A new face-entity concept for modeling urban morphology

The modeling of a common set of urban land features in a topological structure useful for a range of applications, including routine operations and decision-making, is described in this paper. This collection of non-redundant shareable data is based on an identification of administrative agencies that would use and/or manage these data. Using this information, an object-based conceptual model is developed that employs the face-and-entity concept to account for all basic land units and organizes them into different levels of hierarchy. This structuring is based on physical containment (e.g., building and pavement entities are wholly contained in the block entity, resulting in two levels of faces) and urban management rules (i.e., each face and/or its entities are uniquely managed by a certain authority). The derived conceptual model, including both the meta data and the geometry associated with the face hierarchy, is formalized with EXPRESS, an object-oriented data description language that conforms to universal and regional geographical information system (GIS) terminology and standards.