• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.3
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• pp.223-234
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• 2016

This study aimed to the adsorption-removal of high- radioactive iodide (I) contained in the initially generated high-radioactive seawater waste (HSW), with the use of AgX (Ag-impregnated X zeolite). Adsorption of I by AgX (hereafter denoted as AgX-I adsorption) was increased by increasing the Ag-impregnated concentration in AgX, and its concentration was suitable at about 30 wt%. Because of AgCl precipitation by chloride ions contained in seawater waste, the leaching yields of Ag from AgX (Ag-impregnated concentration : about 30~35 wt%) was less than those in distilled water (< 1 mg/L). AgX-I adsorption was above 99% in the initial iodide concentration ($C_i$) of 0.01~10 mg/L at m/V (ratio of weight of adsorbent to solution volume)=2.5 g/L. This shows that efficient removal of I is possible. AgX-I adsorption was found to be more effective in distilled water than in seawater waste, and the influence of solution temperature was insignificant. Ag-I adsorption was better described by a Freundlich isotherm rather than a Langmuir isotherm. AgX-I adsorption kinetics can be expressed by a pseudo-second order rate equation. The adsorption rate constants ($k_2$) decreased by increasing $C_i$, and conversely increased by increasing the ratio of m/V and the solution temperature. This time, the activation energy of AgX-I adsorption was about 6.3 kJ/mol. This suggests that AgX-I adsorption is dominated by physical adsorption with weaker bonds. The evaluation of thermodynamic parameters (a negative Gibbs free energy and a positive Enthalpy) indicates that AgX-I adsorption is a spontaneous reaction (forward reaction), and an endothermic reaction indicating that higher temperatures are favored.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.6
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• pp.72-88
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• 2014

This study was conducted in order to analyze user behavior and preference factors in the outdoor spaces of mental hospitals. Among hospitals with 250 or more beds, 5 hospitals were selected in consideration of size of garden and diversity of garden elements. The subject of the study was restricted to mild cases of schizophrenia while 30~50 patients were selected on the recommendation of their doctor from 5 hospitals, respectively. The physical environment was analyzed, focusing on space components, after visiting the sites of study. A face to face interview method was selected in consideration of patients' cognitive abilities, a total of 230 questionnaires were used for the analysis. The results of the study can be summarized as follows. Rest facilities occupy the largest numbers in the components of garden, and those are followed by landscape facilities, walking/exercise facilities, and experience facilities. Outdoor walking/exercise programs are classified into group walks and free walks with most patients taking group walks. Most of the patients visit these outdoor spaces every day but some of them rarely use the outdoor areas. In order to increase the efficiency of using these outdoor spaces, the percentage of space for ensuring a sense of control should properly harmonize with the percentage of space to facilitate patients in having social contact. With regard to the reasons for preferring the most widely-used outdoor spaces, landscape/environment property was the most important, followed by functionality and then accessibility. Major activities in the preferred space are mainly composed of walking/exercise and rest. The preferred facilities are waterscape facilities such as ponds, waterfalls and fountains, rest facilities such as pergolas and shade trees, and lawn. It was understood that naturalness should be considered to be the most important factor in constructing a new healing garden, followed by aesthetics and amenities. Single facilities rated by preference for introduction were flower beds, trails, and lawn. According to type, waterscape facilities such as fountains, ponds, waterfalls and waterwheels were most preferred. Space for natural distraction and programs for the cultivation of flower beds were also preferred. The ideal image of a healing garden should be bright, familiar, and orderly as a whole, having plenty of introduced facilities. Open spaces were preferred to enclosed spaces. Finally, the image of a garden that helps patients feel calm was thought to be that of the most ideal garden.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.1
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• pp.41-49
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• 2016

