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141.
Recent investigations of botanical material from archaeological sites have provided seeds and plant remains exhibiting a crystalline or semi-crystalline appearance. X-ray diffraction and partial chemical analysis have revealed that the particular plant materials had been replaced by calcium phosphate. Using systematic sampling and retrieval techniques a significant body of data has been accumulated. Most mineralized botanical evidence has been recovered from faecal deposits, in particular cess pits and garderobes, and has provided an important source of information about aspects of diet of past populations.  相似文献   
142.
The problems of interpretation of many overlapping species lists of fossil assemblages are discussed using the example of insect faunas from a late medieval farm site in southern Iceland. Numerical techniques were employed, principally those available within the CLUSTAN package, and it was concluded that a considerable refinement in interpretation was achieved. Such quantitative procedures are suitable for groups other than fossil insects but their employment cannot be regarded as a substitute for, rather than an adjunct to, a sound ecological approach.  相似文献   
143.
The technique of growth-line analysis is used to examine seasonal growth patterns in modern specimens of the edible cockle, Cerastoderma edule L. The modern control work provides a basis for the interpretation of seasonal collection in archaeological cockles, and is applied to shells from the Mesolithic site of Morton, Fife. The seasonal use of the site is shown to be clearly related to site function.  相似文献   
144.
Black-on-red ware was widely used throughout the Eastern Mediterranean between about the 11th and 8th centuries BC. Its origins have been much discussed: its ubiquitous appearance throughout the region could be a result of either several manufacturing regions or a single place of manufacture associated with considerable trading in the ware.In the present study, neutron activation analysis has been carried out for 15 chemical elements in 58 specimens of black-on-red ware from Cyprus (11), Syria (26) and Palestine (21). The analytical results clearly separate the ware into three major groups, corresponding to origins in Palestine, Syria and Cyprus. The hypothesis of a single source of the ware is therefore not tenable. All 14 of the Syrian finds of the single-handled neck ridge juglet are closely grouped with the Cyprus samples, indicating extensive trade in this vessel from Cyprus to Syria. The Palestine samples clearly separate into two sub-groups. Arguments are presented suggesting that this indicates the ware from the two sub-groups was made at different times. The Cyprus group provides tentative evidence of several sites of manufacture on the island.  相似文献   
145.
赖建波  潘竟虎 《人文地理》2019,34(3):108-117
“腾讯迁徙”大数据基于位置服务,实时、动态、完整、系统地描述了用户日常出行活动的轨迹。通过采集“腾讯迁徙”数据平台中2018年春运期间中国346个地级及以上城市之间的逐日人口流动数据,分“节前、节中、节后”3个时间段,利用复杂网络分析方法,从人口流动的集散层级、集散体系分层集聚特征、人口流动空间格局、网络空间特征等角度分析各时间段城市间的人口流动特征与空间格局。结果表明,腾讯迁徙大数据直观地揭示了春运期间中国城市间人口流动空间格局,3个时段人口的净流入均呈现十字形骨架支撑的菱形分布,人流集散中心主要集中在京津冀、长三角、珠三角和成渝4大城市群,与城市等级有较强的一致性。人口流动集散体系呈明显的分层集聚,城市行政级别的高低与人口流动影响力存在一定的正相关关系,大部分城市人口流动处于“相对平衡”状态。人口流动网络呈现东密西疏的分布特征和东部并联、西部串联的网络关联特征。人口流动网络局部具有较明显的“社区”结构特征,聚为3个大区级、5个跨区域级和1个地区级社区。  相似文献   
146.
In the recent literature on the cultural politics of naming, toponyms and street names are increasingly read within the wider social–historical context upon which naming is contingent. In this perspective, naming is often seen as an act of power and a way to inscribe an ideological discourse into the landscape. In this article, we analyze the street names currently inscribed in the historical center of the Italian city of Milan, Italy as a reflection of its long and contested social and political history. Fragments of all the different toponymic regimes and hegemonic discourses that took over one after the other over time have remained inscribed in Milan’s street network, originating a complex tapestry in which different pasts revive and conflicting ideologies co-exist. In this context, we examine the role Geographical Information Science (GIScience) methods and technologies play in quantifying, revealing, and visualizing the spatial patterns of downtown Milan’s toponymic texture at the urban scale and at the scale of the six historical neighborhoods.  相似文献   
147.
The quantitative analysis of glass, ceramics and related silicate systems by means of energy dispersive X-ray fluorescence spectrometry is considered and problems arising from the selective absorption of X-rays in multi-element specimens are discussed. A computer programme written in FORTRAN and based upon a “semi-fundamental parameters” approach to the correction of matrix effects in glass and chemically similar materials is fully described. Model data are provided to enable the programme to be run and tested. An “empirical coefficients” computer programme for the quantitative analysis of silicate systems is outlined and the limitations of this type of programme are pointed out. The importance of adequate sample preparation prior to X-ray spectrometric analysis is stressed.  相似文献   
148.
青花瓷器产地判别研究   总被引:2,自引:0,他引:2  
本项研究以江西省景德镇、云南省玉溪、建水、福建省平和的青花瓷器为主,结合香港清代碗窑以及德国、日本、泰国的现代青花瓷器,用能量色散X射线荧光(EDXRF)分析方法,在无损的情况下对其元素含量进行分析,得到了Ti、Mn、Fe、Co、Ni、Cu、Zn、Ga、Pb、Rb、Sr、Y、Zr13个元素的含量结果。用主成分分析方法对数据进行处理,利用第1主成分、第2主成分、第3主成分在三维座标系中绘制散点图,所得类群关系与已知情况完全相符。研究结果表明本文的研究方法可用于青花瓷器的产地判别。  相似文献   
149.
Isotopic analysis of skeletons excavated during the 1950s has confirmed that they are the remains of shipwreck victims: slaves on board the Portuguese slaving brig Pacquet Real when it sank on 18 May 1818. Twenty-five slaves drowned and the remaining 133 became Prize Negroes at the Cape. The isotopic signatures are consistent with values expected for people living in an African village eating a terrestrially based diet. Analyses of different skeletal elements, i.e., teeth, long bone, and rib, are shown to be a valuable tool in tracing change or consistency in diet during a person's life, because different skeletal elements form at different stages of life and, subsequently, remodel at different rates. A comparison of isotope ratios from different skeletal elements indicates a change in diet in all these individuals, probably coincident with their enslavement. Variation between individuals in the isotopic composition of diets eaten early in life is sufficiently large to deduce heterogeneous origins for the group.  相似文献   
150.
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