Este trabalho apresenta uma proposta de infra-estrutura de software sensível ao contexto para a computação ubíqua (ubicomp) denominada Continuum. A área de ubicomp, também chamada de computação pervasiva, pressupõe uma forte integração com o mundo real, com foco no usuário e na manutenção de alta transparência. Para o desenvolvimento de aplicativos nesse cenário, é necessária uma infra-estrutura de software adequada. A infra-estrutura projetada é baseada no padrão da arquitetura orientada a serviços (service-oriented architecture ou SOA), fazendo uso de framework e middleware, e empregando uma redefinição da semântica siga-me. Nessa visão redefinida, os usuários podem ir para qualquer lugar carregando os dados e os aplicativos que desejam, os quais podem ser usados de forma imperceptível e integrada com o mundo real (seamless integration). O foco particular desse trabalho é sensibilidade ao contexto: a percepção de características relacionadas aos usuários e ao entorno. No trabalho são considerados os recursos disponíveis no ambiente e é mantida a história dos dados de contexto. Além disso, é proposta a representação do contexto para promover raciocínio e compartilhamento de conhecimento, empregando uma ontologia. Dessa forma, contexto é representado de uma maneira formal e bastante expressiva, diferente de muitas soluções existentes hoje em dia que ainda usam modelos de representação ad hoc. Esta tese está então na interseção destas três áreas principais: infra-estrutura de software para ubicomp, sensibilidade ao contexto e ontologias. No desenvolvimento desta tese, também examina-se o campo da computação ubíqua, e sugere-se um modelo de arquitetura geral que enfrente esses desafios fundamentais. Baseado nos requisitos estabelecidos para esse modelo, propõe-se um conjunto de serviços para o Continuum. Os serviços são projetados considerando o trabalho previamente desenvolvido pelo nosso grupo de pesquisa, mais especificamente o projeto ISAM, e particularmente o middleware EXEHDA. A proposta estende esses projetos, adicionando aspectos que não haviam sido considerados no momento do seu desenvolvimento. Particularmente, o suporte a sensibilidade de contexto é melhorado com a proposta de uma ontologia para a formalização da informação de contexto. Algumas análises, usando a metodologia de estudo de caso, foram conduzidas para apreciar as principais proposições da tese. Baseado nessas avaliações, foram apresentadas algumas lições aprendidas e traçada a conclusão do trabalho. Como resultado, Continuum é uma infra-estrutura de software que endereça muitos aspectos da computação ubíqua, integrando imperceptivelmente diferentes desafios. / The present work is a proposal of a context-aware software infrastructure for ubiquitous computing (ubicomp) named Continuum. The ubicomp area, also called pervasive computing, presupposes a strong integration with the real world, with focus on the user and on keeping high transparency. For the development of applications in this scenario, we need an adequate software infrastructure. The infrastructure designed in this work is based on service-oriented architecture (SOA), making use of framework and middleware, and employing a redefinition of follow-me semantics. In this redefined vision, users can go anywhere carrying the data and application they want, which they can use in a seamlessly integrated fashion with the real world. The specific focus of our work is context awareness: the perception of characteristics related to users and surroundings. We consider the resources available in the environment and keep a history of context data. Furthermore, we propose the representation of context to promote reasoning and knowledge sharing, using ontology. In this way, context is represented in a considerably expressive, formal approach, different from many solutions that exist today, which still use ad hoc representations models. Our work is then at the intersection of these three main areas: software infrastructures for ubicomp, context awareness, and ontologies. In the development of this thesis, we also survey the field of ubiquitous computing, suggesting a general architectural model to deal with its fundamental challenges. Based on the established requirements for this model, we propose a set of services for Continuum. The services are designed considering the previous works developed by our research group, namely ISAM (Infra-estrutura de Suporte às Aplicações Móveis – Mobile Applications Support Infrastructure), and particularly the middleware EXEHDA (Execution Environment for Highly Distributed Applications). We further extend these projects, by adding aspects to them that had not been considered at the time of their development. Particularly, we improve context awareness support, proposing an ontology for the formalization of context information. We have conducted some analysis, using case study methodology, to evaluate the main propositions of our work. Based on these assessments, we present lessons learned and draw the conclusion of our work. As a result, Continuum is a software infrastructure that addresses many aspects of ubiquitous computing, seamlessly integrating many different challenges.

