Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2015-06-05T18:10:26Z No. of bitstreams: 1 MarcusLewisMartinsl.pdf: 1147305 bytes, checksum: 8ab191e523bbdb499dac8c71ef4d9bf9 (MD5) / Made available in DSpace on 2015-06-05T18:10:26Z (GMT). No. of bitstreams: 1 MarcusLewisMartinsl.pdf: 1147305 bytes, checksum: 8ab191e523bbdb499dac8c71ef4d9bf9 (MD5) Previous issue date: 2011-05 / Nenhuma / Este trabalho apresenta o FrameTrail, um framework para o desenvolvimento de aplicações orientadas a trilhas. O FrameTrail se propõe a padronizar a manipulação de trilhas independente do seu domínio de aplicação, ou seja, o framework disponibiliza uma série de funcionalidades que gerenciam a trilha de uma entidade, sem limitar o tipo de contexto e quais os dados específicos das entidades que as aplicações desenvolvidas com base nele manipulam. Além de apresentar os componentes internos da arquitetura do FrameTrail, é também apresentada a estrutura de provedores externos que o framework disponibiliza para que as aplicações possam tratar de trilhas sem a necessidade de seguir um modelo de tecnologia pré-estabelecido. Através desses provedores cada aplicação pode definir quais são as informações relevantes para os seus contextos, assim como permite a parametrização da maneira de como os seus dados serão armazenados. A dissertação também descreve o protótipo desenvolvido do FrameTrail, assim como os estudos de caso desenvolvidos para a sua validação e como eles foram direcionados para aproveitar o melhor as funcionalidades providas pelo framework. / This paper presents the FrameTrail, a framework for developing trail oriented applications. The FrameTrail aims to standardize the manipulation of trails regardless of its scope. The framework provides a number of features that manage the entity’s trail, without limiting the type of context and what the specifics information of the entities that applications developed based on this can handle. We present the internal components of the architecture of FrameTrail and also presents the structure of external providers. This external providers provides the framework so that applications can address the trails without the need to follow a technology model pre-established. Each of these providers can define which information relevant to their contexts, as well as lets you customize the way of how your data will be stored. The dissertation also describes the prototype of FrameTrail, as well as case studies designed to validate him and how they were directed to use the most of the functionalities provided by the framework.

