Laure SALIGNY / Xavier RODIER
(CNRS France)

Keywords: Urban transformation, temporal dimension, chronographie, Python language

Abstract:
The study of the urban fabric and the spatial dynamics of urban space is based on an understanding of the city as a complex system composed of individual historical objects. The OH_FET model which we developed since 2004, is based on this approach of urban space. It describes the historical urban object as the Cartesian product of three basic dimensions: function (social use), space and time from the works of Donna Peuquet in geomatics and James Allen in artificial intelligence. Although the heuristic potential of the model have already been proven to work on the cities of Tours and , more recently, Vendome in France, the integration constraints, the designing and data manipulation imposed by the model were too much complicated with the software available to allow the broadcasting of its use.
With support from the European Regional Development Fund (ERDF) and the Burgundy region, we have developed an application in Python programming language, connected to a spatial database (SpatiaLite or PostGre/GIS). This application consists of different modules. The first module allows to manage automatically the designing of spatial and temporal features like Historical Objects component, within the constraints of OH_FET model. The second module products on one hand some analyzes of urban transformations, on the other hand visualizations about the temporal dimension (chronographies). The treatment of the temporal dimension are display by graphs concerning, for example, the functional transformation of urban space in time.
The case studies have so far focused on the transformation of districs or small towns. The further development of the application will focus on the treatment of the temporal dimension from relative chronologies across the excavation scale for which experimental work has shown the relevance of the model.