National Repository of Grey Literature 42 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Design of a dendrochronological database
Majer, Hugo-Miroslav ; Brůha, Lukáš (advisor) ; Brodský, Lukáš (referee)
The bachelor thesis focuses on the design of a spatial database of tree-ring chronologies. The theoretical part of the thesis describes database systems and the storage of spatial data in relational databases. It also reviews existing databases of tree-ring chronologies and the basics of dendrochronology. The next section describes provided dendrochronological data, which are used in methodical section of the thesis. The methodical section describes the data requirements for the created database, the process of its design and implementation within PostgreSQL/PostGIS. Subsequently, it deals with the creation of functions developed in procedural extension of SQL. The stored functions are used to improve import of data. Afterwards, the design of a data filter in the form of SQL statement is mentioned. The main result of the thesis is a spatial database that meets both data and functional requirements, contains provided data and is connectable to GIS. The thesis concludes with a summary of the achieved results and contributions to the ongoing scientific project. Keywords: spatial database, database design, tree-ring chronologies, PostgreSQL/PostGIS, Procedural Language/PostgreSQL
Feature-based multi-resolution topography
Brůha, Lukáš
A three-dimensional (3D) representation of the topographic surface is an important element in planning, civil engineering and mapping. Many state-of-the-art representa- tions provided graphical, 3D model of entire planet. However, the existing solutions to 3D topographic surface lack the geometric flexibility and accuracy on boundaries with models of other geographic features. Most of the contemporary approaches to digital Earth solutions focus on the visualization performance. The high visual performance is achieved by the use of special data structures optimized for rendering. However, this optimization towards visualization hampers the data management of spatial data, their analysis and distribution. Therefore, the introduced solution reflects on multiple requirements of digital Earth systems. In addition to the visualization performance, the requirements regarding data interoperability, data management and distribution, data analysis and the multiple level of detail (LOD) are considered as essential for the design of the new solution. The topographic surface is central to the proposed method. It provides the defining surface in terms of which other features can be geographically referenced to. Therefore, this work introduces a new, more functional data representation of multi-resolution...
Feature-based multi-resolution topography
Brůha, Lukáš
A three-dimensional (3D) representation of the topographic surface is an important element in planning, civil engineering and mapping. Many state-of-the-art representa- tions provided graphical, 3D model of entire planet. However, the existing solutions to 3D topographic surface lack the geometric flexibility and accuracy on boundaries with models of other geographic features. Most of the contemporary approaches to digital Earth solutions focus on the visualization performance. The high visual performance is achieved by the use of special data structures optimized for rendering. However, this optimization towards visualization hampers the data management of spatial data, their analysis and distribution. Therefore, the introduced solution reflects on multiple requirements of digital Earth systems. In addition to the visualization performance, the requirements regarding data interoperability, data management and distribution, data analysis and the multiple level of detail (LOD) are considered as essential for the design of the new solution. The topographic surface is central to the proposed method. It provides the defining surface in terms of which other features can be geographically referenced to. Therefore, this work introduces a new, more functional data representation of multi-resolution...
Simplification of rivers based on the spatial reduction method
Mazur, Dominik ; Bayer, Tomáš (advisor) ; Brůha, Lukáš (referee)
This master thesis is focused on cartography generalization of a rivers using collapse and partial collapse method with the usage of straight skeleton data structure. The proposed method was designed for large scale maps in geographical view and for medium scale maps in cartographic view (till 1 : 100 000). The thesis is focusing on width of a river as stand alone criteria for generalization decision. The presented solution represents set of a criteria which decides on generalization of a river. The presented thesis also solves problematic situations that exist on a river such as islands, junctions, shoulders or bifurcation. The thesis also includes proposed generalization algorithm which is using straight skeleton data structure. The algorithm is implemented in C++ programming language in Microsoft Visual Studio IDE. The algorithm uses external libraries Qt and CGAL (Computational Geometry Algorithms Library) for functioning. Algorithm results are saved in ESRI geodatabase with the usage of Python 2.7 programming language and external library ArcPy. Water areas from ZABAGED were chosen as appropriate data for testing. Achieved results of generalization are presented on test data for various scales and they are compared with base maps of Czech Republic. Keywords: digital cartography, cartography...
