This paper briefly introduces the design of SDQ-91 directional coring apparatus, selection of SDQ-91 borehole measuring instrument and its improvement.
介绍了SDQ - 91型随钻测量定向取心钻具的特点、定向取心器的研制、随钻测量仪的选型与改进等。
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Methods: 737 middle school students were asked to finish children mental health knowledge questions and The Strengths and Difficulties Questionnaire (SDQ).