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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.
171

Regulovatelný zdroj pro napájení LED / Controllable power supply for LED lighting

Morávek, Petr January 2018 (has links)
This thesis deals with the description of artificial light sources, that use light-emitting diodes for their operation. Further down, the parameters of LEDs and their emissions are detailed. The work follows with the characterization of principles of LED power regulation. In the practical section, an example of one of the possible LED light source topologies, is designed. The offered solution includes the options to manually and automatically regulate the chromaticity of emitted light. Functionality of the solution was verified experimentally.
172

DC-DC měnič pro systém maticového řízení pro LED / DC-DC converter for matrix controller system for LED

Gociek, Krzysztof January 2019 (has links)
This diploma thesis deals with design and subsequent realization of DC / DC converter for supply of matrix LED fields for the automotive industry. Such a converter must be able to supply a current of several Amperes and a voltage of the order of tens of Volts. Matrix headlights are currently being developed by a number of automotive companies. These headlamps allow independently to control the intensity of light incident on different objects or people who are in front of a car. In addition to the front headlamps the matrix LED lights are also used in the rear and signaling lights. Here it serves mainly to create different animations that have no function except the overall enhancement appearance of the vehicle. All of these lights need power units that will be suitable to regulate current flowing into various combinations of LEDs illuminated.
173

Řídicí obvody s vysokou účinností pro LED / High efficiency control circuits for LEDs

Havlík, Vojtěch January 2020 (has links)
The aim of this diploma thesis is to design two different switching power supply circuits with integrated circuits suitable for controlling of LED. The theoretical part describes the principles of two main switching converters topologies – buck and boost. Furthermore, a universal H-bridge structure of switching supply is described. This is compared with the typical switching supply design. Based on specified requirements, two circuits are designed with selected IO which are suitable for using in the automotive industry. Their function and typical schema are described. In the practical part is realized design with both selected IC, choosing components and layout PCB. Set of tests are carried out with manufactured samples. Based on measured results are performed optimalization of samples, which are tested also. In the end of this thesis both samples are compared in terms of function, efficiency and EMC.
174

Powerline komunikace pro řízení LED světel / PowerLine Communication for LED unit control

Šebesta, Ondřej January 2020 (has links)
This diploma thesis deals with the design and testing of a system for powerline communication, enabling control of LED lights. The work first describes the basic principles of powerline communication, specifies the communication bands and summarizes the basic functional requirements for communication within the system for LED lighting control. It also describes the method of selecting a modem for powerline communication, the design of a test module with this modem and also the method of testing real communication between two test modules, including test results. The most comprehensive part of the work describes the design of hardware and software of the universal PLC module and how to use it. In addition, it referes to the development tools used as an example of implementation in LED lighting. At the end of the work are summarized the results of testing the proposed system.
175

Elektronický světlík / Electronic skylight

Coufal, Martin January 2021 (has links)
Theoretical part of this thesis describes LEDs and other circuitry used for LED light design. LED light is designed, manufactured and put into operation. This thesis examines possibilities of measuring exterior light and its key parameters. The device uses two sets of LEDs – warm white and cold white to create light with parameters dependent on exterior light. LEDs are driven by constant current sources that are designed, manufactured and examined in this thesis. The device is microprocessor-controlled, which allows to switch between multiple modes of operation. Flyback SMPS is used to power the microcontroller.
176

Zařízení pro měření a zobrazování sportovních výsledků / Device for sports results measuring and displaying

Frelich, Marek January 2013 (has links)
This project is dealing with a design of device for measuring and displaying of sports results. The project is divided into three parts - the design of control board for LED display, next the control unit and finally the remote control. LED display contains LED segments and graphical line for the text. The control unit and remote control are communicating with LED display, measuring devices or with a PC. It is possible to operate the whole system by tablet or a smartphone. There is a software made for all processors of all parts, which can demonstrate the function of the system and all added peripherals.
177

Úprava křižovatky I/50 x III/3836 u Velešovic / Modifying the intersection of I/50 x III/3836 Velešovice

