Any empty header, such as Meta-Persistence above, must include a single space after the colon.

任何空白头部，比如上面提到的Meta - Persistence，必须在冒号之后包含一个空格。

The classification results of basis classifiers were added to original feature vector to obtain the meta-level data, which enhanced the search ability in hypothesis space and decreased system bias.

通过扩展特征向量，元学习增强了对假设空间的表达能力，降低了系统的偏差。

Finally, the paper proposed a space metadata management framework and initially realized the parts of function of the meta-database management.

最后，论文提出了一个空间元数据管理系统的总体设计框架，并初步实现空间元数据库的管理和检索功能。