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Indexed by:期刊论文

Date of Publication:2013-07-01

Journal:SENSORS

Included Journals:SCIE、PubMed、Scopus

Volume:13

Issue:7

Page Number:9160-9173

ISSN No.:1424-8220

Key Words:sensor drift; metal oxide sensors; ensemble method; dynamic weights

Abstract:Sensor drift is currently the most challenging problem in gas sensing. We propose a novel ensemble method with dynamic weights based on fitting (DWF) to solve the gas discrimination problem, regardless of the gas concentration, with high accuracy over extended periods of time. The DWF method uses a dynamic weighted combination of support vector machine (SVM) classifiers trained by the datasets that are collected at different time periods. In the testing of future datasets, the classifier weights are predicted by fitting functions, which are obtained by the proper fitting of the optimal weights during training. We compare the performance of the DWF method with that of competing methods in an experiment based on a public dataset that was compiled over a period of three years. The experimental results demonstrate that the DWF method outperforms the other methods considered. Furthermore, the DWF method can be further optimized by applying a fitting function that more closely matches the variation of the optimal weight over time.