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Radiometric cross-calibration of the CBERS-02 CCD camera with the TERRA MODIS

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Science China(Technological Sciences) 2005年第S2期48卷 44-60页

作者： LI Xiaoying1,2,3, GU Xingfa1,3,4. MIN Xiangjun5, YU Tao1,3, FU Qiaoyan5, ZHANG Yong1,2,3 & LI Xiaowen1,3 1. State Key laboratory of Remote Sensing Science, Jointly Sponsored by the institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China 3. The Center for national Spaceborne demonstration, Beijing 100101, China 4. institut national de la recherche agronomique, climat sol environnement, 84.14.Avignon, France 5. China Center for Resource Satellite Data and Application, Beijing 100830, China 1. State Key laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University 100101 Beijing China 2. Graduate University of Chinese Academy of Sciences 100039 Beijing China 3. The Center for national Spaceborne demonstration 100101 Beijing China 4. institut national de la recherche agronomique Climat Sol Environnement 84914 Avignon France 5. China Center for Resource Satellite Data and Application 100830 Beijing China

For the application of the CCD camera, the most important payload on CBERS-02, the key is to provide long-term stable radiometric calibration coefficients. Although the vicarious calibration had been proved successful, it had its limitations such as test site requirement and unsuitable for historical data. Cross-calibration is one of the alternative methods, but it needs synchro surface spectrum to achieve spectral band matching factors. Our effort is to probe the influences on these factors. Simulations with a lot of surface spectrum showed that the factors changed with the viewing geometry, atmospheric condition and surface targets. However, simulating with the same viewing geometry and atmospheric condition, the spectral band matching factors of the same or similar surface targets’ spectrum acquired from different dates and different places would like to be consistent to each other within 1%―5%. Thus, the synchro measurement data can be substituted by the same or similar target from other source. Based on this method, using the MODIS as the reference, the cross-calibration was performed for CCD camera. The research demonstrated that the traditional method with single calibration site was inappropriate for CCD camera, since the offsets for its four spectral bands were not zeros. With four calibration sites, these offsets were obtained. And the camera was detected to degrade with dates based on four times of cross-calibrations.

关键词： CBERS-02 CCD camera cross-calibration the spectral band matching factors.

Absolute radiometric calibration of CBERS-02 IRMSS thermal band

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Science China(Technological Sciences) 2005年第S2期48卷 72-90页

作者： ZHANG Yong1,2,3, GU Xingfa1,3,4. YU Tao1,3, ZHANG Yuxiang5, CHEN Liangfu1,3, LI Xiaoying1,2,3, LI Xiaowen1,3 & HE Liming6 1. State Key laboratory of Remote Sensing Science, Jointly Sponsored by the institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China 3. The Center for national Spaceborne demonstration, Beijing 100101, China 4. institut national de la recherche agronomique, climat sol environnement, 84.14.Avignon, France 5. national Satellite Meteorological Center, Beijing 100081, China 6. State Environmental Protection Administration, Beijing 100029, China Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Beijing Normal Univ State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Chinese Acad Sci Grad Univ Beijing 100039 Peoples R China Ctr Natl Spaceborne demonstrat Beijing 100101 Peoples R China INRA F-84914 Avignon France Natl Satellite Meteorol Ctr Beijing 100081 Peoples R China State Environm Protect Adm Beijing 100029 Peoples R China

Based on the laboratory calibration before launch of CBERS-02 IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at lake Qinghai: water surface radiometric calibration test site of China on Aug. 17, 2004.are carried out in this research. When making onboard blackbody calibration of CBERS-02 IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at normal and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field experiments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02 IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through lake Qinghai and lake Taihu from August to december, 2004.to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02 IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53 (gain, unit: DN/W m?2sr?1μm?1) and 4..92 (offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

In flight MTF monitoring and compensation for CCD camera on CBERS-02

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Science China(Technological Sciences) 2005年第S2期48卷 29-43页

