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Description of the older school age boys dental injuries in České Budějovice region and proposal of the health education materials.
TOBOLKOVÁ, Andrea
Thesis deals with the problem of the older school age boys dental injuries in České Budějovice region. The injury means: ?sudden damage of the health by effect of external factors which exceed adaptation options of the human body?. In the sphere of dental injuries the children is the most jeopardized group of population. The most often reason for the children injuries is their imperfect stability. In case of older children and young people there are injuries mostly caused by sport. Teoretical part of my thesis is focused on definition of older school age as well as on anatomy and teeth physiology. The part of thesis also is the enumeration of dental injuries and its treatment. I also mention prosthetic dentistry and the influence of accidents on individual physical and mental health. At the end of teoretical part there is mentioned process of the injured examination, posttraumatic dental hygiene and patient nutrition after teeth accident. Research part finds with the help of questionnaire survey the kinds of dental accidents, circumstances of injuries formation and the influence of accidents on individual physical and mental health in specific age category. The questionnaire survey was evaluated and processed in grafical part of thesis. The part of thesis also is health and educational material which helps to rise the quality of dental hygiene and also contributes to the prevention of dental accidents formation of second degree students at primary schools.
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Small mammals in diet of barn owl in the Eastern Meditarranean
Šindelář, Jiří ; Horáček, Ivan (advisor) ; Anděra, Miloš (referee)
The extensive material of skeletal remains of mammals from a diet of barn owl in the eastern Mediterranean has been processed and evaluated with different techniques of chorological and morphometric analysis. At least 8400 individuals of 45 species of insectivores, rodents and bats were found in our total collection of samples, which represents a significant portion of fauna of the region. We have evaluated a chorological composition of the taphocoenoses and the interregional differences, manifested primarily by differences in the representation of satellite and accessory elements. We found a highly significant impoverishment of the isolated island taphocenoses (Cyprus, Karpathos, partly on Crete), where Cricetidae, Arvicolidae, C. leucodon etc. are missing. On the other hand the essential part of the dominance structure takes up the Rattus rattus, which acts here as an invasive species, significantly more successful than in the ragged continental contexts. The species diversity of the examined samples is positively correlated with the geographic latitude (taphocenoses of the northern regions are significantly richer) and negatively with the island effect and the degree of aridization. The morphometric analysis of the three most abundant species of Soricidae within the studied region showed...
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Optimalization of material flow in automotive industry
Kolář, Tomáš ; Jirsák, Petr (advisor) ; Vinš, Marek (referee)
This master thesis is focussed on optimalization of material flow in an automotive company. First part introduce theoretical background. Automotive industry and its actual trends on global markets. Follows short introduction of the company where project of this thesis was executed. Main theoretical part describes concept of lean management, its tools in practical examples, but it is also focussed on philosophical approach to the work and mindset of the company. Follows the aplication part based on theoretical background. The whole project of this master thesis is focussed on specific area called PC store. At first this area is showed in context of overall material flow. Shortly there are introduced processes and areas where full material packaging flows. Follows deeper analysis and optimalization of PC store itself. There are three approaches of stock and lead time reduction applied. Last part shows the comparison of initial and future state including performed changes.
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HYDROGENATION PROPERTIES OF BALL-MILLED Mg-Ti-C-Zr COMPOSITE
Král, Lubomír ; Čermák, Jiří ; Roupcová, Pavla
The hydrogen storage properties of ball-milled Mg-Ti-Zr-C composite (1.8 wt.% Ti, 1.9 wt.% Zr and 0.2 wt.% C) were investigated. It has been previously shown, that the addition of Ti, Zr and C improved its storage properties. This beneficial effect of additives upon hydrogen storage properties can be explained by catalysis by the particles rich in Ti or Zr located on the surface of Mg grains. They provide effective pathways for the hydrogen diffusion into the MgH2. The morphological and microstructural characteristics were investigated by scanning electron microscopy and by X-ray diffraction. The hydrogen sorption was measured by Sieverts method using Setaram PCT-Pro device. In this paper, sorption behaviour of the composite after ball-milling and after aging on the air was compared. The ball-milled composite adsorbed 3.5 wt.% H2 within 10 min at 623 K. However, hydrogen storage capacity of the composite aged on the air for 7 months remarkably decreased: The aged composite adsorbed within 10 min only 2 wt.% H2 at 623 K and the sorption capacity decreased from 4.7 wt.% H2 to 2.1 wt.% H2.
