To reduce high complexity in extraction of functional regularity in digital ICs,a template called CHAIN generation algorithm is proposed based on data mining.Weights of edges are encoded,and a complex subcircuit isomorphism problem is solved by comparing edge weight sequences of the subcircuit.To reduce complexity and accelerate the algorithm,a pruning strategy is introduced into expending of templates to delete non-frequent subcircuits gradually.By merging template generation process and subcircuit isomorphism searching process,the regularity extraction flow is simplified.Experiments show that this CHAIN template algorithm is more effective.It obtains better circuit covering result than SPOG and TREE methods.

A method to calculate the symmetry coefficents in quantum chemistry calculation is in-troduced, which is very useful for calculations of complex cluster. Some results of C₆₀ molecule are aslo represented.

A method of improving the convergence in the DV-_α-SCC calculation are studied in the scheme suggested by Broyden. The obtained result reveals that the convegence of SCC calculations is greatly accelerated by our new calculation procedure. This method may improve the problem of relative slow convergence or even non convegent which are usually happened in the DV-_α-SCC calculations for large cluster with low symmetry.