Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-06-05T14:49:44Z No. of bitstreams: 1 ALEX SANDRO DA CUNHA RÊGO - TESE (PPGCC) 2016.pdf: 1783053 bytes, checksum: 4ae3b5d42dde739cfd57afaa25fd7e63 (MD5) / Made available in DSpace on 2018-06-05T14:49:44Z (GMT). No. of bitstreams: 1 ALEX SANDRO DA CUNHA RÊGO - TESE (PPGCC) 2016.pdf: 1783053 bytes, checksum: 4ae3b5d42dde739cfd57afaa25fd7e63 (MD5) Previous issue date: 2016 / As folksonomias têm despontado como ferramentas úteis de gerenciamento online de conteúdo digital. A exemplo dos populares websites Delicious, Flickr e BibSonomy, diariamente os usuários utilizam esses sistemas para efetuar upload de recursos web (e.g., url, fotos, vídeos e referências bibliográficas) e categorizá-los por meio de tags. A ausência de relações semânticas do tipo sinonímia e hiperonímia/hiponímia no espaço de tags das folksonomias reduz a capacidade do usuário de encontrar recursos relevantes. Para mitigar esse problema, muitos trabalhos de pesquisa se apoiam na aplicação de medidas de similaridade para detecção de sinonímia e construção automática de hierarquias de tags por meio de algoritmos heurísticos. Nesta tese de doutorado, o problema de detecção de sinonímia e hiperonímia/hiponímia entre pares de tags é modelado como um problema de classificação em Aprendizado de Máquina. A partir da literatura, várias medidas de similaridade consideradas boas indicadoras de sinonímia e hiperonímia/hiponímia foram identificadas e empregadas como atributos de aprendizagem. A incidência de um severo desbalanceamento e sobreposição de classes motivou a investigação de técnicas de balanceamento para superar ambos os problemas. Resultados experimentais usando dados reais das folksonomias BibSonomy e Delicious mostraram que a abordagem proposta denominada CPDST supera em termos de acurácia o baseline de melhor desempenho nas tarefas de detecção de sinonímia e hiperonímia/hiponímia. Também, aplicou-se a abordagem CPDST no contexto de geração de listas de tags semanticamente relacionadas, com o intuito de prover acesso a recursos adicionais anotados com outros conceitos pertencentes ao domínio da busca. Além da abordagem CPDST, foram propostos dois algoritmos fundamentados no acesso ao WordNet e ConceptNet para sugestão de listas especializadas com tags sinônimas e hipônimas. O resultado de uma avaliação quantitativa demonstrou que a abordagem CPDST provê listas de tags relevantes em relação às listas providas pelos métodos comparados. / Folksonomies have emerged as useful tools for online management of digital content. Popular websites as Delicious, Flickr and BibSonomy are now widespread with thousands of users using them daily to upload digital content (e.g., webpages, photos, videos and bibliographic information) and tagging for later retrieval. The lack of semantic relations such as synonym and hypernym/hyponym in the tag space may diminish the ability of users in finding relevant resources. Many research works in the literature employ similarity measures to detect synonymy and to build hierarchies of tags automatically by means of heuristic algorithms. In this thesis, the problems of synonym and subsumption detection between pairs of tags are cast as a pairwise classification problem. From the literature, several similarity measures that are good indicators of synonymy and subsumption were identified, which are used as learning features. Under this setting, there is a severe class imbalance and class overlapping which motivated us to investigate and employ class imbalance techniques to overcome these problems. A comprehensive set of experiments were conducted on two large real-world datasets of BibSonomy and Delicious systems, showing that the proposed approach named CPDST outperforms the best performing heuristic-based baseline in the tasks of synonym and subsumption detection. CPDST is also applied in the context of tag list generation for providing access to additional resources annotated with other semantically related tags. Besides CPDST approach, two algorithms based on WordNet and ConceptNet accesses are proposed for capturing specifically synonyms and hyponyms. The outcome of an evaluative quantitative analysis showed that CPDST approach yields relevant tag lists in relation to the produced ones by the compared methods.

La thèse se répartit en deux tomes. Les quadriconsonantiques forment deux groupes de radicaux distincts, à savoir : les radicaux de forme ABAB et les radicaux de forme ABCD. L’analyse de ces radicaux, en appliquant la TME (Théorie, Matrice, Etymon) élaborée par G. Bohas, permet de définir leur fonctionnement aux plans sémantique, sémantico phonétique et structurel. La première partie Tome 1 analyse les quadriconsonantiques de forme ABAB. La deuxième partie Tome 2 est consacrée aux quadriconsonantiques de forme ABCD.Concernant les radicaux ABAB, dont la structure est issue d’un redoublement de l’unique étymon AB, le travail d’analyse va plus s’orienter sur la sémantique. Il est démontré que le redoublement ne s’accompagne pas d’une modification sémantique systématique, contrairement à ce que l’on observe dans les parlers d’orient et d’occident.La deuxième partie de la thèse, Tome 2, dans les mêmes conditions que précédemment, étudie les radicaux ABCD dans le cadre de la TME en prenant en compte la contrainte phonétique formulée par Angoujard (1997), notée : CPA. L’objectif est de déterminer leur mode de fonctionnement tant sur le plan structurel que sur le plan sémantico phonétique. L’étude de ces radicaux ABCD ne se limite pas uniquement à montrer le fonctionnement structurel des radicaux mais établit une relation entre la TME de Bohas et la CPA d’Angoujard. / The thesis is divided into two volumes. Quadri-consonant groups form two distinct sets of radicals: ABAB and ABCD pattern radicals. Applying the Theory of Matrices and Etymons (TME) elaborated by Georges Bohas to the analysis of these radicals enables their functioning at the semantic, semantic-phonetic and structural levels to be defined.The first part which constitutes Volume 1 consists in the analysis of ABAB pattern quadric-consonant groups while the second part contained in Volume 2 is devoted to ABCD pattern quadric-consonant groups. In the study of the ABAB pattern radicals, the structure of which is the result of a reduplication of the single AB etymon, the analytical work focuses more on semantics. The analysis demonstrates that reduplication is not accompanied by a systematic semantic modification, contrary to what may be observed in eastern and western dialects.Under the same conditions, the second part of the thesis, Volume 2, consists in a study of ABCD pattern radicals which employs the framework of TME while also taking into consideration the phonetic constraints formulated by Angoujard (1997): CPA. The objective is to determine the modes of functioning of the ABCD pattern radicals on both the structural and semantic-phonetic levels. The study of these ABCD pattern radicals is not merely restricted to demonstrating the structural functioning of these radicals but also establishes a relationship between TME elaborated by Bohas and Angoujard’s CPA.