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chinese Geographical Science 2003年第3期13卷 272-276页

作者： WANG Xue-lei, NING Long-mei, HU Wang-bin(institute of {1. and Geophysics,{2., wuhan 430077, P. R. China) institute of {1. and Geophysics Chinese Academy of Sciences Wuhan P. R. China

Wetlands in the Jianghan Plain are important components of wetland types in lake area in the middle and lower reaches the Changjiang (Yangtze) River and they fulfill many uses and functions related to hydrology, waste assimilation, ecosystem productivity and biodiversity. Owing to natural factors and human activities, especially excessive reclamation from lakes, the shrinking process of the lakes has been accelerated. Wetland ecosystem has shown the characteristics of vulnerability. According to the analysis of wetland ecological function in the Jianghan Plain, this paper presented an index system related to productivity, stability and environmental capacity. By using the method of Analytic Hierarchy Process, we computed the values of the relative weights of the indexes, and evaluated the vulnerability level of the wetland ecosystem by the method of multi-indexes. The case study showed that the fragile extent of wetland ecosystem in the Jianghan Plain is 5.6. This means that the wetland ecosystem in the Jianghan Plain is laid to the state of middle vulnerability. Therefore, the wetland conservation and eco-rehabilitation in the Jianghan Plain should be paid attention to.

关键词： wetland ecological vulnerability AHP the jianghan plain

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 1.0039, China) Key Laboratory of Dynamic geodesy，{1. of geodesy and Geophysics，chinese academy of sciences，wuhan 430077，China Graduate School of chinese academy of sciences，Beijing 1.0039，China Key Laboratory of Dynamic geodesy，{1. 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 2.00 to 2.02. 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 2.01.

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

Determination of ocean tide loading displacements in Hong Kong using GPS technique

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Science China Earth sciences 2010年第7期53卷 993-1007页

作者： YUAN LinGuo1.3, DING XiaoLi1. SUN HePing2. ZHONG Ping1.3 & CHEN Wu1.1.Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China 2.Key Laboratory of Dynamic geodesy, institute of geodesy and Geophysics, chinese academy of sciences, wuhan 430077, China 3 Department of Surveying Engineering, School of Civil Engineering, Southwest Jiaotong University, Chengdu 61.031. China 1. Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic University Kowloon Hong Kong China3. Department of Surveying Engineering School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China2. Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China

Ocean tide loading (OTL) displacements of eight principal constituents at 1.0}sites in Hong Kong were determined using more than eight years of continuous GPS observations. Parameters of the OTL displacements were estimated using daily GPS solutions obtained with precise point positioning (PPP) technique. The results were compared with predictions from seven latest global ocean tide models. Gravity measurements of OTL in Hong Kong were also used to validate the GPS results. The study shows that the results from both the GPS and gravity measurements agree best with the GOT4.7 and NAO99b models, when the K1.and K2.constituents are excluded. The agreements between the GPS and the model estimates are generally at sub-millimeter level in both the horizontal and vertical directions, except for S2. K2.and K1.constituents that have relatively larger errors. After removing the systematic biases between the GPS and the model estimates, the misfits of M2. S2. N2. O1. P1.and Q1.at all sites are within 0.5 and 1.0 mm in the horizontal and the vertical directions, respectively, whereas K1.and K2.show relatively larger misfits of up to 2.3 mm. Both the GPS and the gravity S2.estimates have large biases with unknown reasons when compared with the modeled values, which needs to be further investigated. The study demonstrates that GPS is capable of estimating the OTL displacements with the same accuracy as the model predictions, especially for coastal areas.

关键词： GPS ocean tide loading ocean tide model site displacement

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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

Experimental earth tidal models in considering nearly diurnal free wobble of the Earth's liquid core

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Science Bulletin 2003年第9期48卷 935-940页

作者： SUN Heping, XU Jianqiao & B. Ducarme Key Laboratory of Dynamic geodesy, {1. of geodesy and Geophysics, chinese academy of sciences, wuhan 430077, China Observatoire Royal de Belgique, Av. Circulaire 3, B-1.80, Brussels, Belgium Correspondence should be addressed to Sun Heping (e-mail: heping@ ***) 1. Key Laboratory of Dynamic geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China 2. Observatoire Royal de Belgique}{srAv. Circulaire 3 B-1180 Brussels Belgium

