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51.
陈尚胜 《中国边疆史地研究》2015,25(2):4-20,180
东亚地区传统国际秩序应称"封贡体系"较为周全。封贡关系的要义在于"事大"与"字小"。从中国明清王朝与朝鲜、琉球、越南等属国关系看,朝贡制度也是双边贸易、文化交流、边疆管控以及司法合作的基本机制,而在属国遭遇国家安全危机时,作为"上国"的明清王朝也积极进行政治外交和军事上的援救行动。不过,朝贡制度旨在建立"上国"与"属国"之间的主从关系,各个"属国"之间并没有围绕"上国"而形成合作联盟。因此,它在近代难以抗衡运用条约体系的西方列强以及日本在东亚地区的扩张。 相似文献
52.
陈晓伟 《中国边疆史地研究》2015,25(2):93-101,182
辽、金、元三朝皇帝每年皆例行驻夏活动,习称"夏捺钵",并在国家政治生活中占有举足轻重的地位,其中以炭山避暑最为引人注目。作者从四库本宋元文献中所见"阿延川"、"上京"两名入手,认为"阿延川"本作"爱阳川","上京"实乃"上陉"之误,两地皆位于炭山(金莲川草原)范围,并对清人认为"爪忽都"亦指金莲川的观点提出了不同的意见。 相似文献
53.
陈志刚 《中国边疆史地研究》2015,25(2):132-139,183
考察新疆哈密民田是了解近代哈密社会变迁的一条有效途径。道光年间,在林则徐主持下哈密出现了第一块民田。民国初年,哈密屯田民田化使民田面积进一步扩展。20世纪30年代,哈密回王世袭特权被取消,札萨克制下的土地朝民田方向发展。同时,哈密县政府限制清真寺的世俗权力,维吾尔人与汉人之间开始民田买卖,逐渐形成"你中有我,我中有你"的经济关系。 相似文献
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Latent trajectory models for space‐time analysis: An application in deciphering spatial panel data
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Li An Ming‐Hsiang Tsou Brian H. Spitzberg Dipak K. Gupta J. Mark Gawron 《Geographical analysis》2016,48(3):314-336
This article introduces latent trajectory models (LTMs), an approach often employed in social sciences to handle longitudinal data, to the arena of GIScience, particularly space‐time analysis. Using the space‐time data collected at county level for the whole United States through webpage search on the keyword “climate change,” we show that LTMs, when combined with eigenvector filtering of spatial dependence in data, are very useful in unveiling temporal trends hidden in such data: the webpage‐data derived popularity measure for climate change has been increasing from December 2011 to March 2013, but the increase rate has been slowing down. In addition, LTMs help reveal potential mechanisms behind observed space‐time trajectories through linking the webpage‐data derived popularity measure about climate change to a set of socio‐demographic covariates. Our analysis shows that controlling for population density, greater drought exposure, higher percent of people who are 16 years old or above, and higher household income are positively predictive of the trajectory slopes. Higher percentages of Republicans and number of hot days in summer are negatively related to the trajectory slopes. Implications of these results are examined, concluding with consideration of the potential utility of LTMs in space‐time analysis and more generally in GIScience. 相似文献
56.
Characterization of a Historical Cannonball from the Fortress of San Juan De Ulúa Exposed to a Marine Environment
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M. Hernandez M. Hernandez‐Escampa C. Abreu J. Uruchurtu M. Bethencourt A. Covelo 《Archaeometry》2016,58(4):610-623
Metallurgical analyses and chemical characterizations were carried out on historical cannonballs from the Fortress of San Juan de Ulúa, Veracruz, México. Cannonballs dating from the 18th and 19th centuries share metallurgical characteristics similar to those of material coming from a shipment of ammunition found in the wreck of a sunken French ship from the battle of Trafalgar. The analyses show that the base material is grey cast iron with a carbon equivalent of 4.94 and a ferritic–perlitic matrix, in which the high phosphorus content has led to the formation of iron phosphide compounds in conjunction with a homogeneous distribution of carbon graphite flakes of Type C. In addition, corrosion products from samples revealed the presence of various crystalline iron compounds (X‐ray diffraction), mostly highly chlorinated iron compounds identified as akaganeite. X‐ray fluorescence identified various characteristics of the corrosion products as a function of the sampling depth. FT–IR spectroscopy revealed that the main difference between the corrosion products (internal and external) is determined by the number of organic species. Differential scanning calorimetry corroborated that these corrosion products are thermally stable compounds at elevated temperatures. 相似文献
57.
A Box Containing Carpenter's Accessories from The Akko 1 Shipwreck,Israel: Archaeometallurgical Analysis of Surviving Ironwork
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The Akko 1 shipwreck was an Egyptian armed vessel, built at the beginning of the 19th century. A wooden saw handle and a box containing iron nails and two split pins were discovered towards the stern. Given their function, location and context, these were part of the ship's carpenter's tools and accessories. A methodology was developed for conducting systematic metallurgical analysis in order to understand the manufacturing process of the surviving ironwork items, as well as to enlarge our knowledge regarding ironworking technologies during the early 19th century. Such methodology may assist in the future understanding of the technological evolution of similar wrought‐iron objects. The results demonstrated that the artefacts have a wrought‐iron heterogeneous microstructure and were manufactured by hot‐working prior to surface hardening by pack carburization. 相似文献
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LOCALIZATION AND INDUSTRY CLUSTERING ECONOMETRICS: AN ASSESSMENT OF GIBBS MODELS FOR SPATIAL POINT PROCESSES
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![点击此处可从《Journal of regional science》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The objective of this paper is to assess an approach to statistical modeling of point referenced establishment data that permit inclusion of “environmental” or establishment‐specific covariates and specific forms of interestablishment interaction. Gibbs models are used to decompose the conditional intensity of the spatial point process into trend and interaction components. The trend is composed of access measures (primarily different classes of roads) and three different interaction processes are tested: Geyer, area interaction, and Strauss hard core. While the models used have proved to be useful in ecology, we are unaware of any applications to establishment or firm data. In empirical application, the models yield intuitively appealing results for the trend component, and the ability to specify the interaction component gives deeper insights into interestablishment spatial dynamics than any previously published methods. 相似文献