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Separation of systematic errors in processing high precision GPS baselines

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中国有色金属学会会刊：英文版 2005年第S1期15卷 139-141页

作者： WANG Zhen-jie~(1, 2., QU Guo-qing~2.(1. institute of Architectural Engineering, Shangdong University of Technology, Zibo 2.5012. china {2., chinese academy of sciences, wuhan 430077,china) Shandong Univ Technol Inst Architectural Engn Zibo 255012 Peoples R China chinese Acad Sci Inst Geodesy & Geophys Wuhan 430077 Peoples R China

The research is based on the double difference observations and semi-parametric model. Systematic errors are considered as the parameters to be estimated, and brought into the GPS observation equations. High precision baselines are obtained after separating systematic errors. The crucial steps are choosing regularizer and regularization parameters in processing GPS systematic errors by using the semi-parametric model. We propose a new regularizer and apply it to dealing with systematic errors. Also, we compare it with one proposed by other researchers. This comparison is done when all the regularization parameters equal to one. The computation result of the example shows that two regularizers correspond well and they can separate systematic errors successfully. Thus, we can get high precision baselines. Compared with R=QK-1Q′, our regularizer R=GTG is simple, so, the process of resolving the high precision baselines is relatively simple.

关键词： GPS systematic errors semi-parametric model regularizer

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基于积分方程正则化的重力异常超定问题解法

同济大学学报（自然科学版） 2002年第11期30卷 1337-1341页

作者：沈云中许厚泽同济大学测量与国土信息工程系上海200092 中国科学院测量与地球物理研究所湖北武汉430077

地球重力场的观测信息越来越丰富,求解重力异常的超定模型将具有实用价值。据此给出了基于第一类Fredholm型积分方程离散型解法求解重力异常的超定模型,建立了地面重力、测高数据、重力梯度和垂线偏差求解重力异常的观测方程,并给出求... 详细信息

地球重力场的观测信息越来越丰富,求解重力异常的超定模型将具有实用价值。据此给出了基于第一类Fredholm型积分方程离散型解法求解重力异常的超定模型,建立了地面重力、测高数据、重力梯度和垂线偏差求解重力异常的观测方程,并给出求解病态观测方程的正则化算法。

关键词：积分方程重力异常地球重力场超定问题正则化算法离散型解法

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弹性地球极移和章动的联合动力学方程

山东科技大学学报（自然科学版） 2004年第4期23卷 1-4,11页

作者：张捍卫许厚泽王爱生徐州师范大学国土信息与工程系江苏徐州221116 中国科学院测量与地球物理研究所湖北武汉430077

基于经典的弹性地球自转动力学理论,通过引入章动坐标系相对惯性空间的运动,推导出一个同时包含极移和章动的弹性地球自转联合动力学方程。在推导过程中首次考虑了高阶岁差章动力矩和其它摄动因素(摄动周期满足0.5d≤T≤1.5d)对地球自... 详细信息

基于经典的弹性地球自转动力学理论,通过引入章动坐标系相对惯性空间的运动,推导出一个同时包含极移和章动的弹性地球自转联合动力学方程。在推导过程中首次考虑了高阶岁差章动力矩和其它摄动因素(摄动周期满足0.5d≤T≤1.5d)对地球自转的影响,从而使得方程更加完备和完美,与现行的地球自转动力学方程相比较表明,该方法综合性强而且易于理解。

关键词：章动坐标系极移和章动联合动力学方程

Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2. 3, ZHANG Jin4 1. institute of geodesy and {2., chinese academy of sciences, wuhan 430077, china 2. Key Laboratory of Dynamic geodesy, institute of geodesy and {2., chinese academy of sciences, wuhan 430077, china 3. Graduate School of chinese academy of sciences, Beijing 100049, china 4. Department of Surveying and Mapping, Taiyuan University of Technology, Taiyuan 03002., china Taiyuan Univ Technol Dept Surveying & Mapping Taiyuan 030024 Peoples R China chinese Acad Sci Inst Geodesy & Geophys Key Lab Dynam Geodesy Wuhan 430077 Peoples R China chinese Acad Sci Grad Sch Beijing 100049 Peoples R China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine

Atmospheric gravity Green's functions

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chinese Science Bulletin 1997年第20期42卷 1712-1719页

作者： SUN HepingLaboratory of Dynamic geodesy, institute of geodesy and geophysics, chinese academy of sciences, wuhan 430077, china Laboratory of Dynamic geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China

THE observational accuracy of the superconducting gravimeter has now reached 0.1 μGal levelor better, with characteristics of the low noise, high sensitivity and better continuity and sta-bility. It will play an important part in the study of the change in (non-) tidal gravity signals,especially in the application of the geophysics and geodynamics. However, the instrument

关键词： air pressure Green’s functions atmospheric gravity admittance.

