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Posicionamento de m?ltiplos Sinks em redes de sensores sem fio com prioriza??oPeixoto, Jo?o Paulo Just 15 December 2015 (has links)
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Previous issue date: 2015-12-15 / Wireless Sensor Networks can be used for environment monitoring, which may be in indoor scenarios such as in industries, warehouses and buildings, or in outdoor scenarios, just like forests, vulcanos and cities. Due to its energy supply limitations, researchers have been developing several approaches to reduce energy consumption
in sensors and extend their lifetime. One of the ways to improve energy usage in a Wireless Sensor Network is by using multiple mobile sinks. In this work, a method to position multiple sinks in a relevance-based Wireless Sensor Network is proposed. After several simulations, it was observed that in applications where
sensors have di erent importance levels, the network lifetime can be extended by using this approach. / Redes de Sensores Sem Fios podem ser utilizadas para o monitoramento de ambientes, sejam eles internos como ind ?strias, galp?es, constru??ess, ou externos como florestas, vulc?es, cidades, entre outros. Devido a sua limita ??o no fornecimento de energia, pesquisadores tem desenvolvido diversas abordagens para reduzir o consumo energ?tico nos sensores e prolongar seu tempo de vida. Uma das formas de melhorar o consumo de energia em uma Rede de Sensores Sem Fios e atrav?s do uso de m ?ltiplos sinks m oveis. Neste trabalho, e proposto um m ?todo para posicionamento de m ?ltiplos sinks em uma Rede de Sensores Sem Fios baseada em relev?ncias. Ap ?s diversas simula ??es, foi observado que em aplica ??es onde sensores possuem diferentes ni veis de import?ncia, o uso dessa abordagem aumenta o tempo de vida da rede.
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On information-centric routing and forwarding in the internet of things / Du routage centré contenu pour l'internet des objetsEnguehard, Marcel 15 April 2019 (has links)
Les réseaux centrés contenus (ICN) sont considérés comme une solution aux nouveaux défis et modes de communication liés à l'émergence de l'Internet des Objets (IoT). Pour confirmer cette hypothèse, la problématique fondamentale du routage sur les réseaux ICN-IoT doit être abordée. Cette thèse traite de ce sujet à travers l'architecture IoT.Premièrement, une méthode sécurisée est introduite pour acheminer des paquets ICN à partir de coordonnées géographiques dans un réseau sans-fil de capteurs à faible puissance. Elle est comparée à une inondation optimisée du réseau inspirée des approches existant dans la littérature. En particulier, leur faisabilité et passage à l'échelle sont évalués via un modèle mathématique. Le modèle est paramétré grâce à des données réalistes issues de simulation, de la littérature, et d'expériences sur des capteurs. Il est montré que le routage géographique permet de diviser la mémoire nécessaire sur les capteurs par deux et de réduire considérablement le coût énergétique du routage, en particulier pour des topologies dynamiques.Ensuite, ICN est utilisé pour contrôler l'admission à une plate-forme de calcul de type Fog afin de garantir le temps de réponse. La stratégie de contrôle d'admission proposée, le LRU-AC, utilise l'algorithme Least-Recently-Used (LRU) pour apprendre en direct la distribution de popularité des requêtes. Son efficacité est démontrée grâce à un modèle fondé sur un réseau de files d'attente. Une implémentation du LRU-AC est proposé, utilisant des filtres de Bloom pour satisfaire aux contraintes des cartes FPGA. Son bien-fondé est prouvé par un modèle mathématique et son efficacité en termes de latence et débit démontrée.Enfin, on présente vICN, un outil pour la gestion et la virtualisation de réseaux ICN-IoT. Il s'agit d'une plate-forme qui unifie la configuration et la gestion des réseaux et des applications en exploitant les progrès des techniques d'isolation et de virtualisation. vICN est flexible, passe à l'échelle, et peut remplir différents buts : expériences à grande échelle reproductibles pour la recherche, démonstrations mélangeant machines émulées et physiques, et déploiements réels des technologies ICN dans les réseaux IP existants. / As the Internet of Things (IoT) has brought upon new communication patterns and challenges, Information-Centric Networking (ICN) has been touted as a potential solution. To confirm that hypothesis, the fundamental issue of routing and forwarding in the ICN-IoT must be addressed. This thesis investigates this topic across the IoT architecture.First, a scheme to securely forward ICN interests packets based on geographic coordinates is proposed for low-power wireless sensor networks (WSN). Its efficiency is compared to an optimized flooding-based scheme similar to current ICN-WSN approaches in terms of deployability and scalability using an analytical model. Realistic data for the model is derived from a mixture of simulation, literature study, and experiments on state-of-the-art sensor boards. Geographic forwarding is shown to halve the memory footprint of the ICN stack on reference deployments and to yield significant energy savings, especially for dynamic topologies. Second, ICN is used to enhance admission control (AC) to fixed-capacity Edge-computing platforms to guarantee request-completion time for latency-constrained applications. The LRU-AC, a request-aware AC strategy based on online learning of the request popularity distribution through a Least-Recently-Used (LRU) filter, is proposed. Using a queueing model, the LRU-AC is shown to decrease the number of requests that must be offloaded to the Cloud. An implementation of the LRU-AC on FPGA hardware is then proposed, using Ageing Bloom Filters (ABF) to provide a compact memory representation. The validity of using ABFs for the LRU-AC is proven through analytical modelling. The implementation provides high throughput and low latency.Finally, the management and virtualization of ICN-IoT networks are considered.vICN (virtualized ICN), a unified intent-based framework for network configuration and management that uses recent progress in resource isolation and virtualization techniques is introduced. It offers a single, flexible and scalable platform to serve different purposes, ranging from reproducible large-scale research experimentation to demonstrations with emulated and/or physical devices and network resources and to real deployments of ICN in existing IP networks.
