- 최수영 (아주대학교 수학과)
- Email : schoi [a] ajou.ac.kr
- Tel : +82-31-219-3322
- Fax : +82-31-219-3720
- Department of Mathematics, Ajou University, 206, World cup-ro, Yeongtong-gu, Suwon, 16499,
**Rep. of Korea**

- 13 March 1982, Daegu, Korea.

- Toric topology, Transformation group theory
- Combinatorial topology
- Algebraic combinatorics
- Topological Data Analysis

**Associate Vice President for Admissions**, Ajou University. (1 Aug 2022 -- 31 Jul 2024 (current))**Director**, Science Education Center for Gifted Student, Ajou University. (1 Mar 2019 -- 28 Feb 2023 (current))**Professor**, Department of Mathematics, Ajou University. (1 Mar 2020 -- )- Chair, Department of Mathematics, Ajou University. (1 Mar 2020 -- 28 Feb 2022)
- Associate Professor, Department of Mathematics, Ajou University. (1 Mar 2015 -- 28 Feb 2020)
- Assistant Professor, Department of Mathematics, Ajou University. (1 Mar 2011 -- 28 Feb 2015)
- JSPS Postdoctoral Research Fellow, Department of Mathematics, Osaka City University. (1 Sep 2009 -- 19 Feb 2011)
- BK21 Post Doctor in Department of Mathematical Sciences, KAIST. (1 Mar 2009 -- 31 Aug 2009)

**Associate Editor**, The Korean Journal of Mathematics (ISSN: 1976-8605) (1 Sep 2019 -- 31 Aug 2021)**Organizer**, Korean Mathematical Society (The 25th KMS Board Member) (1 Jan 2019 -- 31 Dec 2020)- Organizer, Korean Mathematical Society (The 24th KMS Board Member) (1 Jan 2017 -- 31 Dec 2018)
- Organizer, Korean Mathematical Society (The 23rd KMS Board Member) (1 Jan 2015 -- 31 Dec 2016)
**Member of subcommittee for topology**, Korean Mathematical Society (1 Mar 2018 -- 28 Feb 2021)- Member of subcommittee for topology, Korean Mathematical Society (1 Mar 2015 -- 28 Feb 2018)

- 3/2003 - 1/2009 : KAIST, Integrated M.S. & Ph.D. course, in Mathematics (Advisor: Prof. Dong Youp Suh)
- Thesis : Properties determined by Cohomology ring in Toric Topology
- 3/2000 - 2/2003 : KAIST, Bachelor
of Science in Mathematics (
*magna cum laude*) - 3/1998 - 2/2000 : Daegu Science High School
- 3/1995 - 2/1998 : Gyeongsin Middle School

- 30th Annual Excellent Paper Award, The Korean Federation of Science and Technology Societies(KOFST), 3 July 2020 (Scrap 1 )
- 2013 Sangsan Prize for young Mathematicians, The Korean Mathematical Society, 25 October 2013 (Scrap 1 2)
- TJ Park Science Fellowship (청암 과학 펠로 신진교수), POSCO TJ Park Foundation, 1 November 2012 (Scrap 1)
- JSPS Postdoctoral Research Fellowship, Japan Society for the Promotion of Science, 1 September 2009

- [39] Suyoung Choi, Mathieu Vallée,
*An algorithmic strategy for finding characteristic maps over wedged simplicial complexes*,**Pacific J. Math.**, to appear. arXiv:2111.07298 - [38] Suyoung Choi, Mathieu Vallée,
*Cohomological rigidity of the connected sum of three real projective spaces*,**Proc. Steklov Inst. Math.**, 317, to appear.

- [37] Li Cai, Suyoung Choi,
*Integral cohomology groups of real toric manifolds and small covers*,**Mosc. Math. J.**, 21 (3), 467--492

- [36] Li Cai, Suyoung Choi, Hanchul Park,
*On the KO-groups of toric manifolds*,**Algebr. Geom. Topol.**, 20 (2020) 2589--2607 - [35] Suyoung Choi, Hanchul Park,
*Multiplicative structure of the cohomology ring of real toric spaces*,**Homology Homotopy Appl.**, 22 (2020), no. 1, 139--157.

- [34] Suyoung Choi, Shizuo Kaji, Hanchul Park,
*The cohomology groups of real toric varieties associated to Weyl chambers of type C and D*,**Proc. Edinb. Math. Soc.**, 62 (2019), 861--874. - [33] Soojin Cho, Suyoung Choi, Shizuo Kaji,
*Geometric representations of finite groups on real toric spaces*,**J. Korean Math. Soc.**, 56 (2019), no. 5, 1265--1283. (This paper was selected as the best Korean mathematical paper by KOFST in 2019.)
- [32] Suyoung Choi, Hanchul Park,
*Small covers over wedges of polygons*,**J. Math. Soc. Japan**, 71 (2019), no. 3, 739--764. - [31] Suyoung Choi, Kyoungsuk Park,
*Example of C-rigid polytopes which are not B-rigid*,**Math. Slovaca**, 69 (2019), no. 2, 437--448.

