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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.
221

Egocentric interaction for ambient intelligence

Surie, Dipak January 2012 (has links)
Ambient intelligence refers to the vision of computationally augmented everyday environments that are sensitive, adaptive and responsive to humans and intelligently support their daily lives. Ambient ecologies are the infrastructures of ambient intelligence. To enable system developers to frame and manage the dynamic and complex interaction of humans with ambient ecologies consisting of a mixture of physical (real) and virtual (digital) objects, novel interaction paradigms are needed. Traditional interaction paradigms like the WIMP (windows, icon, menus, and pointing devices) paradigm for desktop computing operate in a closed world, unaware of the physical, social and cultural context. They restrict human perception and action to screen, mouse and keyboard with the assumption that human attention will be fully devoted to interaction with the computer. Emerging interaction paradigms for ambient intelligence are typically centered on specific devices, specific computing environments or specific human capabilities. Also, many of them are driven by technological advancements rather than viewing the human agent as their starting point. A principled, theoretical approach centered in the individual human agent, their situation and activities that are comprehensive and integrated while at the same time instrumental in the design of ambient ecologies has been lacking. This thesis introduces egocentric interaction as an approach towards the modeling of ambient ecologies with the distinguishing feature of taking the human agent’s body, situation and activities as center of reference, as opposed to the more common device-centric approaches in facilitating human-environment interaction. Egocentric interaction is encapsulated in a number of assumptions and principles such as situatedness, the proximity principle, the physical-virtual equity principle, perception and action instead of “input” and “output,” and activity-centeredness. A situative space model is proposed based on some of these principles. It is intended to capture what a specific human agent can perceive and not perceive, reach and not reach at any given moment in time. The situative space model is for the egocentric interaction paradigm what the virtual desktop is for the WIMP interaction paradigm: more or less everything of interest to a specific human agent is assumed and supposed to happen here. In addition, the conception and implementation of the easy ADL ecology based on egocentric interaction, comprising of smart objects, a personal activity-centric middleware, ambient intelligence applications aimed at everyday activity support, and a human agent literally in the middle of it all is described. The middleware was developed to address important challenges in ambient intelligence: (1) tracking and managing smart objects; (2) tracking a human agent’s situative spaces; (3) recognizing human activities and actions; (4) managing and facilitating human-environment interaction; and (5) to ease up the development of ambient intelligence applications. The easy ADL ecology was first simulated in immersive virtual reality, and then set up physically as a living laboratory to evaluate: (1) the technological and technical performance of individual middleware components, (2) to perform a user experience evaluation assessing various aspects of user satisfaction in relation to the support offered by the easy ADL ecology, and (3) to use it as a research test bed for addressing challenges in ambient intelligence. While it is problematic to directly compare the “proof-of-concept” easy ADL ecology with related research efforts, it is clear from the user experience evaluation that the subjects were positive with the services it offered. / easy ADL project
222

Designing Sociable Technologies

Barraquand, Remi 02 February 2012 (has links) (PDF)
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.
223

Flot de conception dirigé par les modèles pour la commande et la supervision de systèmes domotiques d'assistance

