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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

Desenvolvimento de um kit didático experimental para o ensino de resistores, capacitores e circuitos de temporização RC / Development of an experimental teaching kit for the teaching of resistors, capacitors and timing circuits RC

Bratti, Vatison Mauro 23 February 2018 (has links)
Acompanha: Produto educacional: Desenvolvimento de um kit didático experimental para o ensino de resistores, capacitores e circuitos de temporização RC / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O Ensino de Física tem sofrido inúmeras transformações nas últimas décadas, discute-se muito sobre a inserção de diferentes recursos didáticos em sala de aula a fim de gerar um ambiente de aprendizagem diferente do tradicional, bem como proporcionar condições de uma aprendizagem efetiva para o aluno. O sistema tradicional do ensino de Física vem perdendo aos poucos a eficácia, o significado e até mesmo o interesse por parte do aluno em buscar conhecimento. O convívio constante com as mídias de maneira inapropriada tem provocado uma imensa perda de tempo, tornando-se um adversário desleal contra o estudo, restando assim pouco tempo para a aprendizagem. Nesse sentido, esse trabalho tem como objetivo o desenvolvimento de um novo método com uma proposta experimental e investigativa, baseado na teoria de Vygotsky, visando despertar no educando o interesse e a busca pelo saber, uma vez que ele é parte principal do processo, e que a partir de seus conhecimentos prévios é que o professor introduz seu conhecimento, proporcionando melhor interação entre professor e aluno, e também propiciando o desenvolvimento cognitivo e social no ambiente escolar. O kit didático experimental desenvolvido torna-se uma ferramenta de grande valia, que possibilita ao professor trabalhar um método diferenciado onde ele poderá relacionar a parte teórica com a parte prática, possibilitando com o kit trabalhar o conteúdo de resistores e capacitores por completo, de um modo que despertará no aluno um maior interesse. A tecnologia utilizada para o desenvolvimento do kit foi a plataforma de desenvolvimento Arduino que é composta por um microcontrolador e periféricos, devido ao fácil acesso a materiais didáticos disponíveis, possibilitando a fácil reprodução do protótipo futuramente por pessoas com pouco conhecimento na área e por ser uma plataforma open-source. Esse produto desenvolvido vem ao encontro das politicas de inclusão propostas pelos governos, que tem o objetivo de incluir na sociedade pessoas com necessidades educacionais especiais, pensando nisso, essa ideia vem contribuir e dar suporte a alunos com deficiências auditiva ou visual, bem como os demais alunos do ensino regular ou até mesmo superior, que necessitam estudar o conteúdo abordado aqui. / The teaching of physics has undergone numerous transformations in the last decades, much is discussed about the insertion of different didactic resources in the classroom in order to generate a learning environment different from the traditional one, as well as to provide conditions of an effective learning for the student. The traditional system of physics teaching has gradually lost its effectiveness, meaning and even the student's interest in seeking knowledge. The constant conviviality with the media in an inappropriate way has caused an immense loss of time, becoming an unfair opponent against the study, thus leaving little time for learning. In this sense, this work aims to develop a new method with an experimental and investigative proposal, based on Vygotsky's theory, aiming to awaken in the student the interest and the search for knowledge, since it is a main part of the process, and that from their previous knowledge is that the teacher introduces their knowledge, providing better interaction between teacher and student, and also fostering cognitive and social development in the school environment. The developed experimental teaching kit becomes a valuable tool that allows the teacher to work a different method where he can relate the theoretical part to the practical part, allowing the kit to work the contents of resistors and capacitors completely, so that the student will be more interested. The technology used for the development of the kit was the Arduino development platform which is composed of a microcontroller and peripherals, due to the easy access to available didactic material, allowing the easy reproduction of the prototype in the future by people with little knowledge in the area and being a open-source platform. This developed product is in line with the inclusion policies proposed by governments, which aims to include people with special educational needs in society. With this in mind, this idea contributes to and supports students with hearing or visual impairments, as well as other students of regular or even higher education, who need to study the content covered here.
172

Desenvolvimento de um fotômetro LED-Vis portátil e microcontrolado por Arduino / Development of a LED-Vis photometer with a portable and Arduino microcontroller

