Table 3.

ANOVA results of different models

Variables/Factors	F-value
	df	ΔE	RR	Hardness	Specific Energy
Model	9	13.73***	13.89***	5.38***	130.24***
V-Air Velocity	1	0.03	23.76***	1.11	149.22***
T-Air Temperature	1	30.70***	19.91***	5.96**	15.46***
M-Microwave Power	1	5.82**	78.30***	16.80***	997.05***
VT	1	4.65*	0.82	5.03**	1.56
VM	1	1.80	1.15	6.66**	4.25*
TM	1	0.80	0.55	4.05*	1.71
V2	1	49.42***	0.02	1.59	0.28
T2	1	36.78***	0.24	3.56*	2.45
M2	1	5.32***	0.20	2.85	0.03
Residual	10
Lack of Fit	5	12.15***	1.84	1673.03***	2.05
Pure Error	5
Total	19

***Significant at p < 0.01, **p < 0.05, *p < 0.1