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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.
601

Uma arquitetura baseada em internet das coisas para rastreabilidade da cadeia de suprimentos do vinho. / An internet of things-based architecture for traceability of the wine supply chain.

Leonardo Barreto Campos 14 December 2017 (has links)
A próxima geração da Internet aponta para um cenário onde trilhões de pessoas e objetos estarão interconectados e acessíveis a qualquer momento e em qualquer lugar. Um dos pilares desta nova geração é o paradigma conhecido como Internet das Coisas, que tem atraído pesquisas em diferentes domínios, entre eles, saúde, indústria, logística, cidades inteligentes, casas inteligentes e agronegócio. No contexto do agronegócio, a Internet das Coisas tem avançado em aplicações de rastreabilidade das cadeias de suprimentos com produtos de alto valor agregado, por exemplo, a cadeia do vinho. Entretanto, o desenvolvimento de aplicações para rastreabilidade dessa cadeia não está suportado por uma arquitetura baseada em Internet das Coisas. Além disso, os sistemas de rastreabilidade das cadeias de suprimentos atuais não contemplam amplamente o paradigma da Internet das Coisas em sua premissa de interconexão entre os agentes da cadeia. Dessa forma, esta tese propõe uma arquitetura em camadas baseada no paradigma de Internet das Coisas para rastreabilidade da cadeia de suprimentos do vinho. Para isso foi realizado o levantamento de requisitos, a identificação dos interessados no sistema (stakeholders) suas preocupações, identificação dos atributos de qualidade e a relevância de cada um deles. De posse de uma arquitetura candidata foi implementado um sistema em um caso real para refinamento dos componentes da arquitetura. A avaliação da arquitetura proposta em diferentes parâmetros mostra sua adequação tanto ao paradigma de Internet das Coisas quanto às necessidades dos stakeholders da cadeia de suprimentos do vinho. Dessa forma é possível afirmar que os sistemas implementados a partir da arquitetura proposta tendem a ser escaláveis, seguros, adaptativos, disponíveis e que suportam a interconexão entre os agentes da cadeia de suprimentos, desde a produção do vinho até o seu descarte. / The next-generation Internet points to a scenario where trillions of objects and people are interconnected and accessible anytime and anywhere. One of the pillars of this new generation is the paradigm known as Internet of Things. This paradigm has attracted research in different domains, including, health, industry, logistics, smart cities, smart homes and agribusiness. In the context of agribusiness, the Internet of Things has advanced in applications of traceability of supply chains with products of high added value, for example, the wine chain. However, the development of applications for traceability in the wine supply chain is not supported by an architecture Internet of Things-based. In addition, current supply chain traceability systems do not broadly address the Internet of Things paradigm in its premise of interconnection among chain agents. Thus, this thesis proposes a layered architecture based on the Internet of Things paradigm for traceability of the wine supply chain. To do this, requirements were surveyed, the identification of the stakeholders in the system their concerns, identification of quality attributes and the relevance of each one of them. A candidate system was implemented in a real case for the refinement of architectural components. The evaluation of the architecture proposed in different parameters shows its adequacy both to the Internet paradigm of Things and to the needs of the stakeholders of the wine supply chain. In this way it is possible to affirm that the systems implemented from the proposed architecture are scalable, secure, adaptive, available and that support the interconnection between the agents of the supply chain, from its wine production to its disposal.
602

A proposal for an integrated framewoek capable of aggregating IoT data with diverse data types. / Uma proposta de um framework capaz de agregar dados de IoT com diversos tipos de dados.

