Dissertations / Theses on the topic 'Ubiquitous sensor network'

Ubiquitous Sensor Network (USN) est un réseau conceptuel construit sur des réseaux physiques existantes. Il se sert des données détectées et fournit des services de connaissances à quiconque, n'importe où et à tout moment, et où l'information est générée en utilisant la sensibilité au contexte. Dispositifs et USN portables intelligents émergent rapidement en offrant de nombreux services fiables facilitant la vie des gens. Ces petits terminaux et terminaux très utiles besoin d'un substrat de communication globale pour fournir un service complet de l'utilisateur final global. En 2010, ITU -T a fourni les exigences pour supporter des applications et services USN dans le Next Generation Network (NGN) de l'environnement d'exploiter les avantages du réseau de base. L'un des principaux marchés prometteurs pour l'application et les services USN est la e- santé. Il fournit le suivi des patients en continu et permet une grande amélioration dans les services médicaux. D'autre part, des Véhicules Ad-hoc NETwork (VANET) est une technologie émergente qui permet une communication intelligente entre les véhicules mobiles. Intégrer VANET avec USN a un grand potentiel pour améliorer la sécurité routière et la fluidité du trafic. La plupart des applications VANET sont appliqués en temps réel et ils sont sensibles à retarder, en particulier ceux liés à la sécurité et à la santé. Dans ce travail, nous proposons d'utiliser l'IP Multimédia Subsystem (IMS) comme une sous- couche de contrôle de service dans l'environnement USN fournir un substrat mondiale pour un service complet de bout en bout. De plus, nous vous proposons d'intégrer VANETs avec USN pour des applications et des installations riches plus, ce qui facilitera la vie des humains. Nous avons commencé à étudier les défis sur la route pour atteindre cet objectif<br>Ubiquités Sensor Network (USN) is a conceptual network built over existing physical networks. It makes use of sensed data and provides knowledge services to anyone, anywhere and at anytime, and where the information is generated by using context awareness. Smart wearable devices and USNs are emerging rapidly providing many reliable services facilitating people life. Those very useful small end terminals and devices require a global communication substrate to provide a comprehensive global end user service. In 2010, the ITU-T provided the requirements to support USN applications and services in the Next Génération Network (NGN) environment to exploit the advantages of the core network. One of the main promising markets for the USN application and services is the e-Health. It provides continuous patients’ monitoring and enables a great improvement in medical services. On the other hand, Vehicular Ad-Hoc NETwork (VANET) is an emerging technology, which provides intelligent communication between mobile vehicles. Integrating VANET with USN has a great potential to improve road safety and traffic efficiency. Most VANET applications are applied in real time and they are sensitive to delay, especially those related to safety and health. In this work, we propose to use IP Multimedia Subsystem (IMS) as a service controller sub-layer in the USN environment providing a global substrate for a comprehensive end-to-end service. Moreover, we propose to integrate VANETs with USN for more rich applications and facilities, which will ease the life of humans. We started studying the challenges on the road to achieve this goal

Ubiquitous Sensor Network (USN) est un réseau conceptuel construit sur des réseaux physiques existantes. Il se sert des données détectées et fournit des services de connaissances à quiconque, n'importe où et à tout moment, et où l'information est générée en utilisant la sensibilité au contexte. Dispositifs et USN portables intelligents émergent rapidement en offrant de nombreux services fiables facilitant la vie des gens. Ces petits terminaux et terminaux très utiles besoin d'un substrat de communication globale pour fournir un service complet de l'utilisateur final global. En 2010, ITU -T a fourni les exigences pour supporter des applications et services USN dans le Next Generation Network (NGN) de l'environnement d'exploiter les avantages du réseau de base. L'un des principaux marchés prometteurs pour l'application et les services USN est la e- santé. Il fournit le suivi des patients en continu et permet une grande amélioration dans les services médicaux. D'autre part, des Véhicules Ad-hoc NETwork (VANET) est une technologie émergente qui permet une communication intelligente entre les véhicules mobiles. Intégrer VANET avec USN a un grand potentiel pour améliorer la sécurité routière et la fluidité du trafic. La plupart des applications VANET sont appliqués en temps réel et ils sont sensibles à retarder, en particulier ceux liés à la sécurité et à la santé. Dans ce travail, nous proposons d'utiliser l'IP Multimédia Subsystem (IMS) comme une sous- couche de contrôle de service dans l'environnement USN fournir un substrat mondiale pour un service complet de bout en bout. De plus, nous vous proposons d'intégrer VANETs avec USN pour des applications et des installations riches plus, ce qui facilitera la vie des humains. Nous avons commencé à étudier les défis sur la route pour atteindre cet objectif<br>Ubiquités Sensor Network (USN) is a conceptual network built over existing physical networks. It makes use of sensed data and provides knowledge services to anyone, anywhere and at anytime, and where the information is generated by using context awareness. Smart wearable devices and USNs are emerging rapidly providing many reliable services facilitating people life. Those very useful small end terminals and devices require a global communication substrate to provide a comprehensive global end user service. In 2010, the ITU-T provided the requirements to support USN applications and services in the Next Génération Network (NGN) environment to exploit the advantages of the core network. One of the main promising markets for the USN application and services is the e-Health. It provides continuous patients’ monitoring and enables a great improvement in medical services. On the other hand, Vehicular Ad-Hoc NETwork (VANET) is an emerging technology, which provides intelligent communication between mobile vehicles. Integrating VANET with USN has a great potential to improve road safety and traffic efficiency. Most VANET applications are applied in real time and they are sensitive to delay, especially those related to safety and health. In this work, we propose to use IP Multimedia Subsystem (IMS) as a service controller sub-layer in the USN environment providing a global substrate for a comprehensive end-to-end service. Moreover, we propose to integrate VANETs with USN for more rich applications and facilities, which will ease the life of humans. We started studying the challenges on the road to achieve this goal

