An Information System for Urban Spatial Analysis using Digital Catography M. K. Kholladi and M. C. Batouche Equipe PRAI, Institut d'Informatique, University of Constantine, Route de Ain El-Bey, Constantine 25000, Algeria. Tel & Fax : 213 4 92 28 35 / 213 4 92 51 20 Abstract Many research works in automated cartography are carried out to solve problems related to social and urban human needs. In this paper, an information system for urban spatial analysis is presented. The proposed system outlines a method for urban spatial representing, modelling and reasoning that provide valuable intelligent aids for sorting out different spatial problems such land use planning, environmental assessment and demo-socio-economic analysis. Thus, the proposed system would be a major contribution for solving difficulties frequently encountered by large users in urban agencies. KEY WORDS : Spatial queries, spatial reasoning, urban spatial analysis, R-tree representation, computational geometry and database systems. 1. Introduction During the last decade, a considerable attention has been devoted to the problem of analysing and interpreting digital cartography [ARO 89, MUE 86, BER 87, TOM 90, LAU 92], where spatial aspect is privileged. Therefore, the main concern here is with concepts, principles and ways of organising and reasoning about spatial information [LAU 89, RIA 94]. Spatial knowledge manipulation involves many concepts which insight multiple reasoning methods and shows how their unification in a single model, which could be applied to several cases, is very difficult. These difficulties are mainly due to the nature of spatial objects and their properties related to semantic, geometric and topological aspects. Consequently, designing an autonomous urban spatial information system is not an easy task and further research work for spatial modelling and reasoning is necessary [LAU 92]. In this paper, an information system for urban spatial analysis is presented. The system uses computational geometry based rules for solving spatial and non spatial urban queries. To solve spatial queries, the topological aspect related to urban hierarchy is implemented using Rectangle-Tree (R-Tree) model. Data associated with the semantic of cartographic urban objects is structured into a database. The remaining of the paper is organised as follows: section 2 describes the need for an urban information system. Design issues of such a system are discussed in section 3. In section 4, the representation and modelling schemes for urban objects are presented. Both spatial and non