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Calculation and optimization of synchronous servomotor reluctance torque.
Kroupa, Martin ; Hájek, Vítězslav (referee) ; Ondrůšek, Čestmír (advisor)
This work is mainly focused on construction and design simulation of synchronous servomotor. This motor is built by 30 permanent magnets which are attached to rotor and solved in Ansoft Maxwell 14 software. The main purpose was to calculate reluctance torque, which is significant during the motor operational mode and its optimization. Ansoft Maxwell 14 can analyze in 2D mode as well as in 3D mode, for analysis it uses method of finite elements. Subjects can be analyzed in static conditions, or in any way of transient movement. Optimization in 2D, where we will change the shape in the area of air gap, will only be used as revision that the reluctance torque is bounded with this factor. The main simulations were supposed to be done in 3D model, where the role of rotation should have been taken in account to the final result. These simulations were replaced by alternative calculation. On behalf of achieved results, the optional rotation is stated in the end of my work.
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Transitional effects in road vehicle aerodynamics
Kroupa, Michal ; Vančura, Jan (referee) ; Čavoj, Ondřej (advisor)
This bachelor thesis deals with transient phenomena in vehicle aerodynamics with the focus on describing and proposing of unsteady mechanisms. First part investigates transient phenomena during crosswind gusts. Next part deals with unsteady pressure distribution around the vehicle during passing and overtaking manoeuvre. Final part investigates transient phenomena during dynamic pitching motion.
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CFD simulation of a crosswind gust
Kroupa, Michal ; Vančura, Jan (referee) ; Čavoj, Ondřej (advisor)
This thesis deals with the investigation of unsteady effects on vehicle that has been exposed to a crosswind gust. First crosswind velocity function was created, which is a function of both time and space. A comparison of continual and trapeze gust model was carried out. Next step was to compare unsteady and quasi-steady evolution of the aerodynamic loads using accumulated forces, surface pressures and flow field around the car. The penultimate part deals with investigation of unsteady behaviour of drag and in the last part the influence of rear geometry of the car on unsteady phenomena was investigated.
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Suggestion of a workshop lift for garden machines
Kroupa, Martin ; Kašpárek, Jaroslav (referee) ; Hloušek, David (advisor)
This bachelor thesis deals with the design of workshop lifting equipment for garden equipment. The parameters for lifting equipment were set at a load capacity of 100 kg, working table dimensions of 1200x800 mm and minimum working table height of 1200 mm. In the thesis, the static and strength calculation of the mechanism is performed and the drive is calculated, which is realized by means of a motion screw.
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Posttranlational protein modifications in response to DNA damage
Kroupa, Michal ; Hodný, Zdeněk (advisor) ; Novotný, Marian (referee)
- 5 - Abstract Thousands of DNA lessions occur in each cell every day of which the most toxic are double-strand breaks (DSBs). Signaling of their presence and subsequent repair are mediated by so-called DNA-damage response mechanism (DDR), which involves accumulation of many effector proteins into DSBs sites. These molecular accumulation at DSBs are termed DNA damage foci. Depending on presence of sister chromatid, DSBs are repaired by two major mechanisms: by homologous recombination and by non-homologous end joining. Both pathways lead to activation of checkpoint kinases (Chk1 or Chk2) which iniciate checkpoints in cell cycle and allow repair of damaged DNA. Signaling of DNA damage and activation of these pathways are regulated by posttranslational protein modifications. These enzymatic reactions involve mainly phosphorylation, ubiquitination and sumoylation. Recently it was shown that ubiquitination of damaged chromatin is a prerequisite for sumoylation of tumor supressors BRCA1 and 53BP1. Failure in DNA damage recognizing mechanisms caused by disorders such as modifications or mutations of 53BP1 and BRCA1 genes can lead to subsequent disruption of genomic integrity and then a high risk for selection of cell clones with tumorigenic potencial. Current research is focused on regulation of posttranslational...
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Chromosomal damage and DNA repair capacity in blood lymphocytes as transient markers in carcinogenesis.
