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浏览/检索结果: 共14条，第1-10条 帮助

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Spatial Process Analysis of the Evolution of Farmland Landscape in China 期刊论文  OAI收割
ISPRS INTERNATIONAL JOURNAL OF GEO-INFORMATION, 2024, 卷号: 13, 期号: 3, 页码: 15
作者:  Fu, Yan;  Qi, Qingwen;  Jiang, Lili;  Zhao, Yapeng
  |  收藏  |  浏览/下载：27/0  |  提交时间：2024/05/06
Disturbance-level-dependent post-disturbance succession in a Eurasian steppe 期刊论文  OAI收割
SCIENCE CHINA-LIFE SCIENCES, 2022, 卷号: 65, 期号: 1, 页码: 142-150
作者:  Yang, Junjie;  Xu, Minjie;  Pang, Shuang;  Gao, Lili;  Zhang, Zijia
  |  收藏  |  浏览/下载：16/0  |  提交时间：2024/03/07
Disentangling Responses of the Subsurface Microbiome to Wetland Status and Implications for Indicating Ecosystem Functions 期刊论文  OAI收割
MICROORGANISMS, 2021, 卷号: 9, 期号: 2, 页码: -
作者:  Gao, Jie;  Liu, Miao;  Shi, Sixue;  Liu, Ying;  Duan, Yu
  |  收藏  |  浏览/下载：28/0  |  提交时间：2021/12/23
Effects of Salinity and Water Depth on Germination of Phragmites australis in Coastal Wetland of the Yellow River Delta 期刊论文  OAI收割
CLEAN-SOIL AIR WATER, 2012, 卷号: 40, 期号: 10, 页码: 1154-1158
作者:  Yu, Junbao;  Wang, Xuehong;  Ning, Kai;  Li, Yunzhao;  Wu, Huifeng
收藏  |  浏览/下载：28/0  |  提交时间：2013/03/08
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：52/0  |  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.  
Research on image restoration of Roll-Swing imaging seeker (EI CONFERENCE) 会议论文  OAI收割
3rd IEEE International Conference on Advanced Computer Control, ICACC 2011, January 18, 2011 - January 20, 2011, Harbin, China
作者:  Zhang H.;  Zhang H.
收藏  |  浏览/下载：35/0  |  提交时间：2013/03/25
To achieve a correct image receiving for Roll-Swing imaging seeker  the mechanism and imaging process is analyzed. The causes of image rotation are discussed. The influence of the frame encoders' precision on imaging de-rotation quality is analyzed. The Roll-Swing imaging seeker is designed for high-speed aerocraft  thus the received images are greatly degraded due to atmospheric turbulence. A new method of image restoration is proposed for turbulence-degraded images in this paper. The method is to get point spread function (PSF) based on the estimation of optical transfer function (OTF) according to the optical system design simulation. Finally  to obtain the restored image  constrained least squares filtering is used with the known PSF. The experiment results indicate that the new restoration method has a favorable effect to satisfy requirement of the automatic target recognition. 2011 IEEE.  
Design and image restoration research of a cubic-phase-plate system (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, April 26, 2010 - April 29, 2010, Dalian, China
作者:  Zhang J.;  Zhang J.;  Zhang J.;  Shi G.;  Zhang X.
收藏  |  浏览/下载：32/0  |  提交时间：2013/03/25
Wave-front coding technology is a novel jointly optical and digital imaging technology which can greatly extend the depth of focus of optical systems. The image restoration process is an important part of wave-front coding technology. Using wave-front coding makes the modulation transfer function(MTF) values of the optical systems change little over a range of several times the depth of focus  which means the system MTF is quite insensitive to defocus  and there is no zero in the passband. So we can design a single filter for the restoration of images in different defocus positions. However  it's hard to avoid noise during image acquisition and transmission processes. These noises will be amplified in the image restoration  especially in the high frequency part when the MTF drop is relatively low. The restoration process significantly reduces the system signal to noise ratio this way. Aimed at the problem of noise amplification  a new algorithm was proposed which incorporated wavelet denoising into the iterative steps of Lucy-Richardson algorithm. Better restoration results were obtained through the new algorithm  effectively solving the noise amplification problem of original LR algorithm. Two sets of identical triplet imaging systems were designed  in one of which the cubic-phase-plate was added. Imaging experiments of the manufactured systems were carried  and the images of a traditional system and a wave-front coded system before and after decoding were compared. The results show that the designed wave-front coded system can extend the depth of focus by 40 times compared with the traditional system while maintaining the light flux and the image plane resolution. 2010 Copyright SPIE - The International Society for Optical Engineering.  
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：44/0  |  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.  
The ecological characteristics of the riparian vegetation affected by river overflowing disturbance in the lower Tarim river 期刊论文  OAI收割
Environmental Geology, 2009, 卷号: 58, 期号: 8, 页码: 1749-1755
Xu; Ye; Li; Hailiang1; Mao2; Jimei1
收藏  |  浏览/下载：32/0  |  提交时间：2011/08/19
Vegetation and soil properties in restored wetlands near Lake Taihu, China 期刊论文  OAI收割
HYDROBIOLOGIA, 2007, 卷号: 581, 页码: 151-159
Lu, Jinwei; Wang, Hongjun; Wang, Weidong; Yin, Chengqing
收藏  |  浏览/下载：33/0  |  提交时间：2015/09/10