位于宾夕法尼亚州布鲁斯顿的美国矿务局匹兹堡研究中心已经开发出若干种仪器,称之为煤层界面探测仪。用于分析震动传感器输出信息的此种探测仪安装在截煤机上。根据震动反应,截煤机手便能及时判断是否截割到了岩面。匹兹堡研究中心开发的另一项新技术,是用环氧粘合剂将过荷指示器或地震检波器安在煤层或矿井顶板。机器截煤时,产生的强地震信号会在煤层中远距离传播,到达煤层表面。分析这类震动,特别是利用具有自 The Pittsburgh Research Center at the US Bureau of Mines, in Brewton, PA, has developed several instruments called coalbed surface detectors. This detector, which is used to analyze the output of a vibration sensor, is mounted on a coal cutter. According to the vibration response, the coal cutter can judge whether it is cut to the rock surface in time. Another new technology developed by the Pittsburgh Research Center is the use of an epoxy adhesive to load indicators or geophones on coal or mine roofs. When the machine intercepts coal, the strong earthquake signal will propagate long-distance in coal seam and reach the surface of coal seam. Analysis of such vibrations, especially the use of self