1. Department of Healthcare Engineering, Jeonbuk National University, Jeonju-si, Republic of Korea
2. Research Center, Color Seven Co., Ltd., Seoul, Republic of Korea
3. Division of Biomedical Engineering, Jeonbuk National University, Jeonju-si, Republic of Korea
4. Research Center of Healthcare and Welfare Instrument for the Aged, Jeonbuk National University, Jeonju-si, Republic of Korea