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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.
221

Effiziente Mehrkernarchitektur für eingebettete Java-Bytecode-Prozessoren

Zabel, Martin 16 December 2011 (has links)
Die Java-Plattform bietet viele Vorteile für die schnelle Entwicklung komplexer Software. Für die Ausführung des Java-Bytecodes auf eingebetteten Systemen eignen sich insbesondere Java-(Bytecode)-Prozessoren, die den Java-Bytecode als nativen Befehlssatz unterstützen. Die vorliegende Arbeit untersucht detailliert die Gestaltung einer Mehrkernarchitektur für Java-Prozessoren zur effizienten Nutzung der auf Thread-Ebene ohnehin vorhandenen Parallelität eines Java-Programms. Für die Funktionalitäts- und Leistungsbewertung eines Prototyps wird eine eigene Trace-Architektur eingesetzt. Es wird eine hohe Leistungssteigerung bei nur geringem zusätzlichem Hardwareaufwand erzielt sowie eine höhere Leistung als bekannte alternative Ansätze erreicht.
222

Integrated wireless sensor system for efficient pre-fall detection

Tiwari, Nikhil 13 April 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The life expectancy of humans in today's era have increased to a very large extent due to the advancement of medical science and technology. The research in medical science has largely been focused towards developing methods and medicines to cure a patient after a diagnosis of an ailment. It is crucial to maintain the quality of life and health of the patient. It is of most importance to provide a healthy life to the elderly as this particular demographic is the most severely affected by health issues, which make them vulnerable to accidents, thus lowering their independence and quality of life. Due to the old age, most of the people become weak and inefficient in carrying their weight, this increases the probability of falling when moving around. This research of iterative nature focuses on developing a device which works as a preventive measure to reduce the damage due to a fall. The research critically evaluates the best approach for the design of the Pre-Fall detection system. In this work, we develop two wearable Pre-Fall detection system with reduced hardware and practical design. One which provides the capability of logging the data on an SD card in CSV format so that the data can be analyzed, and second, capability to connect to the Internet through Wifi. In this work, data from multiple accelerometers attached at different locations of the body are analyzed in Matlab to find the optimum number of sensors and the best suitable position on the body that gives the optimum result. In this work, a strict set of considerations are followed to develop a flexible, practical and robust prototype which can be augmented with different sensors without changing the fundamental design in order to further advance the research. The performance of the system to distinguish between fall and non-fall is improved by selecting and developing the most suitable way of calculating the body orientation. The different ways of calculating the orientation of the body are scrutinized and realized to compare the performance using the hardware. To reduce the number of false positives, the system considers the magnitude and the orientation to make a decision.
223

Design and Implementation of Energy Usage Monitoring and Control Systems Using Modular IIOT Framework

Chheta, Monil Vallabhbhai 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / This project aims to develop a cloud-based platform that integrates sensors with business intelligence for real-time energy management at the plant level. It provides facility managers, an energy management platform that allows them to monitor equipment and plant-level energy consumption remotely, receive a warning, identify energy loss due to malfunction, present options with quantifiable effects for decision-making, and take actions, and assess the outcomes. The objectives consist of: 1. Developing a generic platform for the monitoring energy consumption of industrial equipment using sensors 2. Control the connected equipment using an actuator 3. Integrating hardware, cloud, and application algorithms into the platform 4. Validating the system using an Energy Consumption Forecast scenario A Demo station was created for testing the system. The demo station consists of equip- ment such as air compressor, motor and light bulb. The current usage of these equipment is measured using current sensors. Apart from current sensors, temperature sensor, pres- sure sensor and CO2 sensor were also used. Current consumption of these equipment was measured over a couple of days. The control system was tested randomly by turning on equipment at random times. Turning on the equipment resulted in current consumption which ensured that the system is running. Thus, the system worked as expected and user could monitor and control the connected equipment remotely.
224

Systém pro autonomní řízení modelu autíčka na závodní dráze / System for Autonomous Navigation of Toy Car on a Race Track

Steingart, Viktor Unknown Date (has links)
This thesis deals with the design and implementation of a self-driving model race car that is intended to participate at NXP Cup race. First of all, the attention is given to the selection of a suitable platform, which will be used for the implementation of a motion control algorithm that enables autonomous navigation of the autonomous model race car along a specified track. Then, the details of motion control algorithm design and its implementation aspects are explained.  Also, the design of an obstacle detection system is presented. Finally, the work is concluded with presentation of various experiments with the implemented self-driving control algorithm and its evaluation.
225

