390 resultados para heat capacity laser
Resumo:
We investigated the influence of different gas environments on the fabrication of surfaces, homogeneously covered with equally sized and spaced micro-structures. Two types of structures have been successfully micro-machined with a femtosecond laser on titanium surfaces in various atmospheres. The surface chemistry of samples machined in oxygen and helium shows TiO2, while machining in nitrogen leads to an additional share of TiN. The actual surface structure was found to vary significantly as a function of the gas environment. We found that the ablated particles and their surface triggered two consecutive events: The optical properties of the gas environment became non-isotropic which then led to the pulse intensity being redistributed throughout the cross section of the laser beam. Additionally, the effective intensity was further reduced for TiN surfaces due to TiN's high reflectivity. Thus, the settings for the applied raster-scanning machining method had to be adjusted for each gas environment to produce comparable structures. In contrast to previous studies, where only noble gases were found suitable to produce homogeneous patches, we obtained them in an oxygen environment.
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Access to energy is a fundamental component of poverty abatement. People who live in homes without electricity are often dependent on dirty, time-consuming and disproportionately expensive solid fuel sources for heating and cooking. [1] In developing countries, the Human Development Index (HDI), which comprises measures of standard of living, longevity and educational attainment, increases rapidly with per capita electricity use. [2] For these reasons the United Nations has been making a concerted effort to promote global access to energy, first by naming 2012 the Year of Sustainable Energy for All, [3] and now by declaring 2014-2024 the Decade of Sustainable Energy for All. [4]
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Analytical techniques for measuring and planning railway capacity expansion activities have been considered in this article. A preliminary mathematical framework involving track duplication and section sub divisions is proposed for this task. In railways these features have a great effect on network performance and for this reason they have been considered. Additional motivations have also arisen from the limitations of prior models that have not included them.
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This article focusses upon multi-modal transportation systems (MMTS) and the issues surrounding the determination of system capacity. For that purpose a multi-objective framework is advocated that integrates all the different modes and many different competing capacity objectives. This framework is analytical in nature and facilitates a variety of capacity querying and capacity expansion planning.
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Background The Circle of Willis (CoW) is the most important collateral pathway of the cerebral artery. The present study aims to investigate the collateral capacity of CoW with anatomical variation when unilateral internalcarotid artery (ICA) is occluded. Methods Basing on MRI data, we have reconstructed eight 3D models with variations in the posterior circulation of the CoW and set four different degrees of stenosis in the right ICA, namely 24%, 43%, 64% and 79%, respectively. Finally, a total of 40 models are performed with computational fluid dynamics simulations. All of the simulations share the same boundary condition with static pressure and the volume flow rate (VFR) are obtained to evaluate their collateral capacity. Results As for the middle cerebral artery (MCA) and the anterior cerebral artery (ACA), the transitional-type model possesses the best collateral capacity. But for the posterior cerebral artery (PCA), unilateral stenosis of ICA has the weakest influence on the unilateral posterior communicating artery (PCoA) absent model. We also find that the full fetal-type posterior circle of Willis is an utmost dangerous variation which must be paid more attention. Conclusion The results demonstrate that different models have different collateral capacities in coping stenosis of unilateral ICA and these differences can be reflected by different outlets. The study could be used as a reference for neurosurgeon in choosing the best treatment strategy.
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Following the Association of Southeast Asian Nations (ASEAN) senior transport officials meeting in May 2011, the Secretariat requested the Asian Development Bank (ADB) to provide assistance to improve road safety in ASEAN. In response, ADB, funded by the Japan Fund for Poverty Reduction, has begun an innovative approach to capacity building that has already been adapted and replicated in other sub-regions. This paper will discuss the model central to the project. The Road Safety Capacity Building for ASEAN Project commenced in May 2013. Each country has appointed a National Focal Point (NFP) to identify and coordinate information. A team of International Experts were appointed to develop materials and present a comprehensive train the trainer program focused on five key areas. Thirty eight senior Government officers from across ASEAN attended a two week program at ADB headquarters in Manila and will arrange and deliver specific training and associated activities to other colleagues within their country. ADB has appointed a National Consultant to work in partnership with the trainees on a range of activities including development of “pipeline project proposals” for funding consideration investors and donors. As part of the project, a draft ASEAN Regional Road Safety Strategy document has been prepared and consultation will further refine its directions and contents. The project will reach its conclusion in 2015 and a follow up phase three project is being considered.
