News

November 8, 2022November 8, 2022

Jungho Ahn (안정호) gave a talk at the Discrete Math Seminar on the almost linear kernel for packing and covering problems on nowhere dense classes of graphs

On November 8, 2022, Jungho Ahn (안정호) from KAIST and the IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar on a unified framework to create a polynomial-time preprocessing algorithm (kernel) for various packing and covering problems reducing the input instance to an equivalent instance of almost linear size on nowhere dense classes of graphs. The title of his talk was “Unified almost linear kernels for generalized covering and packing problems on nowhere dense classes“.

November 8, 2022November 8, 2022

Welcome Suyun Jiang (江素云) from Jianghan University, a new visiting scholar in the IBS Extremal Combinatorics and Probability Group

The IBS discrete mathematics group welcomes Dr. Suyun Jiang (江素云), a new visiting scholar from Jianghan University, China. She is visiting the IBS extremal combinatorics and probability group for 21 months from November 4, 2022. She received her Ph.D. from Shandong University in China and is currently an assistant researcher in the School of Artificial Intelligence, Jianghan University, Wuhan, China.

November 4, 2022November 4, 2022

The 2022 DIMAG-ECOPRO Joint Internal Workshop was held in Yeosu on October 31-November 3, 2022

The IBS Discrete Mathematics Group (DIMAG) had its third internal workshop with the new IBS Extremal Combinatorics and Probability Group (ECOPRO) at the Yeosu Expo UTOP Marina Hotel & Resort under the name “The 2022 DIMAG-ECOPRO Joint Internal Workshop” on October 31-November 3, 2022. Participants include almost all current members of DIMAG and ECOPRO, Minki Kim from GIST, Cheolwon Heo from Sungkyunkwan University, Eun-Kyung Cho from Hankuk University of Foreign Studies, and Semin Yoo from KIAS. Every participant presented open problems and had active discussions.

October 18, 2022October 18, 2022

Florent Koechlin gave a talk on properties of uniformly chosen random expressions at the Discrete Math Seminar

On October 18, 2022, Florent Koechlin from LORIA, INRIA, France gave a talk at the Discrete Math Seminar on the reducibility of uniformly random expressions. The title of his talk was “Uniform random expressions lack expressivity“.

October 13, 2022October 13, 2022

“2022 Combinatorics Workshop” (2022 조합론 학술대회) was held from September 30 to October 1, 2022 at GIST, Gwangju

The 2022 Combinatorics Workshop (2022 조합론 학술대회) was held from September 30, 2022 to October 1, 2022 at GIST, Gwangju. There were 4 invited talks and 9 contributed talks.

Invited talks

Andeas Holmsen, KAIST
Seog-jin Kim (김석진), Konkuk University
Seung Jin Lee (이승진), Seoul National University
Hayan Nam (남하얀), Duksung Women’s University

Contributed talks

Zixiang Xu, IBS ECOPRO
Mark Siggers, KNU
Alexander Clifton, IBS DIMAG
Stijn Cambie, IBS ECOPRO
Jun Gao, IBS ECOPRO
Minho Cho (조민호), KAIST
Nika Salia, IBS ECOPRO
Jaeseong Oh, KIAS
Jungho Ahn, KAIST / IBS DIMAG

Organizing Committee

Jeong Ok Choi (최정옥), GIST
Minki Kim (김민기), GIST
Sangwook Kim (김상욱), Chonnam National University
Hong Liu, IBS Extremal Combinatorics and Probability Group

Host and Sponsors

IBS Extremal Combinatorics and Probability Group
National Research Foundation of Korea

October 12, 2022October 12, 2022

Nika Salia gave a talk on the maximum number of bicliques in a graph without an even cycle of a fixed length at the Discrete Math Seminar

On October 11, 2022, Nika Salia from the IBS Extremal Combinatorics and Probability Group gave a talk at the Discrete Math Seminar on the maximum number of bicliques in a graph without an even cycle of a fixed length at the Discrete Math Seminar. The title of his talk was “Exact results for generalized extremal problems forbidding an even cycle“.

October 5, 2022September 3, 2023

Zixiang Xu (徐子翔) gave a talk on Turán numbers of bipartite graphs at the Discrete Math Seminar

On October 4, 2022, Zixiang Xu (徐子翔) from the IBS Extremal Combinatorics and Probability Group gave a talk at the Discrete Math Seminar on the Turán numbers of bipartite graphs and recent approaches. The title of his talk was “On the degenerate Turán problems“.

October 3, 2022October 3, 2022

Santiago Guzmán-Pro gave an online talk on characterizing hereditary graph classes definable by forbidden orientations at the Virtual Discrete Math Colloquium

On September 29, 2022, Santiago Guzmán-Pro from the Universidad Nacional Autónoma de México (UNAM), Mexico gave an online talk on characterizing hereditary graph classes definable by forbidden orientations at the Virtual Discrete Math Colloquium. The title of his talk was “Local expressions of graphs classes“.

September 28, 2022September 28, 2022

Alexander Clifton gave a talk on the existence of a monochromatic increasing sequence with all gaps in a fixed set in any coloring of the set of positive integers at the Discrete Math Seminar

On September 27, 2022, Alexander Clifton from the IBS Discrete Mathematics Group gave a talk on the existence of a monochromatic increasing sequence with all gaps in a fixed set in any coloring of the set of positive integers at the Discrete Math Seminar. The title of his talk was “Ramsey Theory for Diffsequences“.

September 14, 2022September 14, 2022

Sebastian Wiederrecht gave a talk on the minor obstruction to admitting a tree decomposition into graphs each having bounded genus after removing a bounded number of apex vertices at the Discrete Math Seminar

On September 13, 2022, Sebastian Wiederrecht from the IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar on the minor obstruction to admitting a tree decomposition into graphs each having bounded genus after removing a bounded number of apex vertices and its application to the characterization of minor-closed graph classes admitting efficient algorithms to count perfect matchings. The title of his talk was “Killing a vortex“.