A Chemical Work ow Engine for Scienti c Work ows with Dynamicity Support

In this paper the notion of a Chemical Work ow Engine (CWE) is introduced to support the enactment of scienti c work ows, i.e. computationally intensive tasks involving large datasets. The execution of scienti c work ows require the coordinated use of a large quantity of resources and scheduling of the activities. Furthermore, these workows may pose various dynamic features that need a special elaboration, either due to the inherent structure of the work ow, changes in the environment or interaction. The concept of CWE introduced in this paper is focused on these issues with the aim of creating a highly abstract selfevolving coordination model for work ow execution. The model is based on the foundations of classical work ow formalisms, particularly, Event-driven Process Chains, and realized through a completely new paradigm: the chemical computational model. The coordination is based on a nature metaphor and follows the principles of the chemical reactions. The proposed coordination model is inherently concurrent, exploits all potential parallelism, able to dynamically react to any changes in the environment or workow structure.