Supported by the Specialized Research Fund for the Doctoral Program of Higher Education (20060286006);the FNS of CHINA(10571026);the Southeast University Fund(XJ0707273)
The National Natural Science Foundation of China(No10626012), Jiangsu Planned Projects for Postdoctoral ResearchFund(No0502022B)
Let S be a semigroup and let A be an S-act. Some necessary and sufficient conditions that S-subacts of A are maximal S-subacts are given. A relation B which is similar to the Green relation in semigroups is defined. B...