My name is Dashen Yan (in Chinese：严大燊). I am a fourth year Phd student at Mathematics Department, Stony Brook University. My advisor is Claude LeBrun. I am intersted in the special holonomy and related problem. I am currently working on the geometric structure near the singular fibers under the adiabatic limit along some special fibrations (e.g. holomorphic fibration on Calabi-Yau manifolds and Kovalev-Lefschetz fibration on G2 manifolds).