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Real-time Maximum Correlation Matching Based on Approximated Local Gravity Map

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Real-time Maximum Correlation Matching Based on Approximated...

第三届中国卫星导航学术年会

作者： TONG Yu-de 1 BIAN Shao-feng 1,2.JI Bing 1 1 Department of Navigation, Naval University of Engineering, Wuhan 43.03., china 2.Institute of {3. and {2., chinese Academy of Sciences, Wuhan 43.077, china

Firstly, the limitations of the traditional maximum correlation matching algorithm is analyzed and the new algorithm to approximate local grid gravity anomaly map with the tensor product of Gauss spline function is proposed to get the continuous analytic expression of local gravity anomaly map. Then, the mathematical model of maximum correlation matching algorithm is redesigned based on this unified analytic expression and the BFGS Quasi-Newton method is adopted to solve this non-linear model. With respect to the bad real-time performance of traditional maximum correlation matching algorithm, the way fixing the length of sample sequence is adopted to improve sampling structure and the conversion formula between two rigid transformations centered with different points is derived. Finally, the real-time maximum correlation matching algorithm based on continuous analytic expression of local gravity anomaly map is realized. Two simulations have been done based on 2.×2. gravity anomaly database from satellite altimetry inversion for the comparative analysis. From the simulation results, we can see that the matching results of new algorithm can track the actual path with high precision in case of relatively big observation noise and initial position errors.

关键词： Inertial navigation system Gravity map approximation Real-time Maximum correlation Aided navigation

Ce Anomalies of the Yangtze Region,South china,through the Ordovician and Silurian Transition

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Journal of Earth Science 2009年第6期20卷 941-948页

作者：严德天张丽琴李双建 Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of GeosciencesWuhan Institute of Geology and geophysics Chinese Academy of Sciences School of geodesy and Geomatics Wuhan University Key Laboratory of Geospace Environment & geodesy of Ministry of Education Wuhan University Petroleum Exploration and Production Institute of SINOPEC

Systematic Ce anomalies for whole-rock have been obtained from the shale-dominated, continuous, and pelagic sedimentary sequences spanning the Ordovician/Silurian （O/S） boundary at the Tieshui （铁水） of Xiushan （秀山）, Chongqing （重庆）, South china. Ce anomalies across the O/S boundary are recognized in three intervals, Wufeng （五峰）, Guanyinqiao （观音桥） and Longmaxi （龙马溪）. The calculated Ce/Ce＊ values of Wufeng Formation range from 0.84 to 0.96 （avg. 0.90）. In the Guanyinqiao Formation, the values of calculated Ce/Ce＊ range from 0.73.to 0.85 （avg. 0.79）. The Ce/Ce＊ values of uppermost Longmaxi Formation range from 0.87 to 0.96 （avg. 0.91）. All along the section, the magnitude of the Ce anomaly is always negative, but is more significant in the Guanyinqiao Formation. The relatively higher Ce/Ce＊ values in the Wufeng and Longmaxi shales are likely to be due to the sediments deposited under rather reducing conditions. The Ce anomaly apparently does play some regular roles in the anoxic events that accompany prominent mass extinctions, and this work provides new data of critical importance for constraining models on the end-Ordovician anoxic events and mass extinctions.

关键词： Ce anomaly redox mass extinction Ordovician/Silurian boundary Yangtze platform.

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The free-core-nutation of triaxial Earth

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The free-core-nutation of triaxial Earth

第五届国际非线性力学会议

作者： Wen-jun Wang~1,Han-wei Zhang~1,Wen-bin Shen~2.(1.School of Surveying,Henan Polytechnic University,Jiaozuo,china 2.Department of {3./Key Lab.of Geospace Environment and {2.,School of {2. and Geomatics,Wuhan University,china)

＜正＞Earth’s principal moments of inertia possess no biaxiality with the difference of A to B only 1/150 of that of A to *** that of the fluid core is 1/*** the former Earth rotation theory treats the rotation according to biaxial Earth ignoring the difference of A to *** of the works considered the effects of the difference on the flee normal modes of Chandler wobble and ffee-core-nutation（FCN）.Those works discovered that the approximations had high enough ***,the former Earth rotation theory can hardly explain many mechanisms of terms of long period polar *** this study,following the theorem that the solution of rotation for triaxial body may be decompounded as straight product of three single pendulums with two positively hung and one inversely set,and the result that the rotation may have two stable elliptic trajectories and one instable saddle point for the case of single plane inverted pendulum,we obtain from Poincar（?）’s core-mantle coupling model twin flee polar motions and twin FCNs.

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Ionospheric eclipse factor method (IEFM) for determining the ionospheric delay using GPS data

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Progress in Natural Science:Materials International 2004年第9期 56-60页

作者： YUAN Yunbin* and OU Jikun(Key Laboratory of Dynamic geodesy, Institute of geodesy and {2., {3. Academy of Sciences, Wuhan 43.077, china) Key Laboratory of Dynamic geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China

By establishing the ionospheric eclipse factor (IEF) λ of the ionospheric pierce point (IPP) and its ionospheric influence factor (IFF) , and combining λ, with t of IPP, a new method of modeling high precision ionospheric delay using GPS data—ionospheric eclipse factor method (IEFM)—is presented in this paper. The IEFM can effectively select the proper ionospheric models to model the total electron content (TEC) with different changes corresponding to annual, seasonal and diurnal variations. Initial experimental results show that the correction precision of ionospheric delay modeled by the IEFM seems to be close to that of using L3.GPS observations to directly correct the corresponding ionospheric delay.

