Method knum.





parameters of constructor.


List of the default parameters.


Method knum.

Method concUnitsSorption.

Class SorptionModel controls the the amount of gas absorbed by the sensor, that emulates the non-linearity nature intrinsic for the polymeric sensors.

Function to get default constructor parameters of class SorptionModel.

Constructor method of SorptionModel Class.

Wrapper function SorptionModel.


The model is based on the extended Langmuir isotherm for a multi-component gas mixture, and has two parameters per analyte, Q denotes the sorption capacity and K stands for the sorption affinity.

Slots of the class:

sorptionModel List of model parameters 'K' and 'Q'.
Slots of the class:
knum Sensor number that encodes a UNIMAN sorption profile (1:17). The default value is 1.
gases Gas indices.
ngases The number of gases.
gnames Names of gases.
concUnits Concentration units external to the model, values given in an input concentration matrix.
concUnitsInt Concentration units internal for the model, values used numerically to evaluate the Langmuir relation.
sorptionModel A list that contains the Langmuir parameters.
srdata The reference data of Lanmuir parameters from UNIMAN dataset (see UNIMANsorption).
alpha (parameter of sensor non-linearity in mixtures) A scaling coefficient of non-linearity induced via the affinity parameter K. The default value is 2.25.

Methods of the class:

predict Predicts a model response to an input concentration matrix.

The plot method has three types (parameter y):

response (default) Shows a modeled trasnformation of concentration profile per analyte.
data Shows the reference data from UNIMAN dataset.
predict Depicts input and ouput of the model for all analytes.


We introduce a single parameter alpha of the model to control the level of non-linearity simulated by the Langmuir isotherm. This parameter alpha defines a normalization across the 17 UNIMAN sorption profiles from dataset UNIMANsorption, scaling K values based on other two parameters Kmin (default value 1 and Kmax (default value 150). Normalization can be disable by setting parameter Knorm to FALSE, that results in usage of the sorption K parameters, equal to UNIMAN ones.


# sorption model: default initialization sm <- SorptionModel() # get information about the model show(sm)
Sorption Model (knum 1), alpha 2.25
Sorption Model - knum 1 - 3 gases A, B, C

# model: custom parameters # almost linear model sm <- SorptionModel(alpha=0.01, gases=c(1, 3)) plot(sm, main="Almost linear model, non-linearity 0.01")

# non-linear model sm <- SorptionModel(alpha=0.3, gases=c(1, 3)) plot(sm, main="Non-linear model, non-linearity 0.5")

# saturated model sm <- SorptionModel(alpha=0.5, gases=c(1, 3)) plot(sm, main="Saturated model, non-linearity 1")

# model with UNIMAN sorption parameters sm <- SorptionModel(Knorm=FALSE, gases=c(1, 3)) plot(sm, main="Model with UNIMAN parameters (no normalization)")

# method plot # - plot types 'y': response, data, predict sm <- SorptionModel() # default model plot(sm, "response", main="plot(sm, 'response')")

# default plot type, i.e. 'plot(sm)' does the same plotting plot(sm, "data", main="plot(sm, 'data')")

plot(sm, "predict", main="plot(sm, 'predict')")

See also