• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 198
  • 137
  • 33
  • 19
  • 17
  • 10
  • 4
  • 4
  • 3
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 470
  • 470
  • 162
  • 125
  • 111
  • 108
  • 91
  • 86
  • 77
  • 69
  • 67
  • 67
  • 63
  • 60
  • 59
  • 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.
191

Ubiquitous Computing: By the People, For the People

Ndiwalana, Ali 21 August 2003 (has links)
Computing is moving away from the desktop, permeating into many everyday objects and the environments in which we live. Many researchers in ubiquitous computing are excited about the potential to profoundly change the way we live by revolutionizing how we interact with information. Despite the excitement, few successful applications are making the transition from the laboratories to the mass market. While this could easily be attributed to the immaturity of the research area, it is also a manifestation of a larger problem—the lack of coherent methods, processes or tools that assist designers in thinking about issues pertinent to ubiquitous computing, as they explore potential ideas and develop some of these into working prototypes. To this end, this research presents an overview of the important characteristics of ubiquitous computing systems identified by many of the leading researchers in the field. Contrasting with conventional systems, we discuss the resulting issues and challenges, and their implications on the future directions of this emerging research area. In a case study, we use scenario-based design to walkthrough the design of a community computing application. At various stages of the design process, the need to focus on more issues relevant to ubiquitous computing design became apparent, resulting in the augmentation of scenario-based design. The augmented scenario-based design process is proposed as a tool for helping designers conceptualize user activities within given usage circumstances and at various stages of the design process. New questions help to identify the most common pitfalls, enabling designers to produce systems that are more socially acceptable and provide a higher likelihood for adoption by everyday users beyond the laboratory. In initial testing, the augmented process was shown to produce better designs. The ultimate ambition of ubiquitous computing technology is to be able to serve users anywhere, at anytime. However, taking into account the dynamic nature of user needs and usage situations, is a novel and non trivial undertaking. In essence, it is a fundamental change that requires designers to rethink many of the conventional answers and processes that help guide the creation of interactive systems. We provide a promising approach. / Master of Science
192

Semantic interoperability in ad-hoc computing environments

Rendo Fernandez, Jose Ignacio January 2007 (has links)
This thesis introduces a novel approach in which multiple heterogeneous devices collaborate to provide useful applications in an ad-hoc network. This thesis proposes a smart home as a particular ubiquitous computing scenario considering all the requirements given by the literature for succeed in this kind of systems. To that end, we envision a horizontally integrated smart home built up from independent components that provide services. These components are described with enough syntactic, semantic and pragmatic knowledge to accomplish spontaneous collaboration. The objective of these collaboration is domestic use, that is, the provision of valuable services for home residents capable of supporting users in their daily activities. Moreover, for the system to be attractive for potential customers, it should offer high levels of trust and reliability, all of them not at an excessive price. To achieve this goal, this thesis proposes to study the synergies available when an ontological description of home device functionality is paired with a formal method. We propose an ad-hoc home network in which components are home devices modelled as processes represented as semantic services by means of the Web Service Ontology (OWL-S). In addition, such services are specified, verified and implemented by means of the Communicating Sequential Processes (CSP), a process algebra for describing concurrent systems. The utilisation of an ontology brings the desired levels of knowledge for a system to compose services in a ad-hoc environment. Services are composed by a goal based system in order to satisfy user needs. Such system is capable of understaning, both service representations and user context information. Furthermore, the inclusion of a formal method contributes with additional semantics to check that such compositions will be correctly implemented and executed, achieving the levels of reliability and costs reduction (costs derived form the design, development and implementation of the system) needed for a smart home to succeed.
193

