ABSTRACT
The Functional Resonance Analysis Method makes an important distinction between a model of the target system and the instantiations of the model. It represents the set of functions that together account for the activity being analysed and the potential couplings among functions. An instantiation represents a concrete instance of the model for given circumstances and set of conditions, and the details provided by the instantiation makes it possible to be more precise about whether and how the potential variability can become actual variability. Resources or Execution Conditions represent something that is needed and consumed by a function, or something that must be present while a function is carried out. Time represents the various temporal relations that can have an influence on how a function is carried out. The upstream-downstream couplings can describe how the variability of functions may spread in a way that is fundamentally different from the usual linear propagation.
