Feb 9 to 21, 2020

Main Organizers:

• Ilkyoo Choi (Hankuk University of Foreign Studies)
• Suil O (SUNY-Korea)

Additional Organizers for winter of 2020:

• Ringi Kim (KAIST)
• Boram Park (Ajou University)
• Jongyook Park (KNU)

• KB Ingenium

Accomodation

• KB Ingenium

• Feb 9 (Sunday)
• 14:00 -- 16:00 registration & check in
• 16:00 -- 18:00 research session

Feb 10 (Monday)

• 10:00 -- 12:00 introduction and problem session (mandatory)
• 12:00 -- 14:00 lunch
• 14:00 -- 18:00 afternoon research session
• 18:00 -- banquet

Feb 11 (Tuesday)

• 10:00 -- 12:00 morning research session
• 12:00 -- 14:00 lunch
• 14:00 -- 15:00 lecture 1 (Ringi Kim): Some questions about strong clique number

.A strong chromatic index of a graph G is the minimum number of induced matchings in G covering all edges. The Strong Edge Coloring Conjecture states that the strong chromatic index of G is at most 5/4D(G)^2 where D(G) is the maximum degree of G. Faudree, Gyrfs, Schelp, and Tuza raised a weaker version of the strong edge coloring conjecture stating that the clique number of the square of the line graph of G is at most 5/4 D(G)^2. In this talk, we discuss recent results about this conjecture, and show that the conjecture is true for some class of graphs.

• 15:00 -- 18:00 afternoon research session
• 18:00 -- dinner

Feb 12 (Wednesday)

• 10:00 -- 12:00 morning research session
• 12:00 -- 14:00 lunch
• 14:00 -- 14:30 lecture 2 (Semin Oh): Analysis of Senior Health Data Using Decision Tree Model

.We will analyze blood pressure data collected from the center for senior citizens in Yangsan, South Gyeongsang Province. Based on the blood pressure data, risk of blood pressure in future is predicted by the decision tree model. We analyze the results.

• 14:30 -- 18:00 afternoon research session
• 18:00 -- dinner

Feb 13 (Thursday)

• 10:00 -- 12:00 morning research session
• 12:00 -- 14:00 lunch
• 14:00 -- 14:30 lecture 3 (Hyunsoo Cho): self-conjugate (s,s+d,...,s+pd)-core partitions

.In this talk, we introduce the poset structure and abacus diagram for self-conjugate (s,s+d,...,s+pd)-core partitions. Also, we give a lattice path interpretation for self-conjugate (s,s+d,...,s+pd)-core partitions.

• 14:30 -- 18:00 afternoon research session
• 18:00 -- dinner

Feb 14 (Friday)

• 10:00 -- 12:00 morning research session
• 12:00 -- 14:00 lunch
• 14:00 -- 18:00 afternoon research session
• 18:00 -- dinner

Feb 15 (Saturday)

• 10:00 -- 14:00 Free
• 14:00 -- 18:00 research session

Feb 16 (Sunday)

• 10:00 -- 14:00 Free
• 14:00 -- 18:00 research session

Feb 17 (Monday)

• 10:00 -- 12:00 morning research session
• 12:00 -- 14:00 lunch
• 14:00 -- 14:30 lecture 4 (Jeong Rye Park): On integral graphs

.An integral graph is a graph whose adjacency matrix has only integral eigenvalues. There are several studies on integral graphs. All integral graphs with maximum vertex-degree 3 are known; exactly 20 of them are connected, and of these graphs 13 are regular. In addition, all non-regular integral graphs with maximum vertex-degree 4 are known; exactly 106 of them are connected, and of these graphs 13 are non-bipartite. There are also partial results concerning 4-regular integral graphs, but this case is still open. We present a survey of results on integral graphs.

• 14:30 -- 18:00 afternoon research session
• 18:00 -- dinner

Feb 18 (Tuesday)

• 10:00 -- 18:00 research activity
• 18:00 -- banquet

Feb 19 (Wednesday)

• 10:00 -- 12:00 morning research session
• 12:00 -- 14:00 lunch
• 14:00 -- 14:30 lecture 5 (Ilkyoo Choi): Brick partition problems in 3-dimensions

.A d-dimensional brick is a product of intervals. Given a brick B, a brick partition of B is a partition of B into bricks. A brick partition P of a d-dimensional brick is k-piercing if every axis-parallel line intersects at least k bricks in P. We investigate the minimum size p(d, k) of a k-piercing brick partition of a d-dimensional brick.

• 14:30 -- 18:00 afternoon research session
• 18:00 -- dinner

Feb 20 (Thursday)

• 10:00 -- 12:00 morning research session
• 12:00 -- 14:00 lunch
• 14:00 -- 14:30 lecture 6 (JiSun Huh): On the number of equivalence classes arising from partition involutions

.In this talk, we give relations between the number of equivalence classes in the set of partitions arising from an involution and the number of partitions satisfying a certain parity condition, for various sets of partitions. We examine the number of equivalence classes arising from the involutions on ordinary partitions, overpartitions, partitions with distinct odd parts, partitions into distinct parts, unimodal sequences with a unique marked peak, and partitions with distinct even parts.

• 14:30 -- 18:00 afternoon research session
• 18:00 -- dinner

Feb 21 (Friday)

• 10:00 -- 12:00 activity report (mandatory)
• 12:00 -- 14:00 lunch