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Free Radicals in Organic Matter for Thermal History Reconstruction of Carbonate Succession

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Acta Geologica Sinica(English Edition) 2007年第4期81卷 605-613页

作者： QIU Nansheng LI Huili JIN Zhijun and ZHU Yinkang 1 State Key Laboratory of Petroleum resource and Prospecting,China University of Petroleum,beijing 10224. 2 Basin and Reservoir Research {3.,China University of Petroleum,beijing 10224. 3.Institute of Petroleum Exploration and Development,SINOPEC,beijing 100083 State Key Laboratory of Petroleum resource and Prospecting China Universityof Petroleum Beijing 102249

Geothermometer is one of the most useful methods to reconstruct the thermal history of sedimentary basins. This paper introduces the application of free radicals concentration of organic matter as a thermal indicator in the thermal history reconstruction of carbonate succession, based on anhydrous thermal simulation results of type I and H1 kerogen. A series of free radicals data are obtained under thermal simulation of different heating temperatures and times, and quantitative modds between free radical concentration （Ng） of organic matter and time-temperature index （TTI） for types I and type H1 kerogen are also obtained. This *** relation was used to model the Ordovician thermal gradients of Well TZ12 in the Tarim Basin. The modeling result is corresponding to the results obtained by apatite fission track data and published data. This new method of thermal history reconstruction will be benefit to the hydrocarbon generation and accumulation study and {4. assessment of carbonate succession.

关键词： carbonate succession geothermometer free radicals of organic matter apatite fission track thermal history

Ocean color products retrieval and validation around China coast with MODIS

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Acta Oceanologica Sinica 2010年第4期29卷 21-27页

作者： SUN Lingt GUO Maohua WANG Xiaomei Key Laboratory of Radiometric Calibration and Validation for Environmental satellites China Meteorological Administration （LRCVES/CMA） National Satellite Meteorological Center China Meteorological Administration Beijing 100081 China National satellite Ocean application Service State Oceanic Administration Beijing 100081 China

Waters along China coast are very turbid with high concentrations of suspended sediment nearly all the time,especially at the Hangzhou Bay,the Changjiang （Yangtze） River Estuary and the shoal along Jiangsu *** these turbid and optically complex waters,the standard MODIS ocean color products tend to have invalid *** the water-leaving radiances in the near-infrared （NIR） are significant resulting from the strong scattering of suspended particles,the standard MODIS atmospheric correction algorithm often gets no results or produces significant *** because of the complex water optical properties,the OC3.model used in the standard MODIS data processing tends to get extremely high chlorophyll-a （Chl-a） *** this paper,we present an atmospheric correction approach using MODIS short wave infrared （SWIR） bands based on the fact that water-leaving radiances are negligible in the SWIR region because of the extreme strong absorption of water even in turbid waters.A regional Chl-a concentration estimation model is also constructed for MODIS from in situ *** algorithms are applied to MODIS Aqua data processing in the China coastal *** situ data collected in the Yellow Sea and the East China Sea in spring and autumn,2003.are used to validate the *** good results have been *** is noted that water-leaving reflectance in the NIR bands are significant in waters along the China coast with high sediment *** {3. derived and in-situ reflectance spectra can match in the turbid waters along China coast,and there is relatively good linear relationship between {3. derived and in-situ *** RMSE value of Rrs（λ） is 0.003. sr ？1 for all the nine ocean color bands （4.2 to 869 nm）.The {3.-derived Chl-a value is in the reasonable range and the root mean square percentage difference is 4..1%.

关键词： ocean color atmospheric correction chlorophyll-a MODIS China coastal region validation

application of Compass Ionospheric Model in GNSS Positioning

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Application of Compass Ionospheric Model in GNSS Positioning

第三届中国卫星导航学术年会

作者： Wu XiaoLi1Hu XiaoGong2 .Wang Gang1*Zhong HuiJuan3.Tang ChengPan21. beijing Global Information center of application and Exploration, beijing 100094. China 2. Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 20003., China 3. China Defense Science Technology Information center, beijing 10014., China