Abstract This dissertation aimed at developing a multi-modal sensing u-healthcare system (MSUS), which reflects the unique properties of a healthcare application in a wireless sensor network. Together with health parameters, such as ECG, SpO2 and blood pressure, the system also transfers context-aware data, including activity, position and tracking data, in a wireless sensor network environment at home or in a hospital. Since packet loss may have fatal consequences for patients, health-related data are more critical than most other types of monitoring data. Thus, compared to environmental, agricultural or industrial monitoring, healthcare monitoring in a wireless environment imposes different requirements and priorities. These include heavy data traffic with wavelike parameters in wireless sensor network and fatal data loss due to the traffic. To ensure reliable data transfer in a wireless sensor network, this research placed special emphasis on the optimization of sampling rate, packet length and transmission rate, and on the traffic reduction method. To improve the reliability and accuracy of diagnosis, the u-healthcare system also collects context-aware information on the user’s activity and location and provides real-time tracking. Waveform health parameters, such as ECG, are normally sampled in the 100 to 400 Hz range according to the monitoring purpose. This type of waveform data may incur a heavy burden in wireless communication. To reduce wireless traffic between the sensor nodes and the gateway node, the system utilizes on-site ECG analysis implemented on the sensor nodes as well as query architecture. A 3D VRML viewer was also developed for the realistic monitoring of the user’s moving path and location. Two communication methods, an 802.15.4-based wireless sensor network and a CDMA cellular network are used by sensors placed on the users’ bodies to gather medical data, which is then transmitted to a server PC at home or in the hospital, depending on whether the sensor is within or outside the range of the wireless sensor network.

La recente esplosione di tecnologie quali Pervasive Computing e IoT ha fatto sı̀ che, negli ultimi anni, da una parte facessero ingresso nelle nostre vite dispositivi in grado di interagire con l’ambiente circostante grazie ai sensori di cui sono dotati che permettono di eseguire continue rilevazioni di numerosi tipi di dati, dall’altra che molti oggetti, anche di uso comune, venissero dotati di tecnologie di comunicazione e che divenissero capaci di comunicare in internet. Questo, oltre a portare molteplici benefici in numerosi campi di applicazione, ha generato un forte interesse dal punto di vista commerciale e numerosi produttori in tutto il mondo si sono lanciati in questo mercato. Non esistendo un criterio di comunicazione condiviso da tutti, questo ha determinato che dal punto di vista tecnologico la situazione si andasse cosı̀ a frammentare. L’obiettivo di questo studio è di illustrare come l’integrazione di un modello di trust possa fornire una valida soluzione al problema dell’eterogeneità e alla bassa qualità dei dati rilevati dovuta al basso costo dei dispositivi coinvolti. Contestualmente apporta numerosi benefici all’efficenza del sistema in termine di ottimizzazione delle risorse e di attuazione di strategie di identificazione degli errori.

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2005.<br>Includes bibliographical references (p. 97-101).<br>This research presents novel techniques for acoustic-source location for both actively triggered, and passively detected signals using pervasive, distributed networks of devices, and investigates the combination of existing resources available in personal electronics to build a digital sensing 'commons'. By connecting personal resources with those of the people nearby, tasks can be achieved, through distributed placement and statistical improvement, that a single device could not do alone. The utility and benefits of spatio-temporal acoustic sensing are presented, in the context of ubiquitous computing and machine listening history. An active audio self-localisation algorithm is described which is effective in distributed sensor networks even if only coarse temporal synchronisation can be established. Pseudo-noise 'chirps' are emitted and recorded at each of the nodes. Pair-wise distances are calculated by comparing the difference in the audio delays between the peaks measured in each recording. By removing dependence on fine grained temporal synchronisation it is hoped that this technique can be used concurrently across a wide range of devices to better leverage the existing audio sensing resources that surround us.<br>(cont.) A passive acoustic source location estimation method is then derived which is suited to the microphone resources of network-connected heterogeneous devices containing asynchronous processors and uncalibrated sensors. Under these constraints position coordinates must be simultaneously determined for pairs of sounds and recorded at each microphone to form a chain of acoustic events. It is shown that an iterative, numerical least-squares estimator can be used. Initial position estimates of the source pair can be first found from the previous estimate in the chain and a closed-form least squares approach, improving the convergence rate of the second step. Implementations of these methods using the Smart Architectural Surfaces development platform are described and assessed. The viability of the active ranging technique is further demonstrated in a mixed-device ad-hoc sensor network case using existing off-the-shelf technology. Finally, drawing on human-centric onset detection as a means of discovering suitable sound features, to be passed between nodes for comparison, the extension of the source location algorithm beyond the use of pseudo-noise test sounds to enable the location of extraneous noises and acoustic streams is discussed for further study.<br>Benjamin Christopher Dalton.<br>S.M.

A new class of wireless sensor networks has recently appeared due to the pervasiness of cellular phones with embedded sensors, mobile Internet connectivity, and location technologies. This mobile wireless sensor network has the potential to address large-scale societal problems and improve the people's quality of life in a better, faster and less expensive fashion than current solutions based on static wireless sensor networks. Ubiquitous Sensing is the umbrella term used in this dissertation that encompasses location-based services, human-centric, and participatory sensing applications. At the same time, ubiquitous sensing applications are bringing a new series of challenging problems. This dissertation proposes and evaluates G-Sense, for Global-Sense, an architecture that integrates mobile and static wireless sensor networks, and addresses several new problems related to location-based services, participatory sensing, and human-centric sensing applications. G-Sense features the critical point algorithms, which are specific mechanisms to reduce the power consumption by continous sensing applications in cellular phones, and reduce the amount of data generated by these applications. As ubiquitous sensing applications have the potential to gather data from many users around the globe, G-Sense introduces a peer-to-peer system to interconnect sensing servers based on the locality of the data. Finally, this dissertation proposes and evaluates a multiobjective model and a hybrid evolutionary algorithm to address the efficient deployment of static wireless sensor nodes when monitoring critical areas of interest.

