• Journal of Radiation Protection and Research
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• v.33 no.1
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• pp.27-34
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• 2008

A Korean urban contamination model METRO-K (${\underline{M}}odel$ for ${\underline{E}}stimates$ the ${\underline{T}}ransient$ Behavior of ${\underline{R}}adi{\underline{O}}active$ Materials in the ${\underline{K}}orean$ Urban Environment, which is capable of calculating the exposure doses resulting from radioactive contamination in an urban environment, is taking part in a model testing program EMRAS (${\underline{E}}nvironmental$ ${\underline{M}}odelling$ for ${\underline{RA}}diation$ ${\underline{S}}afety$) oragnized by the IAEA (${\underline{I}}nternational$ ${\underline{A}}tomic$ ${\underline{E}}nergy$ ${\underline{A}}gency$). For radioactive contamination scenarios of Pripyat districts and a hypothetical RDD (${\underline{R}}adiological$ ${\underline{D}}ispersal$ ${\underline{D}}evice$), the predicted results using METRO-K were submitted to the EMRAS's Urban Contamination Working Group. In this paper, the predicted results for the contamination scenarios of a Pripyat district were shown in case of both without remediation measures and with ones. Comparing with the predictied results of the models that have taken part in EMRAS program, a feasibility for decision-making support of METRO-K was investigated. As a predicted result of METRO-K, to take immediately remediation measures following a radioactive contamination, if possible, might be one of the best ways to reduce exposure dose. It was found that the discrepancies of predicted results among the models are resulted from 1) modeling approaches and applied parameter values, 2) exposure pathways which are considered in models, 3) assumptions of assessor such as contamination surfaces which might affect to an exposure receptor and their sizes, 4) parameter values which are related with remediation measures applied through literature survey. It was indentified that a Korean urban contamination model METRO-K is a useful tool for dicision-making support through the participation of EMRAS program.

• Child Health Nursing Research
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• v.19 no.2
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• pp.85-93
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• 2013

Purpose: The study purposes were to describe the process of developing the Korean versions of the Six Dimension Scale of Nursing Performance (Six-D) and Student Nurse Stress Index (SNSI) and psychometric evaluation of the two measurements. Methods: This was a methodology study using a descriptive cross-sectional design with 51 nursing students in 4th year of university. Internal consistency reliability was assessed using Cronbach alphas. Construct validity was determined by exploring correlations among Six-D, SNSI, objective structured clinical examination (OSCE), self-efficacy and grade point average (GPA). Results: Internal consistency reliability of Six-D and SNSI was acceptable with Cronbach's ${\alpha}$ of .95 and .82. Correlation analysis to determine construct validity revealed that Six-D presented positive correlations with OSCE (r=.109~.272) and self-efficacy (r=.005~.161) and negative correlation with GPA (r=-.246~-.394), although all were not statistically significant. SNSI presented all negative correlations with OSCE (r= -.007~-.238), self-efficacy (r=-.246~-.394), and GPA (r=-.092~-.426) and were mostly statistically significant except OSCE. Conclusion: Six-D needs more evidence to confirm validity to predict observed clinical competency and theoretical relationships with self-efficacy and GPA. However, SNSI presented trends of expected relationships with relevant variables. Therefore, further research is recommended in testing validity of Six-D with other student populations.

• Korean Chemical Engineering Research
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• v.40 no.6
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• pp.769-777
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• 2002