Maria Luisa Lopes de Faria 30 March 2017 (has links)
The volume of information in the Internet is growing exponentially. The ability to find intelligible information among vast amounts of data is transforming the human vision of the universe and everything within it. The underlying question then becomes which methods or techniques can be applied to transform the raw data into something intelligible, active and personal? This question is explored in this document by investigating techniques that improve intelligence for systems in order to make them perceptive/active to the recent information shared by each individual. Consequently, the main objective of this thesis is to enhance the experience of the user (individual) by providing a broad perspective about an event, which could result in improved ideas and better decisions. Therefore, three different data sources (individual data, sensor data, web data) have been investigated. This thesis includes research into techniques that process, interpret and reduce these data. By aggregating these techniques into a platform it is possible to deliver personalised information to applications and services. The contribution of this thesis is twofold. First, it presents a novel process that has shifted its focus from IoT technology to the user (or smart citizen). Second, this research shows that huge volumes of data can be reduced if the underlying sensor signal has adequate spectral properties to be filtered and good results can be obtained when employing a filtered sensor signal in applications. By investigating these areas it is possible to contribute to this new interconnected society by offering socially aware applications and services. / Sem resumo
603

Framework formal para composição automática de serviços em sistemas de internet das coisas. / Formal framework for automatic service composition in internet of things system.

André Luís Meneses Silva 01 March 2018 (has links)
É cada vez mais notável o desenvolvimento da indústria micro-eletrônica. A criação de dispositivos eletrônicos menores, que apresentam maior autonomia de energia, aliados ao aumento do poder de processamento, armazenamento e comunicação sem fio de alta velocidade favoreceram o surgimento e disseminação de novas tecnologias e paradigmas, dentre elas a Internet das Coisas (IoT). Do ponto de vista tecnológico, IoT é uma rede de objetos físicos que possuem tecnologia embarcada de sensoriamento e atuação. Agências de consultoria empresarial, tais como a McKinsey & Company, afirmam que IoT apresenta valor de mercado bilionário e poderá ultrapassar a casa dos trilhões antes de 2020. Dessa forma, o mercado de IoT vem se apresentando como um dos mercados mais promissores para os próximos anos. Alguns dos problemas que podem postergar este crescimento são os problemas decorrentes da dificuldade de integração e escalabilidade das aplicações de IoT. Em IoT, problemas de interoperabilidade são corriqueiros, seja pela alta diversidade de dispositivos empregados, seja pela incompatibilidade entre fabricantes. Em relação a escalabilidade, sistemas de IoT possuem uma demanda natural por alta escala, visto que buscam atender demandas comuns a vários setores, seja na indústria, transporte, domótica, segurança pública, comércio, entre outros. Este trabalho apresenta uma solução para esses problemas através do SWoTPAD, um framework formal que auxilia o projetista no desenvolvimento de soluções para IoT. SWoTPAD oferece uma linguagem para especificar dispositivos e serviços, descrever o ambiente e realizar requisições. Adicionalmente, ele gera o módulo de descoberta, composição automática de serviços e execução. Aplicações SWoTPAD são facilmente integráveis, pois usam e estendem um mesmo conjunto de ontologias, o que garante a compatibilidade nos dados gerados e consumidos por essas aplicações. A escalabilidade advém da associação de anotações semânticas a cada um dos elementos que compõem a aplicação de IoT. Essas anotações permitem ao SWoTPAD descobrir, classificar, selecionar e compor automaticamente serviços do ambiente. Dessa forma, SWoTPAD pode procurar por soluções alternativas, quando o serviço original apto a atender uma determinada demanda se encontra sobrecarregado ou indisponível. Para validação do framework, foram adotados dois estudos de caso. O primeiro deles, o problema de implantação de serviços em um ambiente de nuvem, e o segundo, uma aplicação de segurança residencial. O estudo de caso demonstrou que é possível desenvolver aplicações completas de IoT no framework proposto. Adicionalmente, o mecanismo de composição automática gerado pelo framework para essas aplicações apresenta uma piora média de 45% de desempenho quando comparado à composição manual. / The development of the micro-electronics industry is becoming more and more remarkable. The creation of smaller electronic devices, with higher degree of autonomy, processing, storage, and wireless communication favor the emergence and dissemination of new technologies and paradigms, such as the Internet of Things (IoT ). From the technological point of view, IoT is a network of physical objects that have embedded technology of sensing and actuation. McKinsey & Company says the IoT market is already reaching billionaire numbers and may exceed the trillions by 2020. Thus, the IoT market is proving to be one of the most promising markets in the next years. Problems that can delay this growth come from the difficulty of integration and scalability of IoT applications. In IoT, interoperability problems are common, either because of the high diversity of devices used, or because of the incompatibility between manufacturers. Regarding scalability, IoT systems have a natural demand for high scale, since they seek to meet common demands in various sectors, be it in industry, transportation, home automation, public safety, commerce, among others. This work solves these problems through SWoTPAD, a formal framework that assists the designer in developing solutions for IoT. SWoTPAD provides a language for specifying devices and services, describing the environment, and performing requests. Additionally, it generates the discovery, automatic service composition, and execution module. SWoTPAD applications are easily integrable, since they use and extend the same set of ontologies, which guarantees compatibility in the data generated and consumed by these applications. Scalability comes from the association of semantic annotations to each of the elements that compose the IoT application. These annotations allow SWoTPAD to discover, rank, select, and automatically compose services. In this way, SWoTPAD can search for alternative solutions, when the original service able to meet a particular demand is overloaded or unavailable. Two case studies were developed for validation of the framework. The first one, the problem of deploying services in a cloud environment, and the second, a home security system. The case study demonstrated that it is possible to develop complete IoT applications in the proposed framework. Also, the automatic service composition module generated by SWoTPAD for these applications has a mean worsening of 45 % of performance when compared to the manual composition.
604

Um Sistema de Detecção de Intrusão para Detecção de Ataques de Negação de Serviço na Internet das Coisas. / An Intrusion Detection System for Detection of Attacks Service Denial on the Internet of Things.

SOUSA, Breno Fabrício Lira Melo 21 December 2016 (has links)
Submitted by Maria Aparecida (cidazen@gmail.com) on 2017-08-01T15:17:20Z No. of bitstreams: 1 Breno Fabricio.pdf: 3022898 bytes, checksum: d3e376b3280034170ef737c756a8bb30 (MD5) / Made available in DSpace on 2017-08-01T15:17:20Z (GMT). No. of bitstreams: 1 Breno Fabricio.pdf: 3022898 bytes, checksum: d3e376b3280034170ef737c756a8bb30 (MD5) Previous issue date: 2016-12-21 / The paradigm of the Internet of Things (in english, Internet of Things - IoT) came to allow intercommunication between different objects via Internet, and thereby facilitate the form of how the end user will interact with a wide variety of devices that surround him in everyday life. The availability of features that these devices have is a factor that deserves great attention because the use of such resources inappropriately can cause serious damage. Therefore, since such devices are connected to the internet, they are vulnerable to various threats, such as, denial-of-service attack (DoS). In order to tackle DoS type threats in IoT, an Intrusion Detection System (IDS) is proposed for IoT, aiming at detecting some types of DoS attacks. / O paradigma da Internet das Coisas (em inglês, Internet of Things - IoT) surgiu para possibilitar a intercomunicação entre os diferentes objetos através da Internet, e, com isso, facilitar a forma de como o usuário final interagirá com a grande variedade de dispositivos que o cerca no dia a dia. A disponibilidade de recursos que estes dispositivos possuem é um fator que merece uma grande atenção, pois o uso de tais recursos de forma não apropriada pode gerar graves danos. Para tanto, uma vez que tais dispositivos estão conectados à Internet, estes estão vulneráveis a diversas ameaças, como, por exemplo, ataque de negação de serviço (DoS). A fim de enfrentar ameaças do tipo DoS em IoT, propõe-se um IDS (Intrusion Detection System) para IoT, objetivando a detecção de alguns ataques do tipo DoS.
605

Mobilni nadzorni sistemi sa proširenom realnošću i integrisanim industrijskim Internetom stvari / Mobile Supervision Systems With Augmented Reality And Integrated Industrial Internet of Things

