Controlled Query Evaluation in General Semantics with Incomplete Information

Inauguraldissertation an der Philosophisch-naturwissenschaftlichen Fakultt der Universitt Bern.
The thesis describes possible mechanisms that allow manipulations of query-sequences in order to hide secret information from a potentially malicious query-agent.
This is investigated in a strictly formal way: The surrounding information framework is reduced to general semantics and allows modelling of incomplete information.