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INFLUENCE OF LASER CUTTING AND PUNCHING ON MAGNETIC PROPERTIES\nOF ELECTRICAL STEEL M470-50A
Bulín, Tomáš ; Švábenská, Eva ; Hapla, Miroslav ; Ondrůšek, Č. ; Schneeweiss, Oldřich
Electrical steel M470-50A belongs to the most often used materials in electrical machines. Due to this fact, it is desirable to know the magnetic parameters after processing raw sheets into the required shape. Basic parameters of mechanical, electrical, and magnetic properties of the sheets are usually obtained from the producer but the magnetic properties are changing in dependence on additional machining processes. The aim of this study is to describe changes in parameters of magnetic behavior after punching, laser and spark cutting of the original sheets. The basic information of structure was obtained by optical and scanning electron microscopy. The magnetic parameters were acquired from the measuring of magnetic hysteresis loops in dependence on saturation fields and frequencies. The results are discussed from the point of view of applied\ncutting technology with the aim to obtain the best magnetic parameters and consequently a higher efficiency of the final product. Results can be used as input parameters in simulation of the electrical machine.
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Changes in structure and phase composition in the surface of tram rail
Švábenská, Eva ; Roupcová, Pavla ; Schneeweiss, Oldřich
We have investigated structure and phase composition of surface layer of tram rails after long time running and the results were compared with those obtained on the original part of material. Changes due to effects of severe plastic deformation together with thermal shocks by friction process were expected. The information about structure and phase composition was obtained by optical and scanning electron microscopy, X-Ray Powder Diffraction, Mössbauer Spectroscopy and Glow Discharge Emission Spectroscopy (GDOES) and this was completed by microhardness measurements. The results show that the surface layer in comparison with the original material exhibits important changes in grain structure, an increase in microhardness and high content of iron oxide and hydrooxides. According to the depth profile of the chemical composition measured by GDOES there is an increase in carbon content in the surface layer which can be effect of up-hill diffusion.
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HYDROGEN ABSORPTION IN A-Co30Fe55B15
Čermák, Jiří ; Král, Lubomír ; Roupcová, Pavla
Hydrogen solved in amorphous alloys (AAs) influences their magnetic characteristics. AAs are also perspective\nas additives that can improve hydrogen storage kinetic in certain types of ball-milled hydrogen storage\nmaterials (HSMs). Therefore, knowledge of hydrogen solubility and hydrogen sorption kinetics in AAs are of a\ngreat importance for aimed design both AAs with optimal magnetic parameters and HSMs with desired sorption\ncharacteristics. In the present paper, amorphous alloy Co30Fe55B15 (an example of the type a-TM1xTM2y Bz ;\nTM - transition metal) was investigated. Hydrogen concentration c H was measured by Sieverts method in\ntemperature interval from T = 150 °C to T = 350 °C under hydrogen pressure p up to 6 MPa. It was found that\nc H was an increasing function of p and its maximum value was typically 0.5 wt.% H2 at 350 °C and 6 MPa.\nHowever, when the alloy was preliminary hydrogen charged (PHC), the pressure dependence of total c Htot in\nthe first absorption cycle(s) is non-monotonous in dependence on PHC conditions. For the sake of comparison,\nthe same absorption characteristics were measured also in Mg2Ni intermetallic that is a common constituent\nin Mg-based HSMs. Comparing Co30Fe55B15 and Mg2Ni, it was concluded that Co30Fe55B15 shows lower\nhydrogen solubility, but much better absorption kinetics.
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