- [30] Suyoung Choi, Seonjeong Park,
*Strong cohomological rigidity of toric varieties*,**Proc. Roy. Soc. Edinburgh Sect. A.**147 (2017), no. 5, 971--992. - [29] Suyoung Choi, Boram Park, Hanchul Park,
*The Betti numbers of real toric varieties associated to Weyl chambers of type B*,**Chinese Ann. Math. Ser. B.**38 (2017), no. 6, 1213--1222. - [28] Suyoung Choi, Hanchul Park,
*Wedge operations and torus symmetries II*,**Canad. J. Math.**69 (2017), no. 4, 767--789. - [27] Suyoung Choi, Hanchul Park,
*On the cohomology and their torsion of real toric objects*,**Forum Math.**29 (2017), no. 3, 543--553. - [26] Suyoung Choi, Hanchul Park,
*Wedge operations and a new family of projective toric manifolds*,**Israel J. Math.**219(1) (2017), 353--377. - [25] Suyoung Choi, Boram Park, Seonjeong Park,
*Pseudograph and its associated real toric manifold*,**J. Math. Soc. Japan**, 69(2) (2017), 693--714. - [24] Suyoung Choi, Mikiya Masuda, Sang-il Oum,
*Classification of real Bott manifolds and acyclic digraphs***Trans. Amer. Math. Soc.**369 (2017), 2987--3011. - [23] Suyoung Choi, Shizuo Kaji, Stephen Theriault,
*Homotopy decomposition of a suspended real toric space*,**Bol. Soc. Mat. Mex.**(3) 23 (2017), no. 1, 153--161. (the memorial volume for Professor Gitler)

- [22] Suyoung Choi, Seonjeong Park,
*Projective bundles over smooth compact toric surfaces*,**Internat. J. Math.**27 (4) (2016), 1650032, 30 pp. - [21] Suyoung Choi, Hanchul Park,
*Wedge operations and torus symmetries*,**Tohoku Math. J.**(2), 68(1) (2016), 91--138.

- [20] Suyoung Choi,
*Classification of Bott manifolds up to dimension 8*,**Proc. Edinb. Math. Soc.**(2), 58(3) (2015), 653--659. - [19] Suyoung Choi, Mikiya Masuda, Satoshi Murai,
*Invariance of Pontrjagin classes for Bott manifolds*,**Algebr. Geom. Topol.**, 15(2) (2015), 965--986. - [18] Suyoung Choi, Hanchul Park,
*A new graph invariant arises in toric topology*,**J. Math. Soc. Japan**, 67(2) (2015), 699-720.

- [17] Suyoung Choi,
*Different moment-angle manifolds arising from two polytopes having the same bigraded Betti numbers*,**Algebr. Geom. Topol.**, 13(6) (2013), 3639--3649.

- [16] Suyoung Choi, Mikiya Masuda,
*Classification of Q-trivial Bott manifolds*,**J. Symplectic Geom.**10(3) (2012), 447--462. - [15] Suyoung Choi, Dong Youp Suh,
*Strong cohomological rigidity of a product of projective spaces*,**Bull. Korean Math. Soc.**49(4) (2012), 761--765. - [14] Suyoung Choi, Seonjeong Park, Dong Youp Suh,
*Topological classification of quasitoric manifolds with second Betti number 2*,**Pacific J. Math.**256(1) (2012), 19--49.

- [13] Suyoung Choi, Mikiya Masuda, Dong Youp Suh,
*Rigidity problems in toric topology, a survey*,**Proc. Steklov Inst. Math.**, 275 (2011), 177--190. - [12] Suyoung Choi, Shintaro Kuroki,
*Topological classification of torus manifolds which have codimension one extended actions*,**Algebr. Geom. Topol.**11(5) (2011), 2655--2679. - [11]* Suyoung Choi,
*On Petrie's theorem for torus manifolds*, RIMS Kokyuroku, 1732 (2011), 95--100. - [10] Suyoung Choi, Jang Soo Kim,
*Combinatorial rigidity of 3-dimensional simplicial polytopes*,**Int. Math. Res. Not. IMRN.**2011(8), (2011), 1935--1951. - [9] Suyoung Choi, Dong Youp Suh,
*Properties of Bott manifolds and cohomological rigidity*,**Algebr. Geom. Topol.**11(2), (2011), 1053--1076.

- [8] Suyoung Choi, Taras E. Panov, Dong Youp Suh,
*Toric cohomological rigidity of simple polytopes*,**J. London Math. Soc.**82(2), (2010), 343--360. - [7] Suyoung Choi,
*The number of orientable small covers over cubes*,**Proc. Japan Acad.**, 86, Ser. A. (2010), no.6, 97--100. - [6] Suyoung Choi, Jang Soo Kim,
*A combinatorial proof of a formula for Betti numbers of a stacked polytope*,**Electron. J. Combin.**17(1) (2010), #R9. - [5] Suyoung Choi, Mikiya Masuda, Dong Youp Suh,
*Topological classification of generalized Bott towers*,**Trans. Amer. Math. Soc.**362 (2010), 1097--1112. - [4] Suyoung Choi, Mikiya Masuda, Dong Youp Suh,
*Quasitoric manifolds over a product of simplices*,**Osaka J. Math.**47 (2010), 109--129.

- [3]* Suyoung Choi,
*Counting on real Bott manifolds*, RIMS Kokyuroku, 1690 (2009), 69--71.

- [2] Suyoung Choi,
*The number of small covers over cubes*,**Algebr. Geom. Topol.**8(4) (2008), 2391--2399. - [1]* Suyoung Choi,
*Small covers over cubes*, Trend in Math. 10 (2008), no. 1, 81--83.

- [1] Suyoung Choi, Taekgyu Hwang,
*Gromov width of symplectic toric manifolds associated with graphs*, arXiv:2011.09729 .

- [3] Ho Kyoung Ko, Suyoung Choi, Shizuo Kaji,
*Who Has Given up on Mathematics? A data analysis*, Asia Pacific Education Review (2021) 22:699--714 - [2] Suyoung Choi, Ahyun Goo, Ho Kyoung Ko,
*The Case of Polymath Activities Using Collective Intelligence*, East Asian Mathematical journal, 37 (2021), No. 4, 523--541 - [1] Ho Kyoung Ko, Hyung Won Kim, Shizuo Kaji, Suyoung Choi,
*Elementary school students who give up on learning mathematics: Correlations with non-cognitive learner characteristics*, J. Korea Soc. Math. Ed. Ser. C, 20 (2017), No. 2, 143--151.

