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Publication Computer graphics techniques for modeling page turning(Working Paper, University of Waikato, Department of Computer Science, 2007-10-24) Liesaputra, Veronica; Witten, Ian H.Turning the page is a mechanical part of the cognitive act of reading that we do literally unthinkingly. Interest in realistic book models for digital libraries and other online documents is growing. Yet actually producing a computer graphics implementation for modeling page turning is a challenging undertaking. There are many possible foundations: two-dimensional models that use reflection and rotation; geometrical models using cylinders or cones; mass-spring models that simulate the mechanical properties of paper at varying degrees of fidelity; finite-element models that directly compute the actual forces within a piece of paper. Even the simplest methods are not trivial, and the more sophisticated ones involve detailed physical and mathematical models. The variety, intricacy and complexity of possible ways of simulating this fundamental act of reading is virtually unknown. This paper surveys computer graphics models for page turning. It combines a tutorial introduction that covers the range of possibilities and complexities with a mathematical synopsis of each model in sufficient detail to serve as a basis for implementation. Illustrations are included that are generated by our implementations of each model. The techniques presented include geometric methods (both two- and three-dimensional), mass-spring models with varying degrees of accuracy and complexity, and finite-element models. We include a detailed comparison of experimentally-determined computation time and subjective visual fidelity for all methods discussed. The simpler techniques support convincing real-time implementations on ordinary workstations.Publication A map-based place-browser for a PDA(Working Paper, University of Waikato, 2007-10-24) Bainbridge, David; Jones, Matt; Arter, DavidThis article describes PlaceBrowser, a PDA based application that allows the user of the application to navigate around an area of geographical interest, such as a city, using a zoomable, panable hierarchy of aerial images, in a fashion similar to Google Maps. The novel aspect to the work is that an area of precise interest within the map can be pin-pointed by the user by directly dragging out a rectangular area on the map. This forms the source to a spatial search that returns landmarks that are then used to trigger a Web based query. The results of this query are displayed to the user. The net effect is that, in response to dragging out a rectangular area, web pages that are relevant to this area but have not been explicitly geo-spatially tagged with metadata (longitude,latitude) are shown to the user.Publication Digital libraries on an iPod: Beyond the client-server model(Working Paper, University of Waikato, Department of Computer Science, 2007-10-24) Bainbridge, David; Jones, Steve; McIntosh, Samuel John; Jones, MattThis paper describes an experimental system that enhanced an iPod with digital library capabilities. Using the open source digital library software Greenstone as a base, this paper more specifically maps out the technical steps necessary to achieve this, along with an account of our subsequent experimentation. This included command-line usage of Greenstone's basic runtime system on the device, augmenting the iPod’s main interactive menu-driven application to include searching and hierarchical browsing of digital library collections stored locally, and a selection of "launcher" applications for target documents such as text files, images and audio. Media rich applications for digital stories and collaging were also developed. We also configured the iPod to run as a web server to provide digital library content to others over a network, effectively turning the traditional mobile client-server upsidedown.Publication Extracting corpus specific knowledge bases from Wikipedia(Working Paper, University of Waikato, Department of Computer Science, 2007-06-01) Milne, David N.; Witten, Ian H.; Nichols, David M.Thesauri are useful knowledge structures for assisting information retrieval. Yet their production is labor-intensive, and few domains have comprehensive thesauri that cover domain-specific concepts and contemporary usage. One approach, which has been attempted without much success for decades, is to seek statistical natural language processing algorithms that work on free text. Instead, we propose to replace costly professional indexers with thousands of dedicated amateur volunteers--namely, those that are producing Wikipedia. This vast, open encyclopedia represents a rich tapestry of topics and semantics and a huge investment of human effort and judgment. We show how this can be directly exploited to provide WikiSauri: manually-defined yet inexpensive thesaurus structures that are specifically tailored to expose the topics, terminology and semantics of individual document collections. We also offer concrete evidence of the effectiveness of WikiSauri for assisting information retrieval.Publication Sharing, privacy and trust issues for photo collections(Working Paper, University of Waikato, 2007-02-01) Adams, Anne; Cunningham, Sally Jo; Masoodian, MasoodDigital libraries are quickly being adopted by the masses. Technological developments now allow community groups, clubs, and even ordinary individuals to create their