674 resultados para Critical incident technique
Resumo:
Insulated Rail Joints (IRJs) are safety critical component of the automatic block signalling and broken rail detection systems. IRJs exhibit several failure modes due to complex interaction between the railhead ends and the wheel tread near the gap. These localised zones could not be monitored using automatic sensing devices and hence are resorted to visual inspection only, which is error prone and expensive. In Australia alone currently there are 50,000 IRJs across 80,000 km of rail track. The significance of the problem around the world could thus be realised as there exists one IRJ for each 1.6 km track length. IRJs exhibit extremely low and variable service life; further the track substructure underneath IRJs degrade faster. Thus presence of the IRJs incur significant costs to track maintenance. IRJ failures have also contributed to some train derailments and various traffic disruptions in rail lines. This paper reports a systematic research carried out over seven years on the mechanical behaviour of IRJs for practically relevant outcomes. The research has scientifically established that stiffening the track bed for reduction in impact force is an ill-conceived concept and the most effective method is to reduce the gap size. Further it is established that hardening the railhead ends through laser coating (or other) cannot adequately address the metal flow problem in the long run; modification of the railhead profile is the only appropriate technique to completely eliminate the problem. Part of these outcomes has been adopted by the rail infrastructure owners in Australia.
Resumo:
Despite the extent of works done on modelling port water collisions, not much research effort has been devoted to modelling collisions at port anchorages. This paper aims to fill this important gap in literature by applying the Navigation Traffic Conflict Technique (NTCT) for measuring the collision potentials in anchorages and for examining the factors contributing to collisions. Grounding on the principles of the NTCT, a collision potential measurement model and a collision potential prediction model were developed. These models were illustrated by using vessel movement data of the anchorages in Singapore port waters. Results showed that the measured collision potentials are in close agreement with those perceived by harbour pilots. Higher collision potentials were found in anchorages attached to shoreline and international fairways, but not at those attached to confined water. Higher operating speeds, larger numbers of isolated danger marks and day conditions were associated with reduction in the collision potentials.
Resumo:
Modal flexibility is a widely accepted technique to detect structural damage using vibration characteristics. Its application to detect damage in long span large diameter cables such as those used in suspension bridge main cables has not received much attention. This paper uses the modal flexibility method incorporating two damage indices (DIs) based on lateral and vertical modes to localize damage in such cables. The competency of those DIs in damage detection is tested by the numerically obtained vibration characteristics of a suspended cable in both intact and damaged states. Three single damage cases and one multiple damage case are considered. The impact of random measurement noise in the modal data on the damage localization capability of these two DIs is next examined. Long span large diameter cables are characterized by the two critical cable parameters named bending stiffness and sag-extensibility. The influence of these parameters in the damage localization capability of the two DIs is evaluated by a parametric study with two single damage cases. Results confirm that the damage index based on lateral vibration modes has the ability to successfully detect and locate damage in suspended cables with 5% noise in modal data for a range of cable parameters. This simple approach therefore can be extended for timely damage detection in cables of suspension bridges and thereby enhance their service during their life spans.
Resumo:
Background Anaemia is common in critically ill patients, and has a significant negative impact on patients' recovery. Blood conservation strategies have been developed to reduce the incidence of iatrogenic anaemic caused by sampling for diagnostic testing. Objectives Describe practice and local guidelines in adult, paediatric and neonatal Australian intensive care units (ICUs) regarding blood sampling and conservation strategies. Methods Cross-sectional descriptive study, conducted July 2013 over one week in single adult, paediatric and neonatal ICUs in Brisbane. Data were collected on diagnostic blood samples obtained during the study period, including demographic and acuity data of patients. Institutional blood conservation practice and guidelines were compared against seven evidence-based recommendations. Results A total of 940 blood sampling episodes from 96 patients were examined across three sites. Arterial blood gas was the predominant reason for blood sampling in each unit, accounting for 82% of adult, 80% of paediatric and 47% of neonatal samples taken (p <. 0.001). Adult patients had significantly more median [IQR] samples per day in comparison to paediatrics and neonates (adults 5.0 [2.4]; paediatrics 2.3 [2.9]; neonatal 0.7 [2.7]), which significantly increased median [IQR] blood sampling costs per day (adults AUD$101.11 [54.71]; paediatrics AUD$41.55 [56.74]; neonatal AUD$8.13 [14.95]; p <. 0.001). The total volume of samples per day (median [IQR]) was also highest in adults (adults 22.3. mL [16.8]; paediatrics 5.0. mL [1.0]; neonates 0.16. mL [0.4]). There was little information about blood conservation strategies in the local clinical practice guidelines, with the adult and neonatal sites including none of the seven recommendations. Conclusions There was significant variation in blood sampling practice and conservation strategies between critical care settings. This has implications not only for anaemia but also infection control and healthcare costs.