Using four components - nonionic surfactants, water, hydrocarbon oil and an alcohol as cosurfactant, 12 types of cleaning agents were prepared, and their physical properties such as surface tension, viscosity, electroconductivity and phase stability were measured. As the formulated cleaning agents have low surface tensions(30.5-31.1 dyne/cm) and low viscosities (1.6-7.2 c.p.), they are satisfied with the general physical properties of water-in-oil(W/O) microemulsions for their industrial use. They showed a tendency that their temperature range for stable one-phase microemulsion decreased in accordance with the increase of alcohol/surfactant(A/S) ratio in the formulations. However, the temperature range of one-phase microemulsion was much more affected by hydrophilic lipophillic balance(HLB) value of the nonionic surfactant which increased its temperature range and it increased in accordance with the higher HLB value in the formulations. And the maximum content of water which can keep stable one-phase W/O microemulsion was measured at each sample. In addition, their temperature range for stable one-phase microemulsion was also measured. It was confirmed that the selection of surfactant type was very important for formulating a cleaning agent, since the W/O microemulsion system with the nonionic surfactant of the lower HLB value showed better cleaning efficacy that of the higher HLB value for abietic acid as a soil, which was used for preparing a rosin-type flux. In the formulated cleaning agents with the increase of A/S ratio in the formulations, however, there was no significant difference in cleaning efficacy. It was investigated that the differences of their cleaning efficacy was affected by the change of the condition of temperature and sonicating frequency as important factors in the industrial cleaning. That is, the higher, their cleaning temperature and the lower, their sonicating frequency, the more increased, their cleaning efficacy. Furthermore, using optical instruments like UV/Visable Spectrophotometer and FT-IR Spectrometer, their cleaning efficacy for abietic acid was measured. The removal of soil from the contaminated rinse water was measured by gravity separation method in the rinse bath. As a result, the cleaning agent system having the nonionic surfactant of HLB value 6.4 showed over 85% water-oil separation efficacy at over $25^{\circ}C$. Therefore, it was demonstrated in this work that the formulating cleaning agents were very effective for cleaning and economical in the possible introduction of water recycling system.

• Korean Journal of Psychosomatic Medicine
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• v.8 no.1
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• pp.46-57
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• 2000

Objectives : The purpose of the present study was to examine the effect of subacute treatment with the selective serotonin reuptake inhibitors(paroxetine and sertraline) on immobility in the forced swim test(FST) and on FST-induced changes in immune parameters of the mice. Methods : Authors applied a modified method of FST by Porsolt et al. Over 5 BALB/c mice were used for each group of experiments. To explore the changes in immune parameters by FST, authors investigated the production of anti-rat RBC antibody, concanavalin A(ConA)- or lipopolysaccharide(LPS)-stimulated splenocytes proliferation assay and cytokine gene expression. Results : Both paroxetine and sertraline decreased the duration of immobility in a dose-related manner. FST-performed mice showed a significant decrease in mitogenic responses of splenocytes and a slight increasing tendency in anti-rat RBC antibody response. All these responses were attenuated significantly by paroxetine and attenuated nearly nominal significance level by sertraline. The cytokine profiles of ConA-stimulated splenocytes from FST-performed mice showed stronger expression of IL-4 and weaker expression of IL-2 than control mice, and no changes in the expressions of IFN-$\gamma$ and lymphotoxin. IL-6 and IL-10 were not expressed in both group of mice. The pretreatment of paroxetine and sertraline attenuated the altered cytokine expressions in FST-performed mice to some extent. Some alterations of the expressions of IL-6 and IL-10 were observed in the mice which the selective serotonin reuptake inhibitors had been pretreated. Conclusion : The subacute treatment of paroxetine and sertraline attenuated the FST-induced behavioral and immune changes, and these serotonin reuptake inhibitors may exert some modulating effects on the immune system by the induction of cytokine gene expression, especially IL-6 and IL-10.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.6
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• pp.148-161
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• 2016

In the case of the government, which plays a pivotal role in the landscape architecture system, the management of positions in landscape architectural organizations is lacking. At the local government level, while public officials for managing landscape architecture are being hired, there are problems and vulnerabilities in both management and system operations as such public officials recruited for positions in landscape architectural services operate under the forestry service. Accordingly, this study analyzed the Korean administrative system of public officials in the landscape architectural service and their satisfaction with the organizational culture and behavior. The aim was to provide practical data for improving the job satisfaction of public officials in landscape architectural service and enhance the status of landscape architecture. First, a survey was conducted regarding current organizational culture/behavior and job adequacy, and differences when compared to different job series with regards to the public officials in the landscape architectural service. The results indicated that job satisfaction of those in landscape architectural service was generally high, but they showed strong centralization, i.e., orders from superiors and limitations on autonomy. Second, an analysis was conducted to improve the organizational culture/behavior and job satisfaction of public officials in the landscape architectural service, and a comparative analysis was conducted on the differences between the analysis result and preceding studies by the Ministry of Government Administration and Home Affairs(2006). The results indicated that organizational commitment/satisfaction of public officials in the landscape architectural service was relatively low among those who had a great amount of work experience related to forestry. Therefore, it was shown that it is necessary to ensure expertise in landscape architecture. Third, a comprehensive analysis was conducted regarding the influences on "working environment", "legal system" and "job allocation" in regard to public officials in land architectural service. The results indicated that satisfaction in the value system was high when given significance to the job as public officials in land architectural. However, their satisfaction in the land architectural system was low due to the lack of independence in their positions, the vulnerable legal system of land architectural service and low employment rates. Fourth, current public officials in landscape architectural service process tasks such as forestry, architecture, city planning and administration that are not related to their area of expertise. Therefore, an analysis was conducted on whether there is a difference in the job satisfaction of public officials in landscape architectural service according to statistical variables. It was identified that "legal system", "job satisfaction" and "organizational commitment" with regard to public officials in landscape architectural service can be improved through ensuring their expertise. This study suggests the following tasks to further inquire into landscape architecture in general. First, establish an identity of work allocation for public officials in the landscape architectural service, and second, establish an organizational constitution according to the positions in landscape architectural service. Accordingly, it is necessary for interested parties of landscape architecture to devise practical strategies so that such tasks can be converged administratively and reflected in policies.

