Biological Pretreatment by Solid-State Fermentation of Oat Straw to Enhance Physical Quality of Pellets

Table 1

Coded levels for influencing factors used in the experiment.

Code	Factor
	(d)	(%)	(mm)	(°C)
1	35	70	150	34
0	28	65	100	28
−1	21	60	50	22
	7	5	50	6

is the level of each influencing factor.