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Material of electrodes for electrical discharge machining
Bednář, Šimon ; Chladil, Josef (referee) ; Osička, Karel (advisor)
Diplomová práce se zabývá problematikou volby grafitového materiálu využívaného pro výrobu nástrojových elektrod při elektroerozivní obrábění. Práce je rozdělena do třech částí. Teoretická rešerše nekonvenční technologie elektroerozivního obrábění vypracovaná dle uvedených zdrojů se nachází v první části práce. Dále je v práci proveden cenový průzkum EDM grafitových materiálů nabízených v České republice a na Slovensku. Čtyři odlišné stupně kvality grafitu (od stávajícího dodavatele firmy GAMARTIS TRADE s.r.o.) a jeden měděný materiál byly podrobeny experimentu, jehož účelem bylo zjištění závislosti mezi kvalitou grafitového materiálu (cena) a přesností vyhloubené kavity, opotřebením nástrojové elektrody, časem obrábění nebo také drsností povrchu.
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High-speed Machining of Bearings from Material 100Cr6
Tropp, Pavel ; Osička, Karel (referee) ; Sedlák, Josef (advisor)
This Master's thesis deals with the issue of high-speed turning of the 100Cr6 material. The aim is to identify and experimentally validate an innovative production process for a particular component. The thesis includes theoretical basis of high-speed machining, analysis of the current state of the manufacturing process, innovation design and experimental verification. At the end of the thesis, parameters of the machined surfaces of specimens are evaluated.
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Analysis of modern milling technologies for shaped parts
Pavelek, Michal ; Kalivoda, Milan (referee) ; Zemčík, Oskar (advisor)
The aim of my bachelor thesis is the analysis of modern milling technologies for shaped parts. The work offers the categorization and definition of shaped parts, and a description of the characteristics of milling techniques and methods used in the production of shaped parts. The work also describes the machines and tools used in the process of milling shaped parts. The last part of the paper offers the evaluation of each analyzed method, their comparing, and points out both their advantages and disadvantages.
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Studying the properties of high strength concrete using micro and nano admixtures
Gabko, Miroslav ; Bodnárová, Lenka (referee) ; Hela, Rudolf (advisor)
The objective of this bachelor thesis is to examine the properties of high strength concretes with the main focus on application of mikro or nano admixtures. In theoretical part their production, the properties and the influence on fresh and hardened properties of cement composites are described. In addition, it explores the influence of plasticizer type, some properties of aggregate and cement types. The practical part focuses on testing cement mortars in which fine cements were added. The compressive and flexural strengths were examined after 7 and 28 days of curing, moreover, rheological properties and heat hydration of cements were also observed. Furthermore, the influence of high speed mixing on cement mortars properties was studied.
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Stroje pro vysokorychlostní obrábění
Šlajs, Zdeněk
This bachelor thesis deals with the concept of high-speed machining (HSC) and with the characteristic features of this modern chip machining method. The aim is to briefly explain the use and technological aspects of the technology. The first part of the bachelor thesis explains the basic terms of chip machining necessary for understanding the relevant issue. It also explains the principles and compositions of numerically controlled machine-tools. The next part explains the differences between high-speed and conventional machining. It focuses on the characteristics aspects of high-speed machining and its cutting conditions. The part of bachelor thesis is also treatise on the use of HSC machining centers. There are the advantages and disadvantages summarized at the end.
