• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.97-99
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• 2012

A pressure-based BOIK model considering Shock to Detonation Transition(SDT) and damage due to external fragment or bullet stimuli impact on energetic materials and analytical approach for determination of free parameters are proposed. The rate of product mass fraction(${\lambda}$) consists of ignition term that represents the initiation due to shock compression and growth term that describes propagation of detonation wave and strain term representing the morphological deformation induced by external impact.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.170-171
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• 2021

In Korea, the concentration of cities has led to the high-rise and deep-rise of buildings. In the case of such high-rise buildings, there is a high risk of fire, and the number of internal fires expanding to the outside continues to increase. The Korean Building Act continues to change the ban on combustible exterior materials, and combustible exterior materials are currently not available for buildings with three stories or more than 9 meters, and detailed test standards for finishing materials are also strengthened after the Ulsan residential and commercial fires in 2020. However, the path of fire in the actual building is through a series of processes in which the fire in the compartment grows internally and expands through openings supplied with ventilation factors. Therefore, other than just external materials, design criteria for embedded materials also need to be established. The purpose of this study is to compare standards for internal and external materials at home and abroad and to secure basic data for fire safety design of buildings based on them.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.225-229
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• 2011

The aluminum composite panel are widely used for the external materials of high rise building because of well insulation of heat and sound and improved Constructability. However, the polyethylene in main material of the aluminum composite panel shows weakness in thermal and fire resistances. For this reason, flame is spread more quickly when the fire break out. Therefore, the potentiality of fire spread to the exterior wall is high due to difficulty of early extinguishment and effect of external air. In this study, numerical investigation was performed by using FDS program for flame spread characteristics with various external air velocity and direction in ten-story building with the aluminum composite external materials. As a result, the flame spread velocity is 0.134m/s and it takes 224 seconds for flames to spread to the 10th floor without external air velocity. however, the flame spread velocity decreases 40% and it takes 348 seconds for flames to spread to the 10th floor when external air velocity is 2.5 m/s. and air direction is little effect compared to air velocity.

• 대한금속재료학회지
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• 제49권6호
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• pp.505-513
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• 2011

A magnetic device which enables the application of a strong and uniform magnetic field to thin film during sputtering was designed for controlling the magnetic anisotropy using a three dimensional finite element method, and the effects of the external magnetic field on the magnetic properties of sputtered thin films were investigated. Both the intensity and the uniformity of the magnetic flux density in the sputter zone (50 mm ${\times}$50 mm) was dependent on not only the shape and size of the magnet device but also the magnitude of stray fields from the magnet. For the magnet device in which the distance between two magnets or two pure iron bars was 80-90 mm, the magnetic flux density along the direction normal to the external magnetic field direction was minimum. The two row magnets increased the magnetic flux density and uniformity along the external magnetic field direction. An Fe thin film sputtered using the optimized magnet device showed a higher remanence ratio than that fabricated under no external magnetic field.

• 한국분말재료학회지
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• 제18권2호
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• pp.168-171
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• 2011

We investigate grain growth behavior of poly-crystalline Mg sheet having strong basal fiber texture using phase field model for grain growth and micro-elasticity. Strong initial basal texture was maintained when external load was not imposed, but was weaken when external biaxial strain was imposed. Elastic interaction between elastic anisotropy of Mg grain and external load is the reason why texture evolution occurs.

• 한국재료학회지
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• 제12권7호
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• pp.580-586
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• 2002

The effect of processing and designing variables such as pouring temperature(1400 or $1500^{\circ}C$), inoculation and risering design(T and H type) on the formation of defects such as external depression, primary and secondary shrinkage cavities in GC150 gray cast iron was investigated. In T type risering design, external depression or primary shrinkage cavity due to liquid contraction was formed in all of the eight cases. Regardless of its modulus value, the riser could not function properly in T type risering design because directional solidification was not promoted toward the riser. On the other hand, the four cases of H type risering design in which thermal sleeves were set onto the risers produced defect-free castings. In both types of the risering designs, secondary shrinkage cavity caused by solidification contraction was not observed in the casting because of the expansion pressure due to graphite precipitation and the application of rigid pep-set mold. The degree of external depression or primary shrinkage cavity was reduced with lowered pouring temperature. The effect of inoculation was diminished because of the high carbon equivalent of GC 150 gray cast iron.

