• Journal of the Korean Society of Safety
• /
• v.37 no.6
• /
• pp.148-157
• /
• 2022

Every year, particularly during the monsoon rainy season, landslides at the Chuncheon province of South Korea cause tremendous damage to lives, properties, and infrastructures. More so, the high rainfall intensity and long rainfall days that occurred in 2020 have increased the water content in the soil, thereby increasing the chances of landslide occurrences. Besides this, the rainfall thresholds and characteristics responsible for the initiation of landslides in this region have not been properly identified. Therefore, this paper addresses the rainfall thresholds responsible for the initiation of landslides at Chuncheon from a regional perspective. Using data obtained from rainfall measurements taken from 2002 to 2011, we identify a threshold relationship between rainfall intensity and rainfall duration for the initiation of landslides. In addition, we identify the relationship between the rainfall intensity using a 3-day, 7-day, and 10-day antecedent rainfall observation. Specifically, we estimate the rainfall data at 8 sites where debris flow occurred in 2011 by kriging. Following this, the estimated data are used to construct the relationship between the intensity (I), duration (D), and frequency (F) of rainfall. The results of the intensity-duration-frequency (IDF) analysis show that landslides will occur under a rainfall frequency below a 2-year return period at two areas in Chuncheon. These results will be effectively used to design structures that can prevent the occurrence of landslides in the future.

• Journal of Global Scholars of Marketing Science
• /
• v.15 no.2
• /
• pp.161-182
• /
• 2005

This paper reports on a study testing a model that articulates factors affecting duration of the relationship between exporters and importers. The model posits that affective commitment and calculative commitment influence duration of the relationship. Affective commitment of an importer toward an exporter is hypothesized to be predicted by social satisfaction, which in turn may be predicted by cultural familiarity, perceived similarity, and credibility. In contrast, calculative commitment is hypothesized to be predicted by economic satisfaction, which in turn may be predicted by opportunism and relationship performance. A survey of importers was conducted to test the model. The study results provided support for most of the hypotheses. Theoretical and managerial implications of the study results are discussed too.

• Journal of the East Asian Society of Dietary Life
• /
• v.20 no.3
• /
• pp.473-480
• /
• 2010

This study examined the different meal duration expectations and dining characteristics of customers each stage of service (order, cook, check), and investigated the impact of perceived meal duration on customers' satisfaction. The procedures consisted of four phases. During the first phase, the different meal duration expectations and dining characteristics of customers of an Italian restaurant in Seoul were examined by survey at each stage of service. The second phase investigated the impact of perceived meal duration on customer' satisfaction. The third phase compared perceived meal duration and actual meal duration. The last phase suggested appropriate meal duration for maximization of customer' satisfaction. We also examined the effects of meal time (lunch or dinner) on meal duration preferences. Customer satisfaction was decreased with longer perceived meal duration for the order and check stages and too short perceived meal duration for the cook stage. To determine appropriate meal duration for each service stage, the relationship between perceived and actual meal durations was examined. This study confirms that customers dining at restaurants preferred a longer cook time and that a shorter meal duration at dinner decreased satisfaction ratings more when compared to lunch.

• Journal of Preventive Medicine and Public Health
• /
• v.47 no.3
• /
• pp.150-157
• /
• 2014

Objectives: The decrease or increase in sleep duration has recently been recognized as a risk factor for several diseases, including hypertension and obesity. Many studies have explored the relationship of decreased sleep durations and injuries, but few have examined the relationship between increased sleep duration and injury. The objective of this research is to identify the risk for injury associated with both decreased and increased sleep durations. Methods: Data from the 2010 Community Health Survey were used in this study. We conducted logistic regression with average sleep duration as the independent variable, injury as a dependent variable, and controlling for age, sex, occupation, education, region (cities and provinces), smoking, alcohol use, body mass index, hypertension, diabetes, arthritis, and depression. Seven categories of sleep duration were established: ${\leq}4$, 5, 6, 7, 8, 9, and ${\geq}10$ hours. Results: Using 7 hours of sleep as the reference, the adjusted injury risk (odds ratio) for those sleeping a total of ${\leq}4$ h/d was 1.53; 1.28 for 5 hours, for 1.11 for 6 hours, 0.98 for 8 hours, 1.12 for 9 hours, and 1.48 for ${\geq}10$ hours. The difference in risk was statistically significant for each category except for the 8 and 9 hours. In this study, risk increased as the sleep duration decreased or increased, except for the 8 and 9 hours. Conclusions: This research found that either a decrease or increase in sleep duration was associated with an increased risk for injury. The concept of proper sleep duration can be evaluated by its associated injury risk.

