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Queensland Rail, also known as QR, is a railway operator in the state of Queensland, Australia. Owned by the Queensland Government, Queensland Rail operates suburban and long-distance passenger services. It also owns and maintains approximately 8,000 kilometres of track. Wikipedia.

Lee P.J.,University of Canterbury | Vitkovsky J.P.,Queensland Government
Journal of Hydraulic Engineering | Year: 2010

The unsteady mass and momentum equations for pipe flow can be solved in the frequency domain and provides additional insight into the behavior of fluid transients. Additionally, this approach has significant computational advantages compared to the method of characteristics because it is not based on a rigid time-space grid. Despite its advantages, the frequency domain approach must be used with care as it uses linearized forms of the steady friction and orifice equations-which can deviate significantly from the true nonlinear solution. The conditions in which the frequency response method can be accurately used are currently unknown. This paper investigates and quantifies the error in the frequency-domain method, via comparison to a highly discretized time-domain model that uses the method of characteristics, and describes situations where the frequency response method can be used with accurate results. A reservoir-pipe-valve system was used in this study with transients generated by perturbation of the valve. The error consists of errors from two sources: the linear approximations of the steady friction and the steady orifice equations. The frequency response method was shown to produce identical results to the method of characteristics when these two sources of error are minimized. The error in the frequency-domain model was quantified as functions of the perturbation magnitude, frequency, and system parameters. The results indicate that errors are significant when the perturbation size is more than 25% of the steady-state condition and this error is frequency dependent with the largest errors occurring at the harmonic peaks of the system. © 2010 ASCE. Source

Beswick R.,University of Queensland | Beswick R.,Queensland Government | Driscoll C.,University of Queensland | Kei J.,University of Queensland
Ear and Hearing | Year: 2012

Objectives: The aim of this study was to investigate whether there was evidence-based support for targeted surveillance programs using a risk-factor registry to detect postnatal hearing loss or whether other programs were available that may be more effective than targeted surveillance. Particularly, it addressed questions that arose along the targeted surveillance pathway, including: (1) the risk factors used to determine a referral, (2) referral frequencies, (3) the relationship between risk factors and a postnatal hearing loss, and (4) other systems that may be more efficient than the use of risk factors. Design: A systematic literature review was completed in peer-reviewed and non-peer-reviewed databases. Methods: Publications were obtained using the databases MEDLINE, Cumulative Index of Nursing and Allied Health Literature, and Excerpta Medica on line, and by inspecting the reference lists of relevant articles and expert-committee papers. Quality assessment ratings and data extraction were completed by the research team. Results: In total, 40 articles met the inclusion criteria and were included in this review. The outcomes drawn from these studies were inconclusive as they were based on small sample sizes and largely from single sites only. With this in mind, from the information obtained: (1) gestational age, low-birth weight, toxoplasmosis, other infections, rubella, cytomegalovirus (CMV), herpes simplex virus infections, craniofacial anomalies, respirator support, and the administration of aminoglycosides were the more commonly reported risk factors in programs; (2) referral frequency for monitoring appointments was approximately 3%; and (3) CMV, extracorporeal membrane oxygenation, congenital diaphragmatic hernia, and persistent pulmonary hypertension of the newborn were associated with postnatal hearing loss, whereas, preauricular skin tags and ear pits, low-birth weight, and toxoplasmosis were not. The review also identified that second-phase universal screening programs, CMV screening, and genetic screening should be explored as potential additions or alternatives to targeted surveillance using risk factors. Conclusions: Further large-scale, population-based research on available programs for the detection of postnatal hearing loss should be conducted to improve present practice and assist with the development of evidence-based guidelines for hearing monitoring. Copyright © 2012 by Lippincott Williams & Wilkins • Printed in the U.S.A. Source

Vreugdenburg T.D.,University of Adelaide | Willis C.D.,University of Adelaide | Willis C.D.,University of British Columbia | Mundy L.,Queensland Government | Hiller J.E.,Australian Catholic University
Breast Cancer Research and Treatment | Year: 2013

