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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A Top-Domain Ontology for Software testing.

Srikanth, Rakesh, Ahmad, Asman January 2016 (has links)
In software testing process a large amount of information is required and generated. This information can be stored as knowledge that needs to be managed and maintained using principles of knowledge management. Ontologies can act as a bridge by representing this testing knowledge in an accessible and understandable way.
2

The development of a fuzzy expert system to help top decision makers in political and investment domains

Alshayji, Sameera January 2012 (has links)
The world’s increasing interconnectedness and the recent increase in the number of notable regional and international events pose greater and greater challenges for political decision-making, especially the decision to strengthen bilateral economic relationships between friendly nations. Typically, such critical decisions are influenced by certain factors and variables that are based on heterogeneous and vague information that exists in different domains. A serious problem that the decision-maker faces is the difficulty in building efficient political decision support systems (DSS) with heterogeneous factors. One must take many factors into account, for example, language (natural or human language), the availability, or lack thereof, of precise data (vague information), and possible consequences (rule conclusions). The basic concept is a linguistic variable whose values are words rather than numbers and are therefore closer to human intuition. A common language is thus needed to describe such information which requires human knowledge for interpretation. To achieve robustness and efficiency of interpretation, we need to apply a method that can be used to generate high-level knowledge and information integration. Fuzzy logic is based on natural language and is tolerant of imprecise data. Fuzzy logic’s greatest strength lies in its ability to handle imprecise data, and it is perfectly suited for this situation. In this thesis, we propose to use ontology to integrate the scattered information resources from the political and investment domains. The process started with understanding each concept and extracting key ideas and relationships between sets of information by constructing object paradigm ontology. Re-engineering according to the object-paradigm (OP) provided quality for the developed ontology where conceptualization can provide more expressive, reusable object and temporal ontology. Then fuzzy logic has been integrated with ontology. And a fuzzy ontology membership value that reflects the strength of an inter-concept relationship to represent pairs of concepts across ontology has been consistently used. Each concept is assigned a fixed numerical value representing the concept consistency. Concept consistency is computed as a function of strength of all the relationships associated with the concept. Fuzzy expert systems enable one to weigh the consequences (rule conclusions) of certain choices based on vague information. Rule conclusions follow from rules composed of two parts, the if antecedent (input) and the then consequent (output). With fuzzy expert systems, one uses fuzzy logic toolbox graphical user interface (GUI) tools to build up a fuzzy inference system (FIS) to aid in decision-making. This research includes four main phases to develop a prototype architecture for an intelligent DSS that can help top political decision makers.
3

Automatic message annotation and semantic interface for context aware mobile computing

Al-Sultany, Ghaidaa Abdalhussein Billal January 2012 (has links)
In this thesis, the concept of mobile messaging awareness has been investigated by designing and implementing a framework which is able to annotate the short text messages with context ontology for semantic reasoning inference and classification purposes. The annotated metadata of text message keywords are identified and annotated with concepts, entities and knowledge that drawn from ontology without the need of learning process and the proposed framework supports semantic reasoning based messages awareness for categorization purposes. The first stage of the research is developing the framework of facilitating mobile communication with short text annotated messages (SAMS), which facilitates annotating short text message with part of speech tags augmented with an internal and external metadata. In the SAMS framework the annotation process is carried out automatically at the time of composing a message. The obtained metadata is collected from the device’s file system and the message header information which is then accumulated with the message’s tagged keywords to form an XML file, simultaneously. The significance of annotation process is to assist the proposed framework during the search and retrieval processes to identify the tagged keywords and The Semantic Web Technologies are utilised to improve the reasoning mechanism. Later, the proposed framework is further improved “Contextual Ontology based Short Text Messages reasoning (SOIM)”. SOIM further enhances the search capabilities of SAMS by adopting short text message annotation and semantic reasoning capabilities with domain ontology as Domain ontology is modeled into set of ontological knowledge modules that capture features of contextual entities and features of particular event or situation. Fundamentally, the framework SOIM relies on the hierarchical semantic distance to compute an approximated match degree of new set of relevant keywords to their corresponding abstract class in the domain ontology. Adopting contextual ontology leverages the framework performance to enhance the text comprehension and message categorization. Fuzzy Sets and Rough Sets theory have been integrated with SOIM to improve the inference capabilities and system efficiency. Since SOIM is based on the degree of similarity to choose the matched pattern to the message, the issue of choosing the best-retrieved pattern has arisen during the stage of decision-making. Fuzzy reasoning classifier based rules that adopt the Fuzzy Set theory for decision making have been applied on top of SOIM framework in order to increase the accuracy of the classification process with clearer decision. The issue of uncertainty in the system has been addressed by utilising the Rough Sets theory, in which the irrelevant and indecisive properties which affect the framework efficiency negatively have been ignored during the matching process.
4

