• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.945-948
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• 2002

We studied electro-optical (EO) performances of a vertical-alignment (VA)-in plane switching (IPS) cell on a photopolymer surfaces. The VA-IPS cell, dark in voltage-off state, reveals bright uniformity in all directions due to the dual domainlike dierector configuration in the voltage-on state. For voltage-transmittance (V-T) measurement, the transmittance characteristics of the VA-IPS cell on the photopolymer surface was better than that of the VA-IPS cell on a polyimide(PI) surface.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.19-37
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• 1996

Scanning electron microscopy (SEM) has been applied to observe directly the {{{{ SQRT { 19} }}}}${\times}${{{{ SQRT { 19} }}}} and (1${\times}$1)HT reconstructions and the transition associated step bunching on the GaAs (111)B surfaces under As pressure. Close to the transition point, {{{{ SQRT { 19} }}}}${\times}${{{{ SQRT { 19} }}}}an d (1${\times}$1)HT reconstructions are observed in dark and bright domains by SEM and determined by micro-probe reflection high-energy electron diffraction (${\mu}$-RHEED). The reconstruction diagram shows hyster-esis. The stepped surface morphology during the reconstruction transition was unstable. Heavy step bunching with rough macrostep edges was observed.

• The Journal of Natural Sciences
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• v.19 no.1
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• pp.27-35
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• 2008

The importance of microbial activity in the alteration and deterioration of stone and concrete walls has been frequently neglected. Organisms present on stone monuments can include photolithoautotrophs, such as algae, cyanobacteria, mosses, and higher plants. Because of their ability to survive repeated drying and rehydration cycles and high UV levels, the cyanobacteria are particularly important on exposed surfaces. The cyanobactria distributed on the surface of the stone cultural heritages in Gwanschoksa, Nonsan city were investigated. Chlorococcus sp. Aanabaena sp. Gloeocapsa sp Lyngbya sp. Stigomena sp. Synechocystis sp were identified. Haplaosiphon fontinalis and Stigonema turfaceum, which were not recoded is Korea, were also identified. Cells often have thick pigmented sheath in dry, sun-exposed environment and shorter filament, which can be different than that in aquatic systems. Special attention should be paid to production of an adequate DNA database in order to accelerate the rate at which information on the species present in biofilms become available.

• Journal of Veterinary Clinics
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• v.33 no.5
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• pp.313-315
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• 2016

An aged (14 years old) female snow leopard exhibited renal calculi and pyelonephritis at necropsy. The animal experienced appetite loss, mild diarrhea, polydipsia, and difficulty breathing, and was curled up and staggering on its hind legs 2 days before death. Large calculi were found obstructing both sides of the renal pelvis. The left-side calculus was larger than that of the right side. These calculi had rough surfaces and were $15{\times}21mm$ and $9{\times}14mm$, respectively. The bladder was filled with dark, cloudy urine. Multiple ulcerous lesions were found in the inner layer of the bladder. Enterococcus faecalis and Proteus mirabili were identified via microbiological examination of the urine. Under microscopic examination, urine struvites were observed in the pyuria sediment in the bladder. To our knowledge, this is the first documented case of nephrolithiasis in a captive snow leopard.

• The Korean Journal of Mycology
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• v.50 no.1
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• pp.41-46
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• 2022

Gastrodia elata infected with root rot disease was collected from cultivated G. elata fields in Gimcheon, Korea, in 2018. G. elata tuber surfaces exhibited root rot disease symptoms of dark-grey lesions and white fungal mycelial growth. The fungus was isolated from symptomatic tubers and cultured. Based on morphological characteristics and molecular analysis of the internal transcribed spacer region of ribosomal DNA and translation elongation factor 1-alpha, the isolated fungus was Fusarium oxysporum. This is the first report of root rot caused by F. oxysporum on G. elata tubers in Korea.

• Korean Journal of Plant Tissue Culture
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• v.27 no.1
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• pp.19-23
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• 2000

The experiment was carried out to investigate the influence of light condition and polarity of explant on adventitious shoot formation from cotyledon of apple in vitro The treatment of light culture after 10days dark treatment showed effective result than other treatments on the rate of adventitious shoot formation on light intensity treatments and also the treatment of blue light treatment after 4days dark treatment showed more effective result than other treatments in light quality treatments. The polarity of explant influence on adventitious shoot formation. Adventitious multiple shoot formation occured at the proximal end of an excised cotyledon. In other words. shoot organogenesis occured at the proximal cut surfaces of both proximal and distal explants rather than at the distal cut surface of proximal explants.

