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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Personalised wearable cardiac sensor services for pervasive self-care

Krupaviciute, Asta 20 December 2011 (has links) (PDF)
The aim of the thesis is to design a web services architecture that shall support the automatic determination of a personalised sensor-system, which is embedded in smart garments, and which shall be used in self-care in order to allow a profane user to record himself a personal electrocardiogram (ECG), at anytime and anywhere. The main challenge consists in the intelligent and dynamic orchestration of context-aware business services that supply the user with an optimal personalised solution, while mastering the system's complexity: context dependent user and system interactions, knowledge extraction from subject-specific vital signs, services reconfiguration automation. The solution to this challenge is to create an Ambient Intelligence which goes beyond Ubiquitous Computing and is capable to replace an expert by proposing an Intelligent Assistance to any citizen. We propose a methodology expressed in terms of Data and Model driven Service Oriented Architecture (DM-SOA), which provides a framework for the production of context-aware intelligent business services. This architecture supports the automation of sophisticated and personalised expert activities, which apply professional knowledge to process an individual case. The proposed solution is based on a new dynamic business process modelling approach and in its implementation via automatically reconfigurable services. It consists in setting-up an intelligent environment based on a business process ontology of context-aware concepts and on related context handling rules for services orchestration. A core-ontology has been designed to support the automation of expert activities related to decision-making. The soundness of the method and of the underlying decision-making techniques has been demonstrated in the cardiology domain for selecting the most adequate subject-specific sensor-system, characterised by its ability to yield for an ECG signal of similar diagnostic content than a standard 12-lead ECG. We propose the design of a new three modalities sensor-system prototype as a response to the need of sensor-systems used on demand in self-care situations and ensuring diagnostic quality signals recordings. This prototype has been tested on a set of healthy volunteers presenting various characteristics in age, sex and morphology. In this context, Ambient Intelligence is demonstrated as an ensemble of professional quality services ready to use by profane users. These services are accessible pervasively, trough the objects people work with / wear on / use each day, and provide an appropriate guidance to the non-competent users. Such an Ambient Intelligence approach strongly supports the vision of an Information Society which corresponds to the long-term goal of the EU Information Society Technologies Research Programme that aims to ease knowledge access. The future healthcare will benefit from this approach and will significantly improve patient care.
52

Strategies for context reasoning in assistive livings for the elderly

Tiberghien, Thibaut 18 November 2013 (has links) (PDF)
Leveraging our experience with the traditional approach to ambient assisted living (AAL) which relies on a large spread of heterogeneous technologies in deployments, this thesis studies the possibility of a more "stripped down" and complementary approach, where only a reduced hardware subset is deployed, probing a transfer of complexity towards the software side, and enhancing the large scale deployability of the solution. Focused on the reasoning aspects in AAL systems, this work has allowed the finding of a suitable semantic inference engine for the peculiar use in these systems, responding to a need in this scientific community. Considering the coarse granularity of situational data available, dedicated rule-sets with adapted inference strategies are proposed, implemented, and validated using this engine. A novel semantic reasoning mechanism is proposed based on a cognitively inspired reasoning architecture. Finally, the whole reasoning system is integrated in a fully featured context-aware service framework, powering its context awareness by performing live event processing through complex ontological manipulation. the overall system is validated through in-situ deployments in a nursing home as well as private homes over a few months period, which itself is noticeable in a mainly laboratory-bound research domain
53

Fault-detection in Ambient Intelligence based on the modeling of physical effects.

