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	梭梭（Haloxylon ammodendron）对地下水位变化的响应和适应性研究学位论文 OAI收割北京: 中国科学院大学, 2020 作者: 米晓军 \| 收藏 \| 浏览/下载：90/0 \| 提交时间：2021/12/10 地下水埋深饱和膨压渗透调节物质同化枝生长胡伯尔值 Groundwater depth full turgor point osmotic adjustment substances leaf growth rates Huber value
	Effect of Facet Displacement on Radiation Field and Its Application for Panel Adjustment of Large Reflector Antenna 期刊论文 OAI收割 Chinese Journal of Mechanical Engineering, 2017, 卷号: 30, 期号: 3, 页码: 578-586 作者: Wang, Wei; Lian, Peiyuan; Zhang, Shuxin; Xiang, Binbin; Xu, Qian \| 收藏 \| 浏览/下载：48/0 \| 提交时间：2019/12/09 Reflector antennas Surface accuracy Radiation field Reflector antenna mechanical factors Electromechanical effects Panel adjustment Singular value decomposition (SVD) microwave holography surface measurement radio telescope deformation metrology matrix Engineering
	An Active Surface Adjustment Method for Large High-frequency Antennas Considering Gain and Boresight 会议论文 OAI收割 Shenyang, China, Aug 10-12,2016 作者: Xiang Binbin; Feng, Shufei; Zhang, Jie; Zhong Jianfeng; Tang, Baofu \| 收藏 \| 浏览/下载：42/0 \| 提交时间：2017/07/04 Active Surface Electromechanical Coupling Model Adjustment Value
	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：47/0 \| 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.
	Support technique of ultra thin mirror in space optics (EI CONFERENCE) 会议论文 OAI收割 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, November 2, 2005 - November 5, 2005, Xian, China 作者: Ren J.-Y.; Gao M.-H. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 With the development of space optical system the technique of ultra thin mirror come forth and is paid more attention because of less difficulty in machining low cost lightweight no disassembly during detecting and maintaining. The key technique takes advantage of deformation of ultra thin mirror as the influence of environment to adjust the surface figure. Its accuracy meets requirement. An analysis method is based on finite element analysis (FEA) and many items including the amount of support points the way of arrangement the optimum design of support component are studied. The finite element method was used to analyze the mirror and some different mirror support schemes. The principal aim of the mirror analysis is to get numbers of support points and the ways of the support. There are three schemes including 12-6-1 12-8-1 and 16-8-1 models. Deformation of deadweight is calculated under the three conditions. The way of 16-8-1 is more suitable than the designs of other two. The support subassembly is amended to meet with the mirror surface RMS in the range of 30m. Deformation of the mirror with support structure has been calculated. The result is 16.52nm lower than a quarter of the wavelength which indicates the feasibility of the support scheme applied to mirror. Theoretical result for the best way of support is presented. The result of analysis shows that requirement surface figure could be met through adjusting support points. It predicts feasibility of the support technique and provides theoretical value for active adjustment in the laboratory. At present support and adjusting experiment of ultra thin mirror is being carried on.
	SCISSORS DIFFERENCE AND ITS IMPACTS ON ECONOMIC VALUE OF CULTIVATED LAND IN CHINA 期刊论文 OAI收割 CHINESE GEOGRAPHICAL SCIENCE, 2005, 卷号: 15, 期号: 3, 页码: 193-199 Wang Xiu-fen; Chen Bai-ming(陈百明); Bi Ji-ye 收藏 \| 浏览/下载：321/54 \| 提交时间：2011/05/27 cultivated land economic value scissors difference scissors difference adjustment P. R. China
	SCISSORS DIFFERENCE AND ITS IMPACTS ON ECONOMIC VALUE OF CULTIVATED LAND IN CHINA SCI/SSCI论文 OAI收割 2005 Wang X. F.; Chen B. M.; Bi J. Y. 收藏 \| 浏览/下载：25/0 \| 提交时间：2012/06/08 cultivated land economic value scissors difference scissors difference adjustment P. R. China