This paper presents accuracy characteristics of determining the position of corners of building structures with RTN GNSS surveying, using indirect methods of measurement. The studies included the following methods: a point on a straight line, intersection of straight lines and distance-distance intersection. The research experiment analyzed the coordinates of the corners of building structures obtained from the surveys and the mean errors of their position as well as mutual relationships of check measurements, or tie distances. The accuracy analysis also took into account base errors deter- mined in real time. Statistical analysis of these parameters was carried out, as a result of which a distance-distance intersection method was very well rated. For other methods, the results were diversified. The article also emphasizes a need to search for other solutions to modernize the indirect methods of measurement in such a way that their use in RTN GNSS surveys would give results most probable when compared to the real ones.
The error reduction technique, based on inverse transformation, for a shunt active resistance measurement using an ammeter and voltmeter is considered. When computing a corrected reading only multiplicative operations on two measurement results are used, namely squaring and division. The proposed method allows to increase re-sistance measurement accuracy by about two orders of magnitude what has been validated by both theoretical and experimental outcomes.