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OTDR optical path analyzer
Šimková, Barbora ; Tomašov, Adrián (referee) ; Dejdar, Petr (advisor)
The aim of this master's thesis was a theoretical analysis of OTDR issues, analysis of OTDR device components, as well as basic parameters of this device. The thesis also includes a theoretical analysis of reflections, scattering, and various types of connectors. In the practical part, a circuit design for OTDR measurement was developed and subsequently implemented. The circuit was realized using the Red Pitaya development board and Koheron laser. Additionally, a circuit for direct method measurement was also created. In the LabView development environment, a program was created, including a graphical user interface. A laboratory task was also designed to provide a basic understanding of OTDR measurement issues.
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Possibility of using EMW radiation for killing biotic pests
Gintar, Jan ; Klečka,, Tomáš (referee) ; Pěnčík, Jan (referee) ; Šuhajda, Karel (advisor)
The remediation of building elements and structures in terms of moisture and sterilization (inactivation) of biotic pests is dealt with quite often in construction practice and in the construction industry itself, and is thus a topical issue. The issue is dealt with by specialized companies that know the use of available technology on the market, or are themselves involved in the development and improvement of these devices. Several methods are known for the removal of moisture and sterilization of biotic pests, with sufficiently high-quality data on the technology used, the suitability of the equipment used, a more detailed description of the application of the methods themselves and the results themselves. The methods themselves, for removing moisture and eliminating (inactivating) biotic pests, must be chosen according to individual requirements, as some methods will be more appropriate (more effective) and some less suitable. For the practice itself, however, it is important that the methods are sufficiently effective and at the same time available to the wider public (their economic side). In my dissertation thesis I focus on the potential of EMW radiation utilization not only for liquidation of biotic pests (fungi, fungi, wood decaying insects), but also elimination or reduction of necessary conditions for survival or development of these biotic pests. Therefore, my work also focuses on the presence of moisture, because moisture is a common factor in the vast majority of problems associated with the occurrence of biotic pests. Due to its intensity, it is one of the less time-consuming method and therefore a more cost-effective (economically) method. The research I conducted at VUT FAST focused on the use of microwave radiation in the control of biotic pests, under conditions that are close to those on real constructions. The use of a microwave method to eliminate biotic pests and at the same time to remove moisture has proved to be advantageous.
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Antenna for mobile high power microwave generator
Kračmar, Leoš ; Láčík, Jaroslav (referee) ; Mikulášek, Tomáš (advisor)
The bachelor thesis deals with the design and practical implementation of a magnetron connected to waveguide as an excitation source for a linear slot antenna array. The goal was thorough acquaintance with the issue of partial parts of designs, verification of calculated parameters using software simulations and practical measurements on manufactured parts of the project. In the first part of the work, it theoretically deals with used components, used parameters and by software design of a magnetron to waveguide transition model with practical measurement. The second part of the work contains calculations and simulations of the design of a linear slot antenna array, which continues by series of practical measurements of antenna properties.
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Liveness Detection of a Hand
Vanický, Jozef ; Kanich, Ondřej (referee) ; Sakin, Martin (advisor)
This thesis solves the security problem of biometric systems which uses biometric data of a hand. It focuses on the absence of liveness detection during verification of a sample by the biometric system. In result this thesis offers to extend the contactless biometric systems by a system of liveness detection, which utilizes specific properties of human skin and its reactions to certain wavelengths of the visible spectrum of electromagnetic radiation. Reactions of the skin on the specific wavelengths of visible spectrum are analyzed and compared with the reactions of inorganic materials which imitates the hand. Outcome of this thesis is a design and implementation of a liveness detection algorithm, which can, based on the analysis of a set of photographs of the human palm, which was exposed to four wavelengths of a visible part of the electromagnetic spectrum, successfully recognize a hand from a counterfeit with an average accuracy rate of 82.20 %.
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Photoimpedace spectroscopy characterization of optical and electrical properties of the photovoltaic cells
Mocharová, Zuzana ; Chladil, Ladislav (referee) ; Novák, Vítězslav (advisor)
Diploma thesis mainly describes the theoretical knowledge of the topic photoimpedance spectroscopy characterization of optical and electrical properties of the photovoltaic cells, which contains development and princip of cells working, material properties of photovoltaic cells, explanation of electromagnetic waves, spectrophotometry and impedance spectroscopy, followed by a discription of the measuring device and used measuring methods. The experimental section for each measurement method describes the steps of setting the program, then the tables with measured values are involeved in some parts and a part of each method are summary graphs of measured values with subsequent evaluation.