作者： GU Xingfa1,2,3, LI Xiaoying1,2,4. MIN Xiangjun5, YU Tao1,2, SUN Jijuan5, ZENG Yong1,2,4. XU Hua1,2 & GUO Ding2,6 1. State Key laboratory of Remote Sensing Science, Jointly Sponsored by the institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101, China 2. The Center for national Spaceborne demonstration, Beijing 100101, China 3. institut national de la {4. agronomique, climat sol environnement, 84.14.Avignon, France 4. Graduate University of Chinese Academy of Sciences, Beijing 100039, China 5. China Center for Resource Satellite Data and Application, Beijing 100830, China 6. University of Electronic Science and Technology of China, Chengdu 610054. China State Key laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University 100101 Beijing China The Center for national Spaceborne demonstration 100101 Beijing China institut national de la recherche agronomique Climat Sol Environnement 84914 Avignon France Graduate University of Chinese Academy of Sciences 100039 Beijing China China Center for Resource Satellite Data and Application 100830 Beijing China University of Electronic Science and Technology of China 610054 Chengdu China

In this article, the approach of simulating ideal tarp scene was proposed to determine the MTF for CCD camera on CBERS-02. The MTF acquired from this technique was compared to those from some common methods. MTFs achieved from different approaches were employed to compensate the CCD images based on three restoration algorithms: the iterative method, the Wiener filter and the modified inverse filter (MIF). The two-dimensional MTF was established with the value at frequency 0.5 for 4.° directional MTF as the value at its four corners. This article addressed the variations of the restored CCD images with different techniques of constructing two-dimensional MTF, restoring algorithms and determining the in-flight MTFs. Results showed images restored with the MTF determined from the technique of simulating ideal tarp scene represent the real scene best. And the restoration technique based on the MIF would produce better restored images than the other two techniques. This research also demonstrated that the two-dimensional MTF used for restoration should be interpolated under the control of the MTF for 4.° axis, rather than by multiplying the cross-orbit MTF with along-orbit MTF.

关键词： CBERS-02 CCD MTF the technique of simulating ideal tarp scene.

Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

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Science China(Technological Sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3, LI Xiaoying1,2,3, ZHANG Yong1,2,3, ZHAO Feng1,2,3, GU Xingfa1,3,4. ZHU Li1,2,3, WANG Pengxin5 & MIN Xiangjun6 1. State Key laboratory of Remote Sensing Science institute of Remote Sensing Application, CAS, Bei- jing 100101, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China 3. The Center for national Spaceborne demonstration, Beijing 100101, China 4. institut national de la recherche agronomique, climat sol environnement, 84.14.Avignon, France 5. College of Information and Electrical Engineering, China Agricultural University, Beijing 100083, China 6. China Center for Resource Satellite Data and Application, Beijing 100830, China 1. State Key laboratory of Remote Sensing Science Institute of Remote Sensing Application CAS 100101 Beijing China 2. The Center for national Spaceborne demonstration 100101 Beijing China 3. Graduate University of Chinese Academy of Sciences 100039 Beijing China 4. institut national de la recherche agronomique Climat Sol Environnent 84914 Avignon France 5. College of Information and Electrical Engineering China Agricultural University 100083 Beijing China 6. China Center for Resource Satellite Data and Application 100830 Beijing China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI laI.

Cold plumes trigger contamination of oceanic mantle wedges with continental crust-derived sediments:Evidence from chromitite zircon grains of eastern Cuban ophiolites

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Geoscience Frontiers 2018年第6期9卷 1921-1936页

