Product Lifecycle Management (PLM) is a holistic approach for managing product information throughout its life cycle. It integrates different concepts that have emerged due to changes in the manufacturing process as a result of globalization, increased competition, demand for more innovative products, and other reasons. These changes have leaded to a shift from a model with a single-location for product development to a model in which a complex network of specialized companies collaborate. This global collaborative PLM implies that companies from different parts of the world work together and must share information; hence the underlying PLM system is required to facilitate data management throughout this collaborative process. In addition, it is also necessary to address the challenges due to the new model being a distributed activity, as today this PLM system is a specialized distributed system. Maintaining data consistency can be challenging because collaborators can use heterogeneous PLM systems together with their own databases. The later cannot be shared due to the risks of exposing their knowledge base and business processes. Another consideration in global collaboration is that data is transmitted to remote locations. As a result network latency can be large; this can cause problems particularly when large files are exchanged, such as may be the case for CAD design models. This thesis proposes a solution enabling a global PLM which addresses the challenges described above. The approach consists of connecting collaborators’ nodes in a network that is constructed by grouping them with respect to intra-site latency. Each group implements a coordination mechanism based on the election of a node which is subsequently in charge of coordinating data access. The groups communicate via a publish-subscribe communication pattern, publishing and subscribing to events related to the resources being shared. The integration of the solution is through a Service-oriented Architecture (SOA) implementing web services that can be consumed by a PLM system. A prototype has been implemented and its applicability is analysed by evaluating its functionality in a collaborative scenario based on the Aras Innovator PLM platform. The evaluation was made by simulating the solution proposed and comparing it with a centralized approach. The results particularly showed that the proposed solution could reduce the intra-latency compared to a centralized approach if the collaborators are organized in collaborative groups, that exchange most of the information inside the group rather than intergroup. / Product Lifecycle Management (PLM) är en helhetssyn som hanterar produktinformation under deras hela livscykel. PLM integrerar olika koncept som har dykt upp på grund av förändringar i tillverkningsprocessen som en följd av globalisering, stor konkurrens, efterfrågan på mer innovativa produkter, och andra orsaker. Dessa förändringar har blyad till en övergång från en modell med en enda plats för produktutveckling till en modell där ett komplext nätverk av specialiserade företag samarbetar. Detta globala samarbete inom PLM innebär att företag från olika delar av världen arbetar tillsammans och delar information. Det underliggande PLM-systemet krävs att underlätta datahantering hela denna samverkande process. Dessutom är det också nödvändigt att hantera utmaningar beroende på den nya distribuerade modellen som gör PLM -system blir specialiserade distribuerade system. Underhålla uppgifter konsekvens kan vara en utmaning eftersom kollaboratörer kan använda heterogena PLM-system med sina egna databaser som inte kan delas på grund av riskerna för att utsätta sin kunskapsbas och affärsprocesser . En annan faktor i den globala samarbetet är att data överförs till avlägsna platser . Som ett resultat nätverksfördröjningen kan vara stora, vilket kan orsaka problem speciellt när stora filer utbyts, exempelvis CAD-modeller. Detta masterarbete föreslår en lösning för att möjliggöra en global PLM som tar upp de utmaningar som beskrivs ovan. Tillvägagångssättet består av anslutande kollaboratörer noder i ett nätverk som konstrueras genom att gruppera dem i förhållande till intra-site latens. Varje grupp genomför en mekanism för samordning grundas på valet av en nod som därefter ansvarar för samordningen av dataåtkomst. Grupperna kommunicerar via en publiceraprenumerera kommunikationen mönster av att publicera och prenumerera på händelser relaterade till de resurser som delas. Integrationen av lösningen är genom en Service-Oriented Architecture (SOA) genomföra webbtjänster som kan konsumeras av ett PLM-system. En prototyp har genomförts och dess användbarhet analyseras genom att utvärdera dess funktionalitet i en kollaborativ scenario baserat på Aras Innovator PLM-plattform. Resultaten visade att den föreslagna lösningen skulle kunna minska intra-latens jämfört med en centraliserad strategi om kollaboratörer är organiserade i kollaborativa grupper, varje grupp är ansvarig för utformningen ett delsystem av produkten och därmed utbyta mesta av informationen inom gruppen snarare än inter-gruppen.

