University of MaraghehSahand Communications in Mathematical Analysis2322-580715120190701Approximate Duals of $g$-frames and Fusion Frames in Hilbert $C^ast-$modules1351463572610.22130/scma.2018.81624.396ENMortezaMirzaee AzandaryaniDepartment of Mathematics, University of Qom, Qom, Iran.Journal Article20180216In this paper, we study approximate duals of $g$-frames and fusion frames in Hilbert $C^ast-$modules. We get some relations between approximate duals of $g$-frames and biorthogonal Bessel sequences, and using these relations, some results for approximate duals of modular Riesz bases and fusion frames are obtained. Moreover, we generalize the concept of $Q-$approximate duality of $g$-frames and fusion frames to Hilbert $C^ast-$modules, where $Q$ is an adjointable operator, and obtain some properties of this kind of approximate duals.https://scma.maragheh.ac.ir/article_35726_cc21d1f5aa898076fe219206175ae0ca.pdf