102 research outputs found

    Remote control and monitoring of a hybrid power system

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    Includes abstract.Includes bibliographical references (leaves 90-92).Increasingly, South Africa is developing a need for grid-independent power systems. Many options exist already in the form of diesel generators, solar panels and wind generators. This project is to do with marrying the various sources of power with efficient and intelligent control. Specifically, the terms of reference describe an existing solution that has been developed. The focus of this thesis is to design a replacement system for the existing system which incorporates many communication technologies and additional features. The design centres on a central digital signal processor board. The redesign of this hardware and software will form the bulk of the content of this document. The scope of the design encompasses all the communications and new features including remote programming, control and monitoring software and robustness. The new system is to form the infrastructure or base hardware and software for many different power-related applications. A specific example of such an application, the hybrid power system, is discussed in detail to demonstrate the success of the design

    DESIGN MODULAR COMMAND AND DATA HANDLING SUBSYSTEM HARDWARE ARCHITECTURES

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    Over the past few years, On-Board Computing Systems for satellites have been facing a limited level of modularity. Modularity is the ability to reuse and reconstruct the system from a set of predesigned units, with minimal additional engineering effort. CDHS hardware systems currently available have a limited ability to scale with mission needs. This thesis addresses the integration of smaller form factor CDHS modules used for nanosatellites with the larger counterparts that are used for larger missions. In particular, the thesis discusses the interfacing between Modular Computer Systems based on Open Standard commonly used in large spacecrafts and PC/104 used for nanosatellites. It also aims to create a set of layers that would represent a hardware library of COTS-like modules. At the beginning, a review of related and previous work has been done to identify the gaps in previous studies and understand more about Modular Computer Systems based on Open Standard commonly used in large spacecrafts, such as cPCI Serial Space and SpaceVPX. Next, the design requirements have been set to achieve this thesis objectives, which included conducting a prestudy of system alternatives before creating a modular CDHS hardware architecture which was later tested. After, the hardware suitable for this architecture based on the specified requirements was chosen and the PCB was designed based on global standards. Later, several functional tests and communication tests were conducted to assess the practicality of the proposed architecture. Finally, thermal vacuum testing was done on one of the architecture’s layers to test its ability to withstand the space environment, with the aim to perform the vibration testing of the full modular architecture in the future. The aim of this thesis has been achieved after going through several tests, comparing between interfaces, and understanding the process of interfacing between different levels of the CDHS. The findings of this study pave the way for future research in the field and offer valuable insights that could contribute to the development of modular architectures for other satellite subsystems

    Reducing User Perceived Latency in Smart Phones Exploiting IP Network Diversity

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    The Fifth Generation (5G) wireless networks set its standard to provide very high data rates, Ultra-Reliable Low Latency Communications (URLLC), and significantly improved Quality of Service (QoS). 5G networks and beyond will power up billions of connected devices as it expands wireless services to edge computing and the Internet of Things (IoT). The Internet protocol suite continues its evolution from IPv4 addresses to IPv6 addresses by increasing the adoption rate and prioritizing IPv6. Hence, Internet Service Providers (ISP's) are using the address transition method called dual-stack to prioritize the IPv6 while supporting the existing IPv4. But this causes more connectivity overhead in dual-stack as compared to the single-stack network due to its preference schema towards the IPv6. The dual-stack network increases the Domain Name System (DNS) resolution and Transmission Control Protocol (TCP) connection time that results in higher page loading time, thereby significantly impacting the user experience. Hence, we propose a novel connectivity mechanism, called NexGen Connectivity Optimizer (NexGenCO), which redesigns the DNS resolution and TCP connection phases to reduce the user-perceived latency in the dual-stack network for mobile devices. Our solution utilizes the IP network diversity to improve connectivity through concurrency and intelligent caching. NexGenCO is successfully implemented in Samsung flagship devices with Android Pie and further evaluated using both simulated and live-air networks. It significantly reduces connectivity overhead and improves page loading time up to 18%

