1. Institute of Agricultural & Life Science, Gyeongsang National Univ., Jinju 660-701, Korea
2. Dept. of Bio-Industrial Machinery Eng., Gyeongsang National Univ. (Insti. of Agric. & Life Sci.), Jinju 660-701, Korea
3. Korea Infrastructure Safety & Technology Corporation, Goyang 411-758, Korea
4. Dept. of Agricultural Eng., Gyeongsang National Univ. (Insti. of Agric. & Life Sci.), Jinju 660-701, Korea