Mohamed, Ahmed 19 November 2013 (has links) (PDF)
This thesis takes place in the field of Ambient Intelligence (AmI). AmI Systems are interactive systems composed of many heterogeneous components. From a hardware perspective these components can be divided into two main classes: sensors, using which the system observes its surroundings, and actuators, through which the system acts upon its surroundings in order to execute specific tasks.From a functional point of view, the goal of AmI Systems is to activate some actuators, based on data provided by some sensors. However, sensors and actuators may suffer failures. Our motivation in this thesis is to equip ambient systems with self fault detection capabilities. One of the particularities of AmI systems is that instances of physical resources (mainly sensors and actuators) are not necessarily known at design time; instead they are dynamically discovered at run-time. In consequence, one could not apply classical control theory to pre-determine closed control loops using the available sensors. We propose an approach in which the fault detection and diagnosis in AmI systems is dynamically done at run-time, while decoupling actuators and sensors at design time. We introduce a Fault Detection and Diagnosis framework modeling the generic characteristics of actuators and sensors, and the physical effects that are expected on the physical environment when a given action is performed by the system's actuators. These effects are then used at run-time to link actuators (that produce them) with the corresponding sensors (that detect them). Most importantly the mathematical model describing each effect allows the calculation of the expected readings of sensors. Comparing the predicted values with the actual values provided by sensors allows us to achieve fault-detection.
54

The context-aware middleware in ambient intelligence

Xu, Tao 09 December 2013 (has links) (PDF)
Almost 20 years ago, Marc Weiser envisioned the prospect of computer in 21st century, and proposed the pioneering notion of ubiquitous computing. One of Weiser's primary ideas has recently evolved to a more general paradigm known as context awareness, becoming a central research theme in many other ubiquitous computing programs. From Active Badge considered as the first context-aware application, there are numerous attempts to build effective context-aware systems. However, how to acquire context, how to process context and how to create context-aware applications is still faced with enormous challenges in the both of research and practice. This dissertation investigates deeply some chosen key issues in context awareness and develops a context-aware middleware. The main research contributions are presented in three categories: a spatialtemporal context represent model, a context-aware middleware and an intelligence context inference engine. The spatial-temporal context representation model is proposed to organize context and relations for context-aware system. Ontology-based method is adopted to construct our model, supporting both knowledge sharing and reuse as well as logic inference. This model adopts two-layer hierarchy structure for different situation. The higher layer comes up with the generic common context, while the lower layer focuses on various specific situations. Differing from existing models, besides taking locational factors into account, it supports different historical context service depending on different context resource. These context histories may be used to predict and infer the context. A context-aware middleware is designed as a platform associated with context retrieval and context processing. It is organized in two layers: the low layer provides a solution to integrate sensors and actuators with a standardized data representation; the high layer: versatile context interpreter focuses on context processing, which is made up of four parts: Context Aggregator, Inference Engine, Context Knowledge Base, and Query Engine in charge of context inferences, expressive query, and persistent storage. This middleware provides an environment for rapid prototyping of context aware services in ambient intelligent. The intelligent inference engine is the central and intellectual component of context-aware middleware. We review all the methods on activity context recognition published in three premier conferences in past decade and conclude that activity context recognition is divided into three facets: basic activity inference, dynamic activity analysis and future activity recommendation. Then we propose an intelligent inference engine based on our context-aware middleware. Beside satisfying requirements of checking the context consistency, our inference engine integrates the three most popular methods on activity context recognition: Rules, Decision Tree, and Hide Markov Model. It provides a solution for all facets of activity context recognition based on our context-aware middleware. The individuals' information collecting from their social networks under permission are leveraged to train intelligent inference engine. We finally use two scenarios (applications) to explain the generic process to develop application via our middleware, and compare and analyze the main aspects of our middleware with other five representative context-aware applications. Our middleware profits good features from existing context-aware systems and improve intelligence via supporting activity context recognition. It provides an efficient platform for a rapid developing of new context-aware applications in ambient intelligence.
55

