Extruded fibers ovality measurement

Důležitým sledovaným parametrem při výrobě extrudovaného vlákna je jeho průměr. Měření této veličiny lze provést za předpokladu kruhovitosti jeho průřezu pomocí jedné snímací kamery. V praxi se ukázalo, že dalším důležitým parametrem je také ovalita, tedy jak moc je vlákno zploštělé. V tomto textu se tak bude předpokládat obecnější tvar průřezu vlákna a to ve tvaru elipsy. K určení ovality je potom zapotřebí již alespoň tří různých pohledů na zkoumané vlákno. Práce se zabývá zejména analytickým popisem měření ovality vlákna, konkrétně pomocí dvou rozdílných přístupů založených na principech lineární algebry a projektivní geometrie. Z tohoto důvodu je velká část práce věnována právě těmto odvětvím matematiky, zvláště se pak zaměřuje na analytickou teorii kuželoseček. Kromě toho práce obsahuje i krátkou zmínku o technickém provedení měření ovality a jeho možných úskalích.One of the important parameters observed during extruded fibre fabrication is its diameter. The diameter can be measured with a single scanning camera assuming that the fibre section has a circular shape. As proved in practice, another important parameter is ovality, that is the rate of fibre flattening. This paper assumes that the fibre section shape is elliptical. In such a case, at least three different views on examined fibre are needed. This paper deals with analytical description of fibre ovality measurement using two different approaches based on the principles of linear algebra and projective geometry. As a result, a considerable part of the work is devoted to these branches of mathematics with particular regard to analytical conics theory. Additionally, the work contains a brief mention of technical realization of ovality measurement and its possible difficulties.

The Effect of Low Air Temperature on Behaviour and Milk Production in Holstein Dairy Cows

The aim of this study was to evaluate the influence of low air temperature on behaviour and milk production in Holstein dairy cows. The experiment was carried out at a Mendel University Farm in Žabčice, CZ, between 06-12-16 and 28-02-17. The average outdoor temperature during the above mentioned period was 2.3 oC and the average barn temperature was 1.8 oC. Other known microclimatic parametres were (in average values): relative humidity (56.9 %), refrigerating quantity (37.3 W.m-2), light intensity (326.7 lx), and air flow (0.1 - 0.4 m.sMINUS SIGN 1). The values were always measured at 10:00 am. In the experiment, 75 Holstein dairy cows were observed. These cows were housed in free-stall housing stable in which the number of boxes was higher than the number of housed cows there. The observed dairy cows were either standing (43.8 %) or lying (56.2 %). In case, they were standing, the most of them were found at trough (50.4 %), less of them were found in corridor (30.0 %), and the least of them were found in their boxes. In case, the dairy cows were lying, it was found more of them were lying on their left body side (58.7 %) and less on their right body side (43.8 %). The number of dairy cows standing in boxes had a decreasing character. Concerning the daily milk yield values, these had the same trend as the barn temperature, i.e., in 9 out of 11 cases. In this case (temperature range), the amoung of daily milk yield seems to be the best assessment factor for the infuence of temperature. It is necessary to dedicate attention to air temperature range, in which the experiment was carried out.O

The two-track railway bridge

Diplomová práce se zabývá návrhem železničního mostu v Ústí nad Labem. Délka mostu je 200,00 m, výška nosné konstrukce je 32,61 m a šířka nosné konstrukce je 12,10 m. Hlavní nosný systém je tvořen prostorovou příhradovou konstrukcí. Most převádí významnou železniční trať mezi nádražími Ústí nad Labem Západ a Ústí nad Labem Střekov. Součástí návrhu je lávka pro pěší.Master´s thesis describes the design of the railway bridge in Ústí nad Labem. Length of the structure is 200.00 meters, the height of the structure is 32.61 m and width of the structure is 12.10 m. Main structural system is composed of a spatial strut-frame structures. The bridge carries an important railway stations between Usti nad Labem Západ, Usti nad Labem Střekov. Part of the proposal is a footbridge for pedestrians.

Ovality measurement of extruded fiber using three cameras

Důležitým parametrem sledovaným při výrobě extrudovaného vlákna je jeho průměr. Měření této veličiny lze provést za předpokladu kruhovitosti jeho průřezu pomocí jedné snímací kamery. V praxi se ukázalo, že dalším důležitým parametrem je také ovalita, tedy jak moc je vlákno zploštělé. V tomto textu se tak bude předpokládat obecnější tvar průřezu vlákna, a to ve tvaru elipsy. K určení ovality je potom zapotřebí již alespoň tří různých pohledů na zkoumané vlákno. Matematická část práce se zabývá především analytickým popisem měření ovality vlákna, konkrétně pomocí dvou rozdílných přístupů založených na poznatcích lineární algebry, projektivní geometrie a teorie kuželoseček. Hlavním cílem práce je pak tuto teorii společně s metodami obrazové analýzy využít k určení ovality a průměru vlákna z jejich snímků. Přesný výpočet těchto veličin je ale podmíněný přesnou kalibrací kamerového systému, kterému práce také věnuje pozornost. Kromě toho obsahuje i krátkou zmínku o technickém provedení měření ovality a jeho možných úskalích.One of the important parameters observed during extruded fibre fabrication is its diameter. The diameter can be measured with a single scanning camera assuming that the fibre section has a circular shape. As proved in practice, another important parameter is ovality, that is the rate of fibre flattening. This paper assumes that the fibre section shape is elliptical. In such a case, at least three different views on examined fibre are needed. Mathematical part of this paper is concerned with analytical description of fibre ovality measurement using two different approaches based on the knowledge of linear algebra, projective geometry and conic sections theory. Main goal of this paper is thus to use both mathematical theory and image analysis methods for ovality and diameter determination. Precise calcluation of such quantities is, however, conditioned on precise camera system calibration, which is described in the paper as well. Additionally, the work contains a brief mention of technical realization of ovality measurement and its possible difficulties.

