• Journal of Korean Society on Water Environment
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• v.25 no.4
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• pp.507-514
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• 2009

In this study, a dynamic modeling scheme is presented to describe the probabilistic structure of soil water and plant water stress index under stochastic precipitation conditions. The proposed model has the form of the Fokker-Planck equation, and its applicability as a model for the probabilistic evolution of the soil water and plant water stress index is investigated under a climate change scenario. The simulation results of soil water confirm that the proposed soil water model can properly reproduce the observations and show that the soil water behaves with consistent cycle based on the precipitation pattern. The simulation results of plant water stress index show two different PDF patterns according to the precipitation. The simple impact assessment of climate change to soil water and plant water stress is discussed with Korean Meteorological Administration regional climate model.

• Journal of Environmental Health Sciences
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• v.34 no.2
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• pp.117-123
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• 2008

Allergic diseases have been dramarically increased over recent years, especially in industrialized countries. Oxidative stress has been believed to playa significant role in the occurrence of the allergic inflammatory responses. Although previous studies concerning oxidative stress and systemic inflammation have been reported, few data is available, and other allergic diseases, except for asthma, are hardly studied about the association with oxidative stress. This study evaluated the relationship between allergic disease and Malondialdehyde (MDA) as an indicator of oxidative stress. The study population was 197 male adults living in an industrial area. The ISAAC questionnaire was used to confirm wheezing and rhinitis, and atopy was evaluated by skin prick test. MDA was analyzed by spectrophotometer. To examine bronchial hyperresponsiveness (BHR), methacholine test was performed, and the index of bronchial responsiveness (BR index) was calculated. We used multivariate logistic regression model and general linear model with SAS program. We found significant associations of MDA with brindex (p=0.023), rhinitis (p=0.016), atopy (p=0.03), adjusted by age, smoking, and body mass index (BMI). On the contrary, there was no significant difference of MDA with the status of asthma. Our result suggests that oxidative stress may playa major role in the occurrence of allergic response in male adults.

• Journal of Environmental Health Sciences
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• v.42 no.2
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• pp.85-91
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• 2016

Objectives: The objective of this study was to assess heat stress, compare heat stress indices, and evaluate the usefulness of wet bulb globe temperature (WBGT) among outdoor workers exposed to heat during the summer season. Methods: WBGT, dry temperature, and heat index were measured using WBGT measurers (QUESTemp 32 model and QUESTemp 34 model, QUEST, WI, USA) by industrial hygienists from August 27 to September 16, 2015. Heat stress indices were measured at the workplaces of a shipbuilder in Ulsan and a construction site in Daegu. The dry temperature observed by the Automated Synoptic Observing System (ASOS) of the Korea Meteorological Administration was also compared. Results: Dry temperature measured by WBGT is different from that by ASOS. The temperature obtained from ASOS was less than $33^{\circ}C$, above which point a heat wave is forecast by the Korea Meteorological Administration. A heat index above $32.8^{\circ}C$ as a moderate risk was not observed during measurement. WBGT was consistently higher than $22^{\circ}C$, above which the risk of heat-related illness is increased in unacclimated workers involved in work with a high metabolic rate. WBGT was sometimes higher than $28^{\circ}C$, above which the risk of heat-related illness is increased in acclimated workers involved in work with a moderate metabolic rate in September. Conclusion: According to the measurement of heat stress indices, WBGT was more sensitive than heat index and temperature. Thus, general measures to prevent heat-related diseases should be implemented in workplaces during the summer season according to WBGT.

• Journal of Navigation and Port Research
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• v.27 no.5
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• pp.479-486
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• 2003

The concept of “Environmental Stress(ES)” can be used as a useful index when assessing the maritime traffic safety. It is composed of two parts, one due to geographical restriction and another one due to traffic congestion. In this paper, Environmental Stress due to geographical restriction is reviewed Its characteristics are surveyed from the sample calculation results for some hypothetical cases, such as approaching a breakwater, navigating in a long straight channel, and in a long bended channel. Sample calculations are also carried out for the approach channels in Busan and Kwangyang harbor. By using this ES concept, it is expected that objective ana quantitative assessment of safety is possible for various environmental conditions when navigating in a harbor or in a fairway.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2003.05a
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• pp.198-205
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• 2003

The concept “Environmental Stress(ES)” can be used as a useful index when assessing the maritime traffic safety. It is composed of two parts, one due to geographical restriction and another one due to traffic congestion. In this paper, Environmental Stress due to geographical restriction is reviewed. Its characteristics are surveyed from the sample calculation results for some hypothetical cases, such as approaching a breakwater, navigating in a long straight channel, and in a long bended channel. Sample calculations are also carried out for the approach channels in Busan and Kwangyang harbor. By using this ES concept. it is expected that objective and quantitative assessment of safety is possible for various environmental conditions when navigating in a harbor or in a fairway.

• Environmental Analysis Health and Toxicology
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• v.26
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• pp.9.1-9.9
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• 2011

Objectives: In order to evaluate which temperature index is the best predictor for the health impact assessment of heat stress in Korea, several indexes were compared. Methods: We adopted temperature, perceived temperature (PT), and apparent temperature (AT), as a heat stress index, and changes in the risk of death for Seoul and Daegu were estimated with $^1{\circ}C$ increases in those temperature indexes using generalized additive model (GAM) adjusted for the non-temperature related factors: time trends, seasonality, and air pollution. The estimated excess mortality and Akaike's Information Criterion (AIC) due to the increased temperature indexes for the $75^{th}$ percentile in the summers from 2001 to 2008 were compared and analyzed to define the best predictor. Results: For Seoul, all-cause mortality presented the highest percent increase (2.99% [95% CI, 2.43 to 3.54%]) in maximum temperature while AIC showed the lowest value when the all-cause daily death counts were fitted with the maximum PT for the $75^{th}$ percentile of summer. For Daegu, all-cause mortality presented the greatest percent increase (3.52% [95% CI, 2.23 to 4.80%]) in minimum temperature and AIC showed the lowest value in maximum temperature. No lag effect was found in the association between temperature and mortality for Seoul, whereas for Daegu one-day lag effect was noted. Conclusions: There was no one temperature measure that was superior to the others in summer. To adopt an appropriate temperature index, regional meteorological characteristics and the disease status of population should be considered.

