UNIST Shines with Two Academic Stars: Two Professors Selected for "Top 50 Outstanding Achievements"

Professor Kyudong Choi, First to Establish the Theory of "Vortex Stability" Behind Typhoon Phenomena
Professor Jaehwa Lee, Proposes Biomimetic "High-Efficiency Propulsion" for Underwater Robots

They were thought to be solely focused on research, but they also received an award.

Two leading professors from UNIST have passed the Ministry of Education's rigorous review and were selected for the "Top 50 Outstanding Achievements in Academic Research Support."

UNIST (President Chong Rae Park) announced on December 10 that Kyudong Choi, Professor of Mathematical Sciences, and Jaehwa Lee, Professor of Mechanical Engineering, were selected for the Ministry of Education's "Top 50 Outstanding Achievements in Academic Research Support."

This year, 245 research achievements from the 2024 Academic Research Support Project were submitted through open calls and recommendations. After evaluation based on originality, excellence, and academic contribution, 50 were selected.

The selected achievements were awarded the Minister of Education Award, and the award ceremony was held on December 9 at the Grand InterContinental Hotel in Seoul.

Kyudong Choi, Professor of Mathematical Sciences, solved a long-standing problem in fluid rotational motion that had remained unsolved for 130 years. The model that describes a flow where energy gathers in a circular motion and spins rapidly, like a typhoon, is called the "Hill spherical vortex." The challenge was that the boundary of this flow is discontinuous, making it difficult to mathematically prove its stable existence.

Kyudong Choi, Professor of Mathematical Sciences at UNIST.

Professor Choi's team proposed a new computational method that implements boundary conditions closer to those found in nature. By devising a way to smoothly connect the "discontinuous transition zones" that existing theories struggled to handle, they enabled the resolution of complex boundary problems.

Based on this, they became the first in the world to rigorously prove that spherical vortices can maximize kinetic energy and exist stably under certain conditions.

Professor Kyu-Dong Choi's research diagram mathematically proved the existence of spherical vortices discovered by Hill.

This achievement is significant because it theoretically established the stability of three-dimensional localized vortices. The paper was published in one of the top mathematical journals, Communications on Pure and Applied Mathematics (CPAM), and also received the Korean Mathematical Society's Paper Award.

Professor Choi stated, "This research demonstrates the international competitiveness of Korea's basic mathematics," adding, "I hope it will contribute to expanding the theoretical foundation in various fields, including fluid stability theory and climate change research."

Jaehwa Lee, Professor of Mechanical Engineering, discovered a new principle of underwater propulsion from the swimming method of manta rays. Unlike conventional active flexibility, which controls the entire body, he focused on passive flexibility, where only the leading edge of the manta ray is controlled and the rest is left to interact with the fluid.

Jaehwa Lee, Professor of Mechanical Engineering.

The research team confirmed that this method creates strong vortex structures from the edges to the body of the manta ray and maintains positive pressure even at high speeds.

As a result, it can generate greater thrust with less energy, and the study is recognized for presenting a new efficiency-oriented paradigm, distinct from conventional full-body actuation methods. These findings were published in the world-renowned fluid dynamics journal, Physics of Fluids.

Research illustration by Professor Lee Jaehwa, (a) Time-dependent vortex structure changes around a manta ray with active flexibility and (b) with passive flexibility.

Professor Lee commented, "Collaboration and interdisciplinary research with fellow researchers were a tremendous help," and added, "We plan to expand our research into underwater robotics, such as autonomous underwater vehicles, underwater reconnaissance robots, and biomimetic propulsion systems, by integrating AI-based control technologies that enable adaptation to surrounding environments."

President Chong Rae Park emphasized, "The achievements of these two researchers are examples of solving fundamental mathematical problems and presenting innovative engineering technologies," adding, "UNIST's strategy for converging basic and applied research is producing tangible results."

This content was produced with the assistance of AI translation services.