- [4] 오일러의 보석 (Translation of Euler's gem written by David Richeson), ISBN 9791125102595, Kyowoo, 2018.
- [3] 드론, 수학으로 날다!, ISBN 9791125101994, Kyowoo, 2017.
- [2] 수학1, 수학2, 수학3 (Government-authorized Textbooks for middle school students), Kyohak, 2015개정 교육과정, 2017.
- [1] 수학1, 수학2, 수학3 (Government-approved Textbooks for middle school students), Kyohak, 2009개정 교육과정, 2013.

- [1] 위상 데이터 분석(TDA) 기법을 이용한 차량의 추돌 가능성 예측 방법 및 장치(Crash probability prediction method and apparatus for vehicle using TDA technique), Korea Patent 10-2020-0025618, filed in 28 Feb 2020, patent pending

- 3/2019 - 2/2024 : Basic Science Research Program (중견연구자 지원사업), the national Research Foundation of Korea(NRF), about 160,000 USD per year
- Research Title : Establishment of real toric topology and classification of real toric manifolds
- 11/2016 - 10/2019 : Basic Science Research Program (일반연구자 지원사업(기본-후속)), the national Research Foundation of Korea(NRF), about 50,000 USD per year
- Research Title : Classification of topological spaces admitting torus actions
- 1/2013 - 12/2014 : TJ Park Science Fellowship (청암 과학 펠로), POSCO TJ Park Foundation, about 35,000 USD per year
- Research Title : Classification of toric manifolds
- 9/2012 - 8/2014 : Basic Science Research Program (일반연구자 지원사업(모험)), the national Research Foundation of Korea(NRF), about 50,000 USD per year
- Research Title : Classification of aspherical manifolds and real toric manifolds
- 9/2011 - 8/2016 : Basic Science Research Program (일반연구자 지원사업(기본)), the national Research Foundation of Korea(NRF), about 35,000 USD per year
- Research Title : Classification of topological spaces admitting torus actions
- 9/2009 - 2/2011 : JSPS Postdoctoral Research Fellowship, Japan Society for the Promotion of Science, September 1, 2009
- Research Title : Toric Topology and Combinatorics

- 4/2021 - 12/2022 : 국토교통기술사업화지원사업, 국토교통부
- Joint work with (주)HBC
- 10/2018 - 12/2019 : R&D Project (창업성장기술개발사업), Ministry of SMEs and Startups, about 50,000 USD
- Joint work with (주)HBC
- Research Title : Detection of buried objects using Deep learning
- 7/2017 - 7/2018 : R&D Project, (주)HBC, about 50,000 USD
- Research Title : Research on theory of prediction technology for the information of steel tower foundation using electrical resistivity exploration
- 12/2016 - 8/2017 : R&D Project, (주)GK Engineering, about 10,000 USD
- Research Title : Research on sinkhole exploration by image and big-data analysis

- 4/2021 - 7/2021 : 과학기술인력양성 사업, 과학기술정보통신부
- Research Title : 수학인재양성 연구센터 운영방안 기획 연구
- 11/2019 - 5/2020 : 2019 과학영재교육정책기획연구 사업, 과학기술정보통신부
- Research Title : A preliminary study on the STEM education systmem for leading 4th Industrial revolution

- 10/2019 - 3/2022 : 산업전문인력양성사업 (P.I.: Prof. Bong Sup Song (Ajou Univ.)), 한국산업기술진흥원
- Research Title : 미래형자동차 R&D 전문인력양성사업
- 8/2013 - 12/2013 : R&D Project, (주)Daekyo, P.I.: Prof. Ho Kyoung Ko (Ajou Univ.)
- Research Title : Smart learning on Mathematics

- The 6th Korea Toric Topology Workshop, KAIST, Daejeon,
**Korea**, July 11--13, 2022 - Title : Industrial math in civil engineering
- 2022 KMS Spring Meeting, Online, Korean Mathematical Society,
**Korea**, April 28--29, 2022 - Title : Toric colorizable PL spheres with a few vertices
- Toric Topology 2022 in Osaka, Online, OCAMI (Osaka City University), Osaka,
**Japan**, March 23--25, 2022 - Title : Cohomological rigidity for Bott manifolds

- Colloquium talk at Ulsan University, Ulsan Univ., Ulsan,
**Korea**, November 11, 2021 - Title : 위상적데이터분석(TDA)의 산업수학에서의 활용
- Topology of torus actions and related topics, Online, Sirius Mathematics Center, Sochi,
**Russia**, October 25--29, 2021 - Title : Puzzle algorithm for finding mod $2$ characteristic maps over wedged simplicial complexes
- International polyhedral product seminar, Online, Princeton Univ.,
**USA**, October 21, 2021 - Title : On the classification of real toric manifolds

- The 8th East Asian Conference on Algebraic Topology(EACAT), VIASM and VNI, Hanoi,
**Vietnam**, December 14--18, 2020 - (Plenary talk) Title : TBA
- Topology and geometry of group actions, Online conference,
**Russia**, November 18-22, 2020 - Title : Gromov width of symplectic toric manifolds associated with graph associahedra
- 2020 KMS Annual Meeting, Virtual conference,
**Korea**, October 23-24, 2020 - Title : real toric manifold, and its cohomology
- Workshop on Polyhedral Products in Homotopy Theory, The Fields Institute, Toronto,
**Canada**, January 20--24, 2020 - Title : Topology of real moment-angle complexes and real toric spaces

