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A method for the solution of non-spherical (fiber) particles deposition by means of the Fokker-Planck equation for ODF in a laminar flow
Kopečková, Barbora ; Knotek, Stanislav (referee) ; Jícha, Miroslav (advisor)
The Bachelor's thesis deals with a deposition efficiency for a fibers by various mechanisms of a deposition. It explains deposition efficiency by diffusion, by sedimentation and by impaction. The implementation of Peterlin's analytical solution for calculation of the ODF, which is used for individual efficiencies solution, is also mentioned. Afterwards, the thesis summarizes formulas for calculation of particular efficiencies derived for spherical particles and recomputation appropriate parameters for fibers. The purpose of the thesis is to create graphs, which illustrate deposition efficiencies dependence by various mechanisms on the aspect ratio of fibers. Another goal is the graphs creation, which shows juxtaposition for various breathing modes for given deposition mechanisms. The software MATLAB is used for the whole calculation process and graphs plotting.
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Exploration of extraterrestrial body impact and UV-driven transformation of atmospheres of terrestrial planets
Knížek, Antonín ; Ferus, Martin (advisor) ; Kabáth, Petr (referee) ; Kopecký, Vladimír (referee)
Keywords: Exoplanets, Earth, Impact, Photochemistry, Infrared Spectroscopy, Atmospheric chemistry Impacts and photochemistry are two very important driving forces for chemical transformation of planetary atmospheres. While strong UV radiation produced by young stars continuously provides a significant amount of energy, impacts are one-time events with far-reaching consequences. Especially important are then impacts on young rocky planets, including the early Earth, because these planets are likely exposed to much higher impact fluxes, commonly called 'heavy bombardment'. This bombardment is the final echo of the turbulent planetary accretion and has prominent significance for planetary environments, e.g., the chemical composition and shape of the planetary surface, the chemistry of atmospheres, aerosol production, and likely the origin of life. Future observations of exoplanets by space telescopes, such as the James Webb Space Telescope or Ariel, as well as ground-based telescopes, such as the Extremely Large Telescope currently under construction in Chile, could determine whether this heavy bombardment represents a common scenario for the evolution of terrestrial planets. Both impacts and photochemistry can be efficiently simulated and studied in laboratory conditions by state-of-the-art methods....
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Dynamic load during reactive strength tasks
Kováč, Dan ; Hojka, Vladimír (advisor) ; Vindušková, Jitka (referee)
Title: Dynamic load during reactive strength tasks Objectives: Objectives were to explore and measure biomechanic parameters of athletes performing different reactive strength tasks using force plates. Methods: 8 male athletes (22,4 ± 1,2 years; 76,3 ± 4,3 kg) took part in experiment. Each of them performed 8 different reactive strength tasks (alternate and single leg bounds, pogo jumps on place, low hurdle jumps, high hurdle jumps 76 cm and 91 cm and long jump take off from 8 and 12 steps approach). Dynamics of tasks was measured using Kistler 9281 EA with sample rate of 1000 Hz. Main observed parameters were maximum vertical force, time to peak force, contact time and impulse. Data were processed in MATLAB R2022a (The MathWorks, Inc. Natick, Massachusetts, USA) and Microsoft Excel 2019. Results: Differences in dynamics of reactive tasks were observed among single leg and double leg exercises. Double leg exercises had much longer time to peak of vertical force than single leg exercises. Biggest vertical forces were observed during single leg bounds, where overload reached seven times body weight. On the other hand lowest peak of vertical force was measured during long jump takeoff from eight steps approach. Maximal forces got higher and contact time shorter with increased approach speed during...
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Study of ecosystem impact of giant hogweed (Heracleum mantegazzianum) invasion
Hladík, Marek ; Pergl, Jan (advisor) ; Hadincová, Věroslava (referee)
The present study deals with ecological impact of giant hogweed (Heracleum mantegazzianum) invasion in Slavkovský les area. Being one of the prominent invasive species with significant impact on human health it has been subjected to a wide research. In spite of that little is known about its impact on the invaded ecosystem. My research was therefore focused on analysis of the ecosystem impact, particulary 1) microclimatic measurements of temperature and soil moisture and their comparisons between invaded and noninvaded vegetation, 2) comparison of germination and survival of model plant species sowed into invaded and noninvaded plots and 3) study of the effect of H. mantegazzianum presence on model species seed production. Results have shown significant alteration of microclimate due to H. mantegazzianum invasion. Further research is needed to resolve what impact it may pose to species in invaded communities. The effect of Heracleum mantegazzianum presence on germination and survival of model species was not significant. Similarly, seed production of model plants was not significantly affected.
