• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.5
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• pp.225-233
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• 2001

SIME(SIngle Machine Equivalent) method has been recognized as a useful tool to determine transient stability of power systems. In this paper, SIME method is used to develop the KEPCO transient stability assessment (TSA) tool. A new screening algorithm that can be implemented in SIME method is proposed. The salient feature of the proposed screening algorithm is as follows. First, critical generators are identified by a new index in the early stage of the time domain simulation. Thus, computational time required to find OMIB(One Machine Infinite Bus) can be reduced significantly. Second, clustering critical machines can be performed even in very stable cases. It enables to be avoid extra calculation of time trajectory that is needed in SIME for classifying the stable cases. Finally, using power-angle trajectory and subdividing contingency classification have improved the screening capability. This algorithm is applied to the fast TSA of the KEPCO system.

• Nuclear Engineering and Technology
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• v.50 no.8
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• pp.1234-1245
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• 2018

The risk of multi-unit nuclear power plants (NPPs) at a site has received considerable critical attention recently. However, current probabilistic safety assessment (PSA) procedures and computer code do not support multi-unit PSA because the traditional PSA structure is mostly used for the quantification of single-unit NPP risk. In this study, the main purpose is to develop a multi-unit Level 2 PSA method and apply it to full-power operating six-unit OPR1000. Multi-unit Level 2 PSA method consists of three steps: (1) development of single-unit Level 2 PSA; (2) extracting the mapping data from plant damage state to source term category; and (3) combining multi-unit Level 1 PSA results and mapping fractions. By applying developed multi-unit Level 2 PSA method into six-unit OPR1000, site containment failure probabilities in case of loss of ultimate heat sink, loss of off-site power, tsunami, and seismic event were quantified.

• Journal of Korean Dental Hygiene Science
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• v.4 no.1
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• pp.53-64
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• 2021

Background: The elderly in long-term care facilities tend to have a diminished oral health status, with a high prevalence of dental caries and periodontal disease, as reduced cognitive function, joint mobility, and gait ability hinder the performance of oral hygiene. To improve the oral health of the elderly at long-term care facilities, it is necessary to have precise guidelines for oral health care and assessment; however, such guidelines are not readily available. Therefore, the present study aimed to develop an oral care assessment tool with verified reliability and validity. Methods: The participants in this study were 100 elderly patients at a care facilities and 10 clinical dental hygienists. Collected data were analyzed using the descriptive statistics, content validity index, and inter-rater reliability, as well as the analyses of intra-class correlation coefficient. Results: After a review of relevant literature, a preliminary questionnaire comprised of seven questions related to the evaluation of oral health was formed. After revising and supplementing the questions through a content validity test, a total of nine questions were selected. Conclusion: The novel assessment tool developed for the present study is anticipated to allow analyses of the level of problems related to oral health care before routine and professional care. Moreover, regular oral health status check-ups will enable the early diagnosis and treatment of diseases.

• Korean Journal of Human Ecology
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• v.23 no.5
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• pp.807-823
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• 2014

The purpose of this study is to verify the effects of storytelling-centered arts educational activities based on the famous painting appreciation on young children's appreciation ability of pictures and creativity. The study was conducted with a total of 50 5-year-old young children in two classes of B Day Care Center in the city of J, Jeollabukdo. The children were randomly divided into an experimental group(25) and a control group(25). The storytelling-centered arts educational activities based on the famous painting appreciation was conducted for the experimental group for 12 weeks from April 29, 2013 to July 19, 2013. The activities were composed of 3 steps of 'appreciation-expression-exhibition & assessment' on the basis of 2-week basic units. The appreciation activities were composed basing upon the types of the famous painting appreciation and storytelling, and expression and exhibition & assessment activities were composed of 4 areas of arts(music/movement/language/art). The results of the study are as follows. First, the storytelling-centered arts educational activities based on the famous painting appreciation generally improved young children's painting appreciation abilities in all sub-areas(observation and description/artist's intention of subject expression/mood of a work/material and technique/artistic factors/attitude to the work). Second, the storytelling-centered arts educational activities based on the famous painting appreciation generally improved young children's creativities in all sub-areas(originality/fluency/flexibility/imagination).

• Environmental Analysis Health and Toxicology
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• v.20 no.2 s.49
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• pp.179-186
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• 2005

Particulate materials (PM) less than 10 ${\mu}m$ in diameter are of special interest in air pollution because they are respirable and responsible for the increasing mortality rate of lung cancer and cardiovascular diseases. These particles are often referred to as $PM_{10}$ and they are divided into a coarse fraction and a fine fraction which is also often referred to as $PM_{25}$. In this study, we monitored the TSP, $PM_{10},\;PM_{2.5}$ concentration of ambient air collected in northern part of Seoul in early spring and measured the concentration of heavy metals; Cr, Mn, Zn, As, Cd, and Pb. All the heavy metals were found in the collected particles and the concentrations were variable in the $PM_{10},\;and\;PM_{2.5}$ respectively. The detected concentration ranges were Cr: $ND\~2,889ng/m^3,\;Mn:2.4\~257.9ng/m^3,\;Zn:ND\~353.7ng/m^3,\; As:ND\~22.3ng/m^3,\;Cd:0.1\~2.9ng/m^3,\;and\;Pb:ND\~392.2ng/m^3$ in fine particles. Heavy metal toxicity of the particles were also tested in $H_9C_2$ cell line derived from rat cardiomyocytes. As for the results of health risk assessment calculated by unit risk of IRIS, heavy metals in ambient air of Seoul metropolitan area were found to be responsible for the increase of total excess cancer risk. Among them, chromium (hexavalent) was found to be the most risky in fine particles of ambient air collected in the northern part of Seoul in early spring.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.565-571
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• 2017

