• Proceedings of the KIEE Conference
• /
• 2002.07c
• /
• pp.1878-1880
• /
• 2002

In this paper, electromagnetic waves radiated from discharge at three-type electrodes (needle-plane, plane-plane and sphere-plane electrode) using DC power source in air measured and the peculiar patterns of their spectra are reported. The radiated electrodmagnetic waves were measured in bandwidth of VHF($30{\sim}230$[MHz]) using a biconcal antenna and a spectrum analyzer. Frequency spectrum distribution of radiated electromagnetic wave was revealed under 50[MHz] at positive DC, and high electric field was shown at 45[MHz] frequency band. But, it was revealed under 70[MHz] frequency band at negative DC under plane-plane electrodes and sphere-plane electrodes, and high electric field was shown at 55 [MHz] frequency band.

• The Journal of the Acoustical Society of Korea
• /
• v.21 no.4
• /
• pp.183-183
• /
• 2002

In this paper, the strong in-plane vibration has been experimentally observed at the end of a finite cylindrical shell. The strong in-plane vibration was generated by the evanescent wave field, which was excited along about half the length of the shell. The evanescent waves were generated due to mode conversion of elastic waves at the ends of the cylindrical shells.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2005.07a
• /
• pp.436-436
• /
• 2005

We have investigated electro-optical properties of an in-plane switching cholesteric liquid crystal display (LCD). Planar and focal-conic texture changes re induced by application of an in-plane electric field.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2005.07a
• /
• pp.520-521
• /
• 2005

To observe the orientation of carbon nanotubes (CNTs) dispersed in nematic liquid crystal (NLC), CNT-doped homogeneously-aligned NLC cells driven by in-plane field was fabricated. The CNTs were aligned with a LC director in the initial state, whereas the CNTs disturbed the LC director above critical ac field. We observed motional textures in the form of vertical stripes in the local area between electrodes, which were associated with a deformation of the LC director orientation. This suggests that CNTs start to vibrate three dimensionally with translational motion. The hysteresis studies of voltage-dependent transmittance under dc electric field show that the amount of residual dc is greatly reduced due to ion trapping by CNT.

• Journal of Magnetics
• /
• v.18 no.2
• /
• pp.155-158
• /
• 2013

FeCoB films were being prepared on a Ru underlayer by using the oblique incidence of sputtered and back-scattered particles which have a high in-plane magnetic anisotropy field $H_k$ above 400 Oe. It is suitable to attain such deposition condition when facing targets sputtering system. The in-plane X-ray diffraction analysis clarified that there is anisotropic residual stress which is the origin of the high in-plane magnetic anisotropy. The directional crystalline alignment and inclination of crystallite growth were also observed. Such anisotropic crystalline structures may affect the anisotropic residual stress in the films. The B content of 5.6 at.% was appropriate to induce such anisotropic residual stress and $H_k$ of 410 Oe in this experiment. The film with B content of 6 at.% possessed large saturation magnetization of 22 kG and high $H_k$ of 500 Oe. The film exhibited high ferromagnetic resonance frequency of 9.2 GHz.

• Interaction and multiscale mechanics
• /
• v.3 no.3
• /
• pp.213-234
• /
• 2010

A multiscale method is presented for analysis of thin slab structures in which the microstructures can not be reduced to two-dimensional plane stress models and thus three dimensional treatment of microstructures is necessary. This method is based on the classical asymptotic expansion multiscale approach but with consideration of the special geometric characteristics of the slab structures. This is achieved via a special form of multiscale asymptotic expansion of displacement field. The expanded three dimensional displacement field only exhibits in-plane periodicity and the thickness dimension is in the global scale. Consequently by employing the multiscale asymptotic expansion approach the global macroscopic structural problem and the local microscopic unit cell problem are rationally set up. It is noted that the unit cell is subjected to the in-plane periodic boundary conditions as well as the traction free conditions on the out of plane surfaces of the unit cell. The variational formulation and finite element implementation of the unit cell problem are discussed in details. Thereafter the in-plane material response is systematically characterized via homogenization analysis of the proposed special unit cell problem for different microstructures and the reasoning of the present method is justified. Moreover the present multiscale analysis procedure is illustrated through a plane stress beam example.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.11a
• /
• pp.47-48
• /
• 2006

Carbon nanotubes (CNTs)-doped homogeneously aligned nematic liquid crystal (LC) cells driven by in-plane field were fabricated and their electro-optic characteristics were investigated. Effective cell retardation values in an absence of an electric field between doped and undoped LC were the same each other. In the presence of an electric field, however, measured effective cell retardation value was smaller in the CNT-doped cell than in the undoped cell so that the transmittance was slightly smaller in the CNT-doped cell than in the undoped cell. In addition, the CNT-doped cell exhibited slight increase in driving voltage and decrease in response time compared to the undoped cell. The CNT effects on electro-optic characteristics of the cell were discussed.

• Journal of Magnetics
• /
• v.20 no.1
• /
• pp.8-10
• /
• 2015

The magnetic anisotropy field plays an important role in spin-orbit-torque-induced magnetization dynamics with electric current injection. Here, we propose a magnetometric technique to measure the magnetic anisotropy field in nanostructured ferromagnetic thin films. This technique utilizes a magneto-optical Kerr effect microscope equipped with two-axis electromagnets. By measuring the out-of-plane hysteresis loops and then analyzing their saturated magnetization with respect to the in-plane magnetic field, the magnetic anisotropy field is uniquely quantified within the context of the Stoner-Wohlfarth theory. The present technique can be applied to small nanostructures, enabling in-situ determination of the magnetic anisotropy field of nanodevices.

• Computers and Concrete
• /
• v.14 no.3
• /
• pp.263-277
• /
• 2014

This study investigated four electric field configurations of two-dimensional accelerate lithium migration technique (ALMT), including line-to-line, plane-to-line, contour-to-line and plane-to-plane, and analyzed the ion migration behavior and efficiency. It was found that the free ion distribution diagram and voltage distribution diagram were similar, and ions migrated in the power line direction. The electrode modules were used for the mortar specimen with w/c ratio of 0.5. The effectively processed areas accounted for 14.1%, 39.0%, 49.4% and 51.4% of total area respectively on Day 28. Larger electrode area was more advantageous to ion migration. In addition, it was proved that the two-dimensional electric field could be divided into different equifield line active regions, and regarded as affected by one-dimensional electric field, and the ion migration results in various equifield line active regions were predicted by using the duration analysis method based on the theoretical model of ion migration obtained from one-dimensional test.

• Journal of the Korean Geophysical Society
• /
• v.2 no.4
• /
• pp.235-240
• /
• 1999

From the seismic network data of the Korea Institute of Geology, Mining & Materials during 1995-1996, we derived a composite fault-plane solution of the microearthquakes occurred in the Yangsan fault area. The composite fault-plane solution of nine events shows the orientation of fault 15 ± 3°in strike, 60 ± 8°in dip and 140°in rake or 128 ± 3°in strike, 56 ± 8°in dip and 37°in rake. The compressional axis of the stress field trends ENE to WSW, and this field suggests strike-slip motion with thrust component. The result is consistent with the 1996 Yeong-weol event and the stress field in and around the Korean Peninsula, previously reported.