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101.
目前对文物保护的研究主要以试验为主,本研究试图用数值方法分析文物展柜的动力学特性,以解决试验分析方法所导致的缺陷。为此,对固定和浮放两种不同边界条件的文物展柜进行地震作用和简谐激励下的动力响应分析,给出了展柜展台面处的加速度动力放大系数(简称放大系数)上限值。以某博物馆展柜为原型,按1∶1/0.39进行缩尺振动试验,得出两种边界条件下展柜展台面处的放大系数。对试验展柜建立有限元模型,通过与试验对比,验证模型及分析方法的正确性。然后,建立展柜模型的有限元模型,对5种尺寸的展柜进行了动力响应分析,并考虑激励幅值、激励频率等对放大系数的影响。分析结果有助于指导文物的防震保护工作。  相似文献   
102.
Oral cleft (OC) is a common congenital anomaly in humans, which occurs in approximately one per 700 live births. However, cleft skulls are found relatively seldom in archaeological specimens, especially for the bc period. Mortality of infants with OC was apparently high because of breastfeeding difficulties and culturally sanctioned rejection of them in the past. This paper presents one of the most ancient cases of OC in Eurasia. The finding comes from the Middle Bronze Age pastoralists' cemetery in Altai, Russia. The skeletal remains have been radiocarbon dated to 1883–1665 cal bc . Cranial and dental measurements, computed tomography and radiography have been used to examine this malformation. The facial sculpting reconstruction has been performed to visualise the ante mortem appearance of the cleft face. Besides, δ13C and δ15N isotope analysis was used for a comparative study of the diet of the cleft individual. It has been established that a young man from Altai was affected by complete bilateral cleft lip and alveolus, which is a very rare form of typical OC. This defect is associated with dental anomalies such as hypodontia, microdontia, and ectopia as well as with dysmorphology of the facial complex outside the cleft area, including mild hypertelorism, hypoplasia of nasal bones and antheroposterior maxillary deficiency. Furthermore, aplasia of the frontal sinuses and the sacral spina bifida occulta have been observed. These findings are consistent with clinical data indicating strong correlation between development of a major defect and multiple minor anomalies. The results of the study also suggest that there was tolerant attitude towards the facial deformities among the ancient Altai pastoralists. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
103.
Late Postclassic period (a.d. 1350–1525) Tarascan economic activities often included higher degrees of political involvement and territorial control compared with other ancient Mesoamerican societies. Here I examine Tarascan obsidian economies through an analysis of lithic production and consumption patterns from structures excavated on and near the Great Platform at the imperial capital of Tzintzuntzan. Four spatially distinct patterns are evident. Great Platform residents used high-quality obsidian blades as ceremonial items or burial offerings and scrapers for craft production. Lower elite residents of Structure F, outside the Great Platform, produced their own blade tools and consumed a higher percentage of green obsidian than residents of the Great Platform. Excavations at Yacata 3 recovered bifacial arrowheads and obsidian bloodletters associated with disturbed offerings. The spatial distributions of lapidary preforms and highly polished fragments combined with accounts from the Relación de Michoacán (a.d. 1541) suggest that lower elites produced obsidian jewelry near the Great Platform.  相似文献   
104.
The Tequila Valleys, in Jalisco, Mexico, are well-known in archaeology for an early complex society known as the Teuchitlán tradition (350 b.c.a.d. 450/500), but later developments have received little attention. Here I report on the first systematic, full-coverage survey of the Tequila region north of the Tequila volcano. I explore the ways in which the societies that occupied this territory experienced sociopolitical change diachronically by investigating settlement scale, integration, complexity, and boundedness. Through the use of these core features, I analyze how each changed in varying ways, resulting in patterns that do not conform to static societal categories. Interestingly, there is no evidence that a large polity controlled the entire region at any point in the sequence. Results indicate a dynamic sociopolitical landscape that did not develop along any predetermined pathway.  相似文献   
105.
Initiated in 2004, the RICardo project focuses on bilateral trade data of all the world's countries from the early nineteenth century to the eve of the Second World War. The project includes the construction of a database and the creation of a website. It is a pioneering work in the field of historical trade statistics that aims at providing easy-to-access research material to the scientific community and at attracting a wider public to the history of trade relationships. The article emphasizes the originality of the project and sums up its various aspects by reviewing previous trade databases, clarifying the main features of historical trade statistics, and describing the construction and use of the RICardo website.  相似文献   
106.
Is a third passage to the past possible, beyond Elton's and Fogel's two roads of narrative history and scientific/quantitative history? One that would combine narrative history's focus on the event, on individuals and their actions, at a particular time and place, to scientific/quantitative history's emphasis on explicit behavioral models based on social-science theories? That is the question this article addresses. It illustrates a computer-assisted methodology for the study of narrative—quantitative narrative analysis (QNA)—that does just that. Based on the 5 Ws + H of narrative—Who, What, When, Where, Why, and How—QNA quantifies events without losing the event itself, without losing people behind numbers, diachronic time behind synchronic statistical coefficients. When used in conjunction with dynamic and interactive data visualization tools (and new natural language processing tools), QNA may provide a third unforeseen road to the past.  相似文献   
107.
Roman plasters sampled from different houses at the archaeological site of Herculaneum, Italy, (2010–12) were studied by means of petrography, thermal analysis and X‐ray fluorescence. Herculaneum plasters are composed by preparatory layers (arriccio) with a thickness of several centimetres and are based on a calcitic binder and volcanic scoriae as aggregates, covered by a thin final layer characterized by a low granulometry. Most of the sampled plasters can be placed into two groups based on the aggregate composition and classified as marmorino or intonachino. However, a similar aggregate composition did not induce superimposable thermal behaviour, thus suggesting that the samples underwent different ageing/weathering processes, with a consequent change of the ratio among the components.  相似文献   
108.
Dental modification was widely practiced in sub‐Saharan Africa as a form of cultural expression, and during the era of the transatlantic slave trade, it was regularly identified in enslaved Africans who were transported to the Americas. Here, we report three new cases of African types of dental modification from the Caribbean island of Saint Martin that were recently encountered during construction activities in the Zoutsteeg area of Philipsburg, the capital of the Dutch half of the island. The artifacts associated with the burials indicate that they date to the late 17th century, prior to the foundation of the town of Philipsburg in 1735. The dental evidence further suggests that the three individuals were born in Africa, as opposed to the Americas. This could be confirmed by tooth enamel strontium isotope measurements which yielded values that are inconsistent with an origin in the Caribbean but consistent with an origin in Africa. Unfortunately, neither the dental patterns nor the strontium isotope values allow us to determine their specific origins in Africa. However, both the methods used to modify the teeth and the isotope ratios suggest that the ‘Zoutsteeg Three’ originated in different parts of Africa. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
109.
110.
The chemical composition and petrographic features of 51 samples of fine pottery selected from the archaeological site of Syracuse have been established by means of optical microscopy and X‐ray fluorescence spectrometry, with the aim of creating a reference group for the ceramics produced in this important Greek colony during the Hellenistic–Roman period. This reference group is constrained by the analysis of six kiln wasters and of raw materials outcropping in the studied area. Among the studied findings, the main part is assignable imputably to local production, while some specimens probably come from Greece and other colonies (Messina and Gela). The Syracuse fine pottery is characterized by inclusions formed mainly by quartz and micaceous and fossiliferous groundmass. The used pastes were more or less purified through the removal of the sandy‐to‐coarse silty granulometric fraction. The multivariate statistical analysis of chemical data permits the identification of production at Syracuse on the basis of comparison with the kiln wasters and the Plio‐Pleistocene clays.  相似文献   
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