Answering queries in the presence of XML keys

Proceedings - International Workshop on Database and Expert Systems Applications, DEXA476-48

Data and Quality Integration in GIS

International audienceDecision making often relies on digital geographic data. These decisions are sometimes very important, and their consequences may be very costly. On one hand, any decision is affected by the quality of the data, and, in spite of the information about data quality, which is provided in metadata by the Mapping Agencies, almost nobody uses it. The reason is identified - a viewpoint mismatch - but no solution has been elaborated to date. On the other hand, there is a need to integrate several data sources with multiple definitions organized in different schemas, which match imperfectly and whose data quality can be very heterogeneous. The work described in this paper aims to provide a data integration approach that copes with quality information. The problem consists on integrating different heterogeneous and autonomous geographic data sources having different qualities. Our goal is to define a mediation approach in order to integrate not only the data sources but also the tools (programs) that manipulate them as well as their qualities. The originality of this work consists on a new way of resolving the problem of data integration with taking account of the quality information and tools, notably quality processing ones

Data and Quality Integration in GIS

International audienceDecision making often relies on digital geographic data. These decisions are sometimes very important, and their consequences may be very costly. On one hand, any decision is affected by the quality of the data, and, in spite of the information about data quality, which is provided in metadata by the Mapping Agencies, almost nobody uses it. The reason is identified - a viewpoint mismatch - but no solution has been elaborated to date. On the other hand, there is a need to integrate several data sources with multiple definitions organized in different schemas, which match imperfectly and whose data quality can be very heterogeneous. The work described in this paper aims to provide a data integration approach that copes with quality information. The problem consists on integrating different heterogeneous and autonomous geographic data sources having different qualities. Our goal is to define a mediation approach in order to integrate not only the data sources but also the tools (programs) that manipulate them as well as their qualities. The originality of this work consists on a new way of resolving the problem of data integration with taking account of the quality information and tools, notably quality processing ones

Une approche spatio-multidimensionnelle pour l’analyse des aléas environnementaux

National audienceLes entrepôts de données spatiales et les systèmes SOLAP permettent l’analyse en ligne de gros volumes de données géo-référencées. Dans un contexte de gestion des risques naturels, ces systèmes ont été utilisés avec succès sur des données officielles dont la collecte suit un processus bien établi. Le développement récent d’outils collaboratifs pour la saisie de données géographiques, y compris par des utilisateurs non-experts a engendré un nouveau concept : celui de l’Information Géographique Volontaires (VGI), et a créé un besoin et une opportunité pour prendre en compte ces données dans un processus décisionnel. Dans cet article, nous décrivons un modèle et un système spatio-multidimensionnel permettant l’utilisation conjointe des données VGI avec des systèmes SOLAP pour l’analyse des aléas environnementaux

Une approche spatio-multidimensionnelle pour l’analyse des aléas environnementaux

National audienceLes entrepôts de données spatiales et les systèmes SOLAP permettent l’analyse en ligne de gros volumes de données géo-référencées. Dans un contexte de gestion des risques naturels, ces systèmes ont été utilisés avec succès sur des données officielles dont la collecte suit un processus bien établi. Le développement récent d’outils collaboratifs pour la saisie de données géographiques, y compris par des utilisateurs non-experts a engendré un nouveau concept : celui de l’Information Géographique Volontaires (VGI), et a créé un besoin et une opportunité pour prendre en compte ces données dans un processus décisionnel. Dans cet article, nous décrivons un modèle et un système patiomultidimensionnel permettant l’utilisation conjointe des données VGI avec des systèmes SOLAP pour l’analyse des aléas environnementaux

De l'information géographique volontaire à l'OLAP géographique volontaire : une approche basée sur la qualité

International audienceVolunteered Geographic Information (VGI) represents a valuable source of information. At the same time this data presents new data quality issues such as credibility. In this paper, we investigate the integration of VGI in Spatial OLAP (SOLAP) systems, which allow analyzing huge volume of geographic datasets. By means of a real case study, we highlight the similarities and differences of these two kinds of systems. We propose a methodology to handle VGI data quality issues during the warehousing and OLAPing phases. In particular, we define a new aggregation ETL operator based on the VGI credibility. We also present a spatio-multidimensional model that provides decision-makers with a general description of the correctness of the SOLAP aggregations

Un modèle générique Spatial OLAP pour l'évaluation des risques naturels dans un contexte volontaire d'information géographique

International audienceSpatial data warehouses (SDW) and spatial OLAP (SOLAP) systems are well-known business intelligence technologies that aim to support a multidimensional and online analysis for a large volume of geo-referenced datasets. SOLAP systems are already used in the context of natural hazards for analyzing sensor data and experts’ measurements. Recently, new data gathering tools coined as volunteered geographic information systems (VGI) have been adopted especially by non-expert users. Hence, (spatial) application development is facing a new challenge, which is the integration of expert-oriented data with citizen-provided data. In this paper, we propose a new generic spatio-multidimensional model based on the question/answer risk evaluation model that allows the integration of VGI data with classical SDW and SOLAP systems for the online analysis of natural hazards monitored by volunteers

De l'information géographique volontaire à l'OLAP géographique volontaire : une approche basée sur la qualité

International audienceVolunteered Geographic Information (VGI) represents a valuable source of information. At the same time this data presents new data quality issues such as credibility. In this paper, we investigate the integration of VGI in Spatial OLAP (SOLAP) systems, which allow analyzing huge volume of geographic datasets. By means of a real case study, we highlight the similarities and differences of these two kinds of systems. We propose a methodology to handle VGI data quality issues during the warehousing and OLAPing phases. In particular, we define a new aggregation ETL operator based on the VGI credibility. We also present a spatio-multidimensional model that provides decision-makers with a general description of the correctness of the SOLAP aggregations