- Toric Topology 2019 in Okayama, Okayama University of Science, Okayama,
**Japan**, November 18 -- 21, 2019 - Title : On the classification of (real) toric manifolds of Picard number 4
- The 3rd Pan Pacific International Conference on Topology and Applications (PPICTA), Xiangyu Hotel, Chengdu,
**China**, November 8--13, 2019 - Title : Topology of real toric manifolds and its application
- 2019 International conference of The Kangwon-Kyungki Mathematical Society, Daegu Gyeongbuk Design Center, Daegu,
**Korea**, June 28 -- 30, 2019 - Title : Small cover and cohomological rigidity problem
- Mini workshop on toric topology and related topics, Korea Chamber of Commerce and Industry, Seoul,
**Korea**, May 27, 2019 - Title : On the real toric spaces
- The 6th International Electric Vehicle Expo, private session organized by Ajou Univ., ICC Jeju, Jeju,
**Korea**, May 7 -- 11, 2019 - Title : Topological Data Analysis on Object Detection

- Ajou Data Science Forum - Data Science in Finance, Ajou University, Suwon,
**Korea**, December 14, 2018 - Title : Topological Data Analysis on Image classification
- 2018 Joint Meeting of the Korean Mathematical Society and the German Mathematical Society, COEX, Seoul,
**Korea**, October 3--6, 2018 - Title : Torsions in the cohomology of real toric manifold
- 88th KPPY Combinatorics Workshop, Yeungnam Univ., Daegu,
**Korea**, August 31, 2018 - Title : Betti numbers of real toric varieties associated to Weyl chambers
- Invited talk, IBS-CGP, Pohang,
**Korea**, August 30, 2018 - Title : On the topology of real toric manifolds
- Invited talk, Ryukyu Univ., Nakagami-gun, Okinawa,
**Japan**, July 30, 2018 - Title : topology of real toric spaces
- 20th KIAS Combinatorics Workshop, Duksung Women's Univ., Seoul,
**Korea**, June 1--2, 2018 - Weyl group action on real toric manifolds and its geometric representations
- Algebraic Topology, Combinatorics, and Mathematical Physics, Steklov Mathematical Institute, Moscow,
**Russia**, May 24--30, 2018 - Title : Cohomology formulae of real toric spaces
- 2018 KMS Spring Meeting, Kyung Hee Univ., Seoul,
**Korea**, April 20--22, 2018 - Title 1 : Cohomology of real toric spaces
- Title 2 : Industrial math on civil engineering
- Colloquium talk at Ajou University, Ajou Univ., Suwon,
**Korea**, April 13, 2018 - Title : The cohomology rings of real toric spaces
- Special Lectures at Sungkyunkwan University, Sungkyunkwan Univ., Suwon,
**Korea**, April 13, 2018 - Title : Topology of real toric varieties
- Invited talk at Osaka City University, Osaka City Univ., Osaka,
**Japan**, February 26, 2018 - Title : Cohomology of real toric spaces

- Algebraic Topology Seminar, Princeton Univ., Princeton, NJ,
**USA**, November 30, 2017 - Title : Multiplicative structure of the cohomology of real toric spaces
- Invited talk, Western Univ., London, ON,
**Canada**, November 22, 2017 - Title : Introduction to real toric spaces
- Encounter in Topology 'n Algebra,
Scuola Superiore di Catania, Catania,
**Italy**, May 31 -- June 4, 2017 - Title : Finite group action on real toric variety and its geometric representations
- Colloquium talk at UTRGV, The Univ. of Texas Rio Grande Valley, Edinburg, Texas,
**USA**, April 27, 2017 - Title : Topology and combinatorics of real toric manifolds

- 79th KPPY Combinatorics Workshop, Kyungpook National Univ., Daegu,
**Korea**, October 8, 2016 - Title : Acyclic digraphs and real Bott manifolds
- Invited seminar, Osaka City University, Osaka,
**Japan**, July 27, 2016 - Title : Geometric representation of Weyl groups on the corresponding real toric manifolds
- Colloquium talk at KAIST, KAIST, Daejeon,
**Korea**, March 10, 2016 - Title : Topology of real toric spaces
- Invited series seminar, Fudan University, Shanghai,
**China**, January 6--7, 2016 - Title : Topology and Combinatorics of real toric spaces

- The 6th East Asian Conference on Algebraic Topology(EACAT), NIMS, Daejeon,
**Korea**, November 30 -- December 4, 2015 - Title : Homology of real toric varieties associated to Weyl groups
- International Open Chinese-Russian Conference -- Torus Actions: Topology, Geometry and Number Theory, Chinese Academy of Sciences, Beijing,
**China**, October 26--29, 2015 - Title : The Betti numbers of real toric varieties associated to Weyl groups of regular types
- Invited series seminar, KAIST, Daejeon,
**Korea**, October 7, 14, 21, 2015 - Title : Topology and Combinatorics of real toric spaces
- Combinatorial Constructions in Topology, Univ. of Regina, Regina, SK,
**Canada**, August 17--21, 2015 - Title : A new family of projective toric manifolds
- 2015 KMS Spring Meeting, Pusan National Univ., Pusan,
**Korea**, April 24--26, 2014 - Title : On the topology of real toric spaces
- Geometry and Topology, Princeton Univ., Princeton, NJ,
**USA**, March 18--21, 2015 - Title : Construction of a small cover with odd torsion
- 7th KIAS Combinatorics Workshop, KIAS, Seoul,
**Korea**, March 13--14, 2015 - Title : Small cover and puzzle
- Perspectives in Lie Theory - session : Algebraic topology, geometric and combinatorial group theory, Centro di Ricerca Matematica - Ennio De Giorgi, Pisa,
**Italy**, February 8--28, 2015 - Title : Cohomology of small cover and its torsion
- Topology Seminar, Univ. of Southampton, Southampton,
**UK**, February 2, 2015 - Title : The cohomology and their torsion of real toric manifolds

