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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Rizika spojená se zapojením jednotek sboru dobrovolných hasičů obcí do monitorování radiační situace / Risks Related to Involving the Voluntary Fire-fighter Units in the Radiation Situation Monitoring

Myslíková, Veronika January 2020 (has links)
This diploma thesis focuses on the analyzing the current state of monitoring the radiation situation by volunteer firefighters units in the emergency planning area in Dukovany nuclear power plant surroundings. The process of measurement is divided into preparation for radiation leakage and application of learned procedures in the case of the occurred radiation leakage. The aim is to identify the dangers in the current process as well as the possible risks in the case of radiation emergency by risk analysis. Based on this analysis, improvements suggestions will be made. These measures will be evaluated by their applicability and their economic value. The system of monitoring by voluntary firefighters will be compared with another monitoring system, which can be also used. The result of the analysis will be a more effective way of monitoring, including safety of the firefighter and less financial complexity.
82

Výroba utahováku matice oběžného kola čerpadla / Manufacture of nut tightening device for reactor cooling pump's impeller

Rygl, Filip January 2020 (has links)
This thesis solves the problem of design and production of a special mounting device for the impeller nut of the main circulation pump GCN-317. The proposed device is intended to solve the problems associated with the mounting and dismounting of this nut. The work provides basic information about the Dukovany Nuclear Power Plant and VVER-440 systems in general, including their brief history. It also introduces the operational and legislative environment of the primary circuit of the nuclear power plant. It deals with the task and technical description of the main circulation pump and its overhaul. The following sections present the basic principles of construction of the device and an overview of its components with a description of their purpose and method of production. The last part of the thesis describes the function of the device and its verification and reports on its deployment.
83

Návrh komunikační strategie / Proposal of Communication Strategy

Konečný, David January 2021 (has links)
This diploma thesis deals with the elaboration of proposals or improvements in marketing communication of the Dukovany nuclear power plant. The thesis is divided into three main parts. The first part includes necessary theoretical resources for building a communication strategy. The second part comprises of various analyses, which are necessary to obtain information for the concluding part of the thesis. The proposal of the communication strategy itself is based on conclusions of the analyses focused on communication of the operator of the Dukovany NPP and on the selected communication tools currently used by this power plant. It is also based on the data acquired from the quantitative survey conducted with the purpose of finding out the actual public perception of the Dukovany NPP amongst young people and their attitude towards nuclear energy in general.
84

Koncepční návrh sekundárního a terciálního okruhu pro nový jaderný zdroj / Conceptual design of secondary and tertiary circuit for a new nuclear source

Valíček, Roman January 2021 (has links)
The aim of this thesis is to create a conceptual design of the secondary and tertiary circuit of a new nuclear power plant in our country, which is preceded by a brief search of particular generations of nuclear reactors. The VVER-1200 reactor became the model for the new nuclear power plant. There was designed a heat diagram containing primary components in this work. After that, there was the balance calculation and calculation of parameters of the main devices of the proposed scheme such as condenser, low-pressure and high-pressure regeneration exchangers and steam generator.
85

Analýza připojení nového zdroje do soustavy / New Resources Connection Analysis to Power System

Galuszka, Jakub January 2009 (has links)
This dissertation deals with the idea of annexing a new nuclear resource in the locality of the Dukovany Nuclear Power Plant and the way of its connection to the power system. The main aim of this dissertation is to design concrete solution of the connection of the new resource to a certain point of the power system and complete this design by means of chosen calculation. According to the task, this dissertation consists of three parts. The first part describes the current engineering solution of the main one line diagram of our two existing nuclear power plants and generally of chosen types of power plants abroad, too. There is also a design of the internal consumption of the nuclear power plants. The objective of the second part of this dissertation is to present the survey of the power and dispositional variants of the new resource in view and mainly assess general possibilities of its connection. Using all information from the preceding part, the third part presents the concrete design of the engineering solution of the connection of the new resource to the power system and also the calculation of parameters of block transmission line. Another dissertation named “Study of Slavětice Distribution Substation Enlargement for EDU New Resources“ concurs this part or more precisely, my dissertation as a whole . For my dissertation I have used some materials and information from the ČEZ Corporation which are confidential. I have also used some knowledge from the analysis from the EGÚ Brno Corporation. This dissertation neither represents nor substitutes a complex analysis of all aspects of a new nuclear resource in the Dukovany Nuclear Power Plant.
86

