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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.
321

Wireless IO : A wireless accessory for integration of an Axis Communications camera in a sensor network.

Eriksson, Hannes, Brange Sollie, Ivan January 2017 (has links)
When installing new network security cameras in buildings, the cameras are often connected to sensors via signal wires. Since most building already have internet and electricity drawn throughout the structure, the procedure of routing a new signal wire can be costly and time demanding. By replacing this wire with a wireless link, the cost and time it takes for the customer to install a camera could be reduced. The objective for this thesis is to investigate different wireless technologies used in short range, low power wireless communication networks such as PANs and LANs. Focusing on technologies used in the surveillance segment a decision will be made on which wireless technology that would suit as a link between a sensor and a camera for transmitting trigger signals. The technology will then be implemented in a proof-of-concept accessory, which can give an Axis Communications camera wireless functionality through it’s IO port.
322

Décharges Sparks dans les liquides diélectriques : caractérisation et application à la synthèse de nanoparticules

Merciris, Thomas 07 1900 (has links)
Ce projet de recherche s’inscrit dans le parcours international de la maitrise de Physique (option plasma) de l’Université de Montréal en collaboration avec l’Université Paul Sabatier de Toulouse (France). Il concerne la caractérisation des décharges électriques (Sparks) dans les liquides diélectriques et ses applications dans la synthèse de nanoparticules. L’objectif est d’amélioré la connaissance des conditions de formation des nanoparticules. Cela implique de caractériser l’ensemble du système expérimental et de développer sa métrologie d’une part, et d’autre part d’obtenir l’évolution des paramètres plasma lors de la synthèse. Dans un premier temps, sur le site du LAPLACE (UMR5213), Toulouse, il a fallu développer une alimentation électrique impulsionnelle destinée à réaliser des décharges dans les liquides. En se basant sur un dispositif existant qui fût amélioré, le fonctionnement a été caractérisé du point de vue électrique (courant - tension). L’application à la synthèse de nanoparticules a été ensuite abordée pour différentes conditions expérimentales, en considérant l’aspect énergétique (bilan d’énergie, caractéristiques de la décharge…). Les travaux se sont poursuivis à l’Université de Montréal, où un circuit électrique équivalent du système expérimental est réalisé afin de visualiser l’évolution temporelle des paramètres plasma (température et densité électronique) en fonction des paramètres électriques choisis. Aussi, la synthèse de nanoparticules de Co et Ni par la décharge a été évaluée et les nanoparticules formées sont caractérisées à l’aide du microscope électronique à Transmission de Polytechnique Montréal. / This research project is part of the international master's program in Physics (plasma option) between Université de Montréal and Université Paul Sabatier - Toulouse (France). It concerns the synthesis of nanoparticles by pulsed electrical discharges in liquids. The objective is to develop the synthesis process while improving the knowledge of the formation conditions of nanoparticles. This involves characterizing the entire experimental system and developing its metrology on the one hand, and on the other hand obtaining the evolution of plasma parameters during synthesis. Initially, at the LAPLACE lab (UMR5213), Toulouse, it was necessary to develop a pulsed electrical supply to produce discharges in liquids. Based on an existing device that, after being improved, the discharge process is characterized from the electrical point of view (current, voltage). The application of the device in the synthesis of nanoparticles was tested under different experimental conditions, considering the energy aspect (energy balance, characteristics of the discharge, etc.). The second part was conducted at Université de Montréal, where the synthesized nanoparticles are characterized using the transmission electron microscope of Polytechnique Montreal. Also, the electrical circuit equivalent to the experimental system was determined to visualize the time evolution of the plasma parameters (Temperature and Electron Density) based on the electrical characteristics.
323

Utbyte av styrsystem : Projektering, implementering och verifiering / Exchange of PLC control systems : Projection, implementation and authentication

