Affiliation: | aInstitute of Scientific Research, Oita University, 700 Dannoharu, Oita 870-1192, Japan;bFaculty of Engineering, Oita University, 700 Dannoharu, Oita 870-1192, Japan;cOita Industrial Research Institute, 1-4861-10 Takae-nishi, Oita 870-1117, Japan |