• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.34-42
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• 2002

This research was carried out to investigate water repellent effectiveness of natural oil treated wood. Linseed oil, castor oil, olive oil, bean oil, perilla oil and sunflower oil were used in this test. For evaluation of water repellent of natural oil treated wood, moisture absorption test, water-drop contact angle test and color difference test of accelerated decomposition by UV and water were used. The moisture absorption amount of natural oil treated wood was less than untreated wood until 3 hours, but it was increased with time, there was no big difference with oil treated wood and untreated wood after 48hours. Oil treated wood and untreated wood showed big difference on contact angle test. It was no big difference by kind and oil concentration. Natural oil treated wood did not showed stability on the weather aging test. Contact angle test could be used on evaluation of wood surface status treated with natural oil.

• Journal of Korea Port Economic Association
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• v.34 no.2
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• pp.51-68
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• 2018

This paper compares the differences in management performance in the logistics market and analyzes the differences in business characteristics depending on the industry types. In addition, the effects of industry types and business characteristics on management performance are examined. The analysis method used is ANOVA and K-means clustering. The implication of the study are as follows. First, in the logistics market in Japan, there was a difference in management performance among the types of industry. The warehousing service type had the highest profitability and stability among all the industry types. Second, differences in business characteristics by industry types were tested. It was found that offshore cargo transportation type was more capital intensive than the other types. In addition, warehousing service type had higher business leadership and credit transaction than others. Third, industry types and clusters based on business characteristics had a significant impact on management performance through interaction effects. For the profitability variables in detail, other clusters had a significant effect between transportation types(onshore and offshore cargo) and warehousing service type. On the other hand, in stability variables, one cluster was effective in all types, which is a characteristic that lowers both capital intensity and business leadership.

• 한국체육학회지인문사회과학편
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• v.57 no.2
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• pp.509-518
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• 2018

The purpose of this study was to examine the association between resting heart rate (RHR) and the prevalence of colorectal cancer in Korean adults. A cross sectional analysis was performed using the Korea National Health and Nutrition Examination Survey (2005 to 2014). Total number of subjects were 10,564 adults aged over 19 years. The results showed that individuals in the highest quartile of RHR had a significantly higher prevalence of colorectal cancer (Odds ratio (OR) 2.27, 95% confidence interval (CI): 1.34-3.85 to OR 3.00, 95%CI: 1.30-6.92) compared to those in the lowest quartile. Futhermore, every 10 beat per minutes (bpm) increase in RHR was associated with 27% (95%CI: 1.03-1.58) increased prevalence of colorectal cancer. In addition, after stratification by age and gender, the result showed that older people (>65 years) in the highest quartile of RHR had a significantly higher prevalence of colorectal cancer compared to those who were in the lowest quartile of RHR. (male OR 3.19, 95%CI: 1.10-9.24 to OR 3.38, 95%CI: 1.18-9.73; female OR 2.90, 95%CI: 1.13-7.42 to OR 5.59, 95%CI: 1.20-25.99). In this study, we examined the feasibility of RHR as a predictive factor of colorectal cancer prevalence. Moreover, we found that RHR was closely related to the prevalence of colorectal cancer in the age of over 65 years.

• Membrane Journal
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• v.2 no.1
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• pp.21-32
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• 1992

Hydrogen-permselective silica membranes were synthesized within tim walls of porous Vycor tubes by chemical vapor depostion of $SiO_2$. Film deposition was carried out using $SiCl_4$ hydrolysis either in the oppm shag reactants or in the one-sided geometry. At temperatures above $600^{\circ}C$ the permeation rate of hydrogen thorough the silica films varied between 0.01 and $025cm^3(STP)/cm^2-min-atm$ depending on the reaction geometry and the $H_2 : N_2$ permeation ratio was about 1000. Permeation rates of both $H_2$ and $N_2$ increased with increasing temperature. The silica membranes produced by one-sided deposition have higher hydrogen permmeation rates than those produced by the opposing reactants geometry although the membranes formed in an opposing reactants geometry were relatively stable during the heat treatment or after exposure to ambient air. These membranes can be applied to high temperature gas separations or membrane reactors once the film deposition process is optimized to get high permeability as well as good stability.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.69-76
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• 2009

This study was conducted to evaluate the physicochemical and sensory characteristics of chiffon cakes made with rice flour ranging from 20-100% in place of wheat flour. The water binding capacity of the rice flour was greater than that of the wheat flour and its fat binding capacity was lower than that of the wheat flour. The batter stability data indicated that the 100% treatment was better than the control, and specific gravity values and specific loaf volumes were lower in the samples with added rice flour. Texture analysis found no significant differences in hardness, adhesiveness, cohesiveness, gumminess, and chewiness between the control and the 100% treatment. In the case of crust color, the rice flour-added chiffon cakes did not show any significant differences for their 'a' values. In addition, their crumb color was not significantly different in terms of both their 'L' and 'a' values. According to the sensory evaluation, there was no significant difference in overall acceptability between the control and the rice flour-added chiffon cakes. The highest sensory scores were obtained by the 100% treatment for overall acceptance and moistness. However, flavor, cohesiveness, and brittleness were not significantly different. These study results show that wheat flour could be replaced by rice flour up to 100% in chiffon cake.

