Query optimization is used frequently in relational database management systems. Most existing techniques are based on reordering the relational operators, where the most selective...
The paper presents a simple and concise proof of correctness of the magic transformation. We believe it may provide a useful example of formal reasoning about logic programs. The ...
This article describes a particular use of ontologies for visualising maps in a browser window. Geographic data are represented as instances of concepts in an ontology of transpor...
As parallel machines become part of the mainstream computing environment, compilers will need to apply synchronization optimizations to deliver e cient parallel software. This pap...
In this paper we present how refactoring of object-oriented programs can be accomplished by using refinement. Our approach is based on algebraic laws of an object-oriented languag...