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Dai Xianchun

 

Dai Xianchun, bachelor's degree holder, a researcher at the Railway Science & Technology Research & Development Center of the China Academy of Railway Sciences Corporation Limited, is mainly engaged in railway safety engineering. His achievements are the research projects and technical services in the fields of railway safety technology, safety management, RAMS management, accident analysis, high-speed railway disaster prevention monitoring, railway risk management, and safety technical standards and regulations. In recent years, he has undertaken or participated in more than 20 scientific research projects at the national, provincial and ministerial levels. He has won many science and technology awards, including 2 first prizes and 1 second prize at provincial and ministerial levels and several prizes at CR regional group level, been awarded 3 patents for invention, and published 12 academic papers. 

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   又黄又爽又色又刺激的视频,性色AV浪潮AV色欲AV,最新热播电视剧全集在线观看,a级毛片内射免费视频,亚洲欧美无人区乱码