Resumo:
As government and industry grapple with 21st century challenges, building the capacity to look at complex problems through fresh eyes is critical.
Resumo:
As conservatoire-style dance teaching has traditionally utilised a hierarchical approach through which the student must conform to the ideal requirements of the conventional technique, current discourse is beginning to question how dance training can develop technical acuity without stifling students' ability to engage creatively. In recent years, there has been growing interest in the field of somatics and its relationship to tertiary dance training due to the understanding that this approach supports creative autonomy by radically repositioning the student's relationship to embodied learning, skill acquisition, enquiry and performance. This research addresses an observable disjuncture between the skills of dancers graduating from tertiary training and Australian dance industry needs, which increasingly demand the co-creative input of the dancer in choreographic practice. Drawing from Action Research, this paper will discuss a project which introduces somatic learning approaches, primarily from Feldenkrais Method and Hanna Somatics, to first-year dance students in their transition into tertiary education. This paper acknowledges previous research undertaken, most specifically the Somdance Manual by the University of Western Sydney, while directing focus to the first-year student transition from private dance studio training into the pre-professional arena.
Resumo:
Skin temperature is an important physiological measure that can reflect the presence of illness and injury as well as provide insight into the localised interactions between the body and the environment. The aim of this systematic review was to analyse the agreement between conductive and infrared means of assessing skin temperature which are commonly employed in in clinical, occupational, sports medicine, public health and research settings. Full-text eligibility was determined independently by two reviewers. Studies meeting the following criteria were included in the review: 1) the literature was written in English, 2) participants were human (in vivo), 3) skin surface temperature was assessed at the same site, 4) with at least two commercially available devices employed—one conductive and one infrared—and 5) had skin temperature data reported in the study. A computerised search of four electronic databases, using a combination of 21 keywords, and citation tracking was performed in January 2015. A total of 8,602 were returned. Methodology quality was assessed by 2 authors independently, using the Cochrane risk of bias tool. A total of 16 articles (n = 245) met the inclusion criteria. Devices are classified to be in agreement if they met the clinically meaningful recommendations of mean differences within ±0.5 °C and limits of agreement of ±1.0 °C. Twelve of the included studies found mean differences greater than ±0.5 °C between conductive and infrared devices. In the presence of external stimulus (e.g. exercise and/or heat) five studies foundexacerbated measurement differences between conductive and infrared devices. This is the first review that has attempted to investigate presence of any systemic bias between infrared and conductive measures by collectively evaluating the current evidence base. There was also a consistently high risk of bias across the studies, in terms of sample size, random sequence generation, allocation concealment, blinding and incomplete outcome data. This systematic review questions the suitability of using infrared cameras in stable, resting, laboratory conditions. Furthermore, both infrared cameras and thermometers in the presence of sweat and environmental heat demonstrate poor agreement when compared to conductive devices. These findings have implications for clinical, occupational, public health, sports science and research fields.
Resumo:
Green infrastructure is considered as a strategic approach to address the ecological and social impacts of urban sprawl. The main elements of green infrastructure have been well established and include a series of multifunctional ecological systems, such as green urban space, green road infrastructure and the links between these systems. However, it should be noted that the elements of green road infrastructure have only been briefly mentioned in isolated life cycle stages, e.g. design, procurement, construction, maintenance and operation. The definition of green road infrastructure and the elements in green road infrastructure projects remain largely unknown. To explore the elements in green road infrastructure, a critical review was adopted. As the development of green road infrastructure projects is guided by rating systems, a comparison of three major green roads rating systems, including GreenroadsTM, EnvisionTM and Infrastructure Sustainability Rating Tool—IS, was conducted. The comparison reveals that green roads can be defined as road projects that have superior performance in economic, social and environmental sustainability. The sustainability features in green roads mainly include environmental sustainability, social sustainability, economic sustainability, quality, pavement technology and innovation. The results will contribute to an increased understanding of green roads and will be useful to improve the performance of road projects on these sustainability features.
