• 열처리공학회지
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• 제17권4호
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• pp.216-222
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• 2004

Study was focused on the quenching embrittlement property of Zircaloy-4 cladding simulated Loss Of Coolant Accident (LOCA) environment in terms of high temperature oxidation and phase transformation. Property in LOCA condition of advanced cladding that contained Nb element was also investigated. Claddings were oxidized at given temperature and given time followed by water quenching. The results showed that ${\beta}$ phase which formed at quenching stage has an influence on cladding property. In case of advanced cladding, Nb retards cladding oxidation, thus enhances quenching resistance.

• Educational Technology International
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• 제10권2호
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• pp.63-83
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• 2009

The purpose of this study was to investigate the cognitive mechanism of e-Learning contents development projects on the basis of the Shared Mental Model theory perspective. To pursue the purpose, a theoretical model and several hypotheses were developed based on relevant literature. Thirty five (35) e-Learning contents development teams composed of 202 instructional designers from for-profit professional e-Learning companies in Korea were participated in this study. For the analyses of the fit of the Model and parameter estimations, Structural Equation Modeling (SEM) method was employed. As hypothesized, e-Learning contents development team members' interaction leads to higher SMMs which in turn facilitate member satisfaction within the team. Meanwhile, the frequency of interaction among team members decreases as projects progress.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 추계학술대회 논문집
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• pp.279-280
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• 2006

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2001년도 봄 학술발표논문집 Vol.28 No.1 (B)
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• pp.157-159
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• 2001

교환기 시스템(switching system)과 같은 통신 시스템 환경에서는 매우 제한적인 시간제약하에서 명시된 이벤트들이 반드시 완료되어야 한다. 따라서, 시스템내에 유지되는 응용데이터에 대해, 매우 빠르고 균일한 접근 시간을 제공하여야 한다. 또한, 최근들어 통신 운용 환경과 교환기 소프트웨어의 복잡성의 증가로 다중테이블 죠인과 객체지향 특성과 같은 고급 기능을 포함한 보다 향상된 데이터 모델링이 요구되고 있다. 이를 위해, 본 논문에서는 1) 통신 응용 환경을 보다 쉽게 모델링하도록 다양한 설계 모델링 개념을 제공하고, 2) 죠인과 같은 연산을 위해 추가의 메모리공간이나 시간을 사용하지 않고, 객체식별자의 항해를 통해 직접 결과를 추출하는 방법에 대해 설명한다.

• 한국해양환경ㆍ에너지학회지
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• 제14권4호
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• pp.257-263
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• 2011

SBM을 이용하여 2006년 가막만의 담수, 염분, 영양염 등 물질 수지를 산정하였다. 담수유출량은 $-174.2{\sim}72.5{\times}10^3m^3/day$로 나타났으며 개방경계에서의 해수 교환에 의한 mixing volume은 $-2.4{\times}10^7\sim4.9{\times}10^7m^3/day$로 만 내외의 염분차이에 의해 크게 좌우 받았다. 육상기인 DIP와 DIN의 유입 flux의 범위는 397.0~1158 mole/day 및 1750~8328 mole/day의 범위로 다른 지역에 비해 낮았다. DIP의 소실 또는 생성은 물수지의 변동에 의해 크게 좌우 되는 특징을 보였으며, 또한, 물질체류시간에 의해 물질수지가 크게 좌우되어 NEM도 크게 달라지는 결과를 보였다.

• 한국인터넷방송통신학회논문지
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• 제15권6호
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• pp.147-154
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• 2015

최근 애자일 개발프로세스가 생산성 증대효과, 품질향상, 고객만족 등의 효용성이 입증되면서 프로젝트 추진 시 방법론 선택에 있어 전문가들에게 많은 관심을 갖게 되었다. 시대적 요구와 사용자 요구에 부응하기 위한 방법론 선정과 관련해서, 본 논문에서는 제품 기반의 Cross functional team의 문제점을 해결하고자 제안된 방법론이 Feature Team 모델이며, 이 모델이 Cross functional team을 조직하고, 이 팀이 결과물(프로덕트) 단위가 아니라, 기능단위로 여러 프로덕트에 걸쳐서 개발을 진행하는 모델이라는 점에 대해 조사하였으며, 가치-주도형 애자일 기법을 통해 계획-기반형 모델과 차이점을 제시하였다. Agile 성숙도 측정기준을 검토하였으며, PRINCE2 Agile Health-check 항목 연구를 통해 Agile 기법이 프로젝트 착수단계의 요구사항은 확정 본이 아닌 언제라도 변경될 수 있다는 것을 전제를 해서 객관적인 평가를 받는 방법에 대해 연구하고 프로젝트 팀 구성에 대해 향후 발전방향을 제시하였다.