Um dos principais desafios de pesquisa na UbiComp consiste em fornecer mecanismos para a ciência de contexto que promovam o desenvolvimento de aplicações que reajam de acordo com a dinâmica do ambiente de interesse do usuário. Para manter o conhecimento a respeito desse ambiente, a área da UbiComp pressupõe a utilização de informações produzidas e disponibilizadas em diferentes localizações, o tempo todo. Nesse sentido, os recentes avanços na área da Internet das Coisas (IoT) têm proporcionado uma crescente disponibilidade de sensores conectados em rede, os quais são potenciais produtores de informações contextuais do ambiente para aplicações ubíquas. Com essa motivação, nessa tese é apresentado o COIOT, um middleware para Internet das Coisas concebido com o objetivo de gerenciar a coleta e o processamento das informações contextuais do ambiente físico, bem como a atuação remota sobre o mesmo. O COIOT foi idealizado considerando os trabalhos previamente desenvolvidos pelo grupo de pesquisa GPPD (Grupo de Processamento Paralelo e Distribuído) da UFRGS, particularmente o middleware EXEHDA (Execution Environment for Highly Distributed Applications). Na concepção do COIOT foi adotada uma abordagem distribuída de processamento de contexto que contempla tanto as premissas da IoT quanto as demandas das aplicações da UbiComp. A arquitetura proposta também contempla o gerenciamento de eventos distribuídos através de regras e triggers para tratar as mudanças de estados dos contextos de interesse. Além disso, a arquitetura proposta gerencia outros aspectos importantes nos cenários da IoT, como o tratamento da interoperabilidade, da heterogeneidade, apoio ao controle da escalabilidade e descoberta de recursos. As principais contribuições desta tese são: (i) a concepção de uma arquitetura para IoT capaz de realizar de forma distribuída tanto a coleta e processamento das informações contextuais, como a atuação remota no meio a fim de atender as aplicações da UbiComp e, (ii) a proposição de um modelo de processamento de eventos distribuídos adequado aos cenários da IoT. Para avaliar a arquitetura do COIOT foram realizados dois estudos de caso na área da agricultura. O primeiro estudo de caso foi desenvolvido em ambiente de produção a partir de demandas de pesquisadores da área da agricultura, particularmente da análise de sementes. Já o segundo estudo de caso teve como cenário de testes ambientes da viticultura de precisão. / One of the main research challenges in UbiComp is to provide mechanisms for context-aware to promote the development of applications that react according to the dynamics of user interest environment. To keep the knowledge of this environment, the area of UbiComp presupposes the use of information produced and made available in different locations, all the time. In this sense, the recent advances in the field of Internet of Things (IoT) have provided an increasing availability of sensors and actuators networked. These sensors are potential producers of contextual information. With this motivation, this thesis is presented the CoIoT, a middleware for Internet of Things (IoT) designed in order to manage the collect and processing of contextual information of the physical environment as well as remote actuation on it. The CoIoT was designed considering the work previously developed by the research group GPPD (Parallel Processing Group and distributed) of UFRGS, particularly middleware EXEHDA (Execution Environment for Highly Distributed Applications). In designing the CoIoT it was adopted a distributed approach of context processing that includes both the principles of IoT as the demands of the applications of UbiComp. The proposed architecture also includes rules based and triggers mechanisms to deal with events that characterize the changes of states of the contexts of interest. In addition, the proposed architecture manages other important aspects of IoT scenarios such as the treatment of interoperability, heterogeneity, support the control of scalability and resource discovery. Until now, the central contributions of this thesis include: (i) the design of an architecture for IoT able to perform distributed way both the collect and processing of contextual information, such as remote actuation in the environment in order to meet UbiComp applications and, (ii) the proposition of a distributed event processing model appropriate to the IoT scenarios. In order to evaluate the CoIoT architecture, two case studies were carried out in the area of agriculture. The first case study was developed in a production environment based on the demands of agricultural researchers, particularly seed analysis. On the other hand, the second case study was based on precision testing of viticulture environments.

Wireless ad-hoc networks are based on a cooperative communication model, where all nodes not only generate traffic but also help to route traffic from other nodes to its final destination. In such an environment where there is no infrastructure support the lifetime of the network is tightly coupled with the lifetime of individual nodes. Most of the devices that form such networks are battery-operated, and thus it becomes important to conserve energy so as to maximize the lifetime of a node. In this thesis, we present JTP, a new energy-aware transport protocol, whose goal is to reduce power consumption without compromising delivery requirements of applications. JTP has been implemented within the JAVeLEN system. JAVeLEN~\cite{javelen08redi}, is a new system architecture for ad hoc networks that has been developed to elevate energy efficiency as a first-class optimization metric at all protocol layers, from physical to transport. Thus, energy gains obtained in one layer would not be offset by incompatibilities and/or inefficiencies in other layers. To meet its goal of energy efficiency, JTP (1) contains mechanisms to balance end-to-end vs. local retransmissions; (2) minimizes acknowledgment traffic using receiver regulated rate-based flow control combined with selected acknowledgments and in-network caching of packets; and (3) aggressively seeks to avoid any congestion-based packet loss. Within this ultra low-power multi-hop wireless network system, simulations and experimental results demonstrate that our transport protocol meets its goal of preserving the energy efficiency of the underlying network. JTP has been implemented on the actual JAVeLEN nodes and its benefits have been demoed on a real system.

