National Repository of Grey Literature 24 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Automated recognition of selected terrain features from their cartographic representation
Sykora, Matúš ; Bayer, Tomáš (advisor) ; Brodský, Lukáš (referee)
Automated recognition of selected terrain features from their cartographic representation. This diploma thesis is dedicated to automatic classification of selected terrain shapes and their cartographic representation. The main aim of this thesis is to design methodological approach for automatic recognition of terrain shapes (hills and valleys) with the use of Machine Learning (Deep Learning). The first part of suggested method divides rough terrain segmentation into two categories, which will be then classified with convolutional neural network. The second part of the thesis is dedicated to the very classification of pre-segmented terrain shapes using Machine Learning. Both parts of the processing are using photos SRTM30 as an input data. The whole proposed method was developed in Python programming language with the usage of Arcpy, TensorFlow and Keras libraries. Keywords: Digital cartography, GIS, terrain shapes, Machine Learning, Deep Learning, recognition, classification, segmentation
Automatic detection of driving lanes geometry based on aerial images and existing spatial data
Růžička, Jakub ; Brůha, Lukáš (advisor) ; Brodský, Lukáš (referee)
The aim of the thesis is to develop a method to identify driving lanes based on aerial images and existing spatial data. The proposed method uses up to date available data in which it identifies road surface marking (RSM). Polygons classified as RSM are further processed to obtain their vector line representation as the first partial result. While processing RSM vectors further, borders of driving lanes are modelled as the second partial result. Furthermore, attempts were done to be able to automatically distinguish between solid and broken lines for a higher amount of information contained in the resulting dataset. Proposed algorithms were tested in 20 case study areas and results are presented further in this thesis. The overall correctness as well as the positional accuracy proves effectivity of the method. However, several shortcomings were identified and are discussed as well as possible solutions for them are suggested. The text is accompanied by more than 70 figures to offer a clear perspective on the topic. The thesis is organised as follows: First, Introduction and Literature review are presented including the problem background, author's motivation, state of the art and contribution of the thesis. Secondly, technical and legal requirements of RSM are presented as well as theoretical concepts and...
Detection of snow avalanche debris from satellite synthetic aperture radar (SAR) data
Klímová, Tereza ; Kolář, Jan (advisor) ; Brodský, Lukáš (referee)
DETECTION OF SNOW AVALANCHE DEBRIS FROM SATELLITE SYNTHETIC APERTURE RADAR (SAR) DATA Abstract This thesis engages with detection of snow avalanche debris at radar images taken with synthetic aperture radar on Sentinel-1 satellite. The aim is to find method for recognizing places at image where is the snow avalanche debris. A method is based on neural net principle, specifically on using pre-trained model of neural net VGG-19. According to results of neural net, training images are splitted into two cathegories: there is an avalanche and there is not. It is called binary classification. The result is statistical evaluation of success rate compared with other traditional methods. keywords: snow avalanche, Sentinel-1, neural net, VGG-19
Field protocol for in-situ biophysical parameters collection
Šudová, Markéta ; Brodský, Lukáš (advisor) ; Červená, Lucie (referee)
Field protocol for in-situ biophysical parameters collection Abstract The main aim of diploma thesis is to design a unified protocol intended for collecting of in-situ biophysical parameters of vegetation based on an up-to-now published literature as well as on my own experimental measuring. The key for measuring of high- quality field data, that are suitable for a subsequent validation of remote sensing products, is an implementation of unified rules as well as all the phases of data collecting, a recommended preparation before the very measuring, the choice of a sampling scheme and a processing of measured data. Based on an accessible literature the current methods of LAI data measuring were evaluated and the basic protocol parameters were defined. For designing of a proper parameterization of this protocol an experimental field measurement was carried out. A determination of a suitable number of partial measurements within ESU is given by a relationship between the number of partial measurements and MSE value. The sampling schemes stated in a literature as well as my own designed sampling schemes are subsequently tested in order to determine a suitable sampling scheme. Based on achieved MSE values the most suitable sampling scheme that was later verified in field measuring was evaluated. Based on a field...
Snow cover detection from webcam images
Fišer, Jan ; Brodský, Lukáš (advisor) ; Jeníček, Michal (referee)
This thesis deals with the possibility of using webcams as a source of spatial data for snow occurrence. The aim of this study is to propose a suitable method of snow cover detection from web camera images. From a sample of 6 webcams of the Czech Hydrometeorological Institute (CHMI) the snow cover is detected by pixel classification methods. The effect of training file size on the accuracy of classification is examined and the overall accuracy achieved by the SVM method was shown to be 97.46%. This study also aims to propose a system for determining the proportion of snow-covered areas. The algorithm consists of several sub-steps: filtering and registration of images, detection of snow, introduction of a coordinate system, calculation of the size of the surveyed area and the proportion of snow-covered area. The designed model can be used for automatic processing of images for various webcams. The melting curves of the snow cover are generated from the obtained daily values of the snow covered area. The results are validated using data from selected CHMI stations. The proposed and parameterized model confirms the possibility of successful use of webcams as a complement to ground measurement of meteorological stations and for the validation of remote sensing products.
