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	Species asynchrony stabilises productivity under extreme drought across Northern China grasslands 期刊论文 OAI收割 JOURNAL OF ECOLOGY, 2021, 卷号: 109, 期号: 4, 页码: 1665-1675 作者: Muraina, Taofeek O.; Xu, Chong; Yu, Qiang; Yang, Yadong; Jing, Minghui \| 收藏 \| 浏览/下载：19/0 \| 提交时间：2023/02/24 above-ground productivity biodiversity coordinated experiments ecosystem function and structure Eurasia steppe global change ecology grassland communities terrestrial ecosystem
	Ground experiments of Chang'e-5 lunar regolith penetrating radar 期刊论文 OAI收割 ADVANCES IN SPACE RESEARCH, 2019, 卷号: 63, 期号: 10, 页码: 3404-3419 作者: Xiao, Yuan; Su, Yan; Dai, Shun; Feng, Jianqing; Xing, Shuguo \| 收藏 \| 浏览/下载：44/0 \| 提交时间：2020/03/10 Chang'e-5 (CE-5) Lunar Regolith Penetrating Radar Ground experiments
	Ground experiments on a liquid bridge facility for TG-2 space laboratory 会议论文 OAI收割 65th International Astronautical Congress 2014: Our World Needs Space, IAC 2014, Toronto, ON, Canada, September 29, 2014 - October 3, 2014 作者: Duan L(段俐); Kang Q(康琦) 收藏 \| 浏览/下载：54/0 \| 提交时间：2017/05/27 Convection modes Critical temperature difference Ground experiments Oscillation frequency Space experiments Space laboratory Surface deformation Temperature differences
	Small aircraft CAN bus signal acquisition equipment (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China Chen C.-Q. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 Small aircraft often used RS485 bus. But with the complexity of the small aircraft's subsystems increase and the progress of field bus technology CAN bus systems in small aircraft use more and more widely. How to record real-time flight experiment data on the small aircraft's CAN bus and provide test data for reproducing the process of a small aircraft flying is very important. This paper presents a design method of signal acquisition device it can be used for small aircraft flying field experiment. 2010 IEEE. as the main chip with DSP2812 SJA1000 as CAN controller CTM1050 as the CAN transceiver CF card as storage media. Gives the diagram of its hardware and software design process. Combined with the background of a small aircraft testing the instrument for data acquisition when the ground experiments and flight progress. Experimental data show that the design of high reliability and CAN signals can effectively complete the record
	Analysis of laser jamming to satellite-based detector (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China 作者: Guo L.-H.; Guo R.-H.; Wang S.-W. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 The reconnaissance satellite communication satellite and navigation satellite used in the military applications have played more and more important role in the advanced technique wars and already become the significant support and aid system for military actions. With the development of all kinds of satellites anti-satellite laser weapons emerge as the times require. The experiments and analyses of laser disturbing CCD (charge coupled detector) in near ground have been studied by many research groups but their results are not suitable to the case that using laser disturbs the satellite-based detector. Because the distance between the satellite-based detector and the ground is very large it is difficult to damage it directly. However the optical receive system of satellite detector has large optical gain so laser disturbing satellite detector is possible. In order to determine its feasibility the theoretical analyses and experimental study are carried out in the paper. Firstly the influence factors of laser disturbing satellite detector are analyzed in detail which including laser power density on the surface of the detector after long distance transmission and laser power density threshold for disturbing etc. These factors are not only induced by the satellite orbit but dependence on the following parameters: laser average power in the ground laser beam quality tracing and aiming precision and atmospheric transmission. A calculation model is developed by considering all factors which then the power density entering into the detector can be calculated. Secondly the laser disturbing experiment is performed by using LD (laser diode) with the wavelength 808 nm disturbing CCD 5 kilometer away which the disturbing threshold value is obtained as 3.5510-4mW/cm2 that coincides with other researcher's results. Finally using the theoretical model the energy density of laser on the photosensitive surface of MSTI-3 satellite detector is estimated as about 100mW/cm2 which is largely exceed the disturbing threshold and therefore verify the feasibility of using this kind of laser disturbing the satellite-based detector. According to the results. using the similar laser power density absolutely saturate the requirements to laser disturbing satellite-based detector. If considering the peak power of pulsed laser even decrease laser average power it is also possible to damage the detector. This result will provide the reliable evidences to evaluate the effect of laser disturbing satellite-based detector. 2009 SPIE.
	Resolution performance of extreme ultraviolet telescope (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China 作者: Yang L.; Chen B.; Chen B.; Liang J.-Q.; Ni Q.-L. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 Extreme Ultraviolet Telescope (EUT) will image solar corona in four EUV narrow bandpasses defined by multilayered coatings deposited on normal incidence optics. In order to make sure it will get sub-arcsecond angular resolution in the mission we have to test its resolution performance on ground. The EUT is aligned by Zygo interferometer first and a global wavefront error of 0.152 peak to valley is obtained ( = 632.8nm ). Because of the difficulty of angular resolution test for EUT at its operating wavelengths we test its optical performance at visible and UV band. The method is to place the resolution test-target on the focal plane of collimator and illuminate the target by visible and UV light espectively then the collimated light will go through EUT and image at focal plane on CCD. By analysis of the images obtained in experiments we conclude that the angular resolution of EUT is 1.22 at visible light ( = 570nm ) which is very close to diffraction limit (1.20) and according to these results we estimate that the operational wavelength resolution is better than 0.32 meets design requirements. While for UV light the angular resolution is 1.53 that is different from diffraction limit (0.53) the error comes mainly from large pixel of EUV camera. 2009 SPIE.
	Research on the radiometric calibration of TDI CCD remote camera (EI CONFERENCE) 会议论文 OAI收割 ICO20: Illumination, Radiation, and Color Technologies, August 21, 2005 - August 26, 2005, Changchun, China Liu Y.-X.; Hao Z.-H. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 The radiometric calibration of the Time delay and integration Charge-coupled Device (TDI CCD) imaging system is a necessary part in the manufacturing TDI CCD camera. The radiometric calibration of the TDI CCD remote sensing camera is done in the State Key Laboratory of Applied Optics. The integration sphere is used for simulating different radiance which is decided by the different sun vertex angle and different reflectivity of the ground. The parameters of the gain and stage of the TDI CCD remote sensing camera are given through the analyzing of outcome of the experiment. The outcomes are used in the practice and the errors are discussed in the end of the experiments.