1. Selectivity Enhancement in Multisensor Systems Using Flow Modulation Techniques
- Author
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J.L. Ramírez, Benachir Bouchikhi, Cristhian Durán, Eduard Llobet, Nicolau Cañellas, Jesus Brezmes, and Noureddine El Barbri
- Subjects
Discrete wavelet transform ,Computer science ,Oxide ,Metal oxide gas sensor ,computer.software_genre ,lcsh:Chemical technology ,Biochemistry ,Article ,Analytical Chemistry ,Metal ,chemistry.chemical_compound ,support vector machine ,lcsh:TP1-1185 ,Electrical and Electronic Engineering ,Instrumentation ,wavelet transform ,flow modulation ,Wavelet transform ,Atomic and Molecular Physics, and Optics ,Support vector machine ,Identification (information) ,Flow (mathematics) ,chemistry ,visual_art ,visual_art.visual_art_medium ,Data mining ,Transient (oscillation) ,Selectivity ,Biological system ,computer - Abstract
In this paper, the use of a new technique to obtain transient sensor information is introduced and its usefulness to improve the selectivity of metal oxide gas sensors is discussed. The method is based on modulating the flow of the carrier gas that brings the species to be measured into the sensor chamber. In such a way, the analytes’ concentration at the surface of the sensors is altered. As a result, reproducible patterns in the sensor response develop, which carry important information for helping the sensor system, not only to discriminate among the volatiles considered but also to semi-quantify them. This has been proved by extracting features from sensor dynamics using the discrete wavelet transform (DWT) and by building and validating support vector machine (SVM) classification models. The good results obtained (100% correct identification among 5 volatile compounds and nearly a 89% correct simultaneous identification and quantification of these volatiles), which clearly outperform those obtained when the steady-state response is used, prove the concept behind flow modulation.
- Published
- 2008