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Effect of material moisture on mechanical properties of a FDM printed part
Matějka, Tomáš ; Zouhar, Jan (referee) ; Zemčík, Oskar (advisor)
This thesis deals with the effect of humidity to the mechanical properties of 3D FDM printed parts. The aim of the thesis was to experimentally determine the rate of infulence of humidity to the mechanical properties, according to selected tests, for 3D printed parts by FDM method. Furthermore the course of air moisture absorption over time was monitored. The thesis contains description of the machines and material used. The way in which materials absorb moisture is also described here. Based on the research were selected specific materials, PLA, ABS, PETG, ASA and Nylon PA12. Tested samples were produced on a Kossel Linear Plus 3D printer from Anycubic. First experiment dealt with weight loss due to drying and the weight change due to air mositure absorption over time. This was followed by experimental evaluation of changes in tensile properties of the samples. In the next part of the thesis the change in toughness of materials was evaluated. There were made analysis of the macrostructure of the quarries for both tests. Furthermore the hardeness change was measured depending on the presence of moisture in the original samples. A microtome cut was made to analyze the results. The last part of the work was the economic evaluation of drying processes, which resulted in specific recommendations for the storage of printing materials.
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The role of nuclear-encoded subunits of cytochrome c oxidase in mitochondrial metabolism
Čunátová, Kristýna
Mitochondria, 'the powerhouses of the cell', house the integral metabolism pathway of oxidative phosphorylation to produce the majority of cellular energy. Mammalian cytochrome c oxidase, also called complex IV (cIV), is indispensable for the overall oxidative phosphorylation function as the terminal oxidase, and for its regulation to sustain energetic needs. Since cIV is a multimeric enzyme composed of subunits encoded by nuclear and mitochondrial genomes, its biogenesis is a complicated process, which needs to be coordinated to complete a fully functional complex. Further, the setup of individual nuclear-encoded subunits isoforms of cIV may fine-tune cIV function based on the tissue or the environment context. Despite the physiological and pathological relevance of cIV composition, biogenesis, and the secondary deficiencies triggered by cIV defects, nuclear-encoded subunits' function remains poorly understood. At first, mammalian COX4 subunit isoforms with tissue- and oxygen-dependent expression were studied in the HEK293 cellular model with an exclusive expression of COX4I1 or COX4I2 isoform. Remarkably, the COX4I2 isozyme showed lower affinity to oxygen, which may imply regulation of cIV activity under hypoxia, and is of physiological relevance for the oxygen-sensing mechanism. Further,...
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The role of nuclear-encoded subunits of cytochrome c oxidase in mitochondrial metabolism
Čunátová, Kristýna ; Pecina, Petr (advisor) ; Gahura, Ondřej (referee) ; Ugalde, Cristina (referee)
Mitochondria, 'the powerhouses of the cell', house the integral metabolism pathway of oxidative phosphorylation to produce the majority of cellular energy. Mammalian cytochrome c oxidase, also called complex IV (cIV), is indispensable for the overall oxidative phosphorylation function as the terminal oxidase, and for its regulation to sustain energetic needs. Since cIV is a multimeric enzyme composed of subunits encoded by nuclear and mitochondrial genomes, its biogenesis is a complicated process, which needs to be coordinated to complete a fully functional complex. Further, the setup of individual nuclear-encoded subunits isoforms of cIV may fine-tune cIV function based on the tissue or the environment context. Despite the physiological and pathological relevance of cIV composition, biogenesis, and the secondary deficiencies triggered by cIV defects, nuclear-encoded subunits' function remains poorly understood. At first, mammalian COX4 subunit isoforms with tissue- and oxygen-dependent expression were studied in the HEK293 cellular model with an exclusive expression of COX4I1 or COX4I2 isoform. Remarkably, the COX4I2 isozyme showed lower affinity to oxygen, which may imply regulation of cIV activity under hypoxia, and is of physiological relevance for the oxygen-sensing mechanism. Further,...
