On October 12, 2021, Joonkyung Lee (이준경) from the Hanyang University gave a talk about the majority dynamics on sparse random graphs. The title of his talk was “Majority dynamics on sparse random graphs“.

## Paul Seymour gave an online talk on the polynomial 𝜒-boundedness of graph classes at the Virtual Discrete Math Colloquium

On October 8, 2021, Paul Seymour from Princeton University gave an online talk at the Virtual Discrete Math Colloquium on the polynomial 𝜒-boundedness of graph classes. The title of his talk was “Polynomial bounds for chromatic number“.

## Eunjin Oh (오은진) gave a talk on a parameterized complexity of the feedback vertex set problem on unit disk graphs at the Discrete Math Seminar

On October 5, 2021, Eunjin Oh (오은진) from POSTECH gave a talk at the Discrete Math Seminar on the parameterized complexity of the feedback vertex set problem on unit disk graphs at the Discrete Math Seminar. The title of her talk was “Feedback Vertex Set on Geometric Intersection Graphs“.

## Péter Pál Pach gave an online talk on the solution of the Alon-Jaeger-Tarsi conjecture at the Virtual Discrete Math Colloquium

On September 30, 2021, Péter Pál Pach from the Budapest University of Technology and Economics gave an online talk at the Virtual Discrete Math Colloquium on the solution of the Alon-Jaeger-Tarsi conjecture for all finite fields of size more than 61 but not equal to 79. The title of his talk was “The Alon-Jaeger-Tarsi conjecture via group ring identities“.

## Kevin Hendrey gave a talk on the edge density of graphs having no H-minor for a sparse graph H at the Discrete Math Seminar

On September 28, 2021, Kevin Hendrey from the IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar on the supremum of the edge density of graphs not having H-minors, when H is in a graph class admitting strongly sublinear separators. The title of his talk was “Extremal functions for sparse minors“.

## The IBS Discrete Mathematics Group (DIMAG) Postdoctoral Research Fellowship (Due: December 5, 2021)

The IBS Discrete Mathematics Group (DIMAG) in Daejeon, Korea invites applications for two postdoctoral research fellowship positions.

URL: https://dimag.ibs.re.kr/hiring/

DIMAG is a research group that was established in December 1, 2018 at the Institute for Basic Science (IBS), led by Prof. Sang-il Oum. DIMAG is located at the headquarters of the Institute for Basic Science (IBS) in Daejeon, South Korea, a city of 1.5 million people.

The position is available for individuals who are within the first five years after obtaining their Ph.D. at the date of appointment or expecting to obtain a Ph.D. within three months from the date of appointment. Successful candidates for postdoctoral research fellowship positions will be new or recent Ph.D.’s with outstanding research potential in all fields of **discrete mathematics** with emphasis on **structural graph theory, extremal graph theory, combinatorial optimization, matroid theory, or fixed-parameter tractable algorithms**.

This appointment is for two years, and the starting salary is no less than KRW 57,000,000. The appointment is one time renewable up to 3 years in total contingent upon the outstanding performance of the researcher. The expected appointment date is September 1, 2022. This is a purely research position and will have no teaching duties.

A complete application packet should include:

- AMS standard cover sheet (preferred) or cover letter (PDF format)
- Curriculum vitae including a publication list (PDF format)
- Research statement (PDF format)
- Consent to Collection and Use of Personal Information (PDF file)
- At least 3 recommendation letters

For full consideration, applicants should email items 1, 2, 3, and 4 and arrange their recommendation letters emailed to **dimag@ibs.re.kr** by **December 5, 2021, Sunday**.

Recommendations letters forwarded by an applicant will not be considered.

DIMAG encourages applications from individuals of diverse backgrounds.

*In the unlikely event of closing the group, the employment contract will be terminated accordingly. For Korean citizens who have not yet completed their military duty: IBS는 병역특례지정기관입니다. IBS is a designated institute for alternative military service.*

## Dabeen Lee (이다빈) gave a talk characterizing the submodular structure in the mixed-integer program arising from joint linear chance-constrained programs at the Discrete Math Seminar

On September 7, 2021, Dabeen Lee (이다빈) from the IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar characterizing the submodular structure in the mixed-integer program arising from joint linear chance-constrained programs with random right-hand sides and finite sample space. The title of his talk is “Mixing sets, submodularity, and chance-constrained optimization“.

## Cheolwon Heo (허철원) gave a talk on even-cycle matroids at the Discrete Math Seminar

On August 31, 2021, Cheolwon Heo (허철원) gave a talk on representations of even-cycle matroids at the Discrete Math Seminar. He finished his Ph.D. recently from the University of Waterloo and begins his postdoc position at the Applied Algebra and Optimization Research Center (AORC) of Sungkyunkwan University on September 1, 2021. The title of his talk is “Representations of even-cycle matroids”.

## Eun Jung Kim gave a talk on an approximation algorithm for the minimum weight vertex set to hit all bonds of size at least k at the Discrete Math Seminar

On August 24, 2021, Eun Jung Kim (김은정) from LAMSADE, CNRS gave a talk at the Discrete Math Seminar on an approximation algorithm for finding the minimum weight vertex set hitting all bonds of size at least k in a graph. The title of her talk was “A Constant-factor Approximation for Weighted Bond Cover“.

## Petr Hliněný gave an online talk on bounding the twin-width of a partially ordered set in terms of the poset width at the Virtual Discrete Math Colloquium

On August 18, 2021, Petr Hliněný from the Masaryk University, Czech gave an online talk at the Virtual Discrete Math Colloquium on a linear upper bound of the twin-width of a partially ordered set in terms of the poset width. The title of his talk is “Twin-width is linear in the poset width“.