作者： J.A.Proenza J.M.González-Jiménez A.Garcia-Casco E.Belousova W.L.Griffin C.Talavera Y.Rojas-Agramonte T.Aiglsperger D.Navarro-Ciurana N.Pujol-solà F.Gervilla S.Y.O’Reilly D.E.Jacob departament de Mineralogia Petrologia i Geologia AplicadaUniversitat de BarcelonaC/Martíi Franquès s/n08028BarcelonaSpain departamento de Mineralogía y Petrología Universidad de GranadaFacultad de CienciasFuentenueva s/n 18002GranadaSpain instituto Andaluz de Ciencias de la Tierra(CSIC-UGR) Avda.de las Palmeras 4E-18100ArmillaGranadaSpain ARC Centre of Excellence for Core to Crust Fluid Systems(CCFS) GEMOC National Key CentreDepartment of Earth and Planetary SciencesMacquarie UniversitySydneyNSW 2109Australia John de laeter Centre Curtin UniversityPerthWA 6102Australia Geocycles-Earth System Research Center Institut fur GeowissenschaftenJohannes Gutenberg-UniversitatBecherweg 21D-55099 MainzGermany departamento de Geociencias Universidad de los AndesBogotáColombia

The origin of zircon grains, and other exotic minerals of typical crustal origin, in mantle-hosted ophiolitic chromitites are hotly debated. We report a population of zircon grains with ages ranging from Cretaceous(99 Ma) to Neoarchean(2750 Ma), separated from massive chromitite bodies hosted in the mantle section of the supra-subduction(SSZ)-type Mayari-Baracoa Ophiolitic Belt in eastern Cuba. Most analyzed zircon grains(n = 20, 287 ± 3 Ma to 2750 ± 60 Ma) are older than the early Cretaceous age of the ophiolite body, show negativeε_(Hf)(t)(-26 to-0.6) and occasional inclusions of quartz, K-feldspar,biotite, and apatite that indicate derivation from a granitic continental crust. In contrast, 5 mainly rounded zircon grains(297±5 Ma to 2126±27 Ma) show positive εHf(t)(+0.7 to +13.5) and occasional apatite inclusions, suggesting their possible crystallization from melts derived from juvenile(mantle)sources. Interestingly, younger zircon grains are mainly euhedral to subhedral crystals, whereas older zircon grains are predominantly rounded grains. A comparison of the ages and Hf isotopic compositions of the zircon grains with those of nearby exposed crustal terranes suggest that chromitite zircon grains are similar to those reported from terranes of Mexico and northern South America. Hence, chromitite zircon grains are interpreted as sedimentary-derived xenocrystic grains that were delivered into the mantle wedge beneath the Greater Antilles intra-oceanic volcanic arc by metasomatic fluids/melts during subduction processes. Thus, continental crust recycling by subduction could explain all populations of old xenocrystic zircon in Cretaceous mantle-hosted chromitites from eastern Cuba *** integrate the results of this study with petrological-thermomechanical modeling and existing geodynamic models to propose that ancient zircon xenocrysts, with a wide spectrum of ages and Hf isotopic compositions, can be transferred to the mantle wedge above subducting slabs by

关键词： Zircon U-Pb geochronology Chromitites Cold plumes Ophiolites Cuba

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自由林网对农田地形的影响

生态学报 1981年第2期6卷 112-116页

作者：曹新孙姜凤岐雷启迪中国科学院林业土壤研究所

我国东北、华北和西北等风沙危害严重地区,长期以来,农民群众以防止风沙的机械作用为目的,自发地营造了许多不规整的小林网,这种小林网就是所谓的自由林网。一般是由2—3行树木构成的窄林带,带间距离多在100米以内。选用的树种以早柳为... 详细信息

我国东北、华北和西北等风沙危害严重地区,长期以来,农民群众以防止风沙的机械作用为目的,自发地营造了许多不规整的小林网,这种小林网就是所谓的自由林网。一般是由2—3行树木构成的窄林带,带间距离多在100米以内。选用的树种以早柳为主,间或也有杨树、榆树或其它的阔叶树种,由于自由林网能够较为迅速地起到保护农田。

关键词：林网林带高度积沙带农田农业用地地形地貌

The Giant Radio Array for Neutrino detection(GRAND):Science and design

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Science China(Physics,Mechanics & Astronomy) 2020年第1期Mechanics & Astronomy) .卷 5-47页