This thesis focuses on the study of low-resource demanding protocols, communication techniques and software solutions to evaluate, optimise and implement Web service in WSNs. We start analysing the Web service architectures in order to choose the most appropriate for the constraints of WSNs, which is REST. Based on this analysis, we review the state-of-the-art of protocols that allows implementing REST Web services. To this end, we adopt the IEEE 802.15.4 standard for the physical and data-link layers, 6LoWPAN for the network layer and CoAP for the application layer. 6LoWPAN defines two forwarding techniques, which are called mesh under (MU) and route over (RO). It also provides a mechanism to fragment packets, which is called 6LoWPAN fragmentation. In part of the thesis, we study the effects that MU and RO have on communications using 6LoWPAN fragmentation. In particular, MU does not prevent forwarding unnecessary fragments and out-of-order delivery, which could lead to an inefficient use of bandwidth and a growth of energy consumption. We propose, then, a novel technique able to improve the performance of MU with fragmented packets, which we refer to as controlled mesh under (CMU). The results of a performance evaluation in a real WSN show that CMU is able to enhance the performance of MU by reducing its packet loss and end-to-end delay. In 6LoWPAN fragmentation, the loss of a fragment forces the retransmission of the entire packet. To overcome this limitation, CoAP defines blockwise transfer. It splits the packet into blocks and sends each one in reliable transactions, which introduces a significant communication overhead. We propose a novel analytical model to study blockwise and 6LoWPAN fragmentation, which is validated trough Monte Carlo simulations. Both techniques are compared in terms of reliability and delay. The results show that 6LoWPAN fragmentation is preferable for delay-constrained applications. For highly congested networks, blockwise slightly outperforms 6LoWPAN fragmentation in terms of reliability. CoAP defines the observe option to allow a client to register to a resource exposed by a server and to receive updates of its state. Existing QoS in the observe option supports partially timeliness. It allows specifying the validity of an update but it does not guarantee its on-time delivery. This approach is inefficient and does not consider applications, i.e. e-health, that requires the delivery of an update within a deadline. With this limitation in mind, we design and evaluate a novel mechanism for update delivery based on priority. The evaluation proves that implementing a delivery order improves the delay and delivery ratio of updates. Our proposal is also able to reduce the energy consumption allowing clients to express the class of updates that they wish to receive. In part of this thesis, we present our original library for TinyOS, which we referred to as TinyCoAP, and the design and implementation of a CoAP proxy. We compare TinyCoAP to CoapBlip, which is the CoAP implementation distributed with TinyOS. TinyCoAP proves to be able to reach a high code optimization and to reduce the impact over the memory of WSN nodes. The evaluation includes also the analysis of the CoAP reliability mechanism, which was still uncovered in the literature. As a novelty, we also compare CoAP with HTTP considering different solutions for the transport layer protocol such as UDP and persistent TCP connections. The CoAP proxy enables Web applications to transparently access the resources hosted in CoAP devices. It supports long-lived communications by including the WebSocket protocol. It also supports Web applications that use the traditional HTTP long-polling technique. Finally, one of the main contributions of the proxy design is the proposal of a standard URI path format to be used by Web applications to access to a CoAP resource.<br>Esta tesis se enfoca en el estudio de protocolos de bajo consumo, técnicas de comunicación y software con el fin de evaluar, optimizar y desarrollar servicios Web en WSNs. Empezamos analizando la arquitectura de servicios Web con el objetivo de elegir la arquitectura más apropiada debido a las limitaciones de WSNs. Ésta se denomina REST. En base a este análisis, revisamos el estado del arte de los protocolos que permiten desarrollar servicios Web. Con este objetivo adoptamos el estándar IEEE 802.15.4 por la capa física y de enlace, 6LoWPAN por la de red y CoAP por la capa de aplicación. 6LoWPAN define dos técnicas de enrutamiento, denominadas 'Mesh Under' (MU) y 'Route Over' (RO). Asimismo ofrece un mecanismo para fragmentar paquetes, llamado 6LoWPAN fragmentation. En parte de la tesis estudiamos los efectos que MU y RO tienen sobre la comunicación que utiliza 6LoWPAN fragmentation. En particular, MU no previene enrutar fragmentos innecesarios y la entrega fuera de orden, lo cual podría provocar un uso ineficiente de ancho de banda y un crecimiento del consumo energía. Proponemos entonces nueva técnica capaz de mejorar las prestaciones de MU con paquetes fragmentados que denominamos 'Controlled Mesh Under' (CMU). Los resultados de una evaluación en una WSN real demuestran que CMU es capaz de mejorar las prestaciones de MU reduciendo la pérdida de paquetes y el retraso end-to-end. En 6LoWPAN fragmentation, la pérdida de un fragmento causa la retransmisión del paquete entero. Para evitar esta limitación CoAP define blockwise transfer. Esto divide el paquete en bloques y los envía en comunicaciones fiables provocando overhead. Proponemos un nuevo modelo analítico para estudiar blockwise y 6LoWPAN fragmentation cuya validación se realiza mediante simulaciones de Monte Carlo. Ambas técnicas se comparan en términos de fiabilidad y retraso. Los resultados muestran que es preferible usar 6LoWPAN fragmentation para las aplicaciones con restricciones en retraso. Para las redes mas congestionadas, blockwise mejora ligeramente 6LoWPAN fragmentation en términos de fiabilidad. CoAP define la opción observe para permitir a un cliente registrarse a un recurso proporcionado por un servidor y recibir actualizaciones de su estado. La QoS ofrecida por la opción observe proporciona soporte parcial por el timeliness. Esta permite especificar la validez de una actualización pero no garantiza su entrega a tiempo. Este enfoque es ineficiente y no incluye aplicaciones, como por ejemplo e-health que requieren la entrega de las actualizaciones en un plazo determinado. Teniendo en cuenta esta limitación, diseñamos y evaluamos un mecanismo novedoso para la entrega de actualizaciones basada en la prioridad. La evaluación demuestra que la implementación de una orden de entrega mejora la tasa de llegada y el retraso de las actualizaciones. Nuestra propuesta es capaz de reducir el consumo de energía permitiendo a los clientes expresar el tipo de actualización que desean recibir. En parte de esta tesis presentamos nuestra librería original pro TinyOS a la que nos referimos como TinyCoAP, así como el diseño y desarrollo de un Proxy CoAP. Comparamos TinyCoAP a CoapBlip, que es la aplicación distribuida con TinyOS. TinyCoAP demuestra ser capaz de alcanzar una alta optimización de código y reducir el impacto sobre la memoria de nodos de WSNs. La evaluación también incluye el análisis de la fiabilidad de CoAP que no había sido estudiada en la literatura. Como novedad también comparamos CoAP con HTTP, considerando diferentes soluciones para el protocolo de transporte como UDP y conexiones TCP persistentes. El Proxy CoAP permite a las aplicaciones Web acceder de manera transparente a los recursos almacenados en dispositivos CoAP. Éste incluye el protocolo WebSocket, que permite el establecimiento de conexiones long-lived. También permite el uso de aplicaciones Web con la tradicional técnica HTTP long-polling