Johansson, Anton, Bigeat, Régis, Kerr, Michael January 2020 (has links)
Sjöfartshögskolan i Kalmar behövde förnya sin programvara för programmerbara styrsystem (PLC), detta ledde till att två styrsystem blev påverkade. Det ena är för att styra och reglera en ångprocess medan den andra används för att styra en simulatortank. Det har tidigare varit relativt svårt för lärare att få studenter att komma igång med programmeringen då det förra systemet var komplext. Linnéuniversitet bestämde sig därför att ett utbyte av styrsystemet för ångprocessen och arbetsstationer var att föredra. Ett viktigt mål var att få arbetsstationerna mindre eftersom antalet stationer kommer utökas. Det framkom under arbetets gång att uppdatering av dokumentation av systemen behövde göras samt en förenkling av växling mellan PLC och regulator. Resultatet är ett system som är kompakt och lättare att hantera. / Kalmar Maritime Academy needed to renew the software for programmable logic controller (PLC). There are two systems that are involved, one is for controlling a steam process and the other a simulation of a cistern. Previously it has been relatively difficult for the teachers to get the students to begin with the programming because the prior system was to complex. Linnaeus University therefore decided that a change of control system for the steam system and workstation was preferable. An important task was to minimize the workstation size because the number of stations are increasing. While performing the work it became apparent that the documentation for the system needed to be updated, and to simplify the switch between PLC and regulator control. The result was a compact and easier system to use.
324

Zákaznicky upravitelný modul zadní skupinové svítilny s HD rozlišením / Customizable rear combination lamp module with HD resolution

Prokš, Jiří January 2017 (has links)
This thesis deals with the design of LED matrix array contains 150 LEDs. In the first part, the thesis identifies source of light like OLED and LED and provide an overview of their lifetime, reliability and basic principle of design systems with LEDs. The thesis then describe design of LED matrix array, deals with power supply of this LED array and with cooling of LED. Finally the thesis describes a software for contol of LED matrix array.
325

Záznamového zařízení pro oblast civilního letectví / Data storage system for area of civil aviation

Kotulič, Dominik January 2018 (has links)
In the thesis the design of the Data Storage System (DSS) is proposed with the respect to the V-Model methodology. The design is based on users requirements, from which the system requirements are created and the technical specification of the DSS is developed. In the technical specifications the functionality of the DMM and HMI DSS subsystems are described and sub-system requirements are assigned to them, then they are subdivided and assigned to individual DMM (Data memory module) and HMI hardware items. Moreover, requirements are analyzed on hardware items, specific electronic components, are selected and implemented into the block design of the DMM hardware. Based on the block design of hardware, the hardware of the DMM subsystem is designed, selectively simulated and implemented along with the printed circuit board. On the implemented hardware of the DMM subsystems measurements are performed in order to verify the basic functionality of the hardware and the calculated, assimilated and measured values are compared as well. At the end of the thesis there is a short description of the implementation of the software design and its use for basic initialization of the selected processor, together with the verification of its basic function - measuring the frequency of the internal clock sources and the clock domains. The work is completed by sending a message of defined parameters to the selected communication line and sapling it by an oscilloscope, so that the basic function of the DMM subsystem is verified.
326

Přenosný číslicově řízený stabilizovaný zdroj symetrického napětí / Portable digitally controlled stabilized source of symmetrical voltage

Hynek, David January 2020 (has links)
This thesis deals with a design of a power supply for a measuring equipment for a geophysical mapping intended to do a reconstruction of an electrical impedance of a ground environment of water reservoirs. The power source is going to be used for laboratory measurements and for outdoor experiments. The thesis describes the selection of suitable components, equipment design and testing. The theoretical part explains the functions of used components and the principle of an electrical impedance tomography. The conclusion summarizes the properties of the proposed solution and evaluates the final product.
327

Vysokonapěťové struktury pro galvanickou iziolaci v integrovaných obvodech / High-Voltage Structures for Galvanic Isolation in Integrated Circuits

