【简答题】Today, there are more than 20 Beidou satellites above our heads, and China plans to send up even more this year to expand(扩张)the Beidou network to better serve the Belt and Road Initiative. As Beidou ...
【判断题】《人民日报》在1961年上半年曾开辟“笔谈杂文”专栏。
【单选题】TN-S系统是指电力系统中性点直接接地,整个系统的中性线与保护线是()。
【判断题】TN-S系统是指电力系统中性点直接接地,整个系统的中性线与保护线是合一的。( )
【单选题】What will make Beidou competitive with the US Global Positioning System?
A.
It is benefiting civilians and the military.
B.
It has been providing accurate and stable services.
C.
It has improved its accuracy to an error margin as low as five meters.
D.
Its accuracy can be further improved to be within centimeters.
【单选题】除租用机房外,三相电缆线线径应不小于()mm 2 。
【多选题】BeiDou卫星导航系统建设过程遵循( )原则。
【单选题】供电系统中有一部分线路的中性线与保护零线是合一的,另一部分中性线与保护零线是分开的系统是( )。
【单选题】TN系统中,系统中有一部分中性线与保护线是合一的系统称为: