THE LAGOS 11.4 KM BASELINE
Autor: | F. A. Fajemirokun, F. O. A. Egberongbe, O. Fadahunsi, T. Parm |
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Rok vydání: | 1986 |
Předmět: | |
Zdroj: | Survey Review. 28:389-398 |
ISSN: | 1752-2706 0039-6265 |
DOI: | 10.1179/sre.1986.28.222.389 |
Popis: | An 11.4 km baseline has been established for calibration of electronic distance-measuring instruments in Lagos, as well as for research work and for calibration of the triangulation network tied to the African Doppler satellite programme currently in progress. This line is part of the proposed 44 km on the same site on the boundary of Lagos and Ogun States. The baseline was measured with an Aga Geodimeter model 8 using a laser as carrier.Because of higher frequency stability, only the U 1 frequency is made functional, while the remaining three frequencies (U 2–U 4) have been disconnected. In addition, a microwave instrument, Sial MD-60, was employed to produce the coarse measurement. The standard error attained for the baseline was better than 1 ppm.The difference in ground elevation does not exceed 70 m, while towers of 30–40 m high are placed at the terminals of the line. The measuring beam runs well above the treetops, which average 10 min height. Two 40 m meteorological towers were built besi... |
Databáze: | OpenAIRE |
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