Pontes, Aline Santos de 28 April 2014 (has links)
Made available in DSpace on 2015-05-14T13:21:35Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 5352516 bytes, checksum: 794641cb921c8b2deee06ca5e6ee12ed (MD5) Previous issue date: 2014-04-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / A portable and low-cost photometer is proposed in this work. The instrument uses a tri-color light emitting diode (LED) as its radiation source in maximum emission wavelengths of 480 (blue), 534 (green) and 630 nm (red). It employs a phototransistor with spectral sensitivity in the visible region, as well as an Arduino microcontroller. Its analytical performance was evaluated by means of quantitative analysis (analytical curves), whose models were validated by analysis of variance (ANOVA). The instrument was applied to determine sunset yellow dye in energy drinks and sodas, and potassium permanganate pills. For comparison purposes, a commercial spectrophotometer was used to construct the calibration curves for the reference method. Applying the paired t-test at a 95 % confidence level for the concentration results obtained with the two instruments, we observed no statistically significant difference. Furthermore, accurate concentration estimates were obtained for the analytes as confirmed by the low relative standard deviation range of 0.2 and 0.5%, respectively, for both the dye and the permanganate. The proposed photometer might be an economically viable alternative to spectroscopic analysis, especially in teaching laboratories with limited financial resources or lacking in highly qualified personnel. / Um fotômetro portátil e de baixo custo é proposto neste trabalho. Esse instrumento utiliza um diodo emissor de luz (LED-Light Emitting Diode) tricolor como fonte de radiação nos comprimentos de onda do máximo de emissão de 480 (azul), 534 (verde) e 630 nm (vermelho). Além disso, emprega um fototransistor com sensibilidade espectral na região do visível como fototransdutor, bem como um microcontrolador Arduino como unidade de controle. Seu desempenho analítico foi avaliado por meio de análises quantitativas baseadas em curvas analíticas, cujos modelos foram validados por meio da Análise de Variância (ANOVA). O instrumento foi aplicado à determinação do corante amarelo crepúsculo em amostras de refrigerantes e bebidas energéticas e de permanganato de potássio em amostras de medicamentos. Para fins de comparação, um espectrofotômetro comercial foi empregado para construir as curvas analíticas do instrumento de referência. Aplicando o teste t-emparelhado ao nível de 95% de confiança para os resultados de concentração obtidos com os dois instrumentos, observa-se que não houve diferença estatisticamente significativa. Ademais, resultados precisos nas estimativas das concentrações dos analitos foram obtidos sendo atestado pelo baixo desvio padrão relativo conjunto de 0,2 e 0,5%, respetivamente, para o corante e permanganato. O fotômetro proposto pode ser uma alternativa economicamente viável para análises espectrométricas, sobretudo, em laboratórios de ensino com poucos recursos financeiros e carentes de pessoal altamente qualificado.
173

Att välja hårdvaruplattform för Internet of Things projekt : En jämförelse mellan Raspberry Pi och Arduino

Jonsson, Marcus January 2017 (has links)
The work described in this thesis is aimed at comparing Raspberry Pi model 3 B and Arduino Uno with an ESP8266 wifi module to see which one is most suitable to use in a Internet of Things project where data collecting from an sensor, processed and then presented. The method for this comparison is to divide the work. First, price and power consumption will be evaluated. Then, the stability of communication over wifi will be tested. Finally, the time it takes to design a program on the platforms will be measured. The result from the comparison show that the Raspberry Pi is the best choice for this type of Internet of Things projet. However, which platform to choose depends on the specific goals of the project since the platforms are good at different things. A server written in Python communicates with the Raspberry Pi by using socket to socket communication, the Raspberry Pi collects the data from the sensor and then sends it to the server. The server then saves the data in a database by the unit identification number. Then a webpage was designed that presented the data to the user. A usabiity test was done on the webpage and the result from the usability test showed that the test users was satisfied with the usability with the page, exept the choice of colors, which was fiexd. / Arbetet beskrivet i detta examensarbete går ut på att jämföra vilken av plattformarna Arduino Uno med en ESP8266 wifi-modul och Raspberry Pi 3 modell B som är mest lämplig att använda i ett Internet of Things projekt där inhämtning av data, bearbetning av data och presentation av datan. Metoden för arbetet är att dela upp det i olika moment, först undersökt faktorerna pris och strömförbrukning därefter testas kommunikationen över wifi för de olika plattformarna och därefter hur lång tid det tar att skapa ett test för kommunikationen på varje plattform. Resultatet av jämförelsen är att Raspberry Pi är mest lämplig för detta projekt, men att avgöra vilken plattform som ska användas i Internet of Things beror till störst del på vilka krav som finns, eftersom bägge plattformarna har sina egna fördelar mot varandra. En server skriven i python hämtar datan från sensorn via Raspberry Pi med hjälp av socketmeddelanden, därefter sparas datan i en databas där ett identifieringsnummer för plattformen styr sparandet av datan. För att kunna presentera datan från sensorn så skapades en webbplats som hämtar datan från databasen beroende på om användaren skickar en begäran från webbplatsen. Ett användartest har genomförts på webbplatsen för att undersöka användbarheten. Användartestet visade att webbplatsen hade de funktioner som användarna ansåg behövdes, enda åtgärdspunkten var färgsättning på webbplatsen som åtgärdades.
174

