21st TCTAP 2016
Unceasing Change and Evolution
Home > Faculty
Faculty
International Faculty
Invited Faculty
Faculty of the Year
Korean Faculty
Invited Faculty
Faculty of the Year
Download
TCTAP 2017 Press Kit
TCTAP 2016 Final Program
Introduction of CVRF
Like us on facebook
Korean Faculty
** Please search by either first name or last name.
Invited Faculty
 A 
Chul-Min Ahn, MD
Yonsei University Severance Hospital
Korea (Republic of)
Hyuk Ahn, MD
Veterans Health Service Medical Center
Korea (Republic of)
Jung-Min Ahn, MD
Asan Medical Center
Korea (Republic of)
Taehoon Ahn, MD
Korea University Anam Hospital
Korea (Republic of)
Youngkeun Ahn, MD
Chonnam National University Hospital
Korea (Republic of)
 B 
Byeong Joo Bae, MD
Konkuk Univrsity Medical Center
Korea (Republic of)
Jae Seok Bae, MD
Gyeongsang National University Changwon Hospital
Korea (Republic of)
Jang-Ho Bae, MD
Konyang University Hospital
Korea (Republic of)
Jang-Whan Bae, MD
Chungbuk National University Hospital
Korea (Republic of)
Sora Baek, MD
Kangwon National University Hospital
Korea (Republic of)
 C 
Dong Hoon Cha, MD
CHA Bundang Medical Center, CHA University
Korea (Republic of)
Kwang Soo Cha, MD
Pusan National University Hospital
Korea (Republic of)
In-Ho Chae, MD
Seoul National University Bundang Hospital
Korea (Republic of)
Jei Keon Chae, MD
Chonbuk National University Hospital
Korea (Republic of)
Byung Chul Chang, MD
CHA Bundang Medical Center, CHA University
Korea (Republic of)
Kiyuk Chang, MD
The Catholic University of Korea, Seoul St. Mary’s Hospital
Korea (Republic of)
Mineok Chang, MD
Seoul National University Hospital
Korea (Republic of)
Sang Soo Cheon, MD
Asan Medical Center
Korea (Republic of)
Byung Ryul Cho, MD
Kangwon National University Hospital
Korea (Republic of)
Jang Hyun Cho, MD
St. Carollo Hospital
Korea (Republic of)
Jin-Man Cho, MD
Kyung Hee University Hospital at Gangdong
Korea (Republic of)
Jung Rae Cho, MD
Kangnam Sacred Heart Hospital
Korea (Republic of)
Kyoung Im Cho, MD
Kosin University Gospel Hospital
Korea (Republic of)
Min Soo Cho, MD
Asan Medical Center
Korea (Republic of)
Myeong-Chan Cho, MD
Chungbuk National University Hospital
Korea (Republic of)
Sang-Cheol Cho, MD
Asan Medical Center
Korea (Republic of)
Sung Won Cho, MD
Cheju Halla General Hospital
Korea (Republic of)
Yoon Haeng Cho, MD
Soon Chun Hyang University Bucheon Hospital
Korea (Republic of)
Young Rak Cho, MD
Dong-A University Medical Center
Korea (Republic of)
Yeon Hyeon Choe, MD
Samsung Medical Center
Korea (Republic of)
Byoung Wook Choi, MD
Severance Hospital
Korea (Republic of)
Byoung-Joo Choi, MD
Ajou University Hospital
Korea (Republic of)
Cheol Ung Choi, MD
Korea University Guro Hospital
Korea (Republic of)
Donghoon Choi, MD
Yonsei University Yongin Severance Hospital
Korea (Republic of)
Hanul Choi, MD
Asan Medical Center
Korea (Republic of)
Hyo-In Choi, MD
Asan Medical Center
Korea (Republic of)
In-Cheol Choi, MD
Asan Medical Center
Korea (Republic of)
Jae Woong Choi, MD
Eulji University Hospital
Korea (Republic of)
Jae Young Choi, MD
Severance Hospital
Korea (Republic of)
Jin-Ho Choi, MD
Samsung Medical Center
Korea (Republic of)
Kee-Joon Choi, MD
Asan Medical Center
Korea (Republic of)
Seung Hyuk Choi, MD
