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11.
李海荣 《南方文物》2011,(4):125-143
珠江三角洲地区的沙丘遗址,因为堆积结构比较松散而使发掘中一些露出的沙层不稳定,很容易造成不同层位遗存的混乱。但是,这些沙丘遗址的文化层是客观存在的,本来在气候十分湿润、地表植被非常茂密的环境下也是比较稳定的,而后人发掘或人工取沙挖坑是造成层位混乱的主要原因。所以,稳固在发掘中露出来的沙层,是沙丘遗址发掘的关键。只要发掘中露出的沙层稳固住了,再运用一些层位判别的方法,沙丘遗址的文化层是可以划分清楚的。从陶器的类型学研究、系列的测年数据以及与蚝岗遗址的对比来看,都可以证明咸头岭遗址所划分的地层是可信的。  相似文献   
12.
Remains of anadromous Pacific salmon and trout (genus Oncorhynchus) are common in archaeological sites from California to Alaska; however, morphological similarity generally precludes species identification, limiting the range of questions that salmonid remains can address in relation to past human use and ongoing efforts in conservation biology. We developed a relatively simple, rapid, and non-destructive way to classify salmon and trout vertebrae from archaeological contexts to species using length, height and the ratio of length to height. Modern reference material was obtained from all seven anadromous Oncorhynchus species native to the west coast of North America. A minimum of ten adult Chinook (Oncorhynchus tshawytscha), chum (Oncorhynchus keta), coho (Oncorhynchus kisutch), pink (Oncorhynchus gorbuscha), and sockeye salmon (Oncorhynchus nerka) and cutthroat (Oncorhynchus clarki clarki) and steelhead trout (Oncorhynchus mykiss) were skeletonized and vertebra length and height were measured. Morphometric analyses compared species classification success based on Linear Discriminant Analysis (LDA), Classification and Regression Trees (CART), and randomForest, with CART performing the best. Classification analyses used all seven species individually, but because of considerable overlap among several species we also conducted analyses on four species groupings. We assigned Chinook salmon and cutthroat to their own groups based on their dissimilarities from each other and the other species. The remaining species were divided into two group complexes (a) chum, coho, and steelhead; and (b) pink and sockeye. When we grouped species according to similar morphology, CART overall success rates increased, ranging from 92 to 100%. Individual species with the highest successful classification rates using CART were Chinook salmon and cutthroat, from 92 to 100%, respectively. We applied our classification to an assemblage of ancient (1000–3000 year old) salmonid vertebrae from the Swiftwater Rockshelters excavations on the upper Wenatchee River in Washington State, U.S.A.  相似文献   
13.
New Zealand has some of the most active areas of rhyolitic volcanism in the world and this has produced numerous obsidian sources in the northern half of the North Island. In total archaeologists have recognized 27 named locations from which obsidian can be obtained scattered across 4 geological source regions. Shortly after colonization in the late 13th century AD Polynesian settlers began transporting this material some thousands of kilometers throughout the country and across the sea in small quantities to distant neighbors in the Kermadecs and Chatham islands. Although considerable research has been conducted on obsidian sourcing in New Zealand the complexity of geochemical source discrimination and the lack of a practical method of non-destructive geochemical analysis has hindered progress. We present the results of our use of PXRF to provide geochemical data on New Zealand obsidian sources and to compare the use of discriminant analysis and classification tree analysis to discriminate among sources and attribute archaeological samples to sources. Our research suggests that classification tree analysis is superior to discriminant analysis in sourcing studies. A large case study using an important settlement phase site (S11/20) from the Auckland region demonstrates the utility of the methods and the results support a model of high degrees of mobility and interaction during the early settlement of New Zealand.  相似文献   
14.
