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991.
Tim Foecke Li Ma Matthew A. Russell David L. Conlin Larry E. Murphy 《Journal of archaeological science》2010
Scientists from the National Institute of Standards and Technology (NIST) worked in a collaborative partnership with archaeologists from the National Park Service's (NPS) Submerged Resources Center (SRC) to develop a finite element model (FEM) of the battleship USS Arizona. An FEM is a computer-based engineering model that calculates theoretical stresses, propagation of force, and shape changes to a structure under loads using thousands or even millions of individual elements whose individual responses are well understood. NIST researchers created an FEM of an 80 ft. (25 m) midships section of the Arizona site to analyze archaeological site formation processes on the sunken battleship, in particular to determine the current condition of the wreck and predict its future strength and structural integrity as it continues to corrode. The NIST's FEM study is one aspect of a larger project under the direction of the NPS, the USS Arizona Preservation Project, whose goal is to determine the nature and rate of corrosion affecting USS Arizona, and to model its long-term structural deterioration. The FEM incorporates findings from other key components of the USS Arizona Preservation Project, such as steel hull corrosion rates, structural surveys of the vessel, sediment compaction studies, and analysis of the concretion that covers the ship's hull, into a single tool that is being used to predict how the wreck will degrade in the future. 相似文献
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Michael Lobb Kristina Krawiec Andy J. Howard Benjamin R. Gearey Henry P. Chapman 《Journal of archaeological science》2010
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
993.
David Romand 《Revue de synthèse / Centre international de synthèse》2010,131(1):35-51
During the 19th century, the question of the relation between the soul and the body was deeply renewed by German psychological studies. The new elaborated conception of the relationship between the psychical and the physical coincides with the appearance of a cognitivist paradigm, in which mental phenomena are considered as entities that may be individualised, isolated, and then correlated with the activity of specific neural substrates. German psychologists were confronted with the problem of the correlation between psychical life and the nervous system (localisation of mental phenomena and nature of this correlative relationship), and propose an extensive analysis on the neural conditions and the emergence of psychical processes. 相似文献
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Frédérique Valentin Hallie R. Buckley Estelle Herrscher Rebecca Kinaston Stuart Bedford Matthew Spriggs Stuart Hawkins Ken Neal 《Journal of archaeological science》2010
The subsistence strategies of the Lapita populations (3100–2800 BP), the first colonisers of the pristine environments of the islands of Eastern Melanesia and Western Polynesia, have been a matter of ongoing debate for decades. Opinions have ranged between the two extremes of Lapita colonisers being either characterised as highly mobile foragers to fully horticultural communities. To further address the question, this paper presents stable carbon and nitrogen isotopic data obtained from analyses of human and animal collagen samples from the site of Teouma (Efate, Vanuatu) dated to between c. 3000–2500 BP. The isotopic signatures obtained from 28 samples (23 human and 5 animal), interpreted in combination with isotopic information from several coastal and insular environments, suggest a diet primarily made up of terrestrially derived animal protein with lesser contributions from vegetable produce and inshore marine species. Comparisons linking the isotopic data gleaned from the Teouma individuals and Lapita subsistence patterns reconstructed through archaeozoological and archaeobotanical remains support the hypothesis of a mixed economy, that included terrestrial foraging, inshore marine exploitation and a low level of food production for at least some of the earliest Lapita colonists in Vanuatu. 相似文献
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