Digitalisering genomsyrar fler och fler delar av dagens samhälle. Ett område där man nyligen börjat bedriva forskning är digitalt underhåll. Detta område är särskilt intressant när det gäller komponenter med lång livslängd som i exempelvis gruv- och transportindustrin då tiden för driftstopp av enheten kan minskas och rätt typ av underhåll kan ske genom rätt typ av diagnos. Detta leder till sänkta kostnader för företagen som implementerar digitalt underhåll. Fördelar med digitalt underhåll finns beskrivna i litteratur, men de viktiga faktorerna som behöver bearbetas för att kunna implementera det finns det i dagsläget inte mycket forskning kring. Syftet med denna studie var att utforma ett ramverk för vilka viktiga faktorer som bör tas i beaktning och dess samband då en organisation vill implementera digitalt underhåll, samt identifiera det resultat som uppstår då övergången till digitalt underhåll har genomförts. För att uppnå syftet genomfördes en abduktiv fallstudie kring digitalisering av järnvägsunderhåll på Sweco Rail AB, med fokus på deras största kund Trafikverket. En litteraturstudie genomfördes för att skapa en bild av problemet och data samlades in genom insamling av dokumenterat material och 26 intervjuer i tre faser; explorativa, semistrukturerade och uppföljande. Den data som samlades in analyserades sedan genom komparativ analys och tematisk kodning för att bidra till studiens resultat. Slutligen validerades resultatet med hjälp av experter inom området. Resultatet av studien var ett ramverk där fem faktorer som identifierats som viktiga att bearbeta för att implementera digitalt underhåll presenteras, deras samband samt det resultat som uppstår av att implementera det digitala underhållet visas. Ramverket innehåller faktorerna Digital teknik, Organisatorisk utveckling, Förändrade arbetssätt, Regelverk och Informationssäkerhet. I varje faktor identifierades även underkategorier. Ramverket visade även vad resultatet blir av att implementera digitalt underhåll.  Det praktiska bidraget är att ramverket hjälper organisationer att fokusera på de delarna som identifierats som viktiga. Detta för att implementeringen av digitalt underhåll ska bli så lyckad som möjligt, samtidigt som det visar de resultat som går att uppnå som en tydlig målbild. Det teoretiska bidraget är en fördjupad förståelse för området digitalt underhåll. Framtida forskning kan undersöka faktorerna hos företag som redan har genomfört en implementering av digitalt underhåll för att på så sätt verifiera resultaten från denna studie.

Le formaldéhyde est un polluant classé comme « hautement prioritaire » dans l’air intérieur. En raison de ses effets sur la santé, la réglementation française émergente (action 7 du PNSE2) impose de mesurer le formaldéhyde dans les lieux publics (écoles, crèches etc.) à partir de 2017. Or, aucun appareil sur le marché n’est capable de fournir des mesures précises, en temps réel et à faible coût. Cette thèse s’inscrit dans le cadre du projet ANR CAPFEIN (réseau de CAPteurs de FormaldEhyde intelligents pour la surveillance de l'air Intérieur) dont l’objectif est de réaliser un « capteur intelligent » de Formaldéhyde. Le sujet de thèse était de concevoir un système de surveillance en temps réel de l’exposition des personnes au Formaldéhyde, et plus généralement à n’importe quel polluant de l’air intérieur. Les capteurs doivent donc être dotés d’une interface de communication pour pouvoir collecter automatiquement les mesures en différents points de l’environnement à surveiller. Deux systèmes de surveillance ont été développés. Le premier repose sur des composants sur étagère et sur une architecture centralisée en se basant sur le concept de l'Internet des objets (IoT). Le second a été entièrement conçu au CRAN et correspond au développement d'une solution basée sur une approche distribuée. Un badge intelligent a été développé. Il permet de surveiller les taux d’exposition de chaque porteur de badge. Les contraintes majeures de ce travail ont été de pouvoir localiser les personnes dans un milieu intérieur, d’optimiser les algorithmes en termes de place mémoire et de consommation d’énergie. Pour la partie optimisation, des méthodes de moyenne mobile à pondération exponentielle ont été implémentées et évaluées. Les deux prototypes ont été testés dans les bâtiments du CRAN et ont montré leur intérêt. / Formaldehyde is classified as a "high priority" pollutant in the indoor air quality. Because of its health effects, the emerging French regulation (Action 7 of PNSE2) requires the measurement of formaldehyde in public places (schools, kindergartens etc.) from 2017. However, no device on the market is able to provide accurate measurements in real time and at low cost. This thesis forms part of the ANR project CAPFEIN (réseau de CAPteurs de FormaldEhyde intelligents pour la surveillance de l'air Intérieur) whose purpose is to develop a "smart Formaldehyde sensor". The thesis objective is to design a real-time monitoring system of human exposure to formaldehyde, and more generally to indoor air pollutant. The sensors must be equipped with a communication interface to automatically collect measurements at different points of the environment to be monitored. Two monitoring systems have been developed. The first is Designed with commercial off-the-shelf component and a centralized architecture based on the concept of the Internet of Things (IoT). The second was designed from the CRAN and corresponds to the development of a solution based on a distributed approach. A smart badge has been developed. It can monitor exposure levels to each cardholder. The major constraints of this work consist on the ability to locate people in an indoor environment and the ability to optimize the algorithms in terms of memory space and power consumption. For the optimization part, the moving average exponential weighting methods have been implemented and evaluated. Both prototypes were tested in buildings of CRAN and showed interest.

Les technologies Big Data gagnent de plus en plus d’attentions de communautés de recherches variées, surtout depuis que les données deviennent si volumineuses, qu’elles posent de réels problèmes, et que leurs traitements ne sont maintenant possibles que grâce aux grandes capacités de calculs des équipements actuels. De plus, les réseaux véhiculaires, aussi appelés VANET pour Vehicular Ad-hoc Networks, se développent considérablement et ils constituent une part de plus en plus importante du marché du véhicule. La topologie de ces réseaux en constante évolution est accompagnée par des données massives venant d’un volume croissant de véhicules connectés.Dans cette thèse, nous discutons dans notre première contribution des problèmes engendrés par la croissance rapide des VANET, et nous étudions l’adaptation des technologies liées aux Big Data pour les VANET. Ainsi, pour chaque étape clé du Big Data, nous posons le problème des VANET.Notre seconde contribution est l’extraction des caractéristiques liées aux VANET afin d’obtenir des données provenant de ceux-ci. Pour ce faire, nous discutons de comment établir des scénarios de tests, et comment émuler un environnement afin, dans un premier temps, de tester une implémentation dans un environnement contrôlé, avant de pouvoir effectuer des tests dans un environnement réel, afin d’obtenir de vraies données provenant des VANET.Pour notre troisième contribution, nous proposons une approche originale de la modélisation du comportement de conducteur. Cette approche est basée sur un algorithme permettant d’extraire des représentants d’une population, appelés exemplaires, en utilisant un concept de densité locale dans un voisinage. / Big Data is gaining lots of attentions from various research communities as massive data are becoming real issues and processing such data is now possible thanks to available high-computation capacity of today’s equipment. In the meanwhile, it is also the beginning of Vehicular Ad-hoc Networks (VANET) era. Connected vehicles are being manufactured and will become an important part of vehicle market. Topology in this type of network is in constant evolution accompanied by massive data coming from increasing volume of connected vehicles in the network.In this thesis, we handle this interesting topic by providing our first contribution on discussing different aspects of Big Data in VANET. Thus, for each key step of Big Data, we raise VANET issues.The second contribution is the extraction of VANET characteristics in order to collect data. To do that, we discuss how to establish tests scenarios, and to how emulate an environment for these tests. First we conduct an implementation in a controlled environment, before performing tests on real environment in order to obtain real VANET data.For the third contribution, we propose an original approach for driver's behavior modeling. This approach is based on an algorithm permitting extraction of representatives population, called samples, using a local density in a neighborhood concept.

This study focuses on the Internet of Things (IoT) gateway; a common middleware solution that bridges the gap between physical sensors and devices to internet applications. There is a shown interest in understanding the characteristics of different types of gateway architectures both from the research field and the industry, particularly the IT-consulting firm Attentec in Linköping, Sweden. A study has also been made on the open source C library libuv, used in the common web runtime engine NodeJS. The library has been used to study how asynchronous I/O operations can be used to improve the IoT gateway performance. A set of three general architectural approaches are identified. Common internal and external properties are identified based on state-of-the-art gateway implementations found in the industry. All of these properties are taken into account when a general gateway implementation is developed that is proposed to mimic any architectural level implementation of the gateway. A set of performance tests are conducted on the implementation to observe how different configurations of the gateway affect throughput and response time of data transmitted from simulated devices. The results show that the properties of the gateway do affect throughput and response time significantly and that libuv overall helps implement one of the best performing gateway configurations.

The Internet was initially built around networks based on physical cables, the next step to improve the accessibility of the Internet came with the introduction of wireless communication. the next step to improving accessibility to the Internet came with the introduction of wireless communication. Because the IoT products are wirelessly connected, they need an internal power source in the form of a battery. Many of the existing communication protocols are therefore not suitable for IoT solutions because they are power consuming. Alternatives to these communication protocols have therefore been developed, for example LTE-M, NB-IoT and LoRaWAN. The study was conducted in cooperation with Etteplan. Etteplan want to invest in LoRaWAN and thus want to gain deeper knowledge within LoRaWAN. Thus, it was chosen to investigate how different factors affect the signal strength transmission time in a LoRaWAN. The focus of the study has thus been on the communication between an IoT node and a receiver in a LoRaWAN, thus the purpose of the study: To show how different data rates, distances and environments affect the quality of information sent from an IoT node to a receiver in LoRaWAN. Design science research was used as a research method, in design science research an artefact is constructed and then studied. In this study, a LoRaWAN was constructed and the communication between an IoT node and receiver in this LoRaWAN was studied. To study the communication between the IoT node and the receiver, two experiments were performed. The experiments were performed simultaneously where the difference was in the data collected, one experiment collected the signal strength and the second the transmission time. The experiment was conducted in two different environments, one with a clear view and one with blockages. In the experiment, the IoT node was positioned at different distances with different data rates. The result of the study shows how different data rates, distances and environments affected the quality of information between an IoT node and receiver and how they relate to previous research. Data rate was the factor that affected the quality of the information most. Data rate had minimal impact on signal strength, but great impact on number of lost data packet and transmission times. The two different environments had no effect on the transmission time, but the signal strength was over 10 dbm lower in the urban environment than with clear view. The distance had no effect on transmission time and minimal impact on signal strength. / Internet var i begynnelsen uppbyggt kring nätverk baserade på fysiska kablar, nästa steg för att förbättra tillgängligheten till Internet kom med introduktionen av trådlös kommunikation. Ett nytt begrepp dök upp vid millennieskiftet, Internet of Things (IoT). Tanken bakom IoT är att olika typer av produkter, som exempelvis tandborstar och kylskåp trådlöst kopplas upp mot Internet. Eftersom IoT-produkterna är trådlöst uppkopplade behöver de en intern strömkälla i form av ett batteri. Många av de existerande kommunikationsprotokollen lämpar sig därför inte för IoT-lösningar eftersom dessa är strömkrävande. Alternativ till dessa kommunikationsprotokoll har därför tagits fram, till exempel LTE-M, NB-IoT och LoRaWAN. Studien utfördes i samarbete med Etteplan. Etteplan vill satsa på LoRaWAN och vill därmed få en djupare kunskap inom LoRaWAN. Därmed valdes det att undersöka hur olika faktorer påverkar signalstyrkan och sändningstiden i ett LoRaWAN. Studiens fokus har därmed varit på kommunikationen mellan en IoT-nod och en mottagare i ett LoRaWAN, därmed är studiens syfte: Att visa på hur olika datahastigheter, avstånd och miljöer påverkar kvaliteten på informationen som sänds från en IoT-nod till en mottagare i ett LoRaWAN. Design science research användes som forskningsmetod då i design science research konstrueras en artefakt som att sedan undersöks. I studiens fall konstruerades ett LoRaWAN där sedan kommunikationen mellan en IoT-nod och mottagare i detta LoRaWAN studerades. För att studera kommunikationen mellan en IoT-nod och en mottagare utfördes två experiment. Experimenten utfördes samtidigt där skillnaden låg i datat som samlades in, det ena experimentet samlade in signalstyrkan och den andra sändningstiden. Experimentet utfördes i två olika miljöer, en med fri sikt och en med blockeringar. I experimentet positionerades IoT-noden på olika avstånd med olika datahastigheter. Resultatet från studien visar hur olika datahastigheter, avstånd och miljöer påverkade kvaliteten på informationen mellan en IoT-nod och mottagare och hur de relateras till tidigare forskning. Datahastigheten var den faktorn som påverkade kvaliteten på informationen mest. Datahastigheten hade minimal påverkan på signalstyrkan, men stor påverkan på antal förlorade datapaket och sändningstider. De två olika miljöerna hade ingen påverkan på sändningstiden, men signalstyrkan var över 10 dbm lägre i stadsmiljön än med fri sikt. Avståndet hade ingen påverkan på sändningstiden och minimal påverkan på signalstyrkan.

