Institut F Ur Informatik Lehr-und Forschungseinheit F Ur Programmier-und Modellierungssprachen Oettingenstraae 67, D{80538 M Unchen Connuent Simpliication Rules Connuent Simpliication Rules

Institut F Ur Informatik Lehr-und Forschungseinheit F Ur Programmier-und Modellierungssprachen Oettingenstraae 67, D{80538 M Unchen Problem Solving with Model-generation Approaches Based on Puhr Tableaux in Proc. Problem-solving Methodologies with Automated Deduction, Workshop at Cade '98

Institut F Ur Informatik Lehr-und Forschungseinheit F Ur Programmier-und Modellierungssprachen Oettingenstraae 67, D{80538 M Unchen a Connuence Test for Concurrent Constraint Programs a Connuence Test for Concurrent Constraint Programs

We address the problem of identifying connuent parts of concurrent constraint programs. The connuence property guarantees that a concurrent program will always compute the same result independent of the execution strategy. In this paper, we introduce a simple test for connuence based on work in rewrite systems. Furthermore, we show how to use this test to certify the combination of concurrent c...

Institut F Ur Informatik Lehr-und Forschungseinheit F Ur Programmier-und Modellierungssprachen Oettingenstraae 67, D{80538 M Unchen Model Generation in Disjunctive Normal Databases Model Generation in Disjunctive Normal Databases

Algorithms for computing several classes of models for disjunctive normal databases are presented. We show how to eeciently compute minimal, restricted minimal, perfect, and stable models. The common feature of the advanced algorithms is that they are based on augmenting a model generating procedure with a set of hypotheses to guide its search for acceptable models and/or to interpret negation ...

Institut F Ur Informatik Lehr-und Forschungseinheit F Ur Programmier-und Modellierungssprachen Oettingenstraae 67, D{80538 M Unchen University Timetabling Using Constraint Handling Rules University Timetabling Using Constraint Handling Rules

Timetabling the courses offered at the Computer Science Department of the University of Munich requires the processing of hard and soft constraints. Hard constraints are conditions that must be satisfied, soft constraints however may be violated, but should be satisfied as much as possible. This paper shows how to model our timetabling problem as a partial constraint satisfaction problem and gi...

Institut F Ur Informatik Lehr-und Forschungseinheit F Ur Programmier-und Modellierungssprachen Oettingenstraae 67, D{80538 M Unchen Implementing Constraint Solvers: Theory and Practice Implementing Constraint Solvers: Theory and Practice

Our research is based on Constraint Handling Rules (CHR), a powerful language for writing constraint solvers. We investigate connuence of CHR programs. This property guarantees that a CHR program will always compute the same result for a given set of constraints independent of which rules are applied. We give a decidable, suucient and necessary syntactic condition for connuence. Finally we pres...