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A Review on State-of-the-Art Power Line Inspection Techniques 期刊论文  OAI收割
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, 2020, 卷号: 69, 期号: 12, 页码: 9350-9365
作者:  
Yang, Lei;  Fan, Junfeng;  Liu, Yanhong;  Li, En;  Peng, Jinzhu
  |  收藏  |  浏览/下载:56/0  |  提交时间:2021/01/06
Imaging characters of the lung cancer phantoms under the simulative clinical condition performed with hard X-ray in-line holography 期刊论文  OAI收割
JOURNAL OF INSTRUMENTATION, 2013, 卷号: 8, 页码: C07002
作者:  
Zhang J(张杰);  Chen Y(陈雨);  Li G(黎刚);  姜晓明;Zhang, J;  Chen, Y
收藏  |  浏览/下载:20/0  |  提交时间:2016/04/08
Destriping method using lifting wavelet transform of remote sensing image (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
作者:  
He B.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
Based on the characteristic of striping noise in remote sensing images  a new destriping noise technique for the improved multi-threshold method using lifting wavelet transform applied to remote sensing imagery is presented in this letter. Have used the lifting wavelet decomposition algorithm  the thresholds are determined by corresponding wavelet coefficients in every scale. Remote sensing imagery is so large that the algorithm must be fast and effective. The lifting wavelet transform is easily realized and inexpensive in computer time and storage space compared with the traditional wavelet transform. We also compare the method with some traditional destriping methods both by visual inspection and by appropriate indexes of quality of the denoised images. From the comparison we can see that the adaptive threshold method can preserve the spectral characteristic of the images while effectively remove striping noise and it did better than the existed ones. 2010 IEEE.  
Mid-frequency surface error test with a Foucault apparatus (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, July 8, 2007 - July 12, 2007, Chengdu, China
作者:  
Li J.;  Li J.;  Xuan B.;  Li J.
收藏  |  浏览/下载:17/0  |  提交时间:2013/03/25
Testing of mid-frequency surface error is of the first importance for fast optics  especially for large aperture aspherics. Foucault test plays a dominant role for surface error inspection before the digital interferometer age  but it seems to have faded out these days because no quantitative results turn out. However  an interferometer with high resolution CCDs is either unavailable or unaccessible in the process of manufacture. As its advantages are realized and recognized for the second time  Foucault test is going back to the stage again. A new theory of calculating the contrast of the shadow pattern of Foucault test is put forward in this paper and some modifications are discussed upon the analyses of the limitation of traditional Foucault apparatus. A paraboloidal mirror was fabricated and tested by the modified Foucault apparatus whose effect has been proved to be great. The methods of controlling mid-frequency error are described in the other paper at this conference- "Multi-mode combine manufacturing technology for large aperture aspheric mirrors"1.  
Research on the nonuniformity correction of linear TDI CCD remote camera (EI CONFERENCE) 会议论文  OAI收割
Advanced Materials and Devices for Sensing and Imaging II, November 8, 2004 - November 10, 2004, Beijing, China
Ya-xia L.; Zhi-hang H.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
Many applications  such as industrial inspection and overhead reconnaissance benefit from line scanning architectures where time delay integration (TDI) significantly improves sensitivity[5]. Images with linear response have become the backbone of the imaging industry. But each pixel of the TDI CCD has unique light sensitivity characteristics. Because these characteristics and the lens of the optical system affect camera's linearization and its performance  they must be removed through calibration. The process by which a CCD image is calibrated is known as nonuniformity correction. This paper discusses several methods of nonuniformity correction[2]. The first is one-point correction technique  which requires only one calibration point. This approach is to shift each curve toward the nominal curve by subtracting the offset from or adding the offset to the average. The second is two-point correction technique  which requires two calibration points. Each point is rotated and aligned so that all the detectors have the same response under the same radiance. The third is multipoint correction. It is recommended that more calibration points be implemented at appropriate regions of the response curve. Depend on the linear photoelectric response of the TDI CCD  we use two-point calibration and the standard deviations for the images are given before and after the correction.