Topic Maps : da Sintaxe à Semântica
AUTOR(ES)
Giovani Rubert Librelotto
DATA DE PUBLICAÇÃO
2005
RESUMO
According to Topic Map Data Model (Garshol and Moore, 2005), Topic Maps are abstract structures that can encode knowledge and connect this encoded knowledge to relevant information resources. Topic Maps allow a domain knowledge representation in semantic networks, composed of topics and associations. Nowadays, almost all topic maps are built by hand. This kind of edition is time consuming and has important financial costs. There are several tools for topic map edition but they have some limitations like the lack of a topic map semantic validator. In order to cope with a broad range of scenarios, a topic is a very wide concept. On one hand, this makes Topic Maps a convenient model for knowledge representation; but on the other hand, this can also put in risk the topic map consistency. A set of semantic constraints must be imposed to the topic map in order to grant its consistency. The Topic Maps standard does not provide language constructors to specify the semantics. So it is not possible to derive from the standard mechanisms to validate a topic maps against the contextual rules. Therefore it is necessary to improve the ISO 13250 standard adding a support for constraints definition enabling the creation of a processor for topic map automatic validation. The main contribute of this thesis is a constraint language for topic maps called XTche and its processor. XTche language is TMCL-based (Topic Map Constraint Language] (Nishikawa, Moore, and Bogachev, 2004). This language allows to complement the description of the semantic network structure (composed of topic and associations) with schema, contextual, and existence constraints, thus denning the semantics of topic maps that should be preserved. Metamorphosis - an environment that can extract data from information resources and build a topic map according to a specification, validate it, and generate a conceptual navigation over the topic map knowledge - is another contribution of this thesis. Metamorphosis a Topic Maps oriented environment - generates conceptual navigators for heterogenous information resources providing the desired interoperability. Metamorphosis architecture is composed of: (1) Oveia, a processor that builds topic maps. Its core is a processor that extracts the topics instances from the information resources and builds a topic map. It reads and processes the XSDS and XS4TM specifications. The topic map generated by Oveia is stored as an XTM file or alternatively as a relational database following the OntologyDB approach; (2) XTche processor, that consumes the previous XTM file and validates the topic map according to a set of constraints defined in XTche language; (3) Ulisses processor, that produces a whole semantic website based on a valid topic map; this website is a set of pages that displays all the information concerned with topics and associations and provides a conceptual navigation over the semantic network (the topic map).
ASSUNTO(S)
iso 19675 topic maps constraint language iso 13250 topic maps xtche sistemas de computacao topic maps semântica de documentos extensible markup language (xml)
