The enumeration problem of round-robin tournaments and perfect matchings are discussed.

The concept of determining round-robin tournaments of order 4n by using existed round-robin tournament with Δ(G) indicated perfect matchings is described.

By defining a special transformation, we obtain an interesting property about the set of perfect matchings of hexagonal systems, that is, any two perfect matchings can be transfered by a series of the defined transformations.

Minimum degree distance of unicyclic graphs with perfect matching;

On the second largest Laplacian eigenvalues of trees with nearly perfect matchings;

Enumeration of perfect matchings in some type polyminoes;

The tracing algorithms for complete matching of bipartite graph;

The use of perfectly matched layer (PML) in cylindrical coordinates avoids the wasted computation.

Nowadays, the perfectly matched layer (PML) ABC has proven to be the most efficient technique.

Absorbing boundary condition for acoustic wave equation by perfectly matched layer;

Improved algorithm for absorbing boundary condition of acoustic perfectly matched layer

An anisotropic-medium(unsplit) perfectly matched layer(PML) absorbing boundary condition is presented for the truncation of FDTD lattices with general lossy and dispersive media.