Your response is Yield. Your factors are the following:
Time: The range of interest is 500 to 560 seconds.
Temperature: The range of interest is 350 to 750 degrees Kelvin.
Catalyst: Three catalysts A, B, and C, must be tested.
1.
Select DOE > Custom Design.
2.
Because your goal is to maximize Yield, leave the Goal set to Maximize.
4.
Click Add Factor > Continuous.
5.
Click Add Factor > Categorical > 3 Level.
6.
Rename the factors Time, Temperature, and Catalyst.
7.
Change the Values for Time to 500 and 560.
8.
Change the Values for Temperature to 350 and 750.
9.
Change the Values for Catalyst to A, B, and C.
Figure 4.46 Factor Settings
10.
Click Continue.
1.
Select Use Disallowed Combinations Filter in the Define Factor Constraints outline.
2.
Select Temperature and Catalyst from the Add Filter Factors list.
3.
Click Add.
This disallows factor settings with Temperature values below 400.
Together with the constraint on Temperature, this disallows factor settings for which Catalyst is B and Temperature is below 400.
6.
7.
Select Temperature and Catalyst from the Add Filter Factors list. (Your earlier selection may have been retained.)
8.
Click Add.
This disallows factor settings with Temperature values above 650.
Together with the constraint on Temperature, this disallows factor settings for which Catalyst is C and Temperature is above 650.
Figure 4.47 Constraints Defined
2.
Click OK to dismiss the alert.
Note: Setting the Random Seed in step 3 and Number of Starts in step 4 reproduces the exact results shown in this example. In constructing a design on your own, these steps are not necessary.
3.
(Optional) From the Custom Design red triangle menu, select Set Random Seed, type 654321, and click OK.
4.
(Optional) From the Custom Design red triangle menu, select Number of Starts and set it to 1000. Click OK.
5.
Click Make Design.
Figure 4.48 Design Satisfying Constraints
Recall that the design region consists of settings of Time between 500 and 560 and Temperature between 350 and 750. To obtain a geometric view of the design points within the design region, do the following:
1.
Click Make Table.
2.
Select Graph > Graph Builder.
3.
Select Time and Temperature and drag them to the center of the template.
4.
Deselect the Smoother icon. This is the second icon from the left above the template.
5.
Select Catalyst and drag it to the Group X zone at the top of the template.
Figure 4.49 Design Points for Three Levels of Catalyst
6.
Double-click the Temperature axis.
Next to Value, enter 350.
Click Add.
Next to Value, enter 750.
Click Add.
8.
Figure 4.50 Design Bounds on Temperature for Three Levels of Catalyst
9.
Next to Value, enter 500.
Click Add.
Next to Value, enter 560.
Click Add.
11.
12.
Click Done.
Note: The plot in Figure 4.51 is vertically resized.
Figure 4.51 Design Regions for Three Levels of Catalyst
Six of the settings for Catalyst A fall on the edges of the design region. All Temperature setting for Catalyst B are above the 400 degree constraint and all Temperature settings for Catalyst C are below the 650 degree constraint.

Help created on 7/12/2018