• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.731-743
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• 2018

This study was conducted to evaluate the effects of green manures and complemental fertilization with oil cake or liquid fertilizer on growth and nitrogen use efficiency of Chinese cabbage cultivated in organi systems. Field experiments were carried out at the National Institute of Agricultural Science in Suwon, South Korea from 2012 to 2014. Two green manure crops, Crotalaria and Hairy vetch, was cultivated in summer and in winter, respectively. The application methods of the green manure consisted of three tillage systems (overall tillage, partial tillage and no tillage). Oil cake and liquid fertilizer were used as complemental fertilizer. The results showed that when used as covering material in the upland soil without tillage, green manure fertilization was more effective in increasing growth and yield of Chinese cabbage than when incorporated into soil. It was possible to grow and harvest Chinese cabbage in the spring season by the application of hairy vetch as winter green manure. The higher yield of Chinese cabbage with green manure application was caused by the lower incidence rate of soft rot and tip-burn. The yield of the Chines cabbage that received green manure applications over two consecutive seasons followed by the supplemental fertilization with oil cake was similar to that of the conventional chemical fertilization. Following a single season green manure application in summer, however, the yield of cabbage was only about 70% of the conventional treatment. Green manure cultivation with additional liquid fertilization produced a yield similar to the conventional fertilization treatment, soil inorganic nitrogen concentration remained stable and the nitrogen use efficiency increased in the green manure applied soil. In conclusion, the organic cultivation of Chinese cabbage in the autumn season could be outperformed in the upland soil receiving two seasons (winter and summer) of green manure fertilization followed by the supplemental fertilization with liquid fertilizer.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.1177-1192
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• 2018

The objective of this study is to develop the existing drainage system for catching the partial leakage of tunnel structures operating in cold region. The drainage system consists of drainage board, Hotty-gel as a waterproofing material, cover for preventing protrusion of Hotty-gel, air nailer, fixed nail, pipe for collecting ground leak, pipe for conveying ground leak, wire-mesh, and sprayed cement mortar. The drainage systems were installed in conventional concrete lining tunnels to evaluate the site applicability and constructability. The performances of waterproof and the drainage in the drainage system were evaluated by injecting 1,000 ml of red water in the back of the drainage system at 7 days, 14 days, 21 days, 28 days, 2 months, 3 months, 4 months, 5 months, 6 months, 7 months and 8 months. During 8 months of field test, the average daily temperature of the tunnel site was measured from $-16.0^{\circ}C$ to $25.6^{\circ}C$. The daily minimum temperature was $-21.3^{\circ}C$ and the daily maximum temperature was $30.8^{\circ}C$. There was no problem in waterproof and drainage performance of the drainage board in the drainage system. However, the pipe for conveying ground leak had the leakage problem from 14 days. It is considered that the leakage of the pipe for conveying ground leak was caused by the deformation of the pipe of the flexible plastic material having a thickness of 0.2 cm by using the high pressure air nailer and the fixing pin and the insufficient thickness and width of the hotty-gel for preventing the leakage.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.6
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• pp.991-999
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• 2018

In urban areas, the proportion of railway traffic in public transport is increasing. The congestion situation is repeated as the passengers concentrate on station and transfer facilities and the inconvenience of the passengers is increasing in terms of safety and convenience. Therefore, the importance of estimating the appropriate area of the station has been emphasized. The area estimation formula used in the metropolitan railway stations currently is a partial modification of the area estimation formula of Japan in the 1970s. It does not reflect changes in the social and cultural environment and patterns of passengers. The technical basis for major decision variables is insufficient. Therefore, the theoretical basis of the area estimation formula and the pedestrian environment satisfaction of the design guideline of metropolitan railway stations were analyzed in order to suggest improvement formula. The improved area estimation formula was verified by conducting field surveys on 5 stations of metropolitan railways and 15 stations of urban railways. The existing area estimation formula is LOS E grade for the main space. However, the LOS D grade is implemented when the improved area estimation formula is applied. Based on the results, the design factors for the area estimation formula are suggested.

