Topics for PhD Theses and Master Theses

So far, spatial databases have mainly dealt with the management of two-dimensional geometric data. This has turned out to be sufficient for many spatial applications. But on the other hand, our world is three-dimensional. In this project, first, possible applications are investigated that require or would greatly benefit from a treatment of three-dimensional data and operations. This study should lead to an identification of the essential three-dimensional spatial data types and operations. In the following, the data types and operations are formally defined and implemented according to a number of design criteria posed before. Examples of such design criteria are generality of the data type definition, closure properties of data types, and numerical robustness. For testing and demonstrating purposes, a graphical user interface for the visualization of 3D spatial objects and the evaluation of operations should be included. Another important aspect is to design mechanisms to integrate these types into an extensible database system. Appropriate for: PhD Status: assigned Desired or required knowledge: databases in general, spatial databases, 3D computational geometry; programming skills in C++ Introducing Literature: Ralf Hartmut Güting. An Introduction to Spatial Database Systems. VLDB Journal (Special Issue on Spatial Database Systems), 7(3), 231-246, 1994. Markus Schneider. Spatial Data Types for Database Systems − Finite Resolution Geometry for Geographic Information Systems. LNCS 1288, Springer-Verlag, 1997. Aristides A. G. Requicha. Geometric Modelling: A First Course. 1995-2000. URL: http://wwwpal.usc.edu/~requicha/book.html Sara Anne McMains. Geometric Algorithms and Data Representation for Solid Freeform Fabrication. Dissertation, 2000. URL: http://www.me.berkeley.edu/~mcmains/thesis.pdf Topic 3: Implementation of Past-Oriented Spatio-Temporal Data Types and their Integration into Database Systems Abstract. Spatio-temporal database systems deal with geometries changing over time. If only the position in space of an object is relevant, then moving point is a basic abstraction. Examples are people walking around, animals migrating over time, cars driving in a city, or planes connecting cities or countries. If also the extent is of interest, then the moving region abstraction captures moving as well as growing or shrinking regions. Examples are storms traversing a country and at the same time altering their shape, forest shrinking, and high/low pressure areas or temperature zones changing dynamically. This leads to spatio-temporal data types, and spatio-temporal databases are essentially moving objects databases. A conceptual design for spatio-temporal data types has already been proposed. The remaining, important, and challenging task is to find an efficient and numerically robust implementation for it. For testing and demonstrating purposes, a Spatio-temporal database systems deal with geometries changing over time. If only the position in space of an object is relevant, then moving point is a basic abstraction. Examples are people walking around, animals migrating over time, cars driving in a city, or planes connecting cities or countries. If also the extent is of interest, then the moving region abstraction captures moving as well as growing or shrinking regions. Examples are storms traversing a country and at the same time altering their shape, forest shrinking, and high/low pressure areas or temperature zones changing dynamically. This leads to spatio-temporal data types, and spatio-temporal databases are essentially moving objects databases. A conceptual design for spatio-temporal data types has already been proposed. The remaining, important, and challenging task is to find an efficient and numerically robust implementation for it. For testing and demonstrating purposes, a