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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   
992.
刘祜  陆士立  焦仓文  袁明  柯丹 《铀矿地质》2005,21(6):364-369
本文介绍了虚拟仪器的基本概念、基本结构和特点,详细阐述了根据虚拟仪器技术开发的电磁成像仪的硬件结构、采集软件的功能和系统的总体特点.  相似文献   
993.
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   
994.
本文介绍了成像式宇宙噪声接收机技术和数据分析方法,通过对南极中山站成像式宇宙噪声接收机在2003年10月底太阳风暴期间的观测数据进行分析,得到了相应的极区电离层的吸收效应,它们主要是强度为2. 7dB的宇宙噪声突然吸收和强度高达31dB持续4d的极盖吸收。  相似文献   
995.
996.
利用小波变换检测超声成象测井图象边缘的研究   总被引:1,自引:1,他引:1  
对超声成象测井图象中的小波变换边缘的检测方法进行了研究。介绍了小波变换边缘检测的原理 ,阐述了基于小波变换模极大值的超声成象测井图象边缘检测的算法 ,最后给出了应用实例。实践表明 :利用小波变换检测超声成象测井图象边缘的检测方法 ,可有效地弥补传统边缘检测算法的不足 ,在有效地抑制噪声的同时 ,提高了检测细小边缘成分的精度。该方法可以从不同尺度下的边缘图象中检测出不同细节的地质特征 ;小尺度下的检测结果可用于分析超声成象测井图象中的地质体的细小结构 ,大尺度下的检测结果可用于分析超声成象测井图象的地质体的整体结构  相似文献   
997.
斜井成像测井资料处理中地层产状的校正方法及应用   总被引:1,自引:0,他引:1  
邹长春  史謌 《物探与化探》2002,26(6):463-466
从成像测井图像中直接提取的地层产状,只反映测井仪器坐标系中的结果。对于井眼倾斜的情况,只有进行了井斜校正后,才能获得真实的地层产状。作者推导了成像测井地层产状计算结果的井斜校正算法,并将其应用于苏北大陆科学钻探PPⅡ孔超声成像测井资料处理中,给出了应用实例。  相似文献   
998.
Public domain software has been developed for remote exposure control of a consumer digital camera for use in photomicroscopy. A computer-controlled shutter release and remote control of various camera functions are essential to avoid mechanical disturbance of the microscope and slide during the imaging procedure. These features have previously been available only with expensive professional models. The digital images of diatom specimens obtained with this system captured the same detail as conventional photographs. The setup can therefore be used as a cost-effective tool for documenting taxonomic information of microscopically small organisms. In combination with the fast data transfer rates available via the Internet, microscopical studies can now be performed faster, more reliably, and more consistently.  相似文献   
999.
机载激光遥感成像的激光回波波形数字化技术   总被引:2,自引:0,他引:2  
首先介绍了机载遥感成像技术的基本原理,讨论了其关键组成部分的地面目标激光回波波形数字化电路的设计及其组成特点,叙述了该波形数字化电路的时序设计和数据存储结构,最后讨论了波形数字化结果的数据预处理方法及相关问题,得到了系统试验运行中获取的激光回波的有关预处理结果,它们将作为进一步生成地面三维图像和目标分类的数据源。  相似文献   
1000.
A unique multispectral imager and an associated multispectral analysis framework are described which together constitute a new diagnostic tool for auroral research. By acquiring spatial and spectral data simultaneously, multispectral imaging allows one to exploit physical connections between auroral morphology and the auroral optical spectrum in a way that sequential spectral imaging cannot. The initial research focus is on imaging the transition in the incident energy spectrum during the formation of discrete arcs—that is, when the precipitating population is characterized by <1 keV electrons. A technique is presented which uses two spectral bands (centered at 4278 and 7325 Å) to extend the effective dynamic range of passive imaging to much lower energies.  相似文献   
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