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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.
221

Geração automática de código para redes de sensores sem fio usando Communicating X-machine

Braga, Marcus de Lima 05 January 2012 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-02-18T18:24:40Z No. of bitstreams: 1 Dissertação - Marcus de Lima Braga.pdf: 6450946 bytes, checksum: 146975a14889793868be80d04a6c46c5 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-02-18T19:37:05Z (GMT) No. of bitstreams: 1 Dissertação - Marcus de Lima Braga.pdf: 6450946 bytes, checksum: 146975a14889793868be80d04a6c46c5 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-02-18T19:39:18Z (GMT) No. of bitstreams: 1 Dissertação - Marcus de Lima Braga.pdf: 6450946 bytes, checksum: 146975a14889793868be80d04a6c46c5 (MD5) / Made available in DSpace on 2016-02-18T19:39:18Z (GMT). No. of bitstreams: 1 Dissertação - Marcus de Lima Braga.pdf: 6450946 bytes, checksum: 146975a14889793868be80d04a6c46c5 (MD5) Previous issue date: 2012-01-05 / Não informada / Wireless Sensor Network (WSN) has attracted the interest of researchers in applications development that operate on monitoring and control of physical phenomena, relying on its autonomy and exibility, and on its distributed nature and pervasive. If for one hand, this interest provides the development of new applications, on the other it increases its complexity and therefore costs. This is easily understood due their restrictive features, which make the crucial stages of software development (modeling, veri cation and testing) become a non-trivial task. The programming is carried out very close to the operating system (low level), favoring the distraction in the application of logic and thus requiring more concentration of the developer, as well as technical training, rare among experts. This scenario enables the creation of methodologies and tools that support development on this platform. This study aims to use the formal method called Communicating X-Machine in the construction of WSN applications, o ering an intuitive approach and a modular development, providing to the programmer a higher level of abstraction, making it easier to build applications until the code generation in nesC language programming (TinyOS platform). So, this paper aims to facilitate the development of applications, from their modeling until the code generation, providing to the developer an increase in the level of abstraction, a better understanding of the problem through its partitioning and ease of building WSN applications. / Rede de Sensores Sem Fio (RSSF) tem despertado o interesse de pesquisadores no desenvolvimento de aplicações que atuem no monitoramento e controle de fenômenos físicos, apoiando-se em sua autonomia e exibilidade, e em sua natureza distribuída e pervasiva. Se por um lado, esse interesse proporciona o desenvolvimento de novas aplica- ções, por outro, eleva sua complexidade e consequentemente seus custos. Isto é facilmente entendido devido suas características restritivas, que fazem com que os estágios cruciais do desenvolvimento de software (modelagem, veri cação e testes) se tornem tarefas não triviais. A programação é realizada muito próxima ao sistema operacional (baixo nível), favorecendo a distração na aplicação da lógica e exigindo, portanto, ao desenvolvedor maior concentração, além de formação técnica rara entre os especialistas. Este cenário propicia a criação de metodologias e ferramentas que deem suporte ao desenvolvimento nesta plataforma. Este trabalho tem por objetivo utilizar o método formal Communicating X-Machine na construção de aplicações RSSF, oferecendo uma abordagem intuitiva e um desenvolvimento modular, provendo ao programador elevação no nível de abstração, facilitando a construção de aplicações até a geração de código na linguagem de programa- ção nesC (plataforma TinyOS). Portanto, o presente trabalho pretende facilitar o desenvolvimento de aplicações, desde sua modelagem até a geração de código, proporcionando ao desenvolvedor o aumento no nível de abstração, melhor entendimento do problema através de seu particionamento e facilidade na construção de aplicações em RSSF.
222

Um sistema de alerta para o monitoramento remoto do consumo de energia usando redes de sensores sem fio / An alert for remote monitoring of energy consumption using wireless sensor networks

