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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.
1

Strontium -90 Radiation Detection

Jia, Jingyi January 2014 (has links)
The objective of this thesis is to construct a measurement system, measuring Radiation from Strontium with mass number 90 ( 90 Sr). The absorbed beta particle has a kinetic energy of 546 keV. The constructed scanning system makes it possible to sweep over a larger area than the actual Silicon detector. The used detector has an area of 1cm 2 . [1] A Si detector is connected to an electronic read out circuit. The Arduino microcontroller reads the output of the circuit and translates it to digital signals and sends them to a personal computer. After one signal has been read, Arduino will discharge the peak detector in the circuit to read another signal. The Arduino control software Processing will receive and process the digital output from Arduino. There will be three windows showing the number of counts from Arduino, the movement of the steering engine controlled by Thorlabs, and the sum counts of every position where the detector is.
2

TECNOLOGIAS BASEADAS NA LUZ: ABORDAGEM CONTEXTUALIZADA E INTERDISCIPLINAR ENTRE FÍSICA E QUÍMICA

Cipriano, Aline 15 December 2017 (has links)
Submitted by Evy Augusto Salcedo Torres null (evy.salcedo.torres@ufsc.br) on 2017-12-27T09:19:13Z No. of bitstreams: 2 Tecnologias baseadas na luz corrigida1 protegido.pdf: 2534128 bytes, checksum: 50d98f810f55b6e89135847b5a320bb2 (MD5) Produto AlineCipriano - Cópia.pdf: 925084 bytes, checksum: b5f470cd1252060a85442e7448a4ead1 (MD5) / Made available in DSpace on 2017-12-27T09:19:13Z (GMT). No. of bitstreams: 2 Tecnologias baseadas na luz corrigida1 protegido.pdf: 2534128 bytes, checksum: 50d98f810f55b6e89135847b5a320bb2 (MD5) Produto AlineCipriano - Cópia.pdf: 925084 bytes, checksum: b5f470cd1252060a85442e7448a4ead1 (MD5) Previous issue date: 2017-12-15 / A presente dissertação aborda uma sequência de procedimentos educacionais voltada à contextualização e a interdisciplinaridade entre os componentes curriculares, física e química. Fundamentada na teoria Histórico Social de Lev Vygotsky, visa possibilitar a construção de conhecimento através da relação dos conceitos de física e química, trabalhados em sala de aula com tecnologias baseadas na luz, a partir da técnica de grupo focal. Para tal, foi desenvolvido um Produto Interdisciplinar Didático composto por um esquema de funcionamento do espectrofotômetro UV visível com a plataforma Arduino, que estará inclusa no Manual de Apoio ao Professor (Apêndice A). O Manual poderá ser utilizado como ferramenta didática no processo de ensino aprendizagem para professores de física e química, objetivando minimizar a dificuldade dos alunos em relacionar os conceitos teóricos e seus respectivos fenômenos com a realidade norteadora. A pesquisa educacional foi efetivada, em uma escola particular de ensino, no Município de Criciúma/SC, no início de 2017. Resultados satisfatórios foram obtidos a partir das diferentes interações que fizeram parte dos processos intrapessoal e interpessoal de aprendizagem.
3

Troubleshooting Scania Vehicles, Marine and Industrial Engines with External Sensors

Kiffer, Oliver January 2015 (has links)
One factor controlling a vehicles total cost is the time it is available to generate revenue for the customer, time spent in a repair shop decreases that amount. Scania vehicles are equipped with onboard diagnostics which produces fault-codes if the internal signals deviate from their intended values. These fault codes are not always enough to isolate the problem which means that the workshop staff are required to use external measuring systems to diagnose the vehicle. Combining data from internal sensors with an external measuring system can be problematic and the results inconclusive. This thesis presents a solution where signals from external and internal sensors can be logged and analyzed together. A study on various hardware typologies are presented, key problems are identified and discussed. A prototype was created based on the research done during this project. This prototype was successfully used to troubleshoot and find a problem on a test rig where an error had been purposely introduced, reducing the whole troubleshooting process to a fraction of the time it normally takes. The hardware and software necessary to create this prototype is described in this thesis. / Konceptutveckling och prototypframtagning hur man ska kunna implementera externa sensorer till ett fordon f¨or att kunna fels¨oka snabbare och enklare. Olika plattformar unders¨oktes med f¨or- och nackdelar. Efterforskning resulterade i en f¨orsta prototyp best˚aende av mikrokontroller och f¨orslag till PCB designen.
4

Įterptinė programinė būsto apšvietimo valdymo sistema / Embedded system for house lighting managment