- 2014 KAIST CMC Discrete Math Workshop, KAIST, Daejeon,
**Korea**, December 10--12, 2014 - Title : The Betti numbers of real toric varieties corresponding to generalized graph associahedra
- Brown Bag Lectures at Ajou University, Ajou Univ., Suwon,
**Korea**, September 16, 2014 - Colloquium talk at Sogang University, Sogang Univ., Suwon,
**Korea**, September 11, 2014 - Title : Classification of toric varieties
- Seoul ICM 2014, COEX, Seoul,
**Korea**, August 13--21, 2014 - Title 1 (Topology) : Topology of generalized Bott manifolds
- Title 2 (Combinatorics): Graph invariants arising from toric topology
- ICM 2014 Satellite conference : Topology of torus actions and applications to geometry and combinatorics, Daejeon Convention Center, Daejeon,
**Korea**, August 7--11, 2014 - Title : On the classification of toric varieties
- 64th KPPY Combinatorics Workshop, Kyungpook National Univ., Daegu,
**Korea**, June 20, 2014 - Title : The a-number of graphs and the topology of small covers
- Invited Seminar, NIMS, Daejeon,
**Korea**, June 3, 2014 - Title : Topology of small covers
- 2014 KMS Spring Meeting, Gangneung-Wonju National Univ., Gangneung,
**Korea**, April 24--26, 2014 - Title : Cohomological rigidity problem for toric manifolds
- The 12th Korea-Japan Workshop on Algebra and Combinatorics, KAIST, Daejeon,
**Korea**, January 23--25, 2014 - Title : Enumeration of toric objects and wedge operation on simplicial complexes.

- The 5th East Asian Conference on Algebraic Topology (EACAT), Chinese Academy of Sciences, Beijing,
**China**, December 2--6, 2013 - Title : On the cohomology of real toric manifolds
- KAIST Discrete Math Seminar, KAIST, Daejeon,
**Korea**, November 18, 2013 - Title : The rational Betti number of small covers and its combinatorics
- International Open Chinese-Russian conference "Torus Actions: Topology, Geometry and Number Theory", Pacific National Univ., Khabarovsk,
**Russia**, September 2--7, 2013 - Title : Classification of torus manifolds and wedge operations
- Algebraic Combinatorics Seminar, KIAS, Seoul,
**Korea**, August 26, 2013 - Title : The number of real toric varieties
- 58th KPPY Combinatorics Workshop, Yeungnam Univ., Daegu,
**Korea**, August 21, 2013 - Title : Combinatorial description of Betti numbers of toric varieties
- 2013 Combinatorics Workshop, NIMS, Daejeon,
**Korea**, August 7--9, 2013 - Title : Introduction to the a-number of graphs and hypergraphs
- The Asian Mathematical Conference (AMC) 2013 , BEXCO, Busan,
**Korea**, June 30 -- July 4, 2013. - Title : Wedge operations and torus symmetries
- Joint International Meeting of the AMS and the Romanian Mathematical Society, Univ. of Alba Iulia, Alba Iulia,
**Romania**, June 27 -- 30, 2013. - Title : Wedge operations and torus symmetries
- Algebraic Topology Seminar, Princeton Univ., Princeton, NJ,
**USA**, February 21, 2013 - Title : Wedge operations and torus symmetries
- University of Minnesota Combinatorics Seminar, Univ. of Minnesota, Minneapolis, Minnesota,
**USA**, February 15, 2013 - Title : A new graph invariant arises in toric topology : rational Betti numbers of real toric varieties arising from graphs
- Invited Seminar, Osaka City Univ., Osaka,
**Japan**, January 23, 2013 - Title : Wedge operation and symmetry of manifolds

- 건국-아주-인하 수학과 연합세미나, Konkuk Univ., Seoul,
**Korea**, December 17, 2012 - Title : Rational Betti number of generalized real Hassenberg varieties and new graph invariants
- Toric Topology 2012 in Osaka, Osaka City Univ., Osaka,
**Japan**, November 16--19, 2012 - Title : On the toric rigidity of simple polytopes
- Colloquium talk at Sungkyunkwan University, Sungkyunkwan Univ., Suwon,
**Korea**, October 18, 2012 - Title : Topology of real Bott manifolds
- 2012 Combinatorial workshop, Chonnam National Univ., Gwangju,
**Korea**, August 9, 2012 - Title : Polytopes and combinatorics in toric topology
- 조선대학교 수학교육과 특강, Chosun Univ., Gwangju,
**Korea**, June 21, 2012 - Title : Catalan numbers and associahedra
- 2012 The KMS Spring Meeting, Sookmyung Women's Univ., Seoul,
**Korea**, April 28, 2012 - Title : Different moment-angle manifolds arising from two polytopes having the same bigraded Betti numbers
- Princeton-Rider Workshop on Homotopy Theory and Toric Spaces (sponsored by Algebraic Topology Seminar), Rider Univ., Lawrenceville, NJ,
**USA**, February 23--25, 2012 - Title : Toric rigidity of simple polytopes and moment-angle manifolds
- Algebraic topology seminar at Princeton University, Princeton Univ., Princeton, NJ,
**USA**, February 16, 2012 - Title : Cohomological rigidity problems in Toric topology

