• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.312-318
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• 2016

This study investigated the reduction of residual pesticide in soil by using eight kinds of soil amendments such as shell, quick lime, dolomite, silicic acid, leaf mold, oil cake, bed soil and husk. A total of ten pesticides most frequently detected in agricultural soil were selected (azoxystrobin etc.) and soil amendments were treated in soils at a 2% application rate and incubated for 7 days. Pesticides were analyzed by HPLC-MS/MS with QuEChERS-based sample preparation procedure and pH was measured on 1, 3 and 7 days. This study showed that, soil amemdments were effective in reducing pesticides after 7days of incubation. Over 90% of azoxystrobin, cadusafos, chlorpyrifos, fluquinconazole, imidacloprid, isoprothiolane and procymidone were decomposed from soils amended with 2% quick lime, whereas the concentration of boscalid, dimethomorph and triycyclazole were not decreased. The soil pH increased to 12.8-12.9 in soil amended with quick lime, but other soil conditioners did not change the soil pH. Quick lime was particularly effective in reducing residual pesticides.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.681-688
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• 2018

As environmental regulations have been strengthened and high fuel efficiency has been in demand in recent years, the number of ships using natural gas as a fuel is increasing. The demand for ships using LPG or methanol, which are emerging as eco-friendly vessel fuels, is also increasing. In this perspective, ME-LGI engines using LPG or methanol as a fuel have attracted considerable attention. Ships equipped with an ME-LGI engine are required to check the reliability of the fuel injection valve during shipping. This means that the development of a fuel injection valve tester is essential for the commercialization of ME-LGI engine. This study conducted the conceptual design of a fuel injection valve tester for ME-LGI engines using a system engineering process in the order of requirements analysis, functional analysis, and design synthesis. In the requirement analysis stage, the operating process of fuel injection valve was analyzed, and the necessity of checking the sealing oil leakage was then derived. In the functional analysis stage, the functions and flow of them were defined at each functional level. In the design synthesis stage, the equipment for each function was set and the process block diagram based on it was derived. In addition, preliminary risk analysis was performed as a part of system analysis and control, and safety measures were added to the conceptual design. This study is expected to be a good reference material for the concept design of other systems in the future because it shows the application process of a system engineering process to the conceptual design in detail.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.2
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• pp.41-48
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• 2011

In this study, the soil remediation by landfarming was carried out using microbial activators. Feasibility studies and reduction capacity of TPH(Total Petroleum Hydrocarbons) were investigated in order to find out how fast and eco-friendly the contaminated soil can be recovered. The lab-test confirmed not only the performance and degradation efficiency of microbial activators but also the effect of TPH reduction in the contaminated soil. The optimum growth conditions for indigenous microorganisms were identified using microbial activators. Based on the results of TPH removal, although there had been a little of difference in between natural decomposition and microbial activators until 20 days, the sample groups of microbial activators were higher than the control ones after 20 days. Microbial activators were applied to the field experiments on landfarming. Based on the results of removal rate in each floor of soil, it was found that the removal rates were 85.8 % in the upper, 84.4 % in the middle, and 66.10 % in the bottom. Considering that the reduction rate of TPH for the control group averaged 71.1%, the microbial activators might not be fully transferred into the bottom, which resulted from the piles of soil. As the piles have already reached 1 m in the field experiments, the low piles of soil under 0.6 m may enhance the treatment efficiency of TPH.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.590-596
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• 2019

Uses of fossil fuels like coal and oil increases with industrial development, and problems like abnormal climate come up as greenhouse gas increases. Accordingly, studies are actively conducted on eco-friendly renewable energy as a replacement for the main resources, and especially, wood pellets with high thermal efficiency are in the limelight as an alternative fuel in thermal power stations and gas boilers. However, despite a constant increase in their usage, few studies are conducted on their risks like fire and spontaneous combustion. Thus, this study found the auto-ignition temperature and critical ignition temperature of wood pellets with a change in flow rate in a thermostatic bath, using a sample vessel with 20 cm in length, 20 cm in height and 14 cm in thickness to predict their ignition characteristics. Consequently, at the flow rate of 0 NL/min, as the core temperature of the sample increased to higher than the ambient temperature, they ignited at $153^{\circ}C$, when the critical ignition temperature was $152.5^{\circ}C$. At the flow rates of 0.5 NL/min and 1.0 NL/min, it was $149.5^{\circ}C$, and at the flow rate of 1.5 NL/min, it was $147.5^{\circ}C$. Consequently, at the same storage, the more the flow rate, the lower the critical ignition temperature became.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.4
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• pp.151-163
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• 2022

