Table 1 Scaling factor α for each type of WS-HEQ

0.6

${\text{WS-HEQ}}_{\text{II}}^{\left(1\right)}$

0.6

0.6

${\text{WS-HEQ}}_{\text{II}}^{\left(2\right)}$

0.6

0.5

${\text{WS-HEQ}}_{\text{II}}^{\left(3\right)}$

0.7

0.7

${\text{WS-HEQ}}_{\text{II}}^{\left(4\right)}$

0.6