|
|
Properties of faint meteors studied by video observations
Vojáček, Vlastimil ; Borovička, Jiří (advisor) ; Campbell-Brown, Margaret (referee) ; Tóth, Juraj (referee)
Parallel double-station video observations paired with spectroscopic video observations are a good way to study millimetre-sized meteoroids. Almost two decades of video observations of meteors at the Ondřejov observatory give us broad database to study large quantities of meteoroids and their properties. In this work we combined spectral video observations and results of the modelling of the fragmentation of meteoroids. Along with complex infor- mation about meteoroid's trajectories and orbits, this can give us better understanding about origin, internal structure etc. of these millimetre-sized interplanetary bodies. Meteoroids that contained small grains tend to release the sodium early. Since there is a smaller amount of sodium for Na depleted meteoroids, the sodium was released earlier than it was released for meteoroids with same grain sizes and without the sodium depletion. Overall, meteoroids with sodium depletion showed different composition: they were composed of stronger material without very small grains and they did not showed very bright wakes. Two iron meteoroids on Halley type orbits were observed. They are probably remnants of complicated early years of our solar system. The dis- tribution of grain sizes of Jupiter-family members was in a good agreements with results from the COSIMA...
|
|
|
Comparison of three trials used for assassement of ability to disperse by wind and its importance for colonazition of abandoned fields in Asteraceae species
Vlasta, Tomáš ; Knappová, Jana (advisor) ; Kotilínek, Milan (referee)
Several methods are used for studying seed dispersal (seed traps, tracking individual seeds, tracking seeds coloured by fluorescent colours, etc.) However, only a few studies compared results obtained by several methods. In first part of this master thesis, I compared the three above mentioned methods used for studying seed dispersal using species from Asteraceae family. From previous research within the study area (Úštěcko), it is known that dry grassland species are able to colonize abandoned fields. Using seed dispersal data obtained within this theses, I tried to assess the role of seed dispersal on distribution of dry grassland species on abandoned fields both on local and regional scale. The results showed that dispersal curves obtained by the three methods differ significantly. This results may be due to different wind conditions during the experiments. Seed trap data show results from long-term seed dispersal influenced by highly variable wind conditions. In contrary, seed release experiments showed results based on single dispersal event under limited wind conditions. Tracking seeds coloured by fluorescent colours was shown to be not convenient for small seeds, but I can recommend this method for larger seeds. Influence of seed dispersal ability on abundance of dry grassland species on...
|
|
|
Fragmentation of African Political Map: Contemporary Secessionist Movements
Vlasatá, Barbora ; Riegl, Martin (advisor) ; Doboš, Bohumil (referee)
The aim of bachelor's thesis Fragmentation of political map of Africa: current separatist movements is to show secessionist conflicts and movements in Africa that have been active after 2011. In the first part of the thesis there are the explanations of the main terms - separatism, secession, self-determination of nations, separatist and secessionist movements, armed non-state actors and conflicts. In the next part there is an overview of secessionist conflicts that have been active at during at least one year since 2011 and movements that have been part of these conflicts and are the secessionist type of armed non-state actors according to Eran Zohar calling for an independent state. This part also aims to find out if there has been a tendency to internationalization of these conflicts. The last part of thesis is composed of case studies of five african secessionist conflicts and movements - Kata Katanga in Democratic republic of Congo, National Movement for the Liberation of Azawad/Coordination of Movements of Azawad in Mali, Ogaden National Liberation Front and Oromo Liberation Front in Ethiopia and Sudanese People's Liberation Movement/Army-North in Sudan. There is aim to demonstrate the development of these conflicts and also the roots of the conflict, the particular movement and secessionist...
|
|
|
Study of strange particle production in jets with the ALICE experiment at the LHC
Kučera, Vít ; Bielčíková, Jana (advisor) ; Dolejší, Jiří (referee) ; d´Enterria, David (referee)
Title: Study of strange particle production in jets with the ALICE experiment at the LHC Author: Vít Kučera Institute: Institute of Particle and Nuclear Physics Supervisors: RNDr. Jana Bielčíková, Ph.D., Nuclear Physics Institute of the CAS; Dr. Christian Kuhn, Institut Pluridisciplinaire Hubert CURIEN Abstract: Quark-gluon plasma is a state of matter existing under extreme energy densities and temperatures where quarks and gluons are deconfined. Complex phenomena occurring in the plasma emerge from the strong interaction of its constituents. This hot and dense strongly interacting matter can be created in ultra-relativistic heavy-ion collisions and its properties can be studied by measuring particles produced in the collisions. Partons produced in hard scatterings interact with the medium which modifies the production of particles in jets. Measurements of spectra of identified particles produced in jets represent an important tool for understanding the interplay of various hadronization mechanisms which contribute to the particle production in the medium created in heavy-ion collisions. In this thesis, we present the measurement of the pT spectra of Λ baryons and K0 S mesons produced in charged jets in central Pb-Pb collisions at the energy √ sNN = 2.76 TeV, measured in the ALICE experiment at the LHC. The...