Sýkora, Martin January 2012 (has links)
My thesis is about intersection which is very dangerous, because there is´t lighting so intersection is unclear and drivers don´t to abide speed limit. There are serious accidents so I had to modify it. I designed three versions: First with concrete barriers, second is in trims and last one is spiral roundabout. Last version is more refined. Every version is with LED lighting in all area.
178

Osvětlovací soustava pro konfokální mikroskop s duálním rastrováním / Illuminating system for a tandem-scanning confocal microscope

Slabý, Tomáš January 2008 (has links)
The diploma thesis deals with a design of illuminating system for tandem-scanning confocal microscope using a high-power LEDs.
179

CIRKULACE / CIRCULATION

Bartošová, Zuzana January 2017 (has links)
The diploma project Circulation tries to solve the problem of repeating cycles. It is an object with organic shape, created from a tube with light circulation on it. This object is based on idea of human constantly repeating actions and processes, whether they refer to the human body and mind, nature or society. The object is created site-specifically in to the gallery (Brno Gallery OFF/FORMAT) and tries to fill the space. The line passing through the gallery space can be seen as a route or path, but it can also remind a movement without a clear goal, or go around in circles. The omnipresent cycle, is then an individual contribution to the whole and it can be presented as a irregular curve full of dramatic twists and turns, ups and downs. The light (made by digital LED strip), which constantly copies the organic shape of the tube, represents an endless flow of information. The object tries to point out the never ending circulations in our lives; the object does not solve the problem, it is rather a statement.
180

Recherche de solutions optimales pour les LED et OLED utilisées en environnement automobile / Technological solutions for LED and OLED used in automotive applications

Thin, Guillaume 13 January 2016 (has links)
Le succès de l’introduction des composants optoélectroniques dans le domaine automobile s’explique par certaines caractéristiques qu’offrent les LED. En effet, ces nouvelles sources lumineuses permettent de réduire la consommation électrique des véhicules tout en offrant une longévité bien supérieure aux sources lumineuses traditionnelles. De plus, leur encombrement réduit élargit considérablement les possibilités de style des optiques des véhicules et leur caractère électronique permet d’imaginer de nombreuses applications nouvelles.Malgré leurs performances, les LED sont à l’origine d’une part importante des problématiques de fiabilité électronique constatées et probablement futures. Il est donc nécessaire, pour les équipementiers automobile, de trouver les solutions technologiques améliorant les performances et la robustesse des LED dans leurs applications et de développer les outils permettant de maîtriser les risques liés à ces évolutions technologiques.Nous identifions dans ce manuscrit les enjeux concrets de fiabilité en soulignant l’importance de l’étude de la robustesse des LED et le moindre intérêt de l’étude de leur longévité dans le cas du domaine automobile. Nous décrivons les outils et méthodes permettant de caractériser les paramètres thermiques, optiques et électriques de ces composants. Notamment nous proposons une méthode de mesure de la température de jonction. Puis, nous exposons les résultats des caractérisations des LED employées dans des applications pulsées et proposons des solutions technologiques permettant d’améliorer leur performances et leur robustesse dans ces conditions d’utilisation. Par ailleurs, le développement d’un banc de test est décrit et les résultats obtenus à l’aide de ce dernier sont analysés. Enfin, nous proposons une méthodologie de caractérisation et d’évaluation de la fiabilité des composants OLED pour les applications automobiles / The large introduction of optoelectronics technologies in automotive applications is related to the high performances offered by LEDs. Indeed, these new light sources allow cutting down the electrical consumption and ensuring long lasting of lighting functions. Besides, their reduced size and their electronics behavior enable new styling and operating functions. Yet, reliability remains a great concern in automotive applications.We identify in this manuscript the real reliability stakes and emphasize the highest importance of robustness versus lifetime of LED for automotive applications. We then describe the methods and tools necessary to characterize the thermal, electrical and optical parameters of these components. In particular we propose a new method for junction temperature estimation. Characterizations results for LEDs used in pulsed applications are given and solutions are proposed to improve their robustness and performances under such conditions. Moreover, the development of a test bench is presented and results obtained are discussed. Finally, we propose a methodology of characterization and evaluation of the reliability of OLED used in automotive applications

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