[pt] Um mediador é um componente de software que auxilia o acesso a fontes de dados. Com o advento da Web, a construção de mediadores impõe desafios importantes, tais como a capacidade de fornecer acesso integrado a fontes de dados independentes e dinâmicas e a habilidade de resolver a heterogeneidade semântica entre os esquemas destas fontes. Para lidar com esses desafios, o alinhamento de esquemas é uma questão fundamental. Nesta tese são propostas abordagens de alinhamento de esquemas de classificação (tesauros) e esquemas conceituais, utilizando instâncias como evidências para os mapeamentos. As abordagens propostas são classificadas em dois tipos: adaptativa e a priori, referindo-se, respectivamente, à descoberta dos mapeamentos de forma incremental ou à definição dos mapeamentos antes da implantação do mediador. Por fim, são apresentados experimentos para validação e teste das abordagens propostas. / [en] A mediator is a software component that helps accessing data sources. With the advent of the Web, the design of mediators imposes important challenges, such as the ability of providing integrated access to independent and dynamic data sources and the ability of resolving the semantic heterogeneity between different data source schemas. To deal with these challenges, schema matching is a fundamental issue. In this thesis, matching approaches for classification schemas (thesauri) and conceptual schemas are proposed, using instances as evidences for the mappings. The proposed approaches are classified as adaptative and a priori, referring to, respectively, the discovery of the mappings in an incremental way or the definition of the mappings before the deployment of the mediator. Finally, experiments to validate and test the proposed approaches are presented.

[pt] Alinhamento de esquema é uma questão fundamental em aplicações de banco de dados, tais como mediação de consultas, integração de banco de dados e armazéns de dados. Nesta tese, abordamos inicialmente o alinhamento de catálogos. Um catálogo é um banco de dados simples que contém informações sobre conjuntos de objetos, tipicamente classificados usando-se termos de um dado tesauro. Inicialmente apresentamos uma técnica de alinhamento baseada na noção de similaridade, que se aplica a pares de tesauros e de listas de propriedades. Descrevemos, então, o alinhamento baseado na noção de informação mútua e introduzimos variações que exploram certas heurísticas. Ao final, discutimos resultados experimentais que avaliam a precisão do método e comparam a influência das heurísticas. Após as técnicas para alinhamento de catálogos, nos concentramos no problema mais complexo de alinhamento de dois esquemas descritos em um subconjunto de OWL. Adotamos uma técnica baseada em instâncias e, por isso, assumimos que conjuntos de instâncias de cada esquema estão disponíveis. Decompomos este problema nos subproblemas de alinhamento de vocabulário e de alinhamento de conceitos. Introduzimos também condições suficientes para garantir que o alinhamento de vocabulário induz um alinhamento de conceitos correto. Em seguida, descrevemos uma técnica de alinhamento de esquemas OWL baseada no conceito de similaridade. Finalmente, avaliamos a precisão da técnica usando dados disponíveis na Web. De forma diferente de outras técnicas anteriores baseadas em instâncias, o processo de alinhamento que descrevemos usa funções de similaridade para induzir alinhamento de vocabulários de uma forma não trivial. Ilustramos, também, que a estrutura de esquemas OWL pode nos levar a mapeamentos de conceitos errados e indicamos como evitar tais problemas. / [en] Schema matching is a fundamental issue in many database applications, such as query mediation, database integration, catalog matching and data warehousing. In this thesis, we first address hot to match catalogue schemas. A catalogue is a simple database that holds information about a set of objects, typically classified using terms taken from a given thesaurus. We introduce a matching approach, based on the notion of similarity, which applies to pairs of thesauri and to pairs of lists of properties. We then describe matchings based on cooccurrence of information and introduce variations that explore certain heuristics. Lastly, we discuss experimental results that evaluate the precision of the matchings introduced and that measure the influence of the heuristics. We then focus on the mre complex problem of matching two schemas that belong to an expressive OWL dialect. We adopt an instance-based approach and, therefore, assume that a set of instances from each schema is available. We first decompose the problem of OWL schema matching into the problem of vocabulary matching and the problem of concept mapping. We also introduce sufficient conditions guaranteeing that a vocabulary matching induces a correct concept mapping. Next, we describe OWL schema matching technique based on the notion of similarity. Lastly, we evaluate the precision of the technique using data available on the Web. Unlike any of the previous instance-based techniques, the matching process we describe uses similarity functions to induce vocabulary matchings in a non-trivial, coping with an expressive OWL dialect. We also illustrate, through a set of examples, that the structure of OWL schemas may lead to incorrect concept mappings and indicate how to avoid such pitfalls.

