9,300 research outputs found

    Quiet propulsive lift for commuter airlines

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    The performance of STOL or RTOL aircraft and NASA's research program to provide options for future design and certification of quiet propulsive-life transports is described

    Maintaining environmental values in a commercial environment : a framework for commercial development in Victoria's national parks

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    This research has focussed on the development of a commercial business model (CBM) for providing tourism and support service based commercial activities in Victoria's national parks which also allowed for the protection of the parks natural values. National parks are vital if we as a nation are to retain our natural heritage - but the public sector land stewards of these important assets are facing increasing funding and user pressures. The result is a growing focus on the commercialisation of our national parks to provide services and generate the revenue required to maintain these assets. However, this has resulted in the exacerbation of a long existing conflict - these commercial operators are primarily focus on the achievement of a commercial return, while the land stewards' main responsibility is in the protection of the natural values of these assets. In completing this project an abductive research approach (using grounded theory) has been adopted. Specifically, the research activities undertaken included data collection via a number of techniques including stakeholder interviews, detailed examination of existing commercial arrangements, literature research on international approaches and models, development of a suggested commercial business model based on a synthesise of the research outcomes and, finally, obtaining user feedback. The use of the various data sources, and subsequent sourcing of user feedback facilitated the triangulation of the research results. The findings from this research challenge a number of the practices currently adopted in the structuring of commercial activities suggesting that these practices are inhibiting the quality of the service being provided to the national park visitor along with the level of protection being afforded to the parks natural values. The resulting CBM provides park managers with a framework for identification and structuring of commercial business activities, practical guidance on the actions required in the completion of a concession process and identification of a number of the relevant issues which need to be considered and addressed in establishing and managing a national park concession. The CBM has been developed specifically for application within Victoria's national parks (based on a public/private sector relationship). The output will also provide guidance on methods for embedding natural values on public/private sector relationships in other settings

    Marine Benthic Habitat Mapping of Muir Inlet, Glacier Bay National Park and Preserve, Alaska With an Evaluation of the Coastal and Marine Ecological Classification Standard III

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    Seafloor geology and potential benthic habitats were mapped in Muir Inlet, Glacier Bay National Park and Preserve, Alaska, using multibeam sonar, ground-truth information, and geological interpretations. Muir Inlet is a recently deglaciated fjord that is under the influence of glacial and paraglacial marine processes. High glacially derived sediment and meltwater fluxes, slope instabilities, and variable bathymetry result in a highly dynamic estuarine environment and benthic ecosystem. We characterize the fjord seafloor and potential benthic habitats using the Coastal and Marine Ecological Classification Standard (CMECS) recently developed by the National Oceanic and Atmospheric Administration (NOAA) and NatureServe. Substrates within Muir Inlet are dominated by mud, derived from the high glacial debris flux. Water-column characteristics are derived from a combination of conductivity temperature depth (CTD) measurements and circulation-model results. We also present modern glaciomarine sediment accumulation data from quantitative differential bathymetry. These data show Muir Inlet is divided into two contrasting environments: a dynamic upper fjord and a relatively static lower fjord. The accompanying maps represent the first publicly available high-resolution bathymetric surveys of Muir Inlet. The results of these analyses serve as a test of the CMECS and as a baseline for continued mapping and correlations among seafloor substrate, benthic habitats, and glaciomarine processes

    An overview of the quiet short-haul research aircraft program

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    An overview of the Quiet Short Haul Research Aircraft (QSRA) Program is presented, with special emphasis on its propulsion and acoustic aspects. A description of the NASA technical participation in the program including wind tunnel testing, engine ground tests, and advanced aircraft simulation is given. The aircraft and its systems are described and, measured performance, where available, is compared to program goals. Preliminary data indicate that additional research and development are needed in some areas of which acoustics is an example. Some of these additional research areas and potential experiments using the QSRA to develop the technology are discussed. The concept of the QSRA as a national flight research facility is explained

    Placing the university: thinking in and beyond globalization

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    In some respects, the impact of globalization on universities is well rehearsed (competition for international students; the drive for status in global rankings; the opening of overseas campuses; the dream of massive open online courses and other forms of digital education), but the relationship between universities as place-based institutions and globalization is less well understood. It is on that this chapter focuses. Drawing on work undertaken as part of an Economic and Social Research Council project (“Higher Education and Regional Social Transformation”) the author sets the arguments in a wider context. He explores the extent to which and ways in which universities have become key players in the reimagination of their city regions in a (neoliberal) global context. As well as reflecting on the wider public (and local) role of universities, he also considers how universities use the tools available to them to position themselves effectively as successful businesses within the new world in which they find themselves

    Electrically driven photon emission from individual atomic defects in monolayer WS2.

