The capability of a natural gas transmission pipeline inspection tool to detect cracks and
corrosion is affected by a number of factors, namely, magnetization level, sensor spacing,
radial liftoff, and circumferential alignment of the sensors relative to a defect.
The first two factors are design parameters and are controllable factors. The last two factors
are hard to control on site and are treated as noise factors. The Taguchi method is
utilized to obtain an efficient set of design parameters that are robust with respect to
noise and other variations in test parameters. This article first introduces the basic idea
underlying the Taguchi method. Procedures for designing and simulation of experiments
are given along with simulation results, which are analyzed using the main effects and
analysis of variance techniques. Conclusive remarks based on the analysis are finally
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