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The theme on this diploma thesis is „Changes in sensory properties of spirits due to external factors“. In the theoretical part are contained chapters on the alcohol, production of alcohol and spirits. In the practical part, an experiment was established in 2017 in which the selected spirit drink was stored in two types of bottles under different storage conditions. The spirit drink used in the experiment was the domestic rum. The diploma thesis is focused on spectrophotoscopic measurement of samples of domestic rum, for which the intensity of color changes was monitored. In addition, a sensory evaluation of the colour intensity of the samples was carried out. The measurements were carried out for one year at regular intervals. The results is obtained were statistically and graphically evaluated. The results indicates that L*(D65) a*(D65) b*(D65) varied significantly over time under different storage conditions For samples stored at 6 °C, the L*(D65) gradients increased more slowly and valeus a*(D65) and b*(D65) were decreased slowier than those stored at 20 °C. The samples that were exposed to different light modes at 20 °C also increased value L*(D65) and decrease a*(D65) and b*(D65) values. The fastest changes to these values were in samples stored under a fluorescent lamp, then under daylight, and the slowest changes were in samples that were stored in the dark. By measuring, it was found that the bottle type had a demonstrable effect on the storage of samples exposed to different light modes. In all types of the samples, the total color differentiation ΔE* ab was calculated, indicating whether the difference in color was already visible for the human senses. This was confirmed by sensory analysis.

The diploma thesis is dealing with the monitoring of quality of beef meat during the process of ageing. In the literary overview the terms beef meat and quality are defined, the consumption of beef meat is stated and the composition and attributes of the beef meat are described. The list of factors that influence the quality of beef meat follows. The factors are divided into intravital and postmortal. The postmortal processes are described more thoroughly; the possibilities and consequences of their abnormal progress and other quality defects are added. The practical part of the thesis is devoted to the comparison of chosen parameters of heifer meat (n = 6) of the Aberdeen Angus breed (AA) and Czech Fleckvieh breed (CS). In the cut-out parts Musculus longissimus dorsi (NR) and Musculus adductores (SŠ) the parameters of pH, electrical conductivity and color were observed for eight weeks of aging in the vacuum (1-2 °C). The color was measured spectrofometrically with the application of the CIELAB color space.

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The topic of my diploma thesis deals with influence rennet to quality coagulation of milk. The theoretical part consists of general information about milk and milk composition. I also focused on curdling, types rennet and principle of milk coagu-lation. Last topic of theoretical part is about whey, whey composition and nutrition and whey colour. The practical part was focused on parameters, which influence qua-lity coagulation of milk. Among them includes analysis of milk, clotting time, quality curd, volume released whey, dry matter of whey, colour whey. These parameters are compared using different rennet. I also investigated the factors that influence milk curdling. The results suggest that composition of milk was comparable with results of the central laboratory. It was also found, that amount of rennet had an influence on coagulation time and volume of whey. More rennet had an influence of quality of curd and dry matter of whey. Amount of rennet did not infulence on whey colour. Type and amount of rennet may affect on individual parameters of whey colour.

This thesis deals with conformal geometric algebra CGA for colour image processing, particularly with colour segmentation. For this reason it is not sufficient to work in RGB colour space. It is more convenient to use a colour space called CIELAB. CIELAB is endowed by Euclidean metric corresponding with human perception of colours. Afterwards an algorithm for an object detection via CGA based on colour differences is included. The final part of the thesis deals with least squares fitting of sphere to points using CGA. The sphere fitting is then used to adjust colour differences in an image to improve the algorithm for an object detection.

<p>The aim of this thesis is to develop an technical aid (software) to help people with colourblindness. Colour blind people have difficulties to differentiate between certain colours,so the implemented software will name a selected colour. The software is implementedas a Mozilla Firefox extension and also uses a XPCOM component. Furthermore canthe user select different colour databases and change the displaying properties.The aim of this thesis is to develop an technical aid (software) to help people with colourblindness. Colour blind people have difficulties to differentiate between certain colours,so the implemented software will name a selected colour. The software is implementedas a Mozilla Firefox extension and also uses a XPCOM component. Furthermore canthe user select different colour databases and change the displaying properties.</p>

