market population identification and mode share estimation. A case study is conducted on Midland-Fremantle rail transit corridor in Perth, Western Australia. The required data mainly include journey-to-work trip data from Australian Bureau of Statistics Census 2006 and work-purpose mode-choice model in Perth Strategic Transport Evaluation Model. The market profile is analysed, such as catchment areas, market population, mode shares, mode specific trip distributions and average trip distances. A numerical simulation is performed to test the sensitivity of the transit ridership to the change of fuel price. A corridor-level transit demand function of fuel price is thus obtained and its characteristics of elasticity are discussed. This study explores a viable approach to developing a decision-support tool for the assessment of short-term impacts of policy and operational adjustments on corridor-level demand for rail transit.

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The State Library of Queensland is delighted to present Lumia: art/light/motion, a culmination of many years of collaboration by the Kuuki collective led by Priscilla Bracks and Gavin Sade. This extraordinary exhibition not only showcases the unique talent of these Queenslanders, it also opens up a world of future possibilities while re-presenting the past and present. These contemporary new media installations sit comfortably within the walls of the library as they are the distinctive products of inquisitive and philosophical minds. In a sense the exhibition highlights the longevity and purposefulness of a cultural learning institution, through the non-traditional use of data, information, research and collection interpretation. The exhibition simultaneously articulates one of our key objectives – to progress the state’s digital agenda. Two academic essays have been commissioned for this joint Kuuki and State Library of Queensland publication. The first is by artist and writer Paul Brown, who has specialised in art, science and technology since the late 1960s and in computational and generative art since the mid 1970s. Brown investigates the history of new media, which is celebrating its 60th anniversary, and clearly places Sade and Bracks at the forefront of this genre nationally. The second essay is by arts writer Linda Carroli, who has delved deeply into the thoughts and processes of the artists to bring to light the complex workings of the artists’ minds. The publication also features an interview Carroli conducted with the artists. This exhibition is playful, informative and contemplative. The audience is invited to play, and consequently to ponder the way we live and the environmental and social implications of our choices. The exhibition tempts us to travel deep into the Antarctic, plunge into the Great Barrier Reef, be swamped by an orchestra of crickets, enter the Charmed world and travel back in time to a Victorian parlour where you can interact with a ‘new-world’ lyrebird and consider a brave new world where our only link to the animal world is with robotic representations. In essence this exhibition is about ideas and knowledge and what better institution than the State Library of Queensland to partner such a project?. State Library is committed to preserving culture, exploring new media and creating new content as a lasting legacy of Queensland for all Queenslanders.

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A finite element numerical simulation is carried out to examine stress distributions on railhead in the vicinity of the endpost of a insulated rail joint. The contact patch and pressure distribution are considered using modified Hertzian formulation. A combined elasto-plastic material modelling available in Abaqus is employed in the simulation. A dynamic load factor of 1.21 is considered in modelling for the wheel load based on a previous study as part of this on going research. Shakedown theorem is employed in this study. A peak pressure load which is above the shakedown limit is determined as input load. As a result, a progressive damage in the railhead has been captured as depicted in the equivalent plastic strain plot.

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Fire safety design of building structures has received greater attention in recent times due to continuing loss of properties and lives during fires. However, fire performance of light gauge cold-formed steel structures is not well understood despite its increased usage in buildings. Cold-formed steel compression members are susceptible to various buckling modes such as local and distortional buckling and their ultimate strength behaviour is governed by these buckling modes. Therefore a research project based on experimental and numerical studies was undertaken to investigate the distortional buckling behaviour of light gauge cold-formed steel compression members under simulated fire conditions. Lipped channel sections with and without additional lips were selected with three thicknesses of 0.6, 0.8, and 0.95 mm and both low and high strength steels (G250 and G550 steels). More than 150 compression tests were undertaken first at ambient and elevated temperatures. Finite element models of the tested compression members were then developed by including the degradation of mechanical properties with increasing temperatures. Comparison of finite element analysis and experimental results showed that the developed finite element models were capable of simulating the distortional buckling and strength behaviour at ambient and elevated temperatures up to 800 °C. The validated model was used to determine the effects of mechanical properties, geometric imperfections and residual stresses on the distortional buckling behaviour and strength of cold-formed steel columns. This paper presents the details of the numerical study and the results. It demonstrated the importance of using accurate mechanical properties at elevated temperatures in order to obtain reliable strength characteristics of cold-formed steel columns under fire conditions.

