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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.
11

Analyse environnementale et éco-conception de services informationnels

Bonvoisin, Jérémy 05 November 2012 (has links) (PDF)
L'essor des services et des technologies de l'information et de la communication (TIC) est généralement considéré comme le marqueur d'une dématérialisation de l'économie - phénomène grandement attendu dans le cadre des discussions sur le développement durable. Nous nous plaçons dans le débat autour de cette hypothèse en questionnant la matérialité des TIC et des services à travers le cas des services informationnels - activités de génération d'information répondant à un besoin décisionnel. Nous examinons plus en détail les services d'optimisation basés sur les réseaux de capteurs - services offerts à l'aide d'informations collectées par des capteurs intégrés dans un réseau sans fil, permettant de surveiller un processus dans le but de l'optimiser, et par là-même de diminuer ses impacts. Nous proposons ainsi une méthode intégrée d'analyse environnementale et d'éco-conception des services d'optimisation basés sur les réseaux de capteurs. Celle-ci permet de déterminer la pertinence environnementale d'un service, c'est-à-dire sa capacité à générer moins d'impacts qu'il n'en évite, mais également de le concevoir avec cette pertinence en vue. Notre apport scientifique réside dans la proposition d'un modèle d'impact pour les services informationnels et d'un modèle de cycle de vie des réseaux de capteurs, ainsi que dans le développement d'un outil d'analyse basé sur la simulation réseau. L'application de la méthode proposée au cas d'un service d'optimisation de la collecte de déchets nous permet de conclure que, si des marges de manœuvres importantes sont identifiables, la pertinence environnementale de ces services ne doit pas être considérée comme acquise, tout comme le potentiel de dématérialisation des TIC et des services.
12

Synthesis and evaluation of a data management system for machine-to-machine communication

Jordaan, Pieter Willem January 2013 (has links)
A use case for a data management system for machine-to-machine communication was defined. A centralized system for managing data flow and storage is required for machines to securely communicate with other machines. Embedded devices are typical endpoints that must be serviced by this system and the system must, therefore, be easy to use. These systems have to bill the data usage of the machines that make use of its services. Data management systems are subject to variable load and must there- fore be able to scale dynamically on demand in order to service end- points. For robustness of such an online-service it must be highly available. By following design science research as the research methodology, cloud-based computing was investigated as a target deployment for such a data management system in this research project. An implementation of a cloud-based system was synthesised, evaluated and tested, and shown to be valid for this use case. Empirical testing and a practical field test validated the proposal. / Thesis (MIng (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013.
13

Synthesis and evaluation of a data management system for machine-to-machine communication

Jordaan, Pieter Willem January 2013 (has links)
A use case for a data management system for machine-to-machine communication was defined. A centralized system for managing data flow and storage is required for machines to securely communicate with other machines. Embedded devices are typical endpoints that must be serviced by this system and the system must, therefore, be easy to use. These systems have to bill the data usage of the machines that make use of its services. Data management systems are subject to variable load and must there- fore be able to scale dynamically on demand in order to service end- points. For robustness of such an online-service it must be highly available. By following design science research as the research methodology, cloud-based computing was investigated as a target deployment for such a data management system in this research project. An implementation of a cloud-based system was synthesised, evaluated and tested, and shown to be valid for this use case. Empirical testing and a practical field test validated the proposal. / Thesis (MIng (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013.
14

