• Journal of The Geomorphological Association of Korea
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• v.27 no.3
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• pp.87-103
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• 2020

The purpose of this study is to evaluate the risk of cropland and man-made infrastructures in a landslide-prone area using a GIS-based method. To achieve this goal, a landslide inventory map was prepared based on aerial photograph analysis as well as field observations. A total of 550 landslides have been counted in the entire study area. For model analysis and validation, extracted landslides were randomly selected and divided into two groups. The landslide causative factors such as slope, aspect, curvature, topographic wetness index, elevation, forest type, forest crown density, geology, land-use, soil drainage, and soil texture were used in the analysis. Moreover, to identify the correlation between landslides and causative factors, pixels were divided into several classes and frequency ratio was also extracted. A landslide susceptibility map was constructed using a bayesian predictive model (BPM) based on the entire events. In the cross validation process, the landslide susceptibility map as well as observation data were plotted with a receiver operating characteristic (ROC) curve then the area under the curve (AUC) was calculated and tried to extract a success rate curve. The results showed that, the BPM produced 85.8% accuracy. We believed that the model was acceptable for the landslide susceptibility analysis of the study area. In addition, for risk assessment, monetary value (local) and vulnerability scale were added for each social thematic data layers, which were then converted into US dollar considering landslide occurrence time. Moreover, the total number of the study area pixels and predictive landslide affected pixels were considered for making a probability table. Matching with the affected number, 5,000 landslide pixels were assumed to run for final calculation. Based on the result, cropland showed the estimated total risk as US $ 35.4 million and man-made infrastructure risk amounted to US $ 39.3 million.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.344-352
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• 2019

Marine production strings are continuously affected by unstable internal fluid during operation. In this paper, the structural governing equation for marine production string self-induced vibration is constructed. A finite element analysis model is established based on Euler-Bernoulli theory and solved by the Newmark method. Furthermore, based on reliability theory, a self-design procedure is developed to determine the operability envelope for marine production string self-induced vibration. Case studies show: the response frequency of the production strings is consistent with the excitation frequency under harmonic fluctuation and mainly determined by the first-order natural frequency under stochastic fluctuation. The operability envelope for marine production string self-induced vibration is a near symmetrical trapezium. With the increasing of natural gas output, the permissible fluctuation coefficient dramatically decreases. A reasonable centralizer spacing, increasing top tension, and controlling natural gas output are of great significance to the risk control in marine production string operation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2244-2250
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• 2013

The purpose of this study was to examine the frequency of daily toothbrushing among Korean adolescents. The Korea Youth Risk Behavior Web-based Survey data were analysed. subject included 75,238 in 2008, 75,066 in 2009 and 73,238 in 2010, which included a nationally representative sample of middle and high school students. The frequency of daily toothbrushing was analysed according to socioeconomic status (gender, age, residential areas, type of school, parents' education and occupation). All survey data collected was processed using SPSS ver 19.0 for data analyses such as frequency analysis, t-test and Chi-square. The mean frequency of daily toothbrushing for 2008 was 3.92, 2009 was 3.96 and 2010 was 3.99. The appearance of toothbrushing after having lunch at school was indicated to be 34.5% in 2008, 38.0% in 2009 and 40.8% in 2010. This study has shown that need to systematic oral health promotion programmes for adolescent in Korea.

• Korea Journal of Hospital Management
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• v.25 no.4
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• pp.103-111
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• 2020

Objectives: The study recognizes the seriousness of depression in youth with atopic dermatitis, and tries to identify factors that affect depression. Methods: Data were obtained from the 2014 Korean Youth Health Behavior Risk Behavior On-line Survey. In this study, 17,232 people who were Atopic dermatitis without missing variables were included in the final analysis. It conducted frequency, chi-square and logistic regression analysis by SPSS 20.0. Results: An analysis of factors affecting depression showed that subjective health level, subjective happiness satisfaction, subjective sleep satisfaction, subjective stress level, smoking, and drinking had an effect. Conclusions: The factors affecting youth depression with atopic dermatitis revealed health status, life behavior. These results are thought to require attention and research on youth with atopic dermatitis, along with the development of practical treatment programs and systematic management by applying them to teenagers in an appropriate time and method.

