• Journal of the Korean Society of Safety
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• v.27 no.2
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• pp.111-116
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• 2012

This study deals with the traffic accidents of circular intersections in Korea. The purposes are to comparatively analyze the characteristics by operational type, and to develop the models using the data of 82 intersections. In pursuing the above, this study gives particular emphasis to modeling such the accidents as the roundabout and rotary in urban area. The main results analyzed are as follows. First, the null hypotheses that the number of accidents are the same in both the urban and rural intersections, and roundabout and rotary in urban area, were analyzed to be rejected. Second, 3 accident models were developed, which were all statistically significant. The independent variables used in the above models are the ADT, number of approach lane, bus stop, parking facilities, and others. This study could be expected to give some implications to the traffic safety policy decision-making.

• Korean Journal of Community Nutrition
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• v.22 no.6
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• pp.475-484
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• 2017

Objectives: The study was conducted to investigate the relationship between several stress measures in everyday life, emotional eating behavior, and dietary pattern (snacks, fatty foods, sweet beverages, fruits and vegetables) in school-aged children. Methods: One hundred and ninety-four students of an elementary school located in Seongnam City participated in the study. The students responded to the survey questionnaire by self-report, which consisted of items regarding general characteristics, height, weight, dietary habits, frequency of consuming healthy (fruits and vegetables) and unhealthy foods (snacks, fatty foods, and sweet beverages), emotional eating behavior, and daily stress. Correlational analysis was performed to examine the relationship between stress, emotional eating behavior, and dietary pattern, and Poisson and logistic regression analyses were conducted to investigate the effects of stress on dietary pattern. Results: Positive correlations were found between all stress factors and emotional eating behavior and between the friend and personal factor (one of the stress factors) and the consumption of sweet beverages. The frequency of consuming sweet beverages was 2.6 times higher in the high stress group than in the low stress group (95% CI). Conclusions: Children's daily stress was associated with emotional eating behavior and undesirable dietary pattern such as consumption of sweet beverages.

• Korean Security Journal
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• no.51
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• pp.199-219
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• 2017

This research examined the degree to which open-street closed-circuit television (CCTV) systems reduced crime in the vicinity of elementary schools. Information including crime dates, locations, and types around nine elementary schools in the city of Chuncheon in South Korea where the cameras had been installed was gathered and assessed. By employing the Poisson regression with "month" as the unit of analysis and controlling for the days in each month, the average monthly temperatures, and crime trends, the research results show that the CCTV installations had an impact on the reduction of total crime and serious crime. However, the same reduction effect was not observed for disorder crime. Therefore, the results of this study suggest that the employing CCTV is an effective way to control overall crime rates, especially serious crime.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.590-595
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• 2003

An Exponential experiment system which is composed of a neutron detector, a signal analysis system and a neutron source, Cf-252 has been installed in order to experimentally determine the neutron effective multiplication factor for a PWR spent fuel assembly. The axial background neutron flux is measured in a preliminary performance test. From the results, the spacer grid position is determined to be consistent with the design specifications within a 2.3% relative error. The induced fission neutron for four of the assemblies is also measured by scanning the neutron source, Cf-252 or the neutron detector. The exponential decay constants have been evaluated by the application of the Poisson regression to the net induced fission neutron counts. The measured keffs determined on the basis of the exponential decay constants of Cl5 appeared to be 0.541, 0.540, 0.597 and 0.556, respectively, which are comparable with 0.55195$\pm$0.00232 of the MCNP calculation.

• Korean Journal of Health Education and Promotion
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• v.30 no.1
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• pp.41-52
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• 2013

Objectives: Rural-urban differences in suicide have been observed in many settings. However, there has been little research addressing what factors can explain these differences. The purpose of this study was to analyze which compositional factors and contextual factors in local areas might be related to local suicide. Methods: The study design was cross-sectional. The data for 251 primary local governments on their age-standardized suicide mortality and their predefined indicators of compositional factors and contextual factors were obtained from Korean Statistical Information Service as of year 2010. Bivariate analysis including one-way ANOVA and chi-square test were used to identify the differences in local features by area type. Seven poisson regression models for each of total, males, and females were used to analyze which compositional and contextual factors were related to suicide. Results: There were differences in suicide between gu and goon in total, male, and female groups. For total, compositional factors including divorce and smoking rate, and contextual factors including financial independency, water and waterwaste coverage, and number of wastewater discharge factories were found to explain the urban-rural differences. Conclusions: This study provided some evidence that contextual factors at the local level as well as compositional factors are useful for predicting local suicide mortality.

• Safety and Health at Work
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• v.13 no.2
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• pp.201-206
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• 2022

Background: The present objective was to verify whether burnout (emotional exhaustion [EE], depersonalization [DP] and low professional efficacy [PE]) is a risk factor for long-term sickness absence (LTSA; 30 consecutive days) from the teaching role. Methods: This was a prospective cohort study with two years of follow-up that investigated 509 elementary and high-school teachers. Burnout was identified by Maslach Burnout Inventory. Poisson regression with robust variance was used to adjust for possible confounders. Results: The incidence of LTSA was 9.4%. High EE levels were associated with LTSA in the crude analysis, but the association lost statistical significance after adjustments (for sex, age, perception of work-life balance, general self-rated health, chronic pain and depression). High DP levels were associated with this outcome, even after all adjustments (relative risk = 1.80; 95% confidence interval: 1.05-3.09). Low PE levels were not related to LTSA. Conclusion: The results reinforce the need to improve teachers' work conditions to reduce burnout, particularly DP, and its consequences.