The objective of this study was to determine the effect of different pregnancy stages on the eating and ruminating behavior of Hanwoo heifers (Bos taurus coreanae). A total of twelve Hanwoo heifers were divided into four groups depending on pregnancy stage: C: before pregnancy, 9 months old, T1: 3 months pregnant, 16 months old, T2: 6 months pregnant, 19 months old, T3: 9 months pregnant, 22 months old (3 replicates per group). Concentrate of 1% of the body weight was fed to them. Roughage was provided at ad libitum to all treatments. Our results revealed that the intake of roughage was the highest in the T3 group (at 3.68 kg) and the lowest in the C group (at 1.02 kg, p<0.05). Total intake in the order from high to low was: T3 > T2 > T1 > C (p<0.05). The rate of dry matter intake compared to body weight (DMI/BW, %) from high to low order was: T3 > T2 > T1 > C (p<0.05). Eating time, ruminating time, and chewing time were the highest in T3 group (p<0.05). Resting time was the highest in C group (p<0.05). The number of bolus and the number of total chews were significantly higher in T3 compared to those in other groups. However, ruminating time per bolus was not significantly difference among groups. The number of chews per bolus from high to low order was: C > T1 > T3 > T2 (p<0.05). The number of bolus per minute was not significantly different among groups. The number of drinking and the number of defecating were significantly higher in C and T1, respectively (p<0.05). However, the number of urinating had no effect according to pregnancy stage. Eating rate and chewing efficiency were significantly higher (p<0.05) in accordance with pregnancy stage (T3 > T2 > T1 > C). Ruminating efficiency was significantly (p<0.05) higher T1 than that in other groups.

• Journal of agriculture & life science
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• v.46 no.2
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• pp.9-17
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• 2012

In this study, in addition to the green tea - wood fiber hybrid composite boards of previous researches, to make effective use of saw dust of domestic cypress tree with functionalities and application as interior materials, eco-friendly hybrid composite boards were manufactured from wood fiber, green tea and saw dust of cypress tree. We investigated the effect of the component ratio of saw dust and green tea on dynamic MOE (modulus of elasticity). Dynamic MOE was within 1.41~1.65 GPa, and showed the highest value in wood fiber : green tea : saw dust = 50 : 40 : 10 of the component ratio, and had the lowest value in 50 : 30 : 20 of component ratio. These values were 1.4~1.6 times higher than static bending MOE of wood fiber - saw dust - green tea hybrid composite boards, and were 2.0~2.9 times lower than those of green tea - wood fiber hybrid composite boards reported in the previous researches. From the results of correlation regression analyses between dynamic MOE and static strength performances, a very high correlation coefficients were obtained, therefore it was found that static bending strength performances can be estimated with a high reliability from dynamic MOE.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.4
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• pp.391-400
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• 2015

In the present study, 50% ethanol extract, the ethyl acetate and aglycone fraction were prepared from mate (Ilex paraguariensis) and their antioxidative ability was evaluated. The yields of extract and fractions were 32.0, 4.48 and 0.82% per dried powder, respectively. Free radical scavenging activities were performed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and total antioxidant capacity was estimated using luminol-dependent chemiluminescence assay. Free radical scavenging activities ($FSC_{50}$) of 50 % ethanol extract, ethyl acetate fraction and aglycone fraction were 8.83, 5.84 and $6.05{\mu}g/mL$, respectively. Their total antioxidant capacities ($OSC_{50}$) were similar to that of L-ascorbic acid ($1.72{\mu}g/mL$), known as a prominent water soluble antioxidant, in all extracts and 50% ethanol extract ($1.03{\mu}g/mL$) was the most effective. The cellular protective effects on the $^1O_2$-induced cellular damage of erythrocytes were evaluated and the results showed that all extracts were significantly higher than (+)-${\alpha}$-tocopherol at $10{\mu}g/mL$. Especially, the ${\tau}_{50}$ value of aglycone fraction was 5 times higher than (+)-${\alpha}$-tocopherol at $10{\mu}g/mL$ and $50{\mu}g/mL$. The inhibitory effects of the ethyl acetate and aglycone fractions on tyrosinase were similar to arbutin, known as the whitening agent in cosmetics. These results suggest that the extracts of mate have the applicability as antioxidant and anti-aging cosmeceutical ingredients.

