Debra F. Laefer

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Traditional documentation capabilities of laser scanning technology can be further exploited for urban modelling through the transformation of resulting point clouds into solid models compatible for computational analysis. This paper introduces such a technique through the combination of an angle criterion and voxelization. As part of that, a k-nearest(More)
In recent years, three-dimensional (3D) data has become increasingly available, in part as a result of significant technological progresses in Light Detection and Ranging (LiDAR). LiDAR provides longitude and latitude information delivered in conjunction with a GPS device, and elevation information generated by a pulse or phase laser scanner, which together(More)
Urban modelling applications require high-precision geometric models both for graphical rendering and for engineering purposes. While geometric models, photographic images and laser-scanned point clouds are ideally co-registered to national coordinate grids at the time of acquisition, the quantity and diversity of data sources means that registration must(More)
A spatial information system (SIS) is critical to the hosting, querying, and analyzing of spatial data sets. The increasing availability of three-dimensional (3D) data (e.g. from aerial and terrestrial laser scanning) and the desire to use such data in large geo-spatial platforms have been dual drivers in the evolution of integrated SISs. Within this(More)
Heightened demand for larger and more accurate microclimate models for heat transfer, pollution accumulation, and wind level prediction has posed new challenges for researchers working in wind tunnels, as well as those employing computational fluid dynamics modeling. Namely, the problem is how to generate geometrically accurate and up to date models(More)
Risk assessment procedures for underground projects form a key component of pre-construction efforts since resulting ground movements may cause damage to adjacent structures. Particularly for urban tunnelling works, surface settlements may impinge on a vast number of structures and can result in significant lawsuits unless the appropriate building(More)