activity
20182026
collaborators

12 papers

math.GT2026

Fox -Colorings as Fixed Points of Braid Representations

Neungjoo Goh, Suah Jeong, Seungbin Oh +1

Fox -colorings of knots and links admit a linear-algebraic description in terms of braid representations. For each braid we associate a representation $M : B_n \to \m…

math.GT2026

A diagrammatic approach to the three-page index

Hyungkee Yoo

The three-page index is an invariant that measures the complexity of representing a link in a three-page book. It is known that admits a linear upper bound in…

math.GT2026

New Upper Bounds on the Ribbonlength of Alternating Links with Bipartite Dual Graphs

Hyungkee Yoo

The ribbonlength of a link is a geometric invariant defined as the infimum of the ratio of the length to the width of a folded ribbon realization of the link. In this paper, we pro…

math.GT2025

Three-page indices of torus links

Useong Jang, Minseo Lee, Hyungkee Yoo

An arc presentation of a link is an embedding into the open book decomposition of with a finite number of pages. An important rule of arc presentations is that diffe…

math.GT2024

Linear Upper Bounds on the Ribbonlength of Knots and Links

Hyoungjun Kim, Sungjong No, Hyungkee Yoo

A knotted ribbon is one of physical aspect of a knot. A folded ribbon knot is a depiction of a knot obtained by folding a long and thin rectangular strip to become flat. The ribbon…

math.GT2024

Linking numbers of Montesinos links

Hyoungjun Kim, Sungjong No, Hyungkee Yoo

The linking number of an oriented two-component link is an invariant indicating how intertwined the two components are. Tuler proved that the linking number of a two-component rati…

math.CO2022

On the Laplacian spectrum of -symmetric graphs

Sunyo Moon, Hyungkee Yoo

For some positive integer , if the finite cyclic group can act freely on a graph , then we say that is -symmetric. In 1985, Faria showed that the multip…

math.GT2022

Petal number of torus knots using superbridge indices

Hyoungjun Kim, Sungjong No, Hyungkee Yoo

A petal projection of a knot is a projection of a knot which consists of a single multi-crossing and non-nested loops. Since a petal projection gives a sequence of natural numb…

math.GT2022

Ribbonlength of twisted torus knots

Hyoungjun Kim, Sungjong No, Hyungkee Yoo

The ribbonlength Rib of a knot is the infimum of the ratio of the length of any flat knotted ribbon with core to its width. A twisted torus knot is obtai…

math.GT2022

Folded ribbonlength of 2-bridge knots

Hyoungjun Kim, Sungjong No, Hyungkee Yoo

A ribbon is a two-dimensional object with one-dimensional properties which is related with geometry, robotics and molecular biology. A folded ribbon structure provides a complex st…

math.GT2018

Lattice stick number of spatial graphs

Hyungkee Yoo, Chaeryn Lee, Seungsang Oh

The lattice stick number of knots is defined to be the minimal number of straight sticks in the cubic lattice required to construct a lattice stick presentation of the knot. We sim…

math.GT2018

Bisected vertex leveling of plane graphs: braid index, arc index and delta diagrams

Sungjong No, Seungsang Oh, Hyungkee Yoo

In this paper, we introduce a bisected vertex leveling of a plane graph. Using this planar embedding, we present elementary proofs of the well-known upper bounds in terms of the mi…