Energy harvesting from ambient WiFi energy : A method of harvesting and measuring ambient WiFi energy

Fofana, Alpha, Mossberg, Carl January 2019 (has links)
The aim of this thesis was to investigate the question of how to harvest RF energy and if we can harvest enough RF energy for it to be useful in an application. It is aimed towards sensor node applications, commonly used in a typical office environment. The WiFi band was chosen since it is omnipresent in the same environment. With the current development within wireless technology and the IoT domain the demand for low power electronic applications has increased and one of the challenges is to find efficient and sustainable ways of powering these types of devices.The best possible theoretical power content was initially calculated followed by measurements in an office. A circuit was designed containing an impedance matching network and rectifier. A measurement application was constructed using a microcontroller. Measurements were made in an office environment and the maximum harvested energy over 24 hours was 350 mJ. The energy was stored in a supercapacitor and is estimated to be enough to power a low energy sensor for about 30 seconds. A large part of the thesis is devoted to impedance matching involving calculating, simulating and experimenting to get a good result. / Med den nuvarande utvecklingen inom trådlös teknik och IoT-domänen har efterfrågan på elektroniska applikationer med låg effekt ökat och en av utmaningarna är att hitta effektiva och hållbara sätt att driva dessa typer av enheter. Syftet med detta projekt var att undersöka frågan hur vi skördar radiovågsenergi och kan vi skörda tillräckligt mycket med energi för att den ska vara användbar i en applikation. I ett typiskt kontor finns fler källor till radiovågor, däribland WiFi som antas ha en hög nyttjandegrad. Projektet valde att inrikta sig på WiFi bandet och undersöka om det går att utvinna tillräckligt med energi där.Projektet strävade efter att leverera en färdig produkt med alla ingående delar, en antenn, en likriktare, en lagringsenhet och ett matchningsnätverk för att anpassa antenn och likriktare till varandra. För att undersöka hur mycket energi som finns att skörda gjordes först beräkningar och sedan mätningar i bland annat ett typiskt kontor. Det konstaterades att det rör sig om väldigt låga nivåer och betonas att de apparater som använder WiFi klarar av att känna av signaler som är långt mycket lägre än de som krävs för att kunna utvinna energi. Detta innebär alltså att apparaterna kan kommunicera felfritt samtidigt som energiinnehållet är så lågt att det inte går att utvinna någon energi.Projektet ägnar stor del åt att optimera den impedansmatchning som måste ske mellan antenn och likriktare för att största möjliga effektutbyte ska kunna ske. Basen är ett kretskort med ett typiskt impedansnätverk och genom beräkningar, simuleringar och experiment tas en prototyp fram. För att kunna analysera resultaten används en mikrokontroller som tar de analoga värdena, omvandlar dem till digitala och skickar dem till en PC för analys.Mätningar gjordes i en kontorsmiljö och den maximala mängden energi som gick att utvinna var 350 mJ på 24 timmar. Energin lagrades i en superkondensator och bedöms vara tillräcklig för att driva en lågenergisensor i ca 30 sekunder.
226

Evaluating LoRa Physical as a Radio Link Technology for use in a Remote-Controlled Electric Switch System for a Network Bridge Radio-Node