own, publicly accessible collections. However, users may not be fully aware of the potential privacy implications of submitting their documents to a digital library, and may hold misconceptions of the technological support for preserving their privacy. We present results from 18 autoethnographic investigations and 19 observations / interviews into privacy issues that arise when people make their personal photo collections available online. The Adams' privacy model is used to discuss the findings according to information receiver, information sensitivity, and information usage. Further issues of trust and ad hoc poorly supported protection strategies are presented. Ultimately while photographic data is potentially highly sensitive, the privacy risks are often hidden and the protection mechanisms are limited.Publication Initiating and Sustaining Female Networks in Computer Science and IT(Working Paper, University of Waikato, Department of Computer Science, 2007-08-01) Oelinger, Maria; Hinze, AnnikaOver the last decade, several networks and communities for women in IT have been initiated. It has been known that specific needs for support exist where members of a minority have difficulties in finding like-minded people in their everyday environment. This paper investigates different forms of female networks in Computer Science and IT. In particular, it analyses forms of network initiation, which often involve face-to-face meetings at regular events like conferences or, increasingly, at summer universities for female students. We conducted three studies to identify the attendees' expectations and needs for support using questionnaires, interviews, and a wiki analysis. This paper aims at identifying effective strategies for initiating female networks.Publication Flexible refinement(Working Paper, University of Waikato, 2007-05-07) Reeves, Steve; Streader, DavidTo help make refinement more usable in practice we introduce a general, flexible model of refinement. This is defined in terms of what contexts an entity can appear in, and what observations can be made of it in those contexts. Our general model is expressed in terms of an operational semantics, and by exploiting the well-known isomorphism between state-based relational semantics and event-based labelled transition semantics we were able to take particular models from both the state- and event-based literature, reflect on them and gradually evolve our general model. We are also able to view our general model both as a testing semantics and as a logical theory with refinement as implication. Our general model can used as a bridge between different particular special models and using this bridge we compare the definition of determinism found in different special models. We do this because the reduction of nondeterminism underpins many definitions of refinement found in a variety of special models. To our surprise we find that the definition of determinism commonly used in the process algebra literature to be at odds with determinism as defined in other special models. In order to rectify this situation we return to the intuitions expressed by Milner in CCS and by formalising these intuitions we are able to define determinism in process algebra in such a way that it no longer at odds with the definitions we have taken from other special models. Using our abstract definition of determinism we are able to construct a new model, interactive branching programs, that is an implementable subset of process algebra. Later in the chapter we show explicitly how five special models, taken from the literature, are instances of our general model. This is done simply by fixing the sets of contexts and observations involved. Next we define vertical refinement on our general model. Vertical refinement can be seen both as a generalisation of what, in the literature, has been called action refinement or non-atomic refinement. Alternatively, by viewing a layer as a logical theory, vertical refinement is a theory morphism, formalised as a Galois connection. By constructing a vertical refinement between broadcast processes and interactive branching programs we can see how interactive branching programs can be implemented on a platform providing broadcast communication. But we have been unable to extend this theory morphism to implement all of process algebra using broadcast communication. Upon investigation we show the problem arises with the examples that caused the problem with the definition of determinism on process algebra. Finally we illustrate the usefulness of our flexible general model by formally developing a single entity that contains events that use handshake communication and events that use broadcast communication.Publication Location-based indexing for mobile context-aware access to a digital library(Working Paper, University of Waikato, 2007-08-22) Hinze, Annika; Osborn, WendyMobile information systems need to collaborate with each other to provide seamless information access to the user. Information about the user and their context provides the points of contact between the systems. Location is the most basic user context. TIP is a mobile tourist information system that provides location-based access to documents in the digital library Greenstone. This paper identifies the challenges for providing effcient access to location-based information using the various access modes a tourist requires on their travels. We discuss our extended 2DR-tree approach to meet these challenges.