• International Journal of Precision Engineering and Manufacturing
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• 제3권2호
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• pp.95-101
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• 2002

The propagation rate(da/dt) prediction parameter and the microstructure properties of creep crack in domestic 3.3NiCrMov steel were investigated at 550$\^{C}$ by using 0.5" CT specimen under constant load(4090N) and constant Ct(300∼4000N/mhr) condition that was maintained during crack growth of 1mm distance. C＊ usually increased with crack length though load was reduced in order to maintain constant Ct value as crack growth and considerably showed the scatter band, but Ct depended on load line displacement rate and represented a good relation with da/dt. At constant toad and Ct region, crack growth slope was 0.900 and 0.844 each, in the other hand C＊ slope was 0.480. Fully coalesced area(FCA) ahead of crack tip was increased as Ct value increase to the critical value, and after that value FCA decreased. The average diameter ditribution of cavity in FCA showed the greatest value about 1.5 ㎛ when Ct=2000N/mhr. The increasing of Ct in FCA view point enlarged the size of damage area and the size reached to maximum 800 ㎛ when Ct=2000N/mhr.

• 한국컴퓨터정보학회논문지
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• 제21권4호
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• pp.123-129
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• 2016

This study had a purpose to find the correlation between academic achievement and entrance examination score using FCA and framing a concept of university academic achievement and entrance examination score and then, building concept lattice. The subject for this analysis was admission materials of freshmen in computer engineering department at A university located in Chungcheong area in 2010. Also 56 students in total were subjects for the score analysis of their first semester from 2010 to 2014. The major findings of this study were as follows. We organized and extracted many-valued context, concept lattice, associated rules using FCA. And we analyzed the correlation between University academic achievement and entrance examination score using FCA. The conclusions were as follows. We could get meaningful analyzed results using FCA. University academic achievement had lower relativeness with entrance examination score and female students had higher university academic achievement than male students. The improvement points are summarized below. It is necessary to improve the ratio and application method of the university admission factors and to increase the regular admission for a university. And programs for completing College-preparatory programming for male students in low university academic achievement are necessary.

• Journal of Welding and Joining
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• 제28권1호
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• pp.86-91
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• 2010

In the present study, two-dimensional plane deformation thermo elasto-plastic analysis has been carried out, in order to investigate the thermal and mechanical behaviour (residual stress, plastic strain, magnitude of stress and their distribution and production mechanism) on multi-pass FCA butt weldment of high strength EH36-TMCP ultra thick plate. Moreover, this study can be considered as a basis for analysing the fracture toughness, KIC, and its effect on welding residual stress redistribution with notch on multi-pass FCA butt weldment, in future. The results of welding residual stress obtained from thermo elasto-plastic analysis has been compared and verified with the results measured by XRD.

• Journal of Welding and Joining
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• 제23권4호
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• pp.27-33
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• 2005

Quantitative evaluation was performed on the microstructure of flux-cored arc(FCA) weld metal using a method blown as IIW scheme. It was mainly intended to figure out any practical difficulties in applying this method and also to provide the consumable makers with basic guide line in developing FCA welding consumables far better properties. Assessment of the experimental results showed IIW scheme was quite reliable in the low heat input range where the acicular ferrite was a major constituent. However, in the high heat input range, some scatter was noticed as the other phases like grain boundary ferrite and Widmansttaten ferrite become dominant. It implies that the accuracy of IIW scheme depends on the faction of microstructural constituents and it become worse as the fraction of latter two phases increases. This tendency was discussed in terms of the characteristics of those two phases. In addition, base line microstructure of rutile type FCA weld metal was addressed for developing new FCA welding consumables intended for higher heat input welding.

• Biomolecules & Therapeutics
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• 제2권3호
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• pp.292-297
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• 1994

This study was conducted to investigate antigenic potential of DA-3030, a recombinant human granulocyte-colony stimulating factor, in guinea pigs and mice. In the active systemic anaphylaxis test, the guinea pigs sensitized with 1.25 or 12.5 $\mu\textrm{g}$/head of DA-3030 alone did not show any anaphylactic reaction. In the homologous passive cutaneous anaphylaxis reaction, anti-DA-3030 antibody was not detected in guinea pigs sensitized with 1.25 or 12.5 $\mu\textrm{g}$/head of DA-3030 alone. On the other hand, the guinea pigs sensitized with 12.5 $\mu\textrm{g}$/heed of DA-3030 incorporated in Freund's complete adjuvant(FCA) or 1 mg/head of ovalbumin incorporated in FCA showed anaphylactic reaction. Anti-DA-3030 antibody was also detected in those guinea pigs. In immunodiffusion test using the sera sensitized with DA-3030 incorporated in FCA, precipitating antibodies were detected only in the sera sensitized with DA-3030 or DA-3030 incorporated in FCA showed. In 24-hour heterologous PCA reaction with sera of C57BL/6 mice immunized with 1.25 or 12.5 $\mu\textrm{g}$/head of DA-3030 alone, none of the sera showed positive reaction. But sera of the animals immunized with 12.5 $\mu\textrm{g}$/head of DA-3030 incorporated in aluminum hydroxide gel(Alum) or 5 $\mu\textrm{g}$/head of ovalbumin incorporated in alum showed positive PCA reaction. DA-3030 did not cause anaphylactic shock or passive cutaneous anaphylaxis in guinea pigs and mice when given alone although DA-3030 incorporated in FCA or Alum induced anaphylactic shock and passive cutaneous anaphylaxis. From these results, it may be concluded the DA-3030 does not induce systemic allergic reaction when administered alone in its clinical use.

