  Mechanisms are a fundamental concept in many areas of science. Nonetheless,
there has been little effort to develop structures to represent mechanisms. We
explore the issues in developing a basic semantic modeling framework for
describing some types of mechanisms. We draw together threads from a number of
different approaches and then consider two examples. From this survey, we
propose a rich Semantic Modeling Framework (SMF) based on Transitionals and
hierarchies of Aggregates and Mechanisms, which could be implemented with the
XFO programming environment. Potentially, the framework will be useful for
developing direct-representation scientific research reports and community
models.
