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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

RF-based location system for communicating and monitoring vehicles in a multivehicle network

Unknown Date (has links)
This document reports on a hands-on project aimed at learning and experiencing the concept of system-of-systems. The motivation behind this project is to study and implement the concept of System of Systems in the generation of a RF-based communication and control complex system. The goal of this project is to develop a multi-level integrated and complete system in which the vehicles that belong to a same network can become aware of their location, communicate with nearby vehicles (sometimes with no visible line of sight), be notified of the presence of different objects located in their immediate vicinity (obstacles, such as abundant vehicles), and generate a two dimensional representation of the vehicles’ location for a remote user. In addition, this system will be able to transmit back messages from the remote user to a specific or to all local vehicles. The end result is a demonstration of a complex, functional, and robust system built and tested for other projects to use and learn from. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015 / FAU Electronic Theses and Dissertations Collection
2

Developing and applying precision animal farming tools for poultry behavior monitoring

Li, Guoming 30 April 2021 (has links)
Appropriate measurement of broiler behaviors is critical to optimize broiler production efficiency and improve precision management strategies. However, performance of different precision tools on measuring broiler behaviors of interest remains unclear. This dissertation systematically developed and evaluated radio frequency identification (RFID) system, image processing, and deep learning for automatically detecting and analyzing broiler behaviors. Then different behaviors (i.e., feeding, drinking, stretching, restricted feeding) of broilers under representative management practices were measured using the developed precision tools. The broilers were Ross 708 in weeks 4-8. The major findings show that the RFID system achieved high performance (over 90% accuracy) for continuously tracking feeding and drinking behaviors of individual broilers, after they were customized and modified, such as tag sensitivity test, power adjustment, radio wave shielding, and assessment of interference by add-ons. The image processing algorithms combined with a machine learning model were customized and adjusted based on the experimental conditions and finally achieved 85% sensitivity, specificity, and accuracy for detecting bird number at feeder and at drinkers. After adjusting labeling method and hyperparameter tuning, the faster region-based convolutional neural network (faster R-CNN) had over 86% precision, recall, specificity, and accuracy for detecting broiler stretching behaviors. In comprehensive algorithms, the faster R-CNN showed over 92% precision, recall, and F1 score for detecting feeder, eating birds, and birds around feeder. The bird trackers had a 3.2% error rate to track individual birds around feeder. The support vector machine behavior classifier achieved over 92% performance for classifying walking birds. Image processing model was also developed to detect birds that were restricted to feeder access. Broilers had different behavior responses to different sessions of a day, bird ages, environments, diets, and allocated resources. Reducing stocking density, increasing feeder space, and applying poultry-specific light spectrum and intensity were beneficial for birds to perform behaviors, such as feeding, drinking, and stretching, while using the antibiotics-free diet reduced bird feeding time. In conclusion, the developed tools are useful tools for automated broiler behavior monitoring and the measured behavior responses provide insights into precision management of welfare-oriented broiler production.
3

Etude de qualité et de stabilité des réseaux aéronautiques embarqués HVDC / Quality and stability studies of aircraft embedded networks HVDC

Charrada, Madiha 21 February 2013 (has links)
Dans le contexte du concept de l’avion «plus électrique », l’électricité prend une part croissante dans les systèmes embarqués aéronautiques. Ainsi, de nombreuses évolutions ont eu lieu, concernant les réseaux de bord, notamment l’architecture du réseau qui est devenue de plus en plus complexe, intégrant de nombreux équipements de différentes natures ; ceci entraîne de multiples questions relatives à la qualité et la stabilité du réseau. C’est dans ce contexte que s’inscrivent ces travaux de thèse, qui aboutissent d’une part à la mise en œuvre de méthodes d’analyse de la stabilité et de la qualité du réseau aéronautique embarqué et d’autre part à l’analyse de couplage entre plusieurs équipements connectés sur un seul réseau. Les études menées au cours de ces travaux reposent sur l’utilisation des expressions analytiques représentant le comportement fréquentiel de réseaux continus. Une méthode de calcul basée sur les lois de la physique a été développée et validée par des approches de simulation et d’expérimentation. Par ailleurs, en absence d’un modèle analytique, nous choisissons de déterminer l'expression littérale du modèle équivalent du réseau à partir de l'identification des données issues de l’approche expérimentale en se basant sur des algorithmes d'optimisation. Ces modèles analytiques sont associés aux critères mathématiques de stabilité (Routh-Hurwitz, MiddleBrook), et aux contraintes de qualité imposées par les standards aéronautiques, dans le but de dimensionner les éléments de filtrage à placer entre le réseau et l’équipement. Le calcul des composants assurant le filtrage repose sur la recherche d’une solution optimale : nous introduisons les algorithmes d’optimisation utilisés en première étape, et nous proposons par la suite une formulation de la procédure de calcul des paramètres du filtre pour une meilleure illustration des résultats intéressants pour un concepteur de réseau. Enfin, nous clôturons ce travail par une analyse des couplages entre plusieurs équipements connectés sur un réseau continu et nous concluons par une approche expérimentale afin d’appuyer les résultats théoriques. / In the concept of the "more electric" aircraft, power takes an increasing proportion in aeronautic embedded systems. So many changes have occurred on board networks, including the network architecture that has become more and more complex, integrating many different types of equipment that causes quality and stability issues on the network. In this context that this thesis is inscribed, firstly it leads to the implementation of methods for stability and quality analyzing of the embedded network and secondly to coupling analysis of several devices connected to a single network. Studies conducted in this work are based on analytical expressions representing the frequency behavior of networks. A compute based on fundamental physical laws has been developed and validated by simulation and experimental approaches. Moreover, in the absence of an analytical model, we choose to determine the literal expression of the equivalent model of the network by identifying data, come from the experimental approach, using optimization algorithms. These analytical models are associated with mathematical criteria: Routh-Hurwitz, Middlebrook, and quality constraints imposed by aeronautic standards, in order to size the elements of the filter cell placed between the voltage source and the equipment to ensure the stability and quality of the entire system. The sizing of cell parameters based on optimal search by means of optimization algorithms in the first step, and then we propose a formulation of the calculation procedure of the filter parameters to illustrate some interesting results for designer’s network. Finally, we close this work with a coupling analysis of several devices connected to a single DC bus and we conclude by an experimental approach to support the theoretical results.

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