UWSpace

UWSpace is the University of Waterloo’s institutional repository for the free, secure, and long-term home of research produced by faculty, students, and staff.

Depositing Theses/Dissertations or Research to UWSpace

Are you a Graduate Student depositing your thesis to UWSpace? See our Thesis Deposit Help and UWSpace Thesis FAQ pages to learn more.

Are you a Faculty or Staff member depositing research to UWSpace? See our Waterloo Research Deposit Help and Self-Archiving pages to learn more.

Photo by Waterloo staff

Communities in UWSpace

Select a community to browse its collections.

Recent Submissions

  • Thumbnail Image
    Item type: Item ,
    An end-user domain specific model to drive dynamic user agents adaptations
    (University of Waterloo, 2010-03-03) Nunes, Ingrid Oliveira de; Barbosa, Simone Diniz Junqueira; Lucena, Carlos Jose Pereira de
    Modelling automated user tasks based on agent-oriented approaches is a promising but challenging task. Personalized user agents have been investigated as a potential way of addressing this issue. Most of recent research work has focused on learning, eliciting and reasoning about user preferences and profiles. In this paper, our goal is to deal with the engineering of such systems, barely discussed in the literature. In this context, we present a high-level domain specific model whose aim is to give users the power of customizing and dynamically adapting their user agents. In addition, we propose a general architecture to develop agent-based systems able to be customized to users.
  • Thumbnail Image
    Item type: Item ,
    Incorporating trust in network visualization
    (University of Waterloo, 2010-03-04) Mekouar, Loubna; Iraqi, Youssef; Boutaba, Raouf
    In this paper, we propose a trust management framework for network virtualization environments. The proposed framework helps distinguish among the infrastructure providers based on their past experiences and feedbacks from service providers. We describe the main components involved in gathering the feedbacks and managing the reputation data. We detail the proposed trust system and define the concept of degree of involvement of an infrastructure provider in terms of nodes and links. We also perform a mathematical analysis of the proposed system. Simulation results confirm the effectiveness of the proposed trust management system in increasing the service providers' satisfaction and reducing the selection of infrastructure providers that do not fulfill their Service Level Agreement (SLA).
  • Thumbnail Image
    Item type: Item ,
    Understanding the effects and implications of gesture-based interaction for dynamic presentations
    (University of Waterloo, 2010-02-11) Fourney, Adam; Terry, Michael; Mann, Richard
    Gesture-based interaction has long been seen as a natural means of input for electronic presentation systems. However, gesture-based presentation systems have not been evaluated in real-world contexts. This paper presents the design and evaluation of Maestro, a gesture-based presentation system whose design was informed by observations of real world practices. To understand the implications of gesture-based interaction, Maestro was deployed in a classroom setting for two weeks. The study results indicate that gestures that support interaction with content are valued most, as opposed to those that support slide navigation. Notably, past systems have only used gestures for slide navigation. Our study also revealed that the presenter would position, orient, and conduct himself in ways to more reliably perform gestures and perceive system feedback, and to avoid accidental gesture recognition. However, these behaviors negatively impacted presentation dynamics. Collectively, these results outline clear directions for future research.
  • Thumbnail Image
    Item type: Item ,
    Distributed XML query processing: Fragmentation, localization and pruning
    (University of Waterloo, 2010-09-14) Kling, Patrick; Ozsu, M. Tamer; Daudjee, Khuzaima
    Distributing data collections by fragmenting them is an effective way of improving the scalability of a database system. While the distribution of relational data is well understood, the unique characteristics of XML data and its query model present challenges that require different distribution techniques. In this paper, we show how XML data can be fragmented horizontally and vertically. Based on this, we propose solutions to two of the problems encountered in distributed query processing and optimization on XML data, namely localization and pruning. Localization takes a fragmentation-unaware query plan and converts it to a distributed query plan that can executed at the sites that hold XML data fragments in a distributed system. We then show how the resulting distributed query plan can be pruned so that only those sites are accessed that can contribute to the query result. We demonstrate that our techniques can be integrated into a real-life XML database system and that they significantly improve the performance of distributed query execution.
  • Thumbnail Image
    Item type: Item ,
    Points-to analysis with efficient strong updates
    (University of Waterloo, 2010-02-01) Lhotak, Ondrej; Chung, Kwok-Chiang Andrew
    This paper explores a sweet spot between flow-insensitive and flow-sensitive subset-based points-to analysis. Flow-insensitive analysis is efficient: it has been applied to million-line programs and its worst-case requirements are quadratic space and cubic time. Flow-sensitive analysis is precise because it allows strong updates so that points-to relationships holding on one program location can be removed from the analysis when they no longer hold in other locations. We propose a "Strong Update" analysis combining both features: it is efficient like flow-insensitive analysis, with the same worst-case bounds, yet its precision benefits from strong updates like flow-sensitive analysis. The key enabling insight is that strong updates are applicable when the dereferenced points-to set is a singleton, and a singleton set is cheap to analyze. The analysis therefore focuses flow sensitivity on singleton sets. Larger sets, which will not lead to strong updates, are modelled flow insensitively to maintain efficiency. We have implemented and evaluated the analysis as an extension of the standard flow-insensitive points-to analysis in the LLVM compiler infrastructure.