Kim, Guang Hwi
Lee, Hee Sung
Jung, Sung Won
Lee, Jae Gwang
Lee, June Hee
Lee, Kyung Jae
Kim, Joo Ja
Article History
Received: 31 March 2017
Accepted: 22 February 2018
First Online: 12 March 2018
Competing interest
: The authors declare that they have no competing interests.
: We obtain ethical approval from the institutional review board (IRB Approval No. SCHUH 2017–01-029) at Soonchunhayang university.
: Not applicable.
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