Based on the 2. series of the high precision and high minute sampling tidal gravity observations at 2. stations in Global Geodynamics Project (GGP) network, the resonant parameters of the Earth's nearly diurnal free wobble (including the eigenperiods, resonant strengths and quality factots) are precisely determined. The discrepancy of the eigenperiod between observed and theoretical values is studied, the important conclusion that the real dynamic ellipticity of the liquid core is about 5% larger than the one under the static equilibrium assumption is approved by using our gravity technique. The experimental Earth's tidal gravity models with considering the nearly diurnal free wobble of the Earth's liquid core are constructed in this study. The numerical results show that the difference among three experimental models is less than 0.1., and the largest discrepancy compared to those widely used nowdays given by Dehant (1.99) and Mathews (2.01. is only about 0.4%. It can provide with the most recent real

关键词： Earth’s nearly diurnal free wobble global observations of superconducting gravimeters dynamic ellipticity of liquid core experimental earth tidal models.

Simulation of the Earth' s gravitational field recovery from GRACE using the energy balance approach

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Progress in Natural Science:Materials International 2005年第7期15卷 596-601页

作者： ZHENG Wei, LU Xiaolei, HSU Houtse, SHAO Chenggang, LUO Jun and WANG Nengchao ( Department of Physics, Huazhong University of Science and Technology, wuhan 430074, China {1. of {2. and Geophysics, chinese academy of sciences, wuhan 430077, China Department of Mathematics, Huazhong University of Science and Technology, wuhan 430074, China) Department of Physics Huazhong University of Science and Technology Wuhan 430074 China. Department of Mathematics Huazhong University of Science and Technology Wuhan 430074 China. institute of {1. and Geophysics Chinese Academy of Sciences Wuhan 430077 China

Based on the measurement principles of GRACE satellites, the observation equations are set up using the energy balance approach. The Earth's gravitational field complete up to degree and order 1.0} is recovered applying the preconditioning conjugate gradient iterative approach by numerical simulation. Assuming an accuracy of 1.μm/s in range-rate measurements of the K-band microwave ranging system, the matching relationships of accuracies of K-band microwave ranging system, SuperSTAR Accelerometer, position vector and velocity vector measurements are investigated.

关键词： the Earth’s gravitational field GRACE satellites energy balance approach preconditioning conjugate gradient method.

Optimal carrier-smoothed-code algorithm for dual-frequency GPS data

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Progress in Natural Science:Materials International 2008年第5期18卷 591-594页

作者： Jianfeng Guo a,b, Jikun Ou a, Yunbin Yuan a, Haitao Wang a a Key Laboratory of Geodynamics, institute of {1. and Geophysics,{2., wuhan 430077, China b institute of Science, Information Engineering University, Zhengzhou 450001. China Key Laboratory of Geodynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China institute of Science Information Engineering University Zhengzhou 450001 China

Carrier-smoothed-code (CSC) algorithm is an e ective pseudorange multipath mitigation technique, which can alleviate the compu- tational burden and reduce the communication bandwidth needed for the transmission of GPS observations. This paper presents an improved Hatch lter and addresses the optimal CSC algorithm for dual-frequency GPS data based on the optimal parameter estimation theory. The smoothed observations have the same information content as that of the raw dual-frequency GPS data from which these are derived. Consequently, the optimal CSC algorithm is equivalent to the uncombined algorithm. Theoretical analyses show that the data precision of the optimal CSC algorithm is better than that of Hatch lter and its improved version.

关键词： GPS Carrier-smoothed-code algorithm Hatch lter Time-invariant combinations

GRACE detection of the medium-to far-field coseismic gravity changes caused by the 2.04 Mw9.3 Sumatra-Andaman earthquake

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Earthquake Science 2012年第3期25卷 235-240页

作者： Jin Li1.2.3 and Wenbin Shen1.3,4, 1.Department of Geophysics, School of {1. and Geomatics, wuhan University, wuhan 430079, China 2.Key Laboratory of Geodynamic {1. of chinese academy, wuhan 430077, China 3 Key Laboratory of Geospace Environment and {1. (Ministry of Education), wuhan University, wuhan 430079, China 4 State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, wuhan 430079, China 1. Department of Geophysics School of Geodesy and Geomatics Wuhan University Wuhan 430079 China 2. Key Laboratory of Geodynamic {1. of chinese {2. Wuhan 430077 China 3. Key Laboratory of Geospace Environment and geodesy (Ministry of Education) Wuhan University Wuhan 430079 China 4. State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan 430079 China

