• Journal of Radiation Protection and Research
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• 제47권2호
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• pp.77-85
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• 2022

Background: After the Fukushima Daiichi Nuclear Power Station (FDNPS) accident, a model was developed to estimate the external exposure doses for residents who were expected to return to their homes after evacuation orders were lifted. However, the model's accuracy and uncertainties in parameters used to estimate external doses have not been evaluated. Materials and Methods: The model estimates effective doses based on the integrated ambient dose equivalent (H^*(10)) and life patterns, considering a dose reduction factor to estimate the indoor H^*(10) and a conversion factor from H^*(10) to the effective dose. Because personal dose equivalent (H_p(10)) has been reported to agree well with the effective dose after the FDNPS accident, this study validates the model's accuracy by comparing the estimated effective doses with H_p(10). The H_p(10) and life pattern data were collected for 36 adult participants who lived or worked near the FDNPS in 2019. Results and Discussion: The estimated effective doses correlated significantly with H_p(10); however, the estimated effective doses were lower than H_p(10) for indoor sites. A comparison with the measured indoor H^*(10) showed that the estimated indoor H^*(10) was not underestimated. However, the H_p(10) to H^*(10) ratio indoors, which corresponds to the practical conversion factor from H^*(10) to the effective dose, was significantly larger than the same ratio outdoors, meaning that the conversion factor of 0.6 is not appropriate for indoors due to the changes in irradiation geometry and gamma spectra. This could have led to a lower effective dose than H_p(10). Conclusion: The estimated effective doses correlated significantly with H_p(10), demonstrating the model's applicability for effective dose estimation. However, the lower value of the effective dose indoors could be because the conversion factor did not reflect the actual environment.

• 가정과삶의질연구
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• 제27권2호
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• pp.203-211
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• 2009

This study was conducted to evaluate a forecast model designed to describe a vocational high school for runaway students. The study included 2000 adolescents from the KEEP(Korean Education and Employment Panel). A Data mining decision tree model revealed that: (1) Suicide ideation was a risk factor for running away among smokers. (2) High self-evaluation was a risk factor for running away among individuals that smoked and had no suicide ideation. (3) Drinking was predicted as a risk factor for no smokers, while family life dissatisfaction was predicted as a risk factor among non-smokers that drank. (4) Negative relationship with mother was predicted as a risk factor among non-drinking non-smoking.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.499-500
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• 2008

In this paper, we design and implement the monolithic power factor correction IC for system power modules using a high voltage(50V) CMOS process. The power factor correction IC is designed for power applications, such as refrigerator, air-conditioner, etc. It includes low voltage logic, 5V regulator, analog control circuit, high-voltage high current output drivers, and several protection circuits. And also, the designed IC has standby detection function which detects the output power of the converter stage and generates system down signal when load device is under the standby condition. The simulation and experimental results show that the designed IC acts properly as power factor correction IC with efficient protective functions.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.519-520
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• 2008

In this paper, we design and implement the monolithic zero crossing detection power factor correction IC using a high voltage 30V BCD process. The ZCD PFC IC is designed for power applications, such as notebook, LCD monitor, etc. It includes power factor correction function and several protection circuit, regulator, high-voltage high current output drivers. And also, the designed IC has restart timer function which the output pulse is generated if the output signal of IC is not in a 200us. The simulation results show that the designed IC acts properly as power factor correction IC with efficient protective functions.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.108-109
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• 2005

The aim of Port State Control(PSC) system is recognized as a proficient mechanism in preventing coastal traffic accident and protecting marine environment. Recently, PSC system is focused on human factor of International Maritime Convention, especially ILO and STCW Convention by considering many accidents resulted from human factor. Therefore, we have to understand of Consolidated Maritime Labour Convention which describes employment conditions and social welfare policy, the rights about the lowest wages, the overdue wages, the unemployment protection. a disaster reward, etc and STCW Convention which describes standards of training, certification and watchkeeping for seafarers. The aim of this study is to recognize inspection points about human factor of these Conventions. .

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2007년도 추계학술대회
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• pp.107-119
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• 2007

The purpose of this article is to examine the relationship between unsafe behavior, human factor and human error. For the object, several correlation analyses for those three elements were implemented. Several hypotheses for the relationship between them was suggested. The suggested hypotheses were verified by a comprehensive survey received from 132 safety manager of manufacturing industry. The conclusions were proven from the hypotheses verificaiton as belows; 1) The dependent relation items between unsafe behavior and human factor are dress protection tool, machine(equipment) and working rule have a dependent relation. 2) The dependent relation items between human factor and human error are uncommunication, control, slaps, fatigue, education, system, unmonitoring, failure. 3) The dependent relation items between human error and unsfafe behavior are decline and product/working method,failure and uncommunication have a dependent relation.

• Journal of Electrical Engineering and Technology
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• 제8권1호
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• pp.64-69
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• 2013

For power system protection, the distance relay settings are important. Apparent factor is a necessary parameter in distance relay settings. Apparent factors have to be calculated when setting the distance relays and doing the resetting in case of configuration change in power system. The problem is that the current method to calculate apparent factor requires tools and plenty of time to do fault analysis and this method is complex especially in case of configuration change. Therefore this paper proposes a fast algorithm to calculate apparent factor without the fault analysis. Test results prove that this algorithm is simple and accurate by simulation.

• 한국패류학회지
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• 제30권4호
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• pp.371-381
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• 2014

The bioaccumulation of 16 United States Environmental Protection Agency (USEPA) priority polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs in the Manila clam, Ruditapes philippinarum exposed to sediments artificially contaminated by Iranian Heavy Crude Oil was measured and the biota-sediment accumulation factor (BSAF) was estimated through laboratory experiments. The proportion of 16 PAHs accumulated in the tissue of R. philippinarum was only from 3 to 7% of total PAHs. Among 16 PAHs, the concentration of naphthalene was highest in the tissue. Alkylated PAHs were highly accumulated more than 93% of total PAHs. The C3 dibenzothiophene was most highly accumulated. The relative composition of alkylated naphthalenes in the tissue of R. philippinarum was lower than in the sediments. In contrast, those of alkylated compounds of fluorenes, phenanthrenes, dibenzothiophenes were higher in the tissue than the sediments. The BSAF for sum of 16 PAHs was 0.11 to 0.13 g carbon/g lipid and that for alkylated PAHs was 0.05 to 0.06 g carbon/g lipid. Naphthalene showed the highest BSAF value. Alkylated PAHs with the same parent compound, BSAF tended to increase with the number of alkylated branch increased, except for alkylated chrysenes. BSAF of total PAHs lies between that of field-based values, and are also similar to those of other persistent organic pollutants (PCBs, DDTs, HCHs). This study provides the BSAF values of individual alkylated PAHs accumulated in R. philippinarum for the first time and will be used as a basis for further understanding the bioaccumulation of organic contaminants in the marine benthic organisms.

• 한국균학회지
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• 제45권1호
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• pp.74-82
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• 2017

꽃도라지(Eustoma grandiflorum)는 국내에서 장식용 화훼류로 널리 이용되는 절화류이다. 2015년 경기도 여주와 경남 김해 지역에서 꽃도라지가 시들고, 지제부가 잘록해지면서 위축되고, 뿌리가 썩는 증상이 나타났다. 병든 식물체는 포장이나 육묘상자에서 황화되고, 뿌리 발육이 저해되었고, 진전되면 전체적으로 황화되면서 시들고, 위축되며, 결국 2~3개월 안에 완전히 말라 죽는다. 병든 식물체 지제부에서 Fusarium균이 분리되었고, 9개 균주를 단포자 분리하여 형태적 특성을 조사한 결과, Fusarium solani로 동정되었다. 대형포자는 통통하고, 직선형이거나 약간 굽은 초승달 모양이고, 소형분생포자는 긴mono형태의 분생포자원세포에서 false head상으로 형성되었다. 후벽포자는 균사 중간 혹은 끝부분에 풍부하게 형성되었다. 이와 같은 동정 결과는 translation elongation factor 1 alpha (TEF)와 RNA polymerase II subunit (RPB2) 유전자의 염기서열 분석으로 재확인되었다. 그 결과, 분리 균주는 NCBI GenBank에 등록된 F. solani와 TEF 유전자는 99.2~99.9%, RPB2 유전자는 98.0~98.1%의 상동성을 나타내었다. 건전한 꽃도라지 유묘의 뿌리를 포자현탁액에 침지 접종하여 병원성 검정을 수행한 결과, 접종 7일 이내에 접종한 식물체에서만 병징이 관찰되었다. 따라서 이 병을 F. solani에 의한 꽃도라지 뿌리썩음병으로 명명하며, 병의 발생을 국내에서 처음으로 보고한다.

• 한국염색가공학회지
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• 제23권3호
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• pp.187-194
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• 2011

This study used Jeju scoria to dye cotton fabric and measured its dyeability, colorfastness, antibacterial activity, deodorization efficiency, ultraviolet protection, and far-infrared emission. The cotton fabric was colored to yellowish red and optimal dyeing can be achieved at a temperature of $80^{\circ}C$ for a dyeing time of 120 minutes with a colorant concentration of 25%(o.w.b). The colorfastness to light, rubbing, perspiration, and washing was 8, 5, 5, and 4~5 ratings respectively, where the wash colorfastness remained after 15 wash cycles. The cotton fabric dyed with Jeju scoria demonstrated excellent antimicrobial activity to Staphylococcus aureus and high deodorization efficiency. Ultraviolet protection factor was as high as 50+. The Jeju scoria can be used as a new colorant for the natural dyeing of silk.