Security Conception of Brno Turany Airport

V diplomové práci se zabývám vylepšením bezpečnostního systému na mezinárodním letišti Brno-Tuřany. Provádím rozbor aktuálních legislativních požadavků na bezpečnost s popisem problematiky letišť v EU. Definuji požadavky na bezpečnostní prvky a analyzuji letiště Brno-Tuřany. V poslední části navrhuji systémy zabezpečení s využitím moderních technologických prostředků a doporučení k zajištění bezpečnosti.In my thesis I address improvement of safety system of an international airport in Brno-Turany. I perform an analysis of current legislative safety needs and description of EU airport issues. I define particular safety requirements in reference to Brno-Turany airport. In the last part of my paper I suggest safety system that takes advantage of up to date technologies and recommendation to secure safety.

Analysis of Sulfur Poisoning on a PEM Fuel Cell Electrode

The extent of irreversible deactivation of Pt towards hydrogen oxidation reaction (HOR) due to sulfur adsorption and subsequent electrochemical oxidation is quantified in a functional PEM fuel cell. At 70 {\deg}C, sequential hydrogen sulfide (H2S) exposure and electrochemical oxidation experiments indicate that as much as 6% of total Pt sites are deactivated per monolayer sulfur adsorption at open circuit potential of a PEM fuel cell followed by its removal. The extent of such deactivation is much higher when the electrode is exposed to H2S when the fuel cell is operating at a finite load, and is dependent on the local overpotential and the duration of exposure. Regardless of this deactivation, the H2/O2 polarization curves obtained on post-recovery electrodes do not show performance losses suggesting that such performance curves alone cannot be used to assess the extent of recovery due to sulfur poisoning. A concise mechanism for the adsorption and electro-oxidation of H2S on Pt anode is presented. H2S dissociatively adsorbs onto Pt as two different sulfur species and at intermediate oxidation potentials, undergoes electro-oxidation to sulfur and then to sulfur dioxide (SO2). This mechanism is validated by charge balances between hydrogen desorption and sulfur electro-oxidation on Pt. The ignition potential for sulfur oxidation decreases with increase in temperature, which coupled with faster electro-oxidation kinetics result in the easier removal of adsorbed sulfur at higher temperatures. Furthermore, the adsorption potential is found to influence sulfur coverage of an electrode exposed to H2S. As an implication, the local potential of a PEM fuel cell anode exposed to H2S contaminated fuel should be kept below the equilibrium potential for sulfur oxidation to prevent irreversible loss of Pt sites.Comment: 28 pages, 15 figure

Optimization of Working Space in the Cabin of Rapid Intervention Fire Fighting Truck

Import 29/09/2010Diplomová práce se zabývá určením pracovního prostoru rukou v požárním automobilu pro sedícího hasiče. Na počátku práce jsou rozebrány podmínkami, které ovlivňují pracovní prostředí člověka a jak jej mohou negativně ovlivňovat. Poté je věnována pozornost parametrům lidského těla a také pracovnímu prostředí hasiče, ve kterém nejčastěji provádí svou činnost. Následně jsou již vybrány antropometrické parametry, provedeno měření a vyhodnocen tento rozsáhlý statistický soubor. Na základě těchto zpracovaných dat je již možno zobrazit optimální pracovní prostor pro ruce hasiče.Thesis deals with determination of workplace for arms in fire fighting truck for sitting fireman. At the beginning of work are taken into parts conditions, that affect man working environment and how they may negatively affect it. After it is devoted attention to parameters of the human bodies as well as fireman working environment, in which he most often does his activity. Subsequently are chosen anthropometric characteristics, metering is effected and teamed this extensive statistical set. On the basis of these processed data it is possible to display optimum working room for fireman hands.Prezenční030 - Katedra požární ochrany a ochrany obyvatelstvavelmi dobř

Pilot Study on Predictive Traits of Fresh Maize Hybrids for Estimating Milk and Biogas Production

Farmers need information on which maize hybrid is best and under what conditions. They demand that this information be clear, simple and easily understood. This study aims to estimate the potential for milk production (MPP) and the biochemical methane potential (BMP) production from fresh maize hybrids. Using these indicators from fresh maize, information on the differences between hybrids can be effectively obtained, albeit with some of the shortcomings of this proposed method. Samples of fresh maize plants (n = 384) from four hybrids were evaluated at two locations over four consecutive years (from 2018 to 2021). The dry matter content, averaged across all hybrids, all years and both locations, was 371 ± 42.3 g.kg−1. The colder and wetter the year, the significantly higher the starch content, lower the amylase-treated neutral detergent fibre content (aNDF) and lower the crude protein (CP), which was reflected in lower BMP. Weather did not significantly affect the net energy of lactation (NEL) or MPP values. The location significantly affected all monitored indicators, except BMP. The earlier the hybrid was at harvest time, the lower the NEL and MPP but the higher BMP contents were. This study is preliminary and must be repeated with more hybrids and under more different conditions