Former Projects

Analysis and Conflation of Road Networks in Digital Maps for Automotive Applications

Contact: Andreas, Hacklöer

A joint effort with BMW Research and Technology, this project investigates methods for the analysis and conflation of road networks. Modern car navigation services rely on vector-oriented road models embedded in digital maps. In order to identify a given road network structure across multiple maps, a matching and conflation process is required which determines a projection from one road network to another, thereby providing a map-agnostic means of identifying geographical references to entities describing road networks. In the project, we develop, investigate and evaluate road network matching techniques for digital vector maps which analyze geometrical, topological and semantic information to derive assignments between road networks on several abstraction levels, ranging from point-to-point correspondencies to structural high-level matchings. The resulting algorithms represent an enabling technology for comparison, fusion, attribute transfer and quality evaluation of digital maps.

Spatial Optimization of Railway Infrastructure Maintenance for Travel Time Saving

Contact: Jian Yang

In this ongoing project, we study the problem by how can we reduce minute-level running time of passenger trains on a given railway route through maintenance instead of costly construction work like changing the existing railway alignment. This interdisciplinary project leverages the expertise not only from cartography but also from railway infrastructure construction, transportation planning and computer science. So far, we’ve established a five-step semi-automated process including data preprocessing, timesaving potential estimation, maintenance site selection, site inspection and planning result reporting and also developed a prototype program tool based on our method to facilitate decision makers on maintenance planning.

Comparative study of thematic mapping and scientific visualization

Contact: Linfang, Ding

Visualization of 4-D Building Deformation from High-resolution SAR Data — The project is dedicated to visualize 4-D space-time building deformation datasets retrieved from high resolution satellite SAR images, which are crucial to monitor building behavior as well as detect potential damages in urban areas. Based on the data characteristics, appropriate design methods and visualization techniques should be identified from disciplines like scientific visualization and thematic mapping, which may allow users to explore detailed deformation information as well as to perceive the overall building deformation patterns immediately.

Lightning data analysis

Contact: Stefan, Peters

This research project  focus on the visual analysis of lightning data. Starting point are 3D coordinates and the exact occurrence time of lightning data. In a first step lightning cells are identified and tracked. Then an interactive graphic user interface is developed to investigate the dynamics of the lightning cells: e.g. changes of cell density, location, extension as well as merging and splitting in 3D over time. Furthermore a statistical analysis is provided. The second part of this research contains a short term forecasting of lightning cells and the visualization of its uncertainty. The visual exploring tools are investigated for two determined user groups: lightning experts and interested lay public.

Multi-dimensional visualization of spatio-temporal data

Contact: Christian Murphy

Space-Time Mapping of Mass Event Data ­­— To simultaneously visualize thematic data in space and time a third dimension must be added. In this work conventional cartographic symbolization meets the space-time cube to create a holistic three dimensional spatio-temporal visualisation model. The two dimensional proportional symbol mapping technique is adopted and extruded into the third dimension to model the temporal factor. Kernel density estimation is performed on the time line to create a temporal continuous model from discrete points in time. The resulting visualization model is implemented into an earth viewer to enable the user to freely navigate and animate the phenomenon and visually detect spatio-temporal anomalies without losing the overall view. This tool is evaluated by visualizing the events of a mobile phone location dataset over space and time in one single model.

Multi-dimensional visualization of spatio-temporal data

Contact: Mathias Jahnke

To support experts as well as non-experts in their decisions is one main goal of the geospatial domain. The non-photorealistic visualization offers a new way of a user oriented cartographic communication on small mobile displays. In particular 3D city models presentations can profit from this approach because most of the city model visualizations do not tap the full potential of a combined geometric, semantic information presentation. The non-photorealistic approach of abstracted information reduced visualization seems to be feasible for a combination with cartographic design concepts and offers more degrees of freedom to add semantic information particularly on small mobile devices. To reach this goal on one hand the theories and method from traditional 2D cartography have to be expanded for the usage in the third dimension on the other hand the user have to be taken into account. The user is of main interest when developing new visualization styles because he is the only person who can give valid feedback about the usability of such new visualization styles.

2D and 3D Thermal facade data visualization

Contact: Holger Kumke

The project is dedicated to the visual enrichment of thermal data on building facades in urban area. Heat radiation or thermogram which can be detected and measured by physical instruments shows invisible thermal information and indicates the state of the building surface. It serves as raw data for the design of thermal façade maps on planar display surface as well as 3D space-based map-related depictions. Similar to the digital thematic map design, the thermal maps are conceived for the output on screens. Their special characteristics, however, have opened up many innovative visualization alternatives.

Location-Based Services & indoor navigation

Contact person: Jukka Krisp

Location-Based Services (LBS) are investigated from different perspectives that include mobile positioning and tracking technologies, data capturing and computing devices, integrated software engineering, user studies for various applications. The enabling sensory technologies and interactive open-source platforms are continuously changing the way of our thinking and living and reshaping the research scope of LBS. LBS is an integrative discipline that unites research ideas from related fields. Technical challenges still occur on the indoor navigation data acquisition, the path computation and the communication of a potential indoor path to the user.

A Congruent Hybrid Model for Conflation of Geo-Referenced Image and Road Network

Contact person: Jiantong Zhang  

In the project, we investigate a novel Congruent Hybrid Model(CHM) to rectify the misalignments between road vectors and geo-referenced images. The matching cost between the extracted road centerlines and the prior road network was optimized using Sparse Matching Algorithm (SMA) to get the optimal correspondence, and then the road segments were transformed to its partner using two frequently transformation functions — the piecewise Rubber-Sheeting (RUB) approach and the Thin Plate Splines (TPS) approach. The experiments with synthesized data as well as the real spatial data sets have verified the efficiency of CHM. The snake-based approach is a natural subsequence of the presented model. However, the CHM can be also directly employed for geospatial visualization applications