可自动从ＯＲＡＣＬＥ数据库中提取产品零部件信息，构成产品结构树，同时，可查看任务分配／完成情况／用户管理等．-automatically from the ORACLE database information extraction product components, product structure tree pose the same time, can View assignment / completion of the / user management.

交流电桥的电路结构中，由电阻、电抗元件或 它们的组合构成四臂，并用检流计、耳机或其它仪器作为检验电桥是否平衡的“示零器”．利用交流电桥的平衡条件进行测量，这就是它的基本原理．-AC bridge circuit structure, resistance, reactance components or combinations of them pose four arm and used galvanometers. headphones or other equipment -- as