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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.
181

Sistema Telemétrico para Monitoramento de Trens Através de Redes de Sensores sem Fio e Processamento em Sistema Embarcado

Santos, Jerry Lee Alves dos 05 March 2010 (has links)
Made available in DSpace on 2015-05-14T12:36:55Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2425731 bytes, checksum: 3f05e964526e281aa2761b2a01cac8f6 (MD5) Previous issue date: 2010-03-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present study portrays the development of a telemetric system integrating wireless sensor networks and data processing into an embedded system for monitoring vehicles in metropolitan railway networks, enabling real-time monitoring of train movements. The main objective of this system is to allow constant evaluation of numerous factors which can influence train performance, such as speed and pressure in air bags. By so doing, it may become possible to generate information so as to facilitate intervention strategies, thereby preventing the partial or total degradation of the transport services provided to the population. In order to perform real-time telemetry, wireless sensor networks with ZigBee technology will be mounted alongside the entire route of the train traffic. These networks capture and transmit data collected in each train until they reach base stations where a processing embedded system in an FPGA is responsible for receiving the data, performing the necessary calculations and sending the obtained information to a central monitoring system through an Ethernet network. The embedded system functions as a data server providing information to a monitoring system installed in the Operational Control Center (OCC) and in other sectors requiring this information. The use of a dedicated processing device such as an FPGA gives the system far greater efficiency than that typically found in general purpose processors. Furthermore, it allows the customization of the hardware, thus reducing the final cost of the system. The monitoring system installed in the OCC is responsible for managing the storage and display of the data received. It will display the data in tables and graphs in real time, enabling the traffic controllers to analyze the operation of each train and also to detect possible problems. The system also stores the data in a database for further study. Keywords: Telemetry, Wireless Sensor Networks, ZigBee Protocol, Embedded Systems, Nios II processor, FPGA. / Este trabalho apresenta o desenvolvimento de um sistema telemétrico que integra redes de sensores sem fio e processamento de dados em sistema embarcado para monitoramento de veículos em redes de transportes metroferroviários, possibilitando um acompanhamento em tempo real do movimento dos trens. Este sistema tem como principal objetivo permitir uma constante avaliação de vários fatores que influenciam o desempenho dos trens, como velocidade e pressão nas bolsas de ar, de forma a gerar informações que possibilitem estratégias de operação e manutenção, evitando assim uma degradação parcial ou total dos serviços de transporte prestados à população. Para realizar a telemetria em tempo real, redes de sensores sem fio com tecnologia ZigBee são montadas em toda a via de tráfego. Estas redes realizam a captação e envio dos dados coletados em cada trem até estações base onde um sistema de tratamento embarcado em um FPGA fica encarregado de receber os dados, realizar os cálculos necessários e enviar as informações obtidas, através de uma rede ethernet, a um sistema central de supervisão. O sistema embarcado atua como um servidor de dados disponibilizando informações para um sistema de supervisão instalado no Centro de Controle de Operações (CCO) e em outros setores que necessitem destas informações. A utilização de um dispositivo de processamento dedicado, como uma FPGA, proporciona ao sistema uma eficiência muito maior do que normalmente é encontrada em processadores de uso geral, além de permitir a customização do hardware, reduzindo o custo final do sistema. O sistema de supervisão instalado no CCO é responsável por gerenciar o armazenamento e a visualização dos dados recebidos. Ele exibe os dados em tabelas e gráficos em tempo real permitindo aos controladores de tráfego analisar o funcionamento de cada trem e detectar possíveis problemas. O sistema também armazena os dados em um banco de dados para realização de estudos posteriores.
182

An?lise de desempenho de rede de comunica??o para um sistema multi VANT aplicado ? varredura de ?rea de impacto de foguetes / Communication network performance analysis for a multi-UAV system applied to rocket impact area scanning