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada<br>Industrial wireless sensor networks can be designed to meet the strict requirements of specific distributed applications. Emerging standards have enabled the development of low-cost, lowpower sensor nodes that are quickly becoming a commodity, enabling the realization of efficient and reliable data acquisition and telemetry in many systems. Moreover, new and exciting possibilities arise from the distributed computing power of the sensor nodes, the ability to monitor and aggregate data across large arrays of sensors, and the ability to model dynamic and rugged environments that were previously beyond the reach of traditional data acquisition and telemetry systems.

Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2010.<br>Page 232 blank. Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 222-231).<br>In today's digital era, elements of anyone's life can be captured, by themselves or others, and be instantly broadcast. With little or no regulation on the proliferation of camera technology and the increasing use of video for social communication, entertainment, and education, we have undoubtedly entered the age of ubiquitous media. A world permeated by connected video devices promises a more democratized approach to mass-media culture, enabling anyone to create and distribute personalized content. While these advancements present a plethora of possibilities, they are not without potential negative effects, particularly with regard to privacy, ownership, and the general decrease in quality associated with minimal barriers to entry. This dissertation presents a first-of-its-kind research platform designed to investigate the world of ubiquitous video devices in order to confront inherent problems and create new media applications. This system takes a novel approach to the creation of user-generated, documentary video by augmenting a network of video cameras integrated into the environment with on-body sensing. The distributed video camera network can record the entire life of anyone within its coverage range and it will be shown that it, almost instantly, records more audio and video than can be viewed without prohibitive human resource cost.<br>(cont.) This drives the need to develop a mechanism to automatically understand the raw audiovisual information in order to create a cohesive video output that is understandable, informative, and/or enjoyable to its human audience. We address this need with the SPINNER system. As humans, we are inherently able to transform disconnected occurrences and ideas into cohesive narratives as a method to understand, remember, and communicate meaning. The design of the SPINNER application and ubiquitous sensor platform is informed by research into narratology, in other words how stories are created from fragmented events. The SPINNER system maps low level sensor data from the wearable sensors to higher level social signal and body language information. This information is used to label the raw video data. The SPINNER system can then build a cohesive narrative by stitching together the appropriately labeled video segments. The results from three test runs are shown, each resulting in one or more automatically edited video piece. The creation of these videos is evaluated through review by their intended audience and by comparing the system to a human trying to perform similar actions. In addition, the mapping of the wearable sensor data to meaningful information is evaluated by comparing the calculated results to those from human observation of the actual video.<br>by Mathew Laibowitz.<br>Ph.D.

