Scheduling precedence constrained jobs on identical parallel machines is a well investigated problem with many applications. AND/OR-networks constitute a useful generalization of standard precedence constraints where certain jobs can be executed as soon as at least one of their direct predecessors is completed. For the problem of scheduling AND/OR-networks on parallel machines, we present a 2-a...

Precedence graph grammars are of major interest in all those applications of graph grammars, where highly efficient parsers are needed. Up to now there are no other graph parsers with the same performance. Due to the fact, that even regular graph grammars with very restricted embedding relations have a NP-complete membership problem, different kinds than Chomsky-like restrictions have to be imp...

We consider a set of n tasks, each of them is composed by a set of sequential operations. A set of bu ers B is given : each bu er b 2 B is de ned between two tasks Ti ! Tj , has a weight wb and is managed as a FIFO structure. Some operations from Ti write data in the bu er b, other from Tj get data in b. The writings and readings on bu ers generate precedence constraints between the operations....

A stochastic probing problem consists of a set of elements whose values are independent random variables. The algorithm knows the distributions of these variables, but not the actual outcomes. The only way to learn the actual outcomes is to probe these elements. However, there are constraints on which set of elements may be probed. (E.g., we may have to travel in some metric to probe elements b...