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Study of physical properties of Heusler alloys
Beran, Lukáš ; Veis, Martin (advisor)
This diploma thesis is devoted to systematic study of structural trans- formations of Heusler alloys by means of spectroscopic ellipsometry and magneto-optical spectroscopy. Structural transformations in these alloys are induced by different microscopic mechanisms. Obtained experimental results were confronted with theoretical calculations. This allowed the discussion of obtained results and suggestion of their interpretation. In the case of Co- Fe-Si alloys, changes in optical and magneto-optical properties with change of Co-Fe ratio were observer. This was explained by lowering of the gap for minority spins with increasing Fe concentrations. Temperature dependent optical and magneto-optical properties of Ni-Mn-Ga alloy showed the pres- ence of so-called Martensitic transformation from cubic to tetragonal phase. A study of Mn-Rh-Co-Sn alloys did not show a clear dependence of physical properties upon the concentration of Rh and Mn. This was explained by strong strain inside the samples, which distorted obtained results. 1
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Studium fyzikálních vlastností Heuslerových slitin
Beran, Lukáš ; Veis, Martin (advisor) ; Mistrík, Jan (referee)
This diploma thesis is devoted to systematic study of structural trans- formations of Heusler alloys by means of spectroscopic ellipsometry and magneto-optical spectroscopy. Structural transformations in these alloys are induced by different microscopic mechanisms. Obtained experimental results were confronted with theoretical calculations. This allowed the discussion of obtained results and suggestion of their interpretation. In the case of Co- Fe-Si alloys, changes in optical and magneto-optical properties with change of Co-Fe ratio were observer. This was explained by lowering of the gap for minority spins with increasing Fe concentrations. Temperature dependent optical and magneto-optical properties of Ni-Mn-Ga alloy showed the pres- ence of so-called Martensitic transformation from cubic to tetragonal phase. A study of Mn-Rh-Co-Sn alloys did not show a clear dependence of physical properties upon the concentration of Rh and Mn. This was explained by strong strain inside the samples, which distorted obtained results. 1
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Determination of gastropods of the genus Radix, the intermediate hosts of trematodes
Mikešová, Kateřina ; Beran, Luboš (referee)
Lymnaeid snails of the genus Radix are common freshwater molluscs of Europe. Formerly, the following species have been reported from the Czech Republic according to the morphology of the shell: R. auricularia, R. peregra, R. ovata and R. ampla. However, recent studies involving molecular data revealed that species determination based on traditional approaches employing morphology of the shell and gonads can be more complicated, confusing and not fully reliable. The shape of the shell is affected by particular life conditions of the snails and proves to be highly variable. The characteristics that can be found on gonads are dependent on the reproductive phase of the snail, and sometimes also on the presence of trematode larval stages, which can cause parasitic castration. Recently, molecular taxonomy is the most reliable approach, especially when a combination of sequences of mitochondrial and nuclear DNA is used. As molecular analyses are relatively time-consuming and expensive, some authors try to find some additional morphological features that could be used for determination of Radix snails in the field, without the need of demanding equipment. Problems in taxonomy and systematics of members of the genus Radix have a practical point in studies of trematode life cycles. From the view of human and...
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Study of physical properties of nanostructures using magneto-optical techniques
Beran, Lukáš ; Veis, Martin (advisor) ; Mistrík, Jan (referee)
Magneto-optical spectroscopy methods are used to study magnetic pro- perties of materials down to nanometer dimensions due to its high sensiti- vity and non-contact nature. This requires sophisticated experimental setup, advanced technical equipment and precise optical components arrangement. This thesis describes the basic physical principles of magneto-optical Kerr spectroscopy. On the basis of these principles is designed and developed a new, much simpler experimental setup with crossed polarizers. This arran- gement has the same order of sensitivity and accuracy of measurement as commonly used modulation techniques to which it is compared in this work. Finally, this arrangement is applied to the study magneto-optical properties of selected magnetic structures and these properties are discussed. 1
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Vulnerability Management
BERAN, Luboš
This bachelor thesis deals with creation of system for Vulnerability Management. Theoretical part contains explanation of Vulnerability Management and cyclic process OODA. Furthermore differences between penetration tests and Vulnerability Management are described here as well. Examples of databases which are used for tools within Vulnerability Management are given at the end of the theoretical part. Practical part includes testing and examples of used tools. Core of the practical part is creating the sustainable system for Vulnerability Management.
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Taxonomic revision of the genera Anisus in the Czech Republic (Mollusca: Planorbidae)
Zavoral, Tomáš ; Juřičková, Lucie (advisor) ; Beran, Luboš (referee)
The aim of this work is to critically review the anatomical and morphological characters being currently used in the determination of Central European species of the genus Anisus and to confront them with molecular characters. For the molecular analysis mitochondrial genes for 16S rRNA and cytochrome c oxidase - subunit I (COI) were used. DNA analysis showed that known species occuring in the Czech Republic form well distinguishable genetic lines. Subsequent revisions of the anatomical characters of these lines have proven that these characters are due to their variability not suitable for determination, especially for the differentiating of the species A. spirorbis and A. leucostoma. The conchological characters have proven more suitable, especially the ratio of the size of the last and penultimate whorl. With the help of this character, we can safely determine a population within which there are transitional forms in other morphological and anatomical characters.
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The development of the porcelain industry in Karlovy Vary region throughout the 20th century
Beran, Luboš ; Jakubec, Ivan (advisor) ; Szobi, Pavel (referee)
The purpose of this bachelor thesis is to analyse the development of the porcelain industry in Karlovy Vary region throughout the 20th century. Firstly, the theoretical part, the will deal with historic aspect of the porcelain industry, its origin in China, the economic factor, as well as circumstances of its origins in Czech lands, primarily in Karlovy Vary region. The core of the thesis is in the analytical part, where the development of porcelain industry in the 20th century will be presented. In the analytical part author puts an emphasis to the post WWII emigration of German population from Sudetenland and its consequent impact on the porcelain manufacturing, Interestingly enough, porcelain industry was historically located in the area, where lived primarily the German inhabitants. From the collected data regarding the ethnic composition in the first half of the twentieth century it is evident that the population transfer had a negative impact on the whole industry. Furthermore, this thesis portrays the development of the industry in the 20th century, primarily during the period from the end of WWI to the privatization of industry between the years 1992 -- 1994.The thesis concludes that the outflow of German specialists negatively impacted the whole porcelain industry, more specifically in regards to product quality, export to foreign markets and the volume of production.
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Department of transport services and its management
BERAN, Ladislav
The thesis is focused on the analysis of transport services within the railway passenger transport in the Czech Republic. Based on the analytical methods of questionnaire survey, SERVQUAL method and each of the resulting strategies SWOT analysis, the following conclusions: Price is the most important factor in the choice of railway transport; 58 % of respondents are dissatisfied with the situation in the railway sector;RegioJet provides the highest quality services on the market.
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