Bernhard Höfle

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BACKGROUND Childhood malnutrition is a serious challenge in Sub-Saharan Africa (SSA) and a major underlying cause of death. It is the result of a dynamic and complex interaction between political, social, economic, environmental and other factors. As spatially oriented research has been established in health sciences in recent years, developments in(More)
Airborne laser scanning (ALS) is a remote sensing technique well-suited for 3D vegetation mapping and structure characterization because the emitted laser pulses are able to penetrate small gaps in the vegetation canopy. The backscattered echoes from the foliage, woody vegetation, the terrain, and other objects are detected, leading to a cloud of points.(More)
Terrestrial laser scanning provides a point cloud, but usually also the “intensity” values are available. These values are mainly influenced by the distance from sensor to object and by the object’s reflection properties. We demonstrate that it is possible to retrieve these reflection properties from the observed range and the intensity value. An experiment(More)
In this paper, a new GIS workflow for fully automated building detection from airborne LiDAR data is introduced. The strengths of both raster and point cloud based methods are combined, in order to derive reliable building candidate regions serving as input for 3D building outline extraction and modeling algorithms. Input data are a normalized Digital(More)
A relative height threshold is defined to separate potential roof points from the point cloud, followed by a segmentation of these points into homogeneous areas fulfilling the defined constraints of roof planes. The normal vector of each laser point is an excellent feature to decompose the point cloud into segments describing planar patches. An object-based(More)
In this paper, a new GIS workflow for fully automated urban vegetation and tree parameter extraction from airborne LiDAR data is presented. The strengths of both rasterand point cloud-based methods are combined, in order to derive a vegetation map layer as well as single tree parameters (e.g. tree height and crown width) in an efficient way. The workflow is(More)
As glaciers are good indicators for the regional climate, most of them presently undergo dramatic changes due to climate change. Remote sensing techniques have been widely used to identify glacier surfaces and quantify their change in time. This paper introduces a new method for glacier surface segmentation using solely Airborne Laser Scanning data and(More)
Airborne laser scanning is an evolving operational measurement technique for deriving forest parameters. The objective of the current study was to analyze the potential of full-waveform airborne laser scanning for tree species classification of a mixed woodland. The quantities used were the echo width, backscatter cross section, as well as the distribution(More)
In this study, a semi-empirical model that was originally developed for stem volume estimation is used for aboveground biomass (AGB) estimation of a spruce dominated alpine forest. The reference AGB of the available sample plots is calculated from forest inventory data by means of biomass expansion factors. Furthermore, the semi-empirical model is extended(More)
Airborne LiDAR (Light Detection And Ranging) combines cost efficiency, high degree of automation, high point density of typically 1–10 points per m2 and height accuracy of better than ±15 cm. For all these reasons LiDAR is particularly suitable for deriving precise Digital Terrain Models (DTM) as geometric basis for hydrodynamicnumerical (HN) simulations.(More)