This thesis focuses on the description and detection of service degradation of engine oil in agricultural technology. The first part is an introduction to lubricants. Followed by an overview of the classification of motor oils according to their composition and viscosity. In other chapters the thesis deals with the the issue of lubrication of internal combustion engines and further clarification of the causes of penetration of wear particles in the engine. The experimental part of the work examines the motor oil used in the tractor Zetor. Oil samples were taken at intervals of 50 hours . In the beginning there are described the methods and appliances used to determine parameters of the samples . Final results are processed and show in charts. Their valuesdetermine the coefficients of determination R2. A total of eight samples of engine oil MADIT M7 ADS III were used. Seven of the samples were taken from the oil tank of the tractor and one sample was brand new. For these samples the chemical composition was examined as well as the amount of wear particles in the oil . Furthermore, the density and dynamic viscosity were meas-sured. Kinematic viscosity was calculated based on these two parameters. The state of degradation of engine oil was finally determined from all of these results.

In this thesis "Growth dynamic and yield production of maize grown under different row spacing" was observed a field experiment conducted in 2013 -- 2014 on the Experimental Field Station in Žabčice. The experiment was aimed on comparison of growth dynamic and yields of forage maize grown under narrow rows (0,35 m), traditional rows (0,75 m) and twin-rows in variants with different seed rates. Results were influenced by extremely different weather conditions in each of the observed year. In the year with low precipitations from July to the harvest (2013) was observed statistically significant increase of yields in case of variants with narrow rows and twin-row in comparison to traditional row distance. In 2014 during these months was enough precipitation and differences between variants were minimal.

The diploma thesis is focused on qualitative evaluation degradation of gear oils . The first part is an introduction to lubricants, gear oil and their properties, composition and classification. Followed by an overview of the classification of automatic transmission discussion of selected types and their function. The experimental part of diploma thesis deals with examining sample of gear oil. Density and viscosity was measured for all samples of gear oil. By atomic emission spectrometry was measured metals in oil. There is a description consumption all samples of gear oil, description of the tested car, method and instruments which were used for determining degradation of gear oil. The results of individual samples of gear oil are shown in graphs and is discussed rate of oil degradation.

The purpose of diploma thesis was evaluate the effect of milk production an the season on the quality colostrum Czech fleckvieh cattle in a selected breeding. Between monitored parameters were included solids, active acidity, density, imunoglobulins content and refraction. Literary review was processed to the given problem. Viewed samples came from the farm Agrodružstvo Tištín. Samples were taken during the whole year (from 17. 4. 2014 to 18. 1. 2015). In this period has been taken 39 samples of colostrum, from selected cows. These cows were all on the second lactation. The measured values were statistically processed. The results indicate, that cows with high milk production have better quality of colostrum. Seasons affected the quality of colostrum. The cows, who gave birth in the autumn and winter, had colostrum quality. We found, that healthy cows had in colostrum more immunoglobulins and solids, during the assessing the health condition.

The aim of this study was to determine the population density of deer in the area Křivoklátsko. To detect a population density was used counting dung piles. The work is also characteristic of the whole monitored area, and the deer (Cervus elaphus), which Krivoklatsko abundant. This work also discussed the various census followed by a focus on the method of counting dung piles. Furthermore, it evaluates the incidence not only of deer in forests and damages, as well as the presence of sika deer (Cervus nippon), roe deer (Capreolus capreolus), wild boar (Sus scrofa) and fallow deer (Dama dama) and damage them caused. In this study also highlighted the amount of catch deer in both areas, compared with known population density of deer. In the discussion we discussed the pros and cons of methods of counting dung piles and accuracy of results.

The aim of the thesis is the determination of the spring and summer wood percentage, annual ring´s width and conventional density of the chosen woody plants and its dependence on the trunk´s level. For these purposes were researched 9 different trees. It was taken 10 wooden segments from the each chosen level of the trunk. It was chosen program WinDendro and it was made dendrochronological analyses and measurement of the spring and summer wood. It was used Olson´s mathematics figure for the conventional density calculation. In this calculation it is always used maximum level of the wood volume. The outcome is the number which is almost realistic figure of the conventional density change and structure change of the annuals´ rings. These outcomes are measured in the transection and cross section.

The theoretical part of the thesis: Physical properties of liquid fuels and bio diesel for combustion engines is aimed at describing the physical properties of fuels and ra-peseed oil methyl ester. It includes familiarization with the issue of dynamic viscosity and density of internal combustion engines and a comprehensive overview of methods of measuring these quantities . Experimental work is devoted to experimental measurement of the temperature de-pendence of the dynamic viscosity and density of selected diesel samples with different concentrations of rapeseed oil methyl ester. The measurement results were processed into tables containing diagrams .

Diploma thesis in its theoretical part solves the problems of the milk assortment of dairy products, especially yogurt. It splits yogurt to the different types describing their production and chemical and physical properties. It is followed by a chapter devoted to the physical characteristics of foods, as well as their rheological properties, specifically viscosity. The practical part deals with the rheological properties of specific samples of commercially available yogurt. For these seven samples was determined by the density and the viscosity and shear stress versus shear rate. To assemble the flow and viscosity curves were used Ostwald-de Waeleho model, thanks to him, it was subsequently decided what kind of fluid as, Newton viscosity law, in the case of yogurt is. For the samples was determined as well as the time and temperature dependence of viscosity. Selected samples were analyzed fat content, which can be compared with data on the packaging of the sample.

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