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Equivalent circuit realizations of the simple chaotic oscillators
Kobza, Jaromír ; Dostál, Tomáš (referee) ; Petržela, Jiří (advisor)
The aim of this paper is to introduce with basic theory the problems encountered when considering the circuit implementation of autonomous RC chaotic oscillator with nonlinearity. All oscillator prototypes are based on one type of universal oscillator circuit. This circuit is able to generate a lot of attractors on condition of different entrance parameters. The design is based on a mathematical simulation, which includes the generation of electronic circuit values. The work is focused the transformation of these values to operational circuit configuration and simulation in a circuit simulator. The final task is to acquire chaotic attractors. Oscilloscope and spectrum analyser photos will verify the operation.
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Circuits with Modern Active Elements
Axman, Vladimír ; Dostál, Tomáš (advisor)
PhD. thesis is deals about sekond order ARC filters for cascade synthezis of Active filters. Here are presented new configurations of second order filters with current conveyors usable for higher frequencies and new second order filters with current conveyors usable for electrical tunable filters. In PhD. Thesis are presented schematics and equations for new sekond order filters. There are presented also practical realizations of these filters and basic measure results.
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Current Feedback Circuits for Analog Signal Processing
Stehlík, Jiří ; Bartoň,, Zdeněk (referee) ; Dostál, Tomáš (referee) ; Musil, Vladislav (advisor)
This dissertation thesis deals with design of new functional blocks usable in area of analogue signal processing, focusing on sensor signal processing. Versatility of these circuits will find applications in programmable analogue array structures that will be possible to control and configure via a digital signal. Hereby build-up array would be fully a reconfigurable digital control system for sensor signal processing and usable for a wide range of different sensors. It offers possibility to build-up a control code for each specific sensor system, with which it would be possible to achieve optimal results of the entire system and consequently place the system on a chip. The presented programmable array is designed from configurable analogue blocks. The current feedback circuits, which in a suitable configuration can operate in voltage or current mode, are used here. This allows to achieve very good results in the systems with very low power supply, which is closely associated with mobility and autonomous behavioral (that are very important and observed parameters today) of the entire sensor-based framework. The work deals in detail with particular blocks, which are described theoretically and evaluated for using in the programmable analogue array. Design of the structure of programmable analogue array as well the use of these circuits in the part of whole system (that will be realized on a chip) are presented at the end of this thesis.
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Active Frequency Filters for Higher Frequencies
Fröhlich, Lubomír ; Dostál, Tomáš (referee) ; Biolek, Dalibor (referee) ; Sedláček, Jiří (advisor)
This thesis deals with the synthesis and optimization of frequency analogue filters with modern active elements usable for higher frequencies. The thesis is divided into three parts, the first part deals with the problematic concerning Leap-Frog combined ARC structure. Due to a difficult design, this method is not described in a detail and used in practice, although it shows e.g. low sensitivity. Firstly, a complete analysis of individual filters was made (for and T endings) and consequently these findings were used during implementation of this method to NAF program. Finally, samples of real filters were realized (for verification of functioning and correct design). Another very interesting topic concerning filters is usage of coupled band-pass for small bandwidth, where it is necessary to solve the problems concerning ratio of building elements values, but also price, quality, size of coils, sensitivity, Q factors, coefficients etc. That is why in practice a coil is very often substituted with other equivalent lossy and lossless blocks which create ARC filters structure. The design and the possibility of usage of lossy grounded elements were described here (such as synthetic inductors, frequency dependent negative resistor). Some parts of the design are individual computer sensitivity analysis, setting of usage and quality comparison of individual lossy grounded blocks. Besides, a program for these elements was created, it is useful for a quick design and depiction of transfer characteristics. The third part deals with the usage of tuning universal filters consisting three or more operational amplifiers, which secures its universality and possibility to create different kinds of transfer characteristic. In practice, Akerberg - Mossberg and Kerwin - Huelsman - Newcomb are the most used types of filters. These were also compared with less common universal filters. In the end, the possibility of digital tuning of universal filter with the help of digital potentiometers for filters of 10th order and frequency around 1 MHz was shown.
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Economics Efficiency of Thermodynamic Heating
Balga, František ; Dostál, Tomáš (referee) ; Luňáček, Jiří (advisor)
This master thesis intents on analysing of economic efficiency of the investment project. Theoretical part of the thesis describes particular periods of the investment decision, what compromise a definition of more types of investments, investment projects and their classification. At the practical part of this thesis is applied the theoretical knowledge to evaluation of the planned investment, then is analysed the most profitable of the evaluated alternates and the last step is to propound next measure for the succesful realization of the project.
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Construction RNAV instrument departures for runway 03C at the Kunovice airport
Dostál, Tomáš ; Vosecký, Slavomír (referee) ; Veselý, Petr (advisor)
This master´s thesis deals with RNAV-1 departure routes for runway 03C at the Kunovice airport. Suggested routes are linked to the new RNAV-1 routes in TMA Brno. RNAV SID maps and construction of one of the departure track are also done and described in this master´s thesis. Beyond design of RNAV-1 routes are also analyzed influences and factors in the master´s thesis that affect the construction of these routes. Construction of RNAV SID routes are based on the knowledge and shortcomings conventional routes that are resulted from the analysis of the current departure routes at the Kunovice airport. In the second part of the thesis is submitted 3 variants of departure routes for Kunovice airport.
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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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Active electrical filters based on switched-capacitor circuits
Třeček, Stanislav ; Dostál, Tomáš (referee) ; Brančík, Lubomír (advisor)
This thesis deals with concept of universal frequency filter by application of a switched-capacitor functional block. The concept is based on the theory of switched-capacitor circuits and the theory of a design of classical frequency filters. The printed circuit board was designed based on the filter connection developed by using a software Eagle. The filter was implemented as a laboratory product. This product has been revitalized and the frequency response of all types of filters has been measured. The measured parameters were compared with the parameters set out in the technical documentation of functional block.
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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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