Représentation sémantique des biomarqueurs d’imagerie dans le domaine médical / Semantic representation of imaging biomarkers in the medical field

Amdouni, Emna 07 December 2017 (has links)
En médecine personnalisée, les mesures et les descriptions radiologiques jouent un rôle important. En particulier, elles facilitent aux cliniciens l’établissement du diagnostic, la prise de décision thérapeutique ainsi que le suivi de la réponse au traitement. On peut citer à titre d’exemple, les critères d’évaluation RECIST (en anglais Response Evaluation Criteria in Solid Tumors). De nombreuses études de corrélation en radiologie-pathologie montrent que les caractéristiques d'imagerie quantitative et qualitative sont associées aux altérations génétiques et à l'expression des gènes. Par conséquent, une gestion appropriée des phénotypes d'imagerie est nécessaire pour faciliter leur utilisation et leur réutilisation dans de multiples études concernant les mesures radiologiques. En littérature, les mesures radiologiques qui caractérisent les processus biologiques des sujets imagés sont appelées biomarqueurs d'imagerie. L'objectif principal de cette thèse est de proposer une conceptualisation ontologique des biomarqueurs d'imagerie pour rendre leur sens explicite et formel, améliorer le reporting structuré des images. La première partie de la thèse présente une ontologie générique qui définit les aspects fondamentaux du concept de biomarqueur d'imagerie, à savoir : les caractéristiques biologiques mesurées, les protocoles de mesure et les rôles des biomarqueurs imagerie dans la prise de décision. La deuxième partie de la thèse traite des problèmes de modélisation sémantique liés à la description des données d’observation en neuro-imagerie en utilisant les connaissances biomédicales existantes. Ainsi, elle propose des solutions ''pertinentes'' aux situations les plus typiques qui doivent être modélisées dans le glioblastome. / In personalized medicine, radiological measurements and observations play an important role; in particular they help clinicians in making their diagnosis, selecting the appropriate treatment and monitoring the therapeutic response to an intervention as for example the Response Evaluation Criteria in Solid Tumors (RECIST). Many radiology-pathology correlation studies show that quantitative and qualitative imaging features are associated to genetic alterations and gene expression. Therefore, suitable management of imaging phenotypes is needed to facilitate their use and reuse in multiple studies regarding radiological measurements. In litterature, radiological measurements that characterize biological processes of imaged subjects are called imaging biomarkers. The main objective of this thesis is to propose an ontological conceptualisation of imaging biomarkers to make their meaning explicit and formal, improve structured reporting of images. The first part of the thesis presents a generic ontology that defines basic aspects of the imaging biomarker concept, namely; measured biological characteristic, measurement protocols and role in decision making application. The second part of the thesis adresses important semantic modeling challenges related to the description of neuro-imaging data using existing biomedical knowledge, as well as it proposes some “relevant” solutions to the most typical situations that need to be modeled in glioblastoma.
5