Geraldo Pereira Rocha Filho 06 June 2014 (has links)
Determinar quais são os aparelhos eletrônicos de uma residência que possuem maior influência na conta de luz não é tarefa trivial. As Redes de Sensores Sem Fios (RSSF) auxiliam os usuários nessa tarefa, permitindo descobrir se há algum tipo de desperdício no ambiente monitorado e assim, auxiliá-los a fazer as devidas correções. Por isso, é fundamental usar nas smart grids métodos que detectam novidades, também conhecido como anomalias , de forma individual e autônoma, para os usuários quando algo anômalo surge no consumo de energia dos equipamentos eletrônicos. Tais anomalias podem surgir, por exemplo, quando um equipamento consome energia acima do esperado, o que pode indicar um defeito. Nesse contexto, este trabalho propõe um método inteligente, nomeado como Novelty Detection Power Meter (NodePM), para detectar as novidades no consumo de energia dos equipamentos eletrônicos monitorados por uma smart grid. O NodePM detecta as novidades considerando a entropia de cada equipamento monitorado, a qual é calculada com base em um modelo de cadeia de markov que é gerado através de um algoritmo de aprendizado de máquina. Para tanto, o NodePM é integrado a uma plataforma de monitoramento remoto de consumo de energia, que consiste de uma RSSF associada a uma aplicação em nuvem. Para validar o desempenho do NodePM foram feitos experimentos utilizando a análise de variância e testes paramétricos e não-paramétricos. Os resultados de tais experimentos, obtidos mediante a análise estatística, evidenciou a viabilidade do NodePM na plataforma desenvolvida / It is not a simple task to determine which pieces of elevtronic equipment have the greatest influence on the electricity bill. The Wireless Sensor Networks (WSN) assist users in this task, allowing to discover if there is any type of a waste in a monitored environment and thus, help them to take proper actions. Hence, it is of crucial importance to use intelligent methods in the smart grids for a novelty detection and to inform the users in an individual and autonomous way when some anomaly has occurred in the energy consumption of electronic equipment. These anomalies can arise, for instance, when a piece of equipment consumes more energy than expected. In this context, we propose an intelligent method, named the Novelty Detection Power Meter (NodePM), to detect the novelties in the energy consumption of electonic equipment monitored by a smart grid. The NodePM detects the novelties considering the entropy of each device monitored, which is calculed based on a Markov chain model that is generated through a machine learning algorithm. For this end, the NodePM is integrated into a platform for the remote monitoring of energy consumption, which consists of a WSN associated with a cloud application. To validate the performance of the NodePM, experiments were done using analysis of variance and parametric and non-parametric tests. The result of these tests, which were obtained from a statistical analysis, provided evidence of the feasibility of the NodePM in the platform that was developed
223

Redes de sensores sem fio na coleta de dados fisiológicos de bovinos para aplicações na zootecnia de precisão / Wireless sensor networks technology applied to bovine physiological data acquisition for precision animal production

Aldo Ivan Céspedes Arce 22 February 2008 (has links)
Este trabalho mostra a aplicação das redes de sensores sem fio na monitoração de variáveis fisiológicas de bovinos. A necessidade de experimentar técnicas de coleta de dados, que causem menos perturbações no comportamento natural dos animais de interesse da zootecnia de precisão, foi a principal motivação deste trabalho. Para testar a aplicabilidade da tecnologia das redes de sensores sem fio neste campo, foi desenvolvida uma infra-estrutura, utilizando técnicas de instrumentação eletrônica e comunicação sem fio via rádio-freqüência. A rede foi projetada com o protocolo floating base sensor network (FBSN) que implementa uma topologia adhoc com escolha aleatória dos nós. Os protótipos desenvolvidos foram utilizados para efetuar coletas de sinais cerebrais e temperaturas corporais de bovinos adultos. Foram desenvolvidos também os softwares embarcados e de supervisão e um simulador de deslocamento bovino, que foi utilizado como ferramenta de auxílio no projeto da infra-estrutura de monitoramento implementada. O consumo das fontes de energia e a relação custo-beneficio do sistema foram os principais itens avaliados. Os resultados obtidos mostraram que é possível utilizar redes de sensores sem fio como técnicas eficientes para coleta de dados fisiológicos de bovinos. / This work presents an application of wireless sensor networks technology used for bovine physiological variables monitoring. The main stimulus of this work was the precision animal production researcher\'s interest in developing and testing new techniques that could allow data acquisition with less interference in animal behavior. In order to test the feasibility of the wireless sensor network technology in this area, an infrastructure was developed using electronic instrumentation and radio frequency wireless communication techniques. The network was projected to support the floating base sensor network protocol that is a special kind of adhoc topology with randomic selection of path nodes. The developed prototypes were used to acquire brain electrical activity and body temperature from bovines. The development of supervisor and embedded software and a bovine\'s displacement simulator tool was also described here. The energy consumption and the cost-benefit relationship of the network nodes were the main evaluated features. The results obtained prove that the wireless sensor networks can be considered as an efficient technique to be used to acquire bovine\'s physiological data.
224