Abstract This single, embedded case study focused on educators’ experiences of educational change as they adopted, implemented, and sustained a one-to-one computing innovation over 20 years. The purpose of the study was to explore the innovativeness, the capacity of a school community to take on change for continuous educational improvement over time. Through interviews and focus groups with administrators, teachers, students, and graduates, observations of current classroom practices, and archival data, the study provides an understanding of how individuals experienced change and how a school sustained change over an exceptionally long period of time. Data analysis revealed multiple rationales for the implementation of one-to-one computing, including the development of a constructivist environment, the empowerment of women, preparation of students for college and the 21st century work force, and the need to keep the school’s educational program on the “cutting-edge.” The study of this individual school community suggests the importance of a strong educational philosophy, flexibility of implementation, an environment that encourages risk-taking, and collegiality. The study also demonstrates that change occurred on a continuum and continued to progress as hardware, software, and the Internet evolved, and as faculty became more knowledgeable of the application of the program to teaching and learning.

[pt] A computação ubíqua aliada ao avanço tecnológico de sensores definiu um novo cenário no qual a integração de diversos recursos computacionais pode contribuir para que um conjunto de serviços e funcionalidades esteja disponível ao usuário sempre que necessário. Um subconjunto desta área é de sistemas sensíveis às atividades realizadas por seus usuários, isto é, sistemas que utilizam informações sobre o que o usuário está fazendo. Nesses sistemas, mecanismos de inferência são essenciais para reconhecer ações do usuário e permitir que o comportamento do sistema se adapte a estas ações. Entretanto, como esses ambientes são caracterizados por uma elevada troca de informações, o desenvolvimento deste tipo de sistema não é uma tarefa trivial e possui como desafios: privacidade, desempenho, complexidade e ambigüidade das informações coletadas. O objetivo deste trabalho é propor uma arquitetura para sistemas de inferências de atividades do usuário. Para atingir esse objetivo, definimos um conjunto de componentes que representam funções especificas do processo de inferência. Com o objetivo de analisar a viabilidade da arquitetura proposta, desenvolvemos, avaliamos e relatamos um protótipo de sistema baseado na arquitetura. / [en] The ubiquitous computing combined with the advance of sensor technology creates a scenario in which the integration of several computing resources is used to keep a set of services and features available to the user whenever necessary. A particular trend in this area is the activity based systems, i.e., systems that are aware of the activity played by the user. In these systems, inference engine is essential to recognize user’s actions and allow the systems to adapt its behavior according to user’s actions. Though, the development of this type of systems is not a trivial task as the high rate of information exchanged brings challenges related to privacy, performance and information management. In this work we propose an architecture for activity inference systems. To achieve this goal, we define a set of components that perform important roles in the inference process. Finally, to show the feasibility of this approach, we designed, implemented and evaluated a system based on the proposed architecture.

