• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1300-1302
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• 1998

Residual resistance ratio ( RRR ) of Cu/Nb-Ti Superconductor wire was evaluated by fixed point method. Our measured value of RRR showed good consistency with the average value obtained from round robin test conducted by IEC/TC 90. Our test results showed that the coefficient of variation ( COV ) was kept within 2 %

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제34회 춘계학술대회논문집
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• pp.61-65
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• 2010

초저온 추진제를 사용하는 액체로켓용 인젝터의 개발을 위해서는 단일 인젝터의 수류/연소시험을 통해 인젝터의 수력학적 특성 및 혼합, 미립화 등의 분무특성에 대한 연구가 필수적이다. 본 연구에서는 대학실험실 급에서 운용할 수 있는 범위의 가압식 초저온 추진제 공급장치 및 LabVIEW를 이용한 Cyclogram 제어 및 데이터 수집장치 등을 구축하였다. 제작된 시험장치를 이용하여 스월-동축인젝터의 $LN_2-GN_2$ 초저온 수류시험 및 분무 가시화를 수행하였다. 또한 LOX-$GCH_4$ 추진제 조합의 연소시험을 위한 연소기와 추력대를 설계 및 제작하였다.

• 대한금속재료학회지
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• 제48권11호
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• pp.965-973
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• 2010

The small punch creep (SPC) test has recently received much attention as a new alternative to the conventional uniaxial creep test because it needs only a miniature-sized specimen directly detached from an operating system or component without any serious sampling damages. However, it is difficult to obtain the equivalent uniaxial creep data directly from the SPC data. As a specimen is deformed by a punch in the SPC test, the test result is sensitive to the friction between them. Finite element analyses with various friction coefficients was performed and showed a tendency of increased SPC life with an increased friction coefficient. The necking position predicted by the SPC simulation with a proper friction coefficient showed good agreement with that observed from the real SPC test. Finally, a noble method to convert the SPC load and displacement rate into the equivalent uniaxial creep stress and strain rate, respectively, was established in this study.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.745-746
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• 2005

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.747-748
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• 2005

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.929-931
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• 2006

In this experiment, we have investigated that the transported space charge between sub-pixels in AC-plasma cell discharge. The test pulse 30 V, $5{\mu}s$ was applied to the address electrodes of neighbor cells of discharge occurred cells. And we have measured the transported space charge between sub-pixels in accordance with the various last sustain pulse widths t(time gap between the rising edges of sustain and test pulses) of 0.2 to $3{\mu}s$. It was observed that the peak value of transported space charge has been shown to be 21.5pC at $1.0{\mu}s$. And the IR peak value have been occured after $0.51{\mu}s$ with respect to sustain voltage.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 추계학술발표회
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• pp.887-888
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• 2005

• Preventive Nutrition and Food Science
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• 제3권4호
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• pp.329-333
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• 1998

Cell wall (lactic acid bacteria-sonicated precipitate ; LAB-SP) and cytosoll(lactic acid bacteria-sonicated supernatant ; LAB-SS) fractions were prepared from kimchi fermenting lactic acid bacteria such as Leuconostoc mesenteroides, Lactobacillus brevis, Lactobacillus fermentum , Lactobacillus plantarum and Pediococcus acidilactici, with Lactobacillus acidophillus isolated from yogurt. Using the Ames mutagenicity test and SOS chormotest system, the antimutagenic acitivity of those cell fractions was studied . One hundered eighty $\mu$l of LAB-SP from lactic acid bacteria isolated from kimchi, excepting Pediococcus acidilactici, supressed the mutagenicity of 4-nitroquinoline-1-oxide(4-NQO) in Ames mutagenicity test and SOS chromotes system , by above 90% and 60% , respectively. LAB-SP from lactic acid bacteria also inhibited the mutagenicity mediated by 3-amino-1-methyl-5H-pyrido [4,3-b]indole (Trp-P-2). Lactobacillus fermentum, Lactobacillus plantarum, and Lactobacillus acidphillus had higher antimutagenicity against Trp-P-2). Lactobacillus fermentum , Lactobacillus plantarum , and Lactobacillus acidphillus had higher antimutagenicity against Trp-P-2 than the other lactic acid bacteria. However, LAB-SS of lactic acid bacteria did not show any mutagenic activity against 4-NQO in Ames mutagenicity test and SOS chromotest systems. On the mutagenicity of MEIQ and Trp-P-2 , LAB-SS of lactic acid bacteria from kimchi or dairy products exhibited a weaker inhibitory effect than LAB-SP of those bacteria. These results represent that, whether the lactic acid bacteria from kimchi are viable or nonviable, antimutagenic acitivity was still effective. We suggest that the strong, antimutaganic activity of lactic acid bacteria might be found in the cell wall fraction , rather than in the cytosol fraction.

• 한국항공우주학회지
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• 제44권9호
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• pp.814-824
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• 2016

본 논문에서 제안한 우주기반기술 검증용 큐브위성의 명칭은 STEP Cube Lab. (Cube Laboratory for Space Technology Experimental Project)으로 주요임무는 국내 산학연에서 기수행된 우주핵심기술을 발굴하며, 자체 개발 탑재체를 궤도 검증하는 것이다. 상기의 임무 구현을 위해 체계 레벨에서의 요구조건에 따라 전자조립 및 기능시험을 수행하였다. 또한, 비행 소프트웨어 설계의 유효성을 입증하였으며, 발사 궤도 열 환경시험을 통해 수락수준의 비행모델 검증을 완료하였다. 본 논문에서는 FM EIT, 발사 궤도 열 환경에서 수행한 기능시험의 일련 과정을 소개하고자 한다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.1078-1079
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• 2005