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Hematopoiesis in the models of zebrafish and medaka as a recipient for human HSC xenograft
Pravcová, Naďa ; Drbal, Karel (advisor) ; Svoboda, Ondřej (referee)
Danio rerio (zebrafish) and Oryzias latipes (medaka) have recently become popular model organisms to study hematopoiesis. These model organisms present several advantages in comparison to other commonly used models, the most common being Mus musculus (mouse). The advantages are shorter generation time, large offspring production, frequent spawning, external fertilization and development, the optical transparency of embryos amenable to genetic manipulation on the background of vast numbers of transgenic lines (mainly in zebrafish) and inbred strains (in medaka). Moreover, most of the mechanisms behind zebrafish and medaka hematopoiesis are conserved in higher vertebrates. Most importantly, the optical transparency in early development and in adult mutant transparent strains allows for observation of hematopoietic stem cell (HSC) development in vivo. Therefore, it is possible to generate humanized fish using xenotransplanted human HSCs for studies of the engraftment, differentiation, and trafficking of human HSC in vivo. Currently, the most popular organism for human HSC xenotransplantation is mice. This model system is not suitable for in vivo imaging of HSC engraftment. Moreover, a prior immunodepletion step is necessary. The process of immunodepletion includes genetic manipulation or irradiation...
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Material of electrodes for electrical discharge machining
Bednář, Šimon ; Chladil, Josef (referee) ; Osička, Karel (advisor)
Diplomová práce se zabývá problematikou volby grafitového materiálu využívaného pro výrobu nástrojových elektrod při elektroerozivní obrábění. Práce je rozdělena do třech částí. Teoretická rešerše nekonvenční technologie elektroerozivního obrábění vypracovaná dle uvedených zdrojů se nachází v první části práce. Dále je v práci proveden cenový průzkum EDM grafitových materiálů nabízených v České republice a na Slovensku. Čtyři odlišné stupně kvality grafitu (od stávajícího dodavatele firmy GAMARTIS TRADE s.r.o.) a jeden měděný materiál byly podrobeny experimentu, jehož účelem bylo zjištění závislosti mezi kvalitou grafitového materiálu (cena) a přesností vyhloubené kavity, opotřebením nástrojové elektrody, časem obrábění nebo také drsností povrchu.
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Origins of vertebrate hematiopoiesis
Svoboda, Ondřej ; Bartůněk, Petr (advisor) ; Divoký, Vladimír (referee) ; Živný, Jan (referee)
(ENGLISH) Hematopoiesis is dependent on the actions of hematopoietic stem cells (HSCs). This process is tightly controlled through a complex array of extrinsic and intrinsic factors. Even though the hematopoiesis seems to be well conserved across the disparate vertebrate animals, erythroid and thrombocytic differentiation have changed during the evolution of mammals. Specifically, adult mammalian red blood cells have the unique feature of being enucleated, and mammalian thrombocytes are not individual cells, but fragments of megakaryocytes, instead. It is likely that these enhancements provided a survival advantage to early mammalian species; however, they also bring up the question of evolutionary origin of these cells that studied using zebrafish (Danio rerio) model. First, it was necessary to generate a toolbox of a recombinant cytokines and optimized culture media that allowed us to manipulate zebrafish hematopoietic cells ex vivo in liquid and clonal cultures. Interestingly, teleost species underwent an extra duplication event during their evolution and as a result, two copies (paralogs) of some of the genes are present in zebrafish. This was also the case for majority of the cytokines from our toolbox and here, we provide functional characterization of these paralogs. Strikingly, our results...
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High-speed Machining of Bearings from Material 100Cr6
Tropp, Pavel ; Osička, Karel (referee) ; Sedlák, Josef (advisor)
This Master's thesis deals with the issue of high-speed turning of the 100Cr6 material. The aim is to identify and experimentally validate an innovative production process for a particular component. The thesis includes theoretical basis of high-speed machining, analysis of the current state of the manufacturing process, innovation design and experimental verification. At the end of the thesis, parameters of the machined surfaces of specimens are evaluated.
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Analysis of modern milling technologies for shaped parts
Pavelek, Michal ; Kalivoda, Milan (referee) ; Zemčík, Oskar (advisor)
The aim of my bachelor thesis is the analysis of modern milling technologies for shaped parts. The work offers the categorization and definition of shaped parts, and a description of the characteristics of milling techniques and methods used in the production of shaped parts. The work also describes the machines and tools used in the process of milling shaped parts. The last part of the paper offers the evaluation of each analyzed method, their comparing, and points out both their advantages and disadvantages.
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