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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.
391

Σχεδίαση και κατασκευή ηλεκτρονικών κυκλωμάτων και συστημάτων

Προδρομάκης, Αντώνιος, Καλουδιώτης, Ευάγγελος 24 October 2012 (has links)
Στην παρούσα διπλωματική εργασία, σχεδιάζονται και υλοποιούνται συστήματα με βάση τη πλατφόρμα του Arduino. Το πρώτο σύστημα αφορά ένα Wireless Persistence of Vision Display, ουσιαστικά μία οθόνη, σχήματος δίσκου, που αποτελείται από μία περιστρεφόμενη στήλη LEDs. Συνεχίζουμε με το σχεδιασμό ενός συστήματος ικανού για γρήγορη πρόβλεψη και ανακατασκευή σημάτων, με σκοπό τη μελλοντική χρήση του στο συγχρονισμό ενεργειακών δικτύων. Ύστερα προχωράμε στην υλοποίηση ενός συστήματος εντοπισμού διεύθυνσης πηγής ήχου, μέσα από την ψηφιακή επεξεργασία ηχητικών σημάτων. Τέλος, η εμπειρία που αποκομίσθηκε με βάση το Arduino μας οδήγησε στη μελέτη μιας εκπαιδευτικής πλατφόρμας βασισμένη σε FPGA, το «F-Penguino», που ως στόχο έχει να αναδείξει την ευελιξία και ταχύτητα συστημάτων βασισμένα σε υλοποίηση με περιγραφή υλικού / In this thesis, we design and implement various systems based on the Arduino platform. The first system is a Wireless Persistence of Vision Display, which is actually a round screen, made of a rotating column of LEDs. We also design a system capable of fast prediction and reconstruction of signals, with an utter goal, its future use in effectively connecting different power networks. Furthermore, we implement a sound source localization system, using DSP techniques and fundamental robotics. Finally, the experience obtained using the Arduino, led us to involve with an FPGA based platform, the “F-Penguino”, the goal of which is to indicate the versatility and speed of systems based on hardware-description implementations.
392

Gerenciamento de memória através da utilização de tabelas de dispersão em um módulo híbrido com suporte ao protocolo CAN (Controller Area NetWork) e ao padrão 802.15.4 ZigBee /

Estremote, Marcos Antonio January 2017 (has links)
Orientador: Nobuo Oki / Resumo: A utilização de redes de comunicação sem fio deixou de ser uma ferramenta opcional para tornar-se uma necessidade no monitoramento de residências, automóveis, controles de processos automatizados e comunicação entre as pessoas. Tratando-se de redes de transdutores cabeadas, as redes CAN (Controller Area Network) são utilizadas em automóveis modernos, instrumentação médica, em veículos táticos, na automação de processos, no transporte metropolitano e em sistemas de controle de fábricas. A maioria das estruturas críticas de sistemas de controle fazem uso do CAN em algum ponto na rede, para conectar sensores que se encontram distantes e controlar atuadores de um sistema, ou para conectar vários controladores que utilizam uma interface em comum. O padrão sem fio, IEEE 802.15.4, comercialmente conhecido como “ZigBee”, foi projetado para operar em baixas taxas de dados, com segurança e facilidade de configurações de rede. Esta tese tem como objetivo desenvolver um sistema heterogêneo utilizando microcontroladores ATMEGA em que, o modelo do protocolo CAN e o padrão IEEE 802.15.4 estejam acoplados. Este módulo será capaz de gerenciar e monitorar sensores e atuadores utilizando CAN e, através do padrão sem fio 802.15.4, comunicar-se com os outros módulos da rede. O interfaceamento entre os pacotes da rede de controle de área (CAN) com a rede ZigBee é realizado através da implementação de tabelas de dispersão (Hash Tables) para o gerenciamento e otimização da memória utilizada. As anál... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
393

Communications solution for refugee settlement : Investigation of nRF24L01+ modules for use in a communications network

Engquist, Martin, Bethdavid, Simon January 2018 (has links)
The main purpose of this thesis is to test a communications solution for the second to largest refugee settlement in the world, Bidi Bidi. A solution where it is possible to inform the refugees with necessary information, for example that the water at a specific location is currently contaminated or that food is provided at another location. The idea is to use nRF24L01+ modules which operate in the 2.4 GHz frequency band and send information through various ways. This includes turning LEDs' on and off, sending text Strings and streaming audio. The results showed that the modules are too unreliable for a refugee settlement. They also showed that it is not possible to send other types' of data while streaming audio, but there could be workarounds. It is clear that more knowledge and further investigations are needed.
394