Samsung Medical Center
Korea (Republic of)
Si Wan Choi, MD
Chungnam National University Hospital
Korea (Republic of)
So-Yeon Choi, MD
Ajou University Hospital
Korea (Republic of)
Young Jin Choi, MD
Sejong General Hospital
Korea (Republic of)
Yu Jeong Choi, MD
Eulji University Hospital
Korea (Republic of)
Yunseok Choi, MD
The Catholic University of Korea, Yeouido St. Mary's Hospital
Korea (Republic of)
Suk Jung Choo, MD
Asan Medical Center
Korea (Republic of)
Kook-Jin Chun, MD
Pusan National University Yangsan Hospital
Korea (Republic of)
Cheol Hyun Chung, MD
Asan Medical Center
Korea (Republic of)
Namsik Chung, MD
Severance Hospital
Korea (Republic of)
Woo Young Chung, MD
Seoul National University Boramae Medical Center
Korea (Republic of)
Wook Sung Chung, MD
The Catholic University of Korea, Seoul St. Mary’s Hospital
Korea (Republic of)
 D 
Joon-Hyung Doh, MD
Inje University Ilsan Paik Hospital
Korea (Republic of)
 E 
Lucy Youngmin Eun, MD
Gangnam Severance Hospital
Korea (Republic of)
 G 
Choong Won Goh, MD
Chuncheon Sacred Heart Hospital
Korea (Republic of)
Hyeon-Cheol Gwon, MD
Samsung Medical Center
Korea (Republic of)
 H 
Kee Soo Ha, MD
Korea University Guro Hospital
Korea (Republic of)
Joo-Yong Hahn, MD
Samsung Medical Center
Korea (Republic of)
Jaeyoung Han, MD
Chonnam National University Medical School and Hospit
Korea (Republic of)
Ki Hoon Han, MD
Asan Medical Center
Korea (Republic of)
Kyoo-Rok Han, MD
Kangdong Sacred Heart Hospital
Korea (Republic of)
Jung Ho Heo, MD
Kosin University Gospel Hospital
Korea (Republic of)
Ran Heo, MD
Hanyang University Medical Center
Korea (Republic of)
Bum-Kee Hong, MD
Gangnam Severance Hospital
Korea (Republic of)
Myeong-Ki Hong, MD
Yonsei University Severance Hospital
Korea (Republic of)
Soon Jun Hong, MD
Korea University Anam Hospital
Korea (Republic of)
Taek Jong Hong, MD
Pusan National University Hospital
Korea (Republic of)
Young Joon Hong, MD
Chonnam National University Hospital
Korea (Republic of)
Seung-Ho Hur, MD
Keimyung University Dongsan Medical Center
Korea (Republic of)
Dae Hyun Hwang, MD
Seoul Paik Hospital
Korea (Republic of)
Jin Yong Hwang, MD
Gyeongsang National University Hospital
Korea (Republic of)
Min Su Hyon, MD
Soon Chun Hyang University Seoul Hospital
Korea (Republic of)
 I 
Sang Hyun Ihm, MD
The Catholic University of Korea, Bucheon St. Mary's Hopsital
Korea (Republic of)
 J 
Hwan Jun Jae, MD
Seoul National University Hospital
Korea (Republic of)
Gi Young Jang, MD
Korea University Ansan Hospital
Korea (Republic of)
Jae-Sik Jang, MD
Busan Paik Hospital
Korea (Republic of)
Yangsoo Jang, MD
Yonsei University Severance Hospital
Korea (Republic of)
Sungju Jee, MD
Chungnam National University
Korea (Republic of)
Dong Woon Jeon, MD
National Health Insurance Service Ilsan Hospital
Korea (Republic of)
Hui Kyung Jeon, MD
The Catholic University of Korea, Uijeongbu St. Mary's Hospital
Korea (Republic of)
Myung-Ho Jeong, MD
Chonnam National University Hospital
Korea (Republic of)
Young-Hoon Jeong, MD
Gyeongsang National University Changwon Hospital
Korea (Republic of)
Dongkyu Jin, MD
Soon Chun Hyang University Cheonan Hospital
Korea (Republic of)
Young Soo Jin, MD
Korea Anti-Doping Agency
Korea (Republic of)
Uk Jo, MD
