• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.4 no.3
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• pp.167-173
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• 2011

Since many blood pressure pulse analyzer made to measurement of a pulse wave in quantitative way has been started, some sorts of pressure sensors are being developed. The result could differ and this cause either type of sensor or module shape, when pulse wave is measured. In this paper, calculate and compare the pressure sensor's stress distribution according to thickness of PDMS coating and existence of guide through Finite Element Method. As a result, the center of pressure sensor's stress increase as much as 24% as it is reduced as much as 0.3 mm that the PDMS coating thichness of pulse diagnostic sensor module, on the other hand the surrouding censor of center sensor's stress is reduced as much as 4.9%, and transmissive proportion of stress is small as little as 2.7%, When coating has guide.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.12
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• pp.961-968
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• 2020

In this study, the effective thermal conductivity and elastic modulus of heat-resistant coating materials are analyzed by using micromechanical computational models. Three-dimensional computational models for HfC-coated carbon/carbon composites were created with Simpleware, and finite element analysis was performed. The porosity and thickness changes in the coating layer were taken into account to identify the tendency of effective material properties. In addition, the coupon specimen was produced to compare the thermal conductivity measured by experiments with the one obtained by finite element analysis according to temperature changes, and the analysis results were close to the measured values. This confirms that micromechanical computational analysis is appropriate in the calculation of effective material properties of coating composites.

• Korean Journal of Microbiology
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• v.49 no.3
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• pp.275-281
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• 2013

Probiotics have been reported to benefit human health by modulating immunity, lowering cholesterol, improving lactose tolerance, and preventing some cancer. Once ingested, probiotic microorganisms have to survive harsh conditions such as low pH, protease-rich condition, and bile salts during their passage through the gastro-intestinal (GI) tract colonize and proliferate to exert their probiotic effects. The dual coating technology, by which the bacteria are doubly coated with peptides and polysaccharides in consecutive order, was developed to protect the ingested bacteria from the harsh conditions. The aim of the study was to evaluate the viable stability of a doubly coated blend of four species of Bifidobacterium by comparing its bile/acid resistance and heat viability in vitro with that of the non-coated blend. After challenges with acid, bile salts, heat, and viable cell counts (VVCs) of the dual coated and non-coated blend were determined by cultivation on agar plates or flow cytometric measurement after being stain with the BacLigtht kit$^{TM}$. The results showed that the dual coated blend was much higher resistant to the acidic or bile salt condition than the non-coated blend and heat viability was also higher, indicating that the dual coating can improve the survival of probiotic bacteria during their transit through the GI tract after consumption.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2396-2401
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• 2009

This study is on development of UV-cured hard coating compounds which have more improved abrasion resistance than existing UV-cured urethane-acrylic resin, to prevent a surface of a widely used PVC tile as a constructive material from being scratched. To make a high abrasion resistant hard coating solution compared to UV-cured urethane-acrylic resin which has no abrasion resistance and been used for PVC tiles, we added powder substances of different abrasion resistant level, $Al_2O_3$(Al-160SG-3), $Al(OH)_3$(SH-8W), $SiO_2$(KS-5000), etc., to the resin, changing their contents from 10% to 30% against quantities of resin, and compounded it using Ring-Mill. After coating PVC tiles with the hard coating solution using bar-coating method that can adjust a thickness, we estimated some surface properties-abrasion resistance, pencil hardness, adhesive power, thickness of coating, and so on. As a result, a hard coating solution added 30% $Al_2O_3$ powder to the resin had the finest surface properties-the first grade in abrasion resistance, H in pencil hardness, 100% in adhesive power, and a hard coating solution which showed excellent solidity and abrasion resistance has smaller particle size, higher powder content, and thicker coating thickness.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.973-980
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• 2004

To evaluate the antioxidative effect of rice coated with maengjong-juk extract in vivo system, rice coated with maengjong-juk extract diets were fed to NZW rabbit for 16 weeks and lipid peroxidation, protein oxidation, activities of antioxidative enzymes and total glutathione content in tissues were measured. TBARS contents in liver and spleen were significantly decreased in maengjong-juk extract diet group compared to control group, while those in kidney and heart tissue were not significantly different. Maengjong-juk extract diet suppressed the protein oxidation significantly in liver, spleen, kidney and heart tissues. Hepatic total SOD, Cu$.$Zn-SOD and Mn-SOD activities of maengjong-juk extract diets were significantly higher than those of control diet. GSH-Px and catalase activities of maengjong-juk extract diet were higher than those of control, while GR activities show no significant difference between the two groups. Total hepatic glutathione content was significantly increased by maengjong-juk extract diet. According to this study, many antioxidative materials and phytochemicals in maengjong-juk extracts seems to protect tissues from oxidative stress by stimulating antioxidative systems in atherosclerotic rabbit fed high cholesterol diet.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.50-53
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• 1998

