that defines a hierarchy of data elements for learning objects metadata ,这个模式为学习对象元数据定义了数据元素的层次结构。
create the individual tables to represent the different hierarchies of data that your xml represents 创建表示xml所代表的数据的不同层次结构的各个表。
the model includes the hierarchy of data sharing, the hierarchy of land resources information service and the hierarchy of decision support . the structure of land resources information service system is introduced in logic model . at the same time, the paper discusses the factor that influences the construction of land resources information system 然后提出了国土资源信息服务系统建设的层次模型,包括数据共享层、国土资源信息服务层和决策支持层;从逻辑模型的角度介绍了国土资源信息服务体系结构,在此基础上讨论了影响信息服务体系建设的主要因素。