Ubiquitous computing aims to make human-computer interaction as naturalistic and functionally invisible as possible through embedding computing potential within a particular context to support human activity. However, much of ubiquitous computing research is focussed on technical innovation due to the challenges involved with deploying embedded computing, thereby reducing the commitment to the philosophical ideals of ubiquitous computing in research. This dissertation describes the investigation of a participatory approach to technically-complex research in order to understand how our view of the engineering and human challenges changes when the two are approached hand-in-hand. The domain chosen for this system was a dental surgery. Dentistry involves a complex workspace with computer interaction constrained by surgery hygiene. Ubiquitous computing offers a compelling interaction alternative to the keyboard and mouse paradigm in such an environment. A multi-method approach that employed ethnographic research and design prototyping was undertaken with dentists from several different private practices. A series of field studies used ethnographic methods such as observation and interview. Design events explored prototypes with activities such as design games, contextual interviews, role-playing and contextual prototyping. Activities were devised with the aim of providing a level playing field, whereby both designers and participants feel they can contribute equally, with their respective disciplinary knowledge. It was found that methods needed to be carefully chosen, devised and managed, in order to communicate complex concepts with participants and to constrain the design to technically feasible options. The thesis examines the design problem from the perspectives of a variety of different stakeholders within a participatory design framework, reflected upon by means of human-centred action research. Data was gathered through design speculations and observation, and explored using methods such as the Video Card Game and Video Interaction Analysis. Fieldwork was analysed using a multi-stage qualitative analysis process which informed further design collaboration with participants. The analysis of data gathered during design studies with dentists also contributed to the development of a prototype system to validate methodological contributions. The resulting prototype utilised off-the-shelf hardware and software which allowed for innovative customisation and development. In-situ prototyping (defined by the author as “participatory bootstrapping”) and a comprehensive knowledge of the domain afforded the creative application of technology. In addition to contributing to the prototype design, the interpretive understandings drawn from analysis identified how technical ideas were presented and utilised by participants of the studies, and how best to engage busy professionals. The final outcomes of the research were a multimodal ubiquitous computing system for interacting within a dental surgery; the development and implementation of a variety of methods aimed at communicating technical concepts and eliciting user motivations, practices and concerns; and a set of design principles for engineers engaging in design of systems for human use. The research presented within this thesis is primarily part of the field of human-computer interaction, but provides evidence of how engineering development can be influenced by a user-centred participatory approach. The benefits that derive from inclusive methods of design are demonstrated by the evaluation of a prototype that employed such methods. The contribution of this thesis is to demonstrate and delineate methods for developing ubiquitous computing technologies for the context of human use. This led to a set of design principles for the engineering of systems for human use: 1. Technology needs to be robust and simple to appropriate. This allows users to give insights on technology developments and also to allow users to discover for themselves how they would use the technology. 2. An evolving and carefully considered set of methods are needed to elicit communication between practitioners and across disciplines. The gaps in understandings and the different representations that arise across the disciplines provide essential clues to next steps in design. These gaps and differences form tensions that can be exploited productively. 3. Context is important for determining which design steps to take. Rather than abstracting a problem in order to solve it, as is usual in engineering design, the problem should remain grounded in the context of use. It reveals what the real problems are that need to be solved rather than the imagined ones. This requires an appreciation of the situated nature of action and of the variability of work. In turn it also requires an appreciation of what the human can and does do and what the machine should support. 4. Accountability in design is required. There is a fundamental tension between trying to make something work and seeing what really does work; specifically it is necessary to understand when automation is worth it in human machine systems. While engaged in the design process, engineers should ask how much technology should reconfigure human practices because of a useful outcome, rather than attempting to automate and converge devices for its own sake. A clear understanding of the constraints and workings of the work space needs to be balanced with the understandings of the limitations of the technology in order to design a system that improves work practice and empowers the practitioner.

<p>Military work-practice is a difficult area of research where paper-based approaches are still extended. This thesis proposes a solution which permits the digitalization of information at the same time as workpractice remains unaltered for soldiers working with maps in the field. For this purpose, a mobile interactive paper-based platform has been developed which permits the users to maintain their current work-flow. The premise of the solution parts from a system consisting of a prepared paper-map, a cellular phone, a desktop computer, and a digital pen with bluetooth connection. The underlying idea is to permit soldiers to take advantage of the information a computerized system can offer, at the same time as the overhead it incurs is minimized. On one hand this implies that the solution must be light-weight, on the other it must retain current working procedures as far as possible. The desktop computer is used to develop new paper-driven applications through the application provided in the development framework, thus allowing the tailoring of applications to the changing needs of military operations. One major component in the application suite is a symbol recognizer which is capable of recognizing symbols parting from a template which can be created in one of the applications. This component permits the digitalization of information in the battlefield by drawing on the paper-map. The proposed solution has been found to be viable, but still there is a need for further development. Furthermore, there is a need to adapt the existing hardware to the requirements of the military to make it usable in a real-world situation.</p>

