2,714 research outputs found

    Nature-based solutions forming urban intervention approaches to anthropogenic climate change:a quantitative literature review

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    Discussion around anthropogenic climate change has occurred for over 100 years. However, in recent decades, these discussions have intensified due to increased confidence in scientific research highlighting adverse effects, increased knowledge breadth in climate science, and heightened public and political awareness and engagement on the topic. Climate change is now acknowledged as one of the biggest challenges and threats to modern lifestyles. Nature-based solutions (NBS), as a mediator and mitigator to adverse climate change effects, is an emerging area of expanding research collateral and practitioner literacy. To highlight current NBS knowledge, existing knowledge gaps, and research trends, a Quantitative Systematic Literature Review (QSLR) was undertaken (n = 54). This QSLR reveals the short temporal span of articles relating to NBS as a response to climate change, with most articles being of a research style format. NBS research focus areas were found to be dominated by ecological and infrastructure approaches to climate change mitigation, and ecological and technical positions were found to be most topical across the current climate change literature. Multiple knowledge gaps were identified by the review, namely the lack of broader conceptual approaches and knowledge acquisition regarding climate change responses via NBS, as well as the psychological relationship humans share with NBS and climate change, adverse or otherwise. These knowledge gaps highlight where future research inquiry may be directed to increase the value and completion of this research area. It is hoped that this QSLR will assist in increasing the profile of NBS in the multidisciplinary and complex response to anthropogenic climate change, as well as contribute to the growth in investment and implementation of NBS assets for a rigid and resilient global future

    The Research Excellence Framework (REF): Assessing the impact of social work research on society

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    This paper reviews one aspect, impact, of the forthcoming assessment of research in UK universities, the Research Excellence Framework (REF), and examines its meaning and potential for enhanced partnerships between social work practice and academia in the context of the current economic crisis. Examples of case studies being developed to show how research has societal impact are described and some of the complexities of what, on the surface appears to echo social work 19s desire to make a positive difference to the lives of people in society, are drawn out. The importance of the REF for the integration of social work practice and academia have been rehearsed many times. This paper argues that making an impact is everybody 19s concern and practitioners and those who use social work services and their carers have a role to play in its creation and identification

    Misfit strain relaxation and dislocation formation in supercritical strained silicon on virtual substrates

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    Relaxation of strained silicon on 20% linear graded virtual substrates was quantified using high resolution x-ray diffraction and a defect etching technique. The thickness of strained silicon was varied between 10 and 180 nm. Relaxation was observed in layers below the critical thickness but increased to only 2% relaxation in the thickest layers even with annealings up to 950 Ā°C. Cross-sectional transmission electron microscopy revealed stacking faults present in layers thicker than 25 nm, and nucleated 90Ā° Shockley partial dislocations forming microtwins in the thickest layer. These features are implicated in the impediment of the relaxation process

    ā€˜River! that in silence windestā€™ The place of religion and spirituality in social work assessment: sociological reflections and practical implications

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    This paper explores the place of religion and spirituality in social work assessment. Place represents a topographic or locational concept that suggests an embeddedness within a physically bounded space, implying here that religion and spirituality are centrally important to the lives of many people and therefore necessarily part of the social work relationship between practitioners and their clients or service users. A range of concepts and implications arising from the idea that religion and spirituality form a necessary part of quotidian social work practice require some discussion. First of all we must recognize that religion and spirituality are often seen as synonyms and we must first discuss this and suggest discrete definitions of each concept. We also need to discuss assessment itself in social work, recognising the power relations and potential for the normative imposition of unspoken and taken-for-granted assumptions in making judgements about vulnerable peopleā€™s ecologies and psychologies. This is problematised further when we consider questions of vulnerability ā€“ a contested term in itself; who makes someone vulnerable, is it a quality or characteristic or does it reflect something structural, or both? Social work may be considered as a locally contextualized set of processes or moral practices that make statements about assumed vulnerabilities. We are taking this further by asking about religion and spirituality as one aspect of this collection of processes. This may project social work as both homogeneous, transferable and globally understood, an idea we will need to debate. Accepting that all these concepts may be contested and problematic we can move forward to consider ways in which religion and spirituality may be assessed in social work, making reference predominantly to UK and US social work whilst being tentative in making any normative assumptions about this exploration. A number of models will be introduced, drawing out some of the potential meanings and consequences of these for interpersonal relationship and also for peopleā€™s spiritual perspectives. A case example of the exclusion of religion and spirituality, notably Christianity, from UK social work in the recent past will be provided. This background prepares us for moving towards a sociological analysis of the state of play

    Factors contributing to heat affected zone damage in Grade 91 steel feature type cross-weld tests

