9Kennedy J,Eberhart R. A new optimizer using particle swarm theory[C]//Proceedings of the Sixth International Symposium on Micromachine and Human Science. Piscataway, NJ: IEEE Service Center, 1995:39-43.
10Wang Fengxiao.Improvement on unequal interval gray forecast model[J].Fuzzy Information and Engineering,2006,6(1),118-123.