977 resultados para field line


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This thesis develops and applies an analytical method to treat the blast response of glass façades and studies the influence of controlling parameters such as all component materials and geometric properties, support conditions and energy absorption, and hence establishes a framework for their design for a credible blast event.

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The work of French sociologist, anthropologist and philosopher Pierre Bourdieu has been influential across a set of cognate disciplines that can be classified as physical culture studies. Concepts such as field, capital, habitus and symbolic violence have been used as theoretical tools by scholars and students looking to understand the nature and purpose of sport, leisure, physical education and human movement within wider society. Pierre Bourdieu and Physical Culture is the first book to focus on the significance of Bourdieu’s work for, and in, physical culture. Bringing together the work of leading and emerging international researchers, it introduces the core concepts in Bourdieu’s thought and work, and presents a series of fascinating demonstrations of the application of his theory to physical culture studies. A concluding section discusses the inherent difficulties of choosing and using theory to understand the world around us. By providing an in-depth and multi-layered example of how theory can be used across the many and varied components of sport, leisure, physical education and human movement, this book should help all serious students and researchers in physical culture to better understand the importance of social theory in their work.

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In this paper, a stress and coping perspective is used to outline the processes that determine employee adaptation to organisational change. A theoretical framework that simultaneously considers the effects of event characteristics, situational appraisals, coping strategies, and coping resources is reviewed. Three empirical investigations of organisational change that have tested various components of the model are then presented. In the first study, there was evidence linking event characteristics, situational appraisals, coping strategies and coping resources to levels of employee adjustment in a sample of pilots employed in a newly merged airline company. In a more focused test of the model with a sample of employees experiencing a restructuring process in their organisation it was found that the provision of change-related information enhanced levels of efficacy to deal with the change process which, in turn, predicted psychological wellbeing, client engagement, and job satisfaction. In a study of managers affected by a new remuneration scheme, there was evidence to suggest that managers who received change-specific information and opportunities to participate in the change process reported higher levels of change readiness. Managers who reported higher levels of readiness for change also reported higher levels of psychological wellbeing and job satisfaction. These studies highlight ways in which managers and change agents can help employees to cope during times of organisational change.

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Increasing worldwide terrorist attacks involving explosives presents a growing need for a rapid and ranged explosive detection method that can safely be deployed in the field. Stand-off Raman spectroscopy shows great promise; however, the radiant exposures of lasers required for adequate signal generation are often much greater than what is safe for the eye or the skin, restricting use of the technique to un-populated areas. Here, by determining the safe exposure levels for lasers typically used in Raman spectroscopy, optimal parameter values are identified, which produce the largest possible detection range using power densities that do not exceed the eye-safe limit. It is shown that safe ultraviolet pulse energies can be more than three orders of magnitude greater than equivalent safe visible pulse energies. Coupling this to the 16-fold increase in Raman signal obtained in the ultraviolet at 266 nm over that at 532 nm results in a 131 times larger detection range for the eye-safe 266-nm system over an equivalent eye-safe 532-nm laser system. For the Raman system described here, this translates to a maximum range of 42 m for detecting Teflon with a 266-nm laser emitting a 100-mm diameter beam of 23.5-mJ nanosecond pulses.

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In October 2009, Professor David Nutt, eminent neuropsychopharmacologist and world leading expert on drugs, was dismissed as Chair of the UK government’s Advisory Council on the Misuse of Drugs for comments he made at the Centre for Crime and Justice Studies’ Eve Saville lecture. This article considers the role of evidence in political decision-making through the case of David Nutt. It is argued that the status of expert knowledge is in crisis for both the natural and the social sciences. We examine the role of the criminological advisor within emerging discourses of public criminology and suggest that high-stakes political issues can open up unprecedented opportunities for critical voices to engage in unbridled critique and to mobilise movements of dissent.

