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Vehicle detection in images
Pálka, Zbyněk ; Přinosil, Jiří (referee) ; Krajsa, Ondřej (advisor)
This thesis dissert on traffic monitoring. There are couple of different methods of background extraction and four methods vehicle detection described here. Furthermore there is one method that describes vehicle counting. All of these methods was realized in Matlab where was created graphical user interface. One whole chapter is dedicated to process of practical realization. All methods are compared by set of testing videos. These videos are resulting in statistics which diagnoses about efficiency of single one method.
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Influnce of chemical composition on mechanical properties of LLDPE stretch film
Vojáček, Jakub ; Tocháček, Jiří (referee) ; Poláček, Petr (advisor)
Thesis summarizes the problems of production and use of stretch film. The change of strength, ductility and relative relaxation effect in different times of drawing from role in three weeks was observed. Further, change of strength and ductility due to changes in the rate of deformation, exposure to accelerated aging in a UV chamber and changes in the loading direction were observed. Mechanical tests were realized on a tensile tester, relaxation tests on DMA and crystallinity changes were observed on the DSC. Relationship between chemical composition of stretch film and mechanical and thermomechanical properties were studied. It was found that chemical composition essential for stretch film properties. However, due to the impossibility to distinguish effects of chemical composition and process parameters was impossible to find clear relation describing this relationship.
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Development of method thermoporosimetry polymer powders
Urbánková, Radka ; Salajka,, Zdeněk (referee) ; Kratochvíla, Jan (advisor)
Thermoporosimetry is a technique to determine small pore sizes based on melting and crystallization point depression. The temperature shift was measured by Differential Scanning Calorimetry (DSC). Development of thermoporosimetry was carried out on silica with a well-characterized narrow pore size distribution. Several parameters were studied, which a have a direct influence on melting and crystallization point depression (for example: a quality of the solvent, filling the pores with the solvent, time and frequency of centrifuging, superfluous solvent removal conditions, etc.). The optimum conditions for the thermoporosimetry method were developed using high porosity silica. The optimized experimental conditions found for silica were applied to polypropylene powder with much lower porosity. Several polypropylene powders were synthesized using different polymerization catalysts and their porosity determined. Polymer powder morphology and structure was characterized by standard methods. Powder porosity obtained by thermoporometry, gas sorption, and BET methods was compared.
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Optimizing of Polymer Surface Treatment for Microscopic Examination
Horská, Pavlína ; Poláček, Petr (referee) ; Bálková, Radka (advisor)
Supramolecular structure of eight commercial types of iPP, its blends with poly(L-lactide) (PP-PLLA) and copolymers with ethylene-propylene rubber (PP-EPR) together with four types of polyethylene (LDPE, HDPE) was uncovered and observed in this work. The spherulitic structure of iPP and PE homopolymers and PP copolymers was uncovered by etching of six different solutions of mineral acids with KMnO4 and by dissolution in four selected solvents. The latter was found to be ineffective. The structure of PP-PLLA blends was uncovered only after recrystallization (the change of structure by annealing and cooling rate). The uncovered crystalline structure was observed directly by confocal laser scanning microscope (CLSM) and SEM. Crystallinity together with a size distribution of crystallites was determined by DSC. It was proved that spherulitic supramolecular structure was easy to uncover by chemical etching only for molded samples and for fracture surfaces of injected samples. The efficiency of etchants varied but, generally, the samples with high degree of crystallinity were etched earlier. The etchants containing nitric acid and high content of sulphuric acid uncovered fine details of shperulites with respect to mixtures containing orthophosporic acid. It was also observed that not only the etchant (especially with nitric acid) itself but also its vapors were effective. The structure was revealed later but the appearance was plastic (3D) and the structure was very fine. The supramolecular structure of PP-PLLA blends differed with amount of each component. The ethylene-rubber phase came forth with increasing time of etching while PP spherulites disappeared in PP-EPR samples. CLSM was shown to be very good tool for observing supramolecular structure of studied samples with respect to SEM, which was proved to be entirely unsuitable for polyolefines. DSC is recommended to be performe before uncovering supramolecular structure for basic information about proportion of amorphous/crystalline phase and size of crystallites.
