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Experimental Investigation of Accelerator Driven Nuclear Reactors for Thorium Based Nuclear Power
Zeman, Miroslav ; ČR,, Milan Štefánik, UJF AV (referee) ; Katovský, Karel (advisor)
The Master Thesis deals with the use of thorium nuclear fuel in accelerator driven systems. Basic principle of ADS, present situation and future possibilities are described in this work. The main goal of the work is determination of neutron flux in spallation target QUINTA. In December 2013, an experiment was performed at Joint Institute for Nuclear Research, Dubna. Samples of cobalt, situated at different positions in QUINTA target, were irradiated in secondary neutron field generated by deuteron beam of energies 2 AGeV and 4 AGeV and beam of C-12 with energy 2 AGeV. The samples were measured with the use of germanium semiconductor detectors and analysed using gamma-ray spectrometry. Reaction rates of Co-59 products were determined. Neutron flux was determined in setup QUINTA on the base of experimental reaction rates. Experimental reaction rates were compared with calcula1tion of MCNPX code.
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Experimental Investigation of the Neutron Field in an Accelerator Driven Subcritical Reactor
Zeman, Miroslav ; Janda,, Jiří (referee) ; Chudoba,, Petr (referee) ; Katovský, Karel (advisor)
This dissertation focuses on irradiations of a spallation set-up consisting of more than half a ton of natural uranium that were executed by a 660 MeV proton beam at the Joint Institute for Nuclear Reserch in Dubna. Two types of irradiations were arranged: with and without lead shielding. Both types were arranged with threshold activation detectors (Al-27, Mn-55, Co-59, and In-nat) located throughout the whole set-up both in horizontal and vertical positions and activated by secondary neutrons produced by spallation reaction. The threshold activation detectors were analysed by the method of gamma-ray spectroscopy. Radionuclides found in the threshold detectors were analysed and reaction rates were determined for each radionuclide. Ratios of the reaction rates were determined from irradiation of the set-up with and without lead shielding. Subsequently, the neutron spectra generated inside the spallation target at different positions were calculated using Co-59 detector. The experimental results were compared with Monte Carlo simulations performed using MCNPX 2.7.0.
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Photopolymerization kinetics of dimethacrylate dental resin
Vaněk, Martin ; Bystřický, Zdeněk (referee) ; Poláček, Petr (advisor)
Aim of magister´s thesis was to study reaction kinetics of dental materials. Thesis was focused on dimethacrylate dental polymers, which are for example used for dental restoration, tooth repair and creating now teeth. First part of the thesis concentrates on influence of molar ratio on reation kinetics by addition of other monomer to polymer resin. Second part concentrates on influence of addition of additive silica on reaction kinetics of polymerization. Essential variables know as a polymerization ratio, conversion, gel point, glass transition temperature and storage modulus were studied. Firstly, polymerization ratio and conversion were observed by differential scanning calorimetry (DSC). Secondly rheology was observed by photoreometr. Finally, glass transition temperature and storage modulus were observed by dynamic mechanical analysis (DMA). Behaviour changes caused by addion of monomer or filler point out decrease of polymeration ratio and converstion. Same behaviour was observed by short exposure. In order to established network formation, values of gel point increased by higher concentration of monomer or filler. Glass transition temperature and storage modulus measured by DMA were evaluated. Those valuables had variable tendency due to monomer acting like filler at higher concentration. Also contradictory impact of different material conversion and filler concetration was discussed.
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Anticipation sources for goalkeeper during a penalty kick in football
Kraus, Tomáš ; Carboch, Jan (advisor) ; Vampola, Jindřich (referee)
Title: Anticipatory sources of football goalkeepers when facing penalty kicks Objectives: The aim of the bachelor's thesis is to investigate what anticipatory cues professional soccer goalkeepers perceive and take into account when facing a penalty kick. Methods: The bachelor thesis employed a qualitative research design, specifically a case study. Professional and semi-professional football goalkeepers playing in the second and third highest Czech football leagues were selected as participants. All goalkeepers are currently active players, with ages ranging from 22 to 27. The interview method was used, consisting of 16 questions and lasting approximately 20-30 minutes, during which the players reflected on key factors related to the topic of anticipation in football goalkeepers during penalty kicks. The second phase of the research involved transcription of the interviews and their analysis. Results: The bachelor thesis described individual topics that highlight additional sources of anticipation explored by football goalkeepers during penalty situations. Football goalkeepers examine various contextual and kinematic information sources that assist them in anticipating shots during standard situations. It is also evident that goalkeepers do not fully utilize the potential of anticipation, which can...
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Circadian sleep preferences of children of older school age practicing karate.
ROUDNICKÁ, Lenka
The aim of my bachelor thesis was to find out circadian sleep preferences of older school-age children practising karate. In the theoretical part of the bachelor thesis, I deal with the sleep problems of older school-age children, where I define important terms, which are: circadian rhythms, speed abilities, specifics of sports preparation of children practising karate. Circadian rhythms affect the bodily functions of our body within twenty-four hours. Speed abilities are one of the most important abilities which are involved in the athlete's final performance. The specifics od sports training for children practising karate depend on the age, sex, level, motivation and determination of the athlete. Older school-age i sone of the most important parts of life. There is a formation of the mental and physical aspects of man. The practical part was realized using a standardized questionnaire of the composite scale of morning and evening types Skočovský (2004), which was filled by 40 children (20 boys, 20 girls) of older school-age from 11 to 15 years. Based on the evaluation of the questionnaire, the aim of the work was fulfilled and I came to the following most important data: 15 % of boys are morning types or larks, 65 % of boys are neutral or third birds and 20 % of boys are evening types or owls. I also found that 40 % od girls are morning types, 55 % of girls are third birds and 5 % of girls are evening types.
