• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.99-100
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• 2004

AMBIDEXTER-NEC의 천이노심은 $^{Nat}Th$과 $^{Nat}U$의 주입만으로 전 출력의 Break-even 노심에 도달하기위한 중간 단계이다. 선행연구에서 수행한 전 출력노심인 평형노심의 핵종수밀도에 도달하기 위해서 평형노심에서의 기저물질, 잠재핵분열성물질, 핵분열물질의 수밀도를 각 SEU-기반, Pu-기반, ADS-기반에서 그대로 유지하여 초기노심을 구성하였다. 또 각 시나리오에 대해 최대첨두출력과 원자로의 안전성을 고려해 Excess Reactivity를 5mk 내에서 초기노심을 결정하였다. 각 노심은 주 핵분열성물질 $^{235}U$, $^{239}Pu$ 및 $^{233}U$의 핵반응단면적 특성에 따라 평균 전환율이 각각 0.95, 0.83 및 1 .21 로서 핵연료물질의 적절한 선택만으로도 전환로, 연소로 및 증식로로 설계할 수 있음을 보여준다. 이러한 $Th/^{233}U$, U/Pu 핵연료주기를 사용하는 AMBIDEXTER-NEC 용융염핵연료 원자로의 초기노심에서 시작한 천이노심은 평형노심에장전할 충분한 $^{233}U$ 양을 확보해야 하므로 천이노심의 목표는 평형노심 $^{233}U$의 요구량에 최소한의 기간에 가장 적은 외부주입을 통해 도달하는 것이다. 천이노심에서 임계가 유지되는 AMBIDEXTER-NEC 원자로시스템의 3군 핵종변환 코드인 HELIOS-SQUID-AMBIBURN 체제를 개발하였고 그림 1.에 나타내었다. 이 알고리즘은 각 초기노심 중원소의 미시단면적, 중원소를 제외한 원소들의 거시단면적, 임계도를 만족하는 중성자속 및 외부주입율을 계산하여 SQUID 및 AMBIBURN 입력자료를 제공한다. 또한 일정시간 중원소의 핵종농도, 외부주입율과 중성자속이 일정하다는 가정 하 에 반복수행 하고 SEU-기반과 Pu-기반의 경우에는 각각 핵변환을 거쳐 재순환되는 $^{233}U$ 및 $^{239}Pu$의 양을 바로 주입하는 최대재순환 경우와 평형노심 요구 장전량에 이를 때까지 시설 내 저장하는 최소재순환 경우로 상황을 모사하였다. 그림 2 는 각 시나리오별 초기노심에서부터 200FPD까지 단위 용융염 체적당 $^{233}U$의 수밀도 시간변화를 나타낸 것이다. 그림을 보면 50일 이후부터는 수밀도의 변화가 일정한 기울기를 보이고 있고 재처리공정에서 $^{233}Pa$를 분리하는 최소재순환의 경우에는 최대재순환보다 2-3%정도에 지나지않아 그림에서 나타내지않았다. SEU-기반 및 Pu-기반에서 $^{233}U$의 증가율이 각각 2.54E+13, 2.81E+13 #/cc/d 로 Pu 기반이 조금 더 큰 증가율을 나타내고 있지만 평형노심 농도 1.04E+20 #/cc/d 에 도달하기 위해서는 두 경우 모두 매우 긴 시간이 걸릴 것을 예상할 수 있다. 요컨대 250MWth AMBIDEXTER-NEC가 평형노심을 이루기 위해 필요로 하는 $^{233}U$을 생산하는데 제안한 SEU-기반, Pu-기반 시나리오는 천이노심주기기간이 전형적인 원자로 수명 3-40년 보다 매우 큰 것으로 나타났다. 따라서 장전될 $^{233}U$의 확보를 위한 최적옵션은 초기노심부터 ADS와 같은 외부생산시설로부터 전량을 공급 받아 운전하는 것이라 판단된다.

