[1] Korea Natl Univ Transportat, Dept Polymer Sci & Engn, Chungju 380702, South Korea
[2] Korea Natl Univ Transportat, Dept Chem & Biol Engn, Chungju 380702, South Korea
[3] Korea Natl Univ Transportat, Dept Elect Engn, Chungju 380702, South Korea
[4] Korea Natl Univ Transportat, Dept IT Convergence Brain Korea PLUS 21, Chungju 380702, South Korea