Ontology-based Spatio-temporal Video Management System

Simsek, Atakan 01 September 2009 (has links) (PDF)
In this thesis, a system, called Ontology-Based Spatio-Temporal Video Management System (OntoVMS) is developed in order to supply a framework which can be used for semantic data modeling and querying in video files. OntoVMS supports semantic data modeling which can be divided into concept modeling, spatio-temporal relation and trajectory data modeling. The system uses Rhizomik MPEG-7 Ontology as the core ontology. Moreover ontology expression capability is extended by automatically attaching domain ontologies. OntoVMS supports querying of all spatial relations such as directional relations (north, south ...), mixed directional relations (northeast, southwest ...), distance relations (near, far), positional relations (above, below ...) and topological relations (inside, touch ...) / temporal relations such as starts, equal, precedes / and trajectories of objects of interest. In order to enhance querying capability, compound queries are added to the framework so that the user can combine simple queries by using &quot / (&quot / , &quot / )&quot / , &quot / AND&quot / and &quot / OR&quot / operators. Finally, the use of the system is demonstrated with a semi-automatic face annotation tool.
6

Vers une mise en observation des systèmes énergétiques territoriaux : une approche géographique pour territorialiser l'énergie / Towards the observation of Territorial Energy Systems : a geographical design approach for energy territorialisation

Fléty, Yann 28 January 2014 (has links)
Pouvoir agir sur un système implique de le comprendre et donc de le connaitre. L’objectif de ce travail est defournir un cadre général d’interprétation de l’information géographique, ainsi qu’un canevas méthodologiquesur lequel s’appuyer, pour l’appréhension des liens territoire-énergie dans le contexte d’un observatoireterritorial. Une caractérisation des planifications territoriale et énergétique nous a tout d’abord permis dedresser le constat du renouvellement de leurs contextes et évolutions similaires, en matière dedécentralisation et de considérations environnementales notamment. Ce changement d’échelles de réflexionrenouvelle les modes d’action publique et questionne la place du local. Les acteurs locaux se trouvent ainsiamenés à jouer un rôle central dans la traduction et la mise en oeuvre concrète d’objectifs de politiqueénergétique dans leurs pratiques de planification territoriale. Dans ce contexte, de fortes attentes en matièrede diagnostic et de prospective, et plus généralement de connaissance sont exprimées par les collectivités encharge de piloter, à l’échelle de leur territoire de référence, une planification territoriale énergétique. En effet,les fonctions territoriales (habiter, travailler, se déplacer,...) sont elles-mêmes à l’origine des formes et desstructures territoriales dont la dimension prospective ne peut se dissocier des questions d’aménagement duterritoire et d’énergie. Pour parvenir à approcher cette énergie indispensable, omniprésente et organisatricedu territoire, une lecture systémique et territorialisée des liens territoire-énergie est proposée via le concept deSystème Energétique Territorial. Elle illustre l’importance des interactions entre un territoire et son systèmeénergétique, et plus précisément, la dépendance réciproque des processus énergétiques et des processusterritoriaux, traduisant ainsi le besoin de territorialiser l’énergie. Nous avons en ce sens proposé unedémarche de conception d’un cadre d’analyse des liens territoire-énergie, démarche de modélisationconceptuelle du réel notamment centrée sur des questions de sémantique. Cette démarche considère troiséléments : un métamodèle, une ontologie légère pré-consensuelle et des modèles conceptuels par indicateurs.L’exemple d’intégration d’un indicateur original, les « Étiquettes Énergétiques Territoriales mobilitésquotidiennes-habitat » permet un premier peuplement de l’ontologie. Si qualifier les liens Territoire-Énergien’a rien d’évident notamment au regard de la multitude des processus, échelles ou contraintes liées auxdonnées, une difficulté supplémentaire demeure dans la manipulation de chacun de ces deux concepts auxacceptions multiples. Ainsi, l’apport de ce travail réside dans la démonstration de la pertinence d’uneapproche territoriale de l’énergie, ainsi que la proposition d’une démarche géographique de conception pourune mise en observation des Systèmes Énergétiques Territoriaux. / Having an effect on a system calls for a thorough knowledge of it. The main goal of this research is toprovide a general framework for the interpretation of geographic information, as well as a methodologicalframework to understand the interrelations between territory and energy in the context of a territorialobservatory. A literature review of energy planning on the one hand and spatial planning on the other revealssimilar developments in the two fields, in particular in terms of decentralisation and environmental concerns.The change of geographical scale chosen for the analysis brings new possibilities for public intervention. Inthis context, therefore, local authorities have a key role to play in implementing energy policy goals in theirplanning practices. They need analysis and prospective studies, as well as basic knowledge to carry outterritorial energy planning. Indeed, the socio-spatial functions (living, travelling, working, etc.) arethemselves at the root of spatial layout, urban forms and settlement structures. Those functions cannot bedisassociated from questions of land use and energy. So, to understand energy which is vital, ubiquitous, andresponsible for the organisation of territory, a systemic approach is proposed: the Territorial Energy System.It illustrates the importance of the interactions between a territory and its energy system, and more precisely,the interdependence between energy processes and territorial ones. We propose a design approach in thecontext of an observatory, and more precisely conceptual models, to analyse the territory-energyinterrelations, especially with a focus on semantic dimensions. This approach combines three elements: ameta-model, a light and pre-consensus domain ontology, and individual conceptual data models for eachindicator. An original indicator is then used for a first ontology population: the territorial energy label.Characterising the interrelations between territory and energy is non-trivial, dealing with the variety ofprocesses, scales or data constraints and the numerous meanings of those two concepts. The maincontributions of this research is firstly to demonstrate the relevance of a territorial perspective on energy, aswell as presenting a geographical design approach to conceptualising the observation of territorial energysystems in a territorial observatory
7