Matulevičius, Artūras 21 August 2013 (has links)
Šiame darbe sukurta automatizuota būsto apšvietimo valdymo sistema. Ji veikia, naudojant 8 bitų mikrokontrolerį. Programuojant naudojama Proccesing programavimo kalba, labai artima C/ C++ kalboms. Sistema leidžia nuotoliniu būdu įjungti/išjungti apšvietimą atskirose patalpose, automatiškai šviesą įjungia, įėjus į patalpą, kai yra tamsu, leidžia keisti apšvietimo spalvą. Ji skaičiuoja žmonių, esančių patalpoje, skaičių, todėl neišjungia šviesos, kol kambaryje yra bent vienas žmogus.Sistemą galima sėkmingai valdyti naudojant tiek interneto naršyklę, tiek specialiais mygtukais, esančiais šalia ekranėlio. / In this work the automatized house lighting system has been created. It works using the microcontroller of 8 bites. The programing language similar to C/ C++ languages is used. The system allows remotely turning on/off the illumination in separate rooms, automatically turns on the light entering the room when it is dark, and allows changing the illumination color. It also counts the number of people present in a room and in this way does not turn the lights off if there is one person inside. The system can be controlled by both the Internet browser and special buttons near the screen.
5

Physique et ingénierie des catastrophes naturelles : techniques accélérométriques et optiques pour le suivi de pénétration d'intrus solides dans des sols liquifiés / Physics and engineering of natural catastrophes : accelerometric and optical techniques to tracking solid intruder’s penetration into liquefied soils

Sanchez Colina, Gustavo Antonio 23 September 2016 (has links)
Cette thèse porte sur le développement de méthodes et techniques expérimentales pour mieux connaître les principes à l’oeuvre dans les glissements de terrains, les avalanches, les écoulements granulaires qui ont un grand rôle dans la liquéfaction des sols, ayant pour conséquences possibles la chute ou l’enfoncement de bâtiments. On conjugue ici des expériences de géophysique expérimentale avec des expériences de physique des milieux granulaires, et en parallèle on développe des appareils de mesure basés sur des microcontrôleurs et capteurs embarqués. / The subject of this thesis are the methods and experimental technics to help in the assessment of the underlying principles for the landslides, runaways and the other phenomena playing a main role in soil liquefaction and hence, on the falling or settling of buildings. This thesis conjugates geophysics’ to granular materials physics’ experiments, and it allowed to develop new measurement devices based on embedded microcontrollers.
6

Goniofotometr / Goniophotometer

Ivor, Martin January 2020 (has links)
The thesis deals with the design of a goniophotometer and the GUI (Graphical User Interface), capable of evaluating the photometric parameters of light sources and luminaires. The introduction contains theoretical information about photometry, photometric parameters, light sources, lamps, as well as the theory of measuring these parameters, and basic globally used data formats, designed to store the parameters of light sources. The core of this thesis, then describes the hardware, that makes up the proposed device, and the software needed to control the measurement process, visualization and storing the results. The conclusion is an evaluation of the functionality of the described device, and the measurements that were mediated by it, and an overall summary of the results achieved.
7

PostIB : Framtagning av produkt för notifikation av post

Husein, Bassam, Al-Maeeni, Ihab January 2021 (has links)
PostIB tillhandahåller en produkt som skall kunna lämna en notifikation när brev eller paket anlänt till mottagarens brevlåda. Dessa notifikationer skall presenteras hemma för användaren. Då produkten inte finns på svenska marknaden, sattes projektplanen upp tillsammans i projektgruppen, där mål och krav definierades.   Arbetsprocessen inleddes med en marknadsanalys samt en kundundersökning, för att ta reda på samtliga möjliga lösningar för denna produkt. Genom kundundersökningen kunde man ta reda på vad potentiella kunder skulle vilja ha för funktioner i produkten. Den slutgiltiga rapporten i marknadsanalysen visade att befintliga produkter finns, men saknade en del av vad projektgruppen söker.   PostIB plattform konstruerades samt utvecklades på ett sådant sätt där möjlighet för vidareutveckling finns. Då produkten inte är likt marknads konkurrenter, är denna innovation mer anpassad för den digitaliserade marknaden.   Projektet delades upp i olika faser för att uppnå ett framgångsrikt resultat av produkten. En planering över hur arbetet skulle gå till väga utfördes, där funktioner och algoritmer sattes upp. Den andra delen av arbetet var struktur och konstruktion. Under denna del fick projektgruppen göra en utvärdering av samtliga sensorer samt implementera konstruktionsfasen. I avslutande fas av projektet sammanfogades samtliga delar, där en slutgiltig prototyp presenterades.   Slutresultatet av produkten resulterade en slutgiltig funktionell prototyp som kan skicka en notifikation i form av en signal till en mottagare som i sin tur presenterar signalen grafiskt på ett användargränssnitt.   Prototypen motsvarade projektgruppens förväntningar men hade önskats att utvecklas ännu mer utifrån gruppens preferenser. Dessa önskemål bedömdes slutligen som ett projekt för vidareutveckling. / PostIB provides a product that should be able to provide a notification when a letter or package arrives at the recipient's mailbox. These notifications must be presented to the user at home. As products are not available on the Swedish market, the project plan was put together in the project group, where goals and requirements are defined.     The work process began with a market analysis and a customer survey, to find out all possible solutions for this product. Through the customer survey, it was possible to find out what potential customers would like for features in products. The final report in the market analysis showed that existing products exist but lacked part of what the project group is looking for.     PostIB platform was designed and developed in such a way where there is opportunity for further development. As the product is not like market competitors, this innovation is more adapted to the digitalized market.    The project was divided into different phases to achieve a successful result of the product. A planning of how the work would proceed was carried out, where functions and algorithms were set up. The second part of the work was structure and construction. During this part, the project team had to make an evaluation of all sensors and implement the design phase. In the final phase of the project, all parts were joined together, where a final prototype was presented.    The end result of the product resulted in a final functional prototype that can send a notification in the form of a signal to a receiver which in turn presents the signal graphically on a user interface.    The prototype met the project group's expectations but had wanted to develop even more based on the group's preferences. These wishes were finally assessed as a project for further development.
8