Aden Hassan, Abdullahi, Karlsson Källqvist, Rasmus January 2019 (has links)
This report explores the design of a system for remotely switching electronics on and off within a range of at least 15 km, to be used with battery driven radio nodes for outdoor Wi-Fi network bridging. The application of the network bridges are connecting to remote networks, should Internet infrastructure fail during an emergency.The problem statement for the report was “What is a suitable radio link technology for use in a remote controlled electrical switch system and how should it best be put to use?” To answer the question, delimitation was done to exploring Low Power Wide Area Network (LPWAN) link technologies, due to their prior use within power constrained devices.Long Range-radio, abbreviated LoRa, is a LPWAN radio modulation technique and was determined to be a good candidate as a suitable link technology for the remote electrical switch system. The range of LoRa is achieved by drastically lowering the data rate of the transmission, and is suitable for battery-powered or energy harvesting devices such as those found in the field of Internet of Things.A LoRa-based transmitter and receiver pair was implemented, and measured to have a packet delivery ratio of over 95% at a distance of 2 km, measured between two bridges. Data at further distances could not be accurately determined, because of the LoRa transceiver giving faulty readings.No conclusion could be made about the suitability for using a LoRa based system to solve the problem, partially due to an improper method for testing the radio performance was used, and partially due to an inconclusive measurement result. / Denna rapport utforskar designen av ett system för att fjärrstyrt slå på eller av elektronik över ett avstånd på minst 15 km, för att användas med batteridrivna radionoder för nätverksbryggning utomhus med Wi-Fi. Tillämpningsområdet för nätverksbryggorna är att koppla samman avlägsna nätverk, om Internetinfrastruktur skulle sluta fungera vid en nödsituation.Problemställningen för rapporten var ”Vad är en lämplig radiolänksteknik att använda i ett fjärrstyrt elektriskt strömbrytarsystem, och hur ska det bäst brukas?”. För att svara på frågan gjordes en avgränsning att utforska Low Power Wide Area Network (LPWAN)-länktekniker, på grund av deras tidigare användning inom effektbegränsade enheter.Long Range-radio, förkortat LoRa, är en radiomodulationsteknik som används för att skicka data över långa avstånd med energibegränsade enheter. LoRa:s räckvidd uppnås genom att drastiskt sänka datatakten, och lämpar sig för bruk i batteridrivna eller energiskördande enheter, likt de som återfinns inom fältet Internet of Things.Ett LoRa-baserat sändaroch mottagarpar implementerades, och uppmättes till att ha en paketlevereringsmängd på över 95% vid ett avstånd på 2 km, mätt mellan två broar. Data vid större avstånd kunde inte bli bestämt noggrant, eftersom LoRa transceivern gav felaktiga avläsningar. Ingen slutsats kunde göras för lämpligheten för att använda ett LoRa-baserat system för att lösa problemet, delvist för att en olämplig metod för att testa radions prestanda använts, och delvist på grund av ett ofullständigt mätresultat.
227

Real Time Measurement of Dirt Pick-up by a Robotic Vacuum Cleaner using Light Sensing Technology

Tina Monteiro, Shelsea January 2018 (has links)
Domestic chores are one of the most tedious and time consuming tasks in a person’s life. A lot of time can be saved and put to better use if these tasks can be automated. One such chore is the routine task of vacuuming the house every day. Robotic vacuum cleaners that clean the house are thus one of the most widely used domestic robots. These robots have the ability to clean the entire house almost autonomously with little or no human intervention. However, most of these robots do not have a system to report the real-time pick up of dirt which can be useful to the user in knowing which parts of his house are dirty and maybe investigate the reason behind it. This information can be useful to the robot as well in determining efficient cleaning patterns based on the dirt localization in the house. In this thesis a prototype was developed to measure the real-time pick-up of dirt by a robotic vacuum cleaner. It uses light sensing technology to measure the amount of dirt picked up and can thus be used to glean which parts of the house are dirtier than the others. The signals can also potentially be used to understand the size of the dirt picked up by the robotic vacuum cleaner. Research was done to investigate the different sensing technologies that can be used and to select the appropriate one. The system was tested and conclusions were made regarding its performance. Additional functions that can be implemented and improvements that can be made have also been suggested as future work. / Att städa hemmet är en av de mest tråkiga och tidskrävande uppgifterna i en persons liv. Mycket tid kan sparas och användas bättre om dessa uppgifter kan automatiseras. Robotdammsugare som städar golvet i hemmet är en av de mest använda inhemska robotarna, då dessa robotar har möjlighet att rengöra hela huset nästan autonomt med liten eller ingen mänsklig intervention. De flesta av dessa robotar har dock inte ett system för att rapportera realtidsupphämtning av smuts som kan vara användbart, då användaren kan få reda på vilka delar av huset som är smutsiga och då ha möjlighet att undersöka orsaken bakom. Denna information kan också vara användbart för roboten för att bestämma effektiva rengöringsmönster baserat på lokalisering av smuts i huset. I denna avhandling utvecklades en prototyp för att mäta upptagning av smuts i realtid av en robotdammsugare. Den använder IR-teknik för att mäta mängden smuts som hämtas upp och kan därmed använda informationen för att avgöra vilka delar av huset som är smutsigare än andra. Signalerna kan också potentiellt användas för att förstå storleken på smuts som tas upp. Forskning av olika tekniker utfördes för att kunna välja den mest lämpliga. Systemet testades därefter och slutsatser gjordes avseende dess prestanda. Ytterligare utredningar och förbättringar som kan genomföras har också föreslagits som framtida arbete.
228

Embedded System Design for Pill Boxes with The Low Power Electronic Paper Display

