• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.377-382
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• 2010

건물의 대형화 고층화로 고강도 콘크리트의 사용이 증대되면서 고강도 콘크리트의 화재 시 폭열 대책이 필요하다. 본 연구는 전국 화력발전소에서 매립되는 Bottom Ash와 EPS를 재활용하여 건축소재의 내화기준에 만족하고 자원순환 소재의 새로운 개발방향을 제시하고자 난연성이 가미된 경량콘크리트 패널을 개발하여 그 난연 성능 및 벽체로서의 성능을 실험하였다. 실험은 Bottom Ash를 활용한 코팅 경량골재를 2개 Type으로 개발하여 단위중량, Flow, 압축강도, 열전도율, 부착강도, 건조수축, 흡수율, 난연 성능을 평가하였다. 그 결과 대부분의 데이터가 KS기준에 맞게 나왔으며, 난연 성능 또한 1급으로 나왔다. 이로서 폐자재인 Bottom Ash와 EPS를 재활용하여 화재 시 난연성능이 확보됨은 물론 국가성장핵심 사업인 녹색성장에 걸맞은 새로운 경량콘크리트 패널을 개발할 수 있게 되었다.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.1
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• pp.83-92
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• 1997

An experimental study of the application of Silica fume for the high strength concrete was conducted. Nine specimens with three different contents of silica fume, 0%, 10%, 20% and with three water-cement ratio 30%, 40%, 50% were tested. Results shows that 10% of silica fume and 30% of water-cement ratio has a maximum strength with 700kg/$cm^2$ of compressive strength and 64kg/$cm^2$ of splitting tensile strength and 100kg/$cm^2$ of flexural strength. Slump value of the tested samples decreases with increasing water-cement ratio and elapsed time of silica fume. Splitting tensile strength$({\sigma}_f)$ and flexural strength $({\sigma}_f)$ and static modulus of elasticity(E) can be correlated with compressive strength $({\sigma}_c)$ from a regression analysis.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.105-107
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• 2018

기존에 부유 해양구조물을 바다에서 고정시키기 위하여 수심의 2배 이상의 길이를 사용하는 잉여 계류로프는 해저바닥에서 유동하게 되어 해저 자연환경을 훼손하고, 해저바닥과 잦은 접촉으로 인해 마모로 손상되어 태풍 등 자연재해에서 부유구조물과 양식어장 등의 유실 등 잦은 피해 발생과 유동으로 부유물의 정확한 위치파악이 어려워 안전사고의 원인이 된다. 현재 계류로프로 사용되는 섬유로프와 쇠사슬(Chain)의 단점(전단 취약, 고중량, 부식, 내마모, 해양어패류 부착 등)을 개선하며, 수심의 길이만 연결 할 수 있어 정해진 위치를 이탈하지 않고 쇠사슬이 가지고 있는 장점(고인장력)을 지닌 계류로프에 대해 연구 하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07b
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• pp.553-555
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• 2005

본 논문은 모든 항전장비 가운데서도 조종사의 신속한 상황인식과 수많은 정보의 처리를 위하여 지속적으로 발전이 이루어지고 있는 조종석 디스플레이 시스템의 개량형 설계를 제안한다. 현재 항공기 조종석 시스템은 아날로그식 계기판과 함께 다수의 2-D 컬러 디스플레이를 배열한 모델을 사용하고 있다. 본 논문에서 차세대 조종석을 위해 제안하는 시스템은 미공군에서 개발 중인 방식을 도입하여 3-D와 2-D를 흔용한 소수의 대형 디스플레이로 디지털 신호만을 사용한 시스템에 OLED(Organic Light Emitting Diodes) 소자를 적용한 것이다. 이 시스템은 상용칩을 수용한 고성능의 컴퓨터 시스템을 이용하여 초당 50,000개의 3-D triangle을 최신화하여 밝은 지형과 어두운 지형 투명도, 지형특성, 비가시적 지형을 시현한다. 본 설계의 구현을 통하여 고성능의 신호 집약적 시스템 설계의 우수성과 차세대 소자로 각광받는 OLED 디스플레이 채택을 통한 디스플레이 시스템 상의 가시도 향상 및 중량감소 등의 효과가 있어 조종석 디스플레이 시스템의 실용도가 개선들 수 있음을 제안하였다.

