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	Analysis of the nonstationarity characteristics and future trends of flood extremes in the Dongting Lake Basin 期刊论文 OAI收割 JOURNAL OF HYDROLOGY-REGIONAL STUDIES, 2022, 卷号: 44, 页码: 19 作者: Gao, Yunpeng; Xia, Jun; Chen, Xingwei; Zou, Lei; Huang, Jie \| 收藏 \| 浏览/下载：26/0 \| 提交时间：2022/11/29 Flood extreme Nonstationarity Future trend GAMLSS model Dongting Lake Basin
	Spatio-Temporal Evolution, Future Trend and Phenology Regularity of Net Primary Productivity of Forests in Northeast China 期刊论文 OAI收割 REMOTE SENSING, 2020, 卷号: 12, 期号: 21, 页码: 22 作者: Wang, Chunli; Jiang, Qun'ou; Deng, Xiangzheng; Lv, Kexin; Zhang, Zhonghui \| 收藏 \| 浏览/下载：26/0 \| 提交时间：2021/03/16 Net Primary Productivity (NPP) phenology regularity future trend Northeast China
	Spatio-Temporal Evolution, Future Trend and Phenology Regularity of Net Primary Productivity of Forests in Northeast China 期刊论文 OAI收割 REMOTE SENSING, 2020, 卷号: 12, 期号: 21, 页码: 22 作者: Wang, Chunli; Jiang, Qun'ou; Deng, Xiangzheng; Lv, Kexin; Zhang, Zhonghui \| 收藏 \| 浏览/下载：8/0 \| 提交时间：2021/03/16 Net Primary Productivity (NPP) phenology regularity future trend Northeast China
	Amplitudes, rates, periodicities and causes of temperature variations in the past 2485 years and future trends over the central-eastern Tibetan Plateau 期刊论文 OAI收割 CHINESE SCIENCE BULLETIN, 2011, 卷号: 56, 期号: 28-29, 页码: 2986-2994 作者: An, ZS (An ZhiSheng)[1]; Liu, Y (Liu Yu)[1,2] \| 收藏 \| 浏览/下载：15/0 \| 提交时间：2018/12/19 Central-eastern Tibetan Plateau Temperature Amplitude Rate Periodicity Cause Future Trend
	Research on automatic Hartmann test of membrane mirror (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: Zhang P. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 Electrostatic membrane mirror is ultra-lightweight and easy to acquire a large diameter comparing with traditional optical elements so its development and usage is the trend of future large mirrors. In order to research the control method of the static stretching membrane mirror the surface configuration must be tested. However membrane mirror's shape is always changed by variable voltages on the electrodes and the optical properties of membrane materials using in our experiment are poor so it is difficult to test membrane mirror by interferometer and null compensator method. To solve this problem an automatic optical test procedure for membrane mirror is designed based on Hartmann screen method. The optical path includes point light source CCD camera splitter and diffuse transmittance screen. The spots' positions on the diffuse transmittance screen are pictured by CCD camera connected with computer and image segmentation and centroid solving is auto processed. The CCD camera's lens distortion is measured and fixing coefficients are given to eliminate the spots' positions recording error caused by lens distortion. To process the low sampling Hartmann test results Zernike polynomial fitting method is applied to smooth the wave front. So low frequency error of the membrane mirror can be measured then. Errors affecting the test accuracy are also analyzed in this paper. The method proposed in this paper provides a reference for surface shape detection in membrane mirror research. 2010 Copyright SPIE - The International Society for Optical Engineering.