77 resultados para Ascertainment of demand


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A criterion for selecting a coating for an energy pipeline is that the coating should have a suitable flexibility to meet the high strain demand during hydrostatic testing and during field bending. This requires knowledge of the level of strain demand for the pipeline, and also the maximum strain that could be
tolerated by the coating system. Whereas average strains imposed during manufacturing and construction are reasonably well predicted, there is insufficient understanding on the factors leading to localised deformation of the pipe. Significant work has been carried out in the past to develop tests for assessing
the coatings’ ability to handle a certain amount of strain based on bend testing, tensile testing and burst testing. However, there is a concern as to whether these tests properly represent localised micro-strains associated with construction activities including field bending and pressure testing, particularly pressure testing of pipelines designed for operation at 80% of specified minimum yield strength (SMYS). Consequently coatings considered "suitable" for modern pipelines may fail. The first issue discussed in this paper is main factors affecting strain localisation. The non-deterministic distributions of heterogeneities over the pipe provide a ground to consider the mechanisms of localisation as a stochastic process. An approach is proposed to quantify the maximum localised strain demand through cold field bending and hydrostatic experiments. Another issue discussed in this paper is the experimental assessment of coating flexibility under the effects of localised strains. Preliminary mandrel tests have been carried out to assess the uniformity of the imposed strain. Although mandrel testing has been shown to be a useful method for relative comparison of coating flexibility, it has several weaknesses that could significantly affect the reliability and reproducibility of the results.

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The implementation of the Green Skills Agreement ratified by the Council of Australian Governments (COAG) in 2010 provides the national policy context for this analysis of skills for sustainability. Data from three different but complementary studies provide powerful insight into the attitudes and perceptions of young people who are studying, or are recent graduates of, Australian Vocational Education and Training (VET) programs. We argue that the voices of the young people who participate as students are largely absent from analysis and policy-making, despite policy rhetoric about a demand driven Australian tertiary education sector responsive to consumer (student) interest and need. The combination of these three studies contributes to an improved understanding of what these young adults think and are learning with regard to skills for sustainability in their VET courses and in their workplaces. Most notably, these VET students reported that increasingly changes around skills for sustainability are being implemented into both their work roles and their courses of study.