GJ - Privredna komora Srbije

Figure 1: Ground plan of set up monitoring system [6]
Observations were performed in different time:
• minutely readings ( every 10 and 30 min),
• hourly readings (every 1, 3, 6 and 12 hours) and
• daily readings (every 24 hours).
The accuracy of the performed observations depended upon incidence, the used time interval of readings and
reception of satellite signals. Maximum accuracy of observations is achieved when using a 24-hour interval.
PROCESSING OF OBSERVATION READINGS
Before accuracy comparison could take place the data gathered in hourly and daily GNSS observations had
to be properly processed. The most accurate are the observations made at 24-hour intervals and are therefore
used as the control segment for observations made in smaller time intervals. The observations done in hourly
intervals had to be adjusted and the input data necessary for accuracy comparison had to be eliminated from
observations made in both time intervals.
Observations made in hourly intervals in ideal conditions gave 24 readings per day, respectively 24 records
of coordinate triplets Y, X , H . When daily observations were used only one triplet of coordinates Y, X , H
was obtained for one day. After the adjustment by parameter variation was made on hourly observations the
most probable value of the coordinate triplets was obtained. At the same time the reduction of made
observations was also carried out thus obtaining one most probable triplet instead of 24 triplets per day.
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