Author: gradseminar

The 22nd KMGS will be held on June 20th, Tuesday, at Natural Science Building (E6-1) Room 1501.
We invite speakers  Hyukpyo Hong (홍혁표) from the Dept. of Mathematical Sciences, KAIST, and   Dae Wook Kim (김대욱) from Dept. of Mathematics, University of Michigan, Ann Arbor. The abstract of the talk is as follows.

Slot (PM 2:00~PM 3:00)
[Speaker] Hyukpyo Hong (홍혁표) from Dept. of Mathematical Sciences, KAIST, supervised by Prof. Jae Kyoung Kim (김재경 교수님),
 Dae Wook Kim (김대욱) from Dept. of Mathematics, University of Michigan, Ann Arbor  
[Title] 해외 수학과 포닥 지원 및 생활 후기 / Experiences of applying for and living as a postdoc.  
[Discipline] General Topic  
[Abstract] 한국의 수학과 박사과정 학생이 해외로 포닥을 지원하는 방법, 그리고 2년간의 포닥 생활 후기에 대해 발표합니다. 포닥 지원 시기와 절차는 어떤지, 포닥 지원을 위한 CV, 추천서, research statement, teaching statement 등을 어떻게 준비하는 지 설명드립니다.해외 정착, 기존 연구 마무리 및 포닥으로서의 새로운 연구 시작 방법에 대해 설명드립니다. 이 발표는 University of Wisconsin, Madison의 Van Vleck assistant professor 오퍼를 받은 홍혁표 학생과 University of Michigan, Ann Arbor에서 2년간 James Van Loo assistant professor로 근무한 김대욱 박사가 진행합니다. 
We will present on how a doctoral student in the field of mathematics in Korea can apply for a postdoctoral position abroad and share the experience of living as a postdoc for two years. We will explain the timing and procedures for applying for a postdoc position, as well as how to prepare a CV, recommendation letters, research statement, teaching statement, and other documents required for the application. Also, we will provide information on how to settle down in a foreign country, wrap up existing research, and start new research as a postdoc. This presentation will be conducted by Hyukpyo Hong, a student who recently received an offer for the Van Vleck Assistant Professor position at the University of Wisconsin, Madison, and Dr. Dae Wook Kim, who worked as a James Van Loo Assistant Professor at the University of Michigan, Ann Arbor for two years.
[Language] Korean

The 21st KMGS will be held on June 1st, Thursday, at Natural Science Building (E6-1) Room 1501.
We invite a speaker Hansol Kim from the Dept. of Mathematical Sciences, KAIST.
The abstract of the talk is as follows.

Slot (AM 11:50~PM 12:30)
[Speaker] 김한솔 (Hansol Kim)  from Dept. of Mathematical Sciences, KAIST, supervised by Prof. 임보해 교수님 (Bo-Hae Im)
[Title] Problems on Torsion Subgroups of Elliptic Curves over Number Fields 
[Discipline] Number Theory
[Abstract]
We introduce elliptic curves, their Mordell-Weil group structure, and isogenies over number fields. At the last of the talk, some results on the torsion subgroups of Mordell-Weil groups of elliptic curves defined over a number field will be given.The results are joint works with my advisor Bo-Hae Im.
[Language] Korean 

The 20th KMGS will be held on May 18th, Thursday, at Natural Science Building (E6-1) Room 1501.
We invite a speaker Jungho Ahn from the Dept. of Mathematical Sciences, KAIST.
The abstract of the talk is as follows.

Slot (AM 11:50~PM 12:30)
[Speaker] 안정호 (Jungho Ahn) from Dept. of Mathematical Sciences, KAIST, supervised by Prof. 엄상일 교수님(Sang-il Oum)
[Title] Introduction to Kernelization
[Discipline] Graph Theory, Complexity Theory
[Abstract]
We introduce concepts of parameterized complexity, especially, kernelization. Kernelization is a polynomial-time preprocessing algorithm that converts a given instance for a problem to a smaller instance while keeping the answer to the problem. Delicate kernelization mostly boosts the speed of solving the problem. We explain standard techniques in kernelizations, for instance, the sunflower lemma. Most optimization problems can be reformulated in the Hitting Set problem format, and the sunflower lemma gives us a simple yet beautiful kernelization for the problem. We further introduce our recent work about the Hitting Set problem on sparse graph classes.
[Language] Korean but English if it is requested.

The 19th KMGS will be held on May 11th, Thursday, at Natural Science Building (E6-1) Room 1501.
We invite a speaker Doyoung Choi from the Dept. of Mathematical Sciences, KAIST.
The abstract of the talk is as follows.

Slot (AM 11:50~PM 12:30)
[Speaker] Doyoung Choi(최도영) from Dept. of Mathematical Sciences, KAIST, supervised by Prof. Yongnam Lee (이용남 교수님)
[Title] Degree of the 3-secant variety
[Discipline] Algebraic geometry
[Abstract] 
In this talk, we present a formula for the degree of the 3-secant variety of a nonsingular projective variety embedded by a 3-very ample line bundle. The formula is provided in terms of Segre classes of the tangent bundle of a given variety. We use the generalized version of double point formula to reduce the calculation into the case of the 2-secant variety. Due to the singularity of the 2-secant variety, we use secant bundle as a nonsingular birational model and compute multiplications of desired algebraic cycles.
[Language] Korean

The 18th KMGS will be held on April 6th, Thursday, at Natural Science Building (E6-1) Room 1501.
We invite a speaker Kyunghan Choi from the Dept. of Mathematical Sciences, KAIST.
The abstract of the talk is as follows.

Slot (AM 11:50~PM 12:30)
[Speaker] Kyunghan Choi(최경한) from Dept. of Mathematical Sciences, KAIST, supervised by Prof. Yongjung Kim (김용정 교수님)
[Title] Pattern formations by biological diffusion : chemotaxis model 
[Discipline] Analysis 
[Abstract]
In this seminar, we will talk about the chemotaxis model, which is a diffusion model for biological dispersion. Chemotaxis is the movement of biological organisms in response to chemical stimuli. The chemotaxis model has nonlinear diffusion with no reaction term and has been extensively studied in the sense of a diffusion model for heterogeneous media. The nonlinear diffusion alone makes it possible to allow us to observe various spatial patterns. We will see what kind of pattern formation the model provides and what mathematical problems this model can be applied to. 
[Language] Korean but English if it is requested