Configuring the Optimization Constraints

You can select the parameters that will be used as constraints during execution. The list of parameters includes all output parameters from the Six Sigma component and output parameters from the subflow components, if they are not mapped to any parameters in the Six Sigma component. When any subflow parameter is selected as a constraint, a corresponding parameter is created in the Six Sigma component and in the Optimization component.

  1. Double-click the Six Sigma component icon .

    The Six Sigma Component Editor appears.

  2. From the Six Sigma Component Editor, click the Optimization tab.

  3. Click the Constraints subtab.

  4. Right-click in the table to access various options for working with constraints.

    For more information, see Setting Table Options.

  5. Perform the following options, which may vary based on your model design:

    1. Determine which parameters you want to use as constraints by selecting the corresponding check boxes in the first column. Alternatively, you can click Check to add all the selected parameters as constraints (including array elements). To clear all the parameters, click Uncheck.

      If no parameters are selected, you will be prompted to add all parameters as constraints.

    2. Set the Lower Bound and Upper Bound in the corresponding columns.
    3. Set the constraint’s Target in the corresponding column.
    4. Set the constraint’s Scale Factor and Weight Factor in the corresponding columns. Scale factors are used to bring constraint values to the same order of magnitude to improve the efficiency of the optimizers. Weight factors are used to change the importance of various constraints.

      The value of each constraint is calculated as follows:

      • Constraint  Value⁢(Lower⁢Bound) =(LB−Parm×W/S)
      • Constraint⁢ Value⁢(Upper⁢Bound) =(Parm−UB)×W/S
      • Constraint⁡ Value⁢(Target) =(Parm−1)×W/S

      where LB is the lower bound value, UB is the upper bound value, T is the target value, Parm is the parameter value, W is the weight factor, and S is the scale factor.

  6. If desired, click Edit at the bottom of the editor to set constraint options.

    For more information, see Editing Attributes for Multiple Parameters.

  7. If desired, map any of these constraint attributes to parameters.

    For more information, see Mapping Options and Attributes to Parameters.

  8. Click OK to save your changes and to close the Six Sigma Component Editor.

    When you select Six Sigma Optimization and click OK or Apply for the first time, the model is modified by embedding the Six Sigma component under an Optimization component. All optimization criteria are copied to the Optimization component and all selected parameters will be mapped up to the Optimization component. You can still edit the optimization criteria in the Six Sigma Component Editor.