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P120 – MEMS-gyroskop i rengöringsrobot : Undersöka möjligheten att använda ett MEMS-gyroskop för att säkerställa rak kurs hos poolrengöringsroboten W2000 under drift. / P120 – MEMS-gyroscope in cleaning robotEliasson, Dennis, Logge, Marika January 2018 (has links)
Detta projekt syftar till att undersöka om det går att kurskorrigera en av Weda AB:s poolrengöringsrobotar med hjälp av ett MEMS-gyroskop. Den valda rengöringsroboten styrs idag av en PLC, och konceptet är att komplettera styrenheten med ett MEMS gyroskop som kan detektera kursavvikelser. Undersökandet av möjligheterna för implementeringen börjar med att samla information om MEMS gyroskopens funktion och i vilka tekniker de används idag. Vidare utförs beräkningar mot Wedas definition av rak kurs, det resulterade i för höga krav på känsligheten i gyroskopet. Trots det otillfredsställande resultatet beslutar Weda att projektet ska fortsätta undersöka gyroskopets möjligheter. En marknadsundersöknings med 9 tillverkningsföretag genomförs i syfte att se vad marknaden erbjuder för MEMS gyroskop idag. Sedan konsulteras distribueringsföretaget Avnet som bidrar med sina kunskaper, erfarenheter och rekommendationer för konceptet. Ett av de framstående gyroskopen i undersökningen användes för att genomföra två tester. Syftet av dem var att simulera olika situationer som rengöringsroboten kan utsättas för. Resultatet visar att repetitionsnoggrannheten är god men att gyroskopet inte är tillförlitligt i låga hastigheter, vilket är en dålig egenskap för rengöringsroboten W2000 som körs med en hastighet 0,2 m/s. Testresultatet diskuterades med Bosch och dem tror att gyroskopets automatiska kalibrering är orsaken till att det inte ger tillförlitliga mätdata vid låga hastigheter. / During this project the possibilities to monitor and adjust the direction of a pool cleaning robot with a MEMS gyroscope are evaluated. The robot chosen for the evaluation is manufactured by Weda AB. The concept is to add a MEMS gyroscope to the robot, which will give the control unit (PLC) feedback regarding the direction of the robot. The evaluation includes general information about MEMS gyroscopes, where they are used, common built in errors etc. To be able to select a suitable MEMS gyroscope the needed sensitivity is calculated. The needed sensitivity is based on requirements from Weda AB. The evaluation also includes a market survey which shows that the needed sensitivity cannot be fulfilled by products available on the market. The market survey is based on nine manufacturing companies and a recommendation from a distribution company called Avnet. One of the prominent MEMS gyroscopes was used to carry out two tests. The tests were designed to mimic motions of the pool cleaning robot. The test result shows that the gyroscope has good repetition accuracy, but it is not trustworthy when the rotation speed is low. The test result was discussed with the manufacturer and they think that the non positive result is caused by the automatic calibration.
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Basstöne und ihre Bedeutungsmöglichkeiten im Kontext: Zur Logik der Klangfortschreitung und zur Modulation im GeneralbassJans, Markus 22 September 2023 (has links)
Anhand des Anfangs der Allemande aus der Französischen Suite Nr. 5 (BWV 816) werden die unterschiedlichen Bedeutungsmöglichkeiten der Basstöne und der ihnen zugehörigen Klänge untersucht. Ziel ist die Aufarbeitung und Beschreibung einer historisch gewachsenen Logik der Klangverbindung (prae-Rameau und prae-Funktionstheorie). Im Zentrum der Betrachtung steht einerseits ein Intervallfortschreitungsprinzip, das seit dem frühen 14. Jahrhundert gilt und wirksam ist (an der Schola Cantorum Basiliensis nennt man es ›Pi[iii...]P-Prinzip‹) und anderseits die aus diesem Prinzip erwachsende Oktavregel. / Based on the example of the beginning of the Allemande of the French Suite Nr. 5 (BWV 816), this paper discusses probable “meanings” (significations) of bass-notes and the chords above them. The goal is to explain and to apply a historically developed logic of sound progression (pre - Rameau and pre - functional harmony). The focus of examination is a principle of interval progression, introduced in the 14th century and valid ever since (at the Schola Cantorum Basiliensis known as “Pi[iii…]P –principle”) and the resulting Rule of the Octave.
