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11.
上世纪以来,邢台市各级文物部门通过发掘、征集等方式入藏了一批宋金时期的陶瓷枕。这些陶瓷枕造型有椭圆形、如意形、银锭形、扇形等,釉彩有素白釉、白釉黑彩、绿釉、三彩釉等,装饰技法有印花、划花、贴塑等,具有较高的历史和艺术价值。 相似文献
12.
Monitoring is deemed crucial for the incentivization of a decentralized organization, but its function relies on information transparency between the central authority and the delegated individuals. We test this hypothesis by considering changes in the fiscal behavior of Chinese county governments following an exogenous fiscal reform in 2004/2005 that removed information obstacles between provinces and counties. Employing data on 590 Chinese counties from 2000 to 2009, we find that counties in the reform provinces adopt a more proactive fiscal policy after the reform, suggesting that they become more incentivized in the political competition for economic growth. Such effects are stronger in counties with fewer competing peers and counties with either high or low ranks in the records of economic growth among peers. The increase in counties' productive spending leads to higher economic growth in later years. 相似文献
13.
西安城墙东门箭楼砖坯墙体风化因素研究报告 总被引:2,自引:2,他引:0
论述了西安城墙东门箭楼的文化背景,实地考察了风化外状,并对风化外状进行了分类测试。通过对砖坯墙体材料进行化学全分析、X-射线衍射分析、吸水率测定(含他和系数)、冻融实验、泛霜实验、环境污染与水文气象监测资料的分析,研究了东门箭楼砖坯墙体不同风化外状的风化因素,同时对现代修缮用砖的理化性能及质量进行了评估。结果表明,温度的交替变化、水的冻结与融化使得砖坯裂解成碎块;干湿引起可溶盐的结晶与潮解以及自然界中的雨水、地面水或地下水、污染气体等通过溶解、水化、水解、碳酸化、氧化等方式,使得砖坯墙体表面酥碱粉化。同时说明研究适用于古建筑修缮使用的抗风化仿古青砖是当务之急。 相似文献
14.
Gravity models with fixed coefficients have been used to explain the trade flows between countries different in income levels and separated by long distances. It is unrealistic to assume that these models can hold with the same parameters across very heterogeneous countries. This paper proposes and estimates an international trade model with variable coefficients constructed by combining Pöy-hönen's and Linnemann's gravity-based trade models via the expansion method. 相似文献
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16.
We develop a new conceptual approach to locating inspection stations for hazardous vehicles, prevention, and compare it to the previous, punitive, philosophy of the flow-capturing location model. We implement this preventive protection philosophy with a new mixed integer program that maximizes hazard avoidance by locating a number of inspection stations to detect and remove hazardous vehicles as early in their trips as possible. We test the model's performance and analyze the spatial characteristics of solutions simulating several potential applications. Our computations demonstrate that a relaxed integer-linear program is overly demanding computationally and that a simple greedy heuristic lacks robustness. We suggest further approaches to developing more powerful and efficient solution methods. 相似文献
17.
Investigating Human Migration and Horse‐Trading in Yelang (夜郎) Through Strontium Isotope Analysis of Skeletons from Zhougshui Sites,South‐West China (1300 bc – ad 25) 下载免费PDF全文
Yelang (夜郎), a mysterious state located in the south‐western area of early China and dating from the Bronze Age to the Early Iron Age (1300 bc – ad 25), is a cultural interactive junction between the Yunnan–Guizhou Plateau and the Yangtze River Basin. The Zhongshui Basin in Weining County, Guizhou Province, was one of the important distribution areas of the Yelang civilization. This area, which includes sites at Jigongshan (鸡公山; 1300 – 800 bc ), Hongyingpan (红营盘; 700 – 400 bc ) and Yinzitan (银子坛; 400 bc – ad 25), has provided a very integrated chronology, spanning from the Bronze Age to the Early Iron Age in the eastern Yunnan – western Guizhou area. To investigate human migration and horse‐trading at these Yelang sites, we conducted a strontium isotopic analysis on the teeth enamel of humans and horses unearthed from these three sites. The results indicated the following: (1) people at the earlier sites (Jigongshan and Hongyingpan) were all indigenous, whereas in the Yinzitan cemetery, there was a more immigrant population, and all the people who were buried in an upper limb flexed supine position were non‐local; and (2) most of the horses found at the Jigongshan and Yinzitan sites show different provenances, probably related to the famous Dian (滇) and Zuo (筰) horses recorded in historical documents, providing more clues for further study on horse‐trading in South‐West China during the Bronze Age and the Early Iron Age. 相似文献
18.
An Approach to the Diagnosis of Craniofacial Fibrous Dysplasia from the 2500‐Year‐Old Remains of a Skull from Ancient China 下载免费PDF全文
K. L. Cheng H. Shao D. Zhao B. T. Sun J. Yu Z. C. Sun M. C. Li L. Guo H. Zhu Q. C. Zhang Y. H. Huang 《Archaeometry》2018,60(1):171-182
A human skull, buried about 2500 years ago in a Bronze Age cemetery at Jinggouzi, a site of an important ethnic group in ancient China, appeared to have characteristics of fibrous dysplasia. The CT images indicated a reduction in bone density and relatively homogeneous lesions. More features were revealed using CT reconstruction techniques. Lesions seen in low‐magnification images using a 3D deep‐field microscope had an irregular honeycomb‐like structure. At higher magnification, the trabeculae morphology and the gaps between the trabeculae were irregular and varied in size and shape. Paraffin‐embedded specimens stained with HE showed trabeculae with tortuous irregular arrangements varying in shape and width. The irregular trabeculae of woven bone has been described as having fibrous dysplasia. Molecular analysis of the GNAS gene indicated no mutation. This provides a non‐invasive approach for us to make more comprehensive diagnoses and to assist research into ancient human diseases. 相似文献
19.
ABSTRACTThe emerging problem of left-behind children has attracted mounting academic and policy attention. Prior studies primarily cast light on left-behind children’s education, health, and behavior, while their subjective well-being is much less understood yet. Based on a nationally representative sample of rural children aged 10–15 in 2014, we examine the impacts of different types of parental migration on children’s subjective well-being and how these affects vary between boys and girls. The results show that parental migration is a double-edged sword: children from both-parent migrant families report compromised life satisfaction and relationship quality compared with those in integral families, and mother-only migration significantly lowers children’s subjective health. On the flip side, father-only migration enhances children’s aspiration for attaining college, an encouraging effect that is even stronger than that of parental education and family income. These effects are heterogeneous by children’s gender: boys seem to be more susceptible to the disruptive effects of both-parent migration; mother-only migration effectively promotes girls’ educational aspiration while father-only migration promotes boys’. This study portrays a comprehensive image of left-behind children. Relaxation of hukou restriction, equal access to education, and revitalization of rural economies are imperative to improve the well-being of left-behind children.Abbreviations: LBC: Left-behing children; SWB: subjective well-being 相似文献
20.
正It is just the dawn,but the sheepfolds have already begun to move restlessly.Sunlight makes its way in.Tashi Tsedan and Redan open the sheepfolds one after another.Flocks of sheep suddenly gush out like an influx of water from an opened gate.These two herdsmen from Jirong Village in Drik Town of Gampa County are fulfilling their duty grazing these flocks of Gampa sheep,a well-known breed of Tibetan sheep. 相似文献