• Fire Science and Engineering
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• v.17 no.4
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• pp.76-85
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• 2003

In this study, we write down the definitions, their causes and the techniques of analysis as a theoretical consideration of common cause failures, and investigate the limitation and the importance of the common cause failures by applying to the analysis on the fire protection as a representative safety facility. As you can know in the reliability analysis, most impressive cause is the malfunctions of pumping operations; especially the common cause failure of two pumps is dominant. In other words, it is possible to assess system-reliability as twice as actual without CCF From these, CCF is extraordinarily important and the results are highly dependent on the CCF factor. And although it would increase with multiple installations, the reliability are not defined as linear with those multiplications. In addition, the differences in results due to the models for analysis are not significant, whereas the various sources of data produce highly different results. Therefore, we conclude that the reliabilities are dependent on the quality of the usable data much better than the variety of models. As a result, the basic and engineering device for the preventions of CCF of the multiple facilities is to design it as reliably as to design the fire-water pump. That is to say, we must assess those reliabilities using PFD whether they are appropriate to SIL (Safety Integrity Level) which is required for the reliability in SIS (Safety Instrumented System). The result of the analysis on the reliability of the fire-water supply with CCF shows that PFD is 3.80E-3, so that it cannot be said to be designed as safely as in the level of SIL5. However, without CCF, PFD is 1.82E-3 which means that they are designed as unsafely as before.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.4
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• pp.71-80
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• 2009

Although desire for living without hazardous damages grows these days, threats from natural disasters which we are currently exposed to are quiet different from what we have experienced. To cope with this changing situation, it is necessary to assess the characteristics of the natural disasters. Therefore, the main purpose of this research is to suggest a methodology to estimate the potential property loss and assess the flood risk using a regional regression analysis. Since the flood damage mainly consists of loss of lives and property damages, it is reasonable to express the results of a flood risk assessment with the loss of lives and the property damages that are vulnerable to flood. The regional regression analysis has been commonly used to find relationships between regional characteristics of a watershed and parameters of rainfall-runoff models or probability distribution models. In our research, however, this model is applied to estimate the potential flood damage as follows; 1) a nonlinear model between the flood damage and the hourly rainfall is found in gauged regions which have sufficient damage and rainfall data, and 2) a regression model is developed from the relationship between the coefficients of the nonlinear models and socio-economic indicators in the gauged regions. This method enables us to quantitatively analyze the impact of the regional indicators on the flood damage and to estimate the damage through the application of the regional regression model to ungauged regions which do not have sufficient data. Moreover the flood risk map is developed by Flood Vulnerability Index (FVI) which is equal to the ratio of the estimated flood damage to the total regional property. Comparing the results of this research with Potential Flood Damage (PFD) reported in the Long-term Korea National Water Resources Plan, the exports' mistaken opinions could affect the weighting procedure of PFD, but the proposed approach based on the regional regression would overcome the drawback of PFD. It was found that FVI is highly correlated with the past damage, while PFD does not reflect the regional vulnerabilities.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.2
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• pp.165-174
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• 2010

