%0 Journal Article
%T 相对于理想的环的刻画<br>Characterizations of rings relative to an ideal
%A 王永铎
%A 何健&lt
%A br&gt
%A WANG Yong-duo
%A HE Jian
%J 山东大学学报（理学版）
%D 2017
%R 10.6040/j.issn.1671-9352.0.2016.432
%X 摘要： 设I是环R的理想, 引入伪半投射I-盖的概念。 证明了每一个左R-模有伪半投射I-盖当且仅当每一个左R-模有投射I-盖, 并证明了伪半投射模构成的类是投射类, 进而推广了一些已有的结论。<br>Abstract: Let I be an ideal of a ring R. The concept of pseudo semiprojective I-covers is introduced. It is shown that every left R-module has a pseudo semiprojective I-cover if and only if every left R-module has a proj-ective I-cover. It is also proved that the class of all pseudo semiprojective modules is a projectivity class, and then some well known results are generalized
%K 半完备环
%K 半正则环
%K 伪半投射摸
%K 投射类
%K &lt
%K br&gt
%K semiregular ring
%K pseudo semiprojective module
%K semiperfect ring
%K projectivity class
%U http://lxbwk.njournal.sdu.edu.cn/CN/10.6040/j.issn.1671-9352.0.2016.432