中国科学院机构知识库网格系统: 检索

浏览/检索结果: 共5条，第1-5条

帮助

条数/页：排序方式：
	Influence of Meteorological Factors on the Potential Evapotranspiration in Yanhe River Basin, China 期刊论文 OAI收割 WATER, 2021, 卷号: 13, 期号: 9, 页码: 13 作者: Luo, Yu; Gao, Peng; Mu, Xingmin \| 收藏 \| 浏览/下载：38/0 \| 提交时间：2021/08/19 climate change changing meteorological factors potential evapotranspiration sensitivity coefficient contribution rate dominant factor
	Long-term trends of precipitation in the North China Plain 期刊论文 OAI收割 JOURNAL OF GEOGRAPHICAL SCIENCES, 2012, 卷号: 22, 期号: 6, 页码: 989-1001 Fan, Lan(范兰); Lu, CH; Yang, B; Chen, Z 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/01/07 precipitation trend changing rate North China Plain
	Long-term trends of precipitation in the North China Plain SCI/SSCI论文 OAI收割 2012 Fan L.; Lu C. H.; Yang B.; Chen Z. 收藏 \| 浏览/下载：32/0 \| 提交时间：2014/12/25 precipitation trend changing rate North China Plain normal homogeneity test variability regression
	Earth elevation map production and high resolution sensing camera imaging analysis (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China 作者: Dai L. 收藏 \| 浏览/下载：142/0 \| 提交时间：2013/03/25 The Earth's digital elevation which impacts space camera imaging has prepared and imaging has analysed. Based on matching error that TDI CCD integral series request of the speed of image motion statistical experimental methods-Monte Carlo method is used to calculate the distribution histogram of Earth's elevation in image motion compensated model which includes satellite attitude changes orbital angular rate changes latitude longitude and the orbital inclination changes. And then elevation information of the earth's surface from SRTM is read. Earth elevation map which produced for aerospace electronic cameras is compressed and spliced. It can get elevation data from flash according to the shooting point of latitude and longitude. If elevation data between two data the ways of searching data uses linear interpolation. Linear interpolation can better meet the rugged mountains and hills changing requests. At last the deviant framework and camera controller are used to test the character of deviant angle errors TDI CCD camera simulation system with the material point corresponding to imaging point model is used to analyze the imaging's MTF and mutual correlation similarity measure simulation system use adding cumulation which TDI CCD imaging exceeded the corresponding pixel horizontal and vertical offset to simulate camera imaging when stability of satellite attitude changes. This process is practicality. It can effectively control the camera memory space and meet a very good precision TDI CCD camera in the request matches the speed of image motion and imaging. 2010 SPIE.
	Study on LD-pumped Nd:YAG laser cutter (EI CONFERENCE) 会议论文 OAI收割 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者: Zhang G.; Zhang G.; Zhang G.; Zhang J.; Zhang J. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 The theory of laser cutter and the technology neck is analyzed. We can conclude that it is almost impossible to deal with the waste thick silicon wafers which are yielded in producing silicon wafers by conventional eroding or diamond cutting when the cutting velocity equals 100mm/min while it is also unperfected with ecumenical laser cutter without good beam quality or precise laseroptics system. It is represented that high average power and high repetition rate laser with good beam quality and precise laseroptics system are pivotal to obtain excellent cutting effect such as thick groove depth double-layer 0.75mm thick silicon wafer can be penetrated.. The cross section is fine and the groove is narrow rapid cutting speed the cutting quality meets the expecting demand. fine kerf section without considering the effect of technique. Considering laser medium thermal lens effect and thermal focal length changing with pumping power using plano-convex high reflectivity mirror as the back cavity mirror to compensate the heat lens influence a /4 waveplate to compensate heat -induced birefraction utilize the Nd:YAG self- aperture effect more than 50 W average power 1.064 um IR output is obtained with beam quality factor (M2) equals 3.19. Through the LD-Pumped Nd:YAG laser cutter we developed with short focus length negative spherical aberration focusing lens double axis linear step motor positioning system suitable beam expander multiplying factor appropriate diameter of exit beam aperture proper repetition rate when the cutting velocity equals 400mm/min 0.75mm thick silicon wafer can be penetrated