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Uppermost mantle structure of the North china Craton:Constraints from interstation Pn travel time difference tomography

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Uppermost mantle structure of the North China Craton:Constra...

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： LI ZhiWei~(1,2),HAO TianYao~(1*) & XU Ya~1 ~1Key Laboratory of Petroleum Resources Research,institute of Geology and geophysics,chinese academy of sciences,Beijing 100029,china ~2Key Laboratory of Dynamical geodesy,institute of geodesy and geophysics,chinese academy of sciences,wuhan 430077,china

The uppermost mantle is the key area for exchange of heat flux and material convection between the crust and lithospheric mantle. Spatial variations of lithospheric thinning and dynamic processes in the North china Craton could inevitably induce the velocity heterogeneity in the uppermost *** this study,we used Pn arrivals from permanent seismic stations in North china and surrounding regions to construct a tomographic image of the North china *** tomographic method with Pn travel time difference data were used to study the velocity variations in the uppermost *** velocities in the uppermost mantle varied significantly in the Eastern,Central and Western blocks of the North china *** suggests that the lithosphere beneath different blocks of the North china Craton have experienced distinct tectonic evolutions and dynamic processes since the Paleozoic. The current uppermost mantle has been imprinted by these tectonic and dynamic *** Pn velocities are prominent beneath the Bohai Bay Basin in the Eastern Block of the North china Craton,suggesting residuals of the Archean lithospheric *** the Tanlu Fault Zone and Bohai Sea,slow Pn velocities are present in the uppermost mantle,which can be attributed to significant lithospheric thinning and asthenospheric *** newly formed lithospheric mantle beneath Yanshan Mountain may be the dominant reason for the existence of slow Pn velocities in this ***,the ancient lower crust and lithospheric mantle already have been *** the Central Block,significant slow Pn velocities are present in Taihangshan Mountain,which also extends northward to the Yinchuan-Hetao Rift on the northern margin of the Ordos Block and Yinshan *** characteristic probably is a result of hot asthenospheric upwelling along the active tectonic boundary on the margin of the Western *** protracted thermal erosion and underplating of hot asthenospheric upwelling may induce

关键词： North china Craton Lithospheric thinning Uppermost mantle Pn travel time difference Cratonic destruction

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对GPS模糊度解相关方法的一种改进

同济大学学报（自然科学版） 2004年第2期32卷 237-241页

作者：楼立志中国科学院测量与地球物理研究所湖北武汉430077 同济大学测量与国土信息工程系上海200092

在双差载波相位模型中,整数-实数混合平差是无法避免的.通常的参数估计方法如加权最小二乘,只能给出浮点解,包括模糊度向量也只是实数解.为了加速整周模糊度的搜索过程,解相关的方法得到了应用,并被证明是行之有效的.在此,主要讨论了LL... 详细信息

在双差载波相位模型中,整数-实数混合平差是无法避免的.通常的参数估计方法如加权最小二乘,只能给出浮点解,包括模糊度向量也只是实数解.为了加速整周模糊度的搜索过程,解相关的方法得到了应用,并被证明是行之有效的.在此,主要讨论了LLL方法.为了对该解相关方法的分析尽可能地具有现实和统计意义,利用随机模拟方法得到了没有任何先验信息的对称正定矩陈,作为模糊度向量的方差-协方差矩阵.针对现有方法中的不足,提出了改进后的LLL方法,并利用条件数作为评判解相关程度的准则,证明其是切实可行的.

关键词：全球定位系统解相关随机模拟条件数

潜育化作用对水稻土磷素形态与供磷能力的影响

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土壤通报 2002年第4期33卷 275-277页

作者：陈世俭马毅杰中国科学院测量与地球物理研究所湖北武汉4430077 中国科学院南京土壤研究所江苏南京210008

本文对江汉平原四湖地区几个不同潜育度水稻土剖面的磷素状况及其有效性进行了研究 ,并用张守敬—Jakson无机磷分级法做无机磷分级。结果表明 ,土壤潜育化程度对土壤全磷没有明显的影响 ,对土壤磷素形态及其有效性有明显的影响。随着土... 详细信息

本文对江汉平原四湖地区几个不同潜育度水稻土剖面的磷素状况及其有效性进行了研究 ,并用张守敬—Jakson无机磷分级法做无机磷分级。结果表明 ,土壤潜育化程度对土壤全磷没有明显的影响 ,对土壤磷素形态及其有效性有明显的影响。随着土壤潜育化程度加重 ,无机磷中的O—P含量有增加趋势 ,其占土壤无机磷的百分数增大 ;土壤有机磷也随之增加 ;但有效磷含量减少。

关键词：潜育化作用水稻土磷素形态供磷能力无机磷分级

Partial continuation model and its application in mitigating systematic errors of double-differenced GPS measurements

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Progress in Natural Science:Materials International 2005年第3期 54-59页

