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Statistical analysis of interval data
Troshkov, Kirill ; Antoch, Jaromír (advisor) ; Branda, Martin (referee)
Traditional statistical analysis starts with computing the basic statisti- cal characteristics such as the population mean E, population variance V , cova- riance and correlation. In computing these characteristics, it is usually assumed that the corresponding data values are known exactly. In real life there are many situations in which a more complete information can be achieved by describing a set of statistical units in terms of interval data. For example, daily tempera- tures registered as minimum and maximum values offer a more realistic view on the weather conditions variations with respect to the simple average values. In environmental analysis, we observe a pollution level x(t) in a lake at different mo- ments of time t, and we would like to estimate standard statistical characteristics such as mean, variance and correlation with other measurements. Another exam- ple can be given by financial series. The minimum and the maximum transaction prices recorded daily for a set of stocks represent a more relevant information for experts in order to evaluate the stocks tendency and volatility in the same day. We must therefore modify the existing statistical algorithms to process such interval data. In this work we will analyze algorithms and their modifications for computing various statistics under...
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Soil contamination by polycyclic aromatic hydrocarbons from local heating
Šustáček, Jan ; Mikulová, Vlastimila (advisor) ; Jiří, Jiří (referee)
Polyaromatic hydrocarbons (PAHs) are the pollutants of the environment. These dangerous chemical compounds are produced by man and its activities. The source of these pollutants are mainly burning of fossil fuels and biomass, as well as transportation and industrial production. From the literature they were obtained evidence regarding PAHs, their properties and group trends. For the main PAHs was found their relative genetic toxicity and was described mechanism of their effect on DNA. Based on the literature was compiled ranking of fuels with respect to the production of PAHs.
The monitoring of untouched area by industry and transportation. The sampling was done in the surroundings Bušanovice village located in Prachatice district. The samples were taken from surface soil horizon. Samples were taken in 2015 to various remote locations from the center of the village. These samples were analyzed by HPLC technique.
It was found that the largest source of contamination are local furnaces burning solid fuels such as wood and coal. The concentrations of PAHs in the samples was in the range of 0.24 to 19.21 mg / kg dm. These values are considerably higher than was expected and in the European scale concentrations correspond to large cities with heavy traffic or industrial areas.
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Optical communication in ultra violet band
Golubev, Martin ; Hudcová, Lucie (referee) ; Poliak, Juraj (advisor)
This bachelor thesis deals with analyzing atmospheric transmission media properties and performance ratio in ultraviolet band optics beam propagating in Earth's atmosphere. In work are definited a optical phenomenons, their implications and use. Description of atmospheric transmission media analyzes the impact of individual particles in the atmosphere on optical beams. There are described a effect of ultraviolet light on living organisms. Simulations of performance ratio using Matlab and proposal of concrete link of UV NLOS for short range are serve as a basis for further research into this field of optical communications.
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Localization of interesting points in power analysis
Vaněk, Stanislav ; Smékal, David (referee) ; Martinásek, Zdeněk (advisor)
Nowadays there are very high demands on security of cryptographic devices due to the increasing number of exploitation. Because of these reasons it is necesary to know the principles of security and their flaws. This thesis deals with the method of localization of interesting markers in current analysis. The aim of the thesis is to analyze this methods and their potential implementation in practise.
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Application of Neural Networks for Human Face Localization
Libosvár, Jakub ; Řezníček, Ivo (referee) ; Španěl, Michal (advisor)
This bachelor thesis deals with detection and localization of human upright faces in images. At first, there are considered current methods. Then the face detection concept is presented. The thesis is focused on practical implementation of artificial neural network-based face detector designed by H. Rowley. Finally, training process and results of detector are discussed in more detail.
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Analysis of Nanostructures by ToF-LEIS
Duda, Radek ; Král, Jaroslav (referee) ; Mašek, Karel (referee) ; Dub, Petr (advisor)
The presented thesis deals with the utilization of TOF-LEIS analytical method in the area of nanostructure analysis. A new procedure for depth profiling of the elemental composition of the sample, based on the alternate measurement with the DSIMS method, was established. The TOF-LEIS method is able to detect the interface between the layers before its mixing by the ion beam of the DSIMS method. Furthermore, a procedure of TOF-LEIS spektra modification was established to obtain the actual concentration of elements in the sample by reduction of a multiple collision contribution. By comparison of TOF-LEIS spectra with the results received by the DSIMS method the ratio of molybdenum and silicon ion yields was obtained. In the next section advantages of the TOF-LEIS method in combination with XPS during analysis of thermal stability of gold nanoparticles are presented. The mutual complementarity of both methods is shown and final conclusions are supported by electron microscopy images. The final section deals with a newly assembled apparatus for the TOF-SARS analytical method and shows its possibilities regarding the detection of hydrogen on the graphene.
