Geometric correction factor $G_{corr}$ for jacket around each core

The equation for three-core cables with jacket around each core is based on the Jicable paper 'Thermal analysis of three-core SL-type cables with jacket around each core using the IEC standard' by L.D. Ramirez et al., dated 2019.

Symbol
$G_{corr}$
Formulae
$\frac{\left(X_{G2}+0.006\right) \left(\frac{t_{shj}}{t_{sha}}+0.061\right) \left(a_{shj} {\rho_{shj}}^2+b_{shj} \rho_{shj}+c_{shj}\right)}{1000}$