作者： GUO Jianfeng 1,2 ˇˇ ,OU Jikun 1 and REN Chao 1 (1.Key Laboratory of Geodynamics,institute of geodesy and geophysics,chinese academy of sciences,wuhan430077,china 2.Graduate School of the chinese academy of sciences,Beijing100039,china) Key Laboratory of Geodynamics，institute of geodesy and geophysics，chinese academy of sciences，wuhan 430077，china Graduate School of the chinese academy of sciences，Beijing 100039，china Key Laboratory of Geodynamics，institute of geodesy and geophysics，chinese academy of sciences，wuhan 430077，china

Based on the so-called partial continuation model with exact finite measurements,a new stochastic assessment procedure is *** every satellite pair,the temporal correlation coefficient is estimated using the original double-differenced(DD)GPS *** then,the Durbin-Watson test is applied to test specific hypothesis on the temporal correlation *** the test is not significant with a certain significant level,a data transformation is *** transformed measurements are free of time *** purpose of illustration,two static GPS baseline data sets are analyzed in *** experimental results demonstrate that the proposed procedure can mitigate effectively the impact of systematic errors on DD GPS measurements.

关键词： partial continuation model systematic errors GPS double-differenced measurements.

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卫星双向时间比对及其误差分析

天文学进展 2004年第3期22卷 219-226页

作者：刘利韩春好信息工程大学测绘学院郑州450052 中国科学院测量与地球物理研究所武汉430077

介绍了卫星双向时间比对(TWSTT)方法的发展过程及其基本原理,讨论了TWSTT的误差源,分析了各误差源对比对精度的影响.得出影响TWSTT精度的主要误差源为设备时延误差和路径传播时延误差,而由于卫星和地面站运动引起的误差相对较小,从而给... 详细信息

介绍了卫星双向时间比对(TWSTT)方法的发展过程及其基本原理,讨论了TWSTT的误差源,分析了各误差源对比对精度的影响.得出影响TWSTT精度的主要误差源为设备时延误差和路径传播时延误差,而由于卫星和地面站运动引起的误差相对较小,从而给出了实际应用时不同比对精度下需要考虑的误差源及对误差源的精度要求.

关键词：天体测量学卫星双向时间比对(TwSTT) 综述时间误差

Application of adaptive filtering by selecting the parameter weight factor in precise kinematic GPS positioning

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Progress in Natural Science:Materials International 2005年第1期 42-47页

作者： REN Chao 1,2*, OU Jikun 1 and YUAN Yunbin 1 (1. institute of geodesy and geophysics, chinese academy of sciences, wuhan 430077, china 2. Guilin institute of Technology, Guilin 541004, china) institute of geodesy and geophysics，chinese academy of sciences，wuhan 430077，china Guilin institute of Technology Guilin 541004，China institute of geodesy and geophysics，chinese academy of sciences，wuhan 430077，china

A new method of adaptive filtering by selecting the parameter weight factor is introduced in this paper. Based on the theoretical analysis and research, this method is firstly used for precise kinematic GPS positioning with single frequency double-differenced (DD) carrier phase observations. Two numerical examples are given to illustrate the feasibility and validity of the method. The preliminary results show that precise positioning results can be obtained by using only the GPS single frequency DD carrier phase measurements for short baselines with the new method.

关键词： adaptive filtering parameter weight factor precise kinematic GPS positioning.

The diurnal variations, semiannual and winter anomalies of the ionospheric TEC based on GPS data in china

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Progress in Natural Science:Materials International 2005年第1期 57-61页

作者： HUO Xingliang 1,2*, YUAN Yunbin 1, OU Jikun 1, WEN Debao 1,2 and LUO Xiaowen 1,2(1. Key Laboratory of Dynamic geodesy, institute of geodesy and geophysics, chinese academy of sciences, wuhan 430077, china 2. Graduate School of chinese academy of sciences, Beijing 100039, china) Key Laboratory of Dynamic geodesy，institute of geodesy and geophysics，chinese academy of sciences，wuhan 430077，china Graduate School of chinese academy of sciences，Beijing 100039，china Key Laboratory of Dynamic geodesy，institute of geodesy and geophysics，chinese academy of sciences，wuhan 430077，china

With the spherical harmonic (SH) function model and the dual frequency GPS P code phase data from the Crustal Movement Observation Network of china (CMONOC) during the period from year 2000 to 2002, time series of total electron content (TEC) in the area of china is calculated. The diurnal variations, semiannual, and winter anomalies of the ionosphere in the area of china are analyzed and discussed, especially according to the results of year 2001.

关键词： Global Positioning System spherical harmonic function model total electron content semiannual anomaly winter anomaly.

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 430033, china 2 institute of geodesy and geophysics, chinese academy of sciences, wuhan 430077, 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

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利用地形图批量生产DEM数据的方法

上海师范大学学报（自然科学版） 2003年第2期32卷 83-86页

作者：王茜薛怀平吴胜军徐新刚中国科学院测量与地球物理研究所武汉430077

数字高程模型(DEM)在生产中的应用越来越广泛,作者结合实际工作,探讨了一种以地形图为基础资料,通过扫描、屏幕数字化生产DEM数据的方法和过程。结果显示,用这种方式生产出来的DEM数据成本低廉、生产周期短,可批量生产,有较高的实用价值。

关键词：地形图矢量化批量生产 DEM