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WEDNESDAY, September 6
13.50 - 14.00	Welcome
14.00 - 15.00	KEYNOTE TALK: Michael Worboys, Keele University, United Kingdom  Imperfect Geospatial Data Handling The title is intended to mean that the data is imperfect rather than the handling, although the latter usually follows from the former. Information gained from observations of the world is 'imperfect' is so far as it is dependent upon factors such as limitations of measuring devices, accessibility of parts of the world to observation, and human fallibility. Geographic information systems, at least those outside the research environment, are only capable of modelling, managing and manipulating 'perfect' spatial data, with the assumption that the information on which the data are based is accurate and precise, and that information sets are coherent and sufficient to support the application requirements. The presentation will survey approaches to spatial data handling that explicitly recognize their imperfection. We begin with a classification of forms of imperfection in the context of geospatial phenomena. The classification is based on the inconsistency -incompleteness dichotomy, common in logic. Inconsistency results from inaccurate observations, and is the internal contradiction of propositions derivable from the data set. Incompleteness is the inability of the information set to answer the questions required of it by the application(s). An important manifestation of incompleteness is imprecision, where constraints on the observation device or otherwise result in an under-specification in information about the phenomenon, relative to the application requirement. A subclass of imprecision is vagueness, where there exist borderline cases in the specification of the concept. Many (most) geospatial concepts are vague: 'urban area', 'hill', 'south of England', and 'large town' provide the beginning of an unending list of examples. We will survey some of the approaches to inconsistency handling and the related issue of revision of a spatial knowledge base on receipt of new information that contradicts the status quo. Approaches to imprecision and vagueness are also discussed in the context of geospatial information handling. The presentation will provide a mid-term report work on the 'VUG' (Vagueness, uncertainty and granularity) project, funded by the UK Engineering and Physical Sciences Research Council as well as describing early results on the EU funded REVIGIS project.
15.00 - 15.15	Coffee break
15.15 - 16.45	SESSION 1: DATA MODELS S. Cicerone, D. Frigioni, P. Di Felice Decomposing Spatial Databases with Applications S. Cicerone, D. Frigioni, L. Tarantino Interacting with Geographic Databases: A Focus+Context Approach
16.45 - 17.00	Coffee break
17.00 - 18.30	SESSION 2: SPATIAL REASONING R. K. Goyal, M. J. Egenhofer Consistent Queries over Cardinal Directions across Different Levels of Detail S. Zlatanova On 3D Topological Relations
THURSDAY, September 7
09.00 - 10.00	KEYNOTE TALK: Norman Paton, University of Manchester, United Kingdom  Spatio-Temporal Databases: Contentions, Components and Consolidation (with the coauthors Alvaro A.A. Fernandes and Tony Griffiths) Spatio-temporal databases have been the focus of considerable research activity over a significant period. However, there are as of yet very few prototypes of complete systems, far less products that provide effective support for applications tracking changes to spatial and aspatial data over time. We contend that this is because much of the activity in spatio-temporal databases has focused on specific parts of the problem, at the expense of a more holistic view of database systems design and development. It is probably also the case that the database research community has been inclined to undervalue integration or consolidation activities. This paper outlines some contentions relating to spatio-temporal databases, with a view to pruning the space of possible paths that consolidation activities might follow. Suggestions are also made as to what areas are most likely to present challenges to a consolidation activity, in the light of a model architecture for a spatio-temporal database.
10.00 - 10.15	Coffee break
10.15 - 12.30	SESSION 3: SPATIO-TEMPORAL DATA C. Kleiner, U. W. Lipeck Efficient Index Structures for Spatio-Temporal Objects A. Raffaeta, C. Renso Temporal Reasoning in Geographical Information Systems A. Stefanidis, P. Partsinevelos, P. Agouris, P. Doucette Summarizing Video Datasets in the Spatiotemporal Domain
12.30 - 14.00	Lunch
14.00 - 16.15	SESSION 4: INDEX STRUCTURES A. A. B. Lima, C. Esperanca, M. Mattoso A Parallel Spatial Join Framework Using PMR Quadtrees P. Magillo, V. Bertocci Managing Large Terrain Data Sets with a Multiresolution Structure A. AL-Badarneh, F. Fotouhi The SBS: an Efficient Index Structure for Spatial Database Applications