Kroupa, Michal ; Vodička, Pavel (advisor) ; Štětina, Rudolf (referee)
Recent knowledge suggests that the onset of cancer is modulated by the interplay of internal and external environmental factors along with numerous gene variants. Structural chromsomal aberrations in peripheral blood lymphocytes are considered as biomarkers of effect of genotoxic carcinogens and reflect elevated risk of cancer. Incomplete or deficient repair of double-strand breaks in DNA underlie chromosomal aberrations and the measurement of cytogenetic alterations may reflect interindividual differences in the response towards the mutagen. In this study the expected deficiences in the DNA repair capacity have been determined in incident oncological patients with breast, colorectal and urogenital cancers. The determination of chromosomal aberrations have been supplemented by the measurement of variants in genes involved in double-strand breaks repair (XRCC3, rs861539; RAD54L, rs1048771). Methodologically, we employed conventional cytogenetic analysis, cytogenetic analysis following the induction of chromocomal damage by bleomycin ("Challenge assay"), TaqMan discrimination analysis for the detection of allelic variants and statistical analyses. By using these methods we did not observe statistically signifiant differences either in chromosomal breaks (p=0,354) or in a percentage of cells with...
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Reform of the IMF Real empowerment of developing countries or just a gesture?
Kroupa, Michal ; Plechanovová, Běla (advisor) ; Parízek, Michal (referee)
Recently implemented reform of the IMF was motivated by empowering smaller developing and emerging countries. My work has an ambition to assess the countries were empowered and whether there would be a more efficient way for IMF reform. I analyse of role and power of countries using well-established methodology of Voting Power Indices. Apart from the immediate change a longer perspective covering last 20 years would be implemented. My aim is not only assess the power of countries as isolated variables but also to assess them in context of other indicators such as economic development. Lastly, I would suggest a new way of reform proposal for the IMF. Currently countries are represented in the locus of executive power through constituencies. Constituencies are formed arbitrary often reflecting power-seeking behaviour of developed countries. The result is composition of constituencies that often further marginalize the developing countries. My proposal is to restructure these constituencies in line with regional international organizations, which can enhance the position of developing countries in two ways. By providing institutional capacity of already existing organizations the consensus within the constituency would be better facilitated. By formation constituencies in line with regional...
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Chromosomal damage and shortening of telomeres in cancer patients and healthy subjects
Kroupa, Michal ; Vodička, Pavel (advisor) ; Kmoníčková, Eva (referee) ; Rössner, Pavel (referee)
Impaired chromosome segregation during mitosis, inaccurate DNA damage response and excessive telomere shortening may all modulate the frequency of chromosomal aberrations (CAs) in peripheral blood lymphocytes (PBL). There is evidence that increased frequency of structural CAs in PBL may be considered as a marker of enhanced cancer risk. In the present Thesis, an effect of variants in genes involved in mitotic checkpoint and DNA damage response on the inter-individual differences in CAs frequency in PBL was investigated. Considering the importance of disrupted telomere structure and its function in cancer biology, a link between telomere length and clinicopathological and molecular features of cancer patients was analysed. Furthermore, the relevance of telomere length and CAs frequency as markers of patients' survival was examined. The major outcomes of the Thesis, fully reported in detail in seven attached Manuscripts, are: I) Increased frequency of structural CAs and/or disrupted telomere length in PBL may be considered as risk factors for the different types of solid cancer; II) Telomere shortening in PBL of healthy subjects increased the frequency of structural CAs; III) Binary interactions of gene variants in mitotic checkpoint and DNA repair pathways may modulate the frequency of structural...
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Chromosomal damage and shortening of telomeres in cancer patients and healthy subjects
Kroupa, Michal ; Vodička, Pavel (advisor) ; Kmoníčková, Eva (referee) ; Rössner, Pavel (referee)
Impaired chromosome segregation during mitosis, inaccurate DNA damage response and excessive telomere shortening may all modulate the frequency of chromosomal aberrations (CAs) in peripheral blood lymphocytes (PBL). There is evidence that increased frequency of structural CAs in PBL may be considered as a marker of enhanced cancer risk. In the present Thesis, an effect of variants in genes involved in mitotic checkpoint and DNA damage response on the inter-individual differences in CAs frequency in PBL was investigated. Considering the importance of disrupted telomere structure and its function in cancer biology, a link between telomere length and clinicopathological and molecular features of cancer patients was analysed. Furthermore, the relevance of telomere length and CAs frequency as markers of patients' survival was examined. The major outcomes of the Thesis, fully reported in detail in seven attached Manuscripts, are: I) Increased frequency of structural CAs and/or disrupted telomere length in PBL may be considered as risk factors for the different types of solid cancer; II) Telomere shortening in PBL of healthy subjects increased the frequency of structural CAs; III) Binary interactions of gene variants in mitotic checkpoint and DNA repair pathways may modulate the frequency of structural...
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