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861.
With a significant list of achievements in traffic safety over some 40 years, Australia’s most successful initiatives have emerged from consideration of the scientific basis for achieving effective results. Over time, the increasing use of scientific methods has matured to an extent whereby road safety strategies for entire jurisdictions are now being formed and optimised on the basis of evidence-based mathematical modelling of predicted strategy performance over periods of ten or more years ahead. This paper describes the approach used in the State of Western Australia (WA) to support the development of its new strategy, ‘Towards Zero’, addressing the 12-year period from 2008 to 2020. Also described is the early development of the modelling approach in the State of Victoria, Australia, subsequently applied, refined and adapted to Western Australia. The ‘Towards Zero’ strategy aims to ensure that road safety policies continue to evolve within a strategic framework, based on Australasia’s Safe System framework, which was derived from the best elements of the Swedish Vision Zero and the Dutch Sustainable Safety visions.The process for the development of the strategy involved a greater degree of community and stakeholder engagement than has been the case previously, based on the fundamental belief that the community should be provided with the best evidence about what works no matter how controversial, so that it can debate and consider the options available to improve safety.It is equally important to have a strategy based on the best possible evidence. The Monash University Accident Research Centre (MUARC) was appointed by the WA Office of Road Safety to identify, describe and recommend proven counter-measures within the Safe System framework and develop a series of scientifically sound directions and options.This paper outlines the modelling technique used by MUARC along with results and summarises the community consultation process.  相似文献   
862.
Rapid bioassessment (RBA) techniques for evaluating river health are now commonplace and there is much debate on the best methods that should be used. One of the important features of RBA is subsampling of large qualitative or semi-quantitative samples to reduce the costs associated with handling and identifying animals. In Australia, the Australian River Assessment System (known as “AusRivAS”) has been widely used since 1994 to monitor and assess river health. To test the efficacy of AusRivAS protocols, four live-sorting protocols, the standard Australian River Assessment Scheme (AusRivAS) and three suggested improvements, were evaluated in three habitat types and in clear and turbid rivers. The suggested improvements included using magnification during the live-sort process, separate sorting of coarse and fine fractions and increasing the amount of time or animals collected. There was no statistically significant difference between any of the trialed live-sort protocols in terms of the number of taxa collected compared to the number remaining, the community composition, the abundances of individual families collected, or the AusRivAS Observed/Expected taxa ratios. The lack of differences between the live-sort protocols suggests that technicians using the current standard AusRivAS protocols are able to effectively obtain a representative subsample of animals from the whole kick or sweep net qualitative sample. This has the advantage of cost savings because no retraining will be required, field procedures will remain uncomplicated and previous river health assessments will remain valid.  相似文献   
863.
Personal and area samples for airborne lead were taken at a lead mine concentrator mill, and at a lead-acid battery recycler. Lead is mined as its sulfidic ore, galena, which is often associated with zinc and silver. The ore typically is concentrated, and partially separated, on site by crushing and differential froth flotation of the ore minerals before being sent to a primary smelter. Besides lead, zinc and iron are also present in the airborne dusts, together with insignificant levels of copper and silver, and, in one area, manganese. The disposal of used lead-acid batteries presents environmental issues, and is also a waste of recoverable materials. Recycling operations allow for the recovery of lead, which can then be sold back to battery manufacturers to form a closed loop. At the recycling facility lead is the chief airborne metal, together with minor antimony and tin, but several other metals are generally present in much smaller quantities, including copper, chromium, manganese and cadmium. Samplers used in these studies included the closed-face 37 mm filter cassette (the current US standard method for lead sampling), the 37 mm GSP or "cone" sampler, the 25 mm Institute of Occupational Medicine (IOM) inhalable sampler, the 25 mm Button sampler, and the open-face 25 mm cassette. Mixed cellulose-ester filters were used in all samplers. The filters were analyzed after sampling for their content of the various metals, particularly lead, that could be analyzed by the specific portable X-ray fluorescence (XRF) analyzer under study, and then were extracted with acid and analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES). The 25 mm filters were analyzed using a single XRF reading, while