Resumo:
I approached the editorial prompt as an opportunity to work through some of the concerns driving my current research on creative labor in emergent or ‘peripheral’ media hubs, centers of production activity outside established media capitals that are nevertheless increasingly integrated into a global production apparatus. It builds from my research on the role that film, television and digital media production have played in the economic and cultural strategies of Glasgow, Scotland, and extends the focus on media work to other locations, including Prague and Budapest. I am particularly drawn to the spatial dynamics at play in these locations and how local producers, writers, directors and crew negotiate a sense of place and creative identity against the flows and counter-flows of capital and culture. This means not only asking questions about the growing ensemble of people, places, firms and policies that make international productions possible, but also studying the more quotidian relationships between media workers and the locations (both near and far) where they now find work. I do not see these tasks as unrelated. On the one hand, such queries underscore how international production depends on a growing constellation of interchangeable parts and is facilitated by various actors whose agendas may or may not converge. On the other hand, these questions also betray an even more complicated dynamic, a process that is shifting the spatial orientation of both location and labor around uneven and contested scales. As local industries reimagine themselves as global players, media practitioners are caught up in a new geography of creative labor: not only are personnel finding it increasingly necessary to hop from place to place to follow the work, but also place itself is changing, as locations morph into nebulous amalgamations of tax rebates, subsidized facilities, production services and (when it still matters) natural beauty.
Resumo:
In May 2011, the Australian Federal Education Minister announced there would be a unique, innovative and new policy of performance pay for teachers, Rewards for Great Teachers (Garrett, 2011a). In response, this paper uses critical policy historiography to argue that the unintended consequences of performance pay for teachers makes it unlikely it will deliver improved quality or efficiency in Australian schools. What is new, in the Australian context, is that performance pay is one of a raft of education policies being driven by the federal government within a system that constitutionally and historically has placed the responsibility for schooling with the states and territories. Since 2008, a key platform of the Australian federal Labor government has been a commitment to an Education Revolution that would promote quality, equity and accountability in Australian schools. This commitment has resulted in new national initiatives impacting on Australian schools including a high-stakes testing regime 14 National Assessment Program 13 Literacy and Numeracy (NAPLAN) 14a mandated national curriculum (the Australian Curriculum), professional standards for teachers and teacher accreditation 14Australian Institute for Teaching and School Leadership (AITSL) 14and the idea of rewarding excellent teachers through performance pay (Garrett, 2011b). These reforms demonstrate the increased influence of the federal government in education policy processes and the growth of a 1Ccoercive federalism 1D that pits the state and federal governments against each other (Harris-Hart, 2010). Central to these initiatives is the measuring, or auditing, of educational practices and relationships. While this shift in education policy hegemony from state to federal governments has been occurring in Australia at least since the 1970s, it has escalated and been transformed in more recent times with a greater emphasis on national human capital agendas which link education and training to Australia 19s international economic competitiveness (Lingard & Sellar, in press). This paper uses historically informed critical analysis to critique claims about the effects of such policies. We argue that performance pay has a detailed and complex historical trajectory both internationally and within Australian states. Using Gale 19s (2001) critical policy historiography, we illuminate some of the effects that performance pay policies have had on education internationally and in particular within Australia. This critical historical lens also provides opportunities to highlight how teachers have, in the past, tactically engaged with such policies.
Rainfall variability drives interannual variation in N2O emissions from a humid, subtropical pasture
Resumo:
Variations in interannual rainfall totals can lead to large uncertainties in annual N2O emission budget estimates from short term field studies. The interannual variation in nitrous oxide (N2O) emissions from a subtropical pasture in Queensland, Australia, was examined using continuous measurements of automated chambers over 2 consecutive years. Nitrous oxide emissions were highest during the summer months and were highly episodic, related more to the size and distribution of rain events than soil water content. Over 48% of the total N2O emitted was lost in just 16% of measurement days. Interannual variation in annual N2O estimates was high, with cumulative emissions increasing with decreasing rainfall. Cumulative emissions averaged 1826.7 ± 199.9 g N2O-N ha−1 yr−1 over the two year period, though emissions from 2008 (2148 ± 273 g N2O-N ha−1 yr−1) were 42% higher than 2007 (1504 ± 126 g N2O-N ha−1 yr−1). This increase in annual emissions coincided with almost half of the summer precipitation from 2007 to 2008. Emissions dynamics were chiefly driven by the distribution and size of rain events which varied on a seasonal and annual basis. Sampling frequency effects on cumulative N2O flux estimation were assessed using a jackknife technique to inform future manual sampling campaigns. Test subsets of the daily measured data were generated for the pasture and two adjacent land-uses (rainforest and lychee orchard) by selecting measured flux values at regular time intervals ranging from 1 to 30 days. Errors associated with weekly sampling were up to 34% of the sub-daily mean and were highly biased towards overestimation if strategically sampled following rain events. Sampling time of day also played a critical role. Morning sampling best represented the 24 hour mean in the pasture, whereas sampling at noon proved the most accurate in the shaded rainforest and lychee orchard.
