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Změny využití krajiny v okolí jaderné elektrárny Černobyl
Libánková, Ivana
The work deals with the mapping of the land-use changes in the area of the Nuclear Power Plant Chernobyl. There is a comparison how was earth used before an accident of the Nuclear Power Plant Chernobyl and now. The thesis includes some interviews with people who live in the mapped area-old local residents, workers from the forestry station of Paryshiv area. The mapped area had to contain forest land, agricultural land, and watercourse. I used the mapping methods by Vondrušková (1994). In this work I suggest measures to the maintaining zone and the functioning zone. The result of the work is the map with mapped elements and the text file with the detailed description of the elements and area.
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Index listovej plochy a priestorová distribúcia asimilačného aparátu v poraste buku lesného (Fagus sylvatica L.)
Haninec, Pavel
One of the most important parameters determining penetration of the photosynthetically active radiation (FAR) through the forest canopy is the leaf area index (LAI). In this thesis we concerned with a comparison of direct and indirect approaches of determining LAI and the vertical distribution of LAI in the canopy. There have been used three optical methods, using the device LiCor LAI 2200 Plant Canopy Analyzer, LaiPen and hemispherical photography. Also, we used the method of estimation LAI using airborne laser scanning. There was created allometric relationship between leaf area and the perimeter of the sample trees. These trees were also destructively processed and based on those, there were created the diagrams of the vertical distribution of leaves in the crowns of these trees. The individual values of the measured leaf area index, were in amplitude from 3.69 m2.m-2 to 11.80 m2.m-2 and the indirect methods underestimated the direct approach in average of 28.46%.
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Bird diversity and diversification: Different processes converging to the same pattern?
Černá, Vladimíra ; Storch, David (advisor) ; Hulva, Pavel (referee)
Latitudinal diversity gradient is one of the oldest known trends in the distribution of life on the Earth. Scientists have been trying to find causes of its formation for more than two hundred years. There are several hypotheses suggested to explain this gradient. Recently, it is one of the main themes of discussion among ecologists and evolutionary biologists. By this Thesis, I will try to contribute to understanding of processes that generate the latitudinal diversity gradient. Particularly, I study if there is a relationship between ambient temperature and diversification rate. Is this relationship different for individual groups of animals? I choose birds as a model group. Specifically, these six families of birds: Accipitridae, Columbidae, Furnariidae, Picidae, Psittacidae and Strigidae. These groups include more than 1500 species. Each of them has the same universal gradient of diversity, with the highest diversity concentrated in the tropics. My objective was to find out, whether the universal gradients of bird's diversity had been shaped by the same historical processes. Or alternatively, whether different evolutionary trajectories had converged to the same gradients. The main outcome of my work is a discovery that some of the selected families diversified faster in warmer climates...
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Control unit for CubeSat
Horký, Jan ; Šulc, Tomáš (referee) ; Kubíček, Michal (advisor)
Cílem práce je návrh univerzální řídicí jednotky pro CubeSat založené na obvodu FPGA. Taková jednotka doposud nebyla komerčně dostupná a navržená jednotka má tak dobrý potenciál zaplnit příslušné místo na trhu komponent pro CubeSat. Celá jednotka je navržena z komerčně dostupných komponent. Návrh jednotky je proveden tak, aby umožnil její funkci ve vesmírném prostředí. Stav konfigurace FPGA je pravidelně kontrolován a v případě zjištěné chyby dochází automaticky k rekonfiguraci FPGA a návratu jednotky do výchozího stavu. Jednotka obsahuje sadu senzorů, které monitorují její stav a v případě potřeby je možné na základě jejich výstupů provést opatření z hlediska ochrany funkce jednotky. Dvě paměti MRAM umožňují uložení tovární a uživatelské konfigurace FPGA, mezi kterými dochází k automatickému přepnutí na základě korektnosti uživatelské konfigurace.
