Showing papers by "Frederico T. Fonseca published in 2002"

Using Ontologies for Integrated Geographic Information Systems

Abstract: Today, there is a huge amount of data gathered about the Earth, not only from new spatial information systems, but also from new and more sophisticated data collection technologies. This scenario leads to a number of interesting research challenges, such as how to integrate geographic information of different kinds. The basic motivation of this paper is to introduce a GIS architecture that can enable geographic information integration in a seamless and flexible way based on its semantic value and regardless of its representation. The proposed solution is an ontology-driven geographic information system that acts as a system integrator. In this system, an ontology is a component, such as the database, cooperating to fulfill the system’s objectives. By browsing through ontologies the users can be provided with information about the embedded knowledge of the system. Special emphasis is given to the case of remote sensing systems and geographic information systems. The levels of ontologies can be used to guide processes for the extraction of more general or more detailed information. The use of multiple ontologies allows the extraction of information in different stages of classification. The semantic integration of aerial images and GIS is a crucial step towards better geospatial modeling.

Semantic Granularity in Ontology-Driven Geographic Information Systems

Abstract: The integration of information of different kinds, such as spatial and alphanumeric at different levels of detail, is a challenge. While a solution is not reached, it is widely recognized that the need to integrate information is so pressing that it does not matter if detail is lost, as long as integration is achieved. This paper shows the potential for information retrieval at different levels of granularity inside the framework of information systems based on ontologies. Ontologies are theories that use a specific vocabulary to describe entities, classes, properties and functions related to a certain view of the world. The use of an ontology, translated into an active information system component, leads to ontology-driven information systems and, in the specific case of GIS, leads to what we call ontology-driven geographic information systems.

From Geo- to Eco-ontologies

Abstract: Ecology is a subject of great debate today among scientists, governments, and the general public. Issues such as global warming and biodiversity require a mutual agreement among different groups of people. Many times these groups are separated by language, political interests, and culture. Environmental Information Systems need to integrate data from different Geographic Information Systems. This may cause problems resulting from the semantic heterogeneity of the source communities. Before this kind of integration can happen among different groups, the concepts that people have about the real world must be explicitly formalized; such an explicit formalization of our mental models is called an ontology. In this paper we discuss two options for structuring such ontologies. First we discuss the use of hierarchies and roles in the structure of geographic ontologies. Second, we discuss some of the fundamental characteristics of ecological ontologies and draw attention to several formal differences between ecological and geographic ontologies. We conclude by identifying some of the important questions that arise in light of our conception of eco-ontologies.

Research Article Using Ontologies for Integrated Geographic Information Systems

Abstract: Today, there is a huge amount of data gathered about the Earth, not only from new spatial information systems, but also from new and more sophisticated data collection technologies. This scenario leads to a number of interesting research challenges, such as how to integrate geographic information of different kinds. The basic motivation of this paper is to introduce a GIS architecture that can enable geographic information integration in a seamless and flexible way based on its semantic value and regardless of its representation. The proposed solution is an ontology-driven geographic information system that acts as a system integrator. In this system, an ontology is a component, such as the database, cooperating to fulfill the system’s objectives. By browsing through ontologies the users can be provided with information about the embedded knowledge of the system. Special emphasis is given to the case of remote sensing systems and geographic information systems. The levels of ontologies can be used to guide processes for the extraction of more general or more detailed information. The use of multiple ontologies allows the extraction of information in different stages of classification.