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GeoTPE: A neural network model for geographical topic phrases extraction from literature based on BERT enhanced with relative position embedding 期刊论文  OAI收割
EXPERT SYSTEMS WITH APPLICATIONS, 2024, 卷号: 235, 页码: 14
作者:  Li, Weirong;  Sun, Kai;  Zhu, Yunqiang;  Ding, Fangyu;  Hu, Lei
  |  收藏  |  浏览/下载：46/0  |  提交时间：2023/10/09
Hydromechanical Coupled Analysis of Water Inrush in a Karst Cave-Fracture Rock System: A Case Study 期刊论文  OAI收割
JOURNAL OF PERFORMANCE OF CONSTRUCTED FACILITIES, 2022, 卷号: 36, 期号: 6
作者:  Li, Hui;  Sui, Qun;  Tan, Xianjun;  Chen, Weizhong;  Chen, Enyu
  |  收藏  |  浏览/下载：17/0  |  提交时间：2023/08/02
Soil Atterberg Limits and Consistency Indices as Influenced by Land Use and Slope Position in Western Iran 期刊论文  OAI收割
Journal of Mountain Science, 2015, 卷号: 12, 期号: 6, 页码: 1471-1483
作者:  Zahra ZOLFAGHARI;  Mohamamd Reza MOSADDEGHI;  Shamsollah AYOUBI;  Hamid KELISHADI
收藏  |  浏览/下载：135/0  |  提交时间：2015/11/19
Monitoring motion and measuring relative position of the Chang'E-3 rover 期刊论文  OAI收割
RADIO SCIENCE, 2014, 卷号: 49, 期号: 11, 页码: 1080-1086
作者:  Liu, Qinghui;  Zheng, Xin;  Huang, Yong;  Li, Peijia;  He, Qingbao
收藏  |  浏览/下载：46/0  |  提交时间：2015/05/15
Morphometric Characterization and Reconstruction Effect Among Lunar Impact Craters SCI/SSCI论文  OAI收割
2014
作者:  Wang J.;  Wang J.
收藏  |  浏览/下载：22/0  |  提交时间：2014/12/24
Relative position determination of a lunar rover using the biased differential phase delay of same-beam VLBI 期刊论文  OAI收割
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY, 2011, 卷号: 54, 期号: 12, 页码: 2284-2295
作者:  Chen Ming;  Liu QingHui;  Wu YaJun;  Zhao RongBing;  Dai ZhiQiang
收藏  |  浏览/下载：26/0  |  提交时间：2015/08/19
Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Gu S.; Yan Y.; Xu K.; Jin G.
收藏  |  浏览/下载：51/0  |  提交时间：2013/03/25
With the development of aerospace remote sensing technology  the ground resolution of remote sensing camera enhances continuously. Since there is relative motion between camera and ground target when taking pictures  the target image recorded in recording media is moved and blurred. In order to enhance the imaging quality and resolution of the camera  the image motion had to be compensated. In order to abate the effect of image motion to image quality of space camera and improve the resolution of the camera  the compensation method of image motion to space camera is researched. First  the reason of producing drift angle and adjustment principle are analyzed in this paper. This paper introduce the composition and transmission principle of image motion compensation mechanism. Second  the system adopts 80C31 as controller of drift angle  and adopts stepping motor for actuators  and adopts absolute photoelectric encoder as the drift Angle measuring element. Then the control mathematical model of the image motion compensation mechanism are deduced  and it achieve the closed-loop control of the drift angle position. At the last  this paper analyses the transmission precision of the mechanism. Through the experiment  we measured the actual precision of the image motion compensation mechanism  and compared with the theoretical analysis. There are two major contributions in this paper. First  the traditional image motion compensation mechanism is big volume and quality heavy. This has not fit for the development trend of space camera miniaturization and lightweight. But if reduce the volume and quality of mechanism  it will bring adverse effects for the precision and stiffness of mechanism. For this problem  This paper designed a image motion compensation that have some advantages such as small size  light weight at the same time  high precision  stiffness and so on. This image motion compensation can be applicable to the small optics cameras with high resolution. Second  the traditional mechanism control need to corrected  fitting and iterative for the control formula of mechanism. Only in this way  we can get the optimal control mathematical model. This paper has high precision of the control formula derived. It can achieve the high precision control without fitting  It also simplify the difficulty of control mathematical model establishment. This paper designed the range of adjusting of image motion compensation mechanism between -5 +5. Based on choosing-5  -4  -3  -2  -1  0  +1  +2  +3  +4  +4 as the expectation value of the imaginary drift angle  we get ten groups of the fact data in adjusting drift angle measured. The test results show that the precision of the drift angle control system can be achieved in 1. It can meet the system requirements that the precision of the control system is less than 3'  and it can achieve the high-precision image motion compensation. 2011 SPIE.  
Relative position determination of a lunar rover using the biased differential phase delay of same-beam VLBI 期刊论文  OAI收割
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY, 2011, 卷号: 54, 期号: 12, 页码: 2284
作者:  Chen Ming;  Liu QingHui;  Wu YaJun;  Zhao RongBing;  Dai ZhiQiang
  |  收藏  |  浏览/下载：13/0  |  提交时间：2021/12/06
Relative position determination of a lunar rover using high-accuracy multi-frequency same-beam VLBI 期刊论文  OAI收割
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY, 2010, 卷号: 53, 期号: 3, 页码: 571-578
作者:  Liu QingHui;  Chen Ming;  Xiong WeiMing;  Qian ZhiHan;  Li JinLing
收藏  |  浏览/下载：45/0  |  提交时间：2015/08/18
Design and fabrication of CGH for aspheric surface testing and its experimental comparison with null lens (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
作者:  Zhao J.;  Zhang X.;  Zhang X.;  Zhang X.;  Li F.
收藏  |  浏览/下载：43/0  |  提交时间：2013/03/25
Computer-generated hologram (CGH) is an effective way to compensate wavefront in null test of aspheric surfaces and freeform surfaces. Our strategies of CGH design and fabrication for optical testing are presented  and an experiment demonstrating the compensation results of CGH and null lens is also reported. In order to design complex CGH  software was developed  with which we can design a CGH including three sections: main section for compensating wavefront in null test  alignment section for adjusting the relative position between CGH and interferometer  and fiducial section for projecting fiducial marks around the optics under test. The design result is represented in GDS II format file which could drive a laser-direct-writer- machine to fabricate a photomask. Then  a 1:1 replication process is applied to duplicate the patterns from photomask to a parallel optical substrate whose surface is error better than /60 rms. Finally  an off-axis aspheric surface was tested with CGH and null lens respectively. The test result with CGH (0.019rms) is almost the same as the result with null lens (0.020 rms). This experiment also demonstrated that fiducial marks projected by CGH can be used to guide the alignment of the optics and measurement of its off-axis distance. 2010 Copyright SPIE - The International Society for Optical Engineering.