关键词： global positioning system (GPS) ionospheric delay total electron content ionospheric eclipse factor method.

A generalized trigonometric series function model for determining ionospheric delay

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Progress in Natural Science:Materials International 2004年第11期 74-78页

作者： YUAN Yunbin* and OU Jikun(Key Laboratory of Dynamical geodesy, Institute of geodesy and {2., {3. Academy of Sciences, Wuhan 43.077, china) KeyLaboratoryofDynamicalgeodesy InstituteofGeodesyandGeophysicsChineseAcademyofSciencesWuhan430077China

A generalized trigonometric series function (GTSF) model, with an adjustable number of parameters, is proposed and analyzed to study ionosphere by using GPS, especially to provide ionospheric delay correction for single frequency GPS users. The preliminary results show that, in comparison with the trigonometric series function (TSF) model and the polynomial (POLY) model, the GTSF model can more precisely describe the ionospheric variation and more efficiently provide the ionospheric correction when GPS data are used to investigate or extract the earth’s ionospheric total electron content. It is also shown that the GTSF model can further improve the precision and accuracy of modeling local ionospheric delays.

关键词： global positioning system (GPS) ionospheric delay total electron content (TEC).

Rational formulation of modern geoid concept

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中国有色金属学会会刊：英文版 2011年第S3期21卷 675-680页

作者： GUO Zeng-zhang, XIAO Jian-hua geodesy Institute, Henan Polytechnic University, Jiaozuo 454000, china geodesy Institute Henan Polytechnic University Jiaozuo 454000 China

Based on modern geometrical field theory, a rational interpretation of modern geodesic surface concept was formulated. The general equations for geodesic surface were given. The height concept and arc length concept were formulated strictly. Their intrinsic benefits and shortages of parameter-center reference and mass-center reference systems were studied in details. The research results show that the geodesic concept depends on the available technology. The technology-dependence feature of geodesy concept was expressed by related mathematic formulations. For the satellite-based observation system, the rationality of china-2.00 Geoid Reference System was explained. Discussions about how to establish regional precision reference system were made based on general equations of arc length and space distance equations. A new correction item should be taken into consideration for arc length gauge calculation.

关键词： geodesic surface parameter-center system mass-center system geodesy deformation geoid

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Intensive radiosonde observations of gravity waves in the lower atmosphere over Yichang （111°18′E,3.°42.N）,china

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Intensive radiosonde observations of gravity waves in the lo...

第十二届全国日地空间物理学术讨论会

作者： Shao Dong ZHANG~(1,2.3. Fan YI~(1,2.3. Chun Ming HUANG~(1,2.3. 1 School of Electronic Information,Wuban University,Wuhan,Hubei,People''s Republic of {3. 2.Key Laboratory of Geospace Environment and geodesy,Ministry of Education,Wuhan,Hubei,People''s Republic of {3. 3.State Observatory for Atmospheric Remote Sensing.Wuhan,People''s Republic of {3.

＜正＞The characteristics of dynamical and thermal structures and inertial gravity waves （GWs） in the troposphere and lower stratosphere （TLS） over Yichang （111°18′E,3.°42.N） were statistically studied by using the data from intensive Radiosonde observations in August 2.06 （summer month） and January 2.07

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水分布激发与周年极移

天文学报 1992年第1期33卷 61-66页

作者：雷小平高布锡中国科学院测量与地球物理研究所武汉430077

本文作者利用全球近3.0个气象台站的月降水量及月均温度资料,联合国教科文组织(UNESCO)给出的全球陆地径流系数,Lamb和Van Hylkama求出的陆地蒸发量数据,求得从1979年到1989年逐月的水分布激发函数,并与周年极移作了对比研究。计算结果... 详细信息

本文作者利用全球近3.0个气象台站的月降水量及月均温度资料,联合国教科文组织(UNESCO)给出的全球陆地径流系数,Lamb和Van Hylkama求出的陆地蒸发量数据,求得从1979年到1989年逐月的水分布激发函数,并与周年极移作了对比研究。计算结果表明:水分布变化对周年极移有较大贡献,可以很好地用大气及水分布变化引起的激发解释周年极移运动。

关键词：水分布变化周年地极移动

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Pn Tomographic Velocity and Anisotropy beneath Western china and the Surrounding Region

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Pn Tomographic Velocity and Anisotropy beneath Western China...

中国地球物理学会第二十七届年会

作者： L(u|¨)Yan~(1,3.) Ni Sidao~(2.1) Liu Bin~1 Sun Youshun~3.1.School of Earth and Space Sciences,University of Science and Technology of china,Hefei,2.002.,china 2.Key Laboratory of Dynamical {2.,Institute of {2. and geophysics,Wuhan,43.077,china 3.Department of Earth,Atmospheric and Planetary Sciences,Massachusetts Institute of Technology, Cambridge,Massachusetts 02.3.,USA

＜正＞Western china and the adjacent region include china’s Tarim Basin,the Tibetan Plateau,the Sichuan-Yunnan region,and Afghanistan,India,Myanmar,and other neighboring *** tectonics of the area is currently controlled by the collision and continuing convergence of the Indian Plate and the Eurasian *** northward movement of the Indian Plate has been widely accepted as the driving force for growth of the Tibetan plateau;however,the mechanism of subduction is still unclear and requires further *** the uppermost mantle, changes in composition,temperature,pressure and water volatile content contribute to Pn velocity ***

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