EFFICIENCY OF LINEAR AND NON-LINEAR CLASSIFIERS FOR GAS IDENTIFICATION FROM ELECTROCATALYTIC GAS SENSOR

Electrocatalytic gas sensors belong to the family of electrochemical solid state sensors. Their responses are acquired in the form of I-V plots as a result of application of cyclic voltammetry technique. In order to obtain information about the type of measured gas the multivariate data analysis and pattern classification techniques can be employed. However, there is a lack of information in literature about application of such techniques in case of standalone chemical sensors which are able to recognize more than one volatile compound. In this article we present the results of application of these techniques to the determination from a single electrocatalytic gas sensor of single concentrations of nitrogen dioxide, ammonia, sulfur dioxide and hydrogen sulfide. Two types of classifiers were evaluated. i.e. linear Partial Least Squares Discriminant Analysis (PLS-DA) and nonlinear Support Vector Machine (SVM), The efficiency of using PLS-DA and SVM methods arc shown on both the raw voltammetric sensor responses and pre-processed responses using normalization and auto-scaling.