Creating 3D models by a UAV
Marek, Robert ; Štefanová, Eva (advisor) ; Brodský, Lukáš (referee)
Bachelor thesis deals with the utilization of UAV for data collection for photogrammetric purposes. Its goal is to create 3D models from the data used by the UAV. These are processed in selected UAV softwares based on analysis. In addition to the basic principles of UAV photogrammetry, the theoretical part includes a search for appropriate methodology for the preparation and implementation of the flight mission. Data processing took place in the Pix4D, 3DSurvey, and the Reference Photoscan used for general visualization. The final part evaluates the resulting accuracy of the outputs. Selected softwares were compared from 16 different criteria, making the Pix4D software the most convenient for processing UAV data. The aim of the thesis is not only to point out the potential of UAV resources in visualization of spatial data, but also the softwares used for this specific data. Keywords UAV, UAV photogrammetry, 3D model, drone, Agisoft Photoscan, Pix4D, 3DSurvey
Grassland management monitoring based on Sentinel-1 data
Doležal, Jan ; Potůčková, Markéta (advisor) ; Brodský, Lukáš (referee)
The main goal of this diploma thesis was to find and quantify the connection between coherence, entropy, polarimetric angle alpha obtained from Sentinel-1 radar data and grass cutting/pastures. The research was carried out in the area of the Krkonoše national park. To assemble and validate applied methodology, field data was collected 5 times. Hourly rainfall data from Czech hydrometeorological institute was available, but it did not have to be used - no rainfalls were recorded at the time of data acquisitions. Dependence between mowing and the value of coherence has been confirmed. After mowing, median coherence was higher than before mowing. The results were similar to VH as well as VV polarization. Coherence on polygons remained higher after 12-24 days. In total, two different data acquisition geometries (ascending and descending) were examined. The results in both cases were similar. For polarimetric parameters, no correlation between polarimetric parameters and grass mowing or pasture has been confirmed. Keywords: radar, SAR, Sentinel-1, coherence, polarimetry, grass mowing
Creating 3D models by a UAV
Marek, Robert ; Štefanová, Eva (advisor) ; Brodský, Lukáš (referee)
The Thesis uses UAV to collect data for photogrammetric purposes. Its goal is to create 3D models from UAV data in selected software. These are applied based on the analysis of specific UAV-focused software. The theoretical part contains, besides the basic principles of UAV photogrammetry, a search for appropriate methodology for the preparation and implementation of the flight mission. Data processing took place in the Pix4D and 3DSurvey, compared to Agiosft Photoscan, used for general visualization. The resulting accuracy and quality of outputs is reviewed in the final section, where it is shown that UAV-specific softwares show greater accuracy of the model in position and space. The purpose of this research is to point out not only the potential of common UAV in visualization of spatial data, but also the software specific to these data. Keywords UAS, UAV photogrammetry, 3D model, Agisoft Photoscan, Pix4D, 3DSurvey
Forest species determination from satellite data
Launer, Michal ; Kolář, Jan (advisor) ; Brodský, Lukáš (referee)
Forest species determination from satellite data Abstract This thesis examines the species composition of forests from satellite images using the pixel classification. The research was done on 24 forest locations in The Ustecký Region, The Karlovarský Region, The Plzeňský Region and The Central Bohemian Region in the Czech Republic. In this thesis, data from the Landsat-8 and Sentinel-2 satellites from summer season and the Random Forest Classifier method were used. The layer of species composition of forests from map portal LhpoMap was used as reference data. The method of work consisted of a broad literature search to select the most favourable classifier and to choose the most advantageous input parameter values to achieve the highest overall accuracy of the classification. The practical part was focused on creating a software classification process. The accuracy of the individual image values was verified using matrix errors. Based on the literature search, the Random Forest classifier was used to classify the images. Parameter values were used for the Gini criterion, 500 decision trees, and the other parameters were left with default values. The entire classification process was performed in ArcMap and ArcGIS Pro software using Python programming language with the help of the sklearn.ensemble module...
Skin surface water temperatures determination in selected lakes and reservoirs from satellite data
Formánek, Tomáš ; Kolář, Jan (advisor) ; Brodský, Lukáš (referee)
LAKE SURFACE TEMPERATURE DETERMINED BY SATELLITE IMAGES Abstract The aim of this master thesis is to create a method to determine surface temperature of water in lake Osoyoos (LSWT - Lake Surface Water Temperature). It is necessary to know this temperature in order to make easier decisions in a paradigm of global warming processes. Thanks to LSWT it is possible to make a timeline visualisation of temperature development in years. The first chapter deals with a physical definition of how to get thermal information - the basis of remote thermal sensing is measuring of radiance intensity and it's transformation to brightness temperature. This radiation is not only influenced by atmospheric properties but also by local climatic and meteorological conditions, but it is also influenced by the relief. The thesis seeks to create a method for calculating surface temperature of lake Osoyoos located at Canadian-American border. This calculation is based on data provided by ASTER using a split-window method. The method works with the differences in bands of sensing in order to remove atmospheric influences. This thesis contains several charts, graphs and pictures. The final result of this paper is a map of distribution of lake surface water temperatures. Keywords: Thermal remote sensing, land surface temperature, ASTER, TIR

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