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Road crashes and injuries have become a growing issue worldwide. In 2011, more than 75,000 people died in road crashes in the ten member countries of the Association of South East Asian Nations (ASEAN) and many times this number sustained long term injuries. In 2014, the Asian Development Bank (ADB), funded by the Japan Fund for Poverty Reduction, commenced a package of actions to improve road safety in ASEAN. In 2015, as part of the technical assistance for this project, a Road Safety Advisor was appointed for Cambodia for four months. The assignment produced several primary outputs, which included the organization of national training on traffic law enforcement and road safety management, the conduct of a training needs survey and cost analysis study, and the development of a proposal for strengthening speed management. It is important to note that unlike other ADB technical assistance projects, this assignment adopted a capacity building approach, which promoted and encouraged the local road safety team in the government to step up and take action. The research capacity building approach adopted in this project highlighted the feasibility of increasing participation from existing stakeholders, especially the government in identifying existing human resources, building the capacity of relevant government officials and supporting them to take the ownership of the project. It is hoped that similar outcomes will occur in the other ASEAN countries.
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Australia is the world’s third largest exporter of raw sugar after Brazil and Thailand, with around $2.0 billion in export earnings. Transport systems play a vital role in the raw sugar production process by transporting the sugarcane crop between farms and mills. In 2013, 87 per cent of sugarcane was transported to mills by cane railway. The total cost of sugarcane transport operations is very high. Over 35% of the total cost of sugarcane production in Australia is incurred in cane transport. A cane railway network mainly involves single track sections and multiple track sections used as passing loops or sidings. The cane railway system performs two main tasks: delivering empty bins from the mill to the sidings for filling by harvesters; and collecting the full bins of cane from the sidings and transporting them to the mill. A typical locomotive run involves an empty train (locomotive and empty bins) departing from the mill, traversing some track sections and delivering bins at specified sidings. The locomotive then, returns to the mill, traversing the same track sections in reverse order, collecting full bins along the way. In practice, a single track section can be occupied by only one train at a time, while more than one train can use a passing loop (parallel sections) at a time. The sugarcane transport system is a complex system that includes a large number of variables and elements. These elements work together to achieve the main system objectives of satisfying both mill and harvester requirements and improving the efficiency of the system in terms of low overall costs. These costs include delay, congestion, operating and maintenance costs. An effective cane rail scheduler will assist the traffic officers at the mill to keep a continuous supply of empty bins to harvesters and full bins to the mill with a minimum cost. This paper addresses the cane rail scheduling problem under rail siding capacity constraints where limited and unlimited siding capacities were investigated with different numbers of trains and different train speeds. The total operating time as a function of the number of trains, train shifts and a limited number of cane bins have been calculated for the different siding capacity constraints. A mathematical programming approach has been used to develop a new scheduler for the cane rail transport system under limited and unlimited constraints. The new scheduler aims to reduce the total costs associated with the cane rail transport system that are a function of the number of bins and total operating costs. The proposed metaheuristic techniques have been used to find near optimal solutions of the cane rail scheduling problem and provide different possible solutions to avoid being stuck in local optima. A numerical investigation and sensitivity analysis study is presented to demonstrate that high quality solutions for large scale cane rail scheduling problems are obtainable in a reasonable time. Keywords: Cane railway, mathematical programming, capacity, metaheuristics
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The creative work comprises six short digital screen stories and emerges from a collaboration between the Discipline of Film Screen and Animation at Queensland University of Technology and the Centre for Social and Creative Media at University of Goroka, funded via the Department of Foreign Affairs and Trade's Australia Awards Fellowship. Six fellows traveled from Papua New Guinea to Brisbane for a two-week intensive course to learn the advanced skills necessary in order to create media that will empower women and girls to make more of their own economies in Papua New Guinea, and increase the representation of women and their well-being through leadership and decision-making. The resulting creative work is evidence of innovative media teaching-making methods designed to build human and cultural assets in PNG and address the increasing demand for media materials driven by the influx of mobile phones and internet services. The creative work provides a platform to directly address and positively impact gender issues in PNG and builds on the success of the Pawa Meri project, which trained six female directors to tell stories of women in leadership roles in PNG. One of the directors was a producer of this creative work. The creative work frames but problematises the complex issues influencing gender equity through the selection of content and narrative structures in ways which address the dynamics of male/female relationships and power in PNG society and will include strategies to illustrate transformed male and female behaviours. The creative work adopts a scaffolded approach, incorporating the findings of the Train the Trainer approach developed by UoG and QUT for the Life Drama research project. The creative work takes into account current developmental themes and approaches in the production of rich media products, and skills the key participants so that they are able to in turn train others in the wider community. The creative work was presented to partners and key stakeholders on 3 July 2015 at the Glasshouse, QUT Creative Industries Precinct and at the Dean’s Research Seminar Poster Exhibition 15 July 2015 at Room 212-213, Level 2, J Block, Gardens Point QUT and subsequent eBook. It has since returned to PNG to be showcased and distributed, and the skills and strategies disseminated.