Allègre, Willy 07 December 2012 (has links) (PDF)
En France, comme dans l'ensemble des pays développés, le même constat est dressé : la population vieillit. Cette évolution démographique sans précédent dans l'histoire de l'humanité pose un certain nombre d'enjeux économiques et sociaux liés à la prise en charge des personnes âgées dépendantes et/ou en situation de handicap, dont le nombre augmente considérablement au fil des ans. Le nombre d'aidants potentiels ne pouvant augmenter en conséquence, il faut penser dès aujourd'hui à des solutions alternatives pour permettre à ces personnes de garder un niveau d'autonomie suffisant leur permettant de rester dans leur environnement domestique préféré le plus longtemps possible. Les systèmes domotiques, qui regroupent l'ensemble des technologies de l'informatique, de l'électronique et des télécommunications au sein d'un habitat, permet d'y apporter des solutions technologiques. Dans ces travaux, nous proposons un flot de conception dirigé par les modèles pour la commande et la supervision de systèmes domotiques d'assistance. Dans un premier temps, nous cherchons à intégrer une personne non-experte en domotique (e.g. membre de la famille / aidant, ergothérapeute) dans certaines étapes de la conception pour une meilleure prise en compte des besoins de personnes en situation de handicap mais aussi pour limiter l'intervention relativement coûteuse de l'expert. Pour cela, nous proposons un langage de modélisation (DSML : Domain Specific Modeling Language) permettant de décrire un système domotique en manipulant des concepts à un haut niveau d'abstraction. Ce DSML est composé de deux vues : une vue physique pour représenter l'environnement domotique et une vue fonctionnelle pour définir les interactions entre l'utilisateur et son système domotique. Dans cette dernière vue, deux types d'interactions sont définis pour prendre en compte un nombre de besoins utilisateur le plus grand possible. Ainsi, il est possible de définir des requêtes de différents types (i.e. services) comme des interdictions temporaires (i.e. modes) sur des ressources domotiques. À partir des modèles définis à l'aide de ce langage, notre flot de conception permet de générer la partie commande à l'aide de transformations de modèles successives. Une évaluation sur le cas d'étude des appartements tremplins du centre de Kerpape avec des étudiants puis des ergothérapeutes permet d'avoir des retours intéressants sur l'utilisabilité du DSML et du flot de conception proposé. Dans un deuxième temps, nous cherchons à offrir une solution alternative aux approches de supervision basées sur l'utilisation massive de capteurs, qui peut parfois être problématique lorsque l'on s'intéresse à l'acceptabilité de la solution par l'utilisateur (coût, intrusivité). Nous proposons pour cela d'intégrer dans le flot de conception un modèle de supervision non-intrusif basé sur une ontologie pour représenter les interactions utilisateur-système. Contrairement aux solutions existantes, ce modèle n'est pas basé sur des données de capteurs, mais sur l'analyse sémantique des commandes domotiques envoyées par l'utilisateur. L'ontologie et les règles qui lui sont associées permettent à un moteur d'inférences d'extraire des informations habituellement captées : suivant la manière dont l'utilisateur interagit avec son système domotique, sa localisation et son intention peuvent être déduites par inférences logiques, permettant d'aboutir à la proposition de services contextuels. Une évaluation sur les jeux de données de l'appartement Domus permet de montrer l'intérêt d'une telle approche tant pour limiter l'utilisation de capteurs que pour augmenter la sûreté de fonctionnement par redondance d'informations. Une partie de ces travaux est reprise dans le cadre du projet ASIM porté par l'entreprise Vity Technology. La syntaxe concrète (i.e. représentation graphique) du langage de modélisation sera notamment retravaillé dans un but de commercialisation.
224

Ajouter de l'information spatiale aux modèles de composant logiciel - l'effet de localisation

HASSAN, Ali 25 September 2012 (has links) (PDF)
Highly distributed environments (HDEs) are deployment environments that include powerful and robust machines in addition to resource-constrained and mobile devices such as laptops, personal digital assistants (or PDAs), smart-phones, GPS devices, sensors, etc. Developing software for HDEs is fundamentally different from the software development for central systems and stable distributed systems. This argument is discussed deeply and in-details throughout this dissertation. HDE applications are challenged by two problems: unreliable networks, and heterogeneity of hardware and software. Both challenges need careful handling, where the system must continue functioning and delivering the expected QoS. This dissertation is a direct response to the mentioned challenges of HDEs. The contribution of this dissertation is the cloud component model and its related formal language and tools. This is the general title. However, and to make this contribution clear, we prefer to present it in the following detailed form: (1) We propose a paradigm shift from distribution transparency to localization acknowledgment being the first class concern. (2) To achieve the above mentioned objective, we propose a novel component model called cloud component (CC). (3) In this dissertation we propose a new approach to assemble CCs using systematic methodology that maintains the properties of CC model. (4) Cloud component development process and cloud component based systems development process. (5) Location modeling and advanced localization for HDEs are the pivotal key in our contribution. (6) Formal language to model single CC, CC assembly, CC development process, and CC based systems. (7) We finally present our fully-developed supporting tools: the cloud component management system CCMS, and the Registry utility. To respond to the challenges posed by HDEs, and to maintain expected software quality at the user endpoint, we think we need to pass a ¿paradigm shift¿ from the way software is designed and implemented currently to our new vision that this dissertation is devoted to. This is a paradigm shift from distribution transparency to localization acknowledgment being the first class concern. The contribution in this thesis has several faces as explained above, but still, these faces are cohesive. Each of these faces form a partial contribution, however, this partial contribution does not mean anything if isolated from the overall proposal. Moreover, the merit of the overall proposal can not be grasped by reading one partial contribution. The merit of the proposal is evident only if all parts of this work are cohesively organized. Finally, we claim that our proposal spans the entire software development process for HDEs, from requirements to deployment and runtime management.
225

The Impress Context Store: A Coordination Framework for Context-Aware Systems

Li, Herman Hon Yu January 2006 (has links)
The dream of weaving technology into our everyday fabric of life is recently being made possible by advances in ubiquitous computing and sensor technologies. Countless sensors of various sizes have made their way into everyday commercial applications. Many projects aim to explore new ways to utilize these new technologies to aid and interact with the general population. Context-aware systems use available context information to assist users automatically, without explicit user input. By inferring user intent and configuring the system proactively for each user, context-aware systems are an integral part of achieving user-friendly ubiquitous computing environments. <br /><br /> A common issue with building a distributed context-aware system is the need to develop a supporting infrastructure providing features such as storage, distributed messaging, and security, before the real work on processing context information can be done. This thesis proposes a coordination framework that provides an effective common foundation for context-aware systems. The separation between the context-processing logic component and the underlying supporting foundation allows researchers to focus their energy at the context-processing part of the system, instead of spending their time re-inventing the supporting infrastructure. <br /><br /> As part of an ongoing project, Impress, the framework uses the open standard, Jabber, as its communication protocol. The Publish-Subscribe (pubsub) extension to Jabber provides interesting features that match those needed by a context-aware system. The main contribution of this thesis is the design and implementation of a coordination framework, called the Impress Context Store, that provides an effective common foundation for context-aware systems. The separation between the context-processing logic and the underlying supporting foundation allows researchers to focus their energy at the context-processing part of the system, instead of spending their time re-inventing the supporting infrastructure.
226

The Impress Context Store: A Coordination Framework for Context-Aware Systems

Li, Herman Hon Yu January 2006 (has links)
The dream of weaving technology into our everyday fabric of life is recently being made possible by advances in ubiquitous computing and sensor technologies. Countless sensors of various sizes have made their way into everyday commercial applications. Many projects aim to explore new ways to utilize these new technologies to aid and interact with the general population. Context-aware systems use available context information to assist users automatically, without explicit user input. By inferring user intent and configuring the system proactively for each user, context-aware systems are an integral part of achieving user-friendly ubiquitous computing environments. <br /><br /> A common issue with building a distributed context-aware system is the need to develop a supporting infrastructure providing features such as storage, distributed messaging, and security, before the real work on processing context information can be done. This thesis proposes a coordination framework that provides an effective common foundation for context-aware systems. The separation between the context-processing logic component and the underlying supporting foundation allows researchers to focus their energy at the context-processing part of the system, instead of spending their time re-inventing the supporting infrastructure. <br /><br /> As part of an ongoing project, Impress, the framework uses the open standard, Jabber, as its communication protocol. The Publish-Subscribe (pubsub) extension to Jabber provides interesting features that match those needed by a context-aware system. The main contribution of this thesis is the design and implementation of a coordination framework, called the Impress Context Store, that provides an effective common foundation for context-aware systems. The separation between the context-processing logic and the underlying supporting foundation allows researchers to focus their energy at the context-processing part of the system, instead of spending their time re-inventing the supporting infrastructure.
227

