全文获取类型
收费全文 | 126篇 |
免费 | 18篇 |
国内免费 | 3篇 |
专业分类
测绘学 | 64篇 |
大气科学 | 2篇 |
地球物理 | 23篇 |
地质学 | 14篇 |
海洋学 | 10篇 |
天文学 | 4篇 |
综合类 | 30篇 |
出版年
2023年 | 1篇 |
2021年 | 1篇 |
2020年 | 6篇 |
2019年 | 6篇 |
2018年 | 2篇 |
2017年 | 9篇 |
2016年 | 11篇 |
2015年 | 18篇 |
2014年 | 18篇 |
2013年 | 7篇 |
2012年 | 15篇 |
2011年 | 8篇 |
2010年 | 6篇 |
2009年 | 12篇 |
2008年 | 2篇 |
2007年 | 1篇 |
2006年 | 4篇 |
2005年 | 3篇 |
2003年 | 1篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1990年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有147条查询结果,搜索用时 46 毫秒
101.
102.
The southern margin of the East European Craton: new results from seismic sounding and potential fields between the North Sea and Poland 总被引:1,自引:0,他引:1
U. Bayer M. Grad T. C. Pharaoh H. Thybo A. Guterch D. Banka J. Lamarche A. Lassen B. Lewerenz M. Scheck A. -M. Marotta 《Tectonophysics》2002,360(1-4):301-314
The extension of eastern Avalonia from Britain through the NE German Basin into Poland is, in some sense, a virtual structure. It is covered almost everywhere by late Paleozoic and younger sediments. Evidence for this terrane is only gathered from geophysical data and age information derived from magmatic rocks. During the last two decades, much geophysical and geological information has been gathered since the European Geotraverse (EGT), which was followed by the BABEL, LT-7, MONA LISA, DEKORP-Basin'96, and POLONAISE'97 deep seismic experiments. Based on seismic lines, a remarkable feature has been observed between the North Sea and Poland: north of the Elbe Line (EL), the lower crust is characterised by high velocities (6.8–7.0 km/s), a feature which seems to be characteristic for at least a major part of eastern Avalonia (far eastern Avalonia). In addition, the seismic lines indicate that a wedge of the East European Craton (EEC) (or Baltica) continues to the south below the southern Permian Basin (SPB)—a structure which resembles a passive continental margin. The observed pattern may either indicate an extension of the Baltic crust much farther south than earlier expected or oceanic crust of the Tornquist Sea trapped during the Caledonian collision. In either case, the data require a reinterpretation of the docking mechanism of eastern Avalonia, and the Elbe–Odra Line (EOL), as well as the Elbe Fault system, together with the Intra-Sudedic Faults, appear to be related to major changes in the deeper crustal structures separating the East European crust from the Paleozoic agglomeration of Middle European terranes. 相似文献
103.
Viliam Vatrt 《Studia Geophysica et Geodaetica》1999,43(2):223-227
The truncation error for the harmonic EGM96 series has been investigated on the basis of 24 242 testing points covering about 70% of the Earth's surface. No degree n of harmonics retained was found at which the series becomes divergent. The EGM96 rms diminishes with increasing n. The truncation error due to EGM96 at the physical Earth's surface has no limiting consequences. 相似文献
104.
105.
王建文 《测绘与空间地理信息》2016,(3)
利用哈尔滨市区及周边17个水准点GNSS/水准数据,与EGM2008模型所计算的高程异常进行对比,对模型计算的高程异常进行改正,得到精度达到0.05 m的高程异常值。 相似文献
106.
在陇南紫金李坝金矿钻探施工中遇强水敏性、破碎、复杂地层,普通绳索取心钻具岩心采取率低,平均采取率86.5%,回次进尺少,多在1 m以下,最小回次进尺只有20~30 cm,钻进效率低,平均台班进尺约5 m。通过使用SYZX96型绳索取心液动锤,钻进效率明显提升,平均岩心采取率提高8%,平均回次进尺提高50%,平均台月效率提高17.5%,纯钻时间增加到了60%左右。共完成6个钻孔,进尺2488 m,其中2个钻孔采用SYZX96型绳索取心液动锤,效果明显。总结出适合强水敏性、破碎、复杂地层绳索取心液动锤的使用经验,为类似地层钻探施工提供技术借鉴。 相似文献
107.
为了检验城市似大地水准面精化项目成果模型的质量,本文利用一定数量的高程异常控制点,以基于EGM2008地球重力场模型及二次曲面函数拟合的方法,构建了一套质量检验模型,其精度优于±5.0 cm。采用质量检验模型比对项目成果模型进行质量分析检验,与外业实地检测相比,检验工作量较小,对项目成果模型的质量评价更全面、可靠。 相似文献
108.
High-resolution Echo-sounding and Detection of Embedded Archaeological Objects with Nonlinear Sub-bottom Profilers 总被引:3,自引:0,他引:3
Sub-bottom profilers based on nonlinear acoustics offer many advantages especially for detecting and locating embedded objects
in shallow waters. They have a narrow beam in spite of small transducers and virtually no side lobes. It is possible to realize
mobile low-frequent sub-bottom profilers, which transmit very short sound pulses. Excellent vertical as well as horizontal
resolutions at reasonable penetrations are proven benefits of using this technique. In this paper some technical aspects are
discussed and a new experimental nonlinear scanning sub-bottom profiler system is described. Results from a field trial in
archaeological prospection are shown to illustrate the successful application in practice. 相似文献
109.
110.
以松原灌区GPS控制网为例,采用高程异常直接拟合和插值法,以及基于EGM2008重力场模型和移去-计算-恢复技术的残差二次曲面拟合和插值法,精化了测区大地水准面。首先简要介绍了研究区数据,进而探讨了高程异常的获取,在此基础上,详细介绍了二次曲面拟合的大地水准面精化和空间插值法大地水准面精化方法,结果表明,EGM2008重力场模型精度较高,对精化局域和国家大地水准面具有重要意义。 相似文献