Analysis modules tend to be set up as one way flow of information, i.e a clear distinction between cause and effect or input and output. However, as the speed of analysis approaches real time (or faster than movie rate), it becomes increasingly difficult for an external user to distinguish between cause and effect because they are simultaneously available for visualization and can be viewed in any desired order. This paper discusses some potential benefits of setting up a Flipping Analytical Coin Tool (FACT) which closes the information flow loop, thereby taking advantage of the apparent equivalence between forward and reverse analysis. A simple and stable non-linear algorithm is derived which uses the principle of dimensional similarity in each independent dimension of the problem to efficiently calculate the reverse path of high speed multidimensional functions or analysis modules. An example application in the field of conceptual thermodynamic design of a turbofan engine demonstrates the usefulness of this approach to interactive design optimization of complex engineering systems. The method given here is applicable to both well and ill-posed problems.

Design Aids (acm B.5.2), PERFORMANCE OF SYSTEMS (acm C.4), Organization and Design (acm D.4.7), Modes of Computation (acm F.1.2), COMPUTER-AIDED ENGINEERING (acm J.6)
Optimization and variational techniques (msc 65K10), Multi-objective and goal programming (msc 90C29), Sensitivity, stability, parametric optimization (msc 90C31), Design techniques (robust design, computer-aided design, etc.) (msc 93B51)
Software Engineering [SEN]

Shahroudi, K.E. (1997). Flipping the analytical coin : closing the information flow loop in high speed (real time) analysis. Software Engineering [SEN]. CWI.