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Insulated rail joints (IRJs) possess lower bending stiffness across the gap containing insulating endpost and hence are subjected to wheel impact. IRJs are either square cut or inclined cut to the longitudinal axis of the rails in a vertical plane. It is generally claimed that the inclined cut IRJs outperformed the square cut IRJs; however, there is a paucity of literature with regard to the relative structural merits of these two designs. This article presents comparative studies of the structural response of these two IRJs to the passage of wheels based on continuously acquired field data from joints strain-gauged closer to the source of impact. Strain signatures are presented in time, frequency, and avelet domains and the peak vertical and shear strains are systematically employed to examine the relative structural merits of the two IRJs subjected to similar real-life loading. It is shown that the inclined IRJs resist the wheel load with higher peak shear strains and lower peak vertical strains than that of the square IRJs.

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In Australia, young children who lack decision-making capacity can have regenerative tissue removed to treat another person suffering from a severe or life-threatening disease. While great good can potentially result from this as the recipient’s life may be saved, ethical unease remains over the ‘use’ of young children in this way. This paper examines the ethical approaches that have featured in the debate over the acceptability and limits of this practice, and how these are reflected in Australia’s legal regime governing removal of tissue from young children. This analysis demonstrates a troubling dichotomy within the Australia’s laws that requires decision-makers to adopt inconsistent ethical approaches depending on where a donor child is situated. It is argued that this inconsistency in approach warrants legal reform of this ethically sensitive issue.

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An experimental laboratory investigation was carried out to assess the structural adequacy of a disused PHO Class Flat Bottom Rail Wagon (FRW) for a single lane low volume road bridge application as per the design provisions of the Australian Bridge Design Standard AS 5100(2004). The investigation also encompassed a review into the risk associated with the pre-existing damage in wagons incurred during their service life on rail. The main objective of the laboratory testing of the FRW was to physically measure its performance under the same applied traffic loading it would be required to resist as a road bridge deck. In order to achieve this a full width (5.2m) single lane, single span (approximately 10m), simply supported bridge would be required to be constructed and tested in a structural laboratory. However, the available clear spacing between the columns of the loading portal frame encountered within the laboratory was insufficient to accommodate the 5.2m wide bridge deck excluding clearance normally considered necessary in structural testing. Therefore, only half of the full scale bridge deck (single FRW of width 2.6m) was able to be accommodated and tested; with the continuity of the bridge deck in the lateral direction applied as boundary constraints along the full length of the FRW at six selected locations. This represents a novel approach not yet reported in the literature for bridge deck testing to the best of the knowledge of the author. The test was carried out under two loadings provided in AS 5100 (2004) – one stationary W80 wheel load and the second a moving axle load M1600. As the bridge investigated in the study is a single lane single span low volume road bridge, the risk of pre-existing damage and the expected high cycle fatigue failure potential was assessed as being minimal and hence the bridge deck was not tested structurally for fatigue/ fracture. The high axle load requirements have instead been focussed upon the investigation into the serviceability and ultimate limit state requirements. The testing regime adopted however involved extensive recording of strains and deflections at several critical locations of the FRW. Three locations of W80 point load and two locations of the M1600 Axle load were considered for the serviceability testing; the FRW was also tested under the ultimate load dictated by the M1600. The outcomes of the experimental investigation have demonstrated that the FRW is structurally adequate to resist the prescribed traffic loadings outlaid in AS 5100 (2004). As the loading was directly applied on to the FRW, the laboratory testing is assessed as being significantly conservative. The FRW bridge deck in the field would only resist the load transferred by the running platform, where, depending on the design, composite action might exist – thereby the share of the loading which needs to be resisted by the FRW would be smaller than the system tested in the lab. On this basis, a demonstration bridge is under construction at the time of writing this thesis and future research will involve field testing in order to assess its performance.

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We report the production of free-standing thin sheets made up of mass-produced ZnO nanowires and the application of these nanowire sheets for the fabrication of ZnO/organic hybrid light-emitting diodes in the manner of assembly. Different p-type organic semiconductors are used to form heterojunctions with the ZnO nanowire film. Electroluminescence measurements of the devices show UV and visible emissions. Identical strong red emission is observed independent of the organic semiconductor materials used in this work. The visible emissions corresponding to the electron transition between defect levels within the energy bandgap of ZnO are discussed.