Network mobility management for next generation mobile systems

Perera, Algamakoralage Eranga Gayani, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW January 2007 (has links)
The future Internet will need to cater for an increasing number of powerful devices and entire groups of networks to roam in heterogeneous access networks. The current approach towards meeting such requirements, which is to retrofit mobility solutions to different layers of the protocol stack, has given rise to an increasingly fragmented network control layer. Furthermore, retrofitting solutions in an ad-hoc manner to the protocol stack does not provide consistent support from the network to different applications. This lack of a common control layer for facilitating roaming in heterogeneous networking environments represents a crucial challenge both technically and from a user perspective. To this end, a novel mobility architecture forms the basis and the first part of this dissertation. The work on investigating current network mobility solutions and improving these solutions if deemed necessary, in order to reuse within the novel mobility architecture constitutes the second part of this dissertation. The IETF standard protocol for network mobility was implemented and its performance was analysed on a real networking environment. This enabled to identify problems in the standard which affect the handover and routing performance. To address the identified routing and protocol header overheads of the standard network mobility protocol a novel optimal routing framework, OptiNets was proposed. To address the handover latency issues, optimizations to IPv6 network attachment were incorporated and also an access technology independent multiple interface Make-Before-Break handover mechanism was proposed. The viability of the OptiNets framework and the handover optimizations were demonstrated by analysis and by implementation. A more general external factor that affects the performance of mobile networks which is bandwidth scarcity of Wireless Wide Area Networks was addressed, by proposing a bandwidth fuelling architecture for on-board mobile networks. The feasibility of the bandwidth fuelling architecture was analysed by implementing a prototype and evaluating its performance.
56

Designing Sociable Technologies / Design de technologies sociables

Barraquand, Rémi 02 February 2012 (has links)
This thesis investigates the design of sociable technologies and is divided into three main parts described below. In the first part, we introduce sociable technologies. We review our the definition of technology and propose categories of technologies according to the motivation underlying their design: improvement of control, improvement of communication or improvement of cooperation. Sociable technologies are then presented as an extension of techniques to improve cooperation. The design of sociable technologies are then discussed leading to the observation that acquisition of social common sense is a key challenge for designing sociable technologies. Finally, polite technologies are presented as an approach for acquiring social common sense. In the second part, we focus on the premises for the design of sociable technologies. A key aspect of social common sense is the ability to act appropriately in social situations. Associating appropriate behaviour with social situations is presented as a key method for implementing polite technologies. Reinforcement learning is proposed as a method for learning such associations and variation of this algorithm are experimentally evaluated. Learning the association between situation and behaviour relies on the strong assumption that mutual understanding of social situations can be achieved between technologies and people during interaction. We argue that in order to design sociable technologies, we must change the model of communication used by our technologies. We propose to replace the well-known code model of communication, with the ostensive-inferential model proposed by Sperber and Wilson. Hypotheses raised by this approach are evaluated in an experiment conducted in a smart environment, where, subjects by group of two or three are asked to collaborate with a smart environment in order to teach it how to behave in an automated meeting. A novel experimental methodology is presented: The Sorceress of Oz. The results collected from this experiment validate our hypothesis and provide insightful information for the design. We conclude by presenting, what we believe are, the premises for the design of sociable technologies. The final part of the thesis concerns an infrastructure for the design of sociable technologies. This infrastructure provides the support for three fundamental components. First, it provides the support for an inferential model of context. This inferential model of context is presented; a software architecture is proposed and evaluated in an experiment conducted in a smart-environment. Second, it provides the support for reasoning by analogy and introduces the concept of eigensituations. The advantage of this representation are discussed and evaluated in an experiment. Finally, it provides the support for ostensive-inferential communication and introduces the concept of ostensive interface. / This thesis investigates the design of sociable technologies and is divided into three main parts described below. In the first part, we introduce sociable technologies. We review our the definition of technology and propose categories of technologies according to the motivation underlying their design: improvement of control, improvement of communication or improvement of cooperation. Sociable technologies are then presented as an extension of techniques to improve cooperation. The design of sociable technologies are then discussed leading to the observation that acquisition of social common sense is a key challenge for designing sociable technologies. Finally, polite technologies are presented as an approach for acquiring social common sense. In the second part, we focus on the premises for the design of sociable technologies. A key aspect of social common sense is the ability to act appropriately in social situations. Associating appropriate behaviour with social situations is presented as a key method for implementing polite technologies. Reinforcement learning is proposed as a method for learning such associations and variation of this algorithm are experimentally evaluated. Learning the association between situation and behaviour relies on the strong assumption that mutual understanding of social situations can be achieved between technologies and people during interaction. We argue that in order to design sociable technologies, we must change the model of communication used by our technologies. We propose to replace the well-known code model of communication, with the ostensive-inferential model proposed by Sperber and Wilson. Hypotheses raised by this approach are evaluated in an experiment conducted in a smart environment, where, subjects by group of two or three are asked to collaborate with a smart environment in order to teach it how to behave in an automated meeting. A novel experimental methodology is presented: The Sorceress of Oz. The results collected from this experiment validate our hypothesis and provide insightful information for the design. We conclude by presenting, what we believe are, the premises for the design of sociable technologies. The final part of the thesis concerns an infrastructure for the design of sociable technologies. This infrastructure provides the support for three fundamental components. First, it provides the support for an inferential model of context. This inferential model of context is presented; a software architecture is proposed and evaluated in an experiment conducted in a smart-environment. Second, it provides the support for reasoning by analogy and introduces the concept of eigensituations. The advantage of this representation are discussed and evaluated in an experiment. Finally, it provides the support for ostensive-inferential communication and introduces the concept of ostensive interface.
57