Protocol design for machine-to-machine networks

Aijaz, Adnan January 2014 (has links)
Machine-to-Machine (M2M) communications is an emerging communication paradigm that provides ubiquitous connectivity between devices along with an ability to communicate autonomously without human intervention. M2M communications acts as an enabling technology for the practical realization of Internet-of-Things (IoT). However, M2M communications differs from conventional Human-to-Human (H2H) communications due to its unique features such as massive number of connected devices, small data transmissions, little or no mobility, requirements of high energy efficiency and reliability, etc. These features create various challenges for existing communication networks which are primarily optimized for H2H communications. Therefore, novel solutions are required to meet the key requirements of M2M communications. In addition, enhancements are required at different layers of the protocol stack to support co-existence of M2M devices and H2H users. The main objective of this research is to investigate the challenges of M2M communications in two broad types of M2M networks; capillary M2M and cellular M2M networks. The primary focus is on developing novel solutions, algorithms, and protocol enhancements for successfully enabling M2M communications. Since cognitive radio technology is very promising for M2M communications, special emphasis is on capillary M2M networks with cognitive radio based Physical layer. Besides, the focus is also on exploring new frontiers in M2M communications. This thesis covers different aspects of M2M communications. Considering the motivation for cognitive M2M and service requirements of M2M devices, two cognitive MAC protocols have been proposed. The first protocol is centralized in nature and utilizes a specialized frame structure for co-existence with the primary network as well as handling different Quality-of-Service (QoS) requirements of M2M devices. The second protocol is a distributed cognitive MAC protocol, which is specially designed to provide high energy efficiency and reliability for M2M devices operating in challenging wireless environments. Both protocols explicitly account for the peculiarities of cognitive radio environments. The protocols have been evaluated using analytical modeling and simulation studies. Recently IETF has standardized a specially designed routing protocol for capillary M2M networks, known as RPL (Routing for Low Power and Lossy Networks). RPL is emerging as the de facto routing protocol for many M2M applications including the smart grid. On the other hand, the application of cognitive radio for smart grid communication is under active investigation in the research community. Hence, it is important to investigate the applicability and adaptation of RPL in cognitive radio environments. In this regard, an enhanced RPL based routing protocol has been proposed for cognitive radio enabled smart grid networks. The enhanced protocol provides novel modifications to RPL for protecting the primary users along with meeting the utility requirements of the secondary network. An important challenge in LTE-based cellular networks with M2M communications is the uplink radio resource management as available resources are shared between M2M devices and H2H users, having different and often conflicting QoS requirements. Apart from this, energy efficiency requirements become critically important. Further, the specific constraints of Single Carrier Frequency Division Multiple Access (SC-FDMA) complicate the resource allocation problem. In this respect, an energy efficient resource allocation algorithm for the uplink of LTE networks with M2M/H2H co-existence under statistical QoS guarantees has been developed, that is based on canonical duality theory. The proposed algorithm outperforms classical algorithms in terms of energy efficiency while satisfying the QoS requirements of M2M devices and H2H users. A new frontier in M2M communications is the nano-M2M communications, which is envisioned to create the Internet-of-Nano-Things (IoNT). Molecular communication (MC) is a promising communication technique for nano-M2M communications. In literature, no model for error performance of MC exists. Therefore, an error performance model has been developed that explicitly accounts for noise and interference effects. Since relaying and network coding based solutions are gaining popularity for nano-M2M networks, the error performance of a network coded molecular nano-M2M network has been evaluated as well. Finally, the thesis is concluded based on the overall picture of the research conducted. In addition, some directions for future work are included as well.
15

Design and Application of Wireless Machine-to-Machine (M2M) Networks

Zheng, Lei 24 December 2014 (has links)
In the past decades, wireless Machine-to-Machine (M2M) networks have been developed in various industrial and public service areas and envisioned to improve our daily life in next decades, e.g., energy, manufacturing, transportation, healthcare, and safety. With the advantage of low cost, flexible deployment, and wide coverage as compared to wired communications, wireless communications play an essential role in providing information exchange among the distributed devices in wireless M2M networks. However, an intrinsic problem with wireless communications is that the limited radio spectrum resources may result in unsatisfactory performance in the M2M networks. With the number of M2M devices projected to reach 20 to 50 billion by 2020, there is a critical need to solve the problems related to the design and applications in the wireless M2M networks. In this dissertation work, we study the wireless M2M networks design from three closely related aspects, the wireless M2M communication reliability, efficiency, and Demand Response (DR) control in smart grid, an important M2M application taking the advantage of reliable and efficient wireless communications. First, for the communication reliability issue, multiple factors that affect communication reliability are considered, including the shadowing and fading characteristics of wireless channels, and random network topology. A general framework has been proposed to evaluate the reliability for data exchange in both infrastructure-based single-hop networks and multi-hop mesh networks. Second, for the communication efficiency issue, we study two challenging scenarios in wireless M2M networks: one is a network with a large number of end devices, and the other is a network with long, heterogeneous, and/or varying propagation delays. Media Access Control (MAC) protocols are designed and performance analysis are conducted for both scenarios by considering their unique features. Finally, we study the DR control in smart grid. Using Lyapunov optimization as a tool, we design a novel demand response control strategy considering consumer’s comfort requirements and fluctuations in both the renewable energy supply and customers’ load demands. By considering those unique features of M2M networks in data collection and distribution, the analysis, design and optimize techniques proposed in this dissertation can enable the deployment of wireless M2M networks with a large number of end devices and be essential for future proliferation of wireless M2M networks. / Graduate / 0544 / flintlei@gmail.com
16