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Security Risks for Critical Infrastructure in the Water Management Sector
Fošumpaurová, Anna ; Špelda, Petr (advisor) ; Střítecký, Vít (referee)
The thesis examines the security concerns connected with the critical infrastructures in the water management sector, specifically hydraulic structures comprising the drinking water supply system. The thesis focuses on systemic risk and reliability assessment as a component of contemporary principles and security practices comprising the critical infrastructure protection (CIP) framework. The foremost objective is to explore to which extent Czech domestic procedures peruse the international expertise when assessing systemic risks stemming from the dependencies and interaction of water supply chain components. Investigating the present-state risk assessment relates strongly to the policy development at the European Union level. For that reason, the thesis commits particular attention to the Council Directive 2008/114/EC and Directive (EU) 2020/2184 and their impacts on the management and operation of critical infrastructures in the water supply sector. The thesis also studies the state- of-the-art reliability assessment methods for water distribution networks. The acquired knowledge is utilised to estimate the reliability of a study distribution network using stochastic simulation and survey selected network robustness-improving solutions. The thesis identifies the critical elements of a water...
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Effect of material moisture on mechanical properties of a FDM printed part
Matějka, Tomáš ; Zouhar, Jan (referee) ; Zemčík, Oskar (advisor)
This thesis deals with the effect of humidity to the mechanical properties of 3D FDM printed parts. The aim of the thesis was to experimentally determine the rate of infulence of humidity to the mechanical properties, according to selected tests, for 3D printed parts by FDM method. Furthermore the course of air moisture absorption over time was monitored. The thesis contains description of the machines and material used. The way in which materials absorb moisture is also described here. Based on the research were selected specific materials, PLA, ABS, PETG, ASA and Nylon PA12. Tested samples were produced on a Kossel Linear Plus 3D printer from Anycubic. First experiment dealt with weight loss due to drying and the weight change due to air mositure absorption over time. This was followed by experimental evaluation of changes in tensile properties of the samples. In the next part of the thesis the change in toughness of materials was evaluated. There were made analysis of the macrostructure of the quarries for both tests. Furthermore the hardeness change was measured depending on the presence of moisture in the original samples. A microtome cut was made to analyze the results. The last part of the work was the economic evaluation of drying processes, which resulted in specific recommendations for the storage of printing materials.
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Time-scale analysis of sovereign bonds market co-movement in the EU
Šmolík, Filip ; Vácha, Lukáš (advisor) ; Krištoufek, Ladislav (referee)
The thesis analyses co-movement of 10Y sovereign bond yields of 11 EU mem- bers (Greece, Spain, Portugal, Italy, France, Germany, Netherlands, Great Britain, Belgium, Sweden and Denmark) divided into the three groups (the Core of the Eurozone, the Periphery of the Eurozone, the states outside the Eurozone). In the center of attention are changes of co-movement in the crisis period, especially near the two significant dates - the fall of Lehman Brothers (15.9.2008) and the day, when increase of Greek public deficit was announced (20.10.2009). Main contribution of the thesis is usage of alternative methodol- ogy - wavelet transformation. It allows to research how co-movement changes across scales (frequencies) and through time. Wavelet coherence is used as well as wavelet bivariate and multiple correlation. The thesis brings three main findings: (1) co-movement significantly decreased in the crisis period, but the results differ in the groups, (2) co-movement significantly differs across scales, but its heterogeneity decreased in the crisis period, (3) near to the examined dates sharp and significant decrease of wavelet correlation was observable across lower scales in some states. JEL Classification C32, C49, C58, H63 Keywords Co-movement, Wavelet Transformation, Sovereign Debt Crisis, Sovereign Bond Yields,...