Silva, Maur?cio Rabello 01 December 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-12T13:20:58Z No. of bitstreams: 1 MauricioRabelloSilva_DISSERT.pdf: 3313926 bytes, checksum: d44b18b0d82c7e9f5b8b79b80f69458e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-14T14:47:18Z (GMT) No. of bitstreams: 1 MauricioRabelloSilva_DISSERT.pdf: 3313926 bytes, checksum: d44b18b0d82c7e9f5b8b79b80f69458e (MD5) / Made available in DSpace on 2018-03-14T14:47:19Z (GMT). No. of bitstreams: 1 MauricioRabelloSilva_DISSERT.pdf: 3313926 bytes, checksum: d44b18b0d82c7e9f5b8b79b80f69458e (MD5) Previous issue date: 2017-12-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Pesquisas relacionadas com sistemas utilizando diversos ve?culos a?reos n?o tripulados (multi VANTs) v?m crescendo nos ?ltimos anos. Entre os desafios enfrentados, uma rede de comunica??o de dados robusta ? crucial para coopera??o e colabora??o entre VANTs. No projeto da rede devem ser levados em conta fatores como o prop?sito da miss?o da esquadrilha, planejamento de caminho e trajet?ria, coleta de dados dos sensores e suprimento energ?tico. Dessa forma, o presente trabalho apresenta a especifica??o de uma arquitetura de rede de comunica??o de dados para uma esquadrilha de Ve?culos A?reos N?o Tripulados a serem utilizados na varredura da ?rea de impacto de foguetes lan?ados a partir do Centro de Lan?amento da Barreira do Inferno (CLBI ? Rio Grande do Norte). Assim, realiza-se um estudo sobre as principais caracter?sticas das redes de comunica??o para sistemas multi VANT e as especificidades da aplica??o abordada nesse projeto. S?o propostas duas estrat?gias diferentes para a varredura da ?rea de impacto de foguetes. S?o analisadas as caracter?sticas das redes para sistemas multi VANTs mais adequadas a essas estrat?gias, de forma a fazer uma an?lise comparativa entre as mesmas e definir uma arquitetura apropriada para a aplica??o. Dentro desse contexto, ? proposta uma arquitetura de rede, com base em m?dulos XBee Pro 900HP, integrados em uma plataforma de hardware controlada por computador embarcado, equipado com GPS e placa controladora de piloto autom?tico. ? idealizado e implementado um plano de testes com os dispositivos XBee para avaliar o desempenho destes na arquitetura de rede proposta em termos de robustez, confiabilidade e economia de energia. Para aferi??o do desempenho nos poss?veis cen?rios de forma??o da esquadrilha de VANTs s?o utilizados softwares de ger?ncia de rede, visando medir a largura de banda (throughput), perda de pacotes e outros indicadores de desempenho nos links de comunica??o entre os diferentes n?s da rede. / Research on Multi Unmanned Aerial Vehicle Systems (Multi-UAV) is growing in recent years. Among several scientific and technical challenges, a robust data communication network is crucial for the cooperation and collaboration between the UAVs. The network design must take into account factors such as the purpose of the mission, trajectory and path planning, sensor data collection and energy supply. In this way, the present work presents the specification of a data communication network architecture for a squadron of Unmanned Aerial Vehicles to be used in the scanning of the rocket impact area for CLBI rocket launch center (Rio grande do Norte, Brazil). Thus, a study on the main characteristics of communication networks for multi-UAV systems and the specificities of the application addressed in this project is done. Two different strategies for the scanning of the rocket impact area are proposed. In order to do a comparative analysis between these strategies and to define an appropriate architecture for the application, the characteristics of the networks for multi-UAV systems that are more appropriate to them are analyzed. In this context, a network architecture based on Xbee Pro 900HP S3B modules, integrated in an embedded computer hardware platform, equipped with GPS and autopilot controller board is proposed. A test plan with Xbee devices is conceived and implemented in order to evaluate their performance in the proposed network architecture in terms of robustness, reliability and energy consumption. In order to measure performance in the possible UAV squad formation scenarios, a network management software is used to measure throughput, packet loss and other performance indicators in the communication links between the different nodes of the network.
183

Cattle monitoring and theft prevention system using ZigBee and WiFi

Nkwari, Patrick Kibambe Mashoko 16 September 2015 (has links)
M.Ing. / Please refer to full text to view abstract
184

Univerzální domácí brána pro IoT zařízení / Universal Home Gateway for IoT Devices

Šelinga, Martin January 2018 (has links)
This diploma thesis consists of theoretical description of M2M communication and main differences comparing with H2H communication. There is also a description of protocols used in Internet of Things and description of practical implementation of protocols WM-BUS and Z-Wave in Python programming language with usage of Django framework.
185

Nástroj pro testování komunikace vloženého zařízení pomocí AT příkazů / Software tester of embedded module communication based on AT commands

