Aplicação de Internet of Things em casas inteligentes: Serviços de Rede

O foco principal no estudo da Internet of Things tem sido a integração de dispositivos digitais com o mundo físico e vice-versa. Os dispositivos inteligentes têm vindo a ganhar uma forte presença na nossa vida diária e cada vez mais, tendem a integrar o sistema de uma casa, automatizando processos comuns como o controlo de temperatura ambiente ou mesmo a percentagem de luminosidade de uma divisão. A visão da IoT contempla um mundo interconectado, recolhendo informações de forma automática e possibilitando a comunicação entre dispositivos. Contudo, as tecnologias existentes para a criação de redes que albergam estes novos dispositivos carecem de padrões bem definidos, dificultando a interoperabilidade entre as diversas soluções existentes. Neste projeto são estudadas e aplicadas as tecnologias mais promissoras aplicáveis ao paradigma Internet of Things, com o objetivo de encontrar um conjunto de protocolos padrão para a implementação de sistemas de automação em casas inteligentes.1 Como objetivo final deste projeto, pretende-se criar uma rede de dispositivos com capacidades sensoriais que tenham a capacidade de comunicar com o mundo externo, permitindo o acesso à rede por qualquer tipo de utilizador. Com isso, espera-se caminhar para mais perto da padronização dos protocolos inerentes à IoT e habilitar interoperabilidade entre as mais diversas soluções. São apresentados e utilizados os protocolos que mais se adaptam ao tema escolhido, tentando simplificar a rede para que esta possa ser incluída em qualquer ambiente doméstico, recorrendo a hardware de custo reduzido. Os protocolos apresentados são o 6LoWPAN, utilizando o protocolo IEEE 802.15.4 como interface de rede juntamente com endereçamento IPv6. É também utilizado o protocolo CoAP na troca de mensagens entre os dispositivos.

Sensor Integration for Smart Cities Using Multi-Hop Networks

Smart Cities are designed to be living systems and turn urban dwellers life more comfortable and interactive by keeping them aware of what surrounds them, while leaving a greener footprint. The Future Cities Project [1] aims to create infrastructures for research in smart cities including a vehicular network, the BusNet, and an environmental sensor platform, the Urban Sense. Vehicles within the BusNet are equipped with On Board Units (OBUs) that offer free Wi-Fi to passengers and devices near the street. The Urban Sense platform is composed by a set of Data Collection Units (DCUs) that include a set of sensors measuring environmental parameters such as air pollution, meteorology and noise. The Urban Sense platform is expanding and receptive to add new sensors to the platform. The parnership with companies like TNL were made and the need to monitor garbage street containers emerged as air pollution prevention. If refuse collection companies know prior to the refuse collection which route is the best to collect the maximum amount of garbage with the shortest path, they can reduce costs and pollution levels are lower, leaving behind a greener footprint. This dissertation work arises in the need to monitor the garbage street containers and integrate these sensors into an Urban Sense DCU. Due to the remote locations of the garbage street containers, a network extension to the vehicular network had to be created. This dissertation work also focus on the Multi-hop network designed to extend the vehicular network coverage area to the remote garbage street containers. In locations where garbage street containers have access to the vehicular network, Roadside Units (RSUs) or Access Points (APs), the Multi-hop network serves has a redundant path to send the data collected from DCUs to the Urban Sense cloud database. To plan this highly dynamic network, the Wi-Fi Planner Tool was developed. This tool allowed taking measurements on the field that led to an optimized location of the Multi-hop network nodes with the use of radio propagation models. This tool also allowed rendering a temperature-map style overlay for Google Earth [2] application. For the DCU for garbage street containers the parner company provided the access to a HUB (device that communicates with the sensor inside the garbage containers). The Future Cities use the Raspberry pi as a platform for the DCUs. To collect the data from the HUB a RS485 to RS232 converter was used at the physical level and the Modbus protocol at the application level. To determine the location and status of the vehicles whinin the vehicular network a TCP Server was developed. This application was developed for the OBUs providing the vehicle Global Positioning System (GPS) location as well as information of when the vehicle is stopped, moving, on idle or even its slope. To implement the Multi-hop network on the field some scripts were developed such as pingLED and “shark”. These scripts helped upon node deployment on the field as well as to perform all the tests on the network. Two setups were implemented on the field, an urban setup was implemented for a Multi-hop network coverage survey and a sub-urban setup was implemented to test the Multi-hop network routing protocols, Optimized Link State Routing Protocol (OLSR) and Babel.

