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161.
甘肃省地应力资料分析及近期地震趋势判断   总被引:1,自引:0,他引:1       下载免费PDF全文
甘肃省地应力资料分析及近期地震趋势判断张国英杨国栋(中国地震局兰州地震研究所,兰州730000)主题词应力分析异常特征甘肃地震趋势判断1资料甘肃省现有5个地应力观测站,分布在其东部和南部.近5年来,在全国资料评比中,这5个站的资料均被评为优秀,其中刘...  相似文献   
162.
Akindofinformationonshorttermandimminentearthquakeprecursors—researchonatmosphericelectricfieldanomaliesbeforeearthquakesJI...  相似文献   
163.
The long-time practice of observational research on earthquake prediction has shown that the information on short-term and imminent earthquake precursors can hardly be detected, but it is very important for practical and effective earthquake prediction. The result of analysis and study in this paper has shown that the anomaly of quasi-static atmospheric electric field may be a kind of reliable information on short-term and imminent earthquake precursors. On such a basis, the 20 years’ continuous and reliable data of atmospheric electric field observed at the Baijiatuan seismic station are used to study the correlation between the anomalies in seismic activity and relative quiet periods bear on the occurrence of near earthquakes within 200 km range around Beijing after the Tangshan earthquake. The observational results recently reported before hand in written form and earthquakes that actually occurred in near field in corresponding time periods are compared and analyzed. The efficacy of these written prediction opinions about near earthquakes in the recent 10 years is tested. From the test results, the brilliant prospect that the anomaly of quasi-static atmospheric electric field may really become a reliable mark for making short-term and imminent earthquake predictions is discussed. Besides, as a preliminary step, some judgment indexes for predicting earthquakes by use of the observational data of atmospheric electric field before earthquakes are put forward. In the last part, it is pointed out that it would be possible to obtain more believable judgment indexes for determining the three elements of near earthquakes before greater earthquakes (M S≥5) only if a relatively reasonable station network (2–4 stations every 10 000 km2) is deployed and further investigation is made. Contribution No. 97A0040, Institute of Geophysics, State Seismological Bureau, China. This subject is sponsored by Program No. 95-04-05-01-04, State Seismological Bureau, China.  相似文献   
164.
地震预报专家系统ESEP 3.0   总被引:3,自引:0,他引:3  
近期研制成功的地震预报专家系统ESEP 3.0将模糊系统、神经网络与专家系统技术相结合,引入了驾驭式的推理机制,除具有第一代专家系统的符号推理与解释功能、以及第二代专家系统的学习功能外,还具有较强的人机交互能力,是一个全新的专家系统。ESEP 3.0由知识编辑、机器学习、驾驭式模糊推理机和解释等4个子系统组成,本文介绍了系统的组成和概况。  相似文献   
165.
知识表示是专家系统建造中的一个关键环节,知识表示方法的好坏直接关系到系统的智能水平和解决问题的能力。在地震预报专家系统ESEP3.0中有多种知识表示方法,本文介绍了该系统的结构知识、地震学和前兆预报知识、机器学习知识、综合预报知识、确定异常证据可信度知识以及支持知识等多种知识表示方法,提出了确定异常证据可信度模型。这些知识表示方法可以很好地表示各类地震预报知识。  相似文献   
166.
随着人工智能技术的发展,使得利用计算机的高速度、高效率、高准确度等优点,结合人工预报天气的思维过程,进行智能化天气预报成为可能。台风预报专家系统就是一个成功的应用,本文对我们进行台风预报的方法进行了阐述,并详细介绍了该专家系统的设计和实现方法。实践表明,台风专家系统预报准确,具有很高的应用价值。  相似文献   
167.
In the last twenty years, participatory forums have been increasingly used to manage water basins around the world. The implementation of participatory forums has sought to prevent and overcome conflicts by bringing together a multiplicity of stakeholders in joint efforts to deliberate, achieve mutually agreed upon decisions, and distribute limited water resources. Different literature streams have evaluated the benefits and challenges of participatory forums in practice, such as the difficulties some forums have had when confronting existing power structures. Separately, research on water governance has paid particular attention to the ways in which expert discourses are used by traditionally powerful actors to exclude less powerful others. This paper draws from the literatures on participation and discourses in environmental governance to empirically investigate how expert discourses may empower or disempower certain actors in four basin councils – two in Peru and two in Brazil. Through qualitative thematic analysis of 116 interviews and observation notes, we specifically investigate the extent to which expert discourses in these basin councils help empower previously excluded actors. Our findings indicate stakeholder interests that are not, or cannot, be expressed within the frame of expert discourses are often marginalized. This suggests participation has made it possible for some previously excluded actors to have a voice, yet their potential influence is seemingly confined to a restricted space beyond which their voices will have little effect.  相似文献   
168.
SS—Y伸缩仪常见异常现象分析   总被引:1,自引:1,他引:0  
针对地震台站SS-Y伸缩仪常见异常现象进行分析判断,给出维护方法,以便于观测、维护人员识别,对地震前兆台站管理人员有一定指导意义。  相似文献   
169.
Rapid growth in the water transport system demands the construction of more port and harbour structures. Berthing structures are constructed in ports and harbours to provide facilities such as berthing and mooring of vessels, loading and unloading of cargo and embarking and disembarking of passengers. Quays, wharfs, piers, jetties and dolphins are the most widely used berthing structures. The construction and maintenance of these structures are very expensive and, therefore, the most economical design should be adopted. These structures will be checked against limit state of crack, which is important in respect to preventing corrosion. A knowledge based expert system, KNOWBESTD, has been developed using LEVEL5 OBJECT for the design of berthing structures. This paper describes the development of KNOWBESTD and illustrates the design of a typical berthing structure.  相似文献   
170.
陈学忠 《地震》2007,27(2):41-45
提出了一种以统计学中的假设检验为基础的地震趋势判别指标提取的方法, 以中国大陆1930年以来的年地震频次为例, 给出了判定中国大陆地区发生7级以上地震的5级以上地震年频次判别指标。 研究结果表明, 当5级以上地震年频次Na5≥31时, 可判定其后第6年不发生7级以上地震, 为无震判别条件; 当Na5≤10时, 可判定其后第6年会发生7级以上地震, 为有震判别条件; 当11≤Na5≤30时, 不能判定其后是否会发生7级以上地震; 当Na5≥24时, 可判定其后第6年无7级以上地震发生, 为无震判别条件, 犯错误的可能性为5%。 2002年的5级以上地震年频次Na5=7, 满足有震判别条件, 因此可以作出2008年中国大陆地区可能发生7级以上地震的判定。 2003年的5级以上地震年频次Na5=28, 满足无震判别条件Na5≥24, 可判定2009年不会发生7级以上地震, 犯错误的可能性为5%。 该方法也适用于其他地震活动和前兆异常判别指标的提取。  相似文献   
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