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Mysterium Hoericense. The Transformations of the Memory of a Place in the 19th and 20th Century
PALKOVIČ, Jan
The submitted work deals with Passion plays at Hořice na Šumavě (in the district of Český Krumlov) since their origination in 1816, over their temporary decline until their restoration in 1993. It briefly describes the historical development and the contents of the story put on stage, however, the main exploring attention is paid to the memory of a place and cultural expression as a means of showing identity for the German and Czech inhabitants of Hořice na Šumavě. Apart from written sources, regional literature published by Sudeten Germans was used as well as oral history techniques. The aim of these efforts was to document the changes of cultural landscape and social structure of the Sudetenland as a result of post-war power pressure.
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Evaluation of lenght of the Fabry-Perot cavity with ultra-low expansion spacer with optical frequency comb
Šmíd, Radek ; Čížek, Martin ; Číp, Ondřej
The ultra-low expansion materials play a crucial role in laser stabilization and they are essential for laser stalibization. Blocks made from ultra-low expansion material are used as a base for precise interferometric measurements and in AFM microscopes. In our experiment we have monitored the free spectral range (FSR) changes and absolute length of a Fabry-Perot cavity (FPC) with a spacer made from an ultra-low expansion ceramics (Zerodur) with the expansion coefficient (CTE) of 2.8 • 10-8K-1. Experiment was carried out in the vacuum chamber at the pressure as low as 1 O'5 Pa. A fiber based femtosecond mode-locked laser with 100 MHz repetition frequency and central wavelength of 1550 nm was locked to a GPS disciplined crystal oscillator with a short term stability better than 10"12 and long term stability controlled by GPS clocks. An auxiliary tunable DFB laser diode was locked to a certain optical mode of the FPC. A beat-note signal from optical mixing between the laser and a stabilized femtosecond frequency comb is detected and processed. The absolute optical frequency of this mode is defined by saturation to acetylene cell. The FPC spacer of Zerodur material of 175 mm length was analyzed during the temperature cycling process from 22 - 35°C. Measured CTE of the spacer material was (0.069 ± 0.005) • 10-6K-1. Material exhibited hysteresis in the spacer length up to 8 nm during cycling process.
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Study of chemical processes in Titan atmosphere
Klohnová, Karolína ; Grossmannová, Hana (referee) ; Krčma, František (advisor)
The bachelor’s thesis deals with study of chemical processes in Titan atmosphere simulated under laboratory conditions. The abnormal glow discharge as a for-step for gliding arc discharge was used for the plasma generation in nitrogen-methane gas mixture corresponding to the Titan atmosphere composition. The optical emission spectroscopy was chosen as the basic plasma diagnostic method. The theoretic part of thesis describes briefly history of Titan atmosphere studies including the last space craft obtained results. Later, the fundamental properties of plasmas including their diagnostics are given. The general components determined in Titan atmosphere include N2, CH4, H2 molecules as well as a suite of lower weight hydrocarbons including HCN, C2H2 and C2H4; some traces of higher hydrocarbons and amino acids were determined, too. The electrode configuration corresponding to gliding arc arrangement with interelectrode gap of 2 mm was used with high voltage power supply giving power up to 300 W. Plasma was generated in the nitrogen-methane mixtures (0.5 – 2.5 % of methane) at atmospheric pressure. Both gases had purity better than 99.999% and all system was evacuated before measurement to suppress oxygen traces. Optical emission spectra were taken in dependence of applied power and gas mixture composition. Nitrogen and CN radical spectra as well as atomic lines of hydrogen and carbon were identified in the spectra. The vibrational temperatures of 2300 - 8000 K were determined from the spectra of nitrogen second positive, CN violet and C2 spectral systems. Rotational temperature calculated from nitrogen second positive and CN violet 0-0 bands varied in the interval of 1200 - 4800 K depending on the experimental conditions. The obtained results were submitted as a part of paper into international journal. The obtained results maybe used as a fundament for the future study of Titan atmosphere using also other discharge.
