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Computational modelling of the low-profile flexible support of the pad of journal bearing
Kudláčová, Martina ; Pavlík, Ondřej (referee) ; Pokorný, Jan (advisor)
Aerodynamic tilting pad journal bearings are currently one of the most widely used bearing types in high-speed rotary devices. In order to ensure better rotor stability under harsh operating conditions, research is underway on a new type of aerodynamic bearings with flexible support of tilt pads. The first chapters of this thesis are focused on an overview of bearing theory with a focus on aerodynamic bearings. The thesis presents the current state of research in the field of aerodynamic foil bearings and aerodynamic tilting pad journal bearings with an emphasis on pad support options. The aim of the final thesis is to determine the geometry of the low-profile flexible support of the pads for a specified bearing using computational modeling. A computational model was created, the results of which were verified experimentally using the method of digital image correlation (DIC). A parametric study was carried out using a computational model which allowed a comprehensive view of the issue of the dependence of the support parameters of the segment on its force and stiffness. Based on the results of the parametric study, the geometry of the low-profile flexible support of the pads for the specified bearing was determined.
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Images of Hassidic Jews in Olbracht's, Langer's and Hostovský's Literary Works
Pavlík, Ondřej ; Holý, Jiří (advisor) ; Merhaut, Luboš (referee)
This bachelor thesis aims to compare how the Hasidic tale is adapted in three literary works, all originally published in the year 1937: Děvět bran by Jiří Langer, Golet v údolí by Ivan Olbracht, and Dům bez pána by Egon Hostovský. Its first part tries to characterize the genre of the Hasidic tale and describe how it was first showcased in Czech when published on the pages of Czech-language Jewish periodicals. Its second part focuses on the specific ways how the Hasidic tale was integrated into all three aforementioned works and what influence this had on the meaning of the texts. Key words Ivan Olbracht, Jiří Mordechaj Langer, Egon Hostovský, Martin Buber, Devět bran, Golet v údolí, Dům bez pána, Jewish periodicals, Hasidism, Hasidic tale
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Design of the composite rotor sleeve of a high speed rotary machine
Pavlík, Ondřej ; Ševeček, Oldřich (referee) ; Návrat, Tomáš (advisor)
The diploma thesis focuses on manufacturing carbon fiber and epoxy composite material using filament winding method. Material properties of manufactured composite are ap-proximated using analytical and numerical homogenization models. Calculated material properties are applied to design and evaluate reserve factor of retaining sleeve for high speed brushless permanent magnet synchronous motor. Margin of safety of designed rotor is evaluated using composite failure criteria. Test stand for both static and dynamic testing is designed, static test stand is manufactured and assembled. Static strength test is carried out.
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Trade mark law and the issues of parallel imports under Czech law
Pavlík, Ondřej ; Dobřichovský, Tomáš (advisor) ; Wünschová Pujmanová, Alexandra (referee)
The purpose of the thesis is to analyse the phenomenon of parallel imports, define the pros and cons of parallel trade for respective entities and also society as a whole as well as describe how the trademark law may influence parallel importation of trademarked goods. In addition, the thesis analyses individual means of legal protection against parallel imports identified as illegal. After the introduction summarizing why it is appropriate to deal with the parallel importation phenomenon, the second part of the thesis describes the basic concepts in the context of parallel import issues: trademarks, parallel imports and exhaustion of trademark rights. The second part also describes the positive and negative impacts of parallel trade and why the doctrine of exhaustion of trademark rights appears to be the most appropriate way how to solve the difficulties in the relationship between trademark owners and parallel importers. The third part of the thesis aims to provide a reader with the basic sources of law which affect the phenomenon of parallel importation from the trademark law's point of view. As it follows from the third part of the thesis and also the whole work, the key legal source for the European region, including the Czech Republic, is the law of the European Union together with the case...