Tegeltija Srđan 07 September 2018 (has links)
<p>U disertaciji je predstavljeno istraživanje usmereno ka problemu unapređenja rada postojećih industrijskih SCADA sistema. U fokus istraživanja su postavljeni zadaci klasičnih SCADA sistema kao što su: prikupljanje podataka o postrojenju, skladištenje i analiza podataka, kao i prikaz podataka o postrojenju i na koji način se ovi zadaci mogu unaprediti kroz primenu postojećih mobilnih tehnologija, tehnologija Interneta stvari, kao i tehnologija proširene realnosti. Kao rezultat istraživanja predložen je novi model mobilnih nadzornih sistema sa proširenom realnošću i integrisanim industrijskim Internetom stvari. Predloženi model omogućava realizaciju novih sistema nadzora industrijskih postrojenja baziranih na Industriji 4.0 kao i jednostavnu integraciju u postojeće industrijske sisteme. Predloženi novi model nadzornih sistema je opšti model i njegova velika prednost je univerzalnost i otvorenost za primenu novih mobilnih tehnologija, tehnologija Interneta stvari, kao i tehnologija proširene realnosti. On takođe ima svojsvo fleksibilnosti zato što se može primeniti za različite strukture preduzeća, kao i različite proizvodne procese. Predloženi novi model omogućava sledljivost prikupljenih podataka o industrijskim postrojenjima i proizvodnim procesima dvosmerno, od senzora i aktuatora ka menadžmentu postrojenja, kao i od menadžmenta postrojenja ka senzorima i aktuatorima. Omogućena je implementacija različitih algoritama obrade podataka, nezavisnih od predloženog novog modela nadzornih sistema, sa ciljem detektovanja grešaka ili potencijalnih problema u radu industrijskog postrojenja. Predloženi model omogućava uvid u podatke o postrojenju ne samo licima zaduženim za nadzor i održavanje postrojenja, već i proizvođačima industrijske opreme koji dobijaju informacije o opremi u realnim uslovima omogućavajući unapređenje kvaliteta industrijske opreme. Za analizu i obradu podataka prikupljnih o industrijskom postrojenju i procesu model omogućava implementaciju više algoritama istovremeno, čime je moguće međusobno porediti algoritme sa različitim parametrima obrade podataka.</p> / <p>In this doctoral dissertation, a research oriented to the problem of improvement<br />existing industrial SCADA systems is presented. The research is focused on<br />the tasks of classical SCADA systems such as data acquisition, data storage<br />and analysis, and displays of acquired plant data and how these tasks can be<br />improved by applying existing mobile technologies, Internet technology, and<br />technology of augmented reality. As a result of the research, a new model of<br />mobile supervision systems with augmented reality and integrated industrial<br />Internet of Things was proposed. The proposed model enables the<br />implementation of new supervision systems in industrial plants based on<br />Industry 4.0 concept, as well as simple integration into existing industrial plants.<br />The proposed new model of supervision systems is a general model and its<br />great advantage is the universality and openness to the application of new<br />mobile technologies, the Internet of Things technology, and technology of<br />augmented reality. It also has its own flexibility because it can be applied to<br />different company structures and different production processes. The proposed<br />new model enables the traceability of collected data on industrial plants and<br />production processes in two ways, from sensors and actuators to plant<br />management, as well from plant management to sensors and actuators. It is<br />possible to implement different data processing algorithms, independent of the<br />proposed new model of control systems, with the aim of detecting errors or<br />potential problems in the operation of industrial plants or production processes.<br />The proposed model provides insight into plant data not only for plant<br />monitoring and maintenance personnel but also for industrial equipment<br />manufacturers who receive information on equipment in real-world conditions,<br />enabling improvement of the quality of industrial equipment. For the analysis<br />and processing of data collected on industrial plants and production processes,<br />the proposed model enables the implementation of several algorithms at the<br />same time, thus making it possible to compare different algorithms with different<br />data processing parameters.</p>
606

Standards optimization and network lifetime maximization for wireless sensor networks in the Internet of things / Optimisation de standards et maximisation du temps de vie d'un réseau de capteurs pour l'Internet des objets

