• 한국재료학회지
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• 제18권2호
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• pp.65-68
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• 2008

The present work was performed to investigate the effect of coiling temperature on the annealed texture in Cu/Nb-added ultra-low-carbon steels. The ultra-low-carbon steels were coiled at 650 and $720^{\circ}C$, respectively. The result showed that the Cu-added ultra-low-carbon steel at a low coiling temperature produced a desirable annealed texture related to good formability. On the other hand, Nb-added ultra-low-carbon steel at a high coiling temperature also produced a desirable texture. This is attributed to the effect of Nb, which retards recrystallization during the coiling process.

• 열처리공학회지
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• 제17권2호
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• pp.78-86
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• 2004

Effects of the annealing parameters on the formation of ferrites transformed at low temperatures were studied in cold-rolled ultra low carbon steels with niobium and/or chromium. Niobium and chromium were found to be effective in the formation of the low temperature transformation ferrites. The low temperature transformation ferrites more easily formed when both higher annealing temperature and longer annealing time, allowing substitutional alloying elements to distribute between phases, are in combination with faster cooling rate. It was found from EBSD study that the additions of niobium or chromium resulted in the increase in the numbers of high angle grain boundaries and the decrease in those of the low angle grain boundaries in the microstructures. Both granular bainitic ferrite and bainitic ferrite were characterized by the not clearly etched grain boundaries in light microscopy because of the low angle grain boundaries.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1999년도 추계연구발표회 논문개요집
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• pp.20-21
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• 1999

• 한국염색가공학회지
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• 제16권3호
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• pp.8-13
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• 2004

This research aimed at scrutinizing the comparative dyeability of some disperse dyes at low temperature on ultra-microfiber polyester, islands in the sea type (0.05 denier), which has claimed utmost fastness and improved uptake of dyeing. Comparisons of dyeability, such as rate of dyeing and color depth, on ultra-microfiber polyester were evaluated by H.T. exhaust dyeing method and followed by the test of rubbing fastness. To achieve high wet fastness, some commercial disperse dyes, Terasil WW and Megacron dyes, which have been recently launched for excellent wash fastness, have been examined compared with conventional disperse dyes, C.I Disperse Red 167 and C.I Disperse Orange 30.

• 한국세라믹학회지
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• 제46권2호
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• pp.146-154
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• 2009

It is necessary to minimize the thickness of Ni inner electrode layer and to improve the coverage of inner electrode, for the purpose of developing the ultra high-capacity multi layered ceramic capacitor (MLCC). Thus, low temperature sintering of dielectric $BaTiO_3$ ceramic should be precedently investigated. In this work, the relationship between dielectric properties of MLCC and batch condition such as mixing and milling methods was investigated in the $BaTiO_3$(BT)-Dy-Mg-Ba system with borosilicate glass as a sintering agent. In addition, several chip properties of MLCC manufactured by low temperature sintering were compared with conventionally manufactured MLCC. It was found that low temperature sintered MLCC showed better DC-bias property and lower aging rate. It was also confirmed that the thickness of Ni inner electrode layer became thinner and the coverage of inner electrode was improved through low temperature sintering.

• 전기전자학회논문지
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• 제24권2호
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• pp.673-676
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• 2020

본 논문에서는 IT 기술을 접목한 초저온 순환 냉각 방식의 전신 관리 시스템을 제안한다. 제안하는 시스템은 다음과 같은 특징들을 가진다. 첫 번째로 초저온으로 냉각된 질소가스를 관리기 내부에서 순환시킴으로서 유지비용을 최소화한다. 두 번째로 온도센서와 산소농도센서로 측정된 정보를 기초로 질소가스를 공급하여 안전한 초저온 전신관리를 제공한다. 세 번째로 사용자의 신장을 입력한 후에 전자동 리프트를 이용하여 제어 가능한 편리한 초저온 전신관리를 제공한다. 네 번째로 접근이 쉽고 조작이 편리한 GUI 및 전신관리 시스템 운영을 위한 관리자 전용 웹 프로그램의 GUI를 제공한다. 제안된 시스템의 성능을 평가하기 위하여 공인시험기관에서 실험한 결과는 온도센서 정확도는 세계 최고 수준인 ±5%의 범위에서 측정이 되었고, 전신관리 온도범위는 세계 최고 수준(-110℃ ~ -140℃)보다 넓은 -110℃ ~ -150℃의 범위가 측정되었다. 또한, 습도는 세계 최고 수준인 40% 미만으로 측정이 되었고, 산소농도도 세계 최고 수준인 18% 이상으로 측정되었다. 따라서 본 본문에서 제안한 IT 기술을 접목한 초저온 순환 냉각 방식의 전신 관리 시스템의 성능이 세계 최고 수준과 동일한 결과를 산출하였기 때문에 그 효용성이 입증되었다.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.35-39
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• 2000

Large-area high-temperature superconducting (HTS) films, filter design and damage-free processing technique have been developed to fabricate low insertion loss and sharp skirt filters. Further, long life cryocooler, low temperature low noise amplifier (LNA) and cryocable have been developed to assemble HTS filter subsystem for IS-95 and IMT-2000 mobile telecommunication. The surface resistance of the films was about 0.2 milli-ohm at 70 K, 12 GHz. An 11-pole HTS filter for IS-95 telecommunication system and a 16-pole HTS filter for IMT-2000 telecommunication system were designed and fabricated using 60 {\times}$ 50 mm$^2$ and one half of 3-inch diameter YBCO films on a 0.5-mm-thick MgO substrate, respectively. We have assembled the filter and low temperature LNA in a dewar with the cryocooler. Ultra low-noise (noise figure: 0.5 dB at 70 K) and ultra sharp-skirt (40 dB/1.5 MHz) performance was presented by the IS-95 filter subsystem and the IMT-2000 filter subsystem, respectively.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2018년도 공동국제학술발표회
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• pp.86-86
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• 2018

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2008년도 제38차 학술발표대회
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• pp.192-194
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• 2008

The study has focused on the dyeing properties of 4 kinds of high temperature type mono azo disperse dyes, widely used in the dyeing factory, under the ultra low liqour ratio (1:4) dyeing condition. Among those, C.I. Disperse Red 343 and C.I. Disperse Blue 79 showed un-levelled dyeing results from the ultra low liquor ratio dyeing bath as well as poor dispersion stability under the high temperature. We recommended some leveling agents to improve the leveling behavior of these dyes mentioned above. The milling technology should be further developed to achieve the dispersion stability.

• 한국약용작물학회지
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• 제16권6호
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• pp.439-445
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• 2008

This study was performed to investigate a methodology of improving immune activities of Berberis koreana Palibin by ultra high pressure on low temperature extraction process. Extraction yield was enhanced up to more than 35% by above process, compare to the control and extraction average. The cytotoxicity on human kidney cell (HEK293) was showed below 20.4%, 21.6% in adding 1.0 mg/ml of the highest concentration. Generally, the extracts by ultra high pressure extraction process showed less toxicity about 5% than the other processes. It could tell that toxic materials that existing in the plant could be reduced or broken by ultra high pressure process due to can be broken bond such the hydrogen bond, the electrostatic bond, the van der Waals bond, and the hydrophobic bond, can be broken by high pressure. The result could be employed to develop a new type of functional food from B. koreana Palibin by low temperature high pressure process.