534 research outputs found

    Reconciling Versioning and Context in Hypermedia Structure Servers

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    Contextual structure servers and versioning servers share a similar goal in allowing different views on a stored structure according to the viewer’s perspective. In this paper we argue that a generic contextual model can be used to facilitate versioning. In order to prove our hypothesis we have drawn on our experiences with OHP-Version to extend FOHM’s contextual model

    Exact Tests via Complete Enumeration: A Distributed Computing Approach

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    The analysis of categorical data often leads to the analysis of a contingency table. For large samples, asymptotic approximations are sufficient when calculating p-values, but for small samples the tests can be unreliable. In these situations an exact test should be considered. This bases the test on the exact distribution of the test statistic. Sampling techniques can be used to estimate the distribution. Alternatively, the distribution can be found by complete enumeration. A new algorithm is developed that enables a model to be defined by a model matrix, and all tables that satisfy the model are found. This provides a more efficient enumeration mechanism for complex models and extends the range of models that can be tested. The technique can lead to large calculations and a distributed version of the algorithm is developed that enables a number of machines to work efficiently on the same problem

    On Hyperstructure and Musical Structure

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    In this paper we report on an ongoing investigation into the relationship between musical structure and hyperstructure, based on a series of open hypermedia systems research projects that have featured case studies involving musical content. We provide a general overview of the intersection between hypermedia and musical structure, drawing also on ideas from narrative structure. Through the example systems we consider techniques for building hyperstructure from musical structure and, conversely, building musical structure from hyperstructure. Additionally we describe an experiment in the sonification of hyperstructure

    DEEP: a provenance-aware executable document system

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    The concept of executable documents is attracting growing interest from both academics and publishers since it is a promising technology for the dissemination of scientific results. Provenance is a kind of metadata that provides a rich description of the derivation history of data products starting from their original sources. It has been used in many different e-Science domains and has shown great potential in enabling reproducibility of scientific results. However, while both executable documents and provenance are aimed at enhancing the dissemination of scientific results, little has been done to explore the integration of both techniques. In this paper, we introduce the design and development of DEEP, an executable document environment that generates scientific results dynamically and interactively, and also records the provenance for these results in the document. In this system, provenance is exposed to users via an interface that provides them with an alternative way of navigating the executable document. In addition, we make use of the provenance to offer a document rollback facility to users and help to manage the system's dynamic resources

    Observations on Pervasive Information Systems Design

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    This paper seeks to lay out a number of observations on Pervasive information systems design that have been made during the Chawton House project, an augmented field trip for school children. After laying out the Chawton House case study, the information infrastructure is described and arising issues are examined concerning design for persistence, empowerment of non technical users, and re-use

    Navigational Hypertext Models For Physical Hypermedia Environments

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    In this paper we identify a common aim between ubiquitous computing and hypertext systems: the desire to present navigable, located and structured information. We propose that existing navigational hypertext models might be valuable as a formalisation of ubiquitous information and explore the challenges of applying standard hypertext operations, such as anchor resolution, display and link traversal, to links that have physical anchors

    The Pipeline of Enrichment: Supporting Link Creation for Continuous Media

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    The application of open hypermedia to temporal media has previously been explored with respect to the link service, in particular link delivery and generic linking. This paper is based on the notion of continuous metadata, in which we use metadata in a temporally significant manner to capture and convey the information required to support linking. With a focus on link creation and live processing, our approach enriches hypermedia content with additional metadata at a number of points between capture and delivery. We illustrate this approach with a tool which assists metadata capture by annotation of continuous media according to a simple ontology

    Binding of hydrogen on benzene, coronene, and graphene from quantum Monte Carlo calculations

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    Quantum Monte Carlo calculations with the diffusion Monte Carlo (DMC) method have been used to compute the binding energy curves of hydrogen on benzene, coronene, and graphene. The DMC results on benzene agree with both Moller-Plessett second order perturbation theory (MP2) and coupled cluster with singles, doubles, and perturbative triples [CCSD(T)] calculations, giving an adsorption energy of similar to 25 meV. For coronene, DMC agrees well with MP2, giving an adsorption energy of similar to 40 meV. For physisorbed hydrogen on graphene, DMC predicts a very small adsorption energy of only 5 +/- 5 meV. Density functional theory (DFT) calculations with various exchange-correlation functionals, including van der Waals corrected functionals, predict a wide range of binding energies on all three systems. The present DMC results are a step toward filling the gap in accurate benchmark data on weakly bound systems. These results can help us to understand the performance of current DFT based methods, and may aid in the development of improved approaches. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3569134

    Hypermedia in the Ambient Wood

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    The Ambient Wood project, carried out as part of the Equator IRC, set out to provide an augmented learning experience for children in an outdoor environment. Using a variety of devices, the children gathered information about the woodland habitats performing basic scientific enquiry and hypothesis testing. In this paper we describe the supporting information infrastructure used in the project, focusing on how hypermedia tools and techniques were used to structure and deliver the information to the children helping to orchestrate the learning activities

    The Ambient Wood Journals - Replaying the Experience

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    The Ambient Wood project aims to facilitate a learning experience using an adaptive infrastructure in an outdoor environment. This involves sensor technology, virtual world orchestration, and a wide range of devices ranging from hand-held computers to speakers hidden in trees. Whilst performing user trials of the Wood, the activities of children participating in the experiments were recorded in detailed log files. An aim of the project has been to replay these log files using adaptive hypermedia techniques to enable the children to further reflect on their experience back in the classroom environment
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