• The Journal of Internal Korean Medicine
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• v.35 no.2
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• pp.157-174
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• 2014

Objectives : The aims of this study were to evaluate the diagnostic values of tongue coating thickness and sterno-costal angle as the quantitative diagnostic indicators in functional dyspepsia. Methods : We surveyed 60 functional dyspepsia patients recruited by the clinical trial, 'Clinical Trial for Evaluation on Availability of tongue diagnosis system (CTS-1000) : a Pilot study'. The patients were classified into three groups according to Rome III criteria for functional dyspepsia, and categorized into five groups according to Instrument of pattern identification for functional dyspepsia. Nepean dyspepsia index-Korean version (NDI-K) score, tongue coating thickness (percentage of tongue coating by tongue diagnosis system (CTS-1000), and weight of tongue coating by microbalance), sterno-costal angle, duration of illness and body mass index (BMI) were investigated. Results : Among the 5 types by instrument of pattern identification for functional dyspepsia, a significant difference of percentage of tongue coating was found. Percentage of tongue coating and weight of tongue coating showed significant correlation with total NDI-K score. Sterno-costal angle showed strong positive correlation with BMI and also showed significant difference between the non-overweight (BMI<23, n=32) and overweight ($BMI{\geq}23$, n=28) groups. Conclusions : Tongue coating thickness showed its potential as a new quantitative diagnostic indicator of functional dyspepsia. Further studies on the sterno-costal angle are anticipated to evaluate its potential as a new quantitative diagnostic indicator.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.66 no.2
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• pp.94-97
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• 2017

A method of improving the anti-fouling characteristics of porcelain insulators was proposed in this study. Functional coating was performed as a method of reducing the surface contamination of the porcelain insulators. The functional coating was applied on a ceramic substrate, which has the same material as the porcelain insulators. After coating the ceramic substrate 2, 3, 4, and 5 times alternately in the horizontal and vertical directions, the surface characteristics according to the thickness of the coating film were analyzed. The optimal process was selected to coat the surfaces of the post insulators and long rod insulators, which are the representative porcelain insulators. After coating, heat treatment was performed for 1 hour at $200^{\circ}C$ in a furnace to secure the durability of the coating film. Compared to the uncoated insulators, the insulators with the functional coating showed significantly improved anti-fouling characteristics as well as excellent adhesion to the coated insulator surface.

• Transactions on Electrical and Electronic Materials
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• v.18 no.3
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• pp.148-150
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• 2017

For the improvement of the anti-fouling features of porcelain electrical insulators, in this study, the surface of an insulator was coated with a functional material to expand the insulator's self-cleanness. The anti-fouling and mechanical features of the functional film coating of ceramic substrates made from components like an electrical insulator were analyzed. The coating methods that were used were spray coating, dip coating, and fabric coating. Following the coating, the contact angle of the coated surface was measured, revealing that the spray coating method offered the lowest angle ($13.7^{\circ}$) and a strong hydrophilic feature. The anti-fouling analysis showed that the anti-fouling features improved as the contact angle decreased. The mechanical properties - hardness and adhesion - were both excellent at 9H and 5B, respectively, regardless of the coating method that was used.

• Corrosion Science and Technology
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• v.9 no.6
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• pp.270-275
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• 2010

Technical issues of steel industry change along with other industrial progresses. Traditionally, steel protection from corrosion environment was the major issue and galvanic metal coatings were mainly used to extend the lifetime of steel products. Nowadays, requirements for steel have become more diversified. More various surface and material properties are required from different field of applications. Naturally, functional surface coating has become one of the most studied areas in steel industry. For functional surface coating, various process technologies and coating products are investigated. In this article, recent trends of functional coating technologies and products are introduced with brief technical descriptions of representative coating products.

• Journal of the Korean Ceramic Society
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• v.45 no.10
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• pp.610-617
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• 2008

Multi-walled carbon nanotube(CNT) reinforced hydroxyapatite composite coating with a thickness of $5{\mu}m$ has been successfully deposited on Ti substrate using aerosol deposition(AD). The coating had a dense microstructure with no cracks or pores, showing good adhesion with the Ti substrate. Microstructural observation using field-emission scanning electron microscopy(FE-SEM) and transmission electron microscopy(TEM) showed that CNTs with original tubular morphology were found in the hydroxyapatite-CNT(HA-CNT) composite coating. Measurements of hardness and elastic modulus for the coating were performed by nanoindentation tests, indicating that the mechanical properties of the coating were remarkably improved by the addition of CNT to HA coating. Therefore, HA-CNT composite coating produced by AD is expected to be potentially applied to the coating for high load bearing implants.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.1
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• pp.19-26
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• 2003

In recent years, numerous studies have been carried out to find out the possible substitution of PE-coated paperboards used in packaging of watery or oily foods. Accordingly, this study was carried out to obtain the basic data for producing higher functional coating agents for pulp mold by evaluating various kinds of mixed coating agents. At that time, two kinds of synthetic coating agents(AKD, PYA) and three kinds of natural coating agent(CMC, corn starch, oxidized starch) were used for making the mixed coating agents respectively. Physical properties of coated paperboards were tested. Conclusions obtained from this study were as follows. Based on concentrations, the proper mixture ratios were 10:90(AKD:CMC), 10:90(AKD:corn starch), 10:90(AKD:oxidized starch), 40:60(PVA:CMC), 20:80(PVA:corn starch) and 20:80(PYA:oxidized starch). The mixed coating agent of PYA:corn starch(20:80) was the most efficient coating agent. Consequently, water and oil resistance were improved even with much addition of natural coating agents. We consider that they can be suitable for the packaging used in the storage of higher moisture vegetables and other food, and also can be suitable for oily fried food.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.524-524
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• 2012

