• Korean Journal of Materials Research
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• v.10 no.8
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• pp.575-580
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• 2000

Diamond thin films were deposited on $Si_3N_4$, SiC, TiC and $Al_2O_3$, substrates by the CVD method using Ta(TaC)Filament, and the appearance of the diamond films and their adhesion properties were examined by SEM, optical microscopy, indentation test and compression topple test. Diamond films were deposited at lower $CH_4$ concentration than 5%$CH_4$ for all kinds of the substrate material, but graphitic(amorphous)carbon was observed at 10%$CH_4$. The diamond film of about $12\mu\textrm{m}$ thickness on WC substrate partly peeled off, but the film on $Si_3N_4$ substrate held good adhesion. The indentation test showed that roughly ground surface was very effective for adhesion of diamond films to substrate. The topple test revealed that film thickness was an important factor governing the adhesion of the diamond film.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.227-232
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• 1998

Diamond crystallization and discontinuous deposit phenomena depend on the process of hydrocarbon deposition, nucleation and growth. Then, it is investigated the concentration of methane, flow rate, structure and the growth process of $CH_4-H_2$ system in hot filament assisted C.V.D. There is a limited value of temperature, pressure, flow rate and the mole fraction of methane-hydrogen gas. Diamond nucleation occurs on substrate selectively and surface diffusion of species on the substrate plays an important role in the early stages of nucleation and growth.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.11
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• pp.1481-1487
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• 2002

The thin SiC filament technique has been employed to identify the possibility of measuring flame temperature, and especially unstable near-extinction flame temperature in an oxidizer deficient ambience, by comparing the relative visible (non-IR) luminosities of SiC filaments with thermocouple measured temperature in co-flowing, laminar propane/air diffusion flames. The results show good agreement between the digitized relative visible luminosity profiles of the SiC filaments and temperature profiles measured using a thermocouple at temperatures above $700^{\circ}C$, although, a non-linear calibration is probably required far the whole temperature range. The highest radial peak temperature exists near to the nozzle exit. and the centerline temperatures were virtually unchanged with increasing flame height in an oxidizer deficient near-extinction flame.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.210-210
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• 2000

Vertically well aligned multi-wall carbon nanotubes (CNT) were grown on nickel coated glass substrates by plasma enhanced hot filament chemical vapor deposition at low temperatures below 600$^{\circ}C$. Acetylene and ammonia gas were used as the carbon source and a catalyst. Effects of growth parameters such as pre-treatment of substrate, plasma intensity, filament current, imput gas flow rate, gas composition, substrate temperature and different substrates on the growth characteristics of CNT were systematically investigated. Figure 1 shows SEM image of CNT grown on Ni coated glass substrate. Diameter of nanotube was 30 to 100nm depending on the growth condition. The diameter of CNT decreased and density of CNT increased as NH3 etching time etching time increased. Plasma intensity was found to be the most critical parameter to determine the growth of CNT. CNT was not grown at the plasma intensity lower than 500V. Growth of CNT without filament current was observed. Raman spectroscopy showed the C-C tangential stretching mode at 1592 cm1 as well as D line at 1366 cm-1. From the microanalysis using HRTEM, nickel cap was observed on the top of the grown CNT and very thin carbon amorphous layer of 5nm was found on the nickel cap. Current-voltage characteristics using STM showed about 34nA of current at the applied voltage of 1 volt. Electron emission from the vertically well aligned CNT was obtained using phosphor anode with onset electric field of 1.5C/um.

• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.1
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• pp.35-50
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• 2007

We performed the subjective sensibility evaluation on knitted fabrics by the following procedures: setting acrylic fabrics used for S/S among fabrics as basis, five kinds of blended spun yarns and four kinds of twisted filament yarns made by different twisting methods then, we did questionnaire survey targeting sixty females in the expert groups. Utilizing SPSS 12.0, correlation, ANOVA, Duncan, and Multidimensional Standard way were analyzed. The results are as following. First, the result of evaluating on preferred knits followed by the analysis of the sense factor, in the 'drape sense', the acrylic/rayon blended knit was preferred as the most flexible, pliable, and elastic knit; in weight/bulk factor, the acrylic filament knit the most twisted was preferred as the least bulk, thin, cool and transparent knit; in 'surface depression sense' factor, A(F)W acrylic/wool blended knit was preferred as the most haggard, straight, dry knit. Second, the result of evaluating on preferred knits followed by the analysis of the sensibility factor, in the 'neatness' the acrylic filament hit was preferred as the most clean, neat and delightful knit; in the 'comfortableness', the acrylic/wool blended knit was preferred as the most natural, stable, and comfortable knit. Third, according to the result of evaluating on preferred knits as the spring and summer, generally the acrylic filament twisted yarn knits were more preferred than the acrylic blended yarns. However the preference on the kinds of the acrylic twisted filament yarn showed that there is a little difference on the acrylic blended yarn knit.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.249-254
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• 2008