Trådlösåterställning av industriella ljusskydd : Trådlösåterställning av ljusridåer/ljusbommar med ett öppet lasersystem

Lindholm, Viktor January 2017 (has links)
Ljusbommar/ljusridåer är ett vanligt säkerhetsskydd på dagens industrier, där arbete görs vid rörliga delar.  Det ställs höga säkerhetskrav på ljusbommar/ljusridåer. När ett skydd bryts behöver det återställas och detta görs vanligtvis med en tryckknapp. Detta system medför ett hinder i situationer där truckar används, eftersom att arbetaren behöver kliva ur trucken för att göra återställning av skyddet. Ett trådlöst system av återställningen är lösningen på problemet, men det ställs krav på ett sådant system. Ett öppet lasersystem har valts att undersökas om det skulle kunna uppfylla de krav som ställs. För att testa om ett öppet lasersystem skulle kunna användas togs en prototyp fram. Prototypen bestod av en lasermodul som sändare och en solcell som mottagare. Systemet styrdes av två stycken mikrokontrollers som kommunicerade via UART. Prototypen testades för hur stabilt systemet var mot ljusstörningar och inom vilket område det var begränsat. Det visade sig att den prototyp som tagits fram inte fungerade när störningsljus med frekvenser i sig belyste mottagaren. Prototypens områdesbegränsning visade sig var alldeles för stor. Slutsatsen av undersökningen var att det är teoretiskt möjligt att byta ut knappen mot ett öppet lasersystem, dock inte med den prototyp som togs fram. Det behövs istället en prototyp som måste bearbetas mer för att kunna uppfylla de krav som skulle ställas för trådlösåterställning av ljusbommar/ljusridåer. / Light beams / light curtains are a common safety guard on today's industries, where work is done on moving parts. High safety requirements are imposed on light beams / light curtains. When a protection is broken, it needs to be reset and this is usually done with a pushbutton. This system in which truckers are used, a problem arises, because the worker needs to get out of the truck to repair the guard. A wireless recovery system is the solution to the problem, but it needs to meet high standards. An open laser system has been chosen to be investigated if it could meet the requirements. To test if an open laser system could be used, a prototype was taken. The prototype consists of a laser module as a transmitter and a solar cell as a receiver. The system is controlled by two microcontrollers communicating via UART. The prototype was tested for how stable the system was and in which area it was limited. It turned out that the prototype produced did not work when the interference light with frequencies in itself illuminated the receiver. The prototype area restriction proved to be too wide in the area. The conclusion of the survey was that it is theoretically possible to replace the button with an open laser system. However, not with the prototype that was presented, but with a prototype that has to be processed more to meet the requirements for wireless reset of light bombs / light curtains.
175

Processamento de áudio em tempo real em dispositivos computacionais de alta disponibilidade e baixo custo / Real time digital audio processing using highly available, low cost devices

André Jucovsky Bianchi 21 October 2013 (has links)
Neste trabalho foi feita uma investigação sobre a realização de processamento de áudio digital em tempo real utilizando três dispositivos com características computacionais fundamentalmente distintas porém bastante acessíveis em termos de custo e disponibilidade de tecnologia: Arduino, GPU e Android. Arduino é um dispositivo com licenças de hardware e software abertas, baseado em um microcontrolador com baixo poder de processamento, muito utilizado como plataforma educativa e artística para computações de controle e interface com outros dispositivos. GPU é uma arquitetura de placas de vídeo com foco no processamento paralelo, que tem motivado o estudo de modelos de programação específicos para sua utilização como dispositivo de processamento de propósito geral. Android é um sistema operacional para dispositivos móveis baseado no kernel do Linux, que permite o desenvolvimento de aplicativos utilizando linguagem de alto nível e possibilita o uso da infraestrutura de sensores, conectividade e mobilidade disponível nos aparelhos. Buscamos sistematizar as limitações e possibilidades de cada plataforma através da implementação de técnicas de processamento de áudio digital em tempo real e da análise da intensidade computacional em cada ambiente. / This dissertation describes an investigation about real time audio signal processing using three platforms with fundamentally distinct computational characteristics, but which are highly available in terms of cost and technology: Arduino, GPU boards and Android devices. Arduino is a device with open hardware and software licences, based on a microcontroller with low processing power, largely used as educational and artistic platform for control computations and interfacing with other devices. GPU is a video card architecture focusing on parallel processing, which has motivated the study of specific programming models for its use as a general purpose processing device. Android is an operating system for mobile devices based on the Linux kernel, which allows the development of applications using high level language and allows the use of sensors, connectivity and mobile infrastructures available on devices. We search to systematize the limitations and possibilities of each platform through the implementation of real time digital audio processing techinques and the analysis of computational intensity in each environment.
176

