1. Forestry and Forest Products Research Institute, 1 Matsunosato, Tsukuba, Ibaraki 305-8687, Japan
2. Kyushu Research Center, Forestry and Forest Products Research Institute, 4-11-16 Kurokami, Chuo-ku, Kumamoto, Kumamoto 860-0862, Japan
3. Graduate School of Technology, Industrial and Social Science, Tokushima University, 2-1 Minami-josanjima, Tokushima 770-8513, Japan