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The purpose of this study is to design a database of resources for rational therapy. An investigation of the current health situation and reorientation towards primary health care (PHC) in South Africa evidenced the need for a database of resources which would meet the demand for rational therapy information made on the Helderberg College Library by various user groups as well as make a contribution to the national health information infrastructure. Rational therapy is viewed as an approach within PHC that is rational, common-sense, wholistic and credible, focusing on the prevention and maintenance of health. A model of the steps in database design was developed. A user study identified users' requirements for design and the conceptual schema was developed. The entities, attributes, relationships and policies were presented and graphically summarised in an Entity-Relationship (E-R) diagram. The conceptual schema is the blueprint for further design and implementation of the database. / Information Science / M.Inf.

The purpose of this study is to design a database of resources for rational therapy. An investigation of the current health situation and reorientation towards primary health care (PHC) in South Africa evidenced the need for a database of resources which would meet the demand for rational therapy information made on the Helderberg College Library by various user groups as well as make a contribution to the national health information infrastructure. Rational therapy is viewed as an approach within PHC that is rational, common-sense, wholistic and credible, focusing on the prevention and maintenance of health. A model of the steps in database design was developed. A user study identified users' requirements for design and the conceptual schema was developed. The entities, attributes, relationships and policies were presented and graphically summarised in an Entity-Relationship (E-R) diagram. The conceptual schema is the blueprint for further design and implementation of the database. / Information Science / M.Inf.

The aim of this work is to compile the linguistic picture of Chods, that is how the word is fixed in the language and the conceptual system of a native speaker. For this purpose, canonical literature has been chosen that thematizes Chods, furthermore some Chod newspapers, corpus syn2013pub and Jindřich's song-books and a few collections of Chod fairytales and legends representing folk literature. This thesis has also drawn upon systemic data, i. e. dictionaries wherein the word Chod can be found in order to record the denotations of this word. Next, the thesis explored the etymology of the word Chod and its synonyms, which also helps to clarify the objective of this work. All the data have been analysed and the connotations, collocations and also attittude towards the dennotation have been gathered that have been featured in more sources to compile the linguistic picture of Chods. Among the most frequent collocations and connotations confirmed in more than one source are Chodsko, border service, privileges and duties of Chods, Kozina and Lomikar, the uprising, Újezd, rebels, defenders against the Germans, nacionalism, freedom, a traditional costume, dialect, music, bagpipes, pies, Chod festival, ceramics, farmers, a banner, a dog, stubborness, repulsion, pride, distinctiveness, togetherness, hard...

The study is a comparative analysis of conceptual metaphors in English and Shona. The objectives of this study were: to compare the metaphorical expressions of English and Shona in the same or similar domains in order to establish on the one hand whether there are similarities and/or differences cross-linguistically and cross-culturally in the metaphorical construal of reality between these two languages and on the other hand, to establish what the underlying motivation is for the similarities and the differences between these two unrelated languages. The thesis also explores the reasons for the similarities in terms of particular assumptions underlying conceptual metaphors, that is, embodiment and ecological motivations. / Linguistics / D. Litt. et Phil. (Linguistics)

The study is a comparative analysis of conceptual metaphors in English and Shona. The objectives of this study were: to compare the metaphorical expressions of English and Shona in the same or similar domains in order to establish on the one hand whether there are similarities and/or differences cross-linguistically and cross-culturally in the metaphorical construal of reality between these two languages and on the other hand, to establish what the underlying motivation is for the similarities and the differences between these two unrelated languages. The thesis also explores the reasons for the similarities in terms of particular assumptions underlying conceptual metaphors, that is, embodiment and ecological motivations. / Linguistics and Modern Languages / D. Litt. et Phil. (Linguistics)