• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.6
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• pp.59-71
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• 2019

The numerical analysis of ablative thermal protection systems (TPS) for solid rockets has been carried out with various in-house codes since the 1960s. However, the application scope of commercial codes has been expanded by adding subroutines and user-defined functions (UDF) to codes such as Fluent, Marc, and ABAQUS. In the past, the flow, thermal response and structural analysis of TPS have been performed using separate approaches. Recently, research has been conducted to interrelate them. In this paper, the thermal response characteristics of thermal protection materials, the in-house codes for thermal response analysis, and the research trends of flow-thermal-structure analysis of TPS using commercial codes were reviewed.

• Fashion & Textile Research Journal
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• v.12 no.1
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• pp.122-128
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• 2010

This study examined several dyeing properties, physiological responses and comfort sensation of cotton knit underwear dyed with bamboo charcoal. The cotton knit underwear dyed with bamboo charcoal and treated with chitosan showed 99.9% antibacterial property and improved deodorization, and colorfastness. Eight children with atopic dermatitis worn underwear dyed with bamboo charcoal during 4 months. Their parents reported fewer itches of children. Wearing cotton knit underwear dyed with bamboo charcoal and non-dyed with bamboo charcoal respectively, these eight children rested for 20 minutes, then exercised for 10 minutes, and then rested for 30 minutes in the room maintained $28{\pm}1^{\circ}C$ and $50{\pm}5%R.H.$ Children's rectal temperature, skin temperature and microclimate inside garment of two types of cotton knit underwear were compared. As a result, the rectal temperature and skin temperature were higher when children were wearing underwear dyed with bamboo charcoal than non-dyed underwear. The microclimate temperature and microclimate humidity at the back of children were lower when children with underwear dyed with bamboo charcoal exercised and recovered.

• Journal of fish pathology
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• v.15 no.1
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• pp.17-24
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• 2002

The charcoal effects on the immune responses of flounder, Paralichthys olivaceus were studied. Fish were fed an experimental diet supplemented with 1%, 3% or 5% of charcoal to a commercial diet. Several factors such as weight gain, hematological parameters, nonspecific immune responses and resistance against Edwardsiella tarda were evaluated 4 and 8 weeks after the administraion. The changes of body weight and lysozyme activities were not signigicant among tested groups. But cholesterol and total protein concentration in the blood were significantly lower in the 5% supplemented group than in the control. The production of superoxide by macrophage from the head kidney, examined by NBT reduction, was significantly higher in the 3% charcoal supplemented groups than in the control. The survival rate after an artificial challenge with 1×10^exp(7) cells of E. tarda per fish was significantly the highest in the 3% charcoal supplemented group.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.2
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• pp.46-51
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• 2003

The charcoal is known to have gas adsorption capability and is used frequently to mitigate the unpleasant smells from food and clothing. It is also used to treat water to remove dissolved organic and inorganic substances. In this paper, we applied the several different kinds of charcoals to the papers in three different ways to investigate if charcoal application method affects its gas adsorption capability. Wet end addition, making multiply, and coating method were tested. Specific ethylene gas adsorption capabilities were measured. Experimental results shows that manufacturing conditions of the charcoal itself changed its gas adsorption properties. The boxes used for agricultural produces, and the packaging paper for flowers are to be well fitted application for the charcoal added paper. Mulch paper, which needs opacity and air permeability with proper strength properties, is another candidate for the application of charcoal added paper.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.54.2-54.2
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• 2011

야금학적 정련 공정 중 슬래그 처리, 일방향 응고, 플라즈마-전자기유도용해 공정을 적용한 태양전지용 실리콘 제조 기술에 관한 연구를 수행하였다. 원소재인 금속급 실리콘을 제조하기 위해원재료로 규석, 코크스(Cokes), 숯, 그리고 우드칩(Wood chip)을 사용하였으며, 150kW급 DC 아크로(Arc furnace)를 이용하여 순도 99.8% 금속급 실리콘을 제조하였다. 제조된 용융 상태의 금속급 실리콘은 슬래그와 반응시켜 불순물을 제거하였다. SiO2-CaO-CaF2 계의 슬래그를 이용하였으며, 금속급 실리콘과 슬래그의 질량비 및 반응 시간에 따른 실리콘 불순물 특성을 평가하였다. 이후 고액 계면이 제어 가능한 일방향 응고 장치를 이용하여 금속불순물을 제거하였다. 고액상태의 온도 조건 및 응고 시간에 따른 불순물 농도 변화를 평가하였으며, 순도 6N급의 실리콘을 제조하였다. 마지막 공정으로 스팀 플라즈마 토치와 냉도가니가 적용된 전자기 유도 용해장치를 이용하여 붕소와 인을 제거하였다. 플라즈마 토치 가스로는 아르곤, 스팀, 수소를 이용하였다. 붕소와 인의 제거율은 각각 94%와 96%를 달성하였으며, 최종 순도 6N급의 실리콘을 제조하였다.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.2
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• pp.354-363
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• 2004

