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521.
建筑物震害空间分布模拟GIS方法 总被引:3,自引:0,他引:3
提出了一个基于GIS技术的建筑物震害空间分布模拟方法,该方法首先利用GIS的模拟活化技术把地震影响场,建筑震害预测等分析模型形成可供空间分析使用的二次数据,并纳入城市基础数据库之中,构成综合基础数据库。然后利用GIS把多重空间数据进行空间复合,给出城市建筑物震害的空间分布及其统计特征,并识别出城市建筑物的重灾区。最后利用东营市建筑区为例,说明该方法的实用性和有效性。 相似文献
522.
评估结构抗震性能的能量方法 总被引:9,自引:0,他引:9
在抗震概念设计中,虽然确立了一些准则,但这些准则基本上是定性的,目前尚缺乏简明的定量评估准则。本文结合抗震设计规范提出了一种对结构抗震性能评估的能量方法,可用于抗震设计方案的定量评估和比较,以及场地对结构影响的定量评估,减震方案的评估。该方法在实际工程设计中的应用取得预期效果。 相似文献
523.
本文是在对《地震现场建筑物安全鉴定》(GB18208.2—2001)国家标准进行研究和理解的基础上,对应用中出现的问题进行了分析。为了使在现场安全鉴定的工程技术人员能够较为科学、规范化地使用该标准,我们对国标中定性条款进行了量化处理,并提出了应用两层的模糊评价模型对受震房屋的震损进行鉴定的方法。最后对地震现场建筑物安全性鉴定智能辅助系统总体设计作了说明,并简要阐述了该系统的应用价值。 相似文献
524.
基于边缘检测的编组法直线提取 总被引:2,自引:0,他引:2
对直线相位编组法进行改进,提出了一种在边缘检测基础上进行相位编组提取直线的方法。该方法充分利用了图像的梯度和幅值信息,能够比较准确地提出物体的边缘直线,克服了相位编组法中边缘灰度幅值信息利用不够、容易生成多边缘、不利于突出物体主边缘直线的缺点。在大比例尺域市房屋的提取中能发挥比较好的辅助作用。 相似文献
525.
The spatial relationship between areas with severely damaged (red-tagged) buildings and areas with large strains in the soil (indicated by reported breaks in the water distribution system), observed during the 1994 Northridge earthquake, is analysed. It is shown that these areas can be separated almost everywhere. Minimal overlapping is observed only in the regions with very large amplitudes of shaking (peak ground velocity exceeding about 150 cm s−1). One explanation for this remarkable separation is that the buildings on ‘soft’ soils, which experienced nonlinear strain levels, were damaged to a lesser degree, possibly because the soil absorbed a significant portion of the incident seismic wave energy. As a result, the total number of severely damaged (red-tagged) buildings in San Fernando Valley, Los Angeles and Santa Monica may have been reduced by a factor of two or more. This interpretation is consistent with the recorded peak accelerations of strong motion in the same area. It is concluded that significant reduction in the potential damage to wood frame single family dwellings may be expected in areas where the soil experiences ‘large’ strains (beyond the linear range) during strong earthquake shaking, but not significant differential motions, settlement or lateral spreading, near the surface. 相似文献
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528.
The access to the complete reports sent in answer of a Royal enquire relative to the 1755 earthquake (Archivo Historico Nacional, 1756) provided us with information more comprehensive than that included in the analysis of such documents prepared by the Spanish Royal Academy of History in 1756 (Real Academia de la Historia, 1756). With such data, we have made a new study of the shock centred mainly in the following points: number of victims, source parameters (including moment magnitude and epicentral location),intensity map and seismogeological effects compared with those expected from the EMS-98. Relevant results from this analysis are: a new intensity attenuation law for earthquakes from the region of the 1755 shocks and first approximation damage probability matrices for buildings of the types common in the XVII to XIX centuries affected by large, distant earthquakes. 相似文献
529.
从云南省大姚县6.2级地震看我国小城镇和村镇房屋存在的抗震问题 总被引:11,自引:0,他引:11
在2003年云南省大姚县7月21日6.2级地震调查的基础上,结合以往所收集的地震震害资料,阐述了小城镇和村镇建筑在地震作用下的破坏形式并分析了原因,提出了相应的防御技术措施,最后对现阶段我国小城镇和村镇建筑在抗御地震方面存在的紧迫问题提出建议。 相似文献
530.
Closed‐form solution for seismic response of adjacent buildings connected by hydraulic actuators with linear quadratic Gaussian (LQG) controllers is presented in this paper. The equations of motion of actively controlled adjacent buildings against earthquake are first established. The complex modal superposition method is then used to determine dynamic characteristics, including modal damping ratio, of actively controlled adjacent buildings. The closed‐form solution for seismic response of the system is finally derived in terms of the complex dynamic characteristics, the pseudo‐excitation method and the residue theorem. By using the closed‐form solution, extensive parametric studies can be carried out for the system of many degrees of freedom. The beneficial parameters of LQG controllers for achieving the maximum response reduction of both buildings using reasonable control forces can be identified. The effectiveness of LQG controllers for this particular application is evaluated in this study. The results show that for the adjacent buildings of different dynamic properties, if the parameters of LQG controllers are selected appropriately, the modal damping ratios of the system can be significantly increased and the seismic responses of both buildings can be considerably reduced. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献