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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.
291

Digital Timing Generator for Control of Plasma Discharges

Liao, Hao Hsiang January 2019 (has links)
This thesis report presents a new design of a synchronization unit for high power impulse magnetron sputtering (HiPIMS) applications used for depositing thin films. The proposed system is composed of two major hardware parts: a microcontroller unit (MCU) and a field-programmable gate array (FPGA). The control range of the new system is increased by at least ten times compared to existing synchronization unit designed by Ionautics AB.In order to verify the system and benchmark its innovations, several batches of the thin film have been deposited using the new technology. It is shown that HiPIMS with synchronized pulsed substrate bias can effectively improve coating performance. Pulsed substrate bias with user-defined pulse width and delay time is possible to use in the new control mode proposed by this master thesis work; Bias mode. As a result, this master thesis work enables users to flexibly control the HiPIMS processes.
292

Traçabilité sécurisée embarquée : authentification autonome d'objets et de systèmes embarqués / Embedded and secure traceability : autonomous authentication of objects and of embedded systems

Idrissa, Abdourhamane 20 September 2012 (has links)
L'authentification homme-machine est une problématique largement développée pour les télécommunications. Une authentification dans le sens "machine-homme" permettra d'assurer l'utilisateur humain assermenté du fonctionnement intègre d'une machine lors, par exemple, d'une session de vote électronique ou d'une vérification d'objet en traçabilité sécurisée. Cette thèse se focalise sur la traçabilité sécurisée sans accès (systématique) à un canal de communication. Nous décrivons différentes techniques d'authentification de produits manufacturés en nous concentrant sur une méthode de caractérisation de motifs imprimés. Pour effectivement authentifier un objet, nous montrons qu'un agent vérifieur doit s'assurer de l'intégrité du tiers et du système électronique utilisée pour la vérification. Cependant l'authenticité du système électronique lui-même reste à vérifier. La question que nous adressons alors est la suivante : comment un être humain peut-il se convaincre de l'intégrité et de l'authenticité d'un système embarqué dans un mode hors ligne ? Nous définissons deux familles de solutions. Dans la première, l'utilisateur fait appel, pour les calculs, à un dispositif auxiliaire tandis que dans la seconde l'utilisateur ne fait usage que d'un papier et d'un crayon. Pour chacune des deux familles, nous proposons un protocole d'authentification d'un système embarqué dont la puce, typiquement un FPGA ou un microcontrôleur, dépend de la configuration ou de la programmation d'une mémoire RAM / "Human-to-Machine" authentication is widely developed for modern telecommunications. A "Machine-to-Human" authentication will ensure the trusted human user about the integrity of the machine, for example during an electronic voting session or object verification in secure traceability. This work is focused on secure traceability without any systematic access to a communication network. We depict different technics for goods authentication and we focus on a method based on the characterization of printed patterns. To completely authenticate an object, we show that a human verifier has to be confident in the integrity of the third party and the electronic system involved in the verification phase. However, the authenticity of the electronic system itself has also to be verified. We address here the following question : how a human being can convince himself about the integrity and the authenticity of an embedded system in an off-line environment ? We propose two groups of solutions. In the first one, an auxiliary electronic device is used to perform computing operations. In the second one, the human capability (memory and computational abilities) is exploited. In each group, we propose a protocol to authenticate embedded systems for which the chip (typically an FPGA (Field Programmable Gate Array) or a microcontroller) is initialized according to the configuration or programming of its RAM memory
293

DESIGN AND DEVELOPMENT OF AN EMBEDDED DC MOTOR CONTROLLER USING A PID ALGORITHM / Kontrol av DC-Motor i enbyggda system med hjlp av PID & PWM

Jones, Omar January 2010 (has links)
<p>This project was held at London South Bank University in the UK, with corporation with staff from Linköping University in Sweden as Bachelor thesis.</p><p>This report will guide you through the used techniques in order to achieve a successful cooler/Fan project with a minimum budget and good energy saving methods.</p><p>The steps of setting the used software and components are supported with figures and diagrams. You will find full explanation of the used components and mathematics, in additional to a complete working code.</p>
294