The numerical modeling of a coal gasification reaction occurring in an entrained flow coal gasifier is presented in this study. The purposes of this study are to develop a reliable evaluation method of coal gasifier not only for the basic design but also further system operation optimization using a CFD(Computational Fluid Dynamics) method. The coal gasification reaction consists of a series of reaction processes such as water evaporation, coal devolatilization, heterogeneous char reactions, and coal-off gaseous reaction in two-phase, turbulent and radiation participating media. Both numerical and experimental studies are made for the 1.0 ton/day entrained flow coal gasifier installed in the Korea Institute of Energy Research (KIER). The comprehensive computer program in this study is made basically using commercial CFD program by implementing several subroutines necessary for gasification process, which include Eddy-Breakup model together with the harmonic mean approach for turbulent reaction. Further Lagrangian approach in particle trajectory is adopted with the consideration of turbulent effect caused by the non-linearity of drag force, etc. The program developed is successfully evaluated against experimental data such as profiles of temperature and gaseous species concentration together with the cold gas efficiency. Further intensive investigation has been made in terms of the size distribution of pulverized coal particle, the slurry concentration, and the design parameters of gasifier. These parameters considered in this study are compared and evaluated each other through the calculated syngas production rate and cold gas efficiency, appearing to directly affect gasification performance. Considering the complexity of entrained coal gasification, even if the results of this study looks physically reasonable and consistent in parametric study, more efforts of elaborating modeling together with the systematic evaluation against experimental data are necessary for the development of an reliable design tool using CFD method.

• Journal of Korean Society of Forest Science
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• v.78 no.3
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• pp.314-322
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• 1989

For the improvement of nursery condition and the study of eco-physiological characteristics of Pinus koraiensis(2-2) seedlings, the primary productivity was investigated and the growth characteristics and their correlationship were analyzed from May to September in 1987. Seedlings used in this study were grown at the nursery of Experimental Forestry of Kyung Hee Univ. The installation of experimental plots were divided into control plot (100%), 63%, 37% and 19% relative light intensity, and each relative light intensity plots were split into $15{\times}15/m^2$, $12{\times}12/m^2$, $9{\times}9/m^2$ and $6{\times}6/m^2$ plnting density by randomized black design method. To take into account the edge effect of plant population, material were selected from each plot by random sampling at 30 days interval. Each sampled material was divided into leaf and stem drived in a drying oven at the temperature of $85^{\circ}C$ until it had constant weight and weighed. and leaf area was surveyed. Growth analysis for RGR and NAR was done by Blackman method and correlation coefficient were investigated between RGR and NAR by analyzing the dry matter production and growth characteristics of the material, cultivated on the experimental nursery under the condition of different treatment the obtained result were as follows : 1. The increasing rate of dry matter was similar at early stage of growth, but not at late stage. 2. Leaf area growth was the maximum value at 63% relative light intensity and the minimum at 19% RLI 3. The value of RGR was the highest on June under $6{\times}6/m^2$ planting density in 63% relative light intensity, the lowest on September under $12{\times}12/m^2$ of 19% relative light intensity. 4. The change NAR decreased in early stage of growth, while it increased on August and September, The value of RGR on June under $6{\times}6/m^2$ planting density in 100 light intensity was the highest, and on September under $12{\times}12/m^2$ planting density in 19% relative light intensity was the lowest. 5. Regression and correlation between RGR and NAR showed significantly positive.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.849-858
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• 2007

This study was intended to collect the baseline information on health status, nutrient intakes and dietary self-efficacy according to the obesity levels of male workers. Nutrient intakes of 224 male workers were assessed by 24 hr recall method; also, dietary attitude and dietary self-efficacy were investigated by self-administerd questionnaires. Biochemical characteristics such as blood pressure (SBP, DBP), total cholesterol(TC), hemoglobin (Hb), blood glucose (BG), SGOT, SGPT and ${\gamma}-GTP$ were assessed. Subjects were divided into normal, overweight and obese groups by body mass index (BMI). The health status was analyzed as normal group, health concerned group and disease suspected group. Weight, percent ideal body weight (PIBW), BMI and body circumference (waist, hip) and waist-hip ratio were high in the order of obese group, overweight group and normal group. Body fat mass was high also in the order of obese, overweight and normal group. Blood pressure (SBP, DBP) was the highest in obese group. SGOT, SGPT, ${\gamma}-GTP$ were higher in the obese group than normal and overweight groups. It was Proven that the percentage of those evaluated as low nutrient intakes were 71% for Ca, 50.9% for Zn, 70.5% for vitamin B2, 56.3% for vitamin C and 81.3% for folic acid. The dietary attitude scores were high according to the dietary self-efficacy. The age was positively correlated with dietary attitude, and the dietary attitude was positively correlated with dietary self-efficacy and total energy intakes. Dietary attitude showed the greatest total causal effect in relation to dietary self-efficacy. The results of this study showed some health problems and nutritional problems, indicating the need for nutritional management for male workers.