Discrimination of Different AE and EMR Signals during Excavation of Coal Roadway Based on Wavelet Transform

Minerals

Enyuan Wang¹  Baolin Li¹  Zhonghui Li¹  Youcang Ji²  Jing Huang²  Yue Niu³  Nan Li⁴ 

[1] Key Laboratory of Gas and Fire Control for Coal Mines, China University of Mining and Technology, Ministry of Education, Xuzhou 221116, China;Safety Technology Center, Sichuan Coal Mine Safety Administration, Chengdu 610046, China;State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Xuzhou 221116, China;State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Xuzhou 221116, China;

关键词: acoustic emission;    electromagnetic radiation;    interference signals;    danger signals;    wavelet transform;    signal discrimination;   

DOI  :  10.3390/min12010063

来源: DOAJ

【 摘 要 】

During the process of coal road excavation, various interference signals, induced by environmental noise, drilling, and scraper loader, will affect the risk assessment of coal and gas outburst using acoustic emission (AE) and electromagnetic radiation (EMR) monitoring technology. To distinguish between different interference signals and danger signals, discrete wavelet transform (DWT) was used to decompose and reconstruct signals, and continuous wavelet transform (CWT) was used to obtain the time-frequency plane. The research results show that: (1) interference signals generally exhibit fluctuating changes within small ranges; in comparison, the intensity of AE and EMR signals caused by coal and rock fracture is found to continuously rise for a long period (longer than 2 h). (2) Different interference signals and danger signals differ significantly in their time-frequency plane. (3) Through decomposition and reconstruction of original signal, obvious precursor information can be found in the time-frequency plane of reconstructed signals.

【 授权许可】

Unknown