Com os avanços dos processos da microeletrônica temos dispositivos menores e com maior poder de computação e comunicação. Um Ambiente Pervasivo contém diferentes dispositivos, tais como sensores, atuadores, eletroeletrônicos e dispositivos móveis que interagem com a pessoa de forma natural ao conhecer o contexto. A diversidade de dispositivos e informações do Ambiente Pervasivo introduz um problema de interoperabilidade. Um Ambiente Pervasivo é dinâmico devido à mobilidade do usuário, a variedade de dispositivos. Neste trabalho, é proposto um modelo semântico de contexto para permitir interoperabilidade e fornecer suporte ao dinamismo do Ambiente Pervasivo. O modelo proposto contém características da modelagem de contexto realizadas por trabalhos anteriores, assim como sua integração com a modelagem de preferências das pessoas, políticas de privacidade e serviços. Verificou-se que o modelo de contexto proposto é adequado mediante sua aplicação em um Estudo de Caso e mediante testes realizados. Mostra-se que a modelo de contexto utilizado ontologias e Serviços Web Semânticos permite tratar com informação incompleta e inconsistente, bem como fornece suporte na interoperabilidade e ao dinamismo do Ambiente Pervasivo. / Advances in microelectronic processes have allowed smaller devices with more computation and communication power. Pervasive environment contains different devices like electronic sensor, actuators and mobile devices which interact with the person naturally after the context is known. The device and information diversity introduce an interoperability problem. Pervasive environments are dynamics because of user\'s mobility and a variety of devices. In this work, we propose a context model to allow interoperability and to give support to pervasive environment dynamism. The proposed model contains features of context modeling developed in previous works, as well as, their integration with the modeling of the people\'s preferences, privacy policies and services. It was verified that the context model is appropriate by their application in a Case Study and by accomplished tests. It is shown that the model of context using ontologies and Semantic Web Services allow us to work with inconsistent and incomplete information, as well as gives support to interoperability and dynamism of the Pervasive Environment.

Demand response is one of the critical technologies necessary for allowing large-scale penetration of intermittent renewable energy sources in the electric grid. Data centers are especially attractive candidates for providing flexible, real-time demand response services to the grid because they are capable of fast power ramp-rates, large dynamic range, and finely-controllable power consumption. This thesis makes a contribution toward implementing load shaping with server clusters through a detailed experimental investigation of three broadly-applicable datacenter workload scenarios. We experimentally demonstrate the eminent feasibility of datacenter demand response with a distributed video transcoding application and a simple distributed power controller. We also show that while some software power capping interfaces performed better than others, all the interfaces we investigated had the high dynamic range and low power variance required to achieve high quality power tracking. Our next investigation presents an empirical performance evaluation of algorithms that replace arithmetic operations with low-level bit operations for power-aware Big Data processing. Specifically, we compare two different data structures in terms of execution time and power efficiency: (a) a baseline design using arrays, and (b) a design using bit-slice indexing (BSI) and distributed BSI arithmetic. Across three different datasets and three popular queries, we show that the bit-slicing queries consistently outperform the array algorithm in both power efficiency and execution time. In the context of datacenter power shaping, this performance optimization enables additional power flexibility -- achieving the same or greater performance than the baseline approach, even under power constraints. The investigation of read-optimized index queries leads up to an experimental investigation of the tradeoffs among power constraint, query freshness, and update aggregation size in a dynamic big data environment. We compare several update strategies, presenting a bitmap update optimization that allows improved performance over both a baseline approach and an existing state-of-the-art update strategy. Performing this investigation in the context of load shaping, we show that read-only range queries can be served without performance impact under power cap, and index updates can be tuned to provide a flexible base load. This thesis concludes with a brief discussion of control implementation and summary of our findings.

Propelled by the explosive increases in mobile data traffic volume, existing wireless technologies are stretched to their capacity limits. There is a tremendous need for an expansion in system capacity and an improvement on energy efficiency. In addition, wireless network will support more and more multimedia services and applications, in which user experience has been always an important factor in evaluating the overall network performance. In order to keep pace with this explosion of data traffic and to meet the emerging quality of experience needs, wireless heterogeneous networks have been introduced as a promising network architecture evolution of the traditional cellular network. In this dissertation, we explore video quality-aware spectrum efficiency and energy efficiency in wireless heterogeneous networks|the potentials and the associated technical challenges. In particular, aiming to significantly enhance spectrum efficiency, we need to tackle the interference issue, which is exacerbated in heterogeneous network due to ultra dense node deployment as well as heterogeneity nature of various nodes. Specifically, werst study an optimal intra-cell inter-tier cooperation to mitigate interference between high power nodes and low power nodes. Together with cooperation, optimal mobile association and resource allocation schemes are also intensively investigated in heterogeneous network to achieve system load balancing so that bandwidth at high power and low power nodes can be utilized in the optimal way. The proposed scheme can greatly alleviate inter-tier interference and significantly increase overall system spectrum efficiency in a heterogeneous network. We then further apply advanced algorithms such as precoding, and non-orthogonal multiple access into intra-cell inter-tier cooperation so that the overall system spectrum efficiency and user experience are even more improved. When supporting a video type application in such a heterogeneous network, considering only spectrum efficiency is far from enough as video application is bandwidth consuming, battery consuming, and quality demanding. We develop a video quality-aware spectrum and energy efficiency resource allocation scheme in a wireless heterogeneous network and propose novel performance metrics to establish fundamental relationships among spectrum efficiency, energy efficiency, and quality of experience. Extensive simulations are conducted to evaluate the trade-o performance among three performance metrics.