Kamran, Ali January 2017 (has links)
The rapid development of technology in the health-care sector has led to the discovery of many new illnesses and improved treatments that were not possible earlier. However, many treatments and medicines for a specific disease often come with several side effects. The accuracy in treatments with an optimal result on specified targets is therefore desired with minimum side effects. This requires that the production and the usage processes should be precise. The scope of this study is not about the medicine production phase but rather on managing a medicine schedule. How many times a medicine should be taken in a day is strongly related to its dosage and following a precise timing plays a crucial role in the individual’s health. As a solution, a pill box based on a low power display (Electronic Paper Display, EPD) together with an embedded system has been introduced by the project owner (Victrix AB, Stockholm) .The pill box should have some different functions like alarms, data logging and wireless reporting. Different types of alarms including ringtone, vibration and voice recording/playing are required as well. To be able to trace the already planned timing for taking medicines, system will be able to save and report history of the past 100 days. Since every single idea for solving different parts of the problem should be tested in real system, a Quantitative Research based on experiments be used and the best possible solution be selected and implemented in the project. Studying technical material and also related works besides analyzing generated data after each experiment were a useful tool for the system integration in this work. As the result, a pill box based on an embedded system was designed and integrated successfully. A hardware platform, in form of a prototype system based on an ARM microcontroller and a compatible embedded software have been designed, improved and tested successfully and are available. At the end of this work, the low power E-paper display works properly, alarms can be set and activated, data can be saved and also sent wirelessly. Basically, the result of this project shows how an embedded system can be specialized and programmed to be able to interact with patients and e.g. nurses in order to make a stable and continuous connection between them. Most of determined goals have been achieved and some of them be changed and modified during the work. Also a few additional functions and improvements be suggested as future work.
229

Wireless electromyogram system

Dunca, Andreas, Nguyen, Hoang Anh Quoc January 2020 (has links)
Venous thromboembolism (VTE) is one of the most common cardiovascular diseases. KTH and its academic and industrial partners intend to develop a system to combat VTE by forcing movements of inactive muscles. An important part of this system is a unit that can sense muscular activity over time. Electromyography (EMG) is used to measure the activation potential of muscles. The goal of this thesis is to develop an EMG device that can measure bioelectric signals and convey this data to other devices. This thesis is mainly an exploration to identify the potential solution and more work is needed to develop the required system. The EMG device must be small, modular, battery powered and be able to communicate wirelessly with other devices. A functioning EMG system requires an appropriate amplification for the result to be legible and requires extensive filtering as well as detailed circuit board design to eliminate noise or interference that can affect the result.This project utilized a top down approach. An architecture of the EMG system was made and broken down into functional blocks. Each block was implemented separately and the whole solution was tested experimentally to ensure that all the specifications were fulfilled. To validate the EMG device, a series of reference images were used together with directly observing the correlation between muscle activation and its signal with an oscilloscope.The result was a fully functional EMG device that consisted of two PCB: a PCB with EMG circuitry (analog circuit) and a PCB with digital processing for communication (digital circuit). The EMG results were consistent between test subjects and could easily be correlated to muscle movement and force. The reference images indicated that it was functioning as intended. There was still 50 Hz common mode noise present in the EMG device which could have been due to its wide bandwidth and poor low frequency properties.The goals and requirements were fulfilled: a fully functional wireless, modular, small and battery driven EMG device was developed. The noise level of the EMG could have been lower and would need some further improvements. An integrated battery could be implemented to eliminate the need for users to provide a battery. An app could be developed in tandem with the EMG device, with friendly user interface, for healthcare personnel.The thesis workers strived to minimize the number of used components and power consumption. All components were RoHS certified and discarded components were collected for proper waste management. Energy consumption could have been further minimized in the digital PCB by implementing sleep mode and a watchdog timer. This thesis strived to implement as much of the 17 global sustainability goals set by the United Nations (UN). In conclusion, the main sustainability goal of this thesis was “3 – Good Health and well-being”. Other sustainability goals were “12 – Responsible consumption and production”, “13 – Climate action”, “15 – Life on land” were deemed to have been considered in this thesis. / Venös tromboemboli (VTE) är en av de vanligaste kardiovaskulära sjukdomarna. KTH och dess akademiska och industriella partner avser att utveckla ett system med uppdrag att bekämpa VTE genom att stimulera inaktiva muskler. Elektromyografi (EMG) används för att mäta musklernas aktiveringspotential. Syftet med denna avhandling är att utveckla en EMG-enhet som kan mäta bioelektriska signaler och överföra denna data till andra enheter. Ett fungerande EMG system kräver en lämplig förstärkning för att resultatet ska vara läsbart och kräver filtrering samt utförlig kretskortdesign för att eliminera brus/störningar som kan påverka resultatet negativt.Projektet använde en Top-Down strategi. En arkitektur av EMG-systemet genomfördes och sedan delades upp i funktionella block. Varje block implementerades separat och hela lösningen testades experimentellt för att säkerställa att alla specifikationer uppfylldes. För att validera EMG- enheten användes referensbilder tillsammans med att direkt observera sambandet mellan muskelaktivering och dess signal via ett oscilloskop.Resultatet var en helt funktionell EMG-enhet som bestod av två PCB: en PCB med EMG funktionalitet (analog krets) och en PCB med digital processering för kommunikation (digital krets). EMG mätningarna var konsistenta mellan testpersoner och kunde lätt korreleras med muskelrörelse och spänningskraft. Referensbilderna indikerade att den fungerade som avsedd. Det fanns fortfarande 50 Hz common mode brus i EMG-enheten, vilket kan ha orsakas av dess breda bandbredd och dåliga lågfrekvensegenskaper.Målen och kraven uppfylldes: en fullt funktionell trådlös, modulär, liten och batteridriven EMG- enhet. Brusnivån för EMG kunde ha varit lägre och skulle behöva ytterligare förbättringar. Ett integrerat batteri kunde implementeras för att eliminera användarnas behov av att tillhandahålla ett batteri. En applikation kunde ha utvecklats för EMG-enheten, med ett användarvänligt användargränssnitt, för vårdpersonal.Examensarbetarna strävade efter att minimera användning av komponenter och strömförbrukning under arbetsprocessen. Alla komponenter var RoHS-certifierade och kasserade komponenter insamlades för korrekt avfallshantering. Energiförbrukning kunde ha minimerats ytterligare i det digitala kretskortet genom att implementera sleep mode och en watchdog timer. I detta examensarbete var det önskvärt att implemnetera de 17 globala hållbarhetsmålen uppsatta av FN (Förenta Nationerna). Sammanfattningsvis uppfylldes huvudsakligen “3 – Good Health and well-being”. Hållbarhetsmålen ”12 - Ansvarig konsumtion och produktion”, ”13 – Klimatåtgärder”, ”15 - Liv på land” anses även att ha beaktas i denna avhandling.
230

