in this paper,  we determine necessary and sufficient tauberian conditions under which convergence in pringsheim's sense of a double sequence of fuzzy numbers follows from its $(c,1,1)$ summability. these conditions are satisfied if the double sequence of fuzzy numbers is slowly oscillating in different senses. we also construct some interesting double sequences of fuzzy numbers.

Phase measurement is a long-standing challenge in a wide range of applications, from X-ray imaging to astrophysics and spectroscopy. While in some scenarios the phase is resolved by an interferometric measurement, in others it is reconstructed via numerical optimization, based on some a-priori knowledge about the signal. The latter commonly use iterative algorithms, and thus have to deal with t...