Sang-il Oum delivered the plenary lecture at the 2019 Korean Mathematical Society Spring Meeting (대한수학회 봄 연구발표회) held at the Kangwon National University in Chuncheon on April 19-20, 2019. The title of his talk was “How to decompose a graph into a tree-like structure”.

## Jon-Lark Kim gave an introductory talk on Boolean functions with Artificial Neural Network

Jon-Lark Kim (김종락) from Sogang University presented a talk at Discrete Math Seminar on April 18, 2019. The title of his talk was “Introduction to Boolean functions with Artificial Neural Network”.

## Andreas Holmsen presented his work on an extremal problem on hypergraphs on March 12 at the discrete math seminar

Andreas Holmsen from KAIST gave a talk at Discrete Math Seminar on March 12, 2019 under the title “large cliques in hypergraphs with forbidden substructures.” His work extended a result of extremal graph theory due to Gyárfás, Hubenko, and Solymosi, answering a question of Erdős to hypergraphs and has interesting consequences in topological combinatorics and abstract convexity.

## DIMAG had its first workshop “2019-1 IBS Workshop on Graph Theory”

DIMAG had its first workshop “2019-1 IBS Workshop on Graph Theory” on February 11 and 12, 2019. There were 6 invited talks — Jeong Han Kim (KIAS), Cory T. Palmer (Univ. of Montana), Martin Balko (Charles Univ.), Dong Yeap Kang (KAIST), Boram Park (Ajou Univ.), and Dániel Gerbner (Alfréd Rényi Institute of Mathematics). We would like to thank all speakers and participants.

The talks are recorded but due to technical problems, only four talks are available online.

## Seog-Jin Kim presented his work on signed colouring and list colouring of k-chromatic graphs on January 28

Seog-Jin Kim from Konkuk University presented a talk at Discrete Math Seminar on January 28, 2019. The title of his talk was “Signed colouring and list colouring of k-chromatic graphs.”

## 2019-1 IBS Workshop on Graph Theory (Feb. 11-12, 2019). Registration due: Jan. 28

The Discrete Mathematics Group (DIMAG) at the Institute for Basic Science (IBS) will have its first workshop in Feb. 11-12, 2019. If you want to participate, then please register by January 28 on the website. We plan to provide accommodation for speakers and selected participants requested during the online registration.

- Title: 2019-1 IBS Workshop on Graph Theory
- Location: IBS, 2nd Floor of the Theory Building, Room B232 (Daejeon)
- Website: https://dimag.ibs.re.kr/event/2019-1-graph-theory/
- Organizer: Sang-il Oum, Younjin Kim

## Eun Jung Kim gave a talk on her recent work on the parametrized complexity on January 4

Eun Jung Kim (김은정) from LAMSADE, CNRS, Paris gave a talk at Discrete Math Seminar on January 4, 2019. The title of her talk was “New algorithm for multiway cut guided by strong min-max duality”.

## Joonkyung Lee presented his work on Sidorenko’s conjecture on January 3

Joonkyung Lee (이준경) from University of Hamburg gave a talk at Discrete Math Seminar on January 3, 2019. The title of his talk was “Sidorenko’s conjecture for blow-ups”. (This was the first talk at the room B232.)

## Hong Liu gave the second discrete math seminar talk at IBS DIMAG

Hong Liu from University of Warwick, UK gave the discrete math seminar talk at DIMAG on his recent work “polynomial Schur’s theorem” on December 13, 2018.

## The first seminar talk at DIMAG was given by Tony Huynh on December 10

Tony Huynh from Université libre de Bruxelles became the first person to give a talk at discrete math seminar at DIMAG on December 10, 2018. He talked about his recent work “A tight Erdős-Pósa function for planar minors” (SODA’19).