Wireless sensor networks (WSNs) is a virtual layer in the paradigm of the Internet of Things (IoT). It inter-relates information associated with the physical domain to the IoT drove computational systems. WSN provides an ubiquitous access to location, the status of different entities of the environment, and data acquisition for long-term IoT monitoring. Since energy is a major constraint in the design process of a WSN, recent advances have led to project various energy-efficient protocols. Routing of data involves energy expenditure in considerable amount. In recent times, various heuristic clustering protocols have been discussed to solve the purpose. This article is an improvement of the existing stable election protocol (SEP) that implements a threshold-based cluster head (CH) selection for a heterogeneous network. The threshold maintains uniform energy distribution between member and CH nodes. The sensor nodes are also categorized into three different types called normal, intermediate, and advanced depending on the initial energy supply to distribute the network load evenly. The simulation result shows that the proposed scheme outperforms SEP and DEEC protocols with an improvement of 300% in network lifetime and 56% in throughput.

Wireless sensor networks (WSNs) groups specialized transducers that provide sensing services to Internet of Things (IoT) devices with limited energy and storage resources. Since replacement or recharging of batteries in sensor nodes is almost impossible, power consumption becomes one of the crucial design issues in WSN. Clustering algorithm plays an important role in power conservation for the energy constrained network. Choosing a cluster head (CH) can appropriately balance the load in the network thereby reducing energy consumption and enhancing lifetime. This paper focuses on an efficient CH election scheme that rotates the CH position among the nodes with higher energy level as compared to other. The algorithm considers initial energy, residual energy, and an optimum value of CHs to elect the next group of CHs for the network that suits for IoT applications, such as environmental monitoring, smart cities, and systems. Simulation analysis shows the modified version performs better than the low energy adaptive clustering hierarchy protocol by enhancing the throughput by 60%, lifetime by 66%, and residual energy by 64%.

Submitted by Hellen Luz (hellencrisluz@gmail.com) on 2017-08-01T18:31:48Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_ControleEnergeticamenteEficiente.pdf: 1174753 bytes, checksum: 5cd54c6a58e7be0ea1b96f19908312ce (MD5) / Approved for entry into archive by Irvana Coutinho (irvana@ufpa.br) on 2017-08-22T13:01:13Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_ControleEnergeticamenteEficiente.pdf: 1174753 bytes, checksum: 5cd54c6a58e7be0ea1b96f19908312ce (MD5) / Made available in DSpace on 2017-08-22T13:01:13Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_ControleEnergeticamenteEficiente.pdf: 1174753 bytes, checksum: 5cd54c6a58e7be0ea1b96f19908312ce (MD5) Previous issue date: 2014-03-21 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / O presente trabalho objetiva demonstrarum controle centralizado para eleger Cluster Heads (CHs) mais adequados, admitindo trêsníveis de heterogeneidade e uma comunicação de múltiplos saltos entre Cluster Heads. O controle centralizado utiliza o algoritmo k-means, responsável pela divisão dos clusters e Lógica Fuzzy para eleição do Cluster Head e seleção da melhor rota de comunicação entre os eleitos.Os resultados indicam que a proposta apresentada oferece grandes vantagens comparado aos algoritmos anteriores de eleição, permitindo selecionar os nós mais adequados para líderes do grupo a cada round com base nos valores do Sistema Fuzzy, como também, a utilização da Lógica Fuzzy como ferramenta de decisão para implementação de múltiplos saltos entre CHs, uma vez que minimiza a dissipação de energia dos CHs selecionados mais afastados do ponto de coleta. A inserção de três níveis de heterogeneidade, correspondente aos sensores normais, avançados e super sensores, contribui consideravelmente para o aumento do período de estabilidade da rede. Outra grande contribuição obtida a partir dos resultados é a utilização de um controle central na estação base (EB) apresentando vantagens sobre o processamento local de informações em cada nó, processo este encontrado nos algoritmos tradicionais para eleição de CHs.A solução proposta comprovou que a eleição do CH mais eficiente, considerando sua localização e discrepâncias de níveis de energia, como também, na inclusão de novos níveis de heterogeneidade, permite aumentar o período de estabilidade da rede, ou seja, o período que a rede é totalmente funcional, aumentando consideravelmente o tempo de vida útil em Redes de Sensores Sem Fio (RSSF)heterogêneas. / This study presents a centralized control to elect appropriate Cluster Heads (CHs), assuming three levels of heterogeneity and multi-hop communication between Cluster Heads. The centralized control uses the k-means algorithm, responsible for the division of clusters and Fuzzy Logic to elect the Cluster Head and selecting the best route of communication between elected. The results indicate that the proposal offers great advantages, allowing us to select the most suitable nodes for group leaders at each round based on the Fuzzy System values, and also the use of Fuzzy Logic as a decision tool to implement multiple hops between CHs, since it minimizes the power dissipation of the selected CHs more distant from the collection point. The insertion of three levels of heterogeneity,corresponding to normal, advanced and super sensors, contributes considerably to increasing the period of network stability. Another great contribution obtained from the is the use of a central control in base station (BS) with advantages over local information processing in each node, a process usually found in traditional algorithms for electing CHs. The proposed solution proved that the election of the more efficient CH, considering its location and energy levels discrepancies, and also, the inclusion of new heterogeneity levels, allows to increase the networkstability period, ie, the period that the network is fully functional, greatly increasing the useful lifetime in heterogeneous WSN.

