[1] Pusan Natl Univ, Dept Precis Mech Engn, Pusan 609735, South Korea
[2] Pusan Natl Univ, Sch Mech Engn, Pusan 609735, South Korea
[3] Pusan Natl Univ, Engn Res Ctr NSDM, Pusan 609735, South Korea
[4] Pusan Natl Univ, Dept Nanosyst Proc Engn, Pusan 609735, South Korea