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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.
41

DESIGN AND DEVELOPMENT OF A FALL DETECTION DEVICE WITH INFRARED RECEIVING CAPABILITIES

Ramzi, Ammari 24 August 2011 (has links)
No description available.
42

Operating systems for resource constraint Internet of Things devices: An evaluation

Elvstam, Andreas, Nordahl, Daniel January 2016 (has links)
Internet of Things (IoT) är ett område under omfattande utveckling, både vad det gäller hårdvara och mjukvara. När det gäller hårdvaruplattformar för IoT enheter finns det platt-formar som är kraftfulla nog att exekvera ett reguljärt OS som t.ex. Linux. Andra hårdvaru-plattformar är inte tillräckligt kraftfulla för att exekvera reguljära OS och för dessa plattformar finns ett behov av resurseffektiva små IoT OS. Dessa resurssnåla OS behöver kunna hantera många av de funktioner som reguljära OS erbjuder, men på ett betydligt mer effektivt sätt.Det har under de senaste åren släppts en uppsjö av olika IoT OS för resurssnåla enheter och därför är syftet med denna rapport en utvärdering av IoT OS för strömsnåla resurssvaga IoT enheter. Utvärdering genomförs på IoT OS:en Contiki, mbed, RIOT och Zephyr. Målet med utvärderingen är att fastställa viktiga egenskaper för ett IoT OS för strömsnåla resurssvaga IoT enheter, och att belysa svårigheter och erfarenheter relaterade till konstruktionsprocessen av en prototyp för IoT enheter. Utvärderingen genomfördes genom att samla in fyra olika typer av data relaterade till IoT OS:en, och sedan utvärdera denna data med hjälp av en kriteriebaserad utvärderingsmetod.Utvärderingen resulterade i en lista av sex viktiga egenskaper för små resurs snåla IoT operativsystem. Dess resultat belyser även svårigheter och erfarenheter som framkommit under byggprocessen av prototyperna baserade på IoT OS:en.Slutsatsen av denna rapport bidrar med erfarenheter från byggning av prototyper IoT OS för resurssnåla enheter, samt ett utvärderingsresultat för IoT OS:en med hänsyn till de sex viktiga IoT OS egenskaperna. / The Internet of Things (IoT) is a large and rapidly expanding area with regards to both hardware platforms and software. When it comes to hardware platforms for the IoT some are more powerful and able to run a traditional OS like Linux, while other platforms are too constraint to do so. To ease the development within the IoT area an appropriate IoT OS is needed for these constrained hardware platforms, which can handle most of the functionality a traditional OS offer.Therefore, we evaluate IoT OSs targeted for low performance battery powered devices. In this thesis Contiki, mbed, RIOT and Zephyr are evaluated. The aim of this evaluation is to determine important IoT OS characteristics for resource constrained devices, and to highlight difficulties and experiences related to the building process of prototypes for such IoT devices.The evaluation of the IoT OSs were conducted on four types of data with regards to several measurable OS characteristics according to a criteria based evaluation method.The evaluation resulted in a list of six IoT OS characteristics important for wireless, resource constrained and battery powered devices. Furthermore the evaluation highlights potential setbacks during the building process of a prototype system for such devices and it also explains what experiences that can be gained.The conclusion of this thesis contributes with experience related to IoT OS prototype construction and also an evaluation result with respect to the six IoT OS characteristics for constraint battery driven devices.
43

Evaluation of theft detection for smart beehives : Development of a Bluetooth-based approach. / Stöld-detektion för smarta bikupor : Utveckling av bluetooth-baserad lösning

