Research Challenges in Modeling and Simulation for Engineering Complex Systems

ion layer Function Model layer The code of a particular model (or component) Model framework layer Collection of model classes, components, and libraries for a single application area, such as network simulation or PDE solution Simulator layer Provides a single paradigm for simulation time, space, naming, parallelism, and synchronization for use in one component of a (possibly) federated simulation Component federation layer Provides interface code to allow independently created submodels, possibly written in different languages, to communicate, synchronize, and interoperate in various ways to become a single federated model Load management layer Within one parallel model execution, measures resource utilization (time, energy, bandwidth, memory) at runtime and dynamically manages or migrates loads to optimize some performance metric Ensemble layer Runs many instances of the same model as an ensemble in a single large job, for such purposes as parameter sensitivity studies, parameter optimization, variance estimation. Handles scheduling, failures, accounting, and time estimates, allocates file directories, decides on ensemble termination, etc. Operating system /job scheduler layer Runs independent jobs in parallel. Provides processes, interprocess communication, I/O, files systems, etc. 62 C. Carothers et al.