- 건국-아주-인하 수학과 연합세미나, Inha Univ., Incheon,
**Korea**, December 9, 2011 - Title : Classification problems in toric topology
- Toric Topology 2011 in Osaka, Osaka City Univ., Osaka,
**Japan**, November 28--30, 2011 - Title : Invariance of Pontrjagin classes of torus manifolds
- International Conference "Toric Topology and Automorphic Functions", Pacific National Univ., Khabarovsk,
**Russia**, September 5--10, 2011 - Title : Classification of Bott manifolds, and cohomological rigidity problems
- Workshop of Department of Mathematical Sciences, KAIST, Lotte Resort, Buyeo,
**Korea**, July 26--27, 2011 - Title : Topology of toric manifolds
- Conference: Toric Methods in Homotopy Theory and Related Subjects, Queens Univ., Belfast,
**UK**, July 18-20, 2011 - Title : Invariance of Pontrjagin classes of generalized Bott manifolds
- Invited Seminar: Program of Low dimensional topology seminar, Max Planck Institute for Mathematics, Bonn,
**Germany**, July 11, 2011 - Title : Topological Classification of Bott manifolds
- Colloquium talk at Ajou University, Ajou Univ., Suwon,
**Korea**, June 10, 2011 - Title : Introduction to toric topology and cohomological rigidity problems
- Invited Seminar, Topology regular seminar, Seoul National Univ., Seoul,
**Korea**, May 17, 2011 - Title : Classification of Bott manifolds
- 2011 The Korean Mathematical Society Spring Meeting, Korea Univ., Seoul,
**Korea**, April 30, 2011 - Title : On Petrie's conjecture for torus manifolds
- Workshop celebrating the retirement of Professor Kitada, Kyoto,
**Japan**, January 12, 2011 - Title : On Petrie's conjecture for torus manifolds

- Invited Seminar, Ajou Univ., Suwon,
**Korea**, December 10, 2010 - Title : Topology of torus manifolds
- The 37th Symposium of Transformation Groups, Kyushu Univ., Kyushu,
**Japan**, November 23 - 24, 2010 - Title : Cohomological rigidity of polytopes in toric topology
- Colloquium talk at Osaka City University, Osaka City Univ., Osaka,
**Japan**, November 17, 2010 - Title : Toric topology and polytope theory
- Topological methods in toric geometry, symplectic geometry and combinatorics, BIRS, Banff, AB,
**Canada**, November 7 - 17, 2010 - Title : Torus actions on cohomology generalized Bott manifolds
- The Homotopy Theory Symposium 2010, Kyushu Univ., Kyushu,
**Japan**, October 31 - November 3, 2010 - Title : Torus actions on cohomology Bott manifolds
- Workshop on Geometry & Topology 2010, Univ. of Fribourg, Fribourg,
**Switzerland**, September 16-18, 2010 - Title : Real Bott manifolds and acyclic digraphs
- Group Actions in Topology and Analysis - 4th GAF Conference, Univ. of Milano-Bicocca, Milan,
**Italy**, September 13 - 17, 2010 - Title : Invariance of Pontrjagin classes of Bott manifolds
- RIMS conference 2010 Transformation Groups and Surgery Theory , RIMS, Kyoto,
**Japan**, August 30 - September 3, 2010 - Title : Invariance of Pontrjagin classes of Bott manifolds
- The International Conference
"GEOMETRY, TOPOLOGY, ALGEBRA and NUMBER THEORY, APPLICATIONS"
, Steklov Mathematical Institute, Moscow,
**Russia**, August 16 - 20, 2010 - Title : Real Bott manifolds and acyclic digraphs
- The 3rd Topology Workshop, KAIST, Daejeon,
**Korea**, August 3-4, 2010 (Poster)
- Title : Real Bott manifolds and acyclic digraphs
- International Conference on Algebraic and Geometric topology, Capital Normal Univ., Beijing,
**China**, June 28- July 2, 2010 - Title : Invariance of Pontrjagin classes of Bott manifolds
- Workshop on Toric Topology and Related Topics, Fudan Univ., Shanghai,
**China**, May. 2-5, 2010 - Title : The classification of four-stage Bott manifolds
- Invited Seminar, Okayama Univ., Okayama,
**Japan**, April 13, 2010 - Title : Cohomological rigidity problem and Q-trivial Bott manifold
- Toric Topology 2010 in Himeji, Egret-Himeji, Himeji,
**Japan**, April 10-11, 2010 - Title : Homology group of moment angle complex of certain polytopes
- Ikuta Seminar on Toric Topology, Meiji Univ., Tokyo,
**Japan**, March 6-7, 2010 - Title : Invariant of real Bott manifolds
- KAIST Toric Topology Workshop 2010, KAIST, Daejeon,
**Korea**, February 22-26, 2010 - Title : Combinatorial rigidity of 3-dimensional simplicial polytopes
- 37th KPP Combinatorics Workshop, Kyungpook National Univ., Daegu,
**Korea**, January 16, 2010 - Title : Cohomological rigidity of reducible simplicial polytopes

- The 3rd East Asia Conference on Algebraic Topology, Vietnam National Univ., Hanoi,
**Vietnam**, Dec. 14-18, 2009 - Title : Classification of Q-trivial Bott manifolds
- Toric Topology Seminar in Osaka, 2009, Osaka City University, Osaka,
**Japan**, Dec. 7-9, 2009 - Title : Classification of Q-trivial Bott manifolds
- Bratislava Topology Symposium "Group Actions and Homogeneous Spaces", Comenius University, Bratislava,
**Slovakia**, Sep. 7-11, 2009 - Title : Real Bott manifolds and acyclic digraphs
- Transformation groups from a new viewpoint, RIMS, Kyoto,
**Japan**, Aug. 17-20, 2009 - Title : The number of small covers over cubes
- The Korean Mathematical Society 09 Spring Symposium,
Ajou University, Suwon,
**Korea**, 25. April, 2009 - Title : Tor-algebra and Cohomological Rigidity of Simple Polytopes with Few Facets
- Korea-Japan Workshop on Algebra and Combinatorics, Pusan National Univ., Pusan,
**Korea**, Feb. 9-10, 2009 - Title : Tor-algebra and Cohomological rigidity of simple polytopes with few facets
- KAIST combinatorics Seminar, KAIST, Daejon,
**Korea**, Feb. 4-5, 2009 - Title : Cohomological rigidity of simple polytopes with few facets
- 2009 ASARC Workshop at Daecheon, Daecheon,
**Korea**, Jan. 29-31, 2009 - Title : On the topological classification of toric manifolds