Internet das coisas aplicada à indústria: dispositivo para interoperabilidade de redes industriais

Keller, Armando Leopoldo 13 January 2017 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2017-04-20T13:56:57Z No. of bitstreams: 1 Armando Leopoldo Keller_.pdf: 2124143 bytes, checksum: ba23113da63873463958e38c05ddbd88 (MD5) / Made available in DSpace on 2017-04-20T13:56:57Z (GMT). No. of bitstreams: 1 Armando Leopoldo Keller_.pdf: 2124143 bytes, checksum: ba23113da63873463958e38c05ddbd88 (MD5) Previous issue date: 2017-01-13 / Nenhuma / O objetivo deste trabalho, é realizar um estudo de forma mais abrangente sobre o conceito de Internet das Coisas e seus principais protocolos. Explora-se especificamente o conceito de IoT (Internet of Things) aplicado em sistemas de automação. Para tanto é apresentada uma revisão bibliográfica sobre o assunto, explorando os diversos protocolos desenvolvidos para aplicações de IoT, caracterizando-os quanto a taxa de transmissão, eficiência, segurança e confiabilidade. Também é realizado um levantamento do cenário atual, quanto a aplicação de protocolos de IoT em sistemas de automação, sempre tendo em mente a confiabilidade do sistema. Percebe-se que um grande dificultador do uso destes tipos de protocolo em ambientes industriais é justamente a heterogeneidade das redes existentes. Diante deste problema, a proposta do trabalho é desenvolver um dispositivo que atue como middleware para a interligação de redes de automação distribuídas, no caso especificamente a rede Modbus RTU, fazendo com que esta interligação seja de forma transparente utilizando o protocolo de Internet das Coisas MQTT (Message Queuing Telemetry Transport). Este dispositivo é testado com equipamentos em um cenário real através de um estudo de caso, onde duas redes Modbus RTU de um sistema geograficamente distribuído de geração de energia solar fotovoltaica, são interligadas, permitindo a criação de uma planta virtual de geração de energia do inglês virtual power plant (VPP). Com isso é possível tratar e gerenciar os sistemas distribuídos de geração como sendo uma única unidade geradora, facilitando o despacho. Para comprovar a eficiência e a confiabilidade do sistema, foram realizados testes onde o tempo entre as requisições e respostas foi medido, e através da sua distribuição foi obtido um tempo de 2,5 segundos para obter uma comunicação com baixa taxa de perda de mensagens. Estes testes comprovam o correto funcionamento do sistema proposto. / The objective of this work is to develop a more comprehensive study on the concept of Internet of Things (IoT) and its main protocols, specifically exploring the concept of IoT applied in automation systems. A bibliographic review explores the diverse protocols developed for IoT applications, characterizing them as transmission rate, efficiency, safety and confiability. A survey of the current scenario about the application of IoT protocols in automation systems is presented, always having the system confiability in mind. The heterogenity of the existent networks makes the use of this protocols a harder task. The proposal of this work is develop a device that acts as middleware for interlink distributed automation networks, in this case the Modbus RTU networks, in a transparent way using the internet of things procol MQTT (Message Queuing Telemetry Transport). This device is tested with equipments in a real scenario trough a case study, where two Modbus RTU networks of a geographically distributed solar photovoltaic power plant, is interlinked, allowing the criation of a VPP (Virtual Power Plant). This makes possible to manage the distributed power generator systems as a single generator unit, improving the electric energy dispatch. To prove the efficiency and confiability of the system, tests were made where the time between request and response was mensured, and based on his distribution the time of 2.5 seconds was determined to have a low message loss communication. Those tests validate the proposed system and the achievement of the goals of the present work.
17

