6Allareddy V, Havens AM, Howell TH, et al. Evaluation of a new assessment tool in problem-based learning tutorials in dental education [ J]. J Dent Educ ,2011,75 (5) :665-671.
7F R Adler,BNuemberger.Persistence in patchy irregular landscapes[J].Theoretical Population Biology,1994,45:41-75.
8S Bandini,G Mauri,R Serra.Cellular automata:From a theoretical parallel computational model to its application to complex systems[J].Parallel Computing,2001,27:539-553.
9C G Langton.Studying artificial life with cellular automata[J].Physica D,1986,22:120-149.