    IoT on Shared Vehicles

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    Nowadays the need of people to have the power to control everything is increasing. Due to the technological evolution together with the Internet of things, this is already possible. In this context, the shared vehicles are a good example. With just one click people can use a vehicle from a vehicle sharing eet anywhere, anytime. During the realization of this project the uMDC was developed. It is a small device capable of managing and controlling di erent types of vehicles, with the main focus being the electric bicycles. As a nal conclusion of the project, the results obtained with the uMDC have proved very attractive. During its integration in the electric bicycles, the system was capable of controlling the bicycle's di erent components, as required for the rst prototype.Hoje em dia, a necessidade das pessoas terem controlo sobre tudo está a aumentar. Devido á evolução tecnológica juntamente com a Internet das coisas, isso já é possível. Neste contexto, os veículos partilhados são um bom exemplo disso. Com um simples clique, as pessoas podem usufruir e uma viatura de uma frota de veículos partilhados em qualquer lugar, a qualquer hora. Durante a realização deste projeto, foi desenvolvido o uMDC. Um pequeno ispositivo capaz de gerir e controlar diferentes tipos de veículos, sendo o foco principal as bicicletas elétricas. No nal deste projeto, os resultados obtidos com o uMDC foram bastante satisfatórios. Durante a sua integração nas bicicletas elétricas, o sistema foi capaz de controlar diferentes componentes das mesmas, como requerido para primeiro protótipo

    Design of a remote monitoring and diagnostics platform for air conditioning installations

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    Includes abstract.Includes bibliographical references (p. 127-129).Faults and inefficiencies in air conditioning installations account for between 2% and 11% of allenergy consumed by commercial buildings in the United States each year. Diagnostics systems havebeen proven to improve the performance of air conditioning plants but the high costs of purchasing,retrofitting and maintaining such a system results in limited market adoption of such systems.This thesis discusses the design, implementation and results of low-cost remote monitoring anddiagnostic platform for use in air conditioning installations. The design of the various hardwarecomponents is presented along with the structure of the framework developed for each device. The thesis also contains information regarding the selection, integration and installation of the various types of sensors required on the various installations. A specially-designed protocol was also developed to handle communication between the hardware devices. Both the physical configuration and details of the protocol structure are presented in detail in this thesis. The mechanism through which the device uploads data to a server is also described in this thesis and includes details on both the hardware and the server technologies used in the upload process. The system has been installed on two different sites in Cape Town, South Africa and has produced meaningful diagnostic information since November 2007

    PROPOSED MIDDLEWARE SOLUTION FOR RESOURCE-CONSTRAINED DISTRIBUTED EMBEDDED NETWORKS

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    The explosion in processing power of embedded systems has enabled distributed embedded networks to perform more complicated tasks. Middleware are sets of encapsulations of common and network/operating system-specific functionality into generic, reusable frameworks to manage such distributed networks. This thesis will survey and categorize popular middleware implementations into three adapted layers: host-infrastructure, distribution, and common services. This thesis will then apply a quantitative approach to grading and proposing a single middleware solution from all layers for two target platforms: CubeSats and autonomous unmanned aerial vehicles (UAVs). CubeSats are 10x10x10cm nanosatellites that are popular university-level space missions, and impose power and volume constraints. Autonomous UAVs are similarly-popular hobbyist-level vehicles that exhibit similar power and volume constraints. The MAVLink middleware from the host-infrastructure layer is proposed as the middleware to manage the distributed embedded networks powering these platforms in future projects. Finally, this thesis presents a performance analysis on MAVLink managing the ARM Cortex-M 32-bit processors that power the target platforms

    Flexi-WVSNP-DASH: A Wireless Video Sensor Network Platform for the Internet of Things

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    abstract: Video capture, storage, and distribution in wireless video sensor networks (WVSNs) critically depends on the resources of the nodes forming the sensor networks. In the era of big data, Internet of Things (IoT), and distributed demand and solutions, there is a need for multi-dimensional data to be part of the Sensor Network data that is easily accessible and consumable by humanity as well as machinery. Images and video are expected to become as ubiquitous as is the scalar data in traditional sensor networks. The inception of video-streaming over the Internet, heralded a relentless research for effective ways of distributing video in a scalable and cost effective way. There has been novel implementation attempts across several network layers. Due to the inherent complications of backward compatibility and need for standardization across network layers, there has been a refocused attention to address most of the video distribution over the application layer. As a result, a few video streaming solutions over the Hypertext Transfer Protocol (HTTP) have been proposed. Most notable are Apple’s HTTP Live Streaming (HLS) and the Motion Picture Experts Groups Dynamic Adaptive Streaming over HTTP (MPEG-DASH). These frameworks, do not address the typical and future WVSN use cases. A highly flexible Wireless Video Sensor Network Platform and compatible DASH (WVSNP-DASH) are introduced. The platform's goal is to usher video as a data element that can be integrated into traditional and non-Internet networks. A low cost, scalable node is built from the ground up to be fully compatible with the Internet of Things Machine to Machine (M2M) concept, as well as the ability to be easily re-targeted to new applications in a short time. Flexi-WVSNP design includes a multi-radio node, a middle-ware for sensor operation and communication, a cross platform client facing data retriever/player framework, scalable security as well as a cohesive but decoupled hardware and software design.Dissertation/ThesisDoctoral Dissertation Electrical Engineering 201

