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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

Movement behaviour of traditionally managed cattle in the Eastern Province of Zambia : investigations using two-dimensional motion sensors

Lubaba, Caesar Himbayi January 2011 (has links)
Two-dimensional (2-D) motion sensors are activity motion sensors that use electronic accelerometers to record the lying, standing and walking behaviour of animals. They were used in this study with the aim of monitoring and quantifying the movement behaviour of traditionally managed cattle in the context of improving animal health and production in rural sub-Saharan Africa. Improvements in animal health and production could be made if data can be automatically collected on large numbers of animals and over prolonged periods of time. This data can then be used by stakeholders in making management and disease control decisions. This study was designed to assess whether the 2-D motion sensors were suitable for use on traditionally managed cattle in Kasero and Makale, two veterinary camps in Petauke District, Eastern Province of Zambia. It further aimed to provide a baseline for future research on traditional cattle movement behaviour. The study was carried out in a region where trypanosomiasis and tick-borne diseases are endemic and low haemoglobin values are often associated with these and other parasitic infections. An assessment was made on the effect on cattle movement behaviour of a treatment directed against tsetse-transmitted (trypanosoma congolense (Savannah type), trypanosoma vivax and trypanosoma brucei), tick-transmitted (theileria parva, anaplasma spp. and babesia spp.) and pasture-transmitted pathogens of African cattle. A structured questionnaire on livestock ownership and management practices showed that cattle owners considered trypanosomiasis and theileriosis the main constraints to improved cattle health and production in their traditional crop-livestock mixed farming system. A baseline study was conducted in which haemoglobin values were measured in 432 cattle in the two areas. In each area, ten pairs of co-grazing cattle were selected on the basis of one high and one low haemoglobin value in each pair. The co-grazing pairs were age and sex matched. Each animal had a motion sensor placed on its hind leg, to continuously measure and record its activity for two weeks. There were significant differences in haemoglobin levels between the two camps with Makale having lower levels than Kasero. Baseline data indicated that a larger proportion of sampled animals in Makale had trypanosomiasis while those in Kasero had theileriosis. Molecular parasitological results showed that the proportion of animals sampled in Makale that had trypanosomiasis was greater (21.4% [95%CI: 16.4 – 27.1]) than that in Kasero (1.4% [95%CI: 0.5 – 4.1]). However, Kasero had a greater proportion of animals positive for theileriosis (25.6% [95%CI: 20.2 – 31.9]) than Makale (2.4% [95%CI: 1.0 – 5.2]). A total of 204 cattle were screened for a three week treatment study in Makale. From this number, 40 animals with low circulating haemoglobin levels (<8g/dl) were paired and investigated for differences in movement behaviour patterns between treated and non- treated cattle. Analysing the sensor data using principal components analysis (PCA) revealed that the treated animals (which had higher mean haemoglobin values at the end of the study) were clustered more closely on the score plots than the control animals (which had lower mean haemoglobin values). The numbers of steps taken by high haemoglobin cattle in both studies were significantly higher than the low haemoglobin cattle. This, coupled with the PCA results suggests an association between cattle haemoglobin levels and their movement patterns.
2

Evaluating the Effects of Public Postings on Energy Conservation Behavior at a Public University

Canisz, Eleni 08 1900 (has links)
This study evaluated the effects of public postings on energy conservation behavior at a public university, using a multiple baseline design across three settings; bathrooms break rooms, and conference rooms. The behavior of building occupants was recorded to assess the frequency at which those individuals would turn lights off upon exiting an unoccupied room. The independent variables implemented by experimenters (light-switch plate stickers and laminated signs) had little to no effects on cumulative instances of lights turned off however, the installation of motion sensor lights produced better results. Across all conditions, lights were turned off most frequently in conference rooms (65% of observations) followed by break rooms (9% of observations), and bathrooms (3% of observations).
3

High-response hydraulic linear drive with integrated motion sensor and digital valve control

