Wang, Lijin
Yin, Yilong
Zhong, Yiwen
Article History
Received: 17 April 2014
Accepted: 21 January 2015
First Online: 6 June 2015
Change Date: 18 April 2016
Change Type: Erratum
Change Details: In this article, the bracket in the denominator of Eq. (6) is incorrect.