Infraestrutura de rede de sensores sem fio para ambientes assistivos / Wireless sensor network infrastructure for assistive environments

Teixeira, Fábio Vieira, 1987- 24 August 2018 (has links)
Orientador: Eleri Cardozo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-24T14:20:11Z (GMT). No. of bitstreams: 1 Teixeira_FabioVieira_M.pdf: 4888310 bytes, checksum: 3976274cd7d3de15a58a9eec18e4aab5 (MD5) Previous issue date: 2013 / Resumo: Na última década, as redes de sensores sem fio foram alvo de várias pesquisa em diversas áreas, entre elas a Robótica Móvel e Ambientes Inteligentes. Com o uso dessa tecnologia é possível estender as capacidades de sensoriamento de robôs móveis para o ambiente em que se encontram, além de aumentar a abrangência da conectividade sem fio. Devido à grande exploração da área e o grande avanço das tecnologias CMOS, novos módulos de sensoriamento, como câmeras, puderam ser desenvolvidos e embarcados em transceptores de baixo custo. A interconexão dessas fontes compostas de múltiplas mídias deu origem a uma nova tecnologia, as Redes de Sensores Multimídia Sem Fio. Essas redes possibilitam o desenvolvimento de uma grande quantidade de aplicações que antes não eram possíveis apenas com o uso de sensores escalares, por exemplo, em áreas relacionadas ao controle de tráfego, vigilância, automação residencial e cuidados com a saúde. Esta dissertação explora o uso desta nova tecnologia para o desenvolvimento de uma infraestrutura capaz de prover serviços a robôs móveis semi-autônomos em ambientes instrumentados para acessibilidade, a fim de auxiliá-los no cumprimento de seus objetivos / Abstract: In the last decade, Wireless Sensor Networks have been the subject of research in many areas, including Mobile Robotics and Smart Environments. Such technology enables the extension of the mobile robots' sensing capabilities towards the environment where they are operating, as well as the increasing of the wireless connectivity coverage. Due to the large exploration of the area and the steady advance of CMOS technologies, new sensing modules such as cameras have being developed and embedded into low cost transceivers. The interconnection of multiple media sources raised a new technology known as Wireless Multimedia Sensor Networks. These networks allow the development of a wide range of applications that were not possible before using only scalar sensors, especially in areas related to traffic control, surveillance, home automation, and health care. This dissertation explores this new technology for the development of an infrastructure that provides services to semi-autonomous mobile robots in environments instrumented for accessibility, in order to assist the accomplishment of the robot's goals / Mestrado / Engenharia de Computação / Mestre em Engenharia Elétrica
225

Avaliação do desempenho de um rede de sensores sem fio no cultivo de cana-de-açúcar = Assessing the performance of a wireless sensor network in the cultivation of cane sugar / Assessing the performance of a wireless sensor network in the cultivation of cane sugar