    Portable Computer Technology (PCT) Research and Development Program Phase 2

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    The subject of this project report, focused on: (1) Design and development of two Advanced Portable Workstation 2 (APW 2) units. These units incorporate advanced technology features such as a low power Pentium processor, a high resolution color display, National Television Standards Committee (NTSC) video handling capabilities, a Personal Computer Memory Card International Association (PCMCIA) interface, and Small Computer System Interface (SCSI) and ethernet interfaces. (2) Use these units to integrate and demonstrate advanced wireless network and portable video capabilities. (3) Qualification of the APW 2 systems for use in specific experiments aboard the Mir Space Station. A major objective of the PCT Phase 2 program was to help guide future choices in computing platforms and techniques for meeting National Aeronautics and Space Administration (NASA) mission objectives. The focus being on the development of optimal configurations of computing hardware, software applications, and network technologies for use on NASA missions

    The use of Sensor Networks to create smart environments

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    Internet of Things is taking the world in order to be the next big thing since the Internet, with almost every object being connected to gather data and allow control through mobile and web devices. But this revolution has some barriers with the lack of standardization in communications or sensors. In this dissertation we present a proposal of a system dedicated to creating smart environments using sensor networks, with a practical application developed to achieve automation, efficiency and versatility, allowing real-time monitoring and remote control of any object or environment improving user experience, tasks efficiency and leading to costs reduction. The developed system, that includes software and hardware, is based on adaptive and Artificial Intelligence algorithms and low cost IoT devices, taking advantage of the best communication protocols, allowing the developed system to be suited and easily adapted to any specification by any person. We evaluate the best communication and devices for the desired implementa tion and demonstrate how to create all the network nodes, including the build of a custom IoT Gateway and Sensor Node. We also demonstrate the efficiency of the developed system in real case scenarios. The main contributions of our study are the design and implementation of a novel architecture for adaptive IoT projects focus on environment efficiency, with practical demonstration, as well as comparison study for the best suited communication protocols for low cost IoT devices.A Internet of Things está a atingir o mundo de modo a tornar-se a próxima grande revolução depois da Internet, com quase todos os objectos a estarem ligados para recolher dados e permitir o controlo através de dispositivos móveis. Mas esta revolução depara-se com vários desafios devido à falta de standards no que toca a comunicações ou sensores. Nesta dissertação apresentamos uma proposta para um sistema dedicado a criar ambientes inteligentes usando redes de sensores, com uma aplicação prática desenvolvida para oferecer automação, eficiência e versatilidade, permitindo uma monitorização e controlo remoto seguro em tempo real de qualquer objecto ou ambiente, melhorando assim a experiência do utilizador e a eficiência das tarefas evando a redução de custos. O sistema desenvolvido, que inclui software e hard ware, usa algoritmos adaptáveis com Inteligência Artificial e dispositivos IoT de baixo custo, utilizando os melhores protocolos de comunicação, permitindo que o mesmo seja apropriado e facilmente adaptado para qualquer especificação por qualquer pessoa. Avaliamos os melhores métodos de comunicação e dispositivos necessários para a implementação e demonstramos como criar todos os nós da rede, incluindo a construção de IoT Gateway e Sensor Node personalizados. Demonstramos também a eficácia do sistema desenvolvido através da aplicação do mesmo em casos reais. As principais contribuições do nosso estudo passam pelo desenho e implemen tação de uma nova arquitectura para projectos adaptáveis de IoT com foco na eficiência do objecto, incluindo a demonstração pratica, tal como um estudo com parativo sobre os melhores protocolos de comunicação para dispositivos IoT de baixo custo
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