Björck, Elin January 2024 (has links)
Beekeeping is an ancient activity that has been practised for thousands of years. Bees and other pollinators are important to food security. Sources indicate that bee-hive theft is on the rise in Sweden. In this report, different alternatives to beehive theft detection are explored. Possible solutions are found by looking at theft detec-tion in general and for beehives in particular. This work describes the different types of theft that beehives are subjected to. Suggested solutions for theft detection are based on activities that might be related to the different types of theft. One of the solutions is implemented and tested. An anti-theft system for cars inspires the solution, and it is partially chosen because it seems novel to the field of beehive theft detection. In the implemented solution, one external unit is keeping track of all the hives using regular check-ins via Bluetooth. Absent check-ins could indicate that a hive is missing. Through testing, it is shown that there is room for improvement inthe implementation, both when it comes to energy consumption and when it detects theft. Deployment costs could be low for situations with a large enough number of beehives at the same place, if the hives are assumed to be smart, this solution only requires one external unit to be added, whereas other solutions might require extra sensors in every hive. For a smaller number of hives, it should be more cost-effectiveto add some sensor that can detect that the hive is manipulated.
44

Low-Power Wireless Sensor Node with Edge Computing for Pig Behavior Classifications

Xu, Yuezhong 25 April 2024 (has links)
A wireless sensor node (WSN) system, capable of sensing animal motion and transmitting motion data wirelessly, is an effective and efficient way to monitor pigs' activity. However, the raw sensor data sampling and transmission consumes lots of power such that WSNs' battery have to be frequently charged or replaced. The proposed work solves this issue through WSN edge computing solution, in which a Random Forest Classifier (RFC) is trained and implemented into WSNs. The implementation of RFC on WSNs does not save power, but the RFC predicts animal behavior such that WSNs can adaptively adjust the data sampling frequency to reduce power consumption. In addition, WSNs can transmit less data by sending RFC predictions instead of raw sensor data to save power. The proposed RFC classifies common animal activities: eating, drinking, laying, standing, and walking with a F-1 score of 93%. The WSN power consumption is reduced by 25% with edge computing intelligence, compare to WSN power that samples and transmits raw sensor data periodically at 10 Hz. / Master of Science / A wireless sensor node (WSN) system that detects animal movement and wirelessly transmits this data is a valuable tool for monitoring pigs' activity. However, the process of sampling and transmitting raw sensor data consumes a significant amount of power, leading to frequent recharging or replacement of WSN batteries. To address this issue, our proposed solution integrates edge computing into WSNs, utilizing a Random Forest Classifier (RFC). The RFC is trained and deployed within the WSNs to predict animal behavior, allowing for adaptive adjustment of data sampling frequency to reduce power consumption. Additionally, by transmitting RFC predictions instead of raw sensor data, WSNs can conserve power by transmitting less data. Our RFC can accurately classify common animal activities, such as eating, drinking, laying, standing, and walking, achieving an F-1 score of 93%. With the integration of edge computing intelligence, WSN power consumption is reduced by 25% compared to traditional WSNs that periodically sample and transmit raw sensor data at 10 Hz.
45

Internet of Things & Kommunikationsprotokoll / Internet of Things & Communication Protocol

Sabel, Ida January 2015 (has links)
Genom att studera olika kommunikationsprotokoll kunna svara på vad det är som gör att ett visst protokoll är bäst anpassat för att användas mellan mobila enheter och IoT-enheter. I arbetet användes en kvalitativ litteraturstudie för att ge en grundlig teoretisk bakgrund samt en experimentell studie där ett par teorier undersökts ifall de stämmer med resultaten ifrån verkligheten. De fem faktorerna kompatibilitet, batteritid, frekvens, räckvidd och tillförlitlighet undersöktes hos kommunikationsprotokollen Bluetooth Low Energy (BLE), Närfältskommunikation (NFC) och Wi-Fi. Dessa tre valdes eftersom de stöds av nyare mobila plattformar idag. Kommunikations-protokollen analyserades sedan gentemot olika användningsområden inom IoT, eftersom påståendet vad som är bäst anpassat beror på vad situationen kräver för egenskaper. En systemutvecklare som ska välja kommunikationsprotokoll till en IoT-tillämpning och läser denna rapport bör själv jämföra de olika protokollen mot varandra inom de fem faktorerna för att kunna avgöra vilket protokoll som passar bäst inom dennes situation. I arbetet utfördes endast experimentella studier på BLE på grund av begränsningar inom utrustningen. Ytterligare experiment inom NFC och Wi-Fi skulle ge ett bredare perspektiv med fler infallsvinklar. / By studying different communication protocols respond to what it is that makes a certain protocol best suited for use between mobile devices and IoT devices. This study used a qualitative literature study to create a proper theoretical background and an experimental study where two theories were investigated in whether they matched wih the results from the reality. The five factors compatibility, battery loss, frequency, range and reliability were investigated in the communication protocols Bluetooth Low Energy (BLE), Near field communication (NFC) and Wi-Fi, these three because they are supported by newer mobile platforms today. The communication protocols were then analysed against various uses in the IoT, since the claim what it is that makes it best suited depends on what the situation requires. A system developer that is about to select the communication protocol to use in an IoT application and reads this study should compare the different protocols to each other within the five factors to determine which protocol is best suited for his situation. This study only performed experimental studies on BLE because of limitations in the equipment. Additional experiments on NFC and Wi-Fi would provide a wider perspective.
46