A multi-objective optimization of the active and reactive resource scheduling at a distribution level in a smart grid context

In the traditional paradigm, the large power plants supply the reactive power required at a transmission level and the capacitors and transformer tap changer were also used at a distribution level. However, in a near future will be necessary to schedule both active and reactive power at a distribution level, due to the high number of resources connected in distribution levels. This paper proposes a new multi-objective methodology to deal with the optimal resource scheduling considering the distributed generation, electric vehicles and capacitor banks for the joint active and reactive power scheduling. The proposed methodology considers the minimization of the cost (economic perspective) of all distributed resources, and the minimization of the voltage magnitude difference (technical perspective) in all buses. The Pareto front is determined and a fuzzy-based mechanism is applied to present the best compromise solution. The proposed methodology has been tested in the 33-bus distribution network. The case study shows the results of three different scenarios for the economic, technical, and multi-objective perspectives, and the results demonstrated the importance of incorporating the reactive scheduling in the distribution network using the multi-objective perspective to obtain the best compromise solution for the economic and technical perspectives.

Message-oriented middleware for smart grids

In order to increase the efficiency in the use of energy resources, the electrical grid is slowly evolving into a smart(er) grid that allows users' production and storage of energy, automatic and remote control of appliances, energy exchange between users, and in general optimizations over how the energy is managed and consumed. One of the main innovations of the smart grid is its organization over an energy plane that involves the actual exchange of energy, and a data plane that regards the Information and Communication Technology (ICT) infrastructure used for the management of the grid's data. In the particular case of the data plane, the exchange of large quantities of data can be facilitated by a middleware based on a messaging bus. Existing messaging buses follow different data management paradigms (e.g.: request/response, publish/subscribe, data-oriented messaging) and thus satisfy smart grids' communication requirements at different extents. This work contributes to the state of the art by identifying, in existing standards and architectures, common requirements that impact in the messaging system of a data plane for the smart grid. The paper analyzes existing messaging bus paradigms that can be used as a basis for the ICT infrastructure of a smart grid and discusses how these can satisfy smart grids' requirements.

mRPL: Boosting mobility in the Internet of Things

The 6loWPAN (the light version of IPv6) and RPL (routing protocol for low-power and lossy links) protocols have become de facto standards for the Internet of Things (IoT). In this paper, we show that the two native algorithms that handle changes in network topology – the Trickle and Neighbor Discovery algorithms – behave in a reactive fashion and thus are not prepared for the dynamics inherent to nodes mobility. Many emerging and upcoming IoT application scenarios are expected to impose real-time and reliable mobile data collection, which are not compatible with the long message latency, high packet loss and high overhead exhibited by the native RPL/6loWPAN protocols. To solve this problem, we integrate a proactive hand-off mechanism (dubbed smart-HOP) within RPL, which is very simple, effective and backward compatible with the standard protocol. We show that this add-on halves the packet loss and reduces the hand-off delay dramatically to one tenth of a second, upon nodes’ mobility, with a sub-percent overhead. The smart-HOP algorithm has been implemented and integrated in the Contiki 6LoWPAN/RPL stack (source-code available on-line mrpl: smart-hop within rpl, 2014) and validated through extensive simulation and experimentation.

Feature Extraction in Densely Sensed Environments: Extensions to Multiple Broadcast Domains

The vision of the Internet of Things (IoT) includes large and dense deployment of interconnected smart sensing and monitoring devices. This vast deployment necessitates collection and processing of large volume of measurement data. However, collecting all the measured data from individual devices on such a scale may be impractical and time consuming. Moreover, processing these measurements requires complex algorithms to extract useful information. Thus, it becomes imperative to devise distributed information processing mechanisms that identify application-specific features in a timely manner and with a low overhead. In this article, we present a feature extraction mechanism for dense networks that takes advantage of dominance-based medium access control (MAC) protocols to (i) efficiently obtain global extrema of the sensed quantities, (ii) extract local extrema, and (iii) detect the boundaries of events, by using simple transforms that nodes employ on their local data. We extend our results for a large dense network with multiple broadcast domains (MBD). We discuss and compare two approaches for addressing the challenges with MBD and we show through extensive evaluations that our proposed distributed MBD approach is fast and efficient at retrieving the most valuable measurements, independent of the number sensor nodes in the network.

Measuring data transfer in heterogeneous IoT environments

Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores

Profiling of real-world web applications

Dissertação para obtenção do Grau de Mestre em Engenharia Informática

Impacto da introdução de baterias de armazenamento de energia em Smart Grids

De forma a não comprometer o conforto ou a qualidade de vida, nos dias de hoje, é obrigatório que a energia elétrica esteja presente. Sendo indispensável, torna-se necessário assegurar que a sua distribuição seja feita da forma mais eficiente possível. Uma resposta rápida e eficaz a possíveis falhas que ocorram na rede, irá garantir a tal qualidade de serviço desejada. Para isso, a automatização dos processos é uma grande evolução e objetivo de concretização do setor elétrico. Neste contexto surge o conceito de Smart Grid, que tem como principal objetivo a combinação entre o setor elétrico e a evolução da tecnologia. A par desta característica, estes tipos de redes vêm também trazer evoluções no âmbito ambiental, pois a produção de energia elétrica é feita, maioritariamente, por fontes de energia renovável. Este projeto incide na análise das vantagens técnicas e económicas da inclusão de equipamentos que detêm capacidades de armazenamento de energia, as Baterias de Armazenamento de Energia (BAE), neste tipo de redes. Neste estudo foi usado o método do Despacho Económico, que tem como principal objetivo a determinação dos níveis de produção de todas as unidades geradoras do sistema ao mais baixo custo de produção, satisfazendo a carga. Com recurso a este método, foram criados vários cenários de estudo com vista a validar o estudo apresentado neste artigo. Neste artigo é também realizado um estudo de viabilidade económica destes equipamentos de armazenamento de energia.