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Evaluation of the η (Eta) nitride with three laboratory meltsLind, Martin, Johansson, Cecilia January 2015 (has links)
η (eta) nitride, Cr3Ni2SiN, is a precipitate found in high temperature austenitic stainless steel and is not yet included in Thermo-Calc steel database TCFE7. The aim of this thesis is to collect thermodynamic data to enable the addition of η nitride in the databases. Three laboratory melts with varying levels of silicon, chromium and nickel have been aged at 700-1000 °C for 75 h, 300 h and 1200 h and examined by Light Optical Microscopy, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, Wavelength Dispersive Spectroscopy, Electron Backscattered Diffraction and X-ray Powder Diffraction. η nitride is in the studied alloys an equilibrium phase stabilized with nitrogen. Presence of η nitride was confirmed by Energy Dispersive Spectroscopy and X-ray Powder Diffraction. It was found to precipitate in four different ways, at primary grain boundaries, intragranularly, as a "skeleton-like" precipitate and as a border around the occurring Cr2N precipitates. The area fraction of η nitrides increases with longer aging times and is favored by silicon and nickel. The composition of η nitride is not changing regardless of material composition, aging temperature and aging time. The composition of η nitride in all three materials are 8.7-9.7 wt.% silicon, 47-54 wt.% chromium, 1.4-4.1 wt.% iron and 33-36 wt.% nickel. The nitrogen content 2 determined by Wavelength Dispersive Spectroscopy is 2.8-3.2 wt.%. No complete equilibrium was achieved and together with incomplete mixing of the alloying elements during melting, the microstructure is difficult to evaluate. Other precipitates found are Cr2N, π nitride, σ phase and two unidentified phases, M and N. Of these phases at least Cr2N is not an equilibrium phase as it dissolves during aging. Further aging to achieve complete equilibrium is necessary.
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Synthesis, Characterization and Photophysical Studies of Porphyrin and N-Confused Porphyrin Derivatives and Self-assembled Nano-MorphologiesAcharya, Rajendra 19 August 2013 (has links)
No description available.
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Internet of things connected notification device for people who are hard of hearingHang Shek, Wai, Geiger Ferotin, Thomas January 2022 (has links)
This degree project investigates the possibility to develop and re-design an IoT solution called NOT!FY, offered by the company Omnitor. NOT!FY is used by users who are hard of hearing or deaf as a complement to an accessibility communication application. It functions by registering incoming calls and activating a relay connected to, for example, a light source, notifying the user. The current problems that Omnitor experiences with NOT!FY is its price, production difficulties, size and design. The project will take on these problems by investigating the market of programmable devices and, through comparative analysis, choosing a platform to transfer and improve upon the current NOT!FY functionalities. The devices were decided together with Omnitor and a grant calculation was drafted to evaluate which units yielded the best profit. With the help of the grant calculation, Raspberry Pi Zero W and ESP8266 were the chosen devices. A basic evaluation was performed to verify that the implemented functions of ESP8266 and Raspberry Pi Zero W functioned as intended. An in-depth evaluation and functional verification were performed on the finalized prototype. It confirmed the prototype’s functionality and the possibility to replace the current product in use by Omnitor. / Detta projekt undersöker möjligheten att utveckla och designa om en IoT-lösning kallad NOT!FY, som erbjuds av företaget Omnitor AB. NOT!FY används av döva eller hörselskadade användare som ett komplement till en tillgänglighetsanpassad kommunikationsapplikation. Den fungerar genom att registrera inkommande samtal och aktivera ett relä som är anslutet till exempel en ljuskälla för att meddela användaren. De nuvarande problemen som Omnitor upplever med NOT!FY är dess pris, produktionssvårigheter, storlek och design. Projektet kommer att ta sig an dessa problem genom att undersöka marknaden för programmerbara enheter och genom en jämförande analys välja en plattform att överföra och förbättra funktionerna från den nuvarande produkten. Enheterna bestämdes tillsammans med Omnitor och en bidragskalkyl är framtagen för att utvärdera vilka enheter som gav bäst vinst. Med hjälp av bidragskalkylen var Raspberry Pi Zero W och ESP8266 de valda enheterna. En grundläggande utvärdering utfördes för att verifiera att de implementerade funktionerna i ESP8266 och Raspberry Pi Zero W fungerade som avsett. En mer ingående utvärdering och funktionell verifiering utfördes på den färdiga prototypen. Detta bekräftade prototypens funktionalitet och möjligheten att ersätta den nuvarande produkten som används av Omnitor.
