Paper in Mintech '90: the Annual Review of Int'l Mining Tech & Dev 1990 :67-70
The U.S. Bureau of Mines repeatedly surveyed a grid of monuments over an active longwall mine panel in southwestern Pennsylvania, during a 1-yr period. Both conventional ground surveying techniques and photogrammetry were used. The objective of this investigation was to compare elevation measurements of subsidence obtained from aerial and ground survey methods under dynamic ground conditions. The results of a statistical analysis of the survey data show that the mean of the absolute values of differences between 372 matched pairs of elevation measurements was 0.38 Ft (116 mm) with a 95-pct confidence interval of 0.04 Ft (12 mm). 95 pct of the absolute values of the differences were less than 1.11 Ft (338 mm).
Paper in Mintech '90: The Annual Review of Int'l Mining Tech. & Dev.; 1990, PP. 67-70
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