Energetická náročnost objektu pro bydlení z pohledu regulace vytápění

Vavruška, Martin January 2019 (has links)
The diploma thesis deals with the influence of building modifications in the form of thermal insulation of the external cladding and replacement of windows on the energy performance of the building. In addition to the building modifications, the influence of heating regulation and hot water preparation on the energy performance of the building is assessed. These facts are analyzed for two older, just reconstructed, houses of similar size. Heat - technical calculations are made in the TV program of the company Protech, Nový Bor. The output is an analysis of simple return on investment in individual measures. In its second part, the thesis deals with the design of several examples of regulation. It concerns the regulation of underfloor heating, solar collector using one storage tank, solar collector using two storage tanks and automatic closing of the storage tank of the heating system. The electronics of the controllers are solved by the Arduino Mega 2560 chip. In addition to the programmable arduino chip, the three-way valve, temperature sensor and pump are used for underfloor heating. The solar system uses solar collector, temperature sensors, storage tanks, programmable Arduino chip, pumps, solenoid valve and LCD display. The automatic closing of the accumulation tank uses the solenoid valve, temperature sensor, pump and Arduino.
177

Modulární výuková platforma pro oblast vestavěných systémů a číslicových obvodů / Modular Educational Platform for Embedded Systems and Digital Circuits Domain

Koupý, Pavel January 2021 (has links)
The aim of the work is the design and implementation of two circuit boards delivering learning platforms, which will consist of two separate circuit boards with ARM MCU and a programmable FPGA gate array that will be interconnectable and appropriately complemented by peripherals. These platforms will be developed by analysing current teaching and development platform solutions and then demonstrating on practical examples. The main benefit of this work should be update and simplification of existing equipment. At the same time, there is an emphasis on greater transparency of the whole solution, so that it is not too complicated for an aspiring student to familiarise himself with modern micro-controllers and programmable gate arrays and can link the simpler units into more complex ones, where the individual boards can be used as separate working units and their interconnection will provide a computationaly stronger yet more complex device.
178

The Characterisation and Continuous Measurement of Potential Harvestable Energy of an Environment

Bajwa, Diran January 2023 (has links)
This thesis is based around the use of energy harvesting in systems, specifically for a Bluetooth Low Energy (BLE) mesh testbed. This BLE mesh is located in a well lit lab and is currently powered by mains electricity. Systems such as the BLE mesh are considered Internet of Things (IoT). The market for these systems is rapidly expanding and in turn so is the energy use. Many systems are powered by battery, and the need to replace a battery with an energy harvesting system has arisen. This thesis will explore the possibilities to power a node in this mesh and introduce a level of intelligence to allow the system to better predict available energy to harvest. The lab the BLE mesh is in is characterised for potential energy sources. Light is chosen to be an exceptional power source, from here a lux metre is created from a photovoltaic (PV) cell. This PV cell would function as both the power for the system and provide a method to measure the current light intensity. This would help add a layer of intelligence to the system to allow future systems to better understand how much energy is available. This idea can be implemented in other harvesters as well. / Denna avhandling är baserad på användningen av energiskördning i ett system, specifikt i en Bluetooth Low Energy (BLE)-mesh. Denna BLE-mesh befinner sig i ett väl upplyst labb och är för närvarande strömdrivet genom huvudström. System som BLE-mesh anses vara en del av Internet of Things (IoT). Marknaden för dessa system expanderar snabbt och därmed ökar också energiförbrukningen. Många system är batteridrivna och det har uppstått ett växande behov av att ersätta batteriet med ett energiskördsystem. Denna avhandling kommer att utforska möjligheterna att strömförsörja en nod i denna mesh och införa en intelligensnivå för att förbättra systemets möjlighet att förutspå energi som är tillgänglig för att skördas. Labbet där BLE-meshen befinner sig karakteriseras för potentiella energikällor. Ljus valdes som en exceptionell kraftkälla, och därifrån skapas en luxmeter från en fotovoltaisk (PV) cell. Denna PV-cell ska fungera både som strömkälla för systemet och utgöra en metod för att mäta nuvarande ljusintensitet. Detta skulle bidra till att lägga till ett skikt av intelligens i systemet för att göra det möjligt för framtida system att bättre förutspå tillgänglig skördbar energi. Denna idé kan även implementeras i andra energiskördsystem.
179

