二区的啊，一直都是在二区的
结构(Structure) Component抽象类或者接口对应之前例子中的IBox,Leaf对应SingleBox,Composite对应ContainerBox。客户代码只依赖于Component抽象类或者结构,这正是我们期望的目的。 Composite模式的几个要点 Composite模式采用树形结构来实现普遍存在的对象容器,从而将“一对多”的关系转化为“一对一”的关系,使得客户代码可以一致...
aMullite short fiber reinforced Al-4.0Cu-1.85Mg composite and its base alloy were fabricated by squeeze casting. The age-hardening behavior, precipitation procedure, microstructure of dislocation and precipitates, and the interfacial structure have been studied by means of hardness measurement (HB), di...
aSection 2 discusses the requirements of role-based the HIS. In Section 3 we introduce the structure and the elements of the proposed role-based authorization model. Moreover, we present several new notations for authorizations and considerations of different types of services. Section 4 also intro...