Gerenciamento de memória através da utilização de tabelas de dispersão em um módulo híbrido com suporte ao protocolo CAN (Controller Area NetWork) e ao padrão 802.15.4 ZigBee / Memory management through the use of hash tables in a hybrid module with support for the Controller Area NetWork (CAN) protocol and the ZigBee 802.15.4 standard

Estremote, Marcos Antonio [UNESP] 24 February 2017 (has links)
Submitted by MARCOS ANTONIO ESTREMOTE null (estremot@gmail.com) on 2017-11-03T20:18:22Z No. of bitstreams: 1 Tese Estremote.pdf: 11274082 bytes, checksum: d68bb503cd676b58bcfab15d1c39ba5c (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-11-13T17:35:07Z (GMT) No. of bitstreams: 1 estremote_ma_dr_ilha.pdf: 11274082 bytes, checksum: d68bb503cd676b58bcfab15d1c39ba5c (MD5) / Made available in DSpace on 2017-11-13T17:35:07Z (GMT). No. of bitstreams: 1 estremote_ma_dr_ilha.pdf: 11274082 bytes, checksum: d68bb503cd676b58bcfab15d1c39ba5c (MD5) Previous issue date: 2017-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A utilização de redes de comunicação sem fio deixou de ser uma ferramenta opcional para tornar-se uma necessidade no monitoramento de residências, automóveis, controles de processos automatizados e comunicação entre as pessoas. Tratando-se de redes de transdutores cabeadas, as redes CAN (Controller Area Network) são utilizadas em automóveis modernos, instrumentação médica, em veículos táticos, na automação de processos, no transporte metropolitano e em sistemas de controle de fábricas. A maioria das estruturas críticas de sistemas de controle fazem uso do CAN em algum ponto na rede, para conectar sensores que se encontram distantes e controlar atuadores de um sistema, ou para conectar vários controladores que utilizam uma interface em comum. O padrão sem fio, IEEE 802.15.4, comercialmente conhecido como “ZigBee”, foi projetado para operar em baixas taxas de dados, com segurança e facilidade de configurações de rede. Esta tese tem como objetivo desenvolver um sistema heterogêneo utilizando microcontroladores ATMEGA em que, o modelo do protocolo CAN e o padrão IEEE 802.15.4 estejam acoplados. Este módulo será capaz de gerenciar e monitorar sensores e atuadores utilizando CAN e, através do padrão sem fio 802.15.4, comunicar-se com os outros módulos da rede. O interfaceamento entre os pacotes da rede de controle de área (CAN) com a rede ZigBee é realizado através da implementação de tabelas de dispersão (Hash Tables) para o gerenciamento e otimização da memória utilizada. As análises realizadas de tempo de inserção, remoção e comunicação de dados, com o auxílio da técnica computacional de tabelas de dispersão para o armazenamento das informações, mostram que este procedimento favorece a comunicação entre os protocolos de redes industriais com os protocolos de redes sem fios. A economia de memória do microcontrolador com a utilização das tabelas de dispersão proposta nesta tese chegou a ser em média 750% superior do que as que não se utilizam das tabelas de dispersão. / The use of wireless communication networks is not an optional tool and become a requirement in automated systems, such as monitoring home, automobiles, automated process control and communication between people. In another aspect, wired networks, such as CAN networks, are used in modern automobiles, medical instrumentation, tactical vehicles, process automation, metropolitan transport and manufactory control systems. Many critical structures in control system use CAN network at some point, to connect sensors that are far away and to control system actuators, or to connect several controllers that use a common interface. The wireless IEEE standard 802.15.4, commercially known as “ZigBee”, is designed to operate at low data transfer rates, with security and facility of network configurations. This thesis aims to develop a heterogeneous system using ATMEGA microcontrollers in which the CAN protocol model and the IEEE standard 802.15.4 are coupled. This module is capable of managing and monitoring sensors and actuators using CAN and, through the IEEE standard 802.15.4, communicating with the other modules in network. The interface between the CAN network packets with the ZigBee network is performed through the implementation of Hash Tables to manage and optimize the memory used. The analysis of time of insertion, delete and data communication, with the aid of the computational technique of hash tables for the storage of information, show that this procedure favors the communication between the protocols of industrial networks with protocols of wireless networks . The memory economy of the microcontroller with the the hash tables proposed in this thesis was on average 750% higher than those without the hash tables.
395