Simulation multi-moteurs multi-niveaux pour la validation des spécifications système et optimisation de la consommation / Multi-engine multi-level simulation for system specification validation and power consumption optimization

Li, Fangyan 29 March 2016 (has links)
Ce travail vise la modélisation au niveau système, en langage SystemC-AMS, et la simulation d'un émetteur-récepteur au standard Bluetooth Low Energy (BLE). L'objectif est d'analyser la relation entre les performances, en termes de BER et la consommation d'énergie du transceiver. Le temps de simulation d’un tel système, à partir de cas d’étude (use case) réaliste, est un facteur clé pour le développement d’une telle plateforme. De plus, afin d’obtenir des résultats de simulation le plus précis possible, les modèles « haut niveau » doivent être raffinés à partir de modèles plus bas niveau où de mesure. L'approche dite Meet-in-the-Middle, associée à la méthode de modélisation équivalente en Bande Base (BBE, BaseBand Equivalent), a été choisie pour atteindre les deux conditions requises, à savoir temps de simulation « faible » et précision des résultats. Une simulation globale d'un système de BLE est obtenue en intégrant le modèle de l'émetteur-récepteur dans une plateforme existante développée en SystemC-TLM. La simulation est basée sur un système de communication de deux dispositifs BLE, en utilisant différents scénarios (différents cas d'utilisation de BLE). Dans un premier temps nous avons modélisé et validé chaque bloc d’un transceiver BT. Devant le temps de simulation prohibitif, les blocs RF sont réécrits en utilisant la méthodologie BB, puis raffinés afin de prendre en compte les non-linéarités qui vont impacter le couple consommation, BER. Chaque circuit (chaque modèle) est vérifié séparément, puis une première simulation système (point à point entre un émetteur et un récepteur) est effectuée / This work aims at system-level modelling a defined transceiver for Bluetooth Low energy (BLE) system using SystemC-AMS. The goal is to analyze the relationship between the transceiver performance and the accurate energy consumption. This requires the transceiver model contains system-level simulation speed and the low-level design block power consumption and other RF specifications. The Meet-in-the-Middle approach and the Baseband Equivalent method are chosen to achieve the two requirements above. A global simulation of a complete BLE system is achieved by integrating the transceiver model into a SystemC-TLM described BLE system model which contains the higher-than-PHY levels. The simulation is based on a two BLE devices communication system and is run with different BLE use cases. The transceiver Bit-Error-Rate and the energy estimation are obtained at the end of the simulation. First, we modelled and validated each block of a BT transceiver. In front of the prohibitive simulation time, the RF blocks are rewritten by using the BBE methodology, and then refined in order to take into account the non-linearities, which are going to impact the couple consumption, BER. Each circuit (each model) is separately verified, and then a first BLE system simulation (point-to-point between a transmitter and a receiver) has been executed. Finally, the BER is finally estimated. This platform fulfills our expectations, the simulation time is suitable and the results have been validated with the circuit measurement offered by Riviera Waves Company. Finally, two versions of the same transceiver architecture are modelled, simulated and compared
47

