LOM defines a Base schema that defines a hierarchy of data elements for learning objects metadata.

LOM定义了一个基本模式，这个模式为学习对象元数据定义了数据元素的层次结构。

youdao

This extended use of the execution flow notation is motivated by the need to provide a hierarchy of data representation, which is necessary for large-scale, distributed traces.

这种扩展的主要原因是在大型分布式应用程序的跟踪时需要提供分层次的数据表示形式。

youdao

Using the XML data model, the whole hierarchy of data object wrappers can be eliminated, leaving the programmer to focus on the business logic rather than on the business data management.

通过使用XML数据模型，就可以取消整个数据对象包装器层次结构，让开发人员将注意力集中在业务逻辑上，而不会为业务数据管理分心。

youdao

Data is at the base of a hierarchy of understanding.

FORBES: Moving from Big Data to Big Wisdom

There is a distinct hierarchy in the strength of evidence provided by these three sources of data.

FORBES: Clinical Trial Advice For Investors From Two Pros