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Stress-Strain Calculations of Selected Components of Firearm
Pavlík, Ondřej ; Ševeček, Oldřich (referee) ; Slažanský, Martin (advisor)
Thesis deals with the utilization of the finite element method (FEM) in development of computational model. Subject of the computational model is the slide stop pin of the pistol CZ 75, designed and manufactured in Czech Republic by Česká zbrojovka Uherský Brod. The computational model describes strain stress analysis of the slide stop pin. The results of the analysis are subject to difficult sourcing of relevant and reliable input information. Based on stress strain analysis results, the safety factor of the pin was determined. However, the results are influenced a lot by input parameters selection. At the conclusion the summary of proposed further steps for computational model accuracy increase is proposed.
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DC/AC inverter for small asynchronous machine
Pavlík, Ondřej ; Patočka, Miroslav (referee) ; Červinka, Dalibor (advisor)
The aim of this Bachelor thesis is to propose three-phase converter of low power 100W for driving the asynchronous motor. The device is suitable for construction with fans. This proposal was optimized in light of close price and of technical practicability. The arrangement is possible to use in less exacting applications where it was guarded high price of common converters so far. For allocation catalogue scheme were chosen acceptable components and designed the board of printed circuits.
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Mathematical models of retention object of urban drainage
Pavlík, Ondřej ; Stanko,, Ing Štefan (referee) ; Pollert,, Jaroslav (referee) ; Prax, Petr (advisor)
This work deals with the use of 3D mathematical models of fluid in water management practice. Using 3D mathematical model was assessed retention tank Jeneweinova, which is situated on a sewer network of the city of Brno and is an important object of urban drainage. Retention basin designed to keep overflow from CSO chambers to Svratka and Svitavský náhon during storm events. Retention tank Jeneweinova is suitable for the assessment, because tank was designed bassed the Master Plan drainage of Brno using 1D mathematical model. Another factor was the physical model, which was build in LVV Vin FAST BUT. And finally, near the retention tank will be installed measurement on the sewerage network, which will be able to verify the results whitch has been predicted in this work. Mathematical model of retention tanks Jeneweinova was build in software FLOW-3D. FLOW-3D is a general purpose CFD (Computational Fluid Dynamics) software for flow of fluid in steady and unsteady mode and uses computational techniques to solve the equations of motion of fluids. This software is mainly used for the calculation of hydraulic fluids, gas flow and heat transfer simulations. Results from 3D mathematical model has been compared with the values in the physical and 1D mathematical model.
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Neutralization of acid solutions
Pavlík, Ondřej ; Bébar, Ladislav (referee) ; Jícha, Jaroslav (advisor)
The present thesis is concerned with neutralization of acid groundwater after the hydrochemical uranium mining in the area of Stráž pod Ralskem. In the thesis is briefly described progression of the hydrochemical uranium mining and follow-up negative impacts on the environment. There is described the technology involved in its disposal. This is followed by the design calculation of major apparatus technology associated with neutralization of acid solutions. Output of technology is determined by the mass balance. The results are the main dimensions of the apparatus, mechanical parts and electric power each device.
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Frequency inverter for small induction machine
Pavlík, Ondřej ; Procházka, Petr (referee) ; Červinka, Dalibor (advisor)
The aim of this diploma thesis is to continue in prototype realization and a final proposition of three-phase frequency transformer pilot projected in scope of my bachelor work. This transformer is outlined for a small unsynchronized engine to 100 watt output and is designed to supply the fan motor. This suggestion was optimalized from the standpoint of bargain low price and technical feasibility. Powerful part of transformer is solved with help of circuit FSB50450 which is fed from compact source MYRRA 47155. Steering system is guaranteed with circuit MC3PHAC. This device is possible to use in less demanding applications where it was resisted by high expensive price of common frequency transformers.
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Realization of the plastic holder of the car navigation
Pavlík, Ondřej ; Nohál, Libor (referee) ; Paloušek, David (advisor)
The goal of this bachelor´s thesis is suggestion and manufacture of the plastic holder of the car navigation. The literature retrieval part contains gathering of information about external holders of the car navigations and description of prototype manufacturing method. The construction part is an accompanying report of suggestion and manufacturing of the car holder. 3D CAD Model is created in parametric modeller via Autodesk Inventor Professional 2010. The holder is then made via Rapid Prototyping FDM technology.
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