Message Classification Based Continuous Data Transmission for an E-health Embedded System

Sun, Jiuwu January 2019 (has links)
This thesis aims to develop an e-health embedded system with a real-time operating system (RTOS), which allows users to monitor their body condition, including heart rate and breath, through Bluetooth Low Energy (BLE). Meanwhile, the device is also able to provide guidance for breathing by simulating breathing according to given parameters. In practice, the system samples the heart rate every two milliseconds. To ensure reliability and validity, results are expected to be sent in realtime. However, numerous data cannot be transmitted directly without being processed. Otherwise, the system will crash, and hard faults will occur. A general idea to solve this problem is to classify messages into two categories based on the priority. One is urgent, and the other is unimportant. Two solutions are proposed, one using a unidirectional linked list, and the second using queues. Based on an ARM micro-controller, the e-health embedded system is designed and implemented successfully. The evaluation results show that the solution using a linked list is suitable for the system, while the solution using queues is unable to solve the problem. With the help of the message classification, the urgent messages can be timely transmitted with continuous data. / Avhandlingen syftar till att utveckla ett e-hälso-inbyggt system med ett realtidsoperativsystem (RTOS), som gör det möjligt för användare att övervaka sitt kroppstillstånd, inklusive hjärtfrekvens och andetag, genom Bluetooth Low Energy (BLE). Samtidigt kan enheten också ge vägledning för andning genom att simulera andning enligt givna parametrar. I praktiken samplar systemet hjärtfrekvensen varannan millisekund. För att säkerställa tillförlitlighet och giltighet bör resultaten skickas i realtid. Annars kraschar systemet och allvarliga fel uppstår. En allmän idé för att lösa detta problem är att klassificera meddelanden i två kategorier baserade på prioritering, en är brådskande och den andra är obetydlig. Två lösningar föreslås, en med hjälp av riktad länkad lista och en annan implementerad med hjälp av köer. Resultatmässigt, baserat på en ARM-mikrokontroller, är det inbyggda e-hälsosystemet framgångsrikt designat och konfigurerat. Lösningen med en länkad lista är lämplig för systemet, medan lösningen som implementeras med köer fortfarande inte kan lösa problemet. Med hjälp av meddelandeklassificeringen är de brådskande meddelandena inte ens försenade med kontinuerlig data.
48

En förenklad beslutsmodell av Real Time Locating System inom verkstadsindustrin : En fallstudie av tre produktionsenheter på företaget Scania / A simplified decision-making model of Real Time Locating System in the engineering industry : A case study of three production units at Scania