Techniques for low-cost spectrum analysis on quadrature demodulation architectures

Fredlund, Brendon Jeremy 08 July 2010
The Decimator, an SED Systems Ltd. product, is a PCI slot card that performs both time and frequency domain measurements of given input signals. It is essentially a more economical version of a bench spectrum analyzer or oscilloscope, with a PC interface. Several issues limit the speed and accuracy of the results of the Decimator, and the study of these issues is the focus of this thesis. These issues, including but not limited to, are as follows: 1) Imbalances between the received In-phase and Quadrature-phase channels; 2) The FFT and Windowing functions are performed by a microcontroller, but it is desired that they be migrated to an FPGA. While solutions to improve the first issue is being implemented and verified, the second issue is not one of simply reducing a source of error. The second issue requires a cost-benefit analysis on the migration of these signal processing algorithms from an ARM microcontroller to a Xilinx FPGA.
295

DESIGN AND DEVELOPMENT OF AN EMBEDDED DC MOTOR CONTROLLER USING A PID ALGORITHM / Kontrol av DC-Motor i enbyggda system med hjlp av PID &amp; PWM

Jones, Omar January 2010 (has links)
This project was held at London South Bank University in the UK, with corporation with staff from Linköping University in Sweden as Bachelor thesis. This report will guide you through the used techniques in order to achieve a successful cooler/Fan project with a minimum budget and good energy saving methods. The steps of setting the used software and components are supported with figures and diagrams. You will find full explanation of the used components and mathematics, in additional to a complete working code.
296

Techniques for low-cost spectrum analysis on quadrature demodulation architectures

Fredlund, Brendon Jeremy 08 July 2010 (has links)
The Decimator, an SED Systems Ltd. product, is a PCI slot card that performs both time and frequency domain measurements of given input signals. It is essentially a more economical version of a bench spectrum analyzer or oscilloscope, with a PC interface. Several issues limit the speed and accuracy of the results of the Decimator, and the study of these issues is the focus of this thesis. These issues, including but not limited to, are as follows: 1) Imbalances between the received In-phase and Quadrature-phase channels; 2) The FFT and Windowing functions are performed by a microcontroller, but it is desired that they be migrated to an FPGA. While solutions to improve the first issue is being implemented and verified, the second issue is not one of simply reducing a source of error. The second issue requires a cost-benefit analysis on the migration of these signal processing algorithms from an ARM microcontroller to a Xilinx FPGA.
297

Patalpų apsaugos sistemos kūrimas Arduino mikrokontroleriu / Development of the Premises Security System Using Arduino Microcontroler

Motuzas, Armandas 16 July 2014 (has links)
Darbe buvo susipažinta su apsaugos sistemomis, Arduino platforma ir Android sistema. Projektuojant standartinę apsaugos sistemą su Arduino mikrokontroleriu, buvo pasirinktos tinkamiausios dalys. Rasti ir išanalizuoti galimi komunikavimo būdai tarp Arduino platformos ir Android operacinės sistemos. Pasirinktu geriausiu komunikavimo būdu, buvo realizuota standartinė apsaugos sistema, kurią galima valdyti nuotoliniu būdu internetiniu puslapiu arba Android programėle. / In this Project were been familiarized with security systems, Arduino platform and Android system. Designing a standart security system with Arduino microcontroller was choosen the most suitable components. Was choosed and analized possible ways to communicate between the Arduino platform and the Android operating system. Choosen best way of comunication, has been realized in standart security system that can be operated by remote with web page or Android application.
298

