Quasi-injective reductions

Generalizations of principally quasi-injective modules and quasiprincipally injective modules

LetR be a ring andM a rightR-module with S= End(MR). The moduleM is called almost principally quasi-injective (or APQ-injective for short) if, for any m∈M, there exists an S-submodule Xm of M such that lMrR(m) = Sm ⊕ Xm. The module M is called almost quasiprincipally injective (or AQP-injective for short) if, for any s∈ S, there exists a left ideal Xs of S such that lS(ker(s)) = Ss ⊕ Xs. In thi...

Fp-injective and Weakly Quasi-frobenius Rings

The classes of FP -injective and weakly quasi-Frobenius rings are investigated. The properties for both classes of rings are closely linked with embedding of finitely presented modules in fp-flat and free modules respectively. Using these properties, we characterize the classes of coherent CF and FGF-rings. Moreover, it is proved that the group ring R(G) is FP -injective (weakly quasi-Frobenius...

Structure of Fp-injective and Weakly Quasi-frobenius Rings

In the present paper new criteria for classes of FP -injective and weakly quasi-Frobenius rings are given. Properties of both classes of rings are closely linked with embedding of finitely presented modules in fp-flat and free modules respectively. Using these properties, we describe classes of coherent CF and FGF-rings. Moreover, it is proved that the group ring R(G) is FP -injective (resp. we...

The Ultra-Quasi-Metrically Injective Hull of a T 0-Ultra-Quasi-Metric Space

Space Reductions for Model Checking Quasi-Cyclic Systems

Despite significant research on state-space reductions, the poor scalability of model checking for reasoning about behavioral models of large, complex systems remains the chief obstacle to its broad acceptance. One strategy for making further progress is to exploit characteristics of classes of systems to develop domain-specific reductions. In this paper, we identify a structural property of sy...