2004) described a simple transfer-function technique, which is mathematically equivalent to the solution of the CDE for a narrow pulse, and used this technique successfully to determine solute-transport parameters from measured breakthrough data in repacked soil columns.
The accuracy of fitting by the transfer-function method is evaluated by the root-mean-square error (RMSE) between the measured and estimated BTCs, given by:
This suggests that the solute-transport parameters might be determined from an early segment of the measured breakthrough data by the transfer-function method.
The mean travel time, [tau], and mass-dispersion number, N, of solute were fitted from each set of data by the transfer-function method (Eqn 2) using a non-linear least-square fitting technique.
These close fits suggest that the transfer-function method can be used to estimate solute-transport parameters from partial breakthrough data without the prolonged tail section.
Since the transfer-function method has been shown to provide accurate values of solute-transport parameters from complete BTCs (Mojid et al.
Figure 3 shows the transfer-function stated in Equation 1 with A = 1 and B = 1, as a function of" the phase shift [phi].
For further analysis, the oscillator loop must be broken up, and a transfer-function can be recorded.
This would not give the correct result for the transfer-function, since in the closed loop condition the output of the oscillator is terminated with its input's impedance and vice-versa.
o2] the voltage transfer-function can be defined and set to 1.
The parameters are also dependent on the used power, so this part of the modeling will produce the largest error in the transfer-function behavior.