音(Ton)
桥式可逆PWM变换器给直流电动机供电时采用双极性控制方式,其输出平均电压等于( )。A、Ud=(ton/T-1)B、Ud=(2ton/T-1)C、Ud=Uston/TD、Ud=2Uston/T
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下列数组声明正确的是( )A.Dima(1ton)AsIntegerB.Dima(10)AsInteger:ReDima(1to12)C.Dima()AsInteger:ReDima(3,4)AsIntegerD.Dima()AsInteger:ReDima(1ton)AsInteger
以下匹配'1 ton'和'2 ton'及'3 ton'的正则表达式是( )A.'123 ton'B.'1,2,3 ton'C.'[123] ton'D.'1|2|3 ton'
______ cargoes chargeable at the same rate,part of one ton shall be taken as one ton.A.AtB.ForC.OnD.About
Which wire rope purchases may be used with a 30-ton pedestal crane ________.A.HoistB.LuffC.Rider blockD.All of the above
The expedition reached the summit at 10:30 that morning.A:bottom of the mountain B:foot of the mountain C:staring point D:ton of the mountain
下料皮带运输机能力为()。A、30ton/hrB、20ton/hrC、10ton/hr