abstract: With the new age Internet of Things (IoT) revolution, there is a need to connect a wide range of devices with varying throughput and performance requirements. In this thesis, a wireless system is proposed which is targeted towards very low power, delay insensitive IoT applications with low throughput requirements. The low cost receivers for such devices will have very low complexity, consume very less power and hence will run for several years. Long Term Evolution (LTE) is a standard developed and administered by 3rd Generation Partnership Project (3GPP) for high speed wireless communications for mobile devices. As a part of Release 13, another standard called narrowband IoT (NB-IoT) was introduced by 3GPP to serve the needs of IoT applications with low throughput requirements. Working along similar lines, this thesis proposes yet another LTE based solution called very narrowband IoT (VNB-IoT), which further reduces the complexity and power consumption of the user equipment (UE) while maintaining the base station (BS) architecture as defined in NB-IoT. In the downlink operation, the transmitter of the proposed system uses the NB-IoT resource block with each subcarrier modulated with data symbols intended for a different user. On the receiver side, each UE locks to a particular subcarrier frequency instead of the entire resource block and operates as a single carrier receiver. On the uplink, the system uses a single-tone transmission as specified in the NB-IoT standard. Performance of the proposed system is analyzed in an additive white Gaussian noise (AWGN) channel followed by an analysis of the inter carrier interference (ICI). Relationship between the overall filter bandwidth and ICI is established towards the end. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2017

abstract: The Internet of Things has conjured up a storm in the technology world by providing novel methods to connect, exchange, aggregate, and monitor data across a system of inter-related devices and entities. Of the myriad technologies that aid in the functioning of these IoT devices, Bluetooth Low Energy also known as BLE plays a major role in establishing inter-connectivity amongst these devices. This thesis aims to provide a background on BLE, the type of attacks that could occur in an IoT setting, the possible defenses that are available to prevent the occurrence of such attacks, and a discussion on the research trends that hold great promise in presenting seamless solutions to integrate IoT devices across different industry verticals. / Dissertation/Thesis / Masters Thesis Computer Science 2017

The client in this study, Attentec, has seen an increase in the demand for services connected to Internet of things systems. This study is therefore examining if there is a tool that can be a used to build fast prototype visualisations of data from IoT systems to use as a tool in their daily work. The study started with an initial phase with two parts. The first part was to get better knowledge of Attentec and derive requirements for the tool and the second part was a comparison of prototyping tools for aiding in development of data visualisations. Apache Zeppelin was chosen as the most versatile and suitable tool matching the criteria defined together with Attentec. Following the initial phase a pre-study containing interviews to collect empirical data on how visualisations and IoT projects had been implemented previously at Attentec were performed. This lead to the conclusion that geospatial data and NoSQL databases were common for IoT projects. A technical investigation was conducted on Apache Zeppelin to answer if there were any limits in using the tool for characteristics common in IoT system. This investigation lead to the conclusion that there was no support for plotting data on a map. The first implementation phase implemented support for geospatial data by adding a visualisation plug-in that plotted data on a map. The implementation phase was followed by an evaluation phase in which 5 participants performed tasks with Apache Zeppelin to evaluate the perceived usability of the tool. The evaluation was performed using a System Usability Scale and a Summed Usability Metric as well as interviews with the participants to find where improvements could be made. From the evaluation three main problems were discovered, the import and mapping of data, more feature on the map visualisation plug-in and the creation of database queries. The first two were chosen for the second iteration where a script for generating the code to import data was developed as well as improvements to the geospatial visualisation plug-in. A second evaluation was performed after the changes were made using similar tasks as in the first to see if the usability was improved between the two evaluations. The results of the Summed Usability Metric improved on all tasks and the System Usability Scale showed no significant change. In the interviews with the participants they all responded that the perceived usability had improved between the two evaluations suggesting some improvement.

