Tao Yang, Yan-Hui Chen, Ya-Chao Wang, Wei Ou, Lei-Ying Ying, Yang Mei?, Ai-Qin Tian, Jian-Ping Liu?, Hao-Chung Kuo, Bao-Ping Zhang?

In this article the author’s name “Hao-Chung Kuo” was incorrectly written as “Hao-Chung Guo”.

And in the last sentence of the first paragraph of Introduction, the text ‘(20-20)’ should have read ‘(20-21)’.The original article has been corrected.

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