Le travail présenté dans cette thèse aborde la problématique de la personnalisation des analyses OLAP au sein des bases de données multidimensionnelles. Une analyse OLAP est modélisée par un graphe dont les nœuds représentent les contextes d’analyse et les arcs traduisent les opérations de l’utilisateur. Le contexte d’analyse regroupe la requête et le résultat. Il est décrit par un arbre spécifique qui est indépendant des structures de visualisation des données et des langages de requête. Par ailleurs, nous proposons un modèle de préférences utilisateur exprimées sur le schéma multidimensionnel et sur les valeurs. Chaque préférence est associée à un contexte d’analyse particulier. En nous basant sur ces modèles, nous proposons un cadre générique comportant deux mécanismes de personnalisation. Le premier mécanisme est la personnalisation de requête. Il permet d’enrichir la requête utilisateur à l’aide des préférences correspondantes afin de générer un résultat qui satisfait au mieux aux besoins de l’usager. Le deuxième mécanisme de personnalisation est la recommandation de requêtes qui permet d’assister l’utilisateur tout au long de son exploration des données OLAP. Trois scénarios de recommandation sont définis : l’assistance à la formulation de requête, la proposition de la prochaine requête et la suggestion de requêtes alternatives. Ces recommandations sont construites progressivement à l’aide des préférences de l’utilisateur. Afin valider nos différentes contributions, nous avons développé un prototype qui intègre les mécanismes de personnalisation et de recommandation de requête proposés. Nous présentons les résultats d’expérimentations montrant la performance et l’efficacité de nos approches. / This thesis investigates OLAP analyses personalization within multidimensional databases. OLAP analysis is modeled through a graph where nodes represent the analysis contexts and graph edges represent the user operations. The analysis context regroups the user query as well as result. It is well described by a specific tree structure that is independent of the visualization structures of data and query languages. We provided a model for user preferences on the multidimensional schema and values. Each preference is associated with a specific analysis context. Based on previous models, we proposed a generic framework that includes two personalization processes. First process, denoted query personalization, aims to enhancing user query with related preferences in order to produce a new one that generates a personalized result. Second personalization process is query recommendation that allows helping user throughout the OLAP data exploration phase. Our recommendation framework supports three recommendation scenarios, i.e., assisting user in query composition, suggesting the forthcoming query, and suggesting alternative queries. Recommendations are built progressively basing on user preferences. In order to implement our framework, we developed a prototype system that supports query personalization and query recommendation processes. We present experimental results showing the efficiency and the effectiveness of our approaches.

München, Techn. Univ., Diss., 2001. / Computerdatei im Fernzugriff.

München, Techn. University, Diss., 2001.

[pt] O objetivo desta dissertação é apresentar os tópicos relevantes a respeito de SIEs (Sistemas de Informação para Executivos) e desenvolver um sistema para o banco de dados do Programa de Fomento Florestal da Aracruz Celulose, que abrange vários municípios nos estados do Espírito Santo, onde se localiza a empresa, e Minas Gerais. São discutidas neste trabalho as principais definições envolvendo SIEs, o histórico, as principais características e os usuários destes sistemas, as aplicações e os principais softwares envolvendo OLAP (On-Line Analytical Processing). São apresentados também algumas características da Aracruz e de seu programa de fomento. No sistema desenvolvido, foram construídos 11 relatórios que abrangem os principais campos do banco de dados. Os relatórios foram feitos com os recursos do Excel, utilizando Tabelas Dinâmicas, Formulários e Macros para a navegação entre os gráficos e os próprios relatórios. Os relatórios são flexíveis no sentido em que as informações podem ser apresentadas segundo a necessidade do usuário. Os resultados obtidos no trabalho, além de permitirem a extração de informações importantes para o gerenciamento do programa de fomento, conseguem explicitar muitas das características dos SIEs discutidas na Dissertação. / [en] The objective of this dissertation is to introduce some relevant topics of EIS (Executive Information Systems) and develop an EIS for the Aracruz Celulose is Forest Fomentation Program, that includes various cities in the Espirito Santo and Minas Gerais Departments. This work presents the definitions about EIS, their historic, their mains characteristics, the applications and the main software, including OLAP (On-Line Analytical Processing). Furthermore, some characteristics of the Aracruz and its Fomentation Program are introduced. An EIS system has been proposed, composed by eleven reports that embraces the main attributes of the database. These reports were make with the resources of the Excel, using dynamic tables, forms and macros, used for the navigation between the graphics and reports. The reports are flexible, because the information can be visualized according to the necessity of the user. The results obtained in this study allow the extraction of important information for the administration of the Fomentation Program and show various characteristics of the EIS considered in the dissertation.

published_or_final_version / Computer Science / Doctoral / Doctor of Philosophy

Data warehousing and On-line Analytical Processing (OLAP) are powerful tools for processing and analyzing business and analytical data. It is estimated that 80% of the data stored in data warehouses have some spatial components. It is our belief that there is a need for powerful OLAP tools that are capable of processing and analyzing spatial data. This thesis explores the design and implementation of Spatial OLAP (SOLAP) systems and describes approaches to support the characteristic features of OLAP while seamlessly integrating spatial data into the analysis process. In particular, we analyze the evaluation of OLAP queries in the presence of asymmetric, multiple-alternative, generalized, and non-strict spatial dimension hierarchies. We introduce a new pipeline-based query evaluation model that is comprehensive and powerful in that it provides a uniform approach to the expression of spatial OLAP queries that address all major dimension hierarchy types while permitting a uniform treatment of both spatial and non-spatial data. A reference implementation called "LISA" validates the objectives of our model and demonstrates favorable scalability and performance on modern multi-processor and multi-core hardware platforms. We also describe a new "geoCUBE" index, to address the fundamental problem of how to represent, index and efficiently query data that is defined by a mix of spatial and categorical attribute values. The geoCUBE index extends existing methods for indexing OLAP data to spatial data types. The effectiveness of the geoCUBE data structure is confirmed through evaluation. Lastly, we propose algorithms that facilitate OLAP-like analysis of moving object data. We introduce a new class of GROUP BY operators specifically targeted to the OLAP analysis of trajectories and to answering aggregate queries with respect to the spatio-temporal movement of a set of objects. Through an experimental evaluation we show our operators can be used to reliably identify groups of related trajectories when applied to synthetic and real world moving object data.

Zugl.: Berlin, Freie Univ., Diplomarbeit, 2007

Stuttgart, Univ., Studienarbeit, 2001.

Stuttgart, Univ., Diplomarb., 2002.

Konstanz, FH, Diplomarb., 2003.