• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.649-655
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• 2010

This study investigated the degradation of phenol using sonication and/or UV-C. The effects of frequency, temperature, pH in solution, argon purging, with UV intensity were estimated in sonication-only, UV-only, and the combined reaction of sonication with UV. The optimum condition for degrading phenol in the sonication-only reaction was 35 kHz, $5^{\circ}C$, and pH 4. As this condition approximately 30% degradation of phenol was achieved within 360 min. However, phenol in the UV-only at $19.3\;mw/cm^2$ under the same condition was completely degraded within 60 min. In the combined system of sonication with UV, the degradation of phenol was well fitted to first-order rate model, and phenol was completely degraded within 360 min and 45 min at UV intensity of $7.6\;mW/cm^2$($17.3{\times}10^{-3}\;min^{-1}$) and $19.3\;mW/cm^2$($138.1{\times}10^{-3}\;min^{-1}$), respectively. Adding methanol, as a radical scavenger, in the phenol degradation in the sonication reaction indicates that OH radical is a major factor in the degradation of phenol. The order of degradation efficiencies of phenol was in the order of as follows; combined reaction of sonication with UV > UV-only > sonication-only.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.2
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• pp.120-125
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• 2015

With rapid urbanization, the volume of traffic in urban area has been significantly increased. This in turn led to problem which can be described as Road Traffic Noise. Currently, to alleviate the road traffic noise damage, a demand for installation of soundproofing walls is rising. Among different shapes of soundproof walls being installed, the reflection-type acoustical insulation panel is highly drawing attentions of residents due to the fact that it does not obstruct their field of vision in contrast with the opaque acoustical insulation panel. On the other hand, improving the soundproofing wall of the reflection-type acoustical insulation barrier panel needs to be focused on since it has a possibility to cause a secondary damage by reflected sounds. Therefore, in this research, study has been carried out to improve the forms in order to minimize travelling of reflected sounds through changing the frontal surface shape and geometrical shape of the reflection-type soundproofing panel. A result from comparison between the normal reflection-type soundproofing panel and the improved soundproofing panel, with reduction effects in the noise reflection, showed that the curved type of soundproofing panel has an impact on reducing the noise up to 1.5 dB. Furthermore, from the research conducted, it appears that the increase and decrease in the reflected sounds can be changeable depending on various design factors. Thus, it turns out that the study shows a potential possibility to develop a reduction technology of the reflected sounds pertaining to overall condition on the soundproofing walls.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.1
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• pp.70-73
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• 2013

Solubility of oil contaminants in surfactant solutions plays an important role in selecting a suitable surfactant type for soil remediation. Solubility measurement procedures consist of making an equilibrium between surfactant solution and oil, solvent extraction using dichloromethane, and condensation for gas chromatography analysis. Solubility measurement requires time consumption and lots of materials. Interfacial tension is the contracting force between two immiscible liquids, surfactant solution and oil, and also closely related to solubility of oil. This study established a relationship between the interfacial tension and solubility of diesel fuel in surfactant solution and suggested a quick method to estimate solubility of oil in a surfactant solution by measuring its interfacial tension. The results of this study showed that the solubility of diesel fuel in surfactant solution was exponentially increased by decreasing the interfacial tension between two immiscible liquids. The solubility of diesel fuel was significantly increased under the interfacial tension conditions below 1 dyne/cm, while the solubility change was not apparent under the interfacial tension conditions beyond 5 dyne/cm. Interfacial tension measurements may allow us to quickly select an efficient surfactant and its concentration for soil remediation.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.306-311
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• 2009

We initially obtained human diseases-related proteins dataset from the OMIM and the SWISS PROT and then constructed disease-related protein-protein interaction network. The protein network contains 40 hub proteins such as CALM1, ACTB and ABL2. The protein network can be derived the map of the relationship between different disease proteins, denoted disease interaction network. We demonstrate that the associations between diseases are directly correlated to their underlying protein-protein interaction networks. From constructed the disease-protein bipartite network, we derived 38 diseasomal proteins, including APP, ABL1 and STAT1. We previously demonstrated that hub proteins in the network tend to be diseasomal proteins in the disease-related protein sub-networks. However, we found that 18% hubs are only diseasomal proteins in the whole disease network. At this point, we could not elucidate difference in the hub-diseasomal proteins tendency between sub0network and whole network. In spite of we still have unsolved problems, our results elucidate that the discovery of protein interaction networks assigned by diseases will provide insight into the underlying molecular mechanisms and biological processes in complex human disease system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.218-225
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• 2016

Recently, Korea has undergone rapid social and economic development, and with that came various changes in living habits and disease patterns; the nation, accordingly, has been alerted to the associated risks of chronic ailments. As risk factors of metabolic syndrome commonly include causal factors of chronic diseases, prevention is important. The prevalence of metabolic syndrome in Korean adults is 22.4%, which comprises a large portion of the whole disease (Korean National Health and Nutrition Examination Survey, 2013). This study aims to examine the elements of healthy living practices by analyzing the risk factors of metabolic syndrome and health behaviors, and provide basic materials to contribute to the activation of health promotion. Among 12,481 subjects of the source data from the 2014 community health survey, which was performed on adults aged 19 and over in Jeonlabuk-do, 12,185 people were analyzed in this study using SPSS 23.0. There were significant differences with respect to sex, smoking status, age, education level, and number of days of physical activity among the results of the difference of the risk factors of the metabolic syndrome according to the characteristics of the health behavior of the subjects. Of the risk factors for metabolic syndrome, this study emphasized the necessity of strategies to promote health programs regarding the management of drinking, smoking, physical activities, depression, subjective health condition and quality of life to the group of those with dyslipidemia, hypertension, and diabetes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.342-352
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• 2018

