Isa Mara da Rosa Alves

The construction of a juridical ontology

The need for the representation of both semantics and common sense and its organization in a lexical database or knowledge base has motivated the development of large projects, such as Wordnets, CYC and Mikrokosmos. Besides the generic bases, another approach is the construction of ontologies for specific domains. Among the advantages of such approach there is the possibility of a greater and more detailed coverage of a specific domain and its terminology. Domain ontologies are important resources in several tasks related to the language processing, especially in those related to information retrieval and extraction in textual bases. Information retrieval or even question and answer systems can benefit from the domain knowledge represented in an ontology. Besides embracing the terminology of the field, the ontology makes the relationships among the terms explicit.

A Linguistic Approach to Identify the Affective Dimension Expressed in Textual Messages

The digital mediation resources used in Distance Education can hinder the teachers perception about the students state of mind. However, the textual expression in natural language is widely encouraged in most Distance Education courses, through the use of Virtual Learning Environments and other digital tools. This fact has motivated research efforts in order to identify feelings expressed by students in textual messages. A significant part of the known approaches in this area apply textual analysis without a deep linguistic representation, which can lead to some weakness in the results obtained. This paper reports an approach using theories of Computational Lexical Semantics for the representation of the lexicon of emotion. The methodology was developed through studies regarding corpus analysis, lexical unit description, and the implementation of a computational system to identify the feelings expressed in the textual messages in natural language, using the lexicon of emotion. This system was used in evaluation experiments that indicate improvements when comparing the adopted approach with other similar approaches.

A semântica adjetival e sua representação em uma ontologia de domínio jurídico

Este trabalho faz parte de uma serie de estudos que temos feito sobre a semântica dos adjetivos do dominio juridico, visando a sua formalizacao e inclusao em uma ontologia que possa contribuir para o aperfeicoamento de sistemas de busca e extracao de informacoes juridicas na web. Este artigo discute as dificuldades para a inclusao dos adjetivos em uma ontologia juridica, bem como a validade do significado adjetival para a recuperacao de informacoes. Para a analise linguistica dos adjetivos, optamos por uma abordagem baseada em relacoes semânticas. A ontologia proposta tem como objetivo futuro o agrupamento desses adjetivos sob conceitos de top-level e a interligacao da ontologia a uma rede de ontologias juridico-semânticas. Para a presente analise, utilizamos seis textos juridicos extraidos, via internet, do Instituto das Tecnologias de Informacao na Justica de Portugal. Palavras-chave: adjetivos, semântica lexical, ontologias, recuperacao de informacao.

Extração de informações e web semântica: a importância da semântica verbal

The objective of this paper is to present a descriptive study of verbs of the university domain aiming at the construction of an ontology which may contribute towards the enhancement of Natural Language Processing (NLP) systems, particularly to the construction of an on-line Information Retrieval System. Using a special tool for extraction pourposes, we analized verb valence and thematic roles according to the aproach proposed by Borba (1996) and we got a typology to describe stative verbs of the domain. Key words: verbal semantics, thematic roles, semantic web, ontology, Information Retrieval Systems.

Synonymy for Query Expansion in Information Search

This paper presents our work towards the use of domain ontology for information search in university web sites. We evaluate the adequacy of semantic relations for query expansion. We discuss, in particular, synonymy and its role in information search on specific domains.