闭合电磁铁电路的开关,两个小磁针迅速摆动后静止(如图示),左边的小磁针左端为N极,则右边静止的小磁针的A端是
A.正极
B.负极
C.S极
D.N极
答案:C
机泵轴承振动值每分钟3000转应不大于()mm。
A、0.05
B、0.06
C、0.07
D、0.08
Due to a constAntly ______ environment, a poor understanding of the user’s needs and preferences,as well as a ______ of willingness to modify ______ organizational structures and decision models,the full economic potential of Web Information Systems(WIS) has not been realized by now. The data object types of the ______ meta model,the Extended World Wide Web Design Technique(eW3DT),provide hypertext designers ______ a conceptual,user-centric framework and graphical notation for the construction of both,______ and customized models, during the software development ______ of commercial WIS. A reference model as a normative concept represents an abstraction of a ______ company,its functional units, or its(Web) Information System and is intended to streamline the design and implementation of complex applications at ______costs. As precondition for pursuing a partial globalization strategy,eW3DT ______ between technical and content-specific responsibilities for designing, implementing, and maintaining WIS.
A.gives
B.distinguishes
C.has
D.difference