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Automatic Stitching Method for Chang＇E-2 CCD Images of the Moon

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Journal of Earth Science 2017年第1期28卷 168-179页

作者： Zhi Li Mengjie Ye Zhanchuan Cai zesheng tang Faculty of Information Technology Macao University of Science and Technology Macao China School of information Technology Beijing Normal University Zhuhai 519087 China School of Information Technology Tsinghua University Beijing 100084 China

The lunar map is a product of primary scientific objectives of lunar exploration. Aiming at the characteristics of the Chang＇E-2 CCD data, an automatic stitching method used for 2C level CCD data from Chang＇E-2 lunar mission is proposed. Combining with the image registration technique and the characteristics of Chang＇E CCD images, the fast method proposed not only can overcome the contradiction of the high spatial resolution of the CCD images and the low positioning accuracy of the location coordinates, but also can speed up the processing and minimize the utilization of human resources to produce lunar mosaic map. Meanwhile, a new lunar map from 70oN to 70oS with spatial resolution of less than 10 m has been completed by the proposed method. Its average relative location accuracy of the adjacent orbits CCD image data is less than 3 pixels.

关键词： Chang'E-2 CCD data processing automatic image stitching.

Lunar potassium distribution:Results from Chang'E-1 gamma ray spectrometer

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Science China(Physics,Mechanics & Astronomy) 2011年第11期54卷 2083-2090页

作者： ZHU Meng-Hua MA Tao CHANG Jin tang zesheng IP Wing-Huen XU AoAo Space Exploration Laboratory Macao University of Science and Technology Avenida Wai Long Taipa Macao China Purple Mountain Observatory Chinese Academy of Sciences 2 West Beijing Road Nanjing 210008 China

The global map of potassium is represented in this paper from Chang'E-1 (CE-1) Gamma-ray Spectrometer (CGRS) for its one-year *** a linear relationship between net count rate and its abundance,the average potassium abundance of individual landing sites is used as ground-truth for the calibration to derive the global map of absolute *** CGRS spectra have a lower signal-to-noise ratio,the translated map still keeps relative *** calculated from Apollo,Lunar Prospector,and Kaguya,global potassium map from CGRS shows high concentrations on the lunar nearside and secondary concentrations located in the South Pole-Aitken (SPA) basin on the *** comparison with Lunar Prospector potassium map shows a good correlation,though abundances on the highlands of the farside are much lower than that of Lunar *** the footprint of CGRS measurements is larger than the sampling radius of each landing site,the calibrated map shows a larger variation range of the scale than that of Lunar Prospector,which was derived using theoretical calculation;namely,the calibrated map has higher values in the areas with high concentration while having lower values for the areas with lower ***,the derived potassium map is more consistent with the lunar sample data than that of Lunar Prospector.

关键词： Chang'E-1 gamma-ray spectrometer potassium distribution empirical calibration

Global absorption center map of the mafic minerals on the Moon as viewed by CE-1 IIM data

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Science China(Physics,Mechanics & Astronomy) 2010年第12期53卷 2160-2171页

作者： WU YunZhao ZHANG Xia YAN BoKun GAN FuPing tang zesheng XU AoAo ZHENG YongChun ZOU YongLiao School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093China Institute of Remote Sensing Applications Chinese Academy of SciencesBeijing 100101China Institute for Remote Sensing Method China Aero Geophysical Survey and Remote Sensing Center for Land and ResourcesBeijing 100083China Collaborative Research Laboratory on Lunar and Planetary Exploration Macao University of Science and TechnologyTaipaMacaoChina National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

Determining the global distribution of minerals on the Moon has been an important goal of lunar science. Hyperspectral remote sensing is an important approach to acquiring minerals on the Moon on the global scale. The wavelength of the absorption band center is the key parameter for identifying minerals with reflectance spectra as well as remote sensing data. The global absorption center map of the mafic minerals of the Moon was produced for the first time with the Chang’E-1 IIM data. This map shows the global distribution of mafic minerals such as orthopyroxenes, clinopyroxenes, and olivine and even plagioclase feldspar of the Moon. The validation for some representative areas indicates that the global map is reliable and even more detailed than the results derived from Clementine-data. Moreover, our method is insensitive to the topography and viewing and illumination geometries. The global absorption band center map not only contributes to the lunar science research, but also has other implications to be further studied. Moreover, the preprocessing methods such as calibration and correction introduced in this study can be useful in other research with IIM data.