作者： Jaime álvarez-Mu?iz Rafael Alves Batista Aswathi Balagopal V. Julien Bolmont Mauricio Bustamante Washington Carvalho Jr. Didier Charrier Isma?l Cognard Valentin decoene Peter B.denton Sijbrand de Jong Krijn D.de Vries Ralph Engel Ke Fang Chad Finley Stefano Gabici Quan Bu Gou Jun Hua Gu Claire Guépin Hong Bo Hu Yan Huang Kumiko Kotera Sandra Le Coz Jean-Philippe Lenain Guo Liang Léü Olivier Martineau-Huynh Miguel Mostafá Fabrice Mottez Kohta Murase Valentin Niess Foteini Oikonomou Tanguy Pierog Xiang Li Qian Bo Qin Duan Ran Nicolas Renault-Tinacci Markus Roth Frank G.Schr ?der Fabian Schüssler Cyril Tasse Charles Timmerman Matías Tueros Xiang Ping Wu Philippe Zarka Andreas Zech B.Theodore Zhang Jian Li Zhang Yi Zhang Qian Zheng Anne Zilles departamento de Física de Partículas & instituto Galego de Física de Altas Enerxías Universidad de Santiago de Compostela instituto de Astronomia Geofísica e Ciências Atmosféricas Universidade de S?o Paulo department of Physics—Astrophysics University of Oxford DWB institute of Experimental Particle Physics (ETP) Karlsruhe Institute of Technology (KIT) laboratoire de Physique Nucléeaire et de Hautes Energies (LPNHE) Sorbonne Université Université Paris Diderot Sorbonne Paris Cité Niels Bohr International Academy and DARK Niels Bohr Institute Discovery Center Niels Bohr Institute Center for Cosmology and Astro Particle Physics (CCAPP) & department of Physics Ohio State University Universidade de Santiago de Compostela SUBATECH Institut Mines-Telecom Atlantique – CNRS/IN2P3 – Université de Nantes laboratoire de Physique et Chimie de l’environnement et de l’Espace LPC2E CNRS-Université d’Orléans Station de Radioastronomie de Nan?cay Observatoire de Paris Sorbonne Université UMR 7095 Institut d’Astrophysique de Paris institute for Mathematics Astrophysics and Particle Physics (IMAPP) Radboud Universiteit Nationaal Instituut voor Kernfysica en Hoge Energie Fysica (NIKHEF) IIHE/ELEM Vrije Universiteit Brussel institute for Nuclear Physics (IKP) Karlsruhe Institute of Technology (KIT) Einstein Fellow Stanford University department of Astronomy University of Maryland Joint Space-Science institute Oskar Klein Centre Stockholm University department of Physics Stockholm University Astro Particule et Cosmologie (APC) Université Paris Diderot CNRS/IN2P3 CEA/Irfu Observatoire de Paris institute of High Energy Physics Chinese Academy of Sciences national Astronomical Observatories Chinese Academy of Sciences School of Physical Science and Technology Xinjiang University Center for Particle and Gravitational Astrophysics Pennsylvania State University department of Physics Pennsylvania State University department of Astronomy & Astrophysics Pennsylvania State University LUTH Observatoire de Paris

The Giant Radio Array for Neutrino detection（GRAND） is a planned large-scale observatory of ultra-high-energy（UHE） cosmic particles, with energies exceeding 10～8 Ge V. Its goal is to solve the long-standing mystery of the origin of UHE cosmic rays. To do this, GRAND will detect an unprecedented number of UHE cosmic rays and search for the undiscovered UHE neutrinos and gamma rays associated to them with unmatched sensitivity. GRAND will use large arrays of antennas to detect the radio emission coming from extensive air showers initiated by UHE particles in the atmosphere. Its design is modular: 20 separate, independent sub-arrays, each of 10000 radio antennas deployed over 10000 km2. A staged construction plan will validate key detection techniques while achieving important science goals early. Here we present the science goals, detection strategy, preliminary design, performance goals, and construction plans for GRAND.

关键词： radio telescopes neutrinos in astronomical observations cosmic rays in astronomical observations radiowave radiation: sources galactic and extragalactic cosmic rays