• The Journal of Korean Academic Society of Nursing Education
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• v.8 no.1
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• pp.61-71
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• 2002

purpose : The purpose of this study was to find out the influencing factors of smoking-cessation behavior of patients with coronary heart disease and to suggest the model of smoking-cessation behavior which was based on the relationship between influencing factors and then to test its fitness empirically. method : This study was based on the Theory of Reasoned Action and a hypothetical model was constructed with fifteen paths in consideration of main predictive factors of smoking-cessation behavior such as biological factor, disease-related characteristics, self-efficacy, supportive factor, environmental factor, disease-related perception factor, intention-to-quit, and psychological factor. The validity of a smoking- cessation model was tested to 264 patients with coronary heart disease by using SPSS 8.0 and Window LISREL 8.12a. results : 1. Seven of the 15 paths of smoking-cessation behavior proved to be significant. 2. The final model excluded three paths in the hypothetical model was demonstrated to be improved by $x^2$=44.31 (df=38, p=.22), Goodness of Fit Index (GFI)=.98, Adjusted Goodness of Fit Index (AGFI)=.96, Non-Normed Fit Index(NNFI)=1.00, Normed Fit Index(NFI)=1.00, and Root Mean Square Residual(RMR)=.24. 3.The smoking-cessation behavior was influenced directly by biological factor, self-efficacy, supportive factor, environmental factor, intention-to-quit, and psychological factor. The smoking-cessation behavior was accounted for 82% of variance by these factors. conclusion : although the adolescents' smoking behavior can be predicted by only smoking intention, it is hard to predict the adults' smoking-cessation behavior by only this factor. Therefore, intention-to-quit, self-efficacy, supportive factor should be improved because these are promotive factors for smoking-cessation behavior. Biological factor, environmental factor, and psychological factor are inhibitive factors, so nicotine replacement therapy is helpful to the high nicotine-dependents, and ex-smokers avoid other smokers in their environment and also patients should learn and practice the stress coping-skills.

• Ocean and Polar Research
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• v.30 no.1
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• pp.109-117
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• 2008

Application of biomarkers for assessing marine environmental health risk is a relatively new field. According to the National Research Council and the World Health Organization, biomarkers can be divided into three classes: biomarkers of exposure, biomarkers of effect, and biomarkers of susceptibility. In order to assess exposure to or effect of the environmental pollutants on marine ecosystem, the following set of biomarkers can be examined: detoxification, oxidative stress, biotransformation products, stress responses, apoptosis, physiological metabolisms, neuromuscular responses, reproductions, steroid hormones, antioxidants, genetic modifications. Since early 1990s, several biomarker research groups have developed health indices of marine organisms to be used for assessing the state of the marine environment. Biomarker indices can be used to interpret data obtained from monitoring biological effects. In this review, we will summarize Health assessment Index, Biomarker Index, Bioeffect Assessment Index and Generalized Linear Model. Measurements of biomarker responses and development of biomarker index in marine organisms from contaminated sites offer great a lot of information, which can be used in environmental monitoring programs, designed for various aspects of ecosystem risk assessment.

• Journal of Environmental Science International
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• v.23 no.11
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• pp.1929-1941
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• 2014

Now a days, frequency of abnormally high temperatures like heat wave by global warming and climate change is increasing constantly and the number of patient with heat related illness are jumping rapidly. In this study, we chose the case day for the heat wave in Busan area(Busan and Yangsan), 2013 which it was the most hottest year during 21th century. And then, we analysed the weather condition using automatic synoptic observing system(ASOS) data. Also, four indices, heat index(HI), wet bulb globe temperature(WBGT), Man-ENvironment heat EXchange model(MENEX)'s results like Physiological subjective temperature(PST), Physiological strain(PhS), were calculated to evaluate the thermal comfort and stress quantitatively. However, thermal comfort was different as the each station and thermal comfort index during same time. Busan's thermal indices (HI: hot, WBGT: sweltering, PST: very hot, PhS: very hot) indicated relatively higher than Yansan's (HI: very hot, WBGT: sweltering, PST: very hot, PhS: sweltering). It shows that Busan near coast is relatively more comfortable than Yangsan located in inland.

• Structural Engineering and Mechanics
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• v.22 no.2
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• pp.223-240
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• 2006

Taking into account the geometrical and material nonlinearities, an ultimate behavior of reinforced concrete cooling tower shell in hyperbolic configuration is presented. The design wind pressures suggested in the guidelines of the US (ACI) and Germany (VGB), with or without the effect of internal suction, are employed in the analysis to examine the qualitative and quantitative characteristics of each design wind pressure. The geometrical nonlinearity is incorporated by the Green-Lagrange strain tensor. The nonlinear features of concrete, such as the nonlinear stress-strain relation in compression, the tensile cracking with the smeared crack model, an effect of tension stiffening, are taken into account. The biaxial stress state in concrete is represented by an improved work-hardening plasticity model. From the perspective of quality of wind pressures, the two guidelines are determined as highly correlated each other. Through the extensive analysis on the Niederaussem cooling tower in Germany, not only the ultimate load is determined but also the mechanism of failure, distribution of cracks, damage processes, stress redistributions, and mean crack width are examined.