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Design of mobile horizontal wood-splitting machine
Dressler, Jan ; Škopán, Miroslav (referee) ; Knoflíček, Radek (advisor)
This thesis shows making of documentation for production powerfull wood-splitting machine for hardest forestal work. There are researched and soluted all phases of pre-production machine's lifecycle, also means analysis of conception, potentional risks and failures analysis and also definition of required properties. Based on those properties and results of analyses is possible to setting up condition which should be satisfied. At following part are descripted and shown features of machine-design . Main feature (component) of machine is its frame, also there are strenght analysis of frame. Machine movement features are mainly hydraulics pistons which are powered by asynchronous engine, whith alternative possibility movement by wheel tractor power-take off shaft or hydraulics output. There are performed all important properties. Working safety questions and high endurability of machine shold be also performed. At the end of work is realised conception and design study of forestal production system for wood processing with one universal source of energy – wheeled tractor.
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Parametric testing plasma welding on the root of weld
Záškoda, David ; Daněk, Ladislav (referee) ; Kubíček, Jaroslav (advisor)
The subject of this thesis is to assess the suitability of the new process of welding roots of welds by the rotors of steam turbines plasma jet. The new proposed method uses a combination of welding the weld root plasma with the method of submerged-arc welding, however the submerged-arc welding is not subjekt of this work. The tests performed were verified by the possibility of welding the weld root of the plasma jet – Keyhole method without filler material. The aim was to find the optimum welding parameters to achieve the required weld quality, particularly with regard to geometry of weld. Turbine rotors are made of heat resistant steels, which have high strength at high temperatures. In all described tests have been used steel 30CrMoNiV 5-11....Mat. No. 1.6946.
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Physical Load Analysis In Woman's Beach Volleyball
Maciolková, Hana ; Vorálek, Rostislav (advisor) ; Buchtel, Jaroslav (referee)
Title: Physical Load Analysis In Woman's Beach Volleyball Objectives: The objective is to examine time characteristics, cardiac strain, movement pattern and the individua! volleyball skills in woman playing beach volleyball. The results will help aid athletes and coaches to improve individua} and team performance in the sport. Methods: Analyses of the thirteen game records were used to compile data for statistical time measurements, movement pattems and individua! volleyball skill. Through the use of sport testers, four individua} athletes in four separate toumaments had their heart rates recorded. These heart rates were further analyzed to collect the appropriate data for cardiac strain characteristics. Results: The average game time was 37 minutes with 5 - 9 seconds exercise loads and 15 seconds recovery time. Beach volleyball is high to middle level intensity game with mixed aerobic- anaerobic energy supply system in use. The average heart rate falls in the interval of 150 and 180. The jumping load is about 41 and more jumps counting serve jump, block and spike. The prevalent movement distance is within 4 meter range. The results also shows that the blocking player is under large physical stress while changing repeteadly position between defence on the net and in the field. Keywords: Beach...
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Fyzikálně-chemická charakterizace peptidů a bílkovin kapilárními elektromigračními metodami
Kašička, Václav ; Koval, Dušan ; Šolínová, Veronika ; Sázelová, Petra ; Prusík, Zdeněk
High-performance capillary electromigration methods, zone electrophoresis, isotachophoresis, isoelectric focusing, affinity electrophoresis and electrokinetic chromatography, are presented as powerful tools for physicochemical characterization of peptides and proteins.
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Vodní a hybridní plazmatrony s plynovou a vodní stabilizací
Hrabovský, Milan
Plasma torches with water-stabilized arc (Gerdien arc) are utilized in plasma processing for specific applications. In water-stabilized torches an oxygen-hydrogen plasma jet is produced. The torches are characterized by very low mass flow rates and high power. Plasma enthalpy is thus several times higher than enthalpy of plasmas generated in gas-stabilized torches. High enthalpy is accompanied by very low plasma density. Also other plasma parameters substantially differ from the ones in gas torches. New type of plasma torch with combined stabilization of an electric arc by water vortex and gas flow was investigated. This hybrid water/gas stabilization offers possibility of adjustment of plasma jet parameters in a wide range from high enthalpy, low density plasmas typical for liquid stabilized torches to lower enthalpy, higher density plasmas generated in gas stabilized torches.
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Diffraction efficiency of surface relief gratings
Hradil, Milan
Diffraction efficiency of surface-relief gratings with various profiles is discussed. The general relation for the diffraction efficiency is derived from the Frauenhoffer approximation. The general relation is applied for several profiles. It is pointed out that shallow profiles can provide high diffraction efficiencies.