>Magister Scientiae - MSc / Introduction: Together with bonding to both enamel and dentine, an ideal restorative material would display physical properties similar to that of natural tooth tissue and would not be prone to degradation as a result of the oral environment. This includes changes in colour. Glass ionomer technology has undergone many changes to its original chemistry since it was developed in the early 1970’s. In 1988 resin-modified glass ionomers were introduced and in 2008, nano-ionomers were introduced. As a result of the progression in material sciences and the use of more sophisticated techniques and methods in restorative dentistry, it is possible to accomplish much improved aesthetics and functional durability of a restoration, both anteriorly and posteriorly. However, for as long as aesthetic restorations have been available, and in spite of advances in material structure and performance, one of the greatest challenges facing clinicians still remains that aesthetic restorations have to be replaced relatively frequently as staining and discolouration is a common problem. Aim of the study: The aim of this study was to determine the stainability of four resin-modified glass ionomers and one glass ionomer cement when exposed to a staining broth. Objectives: To record any change in colour before and after exposing the sample with the staining broth using a spectrophotometer, to compare the stainability, to examine the depth of staining using a light microscope and to observe the particle size of the powder and the surface texture using Scanning Electron Microscopy of the four resin- modified glass ionomer cements and one glass ionomer cement. Materials and Methods: Four resin-modified glass ionomers (one nano-ionomer) and one glass ionomer (zinc-reinforced ionomer) were selected. All were shade A2, except for Vitremer™ which was not available in A2. 15 discs of each material were prepared. The discs were 15 mm in diameter and 2 mm in thickness. All the materials were handled and cured according to the manufacturers’ instructions. After curing, only one side of each disc was polished using Sof-Lex™ discs (3M ESPE, USA). The unpolished side of each disc was designated as a matrix finish. The specimens were all immersed in distilled water at 37 °C for one week. They were then immersed in a staining broth for a period of one week and readings were taken after a period of 2 hours, 4 hours, 8 hours, 24 hours and one week. Colour was read on each side of each disc at the indicated intervals with a spectrophotometer. The colour difference was calculated using the CIELAB colour co-ordinates. Sample discs were then sectioned to determine the depth of staining. An additional sample disc of each material was made for observation with the SEM and was therefore not stained. Also, an unmixed sample of each material was prepared for examination with the SEM. Results: In general, for all materials there was an increase in staining when assessed with the colour difference between the baseline colour and the 7 day reading. Ketac™ N100, showed the highest total colour change of 43.84 for the unpolished surface followed by Riva™ which showed the total colour change of 28.55 for the unpolished surface. This was similar to Fuji II LC® which had a total colour change of 28.16 for the unpolished surface. For Vitremer™, the total colour change increased to 18.07 for the unpolished surface. For the unpolished surfaces, ChemFil™ Rock showed the least colour difference from baseline to 7 days (ΔE*ab = 10.45), followed by Vitremer™ (ΔE*ab = 18.07). Both Fuji II LC® and Riva™ Light Cure showed similar colour change from baseline to 7 days for unpolished surfaces (ΔE*ab of 28.16 and 28.55 respectively). Ketac™ N100 showed the highest staining after 7 days in the staining broth with a colour difference of 43.84. For the polished surfaces, the colour change for Fuji II LC® was 25.72 which was similar to Riva™ Light Cure which was 22.44 and Ketac™ N100 which showed a colour change of 22.79 on the polished surface. ChemFil™ Rock showed the least colour change of 17.69 for the polished surface followed by Vitremer™ which showed a colour change of 23.63 for the polished surface. Thus, for both the unpolished and polished surfaces there was a similar staining pattern. Conclusion: In this study it was demonstrated that all products evaluated in this study showed some degree of staining when exposed to a staining broth when evaluated using the ΔE*ab CIELAB colour evaluation. Ketac™ N100 showed the highest colour change compared to the other materials, but the reason for this was not explored. Both Vitremer™ and ChemFil™ Rock showed similar patterns of staining. / 2020-09-01

The aim of this thesis is to develop an technical aid (software) to help people with colourblindness. Colour blind people have difficulties to differentiate between certain colours,so the implemented software will name a selected colour. The software is implementedas a Mozilla Firefox extension and also uses a XPCOM component. Furthermore canthe user select different colour databases and change the displaying properties.The aim of this thesis is to develop an technical aid (software) to help people with colourblindness. Colour blind people have difficulties to differentiate between certain colours,so the implemented software will name a selected colour. The software is implementedas a Mozilla Firefox extension and also uses a XPCOM component. Furthermore canthe user select different colour databases and change the displaying properties.