Iova, Oana-Teodora 15 December 2014 (has links)
De nouveaux protocoles ont été standardisés afin d'intégrer les réseaux de capteurs sans fil (WSN) dans l'Internet. Parmi eux, RPL pour la couche routage et IEEE 802.15.4 pour la couche MAC. L'objectif de cette thèse est d'améliorer ces protocoles en prenant compte des contraintes énergétiques des dispositifs du WSN. Tout d'abord, nous avons conçu une nouvelle méthode de diffusion dans la norme IEEE 802.15.4, afin d'assurer une livraison fiable des paquets de contrôle des couches supérieures. Ensuite, nous avons fourni une évaluation exhaustive de RPL, en soulignant un problème d'instabilité qui génère une surcharge d'énergie importante. Compte tenu que la durée de vie des WSN est très limitée, nous avons aussi proposé une nouvelle métrique de routage qui identifie les goulets d'étranglement énergétiques afin de maximiser la durée de vie du réseau. Enfin, en couplant cette mesure avec une version multiparent de RPL, nous avons résolu le problème d'instabilité souligné précédemment. / New protocols have been standardized in order to integrate Wireless Sensor Networks (WSN) in the Internet. Among them, the IEEE 802.15.4 MAC layer protocol, and RPL, the IPv6 Routing Protocol for Low-power and Lossy Networks. The goal of this thesis is to improve these protocols, considering the energy constraints of the devices that compose the WSN. First, we proposed a new MAC layer broadcast mechanism in IEEE 802.15.4, to ensure a reliable delivery of the control packets from the upper layers (especially from RPL). Then, we provided an exhaustive evaluation of RPL and highlighted an instability problem. This instability generates a large overhead, consuming a lot of energy. Since the lifetime of WSN is very limited, we proposed a new routing metric that identifies the energy bottlenecks and maximizes the lifetime of the network. Finally, by coupling this metric with a multipath version of RPL, we are able to solve the instability problem previously highlighted.
607

A Simplified Secure Programming Platform for Internet of Things Devices

Yesilyurt, Halim Burak 29 June 2018 (has links)
The emerging Internet of Things (IoT) revolution has introduced many useful applications that are utilized in our daily lives. Users can program these devices in order to develop their own IoT applications; however, the platforms and languages that are used during development are abounding, complicated, and time-consuming. The software solution provided in this thesis, PROVIZ+, is a secure sensor application development software suite that helps users create sophisticated and secure IoT applications with little software and hardware experience. Moreover, a simple and efficient domain-specific programming language, namely Panther language, was designed for IoT application development to unify existing programming languages. In addition to these contributions, PROVIZ+ supports a novel secure over-the-air programming framework, namely SOTA, using Bluetooth and WiFi as well as serial programming. In this thesis, we explain the features of PROVIZ+’s components, how these tools can help develop IoT applications, and SOTA. We also present the performance evaluations of PROVIZ+ and SOTA.
608

Proactive Adaptation of Behavior for Smart Connected Objects

Fejzo, Orsola January 2019 (has links)
The great amount of generated data from IoT infrastructures in Smart Cities, if properly leveraged, presents the opportunity to shift towards more sustainable practices in rapidly increasing urban areas. Reasoning upon this data in a proactive way, by avoiding unwanted future events before they occur, leads to more efficient services. For a system to do so, a robust reasoning model, able to anticipate upcoming events and pick the most suitable adaptation option is needed. Recently deployed smart waste management systems for monitoring and planning purposes report substantial cost-savings and carbon footprint reductions, however, such systems can be further enhanced by integrating proactive capabilities. This work proposes a novel reasoning model and system architecture called ProAdaWM for more effective and efficient waste operations when faced with severe weather events. A Bayesian Network and Utility Theory, as the basis of Decision Theory, are utilized to model the uncertainties and handle how the system adapts; the proposed model utilizes weather information and data from bin level sensor for reasoning. The approach is validated through the implementation of a prototype and the conduction of a case study; the results demonstrate the expected behavior.
609

