首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   120篇
  免费   4篇
  2023年   2篇
  2019年   4篇
  2018年   4篇
  2017年   4篇
  2016年   5篇
  2015年   3篇
  2014年   1篇
  2013年   43篇
  2012年   2篇
  2011年   2篇
  2010年   3篇
  2009年   8篇
  2008年   3篇
  2007年   4篇
  2006年   3篇
  2004年   1篇
  2003年   1篇
  2002年   6篇
  2000年   1篇
  1998年   3篇
  1997年   3篇
  1995年   1篇
  1991年   1篇
  1990年   2篇
  1989年   1篇
  1987年   2篇
  1985年   2篇
  1983年   1篇
  1982年   2篇
  1980年   1篇
  1974年   2篇
  1958年   1篇
  1954年   1篇
  1951年   1篇
排序方式: 共有124条查询结果,搜索用时 46 毫秒
81.
We report recent fieldwork on an early‐16th‐century wreck in the Stockholm archipelago, Sweden. The discovery not only provides new insights into early carvel shipbuilding and its adoption across northern Europe but manifests the changing role of ships and the nature of power and agency in the process of state formation at the dawn of the modern world. © 2012 The Authors  相似文献   
82.
83.
84.
Shipping traffic is scouring away seabed sediment in St Peter Port harbour, Guernsey. Since 1985 nine sections of well-preserved medieval ship structure have been revealed, representing at least five separate vessels. Although they seem broadly contemporary, it is not yet possible to say whether any or all were lost at the same time. With their rescue under way, research has addressed their provenance, their roles, and their relationship to Guernsey and the wider medieval world. This paper discusses ships that are of international significance today not least because they were of similar importance in their own time.
© 2004 The Nautical Archaeology Society  相似文献   
85.
86.
87.
Forty‐six bronze objects have been investigated to assess their composition and microstructure, using SEM–EDX and optical microscopy. The bronzes originate from Tell Beydar, a site in the northeastern part of Syria that was mainly occupied during the third millennium bc . The compositional results of the metals show a clear chronological sequence in the use of the alloying elements arsenic and tin. In addition, the microstructure indicates advancement in the metalworking techniques that were used.  相似文献   
88.
Comparative localization of academic and industrial spillovers   总被引:12,自引:0,他引:12  
This paper studies geographic localization of academic and industrialknowledge spillovers. Using data on US research and developmentlaboratories that quantify spatial aspects of learning aboutuniversities and firms as well as the locations of closely affiliateduniversities and firms, I find that academic spillovers aremore localized than industrial spillovers. I also find thatlocalization is increased by nearby stocks of R&D, but reducedby laboratory and firm size. These results on localized academicspillovers reflect the dissemination of normal science and theindustry–university cooperative movement, which encouragefirms to work with nearby universities, so that geographic localizationcoincides with the public goods nature of academic research.This situation contrasts with relations to other firms, wherecontractual arrangements are often needed to access proprietaryinformation, often at a considerable distance.  相似文献   
89.
90.
The management of indigenous irrigation systems has received increasing attention both from social science researchers and from those development agents who seek to change them, or to find in them a model for organizing newly developed irrigation schemes. This article discusses how water is allocated within one such irrigation system, the hill furrow irrigation of the Marakwet escarpment in Kenya. It describes the ‘formal rules’ of water rights, giving particular attention to the issue of gender with respect to water rights. It then discusses the ‘working rules’ relevant to water allocation, involving various informal practices of sharing, buying and stealing. The implications of this complexity for understanding the operation of indigenous farmer-managed irrigation systems are examined.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号