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Monocrystalic silicon - optical properties
Kahánek, Tomáš ; Vaněk, Jiří (referee) ; Špinka, Jiří (advisor)
This diploma thesis deals with optical properties of silicon. The main task of the work was to create silicon samples with ohmic contacts. Suitable radiation source was designed to measure absorption edge of monocrystalline silicon. Designed measuring station was realised. Measurements were performed on samples of p-type monocrystalline silicon provided by ON Semiconductor Rožnov. p. Radhoštěm. The absorbtion edge was measured.
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Disposal of Biotic Pests by EMW Radiation
Sobotka, Jindřich ; Klečka,, Tomáš (referee) ; Myslín, Jiří (referee) ; Tomíček,, Oldřich (referee) ; Šuhajda, Karel (advisor)
The possibility of using high-frequency electromagnetic radiation in the construction sector is a common knowledge. Various experiments have been carried out to dry construction materials, or even to destroy biotic pests. However, the majority of these experiments have been executed in laboratory conditions. It means they have been carried out under exact limiting conditions, often very far off those conditions in real building practice. Therefore, this dissertation aims at exploring the possibility of utilizing microwave technology in drying and heating of construction materials, in disposing of biotic pests and sterilizing building materials under real conditions in building practice. The thesis will explain that microwaves are a term given to a part of electromagnetic radiation. Electromagnetic radiation is based on the principle that the radiated energy is absorbed by water molecules present in moist building material. In the mass of the irradiated material, the radiated energy is transformed into thermal energy, where a so-called “motion” of water molecules occurs with the energy then being transformed into kinetic energy. The microwave technology itself offers a very wide range of use, which can be easily achieved, thus making the technology available to use in the future. Part of the experiments and the necessary measurements, too, has been carried out on selected types of building materials in the premises of the Faculty of Civil Engineering of Brno University of Technology. They have been executed under conditions which most closely correspond to the conditions in real buildings. Part of the experiments and the necessary measurements were carried out on particular constructions, by the so-called in situ method. As stated in the conclusion of the dissertation, laboratory measurements and the in situ measurements differ considerably in some cases.
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Modeling of surface waves
Zgabaj, Martin ; Haluza, Miloslav (referee) ; Franců, Jan (advisor)
This bachelor's thesis presents the derivation of basic characteristics of surface waves which includes the dispersion relation, the shape of the wave, the phase velocity, the group velocity and the movement of water particle. Thesis deals with both deep-water waves and shallow-water waves. Derived characteristics are examined in both cases. In the last part of thesis there are specific examples of those two types of waves.
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Measurement of wind oscilatory waves on reservoir
Kotaška, Stanislav ; Pelikán,, Petr (referee) ; Špano, Miroslav (advisor)
This diploma thesis deals with the measurement of wind oscillation waves on reservoirs, especially with regard to the determination of wave properties with a focus on the spectral density. The thesis presents the basics of the theory of creation and propagation of wind oscillation waves, the recherche of measuring devices and a description of the pilot measurement with the processing of measured data in the MATLAB environment using the software tool WAFO. Attached to the CD are sample scripts for data processing from the resistance sensor.
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Parameters of FTTx networks - Quality of services
Winkler, Aleš ; Reichert, Pavel (referee) ; Münster, Petr (advisor)
The main subject of this diploma thesis is to make a proposal to improve the optical access network for the transmission of Triple play services. I would here to the reader clarify method of proposal of optical network. There are described the kinds of optical access networks with parameters, for which we must look by their construction. There are described the modern methods of construction optical network too. In the theoretical part are discussed used architecture of networks too. I met here known standards, which I compared for big importance by their choice. A reason of construction of optical network are services known like Triple play. These services together with their problems and parameters are here discussed too. At the end of theoretical part I listed here measuring method for getting negative attribute distorting the led signal. In practical part the locality witch use the optical signal as the source of information is ordered. These network use unfit connections and has less possibilities than usual and this is the reason, why is the network not able to supply Triple play in requested quality. At first the analysis of ordered network was needed. Situation was complicated by the fact, that it has been prohibited entrance to me. The structure of network and network parts was known and documented by me. I made the proposals to improve this network in practical part. By the first proposal remained original kind of access network FTTB, but used new parts with higher performance. By the second proposal I made the network FTTH, by which it was possible to use the last haul optical cables with treatment and using new elements. It was needed to create solution by flat units. The resulting proposals are here evaluated, compared and cost evaluated. For rejection of access to optical network I did not make measuring, so I made simulation for variant FTTH for getting some parameters negative acting transmission.
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