Technique distribuée de gestion de la charge sur le réseau électrique et Ring-Tree : un nouveau système de communication P2P

Ayoub, Simon January 2013 (has links)
Le réseau de distribution et de transport de l’électricité se modernise dans plusieurs pays dont le Canada. La nouvelle génération de ce réseau que l’on appelle smart grid, permet entre autre l’automatisation de la production, de la distribution et de la gestion de la charge chez les clients. D’un autre côté, des appareils domestiques intelligents munis d’une interface de communication pour des applications du smart grid commencent à apparaître sur le marché. Ces appareils intelligents pourraient créer une communauté virtuelle pour optimiser leurs consommations d’une façon distribuée. La gestion distribuée de ces charges intelligentes nécessite la communication entre un grand nombre d’équipements électriques. Ceci représente un défi important à relever surtout si on ne veut pas augmenter le coût de l’infrastructure et de la maintenance. Lors de cette thèse deux systèmes distincts ont été conçus : un système de communication peer-to-peer, appelé Ring-Tree, permettant la communication entre un nombre important de nœuds (jusqu’à de l’ordre de grandeur du million) tel que des appareils électriques communicants et une technique distribuée de gestion de la charge sur le réseau électrique. Le système de communication Ring-Tree inclut une nouvelle topologie réseau qui n’a jamais été définie ou exploitée auparavant. Il inclut également des algorithmes pour la création, l’exploitation et la maintenance de ce réseau. Il est suffisamment simple pour être mis en œuvre sur des contrôleurs associés aux dispositifs tels que des chauffe-eaux, chauffage à accumulation, bornes de recharges électriques, etc. Il n’utilise pas un serveur centralisé (ou très peu, seulement lorsqu’un nœud veut rejoindre le réseau). Il offr une solution distribuée qui peut être mise en œuvre sans déploiement d’une infrastructure autre que les contrôleurs sur les dispositifs visés. Finalement, un temps de réponse de quelques secondes pour atteindre l’ensemble du réseau peut être obtenu, ce qui est suffisant pour les besoins des applications visées. Les protocoles de communication s’appuient sur un protocole de transport qui peut être un de ceux utilisés sur l’Internet comme TCP ou UDP. Pour valider le fonctionnement de de la technique de contrôle distribuée et le système de communication Ring-Tree, un simulateur a été développé; un modèle de chauffe-eau, comme exemple de charge, a été intégré au simulateur. La simulation d’une communauté de chauffe-eaux intelligents a montré que la technique de gestion de la charge combinée avec du stockage d’énergie sous forme thermique permet d’obtenir, sans affecter le confort de l’utilisateur, des profils de consommation variés dont un profil de consommation uniforme qui représente un facteur de charge de 100%.
18

A distributed service delivery platform for automotive environments : enhancing communication capabilities of an M2M service platform for automotive application