• 한국정보통신학회논문지
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• 제11권3호
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• pp.549-554
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• 2007

본 논문에서는 다양한 전극재료로부터 빛의 밝기와 저항을 측정분석 하였다. 외부전극의 새로운 재료와 공정기술은 램프제작에서 개선된 특성을 위해서 매우 중요하다. 본 실험에서는 외부 전극을 형성하기 위한 다른 세가지 타입은 구리와 알루미늄 테이핑, 은 접착, 니켈과 구리의 무전해 도금 방법들이다. 밝기측정에서 램프유리위에 외부 전극을 위한 니켈과 금 플레이팅 방법에 의한 휘도의 결과를 나타내었고, 또한 다른 전극재료를 사용한 방법에 의한 결과를 비교 하였다. 니켈과 금플레이팅 공정의 측정된 저항값은 휘도의 개선된 결과에도 불구하고 다소 높은 저항값을 나타내었다. 니켈과 니켈/금 도금방법은 가장 좋은 결과를 나타내었고, 사전 표면 식각에 따라 약간의 다른 휘도를 나타내었다.

• Membrane and Water Treatment
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• 제1권2호
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• pp.159-169
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• 2010

The effect of external recycle on the performance of dialysis in countercurrent-flow rectangular membrane modules was investigated both theoretically and experimentally. Theoretical analysis of mass transfer in parallel-flow device with and without recycle is analogous to heat transfer in parallel-flow heat exchangers. Experiments were carried out with the use of a microporous membrane to dialyze urea aqueous solution by pure water. In contrast to a device with recycle, improvement in mass transfer is achievable if parallel-flow dialysis is operated in a device of same size with recycle which provides the increase of fluid velocity, resulting in reduction of mass-transfer resistance, especially for rather low feed volume rate.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제50권2호
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• pp.116-120
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• 2024

External nasal splints are commonly used for immobilization following nasal fracture reduction or rhinoplasty procedures. The literature documents the use of various materials like thermoplastic materials, aluminum, Orthoplast, fiberglass, plaster of Paris, and polyvinyl siloxane. These materials are bulky, time-consuming, expensive, and cumbersome to use, and have been associated with complications including contact dermatitis and epidermolysis. Furthermore, they cannot be retained if the situation warrants prolonged stabilization and immobilization. We introduce a new technique using readily available scalp vein catheter flanges as an external nasal stent. The technique is easy to master, inexpensive, and limits edema and ecchymosis, while stabilizing the reconstructed nasal skeleton in position during the healing period.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2006년도 춘계종합학술대회
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• pp.878-881
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• 2006

본 논문에서는 다양한 전극재료로부터 빛의 밝기와 저항을 측정하였고 분석하였다. 외부전극의 새로운 재료와 공정기술은 램프제작에서 개선된 특성을 위해서 매우 중요하다. 본 실험에서는 외부전극을 형성하기 위한 다른 세가지 타입은 구리와 알루미늄 테이핑, 은 접착, 니켈과 구리의 무전해 도금 방법들이다. 밝기측정에서 램프유리위에 외부전극을 위한 니켈과 금플레이팅 방법에 의한 휘도의 결과를 나타내었고 또한 다른 전극재료를 사용한 방법에 의한 결과들과 비교하였다. 니켈과 금플레이팅 공정의 측정된 저항값은 휘도의 개선된 결과에도 불구하고 다소 더 높은 저항값을 나타내었다. 그러나 니켈과 니켈/금 도금방법은 가장 좋은 결과를 나타내었고 사전 표면 식각에 따른 약간의 다른 휘도를 나타내었다.