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Personality, creativity and complexity of thought
Chadimová, L. ; Urbánek, Tomáš
Presented study introduce the correlation of creativity, personality and cognitive complexity. The structure of cognitive processess has been great topic since the turn of 20th century. The research on cognitive styles have brought many new findings on the interconectedness of personality and cognitive processes such as perception, thinking and decision making, memory etc. Theories of cognitive complexity represent one contribution of this period, which aims on how are the cognitive processess structured, how this structure affects the effectivity of decision making and how it’s affected by different internal or external factors such as sex, age, \npersonality, social context, time pressure etc . In the first part of our research we conducted an analysis of \ncorrelation between divergent thinking factors and cognitive complexity measures following the approach of P. \nSuefeld and P.E. Tetlock. Figural and verbal fluence, flexibility, elaboration and originality were measured by \nsubtests Torrance test of creative behaviour and Guilford Alternative uses test. Cognitive complexity was scored \non the Paragraph completion test data following the Integrative/Conceptual complexity scoring manual (Baker-Brown et al., 1992). In the second part of study we conducted correlation study of cognitive complexity and Big Five personality traits (measured by Czech version of NEO-FFI by Hřebíčková & Urbánek, 2001). The article gives a summary of main findings of our studies and briefly sketch out the questions and hypotheses for future research on the complexity of thought.
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Second sound as a tool to study quantum turbulence generated by superflow of He II
Varga, Emil ; Skrbek, Ladislav (advisor) ; La Mantia, Marco (referee)
Second sound as a tool to study quantum turbulence generated by superflow of He II Abstract Liquid helium bellow 2.17 K at saturated vapour pressure becomes superfluid. Hydrodynamics of such liquid is well described in terms of two-fluid model. Superfluid helium is also capable of developing turbulent flow, called quantum turbulence, through randomization of distribution and orientation of vortex lines. Quantum turbulence in superfluid helium generated by mechanically driven pure superflow was studied by measuring the vortex line density in 10×10mm2 square channel using the attenuation of second sound technique. Agreement with results predicted by Vinen's equation was found in steady state. For decaying turbulence, agreement with Vinen's equation holds only for low initial vortex line densities and tends to develop a region where the time dependence of the decaying vortex line density appears ex- ponential. In course of this work new second sound sensors were made and tested. 1
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Measurement of contact stress in a self-oscillating model of human vocal folds
Horáček, Jaromír ; Bula, Vítězslav ; Veselý, Jan ; Radolf, Vojtěch
The contribution presents in vitro measurement of contact stress in the artificial vocal folds made of a silicon rubber excited by airflow with synchronous registration of the flow induced vocal fold vibrations using a high speed camera, measurement of subglottal dynamic and mean air pressure and the generated acoustic signal. The measured maximum impact stress, maximum glottal opening and sound pressure level are compared with data found in excised larynges as well as with the values numerically simulated by the aeroelastic model of vocal fold self-oscillations.
