Predicting the Viscosity of Petroleum Emulsions Using Gene Expression Programming (GEP) and Response Surface Methodology (RSM)

Table 2

Experimental design parameters.

Parameters	(−1)	0	1
X1, aging time (days)	1.0	4.0	7.0
X2, water viscosity (cP)	0.890	0.945	1.000
X3, oil viscosity (cP)	18	26.5	35
X4, water cut (v/v%)	20	35	50
X5, amount of solids (wt%)	0.17	0.29	0.41