• Journal of Electrochemical Science and Technology
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• v.9 no.4
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• pp.282-291
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• 2018

The pristine fluorine-doped $SnO_2$ (abbreviated as FTO) inverse opal (IO) was developed using a 410 nm polystyrene bead template. The nanolayered copper tungsten oxide ($CuWO_4$) was decorated on the FTO IO film using a facile electrochemical deposition, subsequently followed by annealing at $500^{\circ}C$ for 90 min. The morphologies, crystalline structure, optical properties and photoelectrochemical characteristics of the FTO and $CuWO_4$-decorated FTO (briefly denoted as $FTO/CuWO_4$) IO film were investigated by field emission scanning electron microscopy, X-ray diffraction, UV-vis spectroscopy and electrochemical impedance spectroscopy, showing FTO IO in the hexagonally closed-pack arrangement with a pore diameter and wall thickness of about 300 nm and 20 nm, respectively. Above this film, the $CuWO_4$ was electrodeposited by controlling the cycling number in cyclic voltammetry, suggesting that the $CuWO_4$ formed during 4 cycles (abbreviated as $CuWO_4$(4 cycles)) on FTO IO film exhibited partial distribution of $CuWO_4$ nanoparticles. Additional distribution of $CuWO_4$ nanoparticles was observed in the case of $FTO/CuWO_4$(8 cycles) IO film. The $CuWO_4$ layer exhibits triclinic structure with an indirect band gap of approximately 2.5 eV and shows the enhanced visible light absorption. The photoelectrochemical (PEC) behavior was evaluated in the 0.5 M $Na_2SO_4$ solution under solar illumination, suggesting that the $FTO/CuWO_4$(4 cycles) IO films exhibit a photocurrent density ($J_{sc}$) of $0.42mA/cm^2$ at 1.23 V vs. reversible hydrogen electrode (RHE, denoted as $V_{RHE}$), while the FTO IO and $FTO/CuWO_4$(8 cycles) IO films exhibited a $J_{sc}$ of 0.14 and $0.24mA/cm^2$ at $1.23V_{RHE}$, respectively. This difference can be explained by the increased visible light absorption by the $CuWO_4$ layer and the favorable charge separation/transfer event in the cascading band alignment between FTO and $CuWO_4$ layer, enhancing the overall PEC performance.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.6
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• pp.120-126
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• 2018

The study conducted an experiment in which residual aggregate and polypropylene fibers are mixed in concrete, and an experiment in which granite and polypropylene fibers are mixed. Two types of experiments, in particular, changed the amount of polypropylene fibers, and examined the mechanical properties of slump, compressive strength, tensile strength and the like. To establish a light and easy-to-use material for landscape construction and packaging material development by comparing two kinds of experimental results, comparing and analyzing residual aggregate as experimental materials and materials using granite soil to prevent partial destruction due to cracks in drying shrinkage. The more the amount of the PP fibers increases in concrete, the more the volume of the PP fibers increases, the less the slump is determined. As a result of the compressive strength, the cast-down earth concrete is measured to be about 59% to 71% of the concrete strength. As the amount of PP fibers mixed in increased, the compression strength showed a relative decrease. As a result of tensile strength, it is found that the granite concrete is about 68-67% of concrete tensile strength. It was found that the compression strength decreased as the amount of PP fibers mixed in concrete or fire-gant concrete was increased. Then, when polypropylene fibers are mixed in the concrete and the concrete, it is found that tensile strength is increased. By analyzing these results, a fixed amount of PP fiber is mixed in the concrete mixed with the granite soil and utilized for various structures in the field of landscape construction or materials related to packaging, the prevention and improvement effect of the structure is determined.

• Journal of Korea Trade
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• v.25 no.5
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• pp.39-57
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• 2021

Purpose - This research uses ocean marine insurance (OMI) statistics, international emails, focus-group interviews, and surveys to fill the gap between the theory of behavioral insurance, particularly status quo bias (SQB), and the practice of OMI in Korea. The contractual forms of OMI, the oldest and most globalized form of commercial insurance, were developed in the UK as the Institute Cargo Clauses in 1906 and revised in 1963, 1982, and 2009. SQB has been academically explored, mostly in health insurance and the financial services sector, but never in OMI. Thanks to the availability of OMI statistics in Korea, we can conduct SQB research here for the first time in this field. Design/methodology - We show the existence of SQB in the OMI of Korea through Korean statistics between 2009 and 2018, email correspondence with experts in the UK, Germany, and Japan, focus-group interviews with Korean OMI underwriters, an in-depth interview with one underwriter, and a survey of 15 OMI insureds (company representatives). Findings - We find that Korean foreign traders rely on the old-type OMI contracts developed in 1963, whereas other industrialized countries use the newest type of OMI contract developed in 2009. With a simple loss ratio analysis during 2009-2018, we show that the behavior of insurers has little to do with rational profit maximization and is instead driven by irrational bias, as they forgo the more profitable contracts provided by the new clauses by keeping the old clauses. The consistent addiction to old types of contracts in the OMI market suggests strong SQB among Korean exporters, importers, bankers, or insurers, which we confirmed in our interviews and survey. Originality/value - This research has significant originality and academic value because it reports new findings with crucial implications for the development of efficient trade practices and policy. First, this research is based on actual statistics that have not been used in previous Korean research on OMI. Second, this research shows that all-risk OMI policies provide more value to insureds, in terms of coverage given premium, than partial coverage policies, which differs from arguments previously made in Korea. Third, this research reveals strong SQB in Korea, where foreign trade plays a pivotal role in economic growth. That bias could be attributable to uninformed traders, informed but idle insurers, or conservative bankers. Fourth, to further develop foreign trade, policy initiatives are needed to review the current practices of OMI contracts and move forward with the new contract forms. All of these findings and arguments are both new and important.