This thesis contributes with insights into how aspects of the surrounding physical and social context can be exploited in the design of mobile media applications for playful use. In this work, context refers to aspects of the immediate surroundings – outside of the device – that can be identified and measured by sensors; for instance environmental aspects like sound, and social aspects like co-located people. Two extensive case studies explore the interplay between users, mobile media, and aspects of context in different ways, and how it can invite playful use. The first case study, Context Photography, uses sensor-based information about the immediate physical surroundings to affect images in real time in a novel digital camera application for everyday creativity. The second, Push!Music, makes it possible to share music both manually and autonomously between co-located people, based on so-called media context, for spontaneous music sharing. The insights gained from the designs, prototypes, and user studies, point at the value of combining explicit and implicit interaction – essentially, the expected and unexpected – to open for playful use. The explicit interaction encouraged users to be active, exploratory, and creative. The implicit interaction let users embrace and exploit dynamic qualities of the surroundings, contributing to making the systems fun, exciting, magical, ‘live’, and real. This combination was facilitated through our approach to context, where sensor-based information was mostly open in use and interpretation, ambiguous, visible, and possible to override for users, and through giving the systems a degree of agency and autonomy. A key insight is that the combination of explicit and implicit interaction allowed both control and a sense of magic in the interaction with the mobile media applications, which together seems to encourage play and playfulness.

With the increasing pervasiveness of mobile technologies such as cellular phones, personal digital assistants and hand held computers, mobile technologies promise the next major technological and cultural shift. Like the Internet, it is predicted that the greatest impact will not come from hardware devices or software programs, but from emerging social practices, which were not possible before. To capitalize on the benefits of mobile technologies, organizations have begun to implement nomadic computing environments. Nomadic computing environments make available the systems support needed to provide computing and communication capabilities and services to the mobile work force as they move from place to place in a manner that is transparent, integrated, convenient and adaptive. Already, anecdotes suggest that within organizations there are social implications occurring with both unintended and intended consequences being perpetuated. The problems of nomadic computing users have widely been described in terms of the challenges presented by the interplay of time, space and context, yet a theory has yet to be developed which analyzes this interplay in a single effort. A temporal human agency perspective proposes that stakeholders’ actions are influenced by their ability to recall the past, respond to the present and imagine the future. By extending the temporal human agency perspective through the recognition of the combined influence of space and context on human action, I investigated how the individual practices of eleven nomadic computing users changed after implementation. Under the umbrella of the interpretive paradigm, and using a cross case methodology this research develops a theoretical account of how several stakeholders engaged with different nomadic computing environments and explores the context of their effectiveness. Applying a literal and theoretical replication strategy to multiple longitudinal and retrospective cases, six months were spent in the field interviewing and observing participants. Data analysis included three types of coding: descriptive, interpretive and pattern coding. The findings reveal that patterns of technology use in nomadic computing environments are influenced by stakeholders’ temporal orientations; their ability to remember the past, imagine the future and respond to the present. As stakeholders all have different temporal orientations and experiences, they exhibit different practices even when engaging initially with the same organizational and technical environments. Opposing forces emerge as users attempt to be effective by resolving the benefits and disadvantages of the environment as they undergo different temporal, contextual and spatial experiences. Insights about the ability to predict future use suggest that because they are difficult to envisage in advance, social processes inhibit the predictability of what technologies users will adopt. The framework presented highlights the need to focus on understanding the diversity in nomadic computing use practices by examining how they are influenced by individual circumstances as well as shared meanings across individuals.

