全文获取类型
收费全文 | 120篇 |
免费 | 4篇 |
出版年
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
© 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 theindustryuniversity 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