Currently, researches on closed-set gas classification tasks has achieved great success in the electronic nose (E-nose) field. E-nose, however, faces a more challenging and realistic task in open-set gas classification. To find an accurate open-set gas classification model, we proposed a MSE-TCN, which integrates squeeze-and-excitation residual network (SE-ResNet) internally into the temporal convolutional network (TCN) and expands the channels number of TCN, forming a multi-scale feature extraction encoder, and realizes open-set gas classification using the OpenMax algorithm. The underlying SE-ResNet module focuses on the relatively important sensor channels, while Multi-scale TCN thoroughly captures temporal relationships between the E-nose data from three scales, and the OpenMax identifies the unknown classes by redistributing the probability. The gas sensing performance of the sensors used in the self-sampling dataset was analyzed, demonstrating the reliability of the data acquisition. Subsequently, comparative experiments based on self-sampling dataset and public dataset were performed to determine the number of encoders and demonstrate the necessity of the SE-ResNet module. Meanwhile, ablation experiments demonstrate the effectiveness of our proposed model. In addition, the comparative experiments of the open-set classifiers show MSE-TCN achieves the highest accuracies of 0.9245 and 0.9387 among all the models on both datasets for open-set classification, respectively. As a result, this model provides an effective method for high accuracy gas classification for both closed-set and open-set in E-nose field.
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