Determination of Survey Boat “Heave” Motion with the Use of RTS Technique

The paper presents analysis of determination of vertical movement of the surveying boat called “heave” with the use of Robotized Total Station (RTS) technique. The classical geodetic Total Station was used for sub-centimeter calculation of water level changes during hydroacoustic measurements on the fragment of Vistula river behind the dam and hydropower in Włocławek in Poland. The power station work causes up to 1.7 m movement of vertical reference water surface in aspect of local bathymetric survey. The experimental, hydrographic surveys on the river were conducted where the water level was changing significantly over time depending on the operational schedule of the power plant. Verified hydrographic data had to be brought to the common water level. To determine the final water level, data on the height of the Robotized Total Station prism positioned on the boat during sounding was considered. The RTS technique with 0.02–0.05 m vertical accuracy proved to be very useful and essential in engineering inland bathymetric measurements.

A Method for Estimating the Area of Damaged Croplands and Woodlands with the Use of Unmanned Aerial Vehicles (Drones)

Growing social demand for access to spatial information spurs the rapid development of measurement methods and systems for registering the results of spatial evaluations and analyses (Kwietniewski 2008). Any assessment of spatial development is carried out on the basis of information obtained from specific sources (Kowalczyk 2007). The main objective of this study was to propose a method for assessing the extent of damage caused by natural disasters to croplands and woodlands with the use of unmanned aerial vehicles (drones). The main aim was achieved through detailed goals, including determination of the causes of natural disasters, description of the field inspection procedure and development of loss assessment principles. The proposed method was verified in selected research sites, and the resulting damage report detailing cropland losses is presented in the study.

A Method for Evaluating and Principles for Developing a Map of the Productive Potential of Agricultural Land

Crop production is a highly complex process. It requires comprehensive knowledge about natural phenomena and agronomic treatments that provide plans with optimal conditions for growth and development. Crop yield is influenced by a variety of environmental factors, including availability of water, temperature and light. The main anthropogenic element in crop production is the shape of the plot which is determined by the land division plan. Farmers also have to undertake the relevant measures to ensure the appropriate soil pH, soil structure, nutrient content and microbial activity. The main objective of this study was to develop a method and principles for evaluating the productive potential of agricultural land, and to compile a map presenting the productive potential of agricultural land. The main aim was achieved through detailed goals. Model evaluation indicators and criteria, the sources of information used in the evaluation process as well as the stages of and principles for developing a map of the productive potential of agricultural land were described. The results of an evaluation performed on a selected research site were presented in graphical form in the Conclusions section.

New Research on Gravity Field in Lithuanian Territory

New research of Lithuanian territory gravity field was started in 2016 with aim to improve accuracy of quasigeoid as well as accuracy of normal heights determined by methods of satellite geodesy. Obtained data could be used in the research of geophysics, geodynamics as well as in performing the precise navigation. Quartz automatic gravimeters Scintrex CG-5 are planned to be used for the survey consisting of 30000 points. Method of gravity measurements was worked out. RMS error of gravity determined with this method does not exceed 60 @Gal. Coordinates and heights of measured points are determined with GNSS using LitPOS network and LIT15G quasigeoid model. RMS error of coordinate determination does not exceed 0,20 m, for normal heights – 0,15 m. Method of gravity anomalies determination and their accuracy estimation was prepared.

A Minimum Size of the Search Cube in the MAFA-ILS Method

The Modified Ambiguity Function Approach – Integer Least Squares (MAFA-ILS) is one of the modern method for the precise real-time GNSS positioning, for many applications such as geodesy or surveying engineering. Contrary to the classic approach, in the MAFA-ILS method the solution is sought in the coordinate domain. However, to obtain a proper solution, the search region cannot be too small. On the other hand, to have an effective solution – in the computational load sense – this region cannot be too big. In this case the determination of the minimum size of appropriate search region is not a trivial task. The paper presents a certain solution of this problem.