• Journal of Food Hygiene and Safety
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• v.34 no.4
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• pp.388-395
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• 2019

The object of the present study was to examine the effect of selenium-treated Spinacia oleracea L. on antioxidative defense system and oxidative damage in rats fed high-fat and high-cholesterol diets. Experimental rats were divided into six groups which were composed of normal diet group (N), high-fat and high-cholesterol diet group (HF), high-fat and high-cholesterol diet with 5% or 10% non-treated spinach supplemented group (SPA or SPB) and high-fat and high-cholesterol diet with 5% or 10% selenium-treated spinach-supplemented group (SSA or SSB). In the antioxidant enzyme activities of hepatic glutathione peroxidase and superoxide dismutase, activities increased in supplementation of non-treated or selenium-treated spinach groups compared to HF group. However, there was no significant difference in the activity of hepatic catalase among all experimental groups. The microsomal superoxide radical content of the SSB group was significantly reduced compared to the HF group. The mitochondrial carbonyl values of the SSB group were significantly reduced compared to the HF group. Thiobarbituric acid reaction substance (TBARS) values in RBC and liver were also reduced in non-treated or selenium-treated spinach-supplemented groups compared to the HF group. The hepatic TBARS values of the supplementation of selenium-treated spinach groups significantly decreased compared to the supplementation of non-treated spinach groups. These results suggest that selenium-treated spinach may reduce oxidative damage by the activation of antioxidative defense system in rats fed high-fat and high-cholesterol diets.

• Journal of Appropriate Technology
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• v.6 no.1
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• pp.28-36
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• 2020

Sustainable appropriate technology requires user-centered design with consideration of the political, cultural and environmental aspects of the area. However, in the preparation of appropriate technology, there is a limit to the prior grasp of the user's intention and experience leading to the actual behavior of the user after the dissemination. As a result, appropriate technologies are often inconvenient for practical use or used for other purposes, contrary to the designer's intention. This study analyzes the case of appropriate technology with an analysis framework that reflects Maier's affordance theory, and proposes a design solution that can overcome the limitations of existing design. Affordance theory is the theory of factors that cause the user to identify and use features through interpretation based on prior knowledge and experience about things. The analysis cases in this study are the interviews with the designers, management education materials, and manager interviews for water purification systems at three of six schools in Binh Dinh Province, Vietnam, from August 2015 to January 2018. The case was attempted to be improved by periodic installation, maintenance, and inspection, but similar problems continued to occur. First, the facility inspections and manager interviews are compared with manager training materials distributed at the time of installation to find inconsistencies. Next, we analyze the designer's intended affordance and the affordances that actually influenced the management behavior. And then, we propose design solutions based on commonly found problems and affordances. This study suggests that it is necessary to apply the design considering the user's behavior before distributing the appropriate technology, and this study will be precedent in the process of finding the improvement through the analysis framework based on the affordance.

• Journal of Environmental Impact Assessment
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• v.32 no.6
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• pp.389-406
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• 2023

The research area, located in the northern coastal region of South Korea's West Sea, involves three bird habitats. Among these are two newly established habitats in Songdo International Business District, created by filling and developing tidal flats that were previously utilized as stopover sites for migratory birds. One of these areas showed decrease (Residual tidal flats, site.1) while the other showed increase (Artificial lake, site.2) in bird influx. The third habitat (Namdong reservoir, site.3) is a pre-existing stable habitat which has been maintained as a stable habitat. This study conducts an assessment of habitats based on avian population clusters and environmental surveys and proposes habitat management measures. A survey of bird populations and habitat environments was conducted for a total of 39 occasions from January to December 2022. The observed bird species totaled 14 families and 48 species with 20,760 individuals. Compared to the existing habitats, the newly established habitats showed relatively lower influx of bird species and individuals. During the habitat assessment, the newly established habitats were rated as I to II grade, while the existing habitat was rated as relatively high III grade on the grading assessment of the tidal flat. An analysis of habitat types revealed that the existing habitat, in which diverse strategies for habitat type diversity and mitigating anthropogenic interference were demonstrated, attracted a diverse range of bird species. Through this research, it was deduced that the diversity of habitat types plays a significant role in attracting various bird species. Upon evaluation of habitat types concerning the habitat characteristics of the bird species selected for habitat management, as habitat management measures, it is deemed that the creation of shielded green areas (referred to as 'buffer green') to minimize interference from the surroundings, the establishment of reed fields (site.1, 2) positively correlated with reservoirs, and the improvement of sandbanks (site.1) positively associated with tidal flats, the two relations which we drew from correlation analysis between occurrence species and habitat types, would contribute to the future restoration and maintenance of stable habitats. The results of this study can be applied not only to the study area but also to other development zones, such as coastal reclamation sites, which share similar geographical and environmental characteristics, including arrival sites for migratory birds.

