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91.
唐代渤海国时期,今吉林省中东部地区的冶铁业有了较大发展;铁器的使用更加广泛,尤其是铁制生产工具已被大量应用于农、渔及狩猎各业;冶铁技术也有了一定的进步.本文拟分别介绍上述三个方面的基本情况并做出评价.  相似文献   
92.
新世纪前期旅游业发展预测   总被引:1,自引:0,他引:1  
旅游业是永恒的朝阳产业。根据世界旅游业和我国旅游业的发展态势,作从八个方面预测我国旅游业的未来。  相似文献   
93.
This paper documents a vernacular method of interpreting and safeguarding intangible heritage in an ethnic Miao village in China. Tracing the conflicting discourses of ritual in different stages of the past and the present, it shows how ritual practices were transformed by imperial Qing officials in the mid-nineteenth century, demonised and denounced as feudal superstition during the Cultural Revolution (1966–1976), exploited as cultural resources for ethnic tourism since the early twentieth century and involved in the evaluation system of intangible cultural heritage in the twenty-first century. Based on ethnographic materials collected in 2008 and 2009, this paper argues that it is the inherited vernacular narratives and ritual performances that are negotiating with the state’s constant effort of shaping the ritual through various discourses, constructing the meaning of inheritance and safeguarding the intangible heritage within the community.  相似文献   
94.
    
This study develops seismic fragility curves for vertical-pile-supported wharves commonly found in the western United States. Nonlinear time-history analyses of a two-dimensional numerical model under two ground motion suites are performed. The results show that the jumbo container cranes increase by 10.8% in the wharf deck drift. By using the experiment-based limit states, the proposed fragility curves demonstrate that, at a PGA of 0.50 g, the probabilities of exceeding slight, moderate, extensive, and complete limit states are approximately 23.0%, 7.0%, 4.0%, and 3.0%, respectively, while at a PGA of 1.00 g, the exceeding probabilities increase to 44.0%, 19.0%, 14.0%, and 11.0%, respectively.  相似文献   
95.
    
During the past decades, various analytical macroscopic models of structural walls have been developed for simulating the seismic behavior of reinforced concrete (RC) walls. Due to the inherently complicated characteristics of RC walls, macroscopic models that can capture all the important response characteristics with good accuracy and applicability are very challenging to establish. A thorough review of the four main types of mathematical macro models of RC walls, i.e., the vertical-line-element-model, the 2-D shear panel element model, the equivalent truss model and the fiber-based model, is presented to discuss the methodology behind each model and examine the corresponding merits and disadvantages. Suggestions are also made for the further research of the macro modeling of structural walls.  相似文献   
96.
    
Notwithstanding the relative abundance of bioarchaeological evidence of pre‐20th century gunshot wounds discovered at European and American archaeological sites, similar findings in East Asian countries have been very rare. In this study, we report evidence of possible gunshot wounds sustained by two individuals buried in Joseon tombs of Korea. The shapes of the trauma seemed to indicate low‐velocity projectiles, most likely musket balls. To our knowledge, this is the first bioarchaeological report specifically concerning possible gunshot‐wound evidence in East Asian skeletons recovered from archaeological fields. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
97.
    
ABSTRACT This research uses time‐series analysis under a quasi‐experimental pair‐wise matching design to examine local economic impacts of the 1993 Midwest flood. The data support the concept of overall local economic resiliency to natural disasters. The flood's impacts on total employment were minimal. Although significant drops in personal income were observed in the year of the event, the long‐run effects seemed to be negligible. This study also finds that the flood's negative impacts on agriculture were significant and long lasting to some Midwestern communities. The findings are quite stable with respect to the number of controls selected for each treated unit.  相似文献   
98.
杨有柏  翟岁显  马凤莲 《攀登》2011,30(6):61-65
本文从循环经济与金融支持的关系入手,分析了柴达木循环经济发展中金融支持的重要作用和金融支持方面存在的问题,提出了今后金融支持的思路。  相似文献   
99.
  总被引:1,自引:0,他引:1  
Recent zooarchaeological studies on water buffalo (Bubalus sp.) remains from China and south Asia question the traditional view that water buffalo were first domesticated in Neolithic China over 7000 years ago. The results from several recent population genetic studies of modern domesticated buffalo (Bubalus bubalis) are not consistent with each other, placing the original center of buffalo's domestication in south Asia, southeast Asia, or China. This paper reports a study using an ancient DNA approach to analyze water buffalo remains from Neolithic sites in north China to investigate their affinities with modern domesticated water buffalo, and to shed light on the origin of modern domesticated water buffalo in China.A 169 bp fragment of D-loop mitochondrial DNA was successfully amplified and verified for 13 of 24 bone samples obtained from seven archaeological sites along the Wei River valley in Shaanxi Province, China. The bone samples which yielded positive DNA can be dated to 8000–3600 cal. BP. The phylogenetic analysis of the obtained DNA sequences along with modern water buffalo sequences indicated that the ancient water buffalos were not the direct ancestor of modern domesticated water buffalo. However, the phylogenetic analysis, along with BLAST searches of these ancient DNA sequences, did demonstrate their relatedness to water buffalo more so than to any other bovid species, confirming the existence of indigenous wild (but now extinct) water buffalo species (B. mephistopheles) in ancient China.The DNA analysis of these ancient remains failed to establish direct links between modern domesticated water buffalo (B. bubalis) and indigenous water buffalo (B. mephistopheles) from ancient China. If further DNA studies of more ancient remains from other regions of China confirm the observation of solely indigenous water buffalo species in ancient China, it would suggest modern water buffalo might not have been first domesticated in China.  相似文献   
100.
淮河能成为中国历史上最稳定的南北政治分界线,是周代形成了\"淮汉\"政治区域的结果。西周以前,淮河流域和汉水流域间缺乏密切联系。西周立国后,淮汉两流域内王朝、夷人、土著等势力相互博弈,区域政治中心不断靠拢,人群间交往加强,最终在春秋时形成了一个统一的\"淮汉\"政治区域。这一区域长期稳定存在,使淮河南北形成了不同的政治文化传统,淮河从此成为中国历史上最稳定的南北政治分界线。\"淮汉\"政治区域形成,不仅促使中国古代政治格局由东西向转变为南北向,还推动了上古政治由血缘关系向地缘关系变革。  相似文献   
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