Rosa Filho, Luiz Fernando, 1984- 07 May 2012 (has links)
Orientador: Leonardo Lorenzo Bravo Roger / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-20T22:40:50Z (GMT). No. of bitstreams: 1 RosaFilho_LuizFernando_M.pdf: 3503905 bytes, checksum: c6170ff191326cb2408381ac1d7ba35d (MD5) Previous issue date: 2012 / Resumo: Esta dissertação descreve os procedimentos para instalação, configuração e utilização de uma RSSF em cultivo de Cana-de-Açúcar enfatizando o conceito de Agricultura de Precisão. O foco do trabalho foi identificação das distâncias e posicionamento dos elementos da rede de modo a diminuir o número de elementos que garantam uma maior cobertura possível da rede, mantendo um funcionamento adequado nesse tipo de aplicação. Contudo, possibilita-se uma diminuição de custo para implantação e viabilização da utilização de tecnologia de Redes de Sensores Sem Fio em cultivo da Cana-de-Açúcar. O gerenciamento adotado para a Rede de Sensores Sem Fio foi abordagem requisição e resposta (RR) e modo de energia de Alta Potencia (HP). Foi avaliado experimentalmente que no cultivo de Cana-de-Açúcar o desempenho de uma RSSF com topologia estrela na camada sorvedouro e nós sensores é superior à topologia em malha e recomendamos a Topologia Híbrida também chamada em Árvore para esse tipo de aplicação da RSSF. Também no importante quesito de consumo de bateria os experimentos mostraram que o modo requisição resposta em configuração HP, não é adequado para tempos na ordem de 2 minutos, deixando aos administradores das redes e aos agricultores deste tipo de cultivo a definição de um tempo adequado de programação das requisições e respostas nos motes / Abstract: This paper describes the processes for installation, configuration and use of a WSN in sugar cane emphasizing the concept of Precision Agriculture. The focus of the study was to identify the distances and positioning of the network elements so as to reduce the number of elements that can ensure better coverage of the network, maintaining a proper functioning of this type of application. However, it allows a decrease in cost for deployment and use of technology the Wireless Sensor Networks in the cultivation of sugar cane. The management adopted for Wireless Sensor Network approach is Request and Response (RR) in Mode Energy Power High (HP). Was evaluated experimentally that in cultivation of sugar cane, the performance of a WSN with star topology between sorvedouro and sensor nodes is best than the mesh topology and is recommend a hybrid topology or tree topology for this kind of application of WSN. Also in the item important battery-consumer this application, experiments have shown that the Mode Power High, setting Request Response, is not suitable for times 2 in 2 minutes , leaving the network administrators and farmers such cultivation defining a timing of scheduling of requests and responses in the motes / Mestrado / Tecnologia e Inovação / Mestre em Tecnologia
226

Research and implementation of an indoor positioning algorithm

Liu, Honggang January 2017 (has links)
The goal of the Internet of Things’ sensing technology is to provide LBS(location-based services); a key technology is finding out how to positioning the sensing devices. For positioning outdoors, mature tech-nology such as GPS and cellular network location can be used. There is little research about indoor positioning, and there is no finished product on the market. This paper shows how to use both Wi-Fi and ZigBee signal for position-ing; Wi-Fi to find the area position and ZigBee to find the coordinate position. The main contribution of this paper is described in the follow-ing: This paper will present an algorithm using kNN on a Wi-Fi signal, as a way to find the location area of users. The GPS signal cannot be used indoors, but there are usually numerous Wi-Fi signals, that can be used for indoor positioning. In this design, to build a dataset containing the number of locations and the Wi-Fi signal strength list of each location. When indoor positioning is needed, the KNN algorithm is used to compare the user’s Wi-Fi signal strength with the dataset and find the location number. When precise positioning is needed, the ZigBee signal should be used. In this paper two different methods for precise positioning in are used, one is an improved algorithm of triangle centroid algorithm where the positioning accuracy depends on the number of anchor points and the interval of each point. The other method is the neural network method. This method could give stable result with only four anchor points. Finally, there is a comparison of the methods mentioned in this paper : the Wi-Fi fingerprint method, the ZigBee triangle centroid algorithm, and neural network method.
227