Incheon Sarang Hospital
Korea (Republic of)
Jo Won Jung, MD
Severance Hospital
Korea (Republic of)
 K 
Do-Yoon Kang, MD
Asan Medical Center
Korea (Republic of)
Duk-Hyun Kang, MD
Asan Medical Center
Korea (Republic of)
Hyun-Jae Kang, MD
Seoul National University Hospital
Korea (Republic of)
I-Seok Kang, MD
Samsung Medical Center
Korea (Republic of)
Joon-Won Kang, MD
Asan Medical Center
Korea (Republic of)
Se Hun Kang, MD
CHA Bundang Medical Center, CHA University
Korea (Republic of)
Seung Mo Kang, MD
Chung-Ju Medical Center
Korea (Republic of)
Soo-Jin Kang, MD
Asan Medical Center
Korea (Republic of)
Woong Chol Kang, MD
Gachon University Gil Medical Center
Korea (Republic of)
Hong Ryang Kil, MD
Chungnam National University Hospital
Korea (Republic of)
Byeong-Keuk Kim, MD
Severance Hospital
Korea (Republic of)
Byung Ok Kim, MD
Inje University Sang-gye Paik Hospital
Korea (Republic of)
Chong-Jin Kim, MD
Kyung Hee University Hospital at Gangdong
Korea (Republic of)
Do Hoi Kim, MD
Hyundae UVIS Hospital
Korea (Republic of)
Dong Soo Kim, MD
Busan Paik Hospital
Korea (Republic of)
Dong-Bin Kim, MD
The Catholic University of Korea, Bucheon St. Mary hospital
Korea (Republic of)
Doo Il Kim, MD
Haeundae Paik Hospital
Korea (Republic of)
Eung Ju Kim, MD
Korea University Guro Hospital
Korea (Republic of)
Gi Chang Kim, MD
Konkuk University Chungju Hospital
Korea (Republic of)
Gi-Beom Kim, MD
Seoul National University Children's Hospital
Korea (Republic of)
Gyung-Jung Kim, MD
Gwangmyeong Sungae Hospital
Korea (Republic of)
Hee-Yeol Kim, MD
Bucheon St. Mary’s Hospital
Korea (Republic of)
Hong Jin Kim, Director
Insung Information Co., Ltd.
Korea (Republic of)
Hyo-Soo Kim, MD
Seoul National University Hospital
Korea (Republic of)
Hyun-Sook Kim, MD
Hallym University Sacred Heart Hospital
Korea (Republic of)
Jae-Joong Kim, MD
Asan Medical Center
Korea (Republic of)
Jang Yong Kim, MD
The Catholic University of Korea, Seoul St. Mary's Hospital
Korea (Republic of)
Jeong Hyun Kim, MD
Yangji International Hospital
Korea (Republic of)
Jeongsoon Kim, MD
Asan Medical Center
Korea (Republic of)
Jihoon Kim, MD
Asan Medical Center
Korea (Republic of)
Jin Won Kim, MD
Korea University Guro Hospital
Korea (Republic of)
Ju Han Kim, MD
Chonnam National University Hospital
Korea (Republic of)
Jun Kim, MD
Asan Medical Center
Korea (Republic of)
June Hong Kim, MD
Pusan National University Yangsan Hospital
Korea (Republic of)
Jung-Sun Kim, MD
Yonsei University Severance Hospital
Korea (Republic of)
Kee-Sik Kim, MD
Daegu Catholic University Medical Center
Korea (Republic of)
Kijin Kim, Ph.D
Keimyung University
Korea (Republic of)
Kyung Soo Kim, MD
Hanyang University Hospital
Korea (Republic of)
Min Seok Kim, MD
Asan Medical Center
Korea (Republic of)
Min-Kyu Kim, MD
Bundang Jesaeng hospital
Korea (Republic of)
Minsu Kim, MD
Asan Medical Center
Korea (Republic of)
Moo Hyun Kim, MD
Dong-A University Medical Center
Korea (Republic of)
Myeong Kon Kim, MD
Catholic Kwandong University International St. Marys Hospital
Korea (Republic of)
Pum Joon Kim, MD
The Catholic University of Korea, Seoul St. Mary’s Hospital
Korea (Republic of)
Sang Hyun Kim, MD
Seoul National Univesity Boramae Medical Center
Korea (Republic of)
