• Proceedings of the KIEE Conference
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• 1998.07d
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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 %

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.61-65
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• 2010

To research and develop a liquid rocket engine injector, it needs empirical studies about the hydrodynamic and spray characteristics such as pressure drop, mixing and atomization. In this study, the design and implementation of lab-scale cold-flow/hot fire test stand which can supply cryogenic propellant and be controlled by time-critical LabVIEW cyclogram logic has been done. In order to visualize the spray of a liquid-centered swirl coaxial injector in cryogenic condition, LN2-GN2 cold-flow test has been done, and combustor assembly and thrust bed for LOX-$GCH_4$ hot-fire test have been fabricated.

• Korean Journal of Metals and Materials
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• v.48 no.11
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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.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.745-746
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• 2005

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.747-748
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• 2005

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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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.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.887-888
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• 2005

• Preventive Nutrition and Food Science
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• v.3 no.4
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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.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.9
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• pp.814-824
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• 2016

The mission objective of STEP Cube Lab. (Cube Laboratory for Space Technology Experimental Project) classified as a pico-class satellite is to find space core technologies researched at domestic industry or university and to verify these technologies on mission orbit. To implement this objective, system level electrical integration and function test (EIT) by using developed flight software were performed in compliance with system requirements. And the effectiveness of the flight model (FM) was verified through launch and thermal vacuum test at acceptance level. This paper will introduce a series of process of electrical function tests for FM EIT, launch and thermal vacuum tests.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.1078-1079
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• 2005