Ptáček, Karel January 2020 (has links)
Tato dizertační práce představuje novou techniku laterární rezonanční vazby, která je využita v návrhu galvanicky izolovaného posouvače úrovně, který je následně implementován v 800 V půlmůstkovém kontroléru pro průmyslové aplikace. Ve srovnání s tradičními galvanickými izolátory jsou výrobní náklady tohoto řešení nižší. Pro aplikace vyžadující vyšší úroveň galvanické izolace je popsán následný vývoj galvanicky izolovaného posouvače úrovně, který využívá pouze jeden galvanicky oddělený posouvač úrovní pro komunikaci v obou směrech, což výrazně snižuje plochu struktury izolátoru. Jako součást následného návrhu je představen galvanický izolátor který je schopen přenášet analogovou hodnotu napětí. Analogový izolátor byl testován v reálné aplikaci síťového spínaného zdroje jako náhrada standardního optočlenu. Tato konstrukce umožňuje integraci primárních a sekundárních obvodů v jednom pouzdře, což umožní snížit složitost a cenu spínaného zdroje.
328

Pasivní PFC filtry pro spínané napájecí zdroje / Passive PFC filters for SMPS

Matejov, Michal January 2008 (has links)
This work deals with theory of switched power sources. There is description of the ways for connection and their practice purposes. In the next parts there are defined requirements on input supply circuit for these sources, especially for the form of output current. There are mentioned the basic connecting methods of PFC circuits and these methods modify the output current to meet the requirements of specification ČSN EN 61000- 3- 2. In the next parts there are shown simulations of PFC circuits made by Pspice application. Further is the basic description of sources construction for the sources which were used for testing and measuring. The final part deals with evaluation of the measuring on the chosen computer’s source. It compares between the manufacturer’s solutions and PFC circuit made by ourselves.
329

Výpočet spolehlivostních ukazatelů části distribuční sítě E-ON ČR / The Continuity Indicators Calculation of E-ON ČR Distribution Network Segment

Girga, Eduard January 2010 (has links)
The aim of this master’s thesis is calculation and analysis of reliability indicators of the company E.ON Česká republika, s.r.o. distribution network in the south Moravia territory (area of former Jihomoravská energetika) for the period of one year, from 1st November 2008 to 31st October 2009. We consider events incurred on overhead or underground lines of level of high voltage or directly connected with these lines. Events originated from extensive disaster interruption of electric energy supply caused by particularly unfavourable external effects are not considered, because network components can not be efficiently dimensioned on those influences. Known aspects of the events are time of origin, time duration, place and cause of failure inception. Analysis of reliability indicators is accomplished according to different point of view. The first aspect is the hours of day, during which the event lasted. The second aspect is the hours of day, during which the event incurred. The third one focuses component pointed as reliable for the origin of the event. The last standpoint is percentage load of the line outlet, on which the event occurred. We can ordain this load as the proportion of current flowing through the line outlet in the time of event inception and of the value of maximum current set up on the protection of the line outlet. Indications mentioned in the last sentence were searched in the dispatcher centre thanks to graphical interface of application RIS JME Brno. In the theoretical part of the work there is described the structure of distribution network and its fundamental influence on the continuity of electric energy supply, the ways of evaluation and increasing of electric energy supply reliability, regulation of continuity of electric energy supply with emphasis on regulation in the Czech Republic valid until 26th February 2010 and since 27th February 2010. The last theoretical part focuses on definition of failure and differentiation of failures according to various aspects.
330

Nabíječka autobaterií se spínaným zdrojem / The inverter based battery charger

Kadlec, Josef January 2010 (has links)
The aim of this master’s thesis is provide detailed information about car battery’s charger with a switching power supply. The kind of this power supply is one-pulsed conducting inverter with transformer. The charger’s rates of nominal voltage are 6 and 12 V. The method of charging is charging by constantly voltage with a current limitation. The values of a current limitations are 0.5A, 5A and 20A. The charger’s maximal current is 50A. This current can help to the accumulator with starting of a vehicle. This device is equipped by indicators which indicate the end of charging.

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