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31.
Grasslands pose a particular problem for archaeological survey involving artifact assessment, as no material is plowed up to the surface. Although finds in molehills are often the only source of information available on sites with such low visibility, an archaeology of molehills has thus far been largely disregarded. Yet, by applying a low-cost and time-efficient methodology, both the potential and the pitfalls of molehill archaeology come to the forefront. At the medieval harbor site of Monnikerede, it was possible to assess material culture and to locate certain structural elements. However, when artifact densities were compared with the underlying geophysical anomalies, a more complex relationship appeared at the level of individual features.  相似文献   
32.
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   
33.
Radon (Rn) is a potentially toxic gas in soil which may affect human health. Assessing Rn levels in soil gas usually requires enormous efforts in terms of time and costs, since the sampling protocol is very complex. In most cases, the variable under study is sparsely sampled over the domain and this could affect the reliability of the spatial predictions. For this reason, it is useful to incorporate, into the estimation procedure, some auxiliary variables, correlated with the in soil gas Rn concentrations (primary variable) and more densely available over the domain. On the basis of this latter aspect, it is even better if the covariates are derived from a geographical information system (GIS). In this article, the Rn sampling protocol used during a measurement campaign planned over a risk area is described and the process of deriving GIS covariates considered as secondary information for predicting the primary variable is clarified. Then, multivariate modeling and prediction of the Rn concentrations over the domain of interest are discussed and a comparative study regarding the performance of the prediction procedures is presented. Rn prone areas are also analyzed with respect to urban and school density. All these aspects can clearly support decisions on environmental and human safeguard.  相似文献   
34.
The seismic response of a continuous 4-span bridge designed according to the current Canadian seismic provisions is investigated using Incremental Dynamic Analysis (IDA). Different earthquake types, including shallow crustal events, interface Cascadia subduction, and deep inslab subduction are considered. The median collapse capacities calculated using different record selection methods including Conditional Mean Spectrum (CMS)-based, Uniform Hazard Spectrum (UHS)-based, and epsilon-based methods are compared. The use of the epsilon-based method generally resulted in the highest collapse capacity predictions, but the CMS-based method was less sensitive to the number of records considered in the IDA.  相似文献   
35.
GeoDa : An Introduction to Spatial Data Analysis   总被引:49,自引:0,他引:49  
This article presents an overview of GeoDa™, a free software program intended to serve as a user-friendly and graphical introduction to spatial analysis for non-geographic information systems (GIS) specialists. It includes functionality ranging from simple mapping to exploratory data analysis, the visualization of global and local spatial autocorrelation, and spatial regression. A key feature of GeoDa is an interactive environment that combines maps with statistical graphics, using the technology of dynamically linked windows. A brief review of the software design is given, as well as some illustrative examples that highlight distinctive features of the program in applications dealing with public health, economic development, real estate analysis, and criminology.  相似文献   
36.
Small angle neutron scattering and neutron phase analysis techniques have been for the first time jointly employed to extract microscopic parameters of ceramic samples prepared under controlled conditions, in an attempt to establish a protocol for deriving information on the firing process. Data have also been collected on two series of early medieval samples from the Italian regions of Cuma and Miseno. The variation of the microscopic features observed on these samples could mirror some technological evolution in the period spanning from the 6th to the 12th century AD.  相似文献   
37.
宋德金 《史学集刊》2004,3(4):82-87
忠孝是中国古代伦理的重要内容 ,中国传统文化的组成部分。契丹、女真早期本无忠孝观念。辽金建立后 ,随着社会的发展 ,儒学的传播 ,统治者的倡导 ,民族的融合等 ,忠孝观念逐渐形成和发展起来。忠孝在辽金及后来元人那里 ,超越了民族、地区和国别的畛域 ,人们对外族、邻国、敌国乃至前朝的忠臣孝子同样表现出尊重和崇敬。 1 0 - 1 3世纪 ,忠孝已成为汉、契丹、女真、蒙古等各民族一致认同的伦理道德观念和行为规范 ,从而体现了中国传统文化的历史继承性和强大凝聚力。  相似文献   
38.
"吧国公堂"档案之《公案簿》述略   总被引:4,自引:1,他引:3  
<公案簿>是现存吧国公堂(巴达维亚华人评议会)档案中的核心部分,所涵盖的时间范围大约为150年(1787-1940年)左右.<公案簿>的内容主要有两个方面一是对吧国公堂有关华人的各类案件的会审记录;二是对有关吧城华人社区重要事件和重大决议的记录.对涵盖这一时期最为原始的记事录的内容及案例加以考察和分析,一方面可以洞察一个处在多种变革时期具有代表性的华人社区的社会生活及其行政管理的内幕,另一方面也可以从中了解各个历史阶段荷印殖民政策的变化及其对当地华人社会的影响.  相似文献   
39.
A high correlation between chronometric determinations based on aspartic acid racemization ratios and radioactive dating methods is described from samples of cave bear (Ursus deningeri and Ursus spelaeus) dentine. For samples from a very restrictive environment, as deep cave bear sites are (in view of their highly stable geochemical and thermal history), an age calculation algorithm was obtained. It has been found that there is a very close relationship between collagen preservation, from total aspartic acid in the > 3500 D fraction, and the amino acid racemization.  相似文献   
40.
The characterization of a ceremonial bronze axe is described. The axe is assigned to the Santamarian culture of north‐west Argentina, c. 1000–1470 ad, and was selected to increase presently limited knowledge of prehistoric metallurgy in the Andean region of Argentina. The characterization methods used were electron probe microanalysis, gamma radiography, X‐ray diffraction, optical metallography and microhardness testing. The axe was well cast in a bivalve mould, with the only defects in the area of an ancient fracture. The analysis showed that it is made from a tin bronze with a, probably, accidental addition of lead. Arsenic was found as a surface contamination, probably deriving from arsenic in the water of the stream in which the axe was found. The axe shows that Santamarian craftsmen had the skill to decorate the axe in an artistic style with a strong local accent while providing a functional, annealed and cold‐worked cutting edge.  相似文献   
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