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Use of Interest Rate Models for Interest Rate Risk Management in the Czech Financial Market Environment
Cíchová Králová, Dana ; Arlt, Josef (advisor) ; Cipra, Tomáš (referee) ; Witzany, Jiří (referee)
The main goal of this thesis is to suggest an appropriate approach to interest rate risk modeling in the Czech financial market environment in various situations. Three distinct periods are analyzed. These periods, which are the period before the global financial crisis, period during the financial crisis and in the aftermath of the global financial crisis and calming subsequent debt crisis in the eurozone, are characterized by different evaluation of liquidity and credit risk, different relationship between financial variables and market participants and different degree of market regulations. Within this goal, an application of the BGM model in the Czech financial market environment is crucial. Use of the BGM model for the purpose of predicting a dynamics of a yield curve is not very common. This is firstly due to the fact that primary use of this model is a valuation of interest rate derivatives while ensuring the absence of arbitrage and secondly its application is relatively difficult. Nevertheless, I apply the BGM model to obtain predictions of the probability distributions of interest rates in the Czech and eurozone market environment, because its complexity, direct modeling of a yield curve based on market rates and especially a possibility of parameter estimation based on current swaptions volatilities quotations may lead to a significant improvement of predictions. This improvement was also confirmed in this thesis. Use of swaptions volatilities market quotations is especially useful in the period of unprecedented mone- tary easing and increased number of central banks and other regulators interventions into financial markets that occur after the financial crisis, because it reflects current market expectations which also include future interventions. As a consequence of underdevelopment of the Czech financial market there are no market quotations of Czech koruna denominated swaptions volatilities. I suggest their approximations based on quotations of euro denominated swaptions volatilities and also using volatilities of koruna and euro forward rates. Use of this approach ensures that predictions of the Czech yield curve dynamics contain current market expectations. To my knowledge, any other author has not presented similar application of the BGM model in the Czech financial market environment. In this thesis I further predict a Czech and Euro area money market yield curve dynamics using the CIR and the GP models as representatives of various types of interest rates models to compare these predictions with BGM predictions. I suggest a comprehensive system of three criteria, based on comparison of predicti- ons with reality, to describe a predictive power of selected models and an appropria- teness of their use in the Czech market environment during different situations in the market. This analysis shows that predictions of the Czech money market yield curve dynamics based on the BGM model demonstrate high predictive power and the best 8 quality in comparison with other models. GP model also produces relatively good qua- lity predictions. Conversely, predictions based on the CIR model as a representative of short rate model family completely failed when describing reality. In a situation when the economy allows negative rates and there is simultaneously a significant likelihood of their implementation, I recommend to obtain predictions of Czech money market yield curve dynamics using GP model which allows existence of negative interest rates. This analysis also contains a statistical test for validating the predictive power of each model and information on other tests. Berkowitz test rejects a hypothesis of accurate predictions for each model. However, this fact is common in real data testing even when using relatively good model. This fact is especially caused by difficult fulfilment of test conditions in real world. To my knowledge, such an analysis of the predictive power of selected interest rate models moreover in the Czech financial market environment has not been published yet. The last goal of this thesis is to suggest an appropriate approach to obtaining pre- dictions of Czech government bonds risk premium dynamics. I define this risk premium as a difference between government bond yields and fixed rate of CZK IRS with the same length. I apply the GP model to describe the dynamics of this indicator of the Czech Republic credit risk. In order to obtain a time series of the risk premium which are necessary for estimation of GP model parameters I firstly estimate yield curves of Czech government bonds using Svensson model for each trading day since 2005. Resulting si- mulations of risk premium show that the GP model predicts the real development of risk premiums of all maturities relatively well. Hence, the proposed approach is suitable for modeling of Czech Republic credit risk based on the use of information extracted from financial markets. I have not registered proposed approach to risk premium modeling moreover in the Czech financial market environment in other publications.
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Impact of low oil and natural gas prices on the economy of Qatar since 2014
Šamánek, Ondřej ; Stuchlíková, Zuzana (advisor) ; Hasík, Gabriel (referee)
The bachelor thesis examines the impact of the oil and gas prices slump, which befell the world in 2014, on the economy of Qatar. The main objective of the thesis is to evaluate if and to what extend the price collapse influenced the relevant economic indicators and behaviour of the state and companies active in the affected field. The selected objective is examined using the method of data comparison, namely before and after the price slump, and with the help of the case study, in which the qatari company operating in the oil and gas is examined. From the conducted analysis it is possible to conclude that Qatar was directly influenced by the oil and gas prices collapse: its GDP slumped, fiscal deficit increased. The analysed company also experienced troubles caused by low prices: one year after the price slump, total amount of assigned tenders to company decreased substantially and historically high number of tenders was cancelled. Conclusions deriving from the thesis might be applied to other oil and gas export economies in the Persian Gulf, for fundamental traits of such economies are shared with the economy of Qatar.
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Ellipsometry of Thin Films
Novotný, Zbyněk ; Navrátil, Karel (referee) ; Nebojsa, Alois (advisor)
Diploma thesis deals with ageing process of thin films of Co and Cu on Si substrate, prepared by the IBAD method. The process of film ageing, which depends on time of exposition to the atmosphere at room conditions, was investigated with spectroscopic ellipsometry (VIS+UV) and atomic force microscopy. In case of thin Co films, approximately four days long incubation period was observed. During this time period, a change in the optical parameters of the film occurs without a measurable change of the film topography. Using non-contact atomic force microscopy, a growth of the transitional film in the island growth regime was observed. During the ageing of thin Cu films, two stages of growth of the transitional layer were observed - nucleation stage and growth stage. Both of these time periods of the transitional layer growth show direct logarithmic dependence. Using non-contact atomic force microscopy, the growth of the transitional film was observed. Using atomic force microscopy in non-contact regime, time dependent measurement was done and the process of forming of one monolayer of the transitional layer was documented. Within the diploma thesis, a series of experiments on ultra high vacuum system were performed in order to investigate phase transformation of thin Fe films (22 monolayers) on Cu(100) stabilized by CO absorption. The transformation from fcc phase to bcc phase was induced by Ar+ ion beam bombardment with the ion energy in the range (0.5-4) keV. The process of phase transformation was observed by surface magneto-optic Kerr effect, Auger electron spectroscopy and low energy electron diffraction.
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