Resumo:
Hot air ballooning incidents are relatively rare; however, they have a high potential to be fatal. In order to inform appropriate safety interventions it is first necessary to understand the causal factors which lead to incidents and near-misses, which requires a formal incident report database. The Australian Balloon Federation (ABF) advocates the reporting of recreational hot air ballooning incidents, by reporting directly to the ABF safety officer or by completing an online incident report form. The objective of this paper is to understand how widely used the reporting system is and whether there are any perceived barriers to reporting. Sixty-nine balloonists participated in an online survey about their experience of incident reporting. Survey respondents were mostly male (11 female), experienced balloonists (mean years’ experience ballooning 19.51y with a SD 11.19). Sixty respondents (87%) held a pilot license. The majority (82.6%) of respondents were aware of the ABF incident reporting system. Over half (62.3%) had been involved in a ballooning incident or near-miss in Australia. However, 40% of those who had an incident or near-miss did not report it to the ABF and only 15.9% of all those surveyed had used the online incident report form. There was some disagreement regarding when it was appropriate to report an incident or near miss. Some respondents felt an incident or near miss should only be reported if it resulted in injury or damage, while others said near-misses should also be reported. The most frequent barriers identified were: a lack of understanding of when to report to the ABF; trivializing of incidents; and concerns about the system itself Steps should be taken to increase understanding of the system purpose and long term benefits. Specifically, reporting near-misses should be encouraged. This study is significant because it is the first to examine reporting practices in non-motorised recreational aviation.
Resumo:
Background: The critical care context presents important opportunities for nurses to deliver skilled, comprehensive care to patients at the end of life and their families. Limited research has identified the actual end-of-life care practices of critical care nurses. Objective: To identify the end-of-life care practices of critical care nurses. Design: A national cross-sectional online survey. Methods: The survey was distributed to members of an Australian critical care nursing association and 392 critical care nurses (response rate 25%) completed the survey. Exploratory factor analysis using principal axis factoring with oblique rotation was undertaken on survey responses to identify the domains of end-of-life care practice. Descriptive statistics were calculated for individual survey items. Results: Exploratory factor analysis identified six domains of end-of-life care practice: information sharing, environmental modification, emotional support, patient and family centred decision-making, symptom management and spiritual support. Descriptive statistics identified a high level of engagement in information sharing and environmental modification practices and less frequent engagement in items from the emotional support and symptom management practice areas. Conclusions: The findings of this study identified domains of end-of-life care practice, and critical care nurse engagement in these practices. The findings highlight future training and practice development opportunities, including the need for experiential learning targeting the emotional support practice domain. Further research is needed to enhance knowledge of symptom management practices during the provision of end-of-life care to inform and improve practice in this area.
Resumo:
Due to ever increasing climate instability, the number of natural disasters affecting society and communities is expected to increase globally in the future, which will result in a growing number of casualties and damage to property and infrastructure. Such damage poses crucial challenges for recovery of interdependent critical infrastructures. Post-disaster reconstruction is a complex undertaking as it is not only closely linked to the well-being and essential functioning of society, but also requires a large financial commitment. Management of critical infrastructure during post-disaster recovery needs to be underpinned by a holistic recognition that the recovery of each individual infrastructure system (e.g. energy, water, transport and information and communication technology) can be affected by the interdependencies that exist between these different systems. A fundamental characteristic of these interdependencies is that failure of one critical infrastructure system can result in the failure of other interdependent infrastructures, leading to a cascade of failures, which can impede post-disaster recovery and delay the subsequent reconstruction process. Consequently, there is a critical need for developing a holistic strategy to assess the influence of infrastructure interdependencies, and for incorporating these interdependencies into a post-disaster recovery strategy. This paper discusses four key dimensions of interdependencies that need to be considered in a post-disaster reconstruction planning. Using key concepts and sub-concepts derived from the notion of interdependency, the paper examines how critical infrastructure interdependencies affect the recovery processes of damaged infrastructures.