L'informatique pervasive (ou ubiquitaire) est un support pour des environnements contenant de nombreux objets (ou dispositifs) disséminés, équipés d'électronique et interconnectés. Ces dispositifs fournissent un accès distant à une multitude de fonctionnalités qui nous aident dans notre vie quotidienne. Les Architectures Orientées Services sont adaptées à la conception de logiciels pervasifs. En e ffet, chaque dispositif fournit son propre ensemble de fonctionnalités sous la forme de services. Ainsi, en l'absence de mécanisme complémentaire, les utilisateurs se trouvent limités à utiliser les services isolément alors que leurs besoins correspondent à des scénarios qui impliquent une composition de multiples services o erts par plusieurs appareils. Dans cette thèse, nous défendons qu'un système pervasif doit : d'une part, permettre aux utilisateurs d'exprimer facilement leurs besoins en créant des scénarios et d'autre part, proposer à ses utilisateurs une représentation et des moyens de gestion de leur contexte afin qu'ils puissent tirer le meilleur parti de leur environnement et de ses changements. De plus, la présence de plusieurs utilisateurs implique la nécessité de collaborer. Par ailleurs, l'exécution de scénarios doit être résiliente aux changements environnementaux et aux actions des utilisateurs. Elle doit ainsi s'adapter dynamiquement et, si possible, tirer profit du contexte et des changements de l'environnement. Notre contribution, nommée SaS (Scenarios as Services), répond à ces objectifs. Elle propose une approche interopérable capable de s'adapter à l'environnement. Elle fournit une représentation persistante et personnalisable du contexte et inclut un langage de description de scénarios destiné aux utilisateurs. Ces scénarios sont facilement contrôlables, personnalisables et réutilisables. Elle planifie l'exécution pas à pas des scénarios, afin de s'adapter aux changements de l'environnement et de bénéficier des avantages de la mobilité des utilisateurs (exécution d'un scénario, dans la durée, sur plusieurs lieux). Enfin, elle inclut le partage de scénarios qui permet aux utilisateurs de collaborer. Un prototype de SaS, basé sur des normes industrielles (telle qu'OSGi), prouve la faisabilité de notre contribution et nous permet de l'évaluer sur un cas d'étude simple.

Interactions in the style of the ubiquitous computing paradigm are possible today, but only in handcrafted environments within one administrative and technological realm. This thesis describes an architecture (called Continuum), a design that realises the architecture, and a proof-of-concept implementation that brings ubiquitous computing to chaotic environments. Essentially, Continuum enables an ecology at the edge of the network, between users, competing service providers from overlapping administrative domains, competing internet service providers, content providers, and software developers that want to add value to the user experience. Continuum makes the ubiquitous computing functionality orthogonal to other application logic. Existing web applications are augmented for ubiquitous computing with functionality that is dynamically compiled and injected by a middleware proxy into the web pages requested by a web browser at the user?s mobile device. This enables adaptability to environment variability, manageability without user involvement, and expansibility without changes to the mobile. The middleware manipulates self-contained software units with precise functionality (called <i>frames</i>), which help the user interact with contextual services in conjunction with the data to which they are attached. The middleware and frame design explicitly incorporates the possibility of discrepancies between the assumptions of ubiquitous-computing software developers and field realities: multiple administrative domains, unavailable service, unavailable software, and missing contextual information. A framework for discovery and authorisation addresses the chaos inherent to the paradigm through the notion of <i>role assertions</i> acquired dynamically by the user. Each assertion represents service access credentials and contains bootstrapping points for service discovery on behalf of the holding user. A proof-of-concept prototype validates the design, and implements several frames that demonstrate general functionality, including driving discovery queries over multiple service discovery protocols and making equivalences between service types, across discovery protocols.

Interactions in the style of the ubiquitous computing paradigm are possible today, but only in handcrafted environments within one administrative and technological realm. This thesis describes an architecture (called Continuum), a design that realises the architecture, and a proof-of-concept implementation that brings ubiquitous computing to chaotic environments. Essentially, Continuum enables an ecology at the edge of the network, between users, competing service providers from overlapping administrative domains, competing internet service providers, content providers, and software developers that want to add value to the user experience. Continuum makes the ubiquitous computing functionality orthogonal to other application logic. Existing web applications are augmented for ubiquitous computing with functionality that is dynamically compiled and injected by a middleware proxy into the web pages requested by a web browser at the user?s mobile device. This enables adaptability to environment variability, manageability without user involvement, and expansibility without changes to the mobile. The middleware manipulates self-contained software units with precise functionality (called <i>frames</i>), which help the user interact with contextual services in conjunction with the data to which they are attached. The middleware and frame design explicitly incorporates the possibility of discrepancies between the assumptions of ubiquitous-computing software developers and field realities: multiple administrative domains, unavailable service, unavailable software, and missing contextual information. A framework for discovery and authorisation addresses the chaos inherent to the paradigm through the notion of <i>role assertions</i> acquired dynamically by the user. Each assertion represents service access credentials and contains bootstrapping points for service discovery on behalf of the holding user. A proof-of-concept prototype validates the design, and implements several frames that demonstrate general functionality, including driving discovery queries over multiple service discovery protocols and making equivalences between service types, across discovery protocols.