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61.
The studies on the finishing technique of the stone monuments in Persepolis (Iran) are part of the archaeological project jointly launched in 2008 by Iran and Italy, named ‘From Palace to Town’. The first experimental results, obtained on a very limited number of samples, revealed that the Achaemenid builders and sculptors used a white pigment, a kind of bone white, calcium fluorapatite, obtained by burning animal bones, to hide the dark grey colour of the stone. In order to verify these unexpected results, a new campaign was implemented to analyse a much larger number of samples. XRF spectrometry, a non‐destructive technique, was used and the experimental results were further elaborated by PCA. The presence of a white superficial layer was confirmed, and the use of fluorapatite was confirmed as well, but only on monuments attributed to the Xerxes period or later, while in the earlier monuments the white layer was obtained using gypsum.  相似文献   
62.
Quiet urban areas are places with low noise levels that can help people to support physical and mental wellness. This paper has two objectives: to identify quiet urban areas in Montreal and to check for the presence of environmental inequities in access to such areas for vulnerable groups (children, older people, low‐income individuals, and visible minorities). Using a GIS‐based methodology, 2,282 quiet urban areas were identified in Montreal. The results of a mixed effects logistic regression model analysis showed that there are no major inequities in access to quiet urban areas for the population groups studied. The analysis did, however, revealed substantial spatial disparities in terms of the distribution of quiet urban areas across the boroughs and municipalities examined.  相似文献   
63.
The Ford Nuclear Reactor operated from 1957 to 2003 on the University of Michigan's North Campus in Ann Arbor, Michigan. Over its 45‐year lifespan, the facility played a key role in archaeometric research, fostering early methodological studies using INAA and supporting archaeological materials science investigations of lithics, ceramics, metals and bone. One small part of the FNR's abundant legacy was the initiation of trace‐element studies of Oaxacan ceramics, which are now beginning to shed light on early exchange interactions and the origin of the Monte Albán state in the Valley of Oaxaca, Mexico, between 500 bce and 200 ce .  相似文献   
64.
We provide a compositional perspective on the origins of the Cahuachi cult in Nasca, south coast of Peru. Instrumental Neutron Activation Analysis of ceramics from the Formative site of La Puntilla demonstrate that a small group of pottery known as Nasca 1 blackwares are compositionally consistent with Early Nasca polychromes originating at Cahuachi. These data suggest that the patterns of pilgrimage and group ceremonies exhibited at Cahuachi during Early Nasca began at least in the proto-Nasca phase of Nasca 1 during the Formative. We use these data to further document the Paracas to Nasca transition, a complex and dynamic period in south coastal prehistory.  相似文献   
65.
Having been adopted by legislatures in over a dozen states, postsecondary merit aid programs are largely concentrated in the southeastern United States. The observed clustering pattern seems to support previous evidence that policies spread between proximate states, a phenomenon referred to by political scientists as policy diffusion. Often, however, policy diffusion is not complete, and one or more states in a region fail to adopt. By interviewing policymakers throughout the southeastern United States—including actors in the three states in the region without merit aid—the study addresses the following question: Why do diffusion pressures lead to adoption in some states but not in others? Studying state “hold‐outs” promises not only to uncover the reasons for failed legislation in specific state contexts but also to better our understanding of the limits of diffusion theory.  相似文献   
66.
The paper presents an algorithm for computing the parameters of an ellipse that fits, in a least-squares sense, the surveyed remains of Roman amphitheatre arena walls. The algorithm is validated using ideal data and the near complete remains of the amphitheatre at Sarmizegetusa in Romania. The technique is then applied to the partial remains of the amphitheatre at the Guildhall in the City of London, in the UK, which cover only the Eastern end of the monument. The underlying mathematical model and method of solution is presented. The method was developed with a view to determining firstly whether or not an ellipse is a feasible model for the actual constructed curve geometry, and secondly, where the Western end of the Guildhall amphitheatre might be located. One single ellipse was found to fit the Guildhall remains, with measurement residuals at the level of 30 mm in the eastings and 26 mm in the northings. The ellipse had a semi-major axis of 28.345 m and a semi-minor axis of 22.775 m. The issues of alternative geometries and the practicalities of their use in construction are considered.  相似文献   
67.
Studies of the African members of the family Bovidae have demonstrated the feasibility of using linear discriminant analysis to predict paleoenvironment based on measurements from postcranial skeletal elements. The use of discriminant analysis depends upon adherence to certain assumptions about the data set. In certain cases, these assumptions are violated, thus reducing the confidence of the results. The research presented here introduces the use of the non-parametric recursive partitioning method as a test of the linear discriminant method for predicting habitat from a collection of modern Bovid astragali from Southeast Asia. This study also provides a critique of the previous African studies. The results indicate that a combination of the parametric and non-parametric methods provides the highest prediction accuracy for Southeast Asian Bovids, though the independent methods do test favorably; thus providing an additional tool for archaeologists and paleoanthropologists in this region.  相似文献   
68.
闵小芳 《攀登》2007,26(2):25-27
培养造就“有文化、懂技术、会经营”的新型农牧民,是建设社会主义新农村新牧区最本质、最核心的内容,也是全面落实科学发展观的必然要求。本文就青海省在新农村新牧区建设中培养新型农牧民的有关问题进行了分析,并提出了相应的建议和对策。  相似文献   
69.
以中国社会科学引文索引(CSSCI)为操作平台,以核心作者群的被引论著为样本,对样本篇数、篇次、作者、机构、地域分布、主题分布、年代分布等因素进行了引文分析和量化的描述,并从文献的角度对大陆华侨华人研究现状进行评估。结果表明:大陆华侨华人研究1993—2002年是高峰期,形成了以福建、北京、广东为主的核心作者群,高等院校仍是华侨华人研究的主要机构,研究主题以经济、社会、历史为主,学术论文的利用率不高,高水平的研究成果不多。华侨华人研究在学术界的整体影响力不大,某些不够科学和规范的引证态度和方法亟需改进。  相似文献   
70.
宁明花山岩画区危岩体稳定研究   总被引:1,自引:1,他引:0  
花山岩画区的危岩体的存在严重危及古岩画的保存和游客的安全,使得旅游业遭到重创。为了对区内危岩体状态做出评价,并为其后期治理工程提供依据,通过对岩画区的环境地质条件和病害成因的调查,结合危岩体的形态和结构特征,分析得出了区内危岩体崩塌破坏的三种模式为倾倒式崩塌、错断式崩塌和拉裂式崩塌,并提出了不同破坏模式的力学模型。应用极限平衡法对不同破坏模式的危岩体进行了稳定性计算分析,得出区内危岩体大部分处于欠稳定状态,须进行治理。最后提出了危岩体的防治原则与措施。  相似文献   
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