Sang Hyun Kim
Korea (Republic of)
Sang Wook Kim, MD
Chung-Ang University Hospital
Korea (Republic of)
Seong-Ho Kim, MD
Sejong General Hospital
Korea (Republic of)
Seong-Rim Kim, MD
The Catholic University of Korea, Bucheon St. Mary's Hospital
Korea (Republic of)
Soo-Jin Kim, MD
Yonsei University's Yonjin Severance Hospital
Korea (Republic of)
Soo-Joong Kim, MD
Kyung Hee University Hospital
Korea (Republic of)
Su Hong Kim, MD
Busan Veterans Hospital
Korea (Republic of)
Tae-Oh Kim, MD
Asan Medical Center
Korea (Republic of)
Weon Kim, MD
Kyung Hee University Medical Center
Korea (Republic of)
Won-Jang Kim, MD
CHA Bundang Medical Center, CHA University
Korea (Republic of)
Won-Seok Kim, MD
Seoul National University Bundang Hospital
Korea (Republic of)
Young Hwue Kim, MD
Asan Medical Center
Korea (Republic of)
Young Jo Kim, MD
Yeungnam University Medical Center
Korea (Republic of)
Young-Hak Kim, MD
Asan Medical Center
Korea (Republic of)
Yu Na Kim, MD
Asan Medical Center
Korea (Republic of)
Gi-Young Ko, MD
Asan Medical Center
Korea (Republic of)
Jae-Ki Ko, MD
Heartscan Healthcare
Korea (Republic of)
Young-Guk Ko, MD
Yonsei University Severance Hospital
Korea (Republic of)
Yoon Seok Koh, MD
Hallym University Sacred Heart Hospital
Korea (Republic of)
Bon-Kwon Koo, MD
Seoul National University Hospital
Korea (Republic of)
Chang Hee Kwon, MD
Konkuk University Medical Center
Korea (Republic of)
Hyuck Moon Kwon, MD
Gangnam Severance Hospital
Korea (Republic of)
Oki Kwon, MD
Seoul National University Bundang Hospital
Korea (Republic of)
Osung Kwon, MD
The Catholic University of Korea, Eunpyeong St. Mary's Hospital
Korea (Republic of)
Sung Uk Kwon, MD
Ilsan Paik Hospital
Korea (Republic of)
 L 
Bong-Ki Lee, MD
Kangwon National University School of Medicine
Korea (Republic of)
Bong-Ryeol Lee, MD
Daegu Fatima Hospital
Korea (Republic of)
Byoung Kwon Lee, MD
Gangnam Severance Hospital
Korea (Republic of)
Chang Hoon Lee, MD
Veterans Health Service Medical Center
Korea (Republic of)
Changkun Lee, MD
Hanmaeum Hospital
Korea (Republic of)
Cheol Hyun Lee, MD
Keimyung University Dongsan Medical Center
Korea (Republic of)
Cheol Whan Lee, MD
Asan Medical Center
Korea (Republic of)
Deok Hee Lee, MD
Asan Medical Center
Korea (Republic of)
Han Cheol Lee, MD
Pusan National University Hospital
Korea (Republic of)
Hyoung Doo Lee, MD
Pusan National University Children's Hospital
Korea (Republic of)
Hyunsang Lee, MD
Gumi CHA Medical Center
Korea (Republic of)
Jae Young Lee, MD
The Catholic University of Korea, Seoul St. Mary’s Hospital
Korea (Republic of)
Jae-Hwan Lee, MD
Chungnam National University Hospital
Korea (Republic of)
Jaeseung Lee, MD
Asan Medical Center
Korea (Republic of)
Jeong-Woo Lee, MD
Mokpo Christian Hospital
Korea (Republic of)
Jin Bae Lee, MD
Daegu Catholic University Medical Center
Korea (Republic of)
Jong Min Lee, MD
The Catholic University of Korea, Uijeongbu St. Mary's Hospital
Korea (Republic of)
Jong-Young Lee, MD
Kangbuk Samsung Hospital
Korea (Republic of)
Joon Sang Lee, MD
Good Gang-An Hospital
Korea (Republic of)
Jun-Hee Lee, MD
Kangdong Sacred Heart Hospital
Korea (Republic of)
Keun Lee, MD
Seoul Veterans Hospital
Korea (Republic of)
Nae Hee Lee, MD
Soon Chun Hyang University Bucheon Hospital