The present study was undertaken to determine whether hypoxia influences on the agonist-induced vascular smooth muscle contraction and, if so, to investigate the related mechanism. The measurement of isometric contractions using a computerized data acquisition system was combined with molecular experiments. Hypoxia significantly inhibited fluoride-induced contraction regardless of endothelial function, but there was no relaxation on thromboxane $A_2$ mimetic U-46619-induced contraction suggesting that other pathway such as $Ca^{2+}$ entry or thin filament regulation was not affected. In addition, hypoxia significantly decreased fluoride-induced increase of phospho-myosin-targeting subunit of myosin light chain phosphatase (pMYPT1). Interestingly, hypoxia didn't inhibit significantly phenylephrine-induced contraction suggesting that myosin light chain kinase (MLCK) activity or thin filament regulation is less important on the hypoxia-induced vasorelaxation in the denuded muscle than Rho-kinase activity. In conclusion, this study provides the evidence and possible related mechanism concerning the vasodilation effect of hypoxia on the agonist-specific contraction in rat aortic rings regardless of endothelial function.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.1034-1037
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• 2003

Microcrystalline silicon(c-Si:H) thin-film solar cells are prepared with intrinsic Si-layer by hot wire CVD. The operating parameters of solar cells are strongly affected by the filament temperature ($T_f$) during intrinsic layer. Jsc and efficiency abruptly decreases with elevated $T_f$ to $1400^{\circ}C$. This deterioration of solar cell parameters are resulted from increase of crystalline volume fraction and corresponding defect density at high $T_f$. The heater temperature ($T_h$) are also critical parameter that controls device operations. Solar cells prepared at low $T_h$ ($<200^{\circ}C$) shows a similar operating properties with devices prepared at high $T_f$, i.e. low Jsc, Voc and efficiency. The origins for this result, however, are different with that of inferior device performances at high $T_f$. In addition the phase transition of the silicon films occurs at different silane concentration (SC) by varying filament temperature, by which highest efficiency with SC varies with $T_f$.

• Journal of the Korean Society of Costume
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• v.61 no.2
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• pp.88-101
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• 2011

This study emphasizes on the characteristics of the excavated fabrics from the tomb of Kimwhoak in the late 16th and early 17th centuries. All of 118 kinds of fabrics are used in excavated costume from the tomb of Kimwhoak. Classified by its materials, it is divided into small groups as follows: 63 pieces of spun silk tabby(53.6%), 14 of spun yarn silk(11.9%), 13 of thin filament silk tabby(11.0%), 8 of thin silk tabby(6.8%), 4 of satin without pattern(3.4%), 3 of filament silk tabby(2.5%), 3 of twill without pattern(2.5%), 2 of satin damask(1.7%), 2 of mixture fabric with silk and cotton(1.7%), and 2 of ramie fabric(1.7%), 1 of simple gauze without pattern(0.8%), 1 of damask with supplementary gold thread(0.8), 1 of cotton(0.8%), 1 of etc(0.8%). Classified by ways of weaving: 106 pieces of plain weave(89%), 6 of satin weave(5%), 3 of twill weave (3%), 1 of gauze weave(1%), 1 of compound weave(1%) and etc(1%). In point of patterns, the most of textiles are without pattern, there are only two of them are patterned textile. such as lotus patterns with vine, peony patterns with vine. Their patterns are very similar to those of other tombs in the same age.

• Journal of the Korean Home Economics Association
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• v.45 no.2
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• pp.51-62
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• 2007

This study explicates some properties of the fabrics used in the 16th century by examining and analyzing the 90 pieces of fabric excavated from the graves of Mr. Ryu of Jinju and his wife Mrs. Park of Euiin. The fabrics were classified into silk tabby(紬), thin silk tabby, satin damask(段), complex gauze(羅), mixture fabric with silk and cotton(絲棉交織), cotton(棉布) etc. Compared to other contemporary fabrics excavated previously, the fabrics unearthed from the couple's graves presented very naive feelings. Patterned satin damask occupied a small portion. In the case of plain fabric, little filament silk tabby(絹) or thin filament silk tabby(細紬) was unearthed. Important data on the history of Korean costumes are provided by the noteworthy, first-ever excavation of a small cap made of complex gauze(羅) and the tiger-leopard embroidered patches called hyoongbae(胸背), which were worn on the front and back of official robes made of tabby with supplementary gold thread(金線). Only 3 pattern types could be clearly identified in form, cloud pattern, lotus and vine pattern(蓮花蔓草), and small flower and treasures pattern(七寶細花). These three patterns are very similar to those of other 16th century fabrics unearthed previously in terms of the form and arrangement of patterns.

• Proceedings of the KIEE Conference
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• 1997.07e
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• pp.1752-1754
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• 1997

The Kaufman type ion beam source with focusing lens was prepared to measure $\gamma$-coefficient of MgO thin film. Initial discharge of the system was started with the discharge voltage of 25V, the cathode filament current of 5.5A at the constant magnetic field of 150G. The system shows the maximum ion current density of $120{\mu}A/cm^2$, energy dispersion of 200eV and beam divergence of $30^{\circ}$ under the condition of Ar gas pressure $2.5{\times}10^{-4}Torr$, the beam voltage of 500V, the discharge voltage of 90V, the accelerator voltage of -200V and the cathode filament current of 6.1A. When the focusing lens was installed onto the ion beam source, the spreadness diameter of ion beam was about 10mm.