Large earthquakes cause observable changes in the Earth’s gravity field, which have been detected by the Gravity Recovery and Climate Experiment (GRACE). Since most previous studies focus on the detection of near-field gravity effects, this study provides the results from the medium- to far-field gravity changes caused by the 2.04 Sumatra-Andaman earthquake that are recorded within GRACE monthly solutions. Utilizing a spherical-earth dislocation model we documented that large-scale signals predominate in the global field of the coseismic gravity changes caused by the earthquake. After removing the near-field effects, the coseismic gravity changes show a negative anomaly feature with an average magnitude of -0.1.×1.-8 m·s-2.in the region ranging ～40° from the epicenter, which is considered as the 'medium ffield' in this study. From the GRACE data released by Center for Space Research from August 2.02.to December 2.08, we retrieved the large-scale gravity changes smoothed with 3 000 km Gaussian ffilter. The results show that the coseismic gravity changes detected by GRACE in the medium field have an average of (-0.2.±0.06)×1.-8 m·s-2. which agrees with the model prediction. The detection confirms that GRACE is sensitive to large-scale medium-field coseismic gravitational effects of mega earthquakes, and also validates the spherical-earth dislocation model in the medium field from the perspective of satellite gravimetry.

关键词： GRACE medium-to far-field coseismic gravity change 2.04 Sumatra-Andaman earthquake spherical-Earth dislocation model

SCENARIOS SIMULATION OF COUPLING SYSTEM BETWEEN URBANIZATION AND ECO-ENVIRONMENT IN JIANGSU PROVINCE BASED ON SYSTEM DYNAMICS MODEL

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chinese Geographical Science 2005年第3期 29-36页

作者： LIU Yao-bin1. LI Ren-dong2.LI Chun-hua3 (1. School of Management,China University of Mining and Technology,Xuzhou 2.1.08,P. R. China 2. institute of geodesy and Geophysics Research,{2. academy of sciences,wuhan 430077,P. R. China 3. institute of Resource,Beijing Normal University, Beijing 1.0875,P. R. China ) School of Management China University of Mining and TechnologyXuzhou 221008P. R. China institute of {1. and Geophysics Research Chinese Academy of SciencesWuhan 430077P. R. China institute of Resource Beijing Normal UniversityBeijing 100875P. R. China

By means of ISM (Interpretative Structural Modeling) and SD (System Dynamics) methods, this paper made a system dynamics model of urbanization and eco-environment coupling in Jiangsu Province according to the implication and PSR (Pressure State Response) framework of urbanization and eco-environment coupling. Moreover, five typical scenarios during 2.00-2.1. have been simulated and analyzed based on the time serial statistical data during 1.90-2.03 in Jiangsu, which indicates: firstly, there are significant differences between the results and the scenarios, and the five coupling models all have comparative advantages and drawbacks; secondly, in terms of the characteristics and regional development disparities of Jiangsu and the general rule of world urbanization process, this paper reveals that only when either population urbanization model or social urbanization model to be correspondingly adopted, the sustainable development among population, economy, urbanization and eco-environment can be realized.

关键词： urbanization eco-environment system dynamics model simulation Jiangsu Provincel

Variational solution about over-determined geodetic boundary value problem and its related theories

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Science China Earth sciences 2007年第4期50卷 555-562页

作者： YU JinHai1.2.& PENG FuQing3 1.{1. of geodesy and Geophysics,{2., wuhan 430077, China 2.College of Earth Scienc, Graduate University of{2., Beijing 1.0049, China 3 Zhenghou {1. of Surveying and Mapping, Zhengzhou 450052. China 1. institute of {1. and Geophysics Chinese Academy of Sciences Wuhan 430077 China 2. College of Earth Scienc Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. Zhenghou institute of Surveying and Mapping Zhengzhou 450052 China

A new solving method for Laplace equation with over-determined geodetic boundary conditions is pro- posed in the paper, with the help of minimizing some kinds of quadratic functional in calculus of variation. At first, the so-called variational solution for over-determined geodetic boundary value problem is defined in terms of principles in calculus of variation. Then theoretical properties related with the solution are derived, especially for its existence, uniqueness and optimal approximation. And then the computational method of the solution is discussed, and its expression is exhibited under the case that all boundaries are spheres. Finally an arithmetic example about EGM96 gravity field model is given, and the computational results show that the proposed method can efficiently raise accuracy to deal with gravity data. In all, the variational solution of over-determined geodetic boundary value problem can not only fit to deal with many kinds of gravity data in a united form, but also has strict mathematical basements.

关键词： earth’s gravity field over-determined boundary value problem quadratic functional. variational solution optimal approximation