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Current diversification scenarios of the Russian Federation on one side and the V4 countries on the other with respect to the interdependence theory
Záhradníková, Lea ; Holubcová, Jitka (advisor) ; Kučerová, Irah (referee)
The thesis focuses on current diversification scenarios in the field of gas supply the Visegrad Group (V4) and the Russian Federation relying on the model of asymmetrical interdependence. Russian Federation, the main supplier of natural gas to this region, has lost its status of a reliable partner due to the gas wars with Ukraine in 2006 and 2009, which have negatively affected the supply of natural gas to the EU countries. The research focuses on the current diversification options of V4 countries related to their suppliers and supply routes with respect to their relationship with the Russian Federation; the diversification options for the purchasing markets of the Russian Federation are also analyzed. The author validates the hypothesis that energy relations among the Visegrad countries and the Russian Federation in the field of gas supply are largely controlled by the asymmetric interdependence that is currently exacerbating tensions among the set actors. Current diversification scenarios are presented and evaluated, with the aim of assessing the importance of the projects with regard to actors' energy security. Keywords: interdependence, energy security, diversification, gas supply, gas interconnector, V4, Energy Union, Russian Federation, Nord Stream II, LNG
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Current diversification scenarios of the Russian Federation on one side and the V4 countries on the other with respect to the interdependence theory
Záhradníková, Lea ; Holubcová, Jitka (advisor) ; Kučerová, Irah (referee)
The thesis focuses on current diversification scenarios in the field of gas supply the Visegrad Group (V4) and the Russian Federation relying on the model of asymmetrical interdependence. Russian Federation, the main supplier of natural gas to this region, has lost its status of a reliable partner due to the gas wars with Ukraine in 2006 and 2009, which have negatively affected the supply of natural gas to the EU countries. The research focuses on the current diversification options of V4 countries related to their suppliers and supply routes with respect to their relationship with the Russian Federation; the diversification options for the purchasing markets of the Russian Federation are also analyzed. The author validates the hypothesis that energy relations among the Visegrad countries and the Russian Federation in the field of gas supply are largely controlled by the asymmetric interdependence that is currently exacerbating tensions among the set actors. Current diversification scenarios are presented and evaluated, with the aim of assessing the importance of the projects with regard to actors' energy security. Keywords: interdependence, energy security, diversification, gas supply, gas interconnector, V4, Energy Union, Russian Federation, Nord Stream II, LNG
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Interdependence and Power in EU-Russian Gas Relations
Abubakirova, Evgenia ; Svoboda, Karel (advisor) ; Young, Mitchell (referee)
The aim of this thesis is to investigate gas interdependence for political relations between the European Union and the Russian Federation. Despite of the fact that relations in the gas sphere still have particular importance for both parties, after the Ukrainian crisis, sanctions and counter-sanctions applied, they have reached the lowest point of cooperation since the end of the Cold War. This thesis is based on the interdependence model of international relations theory, asymmetries in sensitivity and vulnerability of the EU and Russia were connected to their strategies as part of the political power play. Therefore, conflict situation, high level of sensitivity and vulnerability, and interest in finding alternatives of both parties lead to the situation of 'negative interdependence'. In this context, this kind of interdependence where partners would rather avoid relations logically pushes the EU and Russia apart and stimulates reconsideration of their relationship in gas sphere.
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Impact of sovereign debt crisis in Greece on its neighboring countries
Papoušek, Radan ; Geršl, Adam (advisor) ; Kuc, Matěj (referee)
In this thesis, I analyze contagious effects stemming from Greece to Bulgaria, Cyprus, Italy, and Turkey during the Greek sovereign debt crisis. Using the VAR framework, I estimate adjusted cross-market correlation coefficients, and then test them on con- tagion. My research is based on examination of 10-year sovereign bonds and stock market indices in time period spanning from December 2004 to August 2012. The thesis finds that contagious impacts arising from the Greek crisis were present in all the examined countries. I also find significant interdependence among some of the examined countries. The existence of transmission channels suggests that the crisis could spread easily from Greece.
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