Computer-Based Methods for Constructing Two-Level Fractional-Factorial Experimental Designs with a Requirement Set

Steven L. Forsythe


This dissertation developed four methodologies for computer-aided experimental design of two-level fractional factorial designs with requirement sets (DOE/RS). The requirement sets identify all the experimental factors and the appropriate interaction terms to be evaluated in the experiment. Taguchi graphs and similar manual methods provide techniques for solving the DOE/RS problem. Unfortunately, these methods are limited because they become difficult to use as the number of factors or interaction terms exceeds ten. This research showed that the DOE/RS problem belongs to a class of difficult-to-solve problems known as NP-Complete. It is the combinatorial nature of NP-Complete problems that causes them to become computationally challenging as the size of the problem increases. Heuristics are often used to find good solutions to large NP-Complete problems.