• Journal of Korean Academy of Nursing
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• v.50 no.1
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• pp.66-80
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• 2020

Purpose: This study aims to examine the effects of nursing interventions based on the Extended Theory of Planned Behavior (ETPB) regarding self-efficacy for exercise (SEE), physical activity (PA), physical function (PF), and quality of life (QOL) in patients with lung cancer who have undergone pulmonary resection. Methods: This quasi-experimental study was conducted between July 2015 and June 2018 in two university-affiliated hospitals. The intervention included pre-operative patient education, goal setting (action and coping planning), and feedback (behavior intention and perceived behavioral control). The intervention group (IG) (n=51) received nursing interventions from the day before surgery to 12 months after lung resection, while the comparison group (CG) (n=36) received usual care. SEE, PA, PF (dyspnea, functional status, and 6-minute walking distance [6MWD]), and QOL were measured before surgery and at one, three, six, and 12 months after surgery. Data were analyzed using the χ² test, Fisher's exact test, Mann-Whitney U test, t-test, and generalized estimation equations (GEE). Results: There were significant differences between the two groups regarding SEE (χ²=13.53, p=.009), PA (χ²=9.51, p=.049), functional status (χ²=10.55, p=.032), and 6MWD (χ²=15.62, p=.004). Although there were no time or group effects, the QOL mental component (Z=-2.78, p=.005) of the IG was higher than that of the CG one month after surgery. Interventions did not affect dyspnea or the QOL physical component. Conclusion: The intervention of this study was effective in improving SEE, PA, functional status, and 6MWD of lung cancer patients after lung resection. Further extended investigations that utilize ETPB are warranted to confirm these results.

• International Area Studies Review
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• v.16 no.1
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• pp.29-52
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• 2012

This study investigates the relationship between corporate social responsibility and corporate governance among major US corporations belonging to S&P 500 index during 2000-2008. Specifically, it examines the ways in which firms engage their boards of directors in integrated strategy by establishing a public affairs(PA) or social responsibility(SR) committee at the board level and the effects of this practice on their corporate social performance(CSP). The empirical findings show that negative CSP is the major driver for establishing such a committee, that is, firms suffering from negative CSP as a result of experiencing undesirable social events tend to establish such a committee. On the other hand, such a committee helps the firm increase positive CSP once it is established. In other words, the purpose of establishing such board-level committees is to address problems associated with negative CSP, and once established, they can help enhance positive CSP by enabling the firm to integrate market, non-market, and social responsibility aspects in strategy formulation more effectively. This is evidence that Baron's integrated strategy framework can help firms achieve tangible outcomes.

• Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.25.1-25.8
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• 2016

The fractionation of serine protease inhibitor (SPI) from fish roe extracts was carried out using polyethylene glycol-4000 (PEG4000) precipitation. The protease inhibitory activity of extracts and PEG fractions from Alaska pollock (AP), bastard halibut (BH), skipjack tuna (ST), and yellowfin tuna (YT) roes were determined against target proteases. All of the roe extracts showed inhibitory activity toward bromelain (BR), chymotrypsin (CH), trypsin (TR), papain-EDTA (PED), and alcalase (AL) as target proteases. PEG fractions, which have positive inhibitory activity and high recovery (%), were the PEG1 fraction (0-5 %, w/v) against cysteine proteases (BR and PA) and the PEG4 fraction (20-40 %, w/v) against serine proteases (CH and TR). The strongest specific inhibitory activity toward CH and TR of PEG4 fractions was AP (9278 and 1170 U/mg) followed by ST (6687 and 2064 U/mg), YT (3951 and 1536 U/mg), and BH (538 and 98 U/mg). The inhibitory activity of serine protease in extracts and PEG fractions from fish roe was stronger than that of cysteine protease toward common casein substrate. Therefore, SPI is mainly distributed in fish roe and PEG fractionation effectively isolated the SPI from fish roes.

