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Study of behavior of concrete and cement based composite materials exposed to high temperatures
Bodnárová, L. ; Horák, D. ; Válek, J. ; Hela, R. ; Sitek, Libor
The paper describes possibilities of observation of behaviour of concrete and cement based composite material exposed to high temperatures. Nowadays, for large-scale tests of behaviour of concrete exposed to high temperatures, testing devices of certified fire testing stations in the Czech Republic and surrounding states are used. These tests are quite expensive. For experimental verification of smaller test specimens, a testing device was built at the Technical University in Brno, where tests of thermal loading of concrete tests specimens of various sizes can be carried out (dimensions up to 800 x 800 x 800 mm or slabs up to 1100 mm of length). The testing device opens new ways of observation of behaviour of concrete and cement based composite materials exposed to high temperatures as well as preparation of specimens for observation of interaction of water jet and concrete degraded by action of high temperatures.
Fulltext: content.csg -  DOC
Plný tet: UGN_0398264 - DOC
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The creation of videotutorials for the University of Economics, Prague
Zeman, Ondřej ; Šedivá, Zuzana (advisor) ; Kupec, Michael (referee)
The purpose of this bachelor thesis is to acquaint readers with new possibilities of teaching by using information technology and its application, when making learning material. The main outputs of this thesis are video tutorials, which serve as an education support for the course 4IT110 Use MS Excel in business practice taught in the University of Economics, Prague. However, it may be useful to other students of different courses. The process of making tutorials is described from the very beginning by specifying methodology, creating model exercises, subsequent testing of tutorials by students and optimisation of videos according to their suggestions and comments.
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Potential of IoT in Smart City
Pavlíček, Tomáš ; Gála, Libor (advisor) ; Basl, Josef (referee)
The aim of this masters thesis is to identify, in which phase of adoption of Internet of Things (IoT) application areas of concept Smart City are nowadays Czech regional cities, what is their outlook to 2025 and also identify in which dimensions of concept Smart city, supported by IoT technologies, perceive Czech regional cities the greatest potential. Based on information obtained from the studied materials, the concept of Internet of Things (IoT) is described, along with a detailed description of one of its application area, namely Smart City. This area is further divided into specific dimensions, that cover specific application areas which can, through internet technology, support things in a special way. With these insights, the questionnaire (built on identified IoT application areas of smart city) was developed. Thesis should be beneficial for all towns in the Czech Republic, because it provides a comprehensive view of individual IoT application areas of concept Smart City including information on which of these IoT application areas are currently focusing regional cities, and on which they want to focus to the future. On the other hand, the survey results could also be beneficial for commercial entities, which focus on IoT implementation in cities. These entities will be able to recognise which IoT products are currently best for cities.
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Expected development of Business Intelligence applications in the coming years
Aschmann, Jakub ; Pour, Jan (advisor) ; Fortinová, Jana (referee)
This thesis focuses on the development of Business Intelligence applications. The main area is the potential development in the coming years, history of business intelligence and individual components. To acquire the necessary knowledge, I studied educational materials and electronic publications. In Chapter 3 I focus on the definition of BI, in the following chapter I analyse individual components and the last chapter is dedicated to the development in the future. This thesis will provide comprehensive knowledge and trends in business intelligence to readers who are interested in this area and are looking for complex information.
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Optimalization of material flow in automotive industry
Kolář, Tomáš ; Jirsák, Petr (advisor) ; Vinš, Marek (referee)
This master thesis is focussed on optimalization of material flow in an automotive company. First part introduce theoretical background. Automotive industry and its actual trends on global markets. Follows short introduction of the company where project of this thesis was executed. Main theoretical part describes concept of lean management, its tools in practical examples, but it is also focussed on philosophical approach to the work and mindset of the company. Follows the aplication part based on theoretical background. The whole project of this master thesis is focussed on specific area called PC store. At first this area is showed in context of overall material flow. Shortly there are introduced processes and areas where full material packaging flows. Follows deeper analysis and optimalization of PC store itself. There are three approaches of stock and lead time reduction applied. Last part shows the comparison of initial and future state including performed changes.
