9MacQueenJ. Some Methods for Classification and Analysis of Multivariate Observations [C]. In: Proceed- ings of the 5th Berkeley Symposium on Mathematical Statistics and Probability. Berkeley, University of Cal- ifornia Press, 1967: 281-297.
10Chiang M L. Efficient diagnosis protocol to enhance the reliability of a cloud computing environmentFJ]. Journal of network and sys terns management, 2012,20(4) : 579-600.
