A consistency analysis of D48/GK and D96/TM coordinates of more than 62,000 cadastral boundary (CB)points in the Mura region, which were determined after 1st January 2008, i.e. according to the new Real Estate Recording Act, is presented. Such an analysis can be realized without any additional measurements being taken, but only by using a high quality transformation model. The country-wide triangle-based transformation, Version 3.0, was used as a reference model. The reasons for the inconsistency between D48/GK and D96/TM coordinates of CB points according to the reference transformation model are low accuracy or gross errors in D96/TM coordinates (GNSS measurements) and D48/GK coordinates (classical measurements). Rather than in direct measurement, D48/GK coordinates are obtained indirectly by using transformation. In that case, the inconsistency is caused by poor quality transformation parameters. In addition to possible low quality tie points, there may be an insufficient number of tie points used, or their inadequate spacing. The inconsistency between the coordinates of CB points could also be caused by some problems in the control network and low accuracy of the reference transformation model. The aims of the consistency analysis are quality control of surveys of CB points and quality control of the triangle-based transformation model. To achieve these aims, independent surveys were carried out at the selected locations within the testing area.
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