Modélisation des connaissances et raisonnement à base d'ontologies spatio-temporelles : application à la robotique ambiante d'assistance / Knowledge modeling and reasoning based on spatio-temporal ontologies : application to ambient assisted-robotics

Ayari, Naouel 15 December 2016 (has links)
Dans cette thèse, nous proposons un cadre générique pour la modélisation et la gestion du contexte dans le cadre des systèmes intelligents ambiants et robotiques. Les connaissances contextuelles considérées sont de plusieurs types et issues de perceptions multimodales : connaissances spatiales et/ou temporelles, changement d’états et de propriétés d’entités, énoncés en langage naturel. Pour ce faire, nous avons proposé une extension du langage NKRL (Narrative Knowledge Representation and Reasoning) pour parvenir à une représentation unifiée des connaissances contextuelles qu’elles soient spatiales, temporelles ou spatio-temporelles et effectuer les raisonnements associés. Nous avons exploité l’expressivité des ontologies n-aires sur lesquelles repose le langage NKRL pour pallier aux problèmes rencontrés dans les approches de représentation des connaissances spatiales et dynamiques à base d’ontologies binaires, communément utilisées en intelligence ambiante et en robotique. Il en résulte une modélisation plus riche, plus fine et plus cohérente du contexte permettant une meilleure adaptation des services d’assistance à l’utilisateur dans le cadre des systèmes intelligents ambiants et robotiques. La première contribution concerne la modélisation des connaissances spatiales et/ou temporelles et des changements de contexte, et les inférences spatiales, temporelles ou spatio-temporelles. La deuxième contribution concerne, quant à elle, le développement d’une méthodologie permettant d’effectuer un traitement syntaxique et une annotation sémantique pour extraire, à partir d’un énoncé en langage naturel, des connaissances contextuelles spatiales ou temporelles en NKRL. Ces contributions ont été validées et évaluées en termes de performances (temps de traitement, taux d’erreurs, et taux de satisfaction des usagers) dans le cadre de scénarios mettant en œuvre différentes formes de services : assistance au bien-être, assistance de type aide sociale, assistance à la préparation d’un repas / In this thesis, we propose a generic framework for modeling and managing the context in ambient and robotic intelligent systems. The contextual knowledge considered is of several types and derived from multimodal perceptions : spatial and / or temporal knowledge, change of states and properties of entities, statements in natural language. To do this, we proposed an extension of the Narrative Knowledge Representation and Reasoning (NKRL) language to reach a unified representation of contextual knowledge whether spatial, temporal or spatio-temporal and perform the associated reasoning. We have exploited the expressiveness of the n-ary ontologies on which the NKRL language is based to bearing on the problems encountered in the spatial and dynamic knowledge representation approaches based on binary ontologies, commonly used in ambient intelligence and robotics. The result is a richer, finer and more coherent modeling of the context allowing a better adaptation of user assistance services in the context of ambient and robotic intelligent systems. The first contribution concerns the modeling of spatial and / or temporal knowledge and contextual changes, and spatial, temporal or spatial-temporal inferences. The second contribution concerns the development of a methodology allowing to carry out a syntactic treatment and a semantic annotation to extract, from a statement in natural language, spatial or temporal contextual knowledge in NKRL. These contributions have been validated and evaluated in terms of performance (processing time, error rate, and user satisfaction rate) in scenarios involving different forms of services: wellbeing assistance, social assistance, assistance with the preparation of a meal
58