Advances in wireless technologies and the rapid development of integrated electronics have made wireless sensor networks (WSN) one of the key technologies of the Internet of Things (IoT). Thanks to the ability of these networks to measure the physical phenomena of their environment, process and communicate this information using wireless technologies, they have excelled in the development of applications that respond or adapt to the context of a user, as is the case of ubiquitous environments such as smart cities, industrial automation, e-health among others. In addition, the IoT has opened the possibility that intelligent objects or devices are also capable of exchanging status information, conditions and capacity in order to interact with each other, in the same way that human beings have done through systems based on presence. These systems require information of an event in real time to react in a timely manner to the conditions or context of the user or device. These applications open new challenges in the management of WSN resources, since these networks operate in environments that are generally prone to packet loss and consist of generally small nodes with limited resources in memory, processing, bandwidth and power. The main objective of this thesis is the development of several mechanisms that allow the adaptation of the Publish/Subscribe protocols to the characteristics and limitations of the WSN for the provision of ubiquitous services in the context of the IoT. In addition, QoS support is supplied through mechanisms that provide reliability and timeliness in the delivery of packets and data aggregation techniques are applied to be efficient in the power consumption and the WSN bandwidth. Our research proposes an architecture to provide a presence service for WSN based on a Publish/ Subscribe model distributed and focused on mechanisms such as the aggregation of data and the publication of messages on demand to achieve energy efficiency and bandwidth. All these mechanisms have been applied in the design of a system called PASH aimed at home control based on the concept of Ambient Assisted Living (AAL). The reliability provided by Publish/Subscribe protocols in WSN is of great importance in the design of applications that require receiving a message to react on time or in real time to an event. Initially, we focused our study on increasing the proportion of packet delivery (PDR) in the destination node through the improvement of reliability mechanisms. We evaluated the reliability mechanism of the MQTT-SN protocol and several proposed mechanisms of the CoAP protocol. From this evaluation, we propose a new and simple adaptive retransmission mechanism to respond to packet loss in the most appropriate way. Finally, we consider that applications such as: e-health, critical infrastructure control and monitoring, among others, must meet different QoS requirements, such as reliability and timeliness for each type of message received. In addition, data aggregation techniques play an important role in WSN to reduce power consumption and bandwidth. In this thesis, we propose a mechanism that provides the application with three different levels of QoS: we provide an improvement of our previous relay mechanism for reliability, we include the data aggregation in our reliability mechanism and we provide a timeliness mechanism in the delivery of packets.<br>Els avenços en les tecnologies sense fils i al ràpid desenvolupament de l'electrònica integrada, ha convertit les xarxes de sensors sense fils (WSN) en una de les tecnologies claus de l'Internet de les Coses (Iot). Gràcies a la capacitat que tenen aquestes xarxes de mesurar els fenòmens físics del seu entorn, processar i comunicar aquesta informació utilitzant tecnologies sense fils, s'han destacat en el desenvolupament d'aplicacions que responguin o s'adaptin al context d'un usuari, com és el cas dels entorns ubics com a ciutats intel·ligents, automatització industrial, salut electrònica entre d'altres. A més, el IOT ha obert la possibilitat que els objectes o dispositius intel·ligents també siguin capaços d'intercanviar informació d'estat, condicions i capacitat per tal d'interactuar entre si, de la mateixa manera que els éssers humans ho han fet a través de sistemes basats en presència. Aquests sistemes requereixen informació d'un esdeveniment en temps real per reaccionar de manera oportuna a les condicions o al context de l'usuari o dispositiu. Aquestes aplicacions obren nous desafiaments en l'administració dels recursos de WSN, ja que aquestes xarxes operen en entorns que generalment són propensos a la pèrdua de paquets i consten de nodes generalment petits amb recursos limitats en memòria, processament, ample de banda i alimentació. El principal objectiu d'aquesta tesi és el desenvolupament de diversos mecanismes que permetin l'adequació dels protocols d'Publish / Subscribe a les característiques i limitacions de la WSN per a la provisió de serveis ubics en el context de la IOT. A més, es brinda suport de QoS a través de mecanismes que proporcionen fiabilitat i puntualitat en el lliurament de paquets i s'apliquen tècniques d'agregació de dades per a ser eficients en el consum d'energia i l'ample de banda de la WSN. La nostra investigació proposa una arquitectura per a proporcionar un servei de presència per WSN basat en un model de Publish / Subscribe distribuït i centrat en mecanismes com ara l'agregació de dades i la publicació de missatges en demanda per aconseguir eficiència en l'energia i l'ample de banda . Tots aquests mecanismes han estat aplicats en el disseny d'un sistema anomenat Pash dirigit al control de la llar basat en el concepte de Vida Assistida (AAL). La fiabilitat proporcionada pels protocols de Publish / Subscribe WSN és de gran importància en el disseny d'aplicacions que requereixen rebre un missatge per reaccionar a temps o en temps real davant un esdeveniment. Inicialment enfoquem el nostre estudi en augmentar la proporció de lliurament de paquets (PDR) en el node de destinació a través de la millora dels mecanismes de fiabilitat. Avaluem el mecanisme de fiabilitat del protocol MQTT-SN i diversos mecanismes proposats del protocol COAP. A partir d'aquesta avaluació, proposem un nou i senzill mecanisme de retransmissió adaptable per respondre a la pèrdua de paquets de la manera més adequada. Finalment, considerem que les aplicacions com: salut electrònica, control d'infraestructura crítica i monitoratge, entre d'altres, han de complir diferents requisits de QoS, com la fiabilitat i la puntualitat per a cada tipus de missatge rebut. A més, les tècniques d'agregació de dades tenen un paper important en WSN per reduir el consum d'energia i l'ample de banda. En aquesta tesi, proposem un mecanisme que proporciona a la aplicació tres nivells de QoS diferents: proporcionem una millora del nostre mecanisme de retransmissió anterior per a la fiabilitat, incloem l'agregació de dades en el nostre mecanisme de fiabilitat i proporcionem un mecanisme de puntualitat en el lliurament de paquets.

Cette thèse explore la reconnaissance de gestes à partir de capteurs inertiels pour Smartphone. Ces gestes consistent en la réalisation d'un tracé dans l'espace présentant une valeur sémantique, avec l'appareil en main. Notre étude porte en particulier sur l'apprentissage de métrique entre signatures gestuelles grâce à l'architecture "Siamoise" (réseau de neurones siamois, SNN), qui a pour but de modéliser les relations sémantiques entre classes afin d'extraire des caractéristiques discriminantes. Cette architecture est appliquée au perceptron multicouche (MultiLayer Perceptron). Les stratégies classiques de formation d'ensembles d'apprentissage sont essentiellement basées sur des paires similaires et dissimilaires, ou des triplets formés d'une référence et de deux échantillons respectivement similaires et dissimilaires à cette référence. Ainsi, nous proposons une généralisation de ces approches dans un cadre de classification, où chaque ensemble d'apprentissage est composé d’une référence, un exemple positif, et un exemple négatif pour chaque classe dissimilaire. Par ailleurs, nous appliquons une régularisation sur les sorties du réseau au cours de l'apprentissage afin de limiter les variations de la norme moyenne des vecteurs caractéristiques obtenus. Enfin, nous proposons une redéfinition du problème angulaire par une adaptation de la notion de « sinus polaire », aboutissant à une analyse en composantes indépendantes non-linéaire supervisée. A l'aide de deux bases de données inertielles, la base MHAD (Multimodal Human Activity Dataset) ainsi que la base Orange, composée de gestes symboliques inertiels réalisés avec un Smartphone, les performances de chaque contribution sont caractérisées. Ainsi, des protocoles modélisant un monde ouvert, qui comprend des gestes inconnus par le système, mettent en évidence les meilleures capacités de détection et rejet de nouveauté du SNN. En résumé, le SNN proposé permet de réaliser un apprentissage supervisé de métrique de similarité non-linéaire, qui extrait des vecteurs caractéristiques discriminants, améliorant conjointement la classification et le rejet de gestes inertiels<br>As consumer devices become more and more ubiquitous, new interaction solutions are required. In this thesis, we explore inertial-based gesture recognition on Smartphones, where gestures holding a semantic value are drawn in the air with the device in hand. In our research, speed and delay constraints required by an application are critical, leading us to the choice of neural-based models. Thus, our work focuses on metric learning between gesture sample signatures using the "Siamese" architecture (Siamese Neural Network, SNN), which aims at modelling semantic relations between classes to extract discriminative features, applied to the MultiLayer Perceptron. Contrary to some popular versions of this algorithm, we opt for a strategy that does not require additional parameter fine tuning, namely a set threshold on dissimilar outputs, during training. Indeed, after a preprocessing step where the data is filtered and normalised spatially and temporally, the SNN is trained from sets of samples, composed of similar and dissimilar examples, to compute a higher-level representation of the gesture, where features are collinear for similar gestures, and orthogonal for dissimilar ones. While the original model already works for classification, multiple mathematical problems which can impair its learning capabilities are identified. Consequently, as opposed to the classical similar or dissimilar pair; or reference, similar and dissimilar sample triplet input set selection strategies, we propose to include samples from every available dissimilar classes, resulting in a better structuring of the output space. Moreover, we apply a regularisation on the outputs to better determine the objective function. Furthermore, the notion of polar sine enables a redefinition of the angular problem by maximising a normalised volume induced by the outputs of the reference and dissimilar samples, which effectively results in a Supervised Non-Linear Independent Component Analysis. Finally, we assess the unexplored potential of the Siamese network and its higher-level representation for novelty and error detection and rejection. With the help of two real-world inertial datasets, the Multimodal Human Activity Dataset as well as the Orange Dataset, specifically gathered for the Smartphone inertial symbolic gesture interaction paradigm, we characterise the performance of each contribution, and prove the higher novelty detection and rejection rate of our model, with protocols aiming at modelling unknown gestures and open world configurations. To summarise, the proposed SNN allows for supervised non-linear similarity metric learning, which extracts discriminative features, improving both inertial gesture classification and rejection