The Internet of Things (IoT) comprises a large number of heterogeneous devices. It is forecasted that up to 50 billion devices will be connected to the Internet by 2020. All of them have to be configured. Due to the heterogeneity of devices and the enormous increasing number of devices, manual configuration becomes more and more complex and inefficient. Zero configuration is put forward to solve this problem, which makes device configured automatically without additional manual involvement. Besides that, there are many security threats we want to avoid in the future. These security problems include unauthenticated nodes accessing to IoT data, denial of service, lack of confidentiality, malicious attack from hackers and so on. This paper studies the characteristics of IoT firstly and then highlights the implementation of zero configuration and security to IoT. This paper describes the underlying features of zero configuration and primary requirements of security, as well as finds some related mature technologies, based on that proposes a concise solution – combining the Bonjour and many security approaches for implementation of a secure zero IoT system. In addition, this solution is implemented in a small environment scenario of IoT, a smart home. All the programs are in Java language. Evaluation and conclusion are done in final phase.

Nos travaux s’orientent vers les problèmes de réseaux sans fil liés à la coexistence des communications machine-to-machine (M2M) et humain-humain (H2H). On souhaite souligner l'impact mutuel entre les trafics M2M et H2H dans un contexte d’Internet des objets (IoT : Internet Of Things) en particulier lors des catastrophes. Les communications M2M, qui devraient connaître une roissance exponentielle dans un avenir proche, constitueront un facteur important pour affecter tous les réseaux mobiles. On prévoit un grand nombre d'appareils M2M qui entraînera inévitablement des problèmes de saturation et aura des impacts remarquables sur les trafics, les services et les applications M2M et H2H. Pour étudier les influences mutuelles M2M et H2H, nous développons un nouveau modèle markovien à temps continu (CTMC) pour simuler, analyser et mesurer les différentes stratégies d'accès aux réseaux sans fil. Notre modèle nous a permis de contourner certaines limitations des simulateurs professionnels de LTE-A (Long Term Evolution-Advanced) comme SimuLTE en terme d’un nombre massif d'appareils M2M, une flexibilité de certains paramètres ou pour élaborer plus des outils statistiques. Lors d’un sinistre et suite à un énorme nombre de M2M souhaitant accéder aux réseaux sans-fil, nous avons constaté un épuisement rapide de la bande passante allouée dans les réseaux LTE-M (Long Term Evolution for Machines) ou Narrow Band for IoT (NB-IoT). Pour résoudre ce problème, nous proposons une nouvelle approche appelée Adaptive eNodeB (A-eNB) pour les réseaux LTE-M et NB-IoT. Selon nos simulations, l’A-eNB peut résoudre progressivement le problème de surcharge tout en assurant une satisfaisante qualité de service (QoS) pour le trafic H2H. Avec le concept d’A-eNB, un réseau LTE-M pourra adapter ses ressources pour faire face à une augmentation progressive du nombre de connexions M2M accédant au réseau LTE-M / NB-IoT et en même temps réduire l'impact sur le trafic H2H. / This Ph.D. work aims to study the Machine-to-Machine (M2M) congestion overload problem and the mutual impact among M2M and Human-to-Human (H2H) traffics in IoT (Internet of Things) environments specifically during disaster events. M2M devices with their expected exponential booming in the near future, will be one of the significant factors to influence all mobile networks. Inevitably, the expected huge number of M2M devices causes saturation problems, and leads to remarkable impacts on both M2M and H2H traffics, services and applications. To study the M2M and H2H mutual influences, we create a new platform model based on Continuous-Time Markov Chain (CTMC) to simulate, analyze and measure radio access strategies due to the limitations of existing Long Term Evolution-Advanced (LTE-A) simulators (i.e, SimuLTE) in term of massive M2M devices, parameter flexibility and statistical tools. Additionally, during disaster events, a fast bandwidth depletion of the limited bandwidth assigned to M2M devices in Long Term Evolution for Machines (LTE-M) and Narrow Band for IoT (NB-IoT) networks is expected due to the high arrival request of M2M device network access. To address this problem, we propose a new approach named Adaptive eNodeB (A-eNB) for both LTE-M and NB-IoT networks. The A-eNB can solve gradually the overload problem, while keeping the H2H traffic Quality of Service (QoS) not to be affected badly. The network adaptation is provided through a dynamic LTE-M resource reservation aiming to increase the number of M2M connections accessing the LTE-M/NB-IoT network and to decrease the impact on H2H traffic.