• The Journal of the Convergence on Culture Technology
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• v.7 no.3
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• pp.599-604
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• 2021

In an era where AI artificial intelligence converges into each field, design of AI-CARE function and UI UX design are in the spotlight. The application of shape design and the trend of color are important for visual effects to match new features. In this paper, we would like to use this to present an example of the arrangement and application of form trends and to present design directions. In the introduction, the latest design environmental factors were analyzed and studied in the direction of the new proposal. In the text, the design direction and consideration of the design in the planning were studied by separating the functional design form, and the direction of the design work was presented. At the stage of form and color, a plan was proposed to match the flow of minimalism, universal design, and affordance design. A study method based on case practice is a consideration of how to consider content on shapes and colors specialized in the partial design work, and proposed to enable graphic production of new areas of UI UX in content images to be feasible. Through this study, the design direction and planning of the derivative method of shape and color was reached by suggesting design directionality and validity for each AI CARE bed PART.

• Journal of Korean Library and Information Science Society
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• v.52 no.2
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• pp.235-252
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• 2021

As part of effort to develop the strategies of internationalization of social science academic journals in South Korea, this study attempts to verify the measurement invariance of journal selection criteria across the groups of library and information science researchers and social science researchers. The authors collected 146 survey responses from researchers who have published at least one paper in SSCI/Scopus-indexed social science journals between 2014 and 2016. As a result of the study, it was found that the configural and partial metric invariance of the journal selection criteria held across the two groups, implying that the model of journal selection criteria is appropriate to use in the field of social science as well as library and information science. Additionally, the authors investigated the perceptions of journal selection criteria indicators in the two groups, and it was shown that researchers in both groups considered peer review and indexing in major databases important. The findings of this study could be useful for publishers or academic societies to develop improvement strategies of their journals.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.340-348
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• 2021

Continuous monitoring of RGB (Red, Green, Blue) vegetation indices is important to apply remote sensing technology for the estimation of crop growth. In this study, we evaluated the performance of eight vegetation indices derived from soybean RGB images with various agronomic parameters under drought stress condition. Drought stress influenced the behavior of various RGB vegetation indices related soybean canopy architecture and leaf color. In particular, reported vegetation indices such as ExGR (Excessive green index minus excess red index), Ipca (Principal Component Analysis Index), NGRDI (Normalized Green Red Difference Index), VARI (Visible Atmospherically Resistance Index), SAVI (Soil Adjusted Vegetation Index) were effective tools in obtaining canopy coverage and leaf chlorophyll content in soybean field. In addition, the RGB vegetation indices related to leaf color responded more sensitively to drought stress than those related to canopy coverage. The PLS-DA (Partial Squares-Discriminant Analysis) results showed that the separation of RGB vegetation indices was distinct by drought stress. The results, yet preliminary, display the potential of applying vegetation indices based on RGB images as a tool for monitoring crop environmental stress.

• Journal of Industrial Convergence
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• v.20 no.3
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• pp.99-109
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• 2022

The purpose of this paper is to verify the mediating effect of peer relations and self-esteem in the relationship between the effects of deficiency of children using local children's centers on school life adaptation. The survey subjects were selected from 424 students in the first year of middle school who were used the local children's center, and analyzed using data from the 4th of the local children's center. Summarizing the analysis results, peer relationships were found to have a complete mediating effect in the relationship between deficiency and school life adaptation. Second, it was verified that self-esteem has a partial mediating effect in the relationship between deficiency and school life adaptation. Children using local children's centers experience deficiencies in various areas of society, but as can be seen from the results of this study, it was suggested that they can help adapt to school life by promoting self-esteem and peer relationships. Therefore, we would like to propose the development of programs and practical implications for promoting children's adaptation to school life, and the expansion of the field of children's research using local children's centers.