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991.
在对矿物光谱特征理解与归纳的基础之上,对矿物光谱特征进行知识化表达,利用数理逻辑和一定的判别规则实现对高光谱遥感影像矿物的自动识别与批量化信息提取。在ENVI平台上,利用IDL语言开发了高光谱遥感影像矿物分层自动识别模(Mineral Auto-identification Module Basedon Spectral Identification Tree:MAIM-SIT)。该模块已经在新疆东天山哈密地区利用HyMap数据、西藏驱龙地区利用Hyperion数据以及美国Cuprite地区利用AVIRIS数据成功地进行了矿物识别,可识别的矿物或矿物组合可达10种以上,基本实现了高光谱矿物信息提取的智能化与批处理能力。 相似文献
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Ananth Krishna N. S. Gopinath N. S. Hegde N. K. Malik 《Journal of Earth System Science》2005,114(6):739-748
The Chandrayaan-1 mission proposes to put a 550 kg lunarcraft into Geostationary Transfer Orbit (GTO) using the Polar Satellite
Launch Vehicle (PSLV) which will subsequently be transferred into a 100 km circular lunar polar orbit for imaging purposes.
In this paper, we describe certain aspects of mission strategies which will allow optimum power generation and imaging of
the lunar surface.
The lunar orbit considered is circular and polar and therefore nearly perpendicular to the ecliptic plane. Unlike an Earth
orbiting remote sensing satellite, the orbit plane of lunar orbiter is inertially fixed as a consequence of the very small
oblateness of the Moon. The Earth rotates around the Sun once a year, resulting in an apparent motion of Sun around this orbit
in a year. Two extreme situations can be identified concerning the solar illumination of the lunar orbit, noon/midnight orbit,
where the Sun vector is parallel to the spacecraft orbit plane and dawn/dusk orbit, where the Sun vector is perpendicular
to the spacecraft orbit plane. This scenario directly affects the solar panel configuration. In case the solar panels are
not canted, during the noon/midnight orbit, 100% power is generated, whereas during the dawn/dusk orbit, zero power is generated.
Hence for optimum power generation, canting of the panels is essential. Detailed analysis was carried out to fix optimum canting
and also determine a strategy to maintain optimum power generation throughout the year. The analysis led to the strategy of
180‡ yaw rotation at noon/midnight orbits and flipping the solar panel by 180‡ at dawn/dusk orbits. This also resulted in
the negative pitch face of the lunarcraft to be an anti-sun panel, which is very useful for thermal design, and further to
meet cooling requirements of the spectrometers.
In principle the Moon’s surface can be imaged in 28 days, because the orbit chosen and the payload swath provide adequate
overlap. However, in reality it is not possible to complete the imaging in 28 days due to various mission constraints like
maximum duration of imaging allowed keeping in view the SSR sizing and payloads data input rate, time required for downlinking
the payload data, data compression requirements and visibility of the lunarcraft for the Bangalore DSN. In each cycle, all
the latitudes are swept. Due to the constraints mentioned, only 60‡ latitude arc coverage is possible in each orbit. As Bangalore
DSN is the only station, half of the orbits in a day are not available. The longitudinal gaps because of non-visibility are
covered in the next cycle by Bangalore DSN. Hence, in the firstprime imaging season, only 25% of the prime imaging zones are covered, and an additional threeprime imaging seasons are required for a full coverage of the Moon in two years. Strategy is also planned to cover X-ray payload coverage considering
swath and orbit shift. 相似文献
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基于VSP的透射PS波成像 总被引:1,自引:0,他引:1
利用弹性波动方程进行了非零偏移距VSP波场的数值模拟,通过偏振投影和中值滤波技术相结合进行波场分离,对分离后的反射P波和透射PS波利用动校正(NMO)和VSPCDP叠加技术进行成像。成像结果表明:透射PS波成像与反射P波成像具有同样良好的效果,而且透射PS波成像是反射波成像很好的补充。利用透射PS波成像不需要增加数据采集的成本,所以透射波成像技术将会在石油工业中被广泛采用。 相似文献
999.
大庆油田东部深层某井区火山岩气藏岩性复杂、储层参数计算以及流体性质识别困难。根据岩性组合规律建立火山岩解释模型,对深层的火山岩测井资料进行处理与解释。联合使用成像测井分析结果、岩性分类和多井对比等方法,提高了测井解释精度和解释符合率。计算的孔隙度、饱和度和渗透率为提交天然气地质储量提供了基础参数。 相似文献
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Geomorphological observations, geoelectrical soundings and photogrammetric measurements of surface movement on the Muragl glacier forefield were used to obtain an integrative analysis of a highly complex glacial and periglacial landform consisting of a push moraine, creeping permafrost and permafrost‐free glacial till in close proximity. Electrical resistivity tomography is considered as an important multifunctional geophysical method for research in periglacial permafrost related environments. Joint application with measurements of surface displacements offers a promising tool for investigating periglacial landforms related to ice‐rich permafrost for a more comprehensive characterization of permafrost characteristics and geomorphological interpretation of periglacial morphodynamics. The patchy permafrost distribution pattern described in this paper is determined by several factors, including the sediment characteristics, the snow cover distribution and duration, the aspect and the former glacier distribution and thermal regime. Recent and modern permafrost dynamics within the glacier forefield comprise aggradation, degradation and permafrost creep. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献