检索结果-南通市图书馆

Architecture and application of integrated spatial information service platform for digital mine

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2011年第S3期21卷 706-711页

作者： ZHANG Jin1, XIAO Jie2.1. College of Mining, Taiyuan University of Technology, Taiyuan 03002., china 2. institute of {2. and geophysics, Chinese academy of sciences, wuhan 43.077, china College of Mining Taiyuan University of Technology Taiyuan 030024 China institute of geodesy and {2. Chinese Academy of Sciences Wuhan 430077 China

Using enterprise GIS platform, spatial databases and modern information technology, building geo-spatial information service platform of digital mine which has the features of the data exchange service, enterprise GIS services, directory services, logging services, is key technology and application infrastructure for digital mine. Based on the support of geospatial information service platform of digital mine, the professional GIS application service adapter can be developed and the application supports related to mining application system can be realized. Using high-resolution satellite remote sensing data, the mine functional partition map and geographic grids can be divided, and the geographic grid parts, status and events of important features of the surface object were investigated and defined. The system architecture and technical characteristics of integrated spatial information service platform were analyzed firstly, which guarantee service ability of digital mine. The methods and applications of functional partition map for integrated management service platform were discussed which are the services scheme of digital mine. The application results indicated that digital mine upgrades and enhances the capability and range of mine surveying and mapping, and is of great significance for guarantee of efficient, green and intensive exploitation of mine.

关键词： platform architecture web services application services digital mine

The GPS-gravimetry boundary value problem

在线全文

学校读者我要写书评

暂无评论

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 43.077, china 2. Zhengzhou Information Engineering University, Zhengzhou 450052. china institute of geodesy and {2. of Chinese academy of sciences Wuhan China Zhengzhou Information Engineering University 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.

General inverse of Stokes, Vening-Meinesz and Molodensky formulae

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2006年第5期49卷 499-504页

作者： CHENG Luying1,2.& XU Houze1 1. institute of geodesy and {2., Chinese academy of sciences, wuhan 43.077, china 2. Xi’an Research institute of Surveying and Mapping, Xi’an 710054, china institute of geodesy and {2. Chinese Academy of Sciences Wuhan China Xi’an Research institute of Surveying and Mapping Xi’an China

The operator operations between the disturbing potential and the geoidal undulation, the gravity anomaly, the deflection of the vertical are defined based on the relations among the gravity potential, the normal gravity potential and the disturbing potential. With the sphere as the boundary surface, based on the solution of the external boundary value problem for the disturbing potential by the spherical harmonics in the physical geodesy, the general inverse Stokes’ formula, the general inverse Vening-Meinesz formula and the general Molodensky’s formula are derived from the operator operations defined. The general formulae can get rid of the restriction of the classical formulae only used on the geoid. If the boundary surface is defined as the geoid, the general formulas are degen- erated into the classic ones.

关键词： spherical harmonics, boundary value problem, general inverse Stokes' formula, general inverse Vening-Meinesz formula, general Molodensky's formula.

Atmospheric gravity Green's functions

在线全文

学校读者我要写书评

暂无评论

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 43.077, 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.

Validating global hydrological models by ground and space gravimetry

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2009年第9期54卷 1534-1542页

作者： ZHOU JiangCun1,2.3, SUN HePing1,2.& XU JianQiao1,2.1 institute of geodesy and {2., Chinese academy of sciences, wuhan 43.077, china 2.Key Laboratory of dynamic geodesy, Chinese academy of sciences, wuhan 43.077, china 3 Graduate University of Chinese academy of sciences, Beijing 100049, china institute of geodesy and {2. Chinese Academy of Sciences Wuhan China Key Laboratory of dynamic geodesy Chinese Academy of Sciences Wuhan China Graduate University of Chinese academy of sciences Beijing China

The long-term continuous gravity observations obtained by the superconducting gravimeters (SG) at seven globally-distributed stations are comprehensively analyzed. After removing the signals related to the Earth's tides and variations in the Earth's rotation, the gravity residuals are used to describe the seasonal fluctuations in gravity field. Meanwhile, the gravity changes due to the air pressure loading are theoretically modeled from the measurements of the local air pressure, and those due to land water and nontidal ocean loading are also calculated according to the corresponding numerical models. The numerical results show that the gravity changes due to both the air pressure and land water loading are as large as 100×10-9 m s-2.in magnitude, and about 10×10-9 m s-2.for those due to the nontidal ocean loading in the coastal area. On the other hand, the monthly-averaged gravity variations over the area surrounding the stations are derived from the spherical harmonic coefficients of the GRACE-recovered gravity fields, by using Gaussian smoothing technique in which the radius is set to be 600 km. Com-pared the land water induced gravity variations, the SG observations after removal of tides, polar mo-tion effects, air pressure and nontidal ocean loading effects and the GRACE-derived gravity variations with each other, it is inferred that both the ground- and space-based gravity observations can effec-tively detect the seasonal gravity variations with a magnitude of 100×10-9 m s-2.induced by the land water loading. This implies that high precision gravimetry is an effective technique to validate the re-liabilities of the hydrological models.

关键词：重力测量水文模型模型验证和空间地面重力变化季节性波动空气压力

Determination of vertical gradient of gravity anomaly with topographic data

在线全文

学校读者我要写书评

暂无评论

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 43.077 , 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.

Improved retracking algorithm for oceanic altimeter waveforms

在线全文

学校读者我要写书评

暂无评论

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 43.077,china 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

Sea level variations in the South china Sea inferred from satellite gravity,altimetry,and oceanographic data

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth sciences 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2.ZHONG Min 1,3 & XU HouZe 1,3 1 State Key Laboratory of geodesy and Earth’s Dynamics,institute of geodesy and geophysics,Chinese academy of sciences,wuhan 43.077,china 2.Graduate University of Chinese academy of sciences,Beijing 100049,china 3 institute of geophysics,Huazhong University of Science and Technology,wuhan 430074,china State Key Laboratory of geodesy and Earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China Graduate University of Chinese academy of sciences Beijing China institute of geophysics Huazhong University of Science and Technology Wuhan China

Sea level variations(SLVs) can be divided into two major components:the steric SLV and the mass-induced *** two components of SLV in the South china Sea(SCS) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced SLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced SLV in the SCS with annual amplitude of 2.7±0.4 cm,which is consistent with the annual amplitude of 2.7±0.3 cm estimated from the steric-corrected *** the inter-annual timescales,the mean SLV in the SCS shows a large oscillation,which is mainly caused by the steric *** trend of mean SLV inferred from altimetry in the SCS is 5.5±0.7 mm/yr for the period of 1993-2.09,which is significantly higher than the global sea level rise rate of 3.3±0.4 mm/yr in the same *** is no obvious trend signal in the mass-induced SLV detected from GRACE that indicates the water exchange between the SCS and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the South china Sea sea level variation

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2.& LU Yang1,3 1. institute of geodesy and {2., Chinese academy of sciences, wuhan 43.077, china 2. Graduate School of the Chinese academy of sciences, Beijing 100039, china 3. Unite Center for Astro-geodymics Research, Chinese academy of sciences, Shanghai 2.0030, china institute of geodesy and {2. Chinese Academy of Sciences Wuhan China Graduate School of the Chinese academy of sciences Beijing China Unite Center for Astro-geodymics Research Chinese Academy of Sciences Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 2.0 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis