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Telepresence-enabled exploration of deep sea environments has developed over the past 30 years, providing access to archaeologists, scientists, and the general public to sites otherwise inaccessible due to depth. Pioneered through the inception of the JASON Project in the late 1980 s, telepresence missions have expanded to two dedicated ships of exploration, NOAA Ship Okeanos Explorer and exploration vessel Nautilus, and has been implemented on a series of opportunistic missions on other vessels. This paper chronicles the history of the use of telepresence for the exploration of shipwrecks in deep water as well as how this capability has allowed the public to engage with such missions. Broadening the scope of who can explore the deep sea, telepresence has also expanded what is observed and documented in the deep, which speaks to humanity’s use of the maritime world and an archaeology of discard through our material disposed of into the deep sea.  相似文献   
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The restoration of paintings on elements in cultural heritage buildings (fundamentally, churches) involves two structural problems: capturing the geometry of the construction element and its development. In many cases, the geometries are regular (e.g., cylinders, spheres, elliptical domes). However, there are cases in which the elements cannot be adapted to any known geometry, much less one that can be mathematically developed. The development of surfaces becomes essential for the restoration of paintings over “flat elements” (over which work is performed on the ground) that are subsequently transferred to the real surface (ceilings). The mathematical transformations that allow regular geometries to be developed are widely known (cartographic projections). However, when the geometry is irregular, there is no development. This study presents a new methodology based on differential rectification and its application for the development of oculi in the Los Santos Juanes Church (Valencia), whose geometry is completely irregular both in shape and as a result of construction defects (and damage caused by fire). The present study focuses on the restoration of paintings damaged by fire.  相似文献   
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The taphonomic analysis of avian remains from Sarakenos Cave reveals that, contrary to previous suggestions, many bird bones excavated there represent food remains of the Eagle Owls rather than humans. The conclusion is based on the presence of traces of digestion, beak and claw punctures, and indirect evidence that includes relative preservation of particular elements, species composition, the lack of cut marks, and the absence of numerous traces of burning. Specimens with medullary bone and traces of digestion indicate that the owls killed breeding females in spring. Since it is unlikely that owls shared the cave with humans at the same time, it supports the notion based on archeological evidence that human groups did not inhabit it permanently.  相似文献   
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Accurate simulation of multiphase flow in fractured porous media remains a challenge. An important problem is the representation of the discontinuous or near discontinuous behaviour of saturation in real geological formations. In the classical continuum approach, a refined mesh is required at the interface between fracture and porous media to capture the steep gradients in saturation and saturation‐dependent transport properties. This dramatically increases the computational load when large numbers of fractures are present in the numerical model. A discontinuous finite element method is reported here to model flow in fractured porous media. The governing multiphase porous media flow equations are solved in the adaptive mesh computational fluid dynamics code IC‐FERST on unstructured meshes. The method is based on a mixed control volume – discontinuous finite element formulation. This is combined with the PN+1DG‐PNDG element pair, which has discontinuous (order N+1) representation for velocity and discontinuous (order N) representation for pressure. A number of test cases are used to evaluate the method's ability to model fracture flow. The first is used to verify the performance of the element pair on structured and unstructured meshes of different resolution. Multiphase flow is then modelled in a range of idealised and simple fracture patterns. Solutions with sharp saturation fronts and computational economy in terms of mesh size are illustrated.  相似文献   
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