说明：  牛人Matthew Pais，精通扩展有限元、abaqus、matlab,此博士论文详尽描述了XFEM的理论与编程思想。
(Professor Matthew Pais who is proficient at Extended Finite Element、abaqus, matlab。This paper describes the the XFEM theory and matlab programm ideas in detail.Now it is open to you ,my friends!)