Key to Success by a Single Stroke

Jo May 30, 2025

The research group led by Associate Prof. Kim Sung Chan, an institute head at the Faculty of Communications, has developed an aerological observation system, thus providing a scientific guarantee for timely coping with disastrous abnormal weather.

Influence of Surface Defects on Motion of Magnetic ...

Jo May 30, 2025

The time-dependent Ginzburg-Landau (TDGL) equations are a useful computational tool for characterizing the spatiotemporal variance of an order parameter that represents the phase transition in mesoscopic type-II superconductors. Especially, they are used to simulate the dynamics of magnetic vortex for designing superconducting materials with high critical current density.

Therefore, simulation of type-II superconductors using TDGL equations is essential for understanding magnetic vortex dynamics and studying superconducting critical characters such as critical current density and critical magnetic field. Numerical simulations for it are conducted by the finite difference method (FDM), the finite element method (FEM), the lattice Boltzmann method (LBM), etc.

Ryu Yu Gwang, a researcher at the Faculty of Physical Engineering, has investigated the influences of surface defects on the motion of magnetic vortices in a mesoscopic type-II superconductor with randomly distributed pinning centers through the simulations of TDGL equations by using COMSOL Multiphysics.

Two kinds of surface defects are located in the boundary: one is pinning centers and the other is geometric defects along with pinning centers.

In the simulation, he analyzed the magnetization curves, the vorticity and the density of superconducting electrons for both different contents of pinning centers and various geometric defects.

For the pinning centers as surface defects, the maximum magnetization values as a function of the contents exponentially decrease, and the field where the first vortex penetrates and the field where the complete transition from superconducting to a normal state in the system occurs are reduced.

For the geometric defects as surface defects, the density of superconducting electrons and the magnetization curves depend on their size and form. In addition, a threshold in the size of geometric defects in which the motion of vortices and vorticity change, exists.

You can find the details in his paper “The Influence of Surface Defects on Motion of Magnetic Vortices in Mesoscopic Type-II Superconductor with Randomly Distributed Pinning Centers” in “Journal of Superconductivity and Novel Magnetism” (SCI).

Simple Scoring System to Predict Urinary Tract Infe...

Jo May 29, 2025

Stroke remains a tremendous public health burden with approximately 795 000 people affected every year. Stroke is the leading cause of major long-term disability of adults and the third leading cause of death in developed countries. Urinary tract infection is a frequent problem after stroke.

Although prior scoring systems for UTI after stroke have been developed, Pak In Hui, a researcher at the Faculty of Biology and Medicine Engineering, has developed a simple scoring system of our own for all types of stroke.

The study was designed on retrospective data. The population included 1 496 patients with stroke who were admitted at the Neurology Department of Hospital of Pyongyang University of Medical Sciences between January, 2010 and August, 2019. The patients were diagnosed by means of CT and MRI.

You can find the details in her paper “The Development of Simple Scoring System to Predict Urinary Tract Infection (UTI) in Patients with Stroke” in “International Journal of Endocrinology” (SCI).