Studium vlastností hyperpolarizovaného xenonu-129 pro zobrazování magnetickou rezonancí / Study of the properties of hyperpolarized xenon-129 for magnetic resonance imaging

Rychnovský, Jan January 2009 (has links)
Produkce hyperpolarizovaných plynů, především helia (3He) nebo xenonu (129Xe), nachází stále rostoucí rozsah aplikací v zobrazování magnetickou rezonancí (MRI). Helium ani xenon nejsou obyčejně obsaženy v těle a experimenty tedy nejsou ovlivněny nechtěným signálem z okolních tkání. Ukázalo se, že několika hyperpolarizačními technikami může být magnetická polarizace (magnetizace) jader vzácných plynů zvýšena na hladinu, se kterou jsou praktické aplikace proveditelné. Hyperpolarizované plyny mohou tedy být užitečným nástrojem pro neinvazivní zkoumání lidského dýchání, dovolující statické zobrazování během zadržení dechu nebo zkoumání dynamiky výdechu nebo nádechu, nebo funkčního zobrazování. V neživé přírodě, mohou být hyperpolarizovaný plyny využity jako kontrastní látka při studiu mikroporézních materiálů, jako jsou zeolity, stavební látky a hmoty, atd. V této doktorské práci je popsán vývoj a konstrukce aparatury pro hyperpolarizaci xenonu (izotopu 129Xe). Nákup hyperpolarizovaného xenonu od jiných výzkumných center v zahraničí a jeho dovážení by ovšem nebylo efektivní a to zejména z důvodu náročnosti zajištění potřebných fyzikálních podmínek pro přepravu hyperpolarizovaného plynu. Toto bylo hlavní motivací k vývoji vlastní technologie pro přípravu hyperpolarizovaného xenonu. Se zvládnutou technologií by bylo možné navázat spolupráci s medicínskými zařízeními, nebo s týmy zabývající se živou nebo neživou přírodou (např. při studiu mikroporézních materiálů, gelů, v zemědělských aplikacích nebo při výzkumu využívajících zvířat, atd.). Cílem této práce je studium teorie hyperpolarizovaných vzácných plynů se zaměřením na 129Xe a experimentální ověření a změření relaxačních časů pomocí jaderné magnetické rezonance. Vzhledem k tomu, že je možné hyperpolarizované vzácné plyny skladovat pro pozdější využití, se tato práce také zabývá možnostmi zásobníku hyperpolarizovaného vzácného plynu a jeho teoretickým a experimentálním řešením. V této práci jsou popsány především dva základní typy experimentů přípravy hyperpolarizovaného xenonu. V obou jsou využity zatavené válcové skleněné vzorky naplněné xenonem a doplňujícím plynem – dusíkem, heliem. První z experimentů se zabývá měřením vlastností termálně polarizovaného xenonu a druhý měřením vlastností hyperpolarizovaného xenonu. Pro hyperpolarizaci 129Xe bylo použito výkonového laseru a experimentálně byla zkoumána jednak míra polarizace na základě změny spektrální hustoty čerpacího laserového svazku a dále pak optimální doba optického čerpání 129Xe a relaxační časy xenonu.
87

Analýza provozu uzlu sítě po připojení jaderného bloku velkého výkonu / Grid Node Operation after Large Nuclear Unit Connection to the Grid

