Creation and extension of ontologies for describing communications in the context of organizations

Thesis submitted to Faculdade de Ciências e Tecnologia of the Universidade Nova de Lisboa, in partial fulfillment of the requirements for the degree of Master in Computer ScienceThe use of ontologies is nowadays a sufficiently mature and solid field of work to be considered an efficient alternative in knowledge representation. With the crescent growth of the Semantic Web, it is expectable that this alternative tends to emerge even more in the near future. In the context of a collaboration established between FCT-UNL and the R&D department of a national software company, a new solution entitled ECC – Enterprise Communications Center was developed. This application provides a solution to manage the communications that enter, leave or are made within an organization, and includes intelligent classification of communications and conceptual search techniques in a communications repository. As specificity may be the key to obtain acceptable results with these processes, the use of ontologies becomes crucial to represent the existing knowledge about the specific domain of an organization. This work allowed us to guarantee a core set of ontologies that have the power of expressing the general context of the communications made in an organization, and of a methodology based upon a series of concrete steps that provides an effective capability of extending the ontologies to any business domain. By applying these steps, the minimization of the conceptualization and setup effort in new organizations and business domains is guaranteed. The adequacy of the core set of ontologies chosen and of the methodology specified is demonstrated in this thesis by its effective application to a real case-study, which allowed us to work with the different types of sources considered in the methodology and the activities that support its construction and evolution

Validation Framework for RDF-based Constraint Languages

In this thesis, a validation framework is introduced that enables to consistently execute RDF-based constraint languages on RDF data and to formulate constraints of any type. The framework reduces the representation of constraints to the absolute minimum, is based on formal logics, consists of a small lightweight vocabulary, and ensures consistency regarding validation results and enables constraint transformations for each constraint type across RDF-based constraint languages

Ontology Localization

Nuestra meta principal en esta tesis es proponer una solución para construir una ontología multilingüe, a través de la localización automática de una ontología. La noción de localización viene del área de Desarrollo de Software que hace referencia a la adaptación de un producto de software a un ambiente no nativo. En la Ingeniería Ontológica, la localización de ontologías podría ser considerada como un subtipo de la localización de software en el cual el producto es un modelo compartido de un dominio particular, por ejemplo, una ontología, a ser usada por una cierta aplicación. En concreto, nuestro trabajo introduce una nueva propuesta para el problema de multilingüismo, describiendo los métodos, técnicas y herramientas para la localización de recursos ontológicos y cómo el multilingüismo puede ser representado en las ontologías. No es la meta de este trabajo apoyar una única propuesta para la localización de ontologías, sino más bien mostrar la variedad de métodos y técnicas que pueden ser readaptadas de otras áreas de conocimiento para reducir el costo y esfuerzo que significa enriquecer una ontología con información multilingüe. Estamos convencidos de que no hay un único método para la localización de ontologías. Sin embargo, nos concentramos en soluciones automáticas para la localización de estos recursos. La propuesta presentada en esta tesis provee una cobertura global de la actividad de localización para los profesionales ontológicos. En particular, este trabajo ofrece una explicación formal de nuestro proceso general de localización, definiendo las entradas, salidas, y los principales pasos identificados. Además, en la propuesta consideramos algunas dimensiones para localizar una ontología. Estas dimensiones nos permiten establecer una clasificación de técnicas de traducción basadas en métodos tomados de la disciplina de traducción por máquina. Para facilitar el análisis de estas técnicas de traducción, introducimos una estructura de evaluación que cubre sus aspectos principales. Finalmente, ofrecemos una vista intuitiva de todo el ciclo de vida de la localización de ontologías y esbozamos nuestro acercamiento para la definición de una arquitectura de sistema que soporte esta actividad. El modelo propuesto comprende los componentes del sistema, las propiedades visibles de esos componentes, las relaciones entre ellos, y provee además, una base desde la cual sistemas de localización de ontologías pueden ser desarrollados. Las principales contribuciones de este trabajo se resumen como sigue: - Una caracterización y definición de los problemas de localización de ontologías, basado en problemas encontrados en áreas relacionadas. La caracterización propuesta tiene en cuenta tres problemas diferentes de la localización: traducción, gestión de la información, y representación de la información multilingüe. - Una metodología prescriptiva para soportar la actividad de localización de ontologías, basada en las metodologías de localización usadas en Ingeniería del Software e Ingeniería del Conocimiento, tan general como es posible, tal que ésta pueda cubrir un amplio rango de escenarios. - Una clasificación de las técnicas de localización de ontologías, que puede servir para comparar (analíticamente) diferentes sistemas de localización de ontologías, así como también para diseñar nuevos sistemas, tomando ventaja de las soluciones del estado del arte. - Un método integrado para construir sistemas de localización de ontologías en un entorno distribuido y colaborativo, que tenga en cuenta los métodos y técnicas más apropiadas, dependiendo de: i) el dominio de la ontología a ser localizada, y ii) la cantidad de información lingüística requerida para la ontología final. - Un componente modular para soportar el almacenamiento de la información multilingüe asociada a cada término de la ontología. Nuestra propuesta sigue la tendencia actual en la integración de la información multilingüe en las ontologías que sugiere que el conocimiento de la ontología y la información lingüística (multilingüe) estén separados y sean independientes. - Un modelo basado en flujos de trabajo colaborativos para la representación del proceso normalmente seguido en diferentes organizaciones, para coordinar la actividad de localización en diferentes lenguajes naturales. - Una infraestructura integrada implementada dentro del NeOn Toolkit por medio de un conjunto de plug-ins y extensiones que soporten el proceso colaborativo de localización de ontologías