Korea (Republic of)
Pil Hyung Lee, MD
Asan Medical Center
Korea (Republic of)
Sang Gon Lee, MD
Ulsan University Hospital
Korea (Republic of)
Sang Hoon Lee, MD
Samsung Medical Center
Korea (Republic of)
Sang-Rok Lee, MD
Chonbuk National University Hospital
Korea (Republic of)
Se-Whan Lee, MD
Soonchunhyang University Cheonan Hospital
Korea (Republic of)
Seung Uk Lee, MD
Kwangju Christian Hospital
Korea (Republic of)
Seung-Hwan Lee, MD
Yonsei University Wonju Severance Christian Hospital
Korea (Republic of)
Seung-Whan Lee, MD
Asan Medical Center
Korea (Republic of)
Sung Yun Lee, MD
Ilsan Paik Hospital
Korea (Republic of)
Woo Seok Lee, MD
YeoSu Jeil Hospital
Korea (Republic of)
Do-Sun Lim, MD
Korea University Anam Hospital
Korea (Republic of)
Hong-Seok Lim, MD
Ajou University Hospital
Korea (Republic of)
Sang Wook Lim, MD
CHA Bundang Medical Center, CHA University
Korea (Republic of)
Sang Yup Lim, MD
Korea University Ansan Hospital
Korea (Republic of)
 M 
Pil-Ki Min, MD
Gangnam Severance Hospital
Korea (Republic of)
Sun-Yang Min, MD
Asan Medical Center
Korea (Republic of)
Keon-Woong Moon, MD
The Catholic University of Korea, St. Vincent's Hospital
Korea (Republic of)
 N 
Deuk-Young Nah, MD
Dongguk University Gyeongju Hospital
Korea (Republic of)
Chang-Wook Nam, MD
Keimyung University Dongsan Medical Center
Korea (Republic of)
Gi-Byoung Nam, MD
Asan Medical Center
Korea (Republic of)
Hyo-Jung Nam, MD
Asan Medical Center
Korea (Republic of)
 O 
Byung-Hee Oh, MD
Mediplex Sejong Hospital
Korea (Republic of)
Dong Joo Oh, MD
Na Eun Hospital
Korea (Republic of)
Jun-Hyok Oh, MD
Pusan National University Hospital
Korea (Republic of)
Seok Kyu Oh, MD
Won Kwang University Hospital
Korea (Republic of)
Seung-Jin Oh, MD
National Health Insurance Service Ilsan Hospital
Korea (Republic of)
Young Keun On, MD
Samsung Medical Center
Korea (Republic of)
 P 
Chang-Bum Park, MD
Kyung Hee University Hospital at Gangdong
Korea (Republic of)
Chul Soo Park, MD
The Catholic University of Korea, Yeouido St. Mary's Hospital
Korea (Republic of)
Duk-Woo Park, MD
Asan Medical Center
Korea (Republic of)
Gyung-Min Park, MD
Ulsan University Hospital
Korea (Republic of)
Hanbit Park, MD
Asan Medical Center
Korea (Republic of)
Hoon Ki Park, MD
Seoul Veterans Hospital
Korea (Republic of)
Hun Sik Park, MD
Kyungpook National University Hospital
Korea (Republic of)
Hyun Woo Park, MD
Soon Chun Hyang University Bucheon Hospital
Korea (Republic of)
Jae Hyoung Park, MD
Korea University Anam Hospital
Korea (Republic of)
Jeong Euy Park, MD
Dr. Park Heart Clinic
Korea (Republic of)
Jino Park
Asan Medical Center
Korea (Republic of)
Jong Seon Park, MD
Veterans Health Service Medical Center
Korea (Republic of)
Jong-Pil Park, MD
Presbyterian Medical Center
Korea (Republic of)
Jong-Seon Park, MD
Yeungnam University Medical Center
Korea (Republic of)
Kyoung-Ha Park, MD
Hallym University Sacred Heart Hospital
Korea (Republic of)
Saejong Park, Ph.D
Korea Institute of Sport Science
Korea (Republic of)
Sang Don Park, MD
Inha University College of Medicine
Korea (Republic of)
Sang Min Park, MD
Hallym University Chuncheon Sacred Heart Hospital
Korea (Republic of)
Sang Woo Park, MD
Konkuk University Medical Center
Korea (Republic of)