- The 2nd East Asia Conference on Algebraic Topology, National Univ. of Singapore, Singapore,
**Singapore**, Dec. 15-19, 2008 - Title : Properties of Bott towers in Toric Topology
- The 28th PNU-POSTECH Algebraic Combinatorics Seminar, Pusan National Univ., Pusan,
**Korea**, 15th November 2008 - Title : Combinatorics on bigraded Betti numbers of simple polytopes
- 2008 Global KMS International Conference, Jeju Internationl Convention Center, Jeju,
**Korea**, 23th-25th October 2008 - Title : Toric cohomological rigidity of simple polytopes (Presentation)
- 2008 ASARC-Conference on transformation group theory, KAIST, Daejon,
**Korea**, 29th August 2008 - Title : Properties of Bott tower (Presentation)
- 2008 Workshop on Combinatorics,Sungkyunkwan Univ, Suwon,
**Korea**, 7th-8th August 2008 - Title : Cohomological Rigidity of simple polytopes (Presentation)
- New Horizons in Toric Topology,University of Manchester, Manchester,
**UK**, 7th-11th July 2008 - Title : The number of small covers over cubes (Poster)
*A prizewinning work* - Title : Toric cohomological rigidity of simple polytopes (Poster)
- The Korean Mathematical Society 08 Spring Symposium,
Keimyoung University, Daegu,
**Korea**, 26. April, 2008 - Title : The number of small covers over cubes (Presentation)

- Osaka
City University Summer School on symplectic Geometry and toric topology,
Osaka City University, Osaka,
**Japan**, 17th-27th. July, 2007 - Title : The cohomology ring and Bott tower structure

- Co-organize The 6th Korea Toric Topology Workshop, Daejeon,
**Korea**, July 11--13, 2022 - Co-organize Workshop on Artificial Intelligence for Industrrial Mathematics, The Suites hotel Jeju, Jeju,
**Korea**, June 18--21, 2022 - Co-organize a special session (toric topology), 2021 KMS Annual Meeting, online,
**Korea**, October 20--22, 2021 - Co-organize 2019 International Joint Conference on AI & Data Science: Mathematics and Applications, Suwon Convention Center, Suwon,
**Korea**, November 4--5, 2019 - Co-organize Ajou-Kyushu joint workshop on Industrial Mathematics, IMI Auditorum, Kyushu University, Fukuoka,
**Japan**, December 21--22, 2018 - Co-organize Optimization and Learning Tutorial 2018, Ajou University, Suwon,
**Korea**, March 24--31, 2018 - Co-organize The 4th Korea Toric Topology Winter Workshop, Jeju,
**Korea**, December 26--29, 2016 - Co-organize The 3rd Korea Toric Topology Winter Workshop, Gyeongju,
**Korea**, December 28--30, 2015 - Local organizer of The 6th East Asian Conference on Algebraic Topology (EACAT), Daejeon,
**Korea**, December 1--4, 2015 - Co-organize The 2nd Korea Toric Topology Winter Workshop, Jeju,
**Korea**, December 26--28, 2014 - Local organizer of 2014 Combinatorics workshop, Suwon,
**Korea**, October 31--November 11, 2014 - Local organizer of ICM 2014 satellite conference : Topology of torus actions and applications to geometry and combinatorics
- Co-organize 2013 Korea Toric Topology Winter Workshop
- Organize a regular workshop on topology and combinatorics at Ajou University: Topology and Combinatorics Seminar since 2011~
current - Co-organize Toric Topology Seminar in Osaka, 2009

- Leader of the Korea Mathematical Olympiad team at The Cyberspace Mathematical Competition (CMC), July 12--14, 2020
- Deputy Leader of the Korea Mathematical Olympiad team at the 60th International Mathematical Olympiad (IMO), Bath,
**UK**, July 10--22, 2019 - Deputy Leader of the Korea Mathematical Olympiad team at the 59th International Mathematical Olympiad (IMO), Cluj-Napoca,
**Romania**, July 03--14, 2018 - Deputy Leader of the Korea Mathematical Olympiad team at the 58th International Mathematical Olympiad (IMO), Rio de Janjeiroi,
**Brazil**, July 12--23, 2017 (Scrap 1) - Deputy Leader of the Korea Mathematical Olympiad team at the 8th Romanian Master of Mathematics (RMM), Bucharest,
**Romania**, February 24--29, 2016 - Deputy Leader of the Korea Mathematical Olympiad team at the 56th International Mathematical Olympiad (IMO), Chiang Mai,
**Thailand**, July 4--16, 2015 (Scrap 1)

- Interview at the main news at KBS : 30 Aug 2019, 아이즈원 탄생한 '프듀48'도 조작 의심 정황 포착
- Interview at the main news at SBS : 17 Aug 2014, 빅데이터 시대…'수학 전공'이 우대받는다
- Expert's consultation for the entertainment show, entitled 문제적남자, of tvN since January 2018 until July 2019
- Expert's consultation for POLYMATH project of a highschool-level math journal (수학동아) since May 2017

