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。

埋弧焊的焊接方法代号是（）。

常用的焊接方法中手弧焊的焊接方法代号是（）。

等长双头螺柱的代号是（）

什么是螺柱焊？螺柱焊有哪些特点？

影响螺柱焊质量的主要焊接参数有，下列不正确的是（）

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。