关键词： Chang’E-1 IIM absorption band center calibration Moon

Absolute calibration of the Chang'E-1 IIM camera and its preliminary application

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Science China(Physics,Mechanics & Astronomy) 2009年第10期52卷 1842-1848页

作者： WU YunZhao XU XiSheng XIE ZhiDong tang zesheng Collaborative Research Laboratory on Lunar and Planetary Exploration Macao University of Science and TechnologyTaipaMa-caoChina School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093China Department of Earth Sciences Nanjing UniversityNanjing 210093China

The interference imaging spectroradiometer (IIM) onboard the first lunar satellite of China "Chang'E-1" can now provide approximately global high spectral and spatial resolution reflectance spectra of the Moon. It is the essential instrument with which to accomplish one of the four missions of the first lunar satellite of China. As the current data provided by the Lunar Exploration Program Center and National Astronomical Observatories (NAOC) are not reflectance and the sensor response is inhomogeneous in the line direction,users can not use the current data directly. Moreover,due to the narrow band range,IIM data cannot cover the absorption peak of the mafic minerals of the Moon completely,which limits its ability for identifying minerals. The main objective of this study is to describe the methods for absolute calibration,correction and acquiring the absorption center of minerals for IIM data. The results from our study show that in the space domain the sensor response decreases toward the left,and in the spectral domain the response of the longer bands is more inhomogeneous than that of the shorter bands. After the calibration and correction,the reflectance of IIM matches the earth-based telescopic spectra well,which suggests the possible use of the processed data in the geological research. A high correlation was found between the absorption center and the wavelength at which the first derivative equals 0,i.e.,the so-called Stagnation Point in the mathematical sense. In the end,we show a preliminary applied study of the two craters with diameter larger than 35 km using the calibrated data. The spectra of IIM data show that the lunar crust has compositional diversity within the km scale. Pure anorthosite may be found on the wall and floor of the Aristarchus crater with the map of absorption center,which indicates that anorthosite is ubiquitously present within the lunar crust. IIM,with its capacity to acquire lunar composition at the regional and global scale,wil

关键词： Chang’E-1 IIM calibration radiometric Correction the Moon

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On the Curing Theory and Scaling Study -The Polycondenzation of Aa-Bb Type

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Chemical Research in Chinese Universities 1988年第3期 70-79页

作者： tang Auchin, Li zesheng, Sun Chiachung tang Xinyi(Institute of Theoretical Chemistry and Chemistry Department, JilinUniversity, Changchun)

In this paper, a systematic way is proposed to treat the poly condenzation reaction with two species of monomers A and B having a-and b-functionalities, respectively. The polycondenzation reaction is considered as a whole to approach gel point which can be equivalently represented by three different kinds of forms. Furthermore, by means of a reasonable way without Stirling's approximation, the asymptopic form of the equilibrium number distribution characterized by A-B type near the gel point is obtained to reach a generalized scaling law.

关键词： Polycondenzation Stirling’s approximation scaling law.

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基于克里金插值法的图像修复

计算机辅助设计与图形学学报 2013年第9期25卷 1281-1287页

作者：蔡占川姚菲菲唐泽圣澳门科技大学资讯科技学院

为了提高油画图像修复的效果,将克里金插值法应用于数字彩色油画图像修复中,把图像的颜色值看作规则采样点上的高度场,将二维图像修复问题转化为空间位置点的插值重建问题.实验结果表明,采用文中方法进行油画图像修复优于已有方法,能正... 详细信息

为了提高油画图像修复的效果,将克里金插值法应用于数字彩色油画图像修复中,把图像的颜色值看作规则采样点上的高度场,将二维图像修复问题转化为空间位置点的插值重建问题.实验结果表明,采用文中方法进行油画图像修复优于已有方法,能正确、稳定地处理各种破损区域,并获得良好的修复效果.

