Let R be an associative（not necessary commutative） ring. In this paper,we give some properties of Hom-faithful and Hom-cofaithful R-modules. We investigate Σ-self-orthogonal R-modules and P_C-projective dimensions, and give a characterization when the inequality P_C-pd V max{P_C-pd U, P_C-pd W } is strict for an exact sequence 0 → U → V → W → 0. Dually, we study Π-self-orthogonal modules and IC-injective dimensions, and give a similar characterization when... 

【文章來源】：數(shù)學(xué)季刊(英文版). 2020,35(02)

【文章頁數(shù)】：8 頁


本文編號(hào)：3014548