three readings on different parts of the filter were taken from the 37 mm filters. For lead at the mine concentrate mill, all five samplers gave good correlations (r2 > 0.96) between the two analytical methods over the entire range of found lead mass, which encompassed the permissible exposure limit of 150 mg m(-3) enforced in the USA by the Mine Safety and Health Administration (MSHA). Linear regression on the results from most samplers gave almost 1 ratio 1 correlations without additional correction, indicating an absence of matrix effects from the presence of iron and zinc in the samples. An approximately 10% negative bias was found for the slope of the Button sampler regression, in line with other studies, but it did not significantly affect the accuracy as all XRF results from this sampler were within 20% of the corresponding ICP values. As in previous studies, the best results were obtained with the GSP sampler using the average of three readings, with all XRF results within 20% of the corresponding ICP values and a slope close to 1 (0.99). Greater than 95% of XRF results were within 20% of the corresponding ICP values for the closed-face 37 mm cassette using the OSHA algorithm, and the IOM sampler using a sample area of 3.46 cm2. As in previous studies, considerable material was found on the interior walls of all samplers that possess an internal surface for deposition, at approximately the same proportion for all samplers. At the lead-acid battery recycler all five samplers in their optimal configurations gave good correlations (r2 > 0.92) between the two analytical methods over the entire range of found lead mass, which included the permissible exposure limit enforced in the USA by the Occupational Safety and Health Administration (OSHA). Linear regression on the results from most samplers gave almost 1 ratio 1 correlations (except for the Button sampler), indicating an absence of matrix effects from the presence of the smaller quantities of the other metals in the samples. A negative bias was found for the slope of the button sampler regression, in line with other studies. Even though very high concentrations of lead were encountered (up to almost 6 mg m(-3)) no saturation of the detector was observed. Most samplers performed well, with >90% of XRF results within +/- 25% of the corresponding ICP results for the optimum configurations. The OSHA algorithm for the CFC worked best without including the back-up pad with the filter.  相似文献   
864.
Should north Australia’s extensive populations of feral animals be eradicated for conservation, or exploited as a rare opportunity for Indigenous enterprise in remote regions? We examine options for a herd of banteng, a cattle species endangered in its native Asian range but abundant in Garig Gunak Barlu National Park, an Aboriginal land managed jointly by traditional owners and a conservation agency in the Northern Territory of Australia. We reflect on the paradoxes that arise when trying to deal effectively with such complex and contested issues in natural resource management using decision-support tools (ecological-economic models), by identifying the trade-offs inherent in protecting values whilst also providing incomes for Indigenous landowners.  相似文献   
865.

Robust decision making, a growing approach to infrastructure planning under climate change uncertainty, aims to evaluate infrastructure performance across a wide range of possible conditions and identify the most robust strategies and designs. Robust decision making seeks to find potential weaknesses in systems in order to gird these through a combination of policy, infrastructure, and, in some cases, resilient or recovery strategies. A system can be explored by simulating many combinations of uncertain climatic and economic parameters; statistical clustering can identify parameter thresholds that lead to unacceptable performance. Often, however, uncertain variables are correlated, complicating the robustness analysis and casting doubt upon the thresholds identified. Here, we evaluate the impact of ordinary, hidden correlations in uncertainty parameters that drive simulation in robust decision making. We induced correlations between temperature and key climatic and economic parameters. We tested correlations of 0%, 30%, 60%, and 90% between temperature and the absolute value of precipitation, coefficient of variation, and downward surface solar radiation, and negative correlations between temperature and net variable benefit and the discount rate. We used a calibrated simulation model of a dam system regulating Lake Tana, Ethiopia, to compute the agricultural supply and net present value of the reservoirs. As the correlation strength increased, the results converged in a smaller region. We found that strong correlations depressed robustness scores of lower-performing alternatives and conversely increased results of the higher-performing alternatives. As the correlations increased in favorable alternatives, the failure thresholds became more extreme, speciously suggesting that only intense changes would result in poor performance. This overall analysis highlights the degree to which correlations of an interconnected climatic and economic system can impact outcomes of robust decision making and suggests methods to avoid confounding results.

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