Glaab, Markus January 2018 (has links)
The automotive domain is changing. On the way to more convenient, safe, and efficient vehicles, the role of electronic controllers and particularly software has increased significantly for many years, and vehicles have become software-intensive systems. Furthermore, vehicles are connected to the Internet to enable Advanced Driver Assistance Systems and enhanced In-Vehicle Infotainment functionalities. This widens the automotive software and system landscape beyond the physical vehicle boundaries to presently include as well external backend servers in the cloud. Moreover, the connectivity facilitates new kinds of distributed functionalities, making the vehicle a part of an Intelligent Transportation System (ITS) and thus an important example for a future Internet of Things (IoT). Manufacturers, however, are confronted with the challenging task of integrating these ever-increasing range of functionalities with heterogeneous or even contradictory requirements into a homogenous overall system. This requires new software platforms and architectural approaches. In this regard, the connectivity to fixed side backend systems not only introduces additional challenges, but also enables new approaches for addressing them. The vehicle-to-backend approaches currently emerging are dominated by proprietary solutions, which is in clear contradiction to the requirements of ITS scenarios which call for interoperability within the broad scope of vehicles and manufacturers. Therefore, this research aims at the development and propagation of a new concept of a universal distributed Automotive Service Delivery Platform (ASDP), as enabler for future automotive functionalities, not limited to ITS applications. Since Machine-to-Machine communication (M2M) is considered as a primary building block for the IoT, emergent standards such as the oneM2M service platform are selected as the initial architectural hypothesis for the realisation of an ASDP. Accordingly, this project describes a oneM2M-based ASDP as a reference configuration of the oneM2M service platform for automotive environments. In the research, the general applicability of the oneM2M service platform for the proposed ASDP is shown. However, the research also identifies shortcomings of the current oneM2M platform with respect to the capabilities needed for efficient communication and data exchange policies. It is pointed out that, for example, distributed traffic efficiency or vehicle maintenance functionalities are not efficiently treated by the standard. This may also have negative privacy impacts. Following this analysis, this research proposes novel enhancements to the oneM2M service platform, such as application-data-dependent criteria for data exchange and policy aggregation. The feasibility and advancements of the newly proposed approach are evaluated by means of proof-of-concept implementation and experiments with selected automotive scenarios. The results show the benefits of the proposed enhancements for a oneM2M-based ASDP, without neglecting to indicate their advantages for other domains of the oneM2M landscape where they could be applied as well.
19

Personal machine-to-machine (M2M) healthcare system with mobile device in global networks

Jung, S.-J. (Sang-Joong) 02 December 2013 (has links)
Abstract This thesis describes the development of a personal machine-to-machine (M2M) healthcare system that is both flexible and scalable. Based on the IPv6 protocol, the system can be used over a low-power wireless personal area network (6LoWPAN). Since a hierarchical network structure offers excellent accessibility, the system is applicable both to local and international healthcare services. To further enhance scalability and reliability, the proposed system combines 6LoWPAN with mobile techniques, depending on whether the sensor is located inside or outside the range of a wireless sensor network (WSN). Employing wearable low-power sensors, the system measures health parameters dynamically. For wireless transmission, these sensors are connected to an M2M node either through the internet or through an external IPv4/IPv6-enabled network. The applicability of the IEEE 802.15.4 and 6LoWPAN protocols to wide area networks were verified in practical tests using an M2M gateway. To assess the physical health of an individual, the system uses heart rate variability analysis in time and frequency domains. Acquired data are first stored on a server for analysis. Results of the analysis are then automatically sent to Android-based mobile devices carried by the individual or appointed healthcare providers. In this way, mobile techniques are used to support remote health monitoring services. This personal M2M healthcare system has the capacity to accurately process a large amount of biomedical signals. Moreover, due to its ability to use mobile technology, the system allows patients to conveniently monitor their own health status, regardless of location. / Tiivistelmä Tutkimuksessa kehitetään henkilökohtainen mobiililaitteden välillä toimiva (M2M) terveydenhoitojärjestelmä, joka mahdollistaa joustavan ja skaalautuvan potilaan terveyden monitoroinnin. Perustuen IPv6-protokollaan, sovellusta voidaan käyttää matalatehoisen langattoman 6LowPAN-verkon yli. Koska hierarkkinen verkkorakenne tarjoaa erinomaisen saavutettavuuden, järjestelmän kapasiteetti riittää paitsi kaupungin sisäisten myös kansainvälisten terveyspalvelujen järjestämiseen. Skaalattavuuden ja luotettavuuden vuoksi ehdotettu järjestelmä yhdistelee 6LowPAN-tekniikkaa mobiiliteknologiaan riippuen siitä onko sensori langattoman sensoriverkon kuuluvuusalueella vai sen ulkopuolella. Puettavia matalatehoisia sensoreita käyttävä järjestelmä kykenee mittaamaan terveysparametreja dynaamisesti. Langatonta siirtoa varten nämä sensorit on kytketty M2M-solmuun joko internetin tai ulkoisen IPv4/IPv6-verkon kautta. Käytännön testeissä IEEE802.15.4- ja 6LowPAN-protokollien soveltaminen laajaverkossa mahdollistettiin tähän soveltuvalla M2M-yhdyskäytävällä. Yksilöiden fyysisen terveyden arvioinnissa järjestelmä käyttää sydämen sykevaihtelun analysointia aika- ja taajuustasossa. Data tallennetaan palvelimelle analysointia varten. Analyysin tulokset lähetetään automaattisesti henkilöiden omiin tai heidän lääkäriensä mobiililaitteisiin. Näin mobiiliteknologiaa käytetään tukemaan terveyden etämonitorointipalveluja. Tämä henkilökohtainen M2M-kommunikointiin perustuva terveydenhoitojärjestelmä kykenee käsittelemään tarkkaan suuriakin määriä 6LowPAN-verkon ja internetin kautta tulevia biolääketieteellisiä signaaleja. Lisäksi kyky käyttää mobiiliteknologiaa tekee järjestelmästä potilaille miellyttävän tavan monitoroida omaa terveydentilaansa sijaintipaikasta riippumatta.
20

