频率研究 meaning in English

frequency studies

Frequency of bottom of ultrasonic cleaning basin
超声清洗槽槽底谐频率研究
A frequency study on raindrops impacting on pd fuze
弹头引信碰雨频率研究
Overview of the research on implicit learning in motor skill acquisition
追加反馈的呈现频率研究综述
Accident reason and frequency research in dangerous chemicals road transport
危险化学品公路运输事故原因及发生频率研究