• 한국소음진동공학회논문집
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• 제23권10호
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• pp.920-927
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• 2013

The requirement of acoustic performance about underwater acoustic material which is used in underwater environment more increases. Underwater acoustic material was made by viscoelastic material such as a rubber and a polyurethane etc. In order to increase an acoustic performance, several kinds of inclusions were added to viscoelastic material. In this paper, acoustic modelling and analysis techniques were introduced and the acoustic characteristics of underwater acoustic material were studied. Echo reduction and transmission loss were calculated with volume fraction of inclusion in the material. Also the characteristic impedance and the input impedance of underwater acoustic material were obtained and effects on the echo reduction and transmission loss of material were discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 춘계학술대회 논문집
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• pp.43-46
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• 1995

We fabricate a bottom gate a-Si:H TFT on N-Type <100> Si wafer. According to the variation of gate and drain voltage, the hysteresis characteristic curves were measured experimentally. Also, we showed that the model predict the hysteresis characteristic successfully. Drain current on the hysteresis characteristic currie showed an exponential variation. Hysteresis area of TFT increased with the drain voltage increase and decreases with the drain voltage decrease.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 춘계학술대회 논문집
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• pp.163-166
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• 1995

A solar cell I-V (current-voltage) characteristic measurement facility is crucial, for the characteristic of solar cells, The solar cell I-v tester has been designed and fabricated to characterize the solar cell at SAIT.

• 한국의상디자인학회지
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• 제12권1호
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• pp.51-59
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• 2010

The purpose of this study is to help understanding of Korean fashion image by studying of design factor and formative characteristic. The methods of this study are the study of academic literatures as well as practical study through the analysis of case studies about actual works. The summary of this study's results is like followings. First, Perspectives seeing formative characteristic on Korean fashion image are Shape with a line, color, material, pattern, accessories. Second, Design factors deciding Korean fashion image are pattern, then in order of shape, color, material, accessories. Third, In results on design factor deciding Korean fashion image, when fashion designers focus on pattern, pattern is focused on without regard for other design factor. But color and material are accompanied by other design factor in expressing Korean fashion image. As fashion design point expressing Korean astetic, use of pattern is minimized other design factor, color and material are used with other design factor, then Korean fashion image will come out more than other time else. If We develop Korean fashion design to concentrate on shape and pattern, Korean fashion culture will be known to world people and beautiful value of Korean fashion will be handed effectively.

• 한국전기전자재료학회논문지
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• 제20권11호
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• pp.995-999
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• 2007

We investigated the characteristics of a flux-lock type superconducting fault current limiter(SFCL) considering magnetization characteristic of iron core. The flux-lock type SFCL, like other types of SFCLs using the iron core, undergoes the saturation of the iron core during the initial fault time. Therefore, if the design to prevent the saturation of the iron core is considered, the effective fault current limiting operation can be achieved. Through the analysis for its equivalent circuit including the magnetization characteristic of the iron core, the limiting impedance of the flux-lock type SFCL was drawn. The magnetization currents and the limited currents of SFCL, which were dependent on the winding direction and the turns' ratio between two coils, were investigated from the short circuit experiment. It was confirmed that their experimental results agreed with the analysis ones.

• Nuclear Engineering and Technology
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• 제42권4호
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• pp.426-433
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• 2010

The characteristic X-rays emitted from materials after gamma ray exposure was simulated and measured. A CdTe semiconductor detector and a $^{57}Co$ radiation source were used for energy spectroscopy. The types of materials could be identified by comparing the measured energy spectrum with the theoretical X-ray transition energy of the material. The sample composition was represented by the $K_{\alpha1}$-line (Siegbahn notations), which has the highest intensity among the characteristic X-rays of each atom. The difference between the theoretic prediction and the experimental result of K-line measurement was < 0.61% even if the characteristic X-rays from several materials were measured simultaneously. 2D images of the mixed materials were acquired with very high selectivity.

• 한국건설관리학회논문집
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• 제10권1호
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• pp.16-25
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• 2009

건설산업에서 자재와 관련된 비용은 프로젝트 특성에 따라 다르지만 일반적으로 원가구성비 측면에서 40% 이상을 차지한다. 최근 대형화, 전문화, 복잡화 되어가는 건축 공사에서 자재의 반입, 이동 및 적재공간의 협소로 인해 자재관리가 매우 복잡하다. 하지만 대부분의 경우 자재관리는 현장 관리자의 경험에 의존해 관리되고 있으며 건설관리분야 중 자재관리의 중요성에 대한 인식도 낮은 실정이다. 이에 대한 건설 산업에서 자재관리에 대한 연구도 활발히 진행되고 있다. 본 연구에서는 자재의 속성에 따른 MTS(Make-to-stock), ATO(Assemble-to-order), MTO(Make-to-order), ETO(Engineered-to-order)의 네 가지 분류 방법과 자재 조달 특성 및 자재 고유 특성 분석을 통하여 현장 자재의 효율적인 공급관리를 위한 자재의 속성별 관리체계를 분석한다. 이를 이용하여 자재 속성별 자재관리 프로세스를 제안한다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.573-574
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• 2006

The planarization technology of Chemical-mechanical polishing(CMP), used for the manufacturing of multi-layer various material interconnects for Large-scale Integrated Circuits (LSI), is also readily adaptable as an enabling technology in MicroElectroMechanical System (MEMS) fabrication, particularly polysilicon surface micromachining. However, general LSI device CMP has partly distinction aspects, the pattern scale and material sorts in comparison with MEMS CMP. This study performed preliminary CMP tests to identify slurry characteristic used in general IC device. The experiment result is possible to verify slurry characteristic in MEMS structure material.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.830-834
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• 2008

Resilient materials are generally used for the floating floors to reduce the floor impact sound. Dynamic stiffness of resilient material, which has the most to do with the floor impact sound reduction. The resilient materials available in Korea include EPS (Styrofoam), recycled urethane types, EVA (Ethylene Vinylacetate) foam rubber, foam PE (Polyethylene), glass fiber & rock wool, recycled tire, foam polypropylene, compressed polyester, and other synthetic materials. In this study, we tested floor impact sound reduction characteristic to a lot of kinds of resilient material. The result of test showed that the amount of the Light-weight impact sound reduction appeared by being influenced from this dynamic stiffness of resilient material. As the decreasing dynamic stiffness of resilient material, the impact sound reduction amount is increased, especially in the low frequency domain.

• KSTLE International Journal
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• 제4권1호
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• pp.27-30
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• 2003

The basic principles of tribo-systems and study method based on tribe-systems are introduced in the paper, Based on the viewpoint of tribe-systems, the experiment on tribology characteristics of friction lining material in multi-rope friction hoist is carried out. The research result shows: tribology characteristics of friction material are not its inherent characteristic but system characteristics of the tribo-systems, the“sliding-rope”of multi-rope friction hoist can be divided into“safety sliding-rope”and“fault sliding-rope”, study on friction material only based on characteristic of system where friction material exists possesses practical significance.