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Possibilities of use of new bathymetry method of water reservoirs
Kundratová, Františka ; Roub, Radek (advisor) ; Hradilek, Václav (referee)
It is essential to measure water depths of rivers, water reservoirs, ponds and lakes from various reasons like hydrologic modeling, monitoring of biotopes, monitoring of sediments or archeologic researches. Hence, the bathymetry techniques for measurements of shallow waters are still evolving. The goal is to find the best method allowing fast and economic mapping of large-scale areas and providing high-resolution data. Currently, the most common method in Czech Republic is probably depth measurement by an ADCP devices, which is a very accurate method, but still time-consuming. On the other hand, airborne laser scanning with wavelength of 532 nm (green laser pulse) has a great potential for shallow water mapping.
This work is focused on the possibilities of use of the airborne laser scanning for bathymetry of rivers and water reservoirs in conditions typical for Czech Republic. The methods of obtaining the bathymetric data are discussed in theoretical part, as well as principles of its operation. In the practical part, two study areas (a part of Vltava river and a Hracholusky dam) were scanned using the laser scanner Riegl VQ-880- G. Digital terrain model (DEM) was created from acquired data of the two study areas. After that the DEMs were compared with DEMs which were created from sonar data. The results of comparison are presented. The aim of this work is to assess the ability of airborne laser bathymetry in conditions typical for Czech Republic and verify the accuracy of this method. This method saves time and economic costs and it has great potential to be usable for future research.
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Detection of Terrain Skeleton Lines based on Laser Scanning Data
Jaroš, Jakub ; Lysák, Jakub (advisor) ; Bayer, Tomáš (referee)
The objective of the thesis is to design a new detection method of terrain skeleton lines from airborne laser scanning data. The theoretical part provides a brief introduction to airborne laser scanning issue. There are presented major principles of the technology and procedures applied to create digital terrain model from laser data. There is also described an application of airborne laser scanning in the area of the Czech Republic in detail and follows an exact specification of key terms of the thesis. From the geomorphology, topography and geoinformatics point of view there are defined especially terms like terrain skeleton lines, breakline, valley and ridge. Literary research consists of the summary of already published method of breakline detection. There are algorithms focused on data processing in form of original point cloud as well as algorithms focused on processing data in the raster form. Primary goal of the theoretical part is to express major principles of already published method of detection. The practical part firstly introduces data that are used further in the thesis. The objective of the thesis is a description of a new method of detection of terrain skeleton lines. The method processes laser data converted into raster form and it is based on the analysis of transverse elevation profile...
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Classification of airborne laser scanning data using information about intensity and width of the recorded signal
Petr, Peter ; Potůčková, Markéta (advisor) ; Kupková, Lucie (referee)
Classification of airborne laser scanning data using information about intensity and width of the recorded signal Abstract One of the basic tasks in analysing airborne laser scanning (ALS) data is filtration of mass 3D point cloud with purpose to create digital terrain model and digital surface model. New scanner generation (so called Full-waveform LiDAR) allows analysing the whole recorded signal. The recorded value of amplitude and signal width accordant with reflectance of different objects differs according to geometry of the objects. Objective of this thesis is to create a methodology for classification of ALS data in settled areas. This methodology will be based on number of reflections, amplitude of reflected signal, recorded signal width and on spatial attributes. At the same time it will be analysed how the parameters of amplitude and signal width are affected by characteristics of estate surface. It means which radiometrical characteristics (e.g. different roof materials) and geometrical characteristics (e.g. different roof inclination) belong to which amplitude and signal width. Basic question of this thesis is if amplitude and signal width are good attributes to improve the quality of filtration of mass 3D point cloud in chosen area and if so, how. Key words: classification, segmentation, LiDAR,...
