MOS控制晶闸管（MCT）是新型电力电子器件，它具有（）特点。

试列举你所知道的电力电子器件，并从不同的角度对这些电力电子器件进行分类。目前常用的控型电力电子器件有哪些？

晶闸管是（）电力器件

Every deliberate act of wrongdoing by the master or any of the crew against the ship or cargo，without the authorization or privity of the Shipowner or his agent，is（）.

（）, or drum is used for hauling in or letting out the wires or ropes which will fasten the ship to the shore.

A salvor may be（）the whole or part of the payment due under Salvage Convention to the extent that the salvage operations have become necessary or more difficult because of fault or neglect on his part or if the salvor has been guilty of fraud or other dishonest conduct.

The （） is used for hauling in or letting out the wires or ropes.

Vessels must be（）valid certificate of nationality or certificated of registry or license.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

电力电子器件是构成变频器的关键器件之一。下列电力电子器件中属于半控型器件的是（）

普通晶闸管（SCR）及其大部分派生器件不属于半控型电力电子器件。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。