Quality of experience aware adaptive hypermedia system

The research reported in this thesis proposes, designs and tests a novel Quality of Experience Layer (QoE-layer) for the classic Adaptive Hypermedia Systems (AHS) architecture. Its goal is to improve the end-user perceived Quality of Service in different operational environments suitable for residential users. While the AHS’ main role of delivering personalised content is not altered, its functionality and performance is improved and thus the user satisfaction with the service provided. The QoE Layer takes into account multiple factors that affect Quality of Experience (QoE), such as Web components and network connection. It uses a novel Perceived Performance Model that takes into consideration a variety of performance metrics, in order to learn about the Web user operational environment characteristics, about changes in network connection and the consequences of these changes on the user’s quality of experience. This model also considers the user’s subjective opinion about his/her QoE, increasing its effectiveness and suggests strategies for tailoring Web content in order to improve QoE. The user related information is modelled using a stereotype-based technique that makes use of probability and distribution theory. The QoE-Layer has been assessed through both simulations and qualitative evaluation in the educational area (mainly distance learning), when users interact with the system in a low bit rate operational environment. The simulations have assessed “learning” and “adaptability” behaviour of the proposed layer in different and variable home connections when a learning task is performed. The correctness of Perceived Performance Model (PPM) suggestions, access time of the learning process and quantity of transmitted data were analysed. The results show that the QoE layer significantly improves the performance in terms of the access time of the learning process with a reduction in the quantity of data sent by using image compression and/or elimination. A visual quality assessment confirmed that this image quality reduction does not significantly affect the viewers’ perceived quality that was close to “good” perceptual level. For qualitative evaluation the QoE layer has been deployed on the open-source AHA! system. The goal of this evaluation was to compare the learning outcome, system usability and user satisfaction when AHA! and QoE-ware AHA systems were used. The assessment was performed in terms of learner achievement, learning performance and usability assessment. The results indicate that QoE-aware AHA system did not affect the learning outcome (the students have similar-learning achievements) but the learning performance was improved in terms of study time. Most significantly, QoE-aware AHA provides an important improvement in system usability as indicated by users’ opinion about their satisfaction related to QoE

Research reports: 1990 NASA/ASEE Summer Faculty Fellowship Program

Reports on the research projects performed under the NASA/ASEE Summer Faculty Fellowship Program are presented. The program was conducted by The University of Alabama and MSFC during the period from June 4, 1990 through August 10, 1990. Some of the topics covered include: (1) Space Shuttles; (2) Space Station Freedom; (3) information systems; (4) materials and processes; (4) Space Shuttle main engine; (5) aerospace sciences; (6) mathematical models; (7) mission operations; (8) systems analysis and integration; (9) systems control; (10) structures and dynamics; (11) aerospace safety; and (12) remote sensin

Semantic technologies: from niche to the mainstream of Web 3? A comprehensive framework for web Information modelling and semantic annotation

Context: Web information technologies developed and applied in the last decade have considerably changed the way web applications operate and have revolutionised information management and knowledge discovery. Social technologies, user-generated classification schemes and formal semantics have a far-reaching sphere of influence. They promote collective intelligence, support interoperability, enhance sustainability and instigate innovation. Contribution: The research carried out and consequent publications follow the various paradigms of semantic technologies, assess each approach, evaluate its efficiency, identify the challenges involved and propose a comprehensive framework for web information modelling and semantic annotation, which is the thesis’ original contribution to knowledge. The proposed framework assists web information modelling, facilitates semantic annotation and information retrieval, enables system interoperability and enhances information quality. Implications: Semantic technologies coupled with social media and end-user involvement can instigate innovative influence with wide organisational implications that can benefit a considerable range of industries. The scalable and sustainable business models of social computing and the collective intelligence of organisational social media can be resourcefully paired with internal research and knowledge from interoperable information repositories, back-end databases and legacy systems. Semantified information assets can free human resources so that they can be used to better serve business development, support innovation and increase productivity

MediaSync: Handbook on Multimedia Synchronization

This book provides an approachable overview of the most recent advances in the fascinating field of media synchronization (mediasync), gathering contributions from the most representative and influential experts. Understanding the challenges of this field in the current multi-sensory, multi-device, and multi-protocol world is not an easy task. The book revisits the foundations of mediasync, including theoretical frameworks and models, highlights ongoing research efforts, like hybrid broadband broadcast (HBB) delivery and users' perception modeling (i.e., Quality of Experience or QoE), and paves the way for the future (e.g., towards the deployment of multi-sensory and ultra-realistic experiences). Although many advances around mediasync have been devised and deployed, this area of research is getting renewed attention to overcome remaining challenges in the next-generation (heterogeneous and ubiquitous) media ecosystem. Given the significant advances in this research area, its current relevance and the multiple disciplines it involves, the availability of a reference book on mediasync becomes necessary. This book fills the gap in this context. In particular, it addresses key aspects and reviews the most relevant contributions within the mediasync research space, from different perspectives. Mediasync: Handbook on Multimedia Synchronization is the perfect companion for scholars and practitioners that want to acquire strong knowledge about this research area, and also approach the challenges behind ensuring the best mediated experiences, by providing the adequate synchronization between the media elements that constitute these experiences