This study was conducted to promote organic fertilizer(s) that sustain soil productivity for corn production and protect the environment as required by the Act on the promotion of eco-friendly agriculture. It was conducted at the research station of the Organic Agriculture Division of the National Institute of Agricultural. The treatments consisted of Compost (Com), Bokashi as fermented organic fertilizer (FOF), and mixed expeller pressed cake (PC). They were applied at 174 kg N /ha to field corn, together with a 'no fertilizer' check in Randomized Complete Block Design. At eight weeks after transplanting (WAT) corn, compost increased soil carbon (C) and nitrogen (N) to 7.48 and 0.76 g/kg respectively, while other fertilizers maintained the initial levels (before treatment application). At corn harvest (13 WAT), soil chemical properties (total C, total N, pH, electrical conductivity, P₂O₅, Ca, K, and Mg) were similar among all organic fertilizer treatments. For soil respiration, FOF increased soil CO₂ respiration by 31-76% above other fertilizer treatments. However, there were no prominent changes in the trends of CH₄ fluxes following the two mechanical weeding operations. Fermented organic fertilizer affected N₂O emissions between 87-96% lower than other fertilizer treatments. Compared to the initial microbial densities, FOF increased fungi and actinomycete colony foming unit by 25 and 16% at harvest. Therefore, the additional potential of improving soil biological fertility and local availability of raw materials make FOF a better option to sustain soil productivity while protecting the environment.

• Korean Journal of Heritage: History & Science
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• v.54 no.1
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• pp.18-31
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• 2021

Linoleum is a resilient, hygienic, and eco-friendly floor covering. It was developed in England by Frederick Walton in 1863. Made of cork flour, linseed oil, and burlap as its main materials, the flexible and waterproof linoleum became globally popular in the early 20th century. Unlike the vinyl coverings, the burlap-backed linoleum was used not only in commercial spaces but also in household areas like kitchens, bathrooms, and even living rooms. As a global product, linoleum was imported and used in Korean palaces like Deoksugung and Changdeokgung in the early modern period. According to the record Deoksugung Won-Ahn, linoleum was applied to the major buildings, including Hamnyeongjeon, Deokhongjeon, and Jeonggwanheon, and various other venues. The linoleum used in these places are mainly monochrome blue and brown color, which probably means that they are from England. The trade records in the early 20th century show that linoleum was imported mainly from England and America. The Ewangjik building floor plan in the Changdeokgung Palace shows that linoleum was used extensively. There are even some originals, which were laid in 1920 and left in the Changdeokgung Palace. When Daejojeon and Huijeongdang were rebuilt in 1920, the interior was outfitted with western features and linoleum was used in areas such as bathrooms, the tonsorial parlor, and one of the rooms on the west side of Huijeongdang. In situ in the Daejojeon and Huijeongdang areas in the Changdeokgung Palace are monochrome, patterned black, and stylized floral tile patterned, which are closely similar to American products made by ALC and Armstrong company. This study will help us better understand linoleum's characteristics, its uses and the material itself. It will also form the basis for the restoration of Changdeokgung Palace as well as other modern interiors with linoleum flooring in the future.