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IoT Latency and Power consumption : Measuring the performance impact of MQTT and CoAPLagerqvist, Alexander, Lakshminarayana, Tejas January 2018 (has links)
The purpose of this thesis is to investigate the impact on latency and power consumption of certain usage environments for selected communication protocols that have been designed for resource constrained usage. The research questions in this thesis is based on the findings in Lindén report “A latency comparison of IoT protocols in MES” and seeks to answer the following: ”How does MQTT impact the latency and power consumption on a constrained device?” ”How does CoAP impact the latency and power consumption on a constrained device?” ”How does usage environment influence the latency for MQTT and CoAP?” This thesis only seeks to explore concepts and usage environments related to wireless sensor networks, internet of things and constrained devices. The experiments have been carried out on a ESP WROOM 32 Core board V2 applying MQTT and CoAP as the communication protocols. The overall research method used in this thesis is the experimental research design proposed by Wohlin et al. Experiments have been created to support or disprove hypotheses which are formulated to answer the research questions. The experiments were conducted in test environments, which mimic a real-life wireless sensor network environment. The process is thoroughly recorded to further increase the traceability of this thesis. This decision was made due to a comment Boyle et al. made about the problems with real-life experiments about the wireless communication-based research domain. Where Boyle et al. states that there is “insufficient knowledge” available for the research community. The MQTT related latency experiments showed that QoS level 0 had the lowest latency of all the QoS levels. However, the results also showed that QoS 1 and 2 almost had an identical latency. The CoAP related latency experiments did not indicate any obvious trends. The results from the power consumption related experiments were inconclusive since the data was incomplete. The usage environment related experiments yielded conclusive results. The data showed that there was a small variation in the latency impact across the various usage environments. Furthermore, the data suggest that CoAP and MQTT had lower latencies in a high signal strength environment compared to a lower signal strength environment. However, it is not clear if there were any unknown factors influencing the results.
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Senzorová síť WirelessHART / WirelessHART sensor nodeŘežucha, Tomáš January 2018 (has links)
The master’s thesis is focused on building WirelessHART node demo and on a description of WirelessHART standard, which is used in wireless sensor networks. Out of the comprehensive WirelessHART specifications firstly, the two lowest layers of OSI networking model are described: physical and data link layer. Secondly, burst mode and device variables are described to provide necessary information for data publishing in the network. The mote is assembled according to hardware and software requirements of WirelessHART demo system. The node is complemented by its firmware and PC application demonstrating its features in a user-friendly manner.
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Hromadná komunikace v bezdrátových senzorových sítích / Multicast Communication in Wireless Sensor NetworksValouch, Jaromír January 2009 (has links)
This master’s thesis describes energy consumption in wireless sensor networks. It is focused on energy consumption during communication and it provides rules to save energy during this operation. There are terms like wireless sensor networks, multicast, ad-hoc networks, routing protocols, multicast routing protocols, IGMP protocol, AODV routing protocol, MAODV routing protocol explained in this thesis. The main difference between multicast and unicast communication is analyzed as well. In the end of this thesis there are results of simulation small wireless sensor network from network simulator2. The simulations were focused on energy consumption during communication. The length of packet was changed during communication between two nodes in this simulation. In wireless sensors network nodes play a dual role as both data sender and data router therefore there were made research into energy consumption senders, routers, receivers in wireless sensor network during communication.
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Model bezdrátové senzorové sítě realizovaný v nástroji J-Sim / Wireless Sensor Network Simulation Model in J-Sim ToolVrzal, Tomáš January 2010 (has links)
This thesis deals with the issue of wireless sensor networks and communication protocols. Is explained of what the network is composed, what standards are used and in what sectors are most often used. The main scope of work is to introduce with the localization algorithms using in WSN. Algorithms are clearly divided into groups according to the methods used. In work is describes the structure used simulation tools J-Sim, for creating a wireless sensor network. To create network will be then applied different localization algorithms, which must first be implemented in a simulator using Java code. All generated classes and the algorithms are detailed described in the work. Results from simulations are detailed and graphically displays for individual localization algorithms.