Interfaces com o utilizador em sistemas de informação web

A crescente quantidade de informação com que se depara a sociedade tem vindo a fomentar a necessidade de auto-formação quer em meios empresariais, quer em instituições vocacionadas para a educação. Atcualmente, essa auto-formação recorre tendencialmente cada vez mais, a processos Multimédia e de Internet World Wide Web, visto estes permitirem a ausência do utilizador dos locas tradicionais de divulgação de informação. Por outro lado, as empresas e demais instituições poderão encontrar nestes recursos, uma forma privilegiada de redução de custos e de abrangência de utilizadores de segmentos geográficos e culturais longínquos.

A Web como suporte à aprendizagem

O presente trabalho tem por objectivo abordar as questões mais relevantes envolvidas na problemática da Web como suporte à aprendizagem. No trabalho aborda-se o papel da Web na aprendizagem, as suas implicações e aspectos a ter em conta. São ainda abordadas as ferramentas e meios disponíveis para realizar aprendizagem com base na Web, sendo fornecidos exemplos paradigmáticos. Dificuldades ligadas ao tema são explanadas e algumas tendências futuras referidas. Por fim são equacionadas algumas questões em aberto.

SMART PANEL: medição, controlo e monitorização num clique

Na sociedade atual, a preocupação com o ambiente, por um lado, e com o conforto e a segurança, por outro, faz com que a sustentabilidade energética se assuma como uma forma de intervenção adequada às exigências de qualidade de vida e à eficiência no âmbito da economia. Nesta conformidade, é incontornável a mais-valia do Smart Panel, um quadro elétrico inteligente criado pela Schneider-Electric com vista à consecução daqueles desideratos. Iremos abordar, neste artigo, a gama de produtos que perfazem esta tecnologia, fazendo uma breve descrição de cada um deles, expondo de seguida um exemplo de aplicação desta tecnologia. Numa fase posterior apresentaremos as vantagens do Smart Panel face à tecnologia tradicional (até hoje a mais comum) no que respeita ao controlo de um quadro elétrico, Sistema de Gestão Técnica Centralizada.

SHõWA: A Self-healing Framework for Web-based Applications

The complexity of systems is considered an obstacle to the progress of the IT industry. Autonomic computing is presented as the alternative to cope with the growing complexity. It is a holistic approach, in which the systems are able to configure, heal, optimize, and protect by themselves. Web-based applications are an example of systems where the complexity is high. The number of components, their interoperability, and workload variations are factors that may lead to performance failures or unavailability scenarios. The occurrence of these scenarios affects the revenue and reputation of businesses that rely on these types of applications. In this article, we present a self-healing framework for Web-based applications (SHõWA). SHõWA is composed by several modules, which monitor the application, analyze the data to detect and pinpoint anomalies, and execute recovery actions autonomously. The monitoring is done by a small aspect-oriented programming agent. This agent does not require changes to the application source code and includes adaptive and selective algorithms to regulate the level of monitoring. The anomalies are detected and pinpointed by means of statistical correlation. The data analysis detects changes in the server response time and analyzes if those changes are correlated with the workload or are due to a performance anomaly. In the presence of per- formance anomalies, the data analysis pinpoints the anomaly. Upon the pinpointing of anomalies, SHõWA executes a recovery procedure. We also present a study about the detection and localization of anomalies, the accuracy of the data analysis, and the performance impact induced by SHõWA. Two benchmarking applications, exercised through dynamic workloads, and different types of anomaly were considered in the study. The results reveal that (1) the capacity of SHõWA to detect and pinpoint anomalies while the number of end users affected is low; (2) SHõWA was able to detect anomalies without raising any false alarm; and (3) SHõWA does not induce a significant performance overhead (throughput was affected in less than 1%, and the response time delay was no more than 2 milliseconds).

Comunicação estratégica digital. Otimização das estratégias comunicacionais através de novas plataformas sociais na web

Trabalho de Projeto apresentado para o cumprimento dos requisitos necessários à obtenção de grau de Mestre em Novos Media e Práticas Web

Reconfiguração dinâmica estruturada de workflows de serviços web

Dissertação para obtenção do Grau de Mestre em Engenharia Informática