Seung-Jung Park, MD
Asan Medical Center
Korea (Republic of)
Si-Hoon Park, MD
Ewha Womans University Mokdong Hospital
Korea (Republic of)
Woo Jung Park, MD
Hallym University Sacred Heart Hospital
Korea (Republic of)
Young-Bae Park, MD
Seoul National University Hospital
Korea (Republic of)
 R 
Seung-Woon Rha, MD
Korea University Guro Hospital
Korea (Republic of)
Jay Young Rhew, MD
Presbyterian Medical Center
Korea (Republic of)
Taegeun Rim, MD
Cheong-Ju Hana Hospital
Korea (Republic of)
 S 
Eak-Kyun Shin, MD
Gachon University Gil Hospital
Korea (Republic of)
Eun-Seok Shin, MD
Ulsan Medical Center
Korea (Republic of)
Doo Sun Sim, MD
Chonnam National University Hospital
Korea (Republic of)
Jae-Kwan Song, MD
Asan Medical Center
Korea (Republic of)
Jin Young Song, MD
Samsung Medical Center
Korea (Republic of)
Jong-Min Song, MD
Asan Medical Center
Korea (Republic of)
Woo Hyuk Song, MD
Korea University Ansan Hospital
Korea (Republic of)
Wook Song, Ph.D
Seoul National University
Korea (Republic of)
Dae Chul Suh, MD
Asan Medical Center
Korea (Republic of)
Jon Suh, MD
Soon Chun Hyang University Bucheon Hospital
Korea (Republic of)
Jung-Won Suh, MD
Seoul National University Bundang Hospital
Korea (Republic of)
 T 
Seung-Jea Tahk, MD
Ajou University Hospital
Korea (Republic of)
 W 
Jongyun Won, MD
Severance Hospital
Korea (Republic of)
 Y 
Dong Hyun Yang, MD
Asan Medical Center
Korea (Republic of)
Han-Mo Yang, MD
Seoul National University Hospital
Korea (Republic of)
Joo-Young Yang, MD
National Health Insurance Service Ilsan Hospital
Korea (Republic of)
Tae-Hyun Yang, MD
Busan Paik Hospital
Korea (Republic of)
Yong-Mo Yang, MD
Cheongju St. Mary's Hospital
Korea (Republic of)
Ki Dong Yoo, MD
The Catholic University of Korea, St. Vincent's Hospital
Korea (Republic of)
Sang-Yong Yoo, MD
GangNeung Asan Hospital
Korea (Republic of)
Chang-Hwan Yoon, MD
Seoul National University Bundang Hospital
Korea (Republic of)
Hyuck Jun Yoon, MD
Keimyung University Dongsan Medical Center
Korea (Republic of)
Junghan Yoon, MD
Yonsei University Wonju Severance Christian Hospital
Korea (Republic of)
Myeong-Ho Yoon, MD
Ajou University Hospital
Korea (Republic of)
Shin Eui Yoon, MD
Daejon Veteran Hospital
Korea (Republic of)
Young Won Yoon, MD
Gangnam Severance Hospital
Korea (Republic of)
Tae Jin Youn, MD
Seoul National University Bundang Hospital
Korea (Republic of)
Cheol Woong Yu, MD
Korea University Anam Hospital
Korea (Republic of)
Jeong Jin Yu, MD
Asan Medical Center
Korea (Republic of)
Tae Jin Yun, MD
Asan Medical Center
Korea (Republic of)
Review
TCTAP 2016 Gallery
TCTAP 2016 Daily
TCTAP Award 2016
- Master of the Masters
- Best Young Scientist Award
Slides
Program: Slide Presentations
Factoid
Video
Video On-Demand
Wrap-up Interviews
e-Science Station
Late Breaking Clinical Trial
2016 New Data from AMC
Abstracts
Cases
TCTAP Best Presenters
- Abstract
- Case
Faculty
International Faculty
- Invited Faculty
- Faculty of the Year
Korean Faculty
- Invited Faculty
- Faculty of the Year
Sponsorship
TCTAP 2016 Sponsor
Exhibition Booth Floor Plan
About TCTAP
Overview
Board Members
- Course Directors
- Course Co-Directors
- Scientific Committee
- Honorary Board
CVRF

Contact Us
FacebookYoutube
Visit Seoul