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The Gallery of Brno Grand Prix
Sikora, Zbigniew ; Boleslavská, Yvona (referee) ; Žalmanová, Petra (advisor)
The main task of this thesis was to create an architectural study of The Gallery of Brno Grand Prix based on previous urban study from previous semester works. The proposal is focused on the iconic circuit’s former glory restoration, on providing new content for raceway complex and creating decent and presentable place for the presentation of the rich history of Czech and Czechoslovak motorsport. The result is a study of an object that meets these needs while respecting the historical and morphological values of the place. The building creates new themed attraction and creates the potential for further development of near circuit.
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Synthesis of ceramic powder materials in the presence of the ultrasound field
Kočicová, Pavla ; Bartoníčková, Eva (referee) ; Částková, Klára (advisor)
The thesis concerns the synthesis Ceric Oxide, Samarium Oxide and Samarium doped Cerium Oxide. The theoretical part is focused on the characteristics, applications and possibilities of the Cerium Oxide synthesis. The experimental part describes the precipitation of the Cerium Oxide powder. The synthesis of the powders were proceeded in the normal conditions or in the presence of ultrasonic field. For the purposes of description of the ready powders the x-ray diffraction (XRD) and the raster electron microscopy (SEM) were used. The ceramics were made of the selected powders where the structure was described by SEM, the density by Archimedes´Method and the grain size by grid-line intersect method. Using the precipitation synthesis, the pure powders of Ceric Oxide, Samarium Oxide and Samarium doped Cerium Oxide were prepared. The powder morphology was strongly involved by the pH level and by ageing time. The ultrasound was accelerating the ageing. At the values of pH > 11 the rodlike particles were created. The ageing time and the ultrasound supported the creation of the rodlike particles. The ceramics made of the powder with the presence of the rodlike morphology showed the density up to 97,14% of the theoretical density.
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Crystallization kinetics of PP impact copolymers
Krajčik, Ladislav ; Poláček, Petr (referee) ; Bálková, Radka (advisor)
In this bachelor thesis, the kinetics of crystallization was studied for three PP copolymers with ethylene-propylene rubber after multiple extrusion. The crystallization rate was determined from the diameter growth of spherulites with time. The growth was observed in-situ by polarizing optical microscope (POM). Isothermal melt-crystallization was investigated at three temperatures (135, 140 and 150 °C). The crystallization rate decreased with temperature for all samples and varied among particular samples the most likely due to the different structure (different polymerization technology). The third extrusion has not affected the crystallization rate compared with the first one. The ? and ß structure of PP was distinguished with help of the first order retardation plate together with determination of the types of spherulites. The lamellar thickening near the border of melt was observed for all samples that crystallized at 135 °C for a long time.
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Genetická a morfologická variabilita skupiny \kur{Melampyrum nemorosum}
DRAHNÍK, Petr
Melampyrum nemorosum agg. is very complicated group of hemiparasitic plants. According to the traditional concept, 15 species is distinguished. Recent molecular analyses show a need of critical taxonomic revision of group and a potential importance of ancient hybridization. Analysis of 3 regions of cpDNA (trnTUGU-trnLUAA, psbA-trnHGUG, rpl32-trnLUAG) and 2 regions of nuclear DNA (Agt1 and At103) reveals well supported lineage with limited geographical distribution. Morphology and genome size of genetically supported lineages were compared.
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Genetická a morfologická variabilita skupiny \kur{Melampyrum nemorosum}
DRAHNÍK, Petr
Melampyrum nemorosum agg. is very complicated group of hemiparasitic plants. According to the traditional concept, 15 species is distinguished. Recent molecular analyses show a need of critical taxonomic revision of group and a potential importance of ancient hybridization. Analysis of 3 regions of cpDNA (trnTUGU-trnLUAA, psbA-trnHGUG, rpl32-trnLUAG) and 2 regions of nuclear DNA (Agt1 and At103) reveals well supported lineage with limited geographical distribution. Morphology and genome size of genetically supported lineages were compared.
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