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Modeling of meteorite impact
Takáč, Marian ; Kletetschka, Günther (advisor) ; Kohout, Tomáš (referee)
In Febuary 2013, in spectacular light and sound accompaintmen a meteorite hit the Russian Federation. Small fragment which landed in populated areas caused together with blust wave damage. The largest part broke the ice crust on the lake in outskirts of Chebarkul. The circular shaped hole gave rise to various conspiracy theories. About half of the year after impact the meteorite was lifted and conspiracy theories boken. The event immediately raised interest in the issue of the impacts of meteorites and phenomena associated with them. Processes when the meteor is passing trough atmosphere, impact craters, their origin and characteristics, computer models, types of meteorites and their origin. Or just a mystery of the hole in the ice crust of the lake Chebarkul. Science has got answers for such toppics. This paper is just trying to summarize them.
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Impacts of invasive plant species on European environment
Breburdová, Vendula ; Pyšek, Petr (advisor) ; Kindlmann, Pavel (referee)
The DAISIE project in the 6. framework program of the European Union provides valuable data about European invasive species. Invasive plants have various impacts, positive and negative, and effects all four types of ecosystem services (supporting, provisioning, regulating and cultural). Invasive species are also known to cause serious economic looses. The proposed work aims at summarizing the up-to-date knowledge about the impact of invasive flora on European environment and human well-being. key words: invasive plants, impact, DAISIE, Europe, ecosystem services
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Modeling of meteorite impact
Takáč, Marian ; Kletetschka, Günther (advisor) ; Kohout, Tomáš (referee)
In Febuary 2013, in spectacular light and sound accompaintmen a meteorite hit the Russian Federation. Small fragment which landed in populated areas caused together with blust wave damage. The largest part broke the ice crust on the lake in outskirts of Chebarkul. The circular shaped hole gave rise to various conspiracy theories. About half of the year after impact the meteorite was lifted and conspiracy theories boken. The event immediately raised interest in the issue of the impacts of meteorites and phenomena associated with them. Processes when the meteor is passing trough atmosphere, impact craters, their origin and characteristics, computer models, types of meteorites and their origin. Or just a mystery of the hole in the ice crust of the lake Chebarkul. Science has got answers for such toppics. This paper is just trying to summarize them.
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Impacts of invasive plant species on European environment
Breburdová, Vendula ; Pyšek, Petr (advisor) ; Kindlmann, Pavel (referee)
The DAISIE project in the 6. framework program of the European Union provides valuable data about European invasive species. Invasive plants have various impacts, positive and negative, and effects all four types of ecosystem services (supporting, provisioning, regulating and cultural). Invasive species are also known to cause serious economic looses. The proposed work aims at summarizing the up-to-date knowledge about the impact of invasive flora on European environment and human well-being. key words: invasive plants, impact, DAISIE, Europe, ecosystem services
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Study of ecosystem impact of giant hogweed (Heracleum mantegazzianum) invasion
Hladík, Marek ; Pergl, Jan (advisor) ; Hadincová, Věroslava (referee)
The present study deals with ecological impact of giant hogweed (Heracleum mantegazzianum) invasion in Slavkovský les area. Being one of the prominent invasive species with significant impact on human health it has been subjected to a wide research. In spite of that little is known about its impact on the invaded ecosystem. My research was therefore focused on analysis of the ecosystem impact, particulary 1) microclimatic measurements of temperature and soil moisture and their comparisons between invaded and noninvaded vegetation, 2) comparison of germination and survival of model plant species sowed into invaded and noninvaded plots and 3) study of the effect of H. mantegazzianum presence on model species seed production. Results have shown significant alteration of microclimate due to H. mantegazzianum invasion. Further research is needed to resolve what impact it may pose to species in invaded communities. The effect of Heracleum mantegazzianum presence on germination and survival of model species was not significant. Similarly, seed production of model plants was not significantly affected.
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A method for the solution of non-spherical (fiber) particles deposition by means of the Fokker-Planck equation for ODF in a laminar flow
Kopečková, Barbora ; Knotek, Stanislav (referee) ; Jícha, Miroslav (advisor)
The Bachelor's thesis deals with a deposition efficiency for a fibers by various mechanisms of a deposition. It explains deposition efficiency by diffusion, by sedimentation and by impaction. The implementation of Peterlin's analytical solution for calculation of the ODF, which is used for individual efficiencies solution, is also mentioned. Afterwards, the thesis summarizes formulas for calculation of particular efficiencies derived for spherical particles and recomputation appropriate parameters for fibers. The purpose of the thesis is to create graphs, which illustrate deposition efficiencies dependence by various mechanisms on the aspect ratio of fibers. Another goal is the graphs creation, which shows juxtaposition for various breathing modes for given deposition mechanisms. The software MATLAB is used for the whole calculation process and graphs plotting.
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