Saving energy and increasing network lifetime are significant challenges in the field of Wireless Sensor Networks (WSNs). Energy-aware routing protocols have been introduced for WSNs to overcome limitations of WSN including limited power resources and difficulties renewing or recharging sensor nodes batteries. Furthermore, the potentially inhospitable environments of sensor locations, in some applications, such as the bottom of the ocean, or inside tornados also have to be considered. ZigBee is one of the latest communication standards designed for WSNs based on the IEEE 802.15.4 standard. The ZigBee standard supports two routing protocols, the Ad hoc On-demand Distance Vector (AODV), and the cluster-tree routing protocols. These protocols are implemented to establish the network, form clusters, and transfer data between the nodes. The AODV and the cluster-tree routing protocols are two of the most efficient routing protocols in terms of reducing the control message overhead, reducing the bandwidth usage in the network, and reducing the power consumption of wireless sensor nodes compared to other routing protocols. However, neither of these protocols considers the energy level or the energy consumption rate of the wireless sensor nodes during the establishment or routing processes.

Pour augmenter la durée de vie des réseaux de capteurs sans fil, une solution est d'améliorer l'efficacité énergétique des protocoles de communication. Le regroupement des nœuds du réseau de capteurs sans fil en cluster est l'une des meilleures méthodes. Cette thèse présente propose plusieurs améliorations en modifiant les paramètres du protocole de référence LEACH. Pour améliorer la distribution énergétique des "cluster-heads", nous proposons deux protocoles de clustering centralisés k-LEACH et sa version optimisée k-LEACH-VAR. Un algorithme distribué, appelé e-LEACH, est également proposé pour réduire l'échange d'information périodique entre les nœuds et la station de base lors de l'élection des "cluster-heads". Par ailleurs, le concept l'équilibrage énergétique est introduit dans les métriques d'élection pour éviter les surcharges des nœuds. Ensuite, nous présentons une version décentralisée de k-LEACH qui, en plus des objectifs précédents, intègre la consommation d'énergie globale du réseau. Ce protocole, appelé, k-LEACH-C2D, vise également à favoriser la scalabilité du réseau. Pour renforcer ce dernier et l'autonomie des réseaux, les deux protocoles de routage "multi-hop" probabiliste, dénotés FRSM et CB-RSM construisent des chemins élémentaires entre les "cluster-heads" et la station de base. Le protocole CB-RSM forme une hiérarchie des "cluster-heads" pendant la phase de formation des clusters, en mettant un accent sur l'auto-ordonnancement et l'auto-organisation entre les "cluster-heads" pour rendre les réseaux le plus "scalable". Ces différents protocoles reposent sur l'idée de base que les nœuds ayant l'énergie résiduelle la plus élevée et la plus faible variance de consommation de l'énergie deviennent "cluster-head". Nous constantans le rôle central de la consommation du nœud dans nos différentes propositions. Ce point fera l'objet de la dernière partie de cette thèse. Nous proposons une méthodologie pour caractériser expérimentalement la consommation d'un nœud. Les objectifs visent à mieux appréhender la consommation pour différentes séquences d'état du nœud. Enfin, nous proposons un modèle global de la consommation du nœud. / To increase the lifetime of wireless sensor networks, a solution is to improve the energy efficiency of the communication's protocol. The grouping of nodes in the wireless sensor network clustering is one of the best methods. This thesis proposes several improvements by changing the settings of the reference protocol LEACH. To improve the energy distribution of "cluster-heads", we propose two centralized clustering protocols LEACH and k-optimized version k-LEACH-VAR. A distributed algorithm, called e-LEACH, is proposed to reduce the periodic exchange of information between the nodes and the base station during the election of "cluster-heads". Moreover, the concept of energy balance is introduced in metric election to avoid overloading nodes. Then we presented a decentralized version of k-LEACH, which in addition to the previous objectives, integrates the overall energy consumption of the network. This protocol, called k-LEACH-C2D, also aims to promote the scalability of the network. To reinforce the autonomy and networks, both routing protocols "multi-hop" probability, denoted CB-RSM and FRSM build elementary paths between the "cluster-heads" and elected the base station. The protocol, CB-RSM, forms a hierarchy of "cluster-heads" during the training phase clusters, with an emphasis on self-scheduling and self-organization between "cluster-heads" to make the networks more scalable. These protocols are based on the basic idea that the nodes have the highest residual energy and lower variance of energy consumption become "cluster-head". We see the central role of consumption of the node in our proposals. This point will be the last part of this thesis. We propose a methodology to characterize experimentally the consumption of a node. The objectives are to better understand the consumption for different sequences of the node status. In the end, we propose a global model of the consumption of the node.