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    Grade 91 steel has been widely utilized in power plants over the last 20 years. Its specification worldwide has dramatically increased since the acceptance of ASME Code Case 1943 for this material in 1983. Recent evaluation of a combination of ex-service Grade 91 steel components and virgin material has provided a unique opportunity to revisit commonly stated factors which contribute to damage in cross-weld creep tests. The approach adopted here is grounded in the fundamental objective of linking metallurgical risk factors in Grade 91 steel to the cross-weld creep performance. Establishing metallurgical risk factors in 9%Cr steels is regarded as a key consideration in the integration of a well-engineered life management strategy for these complex materials. In this study, two heats of ex-service Grade 91 steel which exhibit a similar response to the deformation resistance (i.e. strength) but dramatic differences in the susceptibility to damage (i.e. creep ductility) were evaluated in the welded condition using large, feature type cross-weld creep samples. Heat affected zone damage was investigated from both a macro-damage and micro-damage perspective. The macro-damage evaluation provided a comprehensive understanding of the global damage distribution through the heat affected zone (HAZ). The damage was linked to extensive hardness mapping and calculated peak temperatures through the HAZ. The microdamage characterization included a number of local observations for cavities in each sample using scanning electron microscope techniques. General observations were made regarding the shape and size of creep cavities and association of damage with microstructural features. These observations were linked to the as-fabricated microstructure and as characterized by electron backscatter diffraction (EBSD) and energy dispersive x-ray spectroscopy (EDS) mapping

    Cross-weld creep performance in grade 91 steel: Macro-based assessment

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    Meaningful characterization of the microstructure in metallurgically complex steels is complicated by the diversity of thermal cycles experienced by multipass fusion welds. To overcome the problems of relevant documentation, it is necessary to balance information from macro-, micro-, and nano-evaluation with appropriate analysis. This paper presents details regarding recommended approaches that optimize this characterization. Initially, specific procedures relevant to macroanalysis, including hardness mapping and calculation of the peak temperature through the width of the heat-affected zone (HAZ), are described. Then, assessment of the distribution of creep damage in feature-type, cross-weld creep tests using laser microscopy is detailed. Using these methods, the extent of damage through the HAZ was compared to the local reduction in the HAZ hardness and to the calculated peak temperatures in the HAZ. The implications of these findings are discussed with respect to damage, deformation, and sample geometry

    Linking performance of parent Grade 91 steel to the cross-weld creep performance using feature type tests

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    Grade 91 steel has been widely utilized in power plants over the last 20 years. Its specification worldwide has dramatically increased since the acceptance of Code Case 1943 for this material in 1983. Recent evaluation of a combination of ex-service Grade 91 steel components and virgin material has provided a unique opportunity to independently assess the performance of a combination of base metal and weldments. This approach has been grounded in the fundamental objective of linking metallurgical risk factors in Grade 91 steel to the cross-weld creep performance. Establishing critical risk factors in 9Cr steels is regarded as a key consideration in the integration of a meaningful life management strategy for these complex steels. The potential metallurgical risk factors in Grade 91 steel have been fundamentally divided into factors which affect strength, ductility or both. In this study, two heats of ex-service Grade 91 steel which exhibit dramatic differences in strength and ductility have been evaluated in the exservice condition and re-heat treated to establish a relevant set of strength:ductility variables. This set of variables includes [strength:ductility]: low:low, medium:low, low:high and medium:high. The influence of these strength:ductility variables were investigated for feature type cross-weld creep tests to better evaluate the influence of the initial base material condition on cross-weld creep performance

    A Real Time Optical Biosensor Assay for Amoxicillin and Other Ī²-Lactams in Water Samples

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    Antibiotic contamination of drinking water and sewage is a matter of environmental and public health concern. Traditionally, ELISA or HPLC methods have been used to detect and measure antibiotic contamination. By applying an optical biosensing method, biolayer inteferometry (BLI), we have developed a kinetic competition binding assay capable of quantitating less than 1ppm (~33 Ī¼M) amoxicillin. Similar to surface plasmon resonance, BLI senses changes that occur upon binding of one molecule to another near a surface to measure association and dissociation. Immobilized amoxicillin was used to screen for binding against an analyte solution of anti-amoxicillin equilibrated with amoxicillin-containing water samples, yielding binding that fit a one-state model. Maximal binding correlated highly with amoxicillin concentration. Simplified analysis of samples from water and sewage treatment plants in Georgia allowed quantitation without kinetic modeling. The assay is sensitive, cost-effective, fast and readily adaptable to a variety of samples and other small molecules

    Output Mode Switching for Parallel Five-bar Manipulators Using a Graph-based Path Planner

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    The configuration manifolds of parallel manipulators exhibit more nonlinearity than serial manipulators. Qualitatively, they can be seen to possess extra folds. By projecting such manifolds onto spaces of engineering relevance, such as an output workspace or an input actuator space, these folds cast edges that exhibit nonsmooth behavior. For example, inside the global workspace bounds of a five-bar linkage appear several local workspace bounds that only constrain certain output modes of the mechanism. The presence of such boundaries, which manifest in both input and output projections, serve as a source of confusion when these projections are studied exclusively instead of the configuration manifold itself. Particularly, the design of nonsymmetric parallel manipulators has been confounded by the presence of exotic projections in their input and output spaces. In this paper, we represent the configuration space with a radius graph, then weight each edge by solving an optimization problem using homotopy continuation to quantify transmission quality. We then employ a graph path planner to approximate geodesics between configuration points that avoid regions of low transmission quality. Our methodology automatically generates paths capable of transitioning between non-neighboring output modes, a motion which involves osculating multiple workspace boundaries (local, global, or both). We apply our technique to two nonsymmetric five-bar examples that demonstrate how transmission properties and other characteristics of the workspace can be selected by switching output modes.Comment: 7 pages, 6 figure
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