| dGeeraerd_model {bioinactivation} | R Documentation |
First Derivate of Geeraerd's Model
Description
Calculates the first derivative of the Geeraerd's model at a given time for the model parameters provided and the environmental conditions given.
Usage
dGeeraerd_model(t, x, parms, temp_profile)
Arguments
t |
numeric vector indicating the time of the experiment. |
x |
list with the values of the variables at time |
parms |
parameters for the secondary model. No explicit check of their validity is performed (see section Model Parameters). |
temp_profile |
a function that provides the temperature at a given time. |
Details
This function is compatible with the function
predict_inactivation.
Value
A list with the value of the first derivatives of N and C_c at time
t.
Model Equation
\frac{dN}{dt} = -N \cdot k_{max} \cdot \alpha \cdot \gamma
\frac{dC_c}{dt} = - C_c \cdot k_{max}
\alpha = \frac {1}{1+C_c}
\gamma = 1 - \frac{N_{res}}{N}
k_{max} = \frac{1}{D_T}
log_{10}D_T = log_{10}D_R + \frac{T_R-T}{z}
Model Parameters
temp_ref: Reference temperature for the calculation,
D_R: D-value at the reference temperature,
z: z value,
N_min: Minimum value of N (defines the tail).
Notes
To define the Geeraerd model without tail, assign N_min = 0.
For the model without shoulder, assign C_0 = 0