This study was conducted to evaluate the effects of physical activity practice rates and knowledge related to cardiocerebrovascular disease prevention on the health behavior of middle aged women. Data were collected from Oct to Nov 2017 from 142 middle-aged women living in 24 Eup, Myeon, and Dong areas in North Gyeongsangbuk-do Province using a structured questionnaire. The obtained data were analyzed using descriptive statistics, t-tests, ANOVA, Pearson's correlation, and stepwise multiple regression analysis. The major factors influencing health behavior were found to be alcohol consumption (${\beta}=0.15$, p=0.009), diet (${\beta}=0.16$, p=0.003), vigorous intensity (${\beta}=0.14$, p=0.011), marriage (${\beta}=0.19$, p<0.001), interest in one's own health (${\beta}=0.23$, p<0.001), and health recognition (ill: ${\beta}=0.31$, p<0.001). Alcohol consumption and diet were factors of cardiocerebrovascular knowledge, vigorous intensity was a factor of physical activity practice rate, marriage and interest in one's own health were factors of general characteristics, and health recognition was a factor in health-related characteristics. Health-promotion activity was positively correlated with knowledge regarding cardiocerebrovascular disease prevention (r=0.41, p<0.001) and physical activity practice rate (r=0.44, p<0.001). It will be necessary to develop and apply practical intervention programs based on disease prevention knowledge and physical activity to enhance the health behavior of middle aged women.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.2
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• pp.141-153
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• 2014

This study is about the development of cholesteric liquid crystals (CLCs), which are highly applicable to cosmetics formulation. The CLCs made from non-animal origin were chosen not only because they are free of animal viruses but also because they give a sense of security to the cosmetic consumers. Three kinds of new cholesteric derivatives (CI, CC, CN) were synthesized using non-animal cholesterol [NAB cholesterol (ARCH LONZA)], which was originally made by fermentation process. To develop high applicability to cosmetics formulation, we attempted to find out the optimum compositions in which CLCs can maintain their color over a wide range of temperature. The CLCs in 41 different compositions were prepared by the combinations of three cholesteric derivatives and a visual evaluation method was employed to determine the range of temperature at which the CLCs display their color. The 205 UV-VIS spectral data obtained from 41 CLCs at various temperatures were simultaneously analyzed to investigate the critical factors affecting the characteristics of the CLCs. Results showed that A4, A5, A6 and A7 were the best compositions to cosmetics formulation. A6 composition had a great moisturizing effect by the artificial skin test ($AmoReSkin^{TM}$).

• Journal of Korean Society of Steel Construction
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• v.28 no.3
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• pp.195-202
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• 2016

In this study, it is carried out to analyze the international design standards such as Eurocode 8, API 650, NZSEE and etc for the seismic design of steel liquid storage tanks. From the comparison and analysis, the data for the required parameters and factors are provided for the establishment of Korean seismic design standard for steel liquid storage tanks. The simplified mechanical models have been presented for the seismic design of steel liquid storage tanks in all design standards and the parameters of mechanical models in design standards have similar values. Although the models for the seismic design of steel liquid storage tanks are similar in design standards, design approaches are given differently in accordance with the design methods, allowable stress design or limit state design. Therefore it is not easy to compare seismic forces presented in design standards directly. After comparison of design standards, it is concluded that establishment of Korean design standard for the seismic design of steel liquid storage tanks is necessary.

• Nuclear Engineering and Technology
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• v.26 no.3
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• pp.440-452
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• 1994

Nuclear fuel bundles are designed such that the heat flux at a-fuel pin surface should not exceed the critical heat flux (CHF) during normal operation and anticipated transient. Therefore, evaluation of the CHF for fuel bundle is demanded in an exact and reliable manner. One of the major concerns with the current application of CHF correlations is that the CHF based on circular tubes is applied to the fuel bundle subchannel analysis, mainly in terms of the hydraulic diameter with correction factors which may result in a source of possibly large uncertainties in CHF prediction. The hydraulic diameter does not recognize the local properties of fluid nor such effect as the surface curvature; the turbulence action on the convex surface is much more pronounced than that on the concave surface. Even for the tube having concave curvature, the effect of tube diameter on CHF becomes important with decreasing diameter. These facts imply that the convex curvature effect is significant and crucial to the reliable CHF prediction. This paper reviews and discusses analytical and experimental aspects of effect of transverse convex curvature in incompressible turbulent flow and heat transfer, and on CHF. Flow models to quantify this effect are briefly mentioned and future works are recommended.

• Journal of the Korean Wood Science and Technology
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• v.41 no.1
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• pp.42-50
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• 2013

Since 1990's, a plywood for flooring base has gotten customers' demand. Costs of raw material and production increased because of changed environment of industry. Tropical timber such as Red Meranti (Shorea acuminate) used for raw material of the floor has been depleting beside countries in South Eastern Asia changed species of afforestation. As a result, it gets hard to secure good quality of raw material for plywood. Moreover plywood price is increased suddenly after earthquake in Japan. Eucalyptus (Eucalyptus globulus) in china has been using for raw material as a countermeasure of changed environment of industry. In this study, possibility of using flooring consisted of Eucalyptus veneer as crossband layers was checked by deflection experiments. Flooring consisted of Red Meranti was used for comparison. Two factors which impact on deflection are a type of density gradient and density difference between Long-grain veneer and Short-grain veneer. Red Meranti samples are M type of density gradient on the other hand Eucalyptus samples are W type of density gradient. The more samples have high density difference, the more deformation was checked. A sample which has big density difference between core and cross bands layer warp more also deform. Flooring was deformed smaller than plywood and samples which have big density difference was deformed more.