A Mechatronic Jar Opener : A Design Study of a Motorized Home Appliance for Improved Accessibility / En mekatronisk burköppnare : En designstudie av en motoriserad hushållsapparat för förbättrad tillgänglighet

Paulson Ramel, Charlotte, Mobrin, Sofia January 2023 (has links)
Mechatronics is a rapidly growing field that combines elements of mechanical, electrical, and software engineering to design and develop intelligent systems. One area where mechatronics still has the potential to have a significant impact is personal appliances and aids for people with disabilities, which this report aims to explore. This bachelor thesis focuses on the design and development of a mechatronic lid opener. The main objective of this project is to explore the feasibility of creating a functional prototype that can automatically open jar lids with minimal user intervention. A secondary objective is to explore the market potential for such a product. In order to achieve the main objective, a prototype was designed, constructed, and tested. Further, a brief supplementing market analysis was conducted. The result showed that the construction was durable enough to withstand the pressure it put on the jar, and the function of the planetary gearing works as intended. Although, from the tests, it is concluded that the prototype’s functionality is not developed enough to reach the goal. This is derived from the limitations of construction on the gripping arms and lack of inertia leading to premature rotation. The result also showed that the market for automated or motorized home appliances is small, with identified target groups generally having low purchasing power. Low effort is recognized to achieve what this project aimed to do, which is why future studies from this project are of high interest. / Mekatronik är ett snabbt växande område som kombinerar element av mekanik, elektronik och mjukvaruteknik för att designa och utveckla intelligenta system. Ett område där mekatronik fortfarande har potential att ha en betydande inverkan är personliga applikationer och hjälpmedel förpersoner med funktionsvariation, som denna rapport syftar till att utforska. Denna kandidatuppsats fokuserar på design och utveckling av en mekatronisk burköppnare. Huvudsyftet med detta projekt är att utforska möjligheten att skapa en funktionell prototyp som automatiskt kan öppna burklock med minimalt krav på inverkar från användaren. Ett sekundärt mål är att utforska marknadspotentialen för en sådan produkt. För att uppnå detta huvudsyfte designades, konstruerades och testades en prototyp. Vidare genomfördes en kort kompletterande marknadsanalys. Resultatet visade att konstruktionen var tillräckligt tålig för att klara trycket den satte på burken och planetväxelns funktion fungerar som planerat. Däremot dras slutsaten utifrån testerna att prototypens funktionalitet inte är tillräckligt utvecklad för att nå målet. Detta härrör från begränsningarna av konstruktionen av griparmarna och bristen på tröghet som leder till för tidig rotation. Resultatet visade också att marknaden för automatiserade eller motoriserade hushållsapparater är liten, där identifierade målgrupper generellt har låg köpkraft. Liten ansträngning anses nödvändigt för att uppnå vad detta projekt syftade till, varför framtida studier från detta projekt är av stort intresse.
180

Framtagning och optimering av en paddelsensor / Manufacture and optimisation of a paddle sensor

Mahmutovic, Adnan, Micheal, Nahome January 2020 (has links)
Syftet med detta projekt var att skapa en paddlingssensor vilket mäter paddlingskrafteni flera olika riktningar. Detta uppnås genom att skapa en sensor vars kopplingsschema är i enlighet med en wheatstonebrygga och två trådtöjningsgivare som placeras i strategiskt valda positioner. Dessa positioner tillåter sensorn att mäta flera krafter i olika riktningar. Jämfört med tidigare sensorer som endast mäter spänningsskillnaden i en riktning med endast en givare. Trådtöjningsgivarnas positionering utvärderades samt den optimala positioneringen. Sensorn som konstruerades kunde registrera spänningsförändringar som var proportionella till en pålagd vikt. En tydlig linjär korrelation observerades mellan viktökningen och spänningsförändringen. / The purpose of this project was to construct a paddle sensor that has the ability to measure the paddle force in multiple different directions. This can be attained by creating a sensor where the circuitry is in accordance with a wheatstonebridge and strain gauges are strategically placed on predetermined positions. These positions allow the sensor to be able to measure the force in different directions. The positions of the strain gauges were evaluated, and the most optimal placement was chosen. The created sensor was able to register voltage changes which were proportional to an added weight. As the weight increased so did the voltage changes and a clear linear correlation was observed.

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