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Changing the topology of a railway network can greatly affect its capacity. Railway networks however can be altered in a multitude of different ways. As each way has significant immediate and long term financial ramifications, it is a difficult task to decide how and where to expand the network. In response some railway capacity expansion models (RCEM) have been developed to help capacity planning activities, and to remove physical bottlenecks in the current railway system. The exact purpose of these models is to decide given a fixed budget, where track duplications and track sub divisions should be made, in order to increase theoretical capacity most. These models are high level and strategic, and this is why increases to the theoretical capacity is concentrated upon. The optimization models have been applied to a case study to demonstrate their application and their worth. The case study evidently shows how automated approaches of this nature could be a formidable alternative to current manual planning techniques and simulation. If the exact effect of track duplications and sub-divisions can be sufficiently approximated, this approach will be very applicable.
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Steel roofs made of thin cold-formed steel roof claddings and battens are widely used in low-rise residential and industrial buildings all around the world. However, they suffer from premature localised pull-through failures in the batten to rafter connections during high wind events. A recent study proposed a suitable design equation for the pull-through failures of thin steel roof battens. However, it was limited to static wind uplift loading. In contrast, most cyclone/storm events produce cyclic wind uplift forces on roofs for a significantly long period, thus causing premature fatigue pull-through failures at lower loads. Therefore, a series of constant amplitude cyclic load tests was conducted on small and full scale roof panels made of a commonly used industrial roof batten to develop their S-N curves. A series of multi-level cyclic tests, including the recently introduced low-high-low (LHL) fatigue loading test, was also undertaken to simulate a design cyclone. Using the S-N curves, the static pull-through design capacity equation was modified to include the effects of fatigue. Applicability of Miner’s rule was evaluated in order to predict the fatigue damage caused by multi-level cyclic tests such as the LHL test, and suitable modifications were made. The combined use of the modified Miner’s law and the S-N curve of roof battens will allow a conservative estimation of the fatigue design capacity of roof battens without conducting the LHL tests simulating a design cyclone. This paper presents the details of this study, and the results.
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This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the effects of heat acclimation interventions aimed at protecting health and performance from exertional heat stress.
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This paper develops theory that quantifies transit route passenger-relative load factor and distinguishes it from occupancy load factor. The ratio between these measures is defined as the load diversity coefficient, which as a single measure characterizes the diversity of passenger load factor between route segments according to the origin-destination profile. The relationship between load diversity coefficient and route coefficient of variation in occupancy load factor is quantified. Two tables are provided that enhance passenger capacity and quality of service (QoS) assessment regarding onboard passenger load. The first expresses the transit operator’s perspective of load diversity and the passengers’ perspective of load factor relative to the operator’s, across six service levels corresponding to ranges of coefficient of variation in occupancy load factor. The second interprets the relationships between passenger average travel time and each of passenger-relative load factor and occupancy load factor. The application of this methodology is illustrated using a case study of a premium radial bus route in Brisbane, Australia. The methodology can assist in benchmarking and decision making regarding route and schedule design. Future research will apply value of time to QoS measurement, reflecting perceived passenger comfort through crowding and average time spent aboard. This would also assist in transit service quality econometric modeling.
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This poster introduces Passenger Relative Load Factor for a route or individual bus service as a capacity and quality of service measure, distinguishing it from Occupancy Load Factor. It introduces Load Diversity Coefficient as the ratio of Passenger Relative Load Factor to Occupancy Load Factor, and relates Load Diversity Coefficient to Coefficient of Variation in Occupancy Load Factor. It qualifies the operator’s and passengers’ perspectives of load factor based on Coefficient of Variation in Occupancy Load Factor along a route. A case study using weekday Automatic Fare Collection (AFC) data on a premium bus line in Brisbane, Australia illustrates the methodology. The compendium paper also qualifies the operator’s and passengers’ perspectives of these load factors along with Passengers’ Average Travel Time for capacity and quality of service assessment.
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The demand for cancer care is growing due to the increasing incidence of cancer and the improved effectiveness of cancer treatments. It is important that cancer nurses continue to improve patient outcomes through research and the use of evidence in practice development, education and policy. This paper describes a case report of a collaborative academic healthcare model that creates capacity for cancer nursing research and evidence-based practice. The Cancer Nursing Professorial Precinct is a strategic collaboration between the Royal Brisbane and Women’s Hospital (RBWH) and Queensland University of Technology (QUT), in Brisbane Australia. The outcomes of this initiative has been remarkable. The principles and strategies used in this initiative may be useful for cancer services in other countries.