• Elastomers and Composites
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• v.36 no.4
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• pp.246-254
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• 2001

In this work, the stabilization of chlorosulfonated polyethylene (CSM) rubber emulsion with surfactants, i.e., nonionic (Span 60) or anionic (Sodium laurylsulfate, SLS) surfactants, was investigated. The phase inversion emulsification by interfacial chemical characteristics was used to emulsify the CSM rubber. As a result, the emulsion phase separation was observed in the case of any single surfactant. However, there was no phase separation in the mixture of Span 60 and SLS in the context of emulsion droplet size tests and rheological behaviors. The droplet size decreases by increasing the surfactant mixture, resulting in increasing the viscosity. The viscosity and shear stress determined from shear rate show a shear thinning and yield behaviors. It was then found that the emulsion stabilization can be improved using the phase inversion emulsification method and surfactant mixture.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.19-26
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• 2023

The impact of environmental, social and governance (ESG) performance on investors' decision-making is growing. Investors' focus on the financial performance of firms in the past is expanding to the non-financial performance of the interests of stakeholders surrounding firms. Against this backdrop, this study conducted a panel regression analysis on firms evaluated by Korea Corporate Governance Service to analyze the impact of ESG performance, a firm's non-financial performance, on firm risk. According to the analysis, ESG performance has a negative (-) effect on all three firm risks (systematic risk, unsystematic risk, and total risk), indicating that the stakeholder theory and risk management theory are supported. The implications of this study are: First, ESG reduces not only unsystematic risk but also broad and indiscriminate systematic risk; Second, investors can reduce the risk of their investment portfolio by executing ESG investments; Third, companies can achieve stable financial performance even in adverse circumstances by utilizing the insurance function of ESG management; Lastly, the government can enhance the stability of the financial market while improving the financial soundness of firms through reasonable ESG-related regulations.

• Journal of the Korean Geotechnical Society
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• v.29 no.5
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• pp.53-64
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• 2013

Resistivity monitoring is based on the fact that a change in the porosity leads to the changes in water content and fine particles, which alter the electrical resistivity. At every embankment dam, internal erosion always occurs as time passes. The internal erosion generally develops into piping over a long time by backward erosion and concentrated leak, and finally leads to dam failure. Resistivity is known to be very sensitive to the changes in porosity in embankment dams. Thus resistivity monitoring is a reasonable method to find out the leakage zone. However, resistivity is strongly influenced by seasonal variation of temperature, TDS of reservoir water and water level. In this paper. we first installed electrodes permanently at the center of the crest. The electrical resistivity monitoring data was acquired every 6 hours from Apr. 3, 2011 to July. 31, 2012. To analyze the characteristics of monitoring data, each resistivity data was calculated from up to 2,950 data sets. The result indicated a seasonal resistivity variation due to related temperature. Finally, a quantitative method to estimate porosities of the embankment dam from the resistivity monitoring data was analyzed. The applicability and reliability were verified and the importance of electrical resistivity monitoring for obtaining reliable result was emphasized.

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.1-7
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• 2013

Ionic liquids (ILs) have been widely recognized as environmentally benign solvents. Their unique properties, including negligible vapor pressure, non-flammability, a wide liquid range and their tunable physicochemical properties by proper selection of cations and anions, make them attractive green solvents in a variety of fields such as organic synthesis/catalysis, extraction/ separation, and electrochemistry, amongst others. In this paper, the recent technological developments and their prospects in the application of ILs in microbiology and biochemical engineering, including enzymatic reactions, protein folding/refolding and biomass dissolution, are discussed.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.410-415
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• 2001

An analytical and numerical examination of second-order fractional-step methods and boundary condition for the incompressible Navier-Stokes equations is presented. In this study, the compatibility condition for pressure Poisson equation and its boundary conditions, stability, and numerical accuracy of canonical fractional-step methods has been investigated. It has been found that satisfaction of compatibility condition depends on tentative velocity and pressure boundary condition, and that the compatible boundary conditions for type D method and approximately compatible boundary conditions for type P method are proper for divergence-free velocity for type D and approximately divergence-free for type P method. Instability of canonical fractional-step methods is induced by approximation of implicit viscous term with explicit terms, and the stability criteria have been founded with simple model problems and numerical experiments of cavity flow and Taylor vortex flow. The numerical accuracy of canonical fractional-step methods with its consistent boundary conditions shows second-order accuracy except $D_{MM}$ condition, which make approximately first-order accuracy due to weak coupling of boundary conditions.