1. Department of Agricultural Engineering, Kyungpook National University, Daegu 702-701, Korea
2. Department of Horticulture Environment System, Korea National College of Agriculture and Fisheries, 1515, Kongjwipatjwi-ro, Deokjin-gu, Jeonju-si, Jeollabuk-do 54874, Republic of Korea
3. Institute of Agricultural Science & Technology, Kyungpook National University, Daegu 702-701, Korea