We present the high level (VHDL) modeling and high level synthesis of an ASIC (TOUR NAVIGATOR) for a portable hand held device - a tour guide. The tour guide is based on location-aware mobile computing, which gives the information of the current location to the user. The TOUR NAVIGATOR designed in this work is interfaced with off-the-shelf components to realise the tour guide system. The current location is given by an on-board GPS receiver chip. The TOUR NAVIGATOR is a search and play module which interfaces with the flash memory, GPS receiver and the audio codec. The functionality of the TOUR NAVIGATOR is to search the flash memory for audio data corresponding to the current GPS co-ordinate, which is an input to the TOUR NAVIGATOR. The look-up table containing the GPS coordinates and the corresponding audio files are loaded into the flash memory, where in each GPS entry in the table is indexed by the co-ordinates, and an audio file that contains information about the locations is associated with it. When there is a match, the audio file is streamed to the codec. The functionality of the interface of the TOUR NAVIGATOR with the memory module is verified at the RTL using Cadence-NCLaunch. The layout implementation of the TOUR NAVIGATOR is done using an automatic place and route tool (Silicon Ensemble), which uses standard cells for the entire design. Leakage power reduction is done by introducing sleep transistors in the standard cells. The TOUR NAVIGATOR is put into a "sleep" mode when there is no operation of the tour guide, thus giving significant power savings.

Aujourd'hui, l'hétérogénéité des infrastructures de réseaux actuelles, ainsi que le manque d'interopérabilité en termes d'architectures et de cadres pour l'adaptation du contenu aux contextes des différents utilisateurs, empêchent les Prosumers (consommateurs-fournisseurs) d’offrir une haute qualité d'expérience sur différentes plates-formes et au travers de contextes diversifiés. Par conséquent, l'objectif de cette thèse est d'étudier, concevoir et développer une architecture novatrice, susceptible d'offrir la QoS/QoE garantie en exploitant efficacement les ressources disponibles et en adaptant dynamiquement la performance du réseau selon les environnements Réseau, Service et Utilisateur. Pour cela, l'architecture proposée est basée sur (1) un cadre de gestion distribuée qui exploite des mécanismes de réseau conscient du contenu pour identifier le contenu en transit et la correspondance sur les exigences de QoS/QoE, et sur (2) un mécanisme d'allocation des ressources de réseau et leur adaptation aux caractéristiques de QoS/QoE demandées. Un prototype de routeur de contenu a été réalisé, offrant des fonctions de reconnaissance du type de contenu et de routage suivant le contenu. Il propose un système de gestion synergique capable d'orchestrer les processus d'optimisation cross-layer pour les services de différenciation/classification et à termes une exploitation efficace des ressources. La validité de l'architecture proposée est vérifiée par un grand nombre d'expériences menées à l'aide d’infrastructures physiques et virtuelles. Un banc d'essai à grande échelle conforme aux spécifications de conception architecturale a été déployé pour valider l'approche proposée. / Today, the heterogeneity of current networking infrastructures, along with the lack of interoperability in terms of architectures and frameworks for adapting content to the various users’ contexts, prevent prosumers to deliver high QoE over different platforms and under diversified contexts. Consequently, the objective of this PhD thesis is to study, design, and develop a novel architecture capable to offer guaranteed QoS/QoE by efficiently exploiting the available resources and by dynamically adapting the network performance across the various Service, Network and User environments. To this end, the proposed architecture is based on (1) a distributed management framework that exploits Content Aware Network (CAN) mechanisms – on top of the Internet Protocol (IP) – for identifying content in transit and mapping its QoS/QoE requirements into specific network characteristics, and on (2) a network resource allocation mechanism for adapting the intra-domain resources to the requested QoS/QoE. A prototype Media-Aware Network Element (MANE) has been achieved, offering content type recognition and content-based routing/forwarding as a matter of guaranteed QoS/QoE provision in an end-to-end approach. Furthermore, it proposes a synergetic management system capable to orchestrate cross-layer optimization processes for service differentiation/classification, towards efficient resource exploitation. The validity of the proposed architecture is verified through a large number of experiments conducted using physical and virtual infrastructures. A large-scale test-bed conforming to the architectural design specifications was deployed for validating the proposed approach.