Dynamische Verwaltung heterogener Kontextquellen in global verteilten Systemen

Hamann, Thomas 30 January 2009 (has links) (PDF)
Im Rahmen der Dissertation wurde ein Middlewaredienst entwickelt und realisiert. Es gestattet die dynamische Verwaltung heterogener Kontextquellen. Das zugrunde liegende Komponentenmodell selbstbeschreibender Context Provieder ermöglicht die lose Kopplung von Kontextquellen und -senken. Es wird durch Filter- und Konverterkomponenten zur generischen Providersselektion anhand domänenspezifischer Merkmale ergänzt. Die Kopplung der verteilten Dienstinstanzen erfolgt durch ein hybrides Peer-to-Peer-System. Dies trägt der Heterogenität der Endgeräte Rechnung, und erlaubt die skalierbare , verteilte Verwaltung von Kontextquellen in globalen Szenarien.
194

Dynamische Verwaltung heterogener Kontextquellen in global verteilten Systemen

Hamann, Thomas 05 December 2008 (has links)
Im Rahmen der Dissertation wurde ein Middlewaredienst entwickelt und realisiert. Es gestattet die dynamische Verwaltung heterogener Kontextquellen. Das zugrunde liegende Komponentenmodell selbstbeschreibender Context Provieder ermöglicht die lose Kopplung von Kontextquellen und -senken. Es wird durch Filter- und Konverterkomponenten zur generischen Providersselektion anhand domänenspezifischer Merkmale ergänzt. Die Kopplung der verteilten Dienstinstanzen erfolgt durch ein hybrides Peer-to-Peer-System. Dies trägt der Heterogenität der Endgeräte Rechnung, und erlaubt die skalierbare , verteilte Verwaltung von Kontextquellen in globalen Szenarien.
195

Context-aware gestural interaction in the smart environments of the ubiquitous computing era

Caon, Maurizio January 2014 (has links)
Technology is becoming pervasive and the current interfaces are not adequate for the interaction with the smart environments of the ubiquitous computing era. Recently, researchers have started to address this issue introducing the concept of natural user interface, which is mainly based on gestural interactions. Many issues are still open in this emerging domain and, in particular, there is a lack of common guidelines for coherent implementation of gestural interfaces. This research investigates gestural interactions between humans and smart environments. It proposes a novel framework for the high-level organization of the context information. The framework is conceived to provide the support for a novel approach using functional gestures to reduce the gesture ambiguity and the number of gestures in taxonomies and improve the usability. In order to validate this framework, a proof-of-concept has been developed. A prototype has been developed by implementing a novel method for the view-invariant recognition of deictic and dynamic gestures. Tests have been conducted to assess the gesture recognition accuracy and the usability of the interfaces developed following the proposed framework. The results show that the method provides optimal gesture recognition from very different view-points whilst the usability tests have yielded high scores. Further investigation on the context information has been performed tackling the problem of user status. It is intended as human activity and a technique based on an innovative application of electromyography is proposed. The tests show that the proposed technique has achieved good activity recognition accuracy. The context is treated also as system status. In ubiquitous computing, the system can adopt different paradigms: wearable, environmental and pervasive. A novel paradigm, called synergistic paradigm, is presented combining the advantages of the wearable and environmental paradigms. Moreover, it augments the interaction possibilities of the user and ensures better gesture recognition accuracy than with the other paradigms.
196

Leveraging contextual cues for dynamic scene understanding

Bettadapura, Vinay Kumar 27 May 2016 (has links)
Environments with people are complex, with many activities and events that need to be represented and explained. The goal of scene understanding is to either determine what objects and people are doing in such complex and dynamic environments, or to know the overall happenings, such as the highlights of the scene. The context within which the activities and events unfold provides key insights that cannot be derived by studying the activities and events alone. \emph{In this thesis, we show that this rich contextual information can be successfully leveraged, along with the video data, to support dynamic scene understanding}. We categorize and study four different types of contextual cues: (1) spatio-temporal context, (2) egocentric context, (3) geographic context, and (4) environmental context, and show that they improve dynamic scene understanding tasks across several different application domains. We start by presenting data-driven techniques to enrich spatio-temporal context by augmenting Bag-of-Words models with temporal, local and global causality information and show that this improves activity recognition, anomaly detection and scene assessment from videos. Next, we leverage the egocentric context derived from sensor data captured from first-person point-of-view devices to perform field-of-view localization in order to understand the user's focus of attention. We demonstrate single and multi-user field-of-view localization in both indoor and outdoor environments with applications in augmented reality, event understanding and studying social interactions. Next, we look at how geographic context can be leveraged to make challenging ``in-the-wild" object recognition tasks more tractable using the problem of food recognition in restaurants as a case-study. Finally, we study the environmental context obtained from dynamic scenes such as sporting events, which take place in responsive environments such as stadiums and gymnasiums, and show that it can be successfully used to address the challenging task of automatically generating basketball highlights. We perform comprehensive user-studies on 25 full-length NCAA games and demonstrate the effectiveness of environmental context in producing highlights that are comparable to the highlights produced by ESPN.
197

