Digital levels significantly simplify field work with regards to automated staff reading, measurement corrections and data storage. However, these instruments are subject to a number of influences whose effects can cause errors in measurements. This especially applies to the negative influence of refraction, which is a serious limiting factor of accuracy in precise levelling. It is still necessary to rectify the effects of refraction via professional analysis of levelling conditions and then choose the best methodology of work. It is particularly important to determine the optimal line-of-sight distance, which yields quality results while keeping greater work productivity. The impact of sight distance of a Leica DNA03 digital level on the final results of levelling network was investigated and described in this article.

There is the specific situation in secondary schools regarding students' understanding of the importance of acquired knowledge which they need for the continuation of their education. Therefore, nowadays it is necessary to introduce innovative forms of knowledge acquiring such as blended learning. The intention is to build an adequate model using Mamdani Fuzzy Logic in terms of better motivation of students with higher and lower metacognitive skills for the online part of teaching. The aim of applied Mamdani Fuzzy Logic method is to determine the best ratio of number of logins on the LMS system, test results and time spent on the LMS system that would give the best results at the final testing. The achieved results show that the applied method effectively determines the best ratio of these three variables in order to achieve the best results at the final testing of different groups of students according to metacognitive skills. 