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   388篇
  免费   20篇
  国内免费   14篇
测绘学   16篇
大气科学   13篇
地球物理   119篇
地质学   191篇
海洋学   17篇
天文学   1篇
综合类   18篇
自然地理   47篇
  2024年   3篇
  2023年   7篇
  2022年   2篇
  2021年   4篇
  2020年   6篇
  2019年   4篇
  2018年   3篇
  2017年   5篇
  2016年   7篇
  2015年   8篇
  2014年   19篇
  2013年   19篇
  2012年   18篇
  2011年   9篇
  2010年   17篇
  2009年   24篇
  2008年   47篇
  2007年   30篇
  2006年   29篇
  2005年   28篇
  2004年   16篇
  2003年   14篇
  2002年   11篇
  2001年   4篇
  2000年   13篇
  1999年   8篇
  1998年   15篇
  1997年   4篇
  1996年   7篇
  1995年   18篇
  1993年   5篇
  1992年   2篇
  1991年   3篇
  1990年   4篇
  1989年   2篇
  1988年   3篇
  1984年   2篇
  1982年   2篇
排序方式: 共有422条查询结果,搜索用时 15 毫秒
391.
A method for producing digital probabilistic seismic landslide hazard maps   总被引:41,自引:0,他引:41  
The 1994 Northridge, California, earthquake is the first earthquake for which we have all of the data sets needed to conduct a rigorous regional analysis of seismic slope instability. These data sets include: (1) a comprehensive inventory of triggered landslides, (2) about 200 strong-motion records of the mainshock, (3) 1:24 000-scale geologic mapping of the region, (4) extensive data on engineering properties of geologic units, and (5) high-resolution digital elevation models of the topography. All of these data sets have been digitized and rasterized at 10 m grid spacing using ARC/INFO GIS software on a UNIX computer. Combining these data sets in a dynamic model based on Newmark's permanent-deformation (sliding-block) analysis yields estimates of coseismic landslide displacement in each grid cell from the Northridge earthquake. The modeled displacements are then compared with the digital inventory of landslides triggered by the Northridge earthquake to construct a probability curve relating predicted displacement to probability of failure. This probability function can be applied to predict and map the spatial variability in failure probability in any ground-shaking conditions of interest. We anticipate that this mapping procedure will be used to construct seismic landslide hazard maps that will assist in emergency preparedness planning and in making rational decisions regarding development and construction in areas susceptible to seismic slope failure.  相似文献   
392.
固体废物、放射性废物处置及环境评估   总被引:5,自引:0,他引:5  
谈成龙 《铀矿地质》2000,16(4):247-250
随着经济建设的发展 ,人类从事的工农业生产、军事、科技等活动产生了大量的固体废物和放射性废物 ,严重污染了生态环境和人类自身的生存空间。评估、治理地质生态环境中的固体废物和放射性废物已成为当前地质工作中不容忽视的重要部分。  相似文献   
393.
地热学向何处去   总被引:1,自引:0,他引:1  
Based on the State-of-the-Art of Geothermics both at home and abroad,the question of "Where to go, Geothermics" has been answered in this paper. Author suggested that the Geothermicsin the future should go to:1)the deep interior of the Earth,2) the continental area,3 ) the atmosphere,4)the energy problem,5) the mining areas, 6) the oil一gas fields and finally,7) to earthquake prediclion. With the increasing demand for energy and mineral resources and under the pressure of environmental and hazard problems, Geothermics is also being experienced a stage of revolution. There exist opportunity and challenge. We should use the opportunity and face the challenge optimistically for thefurther development of Geothermics in various aspects.  相似文献   
394.
