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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Zpřesnění průběhu vodních toků z dat leteckého laserového skenování / Location accuracy improvement of watercourses based on airborne laser scanning data

Peterková, Tereza January 2015 (has links)
The object of this thesis is to propose the method of location accuracy improvement and longitudinal profile of watercourses using the data of airborne laser scanning. In the thesis the watercourses are seen as valley lines where i tis possible to use the method of terrain brek-lines detection to determine their location. The proposed method processes DMR in the formo f filter point swarm and i tis based od the intersection of planes approximation the slopes adjoined to the watercourse. Primarily the thesis focuses on narrow watercourses in deeply placed valleys and the method is adapted to it. At the same time the proposed method successfully deals with the different accuracy of the primary estimation of the explored watercourse. The end of the work presents and evaluates the results of the used method and the obtained data of the Labe spring region in Krkonoše mountains.
2

The use and processing of TLS data for purposes of forestry and forest ecology

Trochta, Jan January 2017 (has links)
The use of terrestrial laser scanner in forestry seems to be promising technology for new findings about forest ecosystem together with precise information for forest managers and planners. With new technology comes also new methodology of data acquisition, data processing and presentation of results. In this thesis are proposed methodological aspects of scanning setup if forest with analysis of two main obstacles - terrain and tree stems together with estimation of synergic effect of additional scan and optimal distance of such scan. In the following section software for processing of TLS data from forest environment - 3D Forest - is introduced and briefly described. In the last part original and early attempt of the below ground tree biomass reconstruction and volume estimation using TLS data is presented as a part of coppice forest study.
3

Detekce a izolace útočníků pomocí záznamů NetFlow / Detection and Isolation of Attackers Using Neflow Data

Grégr, Matěj Unknown Date (has links)
This thesis deals with using NetFlow records for detection network scanning. Anonymized NetFlow records from backbone VUT network are used as the source. Based on statistics created from these records, several Bash and Python scripts are implemented. With these scripts it is possible to detect network scanning even in large academics networks.
4

Využití 3D skenování pro přípravu obrábění odlitků součástí parních turbín / Using 3D Scanning for the Preparation of Steam Turbines Cast Parts for Machining

Michalisko, Jan January 2012 (has links)
The technical paper deals with the application of 3D scanning for the preparation of cast machining which is a part of steam turbines manufactured by the Industrial Turbo machinery branch office of the Siemens Ltd. in Brno. There is a theoretic explanation of general terms which relate to the 3D digitization process in the first part. Further in the theoretic part, the used digitization systems TRITOP and ATOS are described in detail. In practical part, the analysis of the current process has been carried out and the alternate process of the cast preparation for a subsequent machining has been suggested. By means of above mentioned systems, the cast has been converted in a digital form and compared with the source CAD module. The comparison results in material allowance check and the suitable setting for a following machining process. In conclusion, the technical economic evaluation of both processes has been carried out.
5

Habitatové preference jelena evropského a jelena siky v Doupovských horách / Habitat preferences of red deer and sika deer in the Doupov Mts.

Löwe, Radim January 2016 (has links)
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.
6

Aplikace matematických modelů pro simulaci hydrologických poměrů na vybraných vodních tocích / Application of mathematical models for simulation of hydrological conditions in selected streams

