Create an eight-trial unreplicated two-level fractional factorial experiment. List the trials in the sequence planned for investigation.
(a) Include the effects of four factors:
A—150 to 300;
B—0.2 to 0.8;
C—22 to 26;
D—1200 to 1800.
(b) Add five center points.
(c) Your manager insists that the best combination is when A 150, B 0.8, C 26, and D 1800. If the above design does not contain this combination, make adjustments so that this combination will occur in the experiment.
(a) Determine if there are any outlier data points. Comment on the techniques used to make the assessment.
(b) Determine what factors (if any) are statistically significant and to what significance level.
(c) Determine if there are any two-factor interactions. Determine and illustrate the combinations from any interactions that give the greatest results.
(d) Write a model equation with the statistically significant terms.
(e) If B high (i.e., ) was 30 volts and B low (i.e., ) was 40 volts, determine from the model equation the expected output at 32 volts if all other factors are set to nominal conditions.