A COMPOSITE APPROACH TO DEAL WITH LOCALIZATION PROBLEMS IN WIRELESS SENSOR NETWORK

Rao, Shehryar January 2010 (has links)
Universal algorithm approach is very a unique and quite useful. It can be used for most of the localization problems. A number of research studies have been taken to evaluate the different algorithms. The literature review and surveys are the key sources to get the resultant algorithm. This thesis addresses different kind of localization problems and provides a universal solution for these problems. I have done a very important literature review and some industry based surveys. The result of surveys and literature review was a bit same, so it was quite easy to find solution for those similar problems. The idea behind this universal solution is very simple. I chose two algorithms which were quite useful in the localization and merge. The resultant algorithm proves more useful than other two algorithms. The author finds it very healthy and useful algorithm. Moreover, there is need to improve some aspects. There is need to implement this algorithm practically. Some sort of professional skills are required to make this algorithm worthy.
228

Enabling communication between border router and 6LoWPAN-based WSN for Healthcare

LI, XUEYUN January 2011 (has links)
No description available.
229

Model-Based Heterogeneous Data Fusion for Reliable Force Estimation in Dynamic Structures under Uncertainties

Khodabandeloo, Babak, Melvin, Dyan, Jo, Hongki 17 November 2017 (has links)
Direct measurements of external forces acting on a structure are infeasible in many cases. The Augmented Kalman Filter (AKF) has several attractive features that can be utilized to solve the inverse problem of identifying applied forces, as it requires the dynamic model and the measured responses of structure at only a few locations. But, the AKF intrinsically suffers from numerical instabilities when accelerations, which are the most common response measurements in structural dynamics, are the only measured responses. Although displacement measurements can be used to overcome the instability issue, the absolute displacement measurements are challenging and expensive for full-scale dynamic structures. In this paper, a reliable model-based data fusion approach to reconstruct dynamic forces applied to structures using heterogeneous structural measurements (i.e., strains and accelerations) in combination with AKF is investigated. The way of incorporating multi-sensor measurements in the AKF is formulated. Then the formulation is implemented and validated through numerical examples considering possible uncertainties in numerical modeling and sensor measurement. A planar truss example was chosen to clearly explain the formulation, while the method and formulation are applicable to other structures as well.
230

A Diagnostic Tool for the Causes of Packet Corruption in Wireless Sensor Networks

Jiang, Wenxuan January 2015 (has links)
The two main causes of packet corruption in wireless sensor network are multipath fading and WiFi interference. Identifying the cause of the corruption can be used to improve the reliability of the transmission. If the corruption is caused by WiFi interference, the network could change the channel to a free one. If it is caused by multipath fading, the network could reroute the traffic away from the obstacles or shorten the distance. This project proposes a new method of corruption-causes-identification for the two causes mentioned. It is an immediate online diagnostic tool for IEEE 802.15.4 packets with a retransmission mechanism. It provides a statistical boundary with a processed deviation of RSSI value and the frame symbol error rate, and also a rechecking mechanism to check the decisions. In this model, the deviation of RSSI value is measured by the estimated RSSI value of correct packets and the current detected RSSI value. The benefit of the deviation design is that the statistical model hardly needs to retrain and correct the parameters in different transmission environments. The project also discusses two rechecking mechanism methods, one employs an individual secondary classification with its own characters; the other combines the neighbor packets' features to smooththe probable errors. To investigate the performance of the "frame symbol errorrate and deviation of RSSI values"-based diagnostic tool, the evaluation parts provide a comparison of different length packets. The conclusion is that this diagnostic tool provides a correct judgment of the accuracy of packet corruption caused by multipath fading up to 98.70%, and an accuracy of up to 92.99% for the WiFi-interferenced packet corruption.

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