Ion-beam irradiation(IB) on HfO2 surface induced high-performance liquidcrystal(LC) driving at a 1-V threshold with vertical alignment of liquid crystals(LC). The high-k materials Atomic layer deposition was used to obtain LC orientation on ultra thin and high-quality films of HfO2 layers. To analyze surface morphological transition of HfO2 which can act as physic alignment effect of LC, atomic force micro scopy images are employed with various IB intensities. The contact angle was measured to elucidate the mechanism of vertical alignment of LC on HfO2 with IB irradiation. Contact angle measurements show the surface energy changes via IB intensity increasing.

I investigated the homogeneous liquid crystal alignment using parallel patterning on nickel oxide thin film. Nickel oxide thin film was prepared by sol-gel process, which is and cost effective method to form oxide thin film. Since the sol-gel process is solution driven method, the patterning on nickel oxide can be achieved by imprinting lithography. Nickel oxide with parallel pattern was used for liquid crystal alignment layer, which can be a alternative to conventional rubbing process to aligning a liquid crystal molecules. As a result, a high transmittance of 83.9% was confirmed for the NiO film, and a stable horizontal orientation pretilt angle of 0.2° occurred in the imprinted NiO film. These results were judged to be a positive level that can be commercialized in the horizontal alignment type liquid crystal display that is currently used universally. Anisotropic characteristics of nickel oxide induced by a parallel pattern leads to the alignment of liquid crystals.

In this study, We studied design method to reduce scattering reflection by adding a three - dimensional structure to light guide plate of LED backlight widely used in small and portable devices. In order to improve the efficiency of the light-incident part, a three-dimensional structure is used in which a repetitive structure of a prism shape and a semi-cylindrical shape is repeatedly added to the light-entering face in light-guide plate. As a result of the study, it was found that uniform luminance values were obtained in the light-incident portion and the backlight when a repetitive pattern of a semi-cylindrical shape was added as compared with a case in which a prism shape was added. Particularly, when a rectangular lens with a semi-cylindrical shape is added, the average value of the total luminance is increased by about 15% from 7278 lm to 8324 lm as compared with a general light guide plate.

In this study, the ion beam irradiation method on organic (polyamic acid and epoxy resin compound) overcoat layer was investigated. The use of ion beam on overcoat organic layer has the potential to replace conventional rubbing process. The traditional alignment layer is made by coating process and 2 times heat treatment on polyamic acid liquid. It requires many times and process steps. However, it is very economic and convenient process substitute polyimide alignment layer for organic overcoat. In order to characterize the LC alignment the polarized microscope image and pretilt angle measurement were investigated. The good LC aligning capabilities treated on the organic overcoat thin film surfaces with ion beam exposure of 45° at above ion beam energy density of 1200 eV were achieved.

Homogeneous liquid crystal (LC) alignment on hafnium strontium oxide (HfSrO) films prepared by sol-gel process via ion-beam (IB) bombardment was investigated. Uniform LC alignment was achieved on the IB-irradiated HfSrO films at IB intensity of 1.8 keV. We confirmed the effect of surface morphology on LC alignment using field-emission scanning electron microscope (FE-SEM). In addition, we observed electro-optical characteristics of the twisted-nematic (TN)-LC cells based on HfSrO films to verify the possibility of LC display (LCD) application.

Nematic liquid crystal (NLC) alignment effects on SiOF layers via ion-beam(IB) irradiation for four types of incident energy were successfully studied. The effect of fluorine addition on silicon oxide film properties as a function of SiOF₄/O₂gas flow ration was investigated. The SiOF thin film exhibits good chemical and the thermal stability of the SiOF thin film were sustained as function of the NLC alignment until 200℃. Also, the response-time characteristics of aligned LCD based on SiOF film were studied.

Technical developments of electric vehicles have been progressed very actively. Especially there are great technical achievements of battery for the electric vehicles to store energy from the outside source. Also there are numerous efforts for improvement charging infrastructure and charging system of the battery. And that is supporting this technology. For example On-Board Charger (OBC) is a battery charging system attached to the vehicle to operate the car. On-Board Charger is designed in manner of consideration such subjects: control via communication with other vehicle’s controller, improve the reliability as the security part, decrease of the life span of the battery due to temperature change during charging and discharging process, high cost of using parts for the high current rating and limitation of increasing the battery capacity. In this paper, there will be a deep discussion of designing and implementing the On-Board Charger to attach to the vehicles, which has superior cooling quality by effective radiant heat design and vibration and shock resistant design

These studies were carried out to improve the reproductive efficiency through embryos transfer of Hanwoo IVM/IVF embryos. Following routine IVM/IVF procedure, Oocytes and zygotes were cultured for 40 to 44 h in CR1aa medium with BSA. Then 2 to 8-cell embryos were removed the cumulus cell and were cultured in CR1aa medium containing 10% fetal bovine serum and 2.5 mM taurine in 5% O2 and 5% CO2 at 38.5℃. The fresh and frozen thawed embryos of the morulae and blastocysts cultured for 6 to 9 days in vitro were transferred into recipients. The pregnancy rates of the blastocyst produced for 6, 7, 8, and 9 days in in vitro culture were 41.9, 48.6, 57.9 and 47.4%, respectively. In the developmental stage, pregnancy rates of early blastocysts (41.7%), blastocysts (57.6%) and expanded blastocysts (50.0%) were higher than that of morulae stage (00.0%). Fresh and frozen embryos on the pregnancy rates were 48.9 and 50.0%, respectively. These results indicate that the pregnancy rate after transfer were affected on embryonic stage of in vitro embryos and in vitro culture periods.