Thesauri and Semantic Web: Discussion of the Evolution of Thesauri Toward Their Integration With the Semantic Web

M Mercedes Martinez-Gonzalez,Maria-Luisa Alvite-Diez

doi:10.1109/access.2019.2948028

Abstract

Thesauri are Knowledge Organization Systems (KOS), that arise from the consensus of wide communities. They have been in use for many years and are regularly updated. Whereas in the past thesauri were designed for information professionals for indexing and searching, today there is a demand for conceptual vocabularies that enable inferencing by machines. The development of the Semantic Web has brought a new opportunity for thesauri, but thesauri also face the challenge of proving that they add value to it. The evolution of thesauri toward their integration with the Semantic Web is examined. Elements and structures in the thesaurus standard, ISO 25964, and SKOS (Simple Knowledge Organization System), the Semantic Web standard for representing KOS, are reviewed and compared. Moreover, the integrity rules of thesauri are contrasted with the axioms of SKOS. How SKOS has been applied to represent some real thesauri is taken into account. Three thesauri are chosen for this aim: AGROVOC, EuroVoc and the UNESCO Thesaurus. Based on the results of this comparison and analysis, the benefits that Semantic Web technologies offer to thesauri, how thesauri can contribute to the Semantic Web, and the challenges that would help to improve their integration with the Semantic Web are discussed.

Highlights

In the library and information sciences, much effort is devoted to developing tools for organizing large collections of objects such as books or museum artifacts
Our approach is different: we focus on thesauri and compare the solutions that have been used to represent them with Simple Knowledge Organization System (SKOS), looking for commonly used solutions, which seem to be the most solid, and the weakest points, where there are opportunities to continue moving towards shared solutions
It is followed by the analysis of how SKOS-XL and ontologies that extend SKOS have been used to solve some of the difficulties found when thesauri are represented with RDF/SKOS

Summary

Introduction

In the library and information sciences, much effort is devoted to developing tools for organizing large collections of objects such as books or museum artifacts. These tools are known generally as ‘‘Knowledge Organization Systems’’ (KOS) or as ‘‘controlled vocabularies’’. The new ISO 25964 standard defines concisely a thesaurus as a ‘‘controlled and structured vocabulary in which concepts are represented by terms, organized so that relationships between concepts are made explicit, and preferred terms are accompanied by lead-in entries for synonyms or quasi-synonyms’’ [2]. Thousands of thesauri have been created, as Dextre Clarke claims, ‘‘consuming vast amounts of the intellectual effort needed for their construction and maintenance’’

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Discussion

Conclusion