• Polymer(Korea)
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• v.26 no.5
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• pp.615-622
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• 2002

Weather-resistant coatings were prepared by mixing a synthesized mill-base and let-down silicone/acrylic resin in weight ratios of 4 : 6, 3 : 7, and 2 : 8. The weatherability of the prepared coatings was tested. The thermal stability, general physical properties, and weatherability of the films of the coatings were improved with silicone content. Among the three mixing ratios mentioned, the ratio of 2 : 8 was the most suitable for the preparation of weather-resistant Coatings. The coatings containing 30 wt% of silicone proved to be a high weather-resistant coating.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.11a
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• pp.317-322
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• 2004

In this study the structural design of conveyor frame was carried out for the high efficiency gantry crane which can improve the productivity of the container transportation job by reducing cycle time. When the gantry crane was operated, the conveyor frame was deflected largely by its deadload and the total weight of containers placed on it. Therefore thicknesses of conveyor frame to minimize its deadload were designed by the size optimization using ANSYS program as the bending stress and the deflection of frame due to this simulation satisfied their required values.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.2
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• pp.79-84
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• 2015

Pre-drying of 'Fuyu' persimmon was performed right after harvesting from a farm. Pre-drying conditions were varied with room temperature (RT) for 1 day to 7 days, low temperature (LT, at $20{\sim}30^{\circ}C$) for 1 day to 4 days, high temperature (HT, at $30{\sim}40^{\circ}C$) for 3 h to 12 h, and ultra-high temperature (UT, at $50{\sim}60^{\circ}C$) for 30 min to 120 min. Weight loss of pre-dried persimmon was increased from 1.62% up to 2.96% with increased pre-drying temperature and time. Pre-drying at RT resulted more significant weight loss of persimmon compared to that of pre-drying at HT. Minimum firmness loss of persimmon stored at $0^{\circ}C$ for 100 days was obtained at the condition of HT for 6 h. Rate of peel blackening was decreased from 31.5% to 16.4% and 10.9% by pre-drying at HT for 6 h and 9 h, respectively.

• Journal of the Korea Convergence Society
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• v.7 no.1
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• pp.177-182
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• 2016

In order that the track vehicle utilized on the purpose of heavy industry and military affair may endure the vehicle body with heavy weight, the link surrounding the mobile wheel is affected with the great force by the load transferred at the vehicle body. This happened force gives rise to a decline in the durability throughout the track. In this paper, the models with the shapes of track pads in common use are designed and the model at which the wear of track pad and the damage of link can be decreased effectively is contrived. Also, by applying this study result to the design of track vehicle, it can contribute to the safe design for damage prevention and durability improvement. It is possible to be grafted onto the convergence technique at the designed factor of pad shape and show the esthetic sense.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.3
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• pp.44-51
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• 2016

This paper presents the characteristics of the energy absorption in an expansion tube type impact absorber that is applied to a high weight drop tester and the use of a response surface methodology to predict the impact energy absorption. In order to identify the characteristics of the energy absorption, a set of finite element analysis was conducted with Abaqus Explicit. Moreover, the ISCD-II sampling method and a first order polynomial were used to build a response surface. As a result, we demonstrated that the impact energy could be controlled by four main design variables, namely an expansion pipe's thickness, inner radius, pressing die's expansion angle and expansion ratio. Additionally, we observed the relationship between the four main design variables and the impact energy absorbing time, displacement, and maximum impact force.

• Journal of Conservation Science
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• v.21
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• pp.49-58
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• 2007

Among the treatment results of test samples of the antique lacquer-ware, the treatment with PEG#3,350 40% solution displayed excellent effect with low shrinkage ratio; in weight gain the treatment with Sucrose 19%+Glycerin 1%(t-butanol 5% in water) solution showed consistent increase. However during the impregnation process of Sucrose, the weight of the testing samples decreased by dehydration because the inner part of the test samples and the treatment solution showed concentration gradient. Therefore, we concluded longer impregnation period should be necessary to prevent dehydration. Since both higher and lower molecular weight treatment chemicals could penetrate into the wood of the lacquer-ware, air drying and conditioning after impregnation treatment with high concentration chemicals would be possible, as well as vacuum freeze-drying.