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171.
城市土地利用变化的不透水面覆盖度检测方法 总被引:4,自引:0,他引:4
通过分析城市中不透水面数量和分布的变化与城市土地利用变化之间的对应关系, 综合中、高分辨率遥感数据各自的优势, 运用CART算法进行城市不透水面覆盖度(ISP)遥感估算, 基于ISP制图结果对城市土地利用变化进行检测。以山东省泰安市为例开展实验研究, 结果表明, 与传统的变化检测方法相比, 基于ISP的变化检测方法, 不仅能够反映土地利用类型转换的潜在信息, 而且可以灵活地量化定义和解释城市用地变化情况。这种方法为城市土地利用变化信息的提取和分析提供了一种新的思路, 可以作为现有变化检测方法的有益补充。 相似文献
172.
According to national early warning practice for geo-hazards from 2003 to 2005, it is systematically concluded that the basic characteristics of geo-hazards, early warning method and forecast result based on the geological maps of China in a scale 1∶6 000 000. With the contrast of different characters between sustained rainfall and typhoon rainfall inducing geo-hazards, the disaster reduction result and some problems are preliminarily analyzed. Some basic recognition is that early warning to geo-hazards is feasible, national scale forecast is only to call attention, but can't immediately be used to disaster reduction decision-making. And, the future direction is to build a united disaster reduction framework of early warning system including national, provincial and county levels based on weather factors in different scale of area. 相似文献
173.
基于点目标分析的InSAR技术检测地表微小形变的研究 总被引:1,自引:0,他引:1
近年来,由合成孔径雷达干涉测量技术(InSAR)技术发展而来的时间序列影像点目标分析技术已发展成为大范围地提取地表微小形变信息的关键技术。本研究针对地表形变检测中经常出现的时间、空间去相干问题和大气效应等问题,从常规的合成孔径雷达差分测量技术(D-InSAR)入手,深入探讨了以永久散射体(PSI)和相干目标分析(CTA)方法为代表的点目标分析技术原理和方法,阐述了它们的特点和优势。最后,介绍了CTA方法对提取长时间地表形变场的具体应用实例,说明其方法的有效性和可靠性。 相似文献
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175.
A major limitation for wide application of Synthetic Aperture Radar (SAR) remote sensing in mapping landslide surface displacements is the intrinsic gap between the ultimate objective of measuring three-dimensional displacements and the limited capability of detecting only one or two-dimensional displacements by repeat-pass SAR observations of identical imaging geometries. Although multi-orbit SAR observations of dissimilar viewing geometries can be jointly analyzed to inverse the three-dimensional displacements, the reliability of inversion results might be highly questionable in case of continuous motion because of the usually asynchronous acquisitions of multi-orbit SAR datasets. Aiming at this problem, we proposed an approach of retrieving time series three-dimensional displacements from multi-angular SAR datasets for step-like landslides in the Three Gorges area in this article. Firstly, time series displacements of a common ground target in the azimuth and line-of-sight (LOS) direction can be estimated using traditional methods of SAR interferometry (InSAR) and SAR pixel offset tracking (POT), respectively. Then, a spline fitting and interpolation procedure was employed to parameterize the displacement history in the sliding/dormant periods of step-like landslides and estimate displacements from multi-angular observations for identical date series. Finally, three-dimensional displacements can be inverted from these synchronized multi-angular measured displacements in traditional ways. As a case study, the proposed method was applied to retrieve the three-dimensional displacements history of the Shuping landslide in the Three Gorges area, China. Comparisons between SAR-measured displacements and measurements of global positioning system (GPS) showed good agreement. Furthermore, temporal correlation analyses suggest that reservoir water level fluctuation and rainfall are the two most important impact factors for the Shuping landslide stability. 相似文献
176.
177.
A comprehensive study on geothermal history of the Turpan-Hami Basin by vitrinite reflectance, fluid inclusion geothermometry,
apatite fission track and40Ar-39Ar dating displays that the main effects influencing geotemperature distribution are burial depth of the basement, heat flow,
magmatic activities, as well as tectonic movement, having a rugulation to be higher in the east and north, lower in the west
and south, as well as higher in the past and lower at the present. The heat of the mantle source and the Indo-China tectonic
thermal event have extremely influenced maturation of source rocks of the upper Lower Permian and the Middle and Upper Triassic
in the lndo-China epoch. While, the geothermal gradient and the weak tectonic geothermal event of the Early Yanshan Movement
provided necessary heat for the maturation of source rock in coal-bearing strata of the Middle and Lower Jurassic. 相似文献
178.
基于影像匹配一致性,结合小波变换与分析,提出了一种适用于遥感影像的有失真压缩编码方法。考察了不同的压缩倍率对影像匹配偏移中误差的影响。 相似文献
179.
180.