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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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A poor understanding of the physical environment often hinders management of marine artefacts. A study was conducted of an early-18th-century shipwreck to test whether the wreckage could have settled through ∼3.5 m of substrate. Results indicate that the wreck could have settled via episodic scour processes driven by storms and tidal inlet migration. A numerical model, modified to include characteristics of the underlying geology, predicts continued scour under moderate waves. Scour processes appear to have been interrupted by an erosion-resistant underlying layer, so that the wreck now remains exposed, subject to degradation. A generalized approach to predict burial or exposure of other shallow-water artefacts is developed.
© 2006 The Authors  相似文献   
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The use of a pottery vessel leaves markers on the ceramic wall that can inform archaeologists how the vessel functioned in the past. At present, archaeologists have little information for understanding how use-alteration reflects the complex nature of ceramic function and socioeconomic status. I conducted a 2-year ethnoarchaeological research project among the Gamo people of southwestern Ethiopia, who continue to produce and use pottery on a daily basis. This research indicates that interior surface attrition occurs primarily on pottery vessels used in wealthy households because of fermentation processes from high-status foods. Thus, the Gamo example suggests that there is a relationship between ceramic use-alteration and household socioeconomic status.  相似文献   
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Domestic ovicaprine specimens, some attributed specifically to Ovis aries L., have been recovered at two Mesolithic sites in the western Languedoc region of France, and two sites in southeastern France. The sites are typical late Mesolithic occupations, firmly dated between 7300 BP and 8000 BP, and stratigraphically precede the appearance of other domestic animals, cultivated plants, pottery, and the establishment of settled villages in their regions. They seem to represent early steps in the adoption of animal husbandry by hunter-gatherer societies in the western Mediterranean. Evidence from the Aude valley sites is presented for the gradual development of animal herding over a period of 1000 years or more, which spans the Mesolithic-Neolithic boundary. The evidence suggests that indigenous Mesolithic societies may have played a formative role in the development of settled farming communities in this area, and that the availability of domestic species may not have led rapidly to major changes in settlement, economy and society.  相似文献   
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