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61.
Ruth M.K. Plets Justin K. Dix Jon R. Adams Jonathan M. Bull Timothy J. Henstock Martin Gutowski Angus I. Best 《Journal of archaeological science》2009
The remains of Henry V's flagship, the Grace Dieu, currently lie buried within the inter-tidal sediments of the River Hamble (S. England). Previous archaeological investigations have been hindered by difficult excavation conditions resulting in a poor understanding of the dimensions, shape and degradation state of the hull's deeper structure. This study therefore aimed to image, characterize and reconstruct the buried remains of this vessel using a high-resolution 3D acoustic sub-bottom Chirp system with RTK-GPS positioning capability. The accurate navigation and high-resolution data that were acquired enabled the construction of a full 3D image of the site that not only identified the remains of the wooden hull, but also features buried within it. In addition, the degradation state of these buried wooden remains were investigated by calculating reflection coefficients while a hypothetical larger reconstruction of the Grace Dieu's hull was achieved, through the use of the ShipShape ship design software package. 相似文献
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Many analysts are concerned about territories subject to state failure becoming safe havens for terrorists. In this article, I apply this logic to maritime piracy syndicates and their ship hijacking operations, and argue that a focus on the geographies of state failure can help us explain why pirates' behavior varies between failed and weak states. Analysis of a dataset of hijacking incidents suggests that state failure is associated with less sophisticated attacks, while state weakness encourages more sophisticated attacks. Through case studies of the process by which pirates carry out their attacks in East Africa and Southeast Asia, I argue that it is the differences in political and economic landscapes that influence how pirates embed their operations across territory, and thus how they carry out their operations. Notably, because they do not have to worry about enforcement, pirates in failed states can engage in time-intensive kidnappings for ransom, while only weak states provide the markets and transportation infrastructure necessary for operations where ships and cargo are seized and sold for profit. These findings suggest that weak states might actually be more problematic for international security in some respects than failed states. 相似文献
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