Canevas de programmation pour gérer l'héterogénéité et la consommation d'énergie des mobiles dans un environnement ubiquitaire

Guan, Hongyu 01 June 2012 (has links) (PDF)
L'hétérogénéité des objets communicants et la consommation d'énergie sont deux considérations fondamentales pour les environnements informatiques ubiquitaires. Dans cette thèse, nous présentons notre approche pour gérer l'hétérogénéité et pour économiser l'énergie via des canevas de programmation dédiés. Pour gérer l'hétérogénéité, nous proposons une méthodologie et un support de programmation qui visent à faire communiquer les différents objets communicants de l'environnement ubiquitaire, et ce, en utilisant le protocole SIP considéré alors comme un bus de communication universel. Nous avons intégré ce bus SIP dans les canevas de programmation générés à partir des descriptions d'applications d'informatique ubiquitaire, écrites dans le langage DiaSpec. Concernant la consommation d'énergie, nous proposons une méthodologie qui utilise les techniques d'offloading et de compression de données pour minimiser la consommation d'énergie des applications mobiles. Nous avons ainsi construit une stratégie d'aide à la conception au travers d'un outil qui permet de déterminer le meilleur mode d'exécution pour une tâche donnée. Nous proposons l'intégration de cette stratégie dans le langage de description DiaSpec.
198

Context Awareness & Pervasive Computing: Arquitectura lógica de un sistema perceptivo al contexto de un usuario

Barrientos, Alfredo, Calderón, Julissa E., Mujica, Stephanie 07 1900 (has links)
Los Sistemas Perceptivos del Contexto son capaces de reconocer y anticipar proactivamente a necesidades próximas del usuario teniendo en cuenta intereses, ubicación y proximidad, incluso sin necesidad de comunicárselo de manera explícita. Esto gracias al aprovechamiento de las redes sociales como la herramienta de “Inteligencia de Negocios” que permitirá no sólo conectar a los consumidores con las marcas sino también para entender a los clientes finales y con ello desarrollar productos y servicios especializados. Context Awareness se apoya de los Sistemas de Posicionamiento Global (GSP) quienes facilitan servicios basados en la ubicación del usuario para la creación de soluciones contextuales. Diversas arquitecturas son propuestas para el desarrollo de soluciones contextuales sin embargo carecen de ubicuidad, lo que limita la aplicabilidad de las mismas. Este estudio propone una arquitectura lógica para un Sistema Perceptivo del Contexto que permita agilizar la fase de desarrollo reflejando los niveles de dependencia entre componentes hardware y software. A modo validación se proponen escenarios aplicativos que consumen los servicios y dominios propuestos en la arquitectura con ayuda del procesamiento de los sensores y dispositivos inteligentes del mercado móvil. De esta manera, el estudio mejora el desarrollo de los Sistemas Inteligentes. / Los Sistemas Perceptivos del Contexto son capaces de reconocer y anticipar proactivamente a necesidades próximas del usuario teniendo en cuenta intereses, ubicación y proximidad, incluso sin necesidad de comunicárselo de manera explícita. Esto gracias al aprovechamiento de las redes sociales como la herramienta de “Inteligencia de Negocios” que permitirá no sólo conectar a los consumidores con las marcas sino también para entender a los clientes finales y con ello desarrollar productos y servicios especializados. Context Awareness se apoya de los Sistemas de Posicionamiento Global (GSP) quienes facilitan servicios basados en la ubicación del usuario para la creación de soluciones contextuales. Diversas arquitecturas son propuestas para el desarrollo de soluciones contextuales sin embargo carecen de ubicuidad, lo que limita la aplicabilidad de las mismas. Este estudio propone una arquitectura lógica para un Sistema Perceptivo del Contexto que permita agilizar la fase de desarrollo reflejando los niveles de dependencia entre componentes hardware y software. A modo validación se proponen escenarios aplicativos que consumen los servicios y dominios propuestos en la arquitectura con ayuda del procesamiento de los sensores y dispositivos inteligentes del mercado móvil. De esta manera, el estudio mejora el desarrollo de los Sistemas Inteligentes.
199

