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Leaf physiological and optical properties in relation to the Phytophtora × alni infection of black alder (Alnus glutinosa)
Oramová, Viktorie ; Lhotáková, Zuzana (advisor) ; Tomášková, Ivana (referee)
A current problem is the infestation of the black alder (Alnus glutinosa) by the pathogen P. × alni, which causes the loss of alder stands and disrupts riparian ecosystems. The spread of the 'phytophthora disease' occurs through water, the host is infected through the root system and the pathogen attacks the conductive tissues. As a result of the disease, the tree gradually loses its root system, lesions appear on the trunk, defoliation occurs and the individual inevitably dies. The only solution to the situation is preventive measures to prevent further spread by careful removal of infected alder trees. The aim of this paper is to discuss the relationship between black alder and P. × alni in the context of the physiological changes that occur in the foliage of the infested individual. Leaf functional traits, chlorophyll fluorescence and optical properties of black alder exposed to P. × alni (inoculation into soil or confirmed occurrence of the pathogen in natural conditions) were measured using non-invasive methods. The results of the chamber experiments suggest that the mean values of the measured parameters do not change significantly in the initial stages of infection, but there is a widening of the variance of the values in infected individuals. We tested whether the genetic origin of the...
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Seasonal dynamics of physiological parameters of Norway spruce needles in mountain forest in relation to water balance of the forest site
Bednář, Pavel ; Albrechtová, Jana (advisor) ; Gebauer, Roman (referee)
Norway spruce (Picea abies (L.) Karst.) is an important economic tree species in the Czech Republic, which is currently significantly weakened and dying under the impacts of climate change. In young spruce forest stand in mountain region that was artificially established after the large-scale disturbance of forests in the mid-1990s, on the "U Dvou louček" research plot represented by a small forest catchment of an area of 32.6 ha, located in the upper part of the Orlické Mountains at an altitude of 880 - 920 m a.s.l., and in site conditions of predominantly Abieti-fageta piceae - water balance measurements were carried out during the 2019 and 2020 growing seasons. At the same time, during the mentioned two years, in total 6 samplings of biological material were carried out according to a standardized sampling methodology, and laboratory analyzes were carried out on this material. Laboratory analyzes were focused on three established age categories of needles, namely 1, 2, and 4 or more years old. The biophysical parameters of needles were determined based on the measurement of structural parameters and concentrations of photosynthetic pigments - chlorophyll a, chlorophyll b and total carotenoids from samples extracted in DMF using a laboratory spectrophotometer. Optical properties of the needles...
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Physiological status of young silver fir on stands with different microclimate using biochemical, and optical needle traits.
Kabilková, Eva ; Lhotáková, Zuzana (advisor) ; Pokorný, Radek (referee)
Silver fir (Abies alba Mill.) is a candidate tree species in the process of forest transformation especially of spruce monoculture stands (Picea Abies (L.) H. Karst.), thanks to its better growth characteristics in conditions of mild drought. However, fir, as a very shade tolerant tree, may be more susceptible to various abiotic stressors in more open forest canopies, and therefore it is necessary to study its ecological requirements in connection with the most effective possible application in forestry. In this thesis, the physiological state of young fir stands affected by different light microclimatic conditions, which were represented by different types of forest regeneration, was studied. Specifically, it is shelter-wood cut, which represents the likely highest degree of shading by mature trees, then natural regeneration under sparse canopy, gap cut and small clear cut, which represent a moderate degree of shading by mature trees, and last but not least, clear cut, which represents the lowest degree of shading. Physiological status was evaluated using biochemical and optical properties of the needles, and additional microclimatic conditions of the habitats, namely temperature and soil moisture, were also evaluated. Our results showed that the used biochemical and optical properties of the...
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Study of the thermal insulation effect of thermally reflective insulations
Skříček, Darek ; Vala, Jiří (referee) ; Čermák, Jan (referee) ; Šťastník, Stanislav (advisor)
The dissertation on the topic Study of the thermal insulation effect of thermally reflective insulations is focused on the issue of measuring the thermal resistance R of thermoreflective insulations and determining the most suitable layer with the best thermal insulation properties. By measuring thermoreflective insulations on the Hot-Box measuring chamber, it was proven that higher values of thermal resistance R are always achieved with aluminum foil, which has the highest possible reflection of the radiant component of heat, i.e. the lowest possible emissivity on the surface. For this reason, the reflectance was measured on the Mid-IR Integrat IR ™ measuring apparatus. To study the thermal insulation effect of thermoreflective insulations, ten samples of these insulations with different compositions of aluminum and bubble foils are used to measure the insulation properties. The suitability of using thermoreflective insulation for building insulation was proven by measuring these foils.
