中文摘要：

通过效应代数中的中心元引入效应代数中的Well Inside关系，研究了效应代数中的Well Inside关系的性质；在此基础上得出了效应代数成为布尔代数的一个充要条件。

英文摘要：

The relationship of Well Inside in effect algebra is introduced by the center elements of effect algebra, and the proper-ties of the relationship of Well Inside are studied. Based on the relationship of Well Inside, a necessary and sufficient condition which effect algebra becomes Boole algebra has been obtained.