|
|
|
Comparison of Time and Memory Categories in Maurice Blanchot's and Pascal Quignards's Essays with the Conception of the Memory in Patrick Modiano's works
Kucherov, Anton ; Šuman, Záviš (advisor) ; Voldřichová - Beránková, Eva (referee)
Anton Kucherov Comparaison des catégories de temps et mémoire dans les essais de Maurice Blanchot et de Pascal Quignard avec la conception de la mémoire dans l'oeuvre romanesque de Patrick Modiano Comparison of Time and Memory Categories in Maurice Blanchot's and Pascal Quignards's Essays with the Conception of the Memory in Patrick Modiano's works _____________________________________________________ This work aims to compare the perception particularities of time and memory categories in the philosophical essays of Maurice Blanchot and Pascal Quignard with the Patrick Modiano's memory of return. This study contains a historical overview of memory and time categories interpretation and examines the particularities of the artistic and subjective memory through the texts of Maurice Blanchot and Pascal Quignard, as well as total novels of Patrick Modiano. This study represents a psychological analysis of memory and its overpersonal, total, fragmental, non-linear and individual process. The realization of this work is ensured by the method of the memory places developed by Pierre Nora, as well as the heuristic method and through phenomenological psychoanalysis. The subject area of memory is important because the concentration of the cultural space needs a treatment of the past. The memory today is a means, an...
|
|
|
Structural analysis of natural compounds with aliphatic branched chains using mass spectrometry
Strmeň, Timotej ; Cvačka, Josef (advisor) ; Kozlík, Petr (referee)
The diploma thesis focuses on analysis of fatty alcohols with mass spectrometry. Theoretical part describes distribution, main properties, usage and analytical methods for analysis of fatty alcohols. Experimental work focuses on the search for a proper derivatisation procedure for fatty alcohols, which would enable their detection with soft ionisation techniques of mass spectrometry, as well as their structural analysis. The main aim of the structural analysis is to find the methyl branching in the fragmentation spectra of derivatives of the fatty alcohols.
|
|
|
Fragmentation of African Political Map: Contemporary Secessionist Movements
Vlasatá, Barbora ; Riegl, Martin (advisor) ; Doboš, Bohumil (referee)
The aim of bachelor's thesis Fragmentation of political map of Africa: current separatist movements is to show african separatist movements which are active at the moment. In the first part of the thesis there are the explanations of the main terms - separatist and secessionist movements, separatism, secession and self-determination of nations. In the next part there is a chart of currently active separatist and secessionist movements and an overview of ongoing conflicts in Africa with emphasis on separatist ones. Next part is concerned with the theory of Jeffery Herbst about connection between emergence and evolution of these movements and conflicts and geographical conditions of african countries. The last part of thesis is composed of case studies of four african separatist movements that are currently active and that led to the outbreak of conflicts in these four countries, of Mai Mai Kata Katanga in Democratic republic of Congo, Sudanese People's Liberation Movement/Army-North in Sudan, Oromia Liberation Front in Ethiopia and Boko Haram in Nigeria. There is aim to show the goals, acts and potential succes of these movements and of the opposing central goverments of these states and to confirm Jeffrey Herbst's theory on these examples.
|
|
|
Fragmentation of African Political Map: Contemporary Secessionist Movements
Vlasatá, Barbora ; Riegl, Martin (advisor) ; Doboš, Bohumil (referee)
The aim of bachelor's thesis Fragmentation of political map of Africa: current separatist movements is to show african separatist movements which are active at the moment. In the first part of the thesis there are the explanations of the main terms - separatist and secessionist movements, separatism, secession and self-determination of nations. In the next part there is a chart of currently active armed separatist and secessionist movements, which are accordant with one of four cathegories of violent non state actors according to Eran Zohar's typology. The last part of thesis is composed of case studies of four african separatist movements that are currently active and that led to the outbreak of conflicts in these four countries, of Mai Mai Kata Katanga in Democratic republic of Congo, Sudanese People's Liberation Movement/Army-North in Sudan, Oromia Liberation Front in Ethiopia and Boko Haram in Nigeria. There is aim to show the goals, number of soldiers or members, or international domestic support of the movements and also if activities of these movement have led to an armed conflict. The thesis also aims to verify, if the theory of Pavkovic and Radan about emergence of separatist movements, is in accordance with contemporary african movements.
|
|
|
Fragmentation and homogenization of forest communities in urban areas
Pevná, Tereza ; Vojta, Jaroslav (advisor) ; Prach, Jindřich (referee)
This bachelor thesis deals with issue of fragmentation and homogenization of forest communities in urban areas. The habitat fragmentation could be natural or anthropogenic. The main cause of the habitat fragmentation is currently human activity. We can count urbanization among the most significant of these activities. The extinction is one of the few effects, which is however very significant for the biodiversity of the fragmented habitat. The extinction of species in the fragmented habitat does not necessarily occur immediately. In the fragmented habitat, a decrease in the number of species can take place with some delay. There is another fact connected to the extinction in the fragmented habitat. The biotic homogenization can also occur in the fragmented habitat. The biotic homogenization is distinctive and easily observable particularly in urbanized area. Powered by TCPDF (www.tcpdf.org)
|
|
|
Methods for studying seed dispersal and its importance for colonization of new sites
Vlasta, Tomáš ; Knappová, Jana (advisor) ; Hemrová, Lucie (referee)
Study of seed dispersal is crucial for understanding of several processes in life of plants and landscape. Seed dispesal is very important for persistence of local populations in fragmented landscape, it plays an important role in succession, it helps to protect plant populations againts loss of genetic variability. We usually recognize several types of seed dispersal depending on vector (dispersal by wind, animals and water.) In nature, it is very common that seed can be independently dispersed by several vectors. Therefore, studying of polychory and secondary dispersal is necessery. Methods of studying of seed dispersal are very variable, including seed traps, releasing and following individual seeds, genetics marcers etc. If we study seed dispersal, we should select the most suitable method depending on the aim of the study. We should also take into acount advantages and disadvantages of single method.
|
guest ::
