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The use of specimen loss factor as fatigue damage indicator of Hastelloy-X substrates with different surface treatments was investigated together with other fatigue damage indicators, namely resonance frequency and crack mouth length. The tested surface treatments included grit-blasting and plasma spraying of NiCoCrAlY bond coat and yttria stabilized zirconia (YSZ) top coat. The loss factors of fatigue test specimens were measured repeatedly during the resonance bending fatigue test using the conventional free decay method. The analysis of the damping spectra, i.e. the model describing the relation of loss factor to maximum macroscopic specimen strain εyy was drafted. The model is based on the combination of defect models developed by Göken and Riehemann (2004) and classical dislocation model of Granato and LÃŒcke (1956). It appears, that the damping spectra can be well approximated as a combination of two defect peaks (C1 and C2) and one dislocation peak (D1). The low strain defect peak (peak C1) is sensitive to the presence of fatigue cracks. The second defect peak (peak C2) can be attributed to the remaining substrate and coating defects such as embedded grit particles, coating porosity, surface roughness and sliding in the sample clamping area. The fatigue damage detection using the C1 peak magnitude was performed and its results were related to the crack length obtained by digital image correlation (DIC) method. In the crack initiation stage I., the C1 peak height shows different behavior than the resonance frequency and therefore provides new information. The underlying processes causing C1 peak changes need to be found yet, however. In the crack growth stage II., both resonance frequency and peak height C1 correlate with the measured fatigue crack size., Fundrs: Czech Science Foundation, GAČR 14-36566G.

The use of specimen loss factor as fatigue damage indicator of Hastelloy-X substrates with different surface treatments was investigated together with other fatigue damage indicators, namely resonance frequency and crack mouth length. The tested surface treatments included grit-blasting and plasma spraying of NiCoCrAlY bond coat and yttria stabilized zirconia (YSZ) top coat. The loss factors of fatigue test specimens were measured repeatedly during the resonance bending fatigue test using the conventional free decay method. The analysis of the damping spectra, i.e. the model describing the relation of loss factor to maximum macroscopic specimen strain εyy was drafted. The model is based on the combination of defect models developed by Göken and Riehemann [1] and classical dislocation model of Granato and LÌcke [2]. It appears, that the damping spectra can be well approximated as a combination of two defect peaks (C1 and C2) and one dislocation peak (D1). The low strain defect peak (peak C1) is sensitive to the presence of fatigue cracks. The second defect peak (peak C2) can be attributed to the remaining substrate and coating defects such as embedded grit particles, coating porosity, surface roughness and sliding in the sample clamping area. The fatigue damage detection using the C1 peak magnitude was performed and its results were related to the crack length obtained by digital image correlation (DIC) method. In the crack initiation stage I., the C1 peak height shows different behavior than the resonance frequency and therefore provides new information. The underlying processes causing C1 peak changes need to be found yet, however. In the crack growth stage II., both resonance frequency and peak height C1 correlate with the measured fatigue crack size.

Bakalářská práce se zabývá investováním na devizovém trhu. Popisuje současný stav u vybraných měnových párů a charakterizuje jejich chování. Navrhuje efektivní postup elektronického obchodování za použití obchodní platformy. Vysvětluje jak funguje technická a fundamentální analýza. Hlavní důraz je kladen na technickou analýzu a její technické indikátory. V návrhu popisuje rozhodovací metody, které nám říkají, kdy máme vstoupit do trhu a kdy z něho naopak vystoupit tak, abychom maximalizovali naše zisky a minimalizovali ztráty., This bachelor’s thesis engages in investing in the foregin exchange market. It desribes recent portfolio of chosen currency pairs and characterizis their behaviour. It proposes an effective method of electronic trading using the trading platform. It explains how technical and fundamental analysis work. The main vehemence is layed on technical analysis and it’s technical indicators. In it’s concept it describes the decesive methods, which give us the signals when to open a trade and when to get out of it, in order to maximise our profits and minimise our losses.

Cílem této diplomové práce je navrhnout podnikatelský záměr pro rozvoj elektronického obchodu prodávajícího japonské kuchyňské nože. Teoretická část popisuje formy podnikání, způsob sestavování podnikatelského záměru a náležitosti založení elektronického obchodu. V analytické části je popsán současný stav obchodu Jakuno a situace e-komerce v České republice. Závěr práce se zabývá již samotným podnikatelským záměrem a předkládá svoje návrhy pro zlepšení výkonnosti podniku., The goal of this master’s thesis is to suggest a business plan of development for e - shop expansion, that sells japanese kitchen knives. The theoretical part describes the forms of business, the method of composing a business plan and the requirements for establishing an e – shop. In the analytical part, the contemporary situation of the e – shop Jakuno is described and the situation of e-commerce in Czech Repulic as well. The conclusion of this thesis deals with the business plan itself and proposes its suggestions for improving the company efficiency.