【单选题】在已明确所要研究问题的内容与重点后,拟定调研计划,进行实地调查,收集第一手资料,如实地反映情况和问题。这属于( )
【单选题】听力原文: The agricultural revolution in the 19th century involved two things: the invention of labor-saving machinery and the development of scientific agriculture. Labor-saving machinery naturally appea...
A.
The invention of machine that can save labor and the progress of scientific agriculture.
B.
The invention of crude equipments and agricultural implements.
C.
The advance of agriculture machinery and the iron plow.
D.
The idea of a cast-iron plow and steel plow.
【简答题】ZY4A 型电液转辙机副机内的挤脱连接器和 S700K 型电动转辙机内的保持联结器都是 装置
【简答题】There have been many great inventions, things that changed the way we live. The first great invention was one that is still very important today- the wheel. This made it easier to carry heavy things a...
【判断题】ZYJ7型电液转辙机转辙机尖轨与基本轨密贴后,电液转辙机的锁闭柱缺口两侧间隙为2mm±0.5mm。转换锁闭器检查柱缺口两侧间隙为6mm±1.5mm。
【判断题】ZYJ7型电液转辙机电机电源交流380V。
【判断题】ZYJ7型电液转辙机心轨转辙机的检测动程为115mm。
【简答题】对于12号提速道岔(无可动心轨)的尖轨处应设置 台S700K型电液转辙机或 台ZD(J)9型电动转辙机。