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	Impact and Correction of Analytical Positioning on Accuracy of Zircon U-Pb Dating by SIMS 期刊论文 OAI收割 FRONTIERS IN CHEMISTRY, 2020, 卷号: 8, 页码: 8 作者: Liu, Yu; Li, Qiu-Li; Ling, Xiao-Xiao; Tang, Guo-Qiang; Li, Jiao \| 收藏 \| 浏览/下载：31/0 \| 提交时间：2021/09/29 SIMS zircon U-Pb dating positioning effect metamorphic overgrowth
	Applications of differential barometric altimeter in ground cellular communication positioning network 期刊论文 OAI收割 IET SCIENCE MEASUREMENT & TECHNOLOGY, 2020, 卷号: 14, 期号: 3, 页码: 322-331 作者: Hu, Zhengqun; Zhang, Lirong; Ji, Yuanfa \| 收藏 \| 浏览/下载：24/0 \| 提交时间：2021/12/06 cellular radio height measurement measurement errors Global Positioning System altimeters barometers least squares approximations Kalman filters surface fitting spread spectrum communication compensation matrix algebra GPS signal message structure power spectrum spread spectrum ranging signal fitting parameters least-square solution calibration compensation system noise variance matrix measurement noise variance matrix multibase station correction height information correction calculation DBA system systematic performance differential barometric altimeter ground cellular communication positioning network measurement datum distribution altitude positioning error Global Positioning System differential barometric altimetry system systematic implementation level continuous altitude measurement precise altitude measurement DBA systematic implementation aspect two dimensional curved surface fitting function sensor measurement correction filtering effect Kalman filter measuring station multiBSs navigation fusion
	SIS accuracy and service performance of the BDS-3 basic system 期刊论文 OAI收割 SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY, 2020, 卷号: 63, 期号: 6, 页码: 12 作者: \| 收藏 \| 浏览/下载：23/0 \| 提交时间：2021/12/06 BDS-3 SIS URE multipath effect broadcast ephemeris broadcast clock ionospheric model positioning accuracy
	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：23/0 \| 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