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Study of utility properties thermal-reflective insulations in the buildings
Holeček, Dominik ; Skříček, Darek (referee) ; Šťastník, Stanislav (advisor)
The diploma thesis is partly dedicated to energetic efficiency of buildings and describes possibilities how to evaluate energetic efficiency of buildings in the Czech Republic. We also get to know with distribution of thermal insulators by material base and use in construction. There are also mentioned methods how to determine thermal insulations characteristics of heat insulations, so called heat conductivity coefficient. The last and the crucial chapter of theoretic part is dedicated to thermal-reflective insulations. There are mentioned some of the basic characteristics of insulations, material composition and heat transfer mechanism in their structure as well. Practical part describes measurement of thermal resistance of chosen samples of thermal-reflective insulations per measuring device on the principal of Hot Box method. In the next step was determined emissivity of aluminium foils which forms the surface of chosen samples of thermal-reflective insulations. In the end of thesis are defined possibilities of use thermal-reflective insulations in building structures especially in passive and low-energy buildings in climatic conditions of the Czech Republic.
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Testing of room acoustics
Toufarová, Tereza ; Špalek, Karel (referee) ; Sigmund, Milan (advisor)
This paper presents parameters of evaluation of acoustic quality of the space. It is divided into parts presenting physical principle of the origin and movement of the acoustic signal, principles of its processing with current technology and properties of the acoustic field. This is followed by an analysis of the musical part and notes on psychoacoustics. The document contains a description of relevant parameters of acoustic spaces and way in which we can reach desired results, including material analysis. The paper mainly focuses on description of relevant parameters of three acoustic spaces which were measured. The last part of the work is a program for elementary acoustical measurement, which can be provided by means of commonly accessible equipment such as a notebook or a personal computer.
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Non-invasive Blood Glucose Measuring
Vítová, Hana ; Chmelař, Milan (referee) ; Sekora, Jiří (advisor)
Goal of my master´s thesis is examination of non-invasive blood glucose measurement methods, and designing of device for non-invasive blood glucose reading. The introductory chapter of thesis contains description of know different methods for blood glucose measurement, mainly Near Infra-Red region (NIR) measurement with spectroscopy methods. This project describes pathology of Diabetes Mellitus, specifies how it is divided, and looks also on human metabolism. The theoretical part contains exploration of blood glucose measurement methods. Thesis continues with system scheme design for non/invasive glucose measurement device, based on present knowledge. Major principle of device is measuring with Infra-Red laser, bifurcate optic fiber and photodiode. Design of printed circuit board is also present. Document contains also designs of software diagrams for calibration and processing program written in C# language. Communication between device and computer is made via USB. Microcontroller with C language program is part of designed device. It is used to send measured values into PC and also receives data from computer. This data determines blood glucose concentration and their thresholds.
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Study efficiency of modern thermal insulations for buildings
Holeček, Dominik ; Skříček, Darek (referee) ; Šťastník, Stanislav (advisor)
The bachelor thesis is partly dedicated to energetic efficiency of buildings and describes possibilities how to evaluate energetic efficiency of buildings in the Czech republic. There is also detailed description of the heat transfer in buildings. We also get to know with production and characteristics of chosen thermal insulators. There are also mentioned methods how to determine thermal insulations characteristics of heat insulations, so called heat conductivity coefficient. The last and the crucial chapter of theoretic part is dedicated to thermo-reflective insulations. There are mentioned some of the basic characteristics of insulations and its material composition as well as usage and methods of thermo-reflective insulations installation in buildings. Practical part is dedicated to description of chosen samples of thermo-reflective insulations and determination of their heat resistance though Hot Box measuring method.
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Study of reflectance of materials for construction surface treatment
Rauchfussová, Karolína ; Šot, František (referee) ; Šťastník, Stanislav (advisor)
Presented work deals with the study of properties of the progressive heat-reflecting foil thermal insulating materials. The work describes the transport mechanism of thermal energy through the structure of heat-reflecting materials, physical properties are compared with conventional thermal insulating materials. It is also shown here the main applications of these materials are in the field of low-energy and passive houses, especially in terms of the optimal method of incorporating in the building. The practical part is devoted to measuring of reflectance was made and then the measuring device HOT BOX was assembled.
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Imaging Reflectometry Measuring Thin Films Optical Properties
Běhounek, Tomáš ; Spousta, Jiří (referee) ; Zicha,, Josef (referee) ; Kotačka, Libor (referee) ; Druckmüller, Miloslav (advisor)
V této práci je prezentována inovativní metoda zvaná \textit{Zobrazovací Reflektometrie}, která je založena na principu spektroskopické reflektometrie a je určena pro vyhodnocování optických vlastností tenkých vrstev .\ Spektrum odrazivosti je získáno z map intenzit zaznamenaných CCD kamerou. Každý záznam odpovídá předem nastavené vlnové délce a spektrum odrazivosti může být určeno ve zvoleném bodu nebo ve vybrané oblasti.\ Teoretický model odrazivosti se fituje na naměřená data pomocí Levenberg~-~Marquardtova algoritmu, jehož výsledky jsou optické vlastnosti vrstvy, jejich přesnost, a určení spolehlivosti dosažených výsledků pomocí analýzy citlivosti změn počátečních nastavení optimalizačního algoritmu.
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