• Journal of The Korean Astronomical Society
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• v.56 no.2
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• pp.293-299
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• 2023

The Wide-Angle Polarimetric Camera (PolCam) is installed on the Korea's lunar orbiter, Danuri, which launched on August 5, 2022. The mission objectives of PolCam are to construct photometric maps at a wavelength of 336 nm and polarization maps at 461 and 748 nm, with a phase angle range of 0°-135° and a spatial resolution of less than 100 m. PolCam is an imager using the push-broom method and has two cameras, Cam 1 and Cam 2, with a viewing angle of 45° to the right and left of the spacecraft's direction of orbit. We conducted performance tests in a laboratory setting before installing PolCam's flight model on the spacecraft. We analyzed the CCD's dark current, flat-field frame, spot size, and light flux. The dark current was obtained during thermal / vacuum test with various temperatures and the flat-field frame data was also obtained with an integrating sphere and tungsten light bulb. We describe the calibration method and results in this study.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.1
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• pp.107-114
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• 2011

In this study, a correlation between the roughness of nanoscale lapping surface and its laser scattering pattern has been identified experimentally. The characteristics of laser scattering on a reflected surface are investigated, and a laser scattering mechanism is newly designed by adopting the dark-field method. Laser scattering patterns resulting from nanoscale lapping shape are in the shape of crossed irregular lattice. In addition, optimum laser scattering images are obtained by the design of experiment, and the roughness of nanoscale lapping surface is estimated using regression analysis certain useful features of the laser scattering patterns. The results of fifty experiments on three types of nanoscale lapping surfaces show that the roughness of nanoscale lapping surfaces can be accurately estimated by the proposed mathematical modeling method.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.3
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• pp.171-178
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• 2008

Metal filter elements were newly introduced to the high temperature filter(HTF) system in the low- and intermediate-level radioactive waste vitrification plant. In order to evaluate the performance of various metal materials as filter media, elements made of AISI 316L, AISI 904L, and Inconel 600 were included to the test set of filter elements. At the visual inspection to the elements performed after completion of each test, a few dark spots were observed on the surface of some elements. Especially they were found much more at the AISI 316L elements than others. To check the dark spots are the corrosion phenomena or not, two kinds of analyses were performed to the tested filter elements. Firstly, the surfaces or the cross sections of filter specimens cut out from both normal area and dark spot area of elements were analyzed by SEM/EDS. The results showed that the dark spots were not evidences of corrosion but the deposition of sodium, sulfur and silica compounds volatilized from waste or molten glass. Secondly, the ring tensile strength were analyzed for the ring-shape filter specimens cut out from each kind of element. The result obtained from the strength tested showed no evidence of corrosion as well. Conclusionally, depending on the two kinds of analysis, no evidences of corrosion were found at the tested metal filter elements. But the dark spots formed on the surface could reduce the effective filtering area and increase the overall pressure drop of HTF system. Thus, continuous heating inside filter housing up to dew point will be required normally. And a few long-period test should be followed for the exact evaluation of corrosion of the metal filter elements.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.109.1-109.1
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• 2015

Understanding the reaction mechanisms and structures underlying the adsorption of biomolecules on semiconductors is important for functionalizing semiconductor surfaces for various bioapplications. Herein, we describe the characteristic behavior of a primary nucleobase adsorbed on the semiconductor Ge(100). The adsorption configuration of guanine, a primary nucleobase found in DNA and RNA, on the semiconductor Ge(100) at an atomic level was investigated using scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. When adsorbed on Ge(100) at room temperature, guanine appears dark in STM images, indicating that the adsorption of guanine on Ge(100) occurs through N-H dissociation. In addition, DFT calculations revealed that "N(1)-H dissociation through an O dative bonded structure" is the most favorable adsorption configuration of all the possible ones. We anticipate that the characterization of guanine adsorbed on Ge(100) will contribute to the development of semiconductor-based biodevices.