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Portable Testing Device for In-situ Testing of Building Material
Vavřík, Daniel ; Jandejsek, Ivan
Examination of brittle buildings materials using mechanical tests requires sampling of studied elements and materials (stones, bricks or concrete). In case of existing integral structures the best suitable sampling method is core drilling. It is preferred to test samples in situ in all cases where it is possible to avoid changes of the material properties during transportation and storing. Moreover it is possible to prepare other samples operationally wen some uncertainty occurred if in situ testing is possible. For such a purpose, a portable testing device has been designed and manufactured. This device is primary devoted for so called split test technique which is based on well know testing of Brazilian disk. Analytical equation used for evaluation of the split test is based on several assumptions which have to be verified. For such verification Digital Image Correlation technique was used in our work.
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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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Small mammals in diet of barn owl in the Eastern Meditarranean
Šindelář, Jiří ; Horáček, Ivan (advisor) ; Anděra, Miloš (referee)
The extensive material of skeletal remains of mammals from a diet of barn owl in the eastern Mediterranean has been processed and evaluated with different techniques of chorological and morphometric analysis. At least 8400 individuals of 45 species of insectivores, rodents and bats were found in our total collection of samples, which represents a significant portion of fauna of the region. We have evaluated a chorological composition of the taphocoenoses and the interregional differences, manifested primarily by differences in the representation of satellite and accessory elements. We found a highly significant impoverishment of the isolated island taphocenoses (Cyprus, Karpathos, partly on Crete), where Cricetidae, Arvicolidae, C. leucodon etc. are missing. On the other hand the essential part of the dominance structure takes up the Rattus rattus, which acts here as an invasive species, significantly more successful than in the ragged continental contexts. The species diversity of the examined samples is positively correlated with the geographic latitude (taphocenoses of the northern regions are significantly richer) and negatively with the island effect and the degree of aridization. The morphometric analysis of the three most abundant species of Soricidae within the studied region showed...
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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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STRAIN ENGINEERING OF THE ELECTRONIC STRUCTURE OF 2D MATERIALS
del Corro, Elena ; Peňa-Alvarez, M. ; Morales-García, A. ; Bouša, Milan ; Řáhová, Jaroslava ; Kavan, Ladislav ; Kalbáč, Martin ; Frank, Otakar
The research on graphene has attracted much attention since its first successful preparation in 2004. It possesses many unique properties, such as an extreme stiffness and strength, high electron mobility, ballistic transport even at room temperature, superior thermal conductivity and many others. The affection for graphene was followed swiftly by a keen interest in other two dimensional materials like transition metal dichalcogenides. As has been predicted and in part proven experimentally, the electronic properties of these materials can be modified by various means. The most common ones include covalent or non-covalent chemistry, electrochemical, gate or atomic doping, or quantum confinement. None of these methods has proven universal enough in terms of the devices' characteristics or scalability. However, another approach is known mechanical strain/stress, but experiments in that direction are scarce, in spite of their high promises.\nThe primary challenge consists in the understanding of the mechanical properties of 2D materials and in the ability to quantify the lattice deformation. Several techniques can be then used to apply strain to the specimens and thus to induce changes in their electronic structure. We will review their basic concepts and some of the examples so far documented experimentally and/or theoretically.
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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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