Sistema inteligente de controle e monitoramento de ambiente de laborat?rios de an?lises qu?micas

Silva, Artejose Revoredo da 20 July 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-13T14:35:43Z No. of bitstreams: 1 ArtejoseRevoredoDaSilva_DISSERT.pdf: 15158528 bytes, checksum: 4aa5411704db7ed0abe93c1d6be7b4b5 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-26T14:53:00Z (GMT) No. of bitstreams: 1 ArtejoseRevoredoDaSilva_DISSERT.pdf: 15158528 bytes, checksum: 4aa5411704db7ed0abe93c1d6be7b4b5 (MD5) / Made available in DSpace on 2017-01-26T14:53:00Z (GMT). No. of bitstreams: 1 ArtejoseRevoredoDaSilva_DISSERT.pdf: 15158528 bytes, checksum: 4aa5411704db7ed0abe93c1d6be7b4b5 (MD5) Previous issue date: 2016-07-20 / Os laborat?rios de an?lises qu?micas, por se constitu?rem em um conjunto de testes e procedimentos, usando produtos e equipamentos espec?ficos para tratar dos resultados nas amostras que s?o testadas, est?o sempre sujeitos aos fatores inerentes ao ambiente. Devido a esse fato, controlar fatores como a temperatura e a umidade relativa do ar ? tarefa primordial, para que os processos desenvolvidos dentro de tais ambientes (laborat?rios de an?lises qu?micas) possam ser repetidos dentro dos par?metros exigidos. Buscando propor mecanismos de controle para ambientes, mais especificamente para laborat?rios de an?lises qu?micas, neste trabalho, apresentamos um sistema baseado em rede de sensores e reconhecimento de padr?es para controle inteligente de ambientes. Nosso prot?tipo utiliza os pr?prios dados gerados pelos sensores distribu?dos pelo ambiente, para identificar um padr?o de comportamente. Atrav?s da utiliza??o de algoritmos de aprendizado de m?quina, identificam-se as classes contidas nos dados (agrupamento), treina-se e testa-se o sistema (algoritmos de classifica??o), para que o mesmo consiga generalizar o que foi aprendido. Por ?ltimo, criam-se regras de controle associadas as classes previamente identificadas, para controlar os aparelhos de ar condicionado, tanto o principal quanto o reserva, e mais o desumificador. Dessa forma, o prot?tipo mant?m temperatura e umidade estaveis de forma inteligente.
396

Detecção e análise de movimentos do cotidiano via interface Arduino / Detection and analysis of daily movements via Arduino interface

Aquino, Raphael de Jesus Lisboa 28 July 2016 (has links)
The gap between technologies produced by science and physics basic education is noticeable. The physical programming Arduino platform has great potential for educational, artistic and commercial applications to perform as good technological inclusion tool, technical expertise and methodological review in high school. The use of laboratory equipment in the science teaching is common goal among educators. This work guides teachers to assemble sophisticated equipment in order data acquisition some daily movements, such as free falls or vehicular movements. In comparision with other alternatives, this equipment is advantageous, with technical features such as high portability, low cost and good adaptability. The implementation of the proposal in an instrumentation class for physical education and two high school year 1 of the groups demonstrated a connection between physics and technology, foster interest in physics programming and improve the contextualization of kinematics with other branches of activity human increasing the chances of a meaningful learning. / É perceptível a distância existente entre tecnologias produzidas pela ciência e o ensino de física na educação básica. A plataforma Arduino de programação física tem grande potencial para aplicações didáticas, artísticas e comerciais, constituindo uma boa ferramenta de inclusão tecnológica, conhecimentos técnicos e revisão metodológica no ensino médio. O uso de equipamentos laboratoriais no ensino de ciência é meta frequente entre educadores. O presente trabalho ensina professores a montar um equipamento de aquisição de dados para alguns movimentos cotidianos ainda que rápidos, tais como quedas livre, ou movimentos veiculares ou pendulares. Em relação a outras alternativas, este equipamento é vantajoso em quesitos como portabilidade, custo e adaptabilidade a outros projetos didáticos. A aplicação da proposta em uma turma de instrumentação para o ensino de física e em duas turmas do 1º ano do ensino médio demonstrou aproximar Física e tecnologia, fomentar interesse em programação física e melhorar a contextualização da cinemática com outros ramos da atividade humana aumentando as chances de uma aprendizagem significativa.
397