Thesis (Ph.D.)--Computing, Georgia Institute of Technology, 2009.<br>Committee Chair: Abowd, Gregory; Committee Member: Edwards, Keith; Committee Member: Grinter, Rebecca; Committee Member: LaMarca, Anthony; Committee Member: Starner, Thad.

Made available in DSpace on 2016-06-02T19:05:57Z (GMT). No. of bitstreams: 1 4452.pdf: 7806002 bytes, checksum: 03f3df43afda775ba6b11c313093d1d5 (MD5) Previous issue date: 2012-06-13<br>Financiadora de Estudos e Projetos<br>The physical inactivity has been indicated by the World Health Organization (WHO) as one of the main risk factors for the incidence of Chronic Non-Communicable Diseases (CNCDs). Millions of deaths in the world are a result of these diseases, and this number has increased each year. In an attempt to change this scenario WHO has stimulated regular practice of physical activities, because they play an important role in preventing CNCDs. In Brazil, these activities are performed by health units which generate a large amount of data that need treatment. To deal with this problem we developed UCEMEPA, an environment that employs Ubiquitous Computing technologies and wireless communication networks, in order to monitor remotely and evaluate participants of physical activity groups in real-time. This environment automatically collects physiologic data, and provides indicators which will support and direct public policies for promoting physical activity. In this sense, UCEMEPA will contribute for the promotion of health and quality of life, and for the conduction of longitudinal studies aiming to establish correlations between the practice of physical activity and CNCDs prevention.<br>A inatividade física tem sido apontada pela Organização Mundial de Saúde (OMS) como um dos principais fatores de risco comportamentais responsáveis pela incidência de Doenças Crônicas Não Transmissíveis (DCNTs). Milhões de mortes no mundo são decorrentes dessas doenças e esse número vem aumentando a cada ano. Na tentativa de reverter esse quadro a OMS vem estimulando as práticas regulares de atividade física, já que estas possuem um importante papel na prevenção de DCNTs. No Brasil a promoção dessas atividades é realizada por unidades regionalizadas de saúde e geram uma grande quantidade de dados que carecem de processamento e tratamento. Em resposta a esse problema nós desenvolvemos o ACUMAAF, um ambiente que emprega tecnologias emergentes da Computação Ubíqua e redes de comunicação sem fio para monitorar e avaliar, em tempo real e a distância, participantes de grupos de atividade física. Esse ambiente coleta dados fisiológicos de forma automática e coletiva e tem como objetivo possibilitar a geração de indicadores capazes de apoiar e nortear políticas públicas de promoção de atividade física. O ACUMAAF é um ambiente computacional com contribuições para a promoção da saúde, para a promoção da qualidade de vida da população e para a realização de estudos longitudinais objetivando relacionar atividade física e a prevenção de DCNTs.

La plupart des réseaux de capteurs sans fill d’aujourd’hui fonctionne sur le protocole CSMA/CA. Fournir la qualité de service (QdS) dans un tel réseau est un problème difficile compte tenu de la dynamique du réseau et des contraintes en termes de ressources (énergie et mémoire). Dans cette thèse, sans changer le socle commun du CSMA/CA, nous avons proposé des mécanismes auto-adaptatifs qui permettent de gérer la QdS "best-effort" pour des applications nécessitant de la différenciation de services. Trois mécanismes sont proposés : CoSenS pour "Collecting then Sending burst Scheme", P-CoSenS qui a joute la gestion de priorités à CoSenS, et S-CoSenS qui a joute la dimension énergie à CoSenS. La dynamique du réseau est prise en compte grâce à l’auto-adaptation de périodes de collecte et de transmission en rafale. Il est à souligner que le mécanisme CoSenS permet non seulement d’améliorer les performances de CSMA/CA mais aussi de surmonter la difficulté d’ordonnancer les trafics entrant dans un nœud (routeur) car chaque paquet entrant est immédiatement retransmis vers la sortie. En effet, grâce à la pério de de collecte, les paquets entrants sont mis en file d’attente, rendant ainsi possible d’ordonnancer différemment les paquets selon leur priorité (P-CoSenS). Enfin, le compromis énergie/performance est pris en compte dans S-CoSenS. Selon l’état de l’environnement surveillé, le réseau peut se trouver dans une période où circule un trafic non urgent et souvent faible pendant laquelle il est judicieux de minimiser la consommation d’énergie et une pério de de trafic important pendant laquelle le réseau doit transporter des données urgentes pour suivre une situation alarmante de plus près. Comme CoSenS, S-CoSenS permet de s’auto-adapter dynamiquement en fonction de ces situations. L’ensemble de nos propositions est validé par simulations et CoSenS est implémenté sur une plateforme de réseau de capteurs<br>Nowadays, most of wireless sensor networks use CSMA/CA protocol. Providing quality of service (QoS) support in such networks is a difficult problem because of the network dynamics and the high constraints in terms of resources like energy and memory. In this thesis and without changing the basic access protocol, CSMA/CA, we developed auto-adaptive mechanisms for best-effort QoS targeted to applications requiring differentiation services. Three mechanisms are proposed; CoSenS for "Collecting then Sending burst Scheme" which enhances the performances of CSMA/CA, P-CoSenS for "Priority CoSenS" which adds priority management to CoSenS and S-CoSenS for "S-CoSenS" which tackles energy efficiency using CoSenS. We emphasize that CoSenS mechanism not only enhances the performance of CSMA/CA in terms of throughput, end-to-end delay and successful transmission rates but enables also the implementation of scheduling policies; since the router collects and queues paquets before retransmitting them, it has a complete knowledge about them and can then schedule them efficiently (P-CoSenS). S-CoSenS tackles the energy/throughput tradeoff. In fact, the state of a network varies according to the monitored environment. The network may be at some times lightly loaded with non urgent traffic and at other times highly loaded with urgent traffic generated by nodes in order to monitor a happening phenomenon more closely and hence take the best decision. In the former case, the network must save energy. In the latter case, it must provide bandwidth. S-CoSenS auto-adapts its sleeping and active periods according the incoming traffic. Our propositions are validated by simulations and CoSenS is implemented on a wireless sensor platform

