Based on both various careers regarding to track design and research & development of rail track technology, Seohyun has been executed successfully a lot of large scales domestic and overseas projects such as "basic design for electrical railroad bed of Jungang line Dodam-Yeongcheon double track", "the Ivory Coast Abidjan metropolitan rapid transit construction project". Also, Seohyun has been participating in R&D projects over diverse countries for figuring out the latest rail technology trend and improving advanced technology and skill.