DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 3-4/2016 str. 57     <-- 57 -->        PDF

a number of automated GNSS tracking stations, which continuously record carrier phase and pseudorange measurements for all GNSS satellites in view. Figure 2 shows the coverage area of ISKI-CORS network, which contains the boundary of the province of İstanbul.
3.2 Model Construction – Izgradnja modela
The objective of this study is to examine the applicability of GNSS and total station integration for determining the position of a point located under the forested area, according to short observation length and the required horizontal accuracies. Two observation stages were conducted simultaneously: (1) GNSS observations (2) terrestrial total station measurements. As has been stated above, the current study also aims to provide an economical and practical survey method to obtain accurate point positioning under the forested areas for forestry applications.
Four points in all were established around the forested area, namely N1, N2, N3 and N4 (Fig.3). Simultaneous observations were achieved from the field site to shorten the observation time, and then, within 15 minutes the GNSS and total station surveys were completed. To compute the coordinates of K, located under the forested area, coordinates of N1 and N2 were determined by CORS RTK GNSS surveys. Coordinates of N3 and N4 were determined using terrestrial measurements from two triangles (Triangle I & III, see Fig. 4). To control the coordinates of K, static GNSS survey was performed during 3-hour observation time.
As is well known and currently used, resection is a method for determining an unknown position measuring angles with respect to known positions. The method involves taking azimuth or bearing angles to two or more objects, then drawing lines of position along those recorded bearings or azimuths. Since the intersection method uses angular