Edgar Butwilowski

Modelling and Managing Topology in 3D Geoinformation Systems

Modelling and managing topology in 3D GIS is a non-trivial task. The traditional approaches for modelling topological data in 2D GIS cannot be easily extended into higher dimensions. In fact, the topology of real 3D models is much more complex than that of the 2D and 2.5D models used in classical GIS; in consequence there is a great number of different 3D spatial models ranging from constructive solid geometry to boundary representations. The choice of a particular representation is generally driven by the requirements of a given application. Nevertheless, from a data management point of view, it would be useful to provide a general topological model handling 2D, 2.5D and 3D models in a uniform way. In this paper we describe concepts and the realisation of a general approach to modelling and managing topology in a 3D GIS based on oriented d-Generalised Maps and the closely related cell-tuple structures. As an example of the applicability of the approach, the combination of a group of buildings from a 3D city model with the corresponding part of a 2D city is presented. Finally, an outlook to ongoing research is given in the context of topological abstraction for objects represented in multi-representation databases.

DB4GeO, a 3D/4D Geodatabase and Its Application for the Analysis of Landslides

The analysis and preparation of information are still particularly critical points in the early warning chain of natural hazards. Also there is a strong demand for analyzing geological hazards such as earthquakes, landslides, and tsunamis. Therefore the management of heterogeneous and large sets of geodata may become one of the key issues in early warning and emergency management. Geodatabases may support the analysis of landslides significantly, as the responsible decision makers are usually confronted with huge amounts of original and interpreted data. The 3D/4D geodatabase introduced in this chapter provides efficient geodata retrieval by its service-based architecture which enables an easy-to-use internet-based geodata access . Concepts and implementation issues for the management of spatial and spatiotemporal data are presented. An application scenario for early warning demonstrates the applicability of the proposed approach. Finally a conclusion and an outlook on future research are presented within a distributed software environment for early warning geotools.

Topological and Geometric Data Handling for Time-Dependent Geo-Objects Realized in DB4GeO

In advanced spatio-temporal scenarios, such as the simulation of complex geo-processes, the analysis of complex surface- and volume-based objects changing their locations and shapes in time is a central task. For example, the documentation of landfills, mass movements or volcanic activities requires 4D modeling based on dynamic geometric and topological database structures. In this contribution we present our concepts and implementation efforts for the effective handling of geospatial and time-dependent data realized in DB4GeO, a service-based geo-database architecture. The topological and geometric data models of DB4GeO are described in detail. A geoscientific application of an open-pit mine demonstrates the usefulness of the concepts introduced at the beginning of the paper. Finally, an outlook is given on future geo-database work dealing with extensions of DB4GeO and the handling of geo-objects in the context of cooperative 4D metro tracks planning

Modeling and Managing Topology for 3-D Track Planning Applications

Topology plays a central role in the modelling and management of n-d geo-information. However, hitherto the standardization of n-d topological data models is still at its beginning. A general model based on oriented hierarchical d-Generalised Maps is proposed to handle topology in object-oriented geo-database management systems. The implementation of the approach is demonstrated as module in DB4GeO, our service-oriented 3-d geo-database architecture. A 3-d tracks planning application example in the city of Munich is presented demonstrating the usage of the n-d topological model. Finally, an outlook on our ongoing 3-d geoinfo research in the Dubai region is given.

Temporal and Spatial Database Support for Geothermal Sub-surface Applications

Geothermal energy production from the deep subsurface requires a detailed knowledge of the relevant static and transient parameter distribution in the reservoir and host rock. In reservoir exploration, engineering and operation phases, both temporal and spatial subsurface parameters are acquired, evaluated and monitored in order to improve the reservoir performance. To support temporal and spatial data access to geothermal data sources, an efficient 3D/4D GIS is proposed in this study. We discuss theoretical and first practical approaches for the management of such temporal and spatial geothermal data. A first practical example is provided using the data acquired in the Soultz-sous-Forets geothermal project (France). A distributed software architecture, database design, and the concept for advanced query component with embedded simulations are presented. Finally, we give an outlook on the planned future research in 3D data management of subsurface, near-surface, and above-surface installations in other projects.

3D Geoinformation Science

Nowadays 3D Geoinformation is needed for many planning and analysis tasks. For example, 3D city and infrastructure models are paving the way for complex environmental and noise analyzes. 3D geological sub-surface models are needed for reservoir exploration in the oil-, gas-, and geothermal industry. Thus 3D Geoinformation brings together researchers and practitioners from different fields such as the geo-sciences, civil engineering, 3D city modeling, 3D geological and geophysical modeling, and, last but not least, computer science. The diverse challenges of 3D Geoinformation Science concern new approaches and the development of standards for above- and under-ground 3D modeling, efficient 3D data management, visualization and analysis. Finally, the integration of different 3D approaches and data models is seen as one of the most important challenges to be solved.