Topologically consistent 3D city models obtained by extrusion

One of the simplest methods to construct a 3D city model is to extrude building footprints to obtain \block-shaped" polyhedra representing buildings. While the method is well-known and easy to implement, if the 2D topological relationships between the footprints are not taken into account, the resulting 3D city models will not necessarily be...

Modelling and analysing 3D buildings with a primal/dual data structure

While CityGML permits us to represent 3D city models, its use for applications where spatial analysis and/or real-time modifications are required is limited since at this moment the possibility to store topological relationships between the elements is rather limited and often not exploited. We present in this paper a new topological data...

Transportation mode-based segmentation and classification of movement trajectories

The knowledge of the transportation mode used by humans (e. g. bicycle, on foot, car, and train) is critical for travel behaviour research, transport planning and traffic management. Nowadays, new technologies such as the GPS have replaced traditional survey methods (paper diaries, telephone) since they are more accurate and problems such as...

Generation and Dissemination of a National Virtual 3D City and Landscape Model for the Netherlands

This paper describes the generation and dissemination of a national three-dimensional (3D) dataset representing the virtual and landscape model. The 3D model is produced automatically by fusing a two-dimensional (2D) national objectoriented database describing the physical landscape and the national high-resolution height model of the...

On the validation of solids represented with the international standards for geographic information

The international standards for geographic information provide unambiguous definitions of geometric primitives, with the aim of fostering exchange and interoperability in the geographical information system (GIS) community. In two dimensions, the standards are wellaccepted and there are algorithms (and implementations of these) to validate...