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The extreme diversity of conditions acting on railways necessitates a variety of experimental approaches to study the critical wear mechanisms that present themselves at the contact interface. This work investigates the effects of contact pressure and geometry in rolling-contact wear tests by using discs with different radii of curvature to simulate the varying contact conditions that may be typically found in the field. It is commonly adapted to line contact interface as it has constant contact pressure. But practical scenario of the rail wheel interface, the contact area increase and contact pressure change as tracks worn off. The tests were conducted without any significant amount of traction, but micro slip was still observed due to contact deformation. Moreover, variation of contact pressure was observed due to contact patch elongation and diameter reduction. Rolling contact fatigue, adhesive and sliding wear were observed on the curved contact interface. The development of different wear regimes and material removal phenomena were analysed using microscopic images in order to broaden the understanding of the wear mechanisms occurring in the rail-wheel contact.

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In this work we discuss the development of a mathematical model to predict the shift in gas composition observed over time from a producing CSG (coal seam gas) well, and investigate the effect that physical properties of the coal seam have on gas production. A detailed (local) one-dimensional, two-scale mathematical model of a coal seam has been developed. The model describes the competitive adsorption and desorption of three gas species (CH4, CO2 and N2) within a microscopic, porous coal matrix structure. The (diffusive) flux of these gases between the coal matrices (microscale) and a cleat network (macroscale) is accounted for in the model. The cleat network is modelled as a one-dimensional, volume averaged, porous domain that extends radially from a central well. Diffusive and advective transport of the gases occurs within the cleat network, which also contains liquid water that can be advectively transported. The water and gas phases are assumed to be immiscible. The driving force for the advection in the gas and liquid phases is taken to be a pressure gradient with capillarity also accounted for. In addition, the relative permeabilities of the water and gas phases are considered as functions of the degree of water saturation.

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Background We hypothesised that alternating inhibitors of the vascular endothelial growth factor receptor (VEGFR) and mammalian target of rapamycin pathways would delay the development of resistance in advanced renal cell carcinoma (aRCC). Patients and methods A single-arm, two-stage, multicentre, phase 2 trial to determine the activity, feasibility, and safety of 12-week cycles of sunitinib 50 mg daily 4 weeks on / 2 weeks off, alternating with everolimus 10 mg daily for 5 weeks on / 1 week off, until disease progression or prohibitive toxicity in favourable or intermediate-risk aRCC. The primary end point was proportion alive and progression-free at 6 months (PFS6m). The secondary end points were feasibility, tumour response, overall survival (OS), and adverse events (AEs). The correlative objective was to assess biomarkers and correlate with clinical outcome. Results We recruited 55 eligible participants from September 2010 to August 2012. Demographics: mean age 61, 71% male, favourable risk 16%, intermediate risk 84%. Cycle 2 commenced within 14 weeks for 80% of participants; 64% received ≥22 weeks of alternating therapy; 78% received ≥22 weeks of any treatment. PFS6m was 29/55 (53%; 95% confidence interval [CI] 40% to 66%). Tumour response rate was 7/55 (13%; 95% CI 4% to 22%, all partial responses). After median follow-up of 20 months, 47 of 55 (86%) had progressed with a median progression-free survival of 8 months (95% CI 5–10), and 30 of 55 (55%) had died with a median OS of 17 months (95% CI 12–undefined). AEs were consistent with those expected for each single agent. No convincing prognostic biomarkers were identified. Conclusions The EVERSUN regimen was feasible and safe, but its activity did not meet pre-specified values to warrant further research. This supports the current approach of continuing anti-VEGF therapy until progression or prohibitive toxicity before changing treatment.

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Light emitting field effect transistors (LEFETs) are emerging as a multi-functional class of optoelectronic devices. LEFETs can simultaneously execute light emission and the standard logic functions of a transistor in a single architecture. However, current LEFET architectures deliver either high brightness or high efficiency but not both concurrently, thus limiting their use in technological applications. Here we show an LEFET device strategy that simultaneously improves brightness and efficiency. The key step change in LEFET performance arises from the bottom gate top-contact device architecture in which the source/drain electrodes are semitransparent and the active channel contains a bi-layer comprising of a high mobility charge-transporting polymer, and a yellow-green emissive polymer. A record external quantum efficiency (EQE) of 2.1% at 1000cd/m2 is demonstrated for polymer based bilayer LEFETs.

