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	Reliability analysis of slopes considering spatial variability of soil properties based on efficiently identified representative slip surfaces 期刊论文 OAI收割 JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING, 2020, 卷号: 12, 期号: 3, 页码: 642-655 作者: Wang, Bin; Liu, Leilei; Li, Yuehua; Jiang, Quan \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2021/05/25 Slope reliability analysis Spatial variability Representative slip surfaces (RSSs) Response surface method (RSM) Random field simulation
	Spatio-temporal distribution of vascular plant species abundance on Qinghai-Tibet Plateau 期刊论文 OAI收割 JOURNAL OF GEOGRAPHICAL SCIENCES, 2019, 卷号: 29, 期号: 10, 页码: 1625-1636 作者: Fan Zemeng; Bai Ruyu; Yue Tianxiang \| 收藏 \| 浏览/下载：25/0 \| 提交时间：2020/03/23 spatial simulation method vascular plant species abundance spatio-temporal distribution scenario analysis Qinghai-Tibet Plateau
	Spatio-temporal distribution of vascular plant species abundance on Qinghai-Tibet Plateau 期刊论文 OAI收割 JOURNAL OF GEOGRAPHICAL SCIENCES, 2019, 卷号: 29, 期号: 10, 页码: 1625-1636 作者: Fan Zemeng; Bai Ruyu; Yue Tianxiang \| 收藏 \| 浏览/下载：11/0 \| 提交时间：2020/03/23 spatial simulation method vascular plant species abundance spatio-temporal distribution scenario analysis Qinghai-Tibet Plateau
	Comparison and simulation of subpixel imaging modes for linear CCD (EI CONFERENCE) 会议论文 OAI收割 2012 3rd International Conference on Information Technology for Manufacturing Systems, ITMS 2012, September 8, 2012 - September 9, 2012, Qingdao, China 作者: Li Y.; He B.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/25 Subpixel technique of linear CCD is effective to enhance the spatial resolution without increasing the focal length of optics and reducing the pixel size. To compare image quality of two main subpixel imaging modes quincunx sampling and four-point sampling a method to quantitatively evaluate image quality of subpixel based on MTF was proposed. The MTF of quincunx and four-point sampling modes were derived. Analytical results shows that theoretical limiting resolution of quincunx sampling and four-point sampling is improved to 1.4 and 1.86 times respectively and MTF values at Nyquist frequency of two modes are increased by 0.1106 and 0.1679 respectively. MTFA in (0 0.5) of two subpixel imaging modes were calculated and results illustrates that four-point sampling offers much more improvement with image quality than quincunx sampling at the cost of double amount of data. A model for simulating subpixel imaging using Matlab was established and simulation results of spoke target verify the theoretical analysis. (2012) Trans Tech Publications Switzerland.
	Design of stable image platform on airborne camera (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Advanced Design and Manufacturing Engineering, ADME 2011, September 16, 2011 - September 18, 2011, Guangzhou, China 作者: Yang L.; Yang L. 收藏 \| 浏览/下载：15/0 \| 提交时间：2013/03/25 Modulation transfer function resulting from random vibration was analyzed. To conclude that the effect of angular displacement was the major factor. Allowable MTF degradation was represented and 34dB reduction was achieved at frequency of 100HZ. With the help of MSC.ADAMS simulation software and convert allowable MTF degradation into stable system design parameters simulated curve proves correct for isolator which can guide perfect design for stabilization system. Based on the spatial mechanism and translational principle of parallelogram and the irrotational displacement mechanism was tested by optical method an irrotational displacement isolator was developed. It can meet the requirements of irrotational displacement and damp. An instance was given coupled angle is less than 8? it can satisfy the demand of aerial imaging. (2011) Trans Tech Publications.
	Method of improving the accuracy of image motion measurement for panoramic aerial cameras (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, April 26, 2010 - April 29, 2010, Dalian, China 作者: Jia P. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 To improve the accuracy of image motion measurement for panoramic aerial cameras the paper proposed a method of real-time image motion measurement based on 2D spatial correlation. An auxiliary area CCD is positioned paralleled to the main linear TDI CCD in the focal plane of the camera. For every frame of the image sequence taken by the auxiliary CCD a prediction on the displacement of the current image in the flight direction is made based on the forward image motion velocity. The current and the reference images are combined together for 2D-correlation which products an image motion vector. By decomposing the vector both the forward and pendulum-swing image motions can be determined. The demanding computational requirements for the real-time 2D-correlation are covered by a joint transform optical correlator. Simulation test results show that the accuracy is improved and the measurement error is within 0.2 pixels for input images with SNR=1 dB. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Panoramic aerial camera image motion measurement using a hybrid system (EI CONFERENCE) 会议论文 OAI收割 2010 3rd IEEE International Conference on Computer Science and Information Technology, ICCSIT 2010, July 9, 2010 - July 11, 2010, Chengdu, China 作者: Jia P. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 Image motion compensation is significantly important for aerial camera photograph. To execute the compensation we must determine the image motion exactly. This paper proposes a method of real-time image motion measurement for panoramic aerial cameras based on image processing using a hybrid system. Two cameras are simultaneously used in the hybrid system. One main linear CCD for imaging while the other auxiliary low resolution high frame rate area CCD for determining the image motion based on 2D spatial correlation. The demanding computational requirements for the real-time 2D spatial correlation are covered by a joint transform optical correlator. Simulation test results show that the accuracy is improved and the measurement error is within 0.2 pixels for input images with SNR=1 dB. 2010 IEEE.
	Study of high precision non-contact measurement based on CCD (EI CONFERENCE) 会议论文 OAI收割 4th International Conference on Information Technology and Applications, ICITA 2007, January 15, 2007 - January 18, 2007, Harbin, China Lin L.; Yun F. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 In this paper a method that measures relatively positionrelationshipquickly and accurately between two vehicles both on a horizontal plane is introduced. When the linear CCD camera placed on the end of manipulator scans two point targets located on the other vehicle by virtue of the spatial intersection principle and trigonometry theorem the relative position relationship between the loading vehicles and launching ones can be gotten(i.e. the spatial coordinate parameters of x y z and the angle displacement ). At the same time the paper establishes that the measurement error of length is less than 1mm by analysis of thee rror analysis and the simulation of computer. The angle displacement is less than 3 which satisfies the technical requests. So the vehicle orientation and loading missiles can be both done at the shortest time. It meets the demand of centralization between the measurement and execution. Forboth automatic transshipment and spatial position relationship measurement the study is valuable. And the manipulator is measure device as well as executive one so that residual inherent error decreases according to identical reference principle. Therefore the measure precision can be improved greatly.
	Application of linear CCD for position measurement (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China 作者: Fu Y.; Liu L.; Liu L. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 A method that measures relatively position relation between two vehicles fleetly and accurately that are both on a horizontal plane is proposed in the article. When manipulator rotates horizontally that of angle is less than 26 the linear CCD vidicon that is on the end of manipulator on the loading vehicle scans two point targets that are on the launching vehicle which satisfies technical requests. So the method is feasible. The research is not only significant for missile of automatic transshipment and then we can utilize spatial intersection principle and trigonometry theorem to get relatively position relationship. I.e. the coordinate parameters: x but also is valuable in theoretic research on method of measuring spatial position relationship. y z . Error analysis and the simulation on computer validate: the measurement error of length is less than 0.84mm