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    Quantum dot-like single-photon sources in transition metal dichalcogenides (TMDs) exhibit appealing quantum optical properties but lack a well-defined atomic structure and are subject to large spectral variability. Here, we demonstrate electrically stimulated photon emission from individual atomic defects in monolayer WS2 and directly correlate the emission with the local atomic and electronic structure. Radiative transitions are locally excited by sequential inelastic electron tunneling from a metallic tip into selected discrete defect states in the WS2 bandgap. Coupling to the optical far field is mediated by tip plasmons, which transduce the excess energy into a single photon. The applied tip-sample voltage determines the transition energy. Atomically resolved emission maps of individual point defects closely resemble electronic defect orbitals, the final states of the optical transitions. Inelastic charge carrier injection into localized defect states of two-dimensional materials provides a powerful platform for electrically driven, broadly tunable, atomic-scale single-photon sources

    'Appreciating' Drainage Assets in New Zealand Cities: Rain Garden Treatment and Hydraulic Performance

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    Despite recognising rain gardens as a best management practice (BMP) to mitigate urban stormwater runoff, there is a dearth of knowledge about their treatment and infiltration performance. It is believed that organic substrates may enhance some contaminant removal but hinder hydraulic throughput although data showing this is sparse. In order to evaluate the influence of substrate composition on bioinfiltrative system effectiveness, mesocosm-scale (180 L, 0.17 m2) laboratory rain gardens were established. Saturated (constant head) hydraulic conductivity was determined before and after the experimental treatment tests that employed stormwater collected from a neighbouring catchment to investigate contaminant removal efficiencies. The principal contaminant (Zn, Cu, Pb and nutrients) removal efficiencies were investigated for three substrates comprising various proportions of organic topsoil. All total metal concentrations in the effluent were <50% of influent concentrations, with the exception of copper in the topsoil-only system that had negligible reduction due to a high dissolved fraction. The system comprising topsoil only had the lowest saturated hydraulic conductivity of 162 mm/hr and demonstrated the poorest metal (Cu, Zn) removal efficiencies. Interestingly, the system with a combination of sand and topsoil demonstrated most promising metal removal of Cu (53%), Zn (81.2%) and Pb (89.1%) with adequate hydraulic performance (296 mm/hr) required for a stormwater infiltrative system. Overall, metal removal was greater at an effluent pH of 7.38 compared to the 6.24 pH provided in the raw stormwater. Some pH buffering was provided by the calcareous sand in two of the systems, whereas the topsoil-only system lacked such buffering potential to facilitate adequate metal removal. These data highlight the influence of organic topsoil on pH that clearly governs metal speciation and hence removal efficacy in bioinfiltrative systems. Nitrate was net exported from all the systems, especially topsoil contrary to what is believed to be easily removed

    Understanding the scale and nature of outcome change in area-regeneration programmes: evidence from the New Deal for Communities Programme in England

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    The New Deal for Communities (NDC) Programme is one of the most intensive area-based initiatives (ABIs) launched in England. Between 1998 and 2010, 39 NDC Partnerships were charged with improving conditions in relation to six outcomes within deprived neighbourhoods, each accommodating around 9,800 people. Data point to only modest change, much of which reflected improving attitudes towards the area and the environment. There are problems in identifying positive people-based outcomes because relatively few individuals benefit from relevant initiatives. Few positive benefits leak out of NDC areas. Transformational change was always unlikely bearing in mind the limited nature of additional resources, and because only a minority of individuals directly engage with NDC projects. This evidence supports perspectives of ABIs rooted in 'local-managerialism'

    Multidisciplinary health professionals' assessments of risk: how are tools used to reach consensus about risk assessment and management?

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    Author accepted manuscript (Post-Print) made available in accordance with publisher copyright policy.Risk assessment and management are among the most important and complex tasks health professionals undertake in their practice to prevent harm to patients and ensure safe and effective treatment. The aim of this study was to examine how multidisciplinary team members use tools to assess and manage risk, through examination of how tools are used to gather, record and “score” risk information; and how this process impacts on the formulation of risk assessment and management plans, interaction with patients, and consensus with colleagues regarding patient care. Fourteen professionals completed an assessment for a hypothetical client using a risk assessment and management tool, and then discussed their assessment in semi-structured interviews. Professionals were in moderate agreement in their assessments of the client on the tool, and highlighted the complexity of their decision making. Clinical management decisions, such as the amelioration of particular risks, followed assessment of the patient in a consistent way. The tool was an important way to for clinicians to communicate their judgments to others and set plans to direct patient care. Implications for the use of clinical decision making tools and instruments in mental health care, and the need for a focus on multidisciplinary decision making, are highlighted
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