A quarter of a millennium ago, Samuel Tissot (1728–1797), a Swiss physician who had achieved a substantial European reputation, authored a monograph entitled Traité de l’épilepsie. The book was translated into several European languages and appeared in various editions over the following 70 years, although an English-language version was never published. In his Traité, Tissot provided a thorough account and critical analysis of the previous relevant literature concerning epilepsy, added data from his own experience in practice, and raised issues, some of which remain important today. The appearance of the book was propitious, occurring during the period of the European Enlightenment, when medicine was increasingly divesting itself of ancient modes of thinking and veneration for the opinions of great names from the remote past. At least in Western Europe, the Traité de l’épilepsie became an intellectual launching pad for the considerable expansion in knowledge of epilepsy that occurred over the century or longer that followed its publication.  相似文献   
15.
“十一五”期间,我国提出100处重要大遗址的保护工作。本工作基于大遗址保护数字化保护的具体需要,将大遗址进行分类,并将其与地理信息相关的数据进行编码,建立我国大遗址的地理数据编码标准,以期在大遗址保护中,对大遗址数据库建设和监测起到基础性支撑作用。  相似文献   
16.
In this article, site response analyses for 124 sites collected in Korea were performed to evaluate earthquake ground motions in regions of shallow bedrock in Korea. Based on the results, a new two-parameter site classification system was developed for use in regions of shallow bedrock. The system incorporates depth to bedrock and mean VS of soil above bedrock as parameters for site classification instead of VS30. Soil sites were divided into seven site classes and the corresponding site coefficients were proposed for each site category. Some verification work demonstrates the superiority of the proposed system over the current seismic codes.  相似文献   
17.
18.
Despite longstanding anthropological concerns with the origins of intensive delayed-return subsistence economies and the timing of the development of increasingly complex political systems on the Northwest Coast, the use and production of slate knives—one of the most archaeologically visible tools used to process seasonally available salmon—has received little attention in the archaeological literature. This can be attributed, in part, to the persistence of artifact typologies that have failed to generate behavioral implications for variability in slate artifact assemblages. In this article, I use data derived from ethnographic, experimental, and actualistic research to develop an approach to the classification of slate artifacts expected of knife-production activities. Emphasis is placed on framing slate knife production as a temporally emergent and situated activity, but also as an operational sequence that can be modeled due to regularity in the decisions and motions expected of tool makers producing functionally specific tools. Using slate assemblages recovered during the partial excavation of seven Late and Contact period Coast Salish houses in southern British Columbia, I then evaluate and demonstrate the utility of this approach by considering variability in household labor contributions to salmon fishing.  相似文献   
19.
This paper is aimed at determining the effects of the soil characterization on the seismic input to use for seismic assessment. Three different soil profiles have been assembled to represent the stratigraphies found through a proper experimental investigation, carefully described, and alternative seismic site response analyses have been performed. The surface spectra obtained from the seismic site response analysis (SRA) are very different from each other, thus evidencing the importance of carefully describing soil stratigraphy. Furthermore, the comparison among the surface records found for different return periods has shown a limited sensitivity of the SRA to the seismic intensity.  相似文献   
20.
We classify sites based on their predominant period computed using average horizontal-to-vertical (H/V) response spectral ratios and examine the impact of this classification scheme on empirical ground-motion models. One advantage of this classification is that deep geological profiles and high shear-wave velocities are mapped to the resonance frequency of the site. We apply this classification scheme to the database of Fukushima et al. [2003] Fukushima, Y., Berge-Thierry, C., Volant, P., Griot-Pommera, D. A. and Cotton, F. 2003. Attenuation relation for west Eurasia determined with recent near-fault records from California, Japan and Turkey. Journal of Earthquake Engineering, 7(3): 126.  [Google Scholar], for which stations were originally classified as simply rock or soil. The calculation of average H/V response spectral ratios permits the majority of sites in the database to be unambiguously classified. Soft soil conditions are clearly apparent using this technique. Ground-motion prediction equations are then computed using this alternative classification scheme. The aleatoric variability of these equations (measured by their standard deviations) is slightly lower than those derived using only soil and rock classes. However, perhaps more importantly, predicted response spectra are radically different to those predicted using the soil/rock classification. In addition, since the H/V response spectral ratios were used to classify stations the predicted spectra for different sites show clear separation. Thus, site classification using the predominant period appears to be partially mapped into the site coefficients of the ground-motion model.  相似文献   
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