Using the domain derivative of the far-field pattern for eddy-current inverse problem with Dirichlet boundary condition,a new algorithm to recover the shape of cracks was constructed and some numerical examples were given.

Eddy current inverse technique is very important method to the reconstruct the shape of crack In this paper, using the domain derivative of farfield pattern for eddy current inverse problem with Dirichlet boundary condition, a new algorithm to recover the shape of crack is constructed and some numerical some examples are given, which demonstrate that the algorithm is feasible and correc

In this paper,the domain derivative of the far-field pattern blended boundary condition is introduced,a new algorithm to recover the boundary shape is constructed and some numerical examples are given.

The main strategies to implement digital region according to the situation in now days China are put forward.

Digital region has very important value and future in application,which is the significant part of Digital Earth.

To figure out some basic problems in current digital region construction, this paper puts forward the concept of digital region application infrastructure (DRAI), and analyzes the research background, reference model and application supporting platforms for information sharing.