Idre, Andreas, Lindesten, Elin January 2018 (has links)
Under de senaste åren har intresset för att positionera objekt inomhus ökat tack vare den tilltagande trenden kring Internet of Things (IOT). I den tekniska världen återfinns ett flertal begrepp för inomhuspositionering, däribland Real Time Locating System (RTLS). RTLS främsta egenskap är att identifiera och lokalisera objekt inomhus, kvalitetssäkra processer, informationsutbyte mellan aktörer, alarmera om objekt rör sig utanför vissa gränser. Gemensamt är att det ska effektivisera processer i flödet. En verkstadsindustri, som Scania CV AB, karaktäriseras av maskiner, rörelse, buller, personal och material. Materialet som återfinns på Scania kan påverka RTLSteknologin. Det finns idag inte en dominerande teknik för inomhuspositionering därav att det har genererat i flertalet tekniker däribland UWB, RFID, IR, BLE, Wi-Fi. Rapportens frågeställningar är vilka utvärderingskriterier som styr valet av RTLSsystem och vilka av de här kriterierna är mer kritiska än andra? samt vilka tekniker kan användas i en verkstadsindustrin idag? För att besvara rapportens frågeställningar har ett kvalitativt förhållningssätt använts. Rapporten har använt fallstudie för att kunna svara på studiens frågeställningar. En kvalitativ ansats har använts med intervjuer och observationer som genomförande på produktionsenheterna. Tidigare forskning har legat till grund för utformningen av utvärderingskriterierna. Utvärderingskriterierna har i rapportens analysdel vägts in mot teknikens förutsättningar, omgivningens preferenser och mot det specifika behovet. Slutsatsen är att behovet och omgivningen är de två viktigaste elementen att beakta vid ett beslutsfattande av RTLS-system. I ett beslutsfattande är vissa kriterier mer kritiska än andra. Då behovet styr valet av teknik blir således samtliga tekniker användbara i en verkstadsindustri. Det finns dock ingen teknik som passar samtliga behov varför det således blir viktigt att välja en leverantör med bred produktportfölj som har möjlighet att erbjuda hybrider. / During the recent years the interest of positioning has increased due to the growing trend of Internet of Things (IoT). In the technical world there are several concepts for indoor positioning, among them Real Time Locating System (RTLS). RTLS main feature is to identify and locate objects indoors, to insure the quality of processes, to exchange information between stakeholder and to alert if items move beyond certain limits. Common is that it will streamline working processes. A engineering industry, such as Scania CV AB, is characterized by objects such as machines, motions, noise, personnel and materials. These objects found in Scania may affect the RTLS technology. There is currently no dominant indoor positioning technology on the market, thus there are many different technologies including UWB, RFID, IR, BLE and Wi-Fi. The problem definition of the thesis is therefore “What evaluation criteria are affecting the decision-making process when choosing RTLS and what criteria is more critical than the other?” and “Which technologies can be used in a engineering industry today?” To answer these problem definitions a qualitative research has been issued structured by a case study. Interviews and observations has been carried out as methods at the production units. The evaluation criteria are based on previous research. The criteria have been weighed against the technical conditions, the preferences of the environment and the specific use case. The conclusion is that the use case and the environment are the two most important elements to consider when deciding on a RTLS technology. In decision-making some criteria are more critical than others. As use case directs what technology should be used, all technologies are considered to be useful in a engineering industry. However there is no technology that fits all applications, thus it is important to choose a vendor that has a comprehensive product portfolio and one that enables hybrid solutions.
49

La cosmovisión mapuche de lo onírico representada en la poesía etnocultural femenina

Carrasco, Bladimir January 2008 (has links)
<p>El siguiente estudio tiene como finalidad revelar la presencia de la cosmovisión mapuche de lo onírico en la poesía etnocultural escrita por mujeres. La propuesta es que la función que los sueños cumplen dentro de la cultura y religiosidad mapuche está claramente reflejada en el dis-curso poético de las autoras investigadas. Las teorías que sustentan esta hipótesis defienden la estrecha relación que existe entre el texto litera-rio y la cultura en que éste ha sido generado. El estudio pretende, ade-más, identificar las distintas funciones de los sueños en la cultura pre-sentes en el corpus seleccionado, y de tal manera poder plasmar esta correspondencia.</p>
50

ColoroPhone : Design and implementaion of a distance measurement system for object detection

Ward, Jon Åge January 2018 (has links)
In this project, I have developed and built a new prototype of the ColoroPhone visual aid. This new prototype has sensors to measure the distance to objects in front of the wearer, which then communicates with a mobile application that generates sounds depending on the distance to the object. The user will hear this sound through bone-conducting headphones This addition to the ColoroPhone is intended to further enhance the assistance the device can offer. The current prototype is a functioning version and will be used in further research done by a group of psychologists, which will study how such devices affect users both on a biological and social level. They will also evaluate how to approach user training. The prototype in its current state have several segments that have considerable room for improvement in further development of the platform. Some of these improvements can be in form of better Bluetooth implementation, better or more sensors, or improvements in the current set of sensors regarding noise handling and data processing. This type of device can have large impact on the daily life for a large and growing amount of people across the world, as independence is a large factor in a persons feel of self-worth and long term psychological health.

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