• Journal of the Korean Applied Science and Technology
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• v.38 no.1
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• pp.19-28
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• 2021

Corrosion is the degradation of metals by reaction with the environment. It is difficult to completely remove. Corrosion proceeds rapidly after the protective barrier is destroyed, and several reactions occur that alter the composition and properties of the metal surface and local environments, such as diffusion of metal cations into the matrix, the formation of oxides, and local pH changes. The study of corrosion of steel and iron is of theoretical and practical interest and is receiving considerable attention. Acid solutions, which are widely used in industrial pickling, acid descaling, cleaning and acidification of oil wells, require the use of corrosion inhibitors to suppress corrosion attacks on metallic materials. Physical removal of rust requires expensive special equipment, and chemical removal of it can cause corrosion or shorten the life of the metal. In this study, an eco-friendly rust cleaner was developed using cosmetics and food materials by applying the concept of perm reducing agent and chelate, and applied to remove rust from industrial and hot water pipes and various industrial devices. As a result, it was found that rust cleaners remove rust more effectively and safely compared to conventional treatment methods. At the same time, the rust removal efficiency was 1.75 to 2.5 times better for industrial piping and 1.56 to 2.2 times better for boiler hot water than conventional methods.

• Journal of Life Science
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• v.33 no.8
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• pp.680-691
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• 2023

Peak oil, climate change, and microplastics caused by the production and usage of petroleum-based plastics have threatened the sustainability of our daily life, and this has emerged as a recent global issue. To solve this global issue, the production and usage of biodegradable eco-friendly bioplastics such as polyhydroxyalkanoates (PHAs) has been suggested as an alternative. Therefore, in this review, the present status of global PHA manufacturers, the advantages of the production of PHAs using marine-origin microorganisms (with their productivity potential) and further required research and development strategies for cost-competitive production of PHAs using marine-based microorganisms were investigated. In this review, PHAs produced from marine microorganisms were found to have similar physical properties to petroleum-based plastics but with several advantages that can reduce the costs of PHA production. Those advantages include, seawater used in the medium preparation step, and osmotic-based cell lysis technology used in the separation and purification steps. However, the PHA productivities from marine microorganisms showed somewhat lower efficiencies than those from the commercial strains isolated from terrestrial environments. In order to solve the problem, further research strategies using synthetic microbiology-based technology, the development of long-term continuous culture technology, and solutions to improve PHA efficiency are required to meet future market demands for alternative bioplastics.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2023.05a
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• pp.110-111
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• 2023

As carbon neutrality has recently emerged as a global issue, the carbon neutral roadmap of MOF has been established and various strategies have been proposed to achieve carbon neutrality in the entire marine industry. The port sector is also included in the target for greenhouse gas reduction, but emissions are not being measured due to limitations in data collection and no inventory construction. For building a carbon-neutral port, it is essential to calculate and forecast emissions and set reduction targets. Accordingly, in this study, CO₂ emitted from domestic port equipment was calculated according to the IPCC Guildeline's emission calculation method, and future emission was estimated. As a result of the analysis, about 420,000 tons of CO₂ was emitted based on the cargo volume in 2020, and emissions are expected to continue to increase in proportion to the increase and about 720,000 tons will be emitted by 2050. In order to achieve carbon neutrality of the port, it needs to promote emission reduction by converting the power source for oil-based equipment to eco-friendly fuel. Also container and miscellaneous ports which require complicated cargo handling need to effort to reduce CO₂.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.11a
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• pp.158-159
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• 2022

Due to the climate crisis, various environmental regulations including greenhouse gas reduction are in effect. This is not limited to any specific industry sector, but is affecting the entire industry worldwide. For this reason, the IMO and governments of each country are announcing strategies and policies related to the shipbuilding and shipping industries. The current regulations can be partially resolved through additional facilities such as scrubbers while using existing fossil fuels, but ultimately, the emission of greenhouse gases such as CO2 from the exhaust gases generated by ships must be restricted through energy conversion. To this end, it is necessary to develop fuels that can replace traditional fuels such as oil and natural gas. Among them, hydrogen is attracting attention as a clean energy that does not emit pollutants when used as a fuel. However, hydrogen has a wide explosive range and a fast dispersion speed, so research on this is necessary. Therefore, in this paper, when hydrogen leakage occurs in the fuel preparation room of a hydrogen-powered ship, the trend was analyzed and the ventilation characteristics were investigated.