Automatic Log Analysis System Integration : Message Bus Integration in a Machine Learning Environment

Svensson, Carl January 2015 (has links)
Ericsson is one of the world's largest providers of communications technology and services. Reliable networks are important to deliver services that live up to customers' expectations. Tests are frequently run on Ericsson's systems in order to identify stability problems in their networks. These tests are not always completely reliable. The logs produced by these tests are gathered and analyzed to identify abnormal system behavior, especially abnormal behavior that the tests might not have caught. To automate this analysis process, a machine learning system, called the Awesome Automatic Log Analysis Application (AALAA), is used at Ericsson's Continuous Integration Infrastructure (CII)-department to identify problems within the large logs produced by automated Radio Base Station test loops and processes. AALAA is currently operable in two versions using different distributed cluster computing platforms: Apache Spark and Apache Hadoop. However, it needs improvements in its machine-to-machine communication to make this process more convenient to use. In this thesis, message communication has successfully been implemented in the AALAA system. The result is a message bus deployed in RabbitMQ that is able to successfully initiate model training and abnormal log identification through requests, and to handle a continuous flow of result updates from AALAA. / Ericsson är en av världens största leverantörer av kommunikationsteknologi och tjänster. Tillförlitliga nätverk är viktigt att tillhandahålla för att kunna leverera tjänster som lever upp till kundernas förväntningar. Tester körs därför ofta i Ericssons system med syfte att identifiera stabilitetsproblem som kan uppstå i nätverken. Dessa tester är inte alltid helt tillförlitliga, producerade testloggar samlas därför in och analyseras för att kunna identifiera onormalt beteende som testerna inte lyckats hitta. För att automatisera denna analysprocess har ett maskininlärningssystem utvecklats, Awesome Automatic Log Analysis Application (AALAA). Detta system används i Ericssons Continuous Integration Infrastructure (CII)-avdelning för att identifiera problem i stora loggar som producerats av automatiserade Radio Base Station tester. AALAA är för närvarande funktionellt i två olika versioner av distribuerad klusterberäkning, Apache Spark och Apache Hadoop, men behöver förbättringar i sin maskin-till-maskin-kommunikation för att göra dem enklare och effektivare att använda. I denna avhandling har meddelandekommunikation implementerats som kan kommunicera med flera olika moduler i AALAA. Resultatet är en meddelandebuss implementerad i RabbitMQ som kan initiera träning av modeller och identifiering av onormala loggar på begäran, samt hantera ett kontinuerligt flöde av resultatuppdateringar från pågående beräkningar.

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