• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.188-189
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• 2006

ITVDC 해저케이블의 절연은 주로 지절연물(紙絶緣物)에 고점도의 컴파운드를 강제함침(mass-impregnation)하여 제조된다. 이러한 강제 함침 작업은 제조 공정 중 가장 긴 시간이 소요되며, 케이블의 절연 특성을 결정하는 중요한 요소가 된다. 그러나 함침은 복잡한 물리현상이며, 함침이 진행되는 동안 케이블의 내부 상태를 직접 관찰하기 곤란하다. 따라서 기존의 제조 경험을 바탕으로 작업조건에 충분한 안전율을 적용하는 실정이다. 이와 같은 강제함침 작업조건을 합리화하면 공정에 소요되는 시간뿐 아니라 함침조건을 조정하여 케이블 절연 특성의 향상까지 기대할 수 있다. 본 논문에서는 당사가 HVDC 해저케이블 개발과정에서 함침에 관한 이론적 검토와 간이 함침실험을 통해 정립한 함침조건에 대해 기술하였다.

• Journal of the Korean Wood Science and Technology
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• v.31 no.5
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• pp.15-22
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• 2003

This study was carried out to investigate the properties of sawdust board impregnated with phenol resin according to the density and resin content of board. The sawdust board were manufactured to target densities of 0.4, 0.5, 0.6, 0.7 g/cm³ and resin content of 5, 10, 15, 20% made from Pinus densiflora S. et Z., Larix. kaemferi C. and Pinus koraiensis S. et Z. The impregnation process were executed in two ways, the application of vacuum pressure then followed by atmospheric pressure, and the application of vacuum pressure with ultrasonic vibration then followed by atmospheric pressure. The density of impregnated sawdust board increased as density and resin content of sawdust board increased, but impregnation rate decreased. The density, impregnation rate, bending strength and brinell hardness of sawdust board in impregnated vacuum pressure with ultrasonic vibration then nonpressure were higher than those of vacuum pressure then nonpressure. In this results, the impregnation rate is increased in vacuum pressure with ultrasonic vibration then nonpressure, it has affected the properties of sawdust board impregnated with phenol resin.

• Polymer(Korea)
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• v.25 no.1
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• pp.122-132
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• 2001

Thermoplastic film infusion process was investigated by using a rubber tool, which intrinsically contains a thermally-expandable characteristic and effectively compensates for the pressure loss caused by thermoplastic polymer infusion. Increasing temperature up to the melting temperature of matrix, the polymer melt subsequently infused into the dry fabric, but the pressure was successfully sustained by the rubber tool. Even with the decreased resin volume, the rubber tool produced sufficiently high elastic force for continuous resin infusion. Combining D'Arcy's law with the compressibility of rubber tool and elastic fiber bed, a film infusion model was developed to predict the resin infusion rate and pressure change as a function of time. In addition, the film infusion process without the rubber tool was viewed and analyzed by a compression process of the elastic fiber bed and viscous resin melt. The compressibility of fiber bed was experimentally measured and the multiple-step resin infusion was well described by the developed model equations.

• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.116-118
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• 2003

정밀주조에 사용되는 왁스형을 기존의 수작업과 금형을 이용하는 방법으로 제작하지 않고 SLS형 RP로 캐스트폼형을 만들고 여기에 왁스를 함침시켜 왁스형을 제작하는 공정을 제안하였다. 왁스형의 정밀도를 향상시키기 위해 캐스트폼형 예열시간, 왁스 함침시간, 왁스 함침 회수 등 중요한 공정변수를 변화시켜 가며 왁스형을 만들었다. 왁스형의 정밀도를 측정한 결과 예열시간이 적어도 30분 이상일 때 정밀도가 우수한 제품을 얻었으며, 왁수를 두 번이상 함침할 때 정밀도가 우수하였다. 왁스형의 표면거칠기는 예열시간이 늘어날수록 향상된 표면조도를 얻을 수 있었다.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.04a
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• pp.907-911
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• 2000

타포린 제조 공정에서 함침의 발생 여부를 검사하는 것은 동 업계의 중요한 문제이다. 본 논문에서는 모폴로지를 사용한 함침 검사를 수행하였다. 모폴로지를 이용한 변환들 중의 하나인 Top hat 변환을 사용하였으며, 이 변환은 완만하게 불균일한 배경에서 급격한 변화를 가지는 물체를 추출하는데 탁월한 성능을 가진다. 이를 사용한 결과, 250dpi 영상에서 0.2mm 이상 크기의 함침을 검출할 수 있었다.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.244-250
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• 2012