As an important component of a GNSS navigation message, ionospheric delay model parameters are broadcasted for single-frequency users to improve their positioning accuracy. GPS provides daily Klobuchar ionospheric model parameters based on geomagnetic reference frame, while the regional satellite navigation system of Compass broadcasts an eight-parameter ionospheric model generated by processing real data from continuous monitoring stations, which is updated every 2 hours. To evaluate model performance, model predictions are compared against real ionosphere measurements, along with positioning accuracy comparisons. Real data analysis indicates that the Compass ionospheric model provides higher correction precision in middle-latitude regions, but relatively lower correction precision for low-latitude regions where ionosphere possesses much more variability. Thanks to the constellation design of Compass, ionospheric model errors for some receivers manifest a common bias for in-coming GNSS signals from different satellites. Consequently, ionospheric model errors are somehow translated into the receivers’ clock error estimation, while have less influence on the positioning. Given that the Chinese global navigation system will still rely on a domestic continuous monitoring network to provide global ionosphere correction service, the applicability of the ionospheric model in regions beyond China’s mainland is studied by applying the regional model to single-frequency positioning experiments of GPS. Real data analysis shows that in the northern hemisphere areas including Asia, Europe and North America, compared with the GPS single-frequency positioning using Klobuchar model for ionospheric delay corrections, the three-dimension position accuracy is improved by 7.8% 3..3. by using the Compass model. But the positioning accuracy in the southern hemisphere is degraded by 9.5%3.5% due to the lack of monitoring stations there.

关键词： ionospheric model regional satellite navigation system model error positioning error

Chinese HJ-1A/B satellites and data characteristics

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中国科学：地球科学英文版 2010年第S1期53卷 51-57页

作者： WANG Qiao1,WU ChuanQing1,LI Qing1 & LI JunSheng2 1 satellite Environment center,Ministry of Environmental Protection,beijing 100029,China 2 center for Earth Observation and Digital Earth,Chinese Academy of Sciences,beijing 100190,China 1. satellite Environment center Ministry of Environmental Protection Beijing 100029 China2. Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100190 China

From the viewpoint of environmental remote-sensing applications,this article explains the overall technical characteristics of the Chinese HJ-1A and HJ-1B *** also investigates the spectral characteristics and potential applications of charge-coupled devices,and the infrared and hyperspectral data obtained by the *** of applications,such as the remote-sensing monitoring of algal bloom in Taihu Lake,straw burning in southern China,and aerosol optical depth in the area around Bohai sea are *** examples illustrate the application characteristics of the HJ-1A and HJ-1B satellite data.

关键词： HJ-1A/B application remote sensing characteristics

Remote sensing application system for water environments developed for Environment satellite 1

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中国科学：地球科学英文版 2010年第S1期53卷 45-50页

作者： WU ChuanQing1,WANG Qiao1,ZHANG YongJun1,LI JunSheng2,WU YuanFeng2,ZHU Li1 & YAO YanJuan1 1 satellite Environment center,Ministry of Environmental Protection,beijing 100029,China 2 center for Earth Observation and Digital Earth,Chinese Academy of Sciences,beijing 100190,China 1. satellite Environment center Ministry of Environmental Protection Beijing 100029 China2. Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100190 China

Remote sensing data collected by the Environment satellite I are characterized by high temporal resolution,high spectral resolution and mid-high spatial *** designed the Remote Sensing application System for Water Environments(RSASWE) to create an integrated platform for remote sensing data processing,parameter information extraction and thematic mapping using both remote sensing and GIS *** system provides support for regional water environmental monitoring,and prediction and warning of water *** to process and apply data collected by Environment satellite I,this system has automated procedures including clipping,observation geometry computation,radiometric calibration,6S atmospheric correction and water quality parameter *** consists of six subsystems:remote sensing image processing,basic parameter inversion,water environment remote sensing thematic outputs,application outputs,automated water environment outputs and a non-point source pollution monitoring *** present RSASWE plays an important role in operations at the satellite Environment center.

关键词： water environment Remote Sensing application System Environment satellite 1

application of the HY-1 satellite to sea ice monitoring and forecasting

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Acta Oceanologica Sinica 2004年第2期23卷 251-266页

作者： LUOYawei WUHuiding ZHANGYunfei SUNCongrong LIUYu DepartmentofEnvironmentalSciences PekingUniversityBeijing100871China NationalMarineEnvironmentForecastingcenter Beijing100081China NationalsatellitesOceanicapplicationService Beijing100081China

The HY-1A satellite is the first oceanic satellite of China. During the winter of 2002-2003. the data of the HY-1A were applied to the sea ice monitoring and forecasting for the Bohai Sea of China for the first time. The sea ice retrieval system of the HY-1 A has been constructed. It receives 1B data from the satellite, outputs sea ice images and provides digital products of ice concentration, ice thickness and ice edge, which can be used as important information for sea ice monitoring and the initial fields of the numeric sea ice forecast and as one of the reference data for the sea ice forecasting verification. The sea ice retrieval system of the satellite is described, including its processes, methods and parameters. The retrieving results and their application to the sea ice monitoring and forecasting for the Bohai Sea are also discussed.

