Ozone is usually produced by the dielectric barrier discharge (DBD) method. The dielectric barrier discharge can be divided into two categories: volume discharge and surface discharge. In the surface discharge, a ceramic plate is used as a dielectric barrier. As an advanced form of single SDBD, double SDBD was proposed, in which striped electrodes were coated on both sides of the ceramic plate. Double SDBD can simultaneously generate two plasma zones on both sides of the ceramic plate to improve energy efficiency compared to single SDBD. However, it is difficult to realize the cooling of the discharge device.

A previous study proposed a double SDBD reactor in which two silver mesh electrodes were coated on one side of an enameled steel plate. However, an enameled steel plate is easy to deform during the fabrication process and it is difficult to make the discharge device larger. In addition, a silver electrode is not practical because of its low resistance to the oxidation of ozone.

Kim Jong Guk, a researcher at the Institute of Nano Science and Technology, has proposed a cylindrical double SDBD device.

The proposed discharge device can simultaneously produce ozone at both the high voltage electrode and the grounded electrode, thus showing great advantages in getting high ozone concentration.

The optimized reactor ensures ozone generation efficiency of 339g/(kW·h) and ozone concentration of 82g/(N·m3).

You can find the details in his paper “Implementation of Double Surface Dielectric Barrier Discharge with Enamel Ozone Tube” in “Proceedings of KUTIC-2025”.

Gliding arc discharge (GAD) generates plasma with relatively high electron density and power, and also provides high operating pressure, low fabrication cost and excellent reaction selectivity. In particular, its power levels higher than other atmospheric pressure non-equilibrium discharges such as dielectric barrier or corona discharges have constantly expanded its applications in combustion support, surface treatment, fuel reforming, chemical synthesis, environmental remediation, etc.

Kim Yong Jun, a researcher at the Faculty of Physical Engineering, has proposed a type of gas discharge defined as a gliding arc-microwave hybrid discharge (also called microwave enhanced gliding arc discharge or gliding arc assisted microwave discharge), and experimentally investigated its coordination effects for generating plasma.

The gliding arc acts as an igniter for generating and maintaining microwave plasma at atmospheric pressure, while the microwave-enhanced gliding arc discharge indicates expansion of the length and bulk of plasma flame, which has a positive effect on the residence time and immersion of reactants in the plasma.

The proposed hybrid discharge can be applied to different fields such as chemical synthesis, surface treatment, fuel reforming and environmental improvement as it can generate efficient and bulk plasma with different temperatures and good reaction selectivity at atmospheric pressure.

You can find the details about it in his paper “Coordination effect in generating plasma by gliding arc-microwave hybrid discharge in atmospheric-pressure air” in “Applied Physics Letters” (NI).

Swinging, one of the folk games enjoyed by the Korean women from olden times, has been conducted on folk holidays in spring and autumn.

Swinging had different names in different areas: kuli, kulgi, hulgi, kunggu, kundi and chuchon. In those days, swing ropes were fixed to the branches of shade trees and there was a footboard between the ropes for easy standing. Safety wristbands made of soft cloth were tied to the ropes so that people on the swing could propel themselves vigorously without anxiety in order to reach the bell.

Swinging was classified into single swinging (one person on the swing) and pair swinging (two people face to face on the swing). Single swinging was often preferred for a match.

Win and defeat was decided in several ways. At first, as the ropes were fixed to the thick boughs, kicking or catching in one’s mouth the twigs or sprigs set as a target in the front, or measuring the maximum height of the bell attached to the holder by elevating it were common. After that, a measuring tape with scales attached to the bottom of the footboard was used to decide winners by reading the marks at the swing holder.