Abstract: Aiming at the problems of long period of manual measurement data and data missing of on-line monitoring device for gas extraction, the relationship between gas extraction time and cumulative extraction volume of underground pipeline and the repair algorithm of gas monitoring data in two cases of single point missing and continuous missing are studied by data fitting method, and a set of gas monitoring data repair algorithm is designed and implemented. Evaluation system of gas drainage meets the standard. The test results of the extraction evaluation unit of N1633 North return air roadway in Shigou Coal Mine show that the system meets the evaluation requirements of the gas extraction standard, and provides an application demonstration for the gas extraction standard at the present stage of the mine.

Key words: data preprocessing, data fiting, data repair, expectation maximization, criteria for achieving standards