• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.1249-1250
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• 2005

• Bulletin of the Korean Chemical Society
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• v.7 no.6
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• pp.484-485
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• 1986

• Bulletin of the Korean Chemical Society
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• v.11 no.2
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• pp.109-114
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• 1990

The anionic transition metal hydrides $(HW(CO)_4P(OMe)_3\;^-,\;HW(CO)_5\;^-,\;HCr(CO)_5\;^-,\;HFe(CO)_4\;^-)$ react with transition metal alkyl $(CpMo(CO)_3(CH_3)$ to yield $CH_4\;and\;CH_3CHO$ in addition to the inorganic products $(CpMo(Co)_3\;^-$, etc.). The reaction of these anionic metal hydrides with CpMo(CO)3{CH2CH(CH2)2} may lead to an elucidation of the reaction mechanisms involved; the organic product distributions are among $CH_4,\;CH_2\;=\;CHCH_2CH_3$, and $CH_3CH(CH_2)_2$, depending upon the anionic metal hydride used. These anionic metal hydrides also are reported to undergo a hydride-halide exchange reaction with organic halides; therefore, these similar reactions have been compared in terms of leaving group ability $(CpMo(CO)_3\;^-\;vs.\;Br^-)$ and the mechanistic pathways.

• Nuclear Engineering and Technology
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• v.55 no.1
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• pp.119-130
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• 2023

Among the various elements of probabilistic safety assessment (PSA), human failure events (HFEs) and their dependencies are major contributors to the quantification of risk of a nuclear power plant. Currently, the dependency among HFEs is reflected using a post-processing method in PSA, wherein several drawbacks, such as limited propagation of minimal cutsets through the fault tree and improper truncation of minimal cutsets exist. In this paper, we propose a method to model the HFE dependency directly in a fault tree using the if-then-else logic. The proposed method proved to be equivalent to the conventional post-processing method while addressing the drawbacks of the latter. We also developed a software tool to facilitate the implementation of the proposed method considering the need for modeling the dependency between multiple HFEs. We applied the proposed method to a specific case to demonstrate the drawbacks of the conventional post-processing method and the advantages of the proposed method. When applied appropriately under specific conditions, the direct fault-tree modeling of HFE dependency enhances the accuracy of the risk quantification and facilitates the analysis of minimal cutsets.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.7
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• pp.625-638
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• 2014

In this study, the uncertainties in the critical flow functions (CFFs) calculated by the AGA8-dc equation of state were estimated. To this end, the formulas for enthalpy, entropy, and speed of sound, which are used in calculating the CFF, were expressed in the form of dimensionless Helmholtz free energy and its derivatives, and the uncertainty in Helmholtz free energy was inferred. To consider the variations in the compressibility-dependent variables induced by the variation (i.e., uncertainty) in compressibility, the form of the AGA8-dc equation was modified to have a deviation equal to the uncertainty under each flow condition. For each independent uncertainty component of the CFF, a model for uncertainty contribution was developed. All these changes were applied to GASSOLVER, which is KOGAS's thermodynamic database. As a result, the uncertainties in the CFF were estimated to be 0.025, 0.055, and 0.112 % at 10, 50, and 100 bar, respectively, and are seen to increase with the increase in pressure. Furthermore, these results could explain the deviations in the CFFs across the different labs in which the CFF international comparison test was conducted under the ISO management in 1999.

• Health Policy and Management
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• v.14 no.3
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• pp.97-121
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• 2004

Recently, human embryonic stem cell research raises exciting public expectation on medical possibilities as well as ethical debate. Embryo management has become an integral part of the management of infertility treatment, researches on embryo and human embryonic stem cells and so on. Britain has permitted the research on stem cells derived from human embryo which made the first nation to allow the cloning of human embryo for the stem cell research. However, new technologies such as the assisted reproductive technologies and human embryonic stem cell research continue to pose an increasing source of ethical dilemmas for physician, scientists, legislators, religious authorities and the general publics to deal with. None the less, the United Kingdom has adopted the most liberal policies regarding human embryo and human embryonic stem cell research. The implication of the British embryo management system are as follows: 1) the development of reproductive technologies and new stem cell research technologies continue to pose legal and ethical debates, since those involve several parties; 2) the UK has taken the legal and institutional approaches to cope with those serious issues; 3) the UK adopted most liberal policies regarding embryonic and human embryonic stem cell researches; 4) the British HFE Act is consistent with the existing Acts related to human embryo management and researches; 5) through amending the HFE Act to accomodate the changes of technologies, the UK try to minimize the legal and ethical burden on undertaking research regarding embryo. The debates about the researches on human embryo and human embryonic stem cells is likely to continue in the Korean society. Because of the controversy and competing ethical values, as well as the evolving technologies, so far no consensus exists in our society. It suggest that it is premature to bring closure by ruling out any particular approaches. Thus our society needs to make an efforts to find a basis which could resolve the societal controversies through enriching the societal conversation about the profound ethical issues regarding embryo management.

