• Proceedings of the Korean Vacuum Society Conference
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• 2003.08a
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• pp.218-218
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• 2003

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.367-367
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• 2011

CIGS solar cell with copper, indium, gallium and selenium is a second generation solar cells for the lowering of the manufacturing cost. The relative ratio of the four elements is one of the most important measurement issues because the photovoltaic property of CIGS solar cell depends on the crystalline structure of the CIGS layer. However, there is no useful analysis method for the composition of the CIGS layer. Recently, AES depth profiling analysis of CIGS films has been studied with a reference material certified by inductively coupled plasma optical emission spectroscopy. However, there are some problems in AES depth profiling analysis of CIGS films. In this study, the in-depth profiling analysis was investigated by secondary ion mass spectrometry (SIMS) depth profiling analysis. We will present the compositional depth profiling of CIGS films by SIMS and its applications for the development of CIGS solar cells with high efficiency.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.3
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• pp.15-26
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• 1997

In this study, the theoretical investigation of the electrically heated catalyst(EHC) for vehicle application has been carried out using the thermal equivalence of EHC system and the data of vehicle tests to meet ultra low emission vehicle(ULEV) standard. To improve the efficiency of EHC system, it is necessary to understand relation between the power, the operating time and the conversion efficiency of EHC system. The relation was found with thermal equivalence of EHC system which considers the power supply to EHC, heat loss, chemical exothermic energy generated by oxidation reaction and net energy coming in via the exhaust gas. From this relation, the limits of needful power and operating time to meet the ULEV standard can be suggested, when the conversion efficiency of catalyst was known.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.357-360
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• 1996

MgO protection layer in ac PDP(plasma display panel) prevents the dielectric layer from ion bombarding in discharge plasma. The MgO layer also has the additional important role in lowering the firing voltage due to a large secondary electron emission coefficient. Until now, the MgO protection layer is mainly prepared by E-beam evaporation. In this study, MgO protection layer is prepared on dielectric layer of ac PDP cell by reactive R.F magnetron sputtering with Mg target under various conditions of oxygen partial pressure. Discharge characteristics of PDP is also studied as a parameter of MgO preparation conditions. The sputtered MgO shows the better discharge characteristics compared with MgO deposited by E-beam evaporator.

• Proceedings of the KIEE Conference
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• 1997.07e
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• pp.1834-1836
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• 1997

In this study, we simulated the developing process of two-dimensional corona discharge using the fluid method in 760 torr. It was assumed that the transport coefficients of nitrogen gas were only the function of local electric field. Discharge mechanisms considered were a Townsend first ionization and a secondary electron emission. We obtained spatio-temporal distribution of electron and ion by calculating continuity equation using FCT algorithm and calculated an electric field distribution considering a space charge.

• Korean Journal of Cleft Lip And Palate
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• v.8 no.2
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• pp.95-105
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• 2005

Cleft lip and palate is a congenital deformity which needs a professional and consistent management from the birth and along with the physical growth of patients. The patients with cleft lip and palate can have general speech problems with resonance disorders, voice disorders and articulation disorders after the successful primary surgical management and the physical growth. Speech problems of Cleft lip and palate are characterized hypernasality, nasal air emission, increased nasal air flow, and aberrant speech marks which decrease intelligibility. These speech problems of cleft lip and palate can be treated with the secondary surgical procedure, the application of temporary prosthesis and the effective and well-timed speech therapy. The speech and language problems of cleft lip and palate, the general procedures and schedules of the speech assessment and therapy based on the multidisciplinary approach are introduced for the patients with cleft lip and palate, their family and the other members of the cleft palate treatment team.

• Macromolecular Research
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• v.16 no.7
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• pp.604-608
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• 2008

Color dye-doped silk fibroin nanoparticles were successfully fabricated using a microemulsion method. An aqueous silk fibroin solution was prepared by dissolving cocoons (Bombyx mori) in a concentrated lithium bromide solution followed by dialysis. A color dye solution was also mixed with the aqueous silk fibroin solution. The surfactants used for the microemulsion were then removed by methanol and ethanol, yielding color dye-doped silk fibroin nanoparticles, approximately 167 nm in diameter. The secondary structure of the nanoparticles showed a $\beta$-sheet conformation, as characterized by Fourier transform infrared spectroscopy. The morphology of the nanoparticles was determined by field emission scanning electron microscopy, transmission electron microscopy and atomic force microscopy, and their size and size distribution were measured by dynamic light scattering. The color dye-doped silk fibroin nanoparticles were examined by confocal laser scanning microscopy.

• Animal cells and systems
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• v.10 no.4
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• pp.183-189
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• 2006

The fine structural characteristics of the antennal sensory organs of a female millipede, Orthomorphella pekuensis, were observed with field emission scanning electron microscopy. On the surface of the antenna, four basic types of sensory receptor with the function of either mechanical or olfactory reception are identified in this female millipede. Of these, chaetiform sensilla (CS) and trichoid sensilla (TS) are related to mechanical reception, and four large apical cone sensilla (AS) and three subtypes of basiconic sensilla ($BS_1,\;BS_2,\;BS_3$) are likely to function in olfactory reception, as these receptors have porous structure commonly. Although this millipede also possess a number of primary or secondary sexual characters to improve the efficiency of reproduction, we could not observe their prominent sexually dimorphic characters in the antennal sensilla with the exception of minor structural and numerical differences.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.135.1-135
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• 2003

To elucidate the effect of gamma-irradiation on the molecular properties of hemoglobin, the secondary, tertiary structure, and the molecular weight size of the protein were examined after irradiation at 0.5, 1, 5, and 10 kGy. Gamma-irradiation of hemoglobin solutions caused the disruption of the ordered structure of the protein molecules, as well as degradation, cross-linking, and aggregation of the polypeptide chains. A SDS-PAGE study indicated that irradiation caused initial fragmentation of the proteins and subsequent aggregation due to cross-linking of the protein molecules. The effect of irradiation on the protein was more significant at lower protein concentrations. Ascorbic acid decreased the degradation and aggregation of proteins by scavenging oxygen radicals that were produced by irradiation. A circular dichroism study showed that irradiation decreased the helical content of hemoglobin with a concurrent increase of the aperiodic structure content. Fluorescence spectroscopy indicated that irradiation decreased the emission intensity that was excited at 280 nm.

• Proceedings of the Korean Vacuum Society Conference
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• 2001.07a
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• pp.174-174
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• 2001