• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.715-731
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• 2021

Uncertainties are calculated for pressurized water reactor (PWR) spent nuclear fuel (SNF) characteristics. The deterministic code STREAM is currently being used as an SNF analysis tool to obtain isotopic inventory, radioactivity, decay heat, neutron and gamma source strengths. The SNF analysis capability of STREAM was recently validated. However, the uncertainty analysis is yet to be conducted. To estimate the uncertainty due to nuclear data, STREAM is used to perturb nuclear cross section (XS) and resonance integral (RI) libraries produced by NJOY99. The perturbation of XS and RI involves the stochastic sampling of ENDF/B-VII.1 covariance data. To estimate the uncertainty due to modeling parameters (fuel design and irradiation history), surrogate models are built based on polynomial chaos expansion (PCE) and variance-based sensitivity indices (i.e., Sobol' indices) are employed to perform global sensitivity analysis (GSA). The calculation results indicate that uncertainty of SNF due to modeling parameters are also very important and as a result can contribute significantly to the difference of uncertainties due to nuclear data and modeling parameters. In addition, the surrogate model offers a computationally efficient approach with significantly reduced computation time, to accurately evaluate uncertainties of SNF integral characteristics.

• Journal of Korea Entertainment Industry Association
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• v.13 no.1
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• pp.185-197
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• 2019

This study intended to analyze the early childhood education freshmen's academic interest. For this study relationship among academic self-efficacy, character strength and learning motivation. The study subjects were 144 early childhood education freshmen at K-college in Deagu. They answered the survey regarding academic self-efficacy scale, VIA-IS(Values in action inventory of strength) short form scale, school learning motivation scale. The collected data were analyzed by frequency analysis, descriptive statistics, pearson correlation and multiple regression analysis using SPSS 18.0 program. The study finding are as follows. First, the average of academic self-efficacy, character strength and learning motivation of students were near at the intermediate-level. Second, academic self-efficacy, character strength and learning motivation were significantly positive correlated. Third, when examining the relative effect of early childhood education freshmen's academic self-efficacy and character strength on learning motivation, self regulatory efficacy among the sub-factors for academic self-efficacy and courage among the sub-factors for character strengths.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.33 no.1
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• pp.16-23
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• 2022

Objectives: Early detection of developmental issues in infants and necessary intervention are important. To identify the comorbid conditions, a comprehensive evaluation is required. The study's objectives were to 1) generate scale items by identifying and eliciting concepts relevant to young children (12-71 months) with developmental delays, 2) develop a comprehensive screening tool for developmental delay and comorbid conditions, and 3) assess the tool's validity and cut-off. Methods: Multidisciplinary experts devised the "Infant Comprehensive Evaluation for Neurodevelopmental Delay (ICEND)," an assessment method that comes in two versions depending on the age of the child: 12-36 months and 37-71 months, through monthly seminars and focused group interviews. The ICEND is composed of three parts: risk factors, resilience factors, and clinical scales. In parts 1 and 2, there were 41 caretakers responded to the questionnaires. Part 3 involved clinicians evaluating ten subscales using 98 and 114 questionnaires for younger and older versions, respectively. The Child Behavior Checklist, Strengths and Difficulties Questionnaire, Infant-Toddler Social Emotional Assessment, and Korean Developmental Screening Test for Infants and Children were employed to analyze concurrent validity with the ICEND. The analyses were performed on both typical and high-risk infants to identify concurrent validity, reliability, and cut-off scores. Results: A total of 296 people participated in the study, with 57 of them being high-risk (19.2%). The Cronbach's alpha was positive (0.533-0.928). In the majority of domains, the ICEND demonstrated a fair discriminatory ability, with a sensitivity of 0.5-0.7 and specificity 0.7-0.9. Conclusion: The ICEND is reliable and valid, indicating its potential as an auxiliary tool for assessing neurodevelopmental delay and comorbid conditions in children aged 12-36 months and 37-71 months.

• The Journal of Korean Academic Society of Nursing Education
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• v.28 no.2
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• pp.193-203
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• 2022

Purpose: This study explored the mediating role of resilience between post-traumatic stress and emotional exhaustion in nurses during the COVID-19 pandemic. Methods: The data were collected from 193 nurses working at a hospital in Daegu from October 16 to 30, 2020, in the middle of the COVID-19 pandemic. Participants conducted self-reported surveys of post-traumatic stress (Impact of Event Scale-Revised Korean version), emotional exhaustion (Maslach Burnout Inventory), and resilience (Korean Resilience Quotient Test). The data were analyzed using descriptive statistics, frequency, t-tests, Mann-Whitney U tests, Kruskal-Wallis tests, Pearson correlation coefficients, and multiple regression. Mediation analysis was performed using the Baron and Kenny method and Sobel test. Results: The mean scores for post-traumatic stress, resilience, and emotional exhaustion were 16.18±16.18, 183.41±18.29, and 32.64±9.66, respectively. A higher level of post-traumatic stress was associated with lower resilience (r=-.20, p=.004) and with higher emotional exhaustion (r=.33, p<.001). A higher level of resilience was associated with lower emotional exhaustion (r=-.35, p<.001). The resilience was confirmed to have a partial mediating effect in the relationship between post-traumatic stress and emotional exhaustion, verified by the Sobel test (Z=2.31, p=.02). Conclusion: Resilience had a partial mediating effect in the relationship between post-traumatic stress and emotional exhaustion. Thus, nurses should develop individual strengths to reduce emotional exhaustion, and managers should also make efforts to increase the nurses' resilience. It is also necessary to develop and apply a program to strengthen nurses' resilience.