Princípios metodológicos para a construção de uma ontologia baseada na semântica de frames

Müller, Carolina 26 August 2015 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2015-10-28T12:55:53Z No. of bitstreams: 1 Carolina Müller_.pdf: 7010149 bytes, checksum: dea9fca340fddaec536a1d6bc89582d7 (MD5) / Made available in DSpace on 2015-10-28T12:55:53Z (GMT). No. of bitstreams: 1 Carolina Müller_.pdf: 7010149 bytes, checksum: dea9fca340fddaec536a1d6bc89582d7 (MD5) Previous issue date: 2015-08-26 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CNJ/CAPES - Conselho Nacional de Justiça / Esta tese apresenta uma metodologia fundamentada na teoria da Semântica de Frames (FILLMORE, 1982) para a construção de ontologias de domínio. A metodologia proposta segue passos reinterpretados a partir de metodologias vigentes, porém embasados no conceito de frames semânticos (cenas com seus participantes e diferentes papéis) para a descrição dos significados. O principal objetivo desta pesquisa reside em refletir sobre as convergências entre ontologias (GRUBER, 1996; GUARINO, 1998) e frames, de modo a acreditar-se que a combinação destas duas formas de organizar o conhecimento garantem a representação mais precisa de conceitos do domínio jurídico. A proposta assume que a inserção da informação dos frames, especialmente a relacionada aos diferentes papéis que os participantes podem exercer, é capaz de prover uma descrição detalhada dos conceitos do domínio e, assim, prover mais significado à ontologia. A metodologia prevê cinco etapas que correspondem ao ciclo de vida da ontologia, porém têm como foco o estágio de conceitualização, no qual são descritos os conceitos do domínio através do uso dos frames. Realizou-se a construção de uma ontologia piloto tomando como base os Juizados Especiais Criminais, cujos processos tramitam em primeira instância e correspondem a crimes de menor potencial ofensivo. O estudo resultou em uma metodologia linguística para o desenvolvimento de ontologias de domínio capaz de ampliar a descrição dos conceitos, provendo detalhamentos sobre os eventos, seus participantes e os diferentes papéis por eles exercidos, de modo a prover mais significado à estrutura ontológica, contribuindo com a recuperação da informação. A etapa de avaliação da ontologia foi realizada com base no cálculo da abrangência, obtendo um resultado de 84,4% de informações representáveis na estrutura ontológica, demonstrando a proficuidade da metodologia proposta no que se refere à identificação de informações relevantes advindas dos documentos jurídicos. / This thesis presents a methodology for the construction of domain ontologies based on the theory of Semantic Frames (FILLMORE, 1982). The proposed methodology reinterprets existents methodologies, but grounded in the concept of semantic frames (scenes of its participants and different roles) for the description of meanings. The main objective of this research lies in reflecting on the similarities between ontologies (GRUBER, 1996; GUARINO, 1998) and frames in order to believe that the combination of these two ways of organizing knowledge ensures the most accurate representation of legal domain concepts. The proposal assumes the inclusion of information of frames, especially those related to the different roles that scene participants may assume, is capable of providing a detailed description of domain concepts and thus provide more meaning to the ontology. The methodology provides five steps that correspond to the ontology life cycle, but are focused on the conceptualization stage, in which describes the domain concepts through the use of frames. A pilot ontology was built based on the Special Criminal Courts context, whose cases proceed through at first instance and account for crimes of lesser offensive potential. The study resulted in a linguistic methodology to develop domain ontologies able to expand the description of the concepts, providing detailing of events, its participants and the different roles they assume in order to provide more meaning to the ontological structure, aiming at contributing specially in information retrieval of documents. The evaluation stage of ontology was based on calculation of coverage (recall), getting a score of 84.4% of representable information on the ontological structure, demonstrating the usefulness of the proposed methodology with regard to the identification of relevant information from legal documents
8

