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941.
概述了精密单点定位与双差GPS定位的基本原理,采用了Bernese软件中精密单点定位模块与GAMIT软件动态定位模块,处理了加州地震与汶川地震的数据,实现了精密单点定位及双差定位实时监测地震变化。 相似文献
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中国东北漫岗黑土区切沟侵蚀发育特征 总被引:4,自引:0,他引:4
In this study, short-term gully retreat was monitored from the active gullies selected in representative black soil area,
using differential global positioning system (GPS). With the support of geographic information system (GIS), multi-temporal
digital elevation models (DEM) were constructed from the data collected by GPS and used for further analysis. Based on the
analysis of multi-temporal DEM, we discussed the erosion-deposition characteristics within gully and a developing model for
black soil gully area of Northeast China was proposed. The results are: (1) The analysis of the monitored gully data in 2004
indicated that the retreat of gully head reached more than 10 m, gully area extended 170–400 m2, net gully eroded volume 220–320 m3, and gully erosion modulus 2200–4800 t·km−2·a−1. (2) Compared with the mature gully the initial gully grows rapidly, and its erosion parameters are relatively large. The
erosion parameters have not only to do with flow energy, but also with the growth phase. (3) There are significant seasonal
differences in gully erosion parameters. The extension of gully area and width dominates in winter and spring without marked
net erosion while changes mainly occur in gully head and net erosion in rainy season. (4) It is remarkable for freeze-thaw
erosion in the black soil area of NE China. The gully wall of SG2 extended 0.45 m under freeze-thaw effect in 2004, and the
distance of gully head retreated maximally 6.4 m. (5) Due to freeze-thaw action and snowmelt, gully is primarily in the interior
adjustment process in winter and early spring. There are much more depositions compared with that during rainy season, which
can almost happen throughout the gully, while erosion mostly occurs near head, esp. for gullies having a relatively long history
of development. On the other hand, the process of energy exchange with exterior dominates in rainy season. It is considered
that this cyclic process is an important mechanism for gully growth in high latitude or/and high attitude regions.
Foundation: Key Project for National Natural Science Foundation of China, No.40235056; The Ph.D. Programs Foundation of Ministry of Education
of China, No.20030027015; China Postdoctoral Science Foundation, No.20070410482; Doctoral Foundation of University of Jinan,
No.B0620; National Natural Science Foundation of China, No.40672158; Key Subject Foundation Supported by Shandong Province
Author: Hu Gang (1976–), Ph.D and Associate Professor, specialized in soil erosion, environmental evolution and regional planning. 相似文献
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We simulate GPS horizontal velocity field in terms of rotations of crustal blocks to describe deformation behavior of the Chinese mainland and its neighboring areas.31 crustal blocks are bounded primarily by~30 Quaternary faults with distinct geometries and variable long-term rates of<20 mm/a,and 1 683 GPS velocities were determined from decade-long observations mostly with an averaged uncertainty of 1?2 mm/a.We define GPS velocity at a site by the combination of motion of rigid block and elastic strain ind... 相似文献
946.
PENG Lin LIU Yanxiong ZHOU Xinghua WU Yongting 《地球空间信息科学学报》2006,9(2):99-102
IntroductionIn GPS data-processing, the most accurate andpopular method is to solve the unknown parametersbased on a GPS network which includes many GPSsites. This mode is always called network-solution.The network-solution makes use of the spatial geom-e… 相似文献
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HUANG Shengxiang JIN Xiangsheng YANG Baocen 《地球空间信息科学学报》2006,9(2):79-83
IntroductionThere are many factors that affect the precisionand reliability of GPS measuring. Generally, theerror sources can be grouped into the followingthree classes: errors correlated with the satellites(such as ephemeris error, satellite clock error,… 相似文献
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High precision orbit determination of CHAMP satellite 总被引:2,自引:0,他引:2
ZHAO Qile LIU Jingnan GE Maorong 《地球空间信息科学学报》2006,9(3):180-186
IntroductionCHAMP satellite was launched on July 15 ,2000 to study the earth gravity field, magneticfield, and at mosphere/ionosphere . CHAMPmission is managed by GeoForshungsZentrum(GFZ) Potsdam withinternational partners .In-cluding accelerometer ,star … 相似文献
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