Air pollution is a severe issue in many big cities due to population growth and the rapid development of the economy and industry. This leads to the proliferating need to monitor urban air quality to avoid personal exposure and to make savvy decisions on managing the environment. In the last decades, the Internet of Things (IoT) is increasingly being applied to environmental challenges, including air quality monitoring and visualization. In this thesis, we present CAVisAP, a context-aware system for outdoor air pollution visualization with IoT platforms. The system aims to provide context-aware visualization of three air pollutants such as nitrogen dioxide (NO2), ozone (O3) and particulate matter (PM2.5) in Melbourne, Australia and Skellefteå, Sweden. In addition to the primary context as location and time, CAVisAP takes into account users’ pollutant sensitivity levels and colour vision impairments to provide personalized pollution maps and pollution-based route planning. Experiments are conducted to validate the system and results are discussed.

University of Technology, Sydney. Faculty of Information Technology. / Over the last few years Peer-to-Peer (P2P) systems have emerged as highly attractive systems supporting many useful large-scale applications and services. They allow the exploitation of enormous untapped resources (such as idle processing cycles, storage, and bandwidth) available at Internet-connected devices, which were previously considered incapable of providing services to others. Participating nodes (peers) form an overlay network and communicate with each other without being controlled by a central authority. The structures and routing decisions of the most current P2P networks often do not correlate with the Internet infrastructure. In doing so, the tasks of overlay construction and routing become less complicated however, this results in high end-to-end delay for the P2P applications. As a consequence, the P2P networks may not be able to provide stringent Quality of Service (QoS) requirements for a new generation of P2P applications, and thus limit their benefits for the end users. Moreover, the infrastructure ignorance means P2P systems waste Internet resources by adding more than they should to the Internet traffic. This leads to the increase in Internet access costs substantially, and in turn the P2P systems do not scale well. The thesis presents a novel architecture for developing efficient P2P systems, and new schemes for constructing infrastructure-aware overlay networks. The main objective is first, to overcome the disparity between the overlay and Internet structures in order to maximize the use of network resources and reduce the overlay delay to the P2P applications; second, to provide efficient communication for P2P systems enabling deployment of any P2P applications while preserving decentralized, self-organizing and self-maintaining characteristics for the systems. To achieve these goals, we firstly developed Geographically Longest Prefix Matching (Geo-LPM) and Geographical Partitioning (Geo-Partitioning) schemes to cluster nodes that are close to each other in terms of network latency and network membership, and to determine links between neighboring clusters respectively. The developed schemes are efficient, generate low overhead, and help to produce excellent physically/infrastructure-aware overlay networks. Their distinctive features are self-organization, self-maintenance, and decentralization, which make them suitable to work in a P2P environment. Secondly we propose a novel architecture, called a physically-aware reference model (PARM) that captures desirable features for P2P systems by resolving major functional P2P system problems efficiently in a layered structure. For example, the application routing layer of PARM deals with routing inefficiency, meanwhile the infrastructure unawareness is resolved at the overlay network layer. We develop a useful P2P application, called a Peer Name Service (PNS) that interprets node names into their current IP addresses for any Internet-connected devices. Using the overlay networks, the PNS can support devices, which could be unreachable via the Domain Name Server (DNS), and mobile devices on-the-move without prior setup requirement in a distributed and timely fashion. Finally, to validate the whole concept of PARM, we simulate the PNS and a file transfer to a mobile node at the top layer of PARM, the P2P application layer. Since the PNS is sensitive to delay, it would be useful to evaluate the impacts of overlay delay factor and PARM on the performance of P2P applications. The simulation results show that the performance of the PARM-based applications is significantly improved while achieving decentralized and self-organizing features. The results also indicate that PARM can be a recommended reference model for developing scalable and efficient P2P systems.