Conceptual modeling of formal and material relations applied to ontologies / Modelagem conceitual das relações formais e materiais aplicadas a ontologias

Linck, Ricardo Ramos January 2014 (has links)
Ontologias representam uma conceitualização compartilhada de uma comunidade de conhecimento. São construídas a partir da descrição dos significados dos conceitos, descritos através de seus atributos e dos relacionamentos entre os conceitos. Conceitos se referem ao objeto da conceitualização, o universo do discurso. São caracterizados por seus atributos e domínios de valores possíveis. Relacionamentos são utilizados para descreverem de que forma os conceitos se estruturam no mundo. Nas ontologias todos os conceitos são hierarquicamente definidos, porém existem outros relacionamentos que são definicionais, dando identidade aos conceitos e sentido ao mundo. Além dos relacionamentos de subsunção que constroem as taxonomias de conceitos, outras relações formais e materiais auxiliam na estruturação do domínio e na definição conceitual. As ferramentas de modelagem, no entanto, ainda são falhas em diferenciar os vários tipos de relacionamentos formais e materiais para atribuir as possibilidades de raciocínio automático. Em especial, relacionamentos mereológicos e partonômicos carecem de opções de implementação que permitam extrair o potencial semântico da modelagem. Este projeto de pesquisa tem como ponto de partida o estudo da literatura sobre ontologias e relações, em especial sobre relações formais e materiais, incluindo relações mereológicas e partonômicas, revisando os princípios encontrados nas ontologias. Além disso, nós identificamos os fundamentos teóricos das relações e analisamos a aplicação dos conceitos das relações sobre as principais ontologias de fundamentação em prática na atualidade. Na sequência, a partir das propostas levantadas, este trabalho propõe uma alternativa para a modelagem conceitual destas relações em uma ontologia de domínio visual. Esta alternativa foi disponibilizada na ferramenta de construção de ontologias do Projeto Obaitá, a qual está sendo desenvolvida pelo Grupo de Pesquisa de Bancos de Dados Inteligentes (BDI) da UFRGS. / Ontologies represent a shared conceptualization of a knowledge community. They are built from the description of the meaning of concepts, expressed through their attributes and their relationships. Concepts refer to the object of conceptualization, the universe of discourse. They are characterized by their attributes and domains of possible values. Relationships are used to describe how the concepts are structured in the world. In ontologies all concepts are hierarchically defined, however there are other relationships that are definitional, giving identity to the concepts and meaning to the world. In addition to the subsumption relationships that build the taxonomies of concepts, other formal and material relations assist in structuring the domain and the conceptual definition. The modeling tools, however, are still deficient in differentiating the various types of formal and material relationships in order to assign the possibilities of automated reasoning. In particular, mereological and partonomic relationships lack of implementation options that allow extracting the semantic potential when modeling. This research project takes as a starting point the study of the literature on ontologies and relations, especially on formal and material relations, including mereological and partonomic relations, reviewing the principles found on ontologies. Furthermore, we identify the theoretical foundations of the relations and analyze the application of the relations concepts to the main foundational ontologies in use nowadays. Following, from the raised proposals, this work proposes an alternative for the conceptual modeling of these relations in a visual domain ontology. This alternative has been made available on the ontology building tool of the Obaitá Project, which is under development by the Intelligent Databases Research Group (BDI) from UFRGS.
9

