Roland Billen

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Current spatial database systems offer limited querying capabilities beyond binary topological relations. This paper introduces a model for projective relations between regions to support other qualitative spatial queries. The relations are ternary because they are based on the collinearity invariant of three points under projective geometry. The model is(More)
A unique characteristic of GIS as compared to other information systems, is their capacity to manage spatial relationships, such as connections or interrelations among objects in the geometric domain. A number of frameworks use topology as a basic mechanism to define spatial relationships. The OpenGIS consortium has adopted one of them, i.e. the(More)
Although intensive work has been devoted to spatio-temporal qualitative reasoning models, some issues such as management of complex objects life and motion remain. In this paper, we propose a model dealing with existence and presence of object concepts. First, we introduce spatio-temporal states, which express existing spatio-temporal relationships between(More)
Geographical Information Systems demonstrated their utility in numerous archeological studies. However, such systems do not encompass all the characteristics of the archaeological data. Following an interdisciplinary approach, the Geomatics Unit (University of Liege) develops a robust, flexible and dynamic Archeological Information System. This research(More)
This paper contains some reflections about using 3D topology, and more generally some 3D concepts related to 3D cadastre. Firstly, we develop some conceptual views about 3D modelling and more specifically about the definition of 3D spatial objects. Secondly, we present a new framework for representing spatial relationships. The framework has different(More)
Collinearity is a basic arrangement of regions in the plane. We investigate the semantics of collinearity in various possible meanings for three regions and we combine these concepts to obtain definitions for four and more regions. The aim of the paper is to support the formalization of projective properties for modelling geographic information and(More)
This paper presents a model for positional relations among bodies of arbitrary shape in three dimensions. It is based on an existing model for projective relations among regions in two dimensions. The motivation is to provide a formal qualitative spatial relations model for emerging 3D applications. Two sets of relations are defined: ternary projective(More)
This paper introduces a reasoning system based on a previously developed model for ternary projective relations between spatial objects. The model applies to spatial objects of the kind point and region is based on basic projective invariants and takes into account the size and shape of the three objects that are involved in a relation. The reasoning system(More)
Since 1907, the University of Liège houses, among its Art Collection, a scale model representing the city of Liège in the 1730s. Due to the conservation and preservation conditions, the access to this masterpiece has long been restricted. In 2009, the Virtual Leodium Project set up to promote access to a larger public and assuring the conservation of the(More)