Design of online geo-information system of a pond area with focus on spatial data acquisition and processing
Nekola, Lukáš ; Brůha, Lukáš (advisor) ; Čábelka, Miroslav (referee)
Acquisition of bathymetric data, their processing and subsequent visualization of the achieved results in the internet environment using ArcGIS Online technology, this is the proposed bachelor thesis in epitone. The theoretical background of the thesis, explains the nature of interpolation methods and discusses theit applicability to bathymetric data. The work's methodology focuses on data acquisition, processing and interpolation in ArcGIS Pro software. The individual outputs of the interpolation methods are evaluated and compared. Introducted solution also includes the design of a web map application based on ESRI technology. ArcGIS Online and its components, namely the Web AppBuilder, Survey123 and StoryMaps, were used to implement it. The application is focused on a potential visitor with the intention of fishing on the outskirts of the town of Humpolec, where the pond area of interest is located. It can also be used to support water management. Keywords: online GIS, bathymetry, spatial data acquisiton, spatial data processing
Spatial disaggregation of population data using 3D city model
Kovačka, Vít ; Brůha, Lukáš (advisor) ; Štych, Přemysl (referee)
The thesis studies the use of existing 3D models as a source of information about the volume of buildings, which is further used in statistical modeling of spatial data. Existing approaches to the spatial data disaggregation are presented, including those utilizing three- dimensional data. The method of obtaining volume information is implemented employing ArcPy libraries for multipatch format. Open source PostgreSQL PostGIS database functions were put in use to retrieve the volumes from rasters containing information about the height of the building. Disaggregation, performed with both 2D and 3D data, is evaluated in terms of accuracy, model performance, and the ability of 3D data to replace some 2D data. The proposed calculation methods and model results are critically evaluated. Keywords: 3D data, volume, Prague, disaggregation, modeling, ArcPy, PostGIS, machine learning
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...
Generalization of LOD2 building models using the aggregation method
Měchurová, Kristýna ; Brůha, Lukáš (advisor) ; Pokorný, Tomáš (referee)
Generalization of LOD2 building models using the aggregation method Abstract The thesis proposes and implements a method of 3D building models aggregation. The procedure achieves global optima by the means of mathematic optimization. Buildings are aggregated according to similarity characteristics typical for LOD2, e. g. roof type. Aggregation process is driven by minimalization of volume changes and of the aggregate count. The optimization problem was implemented as a Python script with optional parameters to meet custom demands of a wide range of users. Input data models of buildings are created by the method of procedural modelling. Its outcome is further restructured into form of continuous blocks. Finally, the visualization procedure is designed and implemented to illustrate the results of optimized aggregation of 3D building models. Keywords: 3D GIS, generalization, aggregation, mathematical optimization, procedural modelling
Terrain break-lines detection based on Sky View Factor
Englmaierová, Tereza ; Brůha, Lukáš (advisor) ; Bayer, Tomáš (referee)
Terrain Breakline Detection Using Sky-view factor Abstract The subject of this diploma thesis is to propose the procedure of detecting of terrain breaklines using Sky-view factor. The theoretical part of the diploma thesis first introduces the issue of terrain breaklines detection, which presents the methods known to date and Sky- view factor, which is the focal point of the proposed method. Implementation over real data takes place at four locations in the Czechia (Vítkovice, Hradiště, Strnady and Velenka). Data in the form of raster format is tested. At the end, the results of the proposed method and its verification using two selected methods of field edge detection are presented and evaluated. Achieved results point to Sky-view factor for terrain edge detection. Keywords: terrain breakline, digital terrain model, Sky-view factor, detection terrain breaklines methods
Utilization of ALS data for update of a road network
Kutišová, Tereza ; Lysák, Jakub (advisor) ; Brůha, Lukáš (referee)
Utilization of ALS data for update of a road network Abstract My thesis concerned problematics of automatic detection of communication data from aerial laser scanning. Goal of this method is to identify area of roads - tarmacs as accurate as possible. On its basis are counted attributes of specific parts. In first part of the thesis are summarized known procedures, which are used to deal with the issue and experiences and evaluation of the output of theirs authors. In practical part of the thesis is described procedure methodology, which is based on findings from the literature review. Subsequently, input data and model areas are introduced. In the final parts are described results and compared with the results of authors, who used such evaluation in their work. Key words: airborne laser scanning, digital topographic database, road network, database update

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