Prediction of Final Displacement of Tunnels in Time-Dependent Rock Mass Based on the Nonequidistant Grey Verhulst Model

Table 2

The estimated values of parameters for NGMs by the least-square method.

Grey model	Model parameter	Section I		Section II
		zA	cBC	zA	cBC
NGM(1, 1)	A	0.0085	0.0051	0.0067	0.0058
	B	1.2743	3.2129	1.3674	4.0326
NGVM and INGVM	A	−0.1505	−0.1701	−0.1096	−0.1132
	B	−2.8344e-3	−1.1378e-03	−1.0417e-3	−3.0344e-4