Analysis of the Olfactory Signal
The electronic nose is an instrument able to detect and recognize odors, that is the volatile substances in the atmosphere or emitted by the analyzed substance. This device can react to a gas substance by providing signals that can be analyzed to classify the input. It is composed of a sensor array (MOS sensors, in our case) and a pattern classification process based on machine learning techniques. Each sensor reacts in a different way to the analyzed substance, providing multidimensional data that can be considered as a unique olfactory blueprint of the analyzed substance. In our work, we used an array composed of six Metal Oxide Semiconductor (MOS) sensors.
Nowadays the research on olfactory systems has become very lively, most of all because of the multitude of applications in which it has been successfully used, as the environmental field, the medical one, security (detection of explosives or drug) and so on. The olfactory signal, as well as other signals perceived through human senses, transports much more information than human beings are able to perceive; an electronic nose is an instrument that allows to acquire this kind of signal. An electronic nose is composed by an array of electronic chemical sensors with partial speciﬁcity and an appropriate pattern recognition system able to recognize simple or complex odors.
At the moment research on the analysi of the olfactory signal at the AIRLab is focusing on medical applications: clinicians have indeed always considered odor as a fundamental information for the diagnosis, according to the fundamental principle of clinical chemistry, namely the fact that every pathology changes people chemical composition, modifying the concentration of some chemicals in the human body. For this reason an electronic nose could be used to automatically analyze substances produced and emitted from the human body ﬁnding, in a rapid and non invasive way, several diseases.
An electronic nose consists in three principal components: 1) Gas Acquisition System 2) Pre-processing and Dimensionality Reduction 3) Classiﬁcation Algorithm
The Olfactory Signal Analysis project is in the BioSignal_Analysis area.
- Lung Cancer Detection by an Electronic Nose (Master thesis, Claudio Trameri, Mauro Verdirosa)
There are various proposal for students interested in projects/thesis in the field of the olfactory signal analysis: