Concepts for the Representation, Storage, and Retrieval of Spatio-Temporal Objects in 3D/4D Geo-Informations-Systems

The quickly increasing number of spatio-temporal applications in fields like environmental management or geology is a new challenge to the development of database systems. This thesis addresses three areas of the problem of integrating spatio-temporal objects into databases. First, a new representational model for continuously changing, spatial 3D objects is introduced and transferred into a small system of classes within an object-oriented database framework. The model extends simplicial cell complexes to the spatio-temporal setting. The problem of closure under certain operations is investigated. Second, internal data structures are introduced that represent instances of the (user-level) spatio-temporal classes. A new technique provides a compromise between compact storage and efficient retrieval of spatio-temporal objects. These structures correspond to temporal graphs and support updates as well as the maintainance of connected components over time. Third, it is shown how to realise further operations on the new type of objects. Among these operations are range queries, intersection tests, and the Euclidean distance function

3D Data and Model Management for the Geosciences with Particular Emphasis on Topology and Time

The doctoral thesis deals with the examination of methods for topological data handling, as well as designing and implementing a toolkit for the geosciences for management of topological and temporal 3D data and models in geo-database architectures. The conceptual work and realisation process takes into account the management of multi LoD since it is considered to be an integral part of geo-modelling

If you build it, will they come? Evolution towards the application of multi-dimensional GIS to fisheries-oceanography

The development of new technologies in science is a balance between existence and use. There are three versions of this duality – something is built and users come, something is built and users don’t come, and, finally, potential users show up but the ballpark has not yet been built. In each instance there is a combination of three factors at work. The first is a scientific need for a type of data or analysis. The second is a technology or technique developed to meet the need; and the third is a perception that using the technology is somehow "better" that the existing tools and that the tool is easy to use. This work examines closely the development of a tool within oceanography – the Stommel diagram for displaying the time and space spectra of oceanographic phenomena – and the spread of the use of the diagram to other disciplines. The diagram was the product of a number of elements - the mind of a truly original oceanographer, the development of equipment able to collect the detailed temporal and spatial data used to create the plot, and the rise of "big oceanography", which led Stommel to argue graphically for taking care in the design of expeditions. Understanding the spread of the Stommel plot provides a viewpoint for examining the unexpectedly slow development of multi-dimensional geographic information systems (GIS). The development of GIS’s began in the 1970's. Data structures to hold multi-dimensional data have been developed, tools for multidimensional map algebra have been created, and test applications have been developed. The current non-development of multi-dimensional GIS is examined as a background for creating and disseminating GeoModeler, a prototype of scientific GIS able to ingest and display multi-dimensional data. Taking advantage of recent technical developments, we have created a scientific GIS that can display three-dimensional oceanographic data. GeoModeler is used to visually explore and analyze the relationship between water temperature and larval walleye pollock (Theragra chalcogramma) growth in Shelikof Strait, Alaska