1Study on the migration law of pressure relief gas based on dynamic evolution model of goaf porosityZHANG Yongtao, ZHU Pengfei, LI Qingzhao, DOU Chengyi, DU HaohaoTest Research1-62Study on key technology of surrounding rock reinforcement in strong mining roadway of Shanjiaoshu Coal MineZHENG Hanghang, MA Zhenqian, LIANG XuchaoTest Research7-13,203Load and permeability evolution law of lower layering in upper slicing of inclined extra-thick coal seamLU Fangchao, ZHANG Xuebo, GAO JianliangTest Research14-204Study on fault mining activation of lower-group coal floor and numerical simulation of fluid-solid couplingYAN Meixin, ZHU Shuyun, ZHANG Min, ZHANG ZhenguoTest Research21-275Experimental research on compound inhibition of spontaneous combustion of coal gangue hillXU Jingjing, ZHANG Jiwei, MO Fan, ZHU QiTest Research28-326Optimization design of sludge paste filling material ratio based on RSMLIU Yin, CHEN Sen, MA Jiyan, HU Wenjing, WANG HaoyuTest Research33-39,457Study on the flame retardant property of reactive halogen-free organic grouting reinforcement materials for coal minesCHEN Xingming, ZHOU Ting, ZHOU Jiajia, MA Lin, LIU Qing, XU XiangbinTest Research40-458Mesoscopic simulation of horizontal grouting in weakly cemented sand gravel layerLIU Shujie, XIE Zuodong, ZHANG Jiwei, AN XuliangTest Research46-519Study on pyrolysis kinetic parameters of coal mine transport beltZHANG Duo, LIU Maoxia, HU Shaoping, WANG Zhenping, SONG Xianming, WANG WeifengTest Research52-5810Numerical simulation of cyclone separation technology for dry drilling dust removalXING Pengchao, LU Ke, YANG Yongbo, ZHANG Biao, YI JunTest Research59-63,7011Design of gas concentration prediction and early warning system for outburst accident based on LSTMLAN Haiping, ZHANG Zhigang, XU Zaigang, TIAN Xianggui, ZHANG ShaochaoDevelopment Design64-7012Development and application of simulation experimental equipment for coal stress measurement while drillingZHANG Kai, LIU Guangwei, ZHAO Zhigang, ZHENG YahuaDevelopment Design71-7613Prediction model of mining subsidence of coal mine in Jincheng mountain areaNIU Haijun, CAI Lailiang, WEI Peng, ZHAO Junwei, KANG HongyueTechnical Experience77-8114Identification and positioning method of mine external fire based on machine vision and grey modelLI Guangyu, LI Shoujun, MIAO YanziTechnical Experience82-8715Research on catastrophic law of delayed gushing water from subsided karst collapse column in the open-off cut blasting excavationYANG Hongfei, WANG WenzhenTechnical Experience88-9216Research and application of downward long drilling technology in large inclined broken soft and low-permeability coal seamZHAO Kun, LIU PeiTechnical Experience93-9617Study on the width of stress-relaxed area for pressure-relief of outburst coal seam in gob-side entry drivingZHOU Zhongli, ZHANG Shuai, YANG Shengqiang, TANG Hongqiang, SONG Wanxin, BAI YanlongTechnical Experience97-102,10818Theory and application of comprehensive detection of water-rich floor in 13103 working faceZHAO Jianwei, DUAN Chunsheng, GAO LinshengTechnical Experience103-10819Drainage-weathering damage rule of thick coal seam and micro-blasting control technology of coal wall rib spallingGUO JingTechnical Experience109-11320Research on causal factors of coal mine gas explosion based on DEMATEL-ISM-MICMACGUO Huimin, CHENG Lianhua, LI ShugangIssue Discussion114-119 