Hugh C. Davis

Towards an integrated information environment with open hypermedia systems

This paper examines open hypermedia systems and presents the case that such systems provide a step forward for dealing with large, dynamic data sets in distributed, heterogeneous environments by allowing users to access and integrate information and processes in richer and more diverse ways than has previously been possible. In particular, the enhanced Microcosm model for open hypermedia is examined, and the ways in which it provides such an environment are discussed. The paper continues by investigating the advantages and the shortcomings of this model and identifies the areas in which further work must be completed before such systems can become widely adopted, such as the granularity of source and destination anchors, editing and version control. Some attempts to provide solutions to these problems are presented and discussed.

FOHM: a fundamental open hypertext model for investigating interoperability between hypertext domains

The Open Hypermedia Systems community has been largely concerned with interoperability between hypertext systems which share the same paradigm. It has evolved a component based framework for this purpose, in which specific but incompatible middleware components are designed for each hypertext domain, such as navigational hypertext, spatial hypertext or taxonomic hypertext. This paper investigates the common features of these domains and introduces FOHM, a Fundamental Open Hypertext Model, which defines a common data model and set of related operations that are applicable for all three domains. Using this layer the paper explores the possible semantics of linking between different hypertext domains, and shows that each can introduce features which benefit the other domains.

Light hypermedia link services: a study of third party application integration

Recently there has been a tendency for the research community to move away from closed hypermedia syustems, towards open hypermedia link services which allow third parties to produce applications so that they are hypertext-enabled. This paper explores the frontiers of this trend by examining the minimum responsibility of an application to co-operate with the underlying link service, and, in the limiting case where the application has not been enabled in any way, it explores the properties and qualities of hypermedia systems that can be produced. A tool, the Universal Viewer, which allows the Microcosm Hypermedia System to co-operate with applications which have not been enabled in introduced and a case study is presented which demonstrates the functionality that may be achieved using entirely third party applications, most of which have not been enabled.

The evolution of metadata from standards to semantics in E-learning applications

Metadata attempts to describe the content, format, purpose and structure of data. Over the past few years, the IEEE-LOM standard has dominated the metadata world in e-learning applications. However, with the advent of the Semantic Web, e-learning applications are beginning to evolve their metadata representation from these standards by adding semantic structure or by converting entirely to semantic representations of structure. This shift enables the implementation of a range of new tools which can reason over the metadata, providing added value from the stored data. This review paper summarizes this evolution of metadata used in e-learning applications from standards to semantic representation.

Referential integrity of links in open hypermedia systems

This paper is concerned with broken hypertext links. These are links which do not refer the reader to the information that was intended by the author of the link. The paper presents three distinct models which have been adopted by various developers for the storage of hypertext links, and considers the problems that may result from adopting each of these models, and reviews and classifies a number of methods that may be adopted for preventing these problems. The link models that are reviewed range from the tightly coupled links implemented by html in the World Wide Web, through to the loosely coupled links adopted by some link server systems. The paper concludes that there can be no universal solution to this problem; rather there is a range of approaches from which hypertext developers must choose a solution appropriate to their needs.

Addressing Interoperability in Open Hypermedia: the Design of the Open Hypermedia Protocol

Abstract Early hypertext systems were monolithic and closed, but newer systems tend to be open, distributed, and support collaboration. While this development has resulted in increased openness and flexibility, integration or adaptation of various different tools (such as content editors, viewers, services, or even other link servers) has remained a tedious task. Many developers were implementing essentially similar components, simply for the benefit of having their own platform on which to experiment with hypertexts. The open hypermedia community is addressing this issue of interoperability between open hypermedia systems. The goal of this effort is to provide an open framework that can be used by application developers outside the community to construct more powerful hypermedia-aware applications. The design and evolution of this framework is presented along with the requirements that drove its development. The framework has matured to the point where it has supported the creation of a number of researc...

Media-based navigation with generic links

Microcosm is an open architecture hypermedia system in which documents remain in their native format and link information is held in separate link databases. This has facilitated the introduction of generic links which, once authored from a text string to a destination anchor, may be followed from any occurrence of the text string in any document. The generic link provides substantial reductions in authoring effort for large hypermedia systems, but the limitation of the generic link to text string source anchors needed to be addressed. This paper describes extensions to the Microcosm architecture to create MAVIS, Microcosm Architecture for Video, Image and Sound, in which generic links maybe used from both text and non-text media. ‘This development makes it possible to navigate through non-text media using content as the key and, through the facilities of the dynamic link, content based retrieval is also available. Examples of content based navigation with image, video and sound are presented.

Bootstrapping a Culture of Sharing to Facilitate Open Educational Resources

It seems self-evident that life for teachers would be simplified if there existed a large corpus of relevant resources that was available for them to reuse and for inquisitive students to download. The learning object community has worked for the past decade and more to provide the necessary infrastructure, standards, and specifications to facilitate such beneficial activity, but the take-up has been disappointingly small, particularly in University and Higher Education, which is the subject of this research. The problem has been that practitioners have not deposited their teaching resources, or have not made them openly available, in the quantity that would achieve critical mass for uptake. EdShare and the Language Box are two initiatives that have concentrated on the issue of facilitating and improving the practice of sharing, the former in an institutional setting and the latter in a subject community of practice. This paper describes and analyzes the motivations for these projects, the design decisions they took in implementing their repositories, the approaches they took to change agency and practice within their communities, and the changes, in practice, that have so far been observed. The contribution of this paper is an improved understanding of how to encourage educational communities to share.

Hypertext link integrity

Hypertext links are connections between documents or parts of documents. Generally the ends of links are represented by some kind of a reference to a document or part of a document. When documents are moved or changed these references may cease to resolve to the correct places. This paper reflects on the causes of this problem and reviews techniques that may be used to maintain link integrity. Categories and Subject Descriptors: H.5.4 (Information Interfaces and Presentation): Hypertext/Hypermedia - Architectures

Semantic Technologies for Learning and Teaching in the Web 2.0 Era

Deploying semantic tools and services over a field of linked data could be a way to address many current challenges of higher education. The strengths of semantic technologies for learning and teaching, and their benefits for digital libraries, virtual communities, and e-learning, have been a major topic of discussion during recent years. Experts argue that semantic technologies can enhance the advanced learning experience by using the expressive power of metadata to describe learning content, people, and services, and then matching these intelligently.