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The factors affecting evolutionary diversification
Černá, Vladimíra ; Storch, David (advisor) ; Kratochvíl, Lukáš (referee)
The number of species on the Earth is estimated to lie between five to ten millions. All these species originated from a common ancestor, which appeared on our planet 3,5 bilion years ago. Speciation and extinction are responsible for the current species richness. Evolutionary diversification is the difference between speciation and extinction. There are several methods used to obtain the values of speciation, extinction and diversification rates. I will briefly explain some of these methods, outline the advantages and disadvantages of them. The aim of this paper is to summarize current knowledge of evolutionary diversification and factors that may affect it. In this search I focused on the studies dealing with factors that may affect several groups of organisms. Although many determinants of diversification were found, most of them affect only one group of organisms. Here I did not find any factor that would be common for the majority of taxa. Evolutionary diversification is probably influenced by different factors in different evolutionary lineages. Key words: diversification, speciation, radiation, diversity gradient
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Assessment of the average radiation exposure from medical diagnostics
BALTA, Petr
The diploma thesis dealt with the theme of "Assessment of the average radiation exposure from medical diagnostics" is divided into two main parts. The first one is concerned with the various measurement of radiation dose during diagnostic medical radiation. The second one is focused on radiation dose optimization during diagnostic medical radiation. With increasing of the collective effective dose in population, we should consider the importance of radiation protection during diagnostic medical radiation and accuracy of effective dose estimate that is used during individual medical examinations. On the basis of these estimates, it is necessary to determine the medical theory of radiation protection and to gain control over radiation dose and optimization of diagnostic medical radiation somehow. The theoretical part describes the kinds of ionizing radiation and their biological effects on organism. This part follows the chapter devoted to radiation protection and legal framework of the Czech Republic that is related to the topic: the application of ionizing radiation, mainly the Act No. 18 /1997 Coll. on Peaceful Utilisation of Nuclear Energy and Decree of the SÚJB No. 307 /2002 Coll., on Radiation Protection. There are discussed also the particular principles of protection against radiation. Afterwards, in the theoretical part, the quantities and the units used by radiodiagnostics and nuclear medicine are described. They are needed to know for the following determination and the estimate of dose amount absorbed by human organism. The conclusion of the theoretical part treats the methods used for estimate of dose received during medical examination and new trends in radiation management of individual patients. In the diploma thesis, there are set up two research questions. The thesis has been looking for the answers by its own research. The first research question is, if the current way of measurement of radiation dose is sufficient. The second one has been asking for manners of access allowed the decreasing of dose for patients regarding to registered effective dose. On the basis of these defined research questions, the basic aims have been set up to consider the application of individual methods of dose evaluation during medical radiation, to determine, from the registered values, probably the most exact method for evaluation of radiation dose and to deduce the probability of stochastic effects formation conditioned by radiation. The research was performed with two groups of patients that were undergone skiagraphic examination of lungs and examination of stomach by computed tomography (CT). The research devoted to skiagraphic examination of lungs was dealt with women suffering by similar body constitution. The results of measured effective dose of these patients were compared, and the manner of measurement and influencing of final absorb dose in the mammary gland were presented. The relation of individual projections towards probability of cancer birth conditioned by radiation was demonstrated. For comparison and setting up the most exact method, the first group was measured by the most available and the most common way used in clinical practice. PCXMC and ImPACT CT software are the most applying methods in clinical practice. As the most available method, standardize values and the procedure from the Bulletin of the Ministry of Health for Radiation Physics were applied. The final effective doses were compared with the local and national diagnostic referential levels in order to set up the correct procedure of radiation protection. The second researched group of patients undergone stomach examination performed by computed tomography (CT). The final effective doses of these patients were compared according to ICRP 60 and ICRP 103. Just as in the first group, there were compared two methods of measurement, the most available and the most applying in the practice.
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Gamma Radiation Measurement
Lázna, Tomáš ; Jílek, Tomáš (referee) ; Žalud, Luděk (advisor)
This thesis is focused on detection of ionizing radiation, especially gamma radiation. In its theoretical part the issue is presented and the most common detector types (gas filled, scintillation and semiconductor detectors) are analysed. In its practical part the parameters of the chosen sensor HDS-100GN are verified with a focus on its capability of dynamical measurement. The robot Orpheus-X3 equipped with the precise RTK-GNSS receiver was used in the realization of the experiment. The analysis of the measurement results furthermore covers conversion of geographical coordinates to distance, determination of latency, conversion of measured value to dose rate and comparison with theoretical assumptions were solved. Formation of an area radiation map is also concerned. Direction-sensitive detection of gamma radiation is also studied in this thesis.
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Computational Modeling of Turbulent Swirling Diffusion Flames
Vondál, Jiří ; Klemeš,, Jiří (referee) ; Tuček,, Antonín (referee) ; Hájek, Jiří (advisor)
Schopnost predikovat tepelné toky do stěn v oblasti spalování, konstrukce pecí a procesního průmyslu je velmi důležitá pro návrh těchto zařízení. Je to často klíčový požadavek pro pevnostní výpočty. Cílem této práce je proto získat kvalitní naměřená data na experimentálním zařízení a využít je pro validaci standardně využívaných modelů počítačového modelování turbulentního vířivého difúzního spalování zemního plynu. Experimentální měření bylo provedeno na vodou chlazené spalovací komoře průmyslových parametrů. Byly provedeny měření se pro dva výkony hořáku – 745 kW a 1120 kW. Z měření byla vyhodnocena data a odvozeno nastavení okrajových podmínek pro počítačovou simulaci. Některé okrajové podmínky bylo nutné získat prostřednictvím dalšího měření, nebo separátní počítačové simulace tak jako například pro emisivitu, a nebo teplotu stěny. Práce zahrnuje několik vlastnoručně vytvořených počítačových programů pro zpracování dat. Velmi dobrých výsledků bylo dosaženo při predikci tepelných toků pro nižší výkon hořáku, kde odchylky od naměřených hodnot nepřesáhly 0.2 % pro celkové odvedené teplo a 16 % pro lokální tepelný tok stěnou komory. Vyšší tepelný výkon však přinesl snížení přesnosti těchto predikcí z důvodů chybně určené turbulence. Proto se v závěru práce zaměřuje na predikce vířivého proudění za vířičem a identifikuje několik problematických míst v použitých modelech využívaných i v komerčních aplikacích.
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Heat exchanger for rescue habitat
Bouma, Adam ; Kilkovský, Bohuslav (referee) ; Jegla, Zdeněk (advisor)
This thesis deals with the specific issues of designing a suitable type of heat exchanger for ventilation in a rescue habitat. The paper presents an overview of the most common types of heat exchangers and characterizes basic heat transfer mechanisms (radiation, convection). Based on the above and other knowledge, a thermal-hydraulic calculation model suitable for a regenerative heat exchanger type is compiled and the necessary calculations are performed. The thesis also contains an evaluation of the results for three materials which can be used in the production of a heat exchanger (aluminum, copper, steel).
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Verification of thermal-insulation properties of the foil materials
Šot, Petr ; TROJAN,, Karel (referee) ; Šťastník, Stanislav (advisor)
The master´s thesis deals with verification of thermal insulating property of thermoreflection foil insulations. The teoretical part of thesis focuses on the energy demand of buildings, the problems of heat transfer material, terms required for study of thermoreflection thermal insulation and experimental methods for determination of thermal insulating properties of insulators. In the next part the chapter is accompanied by an overview of the most common insulation materials which used in construction. The last part of teoretical part is devoted to the description of thermoreflect formation and analysis of the spread of thermal insulating layers of thermoreflection thermal insulation. The first part of thesis is devoted to the use of thermoreflection therm insulation in buildings. The second part of thesis is devoted to the design, assembly and calibration of the measuring device that uses a method of protected warm chamber. It is declared as a binding method of detection of the heat transfer performance of thermoreflection thermal insulation. The developed measuring device allows detection of endpoints in some direction of propagation of heat. Measurment of heat transfer coefficient devoted the third part of practical part. This part contains a description of the samples used for the measurement of the heat transfer coefficient. In the fourth chapter of the practical part are presented the results of the heat transfer coefficient measurments on selected samples of thermoreflection foil insulation. It is shown the characteristic of heat transfer coefficient of individual samples, the dependence of the heat transfer coefficient on the position of the sample in the measuring device and the recommendation of an appropriate use of sample in the works for the climatic conditions of the Czech republic. The work concludes the chapter of comparing and evaluating of all samples with practical recommendations.
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