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Snížení chyby odhadu pozice u inkrementálních lokalizačních technik / Reduction of position estimate error in incremental localization techniquesPekárek, Jan January 2011 (has links)
The diploma thesis describes localization of communications nodes in the Wireless Sensor Networks. This thesis contains basic algorithms for localization sensor's nodes as are Map-Growing and ABC (Assumption Based Coordinates). Then is chosen acceptable algorithm for simulation on random sensor networks. For research these problems is used software MATLAB. For a given the university's environment are researched appropriate algorithms with possible optimalization algorithms. The result of diploma thesis is a localization algorithm with initial multilateration system and this system is located in the center sensor's network. As algorithm IMap4-Growing (Improved Map4-Growing) with optimization, which uses optimization distance between sensors and radio range. In the diploma thesis is simulated optimalization algorithm Mass-Spring.
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Návrh paketového analyzátoru pro UWB pásmo dle standardu IEEE 802.15.4a / Packet Analyser for UWB based on 15.4a standardLeixner, Martin January 2014 (has links)
The aim of this work is study the standard for wireless sensor networks IEEE 802.15.4a. Design and implementation of a packet analyzer for ultra wideband technology com- pliant with IEEE 802.15.4a standard. Integrate packet analyzer to inspection software Wireshark and implement dissector for view packets. Finally, analyze and evaluate the parameters of the proposed packet analyzer.
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Lokalizační služby ve webových aplikacích / Localization Services for Web ApplicationsKočan, Tomáš January 2015 (has links)
The aim of this master thesis was to develop an application that would visualize the position of sensors placed indoors. Since the sensors are located in the buildings, geographical maps are not used as basis, but the user has the option to upload his own background in the form of floor plans of rooms, floors, buildings,... For this purpose, application has tools for uploading, managing and editing such plans. The paper also describes how to use the application to monitor the current and past positions of these sensors. Support for these features is provided by several server components consisting of a REST server, WebSocket server, Upload servers and other services. Their design, description, and implementation is also part of this document. In addition, the work describes RTLS (Real-time locating system) technology, architecture, client application and data security.
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Estudo da colheita de energia para medição de vazão em aplicações de internet das coisas /Machado Junior, Ireno Gonçalves January 2020 (has links)
Orientador: Eduardo Paciência Godoy / Resumo: A colheita de energia emerge como uma das soluções para a alimentação sustentável de sensores e dispositivos de monitoramento em redes sem fio nas aplicações da Internet das Coisas (IoT), permitindo até mesmo prescindir do uso de baterias. Este trabalho descreve o desenvolvimento de uma plataforma de colheita de energia e monitoramento de vazão a partir de redes de distribuição hidráulicas. O sistema experimental montado apresenta um circuito fechado de fluxo variável de água, criado a partir de uma bomba pressurizadora controlável eletronicamente, com sensor de vazão e um micro hidrogerador. A energia elétrica recuperada através do micro hidrogerador é utilizada para alimentar diferentes dispositivos de IoT com comunicação via Wi-Fi dos dados de monitoramento da vazão e volume, assim como, fornece energia para baterias. Os testes operacionais tiveram como objetivo dimensionar a quantidade de energia recuperada, em comparação com a energia consumida pelos dispositivos e bateria conectadas, em função dos valores de vazão obtidos pela plataforma. Nos testes realizados foi possível demonstrar a capacidade da colheita de energia pelo micro hidrogerador, com geração de aproximadamente 1W de energia e sua utilização para a operação contínua de dispositivos em aplicações de IoT. O estudo e implantação de diferentes modos de operação para os dispositivos medidores de vazão possibilitaram a redução do consumo de energia em até 54,4% e maximizaram a eficiência energética da solução, co... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Energy harvesting emerges as one of the solutions for sustainable power supply of sensors and monitoring devices in wireless networks in the Internet of Things (IoT) applications, even allowing to dispense with the use of batteries. This work describes the development of an energy harvesting and flow monitoring platform from hydraulic distribution networks. The assembled experimental system features a variable water flow closed loop, created from an electronically controllable pressurizing pump with flow sensor and a micro hydrogenerator. The electrical energy recovered through the micro-generator supplies different IoT device models with Wi-Fi communication of the flow and volume monitoring data and also provides power for storage batteries. The operational tests aimed to measure the amount of energy recovered, compared to the energy consumed by the connected devices and battery, according to the flow values obtained by the platform. In the tests carried out it was possible to demonstrate the capacity to harvest energy by the micro-generator, generating approximately 1W of energy and its use for the continuous operation of devices in IoT applications. The study and implementation of different modes of operation for flow meter devices make it possible to reduce energy consumption by up to 54.4% and maximize the energy efficiency of the solution, proving the potential of energy recovery as a viable alternative to guarantee the operation of self-sustaining meters for IoT applic... (Complete abstract click electronic access below) / Mestre
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