• Korean Journal of Radiology
• /
• v.21 no.1
• /
• pp.88-100
• /
• 2020

Objective: We aimed to develop and validate a deep learning system for fully automated segmentation of abdominal muscle and fat areas on computed tomography (CT) images. Materials and Methods: A fully convolutional network-based segmentation system was developed using a training dataset of 883 CT scans from 467 subjects. Axial CT images obtained at the inferior endplate level of the 3rd lumbar vertebra were used for the analysis. Manually drawn segmentation maps of the skeletal muscle, visceral fat, and subcutaneous fat were created to serve as ground truth data. The performance of the fully convolutional network-based segmentation system was evaluated using the Dice similarity coefficient and cross-sectional area error, for both a separate internal validation dataset (426 CT scans from 308 subjects) and an external validation dataset (171 CT scans from 171 subjects from two outside hospitals). Results: The mean Dice similarity coefficients for muscle, subcutaneous fat, and visceral fat were high for both the internal (0.96, 0.97, and 0.97, respectively) and external (0.97, 0.97, and 0.97, respectively) validation datasets, while the mean cross-sectional area errors for muscle, subcutaneous fat, and visceral fat were low for both internal (2.1%, 3.8%, and 1.8%, respectively) and external (2.7%, 4.6%, and 2.3%, respectively) validation datasets. Conclusion: The fully convolutional network-based segmentation system exhibited high performance and accuracy in the automatic segmentation of abdominal muscle and fat on CT images.

• Journal of Korean Society of Forest Science
• /
• v.113 no.3
• /
• pp.339-348
• /
• 2024

Debris flow is a typical type of mountainous sediment disaster that can cause widespread damage to both lives and property, making it essential to understand its behavioral characteristics for effective prevention. In this study, pre- and post-event Light Detection And Ranging(LiDAR) data from the Dosan-ri area in Bonghyeon-myeon, Yeongju-si, Gyeongsangbuk-do, Republic of Korea where debris flows occurred in 2023, were used to calculate the actual affected area and terrain change volume caused by the debris flow. These calculated values were then compared with those derived from the numeric simulation model, Morpho2DH, based on field surveys and laboratory investigation data. Additionally, the model's applicability was assessed by conducting cross-sectional elevation analyses based on the extent of the affected area and comparisons of the results. The findings indicate that the debris flow affected area and terrain change volume estimated by the Morpho2DH model were approximately 152% and 178% higher, respectively, compared to the LiDAR-based results. Pearson correlation analysis of the cross-sectional elevation changes showed a positive correlation, with Pearson Correlation Coefficients(PCC) of at least 0.65

• Journal of Korea Water Resources Association
• /
• v.53 no.7
• /
• pp.533-543
• /
• 2020

In order to provide information for proper management of groundwater resources, it is necessary to estimate the rise time of groundwater level by calculating the delay time between the time series of precipitation and groundwater level and to understand the characteristics of groundwater level variation. In this study, total delay time (TDT) and cross correlation coefficient between the moving averaged precipitation generated by using the moving average method to take into account the preceding precipitation and the groundwater level were calculated and analyzed for the nine groundwater level monitoring wells in the Pyoseon watershed in the southeast of Jeju Island. As a result, when the moving averaged precipitation was used, the correlation with the groundwater level was higher in all monitoring wells than in the case of using the raw precipitation, so that it was possible to more clearly estimate the delay time between precipitation and groundwater level. When using the moving averaged precipitation, it had cross correlation coefficients of up to 0.57 ~ 0.58 with the time series data of the groundwater level, and had a relatively high correlation when considering the preceding precipitation of about 24 days on average. The TDT was about 32 days on average, and it was confirmed that the consideration of preceding precipitation plays an important role in estimating the TDT because the days of moving averaged precipitation greatly influences the calculation of the TDT. In addition, through the use of moving averaged precipitation, we found an error in estimating the TDT due to the use of raw precipitation. Through the method of estimating the TDT used in this study and the use of the R code for estimating the TDT presented in the appendix of this paper, it will be possible to estimate the TDT for other regions in the future relatively easily.