코팅이나 접착제 분야에서 대기 중에서 불안정한 이소시아네이트기를 보호하기 위해 phenol, oxime, caprolactam계 화합물을 사용하는 봉지 방법을 본 연구에서 이용하고자 하였다. 선천적으로 위의 화합물들로 봉지된 이소시아네이트기는 결합쇄로 carbamate를 형성하나 이들은 열에 의해 특정 온도 영역에서 해리 되면서 다시 이소시아네이트기가 재 생성되는 과정을 거친다.(중략)

• Proceedings of the Korean Ceranic Society Conference
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• 2004.04b
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• pp.38.1-38.1
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• 2004

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.75.1-75.1
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• 2011

화석연료의 고갈과 온실가스 배출의 증가로 지속 가능한 친환경 에너지 생산이 요구되는 가운데, 태양광 발전은 이러한 조건을 만족시키는 에너지 생산 방안으로 주목받고 있다. 태양광 발전은 태양 직사광을 이용한 발전 방법 때문에 실외에 설치되어야 하며 이에 따라 외부의 충격이나 오염물질로부터 태양전지 패널을 보호하기 위한 보호층이 필수적이다. 그러나 보호층에 의한 입사광의 반사 및 먼지나 황사에 의한 보호층의 오염 등은 태양전지의 발전 효율을 감소시키는 요인으로 작용하여 이에 대한 대응이 필요하다. 본 연구에서는 PET 필름에 나노 임프린트 리소그래피 및 핫 엠보싱 공정을 이용하여 moth-eye 반사방지 패턴을 형성함으로써 보호층에서의 입사광 반사를 억제하였다. 또한, 이러한 반사방지 패턴에 초소수성 자기조립단분자막을 코팅하여 표면 에너지를 낮춤으로써 먼지 및 황사에 의해 오염되었을 경우에도 빗물에 의해 오염 물질이 쉽게 씻겨 내릴 수 있는 자정기능을 부여하였다. 이러한 반사방지를 통한 입사광 투과량의 향상 및 초소수성 표면에 의한 자정작용에 의하여 태양전지의 발전 효율이 증가되었다.

• Composites Research
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• v.14 no.6
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• pp.32-37
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• 2001

It is known that recoating or protection with glass-tube can prevent FBG sensor from being affected by birefringence. However, the effect on the strain transfer of such treatment has not been verified yet. Three types (uncoated, recoated and glass-tube protection) of FBG sensors are fabricated to verify the effect on the strain transfer of each treatment. The strain from each sensor embedded into a graphite/epoxy composite specimen was compared with that of ESG attached on the surface through the tensile test. And the signal characteristics of each sensor were also compared using the tensile test of a tapered aluminum specimen which was under the state of strain gradient.

• Journal of Hydrogen and New Energy
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• v.17 no.2
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• pp.181-192
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• 2006

PEC전지 전극으로 사용될 수 있는 CdSe는 수용액상에서 광부식이 심하기 때문에 투명한 보호막이 필요하다. TiO2는 광부식이 심한 광전극의 보호막으로 적당하며 이 논문에서 화학적 방법(전기증착과 화학조증착)을 이용하여 산성용액이나 알칼리용액에서 TiO2 박막을 제조하여 광흡수나 광전류를 측정하였다. XRD를 이용해서 제조된 TiO2 박막의 결정성을 확인하였으며 막의 표면특성은 SEM으로 측정하였으며 광흡수 특성이 관찰되었다. 제조된 TiO2 박막의 광전류는 100 mw/cm2의 광세기를 가지는 제논 램프를 이용하여 측정하였다. CdSe에 TiO2박막을 코팅했을 때의 CdSe막의 광흡수와 광전류를 측정하여 TiO2 코팅효과를 관찰하였다.