Pedalkraft system : Stödsystem för elproduktion i småskalighet

Amaya, Jorge January 2013 (has links)
Detta examensarbete vänder sig till personer som är intresserade att använda nya miljövänligametoderna för elproduktion eller personer som redan använder små vindkraftverk ochsolpaneler med behovet av en extra energikälla i små stugor eller avlägsna platser där tillgångentill elnät är omöjligt. Syften i detta arbete är först och främst att bygga ett system förelproduktion med hjälp av en cykel. Sedan bestämma mängden av elektrisk energi en personkan alstra med systemet. Slutligen svara om detta system skulle kunna använda som ettstödsystem för elproduktion i småskalighet. Den första målsättningen är att utforma ett system med användning av kraftelektronik där denkraften som genereras matar lasterna. Den mekaniska delen kommer att konstrueras som en delav energikällan, därefter kommer det att utformas en kontroll för att styra effekten viaelektroniska komponenter, de elektriska belastningarna matas av systemet, kommer attsimuleras. För att veta den alstrade effekten till styrkrets kommer det att installeras en mätareoch en seriekommunikationsenhet för kommunikation med en dator. Det utfördes en forskning av andra system och produkter i svenska marknaden, för att svara omdetta system kan vara en reserv system för elproduktion i småskalighet. Uppförandet av ett pedalkraftssystem uppnås med användning av en tolv volt likströmsmotormed permanent magnet som energikälla. System har förmåga att visa i en LCD-skärm och sändagenom serieportarna, värde av den alstrade effekten. System kan vägleda denna effekt tillbelastningarna med hjälp av en mikrokontroll. Effekt som genereras i systemet visades att detär signifikant för att beaktas som en ytterligare energikälla, fristående eller integrerad till andra system. / This thesis is aimed at people who are interested in using the new environmentally friendlymethods of electricity generation or people who already use small wind turbines and solarpanels with the need for an additional energy source in small cabins or remote locations whereaccess to electricity networks is impossible. Aims of this work is first to build a system forgenerating electricity using a bicycle. Second is determining the amount of electrical energy aperson can generate with the system. Finally answer if this system could be used as a supportsystem for electricity generation in small scale. The first objective is to design a system using power control where the power generatedsupplied the loads. The mechanical part will be constructed as part of the energy source, thenwill be designed a control for controlling the power via electronic components, electrical loadssupplied by the system, will be simulated. To know the generated power to the control circuitwill install a meter and a serial communication device for communicating with a computer. It carries out a research on other systems and products in the Swedish market, to answer whetherthis system can be a backup system for electricity generation in small scale. The construction of a pedaling power system is achieved using a twelve volt direct currentmotor with permanent magnet as an energy source. System has the ability to show in an LCDdisplay and transmit through the serial ports, the value of the generated power. System canguide the power to the loads by using a microcontroller. Power generated by the system showedthat it is significant to be considered as an additional energy source, stand-alone or integratedwith other systems.
299

Implementação Eletrônica de Sistemas Fuzzy. / Electronic Implementation of Fuzzy Systems.

André Luís Jorge Garcia 06 August 2009 (has links)
Este trabalho investiga a implementação de sistemas fuzzy com circuitos eletrônicos. Tais sistemas têm demonstrado sua capacidade de resolver diversos tipos de problemas em várias aplicações de engenharia, em especial nas relacionadas com controle de processos. Para processos mais complexos, o raciocínio aproximado da lógica fuzzy fornece uma maneira de compreender o comportamento do sistema, permitindo a interpolação aproximada entre situações observadas de entrada e saída. A implementação de um sistema fuzzy pode ser baseada em hardware, em software ou em ambos. Tipicamente, as implementações em software utilizam ambientes de programação integrados com simulação, de modo a facilitar o trabalho do projetista. As implementações em hardware, tradicionais ou evolutivas, podem ser analógicas ou digitais e viabilizam sistemas de maior desempenho. Este trabalho tem por objetivo pesquisar a implementação eletrônica de sistemas fuzzy, a fim de viabilizar a criação de sistemas reais capazes de realizar o mapeamento de entrada e saída adequado. O foco é a utilização de uma plataforma com uma arquitetura analógico-digital baseada em uma tabela de mapeamento armazenada em uma memória de alta capacidade. Memórias do tipo SD (Secure Digital) foram estudadas e utilizadas na construção do protótipo eletrônico da plataforma. Também foram desenvolvidos estudos sobre a quantização, especificamente sobre a possibilidade de redução do número de bits. Com a implementação realizada é possível desenvolver um sistema fuzzy num ambiente simulado (Matlab), configurar a plataforma e executar o sistema fuzzy diretamente na plataforma eletrônica. Os testes com o protótipo construído comprovaram seu bom funcionamento. / This work investigates the implementation of fuzzy systems using electronic currents. Such systems have been used before to solve several of problems of engineering applications, mainly involving process control applications. On more complex applications, the approximate reasoning of the fuzzy logic allows a way to understand the system behavior, allowing approximate interpolation among observed sets of input and output points. The implementation of a fuzzy system can be based in hardware, software or both. Typically, the software implementation uses a programming environment integrated with simulation, helping the designing work. The hardware implementations, traditional or evolutionary, can be analog or digital, mainly for high performance systems. This work aims to research an electronic implementation of a fuzzy system, capable to accomplish an adequate input to output mapping. The focus of this work is to design a platform with an analog-digital architecture based in a mapping table stored in a high capacity memory. Memories of the SD (Secure Digital) type were studied and used in the construction of a prototype of the electronic platform. Also studies were developed on the quantization, specifically to allow the reduction of the number of bits. With the accomplished implementation, it is possible to develop a fuzzy system in a simulated environment (Matlab), to configure the platform and to execute the fuzzy system directly in the electronic platform. The tests with the prototype was successful.
300