Thriving in a Business Ecosystem : A study of role and capability alignment

Eriksson, Simon, Vidén, Ebba January 2018 (has links)
Purpose – The purpose of this study is to enhance the understanding of what capabilities that are required by actors in a business ecosystem depending on what role they enact. To fulfill this research purpose, the following research questions were derived: RQ1: What key activities underpin different ecosystem roles? and RQ2: What capabilities allow actors to perform key activities? Method – This study was conducted as an abductive single case-study of a business ecosystem that evolves around Internet-of-Things-based solutions in the automotive and transportation sector. In total, four companies and one expert company took part in the research, all participating in, or have knowledge of, the ecosystem of inquiry. In total, 20 interviews were conducted, and results were generated through the use of a thematic analysis. Findings – The findings from the study are summarized in a framework that illustrates what key activities actors perform to enact either an ‘Enabler’, ‘Leader’ or ‘Direct Value Creator’ role, and more specifically, what capabilities that allow actors to perform those key activities. The findings also show that actors must be able to leverage ‘ecosystem intelligence capabilities’, regardless of role, to be successful in a business ecosystem. Theoretical and practical implications – The study provide implications for research on business ecosystem by empirically explicating the key activities that underpin different ecosystem roles, and, by highlighting that actors must not only possess a set of role-specific capabilities, but also some generic capabilities that allow them to operate in a business ecosystem. Our framework assists managers to better evaluate if their firm can leverage the capabilities required to perform the activities of the role they aspire. Limitations and future research – The study is limited by a single case-study of a business ecosystem currently in the early phases. Hence, future research is recommended to validate and extend our findings in other contexts than of ours, as well as to study if the capabilityrequirements vary among different stages of ecosystem evolvement.
610

Placement des données de l'internet des objets dans une infrastructure de fog / Placement of internet of things data in a fog infrastructure

Naas, Mohammed Islam 19 February 2019 (has links)
Dans les prochaines années, l’Internet des objets (IoT) constituera l’une des applications générant le plus de données. Actuellement, les données de l’IoT sont stockées dans le Cloud. Avec l’augmentation du nombre d’objets connectés, la transmission de la grande quantité de données produite vers le Cloud génèrera des goulets d’étranglement. Par conséquent, les latences seront élevées. Afin de réduire ces latences, le Fog computing a été proposé comme un paradigme étendant les services du Cloud jusqu’aux périphéries du réseau. Il consiste à utiliser tout équipement localisé dans le réseau (ex. routeur) pour faire le stockage et le traitement des données. Cependant, le Fog présente une infrastructure hétérogène. En effet, ses équipements présentent des différences de performances de calcul, de capacités de stockage et d’interconnexions réseaux.Cette hétérogénéité peut davantage augmenter la latence du service. Cela pose un problème : le mauvais choix des emplacements de stockage des données peut augmenter la latence du service. Dans cette thèse, nous proposons une solution à ce problème sous la forme de quatre contributions : 1. Une formulation du problème de placement de données de l’IoT dans le Fog comme un programme linéaire. 2. Une solution exacte pour résoudre le problème de placement de données en utilisant CPLEX, un solveur de problème linéaire. 3. Deux heuristiques basées sur le principe de “diviser pour régner” afin de réduire le temps du calcul de placement. 4. Une plate-forme expérimentale pour évaluer des solutions de placement de données de l’IoT dans le Fog, en intégrant la gestion du placement de données à iFogSim, un simulateur d’environnement Fog et IoT. / In the coming years, Internet of Things (IoT) will be one of the applications generating the most data. Nowadays, IoT data is stored in the Cloud. As the number of connected objects increases, transmitting the large amount of produced data to the Cloud will create bottlenecks. As a result, latencies will be high and unpredictable. In order to reduce these latencies, Fog computing has been proposed as a paradigm extending Cloud services to the edge of the network. It consists of using any equipment located in the network (e.g. router) to store and process data. Therefore, the Fog presents a heterogeneous infrastructure. Indeed, its components have differences in computing performance, storage capacity and network interconnections. This heterogeneity can further increase the latency of the service. This raises a problem: the wrong choice of data storage locations can increase the latency of the service. In this thesis, we propose a solution to this problem in the form of four contributions: 1. A formulation of the IoT data placement problem in the Fog as a linear program. 2. An exact solution to solve the data placement problem using the CPLEX, a mixed linear problem solver. 3. Two heuristics based on the principle of “divide and conquer” to reduce the time of placement computation. 4. An experimental platform for testing and evaluating solutions for IoT data placement in the Fog, integrating data placement management with iFogSim, a Fog and IoT environment simulator.

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