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971.
G. H. Purcell Jr. L. E. Young S. Kornreich Wolf T. K. Meehan C. B. Duncan S. S. Fisher 《Marine Geodesy》2013,36(3-4):255-264
Abstract This article describes the design and initial tests of the GPS portion of a system for making seafloor geodesy measurements. In the planned system, GPS antennas on a floating platform will be used to measure the location of an acoustic transducer, attached below the platform, which interrogates an array of transponders on the seafloor. Since the GPS antennas are necessarily some distance above the transducer, a short‐baseline GPS interferometer consisting of three antennas is used to measure the platform's orientation. A preliminary test of several crucial elements of the system was performed at the Scripps Institution of Oceanography (SIO) in December 1989. The test involved a fixed antenna on the pier and a second antenna floating on a buoy about 80 m away. GPS measurements of the vertical component of this baseline, analyzed independently by two groups using different software, agree with each other and with an independent measurement within a centimeter. The first test of an integrated GPS/acoustic system took place in the Santa Cruz Basin off the coast of southern California in May 1990. In this test a much larger buoy, designed and built at SIO, was equipped with three GPS antennas and an acoustic transducer that interrogated a transponder on the ocean floor. Preliminary analysis indicates that the horizontal position of the transponder can be determined with a precision of about a centimeter. Further analysis will be required to investigate the magnitude of systematic errors. 相似文献
972.
973.
分析比对了GPS单点测速技术与其他已有测波手段的不同,讨论了基于多普勒频移的GPS测速方法,并分析了各类误差对测速精度的影响。分别利用原始多普勒值和导出多普勒值进行了静态测速试验和动态测速试验,将导出多普勒测速结果与RTK(RealTimeKinematic,实时动态测量系统)位置差分测速进行了比测。结果表明,使用静态数据采用高频导出多普勒值测速的精度可以达到亚厘米级每秒,而采用原始多普勒观测值进行测速因接收机型号的不同,结果差异较大;动态测速试验中,采用导出多普勒测速的方法与RTK位置差分测速的符合精度可达cm/s。 相似文献
974.
GPS observation indicates that the Fujian coastal region of China mainland, the region of Taiwan Strait and northern Taiwan island all show a generally homogenous horizontal motion with weak deformation. Historical earthquake record over more than 800 years and modern instrumental data reveal that there is potential seismic risk in and around Taiwan Strait region. After the National Seismic Zoning Map of China (2001) the expected seismic risk in northern part of the Taiwan Strait is lower than that in middle and southern part. The suggested northern route of the Taiwan Strait passage project seems to be relatively save seismically. 相似文献
975.
利用GPS手持机对地质观察点进行坐标数据的采集,通过GPS手持机应用软件(GISOffice、MapSource)将所采集的原始数据传输保存到电脑中,使用Microsoft Office办公软件(Access、Excel)对数据进行整理、应用,或存贮、共享应用于其他地质资料整理. 相似文献
976.
�봨����ǰ��ɽ�����ݴ��ĵؿ��˶� 总被引:3,自引:0,他引:3
????GPS?????????“???????”?????????????????????????????????????????????????????????????????????NW???????????????????????????????????????????????5~6????????????????????2???????????????????????NW????NEE????Щ????????????????????GPS?????????????????????£????????????????????????????????????????????????????????????????α???????????仯????? 相似文献
977.
????????GPS??GRACE??????????????????????????????????????е????????ICE-5G and ICE-3G???????????????????????????????????????????е??????????????????????????????????????????????????仯????????????GRACE?????????????????ICE-5G????????????????????????????????????????????С~20%??????????????????????~40%?????????????????????α???????仯??GPS??GRACE???????????????????????????????????????????????????????Ч??? (~150 km??80%?????) ?????????????????????????~90 km); ????μ?????Ч??????????3.7 × 1020?? Pas ??1.9 × 1021?? Pas (90%?????)???????????????????????????С~20%?? 相似文献
978.
????????????GPS????????????GPS????????е?????????????????????????????????????????С?????????????????????????????ζ???????桢???ζ???????桢??????ζ???????????????????о?????????С??????????????С?????????????С?????????и???????????????????????????????е???????????????С?????????????и??????????????????? 相似文献
979.
王乐洋 《大地测量与地球动力学》2013,33(3):106-110
??????????С????????о???????(??)??????????????????????????????????????????????????????????????????????????????ü???λ??????????????(??)????????????С???????????????????????????????????м???в??????????????????????????м???????????????????????????????????????????????????С??????????????????????????????????????????????????????С???????????С?????????????????????????????????С????????о???????????????????Ч??? 相似文献
980.
???????????????????BP?????緽????????????????????棬?????????????????????????????Ч???????????????????????????????????????????????????????????????????????????????????仯???????????????????????????y?????ж???????????п?????θ?????????£?PSO-BP??????????????÷???????Ч???? 相似文献