Vers la sécurisation des systèmes d'informatique ubiquitaire par le design : une approche langage / Towards securing pervasive computing systems by design : a language approach

Jakob, Henner 27 June 2011 (has links)
Dans de multiples domaines, un nombre grandissant d'applications interagissant avec des entités communicantes apparaissent dans l'environnement pour faciliter les activités quotidiennes~(domotique et télémédecine). Leur impact sur la vie de tous les jours des utilisateurs rend ces applications critiques: leur défaillance peut mettre en danger des personnes et leurs biens. Bien que l'impact de ces défaillances puisse être majeur, la sécurité est souvent considérée comme un problème secondaire dans le processus de développement et est traitée par des approches ad hoc.Cette thèse propose d'intégrer des aspects de sécurité dans le cycle de développement des systèmes d'informatique ubiquitaire. La sécurité est spécifiée à la conception grâce à des déclarations dédiées et de haut niveau. Ces déclarations sont utilisées pour générer un support de programmation afin de faciliter l'implémentation des mécanismes de sécurité, tout en séparant ces aspects de sécurité de la logique applicative. Notre approche se concentre sur le contrôle d'accès aux entités et la protection de la vie privée. Notre travail a été implémenté et fait levier sur une suite outillée existante couvrant le cycle de développement logiciel. / A growing number of environments is being populated with a range of networked devices. Applications leverage these devices to support everyday activities in a variety of areas (e.g., home automation and patient monitoring). As these devices and applications get woven into our everyday activities, they become critical: their failure can put people and assets at risk. Failures can be caused by malicious attacks and misbehaving applications. Although the impact of such situations can be major, security concerns are often considered a secondary issue in the development process, and treated with ad hoc approaches. This thesis proposes to address security concerns throughout the development lifecycle of a pervasive computing system. Security is addressed at design time thanks to dedicated, high-level declarations. These declarations are processed to implement security mechanisms, and to generate programming support to ease the development of the security logic, while keeping it separate from the application logic. Our approach is studied in the context of access control and privacy concerns. Our work has been implemented and leverages an existing software-design language and a suite of tools that covers the software development lifecycle.
200

Predictive Modeling for Persuasive Ambient Technology

Powell, Jason W. 08 1900 (has links)
Computer scientists are increasingly aware of the power of ubiquitous computing systems that can display information in and about the user's environment. One sub category of ubiquitous computing is persuasive ambient information systems that involve an informative display transitioning between the periphery and center of attention. The goal of this ambient technology is to produce a behavior change, implying that a display must be informative, unobtrusive, and persuasive. While a significant body of research exists on ambient technology, previous research has not fully explored the different measures to identify behavior change, evaluation techniques for linking design characteristics to visual effectiveness, nor the use of short-term goals to affect long-term behavior change. This study uses the unique context of noise-induced hearing loss (NIHL) among collegiate musicians to explore these issues through developing the MIHL Reduction Feedback System that collects real-time data, translates it into visuals for music classrooms, provides predictive outcomes for goalsetting persuasion, and provides statistical measures of behavior change.

Page generated in 0.034 seconds