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	光学卫星相机在轨调制传递函数检测方法期刊论文 OAI收割光学学报, 2020, 卷号: 40 作者: 徐伟伟; 张黎明; 杨宝云; 王戟翔 \| 收藏 \| 浏览/下载：11/0 \| 提交时间：2021/03/15 remote sensing modulation transfer function point source method square wave method knife-edge method 遥感调制传递函数点源法方波法刃边法
	A method of accurately determining temperature of cold atomic cloud in atomic fountain 期刊论文 OAI收割 ACTA PHYSICA SINICA, 2019, 卷号: 68, 期号: 19, 页码: 6 作者: Shi Jun-Ru; Wang Xin-Liang; Guan Yong; Ruan Jun; Liu Dan-Dan \| 收藏 \| 浏览/下载：19/0 \| 提交时间：2021/11/29 knife-edge method cold atomic cloud Gaussian radius cold atomic cloud's temperature
	一种精确测量原子喷泉冷原子团温度的方法期刊论文 OAI收割物理学报, 2019, 卷号: 68, 期号: 19 作者: 施俊如; 王心亮; 管勇; 阮军; 刘丹丹 \| 收藏 \| 浏览/下载：13/0 \| 提交时间：2020/09/02 knife-edge method cold atomic cloud Gaussian radius cold atomic cloud's temperature 刀口法冷原子团高斯半径冷原子团温度
	Space camera dynamic image quality measurement and evaluation (EI CONFERENCE) 会议论文 OAI收割 3rd International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2011, January 6, 2011 - January 7, 2011, Shanghai, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 By using analysis of the infinity image of the space camera we intend to obtain the curve of the dynamic modulation transfer function. We extract the pixel gray values at the image edge which distribute as a knife-edge function and make differential calculation and Fourier transformation of it and then we can obtain the dynamic MTF curve of the optical system. The value of the curve at the Nyquist frequency is the most important parameter that reflects the image quality. We add push-scanning imaging and environmental effects to the static MTF of space camera and compare the MTF value with the dynamic MTF at Nyquist frequency. The comparison result can help us verify the accuracy of the calculating results and the feasibility of our method. (2011) Trans Tech Publications.
	Adaptive Wiener filtering with Gaussian fitted point spread function in image restoration (EI CONFERENCE) 会议论文 OAI收割 2011 IEEE 2nd International Conference on Software Engineering and Service Science, ICSESS 2011, July 15, 2011 - July 17, 2011, Beijing, China 作者: Yang L.; Zhang X.; Zhang X.; Zhang X.; Yang L. 收藏 \| 浏览/下载：41/0 \| 提交时间：2013/03/25 In the imaging process of the space remote sensing camera there was degradation phenomenon in the acquired images. In order to reduce the image blur caused by the degradation the remote sensing images were restored to give prominence to the characteristic objects in the images. First the frequency-domain notch filter was adopted to remove strip noises in the images. Then using the ground characters with the knife-edge shape in the images the point spread function of the imaging system was estimated. In order to improve the accuracy the estimated point spread function was corrected with Gaussian fitting method. Finally the images were restored using the adaptive Wiener filtering with the fitted point spread function. Experimental results of the real remote sensing images showed that almost all strip noises in the images were eliminated. After the denoised images were restored its variance and its gray mean gradient increased also its laplacian gradient increased. Restoration with Gaussian fitted point spread function is beneficial to interpreting and analyzing the remote sensing images. After restoration the blur phenomenon of the images is reduced. The characters are highlighted and the visual effect of the images is clearer. 2011 IEEE.
	Remote sensing image restoration using estimated point spread function (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Information, Networking and Automation, ICINA 2010, October 17, 2010 - October 19, 2010, Kunming, China 作者: Yang L.; Yang L. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 In order to reduce image blur caused by the degradation phenomenon in the imaging process the acquired images of the space remote sensing camera are restored. First the frequency-domain notch filter is adopted to remove strip noises in the images. Then degradation function which is referred to as the point spread function (PSF) of the imaging system is estimated using the knife-edge method. To improve the accuracy of the estimation the estimated PSF is adjusted with Gaussian fitting. Finally the images are restored by Wiener filtering with the fitted PSF. The restoration results of the remote sensing images show that almost all strip noises are eliminated by the notch filter. After denoising and restoration the variance of the remote sensing image worked with in this paper increases 30.979 and the gray mean gradient increases 3.312. Due to Gaussian fitting the accuracy of the PSF estimation is heightened. Image restoration with the final PSF is benefit to interpreting and analyzing the remote sensing images. After restoration the contrasts of the restored images are increased and the visual effects become clearer. 2010 IEEE.
	On orbit MTF measurement of remote sensing camera based on wavelet transform (EI CONFERENCE) 会议论文 OAI收割 ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China 作者: Wang X.; Wang X.; Wang X. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 High resolution remote sensing images are often applied in many research fields. But there are less research on images quality for an orbit remote sensing camera. The magnitude of the OTF as the modulation transfer function (MTF) is a measure of the 2-D spatial frequency response of the remote sensing camera. In this paper knife-edge technique based on quadratic spline wavelet fast transform algorithm is proposed and applied to generate MTF with a greatly high resolution in horizontal or vertical direction. The result has fully demonstrate the potential applicability and good property of the method to estimate MTF for remote sensing camera.