• Journal of the Society of Disaster Information
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• v.17 no.1
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• pp.81-96
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• 2021

Purpose: Based on the preceding studies in supply chain management, factors were analyzed to verify the effect of risk assessment and risk management factors of the business continuity management system (BCMS) on management performance. The purpose of this study is to establish a systematic risk management plan by deriving the risk factors of BCMS and evaluating unpredictable risks, and at the same time, contributing to a company's competitive advantage without interruption of work. Method: The structural relationship between risk assessment, risk management and management performance of BCMS was derived. To this end, a questionnaire survey was conducted of 124 managers and managers in Korean companies. Frequency analysis, validity analysis, reliability analysis, correlation analysis, and simple regression analysis were performed. Result: First, risk assessment had a positive (+) effect on risk management. Second, risk management had a positive (+) effect on management performance. Finally, risk assessment had a positive (+) effect on management performance. Conclusion: BCMS's risk assessment and risk management capabilities should be managed through financial performance, and risk management activities should be managed through non-financial performance.

• Journal of the Korean Dietetic Association
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• v.23 no.4
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• pp.397-407
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• 2017

This study was conducted to explore socio-demographic influences on eating behaviors among adolescents in Korea. Data were obtained from the Eleventh Korea Youth Risk Behavior Web-based Survey (2015 KYRBS), a nationwide representative sample of 3,532,149 middle and high school students. The data were analyzed by descriptive analysis, t-test, and logistic regression based on complex sample design using SPSS 20.0 statistics. The results showed that intake frequency of soda, fast food, and instant noodles was higher in male than female students (P<0.001). Additionally, the frequency of eating breakfast, fruits, vegetables, and milk was higher among high school students than middle school students (P<0.001). Higher levels of economic status were associated with less skipping breakfast. Adolescents with mothers that had higher levels of education were more likely to be frequent consumers of fruits, vegetables, and milk, and to eat breakfast.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.3
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• pp.57-69
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• 2016

In this study, we analyzed the extreme rainfall distribution scenarios based on probable rainfall calculation and applying various time distribution models over the landslide high risk zones in urban areas. We used observed rainfall data form total 71 ASOS (Automated Synoptic Observing System) station and AWS (Automatic Weather Station) in KMA (Korea Meteorological Administration), and we analyzed the linear trends for 1-hr and 24-hr annual maximum rainfall series using simple linear regression method, which are identified their increasing trends with slopes of 0.035 and 0.660 during 1961-2014, respectively. The Gumbel distribution was applied to obtain the return period and probability precipitation for each duration. The IDF (Intensity-Duration-Frequency) curves for landslide high risk zones were derived by applying integrated probability precipitation intensity equation. Results from IDF analysis indicate that the probability precipitation varies from 31.4~38.3 % for 1 hr duration, and 33.0~47.9 % for 24 hr duration. It also showed different results for each area. The $Huff-4^{th}$ Quartile method as well as Mononobe distribution were selected as the rainfall distribution scenarios of landslide high risk zones. The results of this study can be used to provide boundary conditions for slope collapse analysis, to analyze sediment disaster risk, and to use as input data for risk prediction of debris flow.