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How to find the rate of border stress in the survival drill
Heřmánek, Jaroslav ; Barták, Erik (advisor) ; Majerčík, Petr (referee)
AABBSSTTRRAACCTT TTiittllee:: How to find the border stress in the survival drill PPuurrppoossee:: Purpose of this master thesis is to find acceptable instruments for determination of border stress in the survival drill. MMeetthhooddss:: This master thesis was worked up as empiric quantitative research observation type. We have tested 16 probands. For testing we used four motoric tests which were prepared to find actual stress of probands, psychological test OPTIM and in the second course hematologic research. RReessuullttss:: Measured values demonstrate possible connection in two motoric tests where the results are getting worse in border stress and in the extreme stress. In rest two tests there was not proved any connection between the results of tests and stress. KKeeyy wwoorrddss:: Actual stress, stress, soft motorics, equilibrium abilitiy, reaction ability, action ability, tapping rate.
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Comparison of reaction rate in children diagnosed with ADHD and common population of the same age
Kovařovic, Vojtěch ; Nováková, Tereza (advisor) ; Vomáčková, Helena (referee)
Title: Differences in reaction rate in children with ADHD and the general population of the same age. Problem definition: ADHD is a neuropsychological disorder occurring in part of the pediatric population (5-8%). The scientific public mentions the existence of the so-called hyperfocus, ie the ability to significantly concentrate in children diagnosed with ADHD, especially in the case of these children being interested in the task. Methodologically correctly compiled and performed testing of the reaction rate of these children could confirm or refute this assumption. Aims: The aim of the work is to find out whether and possibly what effect the diagnosis of ADHD in children has on the reaction rate. Hypotheses: H1: The reaction rate in individuals with ADHD will be on average the same or higher than in individuals of the same age of the healthy population. H2: The difference between the individual experiments will be greater in children with ADHD than in individuals of the same age of the healthy population. H3: The individual with fastest reaction ability with ADHD will have the same or better result as the individual with the fastest reaction of the same aged healthy population. Methods: Testing for the purposes of this diploma thesis took place in the ROSA center. 12 probands in the tested group...
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Experimental Investigation of the Neutron Field in an Accelerator Driven Subcritical Reactor
Zeman, Miroslav ; Janda,, Jiří (referee) ; Chudoba,, Petr (referee) ; Katovský, Karel (advisor)
This dissertation focuses on irradiations of a spallation set-up consisting of more than half a ton of natural uranium that were executed by a 660 MeV proton beam at the Joint Institute for Nuclear Reserch in Dubna. Two types of irradiations were arranged: with and without lead shielding. Both types were arranged with threshold activation detectors (Al-27, Mn-55, Co-59, and In-nat) located throughout the whole set-up both in horizontal and vertical positions and activated by secondary neutrons produced by spallation reaction. The threshold activation detectors were analysed by the method of gamma-ray spectroscopy. Radionuclides found in the threshold detectors were analysed and reaction rates were determined for each radionuclide. Ratios of the reaction rates were determined from irradiation of the set-up with and without lead shielding. Subsequently, the neutron spectra generated inside the spallation target at different positions were calculated using Co-59 detector. The experimental results were compared with Monte Carlo simulations performed using MCNPX 2.7.0.
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Photopolymerization kinetics of dimethacrylate dental resin
Vaněk, Martin ; Bystřický, Zdeněk (referee) ; Poláček, Petr (advisor)
Aim of magister´s thesis was to study reaction kinetics of dental materials. Thesis was focused on dimethacrylate dental polymers, which are for example used for dental restoration, tooth repair and creating now teeth. First part of the thesis concentrates on influence of molar ratio on reation kinetics by addition of other monomer to polymer resin. Second part concentrates on influence of addition of additive silica on reaction kinetics of polymerization. Essential variables know as a polymerization ratio, conversion, gel point, glass transition temperature and storage modulus were studied. Firstly, polymerization ratio and conversion were observed by differential scanning calorimetry (DSC). Secondly rheology was observed by photoreometr. Finally, glass transition temperature and storage modulus were observed by dynamic mechanical analysis (DMA). Behaviour changes caused by addion of monomer or filler point out decrease of polymeration ratio and converstion. Same behaviour was observed by short exposure. In order to established network formation, values of gel point increased by higher concentration of monomer or filler. Glass transition temperature and storage modulus measured by DMA were evaluated. Those valuables had variable tendency due to monomer acting like filler at higher concentration. Also contradictory impact of different material conversion and filler concetration was discussed.
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How to find the rate of border stress in the survival drill
Heřmánek, Jaroslav ; Barták, Erik (advisor) ; Majerčík, Petr (referee)
AABBSSTTRRAACCTT TTiittllee:: How to find the border stress in the survival drill PPuurrppoossee:: Purpose of this master thesis is to find acceptable instruments for determination of border stress in the survival drill. MMeetthhooddss:: This master thesis was worked up as empiric quantitative research observation type. We have tested 16 probands. For testing we used four motoric tests which were prepared to find actual stress of probands, psychological test OPTIM and in the second course hematologic research. RReessuullttss:: Measured values demonstrate possible connection in two motoric tests where the results are getting worse in border stress and in the extreme stress. In rest two tests there was not proved any connection between the results of tests and stress. KKeeyy wwoorrddss:: Actual stress, stress, soft motorics, equilibrium abilitiy, reaction ability, action ability, tapping rate.
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