Kurková, Marie January 2015 (has links)
Flood is a natural phenomenon that occurs at different intensities and irregular time intervals. As to natural disasters, floods represent the greatest direct threat for the Czech Republic. They may cause serious critical situations during which not only extensive material damages are done, but may bring also losses of the lives of inhabitants in affected areas as well as vast devastation of cultural landscape including environmental damages. Important from the viewpoint of the elimination of potential threats and consequences of such events is the information issued by flood forecasting service about the character and size of flood areas for individual N-year flood discharges and specific flood scenarios. An adequate image of depths and flow rates in the longitudinal or cross profile of the watercourse during a flood event is provided by the hydrodynamic model. This is why the information obtained from the hydrodynamic models occupies a privileged position from the viewpoint of the protection of citizens' lives and mitigation of damage to their property. The first study is situated on the river Úhlava in meadows by Příchovice near the town Přeštice. The proposal of flood-protection measures is contained in Territorial control documentation. The documentation was elaborated on the basis of hydraulic calculations and experiences from the flood in August 2002. The mathematical model is practically used in the study of analysis of proposed flood-protection measures. The analysis is based on mathematical simulation of water outflow and water level on the river Úhlava. It is possible to use the non-commercial software Hec-Ras, version 3.1.1., for the simulation itself. One of the points of view of the possibility of using proposed flood-protection measures is total efficiency. The mathematical model is posssible to use as a basis of support for realization of proposed flood-protection measures on the river Úhlava in meadows by Příchovice within the grant programme "Program prevence před povodněmi II" under the control of the Ministry of Agriculture. In the second case the mathematical model is practically used in the study of hydrotechnical analysis of streams in cadastral unit. The analysis is based on matjematical simulation of water outflow and water level on chosen streams. It is possible to use the noncomercial software HEC-RAS for the own simulation. The analysis should be shown on dangerous places in the interest place. The mathematical model is possible of using to use as basis for revaluation of action in spatial plan or for view of the flood-protection measures in the village Mochtín. Basic input into the hydrodynamic models is represented by altimetry data. One of ways to obtain such data is through the method of aerial laser scanning (ALS) from the digital relief model (DRM). This method is considered one of the most accurate methods for obtaining altimetry data. Its bottleneck is however incapacity of recording terrain geometry under water surface due to the fact that laser beam is absorbed by water mass. The absence of geometric data on watercourse discharge area may perceptibly affect results of modelling, especially if a missing part of the channel represents a significant discharge area with its capacity. One of methods for eliminating the deficiency is a sufficient channel recess by means of software tools such as CroSolver. The third submitted paper deals with the construction of a hydrodynamic model using 5th generation DRM data, and compares outputs from this model at various discharges with a model based on the altimetry data modified by using the CroSolver tool. Outputs from the two hydrodynamic models are compared in HEC-RAS programme with the use of recessed data and with the use of unmodified DRM. The comparison is done on the sections of two watercourses with different terrain morphology and watercourse size. A complementary output is the comparison of inundation areas issuing from both model variants. Our results indicate that differences in the outputs are significant namely in the lower discharges (Q1, Q5) whereas for Q50 and Q100 the difference is negligible with a great role being played by morphology of the modelled area and by the watercourse size.
7

Možnosti využití nových metod batymetrie vodních nádrží / Possibilities of use of new bathymetry method of water reservoirs

Kundratová, Františka January 2017 (has links)
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.
8

Calculation of forest stand heights on the basis of airborne laser scanning on the territory of Training Forest Enterprise Křtiny

Procházková, Andrea January 2016 (has links)
This diploma thesis deals with calculation of forest stand heights on the basis of airborne laser scanning (ALS) on the territory of Training Forest Enterprise Křtiny. Point cloud data from ALS were interpolated into digital terrain model (DTM), digital surface model (DSM) and subsequently by subtraction of DTM from DSM into canopy height model (CHM). Inverted CHM was used for detection of tree tops by Inversed Watershed Segmentation; tree tops were identified as local minima. Calculated heights of forest stands were compared with height data taken from Forest Management Plan (FMP) and with data from field survey.
9

Možnosti zaměření prostorového členění malých stavebních objektů / The possible direction of the spatial division of small buildings

BÍSKOVÁ, Jaroslava January 2014 (has links)
The aim of the thesis is to describe and evaluate the use and accuracy of the individual geodetic methods and their development focus for the spatial division of small structures, such as monuments, fountains, statues and other objects. Describes the aforementioned methods and necessary equipment for geodetic measurements from eklimetru at table methods to modern laser scanners. Are described in detail methods of photogrammetry and laser scanning. In the laser scanning is very interesting its rapid development. We already have the possibility to use very advanced technology, so we can obtain three-dimensional images useful mainly for documentation of monuments and other buildings.
10

Přesnost zaměření fasády historického objektu metody, možnosti, podmínky / Accuracy of the facade of the historic building - methods, possibilities, conditions

DVOŘÁKOVÁ, Jitka January 2014 (has links)
This thesis deals with methods of surveying the facade of the historic building. The introductory section is a brief history of measurement and guidelines, as well as various methods are described from oldest to youngest, including their accuracy in targeting the facade. In more detail, a method for scanning and photogrammetry, which is currently the youngest methods used in surveying facades. In conclusion, the evaluation methods in terms of accuracy and usability. The aim is to describe and evaluace different methods of surveying from history to the present, including the necessary instruments and their accuracy.

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