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The use of straight skeleton for the roof shape reconstruction from the laser scanning data
Ečer, Pavel ; Bayer, Tomáš (advisor) ; Lysák, Jakub (referee)
The objective of this study is to explore the methods used for automatic roof reconstruction so far and on the basis of this analysis purpose a methodology, which uses the geometric structure of Straight Skeleton for an initial approximation of the roof shape. In the first part of this thesis issues of automatic detection and extraction of building roof planes from laser scanning data are explored. Also, the Straight Skeleton is described in detail here and its potential for the construction of hip and saddle roofs is explained. An iterative approach which consists of deleting or moving appropriate points between roof planes using the principles of orthogonal regression is specified as an optimization method. In the second part of this thesis the proposed algorithm was implemented using CGAL (an open source library) and then it was tested on different data sets. In the very end, it is concluded that the use of the proposed algorithm on more complex types of roofs is inappropriate. The excellent results of the optimization of hip and saddle-shaped roof types are highlighted simultaneously.
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Impact of horizontal and vertical pattern of habitats on birds diversity
Schovánková, Hana ; Šímová, Petra (advisor) ; Moudrý, Vítězslav (referee)
This diploma thesis follows up the influence of horizontal and vertical structure of biotopes on biodiversity of bird species of Czech Republic of forest and open sites. Vertical structure model was created from digital model of surface of Czech Republic (1st generation) and digital model of relief of Czech Republic (5th generation). Information about horizontal structure were derived by analyzing aerial imagery. Then single variables were detected from these data. Subsequently, it was analyzed which of these variables and which way influence bird diversity. On both types of sites was found increasing bird diversity with increasing diversity of vertical structure. With increasing horizontal structure, however, bird diversity significantly increased only on open sites. The influence of other characteristics was mostly different on bird diversity of open and forest sites, but, for both types of sites, the positive influence had for example edge density of land cover categories or edge density of height categories. Additional part of this thesis was to explore if vertical characteristics of biotopes could influence prediction of selected bird species. Results was different in forest and open biotopes, nevertheless in both types of sites was found potential use of both horizontal and vertical variables.
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The comparison of digital terrain model sources in GIS for hydrological purposes
Klempíř, Hynek ; Bašta, Petr (advisor) ; Gdulová, Kateřina (referee)
This thesis deals with comparsion of digital terrain models from different
sources processed in GIS for hydrological purposes. The diploma thesis is
composed from several parts. First part sis consist of characteristics related to
watershed and water flow, which are important for the understanding this work. The
thesis also describes digitial terrain model, his creation and methods for obtainig
digitial models. Then, there are described data sources from which is possible to
gain digitial models. Next chapter is dedicated to the coordinate system. The last
parts of this thesis describes drain alghorithms.
Characteristic of this area was collected on experimental watershed Modrava II
with the ESRI ArcGIS Desktop software that would mainly Spatial Analyst and
ArcHydro extensions.
The results of this diploma thesis can be concluded that the free digital terrain
model SRTM 90 is not suitable for small regions with diverse terrain structure. Thereason is a small resolution model. Other terrain models provided free of chargé are
sufficient even for small areas as the selected area of interest. Paid digitial models
can al lbe established for the area of interest as appropriate.
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Assessment of changes in slope topography and soil depth redistribution in relation to different soil tillage technologies
Ureš, Jan ; Kumhálová, Jitka (advisor) ; Novák, Petr (referee)
Water, wind, or tillage-induced soil erosion can significantly degrade soil quality and decrease crop yield from farm fields. Traditionally, the research in soil erosion is mostly focused on water or wind erosion. Recent studies over last two decades, however, point to the importance of tillage operations as a source of soil translocation on hilly agricultural land. Tillage disturbs the soil not only vertically but also horizontally by throwing soil in the tillage direction.
This study was designed to assess the soil translocation effect in topsoil before and after 5 tillage operations by using three different practices, namely mouldboard ploughing (A), chisel plough (B), and disc harrow (C) in the Chernozems region at the Sardice (South Moravia, the Czech Republic).