• Korean Journal of Community Nutrition
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• v.20 no.4
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• pp.273-280
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• 2015

Objectives: The study aimed to examine whether healthy diet score was associated with stress and social support among 472 Chinese college students in Korea. Methods: The study participants were 472 (187 male, 285 female) Chinese college students in Gyeong-gi area. From April 2013 to Oct 2013, participants were asked to fill out questionnaires on healthy diet score (20 questions), stress (20 questions), and social support (20 questions). Each question was scored by a 5-point Likert scale (total scores of each questionnaire were ranged from 20 to 100). Questions on healthy diet were sub-categorized as 'Healthy food eating (HFE)', 'Healthy eating habits (HEH)', and 'Avoidance of unhealthy food (AUF)'. Reliability test was conducted with Cronbach's ${\alpha}lpha$ (${\alpha}=0.79$). Results: Healthy diet score was higher in participants who stayed longer in Korea, who spoke Korean language fluently, and who assessed his or her own health status as very good. Adjusted means of healthy diet scores were estimated after adjusting for age, gender, body mass index, duration of staying, and Korean language fluency. According to tertile categories, participants with low tertile stress but high tertile social support showed the highest score of healthy diet ($72.59{\pm}1.45$), whereas participants with high tertile of stress but low tertile of social support had the lowest score of healthy diet ($59.22{\pm}1.54$). As for the three sub-categories of healthy diet score, the score of HFE increased as the score of social support increased. Conclusions: Our findings suggested that social support system is beneficial to alleviate stress and to improve healthy diet score.

• Applied Chemistry for Engineering
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• v.4 no.1
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• pp.144-152
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• 1993

Immobilized polyethylene glycols onto metal oxides such as ${\gamma}-Al_2O_3$, ${\alpha}-Al_2O_3$, $SiO_2$ and $TiO_2$ were used as phase transfer catalysts for the room temperature synthesis of aniline from nitrobenzene and ironpentacarbonyl. The amount of attached PEG molecules increased with specific surface area of metal oxides. Among the immobilized catalysts tested PEG/${\gamma}-Al_2O_3$ showed the highest activity. The reaction rate increased with the chain length of PEG mole-cules and the aqueous NaOH concentration. Mechanistic study carried out using infrared spectrometer revealed that the role of PEG was to increase the formation of $HFe(CO)_4{^-}$ ion, which is known as active species, and its movement from aqueous to organic phase.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.15-21
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• 2009

Objectives : This study was designed to investigate the effect of water extract from Paeonia Lactiflora Pasll. with medicinal herb on plasma lipid and glucose in rats fed high fat diet. Methods : Experimental groups were divided into control diet group(C), high fat diet group(HF), high fat diet and 5% water extracts from Paeonia Lactiflora Pasll. with medicinal herb group(HFE I), high fat diet and 10% water extract from Paeonia Lactiflora Pasll. with medicinal herb group(HFE II). Weight gain, food intake, food efficiency, plasma lipid concentration and glucose were determined for 10 weeks during high fat diet. Results : In this experiment, body weight and food efficiency were significantly increase in high fat diet. High fat diet group showed elevated levels of total cholesterol, LDL-cholesterol and free fatty acid. Consumption of 10% water extract Paeonia Lactiflora Pasll. with medicinal herb lowers level of total cholesterol, LDL-cholesterol and free fatty acid. But levels of plasma triglyceride, HDL-cholesterol and glucose did not affect by high fat diet and water extract Paeonia Lactiflora Pasll. with medicinal herb Conclusions : In these results, water extract Paeonia Lactiflora Pasll. with medicinal herb in high fat diet group decreased plasma total cholesterol, LDL-cholesterol and free fatty acid. Thus the Paeonia Lactiflora Pasll. with medicinal herb might be useful in the treatment of hyperlipemia.

• Special Issue of the Society of Naval Architects of Korea
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• 2017.10a
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• pp.46-53
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• 2017

We work for big offshore project in the Korean shipyards as a EPC contract. There are a lot of risks even though the FEED Engineering was taken in the famous engineering company. In case of ICHTHYS CPF, it worked on the FEED activity for several years. Here is mention that design modification was carried how to modify material and specification according to shipyards human resource and yard practice for your reference. Furthermore, I expect that this paper is used for Korean engineer for their reference.