Analysis of the Influence of Properties Management in the Region on the Transaction Prices Level of Unbuilt Land Properties – Case Study

This article presents the results of analysis of the influence of selected economic, legal and environmental factors on the level of transaction prices of unbuilt land properties, in two randomly selected districts of the southern Poland. The results of the research allowed extraction of a group of factors influencing the spatial distribution of the average prices of the surveyed properties. They gave also the answer to the question about the extent to which the unit prices are confirmed by the state of properties management in the region. An analysis of the existing state in the selected region based on the analysis of the local market was performed. Furthermore, the conformity of local plans for the studied areas was examined, as well as an analysis of spatio-temporal distribution of transaction prices of real estate was performed. The research has shown that the level of transaction prices on the local real estate markets is related to the real estate management of the surveyed areas. The state of the economy is affected by many factors, most important of which seems to be the location in relation to urban areas and the condition of the access roads. The undertaken tests correspond with the directions of the world research.

Investigation of Vilnius Upper Castle Vertical Deformations

The aims of this study were to to review the monitoring methodology of the vertical deformations and to identify the reasons of deformations that occur in structures of Vilnius Upper Castle, Lithuania. Collected systemized data is processed with mathematical–statistical methods. In order to investigate the state of the buildings, a new cycle of measurements (XIV) was carried out in 2016. Data of all measurement cycles is presented and compared with previous data that was provided in technical reports of measurement cycles (first measurements began in 1968). In order to investigate conditions of the structures, data is presented graphically. When analyzing the graphics, it is possible to investigate changes of the buildings and possible causes of their appearance are presented. Long-term research and results have shown, that all the cracs and crevices that were found during monitoring (1968 to 2016) in Upper Castle’s structures were caused by large and uneven deformations.

Determination of Relation between the Quaternary Sediments and Land Use Dissemination on the Basis of Šventoji River Basin

On preparing of the first management plans of River Basin Districts have been found that diffuse agricultural pol-lution is one of the most important causing factor and the most significant impact on the quality of water bodies. Diffuse agricultural pollution can be from 45% to 80% of nitrate nitrogen pollution load of water bodies. Pollution is transported by water surface and subsurface runoff through sediments from agricultural territories. This article aims at evaluating of relation between the Quaternary sediments and Land use dissemination. The lithological factor (sandy, loamy, argillaceous) of the basin was calculated based on Quaternary map of Lithuania M 1:200000 and Lithuanian river map M 1:50000. The land-use factor of the basin was calculated based on Corine Land cover M 1:100000 using ArcGis software. In order to carry out more thorough analysis of the determination of relation between the Quaternary sediments and Land use dissemination in given territories, sections of 0–50 m, 50–200 m, 200–500 m, 500–800 m, 800–1000 m and >1000 m were established, calculating the distance in meters from the riverbank.

Investigating Recycled Filter Media in order to Remove Fluoride Compounds from Groundwater

In this article, an enhanced recycled filter media for the removal of fluoride compounds from groundwater via filtration process was investigated. Experiments were made to investigate the influence of recycled filter media on removal efficiency of fluoride compounds. The recycled backwash cake based filter media used at Lithuanian water works were inves-tigated in a pilot test-bench constructed for this research in the Water Management Laboratory of Vilnius Gediminas Technical University.

The Horizontal Deformation Analysis of High-rise Buildings

The horizontal deformation analysis of high-rise buildings, quite often is complicated because buildings like chimneys, towers and etc, have complex and asymmetric shapes, consequently there is not always the possibility to apply the method of single points motion analysis. Furthermore, the horizontal deformation analysis is complicated using standard measurement methods like measurements with electronic total stations or optical theodolites. In such case the terrestrial laser scanner could be superior to traditional measurements. However, the terrestrial laser scanner still not widely used to survey building horizontal deformations using high precision measurements. The main aim of this work is to determine the suitability to measure deflections of buildings from the vertical using terrestrial laser scanners and to investigate point cloud data processing. Measurements of horizontal deformation were carried out using the over ground laser scanner and electronic total station. Horizontal deformations of chimneys of thermal power plants were investigated using corresponding methods. Deformation indicators and evaluated measurement accuracies between different methods were compared. Data analysis of terrestrial laser scanning is more complex, time consuming and requires sophisticated hardware resources in comparison with the traditional methods, however results are much more detailed and informative.