• (The) Korean Journal of Educational Psychology
• /
• v.32 no.1
• /
• pp.99-130
• /
• 2018

The purpose of this study was to examine the longitudinal relationship between resilience and social support of school violence exposure types including school bullying, victimization, and dual experience. The study used data obtained from the third year (2012) of the Seoul Education Longitudinal Study of 1,137 elementary school students in grade 6 who reported experiencing school violence. The results of the autoregressive cross-lagged model are as follows. First, as a result of measuring the self-regression coefficients of resilience and social support of the youth exposed to school violence at 3 time points (2012, 2014, and 2016), it was found for all types of violence that resilience and social support at the previous time point showed a signigicant positive effect on the same variable at the next time point. Second, in the case of the cross-lagged effects of resilience and social support, the effect of previous social support on resilience at the next time point was statistically significant for the victimization group, but not for the bullying or dual experience groups. Third, considering the opposite path from resilience to social support, resilience at the previous time point had a significant influence on the social support at the next time point for both the bullying and victimization groups. This result is new and can be complementary to the cross-sectional studies so far using a longitudinal view. The results of this study suggest that the bullying and victimized students who are relatively more resilient are less likely to perceive social support than those who are not resilient. Finally, we discuss the longitudinal relationship between resilience and social support, the limitations of this study, and implications for future research.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.2
• /
• pp.160-165
• /
• 2007

Dispersion parameters for the number of piglets born alive were estimated using a repeatability and random regression model. Six sow breeds/lines were included in the analysis: Swedish Landrace, Large White and both crossbred lines between them, German Landrace and their cross with Large White. Fixed part of the model included sow genotype, mating season as month-year interaction, parity and weaning to conception interval as class effects. The age at farrowing was modelled as a quadratic regression nested within parity. The previous lactation length was fitted as a linear regression. Random regressions for parity on Legendre polynomials were included for direct additive genetic, permanent environmental, and common litter environmental effects. Orthogonal Legendre polynomials from the linear to the cubic power were fitted. In the repeatability model estimate of heritability was 0.07, permanent environmental effect as ratio was 0.04, and common litter environmental effect as ratio was 0.01. Estimates of genetic parameters with the random regression model were generally higher than in the repeatability model, except for the common litter environmental effect. Estimates of heritability ranged from 0.06 to 0.10. Permanent environmental effect as a ratio increased along a trajectory from 0.03 to 0.11. Magnitudes of common litter effect were small (around 0.01). The eigenvalues of covariance functions showed that between 7 and 8 % of genetic variability was explained by individual genetic curves of sows. This proportion was mainly covered by linear and quadratic coefficients. Results suggest that the random regression model could be used for genetic analysis of litter size.

• Journal of Digital Convergence
• /
• v.11 no.12
• /
• pp.657-663
• /
• 2013

This study aimed to identify factors that influence depression in juvenile offenders. A cross-sectional study design was used. The participants were 275 juvenile offenders from D city. The collected data were analyzed using t-test, ANOVA, Pearson's correlation coefficients, and multiple regression with the SPSS/WIN 20.0 program. Of the participants, 32.4% and 52.0% were in the clinical group for ADHD and depression, respectively. ADHD symptoms and self-esteem were significantly correlated with depression. The final model showed that depression among juvenile offenders was significantly influenced by perceived health status, ADHD symptoms, and self-esteem. These variables accounted for 37% of the variance of depression.

• Journal of the Korean Home Economics Association
• /
• v.24 no.2
• /
• pp.37-50
• /
• 1986

A nutrition survey of 128 perschool children, 4 to 6 years old, in the Saemaul Youlgok day care center, located in one uplane, overpolulated, poor area of the city of Seoul, sponsered by the Korean Red Cross Society, was undertaken between August 21 and 31, 1984, to investigate dietary and nutritional status. RESULTS: Mean values of height, weight, arm circumference, girth of chest, and head circumference ranged from 95 to 100% of KIST mean. However, 4.8~14.2% of the subjects were assessed as undernourished in terms of 'weight for height'. Mean hemoglobin vcalue was 12.1±0.7gm%, and mean hematocrit value was 38.5±2.2%; 4.1% of the subjects were proven to be anemic according to the criterion of hemoglobin established by the ICNND. Mean urinary urea nitrogen/creatinine ratio was 11.4±3.8. Regarding mean energy and nutrient intake, the following percentages had intakes below two-thirds of the 1985 RDAs: 28.8% of children, for protein; 48.8% of children, for iron; and 28.8% of children, for calcium. About 25% of children had vitamin A intake below one-third of the recommended allowance. Carbohydrate provided 71% of total energy intake; protein accounted for 13%; fat provided 16%. Energy intake was divided among breakfast, lunch, dinner and snacks in a percentage ration of 19:26:21:34. The lunch, and snacks which were served at the day care center provided 36.5~79.1% of daily energy and nutrient intake. The survey clarified that the day care feding largely supplemented the inadequate dietary intakes of these young children at home. According to factor analysis of energy and nutrient intake, there were two factor groups : the first factor group, for energy, protein, carbohydrate, iron and niacin, mainly provided by grains; and the second factor group, for calcium, vitamin A, thamin, riboflavin and ascorbic acid, provided by vegetables, fruits, milk and milk products. The survey also revealed significant correlation coefficients between family factors such as family income, educational level of parents, and number of children; and dietary or nutritional status of the subjects.

