• Textile Coloration and Finishing
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• v.13 no.4
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• pp.227-233
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• 2001

Wool fabrics were pre-treated with corona prior to treating with enzyme for shrinkage resistance. Commercial protease and cellulase were used for degradation of wool and the treatment conditions such as enzyme amount, treating time, and assistant chemicals. Friction coefficient and zeta-potential were measured to certificate an effect of treatment condition on the handle of wool fabric. Corona pretreatment make the wool fabric soft, which result in the decrease of friction coefficient and zeta-potential. Scale removal of wool surface was observed by scanning electron microscope. Amino acid analysis shows the effectiveness of enzyme, and corona pretreatment does not cause severe internal damage.

• Journal of the Korean institute of surface engineering
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• v.32 no.3
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• pp.423-427
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• 1999

Electroplating of 80%Ni permalloy thin plate for magnetic core materials. was studied The convected flow of electrolyte was used for stirring methode. The current density could be increased up to 250mA/$\textrm{cm}^2$ by flow cell. The composition of electroplated layer with vespect to current density and flow rate was investigated and experimental equation to predict the composition was made. How cell yielded more uniform thickness distribution than paddle cell did. The composition distribution was also studied. The thickness was the most important factor to the permeability. The permeability of 5$\mu\textrm{m}$plated permalloy was over 2000 at 1 MHz.

• Journal of the Korean institute of surface engineering
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• v.16 no.3
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• pp.98-107
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• 1983

A study on the improvement of wear resistance of brasses by electroplating and diffusion treatment of tin was carried out. The optimum condition of the treatment obtained was as follows. Plating thickness of tin : 5 - 9 $\mu\textrm{m}$ Condition of diffusion treatment : atmosphere ; fused nitrate bath (KNO3 + NaNO3) temperature and time ; 1st step 320$^{\circ}C$, 60min. and 450$^{\circ}C$, 30min. During the diffusion treatment, internetallic compounds of Cu-Sn were formed and these compounds were identified as η, $\varepsilon$ and $\delta$ phase from the outer tin layer. It was considered that the improvement of wear resistance of brasses by the treatment is because of the formation of intemetallic compounds particalarly $\varepsilon$phase which is very hard, between soft tin layer brass.

• Journal of the Korean institute of surface engineering
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• v.51 no.4
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• pp.202-206
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• 2018

Permalloy($Ni_{80}-Fe_{20}$) which is known for its soft magnetic properties is a well-known material that has been studied intensively. Permalloy nanoflakes were fabricated with the combination of electrodeposition and sonication process. Ultrasonic power was applied to the deposited alloy which produced nanoflakes in forms of sheet. High internal stress created cracks which helped the peeling of permalloy into nanosheets. Because of shape anisotropy, flakes could be aligned by magnetic field. The magnetic properties of the nanosheets were observed, and the variation of magnetic properties with the alignment of flake was also investigated.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.226.2-226.2
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• 2003

.The healing of a bone defect is complex, and involves a wide range of cellular, molecular, physiological, and biological processes. The main effect of bone substitute is to promote wound healing by induce cell proliferation. Bone defect sites usually are localized below the original bone surface; therefore, space production and maintenance between the membrane and the original bone surface is essential. As a result, membranes must have proper mechanical strength to prevent the collapse of the soft tissue and maintain wound space that permits membranes of poly (L-lactide) (PLLA) were fabricated to provide and maintain sufficient space for bone growth. (omitted)

• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.198-201
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• 2012

The electrolytes in thermal batteries are nonconductive solids at ambient temperature, which prevent the self-discharge and corrosion. To meet severe environmental requirements and guarantee acceptable handling yields, all the pellets in cells should have adequate strength, especially for the cathodes due to their poor binding properties among FeS2 particles. By modifying the surface microstructure of FeS2 through molten-salt heat treatment, the inter-particle binding strength is greatly increased, resulting in the enhanced pellet strength and yield. The addition of Li2O also promoted the soft salt coating coverage of hard FeS2 particles, which can be explained by the enhanced wettability of the molten salt.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.8
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• pp.958-968
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• 2003

The purpose of this study was to clarify the different mechanical properties of fabrics among the theme groups classified by fashion fabric trend. This study can be useful for fabric marketers and planners to design new products. In order to carry out this study, the fabric samples of representative theme for‘2002/03 F/W fashion fabric trend were collected from a fashion company and were measured to analyze the mechanical properties, hand value(H.V) and total hand value(T.H.V) by KES-FB System. The results were as follows. 1. The theme-A of‘Luxury, Elegance’was consisted of wool, rayon and PET and had a lower B, 2HB of bending properties and a lower G and 2HG5 of shear properties. The theme-B of‘Technical, Functional’was consisted of synthetic fibers such as PET, PA, PU and elastic fiber and had a higher MIU and a lower MMD, SMD of surface properties. The theme-C of‘Vintage, Aged’was consisted of mostly cotton and had the highest B and 2HB. The theme-D of‘Fancy, Airy’was consisted of mostly woolen wool, polyacryl and polyamide and had a high MMD and SMD of surface properties and a high LC and RC of compression properties. 2. As the results of analyzing H.V and T.H.V through KES-FB system, the theme-A showed a higher Smoothness and lower Stiffness. The theme-B had a lower Smoothness, Fullness, Soft feeling and T.H.V and the theme-C had the highest Stiffness. The theme-D showed the highest Fullness and Soft Feeling but the lowest Stiffness.

• Journal of the Korea Computer Graphics Society
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• v.17 no.2
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• pp.11-16
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• 2011

In computer graphics, shadows play a very important role as a hint of inter-object distance as well as themselves in terms of realism. To represent shadows, some traditional methods such as shadow mapping and shadow volume have been frequently used for the purpose. However, the rendering results are not natural since they assume the point light. On the contrary, an area light can render soft-shadows, but its computation is too burdensome due to integral over the whole light source surface. Many alternatives have been introduced, back-projection of occluder onto the light source to get visibility of light or filtering of shadow boundary by calculating size of penumbra. But they also have problems of light bleeding or ringing effects because of low order approximation, or low performance. In this paper, we describe a method to improve those problems using shadow atlas.

• Journal of Advanced Navigation Technology
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• v.12 no.2
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• pp.139-145
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• 2008

There has been lots of studies on communication systems using millimeter wave recently in many countries, specially in newly assigned 57GHz ~ 64GHz ISM band. Among those studies, IEEE 802.15.3c standard proposes OFDM (Orthogonal Frequency Division Multiplexing) systems for high data rate transmission support. But OFDM method has the PAPR (peak-to-Average Power Radio) problem The PAPR problem is to decline the performance of the transmission system due to signals distorted severely when passing through nonlinear components such as ADC/DAC and power amplifiers. In order to solve the problem of P APR, this paper suggests SSC (Sine Soft Clipping) and analyzes the PAPR, CCDF, PSD, BER by applying SAW(Surface Acoustic Wave) filter and power amplifiers to IEEE 802.15.3.c OFDM WPAN systems.

• Journal of the Korean Magnetics Society
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• v.19 no.6
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• pp.191-196
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• 2009

Magnetic bias phenomena of field-annealed CoFeSiB amorphous ribbons showing asymmetric giant magnetoimpedance was investigated by MOKE method. The specimens removed the crystalline layer at one surface side by chemical etching were prepared and measured magnetization curves by MOKE to investigate the effect of the crystalline layer on magnetization of inner soft amorphous phase. We observed the shift of hysteresis loop, and concluded that the crystalline layer exerts bias field effect on inner soft amorphous phase and the direction of bias filed is opposite to the magnetization direction of surface crystalline layer.