Digital Fabrication and Open Concepts : An emergent paradigm of consumer electronics production

Andersson, Pär January 2015 (has links)
Open Source och relaterade mjukvarukoncept och utvecklingsmodeller är vid det här laget allmänt bekanta och har varit föremål för många studier. Open Source Hardware är mindre spritt och studerat, och så även emergent teknologi som för in traditionellt industriella tekniker som 3D-printing, laserskärare, och CAD-baserade produktionsverktyg i mindre skala i hem- och hobbymiljöer. Dessa ämnen har främst studerats ur mer renodlat tekniska perspektiv, snarare än att sättas i samband i en vidare kontext. Denna kombinerar internet som infrastruktur och socialt medium för kunskaps- och resursdelning; open source-koncept; de möjligheter som tillgängligheten av mer och mer kapabel och överkomlig hårdvara byggd på öppen design bereder; och andra relaterade socio-tekniska fenomen vilka börjat framträda de senaste 5-10 åren. I denna uppsats undersöker jag denna större kontext. Uppsatsen har utförts i form av en litteraturstudie av existerande forskning inom ovanstående diskreta områden, och i den mån de finns även dess inbördes relationer. Denna kontext framträder som ett emergent paradigm kring produktion av hemelektronik, och även som exemplifierande trenden av teknologins fortsatta intåg som allestädes närvarande i våra liv och vår omgivning. Resultaten indikerar en gryende förändring i hur vi interagerar med teknik, vilka som gör det och varför, i vilka kontexter, och ett framträdande av en ny ekonomi. Jag visar på att ytterligare forskning behövs, och att perspektivet bör flyttas från att analyseras enbart i diskreta termer som teknik, open source-principer, DIY et cetera, utan även till vad som framstår som resultatet där dessa konvergerar, den naturliga konsekvensen av ett folkligt anammande av denna teknik och open source-koncept.
398

Design och konstruktion av roterande LiDAR-system för 360 graders objektdetektering

Ask, Simon, Lindh, Rickard January 2017 (has links)
Although laser rangefinder technologies have been around for decades in military, cartography, building, industrial and research applications it is only in recent years that more generally applicable and cheaper consumer grade laser range finder sensors have become available. This project investigates the possibilities and limitations of creating a mobile 360 degree, two-dimensional obstacle detection system using off-the-shelf available electronic components. Using a Lidar Lite 3 from Garmin Ltd., an Arduino compatible microcontroller based on Atmel 328P, a Raspberry Pi 3 from The Raspberry Pi Foundation and an electronic speed controlled brushless DC motor driving the rotation, it is shown how range data measurements can be collected, communicated, processed and displayed at measurement rates between 500 and 1000 Hz. At 5 Hz update rate of a complete 360-degree data set, this translates to a worst case angular resolution of 2.5 degrees at ranges reaching 10 meters depending on target reflectivity. Configured for these faster measurement rates, at static measurements of a white painted wall, the measurements show a standard deviation of 0.06 m at a five-meter range, going up to 0.19 m at a range of 10 meters. A modular and mobile prototype was designed and built. The modularity allowed testing and verification of two configurations. Configuration A uses a slip ring for power and data transfer to the rotating sensor. Configuration B allows the laser range finder to be stationary and instead rotates a first surface aluminum mirror positioned at 45 degrees above the sensor. The measurement results show that increasing range has a notable adversely effect on the number of successful readings in a setting demanding faster measurement rates of above 500 Hz. The number of successful readings decreases at ranges above 5 meters, and this decrease of successful readings is more pronounced in the configuration using a mirror to reflect the measurement. The mirror reflected version does on the other hand allow an electromechanically simpler, more silent and durable system. Using a density based clustering algorithm it is shown how person sized objects in the point cloud data can be robustly detected at ranges up to 5 meters.
399

Uppskattning av färgnivå genom lastcellsimplementering : Högskoleingenjörsarbete i Maskinteknik