The Impact of Shared and Personal Devices on Collaborative Process and Performance

Wallace, James Richard January 2012 (has links)
On a daily basis humans interact with an increasing variety of personal electronic devices, ranging from laptops, tablets, smartphones, and e-readers to shared devices such as projected displays and interactive, digital tabletops. An emerging area of study focuses on understanding how these devices can be used together to support collaborative work. Where prior research has shown benefits of devices used individually, there is currently a lack of understanding of how devices should be used in conjunction to optimize a group's performance. In particular, the research presented in this dissertation combines qualitative and quantitative analyses of group work in three empirical studies to link the use of shared and personal devices to changes in group performance and process. In the first study, participants performed an optimization task with either a single, shared projected display or with the shared, projected display and personal laptops. Analyses of study data indicated that when personal displays were present, group performance was improved for the optimization task ($p = 0.025$). However, personal devices also reduced a group's ability to coordinate ($p = 0.016$). Additionally, when personal devices were present, individuals primarily used those devices instead of dividing time between their laptops and the shared display. To further investigate the support that shared displays provide groups, and in particular, how shared displays might support group work in multi-display settings, a follow-up study was conducted. The second study investigated how two different types of shared displays supported group work. In particular, shared workspaces, which allowed multiple users to simultaneously interact with shared content, and status displays, which provided awareness of the overall problem state to groups, were investigated. While no significant impact on group performance was observed between the two shared display types, qualitative analysis of groups working in these conditions provided insight into how the displays supported collaborative activities. Shared workspace displays provided a visual reference that aided individuals in grounding communication with their collaborators. On the other hand, status displays enabled the monitoring of a group's overall task progress. Regardless of which display was present, an individual's gaze and body position relative to the shared display supported the synchronization of group activities. Finally, where the previous two studies identified collaborative activities that were supported by the use of shared and personal displays, the experimental task performed by participants did not explore the transfer of task materials between shared and personal devices or alternative personal and shared devices. The third study addressed these limitations through the adoption of a new experimental task that enabled the exploration of how the manipulation of task artefacts supported collaborative activities, and alternative shared and personal devices in the form of interactive digital tabletops and tablet computers. In particular, the third study compared how personal and shared displays supported sensemaking groups working under three conditions: with shared, digital tables, with shared digital tables plus personal tablets, and with only personal tablets. Quantitative analyses revealed that the presence of the shared, digital tabletop significantly improved a group's ability to perform the sensemaking task ($p = 0.019$). Further, qualitative analyses revealed that the table supported key sensemaking activities: the prioritization of task materials, the ability to compare data, and the formation of group hypotheses. This dissertation makes four primary contributions to the field of Computer Supported Cooperative Work. First, it identifies cases where the presence of shared and personal displays provide performance benefits to groups, and through qualitative analyses links these performance benefits to group processes. Second, observed uses are grounded in an established process model, and used to identify collaborative activities that are supported by personal and shared devices. Third, equity of participation on shared displays is found to positively correlate ($p = 0.028$), and equity of participation on personal displays is found to negatively correlate ($p = 0.01$) with group performance for sensemaking tasks. Fourth, the method for studying group process and performance based on teamwork and taskwork provides a useful foundation for future studies of collaborative work.
228