The influence of different tillage practices on the changes in depth of topsoil was assessed through description of 37 shallow pits - 10 pits was digged out before the tillage operations and then other 27 pits after five tillage operations. The results of the soil survey are based on the evaluation of the stratigraphy of the soil profile where the potential loss of topsoil was determined by a change in transition between the dark Ac horizon and yellow loess Ck horizon and by the type of the transition. Shift of topsoil after five performed operations is in the range of 9-15 cm at the top position of concave-convex slope and 4-14 cm at the top of concave slope. From the results of the experiment are also apparent significant shifts across to each tillage practice (C to A), which are, however, more or less caused by the shape of the slope.
By creating and comparing the DEM for the conducted experiment I managed to learn that the largest transport of soil particles was caused by mouldboard plough. Transport of soil particles was larger in the vertical direction than in the horizontal and moved in the range
of -5 to +13 cm. When undermining by a chisel plough was a significant horizontal shift of soil particles to the sides in the range of -5 to +5 cm. The method of shallow tillage with a disc harrow showed a change of the relief in the horizontal direction also in the range of -5 to +5 cm.
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Topographical data sources and derived topographic attributes for describing the variability of agricultural plot
Ladmanová, Markéta ; Kumhálová, Jitka (advisor) ; Komárek, Jan (referee)
This diploma thesis is focused on examination of effect topography on yield on the field. Theoretical research is given in literary overview and it is focused on sources of elevation data in conditions of the Czech Republic. Further there is given description of topographic attributes, which have influence on crop on the agricultural field.
Practical part of this thesis processed data about agricultural field in Vendolí near Svitavy in East Bohemia. One of aims of this thesis was to compare two sets of elevation data. First set of elevation data was provided by Czech office for surveying, mapping and cadastre, data came from airborne laser scanning. Second set of elevation data was measured by DGPS receiver placed on combine harvester during the harvest. Topographic attributes were derived from these two sets of elevation data with help of tools in software ArcGIS 10.2. In the further process topographic attributes were compared with yield of winter wheat from 2014 to assess relationship between topography and yield. In given data there was found dependence of yield on digital elevation model (higher amount of yield was found in higher elevations). Significant relationship between yield and other topographic attributes has not been proved.
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Habitat preferences of red deer and sika deer in the Doupov Mts.
Löwe, Radim ; Ježek, Miloš (advisor) ; Husinec, Václav (referee)
This master thesis is focused on GPS telemetry of red deer (Cervus elaphus) and sika deer (Cervus nippon) in the Doupov Mts., the Czech republic. Positional data from 14 red deer does and 2 sika deer does was collected during the study period of April 2013 to February 2016. The main aim was to determine habitat preferences of does with the use of the very precise vertical differentiation of vegetation created by air laser scanning of the surface (LiDAR technology). The study examines the dependence of the average maximum height of vegetation nearby positions of does on the time of year and time of day. For the evaluation was used two-way factorial analysis of variance. The highest average height of the vegetation nearby does was found during the day and the lowest during the night. Does of red deer and sika deer occurred in open habitats particularly at night, where they were actively seeking for food and more closed habitats with higher vegetation during the day, where they could hide themselves. Focusing on a period of the year, the height of vegetation in the summer period without hunting was significantly lower than in the summer period with hunting. This could be caused by starting hunting season but also it might be a response to reduced quality of available grass by aging. The two does of sika deer were treated individually. Significant differences were revealed between both does. However they both were occupying habitats with the lowest height of vegetation at night during the rut season.
The gained results can now be used to supplement information about ethology of red deer and sika deer. The comprehensive knowledge of ethology can be directly used in the management of these two species, particularly for hunting efficiency and subsequent reduction of their population numbers, particularly in the case of sika deer. However these results can be directly used in forest management in active protection of forest stands against damage by wild game.
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Traffic Signs Detection and Localisation
Kudláč, Ondrej ; Španěl, Michal (referee) ; Veľas, Martin (advisor)
This thesis aims to design the traffic signs detection and localization system using RGB image and 3D LiDAR data leveraging the the existing solutions. Traffic sign detection is based on the shape analysis. Then, the LIDAR data are used for the localization of previously detected signs. The created solution consists of two main components: the detector and locator, each able to operate independently.
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