• Journal of the Korea Concrete Institute
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• v.29 no.4
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• pp.379-387
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• 2017

The objective of this study is to develop sustainable PVA fiber-reinforced cementitious composites (FRCCs) that could exhibit comparable strength level to normal PVA FRCCs with no recycled materials. To evaluate mechanical properties of the FRCCs, compressive, flexural and direct tensile tests were conducted. In addition to the test, to calculate amount of carbon dioxide ($CO_2$) emission at the stage of manufacturing the FRCCs, life cycle inventory data base (LCI DB) were referenced from domestic and Japan. From the test results, the mechanical properties such as compressive, flexural and direct tensile strengths were decreased as the replacement ratio of recycled materials increased. And it was determined that the amount of $CO_2$ emission was reduced for the specimens with higher water-binder ratio (W/B) and replacement ratios. It was also found that binder intensity ($B_i$) value was higher as replacement ratio of fly ash (FA) increased. This result means that larger amount of FA is need to deliver one unit of a given performance indicator (1 MPa of strength) of FRCCs compared to that of ordinary portland cement (OPC). As a result, it could be concluded that FRCCs with W/B 45% replaced by FA 25% and recycled sand (RS) 25% is desirable for both target performance and $CO_2$ emission.

• Korean Journal of Psychosomatic Medicine
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• v.26 no.1
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• pp.9-18
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• 2018

Objectives : The aims of this study were to investigate the psychopathology in adolescents with internalizing disorder using the self-report version of Strengths and Difficulties Questionnaire (SDQ-SR) and the Minnesota Multiphasic Personality Inventory for adolescents (MMPI-A), and to explore the complementarity between these two inventories for diagnostic assessment. Methods : Ninety-one patients aged 13-17 were divided into two groups by clinical diagnosis, 44 with internalizing disorder and 47 comparison group with other disorders. The data of SDQ-SR and MMPI-A completed by them were analyzed for the ability to predict internalizing disorder. Results : The logistic regression analysis revealed that diagnostic predictability increased by 2.27 times with every 1 point of SDQ-SR emotional symptom score increment. Comparison of ROC curves for internalizing disorders showed that the SE and SP of SDQ-SR emotional symptom with score over 4 was 88.94 and 78.72, respectively. For A-anx of MMPI-A with score over 56, SE and SP was 77.27 and 74.47, respectively. However, combination of these scales could not enhance the predictability of diagnostic classification more than that of SDQ-SR emotional symptom alone. Conclusions : Emotional symptom scale of SDQ-SR and A-anx, A-aln, A and INTR of MMPI-A should be important subscales for diagnosing the internalizing disorder of adolescents, however, which needs to be examined further with a larger sample size including normal control group.

• Korean Journal of Remote Sensing
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• v.30 no.5
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• pp.651-664
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• 2014

Recently, the demands of accurate forest carbon stock estimation and mapping are increasing in Korea. This study investigates the feasibility of two methods, k-Nearest Neighbor (kNN) and Regression Tree Analysis (RTA), for carbon stock estimation of pilot areas, Gongju and Sejong cities. The 3rd and 5th ~ 6th NFI data were collected together with Landsat TM acquired in 1992, 2010 and Aster in 2009. Additionally, various vegetation indices and tasseled cap transformation were created for better estimation. Comparison between two methods was conducted by evaluating carbon statistics and visualizing carbon distributions on the map. The comparisons indicated clear strengths and weaknesses of two methods: kNN method has produced more consistent estimates regardless of types of satellite images, but its carbon maps were somewhat smooth to represent the dense carbon areas, particularly for Aster 2009 case. Meanwhile, RTA method has produced better performance on mean bias results and representation of dense carbon areas, but they were more subject to types of satellite images, representing high variability in spatial patterns of carbon maps. Finally, in order to identify the increases in carbon stock of study area, we created the difference maps by subtracting the 1992 carbon map from the 2009 and 2010 carbon maps. Consequently, it was found that the total carbon stock in Gongju and Sejong cities was drastically increased during that period.

• Clinical and Experimental Pediatrics
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• v.49 no.5
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• pp.523-528
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• 2006

Purpose : The purpose of this study was to investigate the relationship between depression and resilience in adolescents with congenital heart disease(CHD) and to identify the variables associated with depression. Methods : The Resilience Scale(cronbach's ${\alpha}=0.92$), Children's Depression Inventory(cronbach's ${\alpha}=0.72$) and Maternal Behavior Research Instrument(cronbach's ${\alpha}=0.88$) were applied and analyzed to assess depression and resilience among 231 adolescents after surgery for CHD from three major cardiac centers in Korea. This group consist of 114 males and 117 females. The mean age was 15.8 years(range : 13-18 years). The clinical severity of illness was rated by CHD functional index and NYHA functional class. Results : The mean score for depression and resilience was 16.74(range : 0-49) and 115.84(range : 70-132) respectively. Depression was significantly related to age(r=0.25, P<0.001) and NYHA functional class(r=0.35, P<0.001), as well as being negatively correlated with oxygen saturation(r=-0.39, P<0.001), academic achievement(r=-0.41, P<0.001), parental attitude(r=-0.49, P<0.001) and resilience (r=-0.59, P<0.001). The results of multiple regression analysis showed that parental attitude(${\beta}=-0.48$, P<0.01) and resilience(${\beta}=-0.62$, P<0.01) were related to depression. Conclusion : This study demonstrated that adolescents with CHD had a higher resilience and were less depressed with an affectionate parent. With respect to medical and nursing intervention programs, it is essential to identify strengths of adolescents with CHD in order to increase their resilience. Additionally, it is also important that parenting and counseling programs be implemented for the parents of adolescents with CHD.