全文获取类型
| 收费全文 | 204篇 |
| 免费 | 19篇 |
| 国内免费 | 14篇 |
专业分类
| 测绘学 | 91篇 |
| 大气科学 | 8篇 |
| 地球物理 | 15篇 |
| 地质学 | 70篇 |
| 海洋学 | 7篇 |
| 综合类 | 15篇 |
| 自然地理 | 31篇 |
出版年
| 2022年 | 1篇 |
| 2020年 | 2篇 |
| 2019年 | 1篇 |
| 2018年 | 5篇 |
| 2017年 | 5篇 |
| 2016年 | 11篇 |
| 2015年 | 14篇 |
| 2014年 | 16篇 |
| 2013年 | 19篇 |
| 2012年 | 17篇 |
| 2011年 | 25篇 |
| 2010年 | 15篇 |
| 2009年 | 22篇 |
| 2008年 | 25篇 |
| 2007年 | 20篇 |
| 2006年 | 5篇 |
| 2005年 | 15篇 |
| 2004年 | 10篇 |
| 2003年 | 3篇 |
| 2002年 | 3篇 |
| 2001年 | 2篇 |
| 2000年 | 1篇 |
排序方式： 共有237条查询结果，搜索用时 15 毫秒
1.
在地质工作程度较低、基岩出露较好的地区,充分重视遥感数据的使用,可有效地缩小工作靶区,提高找矿效率。该文以甘肃省席芨水地区为研究区,基于ETM+遥感数据,利用多元数据分析、准归一化、掩膜分析、主成分分析、密度分割等方法,从Landsat7ETM+数据中提取金矿化蚀变信息。在遥感地质解译的基础上,充分分析提取的羟基异常和铁染异常,结合区域地质特征、区域成控矿条件及区域物化探异常特征等,尽可能去掉假、弱异常。结果表明:该方法能有效消除植被、水系、阴影等干扰信息的影响,从遥感数据载体中提取微弱的金矿化蚀变信息。提取的矿化蚀变信息与断裂构造具有较好的相关性,主要分布于断裂构造交会处、断裂与岩体交会处等成矿优势部位,对今后的找矿工作具有一定的指导意义。 相似文献
2.
全球气候变暖给整个地球的生态环境带来巨大的影响,在全球气候变暖背景下,绿洲热场的变化严重影响绿洲的生态稳定性,利用遥感卫星影像来监测热场分布规律具有很强的现实意义。采用Landsat7 ETM+热红外波段定量反演晴空状态下干旱区典型绿洲地表真实温度,运用影像叠加分析、直方图比对、缓冲区分析、空间自相关分析及剖面线分析方法,分析其热场分布规律。结果表明,绿洲热场分布具有显著的正的空间自相关特性,Moran’s I值为0.5489,z检验值为48.44,同时呈现出显著的局部空间集聚现象; 就全局而言,热场分布规律为水体温度<耕地温度<林草地温度<城镇温度<裸地温度<盐碱地温度,均温分别为21.65 ℃、27.86 ℃、35.59 ℃、36.52 ℃、40.06 ℃、42.07 ℃; 就局部而言,盐碱地温度低于周边裸地温度,盐碱地平均温度比周边300 m、900 m、1 500 m缓冲区裸地的均温分别低0.59 ℃、0.44 ℃、0.26 ℃。水体、城镇、盐碱地、裸地的温度波动较小,热力景观单一,热场分布均匀,而耕地和林草地的温度梯度大,热力景观复杂多样,热场分布极不均匀。绿洲荒漠交错带的面积较大,它可以降低荒漠对绿洲的热力侵蚀,对保护绿洲有重要作用。 相似文献
3.
Stijn Hantson Emilio Chuvieco 《International Journal of Applied Earth Observation and Geoinformation》2011
The recent free availability of Landsat historical data provides new potentials for land-cover change studies. Multi-temporal studies require a previous radiometric and geometric homogenization of input images, to better identify true changes. Topographic normalization is one of the key steps to create consistent and radiometricly stable multi-temporal time series, since terrain shadows change throughout time. This paper aims to evaluate different methods for topographic correction of Landsat TM-ETM+ data. They were assessed for 15 ETM+ images taken under different illumination conditions, using two criteria: (a) reduction of the standard deviation (SD) for different land-covers and (b) increase in temporal stability of a time series for individual pixels. We observed that results improve when land-cover classes where processed independently when applying the more advanced correction algorithms such as the C-correction and the Minnaert correction. Best results were obtaining for the C-correction and the empiric–statistic correction. Decreases of the SD for bare soil pixels were larger than 100% for the C-correction and the empiric–statistic correction method compared to the other correction methods in the visible spectrum and larger than 50% in the IR region. In almost all tests the empiric–statistic method provided better results than the C-correction. When analyzing the multi-temporal stability, pixels under bad illumination conditions (northern orientation) improved after correction, while a deterioration was observed for pixels under good illumination conditions (southern orientation). Taken this observation into account, a simple but robust method for topographic correction of Landsat imagery is proposed. 相似文献
4.