• Korean Journal of Child Studies
• /
• v.37 no.3
• /
• pp.13-26
• /
• 2016

Objective: The purpose of this study was to investigate the relationship between sleep duration and school adjustment of elementary-, middle-, high-school youth and to verify the mediating effects of parenting behavior. Methods: We analyzed the data from Wave 4 of the first-grade panel of elementary school and Waves 1 and 4 of the first-grade panel of middle school in Korean Children and Youth Panel Survey (KCYPS), including 1,703 fourth graders, 2,119 seventh graders, and 2,108 tenth graders. Multiple regression was used for the data analyses. Results: The results of this study were as follows. First, longer sleep duration was associated with a higher level of school adjustment in fourth grade. In contrast, longer sleep duration was associated with a lower level of school adjustment in seventh and tenth grades. Second, longer sleep duration was related to a higher level of discipline through reasoning in fourth grade. However, longer sleep duration was related to a lower level of parental monitoring in seventh and tenth grades. Third, the relationship between sleep duration and school adjustment was mediated by parenting behavior. Discipline through reasoning had a mediating effect in fourth grade, but the mediating effect of parental monitoring was found in seventh and tenth grades. Conclusion: These results suggest a differentiated approach on sleep duration in accordance with developmental stage and the need for parent education.

• Korean Journal of Childcare and Education
• /
• v.18 no.6
• /
• pp.75-99
• /
• 2022

Objective: This study aims to explore ways to empirically analyze and manage childcare teachers' job stress based on their relationship with stress-related physiological indicators measured by a fitness tracker. Methods: The study participants were 27 childcare teachers in Gyeonggi-do and wore Garmin's wearable fitness tracker Vivosmart 4 for 15 days for three months. The collected information was analyzed for mean, SD, ANOVA, and correlation using JAMOVI 2.00. Results: First, among the daily changes of physiological indicators measured by a fitness tracker, the data collected on Mondays were significant. On Mondays, the stress index was high, the duration of the rest period was short, and the sleep time was short. The stress of childcare teachers showed a significant negative relationship with the body battery which was calculated by considering the duration of the rest period, heart rate variability, stress, and activity level. Also, the duration of deep sleep was positively correlated with a low degree of stress. There was a significant relationship between the childcare teachers' psychological indicators and the biomarkers measured by fitness trackers. Conclusion/Implications: Stress research using a fitness tracker is big data, and in-depth analysis is possible. Fitness trackers can collect and utilize repeated measurement data for each individual childcare teacher.

• Journal of Korean Academy of Nursing
• /
• v.1 no.1
• /
• pp.49-58
• /
• 1970

For the purpose to clarify the effects of the mothers health during pregnancy on the weight and length of the newborn infants, this study was carried out on 500 new born infants delivered at St, Mary's Hospital, Ewha Woman's University Hospital and Red Cross Hospital in Seoul during the eight-month period from March, 1969 to October, 1969. In this study, the relationship between the T weight and length of the new born infants, and in each case, the weight, length, age, duration of labour, duration of pregnancy, weight gain during pregnancy and diets level during pregnancy of the mother were observed. The relationship between the weight and length of the new born infants and the parity n-as also observed. The results obtained in this study were as follows. 1. The weight of new born infants of both sexes was significantly correlated with the parity, the weight of the mother, and the duration of labour of the primipara. The weight of the mother and the duration of pregnancy were significantly correlated with the weight of the male new born infants only, and the weight of the new born infants and the weight gain of the mother during pregnancy were significantly correlated in the female new born infants. 2. In general, the weight of the new born infants of well or excellently nourished mothers were heavier than those of poorly nourished ones. 3. The length of the new born infants was significantly correlated mother the duration of labour in the primipara.