Determination of vertical gradient of gravity anomaly with topographic data

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chinese Science Bulletin 1999年第11期44卷 1029-1034页

作者： ZHANG Chijuninstitute of geodesy and {2. , chinese academy of sciences , wuhan 430077 , china institute of geodesy and {2. Chinese Academy of Sciences Wuhan China

The role of vertical gradient of gravity anomaly in the solution and interpretation of geological and geophysical problems on superficial layer is increasingly evident. However, it is difficult to directly observe the vertical gradient of gravity anomaly in mountainous area. Moreover,aerial and satellite gravity gradient measurments have not been put into practice up to date *** vertical gradient of gravity anomaly is calculated by use of topographic data and several problems concerned are investigated and discussed. It turns out in theory and practice that the relative error of the vertical gradient determined with the method is only 5%, and when the vertical gradient of gravity anomaly reaches the maximum 1 000 ns-2./sup> the error is only 50 ns-2./sup>. In addition, how to divide ring zones in calculation and the errors caused by the inaccuracy of landform elevation and rock density has been quantitatively analysed.

关键词： vertical gradient gravity anomaly topographic mass geoid.

Determination of geoid and elevation of the Mt. Qomolangma and discussion on the role of vertical gravity gradient

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chinese Science Bulletin 1997年第20期42卷 1723-1725页

作者： ZHANG Chijuninstitute of geodesy and {2., chinese academy of sciences, wuhan 430077, china institute of geodesy and {2. Chinese Academy of Sciences Wuhan 430077 China

IT is known that the Mt. Qomolangma is the highest peak in the world. It was recorded in the'Map of Complete Territory of the Qin Dynasty' (published in 1717). As the highest peak,the Mt. Qomolangma not only provokes the interest of climbers but also arouses much atten-tion of geodesists. A significant cause is that the Mt. Qomolangma is located in the collisionbelt between the Indian Plate and the Eurasian Plate. According to the relative

关键词： geoid orthometric height the Mt. Qomolangma.

Improved retracking algorithm for oceanic altimeter waveforms

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Progress in Natural Science:Materials International 2009年第2期19卷 195-203页

作者： Lifeng Bao,Yang Lu,Yong Wang institute of geodesy and {2.,chinese academy of sciences,wuhan 430077,china [a]institute of geodesy and {2. Chinese Academy of Sciences Wuhan 430077 China

Over the deep oceans without land/ice interference,the waveforms created by the return altimeter pulse generally follow the ocean model of Brown,and the corresponding range can be properly determined using the result from an onboard tracker. In the case of com-plex altimeter waveforms corrupted due to a variety of reasons,the processor on the satellite cannot properly determine the center of the leading edge,and range observations can be in error. As an efficacious method to improve the precision of those altimeter observations with complex waveforms,waveform retracking is required to reprocess the original returning pulse. Based on basic altimeter theory and the geometric feature of altimeter waveforms,we developed a new altimeter waveform retracker,which is valid for all altimeter wave-forms once there exists a reasonable returning signal. The performances of the existing Beta-5 retracker,threshold retracker,improved threshold retracker,and the new retracker are assessed in the experimental regions (china Seas and its adjacent regions),and the improvements in the accuracy of sea surface height are investigated by the difference between retracked altimeter observations and ref-erenced geoid. The comparisons denote that the new algorithm gives the best performance in both the open ocean and coastal regions. Also,the new retracker presents a uniform performance in the whole test region. Besides,there is a significant improvement in the short-wavelength precision and the spatial resolution of sea surface height after retracking process.

关键词： Altimetry Waveform retracking Sea surface height

The GPS-gravimetry boundary value problem

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Science china Earth sciences 2005年第3期48卷 398-405页

作者： YU Jinhai1,2.& ZHANG Chuanding2.1. institute of geodesy and {2. of chinese academy of sciences, wuhan 430077, china 2. Zhengzhou Information Engineering University, Zhengzhou 450052. china 1. institute of geodesy and {2. of chinese academy of sciences 430077 Wuhan China 2. Zhengzhou Information Engineering University 450052 Zhengzhou China

How to determine the earth’s external gravity field with the accuracy of O(T2. by making use of GPS data and gravity values measured on the earth’s surface is dealt with in this paper. There are two main steps: to extend these measured values on the earth’s surface onto the reference ellipsoid at first and then to seek for the integral solution of the external Neumann problem outside the ellipsoid. In addition, the corresponding judging criteria of accuracy to solve the GPS-gravity boundary value problem are established. The integral solution given in the paper not only contains all frequency-spectral information of the gravity field with the accuracy of O(T 2., but is also easily computed. In fact, the solution has great significance for both theory and prac- tice.

关键词： Neumann boundary value problem, integral solution, gravity disturbance.