Prokop, Ondřej January 2016 (has links)
The thesis deals with the analysis of the grid node operation after the connection the nuclear unit. The aim of the master´s thesis is to describe the influence of network´s faults to a nuclear unit. Thesis is dealing with three fundamental problems. An influence of short circuits and power imbalance on the synchronous generator of nuclear power plant and its operation of the island network. The thesis is focused especially on the nuclear unit. However, in the case of any failure in the network, it´s necessary to check other units and their protections in the test system because unit failure could cause the disintegration of the power network. For the purposes of the simulation a test system of the power network has been developed. The test system was optimized in the LUG software, which is used to calculate the power network. Transient simulations are performed in the MODES software. Single faults are configured with scenarios. Results are generated into output files. Analysis of influence network´s faults on the synchronous generator of nuclear power plants. The ability of the synchronous generator to restore the primary steady state or hold the new steady state during changes in operating parameters of the network is one of the important parts of the safe and reliable operation of the power network. During the short circuit the damped transient actions occur. With the extension of the short circuit duration, the amplitude of the transient action increases. The risk of the stability loss of a synchronous generator increases. Therefore, the critical clearing time of a short circuit is being defined, which is the time when there is not any loss of stability. Critical clearing time of research generator is sufficient to turn off the short circuit with the help of its protection (the worst case is 0,8 s). For example, by comparison with the hydroelectric power plant, the critical clearing time is much longer. Models of other power plants have been designed with high reliability so in the case of these faults, it doesn’t cause the disintegration of the power network. Creation of island grid is characterized by strong current surges. Units must be resistant to these surges. In the island grid fast changes of the electrical parameters often occurs. Therefore, units must respond to these changes as quickly as possible and in the broadest limits. For this purpose an island operation regulator is being used. In the case of surplus island grid in steam power plants a dump condenser can be used. This is an important ability of steam power plants because the units are able to react quickly to changes of electrical parameters in island grid. The main result of this thesis is the behavior of the nuclear power plant during various faults in the power network. Researched generator of the nuclear power plant is highly stable against faults in the power network based on the findings. The results allow to continue in this topic with real network and real unit of nuclear power plant.
88

Náhřev a spouštění jaderného bloku Elektrárny Dukovany po odstávce / Warming and Starting Nuclear Unit up of the Dukovany NPP after the Outage

Ludvík, Lubomír January 2016 (has links)
This thesis deals with the analysis of warming and starting up the nuclear unit of Dukovany NPP after the outage. First part explains the various operating modes of nuclear power plants, specifically operating modes of Dukovany NPP. The following part contains the analysis of heat sources in the primary circuit and also the individual production and consumption of steam by the NPP. The next part deals with division into several points of the warming of the Dukovany NPP. The analysis of warming nuclear unit after a outage is made on the basis of the industry based data, measured in December 2015. The result of the analysis is determination the amount of steam passing from a another nuclear unit, which is following by the own proposal of the external steam source.
89

Zděšení či radost na straně sousedů? Typologie reakcí sousedních zemí na první provedené jaderné testy / Dismay or delight on the neighbour's side? The typology of neighbouring countries' reactions to the first nuclear tests conducted

Sasová, Kateřina January 2018 (has links)
This Master thesis compares the reactions of the neighbouring countries to first nuclear tests carried out by their neighbour. It deals with first nuclear tests of eight countries (USA, Soviet Union, United Kingdom, France, China, India, Pakistan and North Korea) and with the reactions of states that are or were at the time of the first nuclear test neighbours of concerned country. In the end, forty-seven reactions of neighbouring countries were examined in this thesis. The author relies to a large extent on qualitative research when she compares individual reactions of the countries and creates eight case studies, each focused on one nuclear state. The main output of this thesis is a clear and well-arranged typology of countries' reactions to the first nuclear test carried out in the state right across their borders. The types of reactions that have been identified in this thesis vary all the way from active support and passive coming to terms with the situations, through neutral reaction all the way to passive disapproval and active rejection. This typology can then in the future contribute to a better predictability of the neighbours' reactions and therefore also to a better assessment of how such event might affect the stability of the region.
90

Vliv odstavení jaderných elektráren na energetickou bezpečnost: komparace Německa a ČR / Impact of nuclear power plants decommissioning: comparison of Germany and the Czech Republic

Myslivcová, Kateřina January 2019 (has links)
The diploma thesis examines the effect of decommissioning of nuclear power plants on the energy security of two European countries - Germany and the Czech Republic. First, the author focuses on theoretical anchoring of energy security. The practical part then examines both countries from the perspective of their energy mixes and policies and infrastructure interconnection. This is the starting point for the comparison of the effects of the decommissioning of nuclear power plants. Second, the author presents three scenarios to replace nuclear energy, exploring how German and Czech energy security will change. The first scenario is the use of renewable energy only. The second option is a combination of renewable energy and coal. Finally, the third option is again a certain proportion of renewable energy along with natural gas. Last but not least, the author concludes in the presented paper that, despite the various possible combinations of how to replace nuclear energy, both countries would be worse off within the framework of energy security.

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