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81.
Difficulties in evaluating accurate equivalent doses for Late Quaternary sediments from the south coasts of Greece arose in the course of SAR measurements. Large scatter among apparent equivalent doses perplexed the evaluation of accurate mean estimates in circumstances where very large doses were involved. Besides, dose recovery experiments revealed that when intersection of the natural signal occurs onto the saturating segment of the growth curve, a distinct relationship between De and growth curve shape occurs. At very low slope angles, SAR tends to overestimate the recovered dose. The mechanism which controls the spread in equivalent dose estimation is investigated.  相似文献   
82.
It has been suggested that the standardised growth curve (SGC) method can be used to de-terminate De accurately and reduce the measurement time. However, different opinions regarding the applicability of the SGC method exist. In this paper, we report the construction of quartz OSL SGC for 35 aeolian samples from different parts of the Horqin dunefield in northeastern China, and then test their applicability for De determination. Our results suggest that: 1) up to a regeneration dose of 80 Gy, the SGC of the Horqin dunefield can be fitted using the exponential plus linear equation, with the r2 value of 0.97, and all the regeneration dose points closely stick to the fitting line, implying that all samples share a very similar dose-response curve; 2) for samples with Des ranging from 1 to 50 Gy, the ratios of SAR De to SGC De fall within the range of 0.9–1.1, and the average ratio of SAR De to SGC De is 1.01±0.01, close to unity. Therefore, the construction of SGC is correct, and the SGC is an effective procedure for accurate De determination for samples from the study area.  相似文献   
83.
Due to the construction of a new North-South subway in Cologne, Roman time harbour sediments were exposed and were sampled for luminescence dating. A very good independent age control was given by the precise knowledge of the chronology of Roman activity and by radiocarbon ages of charcoal samples. Hence, different methodological approaches within luminescence dating were applied for Holocene heterogeneously bleached fluvial samples and were compared to the known ages. For one sample, optically stimulated luminescence (OSL) dating was applied to coarse-grained quartz using a single aliquot regenerative-dose (SAR) protocol. After De-measurements, different statistical approaches were tested (i.e. arithmetic mean, median, minimum age model, finite mixture model, leading edge method and the Fuchs and Lang approach). It is demonstrated that the Fuchs and Lang approach along with the leading edge method yielded the best matching OSL ages with respect to the known ages.  相似文献   
84.
The present study focuses on investigations carried out in the Late Vistulian succession of the Warta River deposits (central Poland) in which a horizon of subfossil trees was excavated. Prelim-inary conclusions on time record and past environmental conditions of a forest existence determined from radiocarbon dating, pollen analyses and geological evidence appear promising with view of tree-ring chronologies.  相似文献   
85.
Plant and particularly non-wood forest products have played an important role in the evolution of human cultures all over the world, as source of food but also of raw substances fulfilling material, spiritual, and medicinal requirements. Plant exudates and particularly dammar resins (Dipterocarpaceae family) were widely used in the past in Asia notably as waterproofing and caulking materials. This study focuses on the GC–MS chemical characterisation of freshly collected dammars and establishes new molecular parameters enabling discrimination between dammars and other types of plant resin, whatever their botanical origin. Such analyses provide clues for a precise identification (taxonomy, occurrence of other material in addition to the resin, alteration state) of unknown resinous material discovered in archaeological contexts. The value of our approach is illustrated by the taxonomic characterisation of two samples collected in jars from the Brunei wreck and a Chinese junk lost more than 40 km off the Sultanate of Brunei during the end of the fifteenth century or the early beginning of the sixteenth century.  相似文献   
86.
In late nineteenth- and early twentieth-century America, the consumption of American-made goods was seen as an expression of one’s patriotism and loyalty to the nation. According to a number of historical archaeological case studies, racialized groups, such as African Americans and Chinese Americans, used consumption as a way of gaining access to the full benefits of American citizenship typically reserved for individuals deemed “white” by law. The material culture of Mexican immigrants living in early twentieth-century Los Angeles tells a slightly different tale. Despite being ascribed a legal whiteness, archaeological and documentary data suggest that Mexican immigrants expressed ambivalence toward their consumption of American goods and outright rejected the notion that exerting such buying power would lead to a broader acceptance in Anglo American society.  相似文献   
87.
Michael Schiffer’s theoretical and methodological contributions to archaeology are substantial. For the last two decades, Schiffer has become increasingly interested in the history of electrical technology, including portable radios, electric automobiles, eighteenth-century electrostatic technology, and, most recently, nineteenth-century electric light and power systems. Schiffer has long held a behavioral view, which focuses analytical attention on interactions between humans and material things, including complex technological systems (CTSs). For Schiffer, two key aspects of the evolution of CTSs are stimulated variation, defined as an increase in invention resulting from changing selective conditions, and cascading, defined as sequential spurts of invention that occur through the recognition of emergent performance problems in a CTS. To attain maximum usefulness, these concepts should be placed in a modern evolutionary framework that correctly identifies, and does not oversell, the role played by cultural selection. Research on individual and social learning provides the critical link between Schiffer’s stimulated variation and cascade models and the diffusion of CTSs.  相似文献   
88.
This study examines how the archaeology of historic Ireland has been interpreted. Two approaches to the history and archaeology of Ireland are identified. The first, the timeless past, has its roots in a neo-Lamarckian view of the past. This perspective was particularly developed in the work of geographer and ethnographer, Estyn Evans. The second view, associated in particular with a nationalist approach to Ireland’s past, looked to the west of the country where it was believed the culture had been preserved largely unchanged and in its purest form. The continuing impact of these frameworks upon the interpretation of rural settlement in the period 1200–1700 is examined. It is argued that historians and archaeologists alike have underestimated the quality of buildings.  相似文献   
89.
History was an important notion in constructing an industrial capitalist society in the nineteenth century. This article deals with the manifest use of history at the Stockholm Exhibition of 1897. At this exhibition, history was ubiquitous and was most fully expressed in the model of medieval and Renaissance Stockholm called “Old Stockholm.” The history of nineteenth- and twentieth-century exhibitions in general has been thoroughly studied in the field of humanities. However, the specific use of history and space has not attracted much interest. This analysis of the model of Old Stockholm is of the first archaeological study of remains of the great exhibitions ever to have been done. Even though the “Old Stockholm” pavilion was exceedingly popular in the summer of 1897, only very scarce documentation has survived. An archaeological excavation of parts of the temporary historical models, such as the “Hospital of the Holy Spirit,” showed convincing evidence of the hegemonic position which the use of history enjoyed at the exhibition and in the nineteenth century.  相似文献   
90.
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