Journal of Digital Information (Texas Digital Library - TDL E-Journals)
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Fault-tolerant Fulltext Search for Large Multilingual Scientific Text Corpora
No full textIn the work reported here, we present a new way of performing fault-tolerant fulltext retrieval on large text corpora, such as scientific encyclopedias. The weighted pattern morphing (WPM) technique introduced in this paper overcomes disadvantages of both the popular edit distance measure and the Soundex code approaches, yet keeping their flexibility. This algorithm handles phonetic similarities; common typing errors such as omission or transposition of letters, and inconsistent usage of abbreviations and hyphenation. After showing how WPM can be implemented efficiently, we present a novel method of how the weights of the internal penalty matrix can be automatically adjusted for even better results. Though the described technique can be applied without prior knowledge of actual user patterns, re-examination with a large number of online-user\u27s patterns proves the portability of this fine-tuning approach. We further show how shifting the penalty matrix from one language to another can be accomplished. The described WPM technique is integrated into a large commercial pharmaceutical encyclopedia CDROM, an online dermatological encyclopedia, and an online-reference encyclopedia of parasitology research, thus also proving its "road capability"
An Evaluation of Document Keyphrase Sets
No full textKeywords and keyphrases have many useful roles as document surrogates and descriptors, but the manual production of keyphrase metadata for large digital library collections is at best expensive and time-consuming, and at worst logistically impossible. Algorithms for keyphrase extraction like Kea and Extractor produce a set of phrases that are associated with a document. Though these sets are often utilized as a group, keyphrase extraction is usually evaluated by measuring the quality of individual keyphrases. This paper reports an assessment that asks human assessors to rate entire sets of keyphrases produced by Kea, Extractor and document authors. The results provide further evidence that human assessors rate all three sources highly (with some caveats), but show that the relationship between the quality of the phrases in a set and the set as a whole is not always simple. Choosing the best individual phrases will not necessarily produce the best set; combinations of lesser phrases may result in better overall quality
Macro Approaches to Digital Searching and Secondary Research
No full textThe use of digital information can be approached from more than one angle. The main emphasis over the past decade has been on making a few basic tools (for instance, browsers and search mechanisms) powerful, versatile and easy to use. Coleman and Oxnam (2002) suggest both improving the usability of current tools and developing new ones. This article suggests focusing on the use of tools for searching digital information. The power of a search mechanism depends not only on how it is constructed but also on how it is used. Coleman and Oxnam ask: "How can interactional digital libraries enhance and augment human capabilities?" I ask a related question: "How can we use current tools such as search mechanisms more effectively?" Coleman and Oxnam wrote their article in the form of a challenge to JoDI readers, authors and researchers in the realm of interactional digital libraries. In a similar spirit, this article can be considered an initial investigation of this question
Adaptive Organization of Tabular Data for Display
No full textTabular representations of information can be organized so that the subject distance between adjacent columns is low, bringing related materials together. In cases where data is available on all topics, the subject distance between table columns and rows can be formally shown to be minimized. A variety of Gray codes may be used for ordering tabular rows and columns. Subject features in the Gray code may be ordered so that the coding system used is one that has a lower inter-column subject distance than with many other codes. Methods by which user preferences may be incorporated are described. The system optionally may display unrequested columns of data that are related to requested data
KOS at your Service: Programmatic Access to Knowledge Organisation Systems
No full textThe lack of standardised access and interchange formats for knowledge organisation systems (KOS) are a barrier to their interoperability and wider use in automated Web and retrieval applications. Programmatic access to thesaurus (and other types of KOS) resources requires a commonly agreed distributed service protocol, building on lower-level standards, such as Web services. This paper reflects on our experiences in building a Web demonstrator of some novel thesaurus browsing and search tools, developed as part of a research project on the role of the thesaurus in controlled vocabulary retrieval applications. The Web system provides dynamically generated interface components for finding terms and browsing the thesaurus, building a query and returning ranked results using term expansion from a collections database. We designed a custom application programming interface of lower-level thesaurus functions to support the various user interface requirements of the application demonstrator. Based on our experience with developing the system, we review the literature on protocols for distributed access to thesauri and offer suggestions for further development of thesaurus service protocols. The FACET project, its semantic expansion and ranked result, multi-concept matching capabilities are briefly outlined. We provide a detailed description of key elements of the Web demonstrator and their rationale, together with a discussion of the data elements required by the different interface components. Existing proposals (Ceres, Zthes and ADL) for thesaurus service protocols are reviewed. The paper concludes by reflecting on lessons from constructing the Web demonstrator and implications for separating the service protocol from the interface. We argue that basing distributed protocol services on the atomic elements of thesaurus data structures and standard relationships is not necessarily the best approach. Client interfaces with similar components to the Web demonstrator require a service-oriented approach, with base services that group primitive KOS data elements (via their relationships) into composites. This leads to a proposal for a novel, unified semantic expansion service, which can be used both for specifying composite display formats and for query expansion services. Thesaurus (KOS) representations and service protocols for retrieval are closely linked. A service protocol should be explicitly expressed in terms of a well defined but extensible set of KOS data elements and relationships
Towards a Semantic Web for Culture
No full textToday\u27s semantic Web deals with meaning in a very restricted sense and offers static solutions. This is adequate for many scientific, technical purposes and for business transactions requiring machine-to-machine communication, but does not answer the needs of culture. Science, technology and business are concerned primarily with the latest findings, the state of the art, i.e. the paradigm or dominant world-view of the day. In this context, history is considered non-essential because it deals with things that are out of date.
