万方数据库使用布尔逻辑算符anD./or/not.其中A.anD.B表示（）。

为了减小变流电路的开、关损耗，通常让元件工作在软开关状态，软开关电路种类很多，但归纳起来可分为（）、（）两大类。

为了减小变流电路的开、关损耗，通常让元件工作在软开关状态，软开关电路种类很多，但归纳起来可分为（）、（）两大类。根据软开关技术发展的历程分为（）、（）、（）三类软开关电路。

可以在（）阶段采用Make-or-buy决策分析。

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。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

布尔逻辑具体检索时，是通过三个布尔运算符来实现其功能的：AND、OR、（）。