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Geobiocenózy přírodní rezervace Bayerova po 35 letech - srovnávací studie
Žalmanová, Kateřina
The aim of this work is to evaluate the vegetation changes that have taken place in Bayerova Nature Reserve over the last 35 years. 14 phytosociological plots and 2 transects were renewed for this purpose. These were originally established by Koutecký in 1982. Data were collected according to the original methodology. Vegetation changes have been determined based on the principal component analysis (PCA) and fidelity rates. European beech has expanded to the detriment of other trees, especially Norway spruce and Sessile oak. Individuals of these species died as a result of their deteriorating conditions. Additionally, there was no evidence of their regeneration. Most plots are now moister and more nutritious. As a result, more nutrient-demanding species appeared in the plots. Number of light-demanding and heat-tolerant species has decreased. The results also showed homogenization. A similar trend is observed in other Central European countries
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News in the field of the road construction
Zelenka, Lukáš ; Zajíček, Jan (referee) ; Varaus, Michal (advisor)
The bachelor’s thesis focuses on new technological equipment for transport and paving of asphalt mixtures. Specifically, it is a thermo superstructure with an extrusion face and a homogenization tank of an asphalt mixture. The advantages of these machines and their positive influence on the quality of the work are described. Subsequently, the researches which confirm it are described. The last chapter describes recommendations for the contracting authority to require the use of these technologies in tenders.
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Homogenization of flows of non-Newtonian fluids and strongly nonlinear elliptic systems
Kalousek, Martin ; Kaplický, Petr (advisor)
The theory of homogenization allows to find for a given system of partial differential equations governing a model with a very complicated internal struc- ture a system governing a model without this structure, whose solution is in a certain sense an approximation of the solution of the original problem. In this thesis, methods of the theory of homogenization are applied to three sys- tems of partial differential equations. The first one governs a flow of a class of non-Newtonian fluid through a porous medium. The second system is utilized for modeling of a flow of a fluid through an electric field wherein the viscosity depends significantly on the intensity of the electric field. For the third system is considered an elliptic operator having growth and coercivity indicated by a general anisotropic inhomogeneous N-function. 1
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CFD modelling of pipe flow mixing of liquids
Pavlíček, David ; Hájek, Jiří (referee) ; Juřena, Tomáš (advisor)
This work is focused on computational modelling of mixing fluids in pipeline with static mixers. Main objective is to analyze several selected static mixers in a particular industrial application, namely dosing of the aluminium sulphate solution in the clarification process for potable water treatment. The analysis focuses on the degree of mixedness and pressure loss of individual mixers. Further, the aim of this work is to process the search of available types of static mixers. The benefit of this work is at least an effort to motivate the reader to deeper understanding of the mixing fluids, especially by static mixers.
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Design of the composite rotor sleeve of a high speed rotary machine
Pavlík, Ondřej ; Ševeček, Oldřich (referee) ; Návrat, Tomáš (advisor)
The diploma thesis focuses on manufacturing carbon fiber and epoxy composite material using filament winding method. Material properties of manufactured composite are ap-proximated using analytical and numerical homogenization models. Calculated material properties are applied to design and evaluate reserve factor of retaining sleeve for high speed brushless permanent magnet synchronous motor. Margin of safety of designed rotor is evaluated using composite failure criteria. Test stand for both static and dynamic testing is designed, static test stand is manufactured and assembled. Static strength test is carried out.
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Sample preparation for DNA analysis from foods of plant origin
Silná, Renata ; Rittich, Bohuslav (referee) ; Kovařík, Aleš (advisor)
The isolation of high quality DNA is nessecary for many molecular biology applications. However, plant DNA contains high amonts of polysaccharides, polyphenols and various secondary metabolites, which decrease yield and quality of isolated DNA. The aim of this study was preparation of samples and different food matrices for DNA isolation DNA by magnetic particles. It was about 5 species of vegetable and 10 species of processed plant food. Homogenization of samples was performed in CTAB buffer. Isolation of plant DNA was performed by magnetic particles covered with carboxyl groups. All DNAs were isolated in conventional PCR qualities using primers for 700 bp amplicons, in the case of heat processed products for 220 bp ampilicons and for real time PCR. The efficiancy of separation of magnetic particles with DNA by magnetic separator and magnetic needle was compared. It was find out that DNA of higher purity was isolated using magnetic needle. The micromethod of isolation of plant DNA from homogenates with CTAB with magnetic particles is suitable for different processed food.
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Mollusca of European cities
Wolfová, Lucie ; Juřičková, Lucie (advisor) ; Drvotová, Magda (referee)
This bachelor thesis summarises knowledge of urban mollusc fauna. It shows cities as the centres of mollusc diversity in agricultural landscape but also as areas where high level of homogenization of mollusc assemblages were evidenced, therefore replacing native species, often endemics, with non-native and invasive species. Homogenization of urban mollusc fauna is especially caused by passive dispersal of species by human as well as to urban climate that is more favourable for spreading and surviving of non-native species, usually from warmer areas, than surrounding. There is mentioned another connected topic in this thesis - types of mollusc spreading. Furthermore, there is summarized which species of mollusc are typical for urban environment, what are the factors influencing the mollusc fauna and last but not least the methodological approaches for study of urban mollusc fauna.
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Homogenization of flows of non-Newtonian fluids and strongly nonlinear elliptic systems
Kalousek, Martin ; Kaplický, Petr (advisor) ; Diening, Lars (referee) ; Schwarzacher, Sebastian (referee)
The theory of homogenization allows to find for a given system of partial differential equations governing a model with a very complicated internal struc- ture a system governing a model without this structure, whose solution is in a certain sense an approximation of the solution of the original problem. In this thesis, methods of the theory of homogenization are applied to three sys- tems of partial differential equations. The first one governs a flow of a class of non-Newtonian fluid through a porous medium. The second system is utilized for modeling of a flow of a fluid through an electric field wherein the viscosity depends significantly on the intensity of the electric field. For the third system is considered an elliptic operator having growth and coercivity indicated by a general anisotropic inhomogeneous N-function. 1
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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)
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Forest vegetation in Eastern Elbe Basin in the mid-20th century and today
Pospíšková, Marie ; Hédl, Radim (advisor) ; Novák, Jan (referee)
This thesis describes the shift in vegetation of broadleaf forests in eastern part of the Elbe River Basin between 1958-1968 and 2011-2013. It emphasizes the understorey vegetation. From lowland woodlands in other temperate regions in Europe and North America changes towards eutrophic and mesophytic vegetation are documented, specifically driven by changes in forest management and by atmospheric depositions; in some localities the game impact can be also important. The data were obtained by sampling 190 typological semi-permanent plots, which were precisely located - in 43% the original soil pit was found. The vegetation on study sites shifted towards nutrient-demanding, shade- adapted species, it was partly ruderalized. These changes can be seen on the level of species and communities as well as on phytosociological level. Increase of soil pH and moisture was discovered using Ellenberg indicator values. The number of seedlings and cover of shrubs also increased significantly. Homogenization of sites was significant as well although total number of species and alpha- diversity remained unchanged. These changes are probably caused by changes in forest management and by atmospheric depositions of nitrogen. On subset of plots in game-preserves the vegetation also demonstrated eutrophication but no increase in...
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