  We describe a new framework of a sublinear expectation space and the related
notions and results of distributions, independence. A new notion of
G-distributions is introduced which generalizes our G-normal-distribution in
the sense that mean-uncertainty can be also described. W present our new result
of central limit theorem under sublinear expectation. This theorem can be also
regarded as a generalization of the law of large number in the case of
mean-uncertainty.