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This article provides an overview of battery, with a particular focus on the role that consent plays in contact sports. The limits of implied consent in sport will also be discussed, followed by a brief overview of other relevant defences. Finally, issues of damages and vicarious liability will be addressed.

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A candidate gene approach using type I single nucleotide polymorphism (SNP) markers can provide an effective method for detecting genes and gene regions that underlie phenotypic variation in adaptively significant traits. In the absence of available genomic data resources, transcriptomes were recently generated in Macrobrachium rosenbergii to identify candidate genes and markers potentially associated with growth. The characterisation of 47 candidate loci by ABI re-sequencing of four cultured and eight wild samples revealed 342 putative SNPs. Among these, 28 SNPs were selected in 23 growth-related candidate genes to genotype in 200 animals selected for improved growth performance in an experimental GFP culture line in Vietnam. The associations between SNP markers and individual growth performance were then examined. For additive and dominant effects, a total of three exonic SNPs in glycogen phosphorylase (additive), heat shock protein 90 (additive and dominant) and peroxidasin (additive), and a total of six intronic SNPs in ankyrin repeats-like protein (additive and dominant), rolling pebbles (dominant), transforming growth factor-β induced precursor (dominant), and UTP-glucose-1-phosphate uridylyltransferase 2 (dominant) genes showed significant associations with the estimated breeding values in the experimental animals (P =0.001−0.031). Individually, they explained 2.6−4.8 % of the genetic variance (R2=0.026−0.048). This is the first large set of SNP markers reported for M. rosenbergii and will be useful for confirmation of associations in other samples or culture lines as well as having applications in marker-assisted selection in future breeding programs.

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BACKGROUND For engineering graduates to be work-ready with marketable skills they must not only be well-versed with engineering science and its applications, but also able to adapt to using commercial software that is widely used in engineering practice. Hydrological/hydraulic modelling is one aspect of engineering practice which demands the ability to apply fundamentals into design and construction using software. The user manuals for such software are usually tailored for the experienced engineer but not for undergraduates who typically are novices to concepts of modelling and software tools. As the focus of a course such as Advanced Water Engineering is on the wider aspects of engineering application of hydrological and hydraulic concepts, it is ineffective for the lecturers to direct the students to user manuals as students have neither the time nor the desire to sift through numerous pages in a manual. An alternative and efficient way to demonstrate the use of the software is enabling students to develop a model to simulate real-world scenario using the tools of the software and directing them to make informed decisions based on outcomes. PURPOSE Past experience of the lecturer showed that the resources available for the students left a knowledge gap leading to numerous student queries outside contact hours. The purpose of this study is to assess how effective purpose-built video resources can be in supplementing the traditional learning resources to enhance student learning. APPROACH Short-length animated video clips comprising guided step-by-step instructions were prepared using screen capture software to capture screen activity and later edited to focus on specific features using pop-up annotations; Vocal narration was purposely excluded to avoid disturbances due to noise and allow different learning paces of individual students. The video clips were made available to the students alongside the traditional resources/approaches such as in-class demonstrations, guideline notes, and tips for efficient and error-free procedural descriptions. The number of queries the lecturer received from the student cohort outside the lecture times was recorded. An anonymous survey to assess the usefulness and adequacy of the courseware was conducted. OUTCOMES While a significant decline in the number of student queries was noted, an overwhelming majority of the survey respondents confirmed the usefulness of the purpose-developed courseware. CONCLUSIONS/RECOMMENDATIONS/SUMMARY The survey and lecturer’s experience indicated that animated demonstration video clips illustrating the various steps involved in developing hydrologic and hydraulic models and simulating design scenarios is an effective supplement for traditional learning resources. Among the many advantages of the custom-made video clips as a learning resource are that they (1) highlight the aspects that are important to undergraduate learning but not available in the software manuals as the latter are designed for more mature users/learners; (2) provide short, to-the point communication in a step-by-step manner; (3) allow students flexibility to self-learn at their own pace; (4) enhance student learning; and (5) enable time savings for the lecturer in the long term by avoiding queries of a repetitive nature. It is expected that these newly developed resources will be improved to incorporate students’ suggestions before being offered to future cohorts of students. The concept can also be expanded to other relevant courses where animated demonstrations of key modelling steps are beneficial to student learning.