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Eating habits of children and youth in selected schools
OHEROVÁ, Martina
Over the last decade, there is an enormous increase in the number of children and young people with health problems due to the non-compliant boarding. This is not only about overweight or obesity, the problem is much broader spectrum - diseases such as diabetes mellitus 2nd type, high blood pressure, high level of cholesterol and other cardiovaskular problems do not affect only adults anymore. This work is focused on primary school pupils and high school students, on finding their eating habits and the following comparison. The work is divided into two parts. The theoretical part includes the basic data describing the quality of eating in the world and in the Czech population and also describes the charakteristics of contemporary boarding. This section also emphasizes the importance of diet for a child´s body in various stages of development, including the intrauterine one. Of course also serves dietary guidelines, both the preferences of specific dietary components and the frequency of meals, distribution of energy intake during the day etc. It also briefly describes the various dietary components and their function in the body, describes the different ways to check the status of human nutrition and the conclusion is devoted to the pathology of child nutrition. The practical part contains the results of research that were gathered through the method of questioning, using questionaires. The data were collected anonymously. Questionnaires were distributed to 7th and 9th classes of primary school and the first and third grades of secondary schools in the district of Jihlava. Respondents answered a total of 15 questions, two of which were open. Of the 65 questionnaires (100%) distributed to elementary school returned 55, 2 of them had to be excluded due to incompleteness, a total of 53 - 82% return. At high school, it was also distributed 65 questionnaires (100%), returned 54 - 83% return. The aim of this study was to determine the dietary habits of children and adolescents, and to assess whether positive approach to healthy nutrition tend to have younger pupils in primary schools, which are still under the powerful influence of parents, or whether the food more cares older high school youth. Based on this goal I set two hypotheses. Hypothesis 1: There are differences in the diet on selected primary and secondary schools in the district of Jihlava. Hypothesis 2: High school youth do not eat in accordance with the food pyramid. After subsequent testing of hypotheses it was proved that differences between primary school pupils and secondary school students actually exist. Surprisingly, the better rating in the test had high school students. Those, besides a consumption of alcohol, have better eating habits - they have regular meals, breakfast was more in line with dietary recommendations, more frequently attend a school canteen, the majority has not been shown to be regularly active smoking etc. At both schools, without distinction, occurred more serious shortcomings in the consumption of fruit and vegetables, there also was a relatively high number of students who have ever tried tobacco and alcohol consumption. In addition to the hypotheses, I also compared the differences in responses depending on gender of respondents and correlation between the resulting score of questionnaire and Body Mass Index which I calculated on the basis of height and weight. Between boys and girls were shown minimal differences, concerning rather morning snacks (girls prefer healthier foods) and more active interest in a healthy lifestyle by girls again. Relationship between Body Mass Index and resulting scores in the questionnaire was not demonstrated. This work may serve to school teachers as a study material in the promotion of a healthy lifestyle, as well as parents of children and adolescents to broaden knowledge of this issue.
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Multilevel Analysis of Continuous Acoustic Emission Records
Chlada, Milan ; Převorovský, Zdeněk
The latest acoustic emission (AE) systems provide continuous recording of high-frequency signals registered during longtime monitoring of various processes in materials. Recorded data represent extremely large amount of information to analyze, however, it reflects the health of the structure. Therefore, in the last years the attention is paid to the diagnostic method of continuous AE also as a part of Structural Health Monitoring (SHM) systems. For example it can disclose the early damage phases (cracks) or certain imperfections in rotating gearboxes, the leakage of liquids from pressure vessels and many other material defects. This method requires new signal processing and analysis approaches, which are different from the burst AE. The paper deals with the analysis of continuous AE, recorded during the test of renovated gearbox at different flight modes. As an alternative to classical spectrogram, so-called multilevel countogram based on the signal wavelet decomposition is proposed and discussed.
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Dynamics of cavitation induced by focused tandem shock waves in water
Hoffer, Petr ; Šunka, Pavel ; Lukeš, Petr
Cavitation associated with the generation of shock waves in water was examined. To study these processes, a tandem shock wave generator, which generates two cylindrical pressure waves focused by a metallic parabolic reflector to a common focal region, was developed. The temporal evolution of cavitation generated by shock waves at the focal region was determined experimentally using high-temporal-resolution microphotography for a certain time delay between the first and second shock waves. Observation of the focal area also showed jetting cavitation bubbles with diameters of 100 m without presence of any rigid boundary. A theoretical model that provides analytical expressions for the temporal evolution of the pressure inside the cavitation bubbles and parameters of the pressure waveform of the second shock wave at the focal area was used to improve the same measurement by PVDF sensor gauges. On the basis of this model, the amplitudes of the compression and rarefaction parts
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