Evaluation of FPGA Partial Reconfiguration : for real-time Vision applications

Guo, Guanghao January 2020 (has links)
The usage of programmable logic resources in Field Programmable Gate Arrays, also known as FPGAs, has increased a lot recently due to the complexity of the algorithms, especially for some computer vision algorithms. Due to this reason, sometimes the hardware resources in the FPGA are not sufficient. Partial reconfiguration provides us with the possibility to solve this problem. Partial reconfiguration is a technique that can be used to reconfigure specific parts of the FPGA during run-time. By using this technique, we can reduce the need for programmable logic resources. This master thesis project aims to design a software framework for partial reconfiguration that can load a set of processing components/algorithms (e.g. object detection, optical flow, Harris-Corner detection etc) in the FPGA area without affecting real-time static components such as camera capture, basic image filtering and colour conversion which are continuously running. Partial reconfiguration has been applied to two different video processing pipelines, a direct streaming architecture and a frame buffer streaming architecture respectively. The result shows that reconfiguration time is predictable which depends on the partial bitstream size, and that partial reconfiguration can be used in real-time applications taking the partial bitstream size and the frequency to switch the partial bitstreams into account. / Användningen av programmerbara logiska resurser i Field Programmable Gate Arrayer, även känd som FPGA:er, har ökat mycket nyligen på grund av komplexiteten hos algoritmerna, speciellt för vissa datorvisningsalgoritmer. På grund av detta är det ibland inte tillräckligt med hårdvaruresurser i FPGA:n. Partiell omkonfiguration ger oss möjlighet att lösa detta problem. Partiell omkonfigurering är en teknik som kan användas för att omkonfigurera specifika delar av FPGA:n under körtid. Genom att använda denna teknik kan vi minska behovet av programmerbara logiska resurser. Det här mastersprojektet syftar till att utforma ett programvaru-ramverk för partiell omkonfiguration som kan ladda en uppsättning processkomponenter / algoritmer (t.ex. objektdetektering, optiskt flöde, Harris-Corner detection etc) i FPGA- området utan att påverka statiska realtids-komponenter såsom kamerafångst, grundläggande bildfiltrering och färgkonvertering som körs kontinuerligt. Partiell omkonfiguration har tillämpats på två olika videoprocessnings-pipelines, en direkt-strömmande respektive en rambuffert-strömmande arkitektur. Resultatet visar att omkonfigurationstiden är förutsägbar och att partiell omkonfiguration kan användas i realtids-tillämpningar.

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