By contrast, culture faces a much larger challenge, namely, to re-present changes in ways of knowing; changing meanings in different places at a given time (synchronically) and over time (diachronically). Culture is about both objects and the commentaries on them; about a cumulative body of knowledge; about collective memory and heritage. Here, history plays a central role and older does not mean less important or less relevant. Hence, a Leonardo painting that is 400 years old, or a Greek statue that is 2500 years old, typically have richer commentaries and are often more valuable than their contemporary equivalents. In this context, the science of meaning (semantics) is necessarily much more complex than semantic primitives. A semantic Web in the cultural domain must enable us to trace how meaning and knowledge organisation have evolved historically in different cultures.
The paper examines five issues to address this challenge:
1. different world-views (i.e. a shift from substance to function and from ontology to multiple ontologies);
2. developments in definitions and meaning;
3. distinctions between words and concepts;
4. new classes of relations;
5. dynamic models of knowledge organisation.
These issues reveal that historical dimensions of cultural diversity in knowledge organisation are also central to classification of biological diversity.
New ways are proposed of visualizing knowledge using a time/space horizon to distinguish between universals and particulars. It is suggested that new visualization methods make possible a history of questions as well as of answers, thus enabling dynamic access to cultural and historical dimensions of knowledge. Unlike earlier media, which were limited to recording factual dimensions of collective memory, digital media enable us to explore theories, ways of perceiving, ways of knowing; to enter into other mindsets and world-views and thus to attain novel insights and new levels of tolerance. Some practical consequences are outlined
You\u27ve Got Hypertext
No full textThe paper considers possible "future everyday hypertext systems". To ground the discussion, we look first at the functional and conceptual definitions of hypertext that have evolved in the hypertext research community. We then consider these definitions against the Web, the best known current everyday hypertext, but one that the hypertext community has regarded as only partially a hypertext system at best. We propose, however, that a full, rich hypertext is alive and well and living in an equally successful everyday system: that system is email. We look at how email meets the criteria, both functionally and conceptually, for rich hypertext. We then use email-as-hypertext as our touchstone for assessing future hypertext systems. In particular, we consider the newest system on the Web event horizon, the Semantic Web, and show how the potential hypertextness of the Semantic Web has been anticipated by pre- and co-Web hypertext research systems. We consider how, if informed by the attributes of our email model, the Semantic Web may be able to break away from the limited hypertext model of the Web to become a rich, everyday hypertext system like email. We present three current hypertext research efforts that use the Semantic Web platform to show how these may be seen to embody such email-like hypertext qualities
MetaNet - A Metadata Term Thesaurus to Enable
No full textMetadata interoperability is a fundamental requirement for access to information within networked knowledge organization systems. The Harmony international digital library project [1] has developed a common underlying data model (the ABC model) to enable the scalable mapping of metadata descriptions across domains and media types. The ABC model [2] provides a set of basic building blocks for metadata modeling and recognizes the importance of \u27events\u27 to describe unambiguously metadata for objects with a complex history. To test and evaluate the interoperability capabilities of this model, we applied it to some real multimedia examples and analysed the results of mapping from the ABC model to various different metadata domains using XSLT [3]. This work revealed serious limitations in the ability of XSLT to support flexible dynamic semantic mapping. To overcome this, we developed MetaNet [4], a metadata term thesaurus which provides the additional semantic knowledge that is non-existent within declarative XML-encoded metadata descriptions. This paper describes MetaNet, its RDF Schema [5] representation and a hybrid mapping approach which combines the structural and syntactic mapping capabilities of XSLT with the semantic knowledge of MetaNet, to enable flexible and dynamic mapping among metadata standards
Hypertext Structure as the Event of Connection
No full textHypertext linking is regarded as a key element of identifying or building hypertext structure. However, links provide a nonlinguistic excess that has generally been under-theorised in hypertext criticism. When combined with the role of teleological contextualisation in interpretation links have been largely misunderstood. This paper utilises the example of cinema in relation to hypertext to explore alternative conceptions of links and the relation of meaning in hypertext to narrative teleology suggesting connections to other practices of argument that may be relevant to structure