- Jiyeon Moon (Ph.D. March 2016 -- August 2021)
- Miyen Kang (Integrated M.S. & Ph.D. course March 2020 -- current) - Industrial Math track
- Sung Hyun Yoo (Master course. March 2020 -- current)
- Jiyoon Lee (Master course. September 2021 -- August 2022) - Industrial Math track
- Hankyoung Lee (Master course. March 2019 -- current) - Industrial Math track
- Hyuntae Jang (Master course. September 2018 -- August 2020) (P.h.D. course. September 2020 -- current)
- Taegon Kim (Master course. March 2017 -- February 2019) - Industrial Math track
- Sanggun Park (Master course. March 2012 -- February 2014)

- Xin Fu (September 2020 -- current)
- Taekkyu Hwang (September 2019 -- current)
- Dong Gyu Lee (April 2019 -- July 2019)
- Seonjeong Park (June 2018 -- August 2019), Assistent Professor, Jeonju University
- Hyowon Park (March 2014 -- August 2014)
- Hanchul Park (March 2012 -- September 2013), Assistent Professor, Jeju National University

- 위상수학 (Topology) (MATH341)
- 응용산업수학세미나 (Seminar in Applied and Industrial Mathematics) (MATH7612) (co-teaching with Prof. Dongwook Shin)

- 응용산업수학특강 (Topics in Applied Mathematics) (MATH7611)
- 산업수학프로젝트2 캡스톤디자인 (Industrial Mathematics Project 2) (MATH404)
- 위상수학 (Topology) (10156)
- 융합인재및영재교육실습 (Practicum in Converegence and Gifted Education) (EDU5197)
- 아주희망 (CAJO114)
- 수학Lab1 (Mathematics LAB1) (MATH104)

- Differentail Geometry II (MATH639)
- 데이터과학과 교육문제해결 (Data Science and problem solving for education) (EDU571)
- 산업수학프로젝트1 캡스톤디자인 (Industrial Mathematics Project 1) (MATH304)
- 수학교육연습(10474)
- 교육행정연습(8292)
- 수학Lab2 (Mathematics LAB2) (MATH105)

- Differentail Geometry I (MATH638)
- 수학논리및논술 (Mathematical Logic and Essay) (50171)
- 아주희망 (CAJO114)
- 수학Lab1 (Mathematics LAB1) (MATH104)

- Topology (MATH341)
- Topics in Geometry (MATH735)

- Elementary Discrete Modeling (MATH305)
- Topics in Applied and Industrial Mathematics (MATH7611)
- Mathematics LAB1 (MATH104)
- 아주희망 (course for freshmen) (CAJO114) (co-teaching with Prof. Uijin Jung)
- Differential Geometry (course in Graduate school of education) (11215)

- Calculus II (MATH103) (co-teaching with Prof. Dongseon Hwang)

- Topology (MATH341)
- Algebraic Topology II (MATH646)
- Industrial Mathematics Survey 2 (MATH672) (co-teaching with Prof. Boram Park)
- Mathematical Logic and Essay(course in Graduate school of education) (50171) (co-teaching with Prof. Ho Kyoung Ko)

- Differential Geometry (MATb35)
- Algebraic Topology I (MATH647)
- Industrial Mathematics Survey 1 (MATH671)
- 아주희망 (course for freshmen) (CAJO114) (co-teaching with Prof. Youngwoo Choi)

- Topics in Geometry (MATH432)
- Differential Geometry 1 (MATH638)
- Topology (course in Graduate school of education) (10156)

- Calculus I (MATH102)
- Differential Geometry (MATb35)
- Topics in Topology I (MATH741)
- Differential Geometry (course in Graduate school of education) (11215)

- Topology (MATH341)
- Algebraic Topology I (MATH647)
- Math Lab II (MAPLE program training course) (MATH105)

- Calculus I (MATH102) for two classes
- Number theory (course in Graduate school of education) (13603)

- Topology (MATH341)
- Engineering Mathematics A (MATH205)
- Topology (course in Graduate school of education) (10156)
- Identification of gifted in Mathematics (course in Graduate school of education) (50145) (co-teaching with Prof. Ho Kyoung Ko)

- Engineering Mathematics A (MATH205) for two classes
- Topics in Topology I (MATH741)
- Mathematics Problem Practice 1(course in Graduate school of education) (15524)

- Topics in Geometry (MATH432)
- Seminar in Topology I (MATH747)
- Mathematical Logic and Essay(course in Graduate school of education) (50171) (co-teaching with Prof. Ho Kyoung Ko)

- Engineering Mathematics A (MATH205) for two classes
- Discrete Mathematics (MATH285)
- Combinatorics and graph theory (course in Graduate school of education) (22504)
- Story-telling math for gifted students in math (course in Graduate school of education) (EDU5112) (co-teaching with Prof. Ho Kyoung Ko)

- Calculus II (MATH103)
- Topology (MATb41)
- Topology (course in Graduate school of education) (10156)

- Calculus I (MATH102) for two classes
- Seminar in Topology II (MATH748)
- Combinatorics and graph theory (course in Graduate school of education) (22504)

- Seminar in Topology I (MATH747)
- Math Programming (MATH106)
- Math Lab I (MAPLE program training course)(MATH105)
- Technology for Mathematics Education (course in Graduate school of education) (7004)

- Calculus I (MATH102) for two classes
- Algebraic Topology II (MATH646)
- Combinatorics and graph theory (course in Graduate school of education) (22504)

- Topology (MATH441)
- Algebraic Topology I (MATH635)

- Calculus I (for freshmen) (MATH102)
- Differential Geometry I (for graduate-course students) (1711)
- Math Lab I (MAPLE program training course) (MATH104)