The objective of this study aimed to systematically identify and evaluate all the available evidence of safety, effectiveness and diagnostic accuracy for three emerging classes of technology promoted for breast cancer screening and diagnosis: Digital infrared thermal imaging (DITI), electrical impedance scanning (EIS) and elastography. A systematic search of seven biomedical databases (EMBASE, PubMed, Web of Science, CRD, CINAHL, Cochrane Library, Current Contents Connect) was conducted through March 2011, along with a manual search of reference lists from relevant studies. The principal outcome measures were safety, effectiveness, and diagnostic accuracy. Data were extracted using a standardised form, and validated for accuracy by the secondary authors. Study quality was appraised using the quality assessment of diagnostic accuracy studies tool, while heterogeneity was assessed using forest plots, Cooks' distance and standardised residual scatter plots, and I2 statistics. From 6,808 search results, 267 full-text articles were assessed, of which 60 satisfied the inclusion criteria. No effectiveness studies were identified. Only one EIS screening accuracy study was identified, while all other studies involved symptomatic populations. Significant heterogeneity was present among all device classes, limiting the potential for meta-analyses. Sensitivity and specificity varied greatly for DITI (Sens 0.25-0.97, Spec 0.12-0.85), EIS (Sens 0.26-0.98, Spec 0.08-0.81) and ultrasound elastography (Sens 0.35-1.00, Spec 0.21-0.99). It is concluded that there is currently insufficient evidence to recommend the use of these technologies for breast cancer screening. Moreover, the high level of heterogeneity among studies of symptomatic women limits inferences that may be drawn regarding their use as diagnostic tools. Future research employing standardised imaging, research and reporting methods is required. © 2013 Springer Science+Business Media New York. Source

Clemens S.,Queensland Government
Quality of life research : an international journal of quality of life aspects of treatment, care and rehabilitation | Year: 2014

To provide population norms for the EQ-5D-3L by age and gender based on a representative adult sample in Queensland, Australia; to assess differences in health-related quality of life by applying the Australian, UK and USA value sets to these data; and to assess differences in utility scores for key preventive health indicators. A cross-sectional computer-assisted telephone interview survey (March-June 2011) with 5,555 adults. Respondents rated their impairment (none, moderate, severe problems) across five domains (mobility, self-care, usual activities, pain and discomfort, anxiety or depression) using the validated EQ-5D-3L health-related quality of life instrument. Utility score indexes were derived using the Australian, UK and USA value sets. Forty per cent of adults reported pain and discomfort while 3% indicated problems with self-care. Approximately one in six had limitations with mobility, usual activities or anxiety or depression. The three value sets performed similarly in discriminating differences based on most characteristics, and clinically meaningful differences were seen for age, body weight, physical activity and daily smoking. There were no differences in utility scores for gender. This is the first study to report general population findings for the Australian EQ-5D-3L value set. Overall, the Australian value set performed comparably with other value sets commonly used in the Australian population; however, differences were observed. Results will enable further refinement to health and economic studies in an Australian-specific context. Source

Weber L.C.,University of Queensland | Vanderwal J.,James Cook University | Schmidt S.,University of Queensland | Mcdonald W.J.F.,Queensland Government | And 2 more authors.
Journal of Biogeography | Year: 2014

Aim: Our aims were to identify centres of endemism and to infer whether these areas have functioned as refugia for subtropical rain forest plants through historical climate fluctuations. Location: Subtropical eastern Australia (23-33° S; 145-155° E). Methods: We collated 25,000 records of 179 endemic rain forest plants to identify geographical areas with unusually high concentrations of endemic taxa and range-restricted endemics. We then tested whether centres of endemism coincide with other features indicating refugia, including habitat stability over 120,000 years, and we related dispersal patterns to past habitat stability using seed weight as a surrogate for dispersal ability of endemic plant taxa. Results: We identified five main centres of endemism. Historical stability and other processes affecting diversity, including current rainfall, rain forest area, and topographic complexity, explained 58% of variation in plant-weighted endemism. Taxa with poor dispersal ability were concentrated in the areas that were most stable historically. Main conclusions: Several lines of evidence suggest that centres of endemism have functioned as important refugia for subtropical rain forest taxa through historical climate fluctuations. The highest concentrations of range-restricted endemic species occur in locations that are predicted to have maintained stable rain forest habitat over at least the past 120,000 years. This association was independent from other factors that were expected to promote diversity (i.e. rain forest area and current environmental suitability). These locations have disproportionately high concentrations of species with poor dispersal ability (large-seeded species). © 2013 John Wiley & Sons Ltd. Source

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