Conception d’une architecture de services d’intelligence ambiante pour l’optimisation de la qualité de service de transmission de messages en e-santé / Design of an ambient intelligence services architecture for optimizing quality of service of message transmission in eHealth

Guizani, Nachoua 30 September 2016 (has links)
La gestion de l'acheminement de messages d'e-santé en environnement ubiquitaire soulève plusieurs défis majeurs liés à la diversité et à la spécificité des cas d'usage et des acteurs, à l'évolutivité des contextes médical, social, logistique, environnemental...Nous proposons une méthode originale d'orchestration autonome et auto-adaptative de services visant à optimiser le flux des messages et à personnaliser la qualité de transmission, en les adressant aux destinataires les plus appropriés dans les délais requis. Notre solution est une architecture générique dirigée par des modèles du domaine d'information considéré et des données contextuelles, basés sur l'identification des besoins et des contraintes soulevées par notre problématique.Notre approche consiste en la composition de services de fusion et de gestion dynamique en temps réel d'informations hétérogènes provenant des écosystèmes source, cible et message, pilotés par des méthodes d'intelligence artificielle pour l'aide à la prise de décision de routage. Le but est de garantir une communication fiable, personnalisable et sensible à l'évolution du contexte, quel que soit le scénario et le type de message (alarme, technique, etc.). Notre architecture, applicable à divers domaines, a été consolidée par une modélisation des processus métiers (BPM) explicitant le fonctionnement des services qui la composent.Le cadriciel proposé est basé sur des ontologies et est compatible avec le standard HL7 V3. L'auto-adaptation du processus décisionnel d'acheminement est assurée par un réseau bayésien dynamique et la supervision du statut des messages par une modélisation mathématique utilisant des réseaux de Petri temporels / Routing policy management of eHealth messages in ubiquitous environment leads to address several key issues, such as taking into account the diversity and specificity of the different use cases and actors, as well as the dynamicity of the medical, social, logistic and environmental contexts.We propose an original, autonomous and adaptive service orchestration methodology aiming at optimizing message flow and personalizing transmission quality by timely sending the messages to the appropriate recipients. Our solution consists in a generic, model-driven architecture where domain information and context models were designed according to user needs and requirements. Our approach consists in composing, in real time, services for dynamic fusion and management of heterogeneous information from source, target and message ecosystems, driven by artificial intelligence methods for routing decision support. The aim is to ensure reliable, personalized and dynamic context-aware communication, whatever the scenario and the message type (alarm, technical, etc.). Our architecture is applicable to various domains, and has been strengthened by business process modeling (BPM) to make explicit the services operation.The proposed framework is based on ontologies and is compatible with the HL7 V3 standard. Self-adaptation of the routing decision process is performed by means of a dynamic Bayesian network and the messages status supervision is based on timed Petri nets
59

Raisonnement distribué dans un environnement ambiant / Distributed reasoning in ambient environnement