• 한국수산과학회지
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• 제39권2호
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• pp.72-77
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• 2006

Enrofloxacin (ENRO) is one of the most commonly used fluoroquinolones for treating bacterial disease in olive flounder (Paralichthys olivaceus) farming, but its withdrawal time for industrial-scale farming has not been well established. Withdrawal times of ENRO following oral administration were evaluated in olive flounder under field conditions. Fish were held in an inland fish tank and fed a commercial mediated diet containing 5 mg/kg of ENRO for 9 days. Seven fish per sampling point were examined during and after treatment. ENRO and its major metabolite, ciprofloxacin (CIP), were analyzed using high-performance liquid chromatography with a fluorescence detector. The concentration of ENRO and CIP in muscle increased during the medication period, and then decreased rapidly The sum of ENRO and CIP concentration in olive flounder peaked on day 6, with a maximal concentration in muscle of 4.30 mg/kg. ENRO residues were eliminated rapidly; at 10 days post treatment, the level in muscle was 0.10 mg/kg, but it took about 50 days to be reduced to below 0.1 mg/kg. After 60 days, the residual concentration was below 0.1 mg/kg in all samples. The level of ENRO accumulation at the beginning of oral administration was variable, according to the farming conditions, but the overall exhaustion time was almost the same. We concluded that an adequate withdrawal period of enrofloxacin is 60 days in the case of oral administration.

• 공업화학
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• 제10권4호
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• pp.531-536
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• 1999

누출시험 장치를 이용하여 미량 물 누출 실험을 수행하였다. 2.25Cr-1Mo 시편의 누출경로는 나트륨-물 반응 생성물에 의해 plugging되는 경우가 발생하였으나, 대부분 re-open상태를 나타내었다. 또한 누출 경로가 완전 re-open된 후 나트륨 부위에서 시편의 self-wastage pattern은 온도에 영향을 받지 않음을 알 수 있었으며, 누출경로가 re-open 되면서 나타나는 defected 크기는 대략 5 mm 이내임을 알 수 있었다. 누출 경로가 완전 re-open 되는데 걸리는 시간은나트륨 온도가 높을수록 짧게 나타났으며, 평균적으로 $450^{\circ}C$에서 143분, $475^{\circ}C$의 경우 40.7분, $510^{\circ}C$의 경우 34.7분을 나타내었다.

• The Plant Pathology Journal
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• 제30권1호
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• pp.33-42
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• 2014

Nivalenol (NIV) and deoxynivalenol (DON) are predominant Fusarium-producing mycotoxins found in grains, which are mainly produced by Fusarium asiaticum and F. graminearum. NIV is found in most of cereals grown in Korea, but the genetic basis for NIV production by F. asiaticum has not been extensively explored. In this study, 12 genes belonging to the trichothecene biosynthetic gene cluster were compared at the transcriptional level between two NIV-producing F. asiaticum and four DON-producing F. graminearum strains. Chemical analysis revealed that time-course toxin production patterns over 14 days did not differ between NIV and DON strains, excluding F. asiaticum R308, which was a low NIV producer. Both quantitative real-time polymerase chain reaction and Northern analysis revealed that the majority of TRI gene transcripts peaked at day 2 in both NIV and DON producers, which is 2 days earlier than trichothecene accumulation in liquid medium. Comparison of the gene expression profiles identified an NIV-specific pattern in two transcription factor-encoding TRI genes (TRI6 and TRI10) and TRI101, which showed two gene expression peaks during both the early and late incubation periods. In addition, the amount of trichothecenes produced by both DON and NIV producers were correlated with the expression levels of TRI genes, regardless of the trichothecene chemotypes. Therefore, the reduced production of NIV by R308 compared to NIV or DON by the other strains may be attributable to the significantly lower expression levels of the TRI genes, which showed early expression patterns.

• 한국자동차공학회논문집
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• 제22권5호
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• pp.1-4
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• 2014

In recent years, requests for automotive seat comfort are increasing. An important issue of them is long-term seat comfort. Until now, the study for long-term seat comfort has been studied mainly using driver's questionnaire, changing adrenalin and electromyography. Actually the results and methodologies of them are difficult to apply to seat development and design because of money and time required. In this study, we developed Seating Feel Curve for seat comfort evaluation and a long-term seat comfort evaluation which can be applied to the development of seat comfort using seat support.