Thermal Barrier Coating (TBC)은 미사일, 로켓발사체와 같이 고온에 노출되는 장비를 열로부터 보호하기 위한 코팅이다. 일반적인 Thermal Barrier Coating (TBC)은 모재와 코팅층간의 낮은 접합력과 높은 열충격으로 인한 박리가 많이 나타난다. 그래서 접합력을 높이고, 열충격을 줄이기 위해 모재와 코팅층 사이에 본드코팅층을 만든 Duplex - Thermal Barrier Coating (Duplex-TBC)이 개발되었다. 그러나 Duplex - Thermal Barrier Coating (Duplex-TBC)은 금속재료인 본드코팅층과 세라믹재료인 탑코팅층 사이에서 박리가 많이 발생한다. 이러한 문제점을 해결하기 위해 두 가지 분말을 동시에 코팅하여 본드코팅과 탑코팅의 경계가 없는 Functional Gradient Material - Thermal Barrier Coating (FGM-TBC)의 연구가 필요하다. 본 연구에서는 Functional Gradient Material - Thermal Barrier Coating (FGM-TBC)의 열충격 특성에 미치는 진공 플라즈마 용사 조건의 영향을 조사하였다. Functional Gradient Material - Thermal Barrier Coating (FGM-TBC)는 진공 플라즈마 용사장치를 사용하여 Cu-Cr 합금위에 코팅하였다. 거리, Carrier gas flow, 그리고 챔버 내부의 압력을 달리하여 제조하였다. 사용한 분말은 본드코팅용으로 Amdry 962와 내열 세라믹코팅을 위해 204NS를 사용하였고, 각각 분말 공급조건을 조절하여 두 분말의 비율을 달리하였다. 제조한 Functional Gradient Material - Thermal Barrier Coating (FGM-TBC) 코팅은 전기로에서 50분간 가열한 후, 수조에서 10분간 냉각하는 열충격 실험을 통해 열차폐 성능을 평가 하였다. 이러한 과정에서 진공 플라즈마 용사 조건 및 FGM 조성과 비율이 내열충격 특성에 미치는 영향을 미세조직학적 관점에서 고찰하였다.

• Journal of the Korean Ceramic Society
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• v.52 no.5
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• pp.338-343
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• 2015

To prevent an interfacial reaction between the anode and the electrolyte layer during the conventional high-temperature co-firing process, an anode-supported type cell with a thin-film electrolyte was fabricated by low-temperature ceramic thick film coating process. Ni-GDC cermet composite was used as the anode material and YSZ was used as the electrolyte material. Open circuit voltage and maximum power density were found to strongly depend on the surface uniformity of the anode functional layer. By optimizing the microstructure of the anode functional layer, the open circuit voltage and maximum powder density of the cell increased to 1.11 V and $1.35W/cm^2$, respectively, at $750^{\circ}C$. When a GDC barrier layer was applied between the YSZ electrolyte and the LSCF cathode, the cell showed good stability, with almost no degradation up to 100 h. Anode-supported type SOFCs with high performance and good stability were fabricated using a coating process.

• Journal of the Semiconductor & Display Technology
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• v.13 no.1
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• pp.35-41
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• 2014

UV curable transparent hard coating materials have been developed to improve the mechanical and optical properties of PET substrate. The coating materials were synthesized using various urethane acrylate oligomers, monomers, photo initiators, and leveling agents. The materials were coated on PET substrates and UV cured. The hard coated PET films were shown to have the good scratch resistance and transparency. When the urethane acrylate oligomer with more functional groups was introduced into the coating solution, the mechanical and optical properties were improved. However the higher concentration of 9-functional oligomer resulted in the decrease of workability. The addition of trimethylolpropane ethoxylate$(EO/OH)_9$ triacrylate(TMPETA) to coating solution improved the workability and properties. As a result, the UV cured film from the formulation of urethane acrylate oligomer with 9-functional groups, TMPETA as a monomer, IRACURE 754 as a photo initiator and BYK-340 as a leveling agent showed the best mechanical and optical properties in this study.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.1 s.113
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• pp.45-53
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• 2006

This study was carried out to produce high functional and biodegradable coating agents for pulp mold by evaluating various kinds of biodegradable polymers. Five kinds of biodegradable polymers were used. In addition, the mixture of the carboxymethylated starch and biodegradable polymers(${\kappa}$-carrageenan, chitosan) were used for mixed coating agents. Physical properties of coated paperboards were evaluated. Conclusions obtained were as follows. 4% ${\kappa}$-carrageenan and 5% chitosan showed higher water and oil resistance. 10% sodium alginate, 4% corn zein and 15% polycaprolactone showed high water resistance while no improvement was found on oil resistance. The optimum mixture ratios for the mixed coating agents were 90:10(carboxymethylated starch : ${\kappa}$-carrageenan) and 50:50(carboxymethylated starch : chitosan). Since these mixed coating agents have excellent biodegradability with higher water and oil resistance, these can be used for the environmental-friendly coating agents.