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991.
丽江7.0级地震土木结构房屋破坏比和损失比 总被引:1,自引:0,他引:1
本根据丽江地震区113个自然村震害调查资料,对不同烈度区土木房屋不同破坏等级破坏比的分布特点进行了初步研究,对破坏比与烈度的关系进行了统计分析,并给出了相应的统计关系,另外,通过实地调查,给出了本次地震土木结构房屋不同破坏等级的损失比。 相似文献
992.
在金沟岭、汪清县、十里坪幅1:5万区域地质矿产调查中发现区内内生矿床主要受断裂构造控制。我们在断裂中系统采集100多个岩石化学测量样品,对分析结果进行方差,判别,R型分析等数理统计,对区内可能的容矿断裂的含矿性作出了定量评价。 相似文献
993.
将抗剪强度C,φ值考虑为一个整体进行统计分析,提出了在某个法向压应力区间内,满足某个风险率要求的计算公式,及若干条直线的平均值、方差、标准差、标准值的计算方法。说明了新老抗剪强度统计方法之间的内在联系。 相似文献
994.
Barry Boots 《GeoJournal》2001,53(4):339-345
995.
David M. Cairns 《Geografiska Annaler: Series A, Physical Geography》2001,83(3):157-168
Winter desiccation-induced foliage loss at high-elevation locations is an important determinant of positive carbon balance for trees and thus influences the location of the alpine treeline ecotone. In this study, data are presented that describe the amount of winter desiccation incurred by krummholz growth forms of subalpine fir ( Abies lasiocarpa (Hook) Nutt.) at treeline locations in Glacier National Park, Montana, USA, for the winter of 1998/1999. An average 8.68% of the krummholz canopy was lost due to desiccation.
Winter desiccation is not predictable based on any single environmental variable. When outliers are removed, winter desiccation shows a strong correlation with elevation ( r = 0.97). Patch level winter desiccation amounts are, however, highly predictable from elevation, slope, aspect and topographic context when considered together. In general, injury increases with elevation and on more southwesterly facing hillslopes. High slopes and sheltered locations decrease winter desiccation.
Within patches, most winter desiccation is located at the windward edge of the patch. This trend may be modified by the presence of leaders above the mean canopy surface of the krummholz patch, or by local microtopographic features such as dead branches or the proximity of large rocks.
The winter of 1998/1999 was a high winter desiccation year compared to the two previous winters. The winter of 1998/1999 had high snowfall, and meltout did not occur until later than the previous two winters. The extended period of snow cover is hypothesized to be one of the causes of the increased winter desiccation for the 1998/1999 winter. 相似文献
Winter desiccation is not predictable based on any single environmental variable. When outliers are removed, winter desiccation shows a strong correlation with elevation ( r = 0.97). Patch level winter desiccation amounts are, however, highly predictable from elevation, slope, aspect and topographic context when considered together. In general, injury increases with elevation and on more southwesterly facing hillslopes. High slopes and sheltered locations decrease winter desiccation.
Within patches, most winter desiccation is located at the windward edge of the patch. This trend may be modified by the presence of leaders above the mean canopy surface of the krummholz patch, or by local microtopographic features such as dead branches or the proximity of large rocks.
The winter of 1998/1999 was a high winter desiccation year compared to the two previous winters. The winter of 1998/1999 had high snowfall, and meltout did not occur until later than the previous two winters. The extended period of snow cover is hypothesized to be one of the causes of the increased winter desiccation for the 1998/1999 winter. 相似文献
996.
Robust multiple-station magnetotelluric data processing 总被引:19,自引:0,他引:19
Gary D. Egbert 《Geophysical Journal International》1997,130(2):475-496
997.
对日本兵库县南部地震震灾统计时程曲线的初步分析 总被引:4,自引:0,他引:4
本文作者制作了日本兵库县南部地震震灾统计时程曲线,归纳了该曲线的特点,并对此进行了相应的分析。同时,针对我国地震灾情调查和评估提出了一些意见。 相似文献
998.
利用新疆天山地区丰富的地震资料,通过天山地区灾害性地震的空间分布、历史地震烈度分布、地震地表破坏特征、地震灾害损失论述了新疆天山地震灾害特征,分析了灾害成因。 相似文献
999.
公路桥区域性震害预测 总被引:8,自引:1,他引:8
地震区桥址地基失效或岸坡失稳,对于桥梁的震害程度有明显的影响。本文基于这一特点,将历史地震桥梁震害资料,依据无液化场地及可液化场地或岸坡失稳的影响,分别以几个主要灾害影响因素对应于不同震害程度进行数理统计,并应用模糊数学方法,综合评判在未来地震中大面积范围桥梁可能出现的震害状态,它对于地震区部署桥梁的抗震防灾工作有着重要的现实意义。 相似文献
1000.
YU-LONG XIE JI-HONG WANG YI-ZENG LIANG LI-XIAN SUN XIN-HUA SONG RU-QIN YU Department of Chemistry Chemical Engineering Hunan University Changsh People''s Republic of China 《地理学报(英文版)》1993,(6)
Principal component analysis (PCA) is a widely used technique in chemometrics.The classical PCAmethod is,unfortunately,non-robust,since the variance is adopted as the objective function.In thispaper,projection pursuit (PP) is used to carry out PCA with a criterion which is more robust than thevariance.In addition,the generalized simulated annealing (GSA) algorithm is introduced as anoptimization procedure in the process of PP calculation to guarantee the global optimum.The resultsfor simulated data sets show that PCA via PP is resistant to the deviation of the error distribution fromthe normal one.The method is especially recommended for use in cases with possible outlier(s) existingin the data. 相似文献