• Journal of Korea Water Resources Association
• /
• v.37 no.5
• /
• pp.425-435
• /
• 2004

Mainly, observed maximum rainfall has been evaluated by point rainfall, but actually it should be considered by means of average areal rainfall. Average areal rainfall is an estimated value computed through DAD(rainfall Depth-Area-Duration) analysis. By using this value, an average and maximum areal rainfall according to area-duration relationship could be computed. In this study, we assume that the whole Korea region is hydrologically homogeneous, and then analyze using the storm-centered DAD(moving-area DAD) method for the past century data. From this analysis, we evaluate the yearly variation of observed maximum areal rainfall through area-duration relationship. And we also construct an IDF(rainfall Intensity-Duration-Frequency) curve by using the annual time series data which is composed of maximum areal rainfall. The characteristics of IDF and observed maximum areal rainfall is also evaluated.

• Journal of Convergence for Information Technology
• /
• v.12 no.2
• /
• pp.94-106
• /
• 2022

This study was attempted to investigate relationship between level of frailty and sleep duration in the Korean older adults using data from the 8th Korea National Health and Nutrition Examination Survey(KNHANES VIII-1, 2019). The subjects were 1,690, complex sample frequency, descriptive statistics, cross and logistic regression analysis were performed using SPSS program. As a main result, sleep duration simultaneously adjusted for general, health behavior and disease characteristics did not show significant relationship between frail level, but 'not recommended' sleep duration is significantly decreased 70~74 years old, significantly increased lower level of education, lower level of income, and a lot of perceived stress. Finally, personal and social efforts are required to prevent frailty, improve sleep duration of older adults.

• Journal of Korean Public Health Nursing
• /
• v.5 no.2
• /
• pp.53-66
• /
• 1991

The Purpose of this study is to provide the basic data necessary for the high level of nursing service and the efficiency plan of nurse's man power by analyzing job satisfaction level of public health services. The study population included all public health services(118) in health care center within Jeon Buk province. A Survey was conducted to collect data by a self-administered questionnaire from September I to December B, 1990. A Forty item questionnaire was designed to elicit data concerning how nurses feel about the factors of job satisfaction. All the data were analyzed by means of percentage, mean, anova, T-test, Pearsen's correlation coefficient. The Results of this study were summerized as follows. 1. General characteristics of PHN : age: $33.9\%\;20\~29$ years old education level: $52.6\%$ professional nursing college marital status: $75.5\%$ married religion: $50.5\%$ protestant clinical experience: $40.7\%$ no clinical experience public health nursing career: $47.9\%$ low 5years 2. Influencing factor of Job satisfaction desired duration of employment: $65\%$ needed duration, $18.3\%$ lifetime duration motives of employment: $40.8\%$ no special motive of employment desired organ of leave: $19.3\%$ public health clinic 3. Level of job satisfaction with job satisfaction components. The level of job satisfaction showed an average score 3.39 out of 5.0. Job prestige 4.09 was the highest among the components of Job satisfaction and was presented organizational requirement 3.69, Human relationship 3.66, task requirement 3.36, Autonomy 3.10, pay 2.46. 4. Level of job satisfaction with general characteristics. General characteristics(age, educational level, manital status, clinical experience, public health nursing carrier, duties, lincense and qualification) and job satisfaction was no relationship. 5. Level of job satisfaction with Influencing factor. Duration of desired employment (p<0.01) and motives of employment(p<0.001) was presented. 6. Relationship composing factor of job satisfaction and level of job satisfaction 6 components of job satisfaction was related all of job satisfaction. organizational requirement (r=0.93). Autonomy (r=0.93), Human relationship(r=0.92), task requirement (r=0.90), job prestige (r=0.83), pay (r=0.81)