比较单频率与双频率载波通道的纵联距离保护和环状与链状连接光纤通道的差动保护方案。
It compares the pilot distance protection with power line carrier (PLC) in the single or double frequency and the differential protection with optical fiber in the loop or chain connection.
目的观察腰麻中不同辅助药对脑电双频谱指数(BIS)和边缘频率(SEF)的影响。
Objective To observe the effects of different adjuvants on bispectral index (bis), spectral edge frequency (SEF) of electroencephalogram during lumbar anesthesia.
介绍锻钢冷轧工作辊双频感应淬火设备特点，国内首创较低的中频频率的选定，与同类淬火设备比较的优点。
This paPer introduces the equipments of double-frequency induction heating the forged steel cold work roller, and compare with the same kind induction heating equipments.
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