Proposition d’une ontologie de domaine dédiée à l’annotation d’images spatialisées pour le suivi de la conservation du patrimoine culturel bâti / Proposition to a domain ontology dedicated to spatialized images annotations for the building cultural heritage conseravtion monitoring

Messaoudi, Tommy 12 July 2017 (has links)
Les pratiques de conservation et restauration de monuments historiques requièrent l’élaboration de diagnostics impliquant différents intervenants au sein de contextes d’études pluridisciplinaires. L’état de conservation d’un objet patrimonial est ainsi étudié et décrit au moyen d’observations directes, de sources documentaires et de données analytiques de natures différentes. Les avancées des technologies numériques en matière de collecte, traitement et gestion de données, offrent aujourd’hui une opportunité sans précédent pour intégrer les résultats de ces observations et ces données au sein de systèmes innovants de représentation pour la documentation et la connaissance du patrimoine. Cependant, si une panoplie de nouveaux outils est aujourd’hui à disposition de la communauté des scientifiques et des professionnels du patrimoine, le problème d’une corrélation pertinente de ces données et de ces informations hétérogènes reste peu exploré. Tout d’abord, si ces nouveaux outils permettent aux différents experts de mémoriser et d’analyser leurs observations sur différents supports, les données générées par ces différents experts ne sont généralement pas spatialisées autour d’un même référentiel spatial. En effet, même si toutes ces données se réfèrent à un objet physique commun, les liens entre elles ne peuvent que s’établir par des stratégies d’organisation de fichiers ou par des méthodes d’indexation basées sur des mots clés. Parallèlement, si dans les dernières années plusieurs techniques de numérisation 3D ont été expérimentées dans le but de générer des représentations géométriques denses et précises, les méthodes de traitement et de structuration de ces données 3D ne fournissent pas encore de cadres opérationnels pour l’extraction d'informations pertinentes pour l’analyse et l’interprétation de l’état de conservation. En se positionnant à l'intersection entre les domaines de l’acquisition spatialisée 3D et des systèmes d’informations, ce travail de recherche propose une ontologie de domaine dédiée à l’annotation sémantique de représentations 3D d’objets patrimoniaux visant à la constitution d’un environnement numérique pour la description de l’état de conservation des monuments historiques. Par l’interconnexion de descripteurs qualitatifs (reliés à une formalisation des connaissances du domaine) et qualitatifs, cette ontologie constitue l'échafaudage conceptuel structurant un système d’informations multidimensionnelles dédié à la corrélation spatiale, géométrique et sémantique de jeux d’annotations élaborés par des acteurs multiples et en fonction de niveaux de lecture multiples. / The conservation and restauration of historical monuments require a diagnostic analysis carried out by a multidisciplinary team. The elaboration of the diagnosis of a cultural Heritage Object requires direct observations, the examination of documentary sources as well as of diverse types of analytic data. The great advancements in digital processing, management and data collection opened unprecedented opportunities for integrating results, coming from both observations and derivative data, within innovating representation systems for heritage knowledge and documentation. However, if a range of new tools and data is today available to the scientific community and heritage experts, their correlation and integration with internal/external heterogeneous information is an issue that still remain unexplored. While these innovative tools allow different experts to record and analyze their observations with diverse formats, the results are generally not spatialized and referenced together. Indeed, even though all these data refer to a common physical object, the links between them is based only on file organization strategies or by keyword-based indexation methods. In parallel, in recent years, several 3D digitization technics has been used for generating dense and accurate geometrical representations, but the processing and structuration method of these 3D data don’t include yet an operational framework for retrieving relevant information regarding their conservation state and an interpretative analysis. Positioned in the intersection between 3D spatialized acquisition domain and information management, this research work aims to the creation of a digital framework for recording conservation state description of historical monument throughout the introduction of a functional domain ontology for the semantic annotations of heritage objects 3D representations. The proposed ontology comprises both qualitative (related to a domain knowledge formalization) and quantitative descriptors, constituting the necessary conceptual scaffold for structuring a multidimensional information system dedicated to the correlation of spatial, geometrical and semantic multi-actor annotations in relation to multiple observation levels.
10