La plupart des réseaux de capteurs sans fill d'aujourd'hui fonctionne sur le protocole CSMA/CA. Fournir la qualité de service (QdS) dans un tel réseau est un problème difficile compte tenu de la dynamique du réseau et des contraintes en termes de ressources (énergie et mémoire). Dans cette thèse, sans changer le socle commun du CSMA/CA, nous avons proposé des mécanismes auto-adaptatifs qui permettent de gérer la QdS "best-effort" pour des applications nécessitant de la différenciation de services. Trois mécanismes sont proposés : CoSenS pour "Collecting then Sending burst Scheme", P-CoSenS qui a joute la gestion de priorités à CoSenS, et S-CoSenS qui a joute la dimension énergie à CoSenS. La dynamique du réseau est prise en compte grâce à l'auto-adaptation de périodes de collecte et de transmission en rafale. Il est à souligner que le mécanisme CoSenS permet non seulement d'améliorer les performances de CSMA/CA mais aussi de surmonter la difficulté d'ordonnancer les trafics entrant dans un nœud (routeur) car chaque paquet entrant est immédiatement retransmis vers la sortie. En effet, grâce à la pério de de collecte, les paquets entrants sont mis en file d'attente, rendant ainsi possible d'ordonnancer différemment les paquets selon leur priorité (P-CoSenS). Enfin, le compromis énergie/performance est pris en compte dans S-CoSenS. Selon l'état de l'environnement surveillé, le réseau peut se trouver dans une période où circule un trafic non urgent et souvent faible pendant laquelle il est judicieux de minimiser la consommation d'énergie et une pério de de trafic important pendant laquelle le réseau doit transporter des données urgentes pour suivre une situation alarmante de plus près. Comme CoSenS, S-CoSenS permet de s'auto-adapter dynamiquement en fonction de ces situations. L'ensemble de nos propositions est validé par simulations et CoSenS est implémenté sur une plateforme de réseau de capteurs.

In networked robot systems (NRS), robots and robotic devices are distributed in the environment; typically tasks are performed by cooperation and coordination of such multiple networked components. NRS offer advantages over monolithic systems in terms of modularity, flexibility and cost effectiveness, and they are thus becoming a mainstream approach to the inclusion of robotic solutions in everyday environments. The components of a NRS are usually robots and sensors equipped with rich computational and communication facilities. In this thesis, we argue that the capabilities of a NRS would greatly increase if it could also accommodate among its nodes simpler entities, like small ubiquitous sensing and actuation devices, home appliances, or augmented everyday objects. For instance, a domestic robot needs to manipulate food items and interact with appliances. Such a robot would benefit from the ability to exchange information with those items and appliances in a direct way, in the same way as with other networked robots and sensors. Combining such highly heterogeneous devices inside one NRS is challenging, and one of the major challenges is to provide a common communication and collaboration infrastructure. In the field of NRS, this infrastructure is commonly provided by a shared middleware. Unfortunately, current middlewares lack the generality needed to allow heterogeneous entities such as robots, simple ubiquitous devices and everyday objects to coexist in the same system. In this thesis we show how an existing middleware for NRS can be extended to include three new types of “citizens” in the system, on peer with the other robots. First, we include computationally simple embedded devices, like ubiquitous sensors and actuators, by creating a fully compatible tiny version of the existing robotic middleware. Second, we include augmented everyday objects or home appliances which are unable to run the middleware on board, by proposing a generic design pattern based on the notion of object proxy. Finally,we go one step further and include humans as nodes in the NRS by defining the notion of human proxy. While there exist a few other NRS which are able to include both robots and simple embedded devices in the same system, the use of proxies to include everyday objects and humans in a generic way is a unique feature of this work. In order to verify and validate the above concepts, we have implemented them in the Peis-Ecology NRS model. We report a number of experiments based on this implementation, which provide both quantitative and qualitative evaluations of its performance, reliability, and interoperability.

Potentially transformational ideas in several applications of human and computer interaction form the motivation for this work. It is targeted towards a systematic approach to the design of systems with complex, intelligent and interactive exchange of information between a system and the environment it is meant to monitor, and gather knowledge about. The Pahl and Beitz systematic design method is modified with the inclusion of generic sub-systems from Living Systems Theory, modeling and simulation tools and other adaptations within the context of the validation square to synthesize a design method for the design of systems with intelligent and interactive information flow. The validation of the proposed design method is carried out with the aid of an example wherein a motion capture system is designed based on the Nintendo Wii Remote(TM). Results include an evaluation of the performance of a prototype as well as the design method itself in the context of the requirements that the method must fulfill.