• Bulletin of the Society of Naval Architects of Korea
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• v.61 no.1
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• pp.16-29
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• 2024

2014년 4월 18일 오전 8시 48분경 전라남도 병풍도 인근 해역에서 세월호는 전복된 후 침몰하였다. 사고 당시 이 배에는 승객 443명과 선원 및 승무원 33명 모두 476명이 타고 있었고, 이 중 미수습자 5명을 포함하여304명이 생명을 잃었다. 그 동안 공식적인 사고원인 규명활동이 꾸준히 진행되어 이 사고의 원인을 규명하기 위한 조사가 네 차례 있었다. 하지만 아직까지 사고 원인이 무엇인지 명쾌하게 밝혀지지 않고 있다. 이 글에서는 먼저 그동안 있었던 네 차례의 공식적인 세월호 사고원인 규명활동을 정리하였다. 가장 먼저 사고원인 규명활동을 전개한 해양안전심판원 특별조사부는 2014년 사고 직후부터 그해 12월까지 활동하였다. 특별조사부 최종보고서에는 화물의 과적과 평형수 적재 부족으로 인한 선박복원성 기준 미달, 타각의 대각도 조타와 장시간 유지로 인한 부적절한 조타, 화물의 부실한 고박으로 인한 화물의 이동, 수밀문의 관리 부실로 인한 조기 침수와 비상대피장소(muster station)로의 승객대피 조치 미이행을 사고의 원인으로 들고 있다. 2015년 3월부터 2016년 6월까지 활동한 4·16세월호참사 특별조사위원회(특조위)는 '4·16 세월호 참사 특별 조사위원회 청산 백서'만을 간행하고 최종보고서를 제출하지 못한 채 활동을 종료하였다. 세월호 선체조사위원회(선조위)는 2017년 4월부터 2018년 8월까지 활동하였다. 선조위는 세월호 사고원인 규명을 위한 다른 기구에 비해 위원의 구성도 균형이 있었고, 직권사건 위주의 조사방법도 적절하였다. 또한 조타기와 조타 과실 여부, 급선회 항적 및 횡경사와 핀안정기의 물리적 손상에 관한 용역을 국내 여러 기관에 발주하였다. 뿐만 아니라 다양한 해양사고 원인규명 용역에 참여한 실적이 있는 영국의 기술용역회사인 Brookes Bell에 급선회와 빠른 침몰의 원인 조사를 요청하였다. 아울러 세계에서 가장 활발히 수조실험을 수행하고 있는 상업 연구소인 네덜란드의 MARIN에 수조시험과 시뮬레이션도 의뢰하였다. 하지만 아쉽게도 선조위는 서로 다른 사고 원인을 주장하는 두 권의 종합보고서를 간행하였다. 종합보고서로 '내인설' 종합보고서[6]는 타기 솔레노이드 밸브의 고착으로 시작된 급선회를 사고의 직접 원인으로 지목하고 있다. 하지만 '열린안' 종합보고서[7]에서는 수중체와의 충돌을 직접적인 사고 원인으로 밝히고 있다. 마지막으로 가습기살균제 사건과 4·16세월호 참사 특별조사위원회(사참위)가 2019년 3월부터 2022년 9월까지 활동하였다. 사참위는 위원으로 조선해양공학과 항해학 전문가가 포함되어 있지 않아 세월호의 사고원인 규명활동을 효과적으로 수행하기에는 적절하지 못하였다. 사참위는 주로 조타장치 고장에 따른 세월호 전타 선회현상 검증, 세월호 변형 손상부의 확인 및 원인 조사와 세월호 횡경사 원인과 침수과정 분석을 직권 과제로 추진하였다. 또한 네덜란드 MARIN에 자유항주시험을 추가로 의뢰하였으며, 핀란드의 NAPA group에도 복원성 계산과 침수해석을 의뢰하였다. 사참위는 선조위의 두 가지 사고원인에 대해 '내인설'의 솔레노이드 밸브 고착은 사고원인일 가능성이 매우 낮고, '열린안'의 수중체와의 충돌 시나리오는 근거가 부족함을 확인하였다. 이상에서 정리한 바와 같이 규명활동이 진행됨에 따라 사고원인이 수렴되어야 함에도 불구하고 아직까지 원인을 시원하게 밝히지 못하고 있다. 이 글에서는 사고원인 규명활동을 수행한 네 개 기구의 구성과 활동 내용을 비교하고, 사고조사 위원회의 바람직한 구성과 위원회의 운영 방법을 제시하고 있다. 또한 Brookes Bell 보고서에 수록된 출항 당시의 흘수에 근거한 배수량과 선미 램프의 폐쇄 전후의 횡경사각으로부터 도출한 GoM도 소개하고 있다. 아울러 출항 당시의 GoM값으로 추정한 사고 당시의 GoM값도 소개하고 있고, 수중체와의 충돌 시나리오를 후보 사고 시나리오에서 제외시켜야 할 이유도 열거하고 있다. 끝으로 해양사고 원인규명 활동이 보다 과학적으로 그리고 보다 합리적으로 이루어질 수 있기 위해 그리고 우리 사회의 안전문화 제고를 위한 몇 가지의 방안을 제시하고 있다. 또한 세월호 사고로 치른, 아직도 치르고 있는 희생을 딛고 해양안전문화가 한 걸음 더 나아가기 위해서는 세월호 사고의 원인을 반드시 규명해야 한다는 말씀으로 글을 마무리하고 있다.

