公开(公告)号：US20200033496A1

公开(公告)日：2020-01-30

申请号：US16343407

申请日：2018-03-30

Applicant: University of Science and Technology Beijing ,  Zhong-an Academy of safety Engineering

Inventor： Zhenlei LI ,  Xueqiu HE ,  Dazhao SONG ,  Shengquan HE ,  Donghui LI

IPC: G01V3/12 ,  E21F17/18 ,  G01L5/00 ,  G01N27/72

Abstract: A monitoring and forewarning method for coal-rock dynamic disasters based on an electromagnetic radiation and an earth-sound monitoring includes the following steps: (1) calculating the weighted average value of research parameter P(t) during a time period according to the monitoring data collected by the electromagnetic radiation and the earth-sound monitoring system in real time; (2) calculating D(t), the deviation value of P(t); (3) calculating |D(t)| as the deviation threshold value, the average value of |D(t)| during period of normal mining of the working surface; (4) calculating DS, the number of times that D(t) is greater than |D(t)| in one day; (5) normalizing DS to obtain the monitoring and forewarning index ε; (6) forewarning the hazard state of dynamic disaster of the working surface in real time according to ε and forewarning method, determining hazard level.

公开(公告)号：US20230417943A1

公开(公告)日：2023-12-28

申请号：US17940005

申请日：2022-09-08

Applicant: University of Science and Technology Beijing

Inventor： Dazhao SONG ,  Yuqing CHENG ,  Xueqiu HE ,  Menghan WEI ,  Yongjun TONG

IPC: G01V3/08

CPC classification number: G01V3/081

Abstract: A method of locating a failure of coal-rock-concrete based on vector features of a near-field electromagnetic field is provided. The method senses and records the real electromagnetic field vector information in space by arranging a triaxial electromagnetic sensor array around a coal-rock-concrete body, and realizes the localization of the failure areas of the coal-rock-concrete body by establishing an electromagnetic radiation localization model for the failures of the coal-rock concrete body. The electromagnetic radiation localization model for the failures of the coal-rock concrete body approximates the radiation source of electromagnetic radiation generated by failures as a dipole with a dipole moment, so as to realize the localization of a large number of relatively small-intensity failures during the disaster incubation stage and evolution process, realize the monitoring and early warning of the final disaster locations, and further improve the reliability of electromagnetic radiation positioning technology.

公开(公告)号：US20190277942A1

公开(公告)日：2019-09-12

申请号：US16348508

申请日：2018-03-30

Applicant: University of Science and Technology Beijing ,  Zhong-an Academy of safety Engineering

Inventor： Dazhao SONG ,  Xueqiu HE ,  Zhenlei LI ,  Menghan WEI ,  Quan LOU ,  Anhu WANG

IPC: G01S5/04 ,  G01V3/12

Abstract: A method of locating a coal-rock main fracture by an electromagnetic radiation from a precursor of a coal-rock dynamic disaster is provided. At least four groups of three-component electromagnetic sensors are arranged in the underground tunnels, and each group of sensors includes three directive antennas for receiving electromagnetic signals orthogonal to each other. The electromagnetic signals are collected by a monitoring host. The signals are ensured to be received by different sensors synchronously via an atomic clock. The direction of the magnetic field line is determined by performing a vector superposition on strengths of the three-component electromagnetic signals of each group of sensors. The planes of electromagnetic wave propagation perpendicular to the direction of the magnetic field line are determined accordingly. The location of the coal-rock fracture is determined by the intersection point of the planes of electromagnetic wave propagation determined by the multiple groups of sensors.