As a social media, online social networks play a vital role in the social
information diffusion. However, due to its unique complexity, the mechanism of
the diffusion can be different from the ones in other types of networks and
remains unclear to us. Meanwhile, few works have been done to reveal the
coupled dynamics of both the structure and the diffusion of online social
networks. To this end, in this paper, we propose a model to investigate how the
structure is coupled with the diffusion in online social networks from the view
of weak ties.