This paper is a contribution to an important aspect of the systematic and quantitative assessment of landslide hazard and risk. The focus is on site-specific and detailed assessment for rainfall-triggered landslides and, in particular, on the estimation and interpretation of the temporal probability of landsliding. Historical rainfall data over a 109-year period were analysed with particular reference to a site along the Unanderra and Moss Vale Railway Line in the State of New South Wales, Australia. It is shown that the recurrence interval of landsliding and hence annual probability of occurrence is subject to significant uncertainty and that it cannot be regarded as a constant. Accordingly landslide hazard varies spatially as well as being a function of time. For the example case study considered in this paper the annual probability of landslide occurrence was estimated to be in the range 0.026–0.172. However, the mean annual probability of landslide reactivation was estimated to be in the range 0.037–0.078. Utilisation of methods for probability assessment proposed in this paper will contribute to more realistic assessment of hazard and risk and, therefore, to more efficient risk management.  相似文献   
395.
This paper considers the problem of estimating long-term predictions of significant wave-height. A method which combines Bayesian methodology and extreme value techniques is adopted. Inferences are based on the Metropolis–Hastings algorithm implemented in an appropriate Markov Chain Monte Carlo scheme. The method is applied to obtain return values of extreme values of significant wave height collected on the northern North Sea. The results are compared with those obtained by Guedes Soares and Scotto [Guedes Soares, C. and Scotto, M.G., 2004. Application of the r-order statistics for long-term predictions of significant wave heights. Coastal Engineering, 51, 387–394].  相似文献   
396.
水下锚泊系统计算──一种单链动力分析的数值方法   总被引:1,自引:0,他引:1  
以悬链线理论为基础,采用集中质量法分析了水下锚泊系统单链动力特性,得出了在强迫振荡时锚链的开关及链动张力历时曲线。计算结果同实验结果吻合良好,说明该方法是可行的.  相似文献   
397.
Tsunamis can cause catastrophic loss of life, destruction of property, engineered structures and coastal infrastructure, and they can lead to major economic losses. Even though tsunamis are relatively rare in the Mediterranean Sea, their potential danger to cities along the Mediterranean coast cannot be neglected. In order to create awareness among the potentially affected people it is important to know the risk and vulnerability of the population and infrastructure related to a possible tsunami impact. In this work a hazard, vulnerability and risk analysis for buildings in two districts of Alexandria was carried out. Relevant input parameters were derived mainly from remote sensing and field data and were analyzed with a geographical information system (GIS). Based on historical records of past tsunamis, two inundation scenarios of 5 m and 9 m were defined and modeled applying a bath-type model. The resulting tsunami building risk zone maps showed that 12% of the buildings in El Gomrok district are at high or very high risk for the 5 m scenario, while the risk for El Montazah area is low. For the 9 m scenario, on the other hand, the majority of the buildings in both districts, 56% of El Gomrok, and 60% of El Montazah, are in the high or very high risk zone. An analysis of the building use indicated that the majority of these buildings are residential and commercial types, highlighting that the potential consequences of a tsunami could be severe. Due to the scarcity of historical data no frequency could be associated with the two selected scenarios. While both are credible we consider the 5 m scenario as possible but unlikely and the 9 m scenario as unlikely.  相似文献   
398.
399.
沙漠化危险度评价模型初探   总被引:15,自引:1,他引:15  
董玉祥 《地理科学》1995,15(1):24-29
  相似文献   
400.
云南新平2002-08-14特大滑坡泥石流灾害及防治对策   总被引:10,自引:3,他引:10  
云南新平2002—08—14发生了超过百年一遇的特大滑坡泥石流灾害。这次灾害点多、面广,几乎同时暴发。通过对灾害的实地考察,分析了灾害发生的地质、气象、地貌等方面原因。崩塌滑坡灾害沿哀牢山东坡的高山与中低山交接处分布,而泥石流灾害则沿戛洒江和现刀河的支流沟口分布,这一区域处于红河大断裂范围内。灾害主要是特大暴雨激发所致。针对本区的社会条件和自然条件,提出了防灾、减灾对策,具体分为近期措施和远期措施。  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