Kondr, Aleš January 2008 (has links)
The graduation thesis deals with AT commands and the implementation of these in modules of wireless communication. These commands are mainly used for the obtaining and setting of different parameters of such modules. A form of the AT commands and a manner in which these are sent to modules are described. For selected wireless modules, there is a set of AT commands determined together with a brief description of the functions of these. A manner of creation of macroblocks for the TeraTerm program is also mentioned; macroblocks are able to establish communication with the module connected and allow for measurement and testing of communication appliances. This is suitable especially for the automation of such a process. As such a system (program) is not widely known, a thorough description of this system is given together with a description of measuring and testing macroblocks. The last part of the thesis deals with the creation of an application enabling the user to control quickly and easily an inserted appliance. A very detailed description of this application is given. Due to an absence of an advanced graphic interface, such an application has not been created by means of a system of macroblocks for the TeraTerm program, but it has been created in the JAVA programming language.
186

Monitor bezdrátové sítě / Wirelles netowrok monitor

Slováček, Miroslav January 2009 (has links)
This master´s thesis deal with designing of the system for ZigBee wireless network monitoring. In the first, treoretical part, is reader introduced to this wireless standard. Acquired informations are possible to compare with the simillar wireless standards. Next part of this document describes procedure of designing harward part of modular system - motherboard and scanning module. In this place is so discussion about component parameters, which are very needed to keep. One part of this discussion is about the problems with wrong component parameters. The last part of this master´s thesis is about software part of this project and so shows designed system in work.
187

Realizace bezdrátové senzorové sítě s mikrokontroléry Atmel AVR / Wireless Sensor Network with Atmel AVR Microcontrollers.

Mráz, Ľubomír January 2010 (has links)
This diploma thesis describes the standard IEEE802.15.4 and Zigbee for wireless sensor networks. These norms are described in detail in the first two chapters. The main priority of the wireless sensor networks is to minimize the power of the devices and the price while maximizing the reliability of the data transfer. Minimum consumption is provided by the significantly lowered complexity in comparison to the standard wireless networks. Further, the design of the concept of the complex and universal hardware platform focused on intelligent building is described. Software implementation of those norms is described in the chapters five and six. Finally, comparison of the designed hardware platform and the other commercial platforms is described in the last chapter.
188

Návrh, realizace a simulace síťových protokolů v NS2 / Design, realization and simulation of network protocols in NS2

Zvolenský, Daniel January 2010 (has links)
The aim of this work is to become familiar with simulation environment Network Simulator 2, study the problems of sensor networks and their support in the simulator and implement the selected protocol and verify its funcitonality in a practical simulation.
189

Zpracování signálů v systému ZigBee / Signal processing in ZigBee system

Miloš, Jiří January 2010 (has links)
Master's thesis The Signal Processing in ZigBee System is focused on properties of Physical Layer of ZigBee (standard IEEE 802.15.4 - 2003). The work consists of three parts. The first part contains common view on using and properties of ZigBee. The next part focuses on the Medium Access Control Layer and in detail on the Physical Layer. There described signal processing in the Physical Layer in individual radio bands. The last part of the project contains the process of modeling in the MATLAB for both models of system ZigBee (bands 868/915 MHz and 2450 MHz). The last part of thesis deals with the simulations of BER depending on Carrier-to-Noise Ratio. Also examined the coexistence of systems operating in the same or a nearby frequency band. Based on the results of simulations there are given recommendations for the use of the ZigBee system in minimizing BER.
190

Monitorování parametrů prostředí v budovách / Monitoring of environmental parameters in buldings

Slovák, Martin January 2010 (has links)
Aim of work is project system for monitoring environmental parameters in buildings. Theoretical part of work deals with parameters, which will be monitoring, why we measure those parameters in buildings. And what devices can we choose to do it. Measurement channel describes from change of physical value to electric value, after that there is a correction to processing by microcontroller. And those values are sending by microcontroller to other processing. The best solution to distant transmission is probably ZigBee technology. Practice part of work is in keeping with theoretical part. There are some practical sensor connections, where is difference in output of sensor. It’s necessary to project connections of sensor and do their software services. There is a simple tool to programming microcontrollers, which is called CodeWarrior. In last part is solution of algorithm, which make net by ZigBee technology.

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