Faceted knowledge organization systems have sophisticated logical structures, making their representation as linked data a demanding task. The term facet is often used in ambiguous ways: while in thesauri facets only work as semantic categories, in classification schemes they also have syntactic functions. The need to convert the Integrative Levels Classification (ILC) into SKOS stimulated a more general analysis of the different kinds of syntactic facets, as can be represented in terms of RDF properties and their respective domain and range. A nomenclature is proposed, distinguishing between common facets, which can be appended to any class, that is, have an unrestricted domain; and special facets, which are exclusive to some class, that is, have a restricted domain. In both cases, foci can be taken from any other class (unrestricted range: free facets), or only from subclasses of an existing class (parallel facets), or be defined specifically for the present class (bound facets). Examples are given of such cases in ILC and in the Dewey Decimal Classification (DDC).

Plurality of beliefs and theories in different knowledge domains calls for modelling multi-viewpoint ontologies and knowledge organization systems (KOS). A generic theoretical approach recently proposed for heterogeneity representation in KOS was linking each ontological statement to a specific validity scope to determine a set of conditions under which the statement is valid. However, the practical applicability of this approach has yet to be empirically assessed. In addition, there is still a need to investigate the types of inconsistencies that might arise in multi-viewpoint ontologies as well as their possible causes. This study proposes a new framework for systematic analysis and classification of inconsistencies in multi-viewpoint ontologies. The framework is based on eight generic logical structures of ontological statements. To test the validity of the proposed framework, two ontologies from different knowledge domains were examined. We found that only three of the eight structures led to inconsistencies in both ontologies, while the other two structures were always present in logically consistent statements. The study has practical implications for building diversified and personalized knowledge systems.

In his Categories, Aristotle details the kinds of being that exist, along with what can be understood and predicated of existing things. Most notably within this work, Aristotle advances a set of ten, top-level categories that can be used to classify all kinds of being. Even today, the influence of the Categories is felt in many domains, particularly in knowledge organization (KO). Here, Aristotle’s Categories bear deep, long-standing connections with works examining categorization, subject analysis, and theory of classification. Though its relation to ontology might seem obvious, connections to KO perspectives on knowledge organization systems (KOSs) and ontological modeling are curiously lacking. The aim of this work is to offer a re-examination of the Categories as a KOS, particularly through the lens of the KO field’s understandings of ontology. Utilizing Zeng’s classification of KOSs as a theoretical framework, this study draws parallels between the first two sections of the Categories and the defining features of ontologies and offers an initial ontological model of this work. The results of this re-examination stand to offer a new view of a fundamental work in the KO canon, draw further connections between past and present perspectives in KO, and further contribute to the theoretical grounding of contemporary KOS research and practice.

It is suggested that the knowledge organization (KO) field places greater emphasis on basic research that examines the sociology of KO systems (KOS) and the broader, environmental reasons for the development of both formal and informal KOS. This approach is contrasted with applied KO, which focuses on the practical construction or improvement of specific KOS. The preponderance of applied research in the field of KO is confirmed, at least within the document-centric strand more closely aligned with library and information science, through a survey of articles in the Knowledge Organization journal published between 2009 and 2018. The survey utilized the Frascati Manual definitions for basic and applied research, and referenced Tennis’s classification of KO research (2008). There is considerable potential for building on the critical tradition of KO, with various areas ripe for further sociological investigation. A sociology of KOS could also be accommodated in the popular KO approach of domain analysis.

The massive and unstoppable emergence of electronic books in libraries has altered their organization. This disruptive technology has led to structural changes. Currently, an e-book exists only if its metadata exists. The objective of this article is to analyse the impact that the massive incorporation of electronic books in university library systems is having in the processes of assignment of subject headings and classification codes. We carried out a survey of more than six hundred libraries, which means almost all the university libraries in Portugal, Spain, England, United States, Brazil, Sweden, Norway, Finland and Australia. From the results obtained, it is deduced that: 1) librarians expect e-books to be provided with descriptive metadata related to the subject headings and classification codes; 2) the bibliographic records provided by publishers/providers seem to be improvable; 3) the quality of the metadata provided by the providers does not seem to be taken into account when selecting publishers for the purchase; 4) the discovery tools are also clearly improvable; 5) it seems that there is no “frustration” or “stress” among librarians about the changes produced in relation to technical processes; and, 6) it does not seem that we are facing a paradigm shift motivated by these issues.