Conceptual modeling of formal and material relations applied to ontologies / Modelagem conceitual das relações formais e materiais aplicadas a ontologias

Linck, Ricardo Ramos January 2014 (has links)
Ontologias representam uma conceitualização compartilhada de uma comunidade de conhecimento. São construídas a partir da descrição dos significados dos conceitos, descritos através de seus atributos e dos relacionamentos entre os conceitos. Conceitos se referem ao objeto da conceitualização, o universo do discurso. São caracterizados por seus atributos e domínios de valores possíveis. Relacionamentos são utilizados para descreverem de que forma os conceitos se estruturam no mundo. Nas ontologias todos os conceitos são hierarquicamente definidos, porém existem outros relacionamentos que são definicionais, dando identidade aos conceitos e sentido ao mundo. Além dos relacionamentos de subsunção que constroem as taxonomias de conceitos, outras relações formais e materiais auxiliam na estruturação do domínio e na definição conceitual. As ferramentas de modelagem, no entanto, ainda são falhas em diferenciar os vários tipos de relacionamentos formais e materiais para atribuir as possibilidades de raciocínio automático. Em especial, relacionamentos mereológicos e partonômicos carecem de opções de implementação que permitam extrair o potencial semântico da modelagem. Este projeto de pesquisa tem como ponto de partida o estudo da literatura sobre ontologias e relações, em especial sobre relações formais e materiais, incluindo relações mereológicas e partonômicas, revisando os princípios encontrados nas ontologias. Além disso, nós identificamos os fundamentos teóricos das relações e analisamos a aplicação dos conceitos das relações sobre as principais ontologias de fundamentação em prática na atualidade. Na sequência, a partir das propostas levantadas, este trabalho propõe uma alternativa para a modelagem conceitual destas relações em uma ontologia de domínio visual. Esta alternativa foi disponibilizada na ferramenta de construção de ontologias do Projeto Obaitá, a qual está sendo desenvolvida pelo Grupo de Pesquisa de Bancos de Dados Inteligentes (BDI) da UFRGS. / Ontologies represent a shared conceptualization of a knowledge community. They are built from the description of the meaning of concepts, expressed through their attributes and their relationships. Concepts refer to the object of conceptualization, the universe of discourse. They are characterized by their attributes and domains of possible values. Relationships are used to describe how the concepts are structured in the world. In ontologies all concepts are hierarchically defined, however there are other relationships that are definitional, giving identity to the concepts and meaning to the world. In addition to the subsumption relationships that build the taxonomies of concepts, other formal and material relations assist in structuring the domain and the conceptual definition. The modeling tools, however, are still deficient in differentiating the various types of formal and material relationships in order to assign the possibilities of automated reasoning. In particular, mereological and partonomic relationships lack of implementation options that allow extracting the semantic potential when modeling. This research project takes as a starting point the study of the literature on ontologies and relations, especially on formal and material relations, including mereological and partonomic relations, reviewing the principles found on ontologies. Furthermore, we identify the theoretical foundations of the relations and analyze the application of the relations concepts to the main foundational ontologies in use nowadays. Following, from the raised proposals, this work proposes an alternative for the conceptual modeling of these relations in a visual domain ontology. This alternative has been made available on the ontology building tool of the Obaitá Project, which is under development by the Intelligent Databases Research Group (BDI) from UFRGS.

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