Programming Idioms and Runtime Mechanisms for Distributed Pervasive Computing

Adhikari, Sameer 13 October 2004 (has links)
The emergence of pervasive computing power and networking infrastructure is enabling new applications. Still, many milestones need to be reached before pervasive computing becomes an integral part of our lives. An important missing piece is the middleware that allows developers to easily create interesting pervasive computing applications. This dissertation explores the middleware needs of distributed pervasive applications. The main contributions of this thesis are the design, implementation, and evaluation of two systems: D-Stampede and Crest. D-Stampede allows pervasive applications to access live stream data from multiple sources using time as an index. Crest allows applications to organize historical events, and to reason about them using time, location, and identity. Together they meet the important needs of pervasive computing applications. D-Stampede supports a computational model called the thread-channel graph. The threads map to computing devices ranging from small to high-end processing elements. Channels serve as the conduits among the threads, specifically tuned to handle time-sequenced streaming data. D-Stampede allows the dynamic creation of threads and channels, and for the dynamic establishment (and removal) of the plumbing among them. The Crest system assumes a universe that consists of participation servers and event stores, supporting a set of applications. Each application consists of distributed software entities working together. The participation server helps the application entities to discover each other for interaction purposes. Application entities can generate events, store them at an event store, and correlate events. The entities can communicate with one another directly, or indirectly through the event store. We have qualitatively and quantitatively evaluated D-Stampede and Crest. The qualitative aspect refers to the ease of programming afforded by our programming abstractions for pervasive applications. The quantitative aspect measures the cost of the API calls, and the performance of an application pipeline that uses the systems.
229

Provably Secure Privacy Mechanism for Authentication, Billing and Payment in Mobile Communications

Shi-Ming, Vincent 23 August 2010 (has links)
Mobile communication is very mature today due to the powerful computation and communication capabilities of mobile devices, the flourishing of mobile networks, the popularity of electronic commerce, and the completeness of e-payment mechanisms. It is a pleasure for mobile users to roam around the mobile networks and enjoy the mobile network services. However, there are a lot of security threats in the mobile networks, and thus we need an anonymous mutual authentication and key exchange scheme to guarantee the security and privacy for mobile users in the networks. A payment protocol is also required for charging the mobile users after using the mobile services. However, the existing payment schemes do not support anonymity and credit-based chargeability at the same time. In this dissertation, we propose a secure authentication scheme such that the mobile users can be anonymously authenticated by the system and the system can still make correct charge to these anonymous mobile users via a credit-based way simultaneously. We also propose a novel e-cash scheme which can support each mobile user to withdraw a generic e-cash and decide to spend it as an on-line e-cash or an off-line e-cash according to the payment requirement of the anonymous authentication scheme. Our proposed schemes are convenient and flexible for the mobile users, the system operator, and the bank. Besides, full privacy can be achieved for mobile users owing to the combination of our proposed schemes, which can be performed in current mobile devices efficiently with few battery energy consumptions. Furthermore, we provide anonymity control, no swindling, tamper resistance, secure mutual authentication, secure key exchange, and secure forward secrecy in the proposed anonymous authentication scheme and the e-cash scheme, where these security features are demonstrated by formal security models and theoretical proofs.
230

A Novel User Activity Prediction Model For Context Aware Computing Systems

Peker, Serhat 01 September 2011 (has links) (PDF)
In the last decade, with the extensive use of mobile electronic and wireless communication devices, there is a growing need for context aware applications and many pervasive computing applications have become integral parts of our daily lives. Context aware recommender systems are one of the popular ones in this area. Such systems surround the users and integrate with the environment / hence, they are aware of the users&#039 / context and use that information to deliver personalized recommendations about everyday tasks. In this manner, predicting user&rsquo / s next activity preferences with high accuracy improves the personalized service quality of context aware recommender systems and naturally provides user satisfaction. Predicting activities of people is useful and the studies on this issue in ubiquitous environment are considerably insufficient. Thus, this thesis proposes an activity prediction model to forecast a user&rsquo / s next activity preference using past preferences of the user in certain contexts and current contexts of user in ubiquitous environment. The proposed model presents a new approach for activity prediction by taking advantage of ontology. A prototype application is implemented to demonstrate the applicability of this proposed model and the obtained outputs of a sample case on this application revealed that the proposed model can reasonably predict the next activities of the users.

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