PCDD/F (Polychlorinated dibenzo-p-dioxins and dibenzofurans) in both of treated fabric and untreated fabric for working clothes of a municipal waste incineration were determinated. The treated fabric for working clothes was developed for less exposure of PCDD/F in municipal waste incinerations. The total concentrations of PCDD/F in some parts such as surface, middle layer, inside for treated and untreated fabric were investigated. The I-TEQ value of surface was 0.23370ng TEQ/g for treated fabric, 0.15355ng $.$ TEQ/g for non-treated fabric. On the other hand, the value of middle layer was 0.00077ng $.$ TEQ/g, 0.00177ng $.$ TEQ/g, respectively. The surface of the treated fabric containing high levels PCDD/F was caused by absorption of them. Therefore, PCDD/F of the treated fabric in middle layer was less I-TEQ value than that of the untreated fabric. The treated fabric makes effect on preventing PCDD/F from permeating into human body.

• Journal of Digital Contents Society
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• v.15 no.6
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• pp.745-749
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• 2014

Mankind has long made images. From cave paintings in the Old Stone Age when the dye was red clay, charcoal, or red iron ore to the modern digital images on the bases of 3D tools like Maya, images have been made through various methods. The basis of society's classification is the development of human beings and technologies. When we are familiar with three elements-technology, human, and art-we are able to create an image suitable for the trend of the times. As a consequence, we brought the trivium that had been taught by the monks in the Middle Age to set our subject to the trivium of the digital age. In this paper, we are going to put technology, human, and art into actual animation to check its theoretical discussion value.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.651-663
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• 2017

Experimental results of $30^{\circ}-15^{\circ}$ nozzles were compared with numerically calculated convective heat transfer coefficients using FLUENT, Boundary Layer Integration Method and Bartz predictions. Also, the convective heat transfer coefficients were calculated by using FLUENT and boundary layer integration method for NASA HIPPO nozzles according to the characteristics of combustion gas and the correlation between pressure and pressure was compared. Finally, thermal analysis of NASA HIPPO nozzle was performed to compare the ablation thickness and char depth according to the combustion gas characteristics.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.521-528
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• 2017

In this paper, the numerical analysis for heat conduction of silica/phenolic composite material, which is used for solid rocket nozzle liner or insulator, was conducted. 1-D Finite Difference Method for the analysis of silica/phenolic during the firing of solid rocket motor was used to calculate the heat conduction considering the surface ablation and the thermal decomposition. The boundary condition at the nozzle wall took into account the convective heat transfer, which was obtained by integration equation. The numerical results of the surface ablation and char depth were compared with the results of test motor that is TPEM-10. It was found that the result of calculation is favorably agreed with the thermal response of test motor.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.4
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• pp.107-119
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• 2013

바이오매스 가스화는 세계적인 증가 추세에 있는 에너지 수요를 충족할 수 있는 기술 중의 하나이다. 바이오매스 가스화를 통해서 농업 폐기물 등 다양한 바이오매스 자원을 에너지로 전환할 수 있고 $CO_2$ 배출량 또한 줄일 수 있다. 본 연구에서는 COMSOL$^{(R)}$ 3.4 소프트웨어를 이용하여 바이오매스 원료와 운전 조건에 따른 가스화 효율 및 합성가스 조성의 변화를 분석하였다. 원료와 구동조건을 최적화하기 위해 가스화 모델을 세우고 원료와 구동조건을 달리하여 합성가스의 성분을 분석 및 예측하였다. 이 모델은 물리적인 실험을 통해 알고 있는 조건을 통해서 합성가스 성분을 시간에 따라 예측할 수 있다. 모델을 이용하여 함수비 5~30 %, 공기중 산소함량 5~50 %, 공기공급 유량 5~45 L/min, 온도 973~1273 K의 조건에서 합성가스의 성분을 예측한 결과 실제 실험 결과와 일치하는 것을 알 수 있다. 모델링 결과 양질의 합성가스를 생산하려면 원료의 회분함량이 적어야 하고 수소 함량이 높은 합성가스를 생산하려면 반응 온도가 높게 유지되고 원료의 함수비가 높아야 한다. 가스화장치의 온도를 높이면 합성가스의 성분 중 CO의 함량이 많아지고, CO의 함량이 많아지면 가스의 발열량이 높아지는 것을 알 수 있다. 또한 CO의 농도가 높고 발열량이 높은 합성가스를 생산하기 위해서는 ER값은 작아야 한다.