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In absolute terms, there have been improvements in social resources for all racial and ethnic groups in the United States. The rise in education levels among blacks and Hispanics, for instance, suggests a lessening of the gap between classes, beginning in the later part of the 1960’s (Kao & Thompson, 2003). Yet the divide in income and to a lesser extent education between peoples who differ in gender, skin color and ethnic origin continues and in many ways is greater now than ever (Danziger & Gottschalk, 1997); (Gottschalk, 1997). The psychological distance between those high and those low in social-economic status continues unabated and threatens to undermine the capacity of communities to foster the positive architecture of hope, optimism and equal opportunity that holds us together as a nation...

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It is difficult to determine sulfur-containing volatile organic compounds in the atmosphere because of their reactivity. Primary off-line techniques may suffer losses of analytes during the transportation from field to laboratory and sample preparation. In this study, a novel method was developed to directly measure dimethyl sulfide at parts-per-billion concentration levels in the atmosphere using vacuum ultraviolet single photon ionization time-of-flight mass spectrometry. This technique offers continuous sampling at a response rate of one measurement per second, or cumulative measurements over longer time periods. Laboratory prepared samples of different concentrations of dimethyl sulfide in pure nitrogen gas were analyzed at several sampling frequencies. Good precision was achieved using sampling periods of at least 60 seconds with a relative standard deviation of less than 25%. The detection limit for dimethyl sulfide was below the 3 ppb olfactory threshold. These results demonstrate that single photon ionization time-of-flight mass spectrometry is a valuable tool for rapid, real-time measurements of sulfur-containing organic compounds in the air.

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BACKGROUND Many koala populations around Australia are in serious decline, with a substantial component of this decline in some Southeast Queensland populations attributed to the impact of Chlamydia. A Chlamydia vaccine for koalas is in development and has shown promise in early trials. This study contributes to implementation preparedness by simulating vaccination strategies designed to reverse population decline and by identifying which age and sex category it would be most effective to target. METHODS We used field data to inform the development and parameterisation of an individual-based stochastic simulation model of a koala population endemic with Chlamydia. The model took into account transmission, morbidity and mortality caused by Chlamydia infections. We calibrated the model to characteristics of typical Southeast Queensland koala populations. As there is uncertainty about the effectiveness of the vaccine in real-world settings, a variety of potential vaccine efficacies, half-lives and dosing schedules were simulated. RESULTS Assuming other threats remain constant, it is expected that current population declines could be reversed in around 5-6 years if female koalas aged 1-2 years are targeted, average vaccine protective efficacy is 75%, and vaccine coverage is around 10% per year. At lower vaccine efficacies the immunological effects of boosting become important: at 45% vaccine efficacy population decline is predicted to reverse in 6 years under optimistic boosting assumptions but in 9 years under pessimistic boosting assumptions. Terminating a successful vaccination programme at 5 years would lead to a rise in Chlamydia prevalence towards pre-vaccination levels. CONCLUSION For a range of vaccine efficacy levels it is projected that population decline due to endemic Chlamydia can be reversed under realistic dosing schedules, potentially in just 5 years. However, a vaccination programme might need to continue indefinitely in order to maintain Chlamydia prevalence at a sufficiently low level for population growth to continue.