Rigestam, Lucas January 2017 (has links)
This report presents a final degree project in mechanical engineering which was performed at Ball Beverage Packaging Fosie AB, Malmoe. The goal of the project was to create a system that could estimate the amount of paint available in a machine that colorizes aluminum cans. The environment that the system was mounted in is demanding and has high requirements on strength, stability and toughness against splashes of ethanol and water-based paint. Moreover, the company initially demanded that the project only used existing holes on the machine for adding equipment. In order to choose a measurement technology for the system, literature studies were performed on laser, ultrasonic devices and weight measurement. These studies were the foundation for a concept analysis using a Pugh’s matrix.Furthermore, with the help of the Pugh’s matrix, the project was directed towards estimating the amount of paint by measuring the weight using load cells. The collected data was supposed to be handled by an Arduino uno R3 board. Following the decision of a direction, seven concepts were designed in Autodesk Inventor with regards to mounting in existing positioning pin-holes.The last concept was manufactured with own hands – under supervision – by processing aluminum rods. Parallel to the manufacturing, the electronic system was programmed and tested by both step-wise removing identical weights, and a by measuring a continuous weight decrease caused by water escaping from a container with holes. The results of these tests showed that the system could perform the desired function.The result of the manufactured concept confirmed that the system could work with the machine but the position in the positioning pin-hole was not optimal as the forces were too low. By creating a provisional mount and testing the system beneath the paint container, it was concluded that the position accumulated more forces. This resulted in an approved modification of the container holder for a permanent mount of the load cell. Followed by this, a large amount of tests showed that the system had good potential of working with the machine but a mount beneath the container was not good as friction from mounting screws had great effect on the read values. / Rapporten behandlar ett kandidatarbete i maskinteknik som utfördes på Ball Beverage Packaging Fosie AB, Malmö. Syftet med arbetet var att skapa ett system för uppskattning av färgmängd i en maskin som färglägger aluminiumburkar. Miljön som systemet monterades i ställde höga krav på hållfasthet, tillförlitlighet och motståndskraft mot stänk från etanol och vattenbaserad färg. Initialt ställde företaget preliminära krav på att endast existerande hål på färgverket fick användas. För att välja givare till systemetutfördes litteraturstudier med avseende på laser, ultraljud och viktavläsning, vilket låg till grund för konceptvalsanalys med en Pughsmatris.Med hjälp av Pughsmatrisen riktades projektet in på att uppskatta färgmängden genom viktavläsning med lastceller, vars data skulle hanteras av ett Arduino uno R3 kort. Detta efterföljdes av att sju koncept skapades i Autodesk Inventor för infästning i existerande sprinthål på kisthållaren. Det sista konceptet tillverkades genom att på egen hand – under uppsikt –maskinbearbeta aluminiumstavar. Parallellt med tillverkningen programmerades och testades elektroniken med stegvis borttagning av vikt och kontinuerligt avrinnande vatten från hålig behållare, vars resultat visade på att systemet klarar den tänkta funktionen. Resultatet av det maskintillverkade konceptet visade att systemet även fungerade på färgverket men att positionen i sprinthålet inte var optimal då för lite krafter upptogs. Genom att tillverka en provisorisk monteringssats och testa systemet monterat under färgkistan påvisades att denna position tog upp avsevärt mer kraft. Detta medförde att kisthållaren maskinbearbetades för permanent montering av lastcell. Ett stort antal olika tester efter slutlig montering visade att systemet har goda möjligheter för att fungera med färgläggningsmaskinen men att montering under kisthållaren inte var lämplig eftersom friktion från bland annat inspänningsskruvar hade betydandeinverkan på de avlästa värdena.
400

Arduino Based Hybrid MPPT Controller for Wind and Solar

Assaad, Michael 12 1900 (has links)
Renewable power systems are becoming more affordable and provide better options than fossil-fuel generation, for not only the environment, but a benefit of a reduced cost of operation. Methods to optimize charging batteries from renewable technologies is an important subject for off-grid and micro-grids, and is becoming more relevant for larger installations. Overcharging or undercharging the battery can result in failure and reduction of battery life. The Arduino hybrid MPPT controller takes the advantage of solar and wind energy sources by controlling two systems simultaneously. The ability to manage two systems with one controller is better for an overall production of energy, cost, and manageability, at a minor expense of efficiency. The hybrid MPPT uses two synchronous buck DC-DC converters to control both wind and solar. The hybrid MPPT performed at a maximum of 93.6% efficiency, while the individual controller operated at a maximum 97.1% efficiency when working on the bench test. When designing the controller to manage power production from a larger generator, the inductor size was too large due to the frequency provided by the Arduino. A larger inductor means less allowable current to flow before the inductor becomes over saturated, reducing the efficiency of the controller. Utilizing a different microcontroller like the PIC16C63A produces a much faster frequency, which will reduce the inductor size needed and allow more current before over saturation.

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