Brailled : A Braille translation aid / Punktskriftsöversättare

Dandanell, Josefin, Henriksson, Agnes January 2021 (has links)
The purpose of the project was to develop a product that would serve as a support for the learning of Braille. Learning Braille is a time consuming process. People who have recently suffered a visual impairment have a lower sensitivity to touch than those who have been visually impaired for a longer period. According to a study [1], the learning process can lead to depression. At the same time, the technology for support systems for the visually impaired is underdeveloped. The questions examined in the project were partly about the environment’s influence on the accuracy of the instrument’s translation of Braille. Partly, if it was possible to create an instrument that can translate Braille in standard format and at the same time be a suitable aid for a user with a visual impairment. The instrument consisted of four main parts; reading surface, reading head, audio output and keyboard. The purpose of the reading surface was to place the Braille to be translated under the reading head using a stepper motor. The reading head would then interpret the letter, which would then be called out as an audio file using the audio output. All operations of the instrument would be controlled by a keyboard with three push buttons. The resulting product was promising. The analysis showed that it was fully possible to create a functioning Braille translator. However the product requires some further development in order to be used as an effective aid / Syftet med projektet var att ta fram en produkt som skulle fungera som ett stöd för inlärning av punktskrift. Personer som nyligen drabbats av en synskada har sämre känslighet för beröring än de som varit synskadade under en längre period. Enligt en studie [1] kan tidskrävande inlärningsprocessen leda till depression, samtidigt som tekniken för stödsystem åt synskadade är underutvecklad. De frågeställningar som undersöktes i projektet handlade dels om omgivningens påverkan av exaktheten av instrumentets översättning. Dels om det var möjligt att skapa ett instrument som kan översätta punktskrift i standardformat och samtidigt vara ett passande hjälpmedel för en användare med en synskada. Instrumentet bestod av fyra huvudsakliga delar; avläsningsyta, avläsningshuvud, ljudutgång samt tangentbord. Avläsningsytans syfte var att placera punktskriften som skulle översättas under anläsningshuvudet med hjälp av en stegmotor. Avläsningshuvudet skulle därefter tolka bokstaven som sedan skulle utropas som en ljudfil med hjälp av ljudutgången. Instrumentets samtliga operationer skulle styras av ett tangentbord med tre tryckknappar. Resultatet av den framtagna produkten var lovande. Undersökningarna påvisade att det var fullt möjligt att skapa en fungerande översättare. Dock krävs det en vidareutveckling för att produkten skall kunna användas som etteffektivt hjälpmedel.
9

Evaluation of Low-Cost Water Quality Measurement System

Jiang, Meng January 2015 (has links)
Water is a very important element in our daily life, being able to check the water quality by ourselves would be a useful project to improve our life quality. My idea is to create something cheap and easy to examine the water quality and test it to see if it is capable for outdoor using as well. In this project I chose a DS18B20 as a temperature sensor. To get a system which can work as a water pump I chose an L298P as a motor driver board to support the electric motor, a Hall flow meter to get the flow and quantity, and a Water sensor to get the conductivity. With the Arduino and the Visual Studio user interface program, the system can extract the data that we want. The result of the measurement shows it is possible to analyse the water quality by comparing the conductivity of the known liquid to a test sample in a controlled environment. The system shows great promise of being a cheaper and easier system but still needs to improve accuracy, by reducing outside influence (like temperature), thereby enabling the system to work in more harsh environments.
10

Development of a Cost Effective Wireless Sensor System for Indoor Air Quality Monitoring Applications

Abraham, Sherin 05 1900 (has links)
Poor air quality can greatly affect the public health. Research studies indicate that indoor air can be more polluted than the outdoor air. An indoor air quality monitoring system will help to create an awareness of the quality of air inside which will eventually help in improving it. The objective of this research is to develop a low cost wireless sensor system for indoor air quality monitoring. The major cost reduction of the system is achieved by using low priced sensors. Interface circuits had to be designed to make these sensors more accurate. The system is capable of measuring carbon dioxide, carbon monoxide, ozone, temperature, humidity and volatile organic compounds. The prototype sensor node modules were developed. The sensor nodes were the connected together by Zigbee network. The nodes were developed in such a way that it is compact in size and wireless connection of sensor nodes enable to collect air quality data from multiple locations simultaneously. The collected data was stored in a computer. We employed linear least-square approach for the calibration of each sensor to derive a conversion formula for converting the sensor readings to engineering units. The system was tested with different pollutants and data collected was compared with a professional grade monitoring system for analyzing its performance. The results indicated that the data from our system matched quite well with the professional grade monitoring system.

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