Thesis (M. Journ.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 36-45).

Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003. / Includes bibliographical references (leaves 170-181). Also available in electronic version. Access restricted to campus users.

The combination of traditional process migration and the new virtualization technology enables mobility of virtual machines and resource provisioning within data centers. While applied to wide area network (WAN), a traditional migration algorithm has to adjust itself according to the various WAN situations and VM status. This thesis identifies four performance measurements of a VM migration: total migration time, downtime, remote up time and performance degradation. It observes that the total migration time and the remote up time of traditional pre-copy over WAN is too long to tolerate. This thesis claims that even for WAN, post-copy could be used to improve the total migration time and remote up time, only by introducing tolerable, predictable and controllable performance degradation. The adaptiveness of the migration algorithm is concerned. It proposes a hybrid solution of pre-copy and post-copy, both for memory and storage, to do the migration. In the hybrid solution, a fraction of memory (Mfrac) and a fraction of storage (Sfrac) are migrated in the pre-copy and freeze-and-copy phase, and the remaining are migrated in the post-copy phase. A model-based solution with the help of profiling is proposed to adaptively find the best combination of Mfrac and Sfrac. The evaluation part suggests that the proposed solution could adapt to different application behaviors and network conditions. / published_or_final_version / Computer Science / Master / Master of Philosophy

Not available / text

published_or_final_version / Linguistics / Master / Master of Arts in Applied Linguistics

Champions of social classification praise its flexible and collaborative nature, in contrast to the rigidity and authoritarianism that they see in traditional classificative structures (such as Kroski, 2005; Shirky, 2005c; Merholz, 2004). In the view of these writers, social classification applications such as the photo storage Web site Flickr and the Web bookmarks manager del.icio.us are both democratic, incorporating the participation of all Web users, and emergent, changing rapidly in response to new content. On the other hand, traditional methods for organizing information, particularly those that involve hierarchy, are seen as exclusive, because they may not represent all usersâ viewpoints, and imprecise, because they cannot be easily adapted for the rapid pace of content development engendered by Web publishing. Two claims appear to underlie these descriptions of social classification. One, that the goal of classification is to identify and locate items based on a personal sense of appropriate categorization, and two, that, if enough other users index (or tag) items according to their own personal ideas of appropriate categorization, then all possibilities will be represented, and both searching and browsing will be facilitated. This paper will evaluate these claims, particularly in regards to the role and nature of authority in organizational schemes, and the intersection of authority with an organizational schemeâ s purpose. I consider these issues for three services often associated with social classification systems: * Indexing of personal collections. * Sharing of indexed personal collections. * Merging of personal collections into a group-indexed aggregate collection. The bookmarks manager del.icio.us is the primary example of a social classification system used throughout this paper.

The interactive society is characterized by a desire for participation that involves, on the one hand, citizens, workers and customers and on the other, politicians, decision makers and entrepreneurs â irrespective of whether this occurs in the public or the private sectors. Another way of explaining the interactive society can be found in the concept of 2.0. Libraries must relate to web 2.0 in the same way they related to web 1.0. The key is to identify the possibilities that the new techniques offer.

This position paper argues that the Web 2.0 phenomenon is an important object of study for information systems research, and that a social informatics approach to understanding Web 2.0 is particularly relevant and useful. We discuss Wikipedia as an example of empirical research on Web 2.0 that can help bridge the divide between academic and popular discourse on new technology movements.

This item is not the definitive copy. Please use the following citation when referencing this material: Dillon, A. (2000) Designing a better learning environment with the Web: problems and prospects. CyberPsychology and Behavior, 3(1), 97-102. Abstract: In a recent review of the empirical findings on hypermedia and learning outcomes, Dillon and Gabbard (1998) concluded that contrary to many people's assumptions, the use of hypermedia-based instructional systems in education had not produced significant learning gains. Indeed, their review concluded that such instructional technologies rarely showed any benefit for learners over existing paper- or lecture-based instructions. While it is commonplace these days to dismiss as irrelevant any media comparison study, the Dillon and Gabbard review went further, also examining comparisons made between alternative hypermedia implementations (a within-media comparison) and between single and group learners employing this technology. Since hypermedia is the underlying technology of the World Wide Web, their findings made depressing reading for those of us who believe that this technology is important and could be put to powerful instructional use. The present issue contains papers from many leading theorists who advocate the use and exploitation of information technologies such as hypermedia and the World-Wide Web in our classrooms, and I am not completely in disagreement with them. However, I wish to question the very assumptions on which the use of the Web and standalone hypermedia applications are based. What I aim to provide in this paper is a sense of the gaps in our knowledge, and to speculate on why education is so poorly served by the wonderful technologies that are within our grasp.

This is a preprint of an article published in the Journal of Information Science Vol. 32, No. 2, 131-148 (2006). This study measures the frequency in which search engines update their indices. Therefore, 38 websites that are updated on a daily basis were analysed within a time-span of six weeks. The analysed search engines were Google, Yahoo and MSN. We find that Google performs best overall with the most pages updated on a daily basis, but only MSN is able to update all pages within a time-span of less than 20 days. Both other engines have outliers that are quite older. In terms of indexing patterns, we find different approaches at the different engines: While MSN shows clear update patterns, Google shows some outliers and the update process of the Yahoo index seems to be quite chaotic. Implications are that the quality of different search engine indices varies and not only one engine should be used when searching for current content.