Šimic, Marko, Herakovič, Niko 27 April 2016 (has links) (PDF)
Main purpose of the paper is to present high-response hydraulic linear drive, which is controlled with new digital piezo valve and where the new position transducer is integrated as a part of hydraulic cylinder. Hydraulic digital piezo valve with main static and dynamic characteristics as well as its functionality is presented in detail. The main static and dynamic characteristics of dygital piezo valve which influence directly on the linear drive performance are high resolution of the volume flow rate and high resposne of the valve. Beside valve characteristics the new integrated position transducer, the digital controller and control method, presented in the paper, have major impact on linear drive preformance. At the end of the paper the step response and position resolution of the hydraulic linear drive controlled with the new digital valve is compared with the results of reference hydraulic drive controlled with high response proportional valve.
4

Virtual lead-through robot programming : Programming virtual robot by demonstration

Boberg, Arvid January 2015 (has links)
This report describes the development of an application which allows a user to program a robot in a virtual environment by the use of hand motions and gestures. The application is inspired by the use of robot lead-through programming which is an easy and hands-on approach for programming robots, but instead of performing it online which creates loss in productivity the strength from offline programming where the user operates in a virtual environment is used as well. Thus, this is a method which saves on the economy and prevents contamination of the environment. To convey hand gesture information into the application which will be implemented for RobotStudio, a Kinect sensor is used for entering the data into the virtual environment. Similar work has been performed before where, by using hand movements, a physical robot’s movement can be manipulated, but for virtual robots not so much. The results could simplify the process of programming robots and supports the work towards Human-Robot Collaboration as it allows people to interact and communicate with robots, a major focus of this work. The application was developed in the programming language C# and has two different functions that interact with each other, one for the Kinect and its tracking and the other for installing the application in RobotStudio and implementing the calculated data into the robot. The Kinect’s functionality is utilized through three simple hand gestures to jog and create targets for the robot: open, closed and “lasso”. A prototype of this application was completed which through motions allowed the user to teach a virtual robot desired tasks by moving it to different positions and saving them by doing hand gestures. The prototype could be applied to both one-armed robots as well as to a two-armed robot such as ABB’s YuMi. The robot's orientation while running was too complicated to be developed and implemented in time and became the application's main bottleneck, but remained as one of several other suggestions for further work in this project.
5

Predicting Human Movement Patterns in an Office Environment

Hagnell, Fredrik January 2016 (has links)
This project is built on the idea of predicting future human movement in an area. The algorithm’s predictions are based on previous movements in the area which has to be recorded somehow. For this a device with a motion sensor was setup to monitor the movement in a hallway in an office. This data was then used to test and evaluate the prediction algorithm. To give feedback about the movement and how it is changing to the people working in the office the setup device shows sentences on a monitor which describes the movement. The project resulted in a fully working application which measures people walking by, both when and how fast, and predicts future movement. Due to time constraints of the project the device was only up and running for two weeks. This is enough time to get some understanding of how well the prediction algorithm works, but a longer experiment time would have further helped the evaluation. The results showed that the algorithm can predict most of the events during the day, but is bad at predicting sudden spikes or other unusual behavior. / Projektet är baserat på idén att förutse framtida mänsklig rörelse i ett område. För att noggrant kunna förutse framtida rörelse så behöver man kunna mäta tidigare rörelse. För detta så sattes en anordning upp med en rörelse detektor för att mäta rörelsen i en korridor i ett kontor. Data som samlades in användes sedan för att testa och utvärdera förutsägelse algoritmen. För att ge feed-back om rörelsen och hur den ändras till människorna som jobbade i kontoret så visade anordningen meningar på en skärm som beskrev rörelsen. Projektet resulterade i en fullt fungerade applikation som mäter folk som går förbi, både när och hur snabbt, och förutser framtida rörelse. På grund av tids begränsningar i projektet så var anordningen bara uppe och mätte data i två veckor. Detta är tillräckligt mycket tid för att få någon förståelse över hur bra förutsägelse algoritmen fungerar, men en längre experiment tid skulle ha hjälpt utvärderingen. Resultaten visade att algoritmen kan förutse de flesta händelserna under dagen, men är dålig på att förutse plötsliga spikar eller annat ovanligt beteende.
6

Liquid Metal - Based Inertial Sensors for Motion Monitoring and Human Machine Interfaces