In order to separate of carbon dioxide in the combustion exhaust gas, monoethanolamine (MEA) and piperazine (PZ) impregnated zeolite 13X adsorbents were used. A series of adsorbents were synthesized by impregnating 30, 50 and 70 wt% of MEA and PZ respectively on zeolite 13X pellet. XRD, FT-IR and BET were used to characterize the properties of impregnated pelletized zeolite 13X absorbents. In order to investigate the separation characteristics of carbon dioxide, zeolite pellet, MEA impregnated zeolite and PZ impregnated zeolite pellet were investigated at 25, 50 and $75^{\circ}C$. Amine impregnated pelletized zeolite absorbent has shown that adsorption decreases with increasing temperature. Finally, the carbon dioxide adsorption capacity when emission temperature of the combustion exhaust gas, PZ impregnated zeolite pellet was 1.8 times than zeolite pellet as well as 20 times than MEA impregnated zeolite pellet.

• Journal of Korea Foundry Society
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• v.42 no.4
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• pp.218-225
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• 2022

For hydrogen-vehicle applications (air pressure control valve housing, APCVH), an investigation was conducted to determine how micro-defects in a high- pressure die-casted Al alloy (industrial code: ALDC12) could be controlled by means of a post-treatment using an organic-based impregnation solution in order to improve the air- tightness of the die-casted Al sample. Two different impregnation solutions were proposed and its test results were compared to a imported product from Japan with respect to the processing variables used. A structural investigation of the components under study was conducted by means of computer tomography and 3D X-ray micro-CT. These observations revealed that the use of the impregnation treatment to seal micro-defects led to highly significant and beneficial changes which were attributed mainly to interconnections among inherent micro-pores. A leak test after impregnation revealed that the performance improvement rate of the die-casted Al sample was ~70% for INNO-01. Therefore, the developed impregnation solutions offer an effective strategy to control the micro-defects found in various vehicle parts via die-casting.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.1
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• pp.47-53
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• 2016

The electrolyte wetting phenomena occurring in the electrode of lithium-ion battery was studied using lattice Boltzmann method (LBM). Recently, lithium-ion batteries are being mixed with small particles on the active material to increase the capacity and energy density during the electrode design stage. The change to the mixing ratio may influence the wettability of electrolyte. In this study, the changes in electrolyte distribution and saturation were investigated according to various mixing ratios of active material. We found that the variations in mixing ratio of active material affect the wetting mechanism, and result in changes to the wetting speed and wettability of electrolyte.

• Korean Chemical Engineering Research
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• v.44 no.3
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• pp.248-253
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• 2006

In order to develope an efficient drug delivery system, experimental researches on the supercritical impregnation of ibuprofen onto mesoporous silica, MCM-41,and its drug release characteristics were performed. Supercritical carbon dioxide was adapted as an alternative solvent as it is harmless and able to avoid defects of organic solvents in drug manufacturing processes. The procedure was composed of three steps, that is, as hydrothermal synthesis of MCM-41, supercritical impregnation of ibuprofen onto MCM-41 and release of impregnated ibuprofen. Supercritical impregnation reached equilibrium within 2 h for all cases of this research and the amount of equilibrium impregnation increased with solubility of ibuprofen in supercritical carbon dioxide. Release profiles of impregnated ibuprofen showed a similar behavior for all MCM-41 with different impregnated ibuprofen.

• Composites Research
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• v.16 no.2
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• pp.68-73
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• 2003

Interfacial properties and electrical sensing fer fiber fracture in carbon and SiC fibers/epoxy composites were investigated by the electrical resistance measurement and fragmentation test. As fiber-embedded angle increased, the interfacial shear strength (IFSS) of two-type fiber composites decreased, and the elapsed time takes long until the infinity in electrical resistivity. The initial slope of electrical resistivity increased rapidly to the infinity at higher angle, whereas electrical resistivity increased gradually at small angle. Furthermore, both fiber composites with small embedded angle showed a fully-developed stress whitening pattern, whereas both composites with higher embedded angle exhibited a less developed stress whitening pattern. As embedded angle decreased, the gap between the fragments increased and the debonded length was wider for both fiber composites. Electro-micromechanical technique could be a feasible nondestructive evaluation to measure interfacial sensing properties depending on the fiber-embedded angle in conductive fiber reinforced composites.