Jarraya, Amina 16 July 2019 (has links)
L’informatique pervasive et l’intelligence ambiante visent à créer un environnement intelligent avec des dispositifs électroniques et informatiques mis en réseau tels que les capteurs, qui s’intègrent parfaitement dans la vie quotidienne et offrent aux utilisateurs un accès transparent aux services partout et à tout moment.Pour garantir ce fonctionnement, un système doit avoir une connaissance globale sur son environnement, et en particulier sur les personnes et les dispositifs, leurs intérêts et leurs capacités, ainsi que les tâches et les activités associées. Toutes ces informations relèvent de la notion de contexte. Cela passe par la collecte des données contextuelles de l’utilisateur pour déterminer sa situation/son activité courante ; on parle alors d’identification de situations/d’activités. Pour cela, le système doit être sensible aux variations de son environnement et de son contexte, afin de détecter les situations/les activités et de s’adapter ensuite dynamiquement. Reconnaître une situation/une activité nécessite alors la mise en place de tout un processus : perception des données contextuelles, analyse de ces données collectéeset raisonnement sur celles-ci pour l’identification de situations/d’activités.Nous nous intéressons plus particulièrement aux aspects liés à la modélisation distribuée de l’environnement ambiant et à ceux liés au raisonnement distribué en présence de données imparfaites pour l’identification de situations/d’activités. Ainsi, la première contribution de la thèse concerne la partie perception. Nous avons proposé un nouveau modèle de perception permettant la collecte des données brutes issues des capteurs déployés dans l’environnement et la génération des évènements. Ensuite, la deuxième contribution se focalise sur l’observation et l’analyse de ces évènements en les segmentant et extrayant les attributs lesplus significatifs et pertinents. Enfin, les deux dernières contributions présentent deux propositions concernant le raisonnement distribué pour l’identification de situations/d’activités; l’une représente la principale contribution et l’autre représente sa version améliorée palliant certaines limites. D'un point de vue technique, toutes ces propositions ont été développées, validées et évaluées avec plusieurs outils. / Pervasive Computing and Ambient Intelligence aim to create a smart environment withnetworked electronic and computer devices such as sensors seamlessly integrating into everyday life and providing users with transparent access to services anywhere and anytime.To ensure this, a system needs to have a global knowledge of its environment, and inparticular about people and devices, their interests and their capabilities, and associated tasks and activities. All these information are related to the concept of context. This involves gathering the user contextual data to determine his/her current situation/activity; we also talk about situation/activity identification. Thus, the system must be sensitive to environment and context changes, in order to detect situations/activities and then to adapt dynamically.Recognizing a situation/an activity requires the definition of a whole process : perception of contextual data, analysis of these collected data and reasoning on them for the identification of situations/activities.We are particularly interested in aspects related to the distributed modeling of the ambient environment and to those related to distributed reasoning in the presence of imperfect data for the identification of situations/activities. Thus, the first contribution of the thesis concerns the perception part. We have proposed a new perception model that allows the gathering of raw data from sensors deployed in the environment and the generation of events.Next, the second contribution focuses on the observation and analysis of these events by segmenting them and extracting the most significant and relevant features. Finally, the last two contributions present two proposals concerning the distributed reasoning for the identification of situations/activities ; one represents the main contribution and the other represents its improved version overcoming certain limitations. From a technical point of view, all these proposals have been developed, validated and evaluated with several tools.
60

Reinventing The Switch : How Might We Facilitate Adapting Lighting Conditions To Users’ Needs In Homes

Alhalaby, Ghaith January 2022 (has links)
Light shapes the environment we live in and thereby our lives. The advancement in technology made it possible to accurately adjust different light properties. This high level of control is promising and changing at the same time. Taming this complexity and providing users with meaningful ways to interact with light is at the core of this mission. This study seeks ways to facilitate adapting lighting conditions to users’ needs in homes. The answer rests on a synergistic collaboration between the user and the intelligent system, in which the system unobtrusively supports the user through the process of adapting the light. Sustaining the user's agency is crucial, therefore delegating or claiming control should be facilitated and the user should be able to easily comprehend and guide the behaviour of the system. Moreover, user experience should be considered at all levels of attention: focused, peripheral, and implicit. This aims to seamlessly fit the interaction with light in the context of everyday life at home.

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