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The general trends of the inelastic behaviour of plan-asymmetric structures have been studied. Systems with structural elements in both orthogonal directions and bi-axial eccentricity were subjected to bi-directional excitation. Test examples include idealised single-storey and multi-storey models, and a three-storey building, for which test results are available. The response in terms of displacements was determined by nonlinear dynamic analyses. The main findings, limited to fairly regular and simple investigated buildings, are: (a) The amplification of displacements determined by elastic dynamic analysis can be used as a rough, and in the majority of cases conservative estimate in the inelastic range, (b) Any favourable torsional effect on the stiff side, which may arise from elastic analysis, may disappear in the inelastic range. These findings can be utilised in the approximate pushover-based seismic analysis of asymmetric buildings, e.g. in the N2 method. It is proposed that the results obtained by pushover analysis of a 3D structural model be combined with the results of a linear dynamic (spectral) analysis. The former results control the target displacements and the distribution of deformations along the height of the building, whereas the latter results define the torsional amplifications. The proposed approach is partly illustrated and evaluated by test examples. 相似文献
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Camilla Terenzi Cinzia Casieri Anna Candida Felici Mario Piacentini Margherita Vendittelli Francesco De Luca 《Journal of archaeological science》2010
A combination of energy dispersive X-ray fluorescence (ED-XRF) and 2D proton nuclear magnetic resonance (1H NMR) relaxometry was employed for the characterization of two groups of similar ceramic fragments from the high-medieval production of the Phlegrean area (Miseno and Cuma, Southern Italy). Both methods are based on the use of non-destructive and portable instruments. This approach allows to correlate complementary microstructural features of ceramics, both dependent and independent of the firing technique. 相似文献
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K. Godde 《International Journal of Osteoarchaeology》2010,20(4):388-395
Scholars have identified a hiatus in the archaeological record of Lower Nubia that spans approximately 1000 years. This interval may represent a desertion of Lower Nubia by its inhabitants. Evidence of occupation did not reappear in the area until the Meroitic time period. However, the identity of the returning people has been the subject of speculation. In order to determine who the Meroites of Lower Nubia were, 20 cranial non‐metric traits were observed on six Nubian groups, representing five time periods. Two groups date to time periods immediately before (Kerma) and immediately after (X‐Group) the Meroitic period. Three additional Nubian groups (two Christian samples from different sites and Sesebi, a contemporary sample) were utilised as outgroups to elucidate a clearer picture of the relationship among the six samples. Mahalanobis D2 with a tetrachoric matrix was employed for calculating biological distances among the groups. Principal coordinates analysis produced two clusters of Nubians, where the Meroitics clustered with other Nubian groups. Specific distance scores indicate the Meroites were biologically similar to individuals from the time periods prior to and after their arrival in Lower Nubia. The Meroites therefore appear to be a Nubian group returning to Lower Nubia after its desertion. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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《International Journal of Osteoarchaeology》2017,27(6):1048-1058
Ceremonies involving intentional burial of animals with humans are acknowledged to bear religious, social and political connotations, and we explored both the ritual activity and the social trajectory of these activities. To date, these ceremonies have rarely been examined within the context of nearby daily activities. We studied faunal remains associated with intramural burials in comparison with contemporaneous daily life in the midsecond millennium bc at Tel Megiddo, as well as comparison with concomitant extramural burials and locations of public feasts. Our study highlights the human interaction with animals that are not often treated as bearing social meaning or having interrelationships with human, the livestock animals. We demonstrate that livestock animals in the second millennium bc had a significant social role as well as economic value. The choice of animals consumed and sacrificed in these rituals is strongly related to the animal's symbolic potency and is based on the desired social message that the population aims to convey. Finally, the form of luxury food that is found in the Megiddo funerary rituals supports the hypothesis regarding the intramural burials' role in creating and enhancing social family bonds. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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This study assesses the displacement of coalbed methane by CO2 migration along a fault into the coal seam in the Yaojie coalfield. Coal and gas samples were collected continuously at various distances in NO.2 coal seam from F19 fault. Vitrinite reflectance, maceral, and pore distributions and proximate analysis of fourteen coal samples were performed. Gas components, concentrations, carbon isotopes of 28 gas samples were determined. We examined the coal–gas trace characteristics of coalbed methane displaced away from the fault by CO2 injection after geological ages. From east to west, away from the F19 fault, the CO2 concentration decreased, whereas the CH4 concentration increased gradually. The δ13C values for CO2 varied between ?9.94‰ and 1.12‰, suggesting a metamorphic origin. A wider range of values (from ?9.94‰ to 20‰) was associated with the mixing of microbial carbon dioxide, isotopic fractionation during CO2 migration through the microporous structures of coals, and/or carbon isotope fractionation during gas–water exchange and dissolution of CO2. Away from the F19 fault, the volumes of micropores, mesopores and macropores decrease gradually. The Dubinin–Radushkevich (DR) micropore volume decreased from 0.0059 to 0.0037 cm3 g‐1, and the mesopore and macropore volumes decreased from 0.066 to 0.026 cm3 g‐1. The CO2 injection can mobilize aromatic hydrocarbons and mineral matter from coal matrix, resulting in the decrease in the absorption peak intensity for coal samples after supercritical CO2 treatment, which indicates that chemical reactions occur between coal and CO2, not only physical adsorption. 相似文献
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《中国文物科学研究》2014,(4):90-94
山东定陶王墓地(王陵)M2汉墓为目前我国已发掘规模最大的“黄肠题凑”汉墓,201 3年被公布第七批全国重点文物保护单位.20 14年,中国文化遗产研究院组织编制的“山东定陶王墓地(王陵)M2汉墓保护工程方案”获国家文物局审批通过.本文概述了“山东定陶王墓地(王陵)M2汉墓保护工程”的项目背景、项目设计、任务分解及各个子项目工作的开展情况. 相似文献
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本文从《张家山汉简》所出汉初法律条文着手,对汉初户赋和户刍的性质进行了细致分析,指出二者是一种特殊性质的户税,具有税率很轻的特点。由此,进一步探讨了汉代户税的演变过程,认为文景与武帝时期社会状况的变化是导致汉代户税不断加重又突然消失的重要原因。 相似文献
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Christopher Reid 《Parliamentary History》2020,39(2):239-254
For much of the 18th century, letter writing remained an important means of communicating news about proceedings at Westminster. Members of leading parliamentary families such as the Hardwickes were prolific letter writers and their correspondence has long been valued as a source for the period before the regular reporting of debates became established in the newspaper press. This article focuses on reporting by letter in the correspondence of the 2nd earl of Hardwicke and his circle. It reconstructs Hardwicke's network of informants and considers how the nature of their connection with the earl affected the way they conceived of their role as reporters. With reference to the epistolary conventions of the time, it asks how the circumstances in which letters were composed and read may have shaped the style and content of the reports. Finally, the article examines the impact made on the epistolary tradition by the emergence of newspaper reporting in the later 18th century and assesses the extent to which this development led letter writers to adjust their methods and goals. 相似文献
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