Funding for this research was provided by:
National Research Foundation of Korea (NRF-2019R1A2C2006915)
National Research Foundation of Korea (NRF-2017R1A4A1015620)
Rural Development Administration (PJ01314501)
Article History
Received: 6 January 2020
Revised: 10 February 2020
Accepted: 19 February 2020
First Online: 9 March 2020