A four - grade pore structure model was brought forward for the first time, while all the previous structure models were evaluated.
首次提出了分四级描述的结构模型，评价并总结了前人所提出的结构模型。
2
The first aspect expresses the relationship between the structure pattern and grade variation of an indication which is called relative difference of weight values of the indication.
第一方面表征一个标志的构形与等级变化之间的关系，称为标志权相对差。
3
During mathematics learning of the firstgrade junior middle school students, it can foster students' varied mathematical abilities by cultivating good cognitive structure mathematics.