Babatain, Wedyan 07 1900 (has links)
Inertial sensing technologies, including accelerometers and gyroscopes, have been invaluable in numerous fields ranging from consumer electronics to healthcare and clinical practices. Inertial measurement units, specifically accelerometers, represent the most widely used microelectromechanical systems (MEMS) devices with excellent and reliable performance. Although MEMS-based accelerometers have many attractive attributes, such as their tiny footprint, high sensitivity, high reliability, and multiple functionalities, they are limited by their complex and expensive microfabrication processes and cumbersome, fragile structures that suffer from mechanical fatigue over time. Moreover, the rigid nature of beams and spring-like structures of conventional accelerometers limit their applications for wearable devices and soft-human machine interfaces where physical compliance that is compatible with human skin is a priority. In this dissertation, the development of novel practical resistive and capacitive-type inertial sensors using liquid metal as a functional proof mass material is presented. Utilizing the unique electromechanical properties of liquid metal, the novel inertial sensor design confines a graphene-coated liquid metal droplet inside tubular and 3D architectures, enabling motion sensing in single and multiple directions. Combining the graphene-coated liquid metal droplet with printed sensing elements offers a robust fatigue-free alternative material for rigid, proof mass-based accelerometers. Resistive and capacitive sensing mechanisms were both developed, characterized, and evaluated. Emerging rapid fabrication technologies such as direct laser writing and 3D printing were mainly adopted, offering a scalable fabrication strategy independent of advanced microfabrication facilities. The developed inertial sensor was integrated with a programmable system on a chip (PSoC) to function as a stand-alone system and demonstrate its application for real-time- monitoring of human health/ physical activity and for soft human-machine interfaces. The developed inertial sensor architecture and materials in this work offer a new paradigm for manufacturing these widely used sensors that have the potential to complement the performance of their silicon-based counterparts and extend their applications.
7

Un robot volant inspiré des insectes : De la mesure du flux optique aux stratégies de guidage visuel pour un micro hélicoptère / Flying robot inspired by insects : From optic flow sensing to visually guided strategies to control a Micro Aerial Vehicle

Expert, Fabien 21 October 2013 (has links)
Dans ce travail, nous avons premièrement développé et caractérisé des capteurs de flux optique robustes aux changements de conditions lumineuses inspirés par le système visuel de la mouche et mesurant la vitesse angulaire à l'aide de l'algorithme appelé "time of travel". En particulier, nous avons comparé les performances de capteurs mesurant visuellement la vitesse angulaire en intérieur et en extérieur. Les résultats de nos capteurs bio-inspirés ont aussi été comparés avec des capteurs de souris optique. Enfin, une nouvelle implémentation de l'algorithme "time of travel" a été proposée réduisant la charge de calcul de l'unité de traitement.Dans le cadre du projet européen CurvACE (Curved Artificial Compound Eye), nous avons aussi participé au développement du premier oeil composé courbé artificiel capable de mesurer le flux optique à haute vitesse sur une large gamme de lumière ambiante. En particulier, nous avons caractérisé ce capteur et montré sa capacité à mesurer le flux optique à l'aide de plusieurs algorithmes.Finalement, nous avons aussi développé un robot aérien miniature attaché appelé BeeRotor équipé de capteurs et de stratégies de vol imitant les insectes volants et se déplaçant de manière autonome dans un tunnel contrasté. Ce robot peut expliquer comment les abeilles contrôlent leur vitesse et leur position à l'aide du flux optique, tout en démontrant que des solutions alternatives existent aux systèmes couramment utilisés en robotique. Basé seulement sur des boucles de contrôle réagissant à l'environnement, cet hélicoptère a démontré sa capacité à voler de manière autonome dans un environnement complexe et mobile. / In this thesis, we first developed and characterized optic flow sensors robust to illuminance changes inspired by the visual system of the fly and computing the angular speed thanks to the "time of travel" scheme. In particular, we have compared the performances of sensors processing the visual angular speed based on a standard retina or an aVLSI retina composed of pixels automatically adapting to the background illuminance in indoor and outdoor environments. The results of such bio-inspired sensors have also been compared with optic mouse sensors which are used nowadays on Micro Aerial Vehicles to process the optic flow but only in outdoor environments. Finally, a new implementation of the "time of travel" scheme has been proposed reducing the computational load of the processing unit.In the framework of the European project CurvACE, we also participated to the design and development of the first curved artificial compound eye including fast motion detection in a very large range of illuminations. In particular, we characterized such sensor showing its ability to extract optic flow using different algorithms.Finally, we also developed a tethered miniature aerial robot equipped with sensors and control strategies mimicking flying insects navigating in a high-roof tunnel. This robot may explain how honeybees control their speed and position thanks to optic flow, while demonstrating alternative solution to classical robotic approach relying on ground-truth and metric sensors. Based only on visuomotor control loops reacting suitably to the environment, this rotorcraft has shown its ability to fly autonomously in complex and unstationary tunnels.
8

