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1.
Ancient mortars played a crucial role in the construction of historical architectures due to their physical and chemical compatibility with traditional building materials such as stones and bricks. Therefore, the analysis and optimization of the ancient mortar formula are significant in the restoration and preservation of historical sites. In this work, 20 mortar samples selected from five ancient stone pagodas in Zhejiang Province, China, were analyzed. The results showed that mud, lime-soil mortar, lime-sand mortar, and lime-gypsum mortar were used as binders in these pagodas. The Ca(OH)2/aggregate ratio ranging from 0.3 to 2.7 was usually used to prepare lime mortar. Protein and polysaccharide were also found in some samples.  相似文献   
2.
The paper investigates the patterns of technology and knowledge of the regions. The first aim of the paper is to determine cluster templates at the national level. The second aim of the paper is to investigate the technology and knowledge composition of the regional highpoint clusters. The paper identifies patterns of industrial linkages to define cluster templates and regional highpoints. The second part uncovers regional distributions of technology and knowledge. The data comes from Turkey’s 2012 input–output table. The location quotients use industrial employment statistics from the Turkish Statistical Institute. The technological and knowledge intensity classification follows Eurostat. The findings reveal 10 cluster templates in Turkey. Spatial distribution of the highpoint clusters reveals that most regions contain highpoint clusters with low technology and low knowledge-intensive sectors. The results reveal that highpoint clusters in Turkey’s regions contain industries whose technologies do not demand high skills, knowledge and sophistication. Limited existence of high-tech industries and low knowledge intensity in Turkey’s industry composition is a limiting factor for transition to high value-added manufacturing. Special emphasis should be directed towards constructing regional advantage, given the current levels of technology and knowledge intensity.  相似文献   
3.
朱定秀 《安徽史学》2007,4(3):13-16
国家恐怖主义是由政府实施的恐怖主义,法西斯主义则是国家恐怖主义发展到登峰造极的产物.国家恐怖主义具有制度化、公开性和社会化的特点,并具有独裁政治,庞大的镇压机器,镇压性的特务机关,非人道的人身迫害,非战争状态下对大量人口的集体收监、屠杀或迫使其流亡,针对社会知名人士的暴力行为等构成要素.  相似文献   
4.
This study investigates temporal changes in dietary practices in the Caribbean archipelago during the Ceramic Age (400 BC–AD 1500), through analyses of dental wear and pathology. Some previous studies in the region have suggested that diet and subsistence practices changed over time due to increasing sociopolitical complexity, climate change, or adaptation to island environments rich in marine resources. Both horticultural/agricultural intensification and increased marine focus of the diet over time have been posited, based among other things on faunal and botanical remains, and early ethnohistorical accounts. Local and micro‐regional stable isotope studies of temporal dietary variation have found few indications for change over time, and large regional isotope studies are still lacking. Dentitions from sites throughout the region dating to the Early Ceramic Age (400 BC–AD 600/800) and the Late Ceramic Age (AD 600/800–1500) were analysed in order to assess temporal differences. Intra‐individual rates of wear were calculated using the difference in degree of wear between the adjacent molars and the two groups were compared with principal axis analysis. Caries, antemortem tooth loss, abscesses and dental calculus were recorded per individual and per tooth/socket, and population caries and antemortem tooth loss rates were assessed and compared by age group, tooth class and sex. Comparisons between the two occupation periods revealed significant differences in the rate of dental wear and pathology, indicating a shift in dietary practices over time, coinciding with known social changes. The increase in pathology rates suggests a rise in the consumption of cariogenic foods or preparation techniques that increase cariogenicity. The decrease in rate of wear over time indicates a reduction in abrasivity of the diet. Together these data suggest that there was a growing focus on refined, cariogenic foods, likely horticultural/agricultural produce. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
5.
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   
6.
Archaeobotanical survey has sampled a series of late Neolithic to early Bronze Age settlements in the upper Ying valley (part of the central plain of China) and provided useful data for understanding prehistoric arable ecology and farming during a period of increasing local social complexity. A combination of the modelling functions offered by Geographic Information Systems (GIS) and the data reduction possibilities offered by Principal Component Analysis (PCA) allow us to explore possible relationships between local arable ecology, crop-processing strategies and the natural environment. The results should be treated cautiously given the size of the analytical sample but suggest that differences in the natural environment around each site may explain varying patterns of wild food collection, while social and cultural factors may better explain variation in farming practice and crop-processing at different sites.  相似文献   
7.
明末统治阶级的横征暴敛及连年自然灾害,促使农民大起义暴发。李自成农民义军攻入北京,推翻明王朝后,紧接着吴三桂引清军入关。随着全国社会主要矛盾的急剧变化,农民起义军由原之反对明王朝统治转为联合明宗室所建南明政权共同抗清斗争。  相似文献   
8.
Abstract

In view of the compendium of field evidence and supporting analysis work indicating the possible damaging effects of vertical earthquake ground motion, this paper addresses the problem of code-type vertical force calculation. In light of recent engineering seismology studies of the relationship between vertical and horizontal peak ground acceleration, the inadequacy of the 2/3-rule depicted by codes is highlighted. A simple piece-wise linear relationship is proposed and shown to represent existing strong-motion measurements adequately. Bilinear and inelastic spectra are derived and studied. It is demonstrated that net tensile forces and displacements may ensue, thus eroding the shear resistance of RC columns. A simple procedure is outlined whereby modal analysis may be employed to estimate conservatively vertical earthquake forces on buildings. Finally, areas of further exploration and refinement are identified.  相似文献   
9.
黑河流域居民生活质量研究   总被引:1,自引:0,他引:1  
彭浩  曾刚  徐中民 《人文地理》2009,24(4):66-71
以《Calvert-Henderson生活质量指标》一书为理论指导构建了生活质量评价指标体系,通过开展生活质量问卷调查及查找相关统计资料,运用主成分分析法确定指标的权重,研究了我国西北地区第二大内陆河流域-黑河流域城乡居民2004年的生活质量。具体的评价结果是:黑河流域城镇居民生活质量明显高于农村;黑河流域城市居民生活质量表现出中游高于上游和下游;黑河流域农村居民生活质量以乡镇为单位计算差异显著;黑河流域农村居民生活质量中游略好于上游、下游;影响黑河流域城乡居民生活质量的主要因素是收入、教育和住房。  相似文献   
10.
辽宁省城市中心性研究与城市发展   总被引:1,自引:0,他引:1  
以辽宁省地级及以上城市为研究对象,在建立评价指标体系基础上,基于区位商法和主成分分析法,对城市中心性进行了测度和研究。通过对过程数据和结果数据的进一步分析,发现辽宁省当前城市发展在区域经济空间结构、社会经济体制、第三产业、经济外向度等方面存在的问题,并提出了相关的政策建议。  相似文献   
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