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31.
The regulation of scientific and archaeological diving is complex but it is essential that underwater archaeologists are familiar with the requirements placed on them by legal systems. This paper outlines the history and development of current legal systems in four jurisdictions: the UK, USA, EU and Australia. This historical and legal approach informs key discussions facing maritime archaeologists; reference is made to training requirements, safety records and the question of who should be allowed to participate and who should be excluded from archaeological diving.  相似文献   
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The analysis and preservation of organic materials preserved within wetland environments represents one of the most costly parts of any post-excavation strategy. This paper outlines the application of high-resolution terrestrial laser scanning to one class of preserved material, worked archaeological wood. Scanning allowed the recording of the artefacts in three dimensions and the identification of features such as toolmarks. Features can be measured and volumetrically modelled within the digital environment, which may not always be possible for these often fragile materials using conventional techniques. Repeat scanning of the artefacts provided an opportunity to use comparative analysis software to investigate changes in the morphology of artefacts under contrasting conditions of short-term storage. The results suggest that immersion in water results in the least deterioration, whereas both freezing and air-drying caused distortion and degradation. This paper demonstrates that laser scanning provides a viable alternative post-excavation method for the recording, analysis and long-term ‘virtual archiving’ of organic archaeological materials, which may be more cost-effective in some instances than other methods of preservation.  相似文献   
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A central but often unasked question in political and sociological scholarship concerns the conditions that precipitate cooperation on large-scale transnational energy projects, especially among “developing” and “emerging” economies. Using the example of two multi-billion dollar pipeline systems – the Trans-ASEAN Natural Gas Pipeline (TAGP) Network in Southeast Asia and Baku-Tbilisi-Ceyhan (BTC) Pipeline in the Caspian Sea – this article explores the factors that result in successfully completed projects, and those that lead to conflict and contention. After drawing from extensive research interviews and field research, the article approaches politics and technology through the lens of science and technology studies. It relies on the interdisciplinary concepts of “relevant social group” and “technological frame” to identify coalitions of actors associated with each pipeline project. The paper then investigates the interests and motivations behind these groups to illuminate the challenges facing the TAGP and those that accelerated the completion of the BTC. The paper concludes by offering some thoughts on the diverse elements needed to incentivise cross-border energy infrastructure, and what these may mean for energy and public policy scholars.  相似文献   
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A geophysical survey at the pyramid complex of Senwosret III at Dahshur sought to determine the suitability of magnetometry and electromagnetic induction (EMI, or conductivity) for mapping the area where several ancient boat-burials were found in the 1890s. At least one boat reported at the time of excavation remains unaccounted for. Tests demonstrated that magnetometry does detect subsurface structures of stone, fired brick, and unfired brick under current site conditions. Data indicated areas of geological activity as well as unexcavated archaeological remains, though no definitive traces of boat burials. No excavation was undertaken but another survey season is planned.
© 2009 The Authors  相似文献   
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This paper seeks to examine how federal financial support of academic scientists shapes their collaborative behavior. More specifically, it investigates two questions: (i) are there threshold sizes of federal grants that have effects on collaboration? and (ii) do the threshold sizes differ by discipline? To test and model these questions, this paper uses data collected in a 2004–2005 survey by the Research Valuing Mapping Project (a project based at Georgia Tech and led by Barry Bozeman) of 2,086 academically based research scientists and engineers. The analysis in this paper reaffirms the positive relationship between federal funding and collaboration seen in previous works, but the findings suggest that there is in fact a threshold effect—as the positive relationship has a diminishing influence. The findings of this paper are more limited with respect to how academic disciplines’ threshold levels differ. The results indicate a difference in the threshold levels between disciplines for three of the eight models.  相似文献   
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