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Research on policy impact has increasingly focused on the practical application of social science research. This paper outlines four roles—substantive expert, information processor, change agent, and scholar—which have helped to increase the potential usefulness of our research while maintaining linkages to the academic community. This paper suggests the general nature of these roles and suggests specific implementation strategies, which need to be pursued as an early and continuing aspect of the research enterprise. Balancing these multiple roles presents several analytical and ethical difficulties, but helps to establish credibility in both the scientific and policymaking communities.  相似文献   
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Methodological advancements in geoarchaeology and spatial and chronological modeling are opening new avenues to interpreting large coastal shell-bearing sites. We document the developmental histories of two such sites around Prince Rupert Harbour, Canada, using systematic percussion coring, intensive radiocarbon dating, and 3D surface mapping with Total Station and LiDAR. We also re-analyze a third site (Boardwalk/GbTo-31) excavated and radiocarbon dated in the 1960s, 1970s, and early 2000s using archival field notes, site maps, and stratigraphic profiles georectified using LiDAR. We map the natural landform beneath the sites and document the degree to which people physically modified landforms through the deposition of massive shell accumulations. We model site development through time and space and use accumulation rates and OxCal modeling to test for intentional deposition events. All three sites demonstrate complex and heterogeneous occupation histories. At each we identify instances of very rapid deposition that effectively terraced and extended parts of the natural landform to create places for constructing houses, though these episodes take place within longer histories of slower quotidian deposition. The anthropogenic modifications to the coastline in this area are the result of these mixed processes associated with long histories of occupation.  相似文献   
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This paper examines the role of accelerator programmes in promoting transnational entrepreneurship. Designed to assist the growth of start-ups by providing seed finance and structured entrepreneurship support, these programmes are now a prominent feature in many entrepreneurial ecosystems around the world. Drawing on in-depth qualitative evidence focused on one particular programme, the paper shows accelerators play an important intermediary or ‘brokerage mechanism’ providing start-ups with enhanced relational connections and networks. Transnational entrepreneurs attracted to these programmes are highly focused on exploiting these networks whilst maintaining multiple levels of embeddedness in various contexts to maximize the opportunities afforded by accelerators. While many governments are attempting to replicate accelerators programmes within the public sector, the paper concludes that such attempts may prove problematic within weaker entrepreneurial ecosystems.  相似文献   
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The paper presents an algorithm for computing the parameters of an ellipse that fits, in a least-squares sense, the surveyed remains of Roman amphitheatre arena walls. The algorithm is validated using ideal data and the near complete remains of the amphitheatre at Sarmizegetusa in Romania. The technique is then applied to the partial remains of the amphitheatre at the Guildhall in the City of London, in the UK, which cover only the Eastern end of the monument. The underlying mathematical model and method of solution is presented. The method was developed with a view to determining firstly whether or not an ellipse is a feasible model for the actual constructed curve geometry, and secondly, where the Western end of the Guildhall amphitheatre might be located. One single ellipse was found to fit the Guildhall remains, with measurement residuals at the level of 30 mm in the eastings and 26 mm in the northings. The ellipse had a semi-major axis of 28.345 m and a semi-minor axis of 22.775 m. The issues of alternative geometries and the practicalities of their use in construction are considered.  相似文献   
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