关键词： oceanic satellite sea ice retrieval sea ice monitoring and forecasting CCD COCTS

Analysis on Performance relation between time-frequency architecture and positioning service of a satellite navigation system

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Analysis on Performance relation between time-frequency arch...

第三届中国卫星导航学术年会

作者： Jun LU 1 ,Zhi-Wu CAI 2,3.*,Hong-Wei ZHOU 1 1 beijing Tracking and Communication Technology Institute,beijing,100094.2 beijing Global Information {3. and Development {4.,beijing,100094.3.Nanjing University of Aeronautics and Astronautics,Nanjing,210000

Performance improvement of time and frequency technology has played a key role in GPS URE accuracy *** time and frequency elements related to system service performance were analyzed and concluded based on positioning theory and main error sources analysis regarding actual engineering situation,such as system time, clock,time comparison and so *** to URE performance requirement,the performance analysis architecture about time and frequency indexes were put forward for the first *** relation model between time and frequency indexes and URE clock component and its error estimation formula were studied and *** were made and reference data about time and frequency indexes and URE were *** result may be used as technique reference to satellite navigation system research and Chinese Beidou system development.

关键词： satellite Navigation URE Clock deviation predication Time and Frequency Performance decomposition

Secular changes in differential code bias of COMPASS system

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Secular changes in differential code bias of COMPASS system

第三届中国卫星导航学术年会

作者： XING Nan1,2**WU Xiaoli3.U Xiaogong1SU Ranran3. Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 20003., China 2 Graduate University of Chinese Academy of Sciences, beijing 10004., China 3.beijing Global Information {3. of {3. and Exploitation, beijing 100094. China

DCB （Differential Code Bias）, named TGD （Timing Group Delay） for satellite and IFB （Inter-Frequency Bias） for receiver, is a crucial parameter in COMPASS system, which is needed in satellite clock correction and ionospheric delay modeling. Though DCB parameters were measured in laboratory initially, it may change with working environment as well as with time elapsed, necessitating DCB estimation for the deployed satellites and receivers. DCB estimates can be obtained by combining COMPASS {3. in 3.frequencies and accurate ionospheric TEC （Total Electron Content） models （e.g. Global Ionosphere Model, GIM from International GNSS Service）. However, TEC model errors as revealed by discrepancies with GPS observations would translate into and contaminate DCB estimates. This study concludes that the error GIM brought into TGD is under 1ns that is equivalent to a positioning error of 0.18m, an ionospheric time delay correction error of 0.4.0.7m and TEC models error of 3.ECU. Analysis of COMPASS {3. for 290 days in 2011 shows a secular change in TGDs with amplitude of about 1.5ns for GEO satellites and 4.s for IGSO satellites respectively and in IFBs with amplitude of 3.s. The DCB time series could be well fitted by a second-degree polynomial with residuals of 0.4.0.6ns for TGDs and 0.6-0.9ns for IFBs, based on which the TGD could be predicted with accuracy of 0.5ns for GEO satellites and 0.5-1ns for IGSO satellites respectively.

关键词： COMPASS DCB TGD

A double difference measuring method of pseudo-range precision using to the real environment

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A double difference measuring method of pseudo-range precisi...

第三届中国卫星导航学术年会

作者： Chunxia Li, Jinping Chen, Henglin Chu beijing Global Information application and Development center, beijing 100094. China

The pseudo-range measurement precision is an important index for evaluating the performance of a navigation receiver, and also one of the important factors for analyzing the receiver’s positioning precision. In the real environment the pseudo-range is varying and it is difficult to measure its precision, so usually the pseudo-range precision is measured on a laboratory simulation condition. But this measuring method could not truly reflect the pseudo-range precision in the real environment. In this paper, a measuring method of pseudo-range precision using to the real environment, namely receiver and satellite double difference method, is presented. Its theory basis is given by deducing its mathematic model, and then experiment is made on pseudo-range precision measuring with this method. The results of the experiment show that when the receiver is stationary, this method can accurately measure the precision of its observation pseudo-range to a static satellite, and can accurately measure the precision of its observation pseu-do-range to a motional satellite by controlling the observation time. Finally the obtained pseudo-range precisions are used to compare the precisions of two posi-tioning modes, and the comparison relationship of the precisions of the two posi-tioning modes observed in the real {3. is intuitively revealed.

关键词： double difference pseudo-range measure precision real environment positioning precision