• 분석과학
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• 제8권3호
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• pp.221-227
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• 1995

$Ca^{2+}$에 대하여 특이한 선택성을 보이는 광섬유형광센서에 대하여 연구하였다. 이 센서는 $Ca^{2+}$과 형광성 킬레이트를 형성하는 단백질 Calmodulin(CaM)을 사용하였으며, 두 갈래로 된 광섬유 다발의 끝면에 플루오르세인 이소티오시아네이트로써 형광 표지된 Calmodulin(FCaM)으로 만든 용액을 투석막 안에 넣어서 제작하였다. 이 센서의 감응 메카니즘은 FCaM이 $Ca^{2+}$과 결합하여 킬레이트를 형성할 때에 나타나는 형광 스펙트럼의 이동 현상을 바탕으로 한다. CaM은 $Ca^{2+}$과 결합할 때에 형태변화를 일으키며, 이로 인해 유발되는 FCaM의 형광세기 변화로써 농도를 결정하였다. 광전자증배관으로 형광의 세기를 측정하여 $Ca^{2+}$에 대한 검정곡선을 작성하였으며, 센서의 $Ca^{2+}$에 대한 검출한계와 $Mg^{2+}$, $Eu^{3+}$, $La^{3+}$들에 의한 방해효과, 감응 시간 및 수명을 조사하였다.

• 한방재활의학과학회지
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• 제23권2호
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• pp.49-61
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• 2013

Objectives : This study was conducted to determine whether or not Kangwhaldoche-tang(Qianghuodaozhi-tang) (KDT) aqueous extracts can protect articular cartilage losses on the Freund's complete adjuvant(FCA)-induced rat rheumatoid arthritis. Methods : 520, 260 or 130 mg/kg of KDT were orally administered once a day for 14 days from 14 days after FCA treatments, and 15 mg/kg of dexamethasone was intraperitoneally administered as reference drug in this experiment. Changes on the body weight, knee circumferences, gross arthritis score, inflammatory tissue prostaglandin(PG) $E_2$ levels were monitored with cartilage collagen components and glucosaminoglycans(GAGs) compositions - chondroitin sulphate, heparin sulphate and hyaluronic acid in the present study. Results : As results of FCA treatment, classic rheumatoid arthritis featuring dramatic decreases of the body weights, cartilage collagen and GAGs contents with increases of the knee circumferences, gross arthritis scores and inflammatory tissue $PGE_2$ levels, were demonstrated in the present study. However, these changes from FCA - induced rheumatoid arthritis were clearly inhibited by treatment of dexamethasone and all three different dosages of KDT. Although overall anti-inflammatory effects of KDT 520 mg/kg were lowered than those of dexamethasone 15 mg/kg treated rats, KDT 520 mg/kg showed more favorable preserve effects on the cartilage GAGs and KDT 260 mg/kg treated rats showed similar preserve effects as compared with dexamethasone 15 mg/kg in this experiment. Conclusions : The present results supported that over 75 mg/kg of KDT showed favorable anti-arthritic effects on the FCA-induced arthritis mediated by suppression of $PGE_2$, representative inflammatory mediator, and may help improve rheumatoid arthritis.

• 해양환경안전학회지
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• 제22권5호
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• pp.554-563
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• 2016

선박엔진은 잔사유를 에너지원으로 활용하여 운항할 수 있으며, 이를 활용한 선박에서 환경 규제와 경제성을 모두 만족시키는 다양한 방안들이 모색되고 있다. 그 중에 한 방안으로 연료 첨가제를 활용하는 기술이 있을 수 있다. 분산제와 연소촉진제는 잔사유 활용 시 엔진의 연소특성 촉진에 기여할 것이라는 기대를 받고 있다. 따라서, 본 연구에서는 연소성 분석 장비(FIA/FCA)와 열 중량 분석 장비(TGA)를 활용하여 잔사유 연료첨가제가 혼합된 잔사유의 연소성을 분석하였다. 연소성 분석 장비(FIA/FCA)의 결과로는 연소에 의한 일의 총량을 분석하도록 분석법이 개발되었으며, 이 때문에 본 연구를 통하여 동일 장비를 활용하면서도 연소 효율을 간단하게 평가할 수 있는 방안을 제시하였다. 연소성 분석 결과인 ROHR 곡선으로부터, 단순한 삼각함수를 활용하여 연소특성을 예측할 수 있는 방안을 제시하였으며, 이 기법을 활용하여 기존의 압력 곡선과 유사한 결론을 도출할 수 있었다. 열 중량 분석(TGA)의 경우 연료유의 증발 특성에 민감하게 반응함을 확인하였고, 첨가제가 연료유 증발에 효과적으로 작용함을 확인하였다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2001년도 가을 학술발표논문집 Vol.28 No.2 (2)
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• pp.304-306
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• 2001

Various methods for blind source separation (BSS) are based on independent component analysis (ICA) which can be viewed as a nonlinear extension of principal component analysis (PCA). Most existing ICA methods require certain nonlinear functions, the shapes of which depend on the probability distributions of sources (which is not known in advance), whereas FCA is a linear learning method based on only second-order statistics. In this paper we show how BSS can be achieved by FCA, provided that sources are spatially uncorrelated but temporally correlated.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2005년도 춘계학술발표대회 개요집
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• pp.69-70
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• 2005

In order to prevent the arc blow at the FCA welding system with multi-torches, the effects of arc length on the magnetic flux at the FCA weldment was evaluated using electro-magnetic filed analysis. Magnetic flux density around arc are slightly increased with an increase in the arc length. Based on the FEA results, the minimum distance of torches to control arc blow was established.