For each domain model concept, an individual overlay model stores some value which is an estimation of the user knowledge level of this concept.

对于每个领域模型中的概念，单个的叠加模型中都存储了用户对这个概念的认知程度的评价值。

youdao

For each domain model concept, an individual overlay model stores some value which is an estimation of the user knowledge level of this concept.

对于每个领域模型中的概念，单个的叠加模型中都存储了用户对这个概念的认知程度的评价值。

youdao