The purpose of this study is to determine the effects of error sources in emotional intelligence assessment of young children. The emotional intelligence of 198 five years old children was assessed using the Emotional Intelligence Scale developed by Lee[14]. Evaluation results were analyzed using G study for generalizability theory. G study results show that parents can be effective evaluators for emotional intelligence in young children. Strategies to reduce error effects are discussed.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1737-1742
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• 2013

Early diagnosis has a major role in improving prognosis of breast cancer. The purpose of this study was to assess the risk status of women 35-69 years of age using risk assessment models and the prevalence of mammography in a community setting. The sample of this cross sectional study consisted of 227 women, 35-69 years of age residing in Izmir, a city located in western region of Turkey. A questionnaire was used to collect data and the Gail and Cuzick-Tyrer models were applied to assess the risk of breast cancer. In this study, 52.7% of women had mammography at least once, and 41.3% of the women over the age of 40 had mammography screening in the last two years. The five years risk for breast cancer was high in 15.8% of women according to the Gail model and ten years risk was high in 21.7% with the Cuzick-Tyrer model. In the present study, the breast cancer risk levels were assessed in a population setting for the first time in Turkey using breast cancer risk level assessment models. Being in 60-69 age group, having low education and not being in menopause were significant risk factors for not having mammography according to logistic regression analysis. Mammography utilization rate was low. Women must be educated about breast cancer screening methods and early diagnosis. The women in the high risk group should be informed on their risk status which may increase their attendance at breast cancer screening.

• Korean Medical Education Review
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• v.15 no.2
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• pp.87-92
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• 2013

The purpose of this study was to assess third-year medical students' competency for development or revision of the undergraduate curriculum and assessments. One hundred and twenty-seven third-year medical students at the Pusan National University were included in the study. After third- and fourth-year students took a common written examination, clinical performance examination (CPX), and objective structured clinical examination (OSCE) with common items as a summative assessment, the third-year students' competency was compared with 132 forth-year students' results. The correlation of the written examination and CPX/OSCE was analysed, and the summative results were compared with the grade point average (GPA) through the second year, CPX/ OSCE in the second year, and GPA in the clerkship. On the written examination, the third-year students' mean score was lower than the fourth-year students' by over 11 points, whereas the gap in the CPX/OSCE was 4 points and there was no difference in the OSCE. There was a moderate correlation between the written examination and the CPX/OSCE scores (R=0.371, p<0.01). The written examination was highly correlated with GPA through the second year, which mainly evaluated medical knowledge (R=0.771, p<0.01). A relatively high correlation was observed between CPX/OSCE scores and GPA in the clerkship (R=0.641, p<0.01). The summative CPX/ OSCE scores showed a moderate correlation with formative CPX/OSCE scores in the second year (R=0.464, p< 0.01). The third-year students' score was quite low on the written examination and slightly low on the CPX/OSCE compared to that of the fourth-year students. The written examination and CPX/OSCE cannot replace each other and should be combined with other methods of evaluation to measure competency. Early OSCE and workplacebased assessment should be useful in the early assessment of clinical skills competency.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.43 no.3
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• pp.247-254
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• 2017

Optical Coherence Tomography (OCT) is a non-invasive imaging method that utilizes the optical scattering and interference for visualizing the surface as well as cross-sectional structures of tissue. OCT has been used for diagnosing diseases in early stage in various medical fields, but an application in cosmetics is still at early stage. In this study, OCT was adopted to evaluate skin texture and wrinkle. Results showed similar patterns of evaluation with PRIMOS in the assessment using replica. In addition, OCT produced smaller errors at different angles compared to the PRIMOS in the assessment using 3-dimensional models of wrinkles. The resolution of the image was also high enough to differentiate the images of before and after the application of makeup products. Possible use of OCT in the evaluation of fine wrinkle assessment was studied in this research. Further development of methods is necessary to provide more evidences of the effectiveness.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.6
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• pp.2781-2785
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• 2016

Background: Matric metalloproteinase (MMP) 13 gene expression is increased in esophageal squamous cell carcinomas (ESCCs) and associated with increasing tumor invasion, lymph node involvement and decreased survival rates. Levels of the circulating enzyme may be elevated and used as a marker of tumor progression. In this study, clinical application of MMP-13 serum levels was evaluated for early detection, prediction of prognosis and survival time of ESCC patients. Materials and Methods: Serum levels of MMP13 were determined by ELISA in 66 ESCC patients prior of any treatment and 54 healthy controls for comparison with clinicopathological data through statistical analysis with Man Whitney U and Log-Rank tests. In addition, clinical value of MMP13 levels for diagnosis was evaluated by receiver operating characteristic (ROC) test. Results: The serum level of MMP-13 in patients (>250 pg/ml) was significantly higher than in the control group (<100 pg/ml) (p value=0.004). Also the results showed a significant correlation between MMP-13 serum levels with tumor stage (p value = 0.003), depth of tumor invasion (p value=0.008), involvement of lymph nodes (p value = 0.011), tumor size (p value = 0.018) and survival time. While there were no significant correlation with grade and location of tumors. ROC analysis showed that MMP-13 level is an accurate diagnostic marker especially to differentiate pre-invasive/ invasive lesions from normal controls (sensitivity and specificity: 100%). Conclusions: These findings indicate a potential clinical significance of serum MMP13 measurement for early detection and prognostic assessment in ESCC patients.