Reparallelization and Migration of OpenMP Programs

Typical computational grid users target only a single cluster and have to estimate the runtime of their jobs. Job schedulers prefer short-running jobs to maintain a high system utilization. If the user underestimates the runtime, premature termination causes computation loss; overesti-mation is penalized by long queue times. As a solution, we present an automatic reparallelization and migration of OpenMP applications. A reparallelization is dynamically computed for an OpenMP work distribution when the num-ber of CPUs changes. The application can be migrated between clusters when an allocated time slice is exceeded. Migration is based on a coordinated, heterogeneous check-pointing algorithm. Both reparallelization and migration enable the user to freely use computing time at more than a single point of the grid. Our demo applications successfully adapt to the changed CPU setting and smoothly migrate between, for example, clusters in Erlangen, Germany, and Amsterdam, the Netherlands, that use different processors. Benchmarks show that reparallelization and migration im-pose average overheads of about 4 % and 2%. 1

An Ontology-based Adaptation Framework for Multimodal Interactive Systems

Abstract. One approach for improving the usability of interactive systems is adapting them to user behavior, which can be accomplished by adaptation rules. The advantage of rules is that they are explicit and intuitive, but their expressivity depends on the richness of the underlying data model. In this paper, a framework for the adaptation of interactive systems is presented that relies on a uniform ontology-based information representation, for instance for the system and the user model. Such a description can then be employed by the adaptation rules. By adding semantic information, the scope of the rules is widened. Moreover, special emphasis is put on the dynamic aspects of interactive systems, mainly the interaction of the user with the system and system events. Exemplary rules used in an interactive TV prototype illustrate this framework

ATP-dependent hydroxylation of an unactivated primary carbon with water

Monooxygenases catalyse the hydroxylation of C-H bonds using oxygen as a co-substrate, which, in turn, is unavailable for anaerobic bacteria. Here, the authors report a three-step reaction cascade involving two hydroxylases and one dehydratase which hydroxylate the C26 methyl group of cholesterol with water as a co-substrate