Submitted by Irvana Coutinho (irvana@ufpa.br) on 2013-01-23T15:09:34Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_EstrategiaReducaoConsumo.pdf: 2434652 bytes, checksum: bf2428fb8f0caeaf3737a7f0ba4cd7e5 (MD5) / Approved for entry into archive by Ana Rosa Silva(arosa@ufpa.br) on 2013-01-23T17:11:16Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_EstrategiaReducaoConsumo.pdf: 2434652 bytes, checksum: bf2428fb8f0caeaf3737a7f0ba4cd7e5 (MD5) / Made available in DSpace on 2013-01-23T17:11:16Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_EstrategiaReducaoConsumo.pdf: 2434652 bytes, checksum: bf2428fb8f0caeaf3737a7f0ba4cd7e5 (MD5) Previous issue date: 2012 / O avanço nas áreas de comunicação sem fio e microeletrônica permite o desenvolvimento de equipamentos micro sensores com capacidade de monitorar grandes regiões. Formadas por milhares de nós sensores, trabalhando de forma colaborativa, as Redes de Sensores sem Fio apresentam severas restrições de energia, devido à capacidade limitada das baterias dos nós que compõem a rede. O consumo de energia pode ser minimizado, permitindo que apenas alguns nós especiais, chamados de Cluster Head, sejam responsáveis por receber os dados dos nós que formam seu cluster e propagar estes dados para um ponto de coleta denominado Estação Base. A escolha do Cluster Head ideal influencia no aumento do período de estabilidade da rede, maximizando seu tempo de vida útil. A proposta, apresentada nesta dissertação, utiliza Lógica Fuzzy e algoritmo k-means com base em informações centralizadas na Estação Base para eleição do Cluster Head ideal em Redes de Sensores sem Fio heterogêneas. Os critérios usados para seleção do Cluster Head são baseados na centralidade do nó, nível de energia e proximidade para a Estação Base. Esta dissertação apresenta as desvantagens de utilização de informações locais para eleição do líder do cluster e a importância do tratamento discriminatório sobre as discrepâncias energéticas dos nós que formam a rede. Esta proposta é comparada com os algoritmos Low Energy Adaptative Clustering Hierarchy (LEACH) e Distributed energy-efficient clustering algorithm for heterogeneous Wireless sensor networks (DEEC). Esta comparação é feita, utilizando o final do período de estabilidade, como também, o tempo de vida útil da rede. / The increase in wireless communication and microelectronic devices enables the development of micro sensors with monitoring capable for large areas. Consisting of thousands of sensor nodes, working collaboratively, the Wireless sensor networks have severe energy constraints, due to the limited capacity of batteries of the nodes that compose the network. The power consumption can be minimized by allowing only a few special nodes, called Cluster Head, are responsible for receiving data from its cluster nodes that form and propagate this data to a collection point called Base Station. The choice of optimum cluster head influence on increasing the period of stability of the network, maximizing their useful life. The proposal, presented in this thesis, uses Fuzzy Logic and k-means algorithm based on centralized information on Base Station for election of ideal Cluster Head for Heterogeneous Wireless Sensors Networks. The criteria used to select the ideal Cluster Head are based on the node centrality, energy level and proximity to the Base Station. This dissertation presents the disadvantages when the local information are used to the cluster leader election and the importance of discriminatory treatment on the energy discrepancies in the network. This proposal is compared with the Low Energy Adaptive Clustering Hierarchy (LEACH) and Distributed energy-efficient clustering (DEEC) algorithms. This comparison is evaluated using the end of the stability period and the lifetime of the network.