double unitＩ 基本例句 双工炸区 This article recommends a mining technology for thin coal seam with mixed mining, exceeding length and double unit face mining method innovated by Tianchen coal mine. 本文介绍了田陈煤矿创新的综采与普机采混合、工作面超长布置、对拉、旋转调采、矩形和梯形不规则形状的薄煤层开采技术； cnki