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Reflection Detection and Removal From Image Sequences
Hodaň, Tomáš ; Juránková, Markéta (referee) ; Herout, Adam (advisor)
Cílem mé diplomové práce bylo studium existujících metod pro detekci a odstranění odlesků ze sekvence snímků, nalezení jejich omezení a návrh možných vylepšení. Konkrétně jsme se zaměřili na rovinné spekulární povrchy, jejichž vzhled může být modelován superpozicí odrážené a přenášené vrstvy. Prozkoumali jsme především metody využívající vzájemný pohyb vrstev jako hlavní klíč k jejich oddělení. Popsali jsme jejich společný případ selhání, který spočívá v neschopnosti správného oddělení oblastí s nevýraznou texturou ve směru pohybu kamery. Výsledkem našeho úsilí je metoda řešící tento problém. Jejím hlavním přínosem je nový způsob odhadu hran obou vrstev, kdy důraz je kladen na správné oddělení hran zmíněných problematických oblastí. Věnovali jsme se také následnému odhadu barev jednotlivých vrstev, kdy se vedle hran vrstev využívá i odhad jejich hloubkových map, a popsali jsme alternativní přístup ke klasické kvadratické optimalizaci.
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Core-Shell Ceramic Structures Prepared by Thermoplastic Co-Extrusion Method
Kaštyl, Jaroslav ; Pabst, Willi (referee) ; Hadraba, Hynek (referee) ; Trunec, Martin (advisor)
In the doctoral thesis, the bi-layer ceramic bodies with core-shell geometry were prepared by thermoplastic co-extrusion method and for these composite bodies the mechanical properties were studied. For study of co-extrusion and mechanical properties were designed two composite systems. First system ZTA-A combined the dense core ZTA (zirconia-toughened alumina) and the dense shell Al2O3. Second system ZST-Z consisted of porous core and dense shell made from ZrO2 for both cases. In the thesis, the rheology of ceramic thermoplastic suspensions and their mutual influence during co-extrusion was studied. Subsequently, the debinding process and sintering were studied, and based on the optimization of all process steps were obtained defect-free bodies with core-shell geometry. The mechanical properties (elastic modulus, hardness and bending strength) were determined for sintered bodies. To estimate the stress path in the core shell bodies loaded in bending, the relationship considering different elastic moduli of the core and the shell was used. For bodies of ZTA-A system was increased the strength in comparison with monolithic bodies of the individual components. Thus, bodies with high surface hardness of shell from Al2O3 and moreover having high fracture strength in bending were obtained. The effective elastic modulus was decreased for bodies of ZST-Z system up to 25 % in comparison with the elastic modulus of dense monolithic samples. The same effective modulus of elasticity was possible to achieve with core-shell bodies while maintaining significantly higher fracture strength than monolithic porous bodies or pipes.
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Estimation of Fundamental Speech Frequency
Ráček, Tomáš ; Vlach, Jan (referee) ; Vondra, Martin (advisor)
The Bachelor thesis focuses on algorithms with respect to estimation of fundamental speech frequency. First part is introduce to the questions of speech signals and the thesis at this point gives a clue what the core is going to be about. In the second part the nature of speech signal is explained, as well as the process of it’s creation by a person and models for speech generation. In the chapter 3 processing of acoustic signals are described, where pre-processing, segmentation and application of Hamming window on the same acoustic speech signal are included. The next chapter reports on pitch speech frequency signal as a physical magnitude and it's derivation from the pitch period. Furthermore describes, fundamental frequency creation in speech organs, scale range for different people, properties that carries and finally possibilities of it’s usage. Chapter 5 deals with essential principles defining pitch speech frequency in time, frequency and cepstral domain. Chapter 6 contains description of principles, used in situations, where the speech signal is devalued by noise. In the next chapter author describes design and implementation of selected principle. Furthermore, author presents results that have been achieved with this specific principle and compares them to the results of ordinary autocorrelation principle. The final chapter summarises the thesis and discusses about possible further part, extension or improvement of the algorithm.
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Foreigners in the Czech labour market
Melniková, Olga ; Pavelka, Tomáš (advisor) ; Makovský, Petr (referee)
This thesis is focused on the study into the status of foreigners in the Czech labour market. It is divided in two consecutive units, the first of which contains a theoretical basis for the functioning of labor markets (segments of the labour market, the historical context of labour migration in our country and the legislative framework applicable to the economically active foreigners in the Czech Republic). Another section is devoted to analytical exploration of the topic. It is dealt with the structure of foreign nationals (employment offices registered with a valid trade license), by nationality, age, gender, level of education, type of work performed, etc. For the purpose of this research the author comes out of the available data published by the Czech Statistical Office, Ministry of Labour and Social Affairs and other sources. One aim is to present the development of the monitored data in a particular period and its subsequent analysis.