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Utveckling av webbaserat blixtdetekteringssystem / Development of a web-based lightning detection systemAl Sayfi, Anhar, Kufa, Max January 2016 (has links)
In this paper we suggest a lightning detection system capable of warning a local populous of incoming lightning weather using a combination of the AS3935 sensor and the one-board-computer Raspberry Pi, in an attempt to design a product that is cheap, mobile and easy to use. The product is composed of a sensor net that registers and reports lightnings on a webserver. The server is reachable as a normal website based on the LAMP method. The project reached a stadium which should satisfy a “proof of concept”, however, the product is far from complete, as it lacks the necessary algorithms needed for proper data computation. The current system only uses Raspberry pi, but it is theoretically possible to introduce other hardware to the system, but the current developed product does not support such functionality. / I den här rapporten föreslår vi ett blixtlokaliseringssystem kapabelt att varna lokal befolkningen om inkommande blixtväder med hjälp av en kombination av sensorn AS3935 och enchipsdatorn Raspberry Pi, i ett försök att skapa en produkt som är billig, mobil och användarvänlig. Systemet består av ett nät av sensorer som registrerar och rapporterar blixtaktivitet på en webbserver. Servern är nåbar som en vanlig hemsida som är byggd enligt LAMP metoden. Projektet har nått ett stadium som borde uppnå kraven för ett ”bevis av ett koncept”, men produkten är långt ifrån färdig, då den saknar de nödvändiga algoritmerna som krävs för ordentlig databehandling. Det nuvarande systemet använder sig enbart av Rasberry Pi:s, men i teorin vore det fullt möjligt att introducera ny hårdvara i nätet, men den nuvarande produkten stöder inte sådan funktionalitet.
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ZigBee-based climate measurement system for thermal comfort in traffic busses / ZigBee-baserat mätsystem för termisk komfort i bussarAlmosawi, Talib, Karanta, George January 2021 (has links)
This thesis describes the work process two (WP2) of a project led by the traffic administration in Stockholm to achieve the passengers' thermal comfort in traffic buses. The purpose of this thesis is to design and implement a measurement system comprised in eight measurement position in a bus. Each position is able to transmit data using a wireless communication protocol, with a central unit collecting all the transmitted data taking into consideration the accuracy of the measurements and filtering out the incorrect data. In order to accomplish this, a literature study is conducted investigating different measurement methods for different parameters, different communication protocols were analysed as well to determine an appropriate communication protocol suitable for climate measurement in a bus environment with passengers present on board. The output of the HVAC system is also required to help the traffic administration demonstrate the results of adjusting the temperature in the bus to reach the thermal comfort and how it led to saving energy. The system incorporates ZigBee , ESP32 microcontroller in the sender positions and a Raspberry pi operating as a central unit to collect data and store it in a file system providing an accurate data that will help the traffic administration achieve their goals. Unfortunately, there were some diffculties accessing CAN system data to provide the output of the HVAC system. / Detta examensarbete beskriver arbetsprocess två i ett projekt som leds av trafikförvaltningen i Stockholm för att uppnå termiska komfort för passagerare i busstrafik. Syftet med detta examensarbete är att utforma och implementera ett mätsystem bestående av åtta positioner i en buss. Varje position kan överföra data med hjälp av ett trådlöst kommunikationsprotokoll, en central enhet samlar in all data med hänsyn till mätningens noggrannhet och filtrering av felaktig data. För att uppnå detta utfördes en litteraturstudie för att undersöka mätningsmetoder för de olika parametrar. Olika kommunikationsprotokoll undersöktes för att bestämma en lämplig