• The Korean Journal of Air & Space Law and Policy
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• v.35 no.2
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• pp.247-280
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• 2020

For customs-free and liberalization on the trade of aircraft parts, the WTO Agreement on Trade in Civil Aircraft was separately concluded as plurilateral trade agreement at the time of launching WTO in 1995, and currently 33 countries including the United States and the EU are acceded but Korea does not. Major details of the Agreement on Trade in Civil Aircraft include product coverage, the elimination of customs duties and other charges, the prohibition of government-directed procurement of civil aircraft, the application of the Agreement on Subsides and Countervailing Measures, and the consultation on issues related to this Agreement and dispute resolution. Article 89 paragraph 6 of the current Customs Act was newly established on December 31, 2018, and the tariff reduction rate for imports of aircraft parts will be reduced in stages from May 2019 and the tariff reduction system will be abolished in 2026. Accordingly, looking at the impact of the Agreement on Trade in Civil Aircraft on the aviation industry, first, as for the impact on the air transport industry, an tariff allotment of the domestic air transport industry is expected to reach about 160 billion won a year from 2026, and upon acceding to the Agreement on Trade in Civil Aircraft, the domestic air transport industry will be able to import aircraft parts at no tariff, so it will not have to pay 3 to 8 percent import duties. Second, as for the impact on the aviation MRO industry, if the tariff reduction system for aircraft parts is phased out or abolished in stages, overseas outsourcing costs in the engine maintenance and parts maintenance are expected to increase, and upon acceding to the Agreement on Trade in Civil Aircraft, the aviation MRO industry will be able to import aircraft parts at no tariff, so it will reduce overseas outsourcing costs. If the author proposes a policy direction for the trade liberalization of aircraft parts to ensure competitiveness of the aviation industry, first, as for the tariff reduction by the use of FTA, in order to be favored with the tariff reduction by the use of FTA, it is necessary to secure the certificate of origin from foreign traders in the United States and the EU, and to revise the provisions of Korea-Singapore and Korea-EU FTA. Second, as for the push of acceding to the Agreement on Trade in Civil Aircraft, it would be resonable to push the acceding to Agreement on Trade in Civil Aircraft for customs-free on the trade of aircraft parts, as the tariff reduction method by the use of FTA has limits. Third, as for the improvement of the tariff reduction system for aircraft parts under the Customs Act, it is expected that there will take a considerable amount of time until the acceding to the Agreement on Trade in Civil Aircraft, so separate improvement measures are needed to continue the tariff reduction system of aircraft parts under Article 89 paragraph 6 of the Customs Act. In conclusion, Korea should accede to the WTO Agreement on Trade in Civil Aircraft to create an environment in which our aviation industry can compete fairly with foreign aviation industries and ensure competitiveness by achieving customs-free and liberalization on the trade of aircraft parts.