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New Conceptions of Power Pulse Converters Using Extremely Fast Switching Semiconductors Based on SiC
Kuzdas, Jan ; Chlebiš,, Petr (referee) ; Drábek,, Pavel (referee) ; Vorel, Pavel (advisor)
This work deals with high power pulse converters (tens of kW) using new semiconductor devices of silicon carbide (SiC). Firstly the current state of the issue is analyzed. A research in a specific area of high power buck converters with pulse transformer follows. There was a strong emphasis on minimizing size and weight. The design process was focused also on reliability and robustness. To achieve the defined objectives, it was necessary to use the latest available switching transistors and diodes, and an unusually high switching frequency (100 kHz at a power of about 16 kW). Due to the high switching frequency, we achieved small size of pulse transformers and output chokes. An optimization of high-frequency pulse transformer with demand on minimum volume and weight of core and windings represents a separate theoretical part of the thesis. There have been proposed several analytical solutions of optimization problems, the results of which could overlap with the implementation in practice of switching power supplies. The combination of high switching frequency, fast semiconductors and the high power brings various parasitic effects to the power circuit. In the thesis, these parasitic effects are analyzed. Solutions which minimize or completely remove those effects were theoretically designed and successfully implemented, tested and finalized in experimental part of the work. Detailed description of the implementation of functional sample and series of validation measurements are included in the final part.
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Evaluation of Selected Software Tools for Modeling the Leakage of Hazardous Substances in Accidents in the Chemical Industry
Hrušková, Veronika ; Martincová, Jana Victoria (referee) ; Adamec, Vladimír (advisor)
The thesis is aimed at the modeling of releases of hazardous substances to the designated software tools. The work consists of three parts. The first part is theoretical, which deals with hazardous substances and their legislation, accidents in industry, physical models of leakage and dispersion of hazardous substances and factors influencing their spread in the air and finally software tools. The second part, experimental, describes some software tools and their subsequent modeling. The third part is devoted to the results of modeling and analysis of selected software tools. The aim of the thesis is to analyze selected software tools for modeling the release of hazardous substances, to compare their explanatory power and potential use.
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Tightness measurement of hermetic compartments in NPP
Sklenár, Ondrej ; Martinec, Jiří (referee) ; Šen, Hugo (advisor)
This diploma thesis deals with measuring the tightness of the hermetic area of nuclear power plant in the way of improving safety. Describes the layout and function of this area - the primary circuit of NPP with WWER 440/213 reactors, as well as methodology for leakage search and leakage calculation procedures. Personal contribution to the issue is a proposal improving tightness of the current state in hermetic area of NPP Jaslovské Bohunice – transition of jacketed pipe designed to collect water from the floor in the box of the steam generator to the heat exchanger of the shower system. This system belongs to the safety system designed to reduce pressure in the LOCA type of accident.
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Experimental verification of flood kidney three bag functionality
Požárová, Miroslava ; Dráb, Aleš (referee) ; Žoužela, Michal (advisor)
This bachelor's thesis deals with the system of large-volume flood bags Protex - K manufactured by the company KOEXPRO OSTRAVA, joint stock company. The bags consist of polyethylene fabric filled with cement and fly ash mixture. The system enables creation of many shape modifications. One of them is the so-called triplet formed from three hose bags with the nominal diameter of 300 mm. The goal of the work was to verify functionality of this bag in one of the hydraulic troughs in the Laboratory of Water Management Research of Department of Water Structures of the Faculty of Civil Engineering, Brno University of Technology. To assess the functionality, the bag stability was tested with various water levels, and discharge coefficient and specific leakage per one standard meter of the bag was determined. The resulting discharge coefficient was compared with discharge coefficients of similarly shaped constructions. The work includes comparison of the flood bags with commonly used bags. Furthermore, the data obtained by measuring and processed in the tabular and graphical form are presented in the work.
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Experimental verification of flood hose bag functionality
Valdová, Klára ; Dráb, Aleš (referee) ; Žoužela, Michal (advisor)
This bachelor's thesis deals with functionality verification of one type of flood protection system. It is a large-volume hose bag Protex-K with the nominal diameter of 680 mm, which is supplied by the company KOEXPO OSTRAVA, joint stock company. The bag is made of polyethylene fabric and filled with cement and fly ash mixture, which is fed into the bag by means of screw pumps. The first part of the work is focused on the classification of flood barriers and their laboratory tests. The bag with the nominal diameter of 680 mm underwent the stability test, its discharge coefficient and specific leakage were determined. The volumic mass of the cement-flyash mixture was determined both in the dry and in the saturated condition. All these tests were performed in the laboratory of Water Management Research of the Faculty of Civil Engineering Brno University of Technology. The work also includes the data obtained by measuring, processed and presented in the tabular and graphical form.
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The design of the small water reservoir
Galuška, Martin ; Hyánková, Eva (referee) ; Doležal, Petr (advisor)
The concept of this work is to assess options of a small water reservoir design on the selected area Bezměrov. Part of the work refers to different types and functions of small dams and their water management solutions. There is a geological survey presented which is describing the composition of the soil layers and investigating available materials for dam constructions. Water balance has been processed for considered dam profiles evaluating specific outflow of the catchment area, vapor and leakage through a simplified design of the dam. That creates a basic conception about possibilities of water manipulation in this area. Based on this evaluation there are several options processed to explore the retention effects of this two small water reservoirs system above Bezmerov locality.
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Design of conception of data loss prevention
Brejla, Tomáš ; Střížová, Vlasta (advisor) ; Sejk, Vratislav (referee)
This work deals with the making of conception of implementation of processes and software tools designed to ensure sensitive data leakage prevention from the organization infrastructure. The structure consists of three key parts. The first one describes theoretical basis of the work. It explains what is the data loss prevention, what it comes from, why it is necessary to deal with it and what its goals are. It also describes how this fits into the whole area of corporate ICT security environment. There are defined all the risks associated with leakage of sensitive data and there are also defined possible solutions and problems that are associated with these solutions. The first part also analyzes the current state of data loss prevention in organizations. They are divided according to their size and for each group there is a list of the most common weaknesses and risks. It is evaluated how the organizations currently solve prevention of data loss and how they cover this issue from both a procedural point of view and in terms of software tools. The second part focuses directly on the software tools. It is characterized the principle of operation of these systems and it is explained their network architecture. There are described and evaluated current trends in the development of the data loss prevention tools and it is outlined possible further development. They are divided into different categories depending on what features they offer and how these categories cover the needs of organizations. At the end of the second part there are compared the software solutions from leading vendors in the market against actual experience, focusing on their strengths and weaknesses. The third part presents the core content. IT joins two previous sections and the result is the creation of the overall concept of the implementation of data loss prevention with focus on breakdown by several different levels -- processes, time and size of the company. At the beginning of this third section it is described what precedes the implementation of data loss prevention, and what the organizations should be careful of. It is defined by how and what the organizations should set their own expectations for the project could be manageable. The main point is the creation of a procedure of data loss prevention implementation by creating a strategy, choice of solutions, to the implementation of this solution and related processes. The end of the third part deals with the legal and personnel issues which are with the implementation of DLP very closely related. There are made recommendations based on analysis of the law standards and these recommendations are added to the framework approach of HR staff. At the very end there are named benefits of implementing data loss prevention, and the created concept is summarized as a list of best practices.
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