1Study on Safe Direct Combustion Technology of Low-concentration GasZHAO Xusheng, PANG JinlunTest Research1-5,162PIV Experiment and Numerical Simulation on Boundary of Recirculation Zone in Sudden Expansion RoadwayWANG Dong, LIU Jian, SONG Ying, GAO KeTest Research6-103Application of AE Technique in Coal and Gas Outburst PredictionCHEN Yutao, QIN Jun, LI Jiangong, ZHANG MingmingTest Research11-164Experimental Study of Forchheimer' s Non-Darcy Seepage of Gas-containing CoalFAN Penghong, NIE BaishengTest Research17-20,245Test Study on Dynamic Water Grouting Sedimentary Pressure Characteristics and Grouting EffectLI Jinhua, SUN Guanlin, SU Peili, GU ShuanchengTest Research21-246Experimental Study on Effect of Thermodynamic Characteristics of Gas Adsorption of Coal Samples with Different Particle SizesLI Xiaojiang, WEI Wenbin, JIA Yongyong, BAI Yang, LOU FangTest Research25-307Research on Roof Stability Control and Countermeasures of Weak Thick Coal Seam in Large Section RoadwayXIAO Dan, ZHAO EnbiaoTest Research31-35,588Design and Implementation of Prediction Analysis System for Coal Mining Subsidence Based on GISWU Mengmeng, MA Lei, ZHAO Weidong, QIAN Jiazhong, HE Xiaorui, ZHAO JitangApplication Techniques36-409Study and Application of Surface Hydraulic Fracturing Technology for Permeability Improvement in Coal MineFU JunhuiApplication Techniques41-4410Study on Optimization of Regional Outburst Prevention Measures for First Mining Face of Outburst SeamLIU Jun, LI Ning, LIU JianyuanTechnical Experience45-48,5311Test Study on Effective Extraction Radius of Hydraulic Flushing HolesWANG Feng, TAO Yunqi, JI KaiTechnical Experience49-5312Study on Critical Value of Inspection Index of Gas Pre-drainage Effect in Three-soft Seam in West Henan Coal FieldGAO JunweiTechnical Experience54-5813Fire Prevention and Extinguishing Technology by Pressure Relief and Balance Ventilation in Coal Mine with Diagonal Ventilation NetworkZHANG Weiliang, ZHANG ChunhuaTechnical Experience59-61,6514Optimization of Double-gateway Bundle Tube Monitoring Technology and Division of "Three Zone" in Gob of Ruian Coal MineSHEN Zhiyuan, QI Qingjie, ZHANG Haiyang, GUO XiaotianTechnical Experience62-6515Study on Deformation Control of Roadway Surrounding Rock in Non-uniform Stress FieldLIU HailongTechnical Experience66-6916Slow Decarburization Reform of Coal Mine Wastewater Based on Three-impulse PID ControlLI Dong, HOU Yuanbin, WANG Chao, HELiuTechnical Experience70-73,7817Research Status and Development Direction of Plugging Technology for Gas Drainage Hole in Coal MineZHOU JunReview and lssue Discussion74-7818Discussion on Surface Exploitation and Utilization Trend of Coalbed MethaneYAO Chenglin, XIONG Yunwei, SONG ChunxiangReview and lssue Discussion79-8219Study on Influencing Factors of permeability of Coalbed Methane ReservoirWANG Chenjun, DU Jingguo, LIANG YinghuaReview and lssue Discussion83-87,9120Research Status and Progress of Diffusion Characteristics of Gas from Coal ParticlesXIANG Yanbin, CHENG Bo, HE FuquanReview and lssue Discussion88-91 