全文获取类型
收费全文 | 17082篇 |
免费 | 4766篇 |
国内免费 | 785篇 |
专业分类
测绘学 | 738篇 |
大气科学 | 102篇 |
地球物理 | 14988篇 |
地质学 | 4143篇 |
海洋学 | 432篇 |
天文学 | 342篇 |
综合类 | 1020篇 |
自然地理 | 868篇 |
出版年
2024年 | 43篇 |
2023年 | 146篇 |
2022年 | 314篇 |
2021年 | 554篇 |
2020年 | 515篇 |
2019年 | 733篇 |
2018年 | 904篇 |
2017年 | 934篇 |
2016年 | 841篇 |
2015年 | 965篇 |
2014年 | 1105篇 |
2013年 | 1431篇 |
2012年 | 1110篇 |
2011年 | 1116篇 |
2010年 | 993篇 |
2009年 | 1126篇 |
2008年 | 951篇 |
2007年 | 928篇 |
2006年 | 906篇 |
2005年 | 916篇 |
2004年 | 808篇 |
2003年 | 775篇 |
2002年 | 624篇 |
2001年 | 578篇 |
2000年 | 552篇 |
1999年 | 386篇 |
1998年 | 363篇 |
1997年 | 353篇 |
1996年 | 347篇 |
1995年 | 292篇 |
1994年 | 286篇 |
1993年 | 221篇 |
1992年 | 178篇 |
1991年 | 105篇 |
1990年 | 70篇 |
1989年 | 51篇 |
1988年 | 43篇 |
1987年 | 18篇 |
1986年 | 14篇 |
1985年 | 8篇 |
1984年 | 6篇 |
1983年 | 2篇 |
1979年 | 15篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1954年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
Thomas O. Graff 《The Professional geographer》2006,58(1):54-64
The three largest discount chains, Kmart, Target, and Wal‐Mart, have adopted the supercenter format for expansion. This article examines the locations of and the competition among these supercenters. Wal‐Mart has the greatest number of supercenters and is driving the expansion of the supercenter format. Both Kmart and Target have clustered their supercenters in a small number of metropolitan markets. In contrast to Wal‐Mart and Kmart, Target has focused on a middle‐class rather than a blue‐collar clientele. Now Kmart is struggling following a declaration of bankruptcy. Wal‐Mart has largely defeated its supercenter competitors and now is confronting the major grocery chains for grocery sales. 相似文献
122.
123.
This study investigates the extent to which people's views on the causes and preventability of earthquake damage might be influenced by their degree of exposure to hazard as well as what information they have been given about the hazard. The results show that the provision of hazard zoning information influences judgements on preventability and causes of damage, but this effect depends on the degree of hazard faced by residents. In low hazard zones, information leads to the view that causes are manageable, whereas in high hazard zones information may induce a degree of fatalism. The use of public information in risk management needs to take into account the degree of risk faced by the recipients. 相似文献
124.
125.
The Dahuiyeh (Zarand) earthquake of 2005 February 22 in central Iran: reactivation of an intramountain reverse fault 总被引:3,自引:0,他引:3
126.
Zoltán Wéber 《Geophysical Journal International》2006,165(2):607-621
127.
128.
Matthew J. Spittal Frank H. Walkey John McClure Richard J. Siegert Kimberley E. Ballantyne 《Natural Hazards》2006,39(1):15-29
Preparedness is a key dependent variable in many studies examining people’s response to disasters such as earthquakes. A feature
of many studies on this issue, however, is the lack of attention given to psychometric issues when constructing measures of
preparedness. With regard to earthquake preparation, for example, many studies could be greatly improved by the use of a valid
and reliable measure of preparedness. This research developed such a measure that assessed both low-level preparedness, such
as having an emergency kit, and high-level preparedness, such as altering home structures to mitigate damage. Studies of Wellington
(New Zealand) residents using two samples totalling n=652 showed that 23 items measuring these different aspects of earthquake preparation could be combined into a reliable, valid,
unifactorial scale. This brief scale should have utility in multivariate studies of earthquake preparation, either as a dependent
variable, where preparation is the outcome variable of primary interest, or as one of several independent variables, where
preparation and other measures predict another outcome variable. 相似文献
129.
Potential of High-Resolution Satellite Data in the Context of Vulnerability of Buildings 总被引:1,自引:2,他引:1
High-resolution space-borne remote sensing data are investigated for their potential to extract relevant parameters for a
vulnerability analysis of buildings in European countries. For an evaluation of large earthquake scenarios, the number of
parameters in models for vulnerability is reduced to a minimum of relevant information such as the type of building (age,
material, number of storeys) and the geological and spatial context. Building-related parameters can be derived from remote
sensing data either directly (e.g. height) or indirectly based on the recognition of the urban structure type in which the
buildings are located. With the potential of a fully- or semi-automatic inventory of the buildings and their parameters, high-resolution
satellite data and techniques for their processing are a useful supporting tool for the assessment of vulnerability. 相似文献
130.
Seismic Hazards Assessment for Radioactive Waste Disposal Sites in Regions of Low Seismic Activity 总被引:4,自引:0,他引:4
Clark H. Fenton John Adams Stephen Halchuk 《Geotechnical and Geological Engineering》2006,24(3):579-592
A comparative tectonic quiescence and lack of earthquakes make the stable centres of continents attractive for siting long-term
radioactive waste storage facilities. The low rates of deformation in such regions, however, make it difficult to characterize
their long-term seismotectonic behaviour, leading to uncertain estimates for the very low probability hazard estimates required
by society. In an attempt to overcome the deficiency of both contemporary seismicity and paleoseismic data in central Canada,
we have used earthquake histories from regions with similar seismotectonic characteristics from around the world. Substituting
space for time, we estimate a long-term rate per 106 km2 of 0.004 magnitude ≥6 earthquakes per annum, of which 33–100% might rupture to the surface. 相似文献