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New Conceptions of Power Pulse Converters Using Extremely Fast Switching Semiconductors Based on SiC
Kuzdas, Jan ; Chlebiš,, Petr (referee) ; Drábek,, Pavel (referee) ; Vorel, Pavel (advisor)
This work deals with high power pulse converters (tens of kW) using new semiconductor devices of silicon carbide (SiC). Firstly the current state of the issue is analyzed. A research in a specific area of high power buck converters with pulse transformer follows. There was a strong emphasis on minimizing size and weight. The design process was focused also on reliability and robustness. To achieve the defined objectives, it was necessary to use the latest available switching transistors and diodes, and an unusually high switching frequency (100 kHz at a power of about 16 kW). Due to the high switching frequency, we achieved small size of pulse transformers and output chokes. An optimization of high-frequency pulse transformer with demand on minimum volume and weight of core and windings represents a separate theoretical part of the thesis. There have been proposed several analytical solutions of optimization problems, the results of which could overlap with the implementation in practice of switching power supplies. The combination of high switching frequency, fast semiconductors and the high power brings various parasitic effects to the power circuit. In the thesis, these parasitic effects are analyzed. Solutions which minimize or completely remove those effects were theoretically designed and successfully implemented, tested and finalized in experimental part of the work. Detailed description of the implementation of functional sample and series of validation measurements are included in the final part.
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Study of Scattering and Polarization of Light in Biological Tissue
Abubaker, Hamed Mohamed ; Hrabovský, Miroslav (referee) ; Číp, Ondřej (referee) ; Tománek, Pavel (advisor)
Tkáňová optika nabývá rychle na významu a přesná znalost optických vlastností biologických tkání je podstatná pro výzkum v biomedicíně i pro kontrolu kvality potravin. Jestliže je vzorek tkáně osvětlen, dochází k mnohonásobnému odrazu světla. V případě postmortem neživých tkání (maso) je rozměr buněk větší než vlnová délka použitého světla. Dochází k Mieovu rozptylu prošlého nebo zpět odraženého světla, v důsledku čehož se objevují různé polarizační stavy světla. Polarizační stavy světla rozptýleného na difúzním prostředí jsou experimentálně zkoumány a modelovány. V práci jsme provedli dva modifikované experimenty: rozptyl polarizovaného světla, které dvakrát prochází vzorkem (vpřed a vzad) a jen světla, které jen prochází vzorkem. Měření rozptýleného světla ukazuje, že dochází k depolarizaci a ke stáčení polarizační roviny, což obojí závisí na orientaci svalových vláken a stárnutí tkání postmortem. Mimo experimentů byl také proveden teoretický popis difúzní biologické tkáně a byla vypočtena radiační přenosová rovnice pomocí modifikované Monte Carlo metody, která zahrnuje polarizační stav světla (PLMC). Je ukázáno, že stupeň polarizace podstatně závisí na optických vlastnostech rozptylového prostředí. Výsledky ukazují, že stav polarizace světla na výstupu závisí na stavu polarizace světla před vzorkem a na optických vlastnostech a tloušťce vrstvy prostředí v průběhu jejího stárnutí. Je také provedena korelace změn polarizace na čerstvosti masa, i popis dynamického chování polarizace při stárnutí masa.
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Evaluation of Selected Software Tools for Modeling the Leakage of Hazardous Substances in Accidents in the Chemical Industry
Hrušková, Veronika ; Martincová, Jana Victoria (referee) ; Adamec, Vladimír (advisor)
The thesis is aimed at the modeling of releases of hazardous substances to the designated software tools. The work consists of three parts. The first part is theoretical, which deals with hazardous substances and their legislation, accidents in industry, physical models of leakage and dispersion of hazardous substances and factors influencing their spread in the air and finally software tools. The second part, experimental, describes some software tools and their subsequent modeling. The third part is devoted to the results of modeling and analysis of selected software tools. The aim of the thesis is to analyze selected software tools for modeling the release of hazardous substances, to compare their explanatory power and potential use.
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Measurement of extinction spectra of optically trapped plasmon nano-particles
Flajšmanová, Jana ; Jonáš,, Alexander (referee) ; Brzobohatý, Oto (advisor)
This thesis deals with the dark-field imaging and the optical spectroscopy of optically trapped plasmonic nanoparticles. The optical trapping and the characterization of a single particle or multiple nanoparticles as well are demonstrated. The number of the optically trapped particles can be estimated from the dark-field scattering intensity. Experiments show the presence of the interparticle coupling among trapped metallic nanoparticles which has not been observed in case of dielectric particles. The scattering spectra of the plasmonic nanoparticles were compared with theoretical models based on the Mie theory and the Discrete dipole approximation.
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