Dynamic Interaction and Manipulation of Web Resources

In this thesis we join methods for evaluating queries over interlinked resources via link traversal with approaches for the integration of data over interlinked schemata via reasoning. Our approach allows for the on-the-fly alignment and processing of dynamically retrieved data in a streaming fashion including incremental query answering. We go beyond the simple consumption of exposed information by enabling manipulations of remote resources in a parallel execution system

HIPPO -- an adaptive open hyptertext system

The hypertext paradigm offers a powerful way of modelling complex knowledge structures. Information can be arranged into networks, and connected using hypertext links. This has led to the development of more open hypertext design, which allow hypertext services to be integrated seamlessly into the user's environment. Recent research has also seen the emergence of adaptive hypertext, which uses feedback from the user to modify objects in the hypertext. The research presented in this thesis describes the HIPPO hypertext model which combines many of the ideas in open hypertext research, with existing work on adaptive hypertext systems. The idea of fuzzy anchors are introduced which allow authors to express the uncertainty and vagueness which is inherent in a hypertext anchor. Fuzzy anchors use partial truth values which allow authors to define a "degree of membership" for anchors. Anchors no longer have fixed, discrete boundaries, but have more in common with contour lines used in map design. These fuzzy anchors are used as the basis for an adaptive model, so that anchors can be modified in response to user actions. The HIPPO linking model introduces linkbase trees which combine link collections into inheritance hierarchies. These are used to construct reusable inheritance trees, which allow authors to reuse and build on existing link collections. An adaptive model is also presented to modify these linkbase hierarchies. Finally, the HIPPO system is re-implemented using a widely distributed architecture. This distributed model implements a hypertext system as a collection of lightweight, distributed services. The benefits of this distributed hypertext model are discussed, and an adaptive model is then suggested

Semantic discovery and reuse of business process patterns

Patterns currently play an important role in modern information systems (IS) development and their use has mainly been restricted to the design and implementation phases of the development lifecycle. Given the increasing significance of business modelling in IS development, patterns have the potential of providing a viable solution for promoting reusability of recurrent generalized models in the very early stages of development. As a statement of research-in-progress this paper focuses on business process patterns and proposes an initial methodological framework for the discovery and reuse of business process patterns within the IS development lifecycle. The framework borrows ideas from the domain engineering literature and proposes the use of semantics to drive both the discovery of patterns as well as their reuse

HIPPO -- an adaptive open hyptertext system

The hypertext paradigm offers a powerful way of modelling complex knowledge structures. Information can be arranged into networks, and connected using hypertext links. This has led to the development of more open hypertext design, which allow hypertext services to be integrated seamlessly into the user's environment. Recent research has also seen the emergence of adaptive hypertext, which uses feedback from the user to modify objects in the hypertext. The research presented in this thesis describes the HIPPO hypertext model which combines many of the ideas in open hypertext research, with existing work on adaptive hypertext systems. The idea of fuzzy anchors are introduced which allow authors to express the uncertainty and vagueness which is inherent in a hypertext anchor. Fuzzy anchors use partial truth values which allow authors to define a "degree of membership" for anchors. Anchors no longer have fixed, discrete boundaries, but have more in common with contour lines used in map design. These fuzzy anchors are used as the basis for an adaptive model, so that anchors can be modified in response to user actions. The HIPPO linking model introduces linkbase trees which combine link collections into inheritance hierarchies. These are used to construct reusable inheritance trees, which allow authors to reuse and build on existing link collections. An adaptive model is also presented to modify these linkbase hierarchies. Finally, the HIPPO system is re-implemented using a widely distributed architecture. This distributed model implements a hypertext system as a collection of lightweight, distributed services. The benefits of this distributed hypertext model are discussed, and an adaptive model is then suggested

A documentation paradigm for an integrated software maintenance support environment

Recent advances in computer hardware have not been matched by comparable advances in computer software, inhibiting the production of reliable software at greater levels of productivity. Development of software is restricted by the so-called "maintenance backlog". Productivity in the maintenance sector has not kept pace with increasing annual labour costs, making the maintenance of software the major item in the budget, of organisations responsible for the development and maintenance of software. Gains in productivity can be anticipated by the exploitation of software-maintenance tools, within the framework of an Integrated .Software Maintenance Support Environment (ISMSE). for which a high-level design has been proposed in this thesis, offering comprehensive support for all phases of the software life-cycle, particularly the maintenance phase. A key factor in the reliable modification of software is the time taken to gain the prerequisite understanding, by a study of the system's documentation. This documentation degrades over a period of time, becoming unreliable, inhibiting maintenance of the software, which may be a large capital asset, ultimately, the software may become impossible to maintain, requiring replacement. Understanding gained during maintenance is wide-ranging and at various levels of abstraction, but is often NOT well-recorded, since no effective documentation system exists for recording the maintenance history of large software systems. The documentation paradigm in this thesis, used within the framework of an ISMSE, aims to provide a means of recording the knowledge gained during maintenance, facilitating easier future maintenance, and preserving the reliability of the documentation, so reducing the time required to gain an understanding of the software being maintained. This provides a powerful means of increasing productivity, while simultaneously preserving a valuable capital asset