• Animal cells and systems
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• v.6 no.2
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• pp.167-170
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• 2002

The long terminal repeats (LTRs) of human endogenous retrovirus (HERV) have been found to be coexpressed with sequences of closely located genes. It has been suggested that the LTR elements have contributed to the structural change or genetic variation of human genome connected to various diseases and evolution. We examined the HERV-W LTR elements in various cancer cells (2F7, A43l , A549, HepG2, MIA-PaCa-2, PC-3, RT4, SiHa, U-937, and UO-31). Using genomic DNA from the cancer cells, we performed PCR amplification and identified twelve new HERV-W LTR elements. Those LTR elements showed a high degree of sequence similarity (88-99％) with HERV-W LTR (AF072500). A phylogenetic tree obtained by the neighbor-joining method revealed that HERV-W LTR elements could be mainly divided into two groups through evolutionary divergence. Three HERV-W LTR elements (RT4-2, A43l-1, and UO3l-2) belonged to Group 1, whereas nine LTR elements (2F7-2, A549-1, A549-3, HepG2-3, MP2-2, PC3-1, SiHa-8, SiHa-10, and U937-1) belonged to Group 11. Taken together, our new sequence data of the HERV-W LTR elements may contribute to an understanding of tissue-specific cancer by genomic instability of LTR integration.

• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.582-587
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• 2011

Holdup characteristics of bubble, wake and continuous liquid phases were investigated in bubble columns with viscous liquid media. Effects of column diameter(0.051, 0.076, 0.102 and 0.152 m ID), gas velocity($U_G$=0.02~0.16 m/s) and liquid viscosity(${\mu}_L$=0.001~0.050 $Pa{\cdot}s$) of continuous liquid media on the holdups of bubble, wake and continuous liquid phases were discussed. The three phase such as bubble, wake and continuous liquid phases were classified successfully by adapting the dual electrical resistivity probe method. Compressed filtered air and water or aqueous solutions of CMC(Carboxy Methyl Cellulose) were used as a gas and a liquid phase, respectively. To detect the wake as well as bubble phases in the bubble column continuously, a data acquisition system(DT 2805 Lab Card) with personal computer was used. The analog signals obtained from the probe circuit were processed to produce the digital data, from which the wake phase was detected behind the multi-bubbles as well as single bubbles rising in the bubble columns. The holdup of bubble and wake phases decreased but that of continuous liquid media increased, with an increase in the column diameter or liquid viscosity. However, the holdup of bubble and wake phases increased but that of continuous media decreased with an increase in the gas velocity. The holdup ratio of wake to wake to bubble phase decreased with an increase in the column diameter or gas velocity, however, increased with an increase in the viscosity of con-tinuous liquid media. The holdups of bubble, wake and continuous liquid media could be correlated in terms of operating variables within this experimental conditions as: ${\varepsilon}_B=0.043D^{-0.18}U_G^{0.56}{\mu}_L^{-0.13}$, ${\varepsilon}_W=0.003D^{-0.85}U_G^{0.46}{\mu}_L^{-0.10}$, ${\varepsilon}_C=1.179D^{0.09}U_G^{-0.13}{\mu}_L^{0.04}$.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.302-306
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• 2000

인터넷의 발전과 함께 많은 성장을 하고 있는 멀티미디어 응용서비스의 중의 하나인 인터넷폰은 PSTN이 아닌 인터넷의 U(Internet protocol)을 통해 전화와 관련된 기능을 구현하는 일련의 통신서비스 기술로서 인터넷을 이용하여 음성을 전달하기 위한 기술이 요구된다. 그리고 인터넷폰 시스템은 통화하고자 하는 착발신 단말의 종류에 따라 PC-to-PC, PC-to-Phone, Phone-to-PC 인터넷폰 시스템으로 구분되어 질 수 있다. 본 논문에서는 우선 사내 전화교환기인 사설교환기(PABX) 없이 동일한 UM 상의 임의의 두 PC간의 통신과 서로 다른 MU 상의 임의의 두 PC간에 통신이 가능하도록 PC-to-PC 인터넷폰 시스템의 호제어 메시지 처리, 상태전이도 등의 교환기 및 단말기 시스템의 설계 및 구현에 관해 연구하였다. 향후 PC-to-Phone과 Phone-to-PC 인터넷폰 시스템에 관한 연구를 지속적으로 수행할 것이다.