• Magazine of the Korean Society of Agricultural Engineers
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• v.27 no.2
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• pp.23-37
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• 1985

This studies were carried out to get characteristics of frequency distribution, probable flood flows according to the return periods, and the correlation between return periods and those length of records affect the Risk of failure in the annual maximum series of the main river systems in Korea. Especially, Risk analysis according to the levels were emphasized in relation to the design frequency factors for the different watersheds. Twelve watersheds along Han, Geum, Nak Dong, Yeong San and Seom Jin river basin were selected as studying basins. The results were analyzed and summarized as follows. 1. Type 1 extremal distribution was newly confirmed as a good fitted distribution at selected watersheds along Geum and Yeong San river basin. Three parameter lognormal Seom Jin river basin. Consequently, characteristics of frequency distribution for the extreme value series could be changed in connection with the watershed location even the same river system judging from the results so far obtained by author. 2. Evaluation of parameters for Type 1 extremal and three parameter lognormal distribution based on the method of moment by using an electronic computer. 3. Formulas for the probable flood flows were derived for the three parameter lognormal and Type 1 extremal distribution. 4. Equations for the risk to failure could be simplified as $\frac{n}{N+n}$ and $\frac{n}{T}$ under the condition of non-parametric method and the longer return period than the life of project, respectively. 5. Formulas for the return periods in relation to frequency factors were derived by the least square method for the three parameter lognormal and Type 1 extremal distribution. 6. The more the length of records, the lesser the risk of failure, and it was appeared that the risk of failure was increasing in propotion to the length of return periods even same length of records. 7. Empirical formulas for design frequency factors were derived from under the condition of the return periods identify with the life of Hydraulic structure in relation to the risk level. 8. Design frequency factor was appeared to be increased in propotion to the return periods while it is in inverse proportion to the levels of the risk of failure. 9. Derivation of design flood including the risk of failure could be accomplished by using of emprical formulas for the design frequency factor for each watershed.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.32 no.4
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• pp.161-169
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• 2021

Objectives: Adolescent suicide is a serious social problem. Adolescent alcohol use is one of the most important risk factors for adolescent suicide. This study aimed to identify the relationship between drinking habits and suicide among Korean adolescents. Methods: Data from the 14th and 15th Korean Youth Risk Behavior Web-based Survey, conducted in 2018 and 2019, were used for analysis. Multiple logistic regression analysis was used to identify the relationship between drinking habits-including the age of drinking initiation, frequency of drinking, average drinking amount, frequency of drunkenness-and suicidal ideation, plans, and attempts. Results: Even after adjusting for age, sex, school grade, academic achievement, socioeconomic status, depression, stress, and drinking habits, the frequencies of drinking and drunkenness increased the risk of suicide attempts. Suicide attempts were associated with the frequency of drinking in girls and middle school students, and with the frequency of drunkenness in boys and high school students. Conclusion: This study identified associations between drinking habits (the age of drinking initiation, frequency of drinking, average amount of drinking, frequency of drunkenness) and suicidal behavior in adolescents. Our findings suggest that to prevent adolescent suicide, it might be necessary to investigate drinking habits, including the frequencies of drinking and drunkenness. Moreover, considering the differences in sex and school grade, it is important to include the individual group characteristics when evaluating drinking habits.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.7
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• pp.1247-1257
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• 2001

The objectives of the study were to examine apparel purchasing behavior in internet shopping malls and the level of perceived risk when internet users purchase online. For this research, 15,000 internet users were given questionaries via E-mail, or special website online. The sum of 1958 questionaries were used for statistical analyses. Using, SAS package, factor analysis, Crobach's ${\alpha}$, t-test, $\chi$$^2$-test, frequency and multi-response analysis were performed. As the results, 19% out of internet users had bought apparel products through internet shopping malls. Men had more purchasing experiences in apparels as well as general products than women. Among apparel products, T-shirts/shirts were purchased the most by internet shoppers. For perceived risks, 6 factors(quality risk, time/convenience risk, size and appearance risk, privacy risk and social/psychological risk) were investigated for this study. The level of perceived risk was lower when people had a purchasing experience in internet shopping mall than when they didn't. The level of perceived risk was lower when people had purchasing intend about apparels than when they didn't. Based on these results, marketing strategies will be suggested.