• International Journal of Aeronautical and Space Sciences
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• v.18 no.4
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• pp.641-650
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• 2017

In order to include the design capability for a compound rotorcraft in a helicopter conceptual design and optimization framework, relevant further improvement was planned and conducted. Previously, a certain conceptual design optimization framework was developed by the present authors to design a modern rotorcraft with single main and tail rotor. The previously developed framework was further improved to expand its capability for a compound rotorcraft. Specifically, its power estimation algorithm was upgraded by using a comprehensive rotorcraft analysis program, CAMRAD II. The presently improved conceptual design and optimization framework was validated using data of the XH-59A aircraft.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.4
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• pp.11-18
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• 2006

Compound flow by confluence of two parallel flows through a convergent channel and its choking phenomenon are calculated by one-dimensional isentropic model and completely mixing model. Optical observations and pressure measurements for subsonic/subsonic compound flows are carried out and compared with the results of one-dimensional calculations. As a result, it is found that inlet conditions of one flow influence the behavior of the other flow as well as the choking condition and present experimental data agree well with the results of one-dimensional calculations.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.38-44
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• 2011

The performance experiment was tested for the velocity compound turbine of turbopump which was the main part of 75 ton class liquid rocket engine. The seal is installed between the 1st rotor and the reversing vane to reduce the leakage flow. The turbine outlet pressure of the velocity compound turbine by changing the rotating speed was compared with that of baseline turbine with single rotor including the effect on the total performance.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2007-2010
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• 2015

A new chemical inhibitor against severe acute respiratory syndrome (SARS) coronavirus helicase, 7-ethyl-8-mercapto-3-methyl-3,7-dihydro-1H-purine-2,6-dione, was identified. We investigated the inhibitory effect of the compound by conducting colorimetry-based ATP hydrolysis assay and fluorescence resonance energy transfer-based double-stranded DNA unwinding assay. The compound suppressed both ATP hydrolysis and double-stranded DNA unwinding activities of helicase with IC₅₀ values of 8.66 ± 0.26 μM and 41.6 ± 2.3 μM, respectively. Moreover, we observed that the compound did not show cytotoxicity up to 80 μM concentration. Our results suggest that the compound might serve as a SARS coronavirus inhibitor.

• Journal of the Korean Applied Science and Technology
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• v.27 no.1
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• pp.6-13
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• 2010

Esterification reaction between succinic acid and 1,4-butanediol was kinetically investigated in the presence of nontoxic organometallic compound catalyst(ESCAT-100E) at $150-190^{\circ}C$. The reaction rates measured by the amount of distilled water from the reaction vessel. The Esterification reaction was carried out under the first order conditions respect to the concentration of reactants, respectively. The overall reaction order was 2nd. The linear relationship was shown between apparent reaction rate constant and reciprocal absolute temperature. By the Arrhenius plot the activation energy have been calculated as 376.13 kJ/mol under nontoxic organometallic compound catalyst and also apparent reaction rate constant, k' was found to obey first kinetics with respect to the concentration of catalyst.

• Proceedings of the KIEE Conference
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• 1987.07b
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• pp.1046-1049
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• 1987

This paper proposes a Korean-Japanese Machine Translation System that processes unregistered words, modifiers and compound sentences. In mophological analysis, the unregistered words are processed by using unregistered word processing algorithm. The modifiers are processed by consulting noun-attributes and grammar rules. The compound sentence processing algorithm recognizes whether the sentence that includes commas is compound sentence or not. This system performs on IBM-PC/AT DOS using Prolog-1.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.463-468
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• 2002

This study investigates the variations of shear force, displacement, and fracture surface with the shear speed and the number of reflows. The experimental data of shear tests indicate that the shear force increases as increasing the number of reflows and the shear speed due to the formation of a kind of intermetallic compound, Ni$_3$Sn$_4$, on Au/Ni/Cu pad, and the work-hardening. However, general trends show that the shear force decreases due to increasing the thickness of the intermetallic compound over 4x reflow. It is observed that the intermetallic compound which is formed between solder and pad increases according to increasing the number of reflows, and the growth rate of the intermetallic compound at central region on the interface is faster than one at edge part. The general tendencies of shear force and displacement with different shear speeds are almost identical as an increase of the number of reflows.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.111.1-111
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• 2003

삼백초 지상부의 에탄올 추출농도와 추출 시간에 따른 수율, total phenol과 total flavonoid함량, DPPH 라디칼 소거능을 조사하였다. 추출 온도 9$0^{\circ}C$에서 에탄올농도를 증가시키면서 8시간동안 환류추출하였다. 추출수율과 DPPH 라디칼 소거능은 에탄올농도 40%까지는 증가하다가 60%이상에서는 감소하였고 total phenolic compound와 total flavonoid의 함량도 비슷한 경향을 보였다. total phenolic compound의 함량은 40%와 60%에서 큰 차이가 없는 반면 total flavonoid의 함량은 40%에서 더 높았다. total phenolic compound와 total flavonoid 함량, DPPH 라디칼 소거능 및 추출수율은 40% 이상에서는 큰 변화가 없어 추출용매의 조건은 40% 에탄올로 선정하였다. 40% 에탄올로 9$0^{\circ}C$에서 24시간 동안 4시간 간격으로 환류추출하였을 때 total phenolic compound와 total flavonoid 함량, DPPH 라디칼 소거능 및 추출수율은 4시간 이후 큰 차이가 없었다. 삼백초의 용매추출조건으로는 40% 에탄올, 4시간 추출하는 것이 적합하다고 판정된다.

• International Journal of Oral Biology
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• v.44 no.4
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• pp.165-172
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• 2019

Berberine has been used clinically for more than a decade to treat various diseases, has been shown to be effective in osteoblast differentiation, and is a potential treatment option for osteoporosis. However, compared with existing osteoporosis drugs, berberine is somewhat less effective. This study aimed to identify a new compound with efficacy superior to that of berberine. The osteogenic activities of various berberine derivatives were evaluated via cell differentiation in C2C12 preosteoblast cell lines. Alkaline phosphatase (ALP) staining assay and structure-activity relationship demonstrated that compound 2b had a potent osteogenic effect. Furthermore, compound 2b dose dependently increased ALP activity and showed no toxicity at the effective concentration, indicating its efficacy. Additionally, compound 2b upregulated BMP2-induced transcriptional activity in a promoter activity assay using ALP, BSP, and OC promoters.

• Journal of Haehwa Medicine
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• v.20 no.1
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• pp.153-160
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• 2011

Objective : The objective of this study is to observe the effect of Pharmacopuncture of Anti-inflammatory Herbal compound(AiC) theraphy on elbow pain Methods : The patients diagnosed as lateral epicondylitis and treated mainly with Anti-inflammatory Herbal compound(AiC). After the application of herbal acupuncture, The NRS and ROM of elbow were assessed. Results & conclusion : Symptoms of the patient such as elbow pain and dysfunction were improved after above treatments. so, it is suggested that oriental medical treatment(Pharmacopuncture of Anti-inflammatory Herbal compound(AiC)) is effective on Tennis elbow.