#### Service to the research community

- Editor
*Journal of the Korean Mathematical Society*. 2011-- Special issue on “the Seventh Workshop on Graph Classes, Optimization, and Width Parameters, Aussois, France (GROW2015)”, Discrete Applied Mathematics. 2016-2017. Call for Papers for GROW 2015.
- Special issue on “the Fifth Workshop on Graph Classes, Optimization, and Width Parameters, Daejeon, Korea, October 2011 (GROW2011)”,
*Discrete Applied Mathematics*. 2012-2013. - Special issue on “the Seventh Workshop on Graph Classes, Optimization, and Width Parameters, Aussois, France, October 2015 (GROW2015)”,
*Discrete Applied Mathematics*. 2016-2017.

- Program Committee
- 43rd International Workshop on Graph-Theoretic Concepts in Computer Science (WG2017), Heeze, the Netherlands, June 21-23, 2017.
- 27th International Symposium on Algorithms and Computation (ISAAC2016), Sydney, Australia, December 12-14, 2016.
- 21st European Symposium on Algorithms (ESA2013), Sophia Antipolis, France, September 2-4, 2013.
- 37th International Workshop on Graph-Theoretic Concepts in Computer Science (WG2011), Czech Republic, June 21-23, 2011.
- 7th Annual Conference on Theory and Applications of Models of Computation (TAMC 2010), Prague , Czech Republic, June 7-11, 2010.
- 35th International Workshop on Graph-Theoretic Concepts in Computer Science (WG2009), Montpellier, France, June 24-26, 2009.
- 2nd Canadian Discrete and Algorithmic Mathematics Conference (CanaDAM 2009), Montréal, Canada, May 25-28, 2009.

- Organizing Committee or Local Organizing Committee
- 2016 Combinatorics Workshop, KAIST, July 21-23, 2016.
- 1st Korean Workshop on Graph Theory, August 26-28, 2015 at KAIST.
- 27th International Conference on Formal Power Series and Algebraic Combinatorics (FPSAC2015), July 6-10, 2015 at KAIST.
- ICM2014 Satellite Conference on Extremal and Structural Graph Theory, Gyeongju, August 5-9, 2014.
- Member of ICM2014 Local Organizing Committee for ICM (International Congress of Mathematicians) 2014 at Seoul.
- 12th Annual Korea-Japan workshop on algebra and combinatorics, January 23-25, 2014, KAIST.
*5th workshop on Graph Classes, Optimization, and Width Parameters (GROW 2011)*, October 27-29, 2011, KAIST. This is a continuation of the series of meetings: Barcelona 2001, Prague 2005, Eugene 2007, and Bergen 2009.*Special session on graph theory*at Korean Mathematical Society Spring Meeting (with Seog-Jin Kim), April 2010.- I co-organized the
*Winter School on Algorithms and Combinatorics*, January 13-16, 2010 in Korea. - I co-organized the
*2009 Combinatorics Workshop*, August 20-21, 2009 at KAIST.

- Committee member of Mathematics for information sciences, Korean Mathematical Society, 2009.3.1.-2018.2.28.

#### Service to the society

- Organizing Korean Mathematical Olympiad (KMO, 한국수학올림피아드).
- I’ve been involved in selecting and educating highly gifted students in Korea to compete in International Mathematical Olympiad (IMO). For 2011-2012 and 2017-, I was/have been an executive member of the Board of Trustees (사업이사), Korean Mathematical Society (대한수학회) in charge of KMO.
- I’ve been to IMO2009 Bremen (Observer B), IMO2011 Amsterdam (Observer B), and IMO2012 Mar del Plata (Deputy Leader), IMO2016 Hong Kong (Observer B).
- I was also the deputy leader for the South Korean CGMO (China Girl’s Math Olympiad) team for 2012, held in Guangzhou, China.
- I was the deputy leader for the South Korean RMM (Romanian Master of Mathematics) team for 2017.
- Member of Korean Math Olympiad Committee, 2011-.

- Managing KAIST Math Problem of the Week. (2008-2012, 2014-)
- This is a weekly problem challenge for KAIST undergraduate students.

- Writing light articles.
- “2012년 아벨상 수상자의 업적 – 헝가리 출신 수학자 세머레디 교수”, The Newsletter of KMS, Korean Mathematical Society, vol. 148, pp. 7-9, March 2013.
- “2012년 국제수학올림피아드(IMO) 참가 보고”, The Newsletter of KMS, Korean Mathematical Society, vol. 145, pp. 13-22, Sep. 2012.
- “불규칙에서 규칙성 찾은’수학자, 아벨상 수상자로“, 사이언스 온, 한겨레신문(주), March 23, 2012.

(explaining the work of E. Szemerédi after he was announced as the Abel prize winner of 2012.) - Hot Math (따끈따끈한 수학), Math Donga, 2016. (Monthly articles on a mathematics magazine called the Math Donga 수학동아.)

- Several public lectures
- KAIST 명강 4기 대중강연, 2015년.

#### Service to the University

- KAIST 영재교육위원회 위원, 2015.4.9-2018.4.8.
- KAIST Press 편집기획위원회 위원, 2012.12.1-2016.11.30.
- KAIST 정보기술위원회 위원, 2011.5.1-2015.5.31.
- KAIST 정원 및 캠퍼스혁신 소위원회, 2014.3.1-2014.6.30.
- KAIST 홍보위원회, 2011.2.21-2013.2.20.