High-response hydraulic linear drive with integrated motion sensor and digital valve control

Šimic, Marko, Herakovič, Niko January 2016 (has links)
Main purpose of the paper is to present high-response hydraulic linear drive, which is controlled with new digital piezo valve and where the new position transducer is integrated as a part of hydraulic cylinder. Hydraulic digital piezo valve with main static and dynamic characteristics as well as its functionality is presented in detail. The main static and dynamic characteristics of dygital piezo valve which influence directly on the linear drive performance are high resolution of the volume flow rate and high resposne of the valve. Beside valve characteristics the new integrated position transducer, the digital controller and control method, presented in the paper, have major impact on linear drive preformance. At the end of the paper the step response and position resolution of the hydraulic linear drive controlled with the new digital valve is compared with the results of reference hydraulic drive controlled with high response proportional valve.
9

Low-Power Biopotential Signal Acquisition System for Biomedical Applications

Tasneem, Nishat Tarannum 05 1900 (has links)
The key requirements of a reliable neural signal recording system include low power to support long-term monitoring, low noise, minimum tissue damage, and wireless transmission. The neural spikes are also detected and sorted on-chip/off-chip to implement closed-loop neuromodulation in a high channel count setup. All these features together constitute an empirical neural recording system for neuroscience research. In this prospectus, we propose to develop a neural signal acquisition system with wireless transmission and feature extraction. We start by designing a prototype entirely built with commercial-off-the-shelf components, which includes recording and wireless transmission of synthetic neural data and feature extraction. We then conduct the CMOS implementation of the low-power multi-channel neural signal recording read-out circuit, which enables the in-vivo recording with a small form factor. Another direction of this thesis is to design a self-powered motion tracking read-out circuit for wearable sensors. As the wearable industry continues to advance, the need for self-powered medical devices is growing significantly. In this line of research, we propose a self-powered motion sensor based on reverse electrowetting-on-dielectric (REWOD) with low-power integrated electronics for remotely monitoring health conditions. We design the low-power read-out circuit for a wide range of input charges, which is generated from the REWOD sensor.
10

Sårbarhetsanalys av IKEA TRÅDFRI rörelsesensor / Vulnerability analysis of IKEA TRÅDFRI motion sensor

Hyrkäs, Nathalie, Karlsson, Erik January 2021 (has links)
Arbetet utvärderar Ikea TRÅDFRI rörelsesensors kommunikationsprotokoll utifrån ett säkerhetsperspektiv. Internet of Things expanderar och i takt med utvecklingen är det viktigt att granska produkter på marknaden för att se hur säkerhet är implementerat. I rapporten utforskas flera olika sätt att utvärdera produkten för att få en god helhetsbild. Detta innefattar metoder kring hur en obehörig kan få tillgång till information genom avlyssning, ifall en obehörig skulle kunna ta över kommunikationen genom att parkoppla till en ljuskälla på ett långt avstånd samt en bedömning av sårbarhetsgrad utifrån Totalförsvarets forskningsinstituts kartläggning. Resultatet påvisar möjligheten att utnyttja enheten genom en sidokanalsattack samt hur parkoppling kan ske på ett längre avstånd än vad som enligt specifikationen ska vara möjligt. / This report evaluates the Ikea TRÅDFRI motion sensor communication protocol from a security point of view. Internet of Things is constantly expanding and with its growth it is important to examine products on the market to see how security is implemented. Different options on ways to evaluate the product is explored in the report. That includes methods of how an unauthorized person could gain access to information through eavesdropping, if they could take over the communication by pairing to a light source from a long distance, and an assessment of the degree of vulnerability by Totalförsvarets forskningsinstitut. The results show that it is possible to exploit the device through a side-channel attack and also how pairing is enabled on a longer distance than what is specified.

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