Desenvolvimento e implementação de um sistema de controle de posição e velocidade de uma esteira transportadora usando inversor de frequência e microcontrolador /

Raniel, Thiago. January 2011 (has links)
Orientador: Jozué Vieira Filho / Banca: Carlos Antonio Alves / Banca: Tony Inácio da Silva / Resumo: A automação de esteiras rolantes é algo comum e importante em sistemas industriais, mas problemas práticos ainda representam desafios. Um dos desses desafios é manter a precisão em sistemas que exigem paradas sistemáticas, pois folgas mecânicas tendem a provocar variações nas posições de paradas ao longo do tempo. A aplicação de motores de indução têm se tornado comum e soluções eficientes e de baixo custo têm sido pesquisadas. Neste trabalho foi desenvolvido e implementado um sistema de controle de posição e velocidade aplicado em esteiras transportadoras utilizando inversor de frequência, microcontrolador, encoder óptico incremental e sensor indutivo. O movimento da esteira transportadora é efetuado por um motor de indução trifásico, que é acionado pelo conjunto microcontrolador - inversor de frequência. Este conjunto impõe uma frequência no estator do motor através de uma troca de mensagens entre microcontrolador e inversor de frequência (Sistema Mestre-Escravo). Para o envio e recebimento das mensagens, utilizou-se o protocolo de comunicação serial USS® (Universal Serial Interface Protocol) através do padrão RS-485. Os controles de posição e velocidade de rotação do eixo do motor fundamentam-se no sinal gerado pelo encoder óptico incremental, responsável por informar a posição do eixo do motor ao longo da trajetória, e no sensor indutivo que determina uma referência externa importante para a esteira transportadora. Para o funcionamento automático da esteira, elaborou-se um software em linguagem de programação C. Como resultado obteve-se um sistema de controle de posição e velocidade do eixo do motor de indução trifásico que apresenta bons resultados / Abstract: Automated conveyors system have been largely used in industrial applications. However, there are still practical issues to be overcome. One of them is due to the system mechanical limitation which can lead to low accuracy for applications based on "stop-and-go" movements. Induction motors have been largely used in such applications and low costs solutions have been searched. In this work it was developed and implemented a system of positioning and velocity control applied to conveyors which is based on frequency inverter, microcontroller, optical incremental encoder and inductive sensor. The conveyor's movement is made by means of a three-phase induction motor, which is driven by the couple microcontroller-frequency inverter. There are messages exchange between the microcontroller and the frequency inverter (Master - Slave configuration) which is based on the communication serial protocol USS through the RS-485 standard. The position and velocity of the motor spindle are controlled using an optical incremental encoder, which is responsible to provide the position of the trajectory, and an inductive sensor which determines the initial reference to the conveyor. The software used to control the system was developed in C language. The results show a low cost system with good results / Mestre

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