• Journal of Korean Society of Transportation
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• v.30 no.6
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• pp.37-46
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• 2012

The number of traffic accidents caused by elderly drivers over the age of 65 has surged over the past ten years from 37,000 to 274,000 cases. The proportion of elderly drivers' accidents has jumped 3.1 times from 1.2% to 3.7% out of all traffic accidents, and traffic safety organizations are pursuing diverse measures to address the situation. Above all, connecting safety measures with an in-depth research on behavioral and physical characteristics of elderly drivers will prove vital. This study conducted an empirical research linking the driving characteristics and traffic accidents by elderly drivers based on the Driving Aptitude Test items and traffic accident data, which enabled the measurement of behavioral characteristics of elderly drivers. In developing the Influence Model, we applied the zero-inflated Poisson (ZIP) regression model and selected an accident prediction model based on the Bayesian Influence in regards to the ZIP regression model and the zero-inflated negative binomial (ZINB) regression model. According to the results of the AAE analysis, the ZIP regression model was more appropriate and it was found that three variables? prediction of velocity, diversion, and cognitive ability? had a relation of influence with traffic accidents caused by elderly drivers.

• Journal of the Korea Concrete Institute
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• v.24 no.4
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• pp.423-433
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• 2012

The axial load on the concrete-filled steel tube (CFT) column produces confinement stress, which enhances strength of the core concrete. The amount of strength increase in concrete depends on the magnitude of produced confinement stress. From nonlinear analyses, the ultimate resisting capacity of the CFT columns subjected to axial loads was calculated. Nonlinear material properties such as Poisson's ratio and stress-strain relation were considered in the suggested model, and the maximum confining stress was obtained by multi axial yield criteria of the steel tube. This proposed model was verified by comparing the analytical results with experimental results. Then, regression analyses were conducted to predict the maximum confining stress according to D/t ratio and material properties without rigorous structural analysis. To ensure the validity of the suggested regression formula, various empirical formulas and Eurocode4 design code were compared.

• Journal of Environmental Health Sciences
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• v.42 no.5
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• pp.324-332
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• 2016

Objectives: The annual average of PM10 in Seoul was $45{\mu}/m^3$, which surpasses the WHO annual guidelines ($20{\mu}/m^3$). Most previous analyses of the effects of PM exposure have been retrospective studies using single hospital data, and fewer studies have attempted to address the relationship of PM10 and hospital costs. This study was conducted to investigate the effects of the concentration of PM10 on hospital visits, admissions and hospital costs in patients with respiratory and cardiovascular diseases. Methods: Medical data from the National Health Insurance Service and the monthly average of PM10 from National Institute of Environmental Research were used to identify the effects of PM10 on hospital visits, admissions and hospital costs. We applied Poisson regression and linear regression to perform the analysis. Results: The relative risks for admissions per $10{\mu}/m^3$ increase in PM10 were 23.11%, 10.2% and 6.9% increases for acute bronchiolitis, asthma and bronchitis, respectively. The relative risk for hospital visits per $10{\mu}/m^3$ increase in PM10 were 10.4%, 6.7% and 5.9% for chronic obstructive pulmonary disease, asthma and chronic sinusitis, respectively. For cardiovascular disease, the relative risk for admissions per $10{\mu}/m^3$ increase in PM10 were 2.2% and 2.1% increases in angina and acute myocardial infarction, respectively. A $10{\mu}/m^3$ increase in the monthly average of PM10 corresponded to 170,723,000 won (95% CI: 125,587,000-215,860,000 won), 123,636,000 won (95% CI: 47,784,000-199,487,000 won) and 78,571,000 won (95% CI: 29,062,000-128,081,000 won) increases in hospital costs for asthma, acute tonsillitis and chronic sinusitis, respectively. Conclusion: Hospital admissions for respiratory and cardiovascular disease were associated with PM10 levels. PM10 exposure is also associated with increased costs for respiratory diseases.

• Environmental Analysis Health and Toxicology
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• v.14 no.1_2
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• pp.21-33
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• 1999

A large number of studies have indicated associations between the impairment of respiratory health and exposure to ambient air pollutants such as ozone (O$_3$) , nitrogen dioxide (NO$_2$) , sulfur dioxide(SO$_2$) , particulate matters (PM$\_$10/). To evaluate this associations, we used the pulmonary function tests (peak expiratory flow rate : PEFR) by mini-wright peak flow meter and counting neutrophils in the nasal lavage (NL) as biomarker. From 15 June to 16 July 1998, for the workers in the highway tollgates, PEFR and NL were measured three times daily and twice per week. and association between the level of air pollutants and PEFR and NL were analyzed using the multiple regression model and the poisson regression model respectively. The results indicated that the effects of all measured air pollutants (SO$_2$, NO$_2$, O$_3$, PM$\_$10/) were not significantly associated with the value of PEFR. On the other side, SO$_2$, NO$_2$, PM$\_$10/ were significantly associated with the number of neutrophils in NL. The increase in SO$_2$, NO$_2$of 10ppb and in PM$\_$10/ of 10$\mu\textrm{g}$/m$^3$was associated with 24%, 21%, 35% increases in neutrophil counts. But the ozone exposure was not associated with NL.