关键词：克里金算法彩色油画图像图像修复

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复杂环境光照下的半透明材质恢复算法

计算机辅助设计与图形学学报 2006年第5期18卷 638-643页

作者：卜海亮孙延奎唐泽圣清华大学计算机科学与技术系北京100084

针对半透明材质的特性,将折射率和BRTDF模型同时引入绘制过程,给出一套有效的求解复杂环境光照下半透明物体参数的算法.通过分析各参数间的相互关系和作用,依次估计半透明材质的颜色、折射率、透射系数、漫反射系数、镜面反射系数和表... 详细信息

针对半透明材质的特性,将折射率和BRTDF模型同时引入绘制过程,给出一套有效的求解复杂环境光照下半透明物体参数的算法.通过分析各参数间的相互关系和作用,依次估计半透明材质的颜色、折射率、透射系数、漫反射系数、镜面反射系数和表面粗糙度系数,然后将这些参数值作为初值重复上述计算过程,利用这种递归的方法逐次求精各参数.实验表明,该算法在少数几次递归后能够高精度地恢复半透明材质参数,而且这些恢复的参数可有效地用于新场景的绘制.

关键词：半透明物体材质恢复折射率 BRTDF模型模拟退火算法

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嫦娥一号高能粒子分布数据的可视化

计算机辅助设计与图形学学报 2011年第4期23卷 682-688页

作者：毛凯憨孙延奎张田唐泽圣清华大学计算机科学与技术系北京100084 澳门科技大学资讯科技学院澳门

针对大规模嫦娥一号高能粒子数据,提出采用可视化分析其数据分布的一套方法.利用各时刻获取的粒子通量来图示高能粒子通量随时间的变化情况;并将一段时间内粒子通量分成若干区间,利用直方图显示不同通量范围内粒子数的统计分布;针对月... 详细信息

针对大规模嫦娥一号高能粒子数据,提出采用可视化分析其数据分布的一套方法.利用各时刻获取的粒子通量来图示高能粒子通量随时间的变化情况;并将一段时间内粒子通量分成若干区间,利用直方图显示不同通量范围内粒子数的统计分布;针对月表各点粒子通量所处的不同范围,给出月表不同通量区间内粒子分布的三维显示;基于月表各投影网格对应的平均粒子通量,给出月表平均通量分布的三维显示;通过引入月地日夹角参数,可视化随月地日夹角变化的通量分布.基于文中方法设计并实现一个高能粒子可视化辅助分析系统,对不同月份、不同种类的高能粒子数据进行快速浏览和分析,大大提高了对高能粒子分布数据的分析效率.

关键词：可视化嫦娥一号高能粒子

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基于纹理硬件的大规模体数据快速绘制算法

清华大学学报（自然科学版） 2000年第1期40卷 72-75页

作者：童欣唐泽圣许忠信清华大学计算机科学与技术系 cad中心北京100084

针对大规模的体数据 ,有限的硬件纹理内存将大大降低算法的有效性 ,提出了一个新算法用于加速基于纹理硬件的大规模体数据的体绘制。基于一个新的 4级体数据装入流水线 ,算法在绘制前快速有效的对体数据进行预处理后 ,只将对最终结果图... 详细信息

针对大规模的体数据 ,有限的硬件纹理内存将大大降低算法的有效性 ,提出了一个新算法用于加速基于纹理硬件的大规模体数据的体绘制。基于一个新的 4级体数据装入流水线 ,算法在绘制前快速有效的对体数据进行预处理后 ,只将对最终结果图像有贡献的体元装入纹理内存并用于绘制 ,从而有效的降低了系统负载。同时 ,提出的算法支持对原始体数据分类阈值的交互修改与分类结果的快速预处理与交互显示。实验显示 ,与原始的基于纹理硬件的体绘制方法比较 ,本文提出的算法节省了 40 %到 6 0

关键词：体绘制可视化纹理硬件体数据绘制算法