Methods for Matching of Linked Open Social Science Data

In recent years, the concept of Linked Open Data (LOD), has gained popularity and acceptance across various communities and domains. Science politics and organizations claim that the potential of semantic technologies and data exposed in this manner may support and enhance research processes and infrastructures providing research information and services. In this thesis, we investigate whether these expectations can be met in the domain of the social sciences. In particular, we analyse and develop methods for matching social scientific data that is published as Linked Data, which we introduce as Linked Open Social Science Data. Based on expert interviews and a prototype application, we investigate the current consumption of LOD in the social sciences and its requirements. Following these insights, we first focus on the complete publication of Linked Open Social Science Data by extending and developing domain-specific ontologies for representing research communities, research data and thesauri. In the second part, methods for matching Linked Open Social Science Data are developed that address particular patterns and characteristics of the data typically used in social research. The results of this work contribute towards enabling a meaningful application of Linked Data in a scientific domain

Semantic Interoperability in Digital Library Systems

This report is a state-of-the-art overview of activities and research being undertaken in areas relating to semantic interoperability in digital library systems. It has been undertaken as part of the cluster activity of WP5: Knowledge Extraction and Semantic Interoperability (KESI). The authors and contributors draw on the research expertise and experience of a number of organisations (UKOLN, ICS-FORTH, NETLAB, TUC-MUSIC, University of Glamorgan) as well as several work-packages (WP5: Knowledge Extraction and Semantic Interoperability; WP3: Audio-Visual and Non-traditional Objects) within the DELOS2 NoE. In addition, a workshop was held [KESI Workshop Sept. 2004] (co-located with ECDL 2004) in order to provide a forum for the discussion of issues relevant to the topic of this report. We are grateful to those who participated in the forum and for their valuable comments, which have helped to shape this report. Definitions of interoperability, syntactic interoperability and semantic interoperability are presented noting that semantic interoperability is very much about matching concepts as a basis. The NSF Post Digital Libraries Futures Workshop: Wave of the Future [NSF Workshop] has identified semantic interoperability as being of primary importance in digital library research

Semantic annotation of digital music

AbstractIn recent times, digital music items on the internet have been evolving in a vast information space where consumers try to find/locate the piece of music of their choice by means of search engines. The current trend of searching for music by means of music consumersʼ keywords/tags is unable to provide satisfactory search results. It is argued that search and retrieval of music can be significantly improved provided end-usersʼ tags are associated with semantic information in terms of acoustic metadata – the latter being easy to extract automatically from digital music items. This paper presents a lightweight ontology that will enable music producers to annotate music against MPEG-7 description (with its acoustic metadata) and the generated annotation may in turn be used to deliver meaningful search results. Several potential multimedia ontologies have been explored and a music annotation ontology, named mpeg-7Music, has been designed so that it can be used as a backbone for annotating music items

Semantic linking of complex properties, monitoring processes and facilities in web-based representations of the environment

Where a virtual representation of the Earth must contain data values observed within the physical Earth system, data models are required that allow the integration of data across the silos of various Earth and environmental sciences domains. Creating a mapping between the well-defined terminologies of these silos is a stubborn problem. This paper presents a generalised ontology for use within Web 3.0 services, which builds on European Commission spatial data infrastructure models. The presented ontology acknowledges that there are many complexities to the description of environmental properties which can be observed within the physical Earth system. The ontology is shown to be flexible and robust enough to describe concepts drawn from a range of Earth science disciplines, including ecology, geochemistry, hydrology and oceanography. This paper also demonstrates the alignment and compatibility of the ontology with existing systems and shows applications in which the ontology may be deployed

A model for information retrieval driven by conceptual spaces

A retrieval model describes the transformation of a query into a set of documents. The question is: what drives this transformation? For semantic information retrieval type of models this transformation is driven by the content and structure of the semantic models. In this case, Knowledge Organization Systems (KOSs) are the semantic models that encode the meaning employed for monolingual and cross-language retrieval. The focus of this research is the relationship between these meanings’ representations and their role and potential in augmenting existing retrieval models effectiveness. The proposed approach is unique in explicitly interpreting a semantic reference as a pointer to a concept in the semantic model that activates all its linked neighboring concepts. It is in fact the formalization of the information retrieval model and the integration of knowledge resources from the Linguistic Linked Open Data cloud that is distinctive from other approaches. The preprocessing of the semantic model using Formal Concept Analysis enables the extraction of conceptual spaces (formal contexts)that are based on sub-graphs from the original structure of the semantic model. The types of conceptual spaces built in this case are limited by the KOSs structural relations relevant to retrieval: exact match, broader, narrower, and related. They capture the definitional and relational aspects of the concepts in the semantic model. Also, each formal context is assigned an operational role in the flow of processes of the retrieval system enabling a clear path towards the implementations of monolingual and cross-lingual systems. By following this model’s theoretical description in constructing a retrieval system, evaluation results have shown statistically significant results in both monolingual and bilingual settings when no methods for query expansion were used. The test suite was run on the Cross-Language Evaluation Forum Domain Specific 2004-2006 collection with additional extensions to match the specifics of this model