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Study on the chromosome number in the alveolate alga \kur{Chromera velia} by TSA-FISH
VAZAČ, Jan
This thesis is focused on the chromosome-number studies in alveolate alga C. velia. This Apicomplexa-related photosynthetic organism proved to be a unique instrument for the study of Apicomplexa and their unique organelle apicoplast. To better understand the similarities and differences within these two phyla, a further chromosome analysis was needed. The first part of this thesis sums up the present knowledge about ploidy, life cycle and genome organization within C. velia and the close-relative phyla of Apicomplexa and Dinoflagellata. The second part describes our attempt to examine the ploidy and total number of chromosomes in C. velia using fluorescence in situ hybridization. The ploidy of C. velia was successfully determined and we also made a significant progress in the determination of the total chromosome number. (max. 4000 znaků)
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Intrastat in Practice
Fekerlová, Martina ; Komárková, Lenka (advisor) ; Hajdíková, Taťána (referee)
This work focuses on issues of Intrastat and its main goal is to describe the collection and processing of data, sending statistical reports customs administration and the subsequent identification of the most common mistakes and problems. The thesis is indirectly divided into theoretical and practical part. In the theoretical section are described the concepts related to the international movement of goods and Intrastat. Component of practical part is also the methodology of work, which includes research question and ways of getting information. It is about a qualitative research, precisely observations, analysis of documents and interviews in several companies in the Pilsen Region. The resulting data were processed and the result is a description of the most common problems. The thesis includes proposals for solutions to eliminate these fauls.
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Computer simulation of radiobiological effect of oxygen
Havle, Oto ; Knobloch, Petr (referee) ; Felcman, Jiří (advisor)
Exposing a live cell to ionizing radiation can lead to cell inactivation. Oxygen and other chemical substances soluted in the internal environment of a cell participate in various chemical reactions during the chemical stage of the radiobiological process. The thesis is concerned with modelling di usion and reaction processes of the chemical stage. A system of semilinear parabolic partial di erential equations for concentrations of chemical substances involved is derived in three spatial dimensions, including weak formulation. Assuming spherical symmetry, the problem can be reduced to one dimension. Under further simpli cations, existence of solution is proven via Galerkin method. The one-dimensional problem is solved numerically, using nite element discretization. Error estimates and computer implementation are presented.
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Ricinusin {--} a new antimicrobial peptide isolated from the hard tick \kur{Ixodes ricinus}: the third member of the tick histidine-rich defense protein family.
DORŇÁKOVÁ, Veronika
New gene encoding antimicrobial protein (ricinusin) was isolated from I. ricinus. The 405 nt cDNA fragment contained a 135 aa ORF, encoding a 14.5 kDa protein with 19 aa signal peptide. Gen Bank comparison of ricinusin showed weak similarity to a new type of histidine rich antimicrobial protein with unique HEAHEAHEA repeat from Boophilus microplus and Amblyomma hebraeum. The differential gene expression was strongly induced by blood feeding in larva, nymph and adults. The site of differential expression in salivary glands and gut indicates that ricinusin is induced as a part of broad-spectrum immune response. To study the amtimicrobial capacity of ricinusin and its capatibility in clearing Borrelia burgdorferi infections, it was expressed as a His-tagged fusion protein in bacterial expression system. Analysis of the genomic organization of ricinusin gene showed that it is intronless.
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Interest Rates
Holotňáková, Dominika ; Hurt, Jan (advisor) ; Zichová, Jitka (referee)
This thesis is focused on the study of interest rates, It consists of four chapters. The first chapter provides introduction to this issue, presents basic terminology and different method of interest rate process. The second chapter re- presents theoretical one-factor and two-factor models of interest rates, it is mainly aimed at Vasicek, Dothan and Cox-Ingersoll-Ross model, which are used in the practical part. The third chapter is devoted to internal bank policy, describing the most important factors influencing amount of interest rate and credit limit. The last part of the paper is the practical application of one-factor models on real data. At the beginning of the chapter, we describe methods of parameters esti- mation, which are used for individual models. Numerically estimated parameters are inputs for simulations of yield curves by these models. 1
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Production of polyhydroxyalkanoates from waste substrates and their isolation
Grossová, Marie ; Babák, Libor (referee) ; Márová, Ivana (advisor)
The aim of this work is to study the possibility of microbial production of polyhydroxyalkanoates (PHA). PHA can be used as biodegradable materials. Bacterial strain Cupriavidus necator was used for laboratory production of PHA. This bacterium was cultivated in medium with various precursors to produce copolymers of 3HB with 3HV or 4HB. Another part of the work was aimed at cultivation of C. necator on different waste substrates, especially oils, with the aim to achieve the highest production of polymer. Another large part of the thesis is dedicated to isolation strategies of PHA using enzymes. Commercially used proteases – alcalase and pancreatin – can be used with advantages for digestion of bacterial cells. A number of optimization experiments showed that application of proteases leads to enhancement of PHA purity to about 13%. Purity increase up to 90 % was achieved by adding a surfactant, which promotes the solubility of non-PHA forming polymer. This surfactant increases the purity of 20 % when compared to control. The last part of presented work deals with the use of enzyme solution isolated from Bacillus subtilis medium. Its application to C. necator culture led to the yield of polymer at a purity exceeding 95 %. These results could represent the basis for new isolation strategies, which can lead to more efficient yield of PHA.
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