• Journal of Ginseng Research
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• v.22 no.3
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• pp.216-221
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• 1998

We examined the anti-invasive activity of ginsenosides Rhl, Rha on the highly metastatic HT1080 human fibrosarcoma cell line. In vitro invasion assay showed ginsenoside Rhr reduced tumor cell invasion through a reconstituted basement membrane in a transwell chamber more than ginsenoside Rh1. Significant down-regulation of matrix metalloproteinase-9 (MMP-9) by ginsenosides Rh, and Rh2 was detected by Northern blot analysis. However, the expression of MMP-2 was not affected by Rh, and Rhr. The expression of tissue inhibitor of metalloproteinase-2 (TIMP-2) was increased by Rhl after 0.5, 1 or 3 day-treatment but reduced after 6 day-treatment. However, the expression of TIMP-2 was not changed by treatment with Rh2. Plasminogen activator inhibitor (PAI) and urokinase-type plasmlnogen activator (uPA) were not changed by treatment with Rh1 and Rh2 for 3 and 6 days. Quantitative gelatin-based zymography confirmed a markedly reduced expression of MMP-9 but MMP-2 after treatments with ginsenosides Rhl and Rha. These results suggest that down-regulation of MMP-9 contributes to the anti-invasive activity of ginsenosides Rhl and Rhr in the HT1080 cells.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.58-63
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• 1998

AMBIDEXTER(Advanced Molten-Salt Break even Inherently-Safe Dual-Mission EXperiment & TEst Reactor)는 토륨-우라늄 연료주기의 핵적자활성 요건을 설계하는 방법으로써 핵분열중간 생성물인 $^{233}$ Pa의 시간격리, 노내 방사성물질 농도저감, 잉여반응도 및 증식률향상을 위해 핵분열 생성물질의 온라인 정화.처리.재생 개념을 채택하고 있다. 본 연구에서는 AMBIDEXTER 로심의 핵분열성물질의 연소와 온라인 정화.처리에 따른 핵연료내 원소분포 변화를 기술하기 위해 핵분열생성물질의 평형포화농도에 대응하는 등가연소도(Equivalent Burnup)를 정의하고 이를 노심의 핵적자활성 요건에 대해 최적화하는 핵연료 정화공정의 시간상수 특성을 시뮬레이션 하였다. 핵분열생성물질농도의 동특성은 ORIGEN2 코드에 내장된 연속재처리 모델을 이용하여 해석하였으며 실용화가 입증된 후보정화공정들을 고려하여 모든 핵종을 5종의 핵종군으로 분류하여 평가하였다. 시뮬레이션 결과 유효정화주기를 0.1 (노심장전량/일)로 연속재처리 할 때 노심내 포화등 가연소도는 약 650 (MWD/TeH.E.)로 대응되며 이때 동일한 핵연료량으로부터 생성된 노내 핵분 열생성물질 평형농도는 최대연소도 33000MWD/TeU의 PWR 평형노심 BOC시의 대비해 약 1/10 에 해당하는 양이 잔유하는 것으로 나타났다.

• Journal of the Korean Solar Energy Society
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• v.25 no.4
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• pp.61-67
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• 2005

The purpose of this study is to evaluate the air tightness of Zero Energy Solar House(ZeSH) and to propose the construction improvement of junctions and penetrations where air infiltration was identified. Air leakage rate were measured by means of blower door test in accordance with ASTM E779-87. The results showed that ZeSH has an excellent airtightness with ACH50/20 (air change per hour at a pressure difference of 50 Pa between inside outside) of 0.34hr-1 and leakage class E by normalized leakage area of ASHRAE.