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浏览/检索结果: 共8条，第1-8条 帮助

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Development and validation of the Landsat-8 surface reflectance products using a MODIS-based per-pixel atmospheric correction method 期刊论文  OAI收割
International Journal of Remote Sensing, 2016, 卷号: 37, 期号: 6, 页码: 1291-1314
作者:  Wang, Yingjie;  Liu, Liangyun;  Hu, Yong;  Li, Donghui;  Li, Zhengqiang
收藏  |  浏览/下载：23/0  |  提交时间：2017/04/24
Uncertainty analysis of terrestrial net primary productivity and net biome productivity in China during 1901-2005 期刊论文  OAI收割
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES, 2016, 卷号: 121, 期号: 5, 页码: 1372-1393
作者:  Shao, Junjiong;  Zhou, Xuhui;  Luo, Yiqi;  Zhang, Guodong;  Yan, Wei
收藏  |  浏览/下载：86/0  |  提交时间：2017/04/24
Test of an off-axis asphere by subaperture stitching interferometry (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  Zheng L.-G.;  Zhang X.-J.;  Zhang Z.-Y.;  Zhang Z.-Y.;  Deng W.-J.
收藏  |  浏览/下载：71/0  |  提交时间：2013/03/25
A new method combined subaperture stitching with interferometry(SSI) is introduced. It can test large and off-axis aspheric surfaces without the aid of other null optics. In this paper the basic principle and theory of the technique are analyzed. The synthetical optimization stitching model and effective stitching algorithm are established based on homogeneous coordinates transformation and simultaneous least-squares method. The software of SSI is devised and the prototype for testing of large aspheres by SSI is designed and developed. An off-axis asphere with the aperture of 376mm188mm is tested by this method. For comparison and validation  and the difference of PV and RMS error between them is 0.047 e and 0.006 e  the asphere is also tested by null compensation.The synthesized surface profile is consistent to that ofthe entire surface from null test  respectively. So it provides another quantitative measurement for testing large aspheric surfaces and off-axis aspheres besides null-compensation. 2009 SPIE.  
Assessment of surface roughness by use of soft x-ray scattering (EI CONFERENCE) 会议论文  OAI收割
Soft X-Ray Lasers and Applications VIII, August 4, 2009 - August 6, 2009, San Diego, CA, United states
Yan-li M.; Yong-gang W.; Shu-yan C.; Bo C.
收藏  |  浏览/下载：43/0  |  提交时间：2013/03/25
A soft x-ray reflectometer with laser produced plasma source has been designed  which can work from wavelength 8nm to 30 nm and has high performance. Using the soft x-ray reflectometer above  the scattering light distribution of silicon and zerodur mirrors which have super-smooth surfaces could be measured at different incidence angle and different wavelength. The measurement when the incidence angle is 2 degree and the wavelength is 1 lnm has been given in this paper. A surface scattering theory of soft x-ray grazing incidence optics based on linear system theory and an inverse scattering mathematical model is introduced. The vector scattering theory of soft x-ray scattering also is stated in detail. The scattering data are analyzed by both the methods above respectively to give information about the surface profiles. On the other hand  both the two samples are measured by WYKO surface profiler  and the surface roughness of the silicon and zerodur mirror is 1.3 nm and 1.5nm respectively. The calculated results are in quantitative agreement with those measured by WYKO surface profiler  which indicates that soft x-ray scattering is a very useful tool for the evaluation of highly polished surfaces. But there still some difference among the results of different theory and WYKO  and the possible reasons of such difference have been discussed in detail. 2009 SPIE.  
A new geospatial data model to facilitate geographic data mining and knowledge discovery 会议论文  OAI收割
2008 IEEE International Conference on Systems, Man and Cybernetics, SMC, Singapore, Singapore, 2008
Wang; Tao1; Chen; Xi1; Bao; An-Ming1; Wei-Sheng1
收藏  |  浏览/下载：42/0  |  提交时间：2011/08/23
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：30/0  |  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.  
The application study on building materials with computer color quantification system (EI CONFERENCE) 会议论文  OAI收割
ICO20: Illumination, Radiation, and Color Technologies, August 21, 2005 - August 26, 2005, Changchun, China
作者:  Yu H.;  Li Z.;  Li Z.
收藏  |  浏览/下载：38/0  |  提交时间：2013/03/25
The first impression of any building to a person is its exterior and decoration  therefore  at the same time  and therefore the quality of decoration project shows the more important position in building project. A lot of projects produce quality problem because of the material color difference  how to grasp and control the color change of building materials  the color difference problem laying stone materials is also studied in this paper  which exists universally at the common project  and carry out color quantification  and the solution scheme has been given using this system.  and is often found at the high-grade decoration  it has the very important meaning. According to the color theory  a computer vision system used in color quantification measurement is established  the standard illuminant A is selected as the light source. In order to realize the standardization of color evaluation  the mutual conversion between RGB and XYZ color space is studied  which is realized by the BP network. According to the colorimetry theory  the computer program is compiled in order to establish the software system  and realize the color quantitative appraisement in whole color gamut. LCH model is used at quantifying the color of building materials  and L*a*V model is used at comparing the color change. If the wooden floor is selected and laid improperly during family fitment  it is easy to present "flower face". The color also arises greater discrepancy using the laths of same tree. We can give the laying scheme using the color quantification system  
Analysis of dynamic factor of debris landslide by mans of the model of quantitative theory - using the Xintan landslide, China, as an exmple 期刊论文  OAI收割
ENVIRONMENTAL GEOLOGY, 2005, 卷号: 48, 期号: 6, 页码: 676-681
作者:  He, KQ;  Yang, JB;  Wang, SJ
  |  收藏  |  浏览/下载：32/0  |  提交时间：2018/09/26