Internet of Things (IoT) will create the opportunity to develop new types of businesses. Every tangible object, biologic or not, will be identified by a unique address, creating a common network composed by billions of devices. Those devices will have different requirements, creating the necessity of finding new mechanisms to satisfy the needs of all the entities within the network. This is one of the main problems that all the scientific community should address in order to make Internet of Things the Future Internet. Currently, IoT is used in a lot of projects involving Wireless Sensor Networks (WSNs). Sensors are generally cheap and small devices able to generate useful information from physical indicators. They can be used on smart home scenarios, or even on healthcare environments, turning sensors into useful devices to accomplish the goals of many use case scenarios. Sensors and other devices with some reasoning capabilities, like smart objects, can be used to create smart environments. The interaction between the objects in those scenarios and humans can be eased by the inclusion of Intelligent Personal Assistants (IPAs). Currently, IPAs have good reasoning capabilities, improving the assistance they give to their owners. Artificial intelligence (AI), new learning mechanisms, and the evolution assisted in speech technology also contributed to this improvement. The integration of IPAs in IoT scenarios can become a case of great success. IPAs will comprehend the behavior of their owners not only through direct interactions, but also by the interactions they have with other objects in the environment. This may create ubiquitous communication scenarios where humans act as passive elements, being adequately informed of all the aspects of interest that surrounds them. The communication between IPAs and other objects in their surrounding environment may use gateways for traffic forwarding. On ubiquitous environments devices can be mobile or static. For example, in smart home scenarios, objects are generally static, being always on the same position. In mobile health scenarios, objects can move from one place to another. To turn IPAs useful on all types of environments, static and mobile gateways should be developed. On this dissertation, a novel mobile gateway solution for an IPA platform inserted on an IoT context is proposed. A mobile health scenario was chosen. Then, a Body Sensor Network (BSN) is always monitoring a person, giving the real time feedback of his/her health status to another person responsible by him (designated caretaker). On this scenario, a mobile gateway is needed to forward the traffic between the BSN and the IPA of the caretaker. Therefore, the IPA is able to give warnings about the health status of the person under monitoring, in real time. The proposed system is evaluated, demonstrated, and validated through a prototype, where the more important aspects for IPAs and IoT networks are considered.

Wireless Sensor Networks (WSNs) belongs to a new technology trend where tiny and resource constrained devices are wirelessly interconnected and are able to interact with the surrounding environment by collecting data, such as temperature and humidity. Recently, due to the huge growth of mobile devices usage with Internet connection, smartphones are becoming the center of future ubiquitous wireless networks allowing users to access data network services, anytime and anywhere. According to the Internet of Things vision, interconnecting WSNs with smartphones and the Internet is a big challenge. Then, due to the heterogeneity of these devices new architectures are required. This dissertation focuses on the design and construction of a ubiquitous architecture for WSNs monitoring based on Web services, a relational database, and an Android mobile application. This architecture allows mobile users accessing real-time or historical data in a ubiquitous environment using smartphones. Besides that, a push notification system to alert mobile users when a sensor parameter overcomes a given threshold was created. The entire solution was evaluated and demonstrated using a laboratory WSN testbed, and is ready for use.<br>As redes de sensores sem fios fazem parte de uma nova tendência tecnológica na qual pequenos dispositivos com recursos limitados comunicam entre si, sem fios, e interagem com o ambiente envolvente recolhendo uma grande diversidade de dados, tais como a temperatura e a humidade. Recentemente, devido ao enorme crescimento no uso de dispositivos móveis com ligação à Internet, os smartphones estão a tornar-se o centro das futuras redes sem fios ubíquas permitindo aos utilizadores aceder a dados, a qualquer hora e em qualquer lugar. De acordo com a visão da Internet of Things, interligar redes de sensores sem fios e smartphones usando a Internet é um grande desafio e novas arquitecturas são necessárias devido à heterogeneidade destes dispositivos. Esta dissertação centra-se na proposta e construção de uma arquitectura ubíqua para a monitorização de redes de sensores sem fios, baseada em serviços Web, apoiada numa base de dados relacional e uma aplicação móvel para o sistema operative Android. Esta arquitectura permite que os utilizadores móveis acedam a dados em tempo real e também a dados históricos, num ambiente móvel, usando smartphones. Além disso, foi desenvolvido um sistema de notificações push que alerta o utilizador quando um dado parâmetro de um sensor ultrapassa um limiar pré-definido. A solução construída foi testada e demonstrada utilizando uma testbed laboratorial e está pronta para utilização.

This thesis proposes a DIY environmental sensing approach that empowers citizens to reinvigorate people's awareness of, and concern for, pollution. Current air pollution measuring techniques are described, and a new concept of participatory sensing is presented. I argue that technological advances in sensing, computation, storage, and communication now have the power to turn the near-ubiquitous mobile phone into a global mobile sensing device, and commence the participatory paradigm employing amateurs in environmental data collection. To test the thesis, PAIR, a prototype with interchangeable sensor, was developed. It aims to enable people to sense environment on-the-go and provide users with immediate feedback. Such data can make people learn about their environment, make them aware of air pollution causes, and eventually even bring behavioral changes. Consequently, a user survey and interviews identify strengths and weaknesses of the mobile sensing device, and based on the usability requirements, we conclude design recommendations for further development. Finally, we identify the main benefits amateur data collection and participatory sensing represent for urban dwellers, and we evaluate issues and challenges they have yet to overcome.

Indiana University-Purdue University Indianapolis (IUPUI)<br>With the advances in embedded technology and the omnipresence of smartphones, tracking systems do not need to be confined to a specific tracking environment. By introducing mobile devices into a tracking system, we can leverage their mobility and the availability of multiple sensors such as camera, Wi-Fi, Bluetooth and Inertial sensors. This thesis proposes to improve the existing tracking systems, enhanced Distributed Tracking System (e-DTS 2.0) [19] and enhanced Distributed Object Tracking System (eDOTS)[26], in the form of e-DTS 3.0 and provides an empirical analysis of these improvements. The enhancements proposed are to introduce Android-based mobile devices into the tracking system, to use multiple sensors on the mobile devices such as the camera, the Wi-Fi and Bluetooth sensors and inertial sensors and to utilize possible resources that may be available in the environment to make the tracking opportunistic. This thesis empirically validates the proposed enhancements through the experiments carried out on a prototype of e-DTS 3.0.