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Carbon dynamics in the chernozem region after half a century of intensive cultivation
Juřicová, Anna ; Chuman, Tomáš (advisor) ; Dostál, Tomáš (referee) ; Maerker, Michael (referee)
Soils are vital for global food security and recently they have also received attention as a tool potentially mitigating climate change due to their ability to store large amounts of carbon (C) and provide other vital non-productive functions. However, several forms of degradation threat these functions. In agricultural soils, the decline of soil organic carbon (SOC) and soil erosion are two of the degradation processes. Soil erosion laterally redistributes large amounts of SOC in hilly agricultural landscapes. Lateral fluxes further impact the SOC storage in soils and indirectly modulate the vertical C fluxes between the terrestrial sphere and the atmosphere. The aim of this thesis is to investigate the long-term (> 50 years) regional SOC changes and analyze the impacts of soil redistribution in C dynamics in a hilly agricultural landscape. We consider soil redistribution via water and tillage as the main erosion agents. The study uses a comparison of recently resampled and legacy data from historical monitoring (the 1960s) together with coupled erosion and C dynamics modelling using the SPEROC-C model. The study is conducted in the chernozem region, south Moravia, the Czech Republic. Our results showed that the change in SOC content tends to be positive after more than 50 years. Moreover,...
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Spatial interpolation and soil erosion modeling
Bek, Stanislav ; Ježek, Josef (advisor) ; Segeth, Karel (referee) ; Dostál, Tomáš (referee)
The doctoral thesis deals with selected methods of spatial interpolation and their applications to numerical modeling of the earth's surface, in particular soil erosion. The first part contains the description of the studied methods. Firstly and foremost, the method called regularized spline with tension (RST) is introduced. It has proven to be useful in interpolating elevation data. In the thesis, RST is presented in depth with the derivation of its radial basis function and its links to kriging. Further on the mathematics of digital terrain models and the tools for terrain geometric analysis are covered. The following chapter deals with the description of the soil erosion process and of the selected erosion models. The second part of the thesis summarizes five of the author's research articles which include applications of the described mathematical methods. The first two articles are devoted to the problem of elevation data interpolation and the building of digital elevation models. They deal with the optimization of the RST method for particular input data and target erosion models. The third article analysis the spatial structure of the soil data and the pedogenesis of the Žofínský prales natural forest. The last two articles deal with the spatial properties of heavy rainfalls and the mapping of...
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Development of monitoring application for a production cell workspace with SICK scanners
Dostál, Tomáš ; Kovář, Jiří (referee) ; Andrš, Ondřej (advisor)
This thesis is about scanners of SICK company and monitoring methods in workspaces. Next in this thesis is described implementation of monitoring methods in robotic industry. Objective of practical part was design, implementation and to test application created in LabVIEW for monitoring workspaces. Created application contains choice of use serial communication with scanner SICK PLS 101-312 or possibility to create simulation of monitoring workspace. In conclusion both choices are tested and evaluated.
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Spatial interpolation and soil erosion modeling
Bek, Stanislav ; Ježek, Josef (advisor) ; Segeth, Karel (referee) ; Dostál, Tomáš (referee)
The doctoral thesis deals with selected methods of spatial interpolation and their applications to numerical modeling of the earth's surface, in particular soil erosion. The first part contains the description of the studied methods. Firstly and foremost, the method called regularized spline with tension (RST) is introduced. It has proven to be useful in interpolating elevation data. In the thesis, RST is presented in depth with the derivation of its radial basis function and its links to kriging. Further on the mathematics of digital terrain models and the tools for terrain geometric analysis are covered. The following chapter deals with the description of the soil erosion process and of the selected erosion models. The second part of the thesis summarizes five of the author's research articles which include applications of the described mathematical methods. The first two articles are devoted to the problem of elevation data interpolation and the building of digital elevation models. They deal with the optimization of the RST method for particular input data and target erosion models. The third article analysis the spatial structure of the soil data and the pedogenesis of the Žofínský prales natural forest. The last two articles deal with the spatial properties of heavy rainfalls and the mapping of...
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Fully-Differential Frequency Filters with Modern Active Elements
Langhammer, Lukáš ; Dostál, Tomáš (referee) ; Štork, Milan (referee) ; Jeřábek, Jan (advisor)
Tato disertační práce se zaměřuje na výzkum v oblasti frekvenčních filtrů. Hlavním cílem je navrhnout a analyzovat plně diferenční kmitočtové filtry pracující v proudovém módu a využívající moderní aktivní prvky. Prezentované filtry jsou navrženy za použití proudových sledovačů, operačních transkonduktančních zesilovačů, plně diferenčních proudových zesilovačů a transrezistančních zesilovačů. Návrh se zaměřuje na možnost řídit některý z typických parametrů filtru pomocí řiditelných aktivních prvků, které jsou vhodně umístněny do obvodové struktury. Jednotlivé prezentované filtry jsou navrženy v nediferenční a diferenční verzi. Velký důraz je věnován srovnání plně diferenčních struktur s jejich odpovídajícími nediferenčními formami. Funkčnost jednotlivých návrhů je ověřena simulacemi a v některých případech i experimentálním měřením.
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Filtering structures for fotovoltaic power stations
Hruška, Petr ; Dostál, Tomáš (referee) ; Petržela, Jiří (advisor)
This thesis is dedicated to an issue of vibration of photovoltaic panels, which manifests itself primarily in the acoustic field. From the photoelectric effect is gradually getting through photovoltaic cell, panel, string, power plant to define the causes of the vibration. The aim of the work is to design electrical low pass filter that suppress disruptive elements, which prevents audible vibrations of panels and the whole system of photovoltaic power plants.
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Class D stereo audio power amplifier
Kazelle, Kamil ; Dostál, Tomáš (referee) ; Brančík, Lubomír (advisor)
The content of this project is design of stereo audio amlifier working in class D with output power 2x20W. Project includes also a design of preamplifier and power supply. This project is divided into the four parts. In first part the theory and problems of amplifiers working in class D is resumed, in the second the designed circuits are dicussed, in the third the results of simulations in the program PSpice are presented and the last part of project describes the realization and presents the results of measurements.
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Application of the syntetic blocks in the electronic circuit synthesis
Labudík, Marek ; Dostál, Tomáš (referee) ; Petržela, Jiří (advisor)
n project is investigated synthetic coils and FDNR, circuits are first simulated in a snap, which I obtained the graph of the input impedance at the frequency and formula to calculate the impedance. The results of this simulation were used for the simulation program PSPICE, the districts where I was compared with the equivalent circuit, which I design on the formula of the snap. Some of the investigated synthetic and FNDR coils were then used for simulation of the oscillators.
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