Papers by Author: Do Young Byun

Abstract: We propose to use electrostatic drop-on-demand devices, with precise metering and accurate delivery capabilities, to manipulate single-walled carbon nanotubes suspended in solution. The conductivity of the solution increases significantly by the addition of anionic surfactants and nanotubes, generating favorable conditions for electrostatic ejection. This technique could find applications, combined with chemical functionalization, in the fabrication of carbon nanotube field emission devices as well as electronic circuits. hanseoko@yurim.skku.ac.kr

Abstract: In this study we have experimentally and numerically analyzed the flapping mechanism and wing kinematics of coleoptera (Propylea japonica Thunberg). Using digital high speed camera, we captured the continuous wing kinematics and visualized the flight motion of the free-flying coleoptera. The experimental visualization shows that the elytra flapped concurrently with the main wing both in the downstroke and upstroke motions. In order to define the wing kinematics of coleoptera, the displacement of a wing cross section (50% span-wise) was measured for each sequence of the wing motion. Using these data, the flight motion of coleoptera was numerically simulated to investigate the aerodynamic performance. The computational aerodynamic simulation shows that leading edge vortex shedding plays a key role in generating lift to keep the insect aloft.