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Changes in structure and phase composition in the surface of tram rail
Švábenská, Eva ; Roupcová, Pavla ; Schneeweiss, Oldřich
We have investigated structure and phase composition of surface layer of tram rails after long time running and the results were compared with those obtained on the original part of material. Changes due to effects of severe plastic deformation together with thermal shocks by friction process were expected. The information about structure and phase composition was obtained by optical and scanning electron microscopy, X-Ray Powder Diffraction, Mössbauer Spectroscopy and Glow Discharge Emission Spectroscopy (GDOES) and this was completed by microhardness measurements. The results show that the surface layer in comparison with the original material exhibits important changes in grain structure, an increase in microhardness and high content of iron oxide and hydrooxides. According to the depth profile of the chemical composition measured by GDOES there is an increase in carbon content in the surface layer which can be effect of up-hill diffusion.
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HYDROGEN ABSORPTION IN A-Co30Fe55B15
Čermák, Jiří ; Král, Lubomír ; Roupcová, Pavla
Hydrogen solved in amorphous alloys (AAs) influences their magnetic characteristics. AAs are also perspective\nas additives that can improve hydrogen storage kinetic in certain types of ball-milled hydrogen storage\nmaterials (HSMs). Therefore, knowledge of hydrogen solubility and hydrogen sorption kinetics in AAs are of a\ngreat importance for aimed design both AAs with optimal magnetic parameters and HSMs with desired sorption\ncharacteristics. In the present paper, amorphous alloy Co30Fe55B15 (an example of the type a-TM1xTM2y Bz ;\nTM - transition metal) was investigated. Hydrogen concentration c H was measured by Sieverts method in\ntemperature interval from T = 150 °C to T = 350 °C under hydrogen pressure p up to 6 MPa. It was found that\nc H was an increasing function of p and its maximum value was typically 0.5 wt.% H2 at 350 °C and 6 MPa.\nHowever, when the alloy was preliminary hydrogen charged (PHC), the pressure dependence of total c Htot in\nthe first absorption cycle(s) is non-monotonous in dependence on PHC conditions. For the sake of comparison,\nthe same absorption characteristics were measured also in Mg2Ni intermetallic that is a common constituent\nin Mg-based HSMs. Comparing Co30Fe55B15 and Mg2Ni, it was concluded that Co30Fe55B15 shows lower\nhydrogen solubility, but much better absorption kinetics.
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ELECTRON BEAM REMELTING OF PLASMA SPRAYED ALUMINA COATINGS
Matějíček, Jiří ; Veverka, J. ; Čížek, J. ; Kouřil, J.
Plasma sprayed alumina coatings find numerous applications in various fields, where they enhance the properties of the base material. Examples include thermal barriers, wear resistance, electrical insulation, and diffusion and corrosion barriers. A typical structure of plasma sprayed coatings, containing a multitude of voids and imperfectly bonded interfaces, gives them unique properties - particularly low thermal conductivity, high strain tolerance, etc. However, for certain applications such as permeation barriers or wear resistance, these voids may be detrimental.\nThis paper reports on the first experiments with remelting of plasma sprayed alumina coatings by electron beam technology, with the purpose of densifying the coatings and thereby eliminating the voids. Throughout the study, several parameters of the e-beam device were varied - beam current, traverse velocity and number of passes. The treated coatings were observed by light and electron microscopy and the thickness, structure and surface morphology of the remelted layer were determined and correlated with the process parameters. Based on the first series of experiments, the e-beam settings leading to dense and smooth remelted layer of sufficient thickness were obtained. In this layer, a change of phase composition and a marked increase in hardness were observed.\n
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Black Chromia Coatings on Metal Tubes for the Solar Collectors
Brožek, V. ; Mastný, L. ; Novák, M. ; Vilémová, Monika ; Kubatík, Tomáš František
This paper describes the results of the first phase of the study preparation, structure and properties of coatings modification of black chromium oxide on copper, aluminium, iron and zirconium tubes for solar collectors. The coatings are prepared by plasma spraying of liquid chromate method which is known as liquid precursor plasma spraying. Coatings have the function of an energy trap for thermal radiation wavelengths of 1 μm – 3 μm i.e. in the IR region. At the same time, the coating increases the corrosion resistance of metal substrates. The nanometric structure and thickness of the coating depend of the feeding distance and the concentration of chromate precursors. For the deposition of nanometric splats of melt chromiumIII oxide, a new type of feeder that injects precursors into the water stabilized thermal plasma produced by the WSP® generator has been\ndeveloped.\n
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