5.
高空间分辨率影像与多光谱影像融合,为影像处理提供了更加丰富的资源,有利于进行影像的分析和制图。本文以庐山及其周边区域的2009年5月11日LandsatETM＋与2009年5月6日SPOT5影像数据为例,对典型的融合方法进行了对比评价。融合方法包括加权融合法,HIS变换,改进的HIS变换,高频调制融合法（频域采用Butterworth滤波器．指数滤波器）,HSV变换,Brovey变换,CN变换,PC变换,Gram—Schmidt变换11种方法。评价指标为相关系数、信息熵、标准差、平均梯度、相对偏差、标准偏差。结果表明,不同的融合结果突出的侧重点不同。加权融合法、Grain—Schmidt变换,PC变换方法突出了影像的信息量丰富度、清晰度,提高空间分辨率能力。CN波谱锐化,改进的HIS变换,BWO高频调制融合,指数高频调制融合方法光谱保真度较好。改进的HIS变换,BWO高频调制融合,CN波谱锐化,指数高频调制融合法在空间分辨率及光谱保真度、清晰度、信息丰富度方面的能力较均衡。 相似文献
6.
7.
基于两种遥感影像的郯庐断裂带构造解译浅析 总被引：1，自引：0，他引：1
吴哲 《测绘与空间地理信息》2011,34(1):181-182,185
利用光谱信息丰富的常规光学遥感(Landsat-7 ETM)和Google earth影像作为主要数据源,运用ETM1,4,7波段进行假彩色图像合成,综合两种不同的影像于ArcGIS平台上对郯庐断裂构造特征进行分析.首先确定线性构造,通过线性构造周围水系、地形特征推测断裂的存在,得到研究区域内郯庐断裂遥感影像图,基本确... 相似文献
8.
TerraSAR-X satellite acquires very high spatial resolution data with potential for detailed land cover mapping. A known problem with synthetic aperture radar (SAR) data is the lack of spectral information. Fusion of SAR and multispectral data provides opportunities for better image interpretation and information extraction. The aim of this study was to investigate the fusion between TerraSAR-X and Landsat ETM+ for protected area mapping using high pass filtering (HPF), principal component analysis with band substitution (PCA) and principal component with wavelet transform (WPCA). A total of thirteen land cover classes were identified for classification using a non-parametric C 4.5 decision tree classifier. Overall classification accuracies of 74.99%, 83.12% and 85.38% and kappa indices of 0.7220, 0.8100 and 0.8369 were obtained for HPF, PCA and WPCA fusion approaches respectively. These results indicate a high potential for a combined use of TerraSAR-X and Landsat ETM+ data for protected area mapping in Uganda. 相似文献
9.
Mohsin Jamil Butt 《水文研究》2012,26(24):3689-3698
Estimation of snow cover characteristics (snow grain size, snow contamination, snow depth and liquid water content) from satellite data are important components for many hydrological models used for the water resource management. This research aimed to use Landsat ETM+ (Enhanced Thematic Mapper Plus) data to estimate the snow pack characteristics in northern Pakistan. The Normalized Difference Snow Index (NDSI), Snow Contamination Index (SCI) and Snow Grain Size Index (SGI) are applied to estimate the snow cover characteristics in northern Pakistan for the first time. Qualitative maps are generated to show the snow cover distribution, snow contamination concentration and snow grain size distribution over snow cover area. Our results show that NDSI, SCI and SGI can be effectively used to identify snow area, contaminated snow and ageing snow. Furthermore, the results of the current study indicate that in the HKH region 99.8% of the snow is least contaminated whereas 94.50% of the area has fine snow grain size. As no such attempt in the past has been made in northern Pakistan, it is envisaged that the results of this study will be helpful in planning remote sensing data for the water resource management and in characterizing the snow cover for the climate change applications in the region. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
10.