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   82篇
  免费   2篇
  2023年   1篇
  2022年   1篇
  2021年   1篇
  2020年   3篇
  2019年   3篇
  2018年   3篇
  2017年   9篇
  2016年   4篇
  2013年   26篇
  2012年   6篇
  2011年   3篇
  2010年   2篇
  2009年   2篇
  2008年   3篇
  2007年   3篇
  2006年   2篇
  2004年   2篇
  2002年   1篇
  2000年   3篇
  1996年   1篇
  1994年   1篇
  1992年   1篇
  1991年   1篇
  1990年   1篇
  1982年   1篇
排序方式: 共有84条查询结果,搜索用时 31 毫秒
71.
Histomorphometric semi-automatic image analysis of cross-sections of 101 femoral diaphyseal bone sections were performed to reconsider to what degree osteon remodelling in the outer cortex is affected by age. The data were analysed statistically using the generalized least squares method. The model estimation, which includes the covariance matrix of four single equation residuals, improves the accuracy of age determination. The standard deviation, however, of age prediction remains 12.58 years. An experimental split of the data was made in order to demonstrate that the use of subgroups gives a false impression of higher precision of age determination. The present study demonstrates that determination of age at death through microscopic bone morphometry is considerably less precise than generally stated in the literature.  相似文献   
72.
73.
During the Late Roman and Byzantine period, natron glass was made from its raw materials in a limited number of primary production centres in Egypt and Syro-Palestine. For the earlier Hellenistic and Roman period, no primary furnaces have been found and the location of primary production during this era remains unclear. Ancient authors such as Strabo and Pliny the Elder suggest that glassmaking sands were found near the River Belus (Israel), in Egypt, near the mouth of the Volturno River (Italy) and also in Spain and France. However, primary production in the western part of the Mediterranean is not supported by any direct archaeological evidence and possible sand raw materials from these regions have never been evaluated for their suitability to produce glass.  相似文献   
74.
Johan Andersson 《对极》2012,44(4):1081-1098
Abstract: In recent years, the local authorities in London's historic Bloomsbury district have carried out a number of refurbishments of the area's public squares. These landscaping schemes have typically been labelled “historical restorations” in attempts to predetermine the evaluation criteria as “historic” rather than political, social and aesthetic. Focusing on Russell Square and Bloomsbury Square, this paper illustrates how the “restorations” were selective: the introduction of gates and railings and the removal of planting were not primarily designed to restore these historical gardens, but reflect a surveillance‐friendly ideal of urban space, specifically introduced to displace the men who used these squares for cruising. Through a detailed review of archival material from both mainstream and gay media, I illustrate the shifting forms of policing and landscaping in Bloomsbury's squares, while also highlighting how homonormative capital has colluded with the regulation of public space in this part of London.  相似文献   
75.
Environmental change has a human dimension, and has had so for at least the last 10 000 years. The prehistoric impact of people on the Arctic landscape has occasionally left visible traces, such as house and field structures. More often than not, however, the only evidence available is at the microscopic or geochemical level, such as fossil insect and seed assemblages or changes in the physical and chemical properties of soils and sediments. These records are the subject of SEAD, a multidisciplinary database and software project currently underway at Umeå University, Sweden, which aims to create an online database and set of tools for investigating these traces, as part of an international research infrastructure for palaeoecology and environmental archaeology.  相似文献   
76.
The present paper examines the importance of integrating geographical effects into the analysis of social networks. Specifically, we study the impacts of spatial distance and territorial borders on information exchange within two European cross-border regions where there is evidence of extensive cross-border political interaction in the domain of public transportation. We use exponential random graph models to review how these spatial factors influence policy interaction. We show how the effect of distance on the exchange of information between organizations is less obvious than it seems at first sight, when we control for endogenous networks effects with which it tends to be confounded. We also explore moderating effects among the spatial factors studied and in particular how the effect of distance affects information exchange by territoriality. While the probability of interaction decreases with distance in the context of domestic ties, distance does not exert the same friction when it comes to cross-border ties. These findings suggest that borders are not necessarily a barrier to interaction and that peripheral actors located in border regions may bridge distance in order to access strategic information they do not have access to within their territorial jurisdiction and is likely concentrated in foreign decision centers.  相似文献   
77.
78.
79.
Chronometric studies of charcoal production remains are largely based on 14C-dating of associated charcoal. Owing to intrinsic limitations, however, this method provides no meaningful time resolution for post-1650 CE features. We investigate the potential of optically stimulated luminescence (OSL) dating of heated sandy sediments as an alternative and complementary tool for dating charcoal kiln remains. Seven samples from five relic charcoal kilns and 11 complementary samples from the underlying sandy substrate are used. Through a range of procedural tests, we demonstrate that the single-aliquot, regenerative-dose procedure in combination with OSL signals from quartz allows determining equivalent doses both accurately and precisely. For four of the five investigated kilns, OSL ages are consistent with independent age information from 14C-dating and written sources. Especially for post-1650 CE features, the precision can be significantly better than that of 14C-dating, and we highlight the potential of OSL dating for distinguishing, relatively, between charcoal production phases with an unprecedented time resolution. We conclude that the approach is a promising alternative to 14C.  相似文献   
80.
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