kommunikationsprotkoll för ett mätsystem som mäter klimat i bussar med passagerare ombord. Uteffekten av HVAC-systemet krävs också för att hjälpa trafikförvaltningen att bestämma fördelarna med att justera temperaturen i bussen för att nå den termiska komforten och hur den ledde till att spara energi. Systemet inkorporerar kommunikaitonsprotokollet ZigBee, ESP32-mikrokontroller i avsändarpositionerna och en Raspberry pi som fungerade som en central enhet för att samla in data och lagra det i ett filsystem med korrekta data som hjälper trafikförvaltningen att uppnå sina mål. Svårigheter uppstod med att få tillgång till CAN-system data för uteffekten av HVAC-systemet.
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Individual differences and stress reactions as predictors of performance in pilot traineesMalone, LaToya D. January 1900 (has links)
Master of Science / Department of Psychology / Ronald G. Downey / Firmly rooted in positive psychology, this study attempted to look beyond discovering the direction or shape of the stress-performance relationship and sought to instead determine the role of personality in this relationship. Although we were unable to test for moderation effects due to multicollinearity issues, we did discover that positive personality characteristics were a significant predictor of performance—even after controlling for experience and self-perceived stress. Interestingly, this relationship occurred in an opposite direction than expected in that higher levels of positive personality characteristics were predictive of lower performance ratings.
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Caractérisation et optimisation d'un réacteur pour l'ingénierie tissulaire 3DDubois, Justin January 2011 (has links)
Toward the objective to create or to replace impaired tissues, it is essential to establish a culture process allowing tissue growth in vitro . The Petri dish culture or the traditional 2D culture has only a limited potential, mainly caused by a poor oxygen mass transfer to feed larger tissue constructs. In this project, an autonomous and complete bioprocess has been built to fullfill these needs. The developed reactor is versatile because many cell culture chamber designs can be connected to it. Two proportional-integral algorithms (PI) can control the dissolved oxygen concentration and the pH. The pressure, the temperature and mass flow rate are recorded in real time. An actuator allows mimicking the cardiac output flow. In this mémoire , it will be demonstrated how the reactor has been optimized to reduce the risk of bioburden. Also, the procedures to develop the control tools of the PI algorithm will be detailed. To characterize the reactor, a RTD study will be presented. To characterize the cell culture chamber, a permeability analysis using fluorescent microscopy and magnetic resonance imaging (MRI) will be exposed. Finally, two cell culture chamber designs to orient microvessel formation have been tested and these results will be presented.
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A multiple-input single ended primary inductor converter for modular micro-grids with hybrid low-power sourcesZhao, Ruichen 28 October 2010 (has links)
This thesis studies a multiple-input single ended primary inductor converter (MI SEPIC) topology. The configuration allows the integration of different low-power distributed generation sources, such as individual photovoltaic modules, fuel cells, and small residential wind generators, into a common dc main bus. The current source interface allows the integration of all types of sources without the addition of filters; sources that require a nearly constant input current, such as fuel cells. In addition to discussing the circuit’s main models and operation, the thesis evaluates the stability under a decentralized PI control scheme through small signal analysis. The analysis is verified with simulations and experiments with prototypes. A derived circuit topology, the isolated MI SEPIC, is also explored here. In addition, a nonlinear control scheme, Lyapunov-based control, is implemented to stabilize an MI SEPIC. / text
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