• Women's Health Nursing
• /
• v.26 no.1
• /
• pp.49-60
• /
• 2020

Purpose: Infertile women experience various physical, psychological, and relational problems that affect their infertility-related quality of life (QoL). This study investigated infertile women's infertility-related QoL with the goal of identifying how it is influenced by fatigue, depression, and marital intimacy. Methods: A sample of 140 infertile women was surveyed in a cross-sectional study. Data were collected from February to April 2018 using self-report structured questionnaires at three infertility clinics located in Jeonju, Korea. Data were analyzed using the independent t-test, analysis of variance, Pearson correlation coefficients, and stepwise multiple regression analysis in SPSS for Windows version 25.0. The subjects agreed to complete a face-to-face interview, including administration of the Fatigue Severity Scale, Depression Anxiety Stress Scale-21, Marital Intimacy Scale, and the Fertility Quality of Life tool. Results: The mean age of the participants was 35.6±4.3 years. Infertility-related QoL was negatively correlated with fatigue (r=-.42, p<.001) and depression (r=-.56, p<.001), and positively correlated with marital intimacy (r=.30, p<.001). Multiple regression analysis showed that depression (β=-0.44, p<.001), fatigue (β=-0.27, p<.001), and husband's attitude (β=-0.19, p=.007) had significant effects on the QoL of infertile women, accounting for 40.5% of the variance in infertility-related QoL. Conclusion: The study provides insights into how infertile women's infertility-related QoL was influenced by depression, fatigue, and their husbands' attitudes regarding infertility treatment. To improve infertile women's infertility-related QoL, healthcare providers should consider developing strategies to decrease depression and fatigue in infertile women and to address their husbands' attitudes.

• Women's Health Nursing
• /
• v.26 no.1
• /
• pp.84-92
• /
• 2020

Purpose: The objective of this study was to identify the factors influencing maternal identity in pregnant women. Methods: Using a descriptive research design, a cross-sectional survey was conducted. In total, 127 pregnant women were recruited from a tertiary hospital in Korea from January to April 2019. Measurements included maternal identity, stress, depression, spousal and familial support, and demographic and obstetric characteristics. Data were analyzed by descriptive statistics, the independent t-test, one-way ANOVA, Pearson correlation coefficients, and stepwise multiple regression using SPSS version 25.0. Results: The mean score for maternal identity was 131.15 out of 160, and the mean scores for stress, depression, and spousal and familial support were 14.59 (out of 40), 6.82 (out of 30), and 109.04 (out of 132), respectively. Stress (r=-.38, p<.001), depression (r=-.37, p<.001), and spousal and familial support (r=.37, p<.001) were significantly correlated with maternal identity. In multiple regression analysis, stress (β=-0.27, p=.005) and spousal and familial support (β=0.23, p=.014) were found to be significant factors influencing maternal identity in pregnant women (F=14.19, p<.001). Conclusion: It is necessary to develop effective strategies to mitigate stress and to encourage spousal and familial support in pregnant women. Such strategies could further enable pregnant women to enhance their maternal identity.

• Women's Health Nursing
• /
• v.26 no.1
• /
• pp.28-36
• /
• 2020

Purpose: This study investigated lifestyle, depression, marital intimacy, and quality of life (QoL) in breast cancer survivors, with the goal of identifying the impacts of these factors on QoL. Methods: A sample of 146 breast cancer survivors was surveyed in this cross-sectional study. Data were collected from March 20 to May 30, 2019, using self-report structured questionnaires at a hospital located in Jeonju, Korea. Data were analyzed using the independent t-test, analysis of variance, Pearson correlation coefficients, and hierarchical regression analysis. Participants agreed to complete a face-to-face interview, including administration of the Health Promoting Lifestyle Profile II, Depression Anxiety Stress Scale 21-Depression Scale, Marital Intimacy Scale, and Functional Assessment Cancer Therapy-Breast Cancer tool. Results: QoL was positively correlated with lifestyle (r=.49, p<.001) and marital intimacy (r=.45, p<.001) and negatively correlated with depression (r=-.72, p<.001). Hierarchical multiple regression analysis showed that depression (β=-0.63, p<.001), marital intimacy (β=0.19, p=.001), and lifestyle (β=0.13, p=.031) had significant effects on the QoL of breast cancer survivors, accounting for 63.3% of variance in related QoL. Conclusion: This study provides insights into how breast cancer survivors' QoL was influenced by depression, marital intimacy, and lifestyle. To improve the QoL of breast cancer survivors, healthcare providers should consider developing strategies to decrease depression, to increase marital intimacy, and to improve lifestyle.