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Degradation of liquid insulators for high voltage
Komárek, Filip ; Štěpánek, Jaroslav (referee) ; Krbal, Michal (advisor)
This bachelor's thesis deals with measurement of liquid insulators. Mainly it deals with diagnostic tests of transformer oil. Diagnostic tests are needed to identify oil status and to determine the parameters of the oil. The status of the used oil determines its type of degradation and progress of degradation. For the determination of degradation it is necessary to know the composition of the essential oil, to determine how it has changed the structure of the oil and the oil did not contain before use. To determine the basic electrical properties of the oil are used in diagnostic tests such as dielectric strength and dissipation factor. This work is in addition to a summary of diagnostic tests observation of mineral oil with an unknown degree of degradation and behavior of impurities in mineral oil once the electric field.
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Design of lighting system in high school
Borůvka, Jan ; Štěpánek, Jaroslav (referee) ; Škoda, Jan (advisor)
The theoretical part is focused on lights, notions and calculations in the area of light technology, basic lightning sources and lamps. This work is also about the principle of lightning measuring. The main aim of the work is design of a new artificial lightning system in a High school agriculture in Prerov. At first, the control measuring of existing lightning was done which is mentioned in this work. From the results of control measuring is clear, that existing lighting system in classroom does not suit requirements, which are mentioned in the valid technical norm. Design of a new lightning system meets the requirements in all of the rooms in the building of school. Design of lightning system was done in two variants. The first variant uses lamps with fluorescent tube light sources. The second variant uses lamps with LED light sources. Also is here evaluated financial difficulty of possible installation and comparation of each variants with respect energetic difficulty.
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Influence of temperature on light-technical parameters of LED
Sláma, Pavel ; Štěpánek, Jaroslav (referee) ; Pavelka, Tomáš (advisor)
This thesis deals with LEDs and how temperature influences their parameters. In the first part it is analyzed how semiconductors and semiconductor junctions work, which is fundamental for understanding mechanisms of diodes. Next up is description of electroluminescence and basic description of physical principles, on which it works. Following part is supposed to introduce reader to electro-technical parameters and powering possibilities of LEDs. Following chapter focuses on description of lightning-technical parameters. It aims to describe their meaning and their relation to LEDs. Next part is about influence of temperature. Firstly, it names the parameters which are altered by temperature change. Follows the description of thermal management and its influence on right behavior of LED diodes. The last part contains construction of measuring workplace for analyzing temperature influence on lightning-technical parameters of LEDs. Measurement of chosen electrical and lightning parameters follows up.
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Design of lighting system in car service
Borůvka, Jan ; Štěpánek, Jaroslav (referee) ; Škoda, Jan (advisor)
The theoretical part is focused on lights, notions and calculations in the area of light technology, basic lightning sources and lamps. This work is also about the principle of lightning measuring. The main aim of the work is design of a new artificial lightning system in a workshop which is located in village called Petrov. At first, the control measuring of existing lightning was done which is mentioned in this work.
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Economic comparison of light sources
Růžička, Josef ; Motyčka, Martin (referee) ; Štěpánek, Jaroslav (advisor)
This bachelor thesis deals with the economic comparison of light sources. On the market there is currently no physical quantity that would enable the light sources to be compared from an economic point of view in long-term perspective. The main objective of the work is, therefore, by calculations of the specified (or directly measured) parameters of the light source to provide a uniform total cost of lighting, thanks to which it will then be possible to sort the sources according to the price benefit. Evaluation is based on measurements of 28 light sources from different groups: the classical bulbs, halogen bulbs, compact fluorescent bulbs, compact LED retrofits and dimmable LED retrofits with color-changeable modes. These light sources are meant to be used for indoor home lighting, offices, halls, etc. The final part of the paper clarifies what kind of light sources and for what reasons they are the most profitable and have the greatest potential for the future. There's also a comparison of theoretical parameters provided by the manufacturer, and parameters directly measured in the laboratory and the evaluation of the deviations between them. The use of this thesis comes from provision of the calculation structure to a user who will better understand the topic of costs while purchasing the light source. Well arranged description and information about the light sources in theoretical part of the thesis is another utility to be mentioned.
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Proposal of the village public lighting
Schittenhelm, Dominik ; Baxant, Petr (referee) ; Štěpánek, Jaroslav (advisor)
The thesis is divided into several parts. The first part is theoretical and its main focus is the description of public lighting and the theory regarding lighting technology. The second part continues with the research of the current state in Bezděkov village. The thesis further describes the proposal for the village public lighting with the use of HPS and LED technology, where village models are made for both options to show the requested result. The last part of the work deals with cables dimensioning, the selection of the most effective regulations for lighting, and finally the economic assessment of both projects, while both the investment expenses and the public lighting service fees for the next 20 years are included.
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Thermal Properties of Automotive Light Sources
Halbich, Adam ; Štěpánek, Jaroslav (referee) ; Baxant, Petr (advisor)
The goal of this thesis was to process theoretical basis required for better understanding the matters of thermal simulations, to perform particular simulation and its debugging according to the measurement on actual sample. Theoretical part focuses on the variety of the automotive light sources, then kinds of heat transfer, thermal simulations and possibilities of measurement and results verifying. Practical approach was consisted of reverse engineering of particular light source and building its 3D model. In consequence, the characterization of the material properties was made. At the end the thermal simulation of designed 3D model was performed and the optimalization according to realized measurement was implemented.
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Voltage tests under wet condition
Vondrák, Michal ; Štěpánek, Jaroslav (referee) ; Krbal, Michal (advisor)
The main objective of presented thesis is to design a shower system in order to extend voltage tests by voltage wet testing. The introduction focuses on important aspects related to voltage wet testing. Such aspects originates mainly from Czech but also foreign standards. Following part of the thesis deals with specific wet testing design proposals, which fulfil the standards requirements. The final part of presented thesis is focused on partial experiments. Namely the analysis of rain water properties, behavior of rain drops exiting the nozzle with varying flow and nozzle angle, wet test on insulator in dry and wet conditions.
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Illumination with respect to biological functions
Němec, Jiří ; Štěpánek, Jaroslav (referee) ; Baxant, Petr (advisor)
The paper summarizes the basic light-technical parameters, the principles of visual and non-visual photoreceptions and the effects of light on the organism. Several chapters focus on the mechanism by which light affects hormone levels and the circadian rhytm of the organism. In relation to the lighting system, the impact of electromagnetic radiation, associated with the controls, on the body is also considered. Briefly described are systems based on smart LED light sources or smart switches. The result of the thesis is to choose the solution that best suits the requirements of the contracting authority.
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Measurement of photometric parameters of light sources for interactive panel
Vágner, Richard ; Štěpánek, Jaroslav (referee) ; Škoda, Jan (advisor)
This bachelor thesis deals with measurment of various photometric parameters of light sources designated for interactive board located in the Laboratory of Light VUT FEKT. There is described procedure and processing of photometric and electrical parameters of light sources (incandescent light bulbs, halogen lamps, compact fluorescent lamps, fluorescent tubes and LED lamps). Also there is presented processing method of designing cards that will contain mentioned parameters.
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