Funding for this research was provided by:
Incheon National University (Research